Initial commit

149 files changed, 5235 insertions, 0 deletions

diff --git a/src/clients/deps-exe/s6-dnsip4 b/src/clients/deps-exe/s6-dnsip4
new file mode 100644
index 0000000..4181fd6
--- /dev/null
+++ b/src/clients/deps-exe/s6-dnsip4
@@ -0,0 +1,4 @@
+-ls6dns
+-lskarnet
+${SOCKET_LIB}
+${TAINNOW_LIB}
diff --git a/src/clients/deps-exe/s6-dnsip4-filter b/src/clients/deps-exe/s6-dnsip4-filter
new file mode 100644
index 0000000..2c61392
--- /dev/null
+++ b/src/clients/deps-exe/s6-dnsip4-filter
@@ -0,0 +1,6 @@
+libs6dnsgenericfilter.a
+-lskadns
+-ls6dns
+-lskarnet
+${SOCKET_LIB}
+${TAINNOW_LIB}
diff --git a/src/clients/deps-exe/s6-dnsip6 b/src/clients/deps-exe/s6-dnsip6
new file mode 100644
index 0000000..4181fd6
--- /dev/null
+++ b/src/clients/deps-exe/s6-dnsip6
@@ -0,0 +1,4 @@
+-ls6dns
+-lskarnet
+${SOCKET_LIB}
+${TAINNOW_LIB}
diff --git a/src/clients/deps-exe/s6-dnsip6-filter b/src/clients/deps-exe/s6-dnsip6-filter
new file mode 100644
index 0000000..2c61392
--- /dev/null
+++ b/src/clients/deps-exe/s6-dnsip6-filter
@@ -0,0 +1,6 @@
+libs6dnsgenericfilter.a
+-lskadns
+-ls6dns
+-lskarnet
+${SOCKET_LIB}
+${TAINNOW_LIB}
diff --git a/src/clients/deps-exe/s6-dnsmx b/src/clients/deps-exe/s6-dnsmx
new file mode 100644
index 0000000..4181fd6
--- /dev/null
+++ b/src/clients/deps-exe/s6-dnsmx
@@ -0,0 +1,4 @@
+-ls6dns
+-lskarnet
+${SOCKET_LIB}
+${TAINNOW_LIB}
diff --git a/src/clients/deps-exe/s6-dnsname b/src/clients/deps-exe/s6-dnsname
new file mode 100644
index 0000000..4181fd6
--- /dev/null
+++ b/src/clients/deps-exe/s6-dnsname
@@ -0,0 +1,4 @@
+-ls6dns
+-lskarnet
+${SOCKET_LIB}
+${TAINNOW_LIB}
diff --git a/src/clients/deps-exe/s6-dnsname-filter b/src/clients/deps-exe/s6-dnsname-filter
new file mode 100644
index 0000000..2c61392
--- /dev/null
+++ b/src/clients/deps-exe/s6-dnsname-filter
@@ -0,0 +1,6 @@
+libs6dnsgenericfilter.a
+-lskadns
+-ls6dns
+-lskarnet
+${SOCKET_LIB}
+${TAINNOW_LIB}
diff --git a/src/clients/deps-exe/s6-dnsns b/src/clients/deps-exe/s6-dnsns
new file mode 100644
index 0000000..4181fd6
--- /dev/null
+++ b/src/clients/deps-exe/s6-dnsns
@@ -0,0 +1,4 @@
+-ls6dns
+-lskarnet
+${SOCKET_LIB}
+${TAINNOW_LIB}
diff --git a/src/clients/deps-exe/s6-dnsq b/src/clients/deps-exe/s6-dnsq
new file mode 100644
index 0000000..4181fd6
--- /dev/null
+++ b/src/clients/deps-exe/s6-dnsq
@@ -0,0 +1,4 @@
+-ls6dns
+-lskarnet
+${SOCKET_LIB}
+${TAINNOW_LIB}
diff --git a/src/clients/deps-exe/s6-dnsqr b/src/clients/deps-exe/s6-dnsqr
new file mode 100644
index 0000000..4181fd6
--- /dev/null
+++ b/src/clients/deps-exe/s6-dnsqr
@@ -0,0 +1,4 @@
+-ls6dns
+-lskarnet
+${SOCKET_LIB}
+${TAINNOW_LIB}
diff --git a/src/clients/deps-exe/s6-dnsqualify b/src/clients/deps-exe/s6-dnsqualify
new file mode 100644
index 0000000..295d71e
--- /dev/null
+++ b/src/clients/deps-exe/s6-dnsqualify
@@ -0,0 +1,2 @@
+-ls6dns
+-lskarnet
diff --git a/src/clients/deps-exe/s6-dnssoa b/src/clients/deps-exe/s6-dnssoa
new file mode 100644
index 0000000..4181fd6
--- /dev/null
+++ b/src/clients/deps-exe/s6-dnssoa
@@ -0,0 +1,4 @@
+-ls6dns
+-lskarnet
+${SOCKET_LIB}
+${TAINNOW_LIB}
diff --git a/src/clients/deps-exe/s6-dnssrv b/src/clients/deps-exe/s6-dnssrv
new file mode 100644
index 0000000..4181fd6
--- /dev/null
+++ b/src/clients/deps-exe/s6-dnssrv
@@ -0,0 +1,4 @@
+-ls6dns
+-lskarnet
+${SOCKET_LIB}
+${TAINNOW_LIB}
diff --git a/src/clients/deps-exe/s6-dnstxt b/src/clients/deps-exe/s6-dnstxt
new file mode 100644
index 0000000..4181fd6
--- /dev/null
+++ b/src/clients/deps-exe/s6-dnstxt
@@ -0,0 +1,4 @@
+-ls6dns
+-lskarnet
+${SOCKET_LIB}
+${TAINNOW_LIB}
diff --git a/src/clients/deps-exe/s6-randomip b/src/clients/deps-exe/s6-randomip
new file mode 100644
index 0000000..e027835
--- /dev/null
+++ b/src/clients/deps-exe/s6-randomip
@@ -0,0 +1,3 @@
+-lskarnet
+${SOCKET_LIB}
+${TAINNOW_LIB}
diff --git a/src/clients/deps-lib/s6dnsgenericfilter b/src/clients/deps-lib/s6dnsgenericfilter
new file mode 100644
index 0000000..2d5eee8
--- /dev/null
+++ b/src/clients/deps-lib/s6dnsgenericfilter
@@ -0,0 +1,2 @@
+s6dns_generic_filter_main.o
+s6dns_namescanner.o
diff --git a/src/clients/s6-dnsip4-filter.c b/src/clients/s6-dnsip4-filter.c
new file mode 100644
index 0000000..6d6862e
--- /dev/null
+++ b/src/clients/s6-dnsip4-filter.c
@@ -0,0 +1,52 @@
+/* ISC license. */
+
+#include <skalibs/bytestr.h>
+#include <skalibs/fmtscan.h>
+#include <skalibs/strerr2.h>
+#include <skalibs/stralloc.h>
+#include <s6-dns/s6dns-constants.h>
+#include <s6-dns/s6dns-message.h>
+#include "s6dns-generic-filter.h"
+
+#define USAGE "s6-dnsip4-filter [ -l lines ] [ -c concurrency ] [ -t timeout ] [ -f format ] [ -e errorformat ]"
+
+typedef struct s6dns_a1_s s6dns_a1_t, *s6dns_a1_t_ref ;
+struct s6dns_a1_s
+{
+  char ip[4] ;
+  unsigned int got : 1 ;
+} ;
+
+static int s6dns_message_parse_answer_a1 (s6dns_message_rr_t const *rr, char const *packet, unsigned int packetlen, unsigned int pos, unsigned int section, void *stuff)
+{
+  if ((section == 2) && (rr->rtype == S6DNS_T_A) && (rr->rdlength == 4))
+  {
+    s6dns_a1_t *data = stuff ;
+    if (data->got) return 1 ;
+    byte_copy(data->ip, 4, packet+pos) ;
+    data->got = 1 ;
+  }
+  (void)packetlen ;
+  return 1 ;
+}
+
+static int ipformatter (stralloc *sa, char const *packet, unsigned int packetlen)
+{
+  s6dns_a1_t data ;
+  s6dns_message_header_t h ;
+  register int r ;
+  data.got = 0 ;
+  r = s6dns_message_parse(&h, packet, packetlen, &s6dns_message_parse_answer_a1, &data) ;
+  if (r <= 0) return r ;
+  if (!data.got) return 1 ;
+  if (!stralloc_readyplus(sa, IP4_FMT)) return -1 ;
+  sa->len += ip4_fmt(sa->s + sa->len, data.ip) ;
+  stralloc_0(sa) ;
+  return 1 ;
+}
+
+int main (int argc, char const *const *argv, char const *const *envp)
+{
+  PROG = "s6-dnsip4-filter" ;
+  return s6dns_generic_filter_main(argc, argv, envp, S6DNS_T_A, &s6dns_namescanner, &ipformatter, USAGE) ;
+}
diff --git a/src/clients/s6-dnsip4.c b/src/clients/s6-dnsip4.c
new file mode 100644
index 0000000..03c52dd
--- /dev/null
+++ b/src/clients/s6-dnsip4.c
@@ -0,0 +1,62 @@
+/* ISC license. */
+
+#include <errno.h>
+#include <skalibs/uint.h>
+#include <skalibs/sgetopt.h>
+#include <skalibs/bytestr.h>
+#include <skalibs/strerr2.h>
+#include <skalibs/buffer.h>
+#include <skalibs/tai.h>
+#include <skalibs/random.h>
+#include <s6-dns/s6dns.h>
+
+#define USAGE "s6-dnsip4 [ -q ] [ -r ] [ -t timeout ] domain"
+#define dieusage() strerr_dieusage(100, USAGE)
+
+int main (int argc, char const *const *argv)
+{
+  stralloc ips = STRALLOC_ZERO ;
+  tain_t deadline ;
+  unsigned int i = 0 ;
+  int flagqualify = 0 ;
+  int flagunsort = 0 ;
+  PROG = "s6-dnsip4" ;
+
+  for (;;)
+  {
+    register int opt = subgetopt(argc, argv, "qrt:") ;
+    if (opt == -1) break ;
+    switch (opt)
+    {
+      case 'q' : flagqualify = 1 ; break ;
+      case 'r' : flagunsort = 1 ; break ;
+      case 't' : if (!uint0_scan(subgetopt_here.arg, &i)) dieusage() ; break ;
+      default : dieusage() ;
+    }
+  }
+  argc -= subgetopt_here.ind ; argv += subgetopt_here.ind ;
+  if (argc < 1) dieusage() ;
+
+  tain_now_g() ;
+  if (i) tain_from_millisecs(&deadline, i) ; else deadline = tain_infinite_relative ;
+  tain_add_g(&deadline, &deadline) ;
+  if (!s6dns_init()) strerr_diefu1sys(111, "s6dns_init") ;
+  {
+    register int r = s6dns_resolve_a_g(&ips, argv[0], str_len(argv[0]), flagqualify, &deadline) ;
+    if (r < 0) strerr_diefu2sys((errno == ETIMEDOUT) ? 99 : 111, "resolve ", argv[0]) ;
+    if (!r) strerr_diefu4x(2, "resolve ", argv[0], ": ", s6dns_constants_error_str(errno)) ;
+  }
+  if (!ips.len) return 1 ;
+  if (flagunsort) random_unsort(ips.s, ips.len / 4, 4) ;
+  for (i = 0 ; i < ips.len / 4 ; i++)
+  {
+    char fmt[IP4_FMT] ;
+    register unsigned int n = ip4_fmt(fmt, ips.s + 4 * i) ;
+    fmt[n++] = '\n' ;
+    if (buffer_put(buffer_1small, fmt, n) < (int)n)
+      strerr_diefu1sys(111, "write to stdout") ;
+  }
+  if (!buffer_flush(buffer_1small))
+    strerr_diefu1sys(111, "write to stdout") ;
+  return 0 ;
+}
diff --git a/src/clients/s6-dnsip6-filter.c b/src/clients/s6-dnsip6-filter.c
new file mode 100644
index 0000000..a5c7418
--- /dev/null
+++ b/src/clients/s6-dnsip6-filter.c
@@ -0,0 +1,52 @@
+/* ISC license. */
+
+#include <skalibs/bytestr.h>
+#include <skalibs/fmtscan.h>
+#include <skalibs/strerr2.h>
+#include <skalibs/stralloc.h>
+#include <s6-dns/s6dns-constants.h>
+#include <s6-dns/s6dns-message.h>
+#include "s6dns-generic-filter.h"
+
+#define USAGE "s6-dnsip6-filter [ -l lines ] [ -c concurrency ] [ -t timeout ] [ -f format ] [ -e errorformat ]"
+
+typedef struct s6dns_aaaa1_s s6dns_aaaa1_t, *s6dns_aaaa1_t_ref ;
+struct s6dns_aaaa1_s
+{
+  char ip[16] ;
+  unsigned int got : 1 ;
+} ;
+
+static int s6dns_message_parse_answer_aaaa1 (s6dns_message_rr_t const *rr, char const *packet, unsigned int packetlen, unsigned int pos, unsigned int section, void *stuff)
+{
+  if ((section == 2) && (rr->rtype == S6DNS_T_AAAA) && (rr->rdlength == 16))
+  {
+    s6dns_aaaa1_t *data = stuff ;
+    if (data->got) return 1 ;
+    byte_copy(data->ip, 16, packet+pos) ;
+    data->got = 1 ;
+  }
+  (void)packetlen ;
+  return 1 ;
+}
+
+static int ipformatter (stralloc *sa, char const *packet, unsigned int packetlen)
+{
+  s6dns_aaaa1_t data ;
+  s6dns_message_header_t h ;
+  register int r ;
+  data.got = 0 ;
+  r = s6dns_message_parse(&h, packet, packetlen, &s6dns_message_parse_answer_aaaa1, &data) ;
+  if (r <= 0) return r ;
+  if (!data.got) return 1 ;
+  if (!stralloc_readyplus(sa, IP6_FMT)) return -1 ;
+  sa->len += ip6_fmt(sa->s + sa->len, data.ip) ;
+  stralloc_0(sa) ;
+  return 1 ;
+}
+
+int main (int argc, char const *const *argv, char const *const *envp)
+{
+  PROG = "s6-dnsip6-filter" ;
+  return s6dns_generic_filter_main(argc, argv, envp, S6DNS_T_AAAA, &s6dns_namescanner, &ipformatter, USAGE) ;
+}
diff --git a/src/clients/s6-dnsip6.c b/src/clients/s6-dnsip6.c
new file mode 100644
index 0000000..e07ba53
--- /dev/null
+++ b/src/clients/s6-dnsip6.c
@@ -0,0 +1,62 @@
+/* ISC license. */
+
+#include <errno.h>
+#include <skalibs/uint.h>
+#include <skalibs/sgetopt.h>
+#include <skalibs/bytestr.h>
+#include <skalibs/strerr2.h>
+#include <skalibs/buffer.h>
+#include <skalibs/tai.h>
+#include <skalibs/random.h>
+#include <s6-dns/s6dns.h>
+
+#define USAGE "s6-dnsip6 [ -q ] [ -r ] [ -t timeout ] domain"
+#define dieusage() strerr_dieusage(100, USAGE)
+
+int main (int argc, char const *const *argv)
+{
+  stralloc ips = STRALLOC_ZERO ;
+  tain_t deadline ;
+  unsigned int i = 0 ;
+  int flagqualify = 0 ;
+  int flagunsort = 0 ;
+  PROG = "s6-dnsip6" ;
+
+  for (;;)
+  {
+    register int opt = subgetopt(argc, argv, "qrt:") ;
+    if (opt == -1) break ;
+    switch (opt)
+    {
+      case 'q' : flagqualify = 1 ; break ;
+      case 'r' : flagunsort = 1 ; break ;
+      case 't' : if (!uint0_scan(subgetopt_here.arg, &i)) dieusage() ; break ;
+      default : dieusage() ;
+    }
+  }
+  argc -= subgetopt_here.ind ; argv += subgetopt_here.ind ;
+  if (argc < 1) dieusage() ;
+
+  tain_now_g() ;
+  if (i) tain_from_millisecs(&deadline, i) ; else deadline = tain_infinite_relative ;
+  tain_add_g(&deadline, &deadline) ;
+  if (!s6dns_init()) strerr_diefu1sys(111, "s6dns_init") ;
+  {
+    register int r = s6dns_resolve_aaaa_g(&ips, argv[0], str_len(argv[0]), flagqualify, &deadline) ;
+    if (r < 0) strerr_diefu2sys((errno == ETIMEDOUT) ? 99 : 111, "resolve ", argv[0]) ;
+    if (!r) strerr_diefu4x(2, "resolve ", argv[0], ": ", s6dns_constants_error_str(errno)) ;
+  }
+  if (!ips.len) return 1 ;
+  if (flagunsort) random_unsort(ips.s, ips.len / 16, 16) ;
+  for (i = 0 ; i < ips.len / 16 ; i++)
+  {
+    char fmt[IP6_FMT] ;
+    register unsigned int n = ip6_fmt(fmt, ips.s + 16 * i) ;
+    fmt[n++] = '\n' ;
+    if (buffer_put(buffer_1small, fmt, n) < (int)n)
+      strerr_diefu1sys(111, "write to stdout") ;
+  }
+  if (!buffer_flush(buffer_1small))
+    strerr_diefu1sys(111, "write to stdout") ;
+  return 0 ;
+}
diff --git a/src/clients/s6-dnsmx.c b/src/clients/s6-dnsmx.c
new file mode 100644
index 0000000..a495cb2
--- /dev/null
+++ b/src/clients/s6-dnsmx.c
@@ -0,0 +1,64 @@
+/* ISC license. */
+
+#include <errno.h>
+#include <skalibs/uint16.h>
+#include <skalibs/uint.h>
+#include <skalibs/bytestr.h>
+#include <skalibs/sgetopt.h>
+#include <skalibs/strerr2.h>
+#include <skalibs/buffer.h>
+#include <skalibs/tai.h>
+#include <skalibs/genalloc.h>
+#include <skalibs/random.h>
+#include <s6-dns/s6dns.h>
+
+#define USAGE "s6-dnsmx [ -q ] [ -r ] [ -t timeout ] name"
+#define dieusage() strerr_dieusage(100, USAGE)
+
+int main (int argc, char const *const *argv)
+{
+  genalloc mxs = GENALLOC_ZERO ; /* array of s6dns_message_rr_mx_t */
+  tain_t deadline ;
+  unsigned int i = 0 ;
+  int flagqualify = 0 ;
+  int flagunsort = 0 ;
+  PROG = "s6-dnsmx" ;
+  for (;;)
+  {
+    register int opt = subgetopt(argc, argv, "qrt:") ;
+    if (opt == -1) break ;
+    switch (opt)
+    {
+      case 'q' : flagqualify = 1 ; break ;
+      case 'r' : flagunsort = 1 ; break ;
+      case 't' : if (!uint0_scan(subgetopt_here.arg, &i)) dieusage() ; break ;
+      default : dieusage() ;
+    }
+  }
+  argc -= subgetopt_here.ind ; argv += subgetopt_here.ind ;
+  if (argc < 1) dieusage() ;
+
+  tain_now_g() ;
+  if (i) tain_from_millisecs(&deadline, i) ; else deadline = tain_infinite_relative ;
+  tain_add_g(&deadline, &deadline) ;
+  if (!s6dns_init()) strerr_diefu1sys(111, "s6dns_init") ;
+  {
+    register int r = s6dns_resolve_mx_g(&mxs, argv[0], str_len(argv[0]), flagqualify, &deadline) ;
+    if (r < 0) strerr_diefu2sys((errno == ETIMEDOUT) ? 99 : 111, "resolve ", argv[0]) ;
+    if (!r) strerr_diefu4x(2, "resolve ", argv[0], ": ", s6dns_constants_error_str(errno)) ;
+  }
+  if (!genalloc_len(s6dns_message_rr_mx_t, &mxs)) return 1 ;
+  if (flagunsort) random_unsort(mxs.s, genalloc_len(s6dns_message_rr_mx_t, &mxs), sizeof(s6dns_message_rr_mx_t)) ;
+  for (i = 0 ; i < genalloc_len(s6dns_message_rr_mx_t, &mxs) ; i++)
+  {
+    char buf[S6DNS_FMT_MX] ;
+    register unsigned int len = s6dns_fmt_mx(buf, S6DNS_FMT_MX, genalloc_s(s6dns_message_rr_mx_t, &mxs) + i) ;
+    if (!len) strerr_diefu1sys(111, "format result") ;
+    if (buffer_put(buffer_1, buf, len) < 0) goto err ;
+    if (buffer_put(buffer_1, "\n", 1) < 0) goto err ;
+  }
+  if (!buffer_flush(buffer_1)) goto err ;
+  return 0 ;
+ err:
+  strerr_diefu1sys(111, "write to stdout") ;
+}
diff --git a/src/clients/s6-dnsname-filter.c b/src/clients/s6-dnsname-filter.c
new file mode 100644
index 0000000..6522003
--- /dev/null
+++ b/src/clients/s6-dnsname-filter.c
@@ -0,0 +1,83 @@
+/* ISC license. */
+
+#include <errno.h>
+#include <skalibs/error.h>
+#include <skalibs/strerr2.h>
+#include <skalibs/fmtscan.h>
+#include <skalibs/stralloc.h>
+#include <s6-dns/s6dns-constants.h>
+#include <s6-dns/s6dns-domain.h>
+#include <s6-dns/s6dns-message.h>
+#include "s6dns-generic-filter.h"
+
+#define USAGE "s6-dnsname-filter [ -4 ] [ -6 ] [ -l lines ] [ -c concurrency ] [ -t timeout ] [ -f format ] [ -e errorformat ]"
+
+static unsigned int ipscanner (s6dns_domain_t_ref d, char const *s)
+{
+  char ip[16] ;
+  register unsigned int pos ;
+  if (flag6)
+  {
+    pos = ip6_scan(s, ip) ;
+    if (pos)
+    {
+      s6dns_domain_arpafromip6(d, ip, 128) ;
+      goto yes ;
+    }
+  }
+  if (flag4)
+  {
+    pos = ip4_scan(s, ip) ;
+    if (pos)
+    {
+      s6dns_domain_arpafromip4(d, ip) ;
+      goto yes ;
+    }
+  }
+  return 0 ;
+ yes:
+  if (!s6dns_domain_encode(d)) return 0 ;
+  return pos ;
+}
+
+typedef struct s6dns_domain1_s s6dns_domain1_t, *s6dns_domain1_t_ref ;
+struct s6dns_domain1_s
+{
+  s6dns_domain_t d ;
+  unsigned int got : 1 ;
+} ;
+
+static int s6dns_message_parse_answer_domain1 (s6dns_message_rr_t const *rr, char const *packet, unsigned int packetlen, unsigned int pos, unsigned int section, void *stuff)
+{
+  if ((section == 2) && (rr->rtype == S6DNS_T_PTR))
+  {
+    s6dns_domain1_t *data = stuff ;
+    register unsigned int start = pos ;
+    if (data->got) return 1 ;
+    if (!s6dns_message_get_domain(&data->d, packet, packetlen, &pos)) return 0 ;
+    if (rr->rdlength != pos - start) return (errno = EPROTO, 0) ;
+    data->got = 1 ;
+  }
+  return 1 ;
+}
+
+static int domainformatter (stralloc *sa, char const *packet, unsigned int packetlen)
+{
+  s6dns_domain1_t data ;
+  s6dns_message_header_t h ;
+  register int r ;
+  data.got = 0 ;
+  r = s6dns_message_parse(&h, packet, packetlen, &s6dns_message_parse_answer_domain1, &data) ;
+  if (r <= 0) return r ;
+  if (!data.got) return 1 ;
+  if (!stralloc_readyplus(sa, data.d.len + 1)) return -1 ;
+  sa->len += s6dns_domain_tostring(sa->s + sa->len, data.d.len + 1, &data.d) ;
+  stralloc_0(sa) ;
+  return 1 ;
+}
+
+int main (int argc, char const *const *argv, char const *const *envp)
+{
+  PROG = "s6-dnsname-filter" ;
+  return s6dns_generic_filter_main(argc, argv, envp, S6DNS_T_PTR, &ipscanner, &domainformatter, USAGE) ;
+}
diff --git a/src/clients/s6-dnsname.c b/src/clients/s6-dnsname.c
new file mode 100644
index 0000000..d65da3a
--- /dev/null
+++ b/src/clients/s6-dnsname.c
@@ -0,0 +1,75 @@
+/* ISC license. */
+
+#include <errno.h>
+#include <skalibs/sgetopt.h>
+#include <skalibs/strerr2.h>
+#include <skalibs/buffer.h>
+#include <skalibs/fmtscan.h>
+#include <skalibs/tai.h>
+#include <skalibs/genalloc.h>
+#include <skalibs/ip46.h>
+#include <skalibs/random.h>
+#include <skalibs/s6dns.h>
+
+#define USAGE "s6-dnsname [ -4 | -6 ] [ -r ] [ -t timeout ] ip"
+#define dieusage() strerr_dieusage(100, USAGE)
+
+int main (int argc, char const *const *argv)
+{
+  genalloc ds = GENALLOC_ZERO ; /* array of s6dns_domain_t */
+  tain_t deadline ;
+  ip46full_t ip = IP46FULL_ZERO ;
+  unsigned int i = 0 ;
+  int flagunsort = 0 ;
+  int do4 = 0 ;
+  int do6 = 0 ;
+  PROG = "s6-dnsname" ;
+  for (;;)
+  {
+    register int opt = subgetopt(argc, argv, "46rt:") ;
+    if (opt == -1) break ;
+    switch (opt)
+    {
+      case '4' : do4 = 1 ; break ;
+      case '6' : do6 = 1 ; break ;
+      case 'r' : flagunsort = 1 ; break ;
+      case 't' : if (!uint0_scan(subgetopt_here.arg, &i)) dieusage() ; break ;
+      default : dieusage() ;
+    }
+  }
+  argc -= subgetopt_here.ind ; argv += subgetopt_here.ind ;
+  if (argc < 1) dieusage() ;
+  if (!do4 && !do6) do4 = do6 = 1 ;
+  if (do4 && do6)
+  {
+    if (!ip46full_scan(argv[0], &ip)) dieusage() ;
+  }
+  else if (do6)
+  {
+    if (!ip6_scan(argv[0], ip.ip)) dieusage() ;
+    ip.is6 = 1 ;
+  }
+  else if (!ip4_scan(argv[0], ip.ip)) dieusage() ;
+  
+  tain_now_g() ;
+  if (i) tain_from_millisecs(&deadline, i) ; else deadline = tain_infinite_relative ;
+  tain_add_g(&deadline, &deadline) ;
+  if (!s6dns_init()) strerr_diefu1sys(111, "s6dns_init") ;
+  {
+    register int r = ip.is6 ? s6dns_resolve_name6_g(&ds, ip.ip, &deadline) : s6dns_resolve_name4_g(&ds, ip.ip, &deadline) ;
+    if (r < 0) strerr_diefu2sys((errno == ETIMEDOUT) ? 99 : 111, "resolve ", argv[0]) ;
+    if (!r) strerr_diefu4x(2, "resolve ", argv[0], ": ", s6dns_constants_error_str(errno)) ;
+  }
+  if (!genalloc_len(s6dns_domain_t, &ds)) return 1 ;
+  if (flagunsort) random_unsort(ds.s, genalloc_len(s6dns_domain_t, &ds), sizeof(s6dns_domain_t)) ;
+  {
+    char buf[S6DNS_FMT_DOMAINLIST(genalloc_len(s6dns_domain_t, &ds))] ;
+    unsigned int len = s6dns_fmt_domainlist(buf, S6DNS_FMT_DOMAINLIST(genalloc_len(s6dns_domain_t, &ds)), genalloc_s(s6dns_domain_t, &ds), genalloc_len(s6dns_domain_t, &ds), "\n", 1) ;
+    if (!len) strerr_diefu1sys(111, "format result") ;
+    if (buffer_putalign(buffer_1, buf, len) < 0) goto err ;
+  }
+  if (buffer_putflush(buffer_1, "\n", 1) < 0) goto err ;
+  return 0 ;
+ err:
+  strerr_diefu1sys(111, "write to stdout") ;
+}
diff --git a/src/clients/s6-dnsns.c b/src/clients/s6-dnsns.c
new file mode 100644
index 0000000..d1caba5
--- /dev/null
+++ b/src/clients/s6-dnsns.c
@@ -0,0 +1,61 @@
+/* ISC license. */
+
+#include <errno.h>
+#include <skalibs/uint.h>
+#include <skalibs/bytestr.h>
+#include <skalibs/sgetopt.h>
+#include <skalibs/strerr2.h>
+#include <skalibs/buffer.h>
+#include <skalibs/tai.h>
+#include <skalibs/genalloc.h>
+#include <skalibs/random.h>
+#include <s6-dns/s6dns.h>
+
+#define USAGE "s6-dnsns [ -q ] [ -r ] [ -t timeout ] name"
+#define dieusage() strerr_dieusage(100, USAGE)
+
+int main (int argc, char const *const *argv)
+{
+  genalloc ds = GENALLOC_ZERO ; /* array of s6dns_domain_t */
+  tain_t deadline ;
+  unsigned int i = 0 ;
+  int flagqualify = 0 ;
+  int flagunsort = 0 ;
+  PROG = "s6-dnsns" ;
+  for (;;)
+  {
+    register int opt = subgetopt(argc, argv, "qrt:") ;
+    if (opt == -1) break ;
+    switch (opt)
+    {
+      case 'q' : flagqualify = 1 ; break ;
+      case 'r' : flagunsort = 1 ; break ;
+      case 't' : if (!uint0_scan(subgetopt_here.arg, &i)) dieusage() ; break ;
+      default : dieusage() ;
+    }
+  }
+  argc -= subgetopt_here.ind ; argv += subgetopt_here.ind ;
+  if (argc < 1) dieusage() ;
+
+  tain_now_g() ;
+  if (i) tain_from_millisecs(&deadline, i) ; else deadline = tain_infinite_relative ;
+  tain_add_g(&deadline, &deadline) ;
+  if (!s6dns_init()) strerr_diefu1sys(111, "s6dns_init") ;
+  {
+    register int r = s6dns_resolve_ns_g(&ds, argv[0], str_len(argv[0]), flagqualify, &deadline) ;
+    if (r < 0) strerr_diefu2sys((errno == ETIMEDOUT) ? 99 : 111, "resolve ", argv[0]) ;
+    if (!r) strerr_diefu4x(2, "resolve ", argv[0], ": ", s6dns_constants_error_str(errno)) ;
+  }
+  if (!genalloc_len(s6dns_domain_t, &ds)) return 1 ;
+  if (flagunsort) random_unsort(ds.s, genalloc_len(s6dns_domain_t, &ds), sizeof(s6dns_domain_t)) ;
+  {
+    char buf[S6DNS_FMT_DOMAINLIST(genalloc_len(s6dns_domain_t, &ds))] ;
+    unsigned int len = s6dns_fmt_domainlist(buf, S6DNS_FMT_DOMAINLIST(genalloc_len(s6dns_domain_t, &ds)), genalloc_s(s6dns_domain_t, &ds), genalloc_len(s6dns_domain_t, &ds), "\n", 1) ;
+    if (!len) strerr_diefu1sys(111, "format result") ;
+    if (buffer_put(buffer_1, buf, len) < 0) goto err ;
+  }
+  if (buffer_putflush(buffer_1, "\n", 1) < 0) goto err ;
+  return 0 ;
+ err:
+  strerr_diefu1sys(111, "write to stdout") ;
+}
diff --git a/src/clients/s6-dnsq.c b/src/clients/s6-dnsq.c
new file mode 100644
index 0000000..76ca4ea
--- /dev/null
+++ b/src/clients/s6-dnsq.c
@@ -0,0 +1,99 @@
+/* ISC license. */
+
+#include <errno.h>
+#include <skalibs/uint16.h>
+#include <skalibs/uint32.h>
+#include <skalibs/uint.h>
+#include <skalibs/bytestr.h>
+#include <skalibs/bitarray.h>
+#include <skalibs/strerr2.h>
+#include <skalibs/sgetopt.h>
+#include <skalibs/buffer.h>
+#include <skalibs/genwrite.h>
+#include <skalibs/tai.h>
+#include <skalibs/ip46.h>
+#include <s6-dns/s6dns.h>
+#include <s6-dns/s6dns-analyze.h>
+#include <s6-dns/s6dns-debug.h>
+
+#define USAGE "s6-dnsq [ -1 | -2 ] [ -t timeout ] [ -D debuglevel ] qtype query serverip..."
