int fd_out;
BOOL peer_cert_verified;
BOOL trigger_sni_changes;
+ BOOL have_set_peerdn;
const struct host_item *host;
uschar *peerdn;
+ uschar *ciphersuite;
uschar *received_sni;
const uschar *tls_certificate;
int xfer_buffer_hwm;
int xfer_eof;
int xfer_error;
-
- uschar cipherbuf[256];
} exim_gnutls_state_st;
static const exim_gnutls_state_st exim_gnutls_state_init = {
- NULL, NULL, NULL, VERIFY_NONE, -1, -1, FALSE, FALSE,
- NULL, NULL, NULL,
+ 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, 0, 0, 0, 0,
- ""
};
/* Not only do we have our own APIs which don't pass around state, assuming
static void
extract_exim_vars_from_tls_state(exim_gnutls_state_st *state)
{
-gnutls_protocol_t protocol;
gnutls_cipher_algorithm_t cipher;
-gnutls_kx_algorithm_t kx;
-gnutls_mac_algorithm_t mac;
-uschar *p;
#ifdef HAVE_GNUTLS_SESSION_CHANNEL_BINDING
int old_pool;
int rc;
/* returns size in "bytes" */
tls_bits = gnutls_cipher_get_key_size(cipher) * 8;
-if (!*state->cipherbuf)
- {
- protocol = gnutls_protocol_get_version(state->session);
- mac = gnutls_mac_get(state->session);
- kx = gnutls_kx_get(state->session);
-
- string_format(state->cipherbuf, sizeof(state->cipherbuf),
- "%s:%s:%u",
- gnutls_protocol_get_name(protocol),
- gnutls_cipher_suite_get_name(kx, cipher, mac),
- tls_bits);
-
- /* I don't see a way that spaces could occur, in the current GnuTLS
- code base, but it was a concern in the old code and perhaps older GnuTLS
- releases did return "TLS 1.0"; play it safe, just in case. */
- for (p = state->cipherbuf; *p != '\0'; ++p)
- if (isspace(*p))
- *p = '-';
- }
-tls_cipher = state->cipherbuf;
+tls_cipher = state->ciphersuite;
DEBUG(D_tls) debug_printf("cipher: %s\n", tls_cipher);
dh_bits);
#endif
+/* Some clients have hard-coded limits. */
+if (dh_bits > tls_dh_max_bits)
+ {
+ DEBUG(D_tls)
+ debug_printf("tls_dh_max_bits clamping override, using %d bits instead.\n",
+ tls_dh_max_bits);
+ dh_bits = tls_dh_max_bits;
+ }
+
if (!string_format(filename, sizeof(filename),
"%s/gnutls-params-%d", spool_directory, dh_bits))
return tls_error(US"overlong filename", NULL, NULL);
m.data = malloc(m.size);
if (m.data == NULL)
return tls_error(US"memory allocation failed", strerror(errno), NULL);
+ /* this will return a size 1 less than the allocation size above; I
+ originally used sz so as to avoid type compatibility errors, as gnutls_datum
+ uses "unsigned int" for the size field, but this call takes separate data
+ and size fields, with the latter being a size_t*. For now, we live with
+ the error as being safer than throwing away type information. */
rc = gnutls_dh_params_export_pkcs3(dh_server_params, GNUTLS_X509_FMT_PEM,
- m.data, &sz);
+ m.data, &m.size);
if (rc != GNUTLS_E_SUCCESS)
{
free(m.data);
{
if (!state->received_sni)
{
- if (Ustrstr(state->tls_certificate, US"tls_sni"))
+ if (state->tls_certificate && Ustrstr(state->tls_certificate, US"tls_sni"))
{
DEBUG(D_tls) debug_printf("We will re-expand TLS session files if we receive SNI.\n");
state->trigger_sni_changes = TRUE;
return DEFER;
}
-if (!S_ISREG(statbuf.st_mode))
+/* 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 not a file: \"%s\"\n%s\n",
- state->exp_tls_verify_certificates,
- S_ISDIR(statbuf.st_mode)
- ? " it's a directory, that's OpenSSL, this is GnuTLS"
- : " (not a directory either)");
+ 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 not a file",
+ "tls_verify_certificates \"%s\" is a directory",
state->exp_tls_verify_certificates);
return DEFER;
}
}
DEBUG(D_tls) debug_printf("Added %d certificate authorities.\n", cert_count);
-if (state->tls_crl && *state->tls_crl)
+if (state->tls_crl && *state->tls_crl &&
+ state->exp_tls_crl && *state->exp_tls_crl)
{
- if (state->exp_tls_crl && *state->exp_tls_crl)
+ DEBUG(D_tls) debug_printf("loading CRL file = %s\n", state->exp_tls_crl);
+ cert_count = gnutls_certificate_set_x509_crl_file(state->x509_cred,
+ CS state->exp_tls_crl, GNUTLS_X509_FMT_PEM);
+ if (cert_count < 0)
{
- DEBUG(D_tls) debug_printf("loading CRL file = %s\n", state->exp_tls_crl);
- rc = gnutls_certificate_set_x509_crl_file(state->x509_cred,
- CS state->exp_tls_crl, GNUTLS_X509_FMT_PEM);
+ rc = cert_count;
exim_gnutls_err_check(US"gnutls_certificate_set_x509_crl_file");
}
+ DEBUG(D_tls) debug_printf("Processed %d CRLs.\n", cert_count);
}
return OK;
state->tls_certificate = certificate;
state->tls_privatekey = privatekey;
+state->tls_require_ciphers = require_ciphers;
state->tls_sni = sni;
state->tls_verify_certificates = cas;
state->tls_crl = crl;
*************************************************/
/* Called from both server and client code.
