Fix mariadb/mysql macro confusion

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

diff --git a/src/src/tls-gnu.c b/src/src/tls-gnu.c
index 3c926c0d4ab3f515a1aa13ffb647d5838a7439ce..d54c560f708ee9d4d6fd0458a9ee10c2c71a52a3 100644 (file)
--- a/src/src/tls-gnu.c
+++ b/src/src/tls-gnu.c
@@ -2,7 +2,7 @@
 *     Exim - an Internet mail transport agent    *
 *************************************************/
 
 *     Exim - an Internet mail transport agent    *
 *************************************************/
 

-/* Copyright (c) University of Cambridge 1995 - 2014 */
+/* Copyright (c) University of Cambridge 1995 - 2015 */

 /* See the file NOTICE for conditions of use and distribution. */
 
 /* Copyright (c) Phil Pennock 2012 */
 /* See the file NOTICE for conditions of use and distribution. */
 
 /* Copyright (c) Phil Pennock 2012 */


@@ -13,7 +13,7 @@ tls.c when USE_GNUTLS has been set.
 
 The code herein is a revamp of GnuTLS integration using the current APIs; the
 original tls-gnu.c was based on a patch which was contributed by Nikos
 
 The code herein is a revamp of GnuTLS integration using the current APIs; the
 original tls-gnu.c was based on a patch which was contributed by Nikos

-Mavroyanopoulos.  The revamp is partially a rewrite, partially cut&paste as
+Mavrogiannopoulos.  The revamp is partially a rewrite, partially cut&paste as

 appropriate.
 
 APIs current as of GnuTLS 2.12.18; note that the GnuTLS manual is for GnuTLS 3,
 appropriate.
 
 APIs current as of GnuTLS 2.12.18; note that the GnuTLS manual is for GnuTLS 3,


@@ -42,8 +42,29 @@ require current GnuTLS, then we'll drop support for the ancient libraries).
 /* needed to disable PKCS11 autoload unless requested */
 #if GNUTLS_VERSION_NUMBER >= 0x020c00
 # include <gnutls/pkcs11.h>
 /* needed to disable PKCS11 autoload unless requested */
 #if GNUTLS_VERSION_NUMBER >= 0x020c00
 # include <gnutls/pkcs11.h>

+# define SUPPORT_PARAM_TO_PK_BITS

 #endif
 #endif

-#ifdef EXPERIMENTAL_OCSP
+#if GNUTLS_VERSION_NUMBER < 0x030103 && !defined(DISABLE_OCSP)
+# warning "GnuTLS library version too old; define DISABLE_OCSP in Makefile"
+# define DISABLE_OCSP
+#endif
+#if GNUTLS_VERSION_NUMBER < 0x020a00 && !defined(DISABLE_EVENT)
+# warning "GnuTLS library version too old; tls:cert event unsupported"
+# define DISABLE_EVENT
+#endif
+#if GNUTLS_VERSION_NUMBER >= 0x030306
+# define SUPPORT_CA_DIR
+#else
+# undef  SUPPORT_CA_DIR
+#endif
+#if GNUTLS_VERSION_NUMBER >= 0x030014
+# define SUPPORT_SYSDEFAULT_CABUNDLE
+#endif
+#if GNUTLS_VERSION_NUMBER >= 0x030109
+# define SUPPORT_CORK
+#endif
+
+#ifndef DISABLE_OCSP

 # include <gnutls/ocsp.h>
 #endif
 
 # include <gnutls/ocsp.h>
 #endif
 


@@ -60,7 +81,8 @@ Changes:
 
 /* Values for verify_requirement */
 
 
 /* Values for verify_requirement */
 

-enum peer_verify_requirement { VERIFY_NONE, VERIFY_OPTIONAL, VERIFY_REQUIRED };
+enum peer_verify_requirement
+  { VERIFY_NONE, VERIFY_OPTIONAL, VERIFY_REQUIRED };

 
 /* This holds most state for server or client; with this, we can set up an
 outbound TLS-enabled connection in an ACL callout, while not stomping all
 
 /* This holds most state for server or client; with this, we can set up an
 outbound TLS-enabled connection in an ACL callout, while not stomping all


@@ -95,13 +117,17 @@ typedef struct exim_gnutls_state {
   const uschar *tls_verify_certificates;
   const uschar *tls_crl;
   const uschar *tls_require_ciphers;
   const uschar *tls_verify_certificates;
   const uschar *tls_crl;
   const uschar *tls_require_ciphers;

+

   uschar *exp_tls_certificate;
   uschar *exp_tls_privatekey;
   uschar *exp_tls_certificate;
   uschar *exp_tls_privatekey;

-  uschar *exp_tls_sni;

   uschar *exp_tls_verify_certificates;
   uschar *exp_tls_crl;
   uschar *exp_tls_require_ciphers;
   uschar *exp_tls_ocsp_file;
   uschar *exp_tls_verify_certificates;
   uschar *exp_tls_crl;
   uschar *exp_tls_require_ciphers;
   uschar *exp_tls_ocsp_file;

+  const uschar *exp_tls_verify_cert_hostnames;
+#ifndef DISABLE_EVENT
+  uschar *event_action;
+#endif

 
   tls_support *tlsp;   /* set in tls_init() */
 
 
   tls_support *tlsp;   /* set in tls_init() */
 


@@ -113,12 +139,45 @@ typedef struct exim_gnutls_state {
 } exim_gnutls_state_st;
 
 static const exim_gnutls_state_st exim_gnutls_state_init = {
 } exim_gnutls_state_st;
 
 static const exim_gnutls_state_st exim_gnutls_state_init = {

-  NULL, NULL, NULL, VERIFY_NONE, -1, -1, FALSE, FALSE, FALSE,
-  NULL, NULL, NULL, NULL,
-  NULL, NULL, NULL, NULL, NULL, NULL,
-  NULL, NULL, NULL, NULL, NULL, NULL, NULL,
-  NULL,
-  NULL, 0, 0, 0, 0,
+  .session =           NULL,
+  .x509_cred =         NULL,
+  .priority_cache =    NULL,
+  .verify_requirement =        VERIFY_NONE,
+  .fd_in =             -1,
+  .fd_out =            -1,
+  .peer_cert_verified =        FALSE,
+  .trigger_sni_changes =FALSE,
+  .have_set_peerdn =   FALSE,
+  .host =              NULL,
+  .peercert =          NULL,
+  .peerdn =            NULL,
+  .ciphersuite =       NULL,
+  .received_sni =      NULL,
+
+  .tls_certificate =   NULL,
+  .tls_privatekey =    NULL,
+  .tls_sni =           NULL,
+  .tls_verify_certificates = NULL,
+  .tls_crl =           NULL,
+  .tls_require_ciphers =NULL,
+
+  .exp_tls_certificate = NULL,
+  .exp_tls_privatekey =        NULL,
+  .exp_tls_verify_certificates = NULL,
+  .exp_tls_crl =       NULL,
+  .exp_tls_require_ciphers = NULL,
+  .exp_tls_ocsp_file = NULL,
+  .exp_tls_verify_cert_hostnames = NULL,
+#ifndef DISABLE_EVENT
+  .event_action =      NULL,
+#endif
+  .tlsp =              NULL,
+
+  .xfer_buffer =       NULL,
+  .xfer_buffer_lwm =   0,
+  .xfer_buffer_hwm =   0,
+  .xfer_eof =          0,
+  .xfer_error =                0,

 };
 
 /* Not only do we have our own APIs which don't pass around state, assuming
 };
 
 /* Not only do we have our own APIs which don't pass around state, assuming


@@ -128,7 +187,9 @@ context we're currently dealing with" pointer and rely upon being
 single-threaded to keep from processing data on an inbound TLS connection while
 talking to another TLS connection for an outbound check.  This does mean that
 there's no way for heart-beats to be responded to, for the duration of the
 single-threaded to keep from processing data on an inbound TLS connection while
 talking to another TLS connection for an outbound check.  This does mean that
 there's no way for heart-beats to be responded to, for the duration of the

-second connection. */
+second connection.
+XXX But see gnutls_session_get_ptr()
+*/

 
 static exim_gnutls_state_st state_server, state_client;
 
 
 static exim_gnutls_state_st state_server, state_client;
 


@@ -148,6 +209,10 @@ static const char * const exim_default_gnutls_priority = "NORMAL";
 
 static BOOL exim_gnutls_base_init_done = FALSE;
 
 
 static BOOL exim_gnutls_base_init_done = FALSE;
 

+#ifndef DISABLE_OCSP
+static BOOL gnutls_buggy_ocsp = FALSE;
+#endif
+

 
 /* ------------------------------------------------------------------------ */
 /* macros */
 
 /* ------------------------------------------------------------------------ */
 /* macros */


@@ -158,38 +223,41 @@ static BOOL exim_gnutls_base_init_done = FALSE;
 the library logging; a value less than 0 disables the calls to set up logging
 callbacks. */
 #ifndef EXIM_GNUTLS_LIBRARY_LOG_LEVEL
 the library logging; a value less than 0 disables the calls to set up logging
 callbacks. */
 #ifndef EXIM_GNUTLS_LIBRARY_LOG_LEVEL

-#define EXIM_GNUTLS_LIBRARY_LOG_LEVEL -1
+# define EXIM_GNUTLS_LIBRARY_LOG_LEVEL -1

 #endif
 
 #ifndef EXIM_CLIENT_DH_MIN_BITS
 #endif
 
 #ifndef EXIM_CLIENT_DH_MIN_BITS

-#define EXIM_CLIENT_DH_MIN_BITS 1024
+# define EXIM_CLIENT_DH_MIN_BITS 1024

 #endif
 
 /* With GnuTLS 2.12.x+ we have gnutls_sec_param_to_pk_bits() with which we
 can ask for a bit-strength.  Without that, we stick to the constant we had
 before, for now. */
 #ifndef EXIM_SERVER_DH_BITS_PRE2_12
 #endif
 
 /* With GnuTLS 2.12.x+ we have gnutls_sec_param_to_pk_bits() with which we
 can ask for a bit-strength.  Without that, we stick to the constant we had
 before, for now. */
 #ifndef EXIM_SERVER_DH_BITS_PRE2_12

-#define EXIM_SERVER_DH_BITS_PRE2_12 1024
+# define EXIM_SERVER_DH_BITS_PRE2_12 1024

 #endif
 
 #define exim_gnutls_err_check(Label) do { \
 #endif
 
 #define exim_gnutls_err_check(Label) do { \

-  if (rc != GNUTLS_E_SUCCESS) { return tls_error((Label), gnutls_strerror(rc), host); } } while (0)
+  if (rc != GNUTLS_E_SUCCESS) \
+    return tls_error((Label), gnutls_strerror(rc), host, errstr); \
+  } while (0)

 
 

-#define expand_check_tlsvar(Varname) expand_check(state->Varname, US #Varname, &state->exp_##Varname)
+#define expand_check_tlsvar(Varname, errstr) \
+  expand_check(state->Varname, US #Varname, &state->exp_##Varname, errstr)

 
 #if GNUTLS_VERSION_NUMBER >= 0x020c00
 
 #if GNUTLS_VERSION_NUMBER >= 0x020c00

-#define HAVE_GNUTLS_SESSION_CHANNEL_BINDING
-#define HAVE_GNUTLS_SEC_PARAM_CONSTANTS
-#define HAVE_GNUTLS_RND
+# define HAVE_GNUTLS_SESSION_CHANNEL_BINDING
+# define HAVE_GNUTLS_SEC_PARAM_CONSTANTS
+# define HAVE_GNUTLS_RND

 /* The security fix we provide with the gnutls_allow_auto_pkcs11 option
  * (4.82 PP/09) introduces a compatibility regression. The symbol simply
  * isn't available sometimes, so this needs to become a conditional
  * compilation; the sanest way to deal with this being a problem on
  * older OSes is to block it in the Local/Makefile with this compiler
  * definition  */
 /* The security fix we provide with the gnutls_allow_auto_pkcs11 option
  * (4.82 PP/09) introduces a compatibility regression. The symbol simply
  * isn't available sometimes, so this needs to become a conditional
  * compilation; the sanest way to deal with this being a problem on
  * older OSes is to block it in the Local/Makefile with this compiler
  * definition  */