+#define dieusage() strerr_dieusage(100, USAGE)
+
+int main (int argc, char const *const *argv)
+{
+  tain_t deadline ;
+  unsigned int debuglevel = 0 ;
+  uint16 qtype ;
+  genwrite_t *where = &genwrite_stderr ;
+  PROG = "s6-dnsq" ;
+  {
+    subgetopt_t l = SUBGETOPT_ZERO ;
+    unsigned int t = 0 ;
+    for (;;)
+    {
+      register int opt = subgetopt_r(argc, argv, "12t:D:", &l) ;
+      if (opt == -1) break ;
+      switch (opt)
+      {
+        case '1' : where = &genwrite_stdout ; break ;
+        case '2' : where = &genwrite_stderr ; break ;
+        case 't' : if (!uint0_scan(l.arg, &t)) dieusage() ; break ;
+        case 'D' : if (!uint0_scan(l.arg, &debuglevel)) dieusage() ; break ;
+        default : dieusage() ;
+      }
+    }
+    argc -= l.ind ; argv += l.ind ;
+    if (t) tain_from_millisecs(&deadline, t) ; else deadline = tain_infinite_relative ;
+  }
+  if (argc < 3) dieusage() ;
+  {
+    s6dns_debughook_t dbh = { .post_recv = 0, .pre_send = 0, .post_send = 0 } ;
+    s6dns_ip46list_t servers ;
+    s6dns_domain_t d ;
+    unsigned int i = 0, j = 0 ;
+    qtype = s6dns_analyze_qtype_parse(argv[0]) ;
+    if (!qtype) dieusage() ;
+    if (!s6dns_domain_fromstring_noqualify_encode(&d, argv[1], str_len(argv[1])))
+      strerr_diefu2sys(100, "encode ", argv[1]) ;
+    dbh.external = where ;
+    byte_zero(&servers, sizeof(s6dns_ip46list_t)) ;
+    for (; (i < (unsigned int)(argc - 2)) && (j < S6DNS_MAX_SERVERS) ; i++)
+    {
+      ip46_t z[S6DNS_MAX_SERVERS] ;
+      unsigned int n ;
+      register unsigned int k = 0 ;
+      if (!*argv[2+i]) continue ;
+      if (!ip46_scanlist(z, S6DNS_MAX_SERVERS - j, argv[2 + i], &n))
+        strerr_diefu2sys(100, "make an IP address list out of ", argv[2+i]) ;
+      for (; k < n ; k++)
+      {
+        byte_copy(s6dns_ip46list_ip(&servers, j + k), SKALIBS_IP_SIZE, z[k].ip) ;
+#ifdef SKALIBS_IPV6_ENABLED
+        if (ip46_is6(z + k)) bitarray_set(servers.is6, j + k) ;
+#endif
+      }
+      j += n ;
+    }
+    if (debuglevel & 1) dbh.post_recv = &s6dns_debug_dumpdt_post_recv ;
+    if (debuglevel & 2) { dbh.pre_send = &s6dns_debug_dumpdt_pre_send ; dbh.post_send = &s6dns_debug_dumpdt_post_send ; }
+    tain_now_g() ;
+    tain_add_g(&deadline, &deadline) ;
+    if (!s6dns_engine_init_r_g(&s6dns_engine_here, &servers, 0, d.s, d.len, qtype, &dbh, &deadline))
+      strerr_diefu1sys(111, "initialize query") ;
+  }
+  if (!s6dns_resolve_loop_g(&deadline))
+  {
+    char fmt[UINT16_FMT] ;
+    fmt[uint16_fmt(fmt, qtype)] = 0 ;
+    strerr_diefu6x((errno == ETIMEDOUT) ? 99 : 2, "resolve query ", argv[0], " of qtype ", fmt, ": ", s6dns_constants_error_str(errno)) ;
+  }
+  if (!s6dns_analyze_packet(&genwrite_stdout, s6dns_engine_packet(&s6dns_engine_here), s6dns_engine_packetlen(&s6dns_engine_here), 0))
+  {
+    int e = errno ;
+    buffer_flush(buffer_1) ;
+    errno = e ;
+    strerr_diefu1sys(111, "analyze response") ;
+  }
+  if (!buffer_flush(buffer_1)) strerr_diefu1sys(111, "write to stdout") ;
+  return 0 ;
+}
diff --git a/src/clients/s6-dnsqr.c b/src/clients/s6-dnsqr.c
new file mode 100644
index 0000000..1effe68
--- /dev/null
+++ b/src/clients/s6-dnsqr.c
@@ -0,0 +1,74 @@
+/* ISC license. */
+
+#include <errno.h>
+#include <skalibs/uint16.h>
+#include <skalibs/uint.h>
+#include <skalibs/bytestr.h>
+#include <skalibs/strerr2.h>
+#include <skalibs/sgetopt.h>
+#include <skalibs/buffer.h>
+#include <skalibs/genwrite.h>
+#include <skalibs/tai.h>
+#include <s6-dns/s6dns.h>
+#include <s6-dns/s6dns-analyze.h>
+#include <s6-dns/s6dns-debug.h>
+
+#define USAGE "s6-dnsqr [ -1 | -2 ] [ -t timeout ] [ -D debuglevel ] qtype query"
+#define dieusage() strerr_dieusage(100, USAGE)
+
+int main (int argc, char const *const *argv)
+{
+  tain_t deadline ;
+  unsigned int debuglevel = 0 ;
+  genwrite_t *where = &genwrite_stderr ;
+  PROG = "s6-dnsqr" ;
+  {
+    subgetopt_t l = SUBGETOPT_ZERO ;
+    unsigned int t = 0 ;
+    for (;;)
+    {
+      register int opt = subgetopt_r(argc, argv, "12t:D:", &l) ;
+      if (opt == -1) break ;
+      switch (opt)
+      {
+        case '1' : where = &genwrite_stdout ; break ;
+        case '2' : where = &genwrite_stderr ; break ;
+        case 't' : if (!uint0_scan(l.arg, &t)) dieusage() ; break ;
+        case 'D' : if (!uint0_scan(l.arg, &debuglevel)) dieusage() ; break ;
+        default : dieusage() ;
+      }
+    }
+    argc -= l.ind ; argv += l.ind ;
+    if (t) tain_from_millisecs(&deadline, t) ; else deadline = tain_infinite_relative ;
+  }
+  if (argc < 2) dieusage() ;
+  {
+    s6dns_debughook_t dbh = { .post_recv = 0, .pre_send = 0, .post_send = 0 } ;
+    s6dns_domain_t d ;
+    uint16 qtype = s6dns_analyze_qtype_parse(argv[0]) ;
+    if (!qtype) dieusage() ;
+    if (!s6dns_domain_fromstring_noqualify_encode(&d, argv[1], str_len(argv[1])))
+      strerr_diefu2sys(100, "encode ", argv[1]) ;
+    dbh.external = where ;
+    if (debuglevel & 1) dbh.post_recv = &s6dns_debug_dumpdt_post_recv ;
+    if (debuglevel & 2) { dbh.pre_send = &s6dns_debug_dumpdt_pre_send ; dbh.post_send = &s6dns_debug_dumpdt_post_send ; }
+    tain_now_g() ;
+    tain_add_g(&deadline, &deadline) ;
+    if (!s6dns_init()) strerr_diefu1sys(111, "s6dns_init") ;
+    if (!s6dns_resolve_core_r_g(&d, qtype, &s6dns_engine_here, &s6dns_rci_here.servers, &dbh, &deadline))
+    {
+      char fmt[UINT16_FMT] ;
+      fmt[uint16_fmt(fmt, qtype)] = 0 ;
+      strerr_diefu6x((errno == ETIMEDOUT) ? 99 : 2, "resolve query ", argv[1], " of qtype ", fmt, ": ", s6dns_constants_error_str(errno)) ;
+    }
+  }
+  if (!s6dns_analyze_packet(&genwrite_stdout, s6dns_engine_packet(&s6dns_engine_here), s6dns_engine_packetlen(&s6dns_engine_here), 1))
+  {
+    int e = errno ;
+    buffer_flush(buffer_1) ;
+    errno = e ;
+    strerr_diefu1sys(111, "analyze response") ;
+  }
+  if (!buffer_flush(buffer_1)) strerr_diefu1sys(111, "write to stdout") ;
+  return 0 ;
+}
diff --git a/src/clients/s6-dnsqualify.c b/src/clients/s6-dnsqualify.c
new file mode 100644
index 0000000..64767ae
--- /dev/null
+++ b/src/clients/s6-dnsqualify.c
@@ -0,0 +1,34 @@
+/* ISC license. */
+
+#include <skalibs/bytestr.h>
+#include <skalibs/strerr2.h>
+#include <skalibs/buffer.h>
+#include <s6-dns/s6dns.h>
+
+#define USAGE "s6-dnsqualify name"
+#define dieusage() strerr_dieusage(100, USAGE)
+
+int main (int argc, char const *const *argv)
+{
+  s6dns_domain_t d ;
+  PROG = "s6-dnsqualify" ;
+  if (argc < 2) dieusage() ;
+  if (!s6dns_domain_fromstring(&d, argv[1], str_len(argv[1])))
+    strerr_diefu2sys(100, "make a domain name from ", argv[1]) ;
+  if (!s6dns_init()) strerr_diefu1sys(111, "s6dns_init") ;
+  {
+    s6dns_domain_t list[s6dns_rci_here.rulesnum] ;
+    unsigned int n = s6dns_qualify(list, &d) ;
+    if (!n) strerr_diefu2sys(111, "qualify ", argv[1]) ;
+    {
+      char buf[S6DNS_FMT_DOMAINLIST(n)] ;
+      unsigned int len = s6dns_fmt_domainlist(buf, S6DNS_FMT_DOMAINLIST(n), list, n, "\n", 1) ;
+      if (!len) strerr_diefu1sys(111, "format result") ;
+      if (buffer_put(buffer_1, buf, len) < 0) goto err ;
+    }
+  }
+  if (buffer_putflush(buffer_1, "\n", 1) < 0) goto err ;
+  return 0 ;
+ err:
+  strerr_diefu1sys(111, "write to stdout") ;
+}
diff --git a/src/clients/s6-dnssoa.c b/src/clients/s6-dnssoa.c
new file mode 100644
index 0000000..1b02ff6
--- /dev/null
+++ b/src/clients/s6-dnssoa.c
@@ -0,0 +1,63 @@
+/* ISC license. */
+
+#include <errno.h>
+#include <skalibs/uint.h>
+#include <skalibs/bytestr.h>
+#include <skalibs/sgetopt.h>
+#include <skalibs/strerr2.h>
+#include <skalibs/buffer.h>
+#include <skalibs/tai.h>
+#include <skalibs/genalloc.h>
+#include <skalibs/random.h>
+#include <s6-dns/s6dns.h>
+
+#define USAGE "s6-dnssoa [ -q ] [ -r ] [ -t timeout ] name"
+#define dieusage() strerr_dieusage(100, USAGE)
+
+int main (int argc, char const *const *argv)
+{
+  genalloc soas = GENALLOC_ZERO ; /* array of s6dns_message_rr_soa_t */
+  tain_t deadline ;
+  unsigned int i = 0 ;
+  int flagqualify = 0 ;
+  int flagunsort = 0 ;
+  PROG = "s6-dnssoa" ;
+  for (;;)
+  {
+    register int opt = subgetopt(argc, argv, "qrt:") ;
+    if (opt == -1) break ;
+    switch (opt)
+    {
+      case 'q' : flagqualify = 1 ; break ;
+      case 'r' : flagunsort = 1 ; break ;
+      case 't' : if (!uint0_scan(subgetopt_here.arg, &i)) dieusage() ; break ;
+      default : dieusage() ;
+    }
+  }
+  argc -= subgetopt_here.ind ; argv += subgetopt_here.ind ;
+  if (argc < 1) dieusage() ;
+
+  tain_now_g() ;
+  if (i) tain_from_millisecs(&deadline, i) ; else deadline = tain_infinite_relative ;
+  tain_add_g(&deadline, &deadline) ;
+  if (!s6dns_init()) strerr_diefu1sys(111, "s6dns_init") ;
+  {
+    register int r = s6dns_resolve_soa_g(&soas, argv[0], str_len(argv[0]), flagqualify, &deadline) ;
+    if (r < 0) strerr_diefu2sys((errno == ETIMEDOUT) ? 99 : 111, "resolve ", argv[0]) ;
+    if (!r) strerr_diefu4x(2, "resolve ", argv[0], ": ", s6dns_constants_error_str(errno)) ;
+  }
+  if (!genalloc_len(s6dns_message_rr_soa_t, &soas)) return 1 ;
+  if (flagunsort) random_unsort(soas.s, genalloc_len(s6dns_message_rr_soa_t, &soas), sizeof(s6dns_message_rr_soa_t)) ;
+  for (i = 0 ; i < genalloc_len(s6dns_message_rr_soa_t, &soas) ; i++)
+  {
+    char buf[S6DNS_FMT_SOA] ;
+    register unsigned int len = s6dns_fmt_soa(buf, S6DNS_FMT_SOA, genalloc_s(s6dns_message_rr_soa_t, &soas) + i) ;
+    if (!len) strerr_diefu1sys(111, "format result") ;
+    if (buffer_put(buffer_1, buf, len) < 0) goto err ;
+    if (buffer_put(buffer_1, "\n", 1) < 0) goto err ;
+  }
+  if (!buffer_flush(buffer_1)) goto err ;
+  return 0 ;
+ err:
+  strerr_diefu1sys(111, "write to stdout") ;
+}
diff --git a/src/clients/s6-dnssrv.c b/src/clients/s6-dnssrv.c
new file mode 100644
index 0000000..283f1cd
--- /dev/null
+++ b/src/clients/s6-dnssrv.c
@@ -0,0 +1,75 @@
+/* ISC license. */
+
+#include <errno.h>
+#include <skalibs/uint.h>
+#include <skalibs/bytestr.h>
+#include <skalibs/sgetopt.h>
+#include <skalibs/strerr2.h>
+#include <skalibs/buffer.h>
+#include <skalibs/tai.h>
+#include <skalibs/genalloc.h>
+#include <skalibs/random.h>
+#include <s6-dns/s6dns.h>
+
+#define USAGE "s6-dnssrv [ -q ] [ -r ] [ -t timeout ] service protocol name"
+#define dieusage() strerr_dieusage(100, USAGE)
+
+int main (int argc, char const *const *argv)
+{
+  genalloc srvs = GENALLOC_ZERO ; /* array of s6dns_message_rr_srv_t */
+  tain_t deadline ;
+  unsigned int i = 0 ;
+  int flagqualify = 0 ;
+  int flagunsort = 0 ;
+  PROG = "s6-dnssrv" ;
+  for (;;)
+  {
+    register int opt = subgetopt(argc, argv, "qt:") ;
+    if (opt == -1) break ;
+    switch (opt)
+    {
+      case 'q' : flagqualify = 1 ; break ;
+      case 'r' : flagunsort = 1 ; break ;
+      case 't' : if (!uint0_scan(subgetopt_here.arg, &i)) dieusage() ; break ;
+      default : dieusage() ;
+    }
+  }
+  argc -= subgetopt_here.ind ; argv += subgetopt_here.ind ;
+  if (argc < 3) dieusage() ;
+
+  tain_now_g() ;
+  if (i) tain_from_millisecs(&deadline, i) ; else deadline = tain_infinite_relative ;
+  tain_add_g(&deadline, &deadline) ;
+  if (!s6dns_init()) strerr_diefu1sys(111, "s6dns_init") ;
+  {
+    unsigned int n0 = str_len(argv[0]) ;
+    unsigned int n1 = str_len(argv[1]) ;
+    unsigned int n2 = str_len(argv[2]) ;
+    char name[n0 + n1 + n2 + 5] ;
+    name[0] = '_' ;
+    byte_copy(name + 1, n0, argv[0]) ;
+    name[n0 + 1] = '.' ;
+    name[n0 + 2] = '_' ;
+    byte_copy(name + n0 + 3, n1, argv[1]) ;
+    name[n0 + n1 + 3] = '.' ;
+    byte_copy(name + n0 + n1 + 4, n2, argv[2]) ;
+    name[n0 + n1 + n2 + 4] = 0 ;
+    register int r = s6dns_resolve_srv_g(&srvs, name, n0 + n1 + n2 + 4, flagqualify, &deadline) ;
+    if (r < 0) strerr_diefu2sys((errno == ETIMEDOUT) ? 99 : 111, "resolve ", argv[0]) ;
+    if (!r) strerr_diefu4x(2, "resolve ", name, ": ", s6dns_constants_error_str(errno)) ;
+  }
+  if (!genalloc_len(s6dns_message_rr_srv_t, &srvs)) return 1 ;
+  if (flagunsort) random_unsort(srvs.s, genalloc_len(s6dns_message_rr_srv_t, &srvs), sizeof(s6dns_message_rr_srv_t)) ;
+  for (i = 0 ; i < genalloc_len(s6dns_message_rr_srv_t, &srvs) ; i++)
+  {
+    char buf[S6DNS_FMT_SRV] ;
+    register unsigned int len = s6dns_fmt_srv(buf, S6DNS_FMT_SRV, genalloc_s(s6dns_message_rr_srv_t, &srvs) + i) ;
+    if (!len) strerr_diefu1sys(111, "format result") ;
+    if (buffer_put(buffer_1, buf, len) < 0) goto err ;
+    if (buffer_put(buffer_1, "\n", 1) < 0) goto err ;
+  }
+  if (!buffer_flush(buffer_1)) goto err ;
+  return 0 ;
+ err:
+  strerr_diefu1sys(111, "write to stdout") ;
+}
diff --git a/src/clients/s6-dnstxt.c b/src/clients/s6-dnstxt.c
new file mode 100644
index 0000000..fde69d2
--- /dev/null
+++ b/src/clients/s6-dnstxt.c
@@ -0,0 +1,78 @@
+/* ISC license. */
+
+#include <errno.h>
+#include <skalibs/uint.h>
+#include <skalibs/bytestr.h>
+#include <skalibs/sgetopt.h>
+#include <skalibs/strerr2.h>
+#include <skalibs/buffer.h>
+#include <skalibs/tai.h>
+#include <skalibs/stralloc.h>
+#include <skalibs/genalloc.h>
+#include <skalibs/skamisc.h>
+#include <skalibs/random.h>
+#include <s6-dns/s6dns.h>
+
+#define USAGE "s6-dnstxt [ -q ] [ -r ] [ -t timeout ] name"
+#define dieusage() strerr_dieusage(100, USAGE)
+
+int main (int argc, char const *const *argv)
+{
+  stralloc quoted = STRALLOC_ZERO ;
+  stralloc sa = STRALLOC_ZERO ;
+  genalloc offsets = GENALLOC_ZERO ; /* array of unsigned int */
+  tain_t deadline, stamp ;
+  unsigned int n ;
+  unsigned int i = 0 ;
+  int flagqualify = 0 ;
+  int flagunsort = 0 ;
+  PROG = "s6-dnstxt" ;
+  for (;;)
+  {
+    register int opt = subgetopt(argc, argv, "qrt:") ;
+    if (opt == -1) break ;
+    switch (opt)
+    {
+      case 'q' : flagqualify = 1 ; break ;
+      case 'r' : flagunsort = 1 ; break ;
+      case 't' : if (!uint0_scan(subgetopt_here.arg, &i)) dieusage() ; break ;
+      default : dieusage() ;
+    }
+  }
+  argc -= subgetopt_here.ind ; argv += subgetopt_here.ind ;
+  if (argc < 1) dieusage() ;
+
+  tain_now(&stamp) ;
+  if (i) tain_from_millisecs(&deadline, i) ; else deadline = tain_infinite_relative ;
+  tain_add(&deadline, &deadline, &stamp) ;
+  if (!s6dns_init()) strerr_diefu1sys(111, "s6dns_init") ;
+  {
+    register int r = s6dns_resolve_txt(&sa, &offsets, argv[0], str_len(argv[0]), flagqualify, &deadline, &stamp) ;
+    if (r < 0) strerr_diefu2sys((errno == ETIMEDOUT) ? 99 : 111, "resolve ", argv[0]) ;
+    if (!r) strerr_diefu4x(2, "resolve ", argv[0], ": ", s6dns_constants_error_str(errno)) ;
+  }
+  n = genalloc_len(unsigned int, &offsets) ;
+  if (!n) return 1 ;
+  {
+    unsigned int printable_offsets[n] ;
+    for (i = 0 ; i < n ; i++)
+    {
+      unsigned int beg = genalloc_s(unsigned int, &offsets)[i] ;
+      unsigned int end = (i < n-1 ? genalloc_s(unsigned int, &offsets)[i+1] : sa.len) - 1 ;
+      printable_offsets[i] = quoted.len ;
+      if (!string_quote(&quoted, sa.s + beg, end - beg) || !stralloc_0(&quoted))
+        strerr_diefu2sys(111, "quote ", sa.s + beg) ;
+    }
+    genalloc_free(unsigned int, &offsets) ;
+    stralloc_free(&sa) ;
+    if (flagunsort) random_unsort((char *)printable_offsets, n, sizeof(unsigned int)) ;
+    for (i = 0 ; i < n ; i++)
+      if ((buffer_puts(buffer_1small, quoted.s + printable_offsets[i]) < 0)
+       || (buffer_put(buffer_1small, "\n", 1) < 1))
+        strerr_diefu1sys(111, "write to stdout") ;
+  }
+  stralloc_free(&quoted) ;
+  if (!buffer_flush(buffer_1small))
+    strerr_diefu1sys(111, "write to stdout") ;
+  return 0 ;
+}
diff --git a/src/clients/s6-randomip.c b/src/clients/s6-randomip.c
new file mode 100644
index 0000000..b220374
--- /dev/null
+++ b/src/clients/s6-randomip.c
@@ -0,0 +1,62 @@
+/* ISC license. */
+
+#include <errno.h>
+#include <skalibs/uint.h>
+#include <skalibs/sgetopt.h>
+#include <skalibs/strerr2.h>
+#include <skalibs/buffer.h>
+#include <skalibs/fmtscan.h>
+#include <skalibs/random.h>
+
+#define USAGE "s6-randomip [ -4 ] [ -6 ] [ -n number ]"
+#define dieusage() strerr_dieusage(100, USAGE)
+
+int main (int argc, char const *const *argv)
+{
+  char fmt[IP6_FMT] ;
+  char ip[16] ;
+  unsigned int n ;
+  unsigned int i = 0 ;
+  unsigned int what = 0 ;
+  int finite = 0 ;
+  PROG = "s6-randomip" ;
+  for (;;)
+  {
+    register int opt = subgetopt(argc, argv, "46n:") ;
+    if (opt == -1) break ;
+    switch (opt)
+    {
+      case '4' : what |= 1 ; break ;
+      case '6' : what |= 2 ; break ;
+      case 'n' :
+        if (!uint0_scan(subgetopt_here.arg, &n)) dieusage() ;
+        finite = 1 ;
+        break ;
+      default : dieusage() ;
+    }
+  }
+  argc -= subgetopt_here.ind ; argv += subgetopt_here.ind ;
+  if (!what) what = 1 ;
+  what = 1 << (1 << what) ; 
+  if (!badrandom_init()) strerr_diefu1sys(111, "init RNG") ;
+  for (i = 0 ; !finite || (i < n) ; i++)
+  {
+    unsigned int len = what ;
+    if (len > 16)
+    {
+      char c ;
+      if (badrandom_string(&c, 1) < 1)
+        strerr_diefu1sys(111, "badrandom_string") ;
+      len = (c & 1) ? 16 : 4 ;
+    }
+    if (badrandom_string(ip, len) < 4)
+      strerr_diefu1sys(111, "badrandom_string") ;
+    len = (len == 16) ? ip6_fmt(fmt, ip) : ip4_fmt(fmt, ip) ;
+    fmt[len++] = '\n' ;
+    if (buffer_put(buffer_1, fmt, len) < (int)len)
+      strerr_diefu1sys(111, "write to stdout") ;
+  }
+  if (!buffer_flush(buffer_1))
+    strerr_diefu1sys(111, "write to stdout") ;
+  return 0 ;
+}
diff --git a/src/clients/s6dns-generic-filter.h b/src/clients/s6dns-generic-filter.h
new file mode 100644
index 0000000..53fa560
--- /dev/null
+++ b/src/clients/s6dns-generic-filter.h
@@ -0,0 +1,22 @@
+/* ISC license. */
+
+#ifndef SKADNS_GENERIC_FILTER_H
+#define SKADNS_GENERIC_FILTER_H
+
+#include <skalibs/uint16.h>
+#include <skalibs/stralloc.h>
+#include <s6-dns/s6dns-domain.h>
+
+typedef unsigned int scan_func_t (s6dns_domain_t *, char const *) ;
+typedef scan_func_t *scan_func_t_ref ;
+typedef int fmt_func_t (stralloc *, char const *, unsigned int) ;
+typedef fmt_func_t *fmt_func_t_ref ;
+
+extern unsigned int s6dns_namescanner (s6dns_domain_t *, char const *) ;
+extern int s6dns_domainformatter (stralloc *, char const *, unsigned int) ;
+extern int s6dns_generic_filter_main (int, char const *const *, char const *const *, uint16, scan_func_t_ref, fmt_func_t_ref, char const *) ;
+
+extern int flag4 ;
+extern int flag6 ;
+
+#endif
diff --git a/src/clients/s6dns_generic_filter_main.c b/src/clients/s6dns_generic_filter_main.c
new file mode 100644
index 0000000..430b0c3
--- /dev/null
+++ b/src/clients/s6dns_generic_filter_main.c
@@ -0,0 +1,230 @@
+/* ISC license. */
+
+#include <errno.h>
+#include <skalibs/error.h>
+#include <skalibs/uint16.h>
+#include <skalibs/uint.h>
+#include <skalibs/sgetopt.h>
+#include <skalibs/strerr2.h>
+#include <skalibs/env.h>
+#include <skalibs/tai.h>
+#include <skalibs/iopause.h>
+#include <skalibs/djbunix.h>
+#include <skalibs/stralloc.h>
+#include <skalibs/buffer.h>
+#include <skalibs/bufalloc.h>
+#include <skalibs/skamisc.h>
+#include <s6-dns/s6dns-constants.h>
+#include <s6-dns/s6dns-domain.h>
+#include <s6-dns/skadns.h>
+#include "s6dns-generic-filter.h"
+
+#define dieusage() strerr_dief1x(100, USAGE) ;
+
+typedef struct line_s line_t, *line_t_ref ;
+struct line_s
+{
+  stralloc swrd ;
+  unsigned int wpos ;
+  int dpos ;
+  char w[2] ;
+  unsigned int pending : 1 ;
+} ;
+
+#define LINE_ZERO { STRALLOC_ZERO, 0, 0, "\0", 0 }
+
+static void line_recycle (line_t_ref l)
+{
+  l->swrd.len = 0 ;
+  l->pending = 0 ;
+}
+
+int flag4 = 0 ;
+int flag6 = 0 ;
+
+int s6dns_generic_filter_main (int argc, char const *const *argv, char const *const *envp, uint16 qtype, scan_func_t_ref scanner, fmt_func_t_ref formatter, char const *USAGE)
+{
+  skadns_t a = SKADNS_ZERO ;
+  tain_t deadline, tto ;
+  char const *normalformat = "%s=%d%w%r" ;
+  char const *errorformat = "%s=<%e>%w%r" ;
+  uint16 maxlines = 256 ;
+  uint16 maxconn = 128 ;
+  {
+    subgetopt_t l = SUBGETOPT_ZERO ;
+    unsigned int t = 0 ;
+    for (;;)
+    {
+      register int opt = subgetopt_r(argc, argv, (qtype == S6DNS_T_PTR) ? "46l:c:t:f:e:" : "l:c:t:f:e:", &l) ;
+      if (opt == -1) break ;
+      switch (opt)
+      {
+        case '4' : flag4 = 1 ; break ;
+        case '6' : flag6 = 1 ; break ;
+        case 'l' : if (!uint160_scan(l.arg, &maxlines)) dieusage() ; break ;
+        case 'c' : if (!uint160_scan(l.arg, &maxconn)) dieusage() ; break ;
+        case 't' : if (!uint0_scan(l.arg, &t)) dieusage() ; break ;
+        case 'f' : normalformat = l.arg ; break ;
+        case 'e' : errorformat = l.arg ; break ;
+        default : dieusage() ;
+      }
+    }
+    argc -= l.ind ; argv += l.ind ;
+    if (t) tain_from_millisecs(&tto, t) ; else tto = tain_infinite_relative ;
+  }
+  if (!flag4 && !flag6) flag4 = 1 ;
+  if (maxconn < 1) maxconn = 1 ;
+  if (maxconn > SKADNS_MAXCONCURRENCY) maxconn = SKADNS_MAXCONCURRENCY ;
+  if (maxlines < maxconn) maxlines = maxconn ;
+
+  tain_now_g() ;
+  tain_addsec_g(&deadline, 2) ;
+  if (!skadns_startf_g(&a, &deadline))
+    strerr_diefu1sys(111, "establish skadns connection") ;
+  if ((ndelay_on(0) < 0) || (ndelay_on(1) < 0))
+    strerr_diefu1sys(111, "ndelay_on") ;
+
+  {
+    iopause_fd x[3] = { { 0, 0, 0 }, { 1, 0, 0 }, { -1, 0, 0 } } ;
+    uint16 lhead = 0, ltail = 0, numlines = 0, pending = 0 ;
+    line_t storage[maxlines+1] ;
+    uint16 lineindex[maxconn] ;
+    x[2].fd = skadns_fd(&a) ;
+    {
+      line_t line_zero = LINE_ZERO ;
+      char const *args[4] = { "", "", "", "" } ;
+      uint16 i = 0 ;
+      for (; i <= maxlines ; i++) storage[i] = line_zero ;
+      if (!string_format(&storage[0].swrd, "sdwr", normalformat, args)
+       || !string_format(&storage[0].swrd, "sewr", errorformat, args))
+        strerr_diefu1sys(111, "format a string") ;
+      storage[0].swrd.len = 0 ;
+    }
+
+    for (;;)
+    {
+      x[0].events = !x[0].fd && (numlines < maxlines) && (pending < maxconn) ? IOPAUSE_READ : 0 ;
+      x[1].events = bufalloc_len(bufalloc_1) ? IOPAUSE_WRITE : 0 ;
+      x[2].events = pending ? IOPAUSE_READ : 0 ;
+      if (!x[0].events && !x[1].events && !x[2].events) break ;
+      tain_add_g(&deadline, &tain_infinite_relative) ;
+
+      if (iopause_g(x + !(x[0].events & IOPAUSE_READ), 3 - !(x[0].events & IOPAUSE_READ), &deadline) < 0)
+        strerr_diefu1sys(111, "iopause") ;
+
+
+     /* Flush stdout */
+
+      if (x[1].revents)
+      {
+        if (!bufalloc_flush(bufalloc_1) && !error_isagain(errno))
+          strerr_diefu1sys(111, "write to stdout") ;
+      }
+
+
+     /* Get and format results from skadnsd */
+
+      if (x[2].revents)
+      {
+	register int j = 0 ;
+        register uint16 const *list ;
+        int n = skadns_update(&a) ;
+        if (n < 0) strerr_diefu1sys(111, "skadns_update") ;
+        list = skadns_list(&a) ;
+        for (; j < n ; j++)
+        {
+          register uint16 i = lineindex[list[j]] ;
+          register char const *packet = skadns_packet(&a, list[j]) ;
+          if (packet)
+          {
+            register int r ;
+            r = (*formatter)(&storage[i].swrd, packet, skadns_packetlen(&a, list[j])) ;
+            if (r < 0) strerr_diefu1sys(111, "format skadns answer") ;
+            if (!r) storage[i].dpos = -errno ;
+          }
+          else storage[i].dpos = -errno ;
+          storage[i].pending = 0 ;
+          skadns_release(&a, list[j]) ;
+          pending-- ;
+        }
+        skadns_clearlist(&a) ;
+      }
+
+
+     /* Scan stdin and send queries to skadnsd */
+
+      if (buffer_len(buffer_0) || (!x[0].fd && x[0].revents))
+      {
+        for (; (numlines < maxlines) && (pending < maxconn) ; lhead = (lhead+1) % (maxlines+1), numlines++)
+        {
+          s6dns_domain_t d ;
+          register line_t_ref line = storage + lhead ;
+          register int r = skagetln(buffer_0, &line->swrd, '\n') ;
+          if (r < 0)
+          {
+            if (error_isagain(errno)) break ;
+            if (errno != EPIPE) strerr_diefu1sys(111, "read from stdin") ;
+            if (!stralloc_catb(&line->swrd, "\n", 1)) strerr_diefu1sys(111, "stralloc_catb") ;
+            x[0].fd = -1 ;
+            break ;
+          }
+          else if (!r)
+          {
+            x[0].fd = -1 ;
+            break ;
+          }
+          line->swrd.s[line->swrd.len-1] = 0 ;
+          line->wpos = (*scanner)(&d, line->swrd.s) ;
+          if (!line->wpos)
+          {
+            line->wpos = line->swrd.len - 1 ;
+            line->w[0] = 0 ;
+            line->dpos = -errno ;
+          }
+          else
+          {
+            tain_t sendlimit ;
+            uint16 id ;
+            line->w[0] = line->swrd.s[line->wpos] ;
+            line->swrd.s[line->wpos] = 0 ;
+            tain_addsec_g(&sendlimit, 2) ;
+            tain_add_g(&deadline, &tto) ;
+            if (!skadns_send_g(&a, &id, &d, qtype, &deadline, &sendlimit))
+              line->dpos = -errno ;
+            else
+            {
+              line->dpos = line->swrd.len ;
+              lineindex[id] = lhead ;
+              line->pending = 1 ;
+              pending++ ;
+            }
+          }
+        }
+      }
+
+      if (x[0].revents & IOPAUSE_EXCEPT) x[0].fd = -1 ;
+
+
+     /* Send processed lines to stdout */
+
+      for (; ltail != lhead ; ltail = (ltail+1) % (maxlines+1), numlines--)
+      {
+        char *args[4] ;
+        register line_t_ref line = storage + ltail ;
+        if (line->pending) break ;
+        args[0] = line->swrd.s ;
+        args[1] = line->dpos < 0 ? (char *)s6dns_constants_error_str(-line->dpos) : line->swrd.s + line->dpos ;
+        args[2] = line->w ;
+        args[3] = line->swrd.s + line->wpos + !!line->w[0] ;
+        if (!string_format(&bufalloc_1->x, line->dpos < 0 ? "sewr" : "sdwr", line->dpos < 0 ? errorformat : normalformat, (char const **)args))
+          strerr_diefu1sys(111, "format output line") ;
+        line_recycle(line) ;
+        if (!bufalloc_put(bufalloc_1, "\n", 1))
+          strerr_diefu1sys(111, "bufalloc_put") ;
+      }
+    }
+  }
+
+  (void)envp ;
+  return 0 ;
+}
diff --git a/src/clients/s6dns_namescanner.c b/src/clients/s6dns_namescanner.c
new file mode 100644
index 0000000..b23fb3d
--- /dev/null
+++ b/src/clients/s6dns_namescanner.c
@@ -0,0 +1,12 @@
+/* ISC license. */
+
+#include <s6-dns/s6dns-domain.h>
+#include <s6-dns/s6dns-generic-filter.h>
+
+unsigned int s6dns_namescanner (s6dns_domain_t *d, char const *s)
+{
+  register unsigned int pos = 0 ;
+  while (s[pos] && (s[pos] != ' ') && (s[pos] != '\t') && (s[pos] != '\r') && (s[pos] != '\n')) pos++ ;
+  if (!s6dns_domain_fromstring_noqualify_encode(d, s, pos)) return 0 ;
+  return pos ;
+}
diff --git a/src/include/s6-dns/s6dns-analyze.h b/src/include/s6-dns/s6dns-analyze.h
new file mode 100644
index 0000000..2908763
--- /dev/null
+++ b/src/include/s6-dns/s6dns-analyze.h
@@ -0,0 +1,39 @@
+/* ISC license. */
+
+#ifndef S6DNS_ANALYZE_H
+#define S6DNS_ANALYZE_H
+
+#include <skalibs/uint16.h>
+#include <skalibs/genwrite.h>
+#include <s6-dns/s6dns-message.h>
+
+typedef int s6dns_analyze_record_func_t (genwrite_t *, s6dns_message_rr_t const *, char const *, unsigned int, unsigned int) ;
+typedef s6dns_analyze_record_func_t *s6dns_analyze_record_func_t_ref ;
+
+typedef struct s6dns_analyze_rtypetable_s s6dns_analyze_rtypetable_t, *s6dns_analyze_rtypetable_t_ref ;
+struct s6dns_analyze_rtypetable_s
+{
+  uint16 rtype ;
+  char const *string ;
+  s6dns_analyze_record_func_t_ref f ;
+} ;
+
+extern uint16 s6dns_analyze_qtype_parse (char const *) ;
+
+extern s6dns_analyze_rtypetable_t const *s6dns_analyze_rtypetable ;
+
+extern s6dns_analyze_record_func_t s6dns_analyze_record_a ;
+extern s6dns_analyze_record_func_t s6dns_analyze_record_aaaa ;
+extern s6dns_analyze_record_func_t s6dns_analyze_record_hinfo ;
+extern s6dns_analyze_record_func_t s6dns_analyze_record_soa ;
+extern s6dns_analyze_record_func_t s6dns_analyze_record_mx ;
+extern s6dns_analyze_record_func_t s6dns_analyze_record_srv ;
+extern s6dns_analyze_record_func_t s6dns_analyze_record_domain ;
+extern s6dns_analyze_record_func_t s6dns_analyze_record_strings ;
+extern s6dns_analyze_record_func_t s6dns_analyze_record_unknown ;
+
+extern s6dns_analyze_record_func_t s6dns_analyze_record ;
+
+extern int s6dns_analyze_packet (genwrite_t *, char const *, unsigned int, int) ;
+
+#endif
diff --git a/src/include/s6-dns/s6dns-constants.h b/src/include/s6-dns/s6dns-constants.h
new file mode 100644
index 0000000..ad47dc1
--- /dev/null
+++ b/src/include/s6-dns/s6dns-constants.h
@@ -0,0 +1,52 @@
+/* ISC license. */
+
+#ifndef S6DNS_CONSTANTS_H
+#define S6DNS_CONSTANTS_H
+
+#include <skalibs/ip46.h>
+
+#define S6DNS_MAX_SERVERS 16U
+
+#define S6DNS_C_IN 0x0001U
+#define S6DNS_C_ANY 0x00ffU
+
+#define S6DNS_T_A 1U
+#define S6DNS_T_NS 2U
+#define S6DNS_T_CNAME 5U
+#define S6DNS_T_SOA 6U
+#define S6DNS_T_PTR 12U
+#define S6DNS_T_HINFO 13U
+#define S6DNS_T_MX 15U
+#define S6DNS_T_TXT 16U
+#define S6DNS_T_RP 17U
+#define S6DNS_T_SIG 24U
+#define S6DNS_T_KEY 25U
+#define S6DNS_T_AAAA 28U
+#define S6DNS_T_SRV 33U
+#define S6DNS_T_AXFR 252U
+#define S6DNS_T_ANY 255U
+
+#define S6DNS_O_RECURSIVE 0x0001U
+#define S6DNS_O_STRICT 0x0002U
+
+#define S6DNS_W_AND 0
+#define S6DNS_W_OR 1
+#define S6DNS_W_BEST 2
+
+typedef struct s6dns_constants_error_message_s s6dns_constants_error_message_t, *s6dns_constants_error_message_t_ref ;
+struct s6dns_constants_error_message_s
+{
+  int num ;
+  char const *string ;
+} ;
+
+extern s6dns_constants_error_message_t const *const s6dns_constants_error ;
+extern char const *s6dns_constants_error_str (int) ;
+
+#ifdef SKALIBS_IPV6_ENABLED
+# define S6DNS_LOCALHOST_IP IP6_LOCAL
+#else
+# define S6DNS_LOCALHOST_IP "\177\0\0\1"
+#endif
+
+#endif
diff --git a/src/include/s6-dns/s6dns-debug.h b/src/include/s6-dns/s6dns-debug.h
new file mode 100644
index 0000000..acc5818
--- /dev/null
+++ b/src/include/s6-dns/s6dns-debug.h
@@ -0,0 +1,16 @@
+/* ISC license. */
+
+#ifndef S6DNS_DEBUG_H
+#define S6DNS_DEBUG_H
+
+#include <s6-dns/s6dns-engine.h>
+
+extern s6dns_debughook_func_t s6dns_debug_dumpdt_post_recv ;
+extern s6dns_debughook_func_t s6dns_debug_dumpdt_pre_send ;
+extern s6dns_debughook_func_t s6dns_debug_dumpdt_post_send ;
+
+#define S6DNS_DEBUG_DUMPDT_INIT(gp) { &s6dns_debug_dumpdt_post_recv, &s6dns_debug_dumpdt_pre_send, &s6dns_debug_dumpdt_post_send, (gp) }
+extern s6dns_debughook_t const s6dns_debug_dumpdt_stdout ;
+extern s6dns_debughook_t const s6dns_debug_dumpdt_stderr ;
+
+#endif
diff --git a/src/include/s6-dns/s6dns-domain.h b/src/include/s6-dns/s6dns-domain.h
new file mode 100644
index 0000000..3faae07
--- /dev/null
+++ b/src/include/s6-dns/s6dns-domain.h
@@ -0,0 +1,47 @@
+/* ISC license. */
+
+#ifndef S6DNS_DOMAIN_H
+#define S6DNS_DOMAIN_H
+
+#include <skalibs/ip46.h>
+
+typedef struct s6dns_domain_s s6dns_domain_t, *s6dns_domain_t_ref ;
+struct s6dns_domain_s
+{
+  unsigned char len ;
+  char s[255] ;
+} ;
+
+
+ /* Conversions from/to user strings */
+
+extern int s6dns_domain_fromstring (s6dns_domain_t_ref, char const *, unsigned int) ;
+extern unsigned int s6dns_domain_tostring (char *, unsigned int, s6dns_domain_t const *) ;
+
+
+ /* Qualification */
+
+extern int s6dns_domain_noqualify (s6dns_domain_t_ref) ;
+extern unsigned int s6dns_domain_qualify (s6dns_domain_t *, s6dns_domain_t const *, char const *, unsigned int) ;
+
+
+ /* Internal coding/encoding to/from protocol form */
+
+extern int s6dns_domain_encode (s6dns_domain_t_ref) ;
+extern unsigned int s6dns_domain_encodelist (s6dns_domain_t_ref, unsigned int) ;
+extern int s6dns_domain_decode (s6dns_domain_t_ref) ;
+
+
+ /* Useful shortcuts */
+
+extern int s6dns_domain_fromstring_noqualify_encode (s6dns_domain_t_ref, char const *, unsigned int) ;
+extern unsigned int s6dns_domain_fromstring_qualify_encode (s6dns_domain_t *, char const *, unsigned int, char const *, unsigned int) ;
+
+
+ /* Helpers for PTR */
+
+extern void s6dns_domain_arpafromip4 (s6dns_domain_t_ref, char const *) ;
+extern void s6dns_domain_arpafromip6 (s6dns_domain_t_ref, char const *, unsigned int) ;
+#define s6dns_domain_arpafromip46(d, i) (ip46_is6(i) ? s6dns_domain_arpafromip6(d, (i)->ip, 128) : s6dns_domain_arpafromip4(d, (i)->ip))
+
+#endif
diff --git a/src/include/s6-dns/s6dns-engine.h b/src/include/s6-dns/s6dns-engine.h
new file mode 100644
index 0000000..d6b0503
--- /dev/null
+++ b/src/include/s6-dns/s6dns-engine.h
@@ -0,0 +1,108 @@
+/* ISC license. */
+
+#ifndef S6DNS_ENGINE_H
+#define S6DNS_ENGINE_H
+
+#include <errno.h>
+#include <skalibs/uint16.h>
+#include <skalibs/uint32.h>
+#include <skalibs/tai.h>
+#include <skalibs/stralloc.h>
+#include <s6-dns/s6dns-constants.h>
+#include <s6-dns/s6dns-ip46.h>
+
+
+ /* The dt structure: all the DNS q/r state information, transport-agnostic */
+
+typedef struct s6dns_engine_s s6dns_engine_t, *s6dns_engine_t_ref ;
+
+
+ /* Debug function hooks */
+
+typedef int s6dns_debughook_func_t (s6dns_engine_t const *, void *) ;
+typedef s6dns_debughook_func_t *s6dns_debughook_func_t_ref ;
+
+typedef struct s6dns_debughook_s s6dns_debughook_t, *s6dns_debughook_t_ref ;
+struct s6dns_debughook_s
+{
+  s6dns_debughook_func_t_ref post_recv ;
+  s6dns_debughook_func_t_ref pre_send ;
+  s6dns_debughook_func_t_ref post_send ;
+  void *external ;
+} ;
+#define S6DNS_DEBUGHOOK_ZERO { 0, 0, 0, 0 }
+extern s6dns_debughook_t const s6dns_debughook_zero ;
+      
+
+ /*
+   s6dns-engine: the asynchronous DNS resolution primitives.
