+return 0;
+}
+
+/* Callback for handshake messages, on server */
+static int
+tls_server_hook_cb(gnutls_session_t sess, u_int htype, unsigned when,
+ unsigned incoming, const gnutls_datum_t * msg)
+{
+/* debug_printf("%s: htype %u\n", __FUNCTION__, htype); */
+switch (htype)
+ {
+# ifdef SUPPORT_GNUTLS_EXT_RAW_PARSE
+ case GNUTLS_HANDSHAKE_CLIENT_HELLO:
+ return tls_server_clienthello_cb(sess, htype, when, incoming, msg);
+ case GNUTLS_HANDSHAKE_CERTIFICATE_PKT:
+ return tls_server_servercerts_cb(sess, htype, when, incoming, msg);
+# endif
+ case GNUTLS_HANDSHAKE_CERTIFICATE_STATUS:
+ return tls_server_certstatus_cb(sess, htype, when, incoming, msg);
+# ifdef EXIM_HAVE_TLS_RESUME
+ case GNUTLS_HANDSHAKE_NEW_SESSION_TICKET:
+ return tls_server_ticket_cb(sess, htype, when, incoming, msg);
+# endif
+ default:
+ return 0;
+ }
+}
+#endif
+
+
+#if !defined(DISABLE_OCSP) && defined(SUPPORT_GNUTLS_EXT_RAW_PARSE)
+static void
+tls_server_testharness_ocsp_fiddle(void)
+{
+extern char ** environ;
+if (environ) for (uschar ** p = USS environ; *p; p++)
+ if (Ustrncmp(*p, "EXIM_TESTHARNESS_DISABLE_OCSPVALIDITYCHECK", 42) == 0)
+ {
+ DEBUG(D_tls) debug_printf("Permitting known bad OCSP response\n");
+ exim_testharness_disable_ocsp_validity_check = TRUE;
+ }
+}
+#endif
+
+/**************************************************
+* One-time init credentials for server and client *
+**************************************************/
+
+static void
+creds_basic_init(gnutls_certificate_credentials_t x509_cred, BOOL server)
+{
+#ifdef SUPPORT_SRV_OCSP_STACK
+gnutls_certificate_set_flags(x509_cred, GNUTLS_CERTIFICATE_API_V2);
+
+# if !defined(DISABLE_OCSP) && defined(SUPPORT_GNUTLS_EXT_RAW_PARSE)
+if (server && tls_ocsp_file)
+ {
+ if (f.running_in_test_harness)
+ tls_server_testharness_ocsp_fiddle();
+
+ if (exim_testharness_disable_ocsp_validity_check)
+ gnutls_certificate_set_flags(x509_cred,
+ GNUTLS_CERTIFICATE_API_V2 | GNUTLS_CERTIFICATE_SKIP_OCSP_RESPONSE_CHECK);
+ }
+# endif
+#endif
+DEBUG(D_tls)
+ debug_printf("TLS: basic cred init, %s\n", server ? "server" : "client");
+}
+
+static int
+creds_load_server_certs(exim_gnutls_state_st * state, const uschar * cert,
+ const uschar * pkey, const uschar * ocsp, uschar ** errstr)
+{
+const uschar * clist = cert;
+const uschar * klist = pkey;
+const uschar * olist;
+int csep = 0, ksep = 0, osep = 0, cnt = 0, rc;
+uschar * cfile, * kfile, * ofile;
+#ifndef DISABLE_OCSP
+# ifdef SUPPORT_GNUTLS_EXT_RAW_PARSE
+gnutls_x509_crt_fmt_t ocsp_fmt = GNUTLS_X509_FMT_DER;
+# endif
+
+if (!expand_check(ocsp, US"tls_ocsp_file", &ofile, errstr))
+ return DEFER;
+olist = ofile;
+#endif
+
+while (cfile = string_nextinlist(&clist, &csep, NULL, 0))
+
+ if (!(kfile = string_nextinlist(&klist, &ksep, NULL, 0)))
+ return tls_error(US"cert/key setup: out of keys", NULL, NULL, errstr);
+ else if ((rc = tls_add_certfile(state, NULL, cfile, kfile, errstr)) > 0)
+ return rc;
+ else
+ {
+ int gnutls_cert_index = -rc;
+ DEBUG(D_tls) debug_printf("TLS: cert/key %d %s registered\n",
+ gnutls_cert_index, cfile);
+
+#ifndef DISABLE_OCSP
+ if (ocsp)
+ {
