X-Git-Url: https://git.exim.org/exim.git/blobdiff_plain/ef57b25bfa7623c3f8a8e65f927165c4ddc7c43b..HEAD:/src/src/tls.c

diff --git a/src/src/tls.c b/src/src/tls.c
index 76e72b5f5..a1ae1abd1 100644
--- a/src/src/tls.c
+++ b/src/src/tls.c
@@ -2,9 +2,10 @@
 *     Exim - an Internet mail transport agent    *
 *************************************************/
 
-/* Copyright (c) The Exim Maintainers 2020 - 2022 */
+/* Copyright (c) The Exim Maintainers 2020 - 2024 */
 /* Copyright (c) University of Cambridge 1995 - 2018 */
 /* See the file NOTICE for conditions of use and distribution. */
+/* SPDX-License-Identifier: GPL-2.0-or-later */
 
 /* This module provides TLS (aka SSL) support for Exim. The code for OpenSSL is
 based on a patch that was originally contributed by Steve Haslam. It was
@@ -25,11 +26,6 @@ functions from the OpenSSL or GNU TLS libraries. */
 #endif
 
 
-/* Forward decl. */
-static void tls_client_resmption_key(tls_support *, smtp_connect_args *,
-  smtp_transport_options_block *);
-
-
 #if defined(MACRO_PREDEF) && !defined(DISABLE_TLS)
 # include "macro_predef.h"
 # ifdef USE_GNUTLS
@@ -44,13 +40,16 @@ static void tls_client_resmption_key(tls_support *, smtp_connect_args *,
 static void tls_per_lib_daemon_init(void);
 static void tls_per_lib_daemon_tick(void);
 static unsigned  tls_server_creds_init(void);
-static void tls_server_creds_invalidate(void);
 static void tls_client_creds_init(transport_instance *, BOOL);
-static void tls_client_creds_invalidate(transport_instance *);
 static void tls_daemon_creds_reload(void);
 static BOOL opt_set_and_noexpand(const uschar *);
 static BOOL opt_unset_or_noexpand(const uschar *);
 
+#if defined(EXIM_HAVE_INOTIFY) || defined(EXIM_HAVE_KEVENT)
+static void tls_server_creds_invalidate(void);
+static void tls_client_creds_invalidate(transport_instance *);
+#endif
+
 
 
 /* This module is compiled only when it is specifically requested in the
@@ -105,10 +104,14 @@ Returns:    TRUE if OK; result may still be NULL after forced failure
 */
 
 static BOOL
-expand_check(const uschar *s, const uschar *name, uschar **result, uschar ** errstr)
+expand_check(const uschar * s, const uschar * name,
+  uschar ** result, uschar ** errstr)
 {
 if (!s)
+  {
+  f.expand_string_forcedfail = FALSE;
   *result = NULL;
+  }
 else if (  !(*result = expand_string(US s)) /* need to clean up const more */
 	&& !f.expand_string_forcedfail
 	)
@@ -156,7 +159,7 @@ for (unsigned loop = 20;
   if (--loop == 0) { errno = ELOOP; return FALSE; }
   filename = buf[0] == '/'
     ? string_copyn(buf, (unsigned)len)	/* mem released by tls_set_watch */
-    : string_sprintf("%.*s/%.*s", (int)(s - filename), (int)len);
+    : string_sprintf("%.*s/%.*s", (int)(s - filename), filename, (int)len, buf);
   s = Ustrrchr(filename, '/');
   }
 if (errno != EINVAL)
@@ -324,7 +327,9 @@ tls_client_creds_reload(BOOL watch)
 for(transport_instance * t = transports; t; t = t->next)
   if (Ustrcmp(t->driver_name, "smtp") == 0)
     {
+#if defined(EXIM_HAVE_INOTIFY) || defined(EXIM_HAVE_KEVENT)
     tls_client_creds_invalidate(t);
+#endif
     tls_client_creds_init(t, watch);
     }
 }
@@ -360,7 +365,11 @@ unsigned lifetime;
 tls_watch_invalidate();
 #endif
 
+#if defined(EXIM_HAVE_INOTIFY) || defined(EXIM_HAVE_KEVENT)
 tls_server_creds_invalidate();
+#endif
+
+/* _expire is for a time-limited selfsign server cert */
 tls_creds_expire = (lifetime = tls_server_creds_init())
   ? time(NULL) + lifetime : 0;
 