+ */
+
+struct s6dns_engine_s
+{
+  stralloc sa ; /* 2 bytes (qlen) + qlen bytes (query) + answers */
+  tain_t deadline ;
+  tain_t localdeadline ;
+  unsigned int querylen ;
+  int fd ;
+  uint32 protostate ;
+  s6dns_ip46list_t servers ;
+  s6dns_debughook_t const *debughook ;
+  unsigned int curserver ;
+  int status ;
+  unsigned int flagstrict : 1 ;
+  unsigned int flagtcp : 1 ;
+  unsigned int flagconnecting : 1 ;
+  unsigned int flagreading : 1 ;
+  unsigned int flagwriting : 1 ;
+} ;
+
+#define S6DNS_ENGINE_ZERO { \
+  .sa = STRALLOC_ZERO, \
+  .deadline = TAIN_ZERO, \
+  .localdeadline = TAIN_ZERO, \
+  .querylen = 0, \
+  .fd = -1, \
+  .protostate = 0, \
+  .servers = S6DNS_IP46LIST_ZERO, \
+  .debughook = 0, \
+  .curserver = 0, \
+  .status = ECONNABORTED, \
+  .flagstrict = 0, \
+  .flagtcp = 0, \
+  .flagconnecting = 0, \
+  .flagreading = 0, \
+  .flagwriting = 0 \
+}
+
+extern s6dns_engine_t const s6dns_engine_zero ;
+extern s6dns_engine_t s6dns_engine_here ;
+
+extern void s6dns_engine_recycle (s6dns_engine_t *) ;
+extern void s6dns_engine_free (s6dns_engine_t *) ;
+extern void s6dns_engine_freen (s6dns_engine_t *, unsigned int) ;
+
+#define s6dns_engine_init(dt, servers, options, q, qlen, qtype, deadline, stamp) s6dns_engine_init_r(dt, servers, options, q, qlen, qtype, &s6dns_debughook_zero, deadline, stamp)
+#define s6dns_engine_init_g(dt, servers, options, q, qlen, qtype, deadline) s6dns_engine_init(dt, servers, options, q, qlen, qtype, (deadline), &STAMP)
+extern int s6dns_engine_init_r (s6dns_engine_t *, s6dns_ip46list_t const *, uint32, char const *, unsigned int, uint16, s6dns_debughook_t const *, tain_t const *, tain_t const *) ;
+#define s6dns_engine_init_r_g(dt, servers, options, q, qlen, qtype, dbh, deadline) s6dns_engine_init_r(dt, servers, options, q, qlen, qtype, dbh, (deadline), &STAMP)
+
+
+ /* Call before iopause() */
+
+extern void s6dns_engine_nextdeadline (s6dns_engine_t const *, tain_t *) ;
+#define s6dns_engine_isreadable(dt) ((dt)->flagreading)
+#define s6dns_engine_iswritable(dt) ((dt)->flagwriting)
+
+
+ /* Call after iopause(): _timeout if iopause returns 0, _event otherwise */
+
+extern int s6dns_engine_timeout (s6dns_engine_t *, tain_t const *) ;
+#define s6dns_engine_timeout_g(dt) s6dns_engine_timeout((dt), &STAMP)
+extern int s6dns_engine_event (s6dns_engine_t *, tain_t const *) ;
+#define s6dns_engine_event_g(dt) s6dns_engine_event((dt), &STAMP)
+
+#define s6dns_engine_packet(dt) ((dt)->sa.s + (dt)->querylen)
+#define s6dns_engine_packetlen(dt) ((dt)->sa.len - (dt)->querylen)
+
+#endif
diff --git a/src/include/s6-dns/s6dns-fmt.h b/src/include/s6-dns/s6dns-fmt.h
new file mode 100644
index 0000000..fd4dfc5
--- /dev/null
+++ b/src/include/s6-dns/s6dns-fmt.h
@@ -0,0 +1,29 @@
+/* ISC license. */
+
+#ifndef S6DNS_FMT_H
+#define S6DNS_FMT_H
+
+#include <skalibs/uint16.h>
+#include <skalibs/uint32.h>
+#include <s6-dns/s6dns-domain.h>
+#include <s6-dns/s6dns-message.h>
+
+#define S6DNS_FMT_DOMAIN 256
+#define s6dns_fmt_domain(s, max, d) s6dns_domain_tostring(s, max, d)
+
+#define S6DNS_FMT_DOMAINLIST(n) ((n) * S6DNS_FMT_DOMAIN)
+extern unsigned int s6dns_fmt_domainlist (char *, unsigned int, s6dns_domain_t const *, unsigned int, char const *, unsigned int) ;
+
+#define S6DNS_FMT_HINFO 512
+extern unsigned int s6dns_fmt_hinfo (char *, unsigned int, s6dns_message_rr_hinfo_t const *) ;
+
+#define S6DNS_FMT_MX (S6DNS_FMT_DOMAIN + UINT16_FMT)
+extern unsigned int s6dns_fmt_mx (char *, unsigned int, s6dns_message_rr_mx_t const *) ;
+
+#define S6DNS_FMT_SOA (S6DNS_FMT_DOMAIN * 2 + 5 * UINT32_FMT)
+extern unsigned int s6dns_fmt_soa (char *, unsigned int, s6dns_message_rr_soa_t const *) ;
+
+#define S6DNS_FMT_SRV (S6DNS_FMT_DOMAIN + 3 * UINT16_FMT)
+extern unsigned int s6dns_fmt_srv (char *, unsigned int, s6dns_message_rr_srv_t const *) ;
+
+#endif
diff --git a/src/include/s6-dns/s6dns-ip46.h b/src/include/s6-dns/s6dns-ip46.h
new file mode 100644
index 0000000..d09aa7f
--- /dev/null
+++ b/src/include/s6-dns/s6dns-ip46.h
@@ -0,0 +1,29 @@
+/* ISC license. */
+
+#ifndef S6DNS_IP46_H
+#define S6DNS_IP46_H
+
+#include <skalibs/bitarray.h>
+#include <skalibs/ip46.h>
+#include <s6-dns/s6dns-constants.h>
+
+typedef struct s6dns_ip46list_s s6dns_ip46list_t, *s6dns_ip46list_t_ref ;
+struct s6dns_ip46list_s
+{
+  char ip[S6DNS_MAX_SERVERS * SKALIBS_IP_SIZE] ;
+#ifdef SKALIBS_IPV6_ENABLED
+  unsigned char is6[bitarray_div8(S6DNS_MAX_SERVERS)] ;
+#endif
+} ;
+
+#define s6dns_ip46list_ip(list, i) ((list)->ip + SKALIBS_IP_SIZE * (i))
+
+#ifdef SKALIBS_IPV6_ENABLED
+# define S6DNS_IP46LIST_ZERO { .ip = S6DNS_LOCALHOST_IP, .is6 = "\0" }
+# define s6dns_ip46list_is6(list, i) bitarray_peek((list)->is6, i)
+#else
+# define S6DNS_IP46LIST_ZERO { .ip = S6DNS_LOCALHOST_IP }
+# define s6dns_ip46list_is6(list, i) 0
+#endif
+    
+#endif    
diff --git a/src/include/s6-dns/s6dns-message.h b/src/include/s6-dns/s6dns-message.h
new file mode 100644
index 0000000..d26106b
--- /dev/null
+++ b/src/include/s6-dns/s6dns-message.h
@@ -0,0 +1,175 @@
+/* ISC license. */
+
+#ifndef S6DNS_MESSAGE_H
+#define S6DNS_MESSAGE_H
+
+#include <skalibs/uint16.h>
+#include <skalibs/uint32.h>
+#include <skalibs/stralloc.h>
+#include <skalibs/genalloc.h>
+#include <s6-dns/s6dns-domain.h>
+
+
+ /* Header */
+
+typedef struct s6dns_message_counts_s s6dns_message_counts_t, *s6dns_message_counts_t_ref ;
+struct s6dns_message_counts_s
+{
+  uint16 qd ;
+  uint16 an ;
+  uint16 ns ;
+  uint16 nr ;
+} ;
+
+#define S6DNS_MESSAGE_COUNTS_ZERO { .qd = 0, .an = 0, .ns = 0, .nr = 0 }
+extern s6dns_message_counts_t const s6dns_message_counts_zero ;
+
+extern void s6dns_message_counts_pack (char *, s6dns_message_counts_t const *) ;
+extern void s6dns_message_counts_unpack (char const *, s6dns_message_counts_t *) ;
+extern unsigned int s6dns_message_counts_next (s6dns_message_counts_t *) ;
+
+typedef struct s6dns_message_header_s s6dns_message_header_t, *s6dns_message_header_t_ref ;
+struct s6dns_message_header_s
+{
+  uint16 id ;
+  unsigned int qr : 1 ;
+  unsigned int opcode : 4 ;
+  unsigned int aa : 1 ;
+  unsigned int tc : 1 ;
+  unsigned int rd : 1 ;
+  unsigned int ra : 1 ;
+  unsigned int z : 3 ;
+  unsigned int rcode : 4 ;
+  s6dns_message_counts_t counts ;
+} ;
+
+#define S6DNS_MESSAGE_HEADER_ZERO { \
+  .id = 0, \
+  .qr = 0, \
+  .opcode = 0, \
+  .aa = 0, \
+  .tc = 0, \
+  .rd = 0, \
+  .ra = 0, \
+  .z = 0, \
+  .rcode = 0, \
+  .counts = S6DNS_MESSAGE_COUNTS_ZERO \
+}
+extern s6dns_message_header_t const s6dns_message_header_zero ;
+
+extern void s6dns_message_header_pack (char *, s6dns_message_header_t const *) ;
+extern void s6dns_message_header_unpack (char const *, s6dns_message_header_t *) ;
+
+
+ /* Specific RR helpers */
+
+extern int s6dns_message_get_string (s6dns_domain_t *, char const *, unsigned int, unsigned int *) ;
+extern int s6dns_message_get_strings (char *, unsigned int, char const *, unsigned int, unsigned int *) ;
+extern int s6dns_message_get_domain (s6dns_domain_t *, char const *, unsigned int, unsigned int *) ;
+
+typedef struct s6dns_message_rr_hinfo_s s6dns_message_rr_hinfo_t, *s6dns_message_rr_hinfo_t_ref ;
+struct s6dns_message_rr_hinfo_s
+{
+  s6dns_domain_t cpu ;
+  s6dns_domain_t os ;
+} ;
+
+extern int s6dns_message_get_hinfo (s6dns_message_rr_hinfo_t *, char const *, unsigned int, unsigned int *) ;
+
+typedef struct s6dns_message_rr_mx_s s6dns_message_rr_mx_t, *s6dns_message_rr_mx_t_ref ;
+struct s6dns_message_rr_mx_s
+{
+  uint16 preference ;
+  s6dns_domain_t exchange ;
+} ;
+
+extern int s6dns_message_get_mx (s6dns_message_rr_mx_t *, char const *, unsigned int, unsigned int *) ;
+
+typedef struct s6dns_message_rr_soa_s s6dns_message_rr_soa_t, *s6dns_message_rr_soa_t_ref ;
+struct s6dns_message_rr_soa_s
+{
+  s6dns_domain_t mname ;
+  s6dns_domain_t rname ;
+  uint32 serial ;
+  uint32 refresh ;
+  uint32 retry ;
+  uint32 expire ;
+  uint32 minimum ;
+} ;
+
+extern int s6dns_message_get_soa (s6dns_message_rr_soa_t *, char const *, unsigned int, unsigned int *) ;
+
+typedef struct s6dns_message_rr_srv_s s6dns_message_rr_srv_t, *s6dns_message_rr_srv_t_ref ;
+struct s6dns_message_rr_srv_s
+{
+  uint16 priority ;
+  uint16 weight ;
+  uint16 port ;
+  s6dns_domain_t target ;
+} ;
+
+extern int s6dns_message_get_srv (s6dns_message_rr_srv_t *, char const *, unsigned int, unsigned int *) ;
+
+
+ /* The callback function type: how to parse RRs */
+
+typedef struct s6dns_message_rr_s s6dns_message_rr_t, *s6dns_message_rr_t_ref ;
+struct s6dns_message_rr_s
+{
+  s6dns_domain_t name ;
+  uint16 rtype ;
+  uint16 rclass ;
+  uint32 ttl ;
+  uint16 rdlength ;
+} ;
+
+typedef int s6dns_message_rr_func_t (s6dns_message_rr_t const *, char const *, unsigned int, unsigned int, unsigned int, void *) ;
+typedef s6dns_message_rr_func_t *s6dns_message_rr_func_t_ref ;
+
+
+ /* mpag: structure to encode several variable-length results */
+
+typedef struct s6dns_mpag_s s6dns_mpag_t, *s6dns_mpag_t_ref ;
+struct s6dns_mpag_s
+{
+  stralloc sa ;
+  genalloc offsets ; /* array of unsigned int */
+  uint16 rtype ;
+} ;
+#define S6DNS_MPAG_ZERO { .sa = STRALLOC_ZERO, .offsets = GENALLOC_ZERO, .rtype = 0 }
+
+
+ /* dpag: structure for domain lists */
+
+typedef struct s6dns_dpag_s s6dns_dpag_t, *s6dns_dpag_t_ref ;
+struct s6dns_dpag_s
+{
+  genalloc ds ; /* array of s6dns_domain_t */
+  uint16 rtype ;
+} ;
+#define S6DNS_DPAG_ZERO { .ds = GENALLOC_ZERO, .rtype = 0 }
+
+
+extern s6dns_message_rr_func_t s6dns_message_parse_answer_strings ;
+extern s6dns_message_rr_func_t s6dns_message_parse_answer_domain ;
+extern s6dns_message_rr_func_t s6dns_message_parse_answer_a ;
+extern s6dns_message_rr_func_t s6dns_message_parse_answer_aaaa ;
+extern s6dns_message_rr_func_t s6dns_message_parse_answer_mx ;
+extern s6dns_message_rr_func_t s6dns_message_parse_answer_hinfo ;
+extern s6dns_message_rr_func_t s6dns_message_parse_answer_soa ;
+extern s6dns_message_rr_func_t s6dns_message_parse_answer_srv ;
+
+
+ /* The actual parsing function */
+
+extern int s6dns_message_parse (s6dns_message_header_t_ref, char const *, unsigned int, s6dns_message_rr_func_t_ref, void *) ;
+
+
+ /* Internals of this function, for lower level access */
+
+extern int s6dns_message_parse_init (s6dns_message_header_t *, s6dns_message_counts_t_ref, char const *, unsigned int, unsigned int *) ;
+extern unsigned int s6dns_message_parse_skipqd (s6dns_message_counts_t *, char const *, unsigned int, unsigned int *) ;
+extern int s6dns_message_parse_getrr (s6dns_message_rr_t_ref, char const *, unsigned int, unsigned int *) ;
+extern unsigned int s6dns_message_parse_next (s6dns_message_counts_t *, s6dns_message_rr_t const *, char const *, unsigned int, unsigned int *) ;
+
+#endif
diff --git a/src/include/s6-dns/s6dns-rci.h b/src/include/s6-dns/s6dns-rci.h
new file mode 100644
index 0000000..5822a71
--- /dev/null
+++ b/src/include/s6-dns/s6dns-rci.h
@@ -0,0 +1,29 @@
+/* ISC license. */
+
+#ifndef S6DNS_RCI_H
+#define S6DNS_RCI_H
+
+#include <skalibs/stralloc.h>
+#include <skalibs/s6dns-constants.h>
+#include <skalibs/s6dns-ip46.h>
+#include <skalibs/s6dns-domain.h>
+
+ /* rci: resolv.conf information */
+
+typedef struct s6dns_rci_s s6dns_rci_t, *s6dns_rci_t_ref ;
+struct s6dns_rci_s
+{
+  s6dns_ip46list_t servers ;
+  stralloc rules ;
+  unsigned int rulesnum ;
+} ;
+#define S6DNS_RCI_ZERO { .servers = S6DNS_IP46LIST_ZERO, .rules = STRALLOC_ZERO, .rulesnum = 0 }
+
+extern s6dns_rci_t const s6dns_rci_zero ;
+extern s6dns_rci_t s6dns_rci_here ;
+extern int s6dns_rci_init (s6dns_rci_t_ref, char const *) ;
+extern void s6dns_rci_free (s6dns_rci_t_ref) ;
+
+#define s6dns_qualify(list, d) s6dns_domain_qualify(list, (d), s6dns_rci_here.rules.s, s6dns_rci_here.rulesnum)
+
+#endif
diff --git a/src/include/s6-dns/s6dns-resolve.h b/src/include/s6-dns/s6dns-resolve.h
new file mode 100644
index 0000000..d188a67
--- /dev/null
+++ b/src/include/s6-dns/s6dns-resolve.h
@@ -0,0 +1,242 @@
+ /* ISC license. */
+
+#ifndef S6DNS_RESOLVE_H
+#define S6DNS_RESOLVE_H
+
+#include <errno.h>
+#include <skalibs/uint16.h>
+#include <skalibs/uint32.h>
+#include <skalibs/tai.h>
+#include <skalibs/stralloc.h>
+#include <skalibs/genalloc.h>
+#include <skalibs/ip46.h>
+#include <skalibs/s6dns-constants.h>
+#include <skalibs/s6dns-ip46.h>
+#include <skalibs/s6dns-domain.h>
+#include <skalibs/s6dns-message.h>
+#include <skalibs/s6dns-engine.h>
+#include <skalibs/s6dns-rci.h>
+
+ /*
+    Synchronous DNS resolution primitives.
+    The non-reentrant functions are just wrappers around the reentrant ones,
+    using globals for the parameters the user doesn't care about:
+    s6dns_engine_here for the query storage (dt),
+    s6dns_debughook_zero meaning no debugging needed,
+    s6dns_rci_here for the resolv.conf information (qualification rules and
+    initial cache IPs)
+ */
+
+ /*
+    The basic s6dns_engine wrapper loop: takes an initted dt and resolves it.
+ */
+
+#define s6dns_resolve_loop(deadline, stamp) s6dns_resolve_loop_r(&s6dns_engine_here, (deadline), stamp)
+#define s6dns_resolve_loop_g(deadline) s6dns_resolve_loop((deadline), &STAMP)
+#define s6dns_resolve_loop_r(dt, deadline, stamp) (s6dns_resolven_loop(dt, 1, 2, deadline, stamp) < 0 ? 0 : (dt)->status ? (errno = (dt)->status, 0) : 1)
+#define s6dns_resolve_loop_r_g(dt, deadline) s6dns_resolve_loop(dt, (deadline), &STAMP)
+
+
+ /*  QoL functions for single-domain synchronous resolution. */
+
+ /*
+    The innermost one:
+    Initializes the dt with the given data (d, qtype), then calls the loop.
+ */
+
+#define s6dns_resolve_core(d, qtype, deadline, stamp) s6dns_resolve_core_r(d, qtype, &s6dns_engine_here, &s6dns_rci_here.servers, &s6dns_debughook_zero, deadline, stamp)
+#define s6dns_resolve_core_g(d, qtype, deadline) s6dns_resolve_core(d, qtype, (deadline), &STAMP)
+extern int s6dns_resolve_core_r (s6dns_domain_t const *, uint16, s6dns_engine_t_ref, s6dns_ip46list_t const *, s6dns_debughook_t const *, tain_t const *, tain_t *) ;
+#define s6dns_resolve_core_r_g(d, qtype, dt, servers, dbh, deadline) s6dns_resolve_core_r(d, qtype, dt, servers, dbh, (deadline), &STAMP)
+
+
+ /*
+    Just above. Calls s6dns_resolve_core() then feeds the result to s6dns_message_parse().
+    Returns -1 if a resolving or parsing error occurs.
+    Returns 0 if everything works but the result is empty for some reason (i.e. nxdomain).
+    Returns 1 if everything works and there's an actual answer.
+ */
+
+#define s6dns_resolve_parse(d, qtype, parsefunc, parsedata, deadline, stamp) s6dns_resolve_parse_r(d, qtype, parsefunc, parsedata, &s6dns_engine_here, &s6dns_rci_here.servers, &s6dns_debughook_zero, deadline, stamp)
+#define s6dns_resolve_parse_g(d, qtype, parsefunc, parsedata, deadline) s6dns_resolve_parse(d, qtype, parsefunc, parsedata, (deadline), &STAMP)
+extern int s6dns_resolve_parse_r (s6dns_domain_t const *, uint16, s6dns_message_rr_func_t_ref, void *, s6dns_engine_t_ref, s6dns_ip46list_t const *, s6dns_debughook_t const *, tain_t const *, tain_t *) ;
+#define s6dns_resolve_parse_r_g(d, qtype, parsefunc, parsedata, dt, servers, dbh, deadline) s6dns_resolve_parse_r(d, qtype, parsefunc, parsedata, dt, servers, dbh, (deadline), &STAMP)
+
+
+ /*
+    Resolution without qualification. Encoding/decoding included.
+ */
+
+#define s6dns_resolvenoq(name, len, qtype, parsefunc, parsedata, deadline, stamp) s6dns_resolvenoq_r(name, len, qtype, parsefunc, parsedata, &s6dns_engine_here, &s6dns_rci_here.servers, &s6dns_debughook_zero, deadline, stamp)
+#define s6dns_resolvenoq_g(name, len, qtype, parsefunc, parsedata, deadline) s6dns_resolvenoq(name, len, qtype, parsefunc, parsedata, (deadline), &STAMP)
+extern int s6dns_resolvenoq_r (char const *, unsigned int, uint16, s6dns_message_rr_func_t_ref, void *, s6dns_engine_t_ref, s6dns_ip46list_t const *, s6dns_debughook_t const *, tain_t const *, tain_t *) ;
+#define s6dns_resolvenoq_r_g(name, len, qtype, parsefunc, parsedata, dt, servers, dbh, deadline) s6dns_resolvenoq_r(name, len, qtype, parsefunc, parsedata, dt, servers, dbh, (deadline), &STAMP)
+
+
+ /*
+    Resolution with qualification:
+    Get a qualification list from a name, then resolve the list in parallel.
+ */
+
+#define s6dns_resolveq(name, len, qtype, parsefunc, parsedata, deadline, stamp) s6dns_resolveq_r(name, len, qtype, parsefunc, parsedata, &s6dns_rci_here, &s6dns_debughook_zero, deadline, stamp)
+#define s6dns_resolveq_g(name, len, qtype, parsefunc, parsedata, deadline) s6dns_resolveq(name, len, qtype, parsefunc, parsedata, (deadline), &STAMP)
+extern int s6dns_resolveq_r (char const *, unsigned int, uint16, s6dns_message_rr_func_t_ref, void *, s6dns_rci_t const *, s6dns_debughook_t const *, tain_t const *, tain_t *) ;
+#define s6dns_resolveq_r_g(name, len, qtype, parsefunc, parsedata, rci, dbh, deadline) s6dns_resolveq_r(name, len, qtype, parsefunc, parsedata, rci, dbh, (deadline), &STAMP)
+
+
+ /*
+    The resolution primitive that calls s6dns_resolvenoq() if the
+    qualif flag is cleared and s6dns_resolveq() if it is set.
+ */
+
+#define s6dns_resolve(name, len, qtype, parsefunc, parsedata, qualif, deadline, stamp) s6dns_resolve_r(name, len, qtype, parsefunc, parsedata, qualif, &s6dns_engine_here, &s6dns_rci_here, &s6dns_debughook_t const *, deadline, stamp)
+#define s6dns_resolve_g(name, len, qtype, parsefunc, parsedata, qualif, deadline) s6dns_resolve(name, len, qtype, parsefunc, parsedata, qualif, (deadline), &STAMP)
+#define s6dns_resolve_r(name, len, qtype, parsefunc, parsedata, qualif, dt, rci, dbh, deadline, stamp) ((qualif) ? s6dns_resolveq_r(name, len, qtype, parsefunc, parsedata, rci, dbh, deadline, stamp) : s6dns_resolvenoq_r(name, len, qtype, parsefunc, parsedata, dt, &(rci)->servers, dbh, deadline, stamp))
+#define s6dns_resolve_r_g(name, len, qtype, parsefunc, parsedata, qualif, dt, rci, dbh, deadline) s6dns_resolve_r(name, len, qtype, parsefunc, parsedata, qualif, dt, rci, dbh, (deadline), &STAMP)
+
+
+ /* How to perform both AAAA and A queries at the same time */
+
+#define s6dns_resolvenoq_aaaaa(ips, name, len, deadline, stamp) s6dns_resolvenoq_aaaaa_r(ips, name, len, &s6dns_rci_here.servers, &s6dns_debughook_zero, deadline, stamp)
+#define s6dns_resolvenoq_aaaaa_g(ips, name, len, deadline) s6dns_resolvenoq_aaaaa(ips, name, len, (deadline), &STAMP)
+extern int s6dns_resolvenoq_aaaaa_r(genalloc *, char const *, unsigned int, s6dns_ip46list_t const *, s6dns_debughook_t const *, tain_t const *, tain_t *) ;
+#define s6dns_resolvenoq_aaaaa_r_g(ips, name, len, servers, dbh, deadline) s6dns_resolvenoq_aaaaa_r(ips, name, len, servers, dbh, (deadline), &STAMP)
+
+#define s6dns_resolveq_aaaaa(ips, name, len, deadline, stamp) s6dns_resolveq_aaaaa_r(ips, name, len, &s6dns_rci_here, &s6dns_debughook_zero, deadline, stamp)
+#define s6dns_resolveq_aaaaa_g(ips, name, len, deadline) s6dns_resolveq_aaaaa(ips, name, len, (deadline), &STAMP)
+extern int s6dns_resolveq_aaaaa_r(genalloc *, char const *, unsigned int, s6dns_rci_t const *, s6dns_debughook_t const *, tain_t const *, tain_t *) ;
+#define s6dns_resolveq_aaaaa_r_g(ips, name, len, rci, dbh, deadline) s6dns_resolvenoq_aaaaa_r(ips, name, len, rci, dbh, (deadline), &STAMP)
+
+
+ /*
+    Some high-level functions.
+    Queries are automatically translated to domain form and encoded.
+    Domains returned in a stralloc are automatically decoded.
+    Warning: decoded domains all start with '.'
+    The int flag decides if qualification is needed or not.
+ */
+
+ /*
+   For A fields: the stralloc answer has 4 chars per IP4.
+   For AAAA fields: the stralloc answer has 16 chars per IP6.
+   For TXT fields (and other mpag stuff): the stralloc contains the strings
+     and the genalloc contains a list of offsets into that stralloc.
+   For other fields: the result is stored in a genalloc of the appropriate type.