-#ifndef AVOID_GNUTLS_PKCS11
-#define HAVE_GNUTLS_PKCS11
-#endif /* AVOID_GNUTLS_PKCS11 */
+# ifndef AVOID_GNUTLS_PKCS11
+#  define HAVE_GNUTLS_PKCS11
+# endif /* AVOID_GNUTLS_PKCS11 */

 #endif
 
 
 #endif
 
 


@@ -204,7 +272,7 @@ static void exim_gnutls_logger_cb(int level, const char *message);
 
 static int exim_sni_handling_cb(gnutls_session_t session);
 
 
 static int exim_sni_handling_cb(gnutls_session_t session);
 

-#ifdef EXPERIMENTAL_OCSP
+#ifndef DISABLE_OCSP

 static int server_ocsp_stapling_cb(gnutls_session_t session, void * ptr,
   gnutls_datum_t * ocsp_response);
 #endif
 static int server_ocsp_stapling_cb(gnutls_session_t session, void * ptr,
   gnutls_datum_t * ocsp_response);
 #endif


@@ -231,28 +299,18 @@ Argument:
             usually obtained from gnutls_strerror()
   host      NULL if setting up a server;
             the connected host if setting up a client
             usually obtained from gnutls_strerror()
   host      NULL if setting up a server;
             the connected host if setting up a client

+  errstr    pointer to returned error string

 
 Returns:    OK/DEFER/FAIL
 */
 
 static int
 
 Returns:    OK/DEFER/FAIL
 */
 
 static int

-tls_error(const uschar *prefix, const char *msg, const host_item *host)
+tls_error(const uschar *prefix, const char *msg, const host_item *host,
+  uschar ** errstr)

 {
 {

-if (host)
-  {
-  log_write(0, LOG_MAIN, "TLS error on connection to %s [%s] (%s)%s%s",
-      host->name, host->address, prefix, msg ? ": " : "", msg ? msg : "");
-  return FAIL;
-  }
-else
-  {
-  uschar *conn_info = smtp_get_connection_info();
-  if (Ustrncmp(conn_info, US"SMTP ", 5) == 0)
-    conn_info += 5;
-  log_write(0, LOG_MAIN, "TLS error on %s (%s)%s%s",
-      conn_info, prefix, msg ? ": " : "", msg ? msg : "");
-  return DEFER;
-  }
+if (errstr)
+  *errstr = string_sprintf("(%s)%s%s", prefix, msg ? ": " : "", msg ? msg : "");
+return host ? FAIL : DEFER;

 }
 
 
 }
 
 


@@ -276,7 +334,8 @@ Returns:   nothing
 static void
 record_io_error(exim_gnutls_state_st *state, int rc, uschar *when, uschar *text)
 {
 static void
 record_io_error(exim_gnutls_state_st *state, int rc, uschar *when, uschar *text)
 {

-const char *msg;
+const char * msg;
+uschar * errstr;

 
 if (rc == GNUTLS_E_FATAL_ALERT_RECEIVED)
   msg = CS string_sprintf("%s: %s", US gnutls_strerror(rc),
 
 if (rc == GNUTLS_E_FATAL_ALERT_RECEIVED)
   msg = CS string_sprintf("%s: %s", US gnutls_strerror(rc),


@@ -284,7 +343,18 @@ if (rc == GNUTLS_E_FATAL_ALERT_RECEIVED)
 else
   msg = gnutls_strerror(rc);
 
 else
   msg = gnutls_strerror(rc);
 

-tls_error(when, msg, state->host);
+(void) tls_error(when, msg, state->host, &errstr);
+
+if (state->host)
+  log_write(0, LOG_MAIN, "H=%s [%s] TLS error on connection %s",
+    state->host->name, state->host->address, errstr);
+else
+  {
+  uschar * conn_info = smtp_get_connection_info();
+  if (Ustrncmp(conn_info, US"SMTP ", 5) == 0) conn_info += 5;
+  /* I'd like to get separated H= here, but too hard for now */
+  log_write(0, LOG_MAIN, "TLS error on %s %s", conn_info, errstr);
+  }

 }
 
 
 }
 
 


@@ -294,13 +364,19 @@ tls_error(when, msg, state->host);
 *        Set various Exim expansion vars         *
 *************************************************/
 
 *        Set various Exim expansion vars         *
 *************************************************/
 

-#define exim_gnutls_cert_err(Label) do { \
-  if (rc != GNUTLS_E_SUCCESS) { \
-    DEBUG(D_tls) debug_printf("TLS: cert problem: %s: %s\n", (Label), gnutls_strerror(rc)); \
-    return rc; } } while (0)
+#define exim_gnutls_cert_err(Label) \
+  do \
+    { \
+    if (rc != GNUTLS_E_SUCCESS) \
+      { \
+      DEBUG(D_tls) debug_printf("TLS: cert problem: %s: %s\n", \
+       (Label), gnutls_strerror(rc)); \
+      return rc; \
+      } \
+    } while (0)

 
 static int
 
 static int

-import_cert(const gnutls_datum * cert, gnutls_x509_crt_t * crtp)
+import_cert(const gnutls_datum_t * cert, gnutls_x509_crt_t * crtp)

 {
 int rc;
 
 {
 int rc;
 


@@ -374,7 +450,7 @@ if (rc) {
 } else {
   old_pool = store_pool;
   store_pool = POOL_PERM;
 } else {
   old_pool = store_pool;
   store_pool = POOL_PERM;

-  tls_channelbinding_b64 = auth_b64encode(channel.data, (int)channel.size);
+  tls_channelbinding_b64 = b64encode(channel.data, (int)channel.size);

   store_pool = old_pool;
   DEBUG(D_tls) debug_printf("Have channel bindings cached for possible auth usage.\n");
 }
   store_pool = old_pool;
   DEBUG(D_tls) debug_printf("Have channel bindings cached for possible auth usage.\n");
 }


@@ -386,7 +462,7 @@ tlsp->sni =    state->received_sni;
 
 /* record our certificate */
   {
 
 /* record our certificate */
   {

-  const gnutls_datum * cert = gnutls_certificate_get_ours(state->session);
+  const gnutls_datum_t * cert = gnutls_certificate_get_ours(state->session);

   gnutls_x509_crt_t crt;
 
   tlsp->ourcert = cert && import_cert(cert, &crt)==0 ? crt : NULL;
   gnutls_x509_crt_t crt;
 
   tlsp->ourcert = cert && import_cert(cert, &crt)==0 ? crt : NULL;


@@ -414,11 +490,11 @@ Returns:     OK/DEFER/FAIL
 */
 
 static int
 */
 
 static int

-init_server_dh(void)
+init_server_dh(uschar ** errstr)

 {
 int fd, rc;
 unsigned int dh_bits;
 {
 int fd, rc;
 unsigned int dh_bits;

-gnutls_datum m;
+gnutls_datum_t m;

 uschar filename_buf[PATH_MAX];
 uschar *filename = NULL;
 size_t sz;
 uschar filename_buf[PATH_MAX];
 uschar *filename = NULL;
 size_t sz;


@@ -435,7 +511,7 @@ exim_gnutls_err_check(US"gnutls_dh_params_init");
 m.data = NULL;
 m.size = 0;
 
 m.data = NULL;
 m.size = 0;
 

-if (!expand_check(tls_dhparam, US"tls_dhparam", &exp_tls_dhparam))
+if (!expand_check(tls_dhparam, US"tls_dhparam", &exp_tls_dhparam, errstr))

   return DEFER;
 
 if (!exp_tls_dhparam)
   return DEFER;
 
 if (!exp_tls_dhparam)


@@ -453,9 +529,8 @@ else if (Ustrcmp(exp_tls_dhparam, "none") == 0)
   }
 else if (exp_tls_dhparam[0] != '/')
   {
   }
 else if (exp_tls_dhparam[0] != '/')
   {

-  m.data = US std_dh_prime_named(exp_tls_dhparam);
-  if (m.data == NULL)
-    return tls_error(US"No standard prime named", CS exp_tls_dhparam, NULL);
+  if (!(m.data = US std_dh_prime_named(exp_tls_dhparam)))
+    return tls_error(US"No standard prime named", CS exp_tls_dhparam, NULL, errstr);

   m.size = Ustrlen(m.data);
   }
 else
   m.size = Ustrlen(m.data);
   }
 else


@@ -477,7 +552,7 @@ if (m.data)
 different filename and ensure we have sufficient bits. */
 dh_bits = gnutls_sec_param_to_pk_bits(GNUTLS_PK_DH, GNUTLS_SEC_PARAM_NORMAL);
 if (!dh_bits)
 different filename and ensure we have sufficient bits. */
 dh_bits = gnutls_sec_param_to_pk_bits(GNUTLS_PK_DH, GNUTLS_SEC_PARAM_NORMAL);
 if (!dh_bits)

-  return tls_error(US"gnutls_sec_param_to_pk_bits() failed", NULL, NULL);
+  return tls_error(US"gnutls_sec_param_to_pk_bits() failed", NULL, NULL, errstr);

 DEBUG(D_tls)
   debug_printf("GnuTLS tells us that for D-H PK, NORMAL is %d bits.\n",
       dh_bits);
 DEBUG(D_tls)
   debug_printf("GnuTLS tells us that for D-H PK, NORMAL is %d bits.\n",
       dh_bits);


@@ -501,15 +576,14 @@ if (use_file_in_spool)
   {
   if (!string_format(filename_buf, sizeof(filename_buf),
         "%s/gnutls-params-%d", spool_directory, dh_bits))
   {
   if (!string_format(filename_buf, sizeof(filename_buf),
         "%s/gnutls-params-%d", spool_directory, dh_bits))

-    return tls_error(US"overlong filename", NULL, NULL);
+    return tls_error(US"overlong filename", NULL, NULL, errstr);

   filename = filename_buf;
   }
 
 /* Open the cache file for reading and if successful, read it and set up the
 parameters. */
 
   filename = filename_buf;
   }
 
 /* Open the cache file for reading and if successful, read it and set up the
 parameters. */
 

-fd = Uopen(filename, O_RDONLY, 0);
-if (fd >= 0)
+if ((fd = Uopen(filename, O_RDONLY, 0)) >= 0)

   {
   struct stat statbuf;
   FILE *fp;
   {
   struct stat statbuf;
   FILE *fp;


@@ -519,36 +593,33 @@ if (fd >= 0)
     {
     saved_errno = errno;
     (void)close(fd);
     {
     saved_errno = errno;
     (void)close(fd);

-    return tls_error(US"TLS cache stat failed", strerror(saved_errno), NULL);
+    return tls_error(US"TLS cache stat failed", strerror(saved_errno), NULL, errstr);

     }
   if (!S_ISREG(statbuf.st_mode))
     {
     (void)close(fd);
     }
   if (!S_ISREG(statbuf.st_mode))
     {
     (void)close(fd);

-    return tls_error(US"TLS cache not a file", NULL, NULL);
+    return tls_error(US"TLS cache not a file", NULL, NULL, errstr);

     }
     }

-  fp = fdopen(fd, "rb");
-  if (!fp)
+  if (!(fp = fdopen(fd, "rb")))

     {
     saved_errno = errno;
     (void)close(fd);
     return tls_error(US"fdopen(TLS cache stat fd) failed",
     {
     saved_errno = errno;
     (void)close(fd);
     return tls_error(US"fdopen(TLS cache stat fd) failed",

-        strerror(saved_errno), NULL);
+        strerror(saved_errno), NULL, errstr);

     }
 
   m.size = statbuf.st_size;
     }
 
   m.size = statbuf.st_size;

-  m.data = malloc(m.size);
-  if (m.data == NULL)
+  if (!(m.data = malloc(m.size)))

     {
     fclose(fp);
     {
     fclose(fp);

-    return tls_error(US"malloc failed", strerror(errno), NULL);
+    return tls_error(US"malloc failed", strerror(errno), NULL, errstr);

     }
     }

-  sz = fread(m.data, m.size, 1, fp);
-  if (!sz)
+  if (!(sz = fread(m.data, m.size, 1, fp)))

