GnuTLS: Fix client detection of server reject of client cert under TLS1.3

[exim.git] / src / src / tls-gnu.c

diff --git a/src/src/tls-gnu.c b/src/src/tls-gnu.c
index 3e7e8f9323fb358bdf30022f01c701ccf4c67215..de2d70c0990b8f76aa7e07470407a8ef6b799706 100644 (file)
--- a/src/src/tls-gnu.c
+++ b/src/src/tls-gnu.c
@@ -229,7 +229,7 @@ static gnutls_dh_params_t dh_server_params = NULL;
 
 static const int ssl_session_timeout = 200;
 
-static const char * const exim_default_gnutls_priority = "NORMAL";
+static const uschar * const exim_default_gnutls_priority = US"NORMAL";
 
 /* Guard library core initialisation */
 
@@ -787,9 +787,12 @@ if ((rc = gnutls_x509_crt_init(&cert))) goto err;
 where = US"generating pkey";
 if ((rc = gnutls_x509_privkey_generate(pkey, GNUTLS_PK_RSA,
 #ifdef SUPPORT_PARAM_TO_PK_BITS
-           gnutls_sec_param_to_pk_bits(GNUTLS_PK_RSA, GNUTLS_SEC_PARAM_LOW),
+# ifndef GNUTLS_SEC_PARAM_MEDIUM
+#  define GNUTLS_SEC_PARAM_MEDIUM GNUTLS_SEC_PARAM_HIGH
+# endif
+           gnutls_sec_param_to_pk_bits(GNUTLS_PK_RSA, GNUTLS_SEC_PARAM_MEDIUM),
 #else
-           1024,
+           2048,
 #endif
            0)))
   goto err;
@@ -1275,7 +1278,6 @@ int rc;
 size_t sz;
 const char *errpos;
 uschar *p;
-BOOL want_default_priorities;
 
 if (!exim_gnutls_base_init_done)
   {
@@ -1301,7 +1303,7 @@ if (!exim_gnutls_base_init_done)
   DEBUG(D_tls)
     {
     gnutls_global_set_log_function(exim_gnutls_logger_cb);
-    /* arbitrarily chosen level; bump upto 9 for more */
+    /* arbitrarily chosen level; bump up to 9 for more */
     gnutls_global_set_log_level(EXIM_GNUTLS_LIBRARY_LOG_LEVEL);
     }
 #endif
@@ -1384,32 +1386,24 @@ and replaces gnutls_require_kx, gnutls_require_mac & gnutls_require_protocols.
 This was backwards incompatible, but means Exim no longer needs to track
 all algorithms and provide string forms for them. */
 
-want_default_priorities = TRUE;
-
+p = NULL;
 if (state->tls_require_ciphers && *state->tls_require_ciphers)
   {
   if (!expand_check_tlsvar(tls_require_ciphers, errstr))
     return DEFER;
   if (state->exp_tls_require_ciphers && *state->exp_tls_require_ciphers)
     {
-    DEBUG(D_tls) debug_printf("GnuTLS session cipher/priority \"%s\"\n",
-        state->exp_tls_require_ciphers);
-
-    rc = gnutls_priority_init(&state->priority_cache,
-        CS state->exp_tls_require_ciphers, &errpos);
-    want_default_priorities = FALSE;
     p = state->exp_tls_require_ciphers;
+    DEBUG(D_tls) debug_printf("GnuTLS session cipher/priority \"%s\"\n", p);
     }
   }
-if (want_default_priorities)
+if (!p)
   {
+  p = exim_default_gnutls_priority;
   DEBUG(D_tls)
-    debug_printf("GnuTLS using default session cipher/priority \"%s\"\n",
-        exim_default_gnutls_priority);
-  rc = gnutls_priority_init(&state->priority_cache,
-      exim_default_gnutls_priority, &errpos);
-  p = US exim_default_gnutls_priority;
+    debug_printf("GnuTLS using default session cipher/priority \"%s\"\n", p);
   }
+rc = gnutls_priority_init(&state->priority_cache, CCS p, &errpos);
 
 exim_gnutls_err_check(rc, string_sprintf(
       "gnutls_priority_init(%s) failed at offset %ld, \"%.6s..\"",
@@ -2559,8 +2553,12 @@ DEBUG(D_tls) debug_printf("Calling gnutls_record_recv(%p, %p, %u)\n",
 
 sigalrm_seen = FALSE;
 if (smtp_receive_timeout > 0) ALARM(smtp_receive_timeout);
-inbytes = gnutls_record_recv(state->session, state->xfer_buffer,
-  MIN(ssl_xfer_buffer_size, lim));
+
+do
+  inbytes = gnutls_record_recv(state->session, state->xfer_buffer,
+    MIN(ssl_xfer_buffer_size, lim));
+while (inbytes == GNUTLS_E_AGAIN);
+
 if (smtp_receive_timeout > 0) ALARM_CLR(0);
 
 if (had_command_timeout)               /* set by signal handler */
@@ -2615,7 +2613,7 @@ else if (inbytes == 0)
 
 else if (inbytes < 0)
   {
-debug_printf("%s: err from gnutls_record_recv(\n", __FUNCTION__);
+  DEBUG(D_tls) debug_printf("%s: err from gnutls_record_recv(\n", __FUNCTION__);
   record_io_error(state, (int) inbytes, US"recv", NULL);
   state->xfer_error = TRUE;
   return FALSE;
@@ -2638,7 +2636,7 @@ Only used by the server-side TLS.
 
 This feeds DKIM and should be used for all message-body reads.
 
-Arguments:  lim                Maximum amount to read/bufffer
+Arguments:  lim                Maximum amount to read/buffer
 Returns:    the next character or EOF
 */
 
@@ -2737,17 +2735,20 @@ DEBUG(D_tls)
   debug_printf("Calling gnutls_record_recv(%p, %p, " SIZE_T_FMT ")\n",
       state->session, buff, len);
 
-inbytes = gnutls_record_recv(state->session, buff, len);
+do
+  inbytes = gnutls_record_recv(state->session, buff, len);
+while (inbytes == GNUTLS_E_AGAIN);
+
 if (inbytes > 0) return inbytes;
 if (inbytes == 0)
   {
   DEBUG(D_tls) debug_printf("Got TLS_EOF\n");
   }
 else
-{
-debug_printf("%s: err from gnutls_record_recv(\n", __FUNCTION__);
-record_io_error(state, (int)inbytes, US"recv", NULL);
-}
+  {
+  DEBUG(D_tls) debug_printf("%s: err from gnutls_record_recv(\n", __FUNCTION__);
+  record_io_error(state, (int)inbytes, US"recv", NULL);
+  }
 
 return -1;
 }
@@ -2789,7 +2790,10 @@ while (left > 0)
   {
   DEBUG(D_tls) debug_printf("gnutls_record_send(SSL, %p, " SIZE_T_FMT ")\n",
       buff, left);
-  outbytes = gnutls_record_send(state->session, buff, left);
+
+  do
+    outbytes = gnutls_record_send(state->session, buff, left);
+  while (outbytes == GNUTLS_E_AGAIN);
 
   DEBUG(D_tls) debug_printf("outbytes=" SSIZE_T_FMT "\n", outbytes);
   if (outbytes < 0)