+ /* Set the OCSP stapling server info */
+ if (gnutls_buggy_ocsp)
+ {
+ DEBUG(D_tls)
+ debug_printf("GnuTLS library is buggy for OCSP; avoiding\n");
+ }
+ else if ((ofile = string_nextinlist(&olist, &osep, NULL, 0)))
+ {
+ DEBUG(D_tls) debug_printf("OCSP response file %d = %s\n",
+ gnutls_cert_index, ofile);
+# ifdef SUPPORT_GNUTLS_EXT_RAW_PARSE
+ if (Ustrncmp(ofile, US"PEM ", 4) == 0)
+ {
+ ocsp_fmt = GNUTLS_X509_FMT_PEM;
+ ofile += 4;
+ }
+ else if (Ustrncmp(ofile, US"DER ", 4) == 0)
+ {
+ ocsp_fmt = GNUTLS_X509_FMT_DER;
+ ofile += 4;
+ }
+
+ if ((rc = gnutls_certificate_set_ocsp_status_request_file2(
+ state->lib_state.x509_cred, CCS ofile, gnutls_cert_index,
+ ocsp_fmt)) < 0)
+ return tls_error_gnu(
+ US"gnutls_certificate_set_ocsp_status_request_file2",
+ rc, NULL, errstr);
+ DEBUG(D_tls)
+ debug_printf(" %d response%s loaded\n", rc, rc>1 ? "s":"");
+
+ /* Arrange callbacks for OCSP request observability */
+
+ if (state->session)
+ gnutls_handshake_set_hook_function(state->session,
+ GNUTLS_HANDSHAKE_ANY, GNUTLS_HOOK_POST, tls_server_hook_cb);
+ else
+ state->lib_state.ocsp_hook = TRUE;
+
+
+# else
+# if defined(SUPPORT_SRV_OCSP_STACK)
+ if ((rc = gnutls_certificate_set_ocsp_status_request_function2(
+ state->lib_state.x509_cred, gnutls_cert_index,
+ server_ocsp_stapling_cb, ofile)))
+ return tls_error_gnu(
+ US"gnutls_certificate_set_ocsp_status_request_function2",
+ rc, NULL, errstr);
+ else
+# endif
+ {
+ if (cnt++ > 0)
+ {
+ DEBUG(D_tls)
+ debug_printf("oops; multiple OCSP files not supported\n");
+ break;
+ }
+ gnutls_certificate_set_ocsp_status_request_function(
+ state->lib_state.x509_cred, server_ocsp_stapling_cb, ofile);
+ }
+# endif /* SUPPORT_GNUTLS_EXT_RAW_PARSE */
+ }
+ else
+ DEBUG(D_tls) debug_printf("ran out of OCSP response files in list\n");
+ }
+#endif /* DISABLE_OCSP */
+ }
+return 0;
+}
+
+static int
+creds_load_client_certs(exim_gnutls_state_st * state, const host_item * host,
+ const uschar * cert, const uschar * pkey, uschar ** errstr)
+{
+int rc = tls_add_certfile(state, host, cert, pkey, errstr);
+if (rc > 0) return rc;
+DEBUG(D_tls) debug_printf("TLS: cert/key registered\n");
+return 0;
+}
+
+static int
+creds_load_cabundle(exim_gnutls_state_st * state, const uschar * bundle,
+ const host_item * host, uschar ** errstr)
+{
+int cert_count;
+struct stat statbuf;
+
+#ifdef SUPPORT_SYSDEFAULT_CABUNDLE
+if (Ustrcmp(bundle, "system") == 0 || Ustrncmp(bundle, "system,", 7) == 0)
+ cert_count = gnutls_certificate_set_x509_system_trust(state->lib_state.x509_cred);
+else
+#endif
+ {
+ if (Ustat(bundle, &statbuf) < 0)
+ {
+ log_write(0, LOG_MAIN|LOG_PANIC, "could not stat '%s' "
+ "(tls_verify_certificates): %s", bundle, strerror(errno));
+ 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))
+ {
+ log_write(0, LOG_MAIN|LOG_PANIC,
+ "tls_verify_certificates \"%s\" is a directory", bundle);
+ return DEFER;
+ }
+#endif
+
+ DEBUG(D_tls) debug_printf("verify certificates = %s size=" OFF_T_FMT "\n",
+ bundle, 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;
+ }
+
+ cert_count =
+
+#ifdef SUPPORT_CA_DIR
+ (statbuf.st_mode & S_IFMT) == S_IFDIR
+ ?