     {
     saved_errno = errno;
     fclose(fp);
     free(m.data);
     {
     saved_errno = errno;
     fclose(fp);
     free(m.data);

-    return tls_error(US"fread failed", strerror(saved_errno), NULL);
+    return tls_error(US"fread failed", strerror(saved_errno), NULL, errstr);

     }
   fclose(fp);
 
     }
   fclose(fp);
 


@@ -569,7 +640,7 @@ else if (errno == ENOENT)
   }
 else
   return tls_error(string_open_failed(errno, "\"%s\" for reading", filename),
   }
 else
   return tls_error(string_open_failed(errno, "\"%s\" for reading", filename),

-      NULL, NULL);
+      NULL, NULL, errstr);

 
 /* If ret < 0, either the cache file does not exist, or the data it contains
 is not useful. One particular case of this is when upgrading from an older
 
 /* If ret < 0, either the cache file does not exist, or the data it contains
 is not useful. One particular case of this is when upgrading from an older


@@ -584,12 +655,11 @@ if (rc < 0)
 
   if ((PATH_MAX - Ustrlen(filename)) < 10)
     return tls_error(US"Filename too long to generate replacement",
 
   if ((PATH_MAX - Ustrlen(filename)) < 10)
     return tls_error(US"Filename too long to generate replacement",

-        CS filename, NULL);
+        CS filename, NULL, errstr);

 
   temp_fn = string_copy(US "%s.XXXXXXX");
 
   temp_fn = string_copy(US "%s.XXXXXXX");

-  fd = mkstemp(CS temp_fn); /* modifies temp_fn */
-  if (fd < 0)
-    return tls_error(US"Unable to open temp file", strerror(errno), NULL);
+  if ((fd = mkstemp(CS temp_fn)) < 0)  /* modifies temp_fn */
+    return tls_error(US"Unable to open temp file", strerror(errno), NULL, errstr);

   (void)fchown(fd, exim_uid, exim_gid);   /* Probably not necessary */
 
   /* GnuTLS overshoots!
   (void)fchown(fd, exim_uid, exim_gid);   /* Probably not necessary */
 
   /* GnuTLS overshoots!


@@ -625,9 +695,9 @@ if (rc < 0)
   if (rc != GNUTLS_E_SHORT_MEMORY_BUFFER)
     exim_gnutls_err_check(US"gnutls_dh_params_export_pkcs3(NULL) sizing");
   m.size = sz;
   if (rc != GNUTLS_E_SHORT_MEMORY_BUFFER)
     exim_gnutls_err_check(US"gnutls_dh_params_export_pkcs3(NULL) sizing");
   m.size = sz;

-  m.data = malloc(m.size);
-  if (m.data == NULL)
-    return tls_error(US"memory allocation failed", strerror(errno), NULL);
+  if (!(m.data = malloc(m.size)))
+    return tls_error(US"memory allocation failed", strerror(errno), NULL, errstr);
+

   /* this will return a size 1 less than the allocation size above */
   rc = gnutls_dh_params_export_pkcs3(dh_server_params, GNUTLS_X509_FMT_PEM,
       m.data, &sz);
   /* this will return a size 1 less than the allocation size above */
   rc = gnutls_dh_params_export_pkcs3(dh_server_params, GNUTLS_X509_FMT_PEM,
       m.data, &sz);


@@ -638,27 +708,23 @@ if (rc < 0)
     }
   m.size = sz; /* shrink by 1, probably */
 
     }
   m.size = sz; /* shrink by 1, probably */
 

-  sz = write_to_fd_buf(fd, m.data, (size_t) m.size);
-  if (sz != m.size)
+  if ((sz = write_to_fd_buf(fd, m.data, (size_t) m.size)) != m.size)

     {
     free(m.data);
     return tls_error(US"TLS cache write D-H params failed",
     {
     free(m.data);
     return tls_error(US"TLS cache write D-H params failed",

-        strerror(errno), NULL);
+        strerror(errno), NULL, errstr);

     }
   free(m.data);
     }
   free(m.data);

-  sz = write_to_fd_buf(fd, US"\n", 1);
-  if (sz != 1)
+  if ((sz = write_to_fd_buf(fd, US"\n", 1)) != 1)

     return tls_error(US"TLS cache write D-H params final newline failed",
     return tls_error(US"TLS cache write D-H params final newline failed",

-        strerror(errno), NULL);
+        strerror(errno), NULL, errstr);

 
 

-  rc = close(fd);
-  if (rc)
-    return tls_error(US"TLS cache write close() failed",
-        strerror(errno), NULL);
+  if ((rc = close(fd)))
+    return tls_error(US"TLS cache write close() failed", strerror(errno), NULL, errstr);

 
   if (Urename(temp_fn, filename) < 0)
     return tls_error(string_sprintf("failed to rename \"%s\" as \"%s\"",
 
   if (Urename(temp_fn, filename) < 0)
     return tls_error(string_sprintf("failed to rename \"%s\" as \"%s\"",

-          temp_fn, filename), strerror(errno), NULL);
+          temp_fn, filename), strerror(errno), NULL, errstr);

 
   DEBUG(D_tls) debug_printf("wrote D-H parameters to file \"%s\"\n", filename);
   }
 
   DEBUG(D_tls) debug_printf("wrote D-H parameters to file \"%s\"\n", filename);
   }


@@ -670,6 +736,74 @@ return OK;
 
 
 
 
 
 

+/* Create and install a selfsigned certificate, for use in server mode */
+
+static int
+tls_install_selfsign(exim_gnutls_state_st * state, uschar ** errstr)
+{
+gnutls_x509_crt_t cert = NULL;
+time_t now;
+gnutls_x509_privkey_t pkey = NULL;
+const uschar * where;
+int rc;
+
+where = US"initialising pkey";
+if ((rc = gnutls_x509_privkey_init(&pkey))) goto err;
+
+where = US"initialising cert";
+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),
+#else
+           1024,
+#endif
+           0)))
+  goto err;
+
+where = US"configuring cert";
+now = 0;
+if (  (rc = gnutls_x509_crt_set_version(cert, 3))
+   || (rc = gnutls_x509_crt_set_serial(cert, &now, sizeof(now)))
+   || (rc = gnutls_x509_crt_set_activation_time(cert, now = time(NULL)))
+   || (rc = gnutls_x509_crt_set_expiration_time(cert, now + 60 * 60)) /* 1 hr */
+   || (rc = gnutls_x509_crt_set_key(cert, pkey))
+
+   || (rc = gnutls_x509_crt_set_dn_by_oid(cert,
+             GNUTLS_OID_X520_COUNTRY_NAME, 0, "UK", 2))
+   || (rc = gnutls_x509_crt_set_dn_by_oid(cert,
+             GNUTLS_OID_X520_ORGANIZATION_NAME, 0, "Exim Developers", 15))
+   || (rc = gnutls_x509_crt_set_dn_by_oid(cert,
+             GNUTLS_OID_X520_COMMON_NAME, 0,
+             smtp_active_hostname, Ustrlen(smtp_active_hostname)))
+   )
+  goto err;
+
+where = US"signing cert";
+if ((rc = gnutls_x509_crt_sign(cert, cert, pkey))) goto err;
+
+where = US"installing selfsign cert";
+                                       /* Since: 2.4.0 */
+if ((rc = gnutls_certificate_set_x509_key(state->x509_cred, &cert, 1, pkey)))
+  goto err;
+
+rc = OK;
+
+out:
+  if (cert) gnutls_x509_crt_deinit(cert);
+  if (pkey) gnutls_x509_privkey_deinit(pkey);
+  return rc;
+
+err:
+  rc = tls_error(where, gnutls_strerror(rc), NULL, errstr);
+  goto out;
+}
+
+
+
+

 /*************************************************
 *       Variables re-expanded post-SNI           *
 *************************************************/
 /*************************************************
 *       Variables re-expanded post-SNI           *
 *************************************************/


@@ -684,12 +818,13 @@ which we are responsible for setting on the first pass through.
 
 Arguments:
   state           exim_gnutls_state_st *
 
 Arguments:
   state           exim_gnutls_state_st *

+  errstr         error string pointer

 
 Returns:          OK/DEFER/FAIL
 */
 
 static int
 
 Returns:          OK/DEFER/FAIL
 */
 
 static int

-tls_expand_session_files(exim_gnutls_state_st *state)
+tls_expand_session_files(exim_gnutls_state_st *state, uschar ** errstr)

 {
 struct stat statbuf;
 int rc;
 {
 struct stat statbuf;
 int rc;


@@ -702,7 +837,6 @@ int cert_count;
 
 /* We check for tls_sni *before* expansion. */
 if (!host)     /* server */
 
 /* We check for tls_sni *before* expansion. */
 if (!host)     /* server */

-  {

   if (!state->received_sni)
     {
     if (state->tls_certificate &&
   if (!state->received_sni)
     {
     if (state->tls_certificate &&


@@ -723,7 +857,6 @@ if (!host)  /* server */
     saved_tls_verify_certificates = state->exp_tls_verify_certificates;
     saved_tls_crl = state->exp_tls_crl;
     }
     saved_tls_verify_certificates = state->exp_tls_verify_certificates;
     saved_tls_crl = state->exp_tls_crl;
     }

-  }

 
 rc = gnutls_certificate_allocate_credentials(&state->x509_cred);
 exim_gnutls_err_check(US"gnutls_certificate_allocate_credentials");
 
 rc = gnutls_certificate_allocate_credentials(&state->x509_cred);
 exim_gnutls_err_check(US"gnutls_certificate_allocate_credentials");


@@ -735,21 +868,20 @@ false if expansion failed, unless expansion was forced to fail. */
 /* check if we at least have a certificate, before doing expensive
 D-H generation. */
 
 /* check if we at least have a certificate, before doing expensive
 D-H generation. */
 

-if (!expand_check_tlsvar(tls_certificate))
+if (!expand_check_tlsvar(tls_certificate, errstr))

   return DEFER;
 
 /* certificate is mandatory in server, optional in client */
 
   return DEFER;
 
 /* certificate is mandatory in server, optional in client */
 

-if ((state->exp_tls_certificate == NULL) ||
-    (*state->exp_tls_certificate == '\0'))
-  {
+if (  !state->exp_tls_certificate
+   || !*state->exp_tls_certificate
+   )

   if (!host)
   if (!host)

-    return tls_error(US"no TLS server certificate is specified", NULL, NULL);
+    return tls_install_selfsign(state, errstr);

   else
     DEBUG(D_tls) debug_printf("TLS: no client certificate specified; okay\n");
   else
     DEBUG(D_tls) debug_printf("TLS: no client certificate specified; okay\n");

-  }

 
 

-if (state->tls_privatekey && !expand_check_tlsvar(tls_privatekey))
+if (state->tls_privatekey && !expand_check_tlsvar(tls_privatekey, errstr))

   return DEFER;
 
 /* tls_privatekey is optional, defaulting to same file as certificate */
   return DEFER;
 
 /* tls_privatekey is optional, defaulting to same file as certificate */


@@ -767,9 +899,9 @@ if (state->exp_tls_certificate && *state->exp_tls_certificate)
       state->exp_tls_certificate, state->exp_tls_privatekey);
 
   if (state->received_sni)
       state->exp_tls_certificate, state->exp_tls_privatekey);
 
   if (state->received_sni)

-    {
-    if ((Ustrcmp(state->exp_tls_certificate, saved_tls_certificate) == 0) &&
-        (Ustrcmp(state->exp_tls_privatekey, saved_tls_privatekey) == 0))
+    if (  Ustrcmp(state->exp_tls_certificate, saved_tls_certificate) == 0
+       && Ustrcmp(state->exp_tls_privatekey,  saved_tls_privatekey)  == 0
+       )

       {
       DEBUG(D_tls) debug_printf("TLS SNI: cert and key unchanged\n");
       }
       {
       DEBUG(D_tls) debug_printf("TLS SNI: cert and key unchanged\n");
       }


