1 /***************************************************************************
3 * Project ___| | | | _ \| |
5 * | (__| |_| | _ <| |___
6 * \___|\___/|_| \_\_____|
8 * Copyright (C) 1998 - 2015, Daniel Stenberg, <daniel@haxx.se>, et al.
10 * This software is licensed as described in the file COPYING, which
11 * you should have received as part of this distribution. The terms
12 * are also available at http://curl.haxx.se/docs/copyright.html.
14 * You may opt to use, copy, modify, merge, publish, distribute and/or sell
15 * copies of the Software, and permit persons to whom the Software is
16 * furnished to do so, under the terms of the COPYING file.
18 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
19 * KIND, either express or implied.
21 ***************************************************************************/
24 * Source file for all GnuTLS-specific code for the TLS/SSL layer. No code
25 * but vtls.c should ever call or use these functions.
27 * Note: don't use the GnuTLS' *_t variable type names in this source code,
28 * since they were not present in 1.0.X.
31 #include "curl_setup.h"
35 #include <gnutls/abstract.h>
36 #include <gnutls/gnutls.h>
37 #include <gnutls/x509.h>
39 #ifdef USE_GNUTLS_NETTLE
40 #include <gnutls/crypto.h>
41 #include <nettle/md5.h>
48 #include "inet_pton.h"
51 #include "parsedate.h"
52 #include "connect.h" /* for the connect timeout */
57 #define _MPRINTF_REPLACE /* use our functions only */
58 #include <curl/mprintf.h>
59 #include "curl_memory.h"
60 /* The last #include file should be: */
64 Some hackish cast macros based on:
65 http://library.gnome.org/devel/glib/unstable/glib-Type-Conversion-Macros.html
67 #ifndef GNUTLS_POINTER_TO_INT_CAST
68 #define GNUTLS_POINTER_TO_INT_CAST(p) ((int) (long) (p))
70 #ifndef GNUTLS_INT_TO_POINTER_CAST
71 #define GNUTLS_INT_TO_POINTER_CAST(i) ((void*) (long) (i))
74 /* Enable GnuTLS debugging by defining GTLSDEBUG */
75 /*#define GTLSDEBUG */
78 static void tls_log_func(int level, const char *str)
80 fprintf(stderr, "|<%d>| %s", level, str);
83 static bool gtls_inited = FALSE;
85 #if defined(GNUTLS_VERSION_NUMBER)
86 # if (GNUTLS_VERSION_NUMBER >= 0x020c00)
87 # undef gnutls_transport_set_lowat
88 # define gnutls_transport_set_lowat(A,B) Curl_nop_stmt
89 # define USE_GNUTLS_PRIORITY_SET_DIRECT 1
91 # if (GNUTLS_VERSION_NUMBER >= 0x020c03)
92 # define GNUTLS_MAPS_WINSOCK_ERRORS 1
97 # if (GNUTLS_VERSION_NUMBER >= 0x030200)
102 # if (GNUTLS_VERSION_NUMBER >= 0x03020d)
108 # include <gnutls/ocsp.h>
112 * Custom push and pull callback functions used by GNU TLS to read and write
113 * to the socket. These functions are simple wrappers to send() and recv()
114 * (although here using the sread/swrite macros as defined by
115 * curl_setup_once.h).
116 * We use custom functions rather than the GNU TLS defaults because it allows
117 * us to get specific about the fourth "flags" argument, and to use arbitrary
118 * private data with gnutls_transport_set_ptr if we wish.
120 * When these custom push and pull callbacks fail, GNU TLS checks its own
121 * session-specific error variable, and when not set also its own global
122 * errno variable, in order to take appropriate action. GNU TLS does not
123 * require that the transport is actually a socket. This implies that for
124 * Windows builds these callbacks should ideally set the session-specific
125 * error variable using function gnutls_transport_set_errno or as a last
126 * resort global errno variable using gnutls_transport_set_global_errno,
127 * with a transport agnostic error value. This implies that some winsock
128 * error translation must take place in these callbacks.
130 * Paragraph above applies to GNU TLS versions older than 2.12.3, since
131 * this version GNU TLS does its own internal winsock error translation
132 * using system_errno() function.
135 #if defined(USE_WINSOCK) && !defined(GNUTLS_MAPS_WINSOCK_ERRORS)
136 # define gtls_EINTR 4
138 # define gtls_EAGAIN 11
139 static int gtls_mapped_sockerrno(void)
153 static ssize_t Curl_gtls_push(void *s, const void *buf, size_t len)
155 ssize_t ret = swrite(GNUTLS_POINTER_TO_INT_CAST(s), buf, len);
156 #if defined(USE_WINSOCK) && !defined(GNUTLS_MAPS_WINSOCK_ERRORS)
158 gnutls_transport_set_global_errno(gtls_mapped_sockerrno());
163 static ssize_t Curl_gtls_pull(void *s, void *buf, size_t len)
165 ssize_t ret = sread(GNUTLS_POINTER_TO_INT_CAST(s), buf, len);
166 #if defined(USE_WINSOCK) && !defined(GNUTLS_MAPS_WINSOCK_ERRORS)
168 gnutls_transport_set_global_errno(gtls_mapped_sockerrno());
175 * Global GnuTLS init, called from Curl_ssl_init(). This calls functions that
176 * are not thread-safe and thus this function itself is not thread-safe and
177 * must only be called from within curl_global_init() to keep the thread
178 * situation under control!