+ */
+
+#define s6dns_resolve_a(ips, name, len, qualif, deadline, stamp) s6dns_resolve_a_r(ips, name, len, qualif, &s6dns_engine_here, &s6dns_rci_here, &s6dns_debughook_zero, deadline, stamp)
+#define s6dns_resolve_a_g(ips, name, len, qualif, deadline) s6dns_resolve_a(ips, name, len, qualif, (deadline), &STAMP)
+#define s6dns_resolve_a_r(ips, name, len, qualif, dt, rci, dbh, deadline, stamp) s6dns_resolve_r(name, len, S6DNS_T_A, &s6dns_message_parse_answer_a, (ips), qualif, dt, rci, dbh, deadline, stamp)
+#define s6dns_resolve_a_r_g(ips, name, len, qualif, dt, rci, dbh, deadline) s6dns_resolve_a_r(ips, name, len, qualif, dt, rci, dbh, (deadline), &STAMP)
+
+#define s6dns_resolve_aaaa(ip6s, name, len, qualif, deadline, stamp) s6dns_resolve_aaaa_r(ip6s, name, len, qualif, &s6dns_engine_here, &s6dns_rci_here, &s6dns_debughook_zero, deadline, stamp)
+#define s6dns_resolve_aaaa_g(ip6s, name, len, qualif, deadline) s6dns_resolve_aaaa(ip6s, name, len, qualif, (deadline), &STAMP)
+#define s6dns_resolve_aaaa_r(ip6s, name, len, qualif, dt, rci, dbh, deadline, stamp) s6dns_resolve_r(name, len, S6DNS_T_AAAA, &s6dns_message_parse_answer_aaaa, (ip6s), qualif, dt, rci, dbh, deadline, stamp)
+#define s6dns_resolve_aaaa_r_g(ip6s, name, len, qualif, dt, rci, dbh, deadline) s6dns_resolve_aaaa_r(ip6s, name, len, qualif, dt, rci, dbh, (deadline), &STAMP)
+
+#define s6dns_resolve_aaaaa(ips, name, len, qualif, deadline, stamp) s6dns_resolve_aaaaa_r(ips, name, len, qualif, &s6dns_rci_here, &s6dns_debughook_zero, deadline, stamp)
+#define s6dns_resolve_aaaaa_g(ips, name, len, qualif, deadline) s6dns_resolve_aaaaa(ips, name, len, qualif, (deadline), &STAMP)
+#define s6dns_resolve_aaaaa_r(ips, name, len, qualif, rci, dbh, deadline, stamp) ((qualif) ? s6dns_resolveq_aaaaa_r(ips, name, len, rci, dbh, deadline, stamp) : s6dns_resolvenoq_aaaaa_r(ips, name, len, &(rci)->servers, dbh, deadline, stamp))
+#define s6dns_resolve_aaaaa_r_g(ips, name, len, qualif, rci, dbh, deadline) s6dns_resolve_aaaaa_r(ips, name, len, qualif, rci, dbh, (deadline), &STAMP)
+
+#define s6dns_resolve_ptr(ds, name, len, deadline, stamp) s6dns_resolve_ptr_r(ds, name, len, &s6dns_engine_here, &s6dns_rci_here.servers, &s6dns_debughook_zero, deadline, stamp)
+#define s6dns_resolve_ptr_g(ds, name, len, deadline) s6dns_resolve_ptr(ds, name, len, (deadline), &STAMP)
+#define s6dns_resolve_ptr_r(ds, name, len, dt, servers, dbh, deadline, stamp) s6dns_resolvenoq_r(name, len, S6DNS_T_PTR, &s6dns_message_parse_answer_domain, (ds), dt, servers, dbh, deadline, stamp)
+#define s6dns_resolve_ptr_r_g(ds, name, len, dt, servers, dbh, deadline) s6dns_resolve_ptr_r(ds, name, len, dt, servers, dbh, (deadline), &STAMP)
+
+#define s6dns_resolve_name4(ds, ip, deadline, stamp) s6dns_resolve_name4_r(ds, ip, &s6dns_engine_here, &s6dns_rci_here.servers, &s6dns_debughook_zero, deadline, stamp)
+#define s6dns_resolve_name4_g(ds, ip, deadline) s6dns_resolve_name4(ds, ip, (deadline), &STAMP)
+extern int s6dns_resolve_name4_r (genalloc *, char const *, s6dns_engine_t_ref, s6dns_ip46list_t const *, s6dns_debughook_t const *, tain_t const *, tain_t *) ;
+#define s6dns_resolve_name4_r_g(ds, ip, dt, servers, dbh, deadline) s6dns_resolve_name4_r(ds, ip, dt, servers, dbh, (deadline), &STAMP)
+
+#define s6dns_resolve_name6(ds, ip6, deadline, stamp) s6dns_resolve_name6_r(ds, ip6, &s6dns_engine_here, &s6dns_rci_here.servers, &s6dns_debughook_zero, deadline, stamp)
+#define s6dns_resolve_name6_g(ds, ip6, deadline) s6dns_resolve_name6(ds, ip6, (deadline), &STAMP)
+extern int s6dns_resolve_name6_r (genalloc *, char const *, s6dns_engine_t_ref, s6dns_ip46list_t const *, s6dns_debughook_t const *, tain_t const *, tain_t *) ;
+#define s6dns_resolve_name6_r_g(ds, ip6, dt, servers, dbh, deadline) s6dns_resolve_name6_r(ds, ip6, dt, servers, dbh, (deadline), &STAMP)
+
+#define s6dns_resolve_name46(ds, i, deadline, stamp) s6dns_resolve_name46_r(ds, i, &s6dns_engine_here, &s6dns_rci_here.servers, &s6dns_debughook_zero, deadline, stamp)
+#define s6dns_resolve_name46_g(ds, i, deadline) s6dns_resolve_name46(ds, i, (deadline), &STAMP)
+#define s6dns_resolve_name46_r(ds, i, dt, servers, dbh, deadline, stamp) (ip46_is6(i) ? s6dns_resolve_name6_r(ds, (i)->ip, dt, servers, dbh, deadline, stamp) : s6dns_resolve_name4_r(ds, (i)->ip, dt, servers, dbh, deadline, stamp))
+#define s6dns_resolve_name46_r_g(ds, i, dt, servers, dbh, deadline) s6dns_resolve_name46_r(ds, i, dt, servers, dbh, (deadline), &STAMP)
+
+#define s6dns_resolve_txt(sa, offsets, name, len, qualif, deadline, stamp) s6dns_resolve_txt_r(sa, offsets, name, len, qualif, &s6dns_engine_here, &s6dns_rci_here, &s6dns_debughook_zero, deadline, stamp)
+#define s6dns_resolve_txt_g(sa, offsets, name, len, qualif, deadline) s6dns_resolve_txt(sa, offsets, name, len, qualif, (deadline), &STAMP)
+#define s6dns_resolve_txt_r(sa, offsets, name, len, qualif, dt, rci, dbh, deadline, stamp) s6dns_resolve_mpag_r(sa, offsets, name, len, S6DNS_T_TXT, &s6dns_message_parse_answer_strings, qualif, dt, rci, dbh, deadline, stamp)
+#define s6dns_resolve_txt_r_g(sa, offsets, name, len, qualif, dt, rci, dbh, deadline) s6dns_resolve_txt_r(sa, offsets, name, len, qualif, dt, rci, dbh, (deadline), &STAMP)
+
+#define s6dns_resolve_mx(mxs, name, len, qualif, deadline, stamp) s6dns_resolve_mx_r(mxs, name, len, qualif, &s6dns_engine_here, &s6dns_rci_here, &s6dns_debughook_zero, deadline, stamp)
+#define s6dns_resolve_mx_g(mxs, name, len, qualif, deadline) s6dns_resolve_mx(mxs, name, len, qualif, (deadline), &STAMP)
+#define s6dns_resolve_mx_r(mxs, name, len, qualif, dt, rci, dbh, deadline, stamp) s6dns_resolve_r(name, len, S6DNS_T_MX, &s6dns_message_parse_answer_mx, (mxs), qualif, dt, rci, dbh, deadline, stamp)
+#define s6dns_resolve_mx_r_g(mxs, name, len, qualif, dt, rci, dbh, deadline) s6dns_resolve_mx_r(mxs, name, len, qualif, dt, rci, dbh, (deadline), &STAMP)
+
+#define s6dns_resolve_ns(ds, name, len, qualif, deadline, stamp) s6dns_resolve_ns_r(ds, name, len, qualif, &s6dns_engine_here, &s6dns_rci_here, &s6dns_debughook_zero, deadline, stamp)
+#define s6dns_resolve_ns_g(ds, name, len, qualif, deadline) s6dns_resolve_ns(ds, name, len, qualif, (deadline), &STAMP)
+#define s6dns_resolve_ns_r(ds, name, len, qualif, dt, rci, dbh, deadline, stamp) s6dns_resolve_dpag_r(ds, name, len, S6DNS_T_NS, qualif, dt, rci, dbh, deadline, stamp)
+#define s6dns_resolve_ns_r_g(ds, name, len, qualif, dt, rci, dbh, deadline) s6dns_resolve_ns_r(ds, name, len, qualif, dt, rci, dbh, (deadline), &STAMP)
+
+#define s6dns_resolve_cname(ds, name, len, qualif, deadline, stamp) s6dns_resolve_cname_r(ds, name, len, qualif, &s6dns_engine_here, &s6dns_rci_here, &s6dns_debughook_zero, deadline, stamp)
+#define s6dns_resolve_cname_g(ds, name, len, qualif, deadline) s6dns_resolve_cname(ds, name, len, qualif, (deadline), &STAMP)
+#define s6dns_resolve_cname_r(ds, name, len, qualif, dt, rci, dbh, deadline, stamp) s6dns_resolve_dpag_r(ds, name, len, S6DNS_T_CNAME, qualif, dt, rci, dbh, deadline, stamp)
+#define s6dns_resolve_cname_r_g(ds, name, len, qualif, dt, rci, dbh, deadline) s6dns_resolve_cname_r(ds, name, len, qualif, dt, rci, dbh, (deadline), &STAMP)
+
+#define s6dns_resolve_hinfo(hinfos, name, len, qualif, deadline, stamp) s6dns_resolve_hinfo_r(hinfos, name, len, qualif, &s6dns_engine_here, &s6dns_rci_here, &s6dns_debughook_zero, deadline, stamp)
+#define s6dns_resolve_hinfo_g(hinfos, name, len, qualif, deadline) s6dns_resolve_hinfo(hinfos, name, len, qualif, (deadline), &STAMP)
+#define s6dns_resolve_hinfo_r(hinfos, name, len, qualif, dt, rci, dbh, deadline, stamp) s6dns_resolve_r(name, len, S6DNS_T_HINFO, &s6dns_message_parse_answer_hinfo, (hinfos), qualif, dt, rci, dbh, deadline, stamp)
+#define s6dns_resolve_hinfo_r_g(hinfos, name, len, qualif, dt, rci, dbh, deadline) s6dns_resolve_hinfo_r(hinfos, name, len, qualif, dt, rci, dbh, (deadline), &STAMP)
+
+#define s6dns_resolve_srv(srvs, name, len, qualif, deadline, stamp) s6dns_resolve_srv_r(srvs, name, len, qualif, &s6dns_engine_here, &s6dns_rci_here, &s6dns_debughook_zero, deadline, stamp)
+#define s6dns_resolve_srv_g(srvs, name, len, qualif, deadline) s6dns_resolve_srv(srvs, name, len, qualif, (deadline), &STAMP)
+#define s6dns_resolve_srv_r(srvs, name, len, qualif, dt, rci, dbh, deadline, stamp) s6dns_resolve_r(name, len, S6DNS_T_SRV, &s6dns_message_parse_answer_srv, (srvs), qualif, dt, rci, dbh, deadline, stamp)
+#define s6dns_resolve_srv_r_g(srvs, name, len, qualif, dt, rci, dbh, deadline) s6dns_resolve_srv_r(srvs, name, len, qualif, dt, rci, dbh, (deadline), &STAMP)
+
+#define s6dns_resolve_soa(soas, name, len, qualif, deadline, stamp) s6dns_resolve_soa_r(soas, name, len, qualif, &s6dns_engine_here, &s6dns_rci_here, &s6dns_debughook_zero, deadline, stamp)
+#define s6dns_resolve_soa_g(soas, name, len, qualif, deadline) s6dns_resolve_soa(soas, name, len, qualif, (deadline), &STAMP)
+#define s6dns_resolve_soa_r(soas, name, len, qualif, dt, rci, dbh, deadline, stamp) s6dns_resolve_r(name, len, S6DNS_T_SOA, &s6dns_message_parse_answer_soa, (soas), qualif, dt, rci, dbh, deadline, stamp)
+#define s6dns_resolve_soa_r_g(soas, name, len, qualif, dt, rci, dbh, deadline) s6dns_resolve_soa_r(soas, name, len, qualif, dt, rci, dbh, (deadline), &STAMP)
+
+
+ /* Internals for the high-level functions. */
+
+  /* dpag: structure for generic domain lists + rtype */
+  /* mpag: encoding variable-length information into storage+offsets */
+
+#define s6dns_resolve_dpag(ds, name, len, qtype, qualif, deadline, stamp) s6dns_resolve_dpag_r(ds, name, len, qtype, qualif, &s6dns_engine_here, &s6dns_rci_here, &s6dns_debughook_zero, deadline, stamp)
+#define s6dns_resolve_dpag_g(ds, name, len, qtype, qualif, deadline) s6dns_resolve_dpag(ds, name, len, qtype, qualif, (deadline), &STAMP)
+extern int s6dns_resolve_dpag_r (genalloc *, char const *, unsigned int, uint16, int, s6dns_engine_t_ref, s6dns_rci_t const *, s6dns_debughook_t const *, tain_t const *, tain_t *) ;
+#define s6dns_resolve_dpag_r_g(ds, name, len, qtype, qualif, dt, rci, dbh, deadline) s6dns_resolve_dpag_r(ds, name, len, qtype, qualif, dt, rci, dbh, (deadline), &STAMP)
+
+#define s6dns_resolve_mpag(sa, offsets, name, len, qtype, parsefunc, qualif, deadline, stamp) s6dns_resolve_mpag_r(sa, offsets, name, len, qtype, parsefunc, qualif, &s6dns_engine_here, &s6dns_rci_here, &s6dns_debughook_zero, deadline, stamp)
+#define s6dns_resolve_mpag_g(sa, offsets, name, len, qtype, parsefunc, qualif, deadline) s6dns_resolve_mpag(sa, offsets, name, len, qtype, parsefunc, qualif, (deadline), &STAMP)
+extern int s6dns_resolve_mpag_r (stralloc *, genalloc *, char const *, unsigned int, uint16, s6dns_message_rr_func_t_ref, int, s6dns_engine_t_ref, s6dns_rci_t const *, s6dns_debughook_t const *, tain_t const *, tain_t *) ;
+#define s6dns_resolve_mpag_r_g(sa, offsets, name, len, qtype, parsefunc, qualif, dt, rci, dbh, deadline) s6dns_resolve_mpag_r(sa, offsets, name, len, qtype, parsefunc, qualif, dt, rci, dbh, (deadline), &STAMP)
+
+
+ /*
+    Functions for n-domain parallel resolution.
+    s6dns_resolven_loop() is the core primitive.
+    s6dns_resolven_parse() is built upon it.
+    This API is still very limited in what it can do; for full
+    asynchronous resolution, use the skadns library.
+ */
+
+extern int s6dns_resolven_loop (s6dns_engine_t_ref, unsigned int, unsigned int, tain_t const *, tain_t *) ;
+#define s6dns_resolven_loop_g(list, n, or, deadline) s6dns_resolven(list, n, or, (deadline), &STAMP)
+
+typedef struct s6dns_resolve_s s6dns_resolve_t, *s6dns_resolve_t_ref ;
+struct s6dns_resolve_s
+{
+  s6dns_domain_t q ;
+  tain_t deadline ;
+  s6dns_message_rr_func_t_ref parsefunc ;
+  void *data ;
+  uint32 options ;
+  int status ;
+  uint16 qtype ;
+} ;
+
+#define s6dns_resolven_parse(list, n, deadline, stamp) s6dns_resolven_parse_r(list, n, &s6dns_rci_here.servers, &s6dns_debughook_zero, deadline, stamp)
+#define s6dns_resolven_parse_g(list, n, deadline) s6dns_resolven_parse(list, n, (deadline), &STAMP)
+extern int s6dns_resolven_parse_r (s6dns_resolve_t_ref, unsigned int, s6dns_ip46list_t const *, s6dns_debughook_t const *, tain_t const *, tain_t *) ;
+#define s6dns_resolven_parse_r_g(list, n, servers, dbh, deadline) s6dns_resolven_parse_r(list, n, servers, dbh, (deadline), &STAMP)
+
+#endif
diff --git a/src/include/s6-dns/s6dns.h b/src/include/s6-dns/s6dns.h
new file mode 100644
index 0000000..dbc1138
--- /dev/null
+++ b/src/include/s6-dns/s6dns.h
@@ -0,0 +1,18 @@
+/* ISC license. */
+
+#ifndef S6DNS_H
+#define S6DNS_H
+
+#include <s6-dns/s6dns-constants.h>
+#include <s6-dns/s6dns-ip46.h>
+#include <s6-dns/s6dns-domain.h>
+#include <s6-dns/s6dns-message.h>
+#include <s6-dns/s6dns-engine.h>
+#include <s6-dns/s6dns-rci.h>
+#include <s6-dns/s6dns-resolve.h>
+#include <s6-dns/s6dns-fmt.h>
+
+#define s6dns_init() s6dns_rci_init(&s6dns_rci_here, "/etc/resolv.conf")
+#define s6dns_finish() (s6dns_engine_free(&s6dns_engine_here), s6dns_rci_free(&s6dns_rci_here))
+
+#endif
diff --git a/src/include/s6-dns/skadns.h b/src/include/s6-dns/skadns.h
new file mode 100644
index 0000000..d5ed82f
--- /dev/null
+++ b/src/include/s6-dns/skadns.h
@@ -0,0 +1,73 @@
+/* ISC license. */
+
+#ifndef SKADNS_H
+#define SKADNS_H
+
+#include <errno.h>
+#include <skalibs/config.h>
+#include <skalibs/uint16.h>
+#include <skalibs/uint32.h>
+#include <skalibs/tai.h>
+#include <skalibs/stralloc.h>
+#include <skalibs/genalloc.h>
+#include <skalibs/gensetdyn.h>
+#include <skalibs/skaclient.h>
+#include <s6-dns/config.h>
+#include <s6-dns/s6dns-domain.h>
+
+#define SKADNSD_PROG S6_DNS_BINPREFIX "skadnsd"
+#define SKADNS_BANNER1 "skadns v1.0 (b)\n"
+#define SKADNS_BANNER1_LEN (sizeof SKADNS_BANNER1 - 1)
+#define SKADNS_BANNER2 "skadns v1.0 (a)\n"
+#define SKADNS_BANNER2_LEN (sizeof SKADNS_BANNER2 - 1)
+#define SKADNS_MAXCONCURRENCY 1000
+
+typedef struct skadnsanswer_s skadnsanswer_t, *skadnsanswer_t_ref ;
+struct skadnsanswer_s
+{
+  int status ;
+  char *data ;
+  unsigned int len ;
+} ;
+#define SKADNSANSWER_ZERO { .status = EINVAL, .data = 0, .len = 0 }
+
+typedef struct skadns_s skadns_t, *skadns_t_ref ;
+struct skadns_s
+{
+  skaclient_t connection ;
+  genalloc list ; /* array of uint16 */
+  gensetdyn q ; /* set of skadnsanswer_t */
+  skaclient_buffer_t buffers ;
+} ;
+#define SKADNS_ZERO { .connection = SKACLIENT_ZERO, .list = GENALLOC_ZERO, .q = GENSETDYN_INIT(skadnsanswer_t, 3, 3, 8) }
+extern skadns_t const skadns_zero ;
+
+
+ /* Starting and ending a session */
+
+extern int skadns_start (skadns_t *, char const *, tain_t const *, tain_t *) ;
+#define skadns_start_g(a, path, deadline) skadns_start(a, path, (deadline), &STAMP)
+extern int skadns_startf (skadns_t *, tain_t const *, tain_t *) ;
+#define skadns_startf_g(a, deadline) skadns_startf(a, (deadline), &STAMP)
+extern void skadns_end (skadns_t *) ;
+
+                
+ /* Synchronous functions */
+ 
+extern int skadns_send (skadns_t *, uint16 *, s6dns_domain_t const *, uint16, tain_t const *, tain_t const *, tain_t *) ;
+#define skadns_send_g(a, id, d, qtype, limit, deadline) skadns_send(a, id, d, qtype, limit, (deadline), &STAMP)
+extern int skadns_cancel (skadns_t *, uint16, tain_t const *, tain_t *) ;
+#define skadns_cancel_g(a, id, deadline) skadns_cancel(a, id, (deadline), &STAMP)
+
+
+ /* Asynchronous functions */
+
+#define skadns_fd(a) skaclient_fd(&(a)->connection)
+extern int skadns_update (skadns_t *) ;
+#define skadns_list(a) genalloc_s(uint16 const, &(a)->list)
+#define skadns_clearlist(a) ((a)->list.len = 0)
+extern int skadns_packetlen (skadns_t const *, uint16) ;
+extern char const *skadns_packet (skadns_t const *, uint16) ;
+extern int skadns_release (skadns_t *, uint16) ;
+
+#endif
diff --git a/src/libs6dns/deps-lib/s6dns b/src/libs6dns/deps-lib/s6dns
new file mode 100755
index 0000000..b218652
--- /dev/null
+++ b/src/libs6dns/deps-lib/s6dns
@@ -0,0 +1,88 @@
+s6dns_constants_error.o
+s6dns_constants_error_str.o
+s6dns_debughook_zero.o
+s6dns_domain_arpafromip4.o
+s6dns_domain_arpafromip6.o
+s6dns_domain_decode.o
+s6dns_domain_encode.o
+s6dns_domain_encodelist.o
+s6dns_domain_fromstring.o
+s6dns_domain_fromstring_noqualify_encode.o
+s6dns_domain_fromstring_qualify_encode.o
+s6dns_domain_noqualify.o
+s6dns_domain_qualify.o
+s6dns_domain_tostring.o
+s6dns_engine.o
+s6dns_engine_free.o
+s6dns_engine_freen.o
+s6dns_engine_here.o
+s6dns_engine_nextdeadline.o
+s6dns_engine_zero.o
+s6dns_fmt_domainlist.o
+s6dns_fmt_hinfo.o
+s6dns_fmt_mx.o
+s6dns_fmt_soa.o
+s6dns_fmt_srv.o
+s6dns_message_counts_next.o
+s6dns_message_counts_pack.o
+s6dns_message_counts_unpack.o
+s6dns_message_counts_zero.o
+s6dns_message_get_domain.o
+s6dns_message_get_domain_internal.o
+s6dns_message_get_hinfo.o
+s6dns_message_get_string.o
+s6dns_message_get_string_internal.o
+s6dns_message_get_strings.o
+s6dns_message_get_mx.o
+s6dns_message_get_soa.o
+s6dns_message_get_srv.o
+s6dns_message_header_pack.o
+s6dns_message_header_unpack.o
+s6dns_message_header_zero.o
+s6dns_message_parse_answer_aaaa.o
+s6dns_message_parse_answer_a.o
+s6dns_message_parse_answer_domain.o
+s6dns_message_parse_answer_hinfo.o
+s6dns_message_parse_answer_mx.o
+s6dns_message_parse_answer_soa.o
+s6dns_message_parse_answer_srv.o
+s6dns_message_parse_answer_strings.o
+s6dns_message_parse.o
+s6dns_message_parse_getrr.o
+s6dns_message_parse_init.o
+s6dns_message_parse_next.o
+s6dns_message_parse_skipqd.o
+s6dns_rci_free.o
+s6dns_rci_here.o
+s6dns_rci_init.o
+s6dns_rci_zero.o
+s6dns_resolve_core.o
+s6dns_resolve_parse.o
+s6dns_resolven_loop.o
+s6dns_resolven_parse.o
+s6dns_resolve_dpag.o
+s6dns_resolve_mpag.o
+s6dns_resolve_name4.o
+s6dns_resolve_name6.o
+s6dns_resolvenoq.o
+s6dns_resolveq.o
+s6dns_resolvenoq_aaaaa.o
+s6dns_resolveq_aaaaa.o
+s6dns_analyze_packet.o
+s6dns_analyze_qtype_parse.o
+s6dns_analyze_record.o
+s6dns_analyze_record_a.o
+s6dns_analyze_record_aaaa.o
+s6dns_analyze_record_hinfo.o
+s6dns_analyze_record_mx.o
+s6dns_analyze_record_soa.o
+s6dns_analyze_record_srv.o
+s6dns_analyze_record_domain.o
+s6dns_analyze_record_strings.o
+s6dns_analyze_record_unknown.o
+s6dns_analyze_rtypetable.o
+s6dns_debug_dumpdt_stdout.o
+s6dns_debug_dumpdt_stderr.o
+s6dns_debug_dumpdt_post_recv.o
+s6dns_debug_dumpdt_pre_send.o
+s6dns_debug_dumpdt_post_send.o
diff --git a/src/libs6dns/s6dns-message-internal.h b/src/libs6dns/s6dns-message-internal.h
new file mode 100644
index 0000000..e0d10d6
--- /dev/null
+++ b/src/libs6dns/s6dns-message-internal.h
@@ -0,0 +1,12 @@
+/* ISC license. */
+
+#ifndef S6DNS_MESSAGE_INTERNAL_H
+#define S6DNS_MESSAGE_INTERNAL_H
+
+
+ /* Low-level packet parsing */
+
+extern int s6dns_message_get_string_internal (char *, unsigned int, char const *, unsigned int, unsigned int *) ;
+extern unsigned int s6dns_message_get_domain_internal (char *, unsigned int, char const *, unsigned int, unsigned int *) ;
+
+#endif
diff --git a/src/libs6dns/s6dns_analyze_packet.c b/src/libs6dns/s6dns_analyze_packet.c
new file mode 100644
index 0000000..57a5ce5
--- /dev/null
+++ b/src/libs6dns/s6dns_analyze_packet.c
@@ -0,0 +1,127 @@
+/* ISC license. */
+
+#include <errno.h>
+#include <skalibs/error.h>
+#include <skalibs/uint16.h>
+#include <skalibs/bytestr.h>
+#include <skalibs/genwrite.h>
+#include <skalibs/fmtscan.h>
+#include <s6-dns/s6dns-constants.h>
+#include <s6-dns/s6dns-domain.h>
+#include <s6-dns/s6dns-message.h>
+#include <s6-dns/s6dns-analyze.h>
+
+#define add(s) if ((*gp->put)(gp->target, (s), str_len(s)) < 0) return 0
+#define addfmt(n) if ((*gp->put)(gp->target, fmt, uint_fmt(fmt, (n))) < 0) return 0
+#define addfmt16(n) if ((*gp->put)(gp->target, fmt, uint16_fmt(fmt, (n))) < 0) return 0
+
+int s6dns_analyze_packet (genwrite_t *gp, char const *packet, unsigned int packetlen, int rec)
+{
+  s6dns_message_header_t h ;
+  s6dns_message_counts_t counts ;
+  unsigned int pos ;
+  unsigned int section ;
+  char fmt[UINT_FMT] ;
+  if (!s6dns_message_parse_init(&h, &counts, packet, packetlen, &pos))
+    return 0 ;
+
+  addfmt(packetlen) ;
+  add(" bytes, ") ;
+  addfmt16(counts.qd) ;
+  add("+") ;
+  addfmt16(counts.an) ;
+  add("+") ;
+  addfmt16(counts.ns) ;
+  add("+") ;
+  addfmt16(counts.nr) ;
+  add(" records") ;
+  if (h.qr) add(", response") ;
+  if (h.opcode)
+  {
+    add(", weird op (") ;
+    addfmt(h.opcode) ;
+    add(")") ;
+  }
+  if (h.aa) add(", authoritative") ;
+  if (h.tc) add(", truncated") ;
+  if (h.rd)
+  {
+    add(", ") ;
+    if (!rec) add("weird ") ;
+    add("rd") ;
+  }
+  if (h.ra)
+  {
+    add(", ") ;
+    if (!rec) add("weird ") ;
+    add("ra") ;
+  }
+  switch (h.rcode)
+  {
+    case 0 : add(", noerror") ; break ;
+    case 1 : add(", fmterror") ; break ;
+    case 2 : add(", servfail") ; break ;
+    case 3 : add(", nxdomain") ; break ;
+    case 4 : add(", notimpl") ; break ;
+    case 5 : add(", refused") ; break ;
+    default:
+    {
+      add(", weird rcode (") ;
+      addfmt(h.rcode) ;
+      add(")") ;
+    }
+  }
+  if (h.z)
+  {
+    add(", weird z (") ;
+    addfmt(h.z) ;
+    add(")") ;
+  }
+  add("\n") ;
+
+  for (;;)
+  {
+    s6dns_domain_t d ;
+    char buf[257] ;
+    unsigned int len ;
+    uint16 qtype ;
+    uint16 qclass ;
+    section = s6dns_message_counts_next(&counts) ;
+    if (section != 1) break ;
+    add("query: ") ;
+    if (!s6dns_message_get_domain(&d, packet, packetlen, &pos)) return 0 ;
+    len = s6dns_domain_tostring(buf, 255, &d) ;
+    if (!len) return 0 ;
+    buf[len++] = '\n' ; buf[len++] = 0 ;
+    if (pos + 4 > packetlen) return (errno = EPROTO, 0) ;
+    uint16_unpack_big(packet + pos, &qtype) ; pos += 2 ;
+    uint16_unpack_big(packet + pos, &qclass) ; pos += 2 ;
+    if (qclass != S6DNS_C_IN)
+    {
+      add("weird class (") ;
+      addfmt16(qclass) ;
+      add(") - ") ;
+    }
+    addfmt16(qtype) ;
+    add(" ") ;
+    add(buf) ;
+  }
+
+  while (section)
+  {
+    static char const *intro[3] = { "answer: ", "authority: ", "additional: " } ;
+    s6dns_message_rr_t rr ;
+    if (!s6dns_message_parse_getrr(&rr, packet, packetlen, &pos)) return 0 ;
+    add(intro[section-2]) ;
+    if (rr.rclass != S6DNS_C_IN)
+    {
+      add("weird class (") ;
+      addfmt16(rr.rclass) ;
+      add("), not attempting to analyze record\n") ;
+    }
+    else if (!s6dns_analyze_record(gp, &rr, packet, packetlen, pos)) return 0 ;
+    section = s6dns_message_parse_next(&counts, &rr, packet, packetlen, &pos) ;
+  }
+
+  return 1 ;
+}
diff --git a/src/libs6dns/s6dns_analyze_qtype_parse.c b/src/libs6dns/s6dns_analyze_qtype_parse.c
new file mode 100644
index 0000000..8c04137
--- /dev/null
+++ b/src/libs6dns/s6dns_analyze_qtype_parse.c
@@ -0,0 +1,46 @@
+/* ISC license. */
+
+#include <skalibs/uint16.h>
+#include <skalibs/bytestr.h>
+#include <s6-dns/s6dns-constants.h>
+#include <s6-dns/s6dns-analyze.h>
+
+typedef struct lookuptable_s lookuptable_t, *lookuptable_t_ref ;
+struct lookuptable_s
+{
+  char const *text ;
+  uint16 qtype ;
+} ;
+
+static lookuptable_t const table[] =
+{
+  { "ANY", S6DNS_T_ANY },
+  { "A", S6DNS_T_A },
+  { "NS", S6DNS_T_NS },
+  { "CNAME", S6DNS_T_CNAME },
+  { "SOA", S6DNS_T_SOA },
+  { "PTR", S6DNS_T_PTR },
+  { "HINFO", S6DNS_T_HINFO },
+  { "MX", S6DNS_T_MX },
+  { "TXT", S6DNS_T_TXT },
+  { "AAAA", S6DNS_T_AAAA },
+  { "SRV", S6DNS_T_SRV },
+  { "RP", S6DNS_T_RP },
+  { "SIG", S6DNS_T_SIG },
+  { "KEY", S6DNS_T_KEY },
+  { "AXFR", S6DNS_T_AXFR },
+  { 0, 0 }
+} ;
+
+uint16 s6dns_analyze_qtype_parse (char const *s)
+{
+  {
+    uint16 u ;
+    if (uint160_scan(s, &u)) return u ;
+  }
+  {
+    register lookuptable_t const *p = table ;
+    for (; p->text ; p++) if (case_equals(s, p->text)) return p->qtype ;
+  }
+  return 0 ;
+}
diff --git a/src/libs6dns/s6dns_analyze_record.c b/src/libs6dns/s6dns_analyze_record.c
new file mode 100644
index 0000000..dd2e7d2
--- /dev/null
+++ b/src/libs6dns/s6dns_analyze_record.c
@@ -0,0 +1,37 @@
+/* ISC license. */
+
+#include <skalibs/uint16.h>
+#include <skalibs/uint32.h>
+#include <skalibs/bytestr.h>
+#include <skalibs/genwrite.h>
+#include <s6-dns/s6dns-domain.h>
+#include <s6-dns/s6dns-message.h>
+#include <s6-dns/s6dns-analyze.h>
+
+static s6dns_analyze_rtypetable_t const *rtypelookup (uint16 rtype)
+{
+  register s6dns_analyze_rtypetable_t const *wut = s6dns_analyze_rtypetable ;
