Start work on bearssl server-side sni

10 files changed, 372 insertions, 0 deletions

diff --git a/src/include/s6-networking/sbearssl.h b/src/include/s6-networking/sbearssl.h
index 8de12ab..83bc376 100644
--- a/src/include/s6-networking/sbearssl.h
+++ b/src/include/s6-networking/sbearssl.h
@@ -13,6 +13,7 @@
 #include <skalibs/stralloc.h>
 #include <skalibs/genalloc.h>
 #include <skalibs/tai.h>
+#include <skalibs/avltree.h>
 
  /*
   * Support library for bearssl.
@@ -153,6 +154,7 @@ extern int sbearssl_skey_from (sbearssl_skey *, br_skey const *, stralloc *) ;
 extern int sbearssl_skey_to (sbearssl_skey const *, br_skey *, char *) ;
 
 extern int sbearssl_skey_readfile (char const *, sbearssl_skey *, stralloc *) ;
+extern void sbearssl_skey_wipe (sbearssl_skey, char *) ;
 
 
  /* Public keys */
@@ -262,6 +264,36 @@ extern int sbearssl_send_environment (br_ssl_engine_context *, sbearssl_handshak
 extern void sbearssl_run (br_ssl_engine_context *, int *, tain_t const *, uint32_t, unsigned int, sbearssl_handshake_cbfunc_ref, sbearssl_handshake_cbarg *) gccattr_noreturn ;
 
 
+ /* Generic server policy class and server-side SNI implementation */
+
+typedef struct sbearssl_sni_map_s sbearssl_sni_map, *sbearssl_sni_map_ref ;
+struct sbearssl_sni_map_s
+{
+  char const *servername ;
+  sbearssl_skey skey ;
+  size_t chainindex ;
+  size_t chainlen ;
+} ;
+
+typedef struct sbearssl_sni_policy_context_s sbearssl_sni_policy_context, *sbearssl_sni_policy_context_ref ;
+struct sbearssl_sni_policy_context_s
+{
+  br_ssl_server_policy_class const *vtable ;
+  br_skey skey ;
+  avltree map ;
+  genalloc mapga ;
+  genalloc certga ;
+  stralloc storage ;
+}
+
+extern br_ssl_server_policy_class const sbearssl_sni_policy_vtable ;
+extern int sbearssl_sni_policy_init (sbearssl_sni_policy_context *) ;
+extern int sbearssl_sni_policy_add_keypair_file (sbearssl_sni_policy_context *, char const *, char const *, char const *) ;
+
+extern void sbearssl_sctx_init_full_generic (br_ssl_server_context *) ;
+extern void sbearssl_sctx_set_policy_sni (br_ssl_server_context *, sbearssl_sni_policy_context *) ;
+
+
  /* s6-tlsc-io and s6-tlsd-io implementations */
 
 extern void sbearssl_client_init_and_run (int *, tain_t const *, uint32_t, uint32_t, unsigned int, char const *, sbearssl_handshake_cbfunc_ref, sbearssl_handshake_cbarg *) gccattr_noreturn ;
diff --git a/src/sbearssl/deps-lib/sbearssl b/src/sbearssl/deps-lib/sbearssl
index 68b3ce1..c0d4507 100644
--- a/src/sbearssl/deps-lib/sbearssl
+++ b/src/sbearssl/deps-lib/sbearssl
@@ -24,8 +24,11 @@ sbearssl_rsa_pkey_to.o
 sbearssl_rsa_skey_from.o
 sbearssl_rsa_skey_to.o
 sbearssl_run.o
+sbearssl_sctx_init_full_generic.o
+sbearssl_sctx_set_policy_sni.o
 sbearssl_send_environment.o
 sbearssl_server_init_and_run.o
+sbearssl_sni_policy_vtable.o
 sbearssl_skey_from.o
 sbearssl_skey_readfile.o
 sbearssl_skey_to.o
diff --git a/src/sbearssl/sbearssl-internal.h b/src/sbearssl/sbearssl-internal.h
index 21a28d7..d8e0c57 100644
--- a/src/sbearssl/sbearssl-internal.h
+++ b/src/sbearssl/sbearssl-internal.h
@@ -75,4 +75,13 @@ extern int sbearssl_pem_push (br_pem_decoder_context *, char const *, size_t, sb