@@ -777,7 +909,6 @@ if (state->exp_tls_certificate && *state->exp_tls_certificate)
       {
       DEBUG(D_tls) debug_printf("TLS SNI: have a changed cert/key pair.\n");
       }
       {
       DEBUG(D_tls) debug_printf("TLS SNI: have a changed cert/key pair.\n");
       }

-    }

 
   rc = gnutls_certificate_set_x509_key_file(state->x509_cred,
       CS state->exp_tls_certificate, CS state->exp_tls_privatekey,
 
   rc = gnutls_certificate_set_x509_key_file(state->x509_cred,
       CS state->exp_tls_certificate, CS state->exp_tls_privatekey,


@@ -791,23 +922,30 @@ if (state->exp_tls_certificate && *state->exp_tls_certificate)
 
 /* Set the OCSP stapling server info */
 
 
 /* Set the OCSP stapling server info */
 

-#ifdef EXPERIMENTAL_OCSP
+#ifndef DISABLE_OCSP

 if (  !host    /* server */
    && tls_ocsp_file
    )
   {
 if (  !host    /* server */
    && tls_ocsp_file
    )
   {

-  if (!expand_check(tls_ocsp_file, US"tls_ocsp_file",
-       &state->exp_tls_ocsp_file))
-    return DEFER;
+  if (gnutls_buggy_ocsp)
+    {
+    DEBUG(D_tls) debug_printf("GnuTLS library is buggy for OCSP; avoiding\n");
+    }
+  else
+    {
+    if (!expand_check(tls_ocsp_file, US"tls_ocsp_file",
+         &state->exp_tls_ocsp_file, errstr))
+      return DEFER;

 
 

-  /* Use the full callback method for stapling just to get observability.
-  More efficient would be to read the file once only, if it never changed
-  (due to SNI). Would need restart on file update, or watch datestamp.  */
+    /* Use the full callback method for stapling just to get observability.
+    More efficient would be to read the file once only, if it never changed
+    (due to SNI). Would need restart on file update, or watch datestamp.  */

 
 

-  gnutls_certificate_set_ocsp_status_request_function(state->x509_cred,
-    server_ocsp_stapling_cb, state->exp_tls_ocsp_file);
+    gnutls_certificate_set_ocsp_status_request_function(state->x509_cred,
+      server_ocsp_stapling_cb, state->exp_tls_ocsp_file);

 
 

-  DEBUG(D_tls) debug_printf("Set OCSP response file %s\n", &state->exp_tls_ocsp_file);
+    DEBUG(D_tls) debug_printf("OCSP response file = %s\n", state->exp_tls_ocsp_file);
+    }

   }
 #endif
 
   }
 #endif
 


@@ -820,10 +958,14 @@ behaviour. */
 
 if (state->tls_verify_certificates && *state->tls_verify_certificates)
   {
 
 if (state->tls_verify_certificates && *state->tls_verify_certificates)
   {

-  if (!expand_check_tlsvar(tls_verify_certificates))
+  if (!expand_check_tlsvar(tls_verify_certificates, errstr))

     return DEFER;
     return DEFER;

+#ifndef SUPPORT_SYSDEFAULT_CABUNDLE
+  if (Ustrcmp(state->exp_tls_verify_certificates, "system") == 0)
+    state->exp_tls_verify_certificates = NULL;
+#endif

   if (state->tls_crl && *state->tls_crl)
   if (state->tls_crl && *state->tls_crl)

-    if (!expand_check_tlsvar(tls_crl))
+    if (!expand_check_tlsvar(tls_crl, errstr))

       return DEFER;
 
   if (!(state->exp_tls_verify_certificates &&
       return DEFER;
 
   if (!(state->exp_tls_verify_certificates &&


@@ -842,46 +984,65 @@ else
   return OK;
   }
 
   return OK;
   }
 

-if (Ustat(state->exp_tls_verify_certificates, &statbuf) < 0)
+#ifdef SUPPORT_SYSDEFAULT_CABUNDLE
+if (Ustrcmp(state->exp_tls_verify_certificates, "system") == 0)
+  cert_count = gnutls_certificate_set_x509_system_trust(state->x509_cred);
+else
+#endif

   {
   {

-  log_write(0, LOG_MAIN|LOG_PANIC, "could not stat %s "
-      "(tls_verify_certificates): %s", state->exp_tls_verify_certificates,
-      strerror(errno));
-  return DEFER;
-  }
+  if (Ustat(state->exp_tls_verify_certificates, &statbuf) < 0)
+    {
+    log_write(0, LOG_MAIN|LOG_PANIC, "could not stat %s "
+       "(tls_verify_certificates): %s", state->exp_tls_verify_certificates,
+       strerror(errno));
+    return DEFER;
+    }

 
 

-/* The test suite passes in /dev/null; we could check for that path explicitly,
-but who knows if someone has some weird FIFO which always dumps some certs, or
-other weirdness.  The thing we really want to check is that it's not a
-directory, since while OpenSSL supports that, GnuTLS does not.
-So s/!S_ISREG/S_ISDIR/ and change some messsaging ... */
-if (S_ISDIR(statbuf.st_mode))
-  {
-  DEBUG(D_tls)
-    debug_printf("verify certificates path is a dir: \"%s\"\n",
-        state->exp_tls_verify_certificates);
-  log_write(0, LOG_MAIN|LOG_PANIC,
-      "tls_verify_certificates \"%s\" is a directory",
-      state->exp_tls_verify_certificates);
-  return DEFER;
-  }
+#ifndef SUPPORT_CA_DIR
+  /* The test suite passes in /dev/null; we could check for that path explicitly,
+  but who knows if someone has some weird FIFO which always dumps some certs, or
+  other weirdness.  The thing we really want to check is that it's not a
+  directory, since while OpenSSL supports that, GnuTLS does not.
+  So s/!S_ISREG/S_ISDIR/ and change some messaging ... */
+  if (S_ISDIR(statbuf.st_mode))
+    {
+    DEBUG(D_tls)
+      debug_printf("verify certificates path is a dir: \"%s\"\n",
+         state->exp_tls_verify_certificates);
+    log_write(0, LOG_MAIN|LOG_PANIC,
+       "tls_verify_certificates \"%s\" is a directory",
+       state->exp_tls_verify_certificates);
+    return DEFER;
+    }
+#endif

 
 

-DEBUG(D_tls) debug_printf("verify certificates = %s size=" OFF_T_FMT "\n",
-        state->exp_tls_verify_certificates, statbuf.st_size);
+  DEBUG(D_tls) debug_printf("verify certificates = %s size=" OFF_T_FMT "\n",
+         state->exp_tls_verify_certificates, statbuf.st_size);

 
 

-if (statbuf.st_size == 0)
-  {
-  DEBUG(D_tls)
-    debug_printf("cert file empty, no certs, no verification, ignoring any CRL\n");
-  return OK;
+  if (statbuf.st_size == 0)
+    {
+    DEBUG(D_tls)
+      debug_printf("cert file empty, no certs, no verification, ignoring any CRL\n");
+    return OK;
+    }
+
+  cert_count =
+
+#ifdef SUPPORT_CA_DIR
+    (statbuf.st_mode & S_IFMT) == S_IFDIR
+    ?
+    gnutls_certificate_set_x509_trust_dir(state->x509_cred,
+      CS state->exp_tls_verify_certificates, GNUTLS_X509_FMT_PEM)
+    :
+#endif
+    gnutls_certificate_set_x509_trust_file(state->x509_cred,
+      CS state->exp_tls_verify_certificates, GNUTLS_X509_FMT_PEM);

   }
 
   }
 

-cert_count = gnutls_certificate_set_x509_trust_file(state->x509_cred,
-    CS state->exp_tls_verify_certificates, GNUTLS_X509_FMT_PEM);

 if (cert_count < 0)
   {
   rc = cert_count;
 if (cert_count < 0)
   {
   rc = cert_count;

-  exim_gnutls_err_check(US"gnutls_certificate_set_x509_trust_file");
+  exim_gnutls_err_check(US"setting certificate trust");

   }
 DEBUG(D_tls) debug_printf("Added %d certificate authorities.\n", cert_count);
 
   }
 DEBUG(D_tls) debug_printf("Added %d certificate authorities.\n", cert_count);
 


@@ -917,12 +1078,13 @@ out to this.
 
 Arguments:
   state           exim_gnutls_state_st *
 
 Arguments:
   state           exim_gnutls_state_st *

+  errstr         error string pointer

 
 Returns:          OK/DEFER/FAIL
 */
 
 static int
 
 Returns:          OK/DEFER/FAIL
 */
 
 static int

-tls_set_remaining_x509(exim_gnutls_state_st *state)
+tls_set_remaining_x509(exim_gnutls_state_st *state, uschar ** errstr)

 {
 int rc;
 const host_item *host = state->host;  /* macro should be reconsidered? */
 {
 int rc;
 const host_item *host = state->host;  /* macro should be reconsidered? */


@@ -935,7 +1097,7 @@ if (!state->host)
   {
   if (!dh_server_params)
     {
   {
   if (!dh_server_params)
     {

-    rc = init_server_dh();
+    rc = init_server_dh(errstr);

     if (rc != OK) return rc;
     }
   gnutls_certificate_set_dh_params(state->x509_cred, dh_server_params);
     if (rc != OK) return rc;
     }
   gnutls_certificate_set_dh_params(state->x509_cred, dh_server_params);


@@ -953,6 +1115,38 @@ return OK;
 *            Initialize for GnuTLS               *
 *************************************************/
 
 *            Initialize for GnuTLS               *
 *************************************************/
 

+
+#ifndef DISABLE_OCSP
+
+static BOOL
+tls_is_buggy_ocsp(void)
+{
+const uschar * s;
+uschar maj, mid, mic;
+
+s = CUS gnutls_check_version(NULL);
+maj = atoi(CCS s);
+if (maj == 3)
+  {
+  while (*s && *s != '.') s++;
+  mid = atoi(CCS ++s);
+  if (mid <= 2)
+    return TRUE;
+  else if (mid >= 5)
+    return FALSE;
+  else
+    {
+    while (*s && *s != '.') s++;
+    mic = atoi(CCS ++s);
+    return mic <= (mid == 3 ? 16 : 3);
+    }
+  }
+return FALSE;
+}
+
+#endif
+
+

 /* Called from both server and client code. In the case of a server, errors
 before actual TLS negotiation return DEFER.
 
 /* Called from both server and client code. In the case of a server, errors
 before actual TLS negotiation return DEFER.
 


