Merge from master into 4.next

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

diff --git a/src/src/tls-gnu.c b/src/src/tls-gnu.c
index 601197475c71ca424f372f7e236ba3a29529779b..10bfaca32ecf888f9c1e65ecf1ff13fe66c872b7 100644 (file)
--- a/src/src/tls-gnu.c
+++ b/src/src/tls-gnu.c
@@ -42,6 +42,7 @@ 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
 #if GNUTLS_VERSION_NUMBER < 0x030103 && !defined(DISABLE_OCSP)
 # warning "GnuTLS library version too old; define DISABLE_OCSP in Makefile"
 #endif
 #if GNUTLS_VERSION_NUMBER < 0x030103 && !defined(DISABLE_OCSP)
 # warning "GnuTLS library version too old; define DISABLE_OCSP in Makefile"


@@ -492,8 +493,7 @@ 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)
+  if (!(m.data = US std_dh_prime_named(exp_tls_dhparam)))

     return tls_error(US"No standard prime named", CS exp_tls_dhparam, NULL);
   m.size = Ustrlen(m.data);
   }
     return tls_error(US"No standard prime named", CS exp_tls_dhparam, NULL);
   m.size = Ustrlen(m.data);
   }


@@ -547,8 +547,7 @@ if (use_file_in_spool)
 /* Open the cache file for reading and if successful, read it and set up the
 parameters. */
 
 /* 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;


@@ -565,8 +564,7 @@ if (fd >= 0)
     (void)close(fd);
     return tls_error(US"TLS cache not a file", NULL, NULL);
     }
     (void)close(fd);
     return tls_error(US"TLS cache not a file", NULL, NULL);
     }

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

     {
     saved_errno = errno;
     (void)close(fd);
     {
     saved_errno = errno;
     (void)close(fd);


@@ -575,14 +573,12 @@ if (fd >= 0)
     }
 
   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);
     return tls_error(US"malloc failed", strerror(errno), NULL);
     }
     {
     fclose(fp);
     return tls_error(US"malloc failed", strerror(errno), NULL);
     }

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

     {
     saved_errno = errno;
     fclose(fp);
     {
     saved_errno = errno;
     fclose(fp);


@@ -626,8 +622,7 @@ if (rc < 0)
         CS filename, NULL);
 
   temp_fn = string_copy(US "%s.XXXXXXX");
         CS filename, NULL);
 
   temp_fn = string_copy(US "%s.XXXXXXX");

-  fd = mkstemp(CS temp_fn); /* modifies temp_fn */
-  if (fd < 0)
+  if ((fd = mkstemp(CS temp_fn)) < 0)  /* modifies temp_fn */

     return tls_error(US"Unable to open temp file", strerror(errno), NULL);
   (void)fchown(fd, exim_uid, exim_gid);   /* Probably not necessary */
 
     return tls_error(US"Unable to open temp file", strerror(errno), NULL);
   (void)fchown(fd, exim_uid, exim_gid);   /* Probably not necessary */
 


@@ -664,9 +659,9 @@ 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)
+  if (!(m.data = malloc(m.size)))

     return tls_error(US"memory allocation failed", strerror(errno), NULL);
     return tls_error(US"memory allocation failed", strerror(errno), NULL);

+

   /* 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);


@@ -677,23 +672,19 @@ 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",
         strerror(errno), NULL);
     }
   free(m.data);
     {
     free(m.data);
     return tls_error(US"TLS cache write D-H params failed",
         strerror(errno), NULL);
     }
   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",
         strerror(errno), NULL);
 
     return tls_error(US"TLS cache write D-H params final newline failed",
         strerror(errno), NULL);
 

-  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);

 
   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\"",


@@ -709,6 +700,74 @@ return OK;
 
 
 
 
 
 

+/* Create and install a selfsigned certificate, for use in server mode */
+
+static int
+tls_install_selfsign(exim_gnutls_state_st * state)
+{
+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);
+  goto out;
+}
+
+
+
+

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


@@ -741,7 +800,6 @@ 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 &&


@@ -762,7 +820,6 @@ 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");


@@ -779,14 +836,13 @@ if (!expand_check_tlsvar(tls_certificate))
 
 /* certificate is mandatory in server, optional in client */
 
 
 /* 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);

