* Exim - an Internet mail transport agent *
*************************************************/
-/* Copyright (c) University of Cambridge 1995 - 2012 */
+/* Copyright (c) University of Cambridge 1995 - 2014 */
/* See the file NOTICE for conditions of use and distribution. */
/* Copyright (c) Phil Pennock 2012 */
#if GNUTLS_VERSION_NUMBER >= 0x020c00
# include <gnutls/pkcs11.h>
#endif
+#ifdef EXPERIMENTAL_OCSP
+# include <gnutls/ocsp.h>
+#endif
/* GnuTLS 2 vs 3
#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 */
+#ifndef AVOID_GNUTLS_PKCS11
#define HAVE_GNUTLS_PKCS11
+#endif /* AVOID_GNUTLS_PKCS11 */
#endif
int cert_count;
/* We check for tls_sni *before* expansion. */
-if (!state->host)
+if (!host) /* server */
{
if (!state->received_sni)
{
if ((state->exp_tls_certificate == NULL) ||
(*state->exp_tls_certificate == '\0'))
{
- if (state->host == NULL)
+ if (!host)
return tls_error(US"no TLS server certificate is specified", NULL, NULL);
else
DEBUG(D_tls) debug_printf("TLS: no client certificate specified; okay\n");
DEBUG(D_tls) debug_printf("TLS: cert/key registered\n");
} /* tls_certificate */
+
+/* Set the OCSP stapling server info */
+
+#ifdef EXPERIMENTAL_OCSP
+if ( !host /* server */
+ && tls_ocsp_file
+ )
+ {
+ uschar * expanded;
+ int rc;
+
+ if (!expand_check(tls_ocsp_file, US"tls_ocsp_file", &expanded))
+ return DEFER;
+
+ /* Lazy way; would like callback to emit debug on actual response */
+
+ rc = gnutls_certificate_set_ocsp_status_request_file(state->x509_cred,
+ expanded, 0);
+ exim_gnutls_err_check(US"gnutls_certificate_set_ocsp_status_request_file");
+ DEBUG(D_tls) debug_printf("Set OCSP response file %s\n", expanded);
+ }
+#endif
+
+
/* Set the trusted CAs file if one is provided, and then add the CRL if one is
provided. Experiment shows that, if the certificate file is empty, an unhelpful
error message is provided. However, if we just refrain from setting anything up
by some sysadmin, but also means in common configurations that GNOME keyring
environment variables are used and so breaks for users calling mailq.
To prevent this, we init PKCS11 first, which is the documented approach. */
- if (!gnutls_enable_pkcs11)
+ if (!gnutls_allow_auto_pkcs11)
{
rc = gnutls_pkcs11_init(GNUTLS_PKCS11_FLAG_MANUAL, NULL);
exim_gnutls_err_check(US"gnutls_pkcs11_init");
"have an SNI set for a client [%s]\n", state->tls_sni);
/* This is the priority string support,
-http://www.gnu.org/software/gnutls/manual/html_node/Priority-Strings.html
+http://www.gnutls.org/manual/html_node/Priority-Strings.html
and replaces gnutls_require_kx, gnutls_require_mac & gnutls_require_protocols.
This was backwards incompatible, but means Exim no longer needs to track
all algorithms and provide string forms for them. */
*error = NULL;
-rc = peer_status(state);
-if (rc != OK)
+if ((rc = peer_status(state)) != OK)
{
verify = GNUTLS_CERT_INVALID;
- *error = "not supplied";
+ *error = "certificate not supplied";
}
else
- {
rc = gnutls_certificate_verify_peers2(state->session, &verify);
- }
/* 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)) != 0)
+if (rc < 0 || verify & (GNUTLS_CERT_INVALID|GNUTLS_CERT_REVOKED))
{
state->peer_cert_verified = FALSE;
- if (*error == NULL)
- *error = ((verify & GNUTLS_CERT_REVOKED) != 0) ? "revoked" : "invalid";
+ if (!*error)
+ *error = verify & GNUTLS_CERT_REVOKED
+ ? "certificate revoked" : "certificate invalid";
DEBUG(D_tls)
debug_printf("TLS certificate verification failed (%s): peerdn=%s\n",
fd the fd of the connection
host connected host (for messages)
addr the first address (not used)
- dhparam DH parameter file (ignored, we're a client)
certificate certificate file
privatekey private key file
sni TLS SNI to send to remote host
verify_certs file for certificate verify
verify_crl CRL for verify
require_ciphers list of allowed ciphers or NULL