@@ -965,6 +1159,7 @@ Arguments:
   crl             CRL file
   require_ciphers tls_require_ciphers setting
   caller_state    returned state-info structure
   crl             CRL file
   require_ciphers tls_require_ciphers setting
   caller_state    returned state-info structure

+  errstr         error string pointer

 
 Returns:          OK/DEFER/FAIL
 */
 
 Returns:          OK/DEFER/FAIL
 */


@@ -978,7 +1173,8 @@ tls_init(
     const uschar *cas,
     const uschar *crl,
     const uschar *require_ciphers,
     const uschar *cas,
     const uschar *crl,
     const uschar *require_ciphers,

-    exim_gnutls_state_st **caller_state)
+    exim_gnutls_state_st **caller_state,
+    uschar ** errstr)

 {
 exim_gnutls_state_st *state;
 int rc;
 {
 exim_gnutls_state_st *state;
 int rc;


@@ -1016,6 +1212,11 @@ if (!exim_gnutls_base_init_done)
     }
 #endif
 
     }
 #endif
 

+#ifndef DISABLE_OCSP
+  if (tls_ocsp_file && (gnutls_buggy_ocsp = tls_is_buggy_ocsp()))
+    log_write(0, LOG_MAIN, "OCSP unusable with this GnuTLS library version");
+#endif
+

   exim_gnutls_base_init_done = TRUE;
   }
 
   exim_gnutls_base_init_done = TRUE;
   }
 


@@ -1051,27 +1252,25 @@ that's tls_certificate, tls_privatekey, tls_verify_certificates, tls_crl */
 
 DEBUG(D_tls)
   debug_printf("Expanding various TLS configuration options for session credentials.\n");
 
 DEBUG(D_tls)
   debug_printf("Expanding various TLS configuration options for session credentials.\n");

-rc = tls_expand_session_files(state);
-if (rc != OK) return rc;
+if ((rc = tls_expand_session_files(state, errstr)) != OK) return rc;

 
 /* These are all other parts of the x509_cred handling, since SNI in GnuTLS
 requires a new structure afterwards. */
 
 
 /* These are all other parts of the x509_cred handling, since SNI in GnuTLS
 requires a new structure afterwards. */
 

-rc = tls_set_remaining_x509(state);
-if (rc != OK) return rc;
+if ((rc = tls_set_remaining_x509(state, errstr)) != OK) return rc;

 
 /* set SNI in client, only */
 if (host)
   {
 
 /* set SNI in client, only */
 if (host)
   {

-  if (!expand_check(state->tlsp->sni, US"tls_out_sni", &state->exp_tls_sni))
+  if (!expand_check(sni, US"tls_out_sni", &state->tlsp->sni, errstr))

     return DEFER;
     return DEFER;

-  if (state->exp_tls_sni && *state->exp_tls_sni)
+  if (state->tlsp->sni && *state->tlsp->sni)

     {
     DEBUG(D_tls)
     {
     DEBUG(D_tls)

-      debug_printf("Setting TLS client SNI to \"%s\"\n", state->exp_tls_sni);
-    sz = Ustrlen(state->exp_tls_sni);
+      debug_printf("Setting TLS client SNI to \"%s\"\n", state->tlsp->sni);
+    sz = Ustrlen(state->tlsp->sni);

     rc = gnutls_server_name_set(state->session,
     rc = gnutls_server_name_set(state->session,

-        GNUTLS_NAME_DNS, state->exp_tls_sni, sz);
+        GNUTLS_NAME_DNS, state->tlsp->sni, sz);

     exim_gnutls_err_check(US"gnutls_server_name_set");
     }
   }
     exim_gnutls_err_check(US"gnutls_server_name_set");
     }
   }


@@ -1089,7 +1288,7 @@ want_default_priorities = TRUE;
 
 if (state->tls_require_ciphers && *state->tls_require_ciphers)
   {
 
 if (state->tls_require_ciphers && *state->tls_require_ciphers)
   {

-  if (!expand_check_tlsvar(tls_require_ciphers))
+  if (!expand_check_tlsvar(tls_require_ciphers, errstr))

     return DEFER;
   if (state->exp_tls_require_ciphers && *state->exp_tls_require_ciphers)
     {
     return DEFER;
   if (state->exp_tls_require_ciphers && *state->exp_tls_require_ciphers)
     {


@@ -1163,15 +1362,16 @@ don't apply.
 
 Arguments:
   state           exim_gnutls_state_st *
 
 Arguments:
   state           exim_gnutls_state_st *

+  errstr         pointer to error string

 
 Returns:          OK/DEFER/FAIL
 */
 
 static int
 
 Returns:          OK/DEFER/FAIL
 */
 
 static int

-peer_status(exim_gnutls_state_st *state)
+peer_status(exim_gnutls_state_st *state, uschar ** errstr)

 {
 uschar cipherbuf[256];
 {
 uschar cipherbuf[256];

-const gnutls_datum *cert_list;
+const gnutls_datum_t *cert_list;

 int old_pool, rc;
 unsigned int cert_list_size = 0;
 gnutls_protocol_t protocol;
 int old_pool, rc;
 unsigned int cert_list_size = 0;
 gnutls_protocol_t protocol;


@@ -1220,9 +1420,9 @@ if (cert_list == NULL || cert_list_size == 0)
   {
   DEBUG(D_tls) debug_printf("TLS: no certificate from peer (%p & %d)\n",
       cert_list, cert_list_size);
   {
   DEBUG(D_tls) debug_printf("TLS: no certificate from peer (%p & %d)\n",
       cert_list, cert_list_size);

-  if (state->verify_requirement == VERIFY_REQUIRED)
+  if (state->verify_requirement >= VERIFY_REQUIRED)

     return tls_error(US"certificate verification failed",
     return tls_error(US"certificate verification failed",

-        "no certificate received from peer", state->host);
+        "no certificate received from peer", state->host, errstr);

   return OK;
   }
 
   return OK;
   }
 


@@ -1232,17 +1432,23 @@ if (ct != GNUTLS_CRT_X509)
   const char *ctn = gnutls_certificate_type_get_name(ct);
   DEBUG(D_tls)
     debug_printf("TLS: peer cert not X.509 but instead \"%s\"\n", ctn);
   const char *ctn = gnutls_certificate_type_get_name(ct);
   DEBUG(D_tls)
     debug_printf("TLS: peer cert not X.509 but instead \"%s\"\n", ctn);

-  if (state->verify_requirement == VERIFY_REQUIRED)
+  if (state->verify_requirement >= VERIFY_REQUIRED)

     return tls_error(US"certificate verification not possible, unhandled type",
     return tls_error(US"certificate verification not possible, unhandled type",

-        ctn, state->host);
+        ctn, state->host, errstr);

   return OK;
   }
 
   return OK;
   }
 

-#define exim_gnutls_peer_err(Label) do { \
-  if (rc != GNUTLS_E_SUCCESS) { \
-    DEBUG(D_tls) debug_printf("TLS: peer cert problem: %s: %s\n", (Label), gnutls_strerror(rc)); \
-    if (state->verify_requirement == VERIFY_REQUIRED) { return tls_error((Label), gnutls_strerror(rc), state->host); } \
-    return OK; } } while (0)
+#define exim_gnutls_peer_err(Label) \
+  do { \
+    if (rc != GNUTLS_E_SUCCESS) \
+      { \
+      DEBUG(D_tls) debug_printf("TLS: peer cert problem: %s: %s\n", \
+       (Label), gnutls_strerror(rc)); \
+      if (state->verify_requirement >= VERIFY_REQUIRED) \
+       return tls_error((Label), gnutls_strerror(rc), state->host, errstr); \
+      return OK; \
+      } \
+    } while (0)

 
 rc = import_cert(&cert_list[0], &crt);
 exim_gnutls_peer_err(US"cert 0");
 
 rc = import_cert(&cert_list[0], &crt);
 exim_gnutls_peer_err(US"cert 0");


@@ -1280,7 +1486,7 @@ the peer information, but that's too new for some OSes.
 
 Arguments:
   state           exim_gnutls_state_st *
 
 Arguments:
   state           exim_gnutls_state_st *

-  error           where to put an error message
+  errstr          where to put an error message

 
 Returns:
   FALSE     if the session should be rejected
 
 Returns:
   FALSE     if the session should be rejected


@@ -1288,17 +1494,17 @@ Returns:
 */
 
 static BOOL
 */
 
 static BOOL

-verify_certificate(exim_gnutls_state_st *state, const char **error)
+verify_certificate(exim_gnutls_state_st *state, uschar ** errstr)

 {
 int rc;
 unsigned int verify;
 
 {
 int rc;
 unsigned int verify;
 

-*error = NULL;
+*errstr = NULL;

 
 

-if ((rc = peer_status(state)) != OK)
+if ((rc = peer_status(state, errstr)) != OK)

   {
   verify = GNUTLS_CERT_INVALID;
   {
   verify = GNUTLS_CERT_INVALID;

-  *error = "certificate not supplied";
+  *errstr = US"certificate not supplied";

   }
 else
   rc = gnutls_certificate_verify_peers2(state->session, &verify);
   }
 else
   rc = gnutls_certificate_verify_peers2(state->session, &verify);


@@ -1306,29 +1512,54 @@ else
 /* Handle the result of verification. INVALID seems to be set as well
 as REVOKED, but leave the test for both. */
 
 /* Handle the result of verification. INVALID seems to be set as well
 as REVOKED, but leave the test for both. */
 

-if (rc < 0 || verify & (GNUTLS_CERT_INVALID|GNUTLS_CERT_REVOKED))
+if (rc < 0 ||
+    verify & (GNUTLS_CERT_INVALID|GNUTLS_CERT_REVOKED)
+   )

   {
   state->peer_cert_verified = FALSE;
   {
   state->peer_cert_verified = FALSE;

-  if (!*error)
-    *error = verify & GNUTLS_CERT_REVOKED
-      ? "certificate revoked" : "certificate invalid";
+  if (!*errstr)
+    *errstr = verify & GNUTLS_CERT_REVOKED
+      ? US"certificate revoked" : US"certificate invalid";

 
   DEBUG(D_tls)
 
   DEBUG(D_tls)

-    debug_printf("TLS certificate verification failed (%s): peerdn=%s\n",
-        *error, state->peerdn ? state->peerdn : US"<unset>");
+    debug_printf("TLS certificate verification failed (%s): peerdn=\"%s\"\n",
+        *errstr, state->peerdn ? state->peerdn : US"<unset>");

 
 

-  if (state->verify_requirement == VERIFY_REQUIRED)
+  if (state->verify_requirement >= VERIFY_REQUIRED)

     {
     {

-    gnutls_alert_send(state->session, GNUTLS_AL_FATAL, GNUTLS_A_BAD_CERTIFICATE);
+    gnutls_alert_send(state->session,
+      GNUTLS_AL_FATAL, GNUTLS_A_BAD_CERTIFICATE);

     return FALSE;
     }
   DEBUG(D_tls)
     debug_printf("TLS verify failure overridden (host in tls_try_verify_hosts)\n");
   }
     return FALSE;
     }
   DEBUG(D_tls)
     debug_printf("TLS verify failure overridden (host in tls_try_verify_hosts)\n");
   }

+

 else
   {
 else
   {

+  if (state->exp_tls_verify_cert_hostnames)
+    {
+    int sep = 0;
+    const uschar * list = state->exp_tls_verify_cert_hostnames;
+    uschar * name;
+    while ((name = string_nextinlist(&list, &sep, NULL, 0)))
+      if (gnutls_x509_crt_check_hostname(state->tlsp->peercert, CS name))
+       break;
+    if (!name)
+      {
+      DEBUG(D_tls)
+       debug_printf("TLS certificate verification failed: cert name mismatch\n");
+      if (state->verify_requirement >= VERIFY_REQUIRED)
+       {
+       gnutls_alert_send(state->session,
+         GNUTLS_AL_FATAL, GNUTLS_A_BAD_CERTIFICATE);
+       return FALSE;
+       }
+      return TRUE;
+      }
+    }

   state->peer_cert_verified = TRUE;
   state->peer_cert_verified = TRUE;

-  DEBUG(D_tls) debug_printf("TLS certificate verified: peerdn=%s\n",
+  DEBUG(D_tls) debug_printf("TLS certificate verified: peerdn=\"%s\"\n",

       state->peerdn ? state->peerdn : US"<unset>");
   }
 
       state->peerdn ? state->peerdn : US"<unset>");
   }
 


@@ -1387,6 +1618,7 @@ size_t data_len = MAX_HOST_LEN;
 exim_gnutls_state_st *state = &state_server;
 unsigned int sni_type;
 int rc, old_pool;
 exim_gnutls_state_st *state = &state_server;
 unsigned int sni_type;
 int rc, old_pool;

+uschar * dummy_errstr;

 
 rc = gnutls_server_name_get(session, sni_name, &data_len, &sni_type, 0);
 if (rc != GNUTLS_E_SUCCESS)
 
 rc = gnutls_server_name_get(session, sni_name, &data_len, &sni_type, 0);
 if (rc != GNUTLS_E_SUCCESS)


@@ -1397,7 +1629,7 @@ if (rc != GNUTLS_E_SUCCESS)
     else
       debug_printf("TLS failure: gnutls_server_name_get(): %s [%d]\n",
         gnutls_strerror(rc), rc);
     else
       debug_printf("TLS failure: gnutls_server_name_get(): %s [%d]\n",
         gnutls_strerror(rc), rc);

-  };
+    }

   return 0;
   }
 
   return 0;
   }
 


@@ -1422,15 +1654,14 @@ DEBUG(D_tls) debug_printf("Received TLS SNI \"%s\"%s\n", sni_name,
 if (!state->trigger_sni_changes)
   return 0;
 
 if (!state->trigger_sni_changes)
   return 0;
 

-rc = tls_expand_session_files(state);
-if (rc != OK)
+if ((rc = tls_expand_session_files(state, &dummy_errstr)) != OK)