   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))
   return DEFER;
 
 if (state->tls_privatekey && !expand_check_tlsvar(tls_privatekey))
   return DEFER;


@@ -806,9 +862,9 @@ 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");
       }


@@ -816,7 +872,6 @@ 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,


@@ -911,7 +966,7 @@ else
   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.
   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 ... */
+  So s/!S_ISREG/S_ISDIR/ and change some messaging ... */

   if (S_ISDIR(statbuf.st_mode))
     {
     DEBUG(D_tls)
   if (S_ISDIR(statbuf.st_mode))
     {
     DEBUG(D_tls)


@@ -1448,7 +1503,7 @@ else
     int sep = 0;
     const uschar * list = state->exp_tls_verify_cert_hostnames;
     uschar * name;
     int sep = 0;
     const uschar * list = state->exp_tls_verify_cert_hostnames;
     uschar * name;

-    while (name = string_nextinlist(&list, &sep, NULL, 0))
+    while ((name = string_nextinlist(&list, &sep, NULL, 0)))

       if (gnutls_x509_crt_check_hostname(state->tlsp->peercert, CS name))
        break;
     if (!name)
       if (gnutls_x509_crt_check_hostname(state->tlsp->peercert, CS name))
        break;
     if (!name)


@@ -1761,24 +1816,33 @@ state->fd_out = fileno(smtp_out);
 sigalrm_seen = FALSE;
 if (smtp_receive_timeout > 0) alarm(smtp_receive_timeout);
 do
 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);
+    gnutls_db_remove_session(state->session);
+    }
+  else

     {
     {

+    tls_error(US"gnutls_handshake", gnutls_strerror(rc), NULL);
+    (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;


@@ -1803,8 +1867,7 @@ if (  state->verify_requirement != VERIFY_NONE
 
 /* 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)) != OK) return rc;

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


@@ -1816,6 +1879,7 @@ 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_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;


@@ -1867,7 +1931,7 @@ tls_client_start(int fd, host_item *host,
     address_item *addr ARG_UNUSED,
     transport_instance *tb
 #ifdef EXPERIMENTAL_DANE
     address_item *addr ARG_UNUSED,
     transport_instance *tb
 #ifdef EXPERIMENTAL_DANE

-    , dne_answer * unused_tlsa_dnsa
+    , dns_answer * unused_tlsa_dnsa

 #endif
     )
 {
 #endif
     )
 {


@@ -1979,8 +2043,13 @@ 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);
+    }
+  else
+    return tls_error(US"gnutls_handshake", gnutls_strerror(rc), state->host);

 
 DEBUG(D_tls) debug_printf("gnutls_handshake was successful\n");
 
 
 DEBUG(D_tls) debug_printf("gnutls_handshake was successful\n");
 


@@ -2062,6 +2131,8 @@ 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));


@@ -2107,21 +2178,32 @@ if (state->xfer_buffer_lwm >= state->xfer_buffer_hwm)
     ssl_xfer_buffer_size);
   alarm(0);
 
     ssl_xfer_buffer_size);
   alarm(0);
 

-  /* A zero-byte return appears to mean that the TLS session has been
+  /* 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. */
 
      closed down, not that the socket itself has been closed down. Revert to
      non-TLS handling. */
 

-  if (inbytes == 0)
+  if (sigalrm_seen)
+    {
+    DEBUG(D_tls) debug_printf("Got tls read timeout\n");
+    state->xfer_error = 1;
+    return EOF;
+    }
+
+  else if (inbytes == 0)

     {
     DEBUG(D_tls) debug_printf("Got TLS_EOF\n");
 
     receive_getc = smtp_getc;
     {
     DEBUG(D_tls) debug_printf("Got TLS_EOF\n");
 
     receive_getc = smtp_getc;

+    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);
     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->session = NULL;
     state->tlsp->active = -1;
     state->tlsp->bits = 0;


@@ -2154,6 +2236,17 @@ if (state->xfer_buffer_lwm >= state->xfer_buffer_hwm)
 return state->xfer_buffer[state->xfer_buffer_lwm++];
 }
 
 return state->xfer_buffer[state->xfer_buffer_lwm++];
 }
 

+void
+tls_get_cache()
+{
+#ifndef DISABLE_DKIM
+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
+}
+