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[exim.git] / src / src / tls-gnu.c
index 7364a66ff540ab2a9056c443886e5674ce287948..0774850cae8f77947c2e72a02ecbb136f9c6c8fa 100644 (file)
@@ -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>
+# 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"
@@ -413,7 +414,7 @@ if (rc) {
 } 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");
 }
@@ -709,6 +710,74 @@ 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           *
 *************************************************/
@@ -741,7 +810,6 @@ int cert_count;
 
 /* We check for tls_sni *before* expansion. */
 if (!host)     /* server */
-  {
   if (!state->received_sni)
     {
     if (state->tls_certificate &&
@@ -762,7 +830,6 @@ if (!host)  /* server */
     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");
@@ -779,14 +846,13 @@ if (!expand_check_tlsvar(tls_certificate))
 
 /* 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)
-    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");
-  }
 
 if (state->tls_privatekey && !expand_check_tlsvar(tls_privatekey))
   return DEFER;
@@ -806,9 +872,9 @@ if (state->exp_tls_certificate && *state->exp_tls_certificate)
       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");
       }
@@ -816,7 +882,6 @@ if (state->exp_tls_certificate && *state->exp_tls_certificate)
       {
       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,
@@ -911,7 +976,7 @@ 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.
-  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)
@@ -1448,7 +1513,7 @@ else
     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)
@@ -1761,10 +1826,8 @@ state->fd_out = fileno(smtp_out);
 sigalrm_seen = FALSE;
 if (smtp_receive_timeout > 0) alarm(smtp_receive_timeout);
 do
-  {
   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)
@@ -1816,6 +1879,7 @@ and initialize appropriately. */
 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;
@@ -1867,7 +1931,7 @@ tls_client_start(int fd, host_item *host,
     address_item *addr ARG_UNUSED,
     transport_instance *tb
 #ifdef EXPERIMENTAL_DANE
-    , dne_answer * unused_tlsa_dnsa
+    , dns_answer * unused_tlsa_dnsa
 #endif
     )
 {
@@ -2116,6 +2180,7 @@ if (state->xfer_buffer_lwm >= state->xfer_buffer_hwm)
     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;
@@ -2154,6 +2219,17 @@ if (state->xfer_buffer_lwm >= state->xfer_buffer_hwm)
 return state->xfer_buffer[state->xfer_buffer_lwm++];
 }
 
+#ifndef DISABLE_DKIM
+void
+tls_get_cache()
+{
+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
+