   {
   /* If the setup of certs/etc failed before handshake, TLS would not have
   been offered.  The best we can do now is abort. */
   return GNUTLS_E_APPLICATION_ERROR_MIN;
   }
 
   {
   /* If the setup of certs/etc failed before handshake, TLS would not have
   been offered.  The best we can do now is abort. */
   return GNUTLS_E_APPLICATION_ERROR_MIN;
   }
 

-rc = tls_set_remaining_x509(state);
+rc = tls_set_remaining_x509(state, &dummy_errstr);

 if (rc != OK) return GNUTLS_E_APPLICATION_ERROR_MIN;
 
 return 0;
 if (rc != OK) return GNUTLS_E_APPLICATION_ERROR_MIN;
 
 return 0;


@@ -1438,7 +1669,7 @@ return 0;
 
 
 
 
 
 

-#ifdef EXPERIMENTAL_OCSP
+#ifndef DISABLE_OCSP

 
 static int
 server_ocsp_stapling_cb(gnutls_session_t session, void * ptr,
 
 static int
 server_ocsp_stapling_cb(gnutls_session_t session, void * ptr,


@@ -1449,7 +1680,7 @@ int ret;
 if ((ret = gnutls_load_file(ptr, ocsp_response)) < 0)
   {
   DEBUG(D_tls) debug_printf("Failed to load ocsp stapling file %s\n",
 if ((ret = gnutls_load_file(ptr, ocsp_response)) < 0)
   {
   DEBUG(D_tls) debug_printf("Failed to load ocsp stapling file %s\n",

-                             (char *)ptr);
+                             CS ptr);

   tls_in.ocsp = OCSP_NOT_RESP;
   return GNUTLS_E_NO_CERTIFICATE_STATUS;
   }
   tls_in.ocsp = OCSP_NOT_RESP;
   return GNUTLS_E_NO_CERTIFICATE_STATUS;
   }


@@ -1461,6 +1692,54 @@ return 0;
 #endif
 
 
 #endif
 
 

+#ifndef DISABLE_EVENT
+/*
+We use this callback to get observability and detail-level control
+for an exim TLS connection (either direction), raising a tls:cert event
+for each cert in the chain presented by the peer.  Any event
+can deny verification.
+
+Return 0 for the handshake to continue or non-zero to terminate.
+*/
+
+static int
+verify_cb(gnutls_session_t session)
+{
+const gnutls_datum_t * cert_list;
+unsigned int cert_list_size = 0;
+gnutls_x509_crt_t crt;
+int rc;
+uschar * yield;
+exim_gnutls_state_st * state = gnutls_session_get_ptr(session);
+
+cert_list = gnutls_certificate_get_peers(session, &cert_list_size);
+if (cert_list)
+  while (cert_list_size--)
+  {
+  rc = import_cert(&cert_list[cert_list_size], &crt);
+  if (rc != GNUTLS_E_SUCCESS)
+    {
+    DEBUG(D_tls) debug_printf("TLS: peer cert problem: depth %d: %s\n",
+      cert_list_size, gnutls_strerror(rc));
+    break;
+    }
+
+  state->tlsp->peercert = crt;
+  if ((yield = event_raise(state->event_action,
+             US"tls:cert", string_sprintf("%d", cert_list_size))))
+    {
+    log_write(0, LOG_MAIN,
+             "SSL verify denied by event-action: depth=%d: %s",
+             cert_list_size, yield);
+    return 1;                     /* reject */
+    }
+  state->tlsp->peercert = NULL;
+  }
+
+return 0;
+}
+
+#endif

 
 
 
 
 
 


@@ -1480,25 +1759,25 @@ a TLS session.
 
 Arguments:
   require_ciphers  list of allowed ciphers or NULL
 
 Arguments:
   require_ciphers  list of allowed ciphers or NULL

+  errstr          pointer to error string

 
 Returns:           OK on success
                    DEFER for errors before the start of the negotiation
 
 Returns:           OK on success
                    DEFER for errors before the start of the negotiation

-                   FAIL for errors during the negotation; the server can't
+                   FAIL for errors during the negotiation; the server can't

                      continue running.
 */
 
 int
                      continue running.
 */
 
 int

-tls_server_start(const uschar *require_ciphers)
+tls_server_start(const uschar * require_ciphers, uschar ** errstr)

 {
 int rc;
 {
 int rc;

-const char *error;
-exim_gnutls_state_st *state = NULL;
+exim_gnutls_state_st * state = NULL;

 
 /* Check for previous activation */
 if (tls_in.active >= 0)
   {
 
 /* Check for previous activation */
 if (tls_in.active >= 0)
   {

-  tls_error(US"STARTTLS received after TLS started", "", NULL);
-  smtp_printf("554 Already in TLS\r\n");
+  tls_error(US"STARTTLS received after TLS started", "", NULL, errstr);
+  smtp_printf("554 Already in TLS\r\n", FALSE);

   return FAIL;
   }
 
   return FAIL;
   }
 


@@ -1507,33 +1786,44 @@ and sent an SMTP response. */
 
 DEBUG(D_tls) debug_printf("initialising GnuTLS as a server\n");
 
 
 DEBUG(D_tls) debug_printf("initialising GnuTLS as a server\n");
 

-rc = tls_init(NULL, tls_certificate, tls_privatekey,
+if ((rc = tls_init(NULL, tls_certificate, tls_privatekey,

     NULL, tls_verify_certificates, tls_crl,
     NULL, tls_verify_certificates, tls_crl,

-    require_ciphers, &state);
-if (rc != OK) return rc;
+    require_ciphers, &state, errstr)) != OK) return rc;

 
 /* If this is a host for which certificate verification is mandatory or
 optional, set up appropriately. */
 
 if (verify_check_host(&tls_verify_hosts) == OK)
   {
 
 /* If this is a host for which certificate verification is mandatory or
 optional, set up appropriately. */
 
 if (verify_check_host(&tls_verify_hosts) == OK)
   {

-  DEBUG(D_tls) debug_printf("TLS: a client certificate will be required.\n");
+  DEBUG(D_tls)
+    debug_printf("TLS: a client certificate will be required.\n");

   state->verify_requirement = VERIFY_REQUIRED;
   gnutls_certificate_server_set_request(state->session, GNUTLS_CERT_REQUIRE);
   }
 else if (verify_check_host(&tls_try_verify_hosts) == OK)
   {
   state->verify_requirement = VERIFY_REQUIRED;
   gnutls_certificate_server_set_request(state->session, GNUTLS_CERT_REQUIRE);
   }
 else if (verify_check_host(&tls_try_verify_hosts) == OK)
   {

-  DEBUG(D_tls) debug_printf("TLS: a client certificate will be requested but not required.\n");
+  DEBUG(D_tls)
+    debug_printf("TLS: a client certificate will be requested but not required.\n");

   state->verify_requirement = VERIFY_OPTIONAL;
   gnutls_certificate_server_set_request(state->session, GNUTLS_CERT_REQUEST);
   }
 else
   {
   state->verify_requirement = VERIFY_OPTIONAL;
   gnutls_certificate_server_set_request(state->session, GNUTLS_CERT_REQUEST);
   }
 else
   {

-  DEBUG(D_tls) debug_printf("TLS: a client certificate will not be requested.\n");
+  DEBUG(D_tls)
+    debug_printf("TLS: a client certificate will not be requested.\n");

   state->verify_requirement = VERIFY_NONE;
   gnutls_certificate_server_set_request(state->session, GNUTLS_CERT_IGNORE);
   }
 
   state->verify_requirement = VERIFY_NONE;
   gnutls_certificate_server_set_request(state->session, GNUTLS_CERT_IGNORE);
   }
 

+#ifndef DISABLE_EVENT
+if (event_action)
+  {
+  state->event_action = event_action;
+  gnutls_session_set_ptr(state->session, state);
+  gnutls_certificate_set_verify_function(state->x509_cred, verify_cb);
+  }
+#endif
+

 /* Register SNI handling; always, even if not in tls_certificate, so that the
 expansion variable $tls_sni is always available. */
 
 /* Register SNI handling; always, even if not in tls_certificate, so that the
 expansion variable $tls_sni is always available. */
 


@@ -1548,7 +1838,7 @@ mode, the fflush() happens when smtp_getc() is called. */
 
 if (!state->tlsp->on_connect)
   {
 
 if (!state->tlsp->on_connect)
   {

-  smtp_printf("220 TLS go ahead\r\n");
+  smtp_printf("220 TLS go ahead\r\n", FALSE);

   fflush(smtp_out);
   }
 
   fflush(smtp_out);
   }
 


@@ -1556,32 +1846,41 @@ if (!state->tlsp->on_connect)
 that the GnuTLS library doesn't. */
 
 gnutls_transport_set_ptr2(state->session,
 that the GnuTLS library doesn't. */
 
 gnutls_transport_set_ptr2(state->session,

-    (gnutls_transport_ptr)(long) fileno(smtp_in),
-    (gnutls_transport_ptr)(long) fileno(smtp_out));
+    (gnutls_transport_ptr_t)(long) fileno(smtp_in),
+    (gnutls_transport_ptr_t)(long) fileno(smtp_out));

 state->fd_in = fileno(smtp_in);
 state->fd_out = fileno(smtp_out);
 
 sigalrm_seen = FALSE;
 if (smtp_receive_timeout > 0) alarm(smtp_receive_timeout);
 do
 state->fd_in = fileno(smtp_in);
 state->fd_out = fileno(smtp_out);
 
 sigalrm_seen = FALSE;
 if (smtp_receive_timeout > 0) alarm(smtp_receive_timeout);
 do

-  {

   rc = gnutls_handshake(state->session);
   rc = gnutls_handshake(state->session);

-  } while ((rc == GNUTLS_E_AGAIN) ||
-      (rc == GNUTLS_E_INTERRUPTED && !sigalrm_seen));
+while (rc == GNUTLS_E_AGAIN ||  rc == GNUTLS_E_INTERRUPTED && !sigalrm_seen);

 alarm(0);
 
 if (rc != GNUTLS_E_SUCCESS)
   {
 alarm(0);
 
 if (rc != GNUTLS_E_SUCCESS)
   {

-  tls_error(US"gnutls_handshake",
-      sigalrm_seen ? "timed out" : gnutls_strerror(rc), NULL);

   /* It seems that, except in the case of a timeout, we have to close the
   connection right here; otherwise if the other end is running OpenSSL it hangs
   until the server times out. */
 
   /* It seems that, except in the case of a timeout, we have to close the
   connection right here; otherwise if the other end is running OpenSSL it hangs
   until the server times out. */
 

-  if (!sigalrm_seen)
+  if (sigalrm_seen)
+    {
+    tls_error(US"gnutls_handshake", "timed out", NULL, errstr);
+    gnutls_db_remove_session(state->session);
+    }
+  else

     {
     {

+    tls_error(US"gnutls_handshake", gnutls_strerror(rc), NULL, errstr);
+    (void) gnutls_alert_send_appropriate(state->session, rc);
+    gnutls_deinit(state->session);
+    gnutls_certificate_free_credentials(state->x509_cred);
+    millisleep(500);
+    shutdown(state->fd_out, SHUT_WR);
+    for (rc = 1024; fgetc(smtp_in) != EOF && rc > 0; ) rc--;   /* drain skt */

     (void)fclose(smtp_out);
     (void)fclose(smtp_in);
     (void)fclose(smtp_out);
     (void)fclose(smtp_in);

+    smtp_out = smtp_in = NULL;

     }
 
   return FAIL;
     }
 
   return FAIL;


@@ -1592,22 +1891,21 @@ DEBUG(D_tls) debug_printf("gnutls_handshake was successful\n");
 /* Verify after the fact */
 
 if (  state->verify_requirement != VERIFY_NONE
 /* Verify after the fact */
 
 if (  state->verify_requirement != VERIFY_NONE

-   && !verify_certificate(state, &error))
+   && !verify_certificate(state, errstr))

   {
   if (state->verify_requirement != VERIFY_OPTIONAL)
     {
   {
   if (state->verify_requirement != VERIFY_OPTIONAL)
     {