+  while (wut->rtype && wut->rtype != rtype) wut++ ;
+  return wut ;
+}
+
+int s6dns_analyze_record (genwrite_t *gp, s6dns_message_rr_t const *rr, char const *packet, unsigned int packetlen, unsigned int pos)
+{
+  s6dns_analyze_rtypetable_t const *wut = rtypelookup(rr->rtype) ;
+  {
+    char buf[256] ;
+    register unsigned int n = s6dns_domain_tostring(buf, 256, &rr->name) ;
+    if (!n) return 0 ;
+    if ((*gp->put)(gp->target, buf, n) < 0) return 0 ;
+  }
+  {
+    char fmt[UINT32_FMT+1] = " " ;
+    if ((*gp->put)(gp->target, fmt, 1 + uint32_fmt(fmt+1, rr->ttl)) < 0) return 0 ;
+  }
+  if ((*gp->put)(gp->target, " ", 1) < 0) return 0 ;
+  if ((*gp->put)(gp->target, wut->string, str_len(wut->string)) < 0) return 0 ;
+  if ((*gp->put)(gp->target, " ", 1) < 0) return 0 ;
+  if (!(*wut->f)(gp, rr, packet, packetlen, pos)) return 0 ;
+  if ((*gp->put)(gp->target, "\n", 1) < 0) return 0 ;
+  return 1 ;
+}
diff --git a/src/libs6dns/s6dns_analyze_record_a.c b/src/libs6dns/s6dns_analyze_record_a.c
new file mode 100644
index 0000000..5e374cb
--- /dev/null
+++ b/src/libs6dns/s6dns_analyze_record_a.c
@@ -0,0 +1,17 @@
+/* ISC license. */
+
+#include <errno.h>
+#include <skalibs/error.h>
+#include <skalibs/genwrite.h>
+#include <skalibs/fmtscan.h>
+#include <s6-dns/s6dns-message.h>
+#include <s6-dns/s6dns-analyze.h>
+
+int s6dns_analyze_record_a (genwrite_t *gp, s6dns_message_rr_t const *rr, char const *packet, unsigned int packetlen, unsigned int pos)
+{
+  char fmt[IP4_FMT] ;
+  if (rr->rdlength != 4) return (errno = EPROTO, 0) ;
+  if (pos + 4 > packetlen) return (errno = EPROTO, 0) ;
+  if ((*gp->put)(gp->target, fmt, ip4_fmt(fmt, packet + pos)) < 0) return 0 ;
+  return 1 ;
+}
diff --git a/src/libs6dns/s6dns_analyze_record_aaaa.c b/src/libs6dns/s6dns_analyze_record_aaaa.c
new file mode 100644
index 0000000..495ba24
--- /dev/null
+++ b/src/libs6dns/s6dns_analyze_record_aaaa.c
@@ -0,0 +1,17 @@
+/* ISC license. */
+
+#include <errno.h>
+#include <skalibs/error.h>
+#include <skalibs/genwrite.h>
+#include <skalibs/fmtscan.h>
+#include <s6-dns/s6dns-message.h>
+#include <s6-dns/s6dns-analyze.h>
+
+int s6dns_analyze_record_aaaa (genwrite_t *gp, s6dns_message_rr_t const *rr, char const *packet, unsigned int packetlen, unsigned int pos)
+{
+  char fmt[IP6_FMT] ;
+  if (rr->rdlength != 16) return (errno = EPROTO, 0) ;
+  if (pos + 16 > packetlen) return (errno = EPROTO, 0) ;
+  if ((*gp->put)(gp->target, fmt, ip6_fmt(fmt, packet + pos)) < 0) return 0 ;
+  return 1 ;
+}
diff --git a/src/libs6dns/s6dns_analyze_record_domain.c b/src/libs6dns/s6dns_analyze_record_domain.c
new file mode 100644
index 0000000..f645dca
--- /dev/null
+++ b/src/libs6dns/s6dns_analyze_record_domain.c
@@ -0,0 +1,23 @@
+/* ISC license. */
+
+#include <errno.h>
+#include <skalibs/error.h>
+#include <skalibs/genwrite.h>
+#include <s6-dns/s6dns-domain.h>
+#include <s6-dns/s6dns-message.h>
+#include <s6-dns/s6dns-fmt.h>
+#include <s6-dns/s6dns-analyze.h>
+
+int s6dns_analyze_record_domain (genwrite_t *gp, s6dns_message_rr_t const *rr, char const *packet, unsigned int packetlen, unsigned int start)
+{
+  s6dns_domain_t d ;
+  char buf[S6DNS_FMT_DOMAIN] ;
+  unsigned int pos = start ;
+  register unsigned int len ;
+  if (!s6dns_message_get_domain(&d, packet, packetlen, &pos)) return 0 ;
+  if (rr->rdlength != pos - start) return (errno = EPROTO, 0) ;
+  len = s6dns_fmt_domain(buf, 256, &d) ;
+  if (!len) return 0 ;
+  if ((*gp->put)(gp->target, buf, len) < 0) return 0 ;
+  return 1 ;
+}
diff --git a/src/libs6dns/s6dns_analyze_record_hinfo.c b/src/libs6dns/s6dns_analyze_record_hinfo.c
new file mode 100644
index 0000000..38d13d9
--- /dev/null
+++ b/src/libs6dns/s6dns_analyze_record_hinfo.c
@@ -0,0 +1,22 @@
+/* ISC license. */
+
+#include <errno.h>
+#include <skalibs/error.h>
+#include <skalibs/genwrite.h>
+#include <s6-dns/s6dns-message.h>
+#include <s6-dns/s6dns-fmt.h>
+#include <s6-dns/s6dns-analyze.h>
+
+int s6dns_analyze_record_hinfo (genwrite_t *gp, s6dns_message_rr_t const *rr, char const *packet, unsigned int packetlen, unsigned int start)
+{
+  s6dns_message_rr_hinfo_t hinfo ;
+  char buf[S6DNS_FMT_HINFO] ;
+  unsigned int pos = start ;
+  unsigned int len ;
+  if (!s6dns_message_get_hinfo(&hinfo, packet, packetlen, &pos)) return 0 ;
+  if (rr->rdlength != pos - start) return (errno = EPROTO, 0) ;
+  len = s6dns_fmt_hinfo(buf, S6DNS_FMT_HINFO, &hinfo) ;
+  if (!len) return 0 ;
+  if ((*gp->put)(gp->target, buf, len) < 0) return 0 ;
+  return 1 ;
+}
diff --git a/src/libs6dns/s6dns_analyze_record_mx.c b/src/libs6dns/s6dns_analyze_record_mx.c
new file mode 100644
index 0000000..adf9995
--- /dev/null
+++ b/src/libs6dns/s6dns_analyze_record_mx.c
@@ -0,0 +1,22 @@
+/* ISC license. */
+
+#include <errno.h>
+#include <skalibs/error.h>
+#include <skalibs/genwrite.h>
+#include <s6-dns/s6dns-message.h>
+#include <s6-dns/s6dns-fmt.h>
+#include <s6-dns/s6dns-analyze.h>
+
+int s6dns_analyze_record_mx (genwrite_t *gp, s6dns_message_rr_t const *rr, char const *packet, unsigned int packetlen, unsigned int start)
+{
+  s6dns_message_rr_mx_t mx ;
+  char buf[S6DNS_FMT_MX] ;
+  unsigned int pos = start ;
+  unsigned int len ;
+  if (!s6dns_message_get_mx(&mx, packet, packetlen, &pos)) return 0 ;
+  if (rr->rdlength != pos - start) return (errno = EPROTO, 0) ;
+  len = s6dns_fmt_mx(buf, S6DNS_FMT_MX, &mx) ;
+  if (!len) return 0 ;
+  if ((*gp->put)(gp->target, buf, len) < 0) return 0 ;
+  return 1 ;
+}
diff --git a/src/libs6dns/s6dns_analyze_record_soa.c b/src/libs6dns/s6dns_analyze_record_soa.c
new file mode 100644
index 0000000..68fc55f
--- /dev/null
+++ b/src/libs6dns/s6dns_analyze_record_soa.c
@@ -0,0 +1,22 @@
+/* ISC license. */
+
+#include <errno.h>
+#include <skalibs/error.h>
+#include <skalibs/genwrite.h>
+#include <s6-dns/s6dns-message.h>
+#include <s6-dns/s6dns-fmt.h>
+#include <s6-dns/s6dns-analyze.h>
+
+int s6dns_analyze_record_soa (genwrite_t *gp, s6dns_message_rr_t const *rr, char const *packet, unsigned int packetlen, unsigned int start)
+{
+  s6dns_message_rr_soa_t soa ;
+  char buf[S6DNS_FMT_SOA] ;
+  unsigned int pos = start ;
+  unsigned int len ;
+  if (!s6dns_message_get_soa(&soa, packet, packetlen, &pos)) return 0 ;
+  if (rr->rdlength != pos - start) return (errno = EPROTO, 0) ;
+  len = s6dns_fmt_soa(buf, S6DNS_FMT_SOA, &soa) ;
+  if (!len) return 0 ;
+  if ((*gp->put)(gp->target, buf, len) < 0) return 0 ;
+  return 1 ;
+}
diff --git a/src/libs6dns/s6dns_analyze_record_srv.c b/src/libs6dns/s6dns_analyze_record_srv.c
new file mode 100644
index 0000000..9ce5b6e
--- /dev/null
+++ b/src/libs6dns/s6dns_analyze_record_srv.c
@@ -0,0 +1,22 @@
+/* ISC license. */
+
+#include <errno.h>
+#include <skalibs/error.h>
+#include <skalibs/genwrite.h>
+#include <s6-dns/s6dns-message.h>
+#include <s6-dns/s6dns-fmt.h>
+#include <s6-dns/s6dns-analyze.h>
+
+int s6dns_analyze_record_srv (genwrite_t *gp, s6dns_message_rr_t const *rr, char const *packet, unsigned int packetlen, unsigned int start)
+{
+  s6dns_message_rr_srv_t srv ;
+  char buf[S6DNS_FMT_SRV] ;
+  unsigned int pos = start ;
+  unsigned int len ;
+  if (!s6dns_message_get_srv(&srv, packet, packetlen, &pos)) return 0 ;
+  if (rr->rdlength != pos - start) return (errno = EPROTO, 0) ;
+  len = s6dns_fmt_srv(buf, S6DNS_FMT_SRV, &srv) ;
+  if (!len) return 0 ;
+  if ((*gp->put)(gp->target, buf, len) < 0) return 0 ;
+  return 1 ;
+}
diff --git a/src/libs6dns/s6dns_analyze_record_strings.c b/src/libs6dns/s6dns_analyze_record_strings.c
new file mode 100644
index 0000000..c2aa15a
--- /dev/null
+++ b/src/libs6dns/s6dns_analyze_record_strings.c
@@ -0,0 +1,23 @@
+/* ISC license. */
+
+#include <errno.h>
+#include <skalibs/error.h>
+#include <skalibs/stralloc.h>
+#include <skalibs/genwrite.h>
+#include <skalibs/skamisc.h>
+#include <s6-dns/s6dns-message.h>
+#include <s6-dns/s6dns-analyze.h>
+
+int s6dns_analyze_record_strings (genwrite_t *gp, s6dns_message_rr_t const *rr, char const *packet, unsigned int packetlen, unsigned int start)
+{
+  stralloc sa = STRALLOC_ZERO ;
+  char buf[rr->rdlength] ;
+  unsigned int pos = start ;
+  register int r = s6dns_message_get_strings(buf, rr->rdlength, packet, packetlen, &pos) ;
+  if (r < 0) return 0 ;
+  if (rr->rdlength != pos - start) return (errno = EPROTO, 0) ;
+  if (!string_quote(&sa, buf, r)) return 0 ;
+  r = (*gp->put)(gp->target, sa.s, sa.len) >= 0 ;
+  stralloc_free(&sa) ;
+  return r ;
+}
diff --git a/src/libs6dns/s6dns_analyze_record_unknown.c b/src/libs6dns/s6dns_analyze_record_unknown.c
new file mode 100644
index 0000000..b5e458e
--- /dev/null
+++ b/src/libs6dns/s6dns_analyze_record_unknown.c
@@ -0,0 +1,25 @@
+/* ISC license. */
+
+#include <skalibs/uint16.h>
+#include <skalibs/fmtscan.h>
+#include <skalibs/genwrite.h>
+#include <s6-dns/s6dns-message.h>
+#include <s6-dns/s6dns-analyze.h>
+
+int s6dns_analyze_record_unknown (genwrite_t *gp, s6dns_message_rr_t const *rr, char const *packet, unsigned int packetlen, unsigned int pos)
+{
+  char fmt[UINT16_FMT] ;
+  if ((*gp->put)(gp->target, "rtype ", 6) < 0) return 0 ;
+  if ((*gp->put)(gp->target, fmt, uint16_fmt(fmt, rr->rtype)) < 0) return 0 ;
+  if ((*gp->put)(gp->target, " length ", 8) < 0) return 0 ;
+  if ((*gp->put)(gp->target, fmt, uint16_fmt(fmt, rr->rdlength)) < 0) return 0 ;
+  if ((*gp->put)(gp->target, ": ", 2) < 0) return 0 ;
+  {
+    register uint16 i = 0 ;
+    for (; i < rr->rdlength ; i++)
+      if ((*gp->put)(gp->target, fmt, ucharn_fmt(fmt, packet + pos + i, 1)) < 0)
+        return 0 ;
+  }
+  (void)packetlen ;
+  return 1 ;
+}
diff --git a/src/libs6dns/s6dns_analyze_rtypetable.c b/src/libs6dns/s6dns_analyze_rtypetable.c
new file mode 100644
index 0000000..523fc72
--- /dev/null
+++ b/src/libs6dns/s6dns_analyze_rtypetable.c
@@ -0,0 +1,20 @@
+/* ISC license. */
+
+#include <s6-dns/s6dns-analyze.h>
+
+static s6dns_analyze_rtypetable_t const s6dns_analyze_rtypetable_array[] =
+{
+  { 1, "A", &s6dns_analyze_record_a },
+  { 2, "NS", &s6dns_analyze_record_domain },
+  { 5, "CNAME", &s6dns_analyze_record_domain },
+  { 6, "SOA", &s6dns_analyze_record_soa },
+  { 12, "PTR", &s6dns_analyze_record_domain },
+  { 13, "HINFO", &s6dns_analyze_record_hinfo },
+  { 15, "MX", &s6dns_analyze_record_mx },
+  { 16, "TXT", &s6dns_analyze_record_strings },
+  { 28, "AAAA", &s6dns_analyze_record_aaaa },
+  { 33, "SRV", &s6dns_analyze_record_srv },
+  { 0, "unknown", &s6dns_analyze_record_unknown }
+} ;
+
+s6dns_analyze_rtypetable_t const *s6dns_analyze_rtypetable = s6dns_analyze_rtypetable_array ;
diff --git a/src/libs6dns/s6dns_constants_error.c b/src/libs6dns/s6dns_constants_error.c
new file mode 100644
index 0000000..d5e4bcb
--- /dev/null
+++ b/src/libs6dns/s6dns_constants_error.c
@@ -0,0 +1,23 @@
+/* ISC license. */
+
+#include <errno.h>
+#include <skalibs/error.h>
+#include <s6-dns/s6dns-constants.h>
+
+static s6dns_constants_error_message_t const array[] =
+{
+  { ENETUNREACH, "no available DNS server" },
+  { EBADMSG, "server did not understand query" },
+  { EBUSY, "server failure" },
+  { ENOENT, "no such domain" },
+  { ENOTSUP, "not implemented in server" },
+  { ECONNREFUSED, "server refused" },
+  { EIO, "unknown network error" },
+  { EAGAIN, "query still processing" },
+  { ETIMEDOUT, "query timed out" },
+  { EPROTO, "malformed packet" },
+  { EDOM, "internal error (please submit a bug-report)" },
+  { -1, "unknown error" }
+} ;
+
+s6dns_constants_error_message_t const *const s6dns_constants_error = array ;
diff --git a/src/libs6dns/s6dns_constants_error_str.c b/src/libs6dns/s6dns_constants_error_str.c
new file mode 100644
index 0000000..9dda1a7
--- /dev/null
+++ b/src/libs6dns/s6dns_constants_error_str.c
@@ -0,0 +1,11 @@
+/* ISC license. */
+
+#include <skalibs/error.h>
+#include <s6-dns/s6dns-constants.h>
+
+char const *s6dns_constants_error_str (int e)
+{
+  s6dns_constants_error_message_t *p = s6dns_constants_error ;
+  while ((p->num != e) && (p->num != -1)) p++ ;
+  return p->num == -1 ? error_str(e) : p->string ;
+}
diff --git a/src/libs6dns/s6dns_debug_dumpdt_post_recv.c b/src/libs6dns/s6dns_debug_dumpdt_post_recv.c
new file mode 100644
index 0000000..5680489
--- /dev/null
+++ b/src/libs6dns/s6dns_debug_dumpdt_post_recv.c
@@ -0,0 +1,14 @@
+/* ISC license */
+
+#include <skalibs/genwrite.h>
+#include <s6-dns/s6dns-engine.h>
+#include <s6-dns/s6dns-debug.h>
+
+int s6dns_debug_dumpdt_post_recv (s6dns_engine_t const *dt, void *data)
+{
+  genwrite_t *gp = data ;
+  (void)dt ;
+  if ((*gp->put)(gp->target, "Received a packet\n", 19) < 19) return 0 ;
+  if ((*gp->put)(gp->target, "\n", 1) < 1) return 0 ;
+  return (*gp->flush)(gp->target) ;
+}
diff --git a/src/libs6dns/s6dns_debug_dumpdt_post_send.c b/src/libs6dns/s6dns_debug_dumpdt_post_send.c
new file mode 100644
index 0000000..e41d595
--- /dev/null
+++ b/src/libs6dns/s6dns_debug_dumpdt_post_send.c
@@ -0,0 +1,30 @@
+/* ISC license */
+
+#include <skalibs/uint16.h>
+#include <skalibs/djbtime.h>
+#include <skalibs/genwrite.h>
+#include <s6-dns/s6dns-engine.h>
+#include <s6-dns/s6dns-debug.h>
+
+int s6dns_debug_dumpdt_post_send (s6dns_engine_t const *dt, void *data)
+{
+  genwrite_t *gp = data ;
+  char buf[LOCALTMN_FMT] ;
+  unsigned int len ;
+  if ((*gp->put)(gp->target, "Sent query ", 11) < 11) return 0 ;
+  {
+    uint16 id ;
+    uint16_unpack_big(dt->sa.s + 2, &id) ;
+    len = uint16_fmt(buf, id) ;
+  }
+  if ((*gp->put)(gp->target, buf, len) < (int)len) return 0 ;
+  if ((*gp->put)(gp->target, " - next recv deadline is ", 25) < 25) return 0 ;
+  {
+    localtmn_t l ;
+    if (!localtmn_from_tain(&l, &dt->localdeadline, 0)) return 0 ;
+    len = localtmn_fmt(buf, &l) ;
+  }
+  if ((*gp->put)(gp->target, buf, len) < (int)len) return 0 ;
+  if ((*gp->put)(gp->target, "\n\n", 2) < 2) return 0 ;
+  return (*gp->flush)(gp->target) ;
+}
diff --git a/src/libs6dns/s6dns_debug_dumpdt_pre_send.c b/src/libs6dns/s6dns_debug_dumpdt_pre_send.c
new file mode 100644
index 0000000..df8131d
--- /dev/null
+++ b/src/libs6dns/s6dns_debug_dumpdt_pre_send.c
@@ -0,0 +1,59 @@
+/* ISC license */
+
+#include <errno.h>
+#include <skalibs/uint16.h>
+#include <skalibs/fmtscan.h>
+#include <skalibs/tai.h>
+#include <skalibs/djbtime.h>
+#include <skalibs/genwrite.h>
+#include <skalibs/ip46.h>
+#include <s6-dns/s6dns-constants.h>
+#include <s6-dns/s6dns-ip46.h>
+#include <s6-dns/s6dns-engine.h>
+#include <s6-dns/s6dns-analyze.h>
+#include <s6-dns/s6dns-debug.h>
+
+#ifdef SKALIBS_IPV6_ENABLED
+# define s6dns_ipfmt(buf, ip, is6) ((is6) ? ip6_fmt(buf, ip) : ip4_fmt(buf, ip))
+#else
+# define s6dns_ipfmt(buf, ip, is6) ip4_fmt(buf, ip)
+#endif
+
+int s6dns_debug_dumpdt_pre_send (s6dns_engine_t const *dt, void *data)
+{
+  genwrite_t *gp = data ;
+  char buf[LOCALTMN_FMT] ;
+  unsigned int len ;
+  if ((*gp->put)(gp->target, "Preparing to send via ", 22) < 22) return 0 ;
+  if ((*gp->put)(gp->target, dt->flagtcp ? "TCP" : "UDP", 3) < 3) return 0 ;
+  if ((*gp->put)(gp->target, " to ", 4) < 4) return 0 ;
+  len = dt->sa.s[4] & 1 ;
+  if ((*gp->put)(gp->target, len ? "cache" : "server", len ? 5 : 6) < (len ? 5 : 6)) return 0 ;
+  if ((*gp->put)(gp->target, " ", 1) < 1) return 0 ;
+  len = s6dns_ipfmt(buf, s6dns_ip46list_ip(&dt->servers, dt->curserver), s6dns_ip46list_is6(&dt->servers, dt->curserver)) ;
+  if ((*gp->put)(gp->target, buf, len) < (int)len) return 0 ;
+  if ((*gp->put)(gp->target, " with deadline ", 15) < 15) return 0 ;
+  {
+    localtmn_t l ;
+    if (!localtmn_from_tain(&l, &dt->localdeadline, 0))
+    {
+      if (errno != EOVERFLOW) return 0 ;
+      byte_copy(buf, 10, "\"infinite\"") ; len = 10 ;
+    }
+    else len = localtmn_fmt(buf, &l) ;
+  }
+  if ((*gp->put)(gp->target, buf, len) < (int)len) return 0 ;
+  if ((*gp->put)(gp->target, ", ", 2) < 2) return 0 ;
+  if (dt->flagstrict && (*gp->put)(gp->target, "strict, ", 8) < 8) return 0 ;
+  if ((*gp->put)(gp->target, "query id ", 9) < 9) return 0 ;
+  {
+    uint16 id ;
+    uint16_unpack_big(dt->sa.s + 2, &id) ;
+    len = uint16_fmt(buf, id) ;
+  }
+  if ((*gp->put)(gp->target, buf, len) < (int)len) return 0 ;
+  if ((*gp->put)(gp->target, ":\n", 2) < 2) return 0 ;
+  if (!s6dns_analyze_packet(gp, dt->sa.s + 2, dt->querylen - 2, 1)) return 0 ;
+  if ((*gp->put)(gp->target, "\n", 1) < 1) return 0 ;
+  return (*gp->flush)(gp->target) ;
+}
diff --git a/src/libs6dns/s6dns_debug_dumpdt_stderr.c b/src/libs6dns/s6dns_debug_dumpdt_stderr.c
new file mode 100644
index 0000000..46bdbea
--- /dev/null
+++ b/src/libs6dns/s6dns_debug_dumpdt_stderr.c
@@ -0,0 +1,7 @@
+/* ISC license */
+
+#include <skalibs/genwrite.h>
+#include <s6-dns/s6dns-engine.h>
+#include <s6-dns/s6dns-debug.h>
+
+s6dns_debughook_t const s6dns_debug_dumpdt_stderr = S6DNS_DEBUG_DUMPDT_INIT((void *)&genwrite_stderr) ;
diff --git a/src/libs6dns/s6dns_debug_dumpdt_stdout.c b/src/libs6dns/s6dns_debug_dumpdt_stdout.c
new file mode 100644
index 0000000..9862549
--- /dev/null
+++ b/src/libs6dns/s6dns_debug_dumpdt_stdout.c
@@ -0,0 +1,7 @@
+/* ISC license */
+
+#include <skalibs/genwrite.h>
+#include <s6-dns/s6dns-engine.h>
+#include <s6-dns/s6dns-debug.h>
+
+s6dns_debughook_t const s6dns_debug_dumpdt_stdout = S6DNS_DEBUG_DUMPDT_INIT((void *)&genwrite_stdout) ;
diff --git a/src/libs6dns/s6dns_debughook_zero.c b/src/libs6dns/s6dns_debughook_zero.c
new file mode 100644
index 0000000..f3006b2
--- /dev/null
+++ b/src/libs6dns/s6dns_debughook_zero.c
@@ -0,0 +1,5 @@
+/* ISC license. */
+
+#include <s6-dns/s6dns-engine.h>
+
+s6dns_debughook_t const s6dns_debughook_zero = S6DNS_DEBUGHOOK_ZERO ;
diff --git a/src/libs6dns/s6dns_domain_arpafromip4.c b/src/libs6dns/s6dns_domain_arpafromip4.c
new file mode 100644
index 0000000..d77938f
--- /dev/null
+++ b/src/libs6dns/s6dns_domain_arpafromip4.c
@@ -0,0 +1,19 @@
+/* ISC license. */
+
+#include <skalibs/bytestr.h>
+#include <skalibs/uint.h>
+#include <s6-dns/s6dns-domain.h>
+
+void s6dns_domain_arpafromip4 (s6dns_domain_t *d, char const *ip)
+{
+  register unsigned int i = 0 ;
+  d->len = 0 ;
+  d->s[d->len++] = '.' ;  
+  for (; i < 4 ; i++)
+  {
+    register unsigned int u = ((unsigned char *)ip)[3-i] ;
+    d->len += uint_fmt(d->s + d->len, u) ;
+    d->s[d->len++] = '.' ;
+  }
+  byte_copy(d->s + d->len, 13, "in-addr.arpa.") ; d->len += 13 ;
+}
diff --git a/src/libs6dns/s6dns_domain_arpafromip6.c b/src/libs6dns/s6dns_domain_arpafromip6.c
new file mode 100644
index 0000000..3b58127
--- /dev/null
+++ b/src/libs6dns/s6dns_domain_arpafromip6.c
@@ -0,0 +1,21 @@
+/* ISC license. */
+
+#include <skalibs/bytestr.h>
+#include <skalibs/fmtscan.h>
+#include <s6-dns/s6dns-domain.h>
+
+void s6dns_domain_arpafromip6 (s6dns_domain_t *d, char const *ip6, unsigned int mask)
+{
+  register unsigned int i ;
+  if (mask > 128) mask = 128 ;
+  mask = mask ? 1 + ((mask-1) >> 2) : 0 ;
+  d->len = 0 ;
+  d->s[d->len++] = '.' ;
+  for (i = 32 - mask ; i < 32 ; i++)
+  {
+    unsigned char c = ip6[15-(i>>1)] ;
+    d->s[d->len++] = fmtscan_asc((i & 1) ? (c >> 4) : (c & 15)) ;
+    d->s[d->len++] = '.' ;
+  }
+  byte_copy(d->s + d->len, 9, "ip6.arpa.") ; d->len += 9 ;
+}
diff --git a/src/libs6dns/s6dns_domain_decode.c b/src/libs6dns/s6dns_domain_decode.c
new file mode 100644
index 0000000..db4ccf5
--- /dev/null
+++ b/src/libs6dns/s6dns_domain_decode.c
@@ -0,0 +1,30 @@
+/* ISC license. */
+
+#include <errno.h>
+#include <skalibs/error.h>
+#include <skalibs/bytestr.h>
+#include <s6-dns/s6dns-domain.h>
+
+static inline unsigned int s6dns_domain_label_decode (char *s, unsigned int max)
+{
+  unsigned int len = *(unsigned char *)s ;
+  if ((len > 63) || (len >= max)) return (errno = EPROTO, 0) ;
+  *s = '.' ;
+  case_lowerb(s+1, len) ;
+  return len + 1 ;
+}
+
+int s6dns_domain_decode (s6dns_domain_t *d)
+{
+  unsigned int max = 255 ;
+  unsigned int pos = 0 ;
+  for (;;)
+  {
+    register unsigned int r = s6dns_domain_label_decode(d->s + pos, max - pos) ;
+    if (!r) return 0 ;
+    pos += r ;
+    if (r == 1) break ;
+  }
+  d->len = pos ;
+  return 1 ;
+}
diff --git a/src/libs6dns/s6dns_domain_encode.c b/src/libs6dns/s6dns_domain_encode.c
new file mode 100644
index 0000000..61a790d
--- /dev/null
+++ b/src/libs6dns/s6dns_domain_encode.c
@@ -0,0 +1,21 @@
+/* ISC license. */
+
+#include <errno.h>
+#include <skalibs/bytestr.h>
+#include <s6-dns/s6dns-domain.h>
+
+int s6dns_domain_encode (s6dns_domain_t *d)
+{
+  register char *s = d->s ;
+  register unsigned int len = d->len ;
+  if (!d->len || (*s != '.')) return (errno = EINVAL, 0) ;
+  while (len > 1)
+  {
+    register unsigned int n = byte_chr(s + 1, len - 1, '.') ;
+    if (n > 63) return (errno = EINVAL, 0) ;
+    *s = n++ ; s += n ; len -= n ;
+  }
+  if (!len) return (errno = EINVAL, 0) ;
+  *s = 0 ;
+  return 1 ;
+}
diff --git a/src/libs6dns/s6dns_domain_encodelist.c b/src/libs6dns/s6dns_domain_encodelist.c
new file mode 100644
index 0000000..23b4570
--- /dev/null
+++ b/src/libs6dns/s6dns_domain_encodelist.c
@@ -0,0 +1,11 @@
+/* ISC license. */
+
+#include <s6-dns/s6dns-domain.h>
+
+unsigned int s6dns_domain_encodelist (s6dns_domain_t *list, unsigned int n)
+{
+  register unsigned int i = 0 ;
+  for (; i < n ; i++)
+    if (!s6dns_domain_encode(list + i)) break ;
+  return i ;
+}
diff --git a/src/libs6dns/s6dns_domain_fromstring.c b/src/libs6dns/s6dns_domain_fromstring.c
new file mode 100644
index 0000000..9346e24
--- /dev/null
+++ b/src/libs6dns/s6dns_domain_fromstring.c
@@ -0,0 +1,30 @@
+/* ISC license. */
+
+#include <errno.h>
+#include <skalibs/bytestr.h>
+#include <s6-dns/s6dns-domain.h>
+
+int s6dns_domain_fromstring (s6dns_domain_t *d, char const *s, unsigned int len)
+{
+  register unsigned int j = 1 ;
+  register unsigned int i = 0 ;
+  register unsigned int lastdot = 0 ;
+  d->s[0] = '.' ;
+  for (; i < len ; i++)
+  {
+    if (lastdot)
+    {
+      if ((j >= 255) || (lastdot++ >= 64)) return (errno = ENAMETOOLONG, 0) ;
+      d->s[j++] = s[i] ;
+    }
+    if (s[i] == '.') lastdot = 0 ;
+    else if (!lastdot)
+    {
+      i-- ;
+      lastdot = 1 ;
+    }
+  }
+  case_lowerb(d->s + 1, j-1) ;
+  d->len = j ;
+  return 1 ;
+}
diff --git a/src/libs6dns/s6dns_domain_fromstring_noqualify_encode.c b/src/libs6dns/s6dns_domain_fromstring_noqualify_encode.c
new file mode 100644
index 0000000..a12f979
--- /dev/null
+++ b/src/libs6dns/s6dns_domain_fromstring_noqualify_encode.c
@@ -0,0 +1,10 @@
+/* ISC license. */
+
+#include <s6-dns/s6dns-domain.h>
+
+int s6dns_domain_fromstring_noqualify_encode (s6dns_domain_t *d, char const *name, unsigned int len)
+{
+  return s6dns_domain_fromstring(d, name, len)
+   && s6dns_domain_noqualify(d)
+   && s6dns_domain_encode(d) ;
+}
diff --git a/src/libs6dns/s6dns_domain_fromstring_qualify_encode.c b/src/libs6dns/s6dns_domain_fromstring_qualify_encode.c
new file mode 100644
index 0000000..dbdea02
--- /dev/null
+++ b/src/libs6dns/s6dns_domain_fromstring_qualify_encode.c
@@ -0,0 +1,10 @@
+/* ISC license. */
+
+#include <s6-dns/s6dns-domain.h>
+
+unsigned int s6dns_domain_fromstring_qualify_encode (s6dns_domain_t *list, char const *name, unsigned int len, char const *rules, unsigned int rulesnum)
+{
+  s6dns_domain_t d ;
+  if (!s6dns_domain_fromstring(&d, name, len)) return 0 ;
+  return s6dns_domain_encodelist(list, s6dns_domain_qualify(list, &d, rules, rulesnum)) ;
+}
diff --git a/src/libs6dns/s6dns_domain_noqualify.c b/src/libs6dns/s6dns_domain_noqualify.c
new file mode 100644
index 0000000..4f91171
--- /dev/null
+++ b/src/libs6dns/s6dns_domain_noqualify.c
@@ -0,0 +1,14 @@
+/* ISC license. */
+
+#include <errno.h>
+#include <s6-dns/s6dns-domain.h>
+
+int s6dns_domain_noqualify (s6dns_domain_t *d)
+{
+  if (d->s[d->len-1] != '.')
+  {
+    if (d->len == 255) return (errno = ENAMETOOLONG, 0) ;
+    d->s[d->len++] = '.' ;
+  }
+  return 1 ;
+}
diff --git a/src/libs6dns/s6dns_domain_qualify.c b/src/libs6dns/s6dns_domain_qualify.c
new file mode 100644
index 0000000..6194ab5
--- /dev/null
+++ b/src/libs6dns/s6dns_domain_qualify.c
@@ -0,0 +1,30 @@
+/* ISC license. */
+
+#include <errno.h>
+#include <skalibs/bytestr.h>
+#include <s6-dns/s6dns-domain.h>
+
+unsigned int s6dns_domain_qualify (s6dns_domain_t *list, s6dns_domain_t const *d, char const *rules, unsigned int rulesnum)
+{
+  if (!d->len) return (errno = EINVAL, 0) ;
+  if (d->s[d->len - 1] == '.')