+ gnutls_certificate_set_x509_trust_dir(state->lib_state.x509_cred,
+ CS bundle, GNUTLS_X509_FMT_PEM)
+ :
+#endif
+ gnutls_certificate_set_x509_trust_file(state->lib_state.x509_cred,
+ CS bundle, GNUTLS_X509_FMT_PEM);
+
+#ifdef SUPPORT_CA_DIR
+ /* Mimic the behaviour with OpenSSL of not advertising a usable-cert list
+ when using the directory-of-certs config model. */
+
+ if ((statbuf.st_mode & S_IFMT) == S_IFDIR)
+ if (state->session)
+ gnutls_certificate_send_x509_rdn_sequence(state->session, 1);
+ else
+ state->lib_state.ca_rdn_emulate = TRUE;
+#endif
+ }
+
+if (cert_count < 0)
+ return tls_error_gnu(US"setting certificate trust", cert_count, host, errstr);
+DEBUG(D_tls)
+ debug_printf("Added %d certificate authorities\n", cert_count);
+
+return OK;
+}
+
+
+static int
+creds_load_crl(exim_gnutls_state_st * state, const uschar * crl, uschar ** errstr)
+{
+int cert_count;
+DEBUG(D_tls) debug_printf("loading CRL file = %s\n", crl);
+if ((cert_count = gnutls_certificate_set_x509_crl_file(state->lib_state.x509_cred,
+ CS crl, GNUTLS_X509_FMT_PEM)) < 0)
+ return tls_error_gnu(US"gnutls_certificate_set_x509_crl_file",
+ cert_count, state->host, errstr);
+
+DEBUG(D_tls) debug_printf("Processed %d CRLs\n", cert_count);
+return OK;
+}
+
+
+static int
+creds_load_pristring(exim_gnutls_state_st * state, const uschar * p,
+ const char ** errpos)
+{
+if (!p)
+ {
+ p = exim_default_gnutls_priority;
+ DEBUG(D_tls)
+ debug_printf("GnuTLS using default session cipher/priority \"%s\"\n", p);
+ }
+return gnutls_priority_init( (gnutls_priority_t *) &state->lib_state.pri_cache,
+ CCS p, errpos);
+}
+
+static void
+tls_server_creds_init(void)
+{
+uschar * dummy_errstr;
+
+state_server.lib_state = null_tls_preload;
+if (gnutls_certificate_allocate_credentials(
+ (gnutls_certificate_credentials_t *) &state_server.lib_state.x509_cred))
+ {
+ state_server.lib_state.x509_cred = NULL;
+ return;
+ }
+creds_basic_init(state_server.lib_state.x509_cred, TRUE);
+
+#ifdef EXIM_HAVE_INOTIFY
+/* If tls_certificate has any $ indicating expansions, it is not good.
+If tls_privatekey is set but has $, not good. Likewise for tls_ocsp_file.
+If all good (and tls_certificate set), load the cert(s). Do not try
+to handle selfsign generation for now (tls_certificate null/empty;
+XXX will want to do that later though) due to the lifetime/expiry issue. */
+
+if ( opt_set_and_noexpand(tls_certificate)
+ && opt_unset_or_noexpand(tls_privatekey)
+ && opt_unset_or_noexpand(tls_ocsp_file))
+ {
+ /* Set watches on the filenames. The implementation does de-duplication
+ so we can just blindly do them all.
+ */
+
+ if ( tls_set_watch(tls_certificate, TRUE)
+ && tls_set_watch(tls_privatekey, TRUE)
+ && tls_set_watch(tls_ocsp_file, TRUE)
+ )
+ {
+ DEBUG(D_tls) debug_printf("TLS: preloading server certs\n");
+ if (creds_load_server_certs(&state_server, tls_certificate,
+ tls_privatekey && *tls_privatekey ? tls_privatekey : tls_certificate,
+ tls_ocsp_file, &dummy_errstr) == 0)
+ state_server.lib_state.conn_certs = TRUE;
+ }
+ }
+else
+ DEBUG(D_tls) debug_printf("TLS: not preloading server certs\n");
+
+/* If tls_verify_certificates is non-empty and has no $, load CAs */
+
+if (opt_set_and_noexpand(tls_verify_certificates))
+ {
+ if (tls_set_watch(tls_verify_certificates, FALSE))
+ {
+ DEBUG(D_tls) debug_printf("TLS: preloading CA bundle for server\n");
+ if (creds_load_cabundle(&state_server, tls_verify_certificates,
+ NULL, &dummy_errstr) != OK)
+ return;
+ state_server.lib_state.cabundle = TRUE;
+
+ /* If CAs loaded and tls_crl is non-empty and has no $, load it */
+
+ if (opt_set_and_noexpand(tls_crl))
+ {
+ if (tls_set_watch(tls_crl, FALSE))
+ {
+ DEBUG(D_tls) debug_printf("TLS: preloading CRL for server\n");
+ if (creds_load_crl(&state_server, tls_crl, &dummy_errstr) != OK)
+ return;
+ state_server.lib_state.crl = TRUE;
+ }
+ }
+ else
+ DEBUG(D_tls) debug_printf("TLS: not preloading CRL for server\n");
+ }
+ }
+else
+ DEBUG(D_tls) debug_printf("TLS: not preloading CA bundle for server\n");
+#endif /* EXIM_HAVE_INOTIFY */
+
+/* If tls_require_ciphers is non-empty and has no $, load the
+ciphers priority cache. If unset, load with the default.