-    tls_error(US"certificate verification failed", error, NULL);
+    (void) tls_error(US"certificate verification failed", *errstr, NULL, errstr);

     return FAIL;
     }
   DEBUG(D_tls)
     debug_printf("TLS: continuing on only because verification was optional, after: %s\n",
     return FAIL;
     }
   DEBUG(D_tls)
     debug_printf("TLS: continuing on only because verification was optional, after: %s\n",

-       error);
+       *errstr);

   }
 
 /* Figure out peer DN, and if authenticated, etc. */
 
   }
 
 /* Figure out peer DN, and if authenticated, etc. */
 

-rc = peer_status(state);
-if (rc != OK) return rc;
+if ((rc = peer_status(state, NULL)) != OK) return rc;

 
 /* Sets various Exim expansion variables; always safe within server */
 
 
 /* Sets various Exim expansion variables; always safe within server */
 


@@ -1619,6 +1917,8 @@ and initialize appropriately. */
 state->xfer_buffer = store_malloc(ssl_xfer_buffer_size);
 
 receive_getc = tls_getc;
 state->xfer_buffer = store_malloc(ssl_xfer_buffer_size);
 
 receive_getc = tls_getc;

+receive_getbuf = tls_getbuf;
+receive_get_cache = tls_get_cache;

 receive_ungetc = tls_ungetc;
 receive_feof = tls_feof;
 receive_ferror = tls_ferror;
 receive_ungetc = tls_ungetc;
 receive_feof = tls_feof;
 receive_ferror = tls_ferror;


@@ -1630,6 +1930,25 @@ return OK;
 
 
 
 
 
 

+static void
+tls_client_setup_hostname_checks(host_item * host, exim_gnutls_state_st * state,
+  smtp_transport_options_block * ob)
+{
+if (verify_check_given_host(&ob->tls_verify_cert_hostnames, host) == OK)
+  {
+  state->exp_tls_verify_cert_hostnames =
+#ifdef SUPPORT_I18N
+    string_domain_utf8_to_alabel(host->name, NULL);
+#else
+    host->name;
+#endif
+  DEBUG(D_tls)
+    debug_printf("TLS: server cert verification includes hostname: \"%s\".\n",
+                   state->exp_tls_verify_cert_hostnames);
+  }
+}
+
+

 /*************************************************
 *    Start a TLS session in a client             *
 *************************************************/
 /*************************************************
 *    Start a TLS session in a client             *
 *************************************************/


@@ -1640,7 +1959,9 @@ Arguments:
   fd                the fd of the connection
   host              connected host (for messages)
   addr              the first address (not used)
   fd                the fd of the connection
   host              connected host (for messages)
   addr              the first address (not used)

-  ob                smtp transport options
+  tb                transport (always smtp)
+
+  errstr           error string pointer

 
 Returns:            OK/DEFER/FAIL (because using common functions),
                     but for a client, DEFER and FAIL have the same meaning
 
 Returns:            OK/DEFER/FAIL (because using common functions),
                     but for a client, DEFER and FAIL have the same meaning


@@ -1649,25 +1970,28 @@ Returns:            OK/DEFER/FAIL (because using common functions),
 int
 tls_client_start(int fd, host_item *host,
     address_item *addr ARG_UNUSED,
 int
 tls_client_start(int fd, host_item *host,
     address_item *addr ARG_UNUSED,

-    void *v_ob)
+    transport_instance * tb,
+#ifdef EXPERIMENTAL_DANE
+    dns_answer * tlsa_dnsa ARG_UNUSED,
+#endif
+    uschar ** errstr)

 {
 {

-smtp_transport_options_block *ob = v_ob;
+smtp_transport_options_block *ob =
+  (smtp_transport_options_block *)tb->options_block;

 int rc;
 int rc;

-const char *error;

 exim_gnutls_state_st *state = NULL;
 exim_gnutls_state_st *state = NULL;

-#ifdef EXPERIMENTAL_OCSP
-BOOL require_ocsp = verify_check_this_host(&ob->hosts_require_ocsp,
-  NULL, host->name, host->address, NULL) == OK;
+#ifndef DISABLE_OCSP
+BOOL require_ocsp =
+  verify_check_given_host(&ob->hosts_require_ocsp, host) == OK;

 BOOL request_ocsp = require_ocsp ? TRUE
 BOOL request_ocsp = require_ocsp ? TRUE

-  : verify_check_this_host(&ob->hosts_request_ocsp,
-      NULL, host->name, host->address, NULL) == OK;
+  : verify_check_given_host(&ob->hosts_request_ocsp, host) == OK;

 #endif
 
 DEBUG(D_tls) debug_printf("initialising GnuTLS as a client on fd %d\n", fd);
 
 if ((rc = tls_init(host, ob->tls_certificate, ob->tls_privatekey,
     ob->tls_sni, ob->tls_verify_certificates, ob->tls_crl,
 #endif
 
 DEBUG(D_tls) debug_printf("initialising GnuTLS as a client on fd %d\n", fd);
 
 if ((rc = tls_init(host, ob->tls_certificate, ob->tls_privatekey,
     ob->tls_sni, ob->tls_verify_certificates, ob->tls_crl,

-    ob->tls_require_ciphers, &state)) != OK)
+    ob->tls_require_ciphers, &state, errstr)) != OK)

   return rc;
 
   {
   return rc;
 
   {


@@ -1687,48 +2011,62 @@ if ((rc = tls_init(host, ob->tls_certificate, ob->tls_privatekey,
   gnutls_dh_set_prime_bits(state->session, dh_min_bits);
   }
 
   gnutls_dh_set_prime_bits(state->session, dh_min_bits);
   }
 

-/* Stick to the old behaviour for compatibility if tls_verify_certificates is 
+/* Stick to the old behaviour for compatibility if tls_verify_certificates is

 set but both tls_verify_hosts and tls_try_verify_hosts are unset. Check only
 the specified host patterns if one of them is defined */
 
 set but both tls_verify_hosts and tls_try_verify_hosts are unset. Check only
 the specified host patterns if one of them is defined */
 

-if ((  state->exp_tls_verify_certificates
-    && !ob->tls_verify_hosts
-    && !ob->tls_try_verify_hosts
-    )
-    ||
-    verify_check_host(&ob->tls_verify_hosts) == OK
+if (  (  state->exp_tls_verify_certificates
+      && !ob->tls_verify_hosts
+      && (!ob->tls_try_verify_hosts || !*ob->tls_try_verify_hosts)
+      )
+    || verify_check_given_host(&ob->tls_verify_hosts, host) == OK

    )
   {
    )
   {

-  DEBUG(D_tls) debug_printf("TLS: server certificate verification required.\n");
+  tls_client_setup_hostname_checks(host, state, ob);
+  DEBUG(D_tls)
+    debug_printf("TLS: server certificate verification required.\n");

   state->verify_requirement = VERIFY_REQUIRED;
   gnutls_certificate_server_set_request(state->session, GNUTLS_CERT_REQUIRE);
   }
   state->verify_requirement = VERIFY_REQUIRED;
   gnutls_certificate_server_set_request(state->session, GNUTLS_CERT_REQUIRE);
   }

-else if (verify_check_host(&ob->tls_try_verify_hosts) == OK)
+else if (verify_check_given_host(&ob->tls_try_verify_hosts, host) == OK)

   {
   {

-  DEBUG(D_tls) debug_printf("TLS: server certificate verification optional.\n");
+  tls_client_setup_hostname_checks(host, state, ob);
+  DEBUG(D_tls)
+    debug_printf("TLS: server certificate verification optional.\n");

   state->verify_requirement = VERIFY_OPTIONAL;
   gnutls_certificate_server_set_request(state->session, GNUTLS_CERT_REQUEST);
   }
 else
   {
   state->verify_requirement = VERIFY_OPTIONAL;
   gnutls_certificate_server_set_request(state->session, GNUTLS_CERT_REQUEST);
   }
 else
   {

-  DEBUG(D_tls) debug_printf("TLS: server certificate verification not required.\n");
+  DEBUG(D_tls)
+    debug_printf("TLS: server certificate verification not required.\n");

   state->verify_requirement = VERIFY_NONE;
   gnutls_certificate_server_set_request(state->session, GNUTLS_CERT_IGNORE);
   }
 
   state->verify_requirement = VERIFY_NONE;
   gnutls_certificate_server_set_request(state->session, GNUTLS_CERT_IGNORE);
   }
 

-#ifdef EXPERIMENTAL_OCSP       /* since GnuTLS 3.1.3 */
+#ifndef DISABLE_OCSP
+                       /* supported since GnuTLS 3.1.3 */

 if (request_ocsp)
   {
   DEBUG(D_tls) debug_printf("TLS: will request OCSP stapling\n");
   if ((rc = gnutls_ocsp_status_request_enable_client(state->session,
                    NULL, 0, NULL)) != OK)
     return tls_error(US"cert-status-req",
 if (request_ocsp)
   {
   DEBUG(D_tls) debug_printf("TLS: will request OCSP stapling\n");
   if ((rc = gnutls_ocsp_status_request_enable_client(state->session,
                    NULL, 0, NULL)) != OK)
     return tls_error(US"cert-status-req",

-                   gnutls_strerror(rc), state->host);
+                   gnutls_strerror(rc), state->host, errstr);

   tls_out.ocsp = OCSP_NOT_RESP;
   }
 #endif
 
   tls_out.ocsp = OCSP_NOT_RESP;
   }
 #endif
 

-gnutls_transport_set_ptr(state->session, (gnutls_transport_ptr)(long) fd);
+#ifndef DISABLE_EVENT
+if (tb->event_action)
+  {
+  state->event_action = tb->event_action;
+  gnutls_session_set_ptr(state->session, state);
+  gnutls_certificate_set_verify_function(state->x509_cred, verify_cb);
+  }
+#endif
+
+gnutls_transport_set_ptr(state->session, (gnutls_transport_ptr_t)(long) fd);

 state->fd_in = fd;
 state->fd_out = fd;
 
 state->fd_in = fd;
 state->fd_out = fd;
 


@@ -1745,18 +2083,23 @@ do
 alarm(0);
 
 if (rc != GNUTLS_E_SUCCESS)
 alarm(0);
 
 if (rc != GNUTLS_E_SUCCESS)

-  return tls_error(US"gnutls_handshake",
-      sigalrm_seen ? "timed out" : gnutls_strerror(rc), state->host);
+  if (sigalrm_seen)
+    {
+    gnutls_alert_send(state->session, GNUTLS_AL_FATAL, GNUTLS_A_USER_CANCELED);
+    return tls_error(US"gnutls_handshake", "timed out", state->host, errstr);
+    }
+  else
+    return tls_error(US"gnutls_handshake", gnutls_strerror(rc), state->host, errstr);

 
 DEBUG(D_tls) debug_printf("gnutls_handshake was successful\n");
 
 /* Verify late */
 
 if (state->verify_requirement != VERIFY_NONE &&
 
 DEBUG(D_tls) debug_printf("gnutls_handshake was successful\n");
 
 /* Verify late */
 
 if (state->verify_requirement != VERIFY_NONE &&

-    !verify_certificate(state, &error))
-  return tls_error(US"certificate verification failed", error, state->host);
+    !verify_certificate(state, errstr))
+  return tls_error(US"certificate verification failed", *errstr, state->host, errstr);

 
 

-#ifdef EXPERIMENTAL_OCSP
+#ifndef DISABLE_OCSP

 if (require_ocsp)
   {
   DEBUG(D_tls)
 if (require_ocsp)
   {
   DEBUG(D_tls)


@@ -1774,13 +2117,13 @@ if (require_ocsp)
       gnutls_free(printed.data);
       }
     else
       gnutls_free(printed.data);
       }
     else

-      (void) tls_error(US"ocsp decode", gnutls_strerror(rc), state->host);
+      (void) tls_error(US"ocsp decode", gnutls_strerror(rc), state->host, errstr);

     }
 
   if (gnutls_ocsp_status_request_is_checked(state->session, 0) == 0)
     {
     tls_out.ocsp = OCSP_FAILED;
     }
 
   if (gnutls_ocsp_status_request_is_checked(state->session, 0) == 0)
     {
     tls_out.ocsp = OCSP_FAILED;