+  {
+    list[0] = *d ;
+    return 1 ;
+  }
+  else
+  {
+    register unsigned int i = 0 ;
+    for (; i < rulesnum ; i++)
+    {
+      unsigned int n = str_len(rules) ;
+      if (d->len + n >= 254) return (errno = ENAMETOOLONG, 0) ;
+      list[i] = *d ;
+      list[i].s[d->len] = '.' ;
+      byte_copy(list[i].s + d->len + 1, n, rules) ;
+      list[i].len += n+1 ;
+      rules += n+1 ;
+    }
+    return i ;
+  }
+}
diff --git a/src/libs6dns/s6dns_domain_tostring.c b/src/libs6dns/s6dns_domain_tostring.c
new file mode 100644
index 0000000..ff72893
--- /dev/null
+++ b/src/libs6dns/s6dns_domain_tostring.c
@@ -0,0 +1,21 @@
+/* ISC license. */
+
+#include <errno.h>
+#include <skalibs/bytestr.h>
+#include <s6-dns/s6dns-domain.h>
+
+unsigned int s6dns_domain_tostring (char *s, unsigned int max, s6dns_domain_t const *d)
+{
+  if ((unsigned int)d->len + 1 > max) return (errno = ENAMETOOLONG, 0) ;
+  if (!d->len || (d->s[0] != '.')) return (errno = EINVAL, 0) ;
+  if (d->len == 1)
+  {
+    s[0] = '.' ;
+    return 1 ;
+  }
+  else
+  {
+    byte_copy(s, d->len - 1, d->s + 1) ;
+    return d->len - 1 ;
+  }
+}
diff --git a/src/libs6dns/s6dns_engine.c b/src/libs6dns/s6dns_engine.c
new file mode 100644
index 0000000..4145ef7
--- /dev/null
+++ b/src/libs6dns/s6dns_engine.c
@@ -0,0 +1,372 @@
+/* ISC license. */
+
+#include <errno.h>
+#include <skalibs/uint16.h>
+#include <skalibs/uint32.h>
+#include <skalibs/allreadwrite.h>
+#include <skalibs/bytestr.h>
+#include <skalibs/error.h>
+#include <skalibs/tai.h>
+#include <skalibs/stralloc.h>
+#include <skalibs/mininetstring.h>
+#include <skalibs/socket.h>
+#include <skalibs/djbunix.h>
+#include <skalibs/ip46.h>
+#include <skalibs/random.h>
+#include <s6-dns/s6dns-constants.h>
+#include <s6-dns/s6dns-message-internal.h>
+#include <s6-dns/s6dns-message.h>
+#include <s6-dns/s6dns-engine.h>
+
+
+ /* Utility functions */
+
+static inline int qdomain_diff (char const *s1, unsigned int n1, char const *s2, unsigned int n2)
+{
+  return (n1 < n2) ? -1 : (n1 > n2) ? 1 : case_diffb(s1, n1, s2) ;
+}
+
+static int relevant (char const *q, unsigned int qlen, char const *ans, unsigned int anslen, int strict)
+{
+  {
+    s6dns_message_header_t h ;
+    uint16 id ;
+    s6dns_message_header_unpack(ans, &h) ;
+    if (!h.qr || h.opcode || h.z || (h.counts.qd != 1)) return 0 ;
+    if (h.rd != (q[2] & 1)) return 0 ;
+    if (strict && !h.aa && !(q[2] & 1)) return 0 ;
+    uint16_unpack_big(q, &id) ;
+    if (id != h.id) return 0 ;
+  }
+  {
+    char buf[255] ;
+    unsigned int pos = 12 ;
+    unsigned int n = s6dns_message_get_domain_internal(buf, 255, ans, anslen, &pos) ;
+    if (!n) return -1 ;
+    if (pos + 4 > anslen) return (errno = EPROTO, -1) ;
+    if (qdomain_diff(buf, n, q + 12, qlen - 16)) return 0 ;
+    if (byte_diff(q + qlen - 4, 4, ans + pos)) return 0 ;
+  }
+  return 1 ;
+}
+
+
+ /* Network core functions: transport-dependent */
+
+#ifdef SKALIBS_IPV6_ENABLED
+# define socketbind46(fd, ip, port, flag) ((flag) ? socket_bind6(fd, ip, port) : socket_bind4(fd, ip, port))
+# define socketudp46(flag) ((flag) ? socket_udp6() : socket_udp4())
+# define sockettcp46(flag) ((flag) ? socket_tcp6() : socket_tcp4())
+# define socketconnect46(fd, ip, port, flag) ((flag) ? socket_connect6(fd, ip, port) : socket_connect4(fd, ip, port))
+# define S6DNS_ENGINE_LOCAL0 IP6_ANY
+#else
+# define socketbind46(fd, ip, port, flag) ((void)(flag), socket_bind4(fd, ip, port))
+# define socketudp46(flag) socket_udp4()
+# define sockettcp46(flag) socket_tcp4()
+# define socketconnect46(fd, ip, port, flag) socket_connect4(fd, ip, port)
+# define S6DNS_ENGINE_LOCAL0 "\0\0\0"
+#endif
+ 
+static int randombind (int fd, int flag)
+{
+  register unsigned int i = 0 ;
+  for (; i < 10 ; i++)
+    if (socketbind46(fd, S6DNS_ENGINE_LOCAL0, 1025 + badrandom_int(64510), flag) >= 0) return 1 ;
+  return (socketbind46(fd, S6DNS_ENGINE_LOCAL0, 0, flag) >= 0) ;
+}
+
+static int thisudp (s6dns_engine_t *dt, tain_t const *stamp)
+{
+  for (;; dt->curserver++)
+  {
+    if (dt->curserver >= S6DNS_MAX_SERVERS)
+    {
+      dt->curserver = 0 ;
+      if (++dt->protostate >= 4) return -1 ;
+    }
+    if (byte_diff(s6dns_ip46list_ip(&dt->servers, dt->curserver), SKALIBS_IP_SIZE, S6DNS_ENGINE_LOCAL0)) break ;
+  }
+  if (badrandom_string(dt->sa.s + 2, 2) < 2) return 0 ; /* random query id */
+  dt->fd = socketudp46(s6dns_ip46list_is6(&dt->servers, dt->curserver)) ;
+  if (dt->fd < 0) return 0 ;
+  if (!randombind(dt->fd, s6dns_ip46list_is6(&dt->servers, dt->curserver))) goto err ; /* random source port */
+  if ((socketconnect46(dt->fd, s6dns_ip46list_ip(&dt->servers, dt->curserver), 53, s6dns_ip46list_is6(&dt->servers, dt->curserver)) < 0)
+   && (errno != EINPROGRESS)) goto err ;
+  tain_add(&dt->localdeadline, stamp, &tain_infinite_relative) ;
+  dt->flagreading = 0 ;
+  dt->flagwriting = 1 ;
+  if (dt->debughook && dt->debughook->pre_send) (*dt->debughook->pre_send)(dt, dt->debughook->external) ;
+  return 1 ;
+ err:
+  {
+    register int e = errno ;
+    fd_close(dt->fd) ; dt->fd = -1 ;
+    errno = e ;
+  }
+  return 0 ;
+}
+
+static int thistcp (s6dns_engine_t *dt, tain_t const *stamp)
+{
+  for (; dt->curserver < S6DNS_MAX_SERVERS ; dt->curserver++)
+    if (byte_diff(s6dns_ip46list_ip(&dt->servers, dt->curserver), SKALIBS_IP_SIZE, S6DNS_ENGINE_LOCAL0)) break ;
+  if (dt->curserver >= S6DNS_MAX_SERVERS) return -1 ;
+  if (badrandom_string(dt->sa.s + 2, 2) < 2) return 0 ; /* random query id */
+  dt->fd = sockettcp46(s6dns_ip46list_is6(&dt->servers, dt->curserver)) ;
+  if (dt->fd < 0) return 0 ;
+  if (!randombind(dt->fd, s6dns_ip46list_is6(&dt->servers, dt->curserver))) goto err ; /* random source port */
+  if ((socketconnect46(dt->fd, s6dns_ip46list_ip(&dt->servers, dt->curserver), 53, s6dns_ip46list_is6(&dt->servers, dt->curserver)) < 0)
+   && (errno != EINPROGRESS)) goto err ;
+  tain_addsec(&dt->localdeadline, stamp, 10) ;
+  dt->protostate = 0 ;
+  dt->flagtcp = dt->flagconnecting = dt->flagwriting = 1 ;
+  dt->flagreading = 0 ;
+  if (dt->debughook && dt->debughook->pre_send) (*dt->debughook->pre_send)(dt, dt->debughook->external) ;
+  return 1 ;
+ err:
+  {
+    register int e = errno ;
+    fd_close(dt->fd) ; dt->fd = -1 ;
+    errno = e ;
+  }
+  return 0 ;
+}
+
+
+ /* all the rest is transport-agnostic */
+
+static int s6dns_engine_prepare (s6dns_engine_t *dt, tain_t const *stamp, int istcp)
+{
+  for (;; dt->curserver++)
+    switch (istcp ? thistcp(dt, stamp) : thisudp(dt, stamp))
+    {
+      case -1 : return (errno = ENETUNREACH, 0) ;
+      case 0 : break ;
+      case 1 : return 1 ;
+      default : return (errno = EDOM, 0) ; /* can't happen */
+    }
+}
+
+static void prepare_next (s6dns_engine_t *dt, tain_t const *stamp, int istcp)
+{
+  if (!error_isagain(errno))
+  {
+    fd_close(dt->fd) ;
+    dt->curserver++ ;
+    if (s6dns_engine_prepare(dt, stamp, istcp)) errno = EAGAIN ;
+  }
+}
+
+static int s6dns_engine_write_udp (s6dns_engine_t *dt, tain_t const *stamp)
+{
+  static unsigned int const s6dns_engine_udp_timeouts[4] = { 1, 3, 11, 45 } ;
+  if (fd_send(dt->fd, dt->sa.s + 2, dt->querylen - 2, 0) < (int)(dt->querylen - 2))
+    return (prepare_next(dt, stamp, 0), 0) ;
+  tain_addsec(&dt->localdeadline, stamp, s6dns_engine_udp_timeouts[dt->protostate]) ;
+  dt->flagwriting = 0 ;
+  dt->flagreading = 1 ;
+  if (dt->debughook && dt->debughook->post_send) (*dt->debughook->post_send)(dt, dt->debughook->external) ;
+  return (errno = EAGAIN, 1) ;
+}
+
+static int s6dns_engine_write_tcp (s6dns_engine_t *dt, tain_t const *stamp)
+{
+  unsigned int r ;
+  r = allwrite(dt->fd, dt->sa.s + dt->protostate, dt->querylen - dt->protostate) ;
+  dt->protostate += r ;
+  if (r) dt->flagconnecting = 0 ;
+  if (dt->protostate < dt->sa.len)
+  {
+    if ((errno == ECONNRESET) && dt->flagconnecting) errno = EAGAIN ;
+    prepare_next(dt, stamp, 1) ;
+    return 0 ;
+  }
+  dt->protostate = 0 ;
+  tain_addsec(&dt->localdeadline, stamp, 10) ;
+  dt->flagwriting = 0 ;
+  dt->flagreading = 1 ;
+  if (dt->debughook && dt->debughook->post_send) (*dt->debughook->post_send)(dt, dt->debughook->external) ;
+  return (errno = EAGAIN, 1) ;
+}
+
+static int s6dns_engine_read_udp (s6dns_engine_t *dt, tain_t const *stamp)
+{
+  s6dns_message_header_t h ;
+  char buf[513] ;
+  register int r = fd_recv(dt->fd, buf, 513, 0) ;
+  if (r < 0) return (prepare_next(dt, stamp, 0), 0) ;
+  if ((r > 512) || (r < 12)) return (errno = EAGAIN, 0) ;
+  switch (relevant(dt->sa.s + 2, dt->querylen - 2, buf, r, dt->flagstrict))
+  {
+    case -1 : if (!dt->flagstrict) prepare_next(dt, stamp, 0) ; return 0 ;
+    case 0 : return (errno = EAGAIN, 0) ;
+    case 1 : break ;
+    default : return (errno = EDOM, 0) ; /* can't happen */
+  }
+  if (dt->debughook && dt->debughook->post_recv)
+  {
+    if (!stralloc_catb(&dt->sa, buf, r)) return 0 ;
+    (*dt->debughook->post_recv)(dt, dt->debughook->external) ;
+    dt->sa.len = dt->querylen ;
+  }
+  s6dns_message_header_unpack(buf, &h) ;
+  if (h.tc)
+  {
+    fd_close(dt->fd) ;
+    dt->curserver = 0 ;
+    dt->protostate = 0 ;
+    if (s6dns_engine_prepare(dt, stamp, 1)) errno = EAGAIN ;
+    return 0 ;
+  }
+  switch (h.rcode)
+  {
+    case 0 : case 3 : break ; /* normal operation */
+    case 1 : case 4 : case 5 :
+      byte_zero(s6dns_ip46list_ip(&dt->servers, dt->curserver), SKALIBS_IP_SIZE) ; /* do not query it again */
+    default : prepare_next(dt, stamp, 0) ; return 0 ;
+  }
+  if (!stralloc_copyb(&dt->sa, buf, r))
+  {
+    register int e = errno ;
+    fd_close(dt->fd) ; dt->fd = -1 ;
+    errno = e ;
+    return 0 ;
+  }
+  dt->querylen = 0 ;
+  fd_close(dt->fd) ; dt->fd = -1 ;
+  dt->flagreading = 0 ;
+  return 1 ;
+}
+
+static int s6dns_engine_read_tcp (s6dns_engine_t *dt, tain_t const *stamp)
+{
+  register int r = sanitize_read(mininetstring_read(dt->fd, &dt->sa, &dt->protostate)) ;
+  if (r < 0) return (prepare_next(dt, stamp, 1), 0) ;
+  else if (!r) return (errno = EAGAIN, 0) ;
+  else if ((dt->sa.len - dt->querylen) < 12)
+  {
+    errno = EPROTO ;
+    goto badanswer ;
+  }
+  else
+  {
+    s6dns_message_header_t h ;
+    switch (relevant(dt->sa.s + 2, dt->querylen - 2, dt->sa.s + dt->querylen, dt->sa.len - dt->querylen, dt->flagstrict))
+    {
+      case -1 : if (dt->flagstrict) { dt->sa.len = dt->querylen ; return 0 ; }
+      case 0 : goto badanswer ;
+      case 1 : break ;
+      default : dt->sa.len = dt->querylen ; return (errno = EDOM, 0) ; /* can't happen */
+    }
+    if (dt->debughook && dt->debughook->post_recv) (*dt->debughook->post_recv)(dt, dt->debughook->external) ;
+    s6dns_message_header_unpack(dt->sa.s + dt->querylen, &h) ;
+    if (h.tc) goto badanswer ;
+    switch (h.rcode)
+    {
+      case 0 : case 3 : break ; /* normal operation */
+      case 1 : case 4 : case 5 :
+        byte_zero(s6dns_ip46list_ip(&dt->servers, dt->curserver), SKALIBS_IP_SIZE) ; /* do not query it again */
+      default : goto badanswer ;
+    }
+    fd_close(dt->fd) ; dt->fd = -1 ;
+    dt->flagreading = 0 ;
+    return 1 ;
+  }
+ badanswer:
+  dt->sa.len = dt->querylen ;
+  prepare_next(dt, stamp, 1) ;
+  return 0 ;
+}
+
+
+void s6dns_engine_recycle (s6dns_engine_t *dt)
+{
+  dt->sa.len = 0 ;
+  dt->querylen = 0 ;
+  byte_zero(&dt->servers, sizeof(s6dns_ip46list_t)) ;
+  if (dt->fd >= 0)
+  {
+    register int e = errno ;
+    fd_close(dt->fd) ;
+    dt->fd = -1 ;
+    errno = e ;
+  }
+  dt->status = ECONNABORTED ;
+  dt->flagstrict = dt->flagtcp = dt->flagconnecting = dt->flagreading = dt->flagwriting = 0 ;
+}
+
+int s6dns_engine_timeout (s6dns_engine_t *dt, tain_t const *stamp)
+{
+  if (!error_isagain(dt->status)) return (errno = EINVAL, -1) ;
+  else if (tain_less(&dt->deadline, stamp)) goto yes ;
+  else if (!tain_less(&dt->localdeadline, stamp)) return 0 ;
+  else if (dt->flagwriting) goto yes ;
+  else if (!dt->flagreading) return 0 ;
+  fd_close(dt->fd) ;
+  dt->curserver++ ;
+  if (!s6dns_engine_prepare(dt, stamp, dt->flagtcp))
+  {
+    s6dns_engine_recycle(dt) ;
+    dt->status = errno ;
+    return -1 ;
+  }
+  return 0 ;
+ yes:
+  s6dns_engine_recycle(dt) ;
+  dt->status = ETIMEDOUT ;
+  return 1 ;
+}
+
+int s6dns_engine_event (s6dns_engine_t *dt, tain_t const *stamp)
+{
+  if (!error_isagain(dt->status)) return (errno = EINVAL, -1) ;
+  if (dt->flagwriting)
+    dt->flagtcp ? s6dns_engine_write_tcp(dt, stamp) : s6dns_engine_write_udp(dt, stamp) ;
+  else if (dt->flagreading)
+  {
+    if ((dt->flagtcp) ? s6dns_engine_read_tcp(dt, stamp) : s6dns_engine_read_udp(dt, stamp))
+    {
+      dt->status = 0 ;
+      return 1 ;
+    }
+  }
+  else return (errno = EINVAL, -1) ;
+  if (error_isagain(errno)) return 0 ;
+  s6dns_engine_recycle(dt) ;
+  dt->status = errno ;
+  return -1 ;
+}
+
+int s6dns_engine_init_r (s6dns_engine_t *dt, s6dns_ip46list_t const *servers, uint32 options, char const *q, unsigned int qlen, uint16 qtype, s6dns_debughook_t const *dbh, tain_t const *deadline, tain_t const *stamp)
+{
+  s6dns_message_header_t h = S6DNS_MESSAGE_HEADER_ZERO ;
+  if (!stralloc_ready(&dt->sa, qlen + 18)) return 0 ;
+  dt->deadline = *deadline ;
+  dt->localdeadline = *stamp ;
+  dt->querylen = qlen + 18 ;
+  dt->sa.len = dt->querylen ;
+  dt->servers = *servers ;
+  dt->debughook = dbh ;
+  dt->status = EAGAIN ;
+  dt->flagconnecting = dt->flagreading = dt->flagwriting = 0 ;
+  dt->flagstrict = !!(options & S6DNS_O_STRICT) ;
+  h.rd = !!(options & S6DNS_O_RECURSIVE) ;
+  h.counts.qd = 1 ;
+  uint16_pack_big(dt->sa.s, qlen + 16) ;
+  s6dns_message_header_pack(dt->sa.s + 2, &h) ;
+  byte_copy(dt->sa.s + 14, qlen, q) ;
+  uint16_pack_big(dt->sa.s + 14 + qlen, qtype) ;
+  uint16_pack_big(dt->sa.s + 16 + qlen, S6DNS_C_IN) ;
+  if (qlen > 496) dt->flagtcp = 1 ;
+  else
+  {
+    dt->flagtcp = 0 ;
+    dt->protostate = h.rd ;
+  }
+  if (!s6dns_engine_prepare(dt, stamp, dt->flagtcp))
+  {
+    s6dns_engine_recycle(dt) ;
+    return 0 ;
+  }
+  return 1 ;
+}
diff --git a/src/libs6dns/s6dns_engine_free.c b/src/libs6dns/s6dns_engine_free.c
new file mode 100644
index 0000000..cfee465
--- /dev/null
+++ b/src/libs6dns/s6dns_engine_free.c
@@ -0,0 +1,11 @@
+/* ISC license. */
+
+#include <skalibs/stralloc.h>
+#include <s6-dns/s6dns-engine.h>
+
+void s6dns_engine_free (s6dns_engine_t *dt)
+{
+  s6dns_engine_recycle(dt) ;
+  stralloc_free(&dt->sa) ;
+  *dt = s6dns_engine_zero ;
+}
diff --git a/src/libs6dns/s6dns_engine_freen.c b/src/libs6dns/s6dns_engine_freen.c
new file mode 100644
index 0000000..10dd47e
--- /dev/null
+++ b/src/libs6dns/s6dns_engine_freen.c
@@ -0,0 +1,8 @@
+/* ISC license. */
+
+#include <s6-dns/s6dns-engine.h>
+
+void s6dns_engine_freen (s6dns_engine_t *dtl, unsigned int n)
+{
+  while (n--) s6dns_engine_free(dtl + n) ;
+}
diff --git a/src/libs6dns/s6dns_engine_here.c b/src/libs6dns/s6dns_engine_here.c
new file mode 100644
index 0000000..17a5f43
--- /dev/null
+++ b/src/libs6dns/s6dns_engine_here.c
@@ -0,0 +1,7 @@
+/* ISC license. */
+
+/* MT-unsafe */
+
+#include <s6-dns/s6dns-engine.h>
+
+s6dns_engine_t s6dns_engine_here = S6DNS_ENGINE_ZERO ;
diff --git a/src/libs6dns/s6dns_engine_nextdeadline.c b/src/libs6dns/s6dns_engine_nextdeadline.c
new file mode 100644
index 0000000..09102c7
--- /dev/null
+++ b/src/libs6dns/s6dns_engine_nextdeadline.c
@@ -0,0 +1,10 @@
+/* ISC license. */
+
+#include <skalibs/tai.h>
+#include <s6-dns/s6dns-engine.h>
+
+void s6dns_engine_nextdeadline (s6dns_engine_t const *dt, tain_t *deadline)
+{
+  if (tain_less(&dt->deadline, deadline)) *deadline = dt->deadline ;
+  if (tain_less(&dt->localdeadline, deadline)) *deadline = dt->localdeadline ;
+}
diff --git a/src/libs6dns/s6dns_engine_zero.c b/src/libs6dns/s6dns_engine_zero.c
new file mode 100644
index 0000000..ef3acaf
--- /dev/null
+++ b/src/libs6dns/s6dns_engine_zero.c
@@ -0,0 +1,5 @@
+/* ISC license. */
+
+#include <s6-dns/s6dns-engine.h>
+
+s6dns_engine_t const s6dns_engine_zero = S6DNS_ENGINE_ZERO ;
diff --git a/src/libs6dns/s6dns_fmt_domainlist.c b/src/libs6dns/s6dns_fmt_domainlist.c
new file mode 100644
index 0000000..d53050a
--- /dev/null
+++ b/src/libs6dns/s6dns_fmt_domainlist.c
@@ -0,0 +1,25 @@
+/* ISC license. */
+
+#include <errno.h>
+#include <skalibs/bytestr.h>
+#include <s6-dns/s6dns-domain.h>
+#include <s6-dns/s6dns-fmt.h>
+
+unsigned int s6dns_fmt_domainlist (char *s, unsigned int max, s6dns_domain_t const *list, unsigned int n, char const *delim, unsigned int delimlen)
+{
+  unsigned int len = 0 ;
+  register unsigned int i = 0 ;
+  for (; i < n ; i++)
+  {
+    register unsigned int r = s6dns_domain_tostring(s + len, max - len, list + i) ;
+    if (!r) return 0 ;
+    len += r ;
+    if (i+1 < n)
+    {
+      if (len + delimlen > max) return (errno = ENAMETOOLONG, 0) ;
+      byte_copy(s + len, delimlen, delim) ;
+      len += delimlen ;
+    }
+  }
+  return len ;
+}
diff --git a/src/libs6dns/s6dns_fmt_hinfo.c b/src/libs6dns/s6dns_fmt_hinfo.c
new file mode 100644
index 0000000..8c1d7c4
--- /dev/null
+++ b/src/libs6dns/s6dns_fmt_hinfo.c
@@ -0,0 +1,15 @@
+/* ISC license. */
+
+#include <errno.h>
+#include <skalibs/bytestr.h>
+#include <s6-dns/s6dns-message.h>
+#include <s6-dns/s6dns-fmt.h>
+
+unsigned int s6dns_fmt_hinfo (char *s, unsigned int max, s6dns_message_rr_hinfo_t const *hinfo)
+{
+  if ((unsigned int)hinfo->cpu.len + 1 + (unsigned int)hinfo->os.len > max) return (errno = ENAMETOOLONG, 0) ;
+  byte_copy(s, hinfo->cpu.len, hinfo->cpu.s) ;
+  s[hinfo->cpu.len] = ' ' ;
+  byte_copy(s + hinfo->cpu.len + 1, hinfo->os.len, hinfo->os.s) ;
+  return hinfo->cpu.len + 1 + hinfo->os.len ;
+}
diff --git a/src/libs6dns/s6dns_fmt_mx.c b/src/libs6dns/s6dns_fmt_mx.c
new file mode 100644
index 0000000..aba538b
--- /dev/null
+++ b/src/libs6dns/s6dns_fmt_mx.c
@@ -0,0 +1,19 @@
+/* ISC license. */
+
+#include <skalibs/uint16.h>
+#include <skalibs/bytestr.h>
+#include <s6-dns/s6dns-message.h>
+#include <s6-dns/s6dns-fmt.h>
+
+unsigned int s6dns_fmt_mx (char *s, unsigned int max, s6dns_message_rr_mx_t const *mx)
+{
+  char fmt[UINT16_FMT] ;
+  unsigned int len = uint16_fmt(fmt, mx->preference) ;
+  unsigned int r ;
+  if (len >= max) return 0 ;
+  fmt[len++] = ' ' ;
+  r = s6dns_domain_tostring(s + len, max - len, &mx->exchange) ;
+  if (!r) return 0 ;
+  byte_copy(s, len, fmt) ;
+  return len + r ;
+}
diff --git a/src/libs6dns/s6dns_fmt_soa.c b/src/libs6dns/s6dns_fmt_soa.c
new file mode 100644
index 0000000..e066c6a
--- /dev/null
+++ b/src/libs6dns/s6dns_fmt_soa.c
@@ -0,0 +1,44 @@
+/* ISC license. */
+
+#include <errno.h>
+#include <skalibs/uint32.h>
+#include <skalibs/bytestr.h>
+#include <s6-dns/s6dns-message.h>
+#include <s6-dns/s6dns-fmt.h>
+
+unsigned int s6dns_fmt_soa (char *s, unsigned int max, s6dns_message_rr_soa_t const *soa)
+{
+  char fmt[UINT32_FMT] ;
+  unsigned int len = 0 ;
+  register unsigned int r = s6dns_domain_tostring(s + len, max - len, &soa->mname) ;
+  if (!r) return 0 ;
+  len += r ;
+  if (len >= max) return (errno = ENAMETOOLONG, 0) ;
+  s[len++] = ' ' ;
+  r = s6dns_domain_tostring(s + len, max - len, &soa->rname) ;
+  if (!r) return 0 ;
+  len += r ;
+  if (len >= max) return (errno = ENAMETOOLONG, 0) ;
+  s[len++] = ' ' ;
+  r = uint32_fmt(fmt, soa->serial) ;
+  if (len + r >= max) return (errno = ENAMETOOLONG, 0) ;
+  byte_copy(s + len, r, fmt) ;
+  len += r ; s[len++] = ' ' ;
+  r = uint32_fmt(fmt, soa->refresh) ;
+  if (len + r >= max) return (errno = ENAMETOOLONG, 0) ;
+  byte_copy(s + len, r, fmt) ;
+  len += r ; s[len++] = ' ' ;
+  r = uint32_fmt(fmt, soa->retry) ;
+  if (len + r >= max) return (errno = ENAMETOOLONG, 0) ;
+  byte_copy(s + len, r, fmt) ;
+  len += r ; s[len++] = ' ' ;
+  r = uint32_fmt(fmt, soa->expire) ;
+  if (len + r >= max) return (errno = ENAMETOOLONG, 0) ;
+  byte_copy(s + len, r, fmt) ;
+  len += r ; s[len++] = ' ' ;
+  r = uint32_fmt(fmt, soa->minimum) ;
+  if (len + r > max) return (errno = ENAMETOOLONG, 0) ;
+  byte_copy(s + len, r, fmt) ;
+  len += r ;
+  return len ;
+}
diff --git a/src/libs6dns/s6dns_fmt_srv.c b/src/libs6dns/s6dns_fmt_srv.c
new file mode 100644
index 0000000..ad0944b
--- /dev/null
+++ b/src/libs6dns/s6dns_fmt_srv.c
@@ -0,0 +1,29 @@
+/* ISC license. */
+
+#include <errno.h>
+#include <skalibs/uint16.h>
+#include <skalibs/bytestr.h>
+#include <s6-dns/s6dns-message.h>
+#include <s6-dns/s6dns-fmt.h>
+
+unsigned int s6dns_fmt_srv (char *s, unsigned int max, s6dns_message_rr_srv_t const *srv)
+{
+  char fmt[UINT16_FMT] ;
+  unsigned int len = 0 ;
+  register unsigned int r = uint16_fmt(fmt, srv->priority) ;
+  if (len + r >= max) return (errno = ENAMETOOLONG, 0) ;
+  byte_copy(s + len, r, fmt) ;
+  len += r ; s[len++] = ' ' ;
+  r = uint16_fmt(fmt, srv->weight) ;
+  if (len + r >= max) return (errno = ENAMETOOLONG, 0) ;
+  byte_copy(s + len, r, fmt) ;
+  len += r ; s[len++] = ' ' ;
+  r = uint16_fmt(fmt, srv->port) ;
+  if (len + r >= max) return (errno = ENAMETOOLONG, 0) ;
+  byte_copy(s + len, r, fmt) ;
+  len += r ; s[len++] = ' ' ;
+  r = s6dns_domain_tostring(s + len, max - len, &srv->target) ;
+  if (!r) return 0 ;
+  len += r ;
+  return len ;
+}
diff --git a/src/libs6dns/s6dns_message_counts_next.c b/src/libs6dns/s6dns_message_counts_next.c
new file mode 100644
index 0000000..2006775
--- /dev/null
+++ b/src/libs6dns/s6dns_message_counts_next.c
@@ -0,0 +1,12 @@
+/* ISC license. */
+
+#include <s6-dns/s6dns-message.h>
+
+unsigned int s6dns_message_counts_next (s6dns_message_counts_t *counts)
+{
+  if (counts->qd) { counts->qd-- ; return 1 ; }
+  else if (counts->an) { counts->an-- ; return 2 ; }
+  else if (counts->ns) { counts->ns-- ; return 3 ; }
+  else if (counts->nr) { counts->nr-- ; return 4 ; }
+  else return 0 ;
+}
diff --git a/src/libs6dns/s6dns_message_counts_pack.c b/src/libs6dns/s6dns_message_counts_pack.c
new file mode 100644
index 0000000..51c0a78
--- /dev/null
+++ b/src/libs6dns/s6dns_message_counts_pack.c
@@ -0,0 +1,12 @@
+/* ISC license. */
+
+#include <skalibs/uint16.h>
+#include <s6-dns/s6dns-message.h>
+
+void s6dns_message_counts_pack (char *s, s6dns_message_counts_t const *counts)
+{
+  uint16_pack_big(s, counts->qd) ;
+  uint16_pack_big(s+2, counts->an) ;
+  uint16_pack_big(s+4, counts->ns) ;
+  uint16_pack_big(s+6, counts->nr) ;
+}
diff --git a/src/libs6dns/s6dns_message_counts_unpack.c b/src/libs6dns/s6dns_message_counts_unpack.c
new file mode 100644
index 0000000..968e5eb
--- /dev/null
+++ b/src/libs6dns/s6dns_message_counts_unpack.c
@@ -0,0 +1,12 @@
+/* ISC license. */
+
+#include <skalibs/uint16.h>
+#include <s6-dns/s6dns-message.h>
+
+void s6dns_message_counts_unpack (char const *s, s6dns_message_counts_t *counts)
+{
+  uint16_unpack_big(s, &counts->qd) ;
+  uint16_unpack_big(s+2, &counts->an) ;
+  uint16_unpack_big(s+4, &counts->ns) ;
+  uint16_unpack_big(s+6, &counts->nr) ;
+}
diff --git a/src/libs6dns/s6dns_message_counts_zero.c b/src/libs6dns/s6dns_message_counts_zero.c
new file mode 100644
index 0000000..b177aad
--- /dev/null
+++ b/src/libs6dns/s6dns_message_counts_zero.c
@@ -0,0 +1,5 @@
+/* ISC license. */
+
+#include <s6-dns/s6dns-message.h>
+
+s6dns_message_counts_t const s6dns_message_counts_zero = S6DNS_MESSAGE_COUNTS_ZERO ;
diff --git a/src/libs6dns/s6dns_message_get_domain.c b/src/libs6dns/s6dns_message_get_domain.c
new file mode 100644
index 0000000..b51adb5
--- /dev/null
+++ b/src/libs6dns/s6dns_message_get_domain.c
@@ -0,0 +1,11 @@
+/* ISC license. */
+
+#include <s6-dns/s6dns-domain.h>
+#include <s6-dns/s6dns-message-internal.h>
+#include <s6-dns/s6dns-message.h>
+
+int s6dns_message_get_domain (s6dns_domain_t *d, char const *packet, unsigned int packetlen, unsigned int *pos)
+{
+  return s6dns_message_get_domain_internal(d->s, 255, packet, packetlen, pos)
+      && s6dns_domain_decode(d) ;
+}
diff --git a/src/libs6dns/s6dns_message_get_domain_internal.c b/src/libs6dns/s6dns_message_get_domain_internal.c
new file mode 100644
index 0000000..357797d
--- /dev/null
+++ b/src/libs6dns/s6dns_message_get_domain_internal.c
@@ -0,0 +1,47 @@
+/* ISC license. */
+
+#include <errno.h>
+#include <skalibs/error.h>
+#include <skalibs/bytestr.h>
+#include "s6dns-message-internal.h"
+
+unsigned int s6dns_message_get_domain_internal (char *out, unsigned int outmax, char const *s, unsigned int len, unsigned int *pos)
+{
+  unsigned int w = 0 ; /* writing head */
+  unsigned int r = *pos ; /* reading head */
+  unsigned int jumps = 0 ;
+  register int hasjumped = 0 ;
+  for (;;)
+  {
+    unsigned char c ;
+    if (r >= len) return (errno = EPROTO, 0) ;
+    c = s[r] ;
+    if (c < 64) /* normal label */
+    {
+      if (r + ++c > len) return (errno = EPROTO, 0) ;
+      if (out)
+      {
+        if (w + c > outmax) return (errno = ENAMETOOLONG, 0) ;
+        byte_copy(out + w, c, s + r) ;
+      }
+      w += c ; r += c ; if (!hasjumped) *pos += c ;
+      if (c == 1) break ;
+    }
+    else if (c >= 192) /* pointer */
+    {
+      if (r + 1 >= len) return (errno = EPROTO, 0) ;
+      if (hasjumped)
+      {
+        if (++jumps > 1000) return (errno = EPROTO, 0) ;
+      }
+      else
+      {
+        *pos += 2 ;
+        hasjumped = 1 ;
+      }
+      r = (((unsigned int)c & 63) << 8) | (unsigned char)(s[r + 1]) ;
+    }
+    else return (errno = EPROTONOSUPPORT, 0) ; /* unsupported extension */
+  }
+  return w ;
+}
diff --git a/src/libs6dns/s6dns_message_get_hinfo.c b/src/libs6dns/s6dns_message_get_hinfo.c
new file mode 100644
index 0000000..c8ab821
--- /dev/null
+++ b/src/libs6dns/s6dns_message_get_hinfo.c
@@ -0,0 +1,9 @@
+/* ISC license. */
+
+#include <s6-dns/s6dns-message.h>
+
+int s6dns_message_get_hinfo (s6dns_message_rr_hinfo_t_ref hinfo, char const *packet, unsigned int packetlen, unsigned int *pos)
+{
+  return s6dns_message_get_string(&hinfo->cpu, packet, packetlen, pos)
+   && s6dns_message_get_string(&hinfo->os, packet, packetlen, pos) ;
+}
diff --git a/src/libs6dns/s6dns_message_get_mx.c b/src/libs6dns/s6dns_message_get_mx.c
new file mode 100644
index 0000000..6bca509
--- /dev/null
+++ b/src/libs6dns/s6dns_message_get_mx.c
@@ -0,0 +1,14 @@
+/* ISC license. */
+
+#include <errno.h>
+#include <skalibs/error.h>
+#include <skalibs/uint16.h>
+#include <s6-dns/s6dns-domain.h>
+#include <s6-dns/s6dns-message.h>
+
+int s6dns_message_get_mx (s6dns_message_rr_mx_t *mx, char const *packet, unsigned int packetlen, unsigned int *pos)
+{
+  if (*pos + 3 > packetlen) return (errno = EPROTO, 0) ;
+  uint16_unpack_big(packet + *pos, &mx->preference) ; *pos += 2 ;
+  return s6dns_message_get_domain(&mx->exchange, packet, packetlen, pos) ;
+}
diff --git a/src/libs6dns/s6dns_message_get_soa.c b/src/libs6dns/s6dns_message_get_soa.c
new file mode 100644
index 0000000..c766231
--- /dev/null
+++ b/src/libs6dns/s6dns_message_get_soa.c
@@ -0,0 +1,19 @@
+/* ISC license. */
+
+#include <errno.h>
+#include <skalibs/error.h>
+#include <skalibs/uint32.h>
+#include <s6-dns/s6dns-message.h>
+
+int s6dns_message_get_soa (s6dns_message_rr_soa_t *soa, char const *packet, unsigned int packetlen, unsigned int *pos)
+{
+  if (!s6dns_message_get_domain(&soa->mname, packet, packetlen, pos)) return 0 ;
+  if (!s6dns_message_get_domain(&soa->rname, packet, packetlen, pos)) return 0 ;
+  if (*pos + 20 > packetlen) return (errno = EPROTO, 0) ;
+  uint32_unpack_big(packet + *pos, &soa->serial) ; *pos += 4 ;
+  uint32_unpack_big(packet + *pos, &soa->refresh) ; *pos += 4 ;
+  uint32_unpack_big(packet + *pos, &soa->retry) ; *pos += 4 ;
+  uint32_unpack_big(packet + *pos, &soa->expire) ; *pos += 4 ;
+  uint32_unpack_big(packet + *pos, &soa->minimum) ; *pos += 4 ;
+  return 1 ;
+}
diff --git a/src/libs6dns/s6dns_message_get_srv.c b/src/libs6dns/s6dns_message_get_srv.c
new file mode 100644
index 0000000..13ecf13
--- /dev/null
+++ b/src/libs6dns/s6dns_message_get_srv.c
@@ -0,0 +1,15 @@
+/* ISC license. */
+
+#include <errno.h>
+#include <skalibs/error.h>
+#include <skalibs/uint16.h>
+#include <s6-dns/s6dns-message.h>
+
+int s6dns_message_get_srv (s6dns_message_rr_srv_t *srv, char const *packet, unsigned int packetlen, unsigned int *pos)
+{
+  if (*pos + 7 > packetlen) return (errno = EPROTO, 0) ;
+  uint16_unpack_big(packet + *pos, &srv->priority) ; *pos += 2 ;
+  uint16_unpack_big(packet + *pos, &srv->weight) ; *pos += 2 ;