 extern sbearssl_suiteinfo const *const sbearssl_suite_list ;
 extern size_t const sbearssl_suite_list_len ;
 
+typedef struct sbearssl_sni_policy_node_s sbearssl_sni_policy_node, *sbearssl_policy_node_ref ;
+struct sbearssl_sni_policy_node_s
+{
+  size_t servername ;
+  sbearssl_skey skey ;
+  size_t chainindex ;
+  size_t chainlen ;
+} ;
+
 #endif
diff --git a/src/sbearssl/sbearssl_sctx_init_full_generic.c b/src/sbearssl/sbearssl_sctx_init_full_generic.c
new file mode 100644
index 0000000..2c930c8
--- /dev/null
+++ b/src/sbearssl/sbearssl_sctx_init_full_generic.c
@@ -0,0 +1,87 @@
+/* ISC license. */
+
+#include <stdint.h>
+
+#include <bearssl.h>
+
+#include <s6-networking/sbearssl.h>
+
+static uint16_t const suites[] =
+{
+    BR_TLS_ECDHE_ECDSA_WITH_CHACHA20_POLY1305_SHA256,  /* ec cipher */
+  BR_TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256,     /* rsa cipher */
+    BR_TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256,
+  BR_TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256,
+    BR_TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384,
+  BR_TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384,
+    BR_TLS_ECDHE_ECDSA_WITH_AES_128_CCM,
+  BR_TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256,
+    BR_TLS_ECDHE_ECDSA_WITH_AES_256_CCM,
+    BR_TLS_ECDHE_ECDSA_WITH_AES_128_CCM_8,
+    BR_TLS_ECDHE_ECDSA_WITH_AES_256_CCM_8,
+    BR_TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA256,
+    BR_TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA384,
+  BR_TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384,
+    BR_TLS_ECDHE_ECDSA_WITH_AES_128_CBC_SHA,
+  BR_TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA,
+    BR_TLS_ECDHE_ECDSA_WITH_AES_256_CBC_SHA,
+  BR_TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA,
+    BR_TLS_ECDH_ECDSA_WITH_AES_128_GCM_SHA256,
+    BR_TLS_ECDH_RSA_WITH_AES_128_GCM_SHA256,
+  BR_TLS_RSA_WITH_AES_128_GCM_SHA256,
+    BR_TLS_ECDH_ECDSA_WITH_AES_256_GCM_SHA384,
+    BR_TLS_ECDH_RSA_WITH_AES_256_GCM_SHA384,
+  BR_TLS_RSA_WITH_AES_256_GCM_SHA384,
+    BR_TLS_ECDH_ECDSA_WITH_AES_128_CBC_SHA256,
+  BR_TLS_RSA_WITH_AES_128_CCM,
+    BR_TLS_ECDH_RSA_WITH_AES_128_CBC_SHA256,
+  BR_TLS_RSA_WITH_AES_256_CCM,
+    BR_TLS_ECDH_ECDSA_WITH_AES_256_CBC_SHA384,
+  BR_TLS_RSA_WITH_AES_128_CCM_8,
+    BR_TLS_ECDH_RSA_WITH_AES_256_CBC_SHA384,
+  BR_TLS_RSA_WITH_AES_256_CCM_8,
+    BR_TLS_ECDH_ECDSA_WITH_AES_128_CBC_SHA,
+  BR_TLS_RSA_WITH_AES_128_CBC_SHA256,
+    BR_TLS_ECDH_RSA_WITH_AES_128_CBC_SHA,
+  BR_TLS_RSA_WITH_AES_256_CBC_SHA256,
+    BR_TLS_ECDH_ECDSA_WITH_AES_256_CBC_SHA,
+  BR_TLS_RSA_WITH_AES_128_CBC_SHA,
+    BR_TLS_ECDH_RSA_WITH_AES_256_CBC_SHA,
+  BR_TLS_RSA_WITH_AES_256_CBC_SHA,
+    BR_TLS_ECDHE_ECDSA_WITH_3DES_EDE_CBC_SHA,
+  BR_TLS_ECDHE_RSA_WITH_3DES_EDE_CBC_SHA,
+    BR_TLS_ECDH_ECDSA_WITH_3DES_EDE_CBC_SHA,
+  BR_TLS_RSA_WITH_3DES_EDE_CBC_SHA,
+    BR_TLS_ECDH_RSA_WITH_3DES_EDE_CBC_SHA
+} ;
+
+static br_hash_class const *hashes[] =
+{
+  &br_md5_vtable,
+  &br_sha1_vtable,
+  &br_sha224_vtable,
+  &br_sha256_vtable,