+(server-only as the client one depends on non/DANE) */
+
+if (!tls_require_ciphers || opt_set_and_noexpand(tls_require_ciphers))
+ {
+ const char * dummy_errpos;
+ DEBUG(D_tls) debug_printf("TLS: preloading cipher list for server: %s\n",
+ tls_require_ciphers);
+ if ( creds_load_pristring(&state_server, tls_require_ciphers, &dummy_errpos)
+ == OK)
+ state_server.lib_state.pri_string = TRUE;
+ }
+else
+ DEBUG(D_tls) debug_printf("TLS: not preloading cipher list for server\n");
+}
+
+
+/* Preload whatever creds are static, onto a transport. The client can then
+just copy the pointer as it starts up. */
+
+static void
+tls_client_creds_init(transport_instance * t, BOOL watch)
+{
+smtp_transport_options_block * ob = t->options_block;
+exim_gnutls_state_st tpt_dummy_state;
+host_item * dummy_host = (host_item *)1;
+uschar * dummy_errstr;
+
+if (!exim_gnutls_base_init_done)
+ tls_g_init();
+
+ob->tls_preload = null_tls_preload;
+if (gnutls_certificate_allocate_credentials(
+ (struct gnutls_certificate_credentials_st **)&ob->tls_preload.x509_cred))
+ {
+ ob->tls_preload.x509_cred = NULL;
+ return;
+ }
+creds_basic_init(ob->tls_preload.x509_cred, FALSE);
+
+tpt_dummy_state.session = NULL;
+tpt_dummy_state.lib_state = ob->tls_preload;
+
+#ifdef EXIM_HAVE_INOTIFY
+if ( opt_set_and_noexpand(ob->tls_certificate)
+ && opt_unset_or_noexpand(ob->tls_privatekey))
+ {
+ if ( !watch
+ || ( tls_set_watch(ob->tls_certificate, FALSE)
+ && tls_set_watch(ob->tls_privatekey, FALSE)
+ ) )
+ {
+ const uschar * pkey = ob->tls_privatekey;
+
+ DEBUG(D_tls)
+ debug_printf("TLS: preloading client certs for transport '%s'\n", t->name);
+
+ /* The state->lib_state.x509_cred is used for the certs load, and is the sole
+ structure element used. So we can set up a dummy. The hoat arg only
+ selects a retcode in case of fail, so any value */
+
+ if (creds_load_client_certs(&tpt_dummy_state, dummy_host,
+ ob->tls_certificate, pkey ? pkey : ob->tls_certificate,
+ &dummy_errstr) == OK)
+ ob->tls_preload.conn_certs = TRUE;
+ }
+ }
+else
+ DEBUG(D_tls)
+ debug_printf("TLS: not preloading client certs, for transport '%s'\n", t->name);
+
+if (opt_set_and_noexpand(ob->tls_verify_certificates))
+ {
+ if (!watch || tls_set_watch(ob->tls_verify_certificates, FALSE))
+ {
+ DEBUG(D_tls)
+ debug_printf("TLS: preloading CA bundle for transport '%s'\n", t->name);
+ if (creds_load_cabundle(&tpt_dummy_state, ob->tls_verify_certificates,
+ dummy_host, &dummy_errstr) != OK)
+ return;
+ ob->tls_preload.cabundle = TRUE;
+
+ if (opt_set_and_noexpand(ob->tls_crl))
+ {
+ if (!watch || tls_set_watch(ob->tls_crl, FALSE))
+ {
+ DEBUG(D_tls) debug_printf("TLS: preloading CRL for transport '%s'\n", t->name);
+ if (creds_load_crl(&tpt_dummy_state, ob->tls_crl, &dummy_errstr) != OK)
+ return;
+ ob->tls_preload.crl = TRUE;
+ }
+ }
+ else
+ DEBUG(D_tls) debug_printf("TLS: not preloading CRL, for transport '%s'\n", t->name);
+ }
+ }
+else
+ DEBUG(D_tls)
+ debug_printf("TLS: not preloading CA bundle, for transport '%s'\n", t->name);
+
+/* We do not preload tls_require_ciphers to to the transport as it implicitly
+depends on DANE or plain usage. */
+
+#endif
git://git.exim.org / users / heiko / exim.git / commitdiff