+  uint16_unpack_big(packet + *pos, &srv->port) ; *pos += 2 ;
+  return s6dns_message_get_domain(&srv->target, packet, packetlen, pos) ;
+}
diff --git a/src/libs6dns/s6dns_message_get_string.c b/src/libs6dns/s6dns_message_get_string.c
new file mode 100644
index 0000000..706da39
--- /dev/null
+++ b/src/libs6dns/s6dns_message_get_string.c
@@ -0,0 +1,13 @@
+/* ISC license. */
+
+#include <s6-dns/s6dns-domain.h>
+#include <s6-dns/s6dns-message.h>
+#include "s6dns-message-internal.h"
+
+int s6dns_message_get_string (s6dns_domain_t *d, char const *packet, unsigned int packetlen, unsigned int *pos)
+{
+  register int r = s6dns_message_get_string_internal(d->s, 255, packet, packetlen, pos) ;
+  if (r < 0) return 0 ;
+  d->len = r ;
+  return 1 ;
+}
diff --git a/src/libs6dns/s6dns_message_get_string_internal.c b/src/libs6dns/s6dns_message_get_string_internal.c
new file mode 100644
index 0000000..4f6eb0c
--- /dev/null
+++ b/src/libs6dns/s6dns_message_get_string_internal.c
@@ -0,0 +1,16 @@
+/* ISC license. */
+
+#include <errno.h>
+#include <skalibs/error.h>
+#include <skalibs/bytestr.h>
+#include "s6dns-message-internal.h"
+
+int s6dns_message_get_string_internal (char *s, unsigned int max, char const *packet, unsigned int packetlen, unsigned int *pos)
+{
+  register unsigned char len = ((unsigned char const *)packet)[*pos] ;
+  if (*pos + len + 1 > packetlen) return (errno = EPROTO, -1) ;
+  if (len > max) return (errno = ENAMETOOLONG, -1) ;
+  byte_copy(s, len, packet + *pos + 1) ;
+  *pos += len + 1 ;
+  return (int)len ;
+}
diff --git a/src/libs6dns/s6dns_message_get_strings.c b/src/libs6dns/s6dns_message_get_strings.c
new file mode 100644
index 0000000..161b554
--- /dev/null
+++ b/src/libs6dns/s6dns_message_get_strings.c
@@ -0,0 +1,17 @@
+/* ISC license. */
+
+#include <s6-dns/s6dns-message.h>
+#include "s6dns-message-internal.h"
+
+int s6dns_message_get_strings (char *s, unsigned int rdlength, char const *packet, unsigned int packetlen, unsigned int *pos)
+{
+  unsigned int max = rdlength, len = 0 ;
+  while (rdlength)
+  {
+    register unsigned int start = *pos ;
+    register int r = s6dns_message_get_string_internal(s + len, max - len, packet, packetlen, pos) ;
+    if (r < 0) return -1 ;
+    len += r ; rdlength -= *pos - start ;
+  }
+  return (int)len ;
+}
diff --git a/src/libs6dns/s6dns_message_header_pack.c b/src/libs6dns/s6dns_message_header_pack.c
new file mode 100644
index 0000000..99ffa8a
--- /dev/null
+++ b/src/libs6dns/s6dns_message_header_pack.c
@@ -0,0 +1,12 @@
+/* ISC license. */
+
+#include <skalibs/uint16.h>
+#include <s6-dns/s6dns-message.h>
+
+void s6dns_message_header_pack (char *s, s6dns_message_header_t const *h)
+{
+  uint16_pack_big(s, h->id) ;
+  s[2] = (h->qr << 7) | (h->opcode << 3) | (h->aa << 2) | (h->tc << 1) | h->rd ;
+  s[3] = (h->z << 4) | h->rcode ;
+  s6dns_message_counts_pack(s+4, &h->counts) ;
+}
diff --git a/src/libs6dns/s6dns_message_header_unpack.c b/src/libs6dns/s6dns_message_header_unpack.c
new file mode 100644
index 0000000..ae2b35c
--- /dev/null
+++ b/src/libs6dns/s6dns_message_header_unpack.c
@@ -0,0 +1,18 @@
+/* ISC license. */
+
+#include <skalibs/uint16.h>
+#include <s6-dns/s6dns-message.h>
+
+void s6dns_message_header_unpack (char const *s, s6dns_message_header_t *h)
+{
+  uint16_unpack_big(s, &h->id) ;
+  h->qr = s[2] & 0x8000U ? 1 : 0 ;
+  h->opcode = (s[2] >> 3) & 15 ;
+  h->aa = s[2] & 4 ? 1 : 0 ;
+  h->tc = s[2] & 2 ? 1 : 0 ;
+  h->rd = s[2] & 1 ;
+  h->ra = s[3] & 0x8000U ? 1 : 0 ;
+  h->z = (s[3] >> 4) & 7 ;
+  h->rcode = s[3] & 15 ;
+  s6dns_message_counts_unpack(s+4, &h->counts) ;
+}
diff --git a/src/libs6dns/s6dns_message_header_zero.c b/src/libs6dns/s6dns_message_header_zero.c
new file mode 100644
index 0000000..5695e34
--- /dev/null
+++ b/src/libs6dns/s6dns_message_header_zero.c
@@ -0,0 +1,5 @@
+/* ISC license. */
+
+#include <s6-dns/s6dns-message.h>
+
+s6dns_message_header_t const s6dns_message_header_zero = S6DNS_MESSAGE_HEADER_ZERO ;
diff --git a/src/libs6dns/s6dns_message_parse.c b/src/libs6dns/s6dns_message_parse.c
new file mode 100644
index 0000000..f4af437
--- /dev/null
+++ b/src/libs6dns/s6dns_message_parse.c
@@ -0,0 +1,37 @@
+/* ISC license. */
+
+#include <errno.h>
+#include <skalibs/error.h>
+#include <s6-dns/s6dns-constants.h>
+#include <s6-dns/s6dns-message.h>
+
+int s6dns_message_parse (s6dns_message_header_t *h, char const *packet, unsigned int packetlen, s6dns_message_rr_func_t_ref f, void *data)
+{
+  s6dns_message_counts_t counts ;
+  unsigned int pos ;
+  unsigned int section ;
+  if (!s6dns_message_parse_init(h, &counts, packet, packetlen, &pos)) return 0 ;
+  switch (h->rcode)
+  {
+    case 0 : break ;
+    case 1 : return (errno = EBADMSG, 0) ;
+    case 2 : return (errno = EBUSY, 0) ;
+    case 3 : return (errno = ENOENT, 0) ;
+    case 4 : return (errno = ENOTSUP, 0) ;
+    case 5 : return (errno = ECONNREFUSED, 0) ;
+    default: return (errno = EIO, 0) ;
+  }
+  section = s6dns_message_parse_skipqd(&counts, packet, packetlen, &pos) ;
+  while (section)
+  {
+    s6dns_message_rr_t rr ;
+    if (!s6dns_message_parse_getrr(&rr, packet, packetlen, &pos)) return 0 ;
+    if (rr.rclass == S6DNS_C_IN)
+    {
+      register int r = (*f)(&rr, packet, packetlen, pos, section, data) ;
+      if (r < 1) return r ;
+    }
+    section = s6dns_message_parse_next(&counts, &rr, packet, packetlen, &pos) ;
+  }
+  return 1 ;
+}
diff --git a/src/libs6dns/s6dns_message_parse_answer_a.c b/src/libs6dns/s6dns_message_parse_answer_a.c
new file mode 100644
index 0000000..152b947
--- /dev/null
+++ b/src/libs6dns/s6dns_message_parse_answer_a.c
@@ -0,0 +1,16 @@
+/* ISC license. */
+
+#include <skalibs/stralloc.h>
+#include <s6-dns/s6dns-constants.h>
+#include <s6-dns/s6dns-message.h>
+
+int s6dns_message_parse_answer_a (s6dns_message_rr_t const *rr, char const *packet, unsigned int packetlen, unsigned int pos, unsigned int section, void *stuff)
+{
+  if ((section == 2) && (rr->rtype == S6DNS_T_A) && (rr->rdlength == 4))
+  {
+    stralloc *data = stuff ;
+    if (!stralloc_catb(data, packet+pos, 4)) return -1 ;
+  }
+  (void)packetlen ;
+  return 1 ;
+}
diff --git a/src/libs6dns/s6dns_message_parse_answer_aaaa.c b/src/libs6dns/s6dns_message_parse_answer_aaaa.c
new file mode 100644
index 0000000..f1e71e5
--- /dev/null
+++ b/src/libs6dns/s6dns_message_parse_answer_aaaa.c
@@ -0,0 +1,16 @@
+/* ISC license. */
+
+#include <skalibs/stralloc.h>
+#include <s6-dns/s6dns-constants.h>
+#include <s6-dns/s6dns-message.h>
+
+int s6dns_message_parse_answer_aaaa (s6dns_message_rr_t const *rr, char const *packet, unsigned int packetlen, unsigned int pos, unsigned int section, void *stuff)
+{
+  if ((section == 2) && (rr->rtype == S6DNS_T_AAAA) && (rr->rdlength == 16))
+  {
+    stralloc *data = stuff ;
+    if (!stralloc_catb(data, packet + pos, 16)) return -1 ;
+  }
+  (void)packetlen ;
+  return 1 ;
+}
diff --git a/src/libs6dns/s6dns_message_parse_answer_domain.c b/src/libs6dns/s6dns_message_parse_answer_domain.c
new file mode 100644
index 0000000..d09abc9
--- /dev/null
+++ b/src/libs6dns/s6dns_message_parse_answer_domain.c
@@ -0,0 +1,21 @@
+/* ISC license. */
+
+#include <errno.h>
+#include <skalibs/error.h>
+#include <skalibs/genalloc.h>
+#include <s6-dns/s6dns-domain.h>
+#include <s6-dns/s6dns-message.h>
+
+int s6dns_message_parse_answer_domain (s6dns_message_rr_t const *rr, char const *packet, unsigned int packetlen, unsigned int pos, unsigned int section, void *stuff)
+{
+  s6dns_dpag_t *data = stuff ;
+  if ((section == 2) && (rr->rtype == data->rtype))
+  {
+    s6dns_domain_t d ;
+    register unsigned int start = pos ;
+    if (!s6dns_message_get_domain(&d, packet, packetlen, &pos)) return 0 ;
+    if (rr->rdlength != pos - start) return (errno = EPROTO, 0) ;
+    if (!genalloc_append(s6dns_domain_t, &data->ds, &d)) return -1 ;
+  }
+  return 1 ;
+}
diff --git a/src/libs6dns/s6dns_message_parse_answer_hinfo.c b/src/libs6dns/s6dns_message_parse_answer_hinfo.c
new file mode 100644
index 0000000..aa53601
--- /dev/null
+++ b/src/libs6dns/s6dns_message_parse_answer_hinfo.c
@@ -0,0 +1,21 @@
+/* ISC license. */
+
+#include <errno.h>
+#include <skalibs/error.h>
+#include <skalibs/genalloc.h>
+#include <s6-dns/s6dns-constants.h>
+#include <s6-dns/s6dns-message.h>
+
+int s6dns_message_parse_answer_hinfo (s6dns_message_rr_t const *rr, char const *packet, unsigned int packetlen, unsigned int pos, unsigned int section, void *stuff)
+{
+  if ((section == 2) && (rr->rtype == S6DNS_T_HINFO))
+  {
+    genalloc *data = stuff ;
+    s6dns_message_rr_hinfo_t hinfo ;
+    register unsigned int start = pos ;
+    if (!s6dns_message_get_hinfo(&hinfo, packet, packetlen, &pos)) return 0 ;
+    if (rr->rdlength != pos - start) return (errno = EPROTO, 0) ;
+    if (!genalloc_append(s6dns_message_rr_hinfo_t, data, &hinfo)) return -1 ;
+  }
+  return 1 ;
+}
diff --git a/src/libs6dns/s6dns_message_parse_answer_mx.c b/src/libs6dns/s6dns_message_parse_answer_mx.c
new file mode 100644
index 0000000..32f43c9
--- /dev/null
+++ b/src/libs6dns/s6dns_message_parse_answer_mx.c
@@ -0,0 +1,21 @@
+/* ISC license. */
+
+#include <errno.h>
+#include <skalibs/error.h>
+#include <skalibs/genalloc.h>
+#include <s6-dns/s6dns-constants.h>
+#include <s6-dns/s6dns-message.h>
+
+int s6dns_message_parse_answer_mx (s6dns_message_rr_t const *rr, char const *packet, unsigned int packetlen, unsigned int pos, unsigned int section, void *stuff)
+{
+  if ((section == 2) && (rr->rtype == S6DNS_T_MX))
+  {
+    genalloc *data = stuff ;
+    s6dns_message_rr_mx_t mx ;
+    register unsigned int start = pos ;
+    if (!s6dns_message_get_mx(&mx, packet, packetlen, &pos)) return 0 ;
+    if (rr->rdlength != pos - start) return (errno = EPROTO, 0) ;
+    if (!genalloc_append(s6dns_message_rr_mx_t, data, &mx)) return -1 ;
+  }
+  return 1 ;
+}
diff --git a/src/libs6dns/s6dns_message_parse_answer_soa.c b/src/libs6dns/s6dns_message_parse_answer_soa.c
new file mode 100644
index 0000000..6c7b668
--- /dev/null
+++ b/src/libs6dns/s6dns_message_parse_answer_soa.c
@@ -0,0 +1,21 @@
+/* ISC license. */
+
+#include <errno.h>
+#include <skalibs/error.h>
+#include <skalibs/genalloc.h>
+#include <s6-dns/s6dns-constants.h>
+#include <s6-dns/s6dns-message.h>
+
+int s6dns_message_parse_answer_soa (s6dns_message_rr_t const *rr, char const *packet, unsigned int packetlen, unsigned int pos, unsigned int section, void *stuff)
+{
+  if ((section == 2) && (rr->rtype == S6DNS_T_SOA))
+  {
+    genalloc *data = stuff ;
+    s6dns_message_rr_soa_t soa ;
+    register unsigned int start = pos ;
+    if (!s6dns_message_get_soa(&soa, packet, packetlen, &pos)) return 0 ;
+    if (rr->rdlength != pos - start) return (errno = EPROTO, 0) ;
+    if (!genalloc_append(s6dns_message_rr_soa_t, data, &soa)) return -1 ;
+  }
+  return 1 ;
+}
diff --git a/src/libs6dns/s6dns_message_parse_answer_srv.c b/src/libs6dns/s6dns_message_parse_answer_srv.c
new file mode 100644
index 0000000..31be348
--- /dev/null
+++ b/src/libs6dns/s6dns_message_parse_answer_srv.c
@@ -0,0 +1,21 @@
+/* ISC license. */
+
+#include <errno.h>
+#include <skalibs/error.h>
+#include <skalibs/genalloc.h>
+#include <s6-dns/s6dns-constants.h>
+#include <s6-dns/s6dns-message.h>
+
+int s6dns_message_parse_answer_srv (s6dns_message_rr_t const *rr, char const *packet, unsigned int packetlen, unsigned int pos, unsigned int section, void *stuff)
+{
+  if ((section == 2) && (rr->rtype == S6DNS_T_SRV))
+  {
+    genalloc *data = stuff ;
+    s6dns_message_rr_srv_t srv ;
+    register unsigned int start = pos ;
+    if (!s6dns_message_get_srv(&srv, packet, packetlen, &pos)) return 0 ;
+    if (rr->rdlength != pos - start) return (errno = EPROTO, 0) ;
+    if (!genalloc_append(s6dns_message_rr_srv_t, data, &srv)) return -1 ;
+  }
+  return 1 ;
+}
diff --git a/src/libs6dns/s6dns_message_parse_answer_strings.c b/src/libs6dns/s6dns_message_parse_answer_strings.c
new file mode 100644
index 0000000..09470c7
--- /dev/null
+++ b/src/libs6dns/s6dns_message_parse_answer_strings.c
@@ -0,0 +1,36 @@
+/* ISC license. */
+
+#include <errno.h>
+#include <skalibs/error.h>
+#include <skalibs/stralloc.h>
+#include <skalibs/genalloc.h>
+#include <s6-dns/s6dns-message.h>
+
+int s6dns_message_parse_answer_strings (s6dns_message_rr_t const *rr, char const *packet, unsigned int packetlen, unsigned int pos, unsigned int section, void *stuff)
+{
+  s6dns_mpag_t_ref data = stuff ;
+  if ((section == 2) && (rr->rtype == data->rtype))
+  {
+    unsigned int base = data->sa.len ;
+    int wasnull = !data->sa.s ;
+    unsigned int start = pos ;
+    register int r ;
+    if (!stralloc_readyplus(&data->sa, rr->rdlength + 1)) return -1 ;
+    errno = EPROTO ;
+    r = s6dns_message_get_strings(data->sa.s + data->sa.len, rr->rdlength, packet, packetlen, &pos) ;
+    if ((r < 0) || (rr->rdlength != pos - start))
+    {
+      if (wasnull) stralloc_free(&data->sa) ; else data->sa.len = base ;
+      return 0 ;
+    }
+    if (!genalloc_append(unsigned int, &data->offsets, &data->sa.len))
+    {
+      if (wasnull) stralloc_free(&data->sa) ; else data->sa.len = base ;
+      return -1 ;
+    }
+    errno = 0 ;
+    data->sa.len += r ;
+    stralloc_0(&data->sa) ;
+  }
+  return 1 ;
+}
diff --git a/src/libs6dns/s6dns_message_parse_getrr.c b/src/libs6dns/s6dns_message_parse_getrr.c
new file mode 100644
index 0000000..8db0c5d
--- /dev/null
+++ b/src/libs6dns/s6dns_message_parse_getrr.c
@@ -0,0 +1,19 @@
+/* ISC license. */
+
+#include <errno.h>
+#include <skalibs/error.h>
+#include <skalibs/uint16.h>
+#include <skalibs/uint32.h>
+#include <s6-dns/s6dns-message.h>
+
+int s6dns_message_parse_getrr (s6dns_message_rr_t_ref rr, char const *packet, unsigned int packetlen, unsigned int *pos)
+{
+  if (!s6dns_message_get_domain(&rr->name, packet, packetlen, pos)) return 0 ;
+  if (*pos + 10 > packetlen) return (errno = EPROTO, 0) ;
+  uint16_unpack_big(packet + *pos, &rr->rtype) ; *pos += 2 ;
+  uint16_unpack_big(packet + *pos, &rr->rclass) ; *pos += 2 ;
+  uint32_unpack_big(packet + *pos, &rr->ttl) ; *pos += 4 ;
+  uint16_unpack_big(packet + *pos, &rr->rdlength) ; *pos += 2 ;
+  if (*pos + rr->rdlength > packetlen) return (errno = EPROTO, 0) ;
+  return 1 ;
+}
diff --git a/src/libs6dns/s6dns_message_parse_init.c b/src/libs6dns/s6dns_message_parse_init.c
new file mode 100644
index 0000000..3b4efc5
--- /dev/null
+++ b/src/libs6dns/s6dns_message_parse_init.c
@@ -0,0 +1,13 @@
+/* ISC license. */
+
+#include <errno.h>
+#include <s6-dns/s6dns-message.h>
+
+int s6dns_message_parse_init (s6dns_message_header_t *h, s6dns_message_counts_t *counts, char const *packet, unsigned int packetlen, unsigned int *pos)
+{
+  if (packetlen < 12) return (errno = EPROTO, 0) ;
+  s6dns_message_header_unpack(packet, h) ;
+  *counts = h->counts ;
+  *pos = 12 ;
+  return 1 ;
+}
diff --git a/src/libs6dns/s6dns_message_parse_next.c b/src/libs6dns/s6dns_message_parse_next.c
new file mode 100644
index 0000000..a7bbce6
--- /dev/null
+++ b/src/libs6dns/s6dns_message_parse_next.c
@@ -0,0 +1,11 @@
+/* ISC license. */
+
+#include <errno.h>
+#include <s6-dns/s6dns-message.h>
+
+unsigned int s6dns_message_parse_next (s6dns_message_counts_t *counts, s6dns_message_rr_t const *rr, char const *packet, unsigned int packetlen, unsigned int *pos)
+{
+  *pos += rr->rdlength ;
+  (void)packet ; (void)packetlen ;
+  return s6dns_message_counts_next(counts) ;
+}
diff --git a/src/libs6dns/s6dns_message_parse_skipqd.c b/src/libs6dns/s6dns_message_parse_skipqd.c
new file mode 100644
index 0000000..9b8c222
--- /dev/null
+++ b/src/libs6dns/s6dns_message_parse_skipqd.c
@@ -0,0 +1,15 @@
+/* ISC license. */
+
+#include <s6-dns/s6dns-message.h>
+#include "s6dns-message-internal.h"
+
+unsigned int s6dns_message_parse_skipqd (s6dns_message_counts_t *counts, char const *packet, unsigned int packetlen, unsigned int *pos)
+{
+  for (;;)
+  {
+    register unsigned int r = s6dns_message_counts_next(counts) ;
+    if (r != 1) return r ;
+    if (!s6dns_message_get_domain_internal(0, 255, packet, packetlen, pos)) return 0 ;
+    *pos += 4 ;
+  }
+}
diff --git a/src/libs6dns/s6dns_rci_free.c b/src/libs6dns/s6dns_rci_free.c
new file mode 100644
index 0000000..d742ffe
--- /dev/null
+++ b/src/libs6dns/s6dns_rci_free.c
@@ -0,0 +1,10 @@
+/* ISC license. */
+
+#include <skalibs/stralloc.h>
+#include <s6-dns/s6dns-rci.h>
+
+void s6dns_rci_free (s6dns_rci_t *rci)
+{
+  stralloc_free(&rci->rules) ;
+  *rci = s6dns_rci_zero ;
+}
diff --git a/src/libs6dns/s6dns_rci_here.c b/src/libs6dns/s6dns_rci_here.c
new file mode 100644
index 0000000..2f08513
--- /dev/null
+++ b/src/libs6dns/s6dns_rci_here.c
@@ -0,0 +1,7 @@
+/* ISC license. */
+
+/* MT-unsafe */
+
+#include <s6-dns/s6dns-rci.h>
+
+s6dns_rci_t s6dns_rci_here = S6DNS_RCI_ZERO ;
diff --git a/src/libs6dns/s6dns_rci_init.c b/src/libs6dns/s6dns_rci_init.c
new file mode 100644
index 0000000..a4f3fcf
--- /dev/null
+++ b/src/libs6dns/s6dns_rci_init.c
@@ -0,0 +1,173 @@
+/* ISC license. */
+
+#include <errno.h>
+#include <skalibs/error.h>
+#include <skalibs/bytestr.h>
+#include <skalibs/bitarray.h>
+#include <skalibs/fmtscan.h>
+#include <skalibs/tai.h>
+#include <skalibs/djbunix.h>
+#include <skalibs/stralloc.h>
+#include <skalibs/ip46.h>
+#include <s6-dns/s6dns-constants.h>
+#include <s6-dns/s6dns-rci.h>
+
+static unsigned int readit (char const *file, char *buf, unsigned int max)
+{
+  register int r = openreadnclose(file, buf, max - 1) ;
+  if (r < 0)
+  {
+    if (errno != ENOENT) return 0 ;
+    else r = 0 ;
+  }
+  buf[r++] = '\n' ;
+  return (unsigned int)r ;
+}
+
+static inline int s6dns_rci_init_servers (s6dns_rci_t *rci, char const *file, char *tmp, unsigned int max, unsigned int *size)
+{
+  ip46_t tmplist[S6DNS_MAX_SERVERS] ;
+  unsigned int num = 0 ;
+  char const *x = env_get("DNSCACHEIP") ;
+  if (x) ip46_scanlist(tmplist, S6DNS_MAX_SERVERS, x, &num) ;
+  if (!num)
+  {
+    unsigned int i = 0 ;
+    *size = readit(file, tmp, max) ;
+    if (!*size) return 0 ;
+    while ((i < *size) && (num < S6DNS_MAX_SERVERS))
+    {
+      register unsigned int j = byte_chr(tmp + i, *size - i, '\n') ;
+      if ((i + j < *size) && (j > 13U) && !byte_diff("nameserver", 10, tmp + i))
+      {
+        register unsigned int k = 0 ;
+        while ((tmp[i+10+k] == ' ') || (tmp[i+10+k] == '\t')) k++ ;
+        if (k && ip46_scan(tmp+i+10+k, tmplist + num)) num++ ;
+      }
+      i += j + 1 ;
+    }
+  }
+  if (!num)
+  {
+    num = 1 ;
+    byte_copy(tmplist[0].ip, SKALIBS_IP_SIZE, S6DNS_LOCALHOST_IP) ;
+#ifdef SKALIBS_IPV6_ENABLED
+    tmplist[0].is6 = 1 ;
+#endif
+  }
+
+  {
+    register unsigned int i = 0 ;
+    byte_zero(&rci->servers, sizeof(s6dns_ip46list_t)) ;
+    for (; i < num ; i++)
+    {
+      byte_copy(rci->servers.ip + SKALIBS_IP_SIZE * i, SKALIBS_IP_SIZE, tmplist[i].ip) ;
+#ifdef SKALIBS_IPV6_ENABLED
+      if (ip46_is6(tmplist+i)) bitarray_set(rci->servers.is6, i) ;
+#endif
+    }
+  }
+  return 1 ;
+}
+
+static inline int stringrules (stralloc *rules, char const *s, unsigned int *num)
+{
+  unsigned int n = 0 ;
+  int crunching = 1 ;
+  int wasnull = !rules->s ;
+  unsigned int base = rules->len ;
+  char c = ' ' ;
+  while (c)
+  {
+    c = *s++ ;
+    if (byte_chr(" \t\n\r", 5, c) < 5)
+    {
+      if (!crunching)
+      {
+        if ((rules->s[rules->len - 1] != '.') && !stralloc_catb(rules, ".", 1)) goto err ;
+        if (!stralloc_0(rules)) goto err ;
+        n++ ;
+        crunching = 1 ;
+      }
+    }
+    else
+    {
+      if (crunching) crunching = 0 ;
+      if (!stralloc_catb(rules, &c, 1)) goto err ;
+    }
+  }
+  *num += n ;
+  return 1 ;
+
+ err:
+  if (wasnull) stralloc_free(rules) ;
+  else rules->len = base ;
+  return 0 ;
+}
+
+static inline int s6dns_rci_init_rules (s6dns_rci_t_ref rci, char const *file, char *tmp, unsigned int max, unsigned int *size)
+{
+  unsigned int num = 0 ;
+  char const *x = env_get("DNSQUALIFY") ;
+  if (x)
+  {
+    if (!stringrules(&rci->rules, x, &num)) return 0 ;
+  }
+  else
+  {
+    unsigned int i = 0 ;
+    if (!*size)
+    {
+      *size = readit(file, tmp, max) ;
+      if (!*size) return 0 ;
+    }
+    while (i < *size)
+    {
+      register unsigned int j = byte_chr(tmp + i, *size - i, '\n') ;
+      if ((i + j < *size) && (j > 8U)
+       && (!byte_diff("domain", 6, tmp + i) || !byte_diff("search", 6, tmp + i))
+       && ((tmp[i+6] == ' ') || (tmp[i+6] == '\t') || (tmp[i+6] == '\r')))
+      {
+        unsigned int k = 0 ;
+        int copying = 0 ;
+        register int notsearching = (tmp[i] != 's') ;
+        if (!stralloc_readyplus(&rci->rules, j)) return 0 ;
+        for (; 6 + k < j ; k++)
+        {
+          char c = tmp[i+7+k] ;
+          if ((c == ' ') || (c == '\t') || (c == '\r') || (c == '\n'))
+          {
+            if (copying)
+            {
+              copying = 0 ;
+              if ((tmp[i+6+k] != '.') && !stralloc_catb(&rci->rules, ".", 1)) return 0 ;
+              if (!stralloc_0(&rci->rules)) return 0 ;
+              num++ ;
+              if (notsearching) break ;
+            }
+          }
+          else
+          {
+            copying = 1 ;
+            if (!stralloc_catb(&rci->rules, &c, 1)) return 0 ;
+          }
+        }
+      }
+      i += j + 1 ;
+    }
+  }
+  if (!stralloc_0(&rci->rules)) return 0 ; /* empty rule to finish */
+  num++ ;
+  rci->rulesnum = num ;
+  stralloc_shrink(&rci->rules) ;
+  return 1 ;
+}
+
+int s6dns_rci_init (s6dns_rci_t *rci, char const *file)
+{
+  char tmp[4096] ;
+  unsigned int size = 0 ;
+  if (!s6dns_rci_init_servers(rci, file, tmp, 4096, &size)) return 0 ;
+  if (!s6dns_rci_init_rules(rci, file, tmp, 4096, &size)) return 0 ;
+  return 1 ;
+}
diff --git a/src/libs6dns/s6dns_rci_zero.c b/src/libs6dns/s6dns_rci_zero.c
new file mode 100644
index 0000000..384b42a
--- /dev/null
+++ b/src/libs6dns/s6dns_rci_zero.c
@@ -0,0 +1,7 @@
+/* ISC license. */
+
+/* MT-unsafe */
+
+#include <s6-dns/s6dns-rci.h>
+
+s6dns_rci_t const s6dns_rci_zero = S6DNS_RCI_ZERO ;
diff --git a/src/libs6dns/s6dns_resolve_core.c b/src/libs6dns/s6dns_resolve_core.c
new file mode 100644
index 0000000..0b75f07
--- /dev/null
+++ b/src/libs6dns/s6dns_resolve_core.c
@@ -0,0 +1,16 @@
+/* ISC license. */
+
+#include <errno.h>
+#include <skalibs/uint16.h>
+#include <skalibs/tai.h>
+#include <s6-dns/s6dns-constants.h>
+#include <s6-dns/s6dns-ip46.h>
+#include <s6-dns/s6dns-domain.h>
+#include <s6-dns/s6dns-engine.h>
+#include <s6-dns/s6dns-resolve.h>
+
+int s6dns_resolve_core_r (s6dns_domain_t const *d, uint16 qtype, s6dns_engine_t *dt, s6dns_ip46list_t const *servers, s6dns_debughook_t const *dbh, tain_t const *deadline, tain_t *stamp)
+{
+  return s6dns_engine_init_r(dt, servers, S6DNS_O_RECURSIVE, d->s, d->len, qtype, dbh, deadline, stamp)
+   && s6dns_resolve_loop_r(dt, deadline, stamp) ;
+}
diff --git a/src/libs6dns/s6dns_resolve_dpag.c b/src/libs6dns/s6dns_resolve_dpag.c
new file mode 100644
index 0000000..7c735b8
--- /dev/null
+++ b/src/libs6dns/s6dns_resolve_dpag.c
@@ -0,0 +1,20 @@
+/* ISC license. */
+
+#include <skalibs/uint16.h>
+#include <skalibs/tai.h>
+#include <skalibs/genalloc.h>
+#include <s6-dns/s6dns-message.h>
+#include <s6-dns/s6dns-engine.h>
+#include <s6-dns/s6dns-rci.h>
+#include <s6-dns/s6dns-resolve.h>
+
+int s6dns_resolve_dpag_r (genalloc *ds, char const *name, unsigned int len, uint16 qtype, int qualif, s6dns_engine_t *dt, s6dns_rci_t const *rci, s6dns_debughook_t const *dbh, tain_t const *deadline, tain_t *stamp)
+{
+  s6dns_dpag_t data ;
+  register int r ;
+  data.ds = *ds ;
+  data.rtype = qtype ;
+  r = s6dns_resolve_r(name, len, qtype, &s6dns_message_parse_answer_domain, &data, qualif, dt, rci, dbh, deadline, stamp) ;
+  *ds = data.ds ;
+  return r ;
+}
diff --git a/src/libs6dns/s6dns_resolve_mpag.c b/src/libs6dns/s6dns_resolve_mpag.c
new file mode 100644
index 0000000..a6e04cb
--- /dev/null
+++ b/src/libs6dns/s6dns_resolve_mpag.c
@@ -0,0 +1,23 @@
+/* ISC license. */
+
+#include <skalibs/uint16.h>
+#include <skalibs/tai.h>
+#include <skalibs/stralloc.h>
+#include <skalibs/genalloc.h>
+#include <s6-dns/s6dns-message.h>
+#include <s6-dns/s6dns-engine.h>
+#include <s6-dns/s6dns-rci.h>
+#include <s6-dns/s6dns-resolve.h>
+
+int s6dns_resolve_mpag_r (stralloc *sa, genalloc *offsets, char const *name, unsigned int len, uint16 qtype, s6dns_message_rr_func_t_ref parsefunc, int qualif, s6dns_engine_t *dt, s6dns_rci_t const *rci, s6dns_debughook_t const *dbh, tain_t const *deadline, tain_t *stamp)
+{
+  s6dns_mpag_t data ;
+  register int r ;
+  data.sa = *sa ;
+  data.offsets = *offsets ;
+  data.rtype = qtype ;
+  r = s6dns_resolve_r(name, len, qtype, parsefunc, &data, qualif, dt, rci, dbh, deadline, stamp) ;
+  *sa = data.sa ;
+  *offsets = data.offsets ;
+  return r ;
+}
diff --git a/src/libs6dns/s6dns_resolve_name4.c b/src/libs6dns/s6dns_resolve_name4.c
new file mode 100644
index 0000000..7bb504a
--- /dev/null
+++ b/src/libs6dns/s6dns_resolve_name4.c
@@ -0,0 +1,23 @@
+/* ISC license. */
+
+#include <skalibs/tai.h>
+#include <skalibs/genalloc.h>
+#include <s6-dns/s6dns-constants.h>
+#include <s6-dns/s6dns-ip46.h>
+#include <s6-dns/s6dns-message.h>
+#include <s6-dns/s6dns-engine.h>
+#include <s6-dns/s6dns-resolve.h>
+
+int s6dns_resolve_name4_r (genalloc *list, char const *ip, s6dns_engine_t *dt, s6dns_ip46list_t const *servers, s6dns_debughook_t const *dbh, tain_t const *deadline, tain_t *stamp)
+{
+  s6dns_dpag_t data ;
+  s6dns_domain_t d ;
+  register int r ;
+  s6dns_domain_arpafromip4(&d, ip) ;
+  s6dns_domain_encode(&d) ;
+  data.ds = *list ;
+  data.rtype = S6DNS_T_PTR ;
+  r = s6dns_resolve_parse_r(&d, data.rtype, &s6dns_message_parse_answer_domain, &data, dt, servers, dbh, deadline, stamp) ;
+  *list = data.ds ;
+  return r ;
+}
diff --git a/src/libs6dns/s6dns_resolve_name6.c b/src/libs6dns/s6dns_resolve_name6.c
new file mode 100644
index 0000000..1af3945
--- /dev/null
+++ b/src/libs6dns/s6dns_resolve_name6.c
@@ -0,0 +1,24 @@
+/* ISC license. */
+
+#include <skalibs/tai.h>
+#include <skalibs/genalloc.h>
+#include <s6-dns/s6dns-constants.h>
+#include <s6-dns/s6dns-ip46.h>
+#include <s6-dns/s6dns-domain.h>
+#include <s6-dns/s6dns-message.h>
+#include <s6-dns/s6dns-engine.h>
+#include <s6-dns/s6dns-resolve.h>
+
+int s6dns_resolve_name6_r (genalloc *list, char const *ip, s6dns_engine_t *dt, s6dns_ip46list_t const *servers, s6dns_debughook_t const *dbh, tain_t const *deadline, tain_t *stamp)
+{
+  s6dns_dpag_t data ;
+  s6dns_domain_t d ;
+  register int r ;
+  s6dns_domain_arpafromip6(&d, ip, 128) ;
+  s6dns_domain_encode(&d) ;
+  data.ds = *list ;
+  data.rtype = S6DNS_T_PTR ;
+  r = s6dns_resolve_parse_r(&d, data.rtype, &s6dns_message_parse_answer_domain, &data, dt, servers, dbh, deadline, stamp) ;
+  *list = data.ds ;
+  return r ;
+}
diff --git a/src/libs6dns/s6dns_resolve_parse.c b/src/libs6dns/s6dns_resolve_parse.c
new file mode 100644
index 0000000..b00804f
--- /dev/null
+++ b/src/libs6dns/s6dns_resolve_parse.c
@@ -0,0 +1,21 @@
+/* ISC license. */
+
+#include <skalibs/uint16.h>
+#include <skalibs/tai.h>
+#include <s6-dns/s6dns-ip46.h>
+#include <s6-dns/s6dns-domain.h>
+#include <s6-dns/s6dns-message.h>
+#include <s6-dns/s6dns-engine.h>
+#include <s6-dns/s6dns-resolve.h>
+
+int s6dns_resolve_parse_r (s6dns_domain_t const *d, uint16 qtype, s6dns_message_rr_func_t_ref parsefunc, void *data, s6dns_engine_t *dt, s6dns_ip46list_t const *servers, s6dns_debughook_t const *dbh, tain_t const *deadline, tain_t *stamp)
+{
+  register int r ;
+  if (!s6dns_resolve_core_r(d, qtype, dt, servers, dbh, deadline, stamp)) return -1 ;
+  {
+    s6dns_message_header_t h ;
+    r = s6dns_message_parse(&h, s6dns_engine_packet(dt), s6dns_engine_packetlen(dt), parsefunc, data) ;
+  }
+  s6dns_engine_recycle(dt) ;
+  return r ;
+}
diff --git a/src/libs6dns/s6dns_resolven_loop.c b/src/libs6dns/s6dns_resolven_loop.c
new file mode 100644
index 0000000..6e0c3b4
--- /dev/null
+++ b/src/libs6dns/s6dns_resolven_loop.c
@@ -0,0 +1,54 @@
+/* ISC license. */
+
+#include <errno.h>
+#include <skalibs/tai.h>
+#include <skalibs/iopause.h>
+#include <s6-dns/s6dns-engine.h>
+#include <s6-dns/s6dns-resolve.h>
+
+ /*
+    This is basically a synchronous interface to s6dns_engine.
+    It resolves n dts at the same time.