-Only this is allowed to set state->peerdn and we use that to detect double-calls.
+Only this is allowed to set state->peerdn and state->have_set_peerdn
+and we use that to detect double-calls.
+
+NOTE: the state blocks last while the TLS connection is up, which is fine
+for logging in the server side, but for the client side, we log after teardown
+in src/deliver.c. While the session is up, we can twist about states and
+repoint tls_* globals, but those variables used for logging or other variable
+expansion that happens _after_ delivery need to have a longer life-time.
+
+So for those, we get the data from POOL_PERM; the re-invoke guard keeps us from
+doing this more than once per generation of a state context. We set them in
+the state context, and repoint tls_* to them. After the state goes away, the
+tls_* copies of the pointers remain valid and client delivery logging is happy.
+
+tls_certificate_verified is a BOOL, so the tls_peerdn and tls_cipher issues
+don't apply.
Arguments:
state exim_gnutls_state_st *
static int
peer_status(exim_gnutls_state_st *state)
{
+uschar cipherbuf[256];
const gnutls_datum *cert_list;
-int rc;
+int old_pool, rc;
unsigned int cert_list_size = 0;
+gnutls_protocol_t protocol;
+gnutls_cipher_algorithm_t cipher;
+gnutls_kx_algorithm_t kx;
+gnutls_mac_algorithm_t mac;
gnutls_certificate_type_t ct;
gnutls_x509_crt_t crt;
-uschar *dn_buf;
+uschar *p, *dn_buf;
size_t sz;
-if (state->peerdn)
+if (state->have_set_peerdn)
return OK;
+state->have_set_peerdn = TRUE;
+
+state->peerdn = NULL;
-state->peerdn = US"unknown";
+/* tls_cipher */
+cipher = gnutls_cipher_get(state->session);
+protocol = gnutls_protocol_get_version(state->session);
+mac = gnutls_mac_get(state->session);
+kx = gnutls_kx_get(state->session);
+
+string_format(cipherbuf, sizeof(cipherbuf),
+ "%s:%s:%d",
+ gnutls_protocol_get_name(protocol),
+ gnutls_cipher_suite_get_name(kx, cipher, mac),
+ (int) gnutls_cipher_get_key_size(cipher) * 8);
+
+/* I don't see a way that spaces could occur, in the current GnuTLS
+code base, but it was a concern in the old code and perhaps older GnuTLS
+releases did return "TLS 1.0"; play it safe, just in case. */
+for (p = cipherbuf; *p != '\0'; ++p)
+ if (isspace(*p))
+ *p = '-';
+old_pool = store_pool;
+store_pool = POOL_PERM;
+state->ciphersuite = string_copy(cipherbuf);
+store_pool = old_pool;
+tls_cipher = state->ciphersuite;
+/* tls_peerdn */
cert_list = gnutls_certificate_get_peers(state->session, &cert_list_size);
if (cert_list == NULL || cert_list_size == 0)
{
- state->peerdn = US"unknown (no certificate)";
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 (ct != GNUTLS_CRT_X509)
{
const char *ctn = gnutls_certificate_type_get_name(ct);
- state->peerdn = string_sprintf("unknown (type %s)", ctn);
DEBUG(D_tls)
debug_printf("TLS: peer cert not X.509 but instead \"%s\"\n", ctn);
if (state->verify_requirement == VERIFY_REQUIRED)
DEBUG(D_tls)
debug_printf("TLS certificate verification failed (%s): peerdn=%s\n",
- *error, state->peerdn);
+ *error, state->peerdn ? state->peerdn : US"<unset>");
if (state->verify_requirement == VERIFY_REQUIRED)
{
else
{
state->peer_cert_verified = TRUE;
- DEBUG(D_tls) debug_printf("TLS certificate verified: peerdn=%s\n", state->peerdn);
