Refactor tls code to support ucspi-tls

 That includes:
 - new architecture: the tls binary is now a child of the app
instead of the other way around
 - the sbearssl_run engine now takes a post-handshake callback.
This allows s6-tlsc and s6-tlsd to only exec into the app when
the handshake succeeds (which was already the case with libressl).
 - new binaries s6-tlsc-io and s6-tlsd-io encapsulate the crypto
code; they init and run the engine, connecting to 4 already open
fds (stdin/stdout = network, argv[1] and argv[2] = local)
 - s6-tlsc is now a simple wrapper around s6-tlsc-io
 - s6-tlsd is now a simple wrapper around s6-tlsd-io
 - new binary: s6-ucspitlsd, which is also a wrapper around
s6-tlsd-io, but differently: the parent execs the app which should
be ucspi-tls-aware, the child waits for a command from the parent
and execs into s6-tlsd-io if it receives it.

1 files changed, 49 insertions, 0 deletions

diff --git a/src/conn-tools/s6tls_exec_tlsdio.c b/src/conn-tools/s6tls_exec_tlsdio.c
new file mode 100644
index 0000000..b00adb2
--- /dev/null
+++ b/src/conn-tools/s6tls_exec_tlsdio.c
@@ -0,0 +1,49 @@
+/* ISC license. */
+
+#include <skalibs/posixplz.h>
+#include <skalibs/types.h>
+#include <skalibs/djbunix.h>
+
+#include <s6-networking/config.h>
+#include "s6tls-internal.h"
+
+void s6tls_exec_tlsdio (int const *fds, uint32_t options, unsigned int verbosity, unsigned int kimeout)
+{
+  char const *newargv[13] ;
+  unsigned int m = 0 ;
+  char fmtv[UINT_FMT] ;
+  char fmtd[UINT_FMT] ;
+  char fmtk[UINT_FMT] ;
+  char fmtr[UINT_FMT] ;
+  char fmtw[UINT_FMT] ;
+
+  newargv[m++] = S6_NETWORKING_BINPREFIX "s6-tlsd-io" ;
+  if (verbosity != 1)
+  {
+    newargv[m++] = "-v" ;
+    newargv[m++] = fmtv ;
+    fmtv[uint_fmt(fmtv, verbosity)] = 0 ;
+  }
+  if (fds[2])
+  {
+    newargv[m++] = "-d" ;
+    newargv[m++] = fmtd ;
+    fmtd[uint_fmt(fmtd, fds[2])] = 0 ;
+  }
+  newargv[m++] = options & 4 ? "-S" : "-s" ;
+  if (options & 1)
+    newargv[m++] = options & 2 ? "-y" : "-Y" ;
+  if (kimeout)
+  {
+    newargv[m++] = "-K" ;
+    newargv[m++] = fmtk ;
+    fmtk[uint_fmt(fmtk, kimeout)] = 0 ;
+  }
+  newargv[m++] = "--" ;
+  newargv[m++] = fmtr ;
+  fmtr[uint_fmt(fmtr, fds[0])] = 0 ;
+  newargv[m++] = fmtw ;
+  fmtw[uint_fmt(fmtw, fds[1])] = 0 ;
+  newargv[m++] = 0 ;
+  xpathexec_run(newargv[0], newargv, (char const *const *)environ) ;
+}