+  &br_sha384_vtable,
+  &br_sha512_vtable
+} ;
+
+void sbearssl_sctx_init_full_generic (br_ssl_server_context *sc)
+{
+  br_ssl_server_zero(sc) ;
+  br_ssl_engine_set_versions(&sc->eng, BR_TLS10, BR_TLS12) ;
+  br_ssl_engine_set_suites(&sc->eng, suites, sizeof(suites) / sizeof(suites[0])) ;
+  br_ssl_engine_set_default_ec(&sc->eng) ;
+
+  for (unsigned int i = br_md5_ID ; i <= br_sha512_ID ; i++)
+    br_ssl_engine_set_hash(&sc->eng, i, hashes[i-1]) ;
+
+  br_ssl_engine_set_prf10(&sc->eng, &br_tls10_prf) ;
+  br_ssl_engine_set_prf_sha256(&sc->eng, &br_tls12_sha256_prf) ;
+  br_ssl_engine_set_prf_sha384(&sc->eng, &br_tls12_sha384_prf) ;
+
+  br_ssl_engine_set_default_aes_cbc(&sc->eng) ;
+  br_ssl_engine_set_default_aes_ccm(&sc->eng) ;
+  br_ssl_engine_set_default_aes_gcm(&sc->eng) ;
+  br_ssl_engine_set_default_des_cbc(&sc->eng) ;
+  br_ssl_engine_set_default_chapol(&sc->eng) ;
+}
diff --git a/src/sbearssl/sbearssl_sctx_set_policy_sni.c b/src/sbearssl/sbearssl_sctx_set_policy_sni.c
new file mode 100644
index 0000000..166cd97
--- /dev/null
+++ b/src/sbearssl/sbearssl_sctx_set_policy_sni.c
@@ -0,0 +1,11 @@
+/* ISC license. */
+
+#include <bearssl.h>
+
+#include <s6-networking/sbearssl.h>
+
+void sbearssl_sctx_set_policy_sni (br_ssl_server_context *sc, sbearssl_sni_policy_context *pol)
+{
+  sc->chain_handler.vtable = pol->vtable ;
+  sc->policy_vtable = &sc->chain_handler.vtable ;
+}
diff --git a/src/sbearssl/sbearssl_skey_storagelen.c b/src/sbearssl/sbearssl_skey_storagelen.c
new file mode 100644
index 0000000..706b5f6
--- /dev/null
+++ b/src/sbearssl/sbearssl_skey_storagelen.c
@@ -0,0 +1,16 @@
+/* ISC license. */
+
+#include <s6-networking/sbearssl.h>
+
+size_t sbearssl_skey_storagelen (sbearssl_skey const *l)
+{
+  switch (l->type)
+  {
+    case BR_KEYTYPE_RSA :
+      return l->data.rsa.plen + l->data.rsa.qlen + l->data.rsa.dplen + l->data.rsa.dqlen + l->data.rsa.iqlen ;
+    case BR_KEYTYPE_EC :
+      return l->data.ec.xlen ;
+    default :
+      return 0 ;
+  }
+}
diff --git a/src/sbearssl/sbearssl_skey_wipe.c b/src/sbearssl/sbearssl_skey_wipe.c
new file mode 100644
index 0000000..208f89f
--- /dev/null
+++ b/src/sbearssl/sbearssl_skey_wipe.c
@@ -0,0 +1,26 @@
+/* ISC license. */
+
+#include <bearssl.h>
+
+#include <skalibs/bytestr.h>
+
+#include <s6-networking/sbearssl.h>
+
+void sbearssl_skey_wipe (sbearssl_skey *key, char *s)
+{
+  switch (key->type)
+  {
+    case BR_KEYTYPE_RSA :
+      byte_zzero(s + key->rsa.p, key->rsa.plen) ;
+      byte_zzero(s + key->rsa.q, key->rsa.qlen) ;
+      byte_zzero(s + key->rsa.dp, key->rsa.dplen) ;
+      byte_zzero(s + key->rsa.dq, key->rsa.dqlen) ;
+      byte_zzero(s + key->rsa.iq, key->rsa.iqlen) ;
+      break ;
+    case BR_KEYTYPE_EC :
+      byte_zzero(s + key->ec.x, key->ec.xlen) ;
+      break ;
+    default : break ;
+  }
+  byte_zzero(key, sizeof(sbearssl_skey)) ;
+}
diff --git a/src/sbearssl/sbearssl_sni_policy_add_keypair_file.c b/src/sbearssl/sbearssl_sni_policy_add_keypair_file.c
new file mode 100644
index 0000000..e6cc974
--- /dev/null
+++ b/src/sbearssl/sbearssl_sni_policy_add_keypair_file.c
@@ -0,0 +1,42 @@