+ DEBUG(D_tls) debug_printf("TLS certificate verified: peerdn=%s\n",
+ state->peerdn ? state->peerdn : US"<unset>");
}
tls_peerdn = state->peerdn;
static void
exim_gnutls_logger_cb(int level, const char *message)
{
- DEBUG(D_tls) debug_printf("GnuTLS<%d>: %s\n", level, message);
+ size_t len = strlen(message);
+ if (len < 1)
+ {
+ DEBUG(D_tls) debug_printf("GnuTLS<%d> empty debug message\n", level);
+ return;
+ }
+ DEBUG(D_tls) debug_printf("GnuTLS<%d>: %s%s", level, message,
+ message[len-1] == '\n' ? "" : "\n");
}
#endif
do
{
rc = gnutls_handshake(state->session);
- } while ((rc == GNUTLS_E_AGAIN) || (rc == GNUTLS_E_INTERRUPTED));
+ } while ((rc == GNUTLS_E_AGAIN) ||
+ (rc == GNUTLS_E_INTERRUPTED && !sigalrm_seen));
alarm(0);
if (rc != GNUTLS_E_SUCCESS)
do
{
rc = gnutls_handshake(state->session);
- } while ((rc == GNUTLS_E_AGAIN) || (rc == GNUTLS_E_INTERRUPTED));
+ } while ((rc == GNUTLS_E_AGAIN) ||
+ (rc == GNUTLS_E_INTERRUPTED && !sigalrm_seen));
alarm(0);
+if (rc != GNUTLS_E_SUCCESS)
+ return tls_error(US"gnutls_handshake",
+ sigalrm_seen ? "timed out" : gnutls_strerror(rc), state->host);
+
DEBUG(D_tls) debug_printf("gnutls_handshake was successful\n");
/* Verify late */
rc = peer_status(state);
if (rc != OK) return rc;
-/* Sets various Exim expansion variables; always safe within server */
+/* Sets various Exim expansion variables; may need to adjust for ACL callouts */
extract_exim_vars_from_tls_state(state);
+/*************************************************
+* Let tls_require_ciphers be checked at startup *
+*************************************************/
+
+/* The tls_require_ciphers option, if set, must be something which the
+library can parse.
+
+Returns: NULL on success, or error message
+*/
+
+uschar *
+tls_validate_require_cipher(void)
+{
+int rc;
+uschar *expciphers = NULL;
+gnutls_priority_t priority_cache;
+const char *errpos;
+
+#define validate_check_rc(Label) do { \
+ if (rc != GNUTLS_E_SUCCESS) { if (exim_gnutls_base_init_done) gnutls_global_deinit(); \
+ return string_sprintf("%s failed: %s", (Label), gnutls_strerror(rc)); } } while (0)
+#define return_deinit(Label) do { gnutls_global_deinit(); return (Label); } while (0)
+
+if (exim_gnutls_base_init_done)
+ log_write(0, LOG_MAIN|LOG_PANIC,
+ "already initialised GnuTLS, Exim developer bug");
+
+rc = gnutls_global_init();
+validate_check_rc(US"gnutls_global_init()");
+exim_gnutls_base_init_done = TRUE;
+
+if (!(tls_require_ciphers && *tls_require_ciphers))
+ return_deinit(NULL);
+
+if (!expand_check(tls_require_ciphers, US"tls_require_ciphers", &expciphers))
+ return_deinit(US"failed to expand tls_require_ciphers");
+
+if (!(expciphers && *expciphers))
+ return_deinit(NULL);
+
+DEBUG(D_tls)
+ debug_printf("tls_require_ciphers expands to \"%s\"\n", expciphers);
+
+rc = gnutls_priority_init(&priority_cache, CS expciphers, &errpos);
+validate_check_rc(string_sprintf(
+ "gnutls_priority_init(%s) failed at offset %ld, \"%.8s..\"",
+ expciphers, errpos - CS expciphers, errpos));
+
+#undef return_deinit
+#undef validate_check_rc
+gnutls_global_deinit();
+
+return NULL;
+}
+
+
+
+
/*************************************************
* Report the library versions. *
*************************************************/
git://git.exim.org / exim.git / blobdiff