180 int Curl_gtls_init(void)
184 ret = gnutls_global_init()?0:1;
186 gnutls_global_set_log_function(tls_log_func);
187 gnutls_global_set_log_level(2);
194 int Curl_gtls_cleanup(void)
197 gnutls_global_deinit();
203 static void showtime(struct SessionHandle *data,
208 const struct tm *tm = &buffer;
209 CURLcode result = Curl_gmtime(stamp, &buffer);
213 snprintf(data->state.buffer,
215 "\t %s: %s, %02d %s %4d %02d:%02d:%02d GMT\n",
217 Curl_wkday[tm->tm_wday?tm->tm_wday-1:6],
219 Curl_month[tm->tm_mon],
224 infof(data, "%s\n", data->state.buffer);
227 static gnutls_datum_t load_file (const char *file)
230 gnutls_datum_t loaded_file = { NULL, 0 };
234 if(!(f = fopen(file, "r")))
236 if(fseek(f, 0, SEEK_END) != 0
237 || (filelen = ftell(f)) < 0
238 || fseek(f, 0, SEEK_SET) != 0
239 || !(ptr = malloc((size_t)filelen)))
241 if(fread(ptr, 1, (size_t)filelen, f) < (size_t)filelen) {
246 loaded_file.data = ptr;
247 loaded_file.size = (unsigned int)filelen;
253 static void unload_file(gnutls_datum_t data) {
258 /* this function does a SSL/TLS (re-)handshake */
259 static CURLcode handshake(struct connectdata *conn,
264 struct SessionHandle *data = conn->data;
265 struct ssl_connect_data *connssl = &conn->ssl[sockindex];
266 gnutls_session_t session = conn->ssl[sockindex].session;
267 curl_socket_t sockfd = conn->sock[sockindex];
273 /* check allowed time left */
274 timeout_ms = Curl_timeleft(data, NULL, duringconnect);
277 /* no need to continue if time already is up */
278 failf(data, "SSL connection timeout");
279 return CURLE_OPERATION_TIMEDOUT;
282 /* if ssl is expecting something, check if it's available. */
283 if(connssl->connecting_state == ssl_connect_2_reading
284 || connssl->connecting_state == ssl_connect_2_writing) {
286 curl_socket_t writefd = ssl_connect_2_writing==
287 connssl->connecting_state?sockfd:CURL_SOCKET_BAD;
288 curl_socket_t readfd = ssl_connect_2_reading==
289 connssl->connecting_state?sockfd:CURL_SOCKET_BAD;
291 what = Curl_socket_ready(readfd, writefd,
293 timeout_ms?timeout_ms:1000);
296 failf(data, "select/poll on SSL socket, errno: %d", SOCKERRNO);
297 return CURLE_SSL_CONNECT_ERROR;
302 else if(timeout_ms) {
304 failf(data, "SSL connection timeout at %ld", timeout_ms);
305 return CURLE_OPERATION_TIMEDOUT;
308 /* socket is readable or writable */
311 rc = gnutls_handshake(session);
313 if((rc == GNUTLS_E_AGAIN) || (rc == GNUTLS_E_INTERRUPTED)) {
314 connssl->connecting_state =
315 gnutls_record_get_direction(session)?
316 ssl_connect_2_writing:ssl_connect_2_reading;
319 else if((rc < 0) && !gnutls_error_is_fatal(rc)) {
320 const char *strerr = NULL;
322 if(rc == GNUTLS_E_WARNING_ALERT_RECEIVED) {
323 int alert = gnutls_alert_get(session);
324 strerr = gnutls_alert_get_name(alert);
328 strerr = gnutls_strerror(rc);
330 failf(data, "gnutls_handshake() warning: %s", strerr);
333 const char *strerr = NULL;
335 if(rc == GNUTLS_E_FATAL_ALERT_RECEIVED) {
336 int alert = gnutls_alert_get(session);
337 strerr = gnutls_alert_get_name(alert);
341 strerr = gnutls_strerror(rc);
343 failf(data, "gnutls_handshake() failed: %s", strerr);
344 return CURLE_SSL_CONNECT_ERROR;
347 /* Reset our connect state machine */
348 connssl->connecting_state = ssl_connect_1;
353 static gnutls_x509_crt_fmt_t do_file_type(const char *type)
355 if(!type || !type[0])
356 return GNUTLS_X509_FMT_PEM;
357 if