+/* ISC license. */
+
+#include <string.h>
+#include <errno.h>
+
+#include <bearssl.h>
+
+#include <skalibs/stralloc.h>
+#include <skalibs/genalloc.h>
+#include <skalibs/avltree.h>
+
+#include <s6-networking/sbearssl.h>
+#include "sbearssl-internal.h"
+
+int sbearssl_sni_policy_add_keypair_file (sbearssl_sni_policy_context *pol, char const *servername, char const *certfile, char const *keyfile)
+{
+  size_t sabase = pol->storage.len ;
+  size_t gabase = genalloc_len(sbearssl_cert, &pol->certga) ;
+  size_t mbase = genalloc_len(sbearssl_sni_policy_node, &pol->mapga) ;
+  sbearssl_sni_policy_node node = { .servername = sabase, .chainindex = gabase } ;
+
+  if (!stralloc_catb(&pol->storage, servername, strlen(servername) + 1)) return 0 ;
+  if (!sbearssl_cert_readbigpem(certfile, &pol->certga, &pol->storage)) goto err0 ;
+  node.chainlen = genalloc_len(sbearssl_cert, &pol->certga) - node.chainindex ;
+  if (!sbearssl_skey_readfile(keyfile, &node.skey, &pol->storage)) goto err1 ;
+  if (!genalloc_catb(sbearssl_sni_policy_node, &pol->mapga, &node, 1)) goto err2 ;
+  if (!avltree_insert(&pol->map, mbase)) goto err3 ;
+  return 1 ;
+
+ err3:
+  if (mbase) genalloc_setlen(sbearssl_sni_policy_node, &pol->mapga, mbase) ;
+  else genalloc_free(sbearssl_sni_policy_node, &pol->mapga) ;
+ err2:
+  sbearssl_skey_wipe(&pol->skey, pol->storage.s) ;
+ err1:
+  if (gabase) genalloc_setlen(sbearssl_cert, &pol->certga, gabase) ;
+  else genalloc_free(sbearssl_sni_policy_node, &pol->mapga) ;
+ err0:
+  if (sabase) pol->storage.len = sabase ;
+  else stralloc_free(pol->storage) ;
+  return 0 ;
+}
diff --git a/src/sbearssl/sbearssl_sni_policy_init.c b/src/sbearssl/sbearssl_sni_policy_init.c
new file mode 100644
index 0000000..fd0e946
--- /dev/null
+++ b/src/sbearssl/sbearssl_sni_policy_init.c
@@ -0,0 +1,75 @@
+/* ISC license. */
+
+#include <errno.h>
+
+#include <bearssl.h>
+
+#include <skalibs/stralloc.h>
+#include <skalibs/genalloc.h>
+#include <skalibs/avltree.h>
+
+#include <s6-networking/sbearssl.h>
+
+#define INSTANCE(c) ((sbearssl_sni_policy_context *)(c))
+
+static int choose (br_ssl_server_policy_class const **pctx, br_ssl_server_context const *sc, br_ssl_server_choices *choices)
+{
+  sbearssl_sni_policy_context *pol = INSTANCE(pctx) ;
+  uint32_t n ;
+  char const *servername = br_ssl_engine_get_server_name(&sc->eng) ;
+  if (!avltree_search(&pol->map, servername, &n)
+   && (!servername[0] || !avltree_search(&pol->map, "", &n)))
+    return 0 ;
+  avltree_free(&pol->map) ;
+  copy_and_free(pol, n) ;
+}
+
+static uint32_t do_keyx (br_ssl_server_policy_class const **pctx, unsigned char *data, size_t *len)
+{
+  sbearssl_sni_policy_context *pol = INSTANCE(pctx) ;
+  switch (pol->skey.type)
+  {
+    case BR_KEYTYPE_RSA : return kx_rsa(pol, data, len) ;
+    case BR_KEYTYPE_EC : return kx_ec(pol, data, len) ;
+    default : return 0 ;
+  }
+}
+
+static size_t do_sign (br_ssl_server_policy_class const **pctx, unsigned int algo_id, unsigned char *data, size_t hv_len, size_t len)
+{
+  sbearssl_sni_policy_context *pol = INSTANCE(pctx) ;
+  switch (pol->skey.type)
+  {