-    return tls_error(US"certificate status check failed", NULL, state->host);
+    return tls_error(US"certificate status check failed", NULL, state->host, errstr);

     }
   DEBUG(D_tls) debug_printf("Passed OCSP checking\n");
   tls_out.ocsp = OCSP_VFIED;
     }
   DEBUG(D_tls) debug_printf("Passed OCSP checking\n");
   tls_out.ocsp = OCSP_VFIED;


@@ -1789,7 +2132,7 @@ if (require_ocsp)
 
 /* Figure out peer DN, and if authenticated, etc. */
 
 
 /* Figure out peer DN, and if authenticated, etc. */
 

-if ((rc = peer_status(state)) != OK)
+if ((rc = peer_status(state, errstr)) != OK)

   return rc;
 
 /* Sets various Exim expansion variables; may need to adjust for ACL callouts */
   return rc;
 
 /* Sets various Exim expansion variables; may need to adjust for ACL callouts */


@@ -1828,6 +2171,8 @@ if (shutdown)
   }
 
 gnutls_deinit(state->session);
   }
 
 gnutls_deinit(state->session);

+gnutls_certificate_free_credentials(state->x509_cred);
+

 
 state->tlsp->active = -1;
 memcpy(state, &exim_gnutls_state_init, sizeof(exim_gnutls_state_init));
 
 state->tlsp->active = -1;
 memcpy(state, &exim_gnutls_state_init, sizeof(exim_gnutls_state_init));


@@ -1837,12 +2182,80 @@ if ((state_server.session == NULL) && (state_client.session == NULL))
   gnutls_global_deinit();
   exim_gnutls_base_init_done = FALSE;
   }
   gnutls_global_deinit();
   exim_gnutls_base_init_done = FALSE;
   }

-

 }
 
 
 
 
 }
 
 
 
 

+static BOOL
+tls_refill(unsigned lim)
+{
+exim_gnutls_state_st * state = &state_server;
+ssize_t inbytes;
+
+DEBUG(D_tls) debug_printf("Calling gnutls_record_recv(%p, %p, %u)\n",
+  state->session, state->xfer_buffer, ssl_xfer_buffer_size);
+
+if (smtp_receive_timeout > 0) alarm(smtp_receive_timeout);
+inbytes = gnutls_record_recv(state->session, state->xfer_buffer,
+  MIN(ssl_xfer_buffer_size, lim));
+alarm(0);
+
+/* Timeouts do not get this far; see command_timeout_handler().
+   A zero-byte return appears to mean that the TLS session has been
+   closed down, not that the socket itself has been closed down. Revert to
+   non-TLS handling. */
+
+if (sigalrm_seen)
+  {
+  DEBUG(D_tls) debug_printf("Got tls read timeout\n");
+  state->xfer_error = 1;
+  return FALSE;
+  }
+
+else if (inbytes == 0)
+  {
+  DEBUG(D_tls) debug_printf("Got TLS_EOF\n");
+
+  receive_getc = smtp_getc;
+  receive_getbuf = smtp_getbuf;
+  receive_get_cache = smtp_get_cache;
+  receive_ungetc = smtp_ungetc;
+  receive_feof = smtp_feof;
+  receive_ferror = smtp_ferror;
+  receive_smtp_buffered = smtp_buffered;
+
+  gnutls_deinit(state->session);
+  gnutls_certificate_free_credentials(state->x509_cred);
+
+  state->session = NULL;
+  state->tlsp->active = -1;
+  state->tlsp->bits = 0;
+  state->tlsp->certificate_verified = FALSE;
+  tls_channelbinding_b64 = NULL;
+  state->tlsp->cipher = NULL;
+  state->tlsp->peercert = NULL;
+  state->tlsp->peerdn = NULL;
+
+  return FALSE;
+  }
+
+/* Handle genuine errors */
+
+else if (inbytes < 0)
+  {
+  record_io_error(state, (int) inbytes, US"recv", NULL);
+  state->xfer_error = 1;
+  return FALSE;
+  }
+#ifndef DISABLE_DKIM
+dkim_exim_verify_feed(state->xfer_buffer, inbytes);
+#endif
+state->xfer_buffer_hwm = (int) inbytes;
+state->xfer_buffer_lwm = 0;
+return TRUE;
+}
+

 /*************************************************
 *            TLS version of getc                 *
 *************************************************/
 /*************************************************
 *            TLS version of getc                 *
 *************************************************/


@@ -1853,71 +2266,65 @@ Only used by the server-side TLS.
 
 This feeds DKIM and should be used for all message-body reads.
 
 
 This feeds DKIM and should be used for all message-body reads.
 

-Arguments:  none
+Arguments:  lim                Maximum amount to read/bufffer

 Returns:    the next character or EOF
 */
 
 int
 Returns:    the next character or EOF
 */
 
 int

-tls_getc(void)
+tls_getc(unsigned lim)

 {
 {

-exim_gnutls_state_st *state = &state_server;
+exim_gnutls_state_st * state = &state_server;
+

 if (state->xfer_buffer_lwm >= state->xfer_buffer_hwm)
 if (state->xfer_buffer_lwm >= state->xfer_buffer_hwm)

-  {
-  ssize_t inbytes;
+  if (!tls_refill(lim))
+    return state->xfer_error ? EOF : smtp_getc(lim);

 
 

-  DEBUG(D_tls) debug_printf("Calling gnutls_record_recv(%p, %p, %u)\n",
-    state->session, state->xfer_buffer, ssl_xfer_buffer_size);
+/* Something in the buffer; return next uschar */

 
 

-  if (smtp_receive_timeout > 0) alarm(smtp_receive_timeout);
-  inbytes = gnutls_record_recv(state->session, state->xfer_buffer,
-    ssl_xfer_buffer_size);
-  alarm(0);
+return state->xfer_buffer[state->xfer_buffer_lwm++];
+}

 
 

-  /* A zero-byte return appears to mean that the TLS session has been
-     closed down, not that the socket itself has been closed down. Revert to
-     non-TLS handling. */
+uschar *
+tls_getbuf(unsigned * len)
+{
+exim_gnutls_state_st * state = &state_server;
+unsigned size;
+uschar * buf;

 
 

-  if (inbytes == 0)
+if (state->xfer_buffer_lwm >= state->xfer_buffer_hwm)
+  if (!tls_refill(*len))

     {
     {

-    DEBUG(D_tls) debug_printf("Got TLS_EOF\n");
-
-    receive_getc = smtp_getc;
-    receive_ungetc = smtp_ungetc;
-    receive_feof = smtp_feof;
-    receive_ferror = smtp_ferror;
-    receive_smtp_buffered = smtp_buffered;
-
-    gnutls_deinit(state->session);
-    state->session = NULL;
-    state->tlsp->active = -1;
-    state->tlsp->bits = 0;
-    state->tlsp->certificate_verified = FALSE;
-    tls_channelbinding_b64 = NULL;
-    state->tlsp->cipher = NULL;
-    state->tlsp->peercert = NULL;
-    state->tlsp->peerdn = NULL;
-
-    return smtp_getc();
+    if (!state->xfer_error) return smtp_getbuf(len);
+    *len = 0;
+    return NULL;

     }
 
     }
 

-  /* Handle genuine errors */
+if ((size = state->xfer_buffer_hwm - state->xfer_buffer_lwm) > *len)
+  size = *len;
+buf = &state->xfer_buffer[state->xfer_buffer_lwm];
+state->xfer_buffer_lwm += size;
+*len = size;
+return buf;
+}

 
 

-  else if (inbytes < 0)
-    {
-    record_io_error(state, (int) inbytes, US"recv", NULL);
-    state->xfer_error = 1;
-    return EOF;
-    }
+
+void
+tls_get_cache()
+{

 #ifndef DISABLE_DKIM
 #ifndef DISABLE_DKIM

-  dkim_exim_verify_feed(state->xfer_buffer, inbytes);
+exim_gnutls_state_st * state = &state_server;
+int n = state->xfer_buffer_hwm - state->xfer_buffer_lwm;
+if (n > 0)
+  dkim_exim_verify_feed(state->xfer_buffer+state->xfer_buffer_lwm, n);

 #endif
 #endif

-  state->xfer_buffer_hwm = (int) inbytes;
-  state->xfer_buffer_lwm = 0;
-  }
+}

 
 

-/* Something in the buffer; return next uschar */

 
 

-return state->xfer_buffer[state->xfer_buffer_lwm++];
+BOOL
+tls_could_read(void)
+{
+return state_server.xfer_buffer_lwm < state_server.xfer_buffer_hwm
+ || gnutls_record_check_pending(state_server.session) > 0;

 }
 
 
 }
 
 


@@ -1980,19 +2387,27 @@ Arguments:
   is_server channel specifier
   buff      buffer of data
   len       number of bytes
   is_server channel specifier
   buff      buffer of data
   len       number of bytes

+  more     more data expected soon

 
 Returns:    the number of bytes after a successful write,
             -1 after a failed write
 */
 
 int
 
 Returns:    the number of bytes after a successful write,
             -1 after a failed write
 */
 
 int

-tls_write(BOOL is_server, const uschar *buff, size_t len)
+tls_write(BOOL is_server, const uschar *buff, size_t len, BOOL more)

 {
 ssize_t outbytes;
 size_t left = len;
 exim_gnutls_state_st *state = is_server ? &state_server : &state_client;
 {
 ssize_t outbytes;
 size_t left = len;
 exim_gnutls_state_st *state = is_server ? &state_server : &state_client;

+#ifdef SUPPORT_CORK
+static BOOL corked = FALSE;
+
+if (more && !corked) gnutls_record_cork(state->session);
+#endif
+
+DEBUG(D_tls) debug_printf("%s(%p, " SIZE_T_FMT "%s)\n", __FUNCTION__,
+  buff, left, more ? ", more" : "");

 
 

-DEBUG(D_tls) debug_printf("tls_do_write(%p, " SIZE_T_FMT ")\n", buff, left);

 while (left > 0)
   {
   DEBUG(D_tls) debug_printf("gnutls_record_send(SSL, %p, " SIZE_T_FMT ")\n",
 while (left > 0)
   {
   DEBUG(D_tls) debug_printf("gnutls_record_send(SSL, %p, " SIZE_T_FMT ")\n",


@@ -2023,6 +2438,14 @@ if (len > INT_MAX)
   len = INT_MAX;
   }
 
   len = INT_MAX;
   }
 

+#ifdef SUPPORT_CORK
+if (more != corked)
+  {
+  if (!more) (void) gnutls_record_uncork(state->session, 0);
+  corked = more;
+  }
+#endif
+

 return (int) len;
 }
 
 return (int) len;
 }
 


@@ -2110,6 +2533,7 @@ int rc;
 uschar *expciphers = NULL;
 gnutls_priority_t priority_cache;
 const char *errpos;
 uschar *expciphers = NULL;
 gnutls_priority_t priority_cache;
 const char *errpos;

+uschar * dummy_errstr;

 
 #define validate_check_rc(Label) do { \
   if (rc != GNUTLS_E_SUCCESS) { if (exim_gnutls_base_init_done) gnutls_global_deinit(); \
 
 #define validate_check_rc(Label) do { \
   if (rc != GNUTLS_E_SUCCESS) { if (exim_gnutls_base_init_done) gnutls_global_deinit(); \


@@ -2134,7 +2558,8 @@ exim_gnutls_base_init_done = TRUE;
 if (!(tls_require_ciphers && *tls_require_ciphers))
   return_deinit(NULL);
 
 if (!(tls_require_ciphers && *tls_require_ciphers))
   return_deinit(NULL);
 

-if (!expand_check(tls_require_ciphers, US"tls_require_ciphers", &expciphers))
+if (!expand_check(tls_require_ciphers, US"tls_require_ciphers", &expciphers,
+                 &dummy_errstr))

   return_deinit(US"failed to expand tls_require_ciphers");
 
 if (!(expciphers && *expciphers))
   return_deinit(US"failed to expand tls_require_ciphers");
 
 if (!(expciphers && *expciphers))