+ */
+
+int s6dns_resolven_loop (s6dns_engine_t *dt, unsigned int n, unsigned int or, tain_t const *deadline, tain_t *stamp)
+{
+  iopause_fd x[n] ;
+  unsigned int count = 0 ;
+  for (;;)
+  {
+    tain_t localdeadline = *deadline ; 
+    register int r ;
+    register unsigned int i = 0 ;
+    register unsigned int j = 0 ;
+    for (; i < n ; i++) if (dt[i].status == EAGAIN)
+    {
+      s6dns_engine_nextdeadline(dt + i, &localdeadline) ;
+      x[j].fd = dt[i].fd ;
+      x[j].events = (s6dns_engine_isreadable(dt + i) ? IOPAUSE_READ : 0) | (s6dns_engine_iswritable(dt + i) ? IOPAUSE_WRITE : 0) ;
+      j++ ;
+    }
+    if (!j) break ;
+    r = iopause_stamp(x, j, &localdeadline, stamp) ;
+    if (r < 0) return -1 ;
+    else if (!r)
+    {
+      if (tain_less(deadline, stamp)) return (errno = ETIMEDOUT, -1) ;
+      for (i = 0 ; i < n ; i++) if (dt[i].status == EAGAIN)
+        if (s6dns_engine_timeout(dt + i, stamp) && (or >= 2)) return i ;
+    }
+    else
+    {
+      for (i = 0 ; i < n ; i++) if (dt[i].status == EAGAIN)
+      {
+        r = s6dns_engine_event(dt + i, stamp) ;
+        if (or)
+        {
+          if (r && ((r > 0) || (or >= 2))) return i ;
+        }
+        else if (r > 0) count++ ;
+      }
+    }
+  }
+  return or ? (errno = ENOENT, -1) : (int)count ;
+}
diff --git a/src/libs6dns/s6dns_resolven_parse.c b/src/libs6dns/s6dns_resolven_parse.c
new file mode 100644
index 0000000..78289bc
--- /dev/null
+++ b/src/libs6dns/s6dns_resolven_parse.c
@@ -0,0 +1,47 @@
+/* ISC license. */
+
+#include <errno.h>
+#include <skalibs/tai.h>
+#include <skalibs/iopause.h>
+#include <s6-dns/s6dns-ip46.h>
+#include <s6-dns/s6dns-message.h>
+#include <s6-dns/s6dns-engine.h>
+#include <s6-dns/s6dns-resolve.h>
+
+int s6dns_resolven_parse_r (s6dns_resolve_t *list, unsigned int n, s6dns_ip46list_t const *servers, s6dns_debughook_t const *dbh, tain_t const *deadline, tain_t *stamp)
+{
+  s6dns_engine_t dtl[n] ;
+  register unsigned int i = 0 ;
+  for (; i < n ; i++) list[i].status = ECONNABORTED ;
+  for (i = 0 ; i < n ; i++)
+  {
+    dtl[i] = s6dns_engine_zero ;
+    if (!s6dns_engine_init_r(dtl + i, servers, list[i].options, list[i].q.s, list[i].q.len, list[i].qtype, dbh, &list[i].deadline, stamp))
+    {
+      list[i].status = errno ;
+      s6dns_engine_freen(dtl, i) ;
+      return 0 ;
+    }
+    list[i].status = EAGAIN ;
+  }
+
+  if (s6dns_resolven_loop(dtl, n, 0, deadline, stamp) < 0) goto err ;
+
+  for (i = 0 ; i < n ; i++)
+  {
+    if (dtl[i].status) list[i].status = dtl[i].status ;
+    else
+    {
+      s6dns_message_header_t h ;
+      register int r = s6dns_message_parse(&h, s6dns_engine_packet(dtl + i), s6dns_engine_packetlen(dtl + i), list[i].parsefunc, list[i].data) ;
+      if (r < 0) goto err ;
+      list[i].status = r ? 0 : errno ;
+    }
+  }
+  s6dns_engine_freen(dtl, n) ;
+  return 1 ;
+
+ err:
+  s6dns_engine_freen(dtl, n) ;
+  return 0 ;
+}
diff --git a/src/libs6dns/s6dns_resolvenoq.c b/src/libs6dns/s6dns_resolvenoq.c
new file mode 100644
index 0000000..3462076
--- /dev/null
+++ b/src/libs6dns/s6dns_resolvenoq.c
@@ -0,0 +1,16 @@
+ /* ISC license. */
+
+#include <skalibs/uint16.h>
+#include <skalibs/tai.h>
+#include <s6-dns/s6dns-ip46.h>
+#include <s6-dns/s6dns-domain.h>
+#include <s6-dns/s6dns-message.h>
+#include <s6-dns/s6dns-engine.h>
+#include <s6-dns/s6dns-resolve.h>
+
+int s6dns_resolvenoq_r (char const *name, unsigned int len, uint16 qtype, s6dns_message_rr_func_t_ref parsefunc, void *data, s6dns_engine_t *dt, s6dns_ip46list_t const *servers, s6dns_debughook_t const *dbh, tain_t const *deadline, tain_t *stamp)
+{
+  s6dns_domain_t d ;
+  if (!s6dns_domain_fromstring_noqualify_encode(&d, name, len)) return -1 ;
+  return s6dns_resolve_parse_r(&d, qtype, parsefunc, data, dt, servers, dbh, deadline, stamp) ;
+}
diff --git a/src/libs6dns/s6dns_resolvenoq_aaaaa.c b/src/libs6dns/s6dns_resolvenoq_aaaaa.c
new file mode 100644
index 0000000..b280fe0
--- /dev/null
+++ b/src/libs6dns/s6dns_resolvenoq_aaaaa.c
@@ -0,0 +1,50 @@
+/* ISC license. */
+
+#include <skalibs/stralloc.h>
+#include <skalibs/genalloc.h>
+#include <skalibs/tai.h>
+#include <skalibs/ip46.h>
+#include <s6-dns/s6dns-constants.h>
+#include <s6-dns/s6dns-ip46.h>
+#include <s6-dns/s6dns-domain.h>
+#include <s6-dns/s6dns-message.h>
+#include <s6-dns/s6dns-resolve.h>
+
+int s6dns_resolvenoq_aaaaa_r (genalloc *ips, char const *name, unsigned int len, s6dns_ip46list_t const *servers, s6dns_debughook_t const *dbh, tain_t const *deadline, tain_t *stamp)
+{
+  stralloc sa[2] = { STRALLOC_ZERO, STRALLOC_ZERO } ;
+  s6dns_resolve_t blob[2] ;
+  if (!s6dns_domain_fromstring_noqualify_encode(&blob[0].q, name, len)) return -1 ;
+  blob[0].qtype = S6DNS_T_AAAA ;
+  blob[0].options = S6DNS_O_RECURSIVE ;
+  blob[0].deadline = *deadline ;
+  blob[0].parsefunc = &s6dns_message_parse_answer_aaaa ;
+  blob[0].data = &sa[0] ;
+  blob[1].q = blob[0].q ;
+  blob[1].qtype = S6DNS_T_A ;
+  blob[1].options = S6DNS_O_RECURSIVE ;
+  blob[1].deadline = *deadline ;
+  blob[1].parsefunc = &s6dns_message_parse_answer_a ;
+  blob[1].data = &sa[1] ;
+  if (!s6dns_resolven_parse_r(blob, 2, servers, dbh, deadline, stamp)) return -1 ;
+  if (blob[0].status && blob[1].status) return (errno = blob[1].status, 0) ;
+  if (!genalloc_readyplus(ip46_t, ips, (sa[0].len >> 4) + (sa[1].len >> 2)))
+  {
+    stralloc_free(&sa[0]) ;
+    stralloc_free(&sa[1]) ;
+    return -1 ;
+  }
+  {
+    unsigned int n = genalloc_len(ip46_t, ips) ;
+    int e = (!!sa[0].len << 1) | !!sa[1].len ;
+    register unsigned int i = 0 ;
+    for (; i < (sa[0].len >> 4) ; i++)
+      ip46_from_ip6(genalloc_s(ip46_t, ips) + n++, sa[0].s + (i << 4)) ;
+    for (i = 0 ; i < (sa[1].len >> 2) ; i++)
+      ip46_from_ip4(genalloc_s(ip46_t, ips) + n++, sa[1].s + (i << 2)) ;
+    genalloc_setlen(ip46_t, ips, n) ;
+    stralloc_free(&sa[0]) ;
+    stralloc_free(&sa[1]) ;
+    return e ;
+  }
+}
diff --git a/src/libs6dns/s6dns_resolveq.c b/src/libs6dns/s6dns_resolveq.c
new file mode 100644
index 0000000..c43db1f
--- /dev/null
+++ b/src/libs6dns/s6dns_resolveq.c
@@ -0,0 +1,89 @@
+/* ISC license. */
+
+#include <errno.h>
+#include <skalibs/uint16.h>
+#include <skalibs/error.h>
+#include <skalibs/tai.h>
+#include <s6-dns/s6dns-domain.h>
+#include <s6-dns/s6dns-message.h>
+#include <s6-dns/s6dns-engine.h>
+#include <s6-dns/s6dns-rci.h>
+#include <s6-dns/s6dns-resolve.h>
+
+int s6dns_resolveq_r (char const *name, unsigned int len, uint16 qtype, s6dns_message_rr_func_t_ref parsefunc, void *data, s6dns_rci_t const *rci, s6dns_debughook_t const *dbh, tain_t const *deadline, tain_t *stamp)
+{
+  s6dns_engine_t dtl[rci->rulesnum] ;
+  unsigned int best = 0 ;
+  unsigned int n ;
+  int e = 0 ;
+  register unsigned int i = 0 ;
+  {
+    s6dns_domain_t domains[rci->rulesnum] ;
+    n = s6dns_domain_fromstring_qualify_encode(domains, name, len, rci->rules.s, rci->rulesnum) ;
+    if (!n) return -1 ;
+    for (; i < n ; i++)
+    {
+      dtl[i] = s6dns_engine_zero ;
+      if (!s6dns_engine_init_r(dtl + i, &rci->servers, S6DNS_O_RECURSIVE, domains[i].s, domains[i].len, qtype, dbh, deadline, stamp))
+      {
+        s6dns_engine_freen(dtl, i) ;
+        return -1 ;
+      }
+    }
+  }
+
+ /*
+    Wait until the "best" answer arrives, then scan until a positive answer
+    is found.
+    
+    dtl[i].status == EAGAIN : query still pending
+    other nonzero dtl[i].status : error, give up
+    dtl[i].status == 0 : answer #i has arrived, in which case parse it;
+      r < 0 : error, give up
+      r > 0 : positive answer, return it
+      r == 0 : negative answer. If it's non-fatal (i.e. NXDOMAIN),
+       then move on to the next best FQDN.
+ */
+
+  for (;;)
+  {
+    register int k = s6dns_resolven_loop(dtl, n, 1, deadline, stamp) ;
+    if (k < 0) goto err ;
+    if ((unsigned int)k == best)
+    {
+      for (;; best++)
+      {
+        s6dns_message_header_t h ;
+        register int r ;
+        if (best >= n) goto notfound ;
+        if (error_isagain(dtl[best].status)) break ;
+        if (dtl[best].status) { errno = dtl[best].status ; goto err ; }
+        r = s6dns_message_parse(&h, s6dns_engine_packet(dtl + best), s6dns_engine_packetlen(dtl + best), parsefunc, data) ;
+        if (r < 0) goto err ;
+        else if (r) goto found ;
+        else switch (errno)
+        {
+          case EBUSY :
+          case ENOENT :
+          case ECONNREFUSED :
+          case EIO :
+            break ;
+          default : goto err ;
+        }
+        if (!best) e = errno ;
+      }
+    }
+  }
+
+ found:
+  s6dns_engine_freen(dtl, n) ;
+  return 1 ;
+
+ notfound:
+  s6dns_engine_freen(dtl, n) ;
+  return (errno = e, 0) ;
+
+ err:
+  s6dns_engine_freen(dtl, n) ;
+  return -1 ;
+}
diff --git a/src/libs6dns/s6dns_resolveq_aaaaa.c b/src/libs6dns/s6dns_resolveq_aaaaa.c
new file mode 100644
index 0000000..825e68e
--- /dev/null
+++ b/src/libs6dns/s6dns_resolveq_aaaaa.c
@@ -0,0 +1,96 @@
+/* ISC license. */
+
+#include <errno.h>
+#include <skalibs/uint16.h>
+#include <skalibs/error.h>
+#include <skalibs/stralloc.h>
+#include <skalibs/genalloc.h>
+#include <skalibs/tai.h>
+#include <skalibs/ip46.h>
+#include <s6-dns/s6dns-domain.h>
+#include <s6-dns/s6dns-message.h>
+#include <s6-dns/s6dns-engine.h>
+#include <s6-dns/s6dns-rci.h>
+#include <s6-dns/s6dns-resolve.h>
+
+int s6dns_resolveq_aaaaa_r (genalloc *ips, char const *name, unsigned int len, s6dns_rci_t const *rci, s6dns_debughook_t const *dbh, tain_t const *deadline, tain_t *stamp)
+{
+  s6dns_engine_t dtl[rci->rulesnum << 1] ;
+  stralloc data = STRALLOC_ZERO ;
+  unsigned int best = 0 ;
+  unsigned int n ;
+  int e = 0 ;
+  register unsigned int i = 0 ;
+  {
+    s6dns_domain_t domains[rci->rulesnum] ;
+    n = s6dns_domain_fromstring_qualify_encode(domains, name, len, rci->rules.s, rci->rulesnum) ;
+    if (!n) return -1 ;
+    for (; i < n ; i++)
+    {
+      dtl[i<<1] = s6dns_engine_zero ;
+      if (!s6dns_engine_init_r(dtl + (i<<1), &rci->servers, S6DNS_O_RECURSIVE, domains[i].s, domains[i].len, S6DNS_T_AAAA, dbh, deadline, stamp))
+      {
+        s6dns_engine_freen(dtl, i<<1) ;
+        return -1 ;
+      }
+      dtl[(i<<1)+1] = s6dns_engine_zero ;
+      if (!s6dns_engine_init_r(dtl + (i<<1) + 1, &rci->servers, S6DNS_O_RECURSIVE, domains[i].s, domains[i].len, S6DNS_T_A, dbh, deadline, stamp))
+      {
+        s6dns_engine_freen(dtl, (i<<1)+1) ;
+        return -1 ;
+      }
+    }
+  }
+
+  for (;;)
+  {
+    register int k = s6dns_resolven_loop(dtl, n << 1, 1, deadline, stamp) ;
+    if (k < 0) goto err ;
+    if ((unsigned int)k == best)
+    {
+      for (;; best++)
+      {
+        s6dns_message_header_t h ;
+        register int r ;
+        if (best >= n << 1) goto notfound ;
+        if (error_isagain(dtl[best].status)) break ;
+        if (dtl[best].status) { errno = dtl[best].status ; goto err ; }
+        r = s6dns_message_parse(&h, s6dns_engine_packet(dtl + best), s6dns_engine_packetlen(dtl + best), (best & 1) ? &s6dns_message_parse_answer_a : s6dns_message_parse_answer_aaaa, &data) ;
+        if (r < 0) goto err ;
+        else if (r) goto found ;
+        else switch (errno)
+        {
+          case EBUSY :
+          case ENOENT :
+          case ECONNREFUSED :
+          case EIO :
+            break ;
+          default : goto err ;
+        }
+        if (!best) e = errno ;
+      }
+    }
+  }
+
+ found:
+  s6dns_engine_freen(dtl, n<<1) ;
+  {
+    register unsigned int len = data.len >> ((best & 1) ? 2 : 4) ;
+    register unsigned int i = 0 ;
+    register unsigned int base = genalloc_len(ip46_t, ips) ;
+    if (!genalloc_readyplus(ip46_t, ips, len)) return -1 ;
+    for (; i < len ; i++)
+      ip46_from_ip(genalloc_s(ip46_t, ips) + base + i, data.s + (i << ((best & 1) ? 2 : 4)), !(best & 1)) ;
+    genalloc_setlen(ip46_t, ips, base + len) ;
+  }
+  stralloc_free(&data) ;
+  return 1 ;
+
+ notfound:
+  s6dns_engine_freen(dtl, n<<1) ;
+  return (errno = e, 0) ;
+
+ err:
+  s6dns_engine_freen(dtl, n<<1) ;
+  return -1 ;
+}
diff --git a/src/skadns/deps-exe/skadnsd b/src/skadns/deps-exe/skadnsd
new file mode 100755
index 0000000..4181fd6
--- /dev/null
+++ b/src/skadns/deps-exe/skadnsd
@@ -0,0 +1,4 @@
+-ls6dns
+-lskarnet
+${SOCKET_LIB}
+${TAINNOW_LIB}
diff --git a/src/skadns/deps-lib/skadns b/src/skadns/deps-lib/skadns
new file mode 100644
index 0000000..570a6f5
--- /dev/null
+++ b/src/skadns/deps-lib/skadns
@@ -0,0 +1,10 @@
+skadns_cancel.o
+skadns_end.o
+skadns_packet.o
+skadns_packetlen.o
+skadns_release.o
+skadns_send.o
+skadns_start.o
+skadns_startf.o
+skadns_update.o
+skadns_zero.o
diff --git a/src/skadns/skadns_cancel.c b/src/skadns/skadns_cancel.c
new file mode 100644
index 0000000..13db918
--- /dev/null
+++ b/src/skadns/skadns_cancel.c
@@ -0,0 +1,23 @@
+/* ISC license. */
+
+#include <errno.h>
+#include <skalibs/uint16.h>
+#include <skalibs/error.h>
+#include <skalibs/tai.h>
+#include <skalibs/gensetdyn.h>
+#include <skalibs/skaclient.h>
+#include <s6-dns/skadns.h>
+
+int skadns_cancel (skadns_t *a, uint16 id, tain_t const *deadline, tain_t *stamp)
+{
+  char pack[3] = "--q" ;
+  char err ;
+  register skadnsanswer_t *p = GENSETDYN_P(skadnsanswer_t, &a->q, id) ;
+  if (!error_isagain(p->status)) return skadns_release(a, id) ;
+  uint16_pack_big(pack, id) ;
+  if (!skaclient_send(&a->connection, pack, 3, &skaclient_default_cb, &err, deadline, stamp)) return 0 ;
+  if (!err) return gensetdyn_delete(&a->q, id) ;
+  if (err != ENOENT) return (errno = err, 0) ;
+  p->status = ECANCELED ;
+  return 1 ;
+}
diff --git a/src/skadns/skadns_end.c b/src/skadns/skadns_end.c
new file mode 100644
index 0000000..6f5f01b
--- /dev/null
+++ b/src/skadns/skadns_end.c
@@ -0,0 +1,24 @@
+/* ISC license. */
+
+#include <skalibs/alloc.h>
+#include <skalibs/genalloc.h>
+#include <skalibs/gensetdyn.h>
+#include <skalibs/skaclient.h>
+#include <s6-dns/skadns.h>
+
+static int skadnsanswer_free (char *p, void *stuff)
+{
+  register skadnsanswer_t *q = (skadnsanswer_t_ref)p ;
+  alloc_free(&q->data) ;
+  (void)stuff ;
+  return 1 ;
+}
+
+void skadns_end (skadns_t *a)
+{
+  skaclient_end(&a->connection) ;
+  genalloc_free(uint16, &a->list) ;
+  gensetdyn_iter(&a->q, &skadnsanswer_free, 0) ;
+  gensetdyn_free(&a->q) ;
+  *a = skadns_zero ;
+}
diff --git a/src/skadns/skadns_packet.c b/src/skadns/skadns_packet.c
new file mode 100644
index 0000000..c34b3a1
--- /dev/null
+++ b/src/skadns/skadns_packet.c
@@ -0,0 +1,16 @@
+/* ISC license. */
+
+#include <errno.h>
+#include <skalibs/uint16.h>
+#include <skalibs/gensetdyn.h>
+#include <s6-dns/skadns.h>
+
+char const *skadns_packet (skadns_t const *a, uint16 id)
+{
+  register skadnsanswer_t *p = GENSETDYN_P(skadnsanswer_t, &a->q, id) ;
+  switch (p->status)
+  {
+    case 0 : return (char const *)p->data ;
+    default : return (errno = p->status, (char const *)0) ;
+  }
+}
diff --git a/src/skadns/skadns_packetlen.c b/src/skadns/skadns_packetlen.c
new file mode 100644
index 0000000..34cbb28
--- /dev/null
+++ b/src/skadns/skadns_packetlen.c
@@ -0,0 +1,16 @@
+/* ISC license. */
+
+#include <errno.h>
+#include <skalibs/uint16.h>
+#include <skalibs/gensetdyn.h>
+#include <s6-dns/skadns.h>
+
+int skadns_packetlen (skadns_t const *a, uint16 id)
+{
+  register skadnsanswer_t *p = GENSETDYN_P(skadnsanswer_t, &a->q, id) ;
+  switch (p->status)
+  {
+    case 0 : return p->len ;
+    default : return (errno = p->status, -1) ;
+  }
+}
diff --git a/src/skadns/skadns_release.c b/src/skadns/skadns_release.c
new file mode 100644
index 0000000..9fba737
--- /dev/null
+++ b/src/skadns/skadns_release.c
@@ -0,0 +1,26 @@
+/* ISC license. */
+
+#include <errno.h>
+#include <skalibs/uint16.h>
+#include <skalibs/alloc.h>
+#include <skalibs/gensetdyn.h>
+#include <s6-dns/skadns.h>
+
+int skadns_release (skadns_t *a, uint16 id)
+{
+  register skadnsanswer_t *p = GENSETDYN_P(skadnsanswer_t, &a->q, id) ;
+  switch (p->status)
+  {
+    case 0 :
+      alloc_free(p->data) ; p->data = 0 ; p->len = 0 ;
+      break ;
+    case EAGAIN :
+    case ECANCELED :
+      return (errno = EBUSY, 0) ;
+    case EINVAL :
+      return (errno = EINVAL, 0) ;
+    default : break ;
+  }
+  p->status = EINVAL ;
+  return gensetdyn_delete(&a->q, id) ;
+}
diff --git a/src/skadns/skadns_send.c b/src/skadns/skadns_send.c
new file mode 100644
index 0000000..7ee04c7
--- /dev/null
+++ b/src/skadns/skadns_send.c
@@ -0,0 +1,41 @@
+/* ISC license. */
+
+#include <errno.h>
+#include <skalibs/uint16.h>
+#include <skalibs/bytestr.h>
+#include <skalibs/siovec.h>
+#include <skalibs/tai.h>
+#include <skalibs/stralloc.h>
+#include <skalibs/gensetdyn.h>
+#include <skalibs/skaclient.h>
+#include <s6-dns/s6dns-domain.h>
+#include <s6-dns/skadns.h>
+
+static skadnsanswer_t const skadnsanswer_initial = { .status = EAGAIN, .data = 0, .len = 0 } ;
+
+int skadns_send (skadns_t *a, uint16 *u, s6dns_domain_t const *d, uint16 qtype, tain_t const *limit, tain_t const *deadline, tain_t *stamp)
+{
+  unsigned int i ;
+  char tmp[17] = "--Q" ;
+  char err ;
+  siovec_t v[2] = { { .s = tmp, .len = 17 }, { .s = d->s, .len = d->len } } ;
+  if (!gensetdyn_new(&a->q, &i)) return 0 ;
+  uint16_pack_big(tmp, (uint16)i) ;
+  uint16_pack_big(tmp + 3, qtype) ;
+  if (limit) tain_pack(tmp + 5, limit) ; else byte_zero(tmp + 5, 12) ;
+  if (!skaclient_sendv(&a->connection, v, 2, &skaclient_default_cb, &err, deadline, stamp))
+  {
+    register int e = errno ;
+    gensetdyn_delete(&a->q, i) ;
+    errno = e ;
+    return 0 ;
+  }
+  if (err)
+  {
+    gensetdyn_delete(&a->q, i) ;
+    return (errno = err, 0) ;
+  }
+  *GENSETDYN_P(skadnsanswer_t, &a->q, i) = skadnsanswer_initial ;
+  *u = i ;
+  return 1 ;
+}
diff --git a/src/skadns/skadns_start.c b/src/skadns/skadns_start.c
new file mode 100644
index 0000000..3dccb54
--- /dev/null
+++ b/src/skadns/skadns_start.c
@@ -0,0 +1,10 @@
+/* ISC license. */
+
+#include <skalibs/tai.h>
+#include <skalibs/skaclient.h>
+#include <s6-dns/skadns.h>
+
+int skadns_start (skadns_t *a, char const *path, tain_t const *deadline, tain_t *stamp)
+{
+  return skaclient_start_b(&a->connection, &a->buffers, path, SKADNS_BANNER1, SKADNS_BANNER1_LEN, SKADNS_BANNER2, SKADNS_BANNER2_LEN, deadline, stamp) ;
+}
diff --git a/src/skadns/skadns_startf.c b/src/skadns/skadns_startf.c
new file mode 100644
index 0000000..ac19a0c
--- /dev/null
+++ b/src/skadns/skadns_startf.c
@@ -0,0 +1,12 @@
+/* ISC license. */
+
+#include <skalibs/environ.h>
+#include <skalibs/tai.h>
+#include <skalibs/skaclient.h>
+#include <s6-dns/skadns.h>
+
+int skadns_startf (skadns_t *a, tain_t const *deadline, tain_t *stamp)
+{
+  static char const *const cargv[2] = { SKADNSD_PROG, 0 } ;
+  return skaclient_startf_b(&a->connection, &a->buffers, cargv[0], cargv, (char const *const *)environ, SKACLIENT_OPTION_WAITPID, SKADNS_BANNER1, SKADNS_BANNER1_LEN, SKADNS_BANNER2, SKADNS_BANNER2_LEN, deadline, stamp) ;
+}
diff --git a/src/skadns/skadns_update.c b/src/skadns/skadns_update.c
new file mode 100644
index 0000000..50f3611
--- /dev/null
+++ b/src/skadns/skadns_update.c
@@ -0,0 +1,45 @@
+/* ISC license. */
+
+#include <errno.h>
+#include <skalibs/error.h>
+#include <skalibs/uint16.h>
+#include <skalibs/alloc.h>
+#include <skalibs/bytestr.h>
+#include <skalibs/genalloc.h>
+#include <skalibs/gensetdyn.h>
+#include <skalibs/unixmessage.h>
+#include <skalibs/skaclient.h>
+#include <s6/skadns.h>
+
+static int msghandler (unixmessage_t const *m, void *context)
+{
+  skadns_t *a = (skadns_t *)context ;
+  skadnsanswer_t *p ;
+  uint16 id ;
+  if (m->len < 3 || m->nfds) return (errno = EPROTO, 0) ;
+  uint16_unpack_big(m->s, &id) ;
+  p = GENSETDYN_P(skadnsanswer_t, &a->q, id) ;
+  if (p->status == ECANCELED)
+  {
+    p->status = EINVAL ;
+    return gensetdyn_delete(&a->q, id) ;
+  }
+  if (!error_isagain(p->status)) return (errno = EINVAL, 0) ;
+  if (!genalloc_readyplus(uint16, &a->list, 1)) return 0 ;
+  if (!m->s[2])
+  {
+    p->data = alloc(m->len-3) ;
+    if (!p->data) return 0 ;
+    byte_copy(p->data, m->len-3, m->s+3) ;
+    p->len = m->len-3 ;
+  }
+  p->status = m->s[2] ;
+  genalloc_append(uint16, &a->list, &id) ;
+  return 1 ;
+}
+
+int skadns_update (skadns_t *a)
+{
+  genalloc_setlen(uint16, &a->list, 0) ;
+  return skaclient_update(&a->connection, &msghandler, a) ;
+}
diff --git a/src/skadns/skadns_zero.c b/src/skadns/skadns_zero.c
new file mode 100644
index 0000000..1842d2e
--- /dev/null
+++ b/src/skadns/skadns_zero.c
@@ -0,0 +1,5 @@
+/* ISC license. */
+
+#include <s6-dns/skadns.h>
+
+skadns_t const skadns_zero = SKADNS_ZERO ;
diff --git a/src/skadns/skadnsd.c b/src/skadns/skadnsd.c
new file mode 100644
index 0000000..7b5419f
--- /dev/null
+++ b/src/skadns/skadnsd.c
@@ -0,0 +1,199 @@
+/* ISC license. */
+
+#include <errno.h>
+#include <signal.h>
+#include <skalibs/uint16.h>
+#include <skalibs/error.h>
+#include <skalibs/strerr2.h>
+#include <skalibs/sig.h>
+#include <skalibs/tai.h>
+#include <skalibs/djbunix.h>
+#include <skalibs/iopause.h>
+#include <skalibs/unixmessage.h>
+#include <skalibs/skaclient.h>
+#include <s6-dns/s6dns.h>
+#include <s6-dns/skadns.h>
+
+typedef struct dnsio_s dnsio_t, *dnsio_t_ref ;
+struct dnsio_s
+{
+  unsigned int xindex ;
+  s6dns_engine_t dt ;
+  uint16 id ;
+} ;
+#define DNSIO_ZERO { .xindex = SKADNS_MAXCONCURRENCY, .dt = S6DNS_ENGINE_ZERO, .id = 0 }
+
+static dnsio_t a[SKADNS_MAXCONCURRENCY] ;
+static unsigned int sp = 0 ;
+
+static void remove (unsigned int i)
+{
+  dnsio_t tmp ;
+  tmp = a[sp-1] ;
+  a[--sp] = a[i] ;
+  a[i] = tmp ;
+}
+
+static void fail (unsigned int i)
+{
+  char pack[3] ;
+  unixmessage_t m = { .s = pack, len = 3, .fds = 0, .nfds = 0 } ;
+  uint16_pack_big(pack, a[i].id) ;
+  pack[2] = a[i].dt.status ;
+  s6dns_engine_recycle(&a[i].dt) ;
+  remove(i) ;
+  if (!unixmessage_put(unixmessage_sender_x, &m))
+    strerr_diefu1sys(111, "unixmessage_put") ;
+}
+
+static void answer (char c)
+{
+  unixmessage_t m = { .s = &c, .len = 1, .fds = 0, .nfds = 0 } ;
+  if (!unixmessage_put(unixmessage_sender_1, &m))
+    strerr_diefu1sys(111, "unixmessage_put") ;
+}
+
+static int parse_protocol (unixmessage_t const *m, void *context)
+{
+  uint16 id ;
+  if (m->len < 3 || m->nfds) strerr_dief1x(100, "invalid client request") ;
+  uint16_unpack_big(m->s, &id) ;
+  switch (m->s[2])  /* protocol parsing */
+  {
+    case 'Q' : /* send a query */
+    {
+      tain_t limit ;
+      uint16 qtype ;
+      if (m->len < 21) strerr_dief1x(100, "invalid client request") ;
+      if (sp >= SKADNS_MAXCONCURRENCY)
+      {
+        answer(ENFILE) ;
+        break ;
+      }
+      uint16_unpack_big(m->s + 3, &qtype) ;
+      if (byte_diff(m->s + 5, 12, "\0\0\0\0\0\0\0\0\0\0\0"))
+        tain_unpack(m->s + 5, &limit) ;
+      else tain_add_g(&limit, &tain_infinite_relative) ;
+      if (!s6dns_engine_init_g(&a[sp].dt, &s6dns_rci_here.servers, 1, m->s + 17, m->len - 17, qtype, &limit))
+      {
+        answer(errno) ;
+        break ;
+      }
+      a[sp++].id = id ;
+      answer(0) ;
+      break ;
+    }
+    case 'q' : /* cancel a query */
+    {
+      register unsigned int i = 0 ;
+      for (; i < sp ; i++) if (a[i].id == id) break ;
+      if (i >= sp)
+      {
+        answer(ENOENT) ;
+        break ;
+      }
+      s6dns_engine_recycle(&a[i].dt) ;
+      remove(i) ;
+      answer(0) ;
+      break ;
+    }
+    default : strerr_dief1x(100, "invalid client request") ;
+  }
+  (void)context ;
+  return 1 ;
+}
+
+int main (void)
+{
+  PROG = "skadnsd" ;
+
+  if (ndelay_on(0) < 0) strerr_diefu2sys(111, "ndelay_on ", "0") ;
+  if (ndelay_on(1) < 0) strerr_diefu2sys(111, "ndelay_on ", "1") ;
+  if (sig_ignore(SIGPIPE) < 0) strerr_diefu1sys(111, "ignore SIGPIPE") ;
+  tain_now_g() ;
+  if (!s6dns_init()) strerr_diefu1sys(111, "s6dns_init") ;
+
+  {
+    tain_t deadline ;
+    tain_addsec_g(&deadline, 2) ;
+    if (!skaclient_server_01x_init_g(SKADNS_BANNER1, SKADNS_BANNER1_LEN, SKADNS_BANNER2, SKADNS_BANNER2_LEN, &deadline))
+      strerr_diefu1sys(111, "sync with client") ;
+  }
+  {
+    static dnsio_t const zero = DNSIO_ZERO ;
+    register unsigned int i = 0 ;
+    for (; i < SKADNS_MAXCONCURRENCY ; i++) a[i] = zero ;
+  }
+                  
+  for (;;)                
+  {
+    iopause_fd x[3 + sp] ;
+    register int r ;
+    
+    x[0].fd = 0 ; x[0].events = IOPAUSE_EXCEPT | IOPAUSE_READ ;
+    x[1].fd = 1 ; x[1].events = IOPAUSE_EXCEPT | (unixmessage_sender_isempty(unixmessage_sender_1) ? 0 : IOPAUSE_WRITE) ;
+    x[2].fd = unixmessage_sender_fd(unixmessage_sender_x) ;
+    x[2].events = IOPAUSE_EXCEPT | (unixmessage_sender_isempty(unixmessage_sender_x) ? 0 : IOPAUSE_WRITE) ;
+    {
+      tain_t deadline = TAIN_INFINITE ;
+      register unsigned int i = 0 ;
+      for (; i < sp ; i++)
+      {
+        register unsigned int j = 3 + i ;
+        s6dns_engine_nextdeadline(&a[i].dt, &deadline) ;
+        x[j].fd = a[i].dt.fd ;
+        x[j].events = 0 ;
+        if (s6dns_engine_isreadable(&a[i].dt)) x[j].events |= IOPAUSE_READ ;
+        if (s6dns_engine_iswritable(&a[i].dt)) x[j].events |= IOPAUSE_WRITE ;
+        a[i].xindex = j ;
+      }
+      r = iopause_g(x, 3 + sp, &deadline) ;
+    }
+    if (r < 0) strerr_diefu1sys(111, "iopause") ;
+    if (!r) 
+    {
+      register unsigned int i = 0 ;
+      for (; i < sp ; i++)
+        if (s6dns_engine_timeout_g(&a[i].dt)) fail(i--) ;
+      continue ;
+    }
+
+    if (x[1].revents & IOPAUSE_WRITE)
+      if ((unixmessage_sender_flush(unixmessage_sender_1) < 0) && !error_isagain(errno))
+        strerr_diefu1sys(111, "flush stdout") ;
+    if (x[2].revents & IOPAUSE_WRITE)
+      if ((unixmessage_sender_flush(unixmessage_sender_x) < 0) && !error_isagain(errno))
+        strerr_diefu1sys(111, "flush asyncout") ;
+                        
+    {
+      register unsigned int i = 0 ;
+      for (; i < sp ; i++) if (x[a[i].xindex].revents)
+      {
+        register int r = s6dns_engine_event_g(&a[i].dt) ;
+        if (r < 0) fail(i--) ;
+        else if (r)
+        {
+          char pack[3] ;
+          siovec_t v[2] = { { .s = pack, .len = 3 }, { .s = s6dns_engine_packet(&a[i].dt), .len = s6dns_engine_packetlen(&a[i].dt) } } ;
+          unixmessage_v_t mv = { .v = v, .vlen = 2, .fds = 0, .nfds = 0 } ;
+          uint16_pack_big(pack, a[i].id) ;
+          pack[2] = 0 ;
+          if (!unixmessage_putv(unixmessage_sender_x, v, 2))
+            strerr_diefu1sys(111, "unixmessage_put") ;
+          s6dns_engine_recycle(&a[i].dt) ;
+          remove(i--) ;
+        }
+      }
+    }
+
+    if (!unixmessage_receiver_isempty(unixmessage_receiver_0) || x[0].revents & IOPAUSE_READ)
+    {
+      if (unixmessage_handle(unixmessage_receiver_0, &parse_protocol, 0) < 0)
+      {
+        if (errno == EPIPE) break ; /* normal exit */
+        strerr_diefu1sys(111, "handle messages from client") ;
+      }
+    }
+  }
+  return 0 ;
+}