+ hosts_require_ocsp hosts for which to request certificate-status (OCSP)
dh_min_bits minimum number of bits acceptable in server's DH prime
timeout startup timeout
+ verify_hosts mandatory client verification
+ try_verify_hosts optional client verification
Returns: OK/DEFER/FAIL (because using common functions),
but for a client, DEFER and FAIL have the same meaning
int
tls_client_start(int fd, host_item *host,
- address_item *addr ARG_UNUSED, uschar *dhparam ARG_UNUSED,
+ address_item *addr ARG_UNUSED,
uschar *certificate, uschar *privatekey, uschar *sni,
uschar *verify_certs, uschar *verify_crl,
- uschar *require_ciphers, int dh_min_bits, int timeout)
+ uschar *require_ciphers,
+#ifdef EXPERIMENTAL_OCSP
+ uschar *hosts_require_ocsp,
+#endif
+ int dh_min_bits, int timeout,
+ uschar *verify_hosts, uschar *try_verify_hosts)
{
int rc;
const char *error;
exim_gnutls_state_st *state = NULL;
+#ifdef EXPERIMENTAL_OCSP
+BOOL require_ocsp = verify_check_this_host(&hosts_require_ocsp,
+ NULL, host->name, host->address, NULL) == OK;
+#endif
DEBUG(D_tls) debug_printf("initialising GnuTLS as a client on fd %d\n", fd);
-rc = tls_init(host, certificate, privatekey,
- sni, verify_certs, verify_crl, require_ciphers, &state);
-if (rc != OK) return rc;
+if ((rc = tls_init(host, certificate, privatekey,
+ sni, verify_certs, verify_crl, require_ciphers, &state)) != OK)
+ return rc;
if (dh_min_bits < EXIM_CLIENT_DH_MIN_MIN_BITS)
{
dh_min_bits);
gnutls_dh_set_prime_bits(state->session, dh_min_bits);
-if (verify_certs == NULL)
+/* 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 */
+
+if (( state->exp_tls_verify_certificates
+ && !verify_hosts
+ && !try_verify_hosts
+ )
+ ||
+ verify_check_host(&verify_hosts) == OK
+ )
{
- DEBUG(D_tls) debug_printf("TLS: server certificate verification not required\n");
- state->verify_requirement = VERIFY_NONE;
- /* we still ask for it, to log it, etc */
+ 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);
+ }
+else if (verify_check_host(&try_verify_hosts) == OK)
+ {
+ 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
{
- 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);
+ 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);
}
+#ifdef EXPERIMENTAL_OCSP /* since GnuTLS 3.1.3 */
+if (require_ocsp &&
+ (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);
+#endif
+
gnutls_transport_set_ptr(state->session, (gnutls_transport_ptr)fd);
state->fd_in = fd;
state->fd_out = fd;
!verify_certificate(state, &error))
return tls_error(US"certificate verification failed", error, state->host);
+#ifdef EXPERIMENTAL_OCSP
+if (require_ocsp)
+ {
+ DEBUG(D_tls)
+ {
+ gnutls_datum_t stapling;
+ gnutls_ocsp_resp_t resp;
+ gnutls_datum_t printed;
+ if ( (rc= gnutls_ocsp_status_request_get(state->session, &stapling)) == 0
+ && (rc= gnutls_ocsp_resp_init(&resp)) == 0
+ && (rc= gnutls_ocsp_resp_import(resp, &stapling)) == 0
+ && (rc= gnutls_ocsp_resp_print(resp, GNUTLS_OCSP_PRINT_FULL, &printed)) == 0
+ )
+ {
+ fprintf(stderr, "%.4096s", printed.data);
+ gnutls_free(printed.data);
+ }
+ else
+ (void) tls_error(US"ocsp decode", gnutls_strerror(rc), state->host);
+ }
+
+ fprintf(stderr, "%s: checking ocsp\n", __FUNCTION__);
+ if (gnutls_ocsp_status_request_is_checked(state->session, 0) == 0)
+ return tls_error(US"certificate status check failed", NULL, state->host);
+ DEBUG(D_tls) debug_printf("Passed OCSP checking\n");
+ }
+#endif
+
/* 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; may need to adjust for ACL callouts */
"already initialised GnuTLS, Exim developer bug");
#ifdef HAVE_GNUTLS_PKCS11
-if (!gnutls_enable_pkcs11)
+if (!gnutls_allow_auto_pkcs11)
{
rc = gnutls_pkcs11_init(GNUTLS_PKCS11_FLAG_MANUAL, NULL);
validate_check_rc(US"gnutls_pkcs11_init");
gnutls_check_version(NULL));
}
+/* vi: aw ai sw=2
+*/
/* End of tls-gnu.c */
projects / user / henk / code / exim.git / blobdiff