@@ -455,6 +464,10 @@ tzset();
 /*************************************************
 *        Many functions are package-specific     *
 *************************************************/
+/* Forward decl. */
+static void tls_client_resmption_key(tls_support *, smtp_connect_args *,
+  smtp_transport_options_block *);
+
 
 #ifdef USE_GNUTLS
 # include "tls-gnu.c"
@@ -667,21 +680,24 @@ Returns:
 BOOL
 tls_is_name_for_cert(const uschar * namelist, void * cert)
 {
-uschar * altnames = tls_cert_subject_altname(cert, US"dns");
-uschar * subjdn;
-uschar * certname;
+uschar * altnames, * subjdn, * certname, * cmpname;
 int cmp_sep = 0;
-uschar * cmpname;
 
 if ((altnames = tls_cert_subject_altname(cert, US"dns")))
   {
   int alt_sep = '\n';
+  DEBUG(D_tls|D_lookup) debug_printf_indent("cert has SAN\n");
   while ((cmpname = string_nextinlist(&namelist, &cmp_sep, NULL, 0)))
     {
     const uschar * an = altnames;
+    DEBUG(D_tls|D_lookup) debug_printf_indent(" %s in SANs?", cmpname);
     while ((certname = string_nextinlist(&an, &alt_sep, NULL, 0)))
       if (is_name_match(cmpname, certname))
+	{
+	DEBUG(D_tls|D_lookup) debug_printf_indent("  yes (matched %s)\n", certname);
 	return TRUE;
+	}
+    DEBUG(D_tls|D_lookup) debug_printf_indent(" no (end of SAN list)\n");
     }
   }
 
@@ -693,13 +709,18 @@ else if ((subjdn = tls_cert_subject(cert, NULL)))
   while ((cmpname = string_nextinlist(&namelist, &cmp_sep, NULL, 0)))
     {
     const uschar * sn = subjdn;
+    DEBUG(D_tls|D_lookup) debug_printf_indent(" %s in SN?", cmpname);
     while ((certname = string_nextinlist(&sn, &sn_sep, NULL, 0)))
       if (  *certname++ == 'C'
 	 && *certname++ == 'N'
 	 && *certname++ == '='
 	 && is_name_match(cmpname, certname)
 	 )
+	{
+	DEBUG(D_tls|D_lookup) debug_printf_indent("  yes (matched %s)\n", certname);
 	return TRUE;
+	}
+    DEBUG(D_tls|D_lookup) debug_printf_indent(" no (end of CN)\n");
     }
   }
 return FALSE;
@@ -849,6 +870,57 @@ DEBUG(D_tls) debug_printf("TLS: resume session index %s\n", tlsp->resume_index);
 #endif
 }
 
+
+
+/* Start TLS as a client for an ajunct connection, eg. readsocket
+Return boolean success.
+*/
+
+BOOL
+tls_client_adjunct_start(host_item * host, client_conn_ctx * cctx,
+  const uschar * sni, uschar ** errmsg)
+{
+union sockaddr_46 interface_sock;
+EXIM_SOCKLEN_T size = sizeof(interface_sock);
+smtp_connect_args conn_args = {.host = host };
+tls_support tls_dummy = { .sni = NULL };
+uschar * errstr;
+
+if (getsockname(cctx->sock, (struct sockaddr *) &interface_sock, &size) == 0)
+  conn_args.sending_ip_address = host_ntoa(-1, &interface_sock, NULL, NULL);
+else
+  {
+  *errmsg = string_sprintf("getsockname failed: %s", strerror(errno));
+  return FALSE;
+  }
+
+/* To handle SNI we need to emulate more of a real transport because the
+base tls code assumes that is where the SNI string lives. */
+
+if (*sni)
+  {
+  transport_instance * tb;
+  smtp_transport_options_block * ob;
+
+  conn_args.tblock = tb = store_get(sizeof(*tb), GET_UNTAINTED);
+  memset(tb, 0, sizeof(*tb));
+
+  tb->options_block = ob = store_get(sizeof(*ob), GET_UNTAINTED);
+  memcpy(ob, &smtp_transport_option_defaults, sizeof(*ob));
+
+  ob->tls_sni = sni;
+  }
+
+if (!tls_client_start(cctx, &conn_args, NULL, &tls_dummy, &errstr))
+  {
+  *errmsg = string_sprintf("TLS connect failed: %s", errstr);
+  return FALSE;
+  }
+return TRUE;
+}
+
+
+
 #endif	/*!DISABLE_TLS*/
 #endif	/*!MACRO_PREDEF*/