+    case BR_KEYTYPE_RSA : return sign_rsa(pol, algo_id, data, hv_len, len) ;
+    case BR_KEYTYPE_EC : return sign_ec(pol, algo_id, data, hv_len, len) ;
+    default : return 0 ;
+  }
+}
+
+static br_ssl_server_policy_class const vtable =
+{
+  .context_size = sizeof(sbearssl_sni_policy_context),
+  .choose = &choose,
+  .do_keyx = &do_keyx,
+  .do_sign = &do_sign
+} ;
+
+static void *sbearssl_sni_policy_node_dtok (uint32_t d, void *data)
+{
+  return ((sbearssl_sni_policy_context *)data)->storage.s + d ;
+}
+
+static int sbearssl_sni_policy_node_cmp (void const *a, void const *b, void *data)
+{
+  (void)data ;
+  return strcmp((char const *)a, (char const *)b) ;
+}
+
+void sbearssl_sni_policy_init (sbearssl_sni_policy_context *pol)
+{
+  pol->vtable = &vtable ;
+  pol->map = avltree_zero ;
+  pol->mapga = genalloc_zero ;
+  pol->certga = genalloc_zero ;
+  pol->storage = GENALLOC_ZERO ;
+}
diff --git a/src/sbearssl/sbearssl_sni_policy_vtable.c b/src/sbearssl/sbearssl_sni_policy_vtable.c
new file mode 100644
index 0000000..3b39055
--- /dev/null
+++ b/src/sbearssl/sbearssl_sni_policy_vtable.c
@@ -0,0 +1,71 @@
+/* ISC license. */
+
+#include <bearssl.h>
+
+#include <s6-networking/sbearssl.h>
+
+#define INSTANCE(c) ((sbearssl_x509_small_context *)(c))
+
+static void start_chain (br_x509_class const **c, char const *server_name)
+{
+  sbearssl_x509_small_context *ctx = INSTANCE(c) ;
+  ctx->minimal.vtable->start_chain(&ctx->minimal.vtable, server_name) ;
+
+  ctx->i = 0 ;
+}
+
+static void start_cert (br_x509_class const **c, uint32_t len)
+{
+  sbearssl_x509_small_context *ctx = INSTANCE(c) ;
+  ctx->minimal.vtable->start_cert(&ctx->minimal.vtable, len) ;
+
+  if (!ctx->i) br_sha256_init(&ctx->hashctx) ;
+}
+
+static void append (br_x509_class const **c, unsigned char const *s, size_t len)
+{
+  sbearssl_x509_small_context *ctx = INSTANCE(c) ;
+  ctx->minimal.vtable->append(&ctx->minimal.vtable, s, len) ;
+
+  if (!ctx->i) br_sha256_update(&ctx->hashctx, s, len) ;
+}
+
+static void end_cert (br_x509_class const **c)
+{
+  sbearssl_x509_small_context *ctx = INSTANCE(c) ;
+  ctx->minimal.vtable->end_cert(&ctx->minimal.vtable) ;
+
+  if (!ctx->i) br_sha256_out(&ctx->hashctx, ctx->eehash) ;
+  ctx->i++ ;
+}
+
+static unsigned int end_chain (br_x509_class const **c)
+{
+  sbearssl_x509_small_context *ctx = INSTANCE(c) ;
+  unsigned int r = ctx->minimal.vtable->end_chain(&ctx->minimal.vtable) ;
+  if (!r)
+  {
+    uint8_t mask = 1 ;
+    for (unsigned int i = 0 ; i < 6 ; i++, mask <<= 1)
+      if (ctx->elts[i].status)
+        *ctx->eltstatus |= ctx->elts[i].status < 0 ? 128 : mask ;
+  }
+  return r ;
+}
+
+static br_x509_pkey const *get_pkey(br_x509_class const *const *c, unsigned int *usages)
+{
+  sbearssl_x509_small_context *ctx = INSTANCE(c) ;
+  return ctx->minimal.vtable->get_pkey(&ctx->minimal.vtable, usages) ;
+}
+
+br_x509_class const sbearssl_x509_small_vtable =
+{
+  .context_size = sizeof(sbearssl_x509_small_context),
+  .start_chain = &start_chain,
+  .start_cert = &start_cert,
+  .append = &append,
+  .end_cert = &end_cert,
+  .end_chain = &end_chain,
+  .get_pkey = &get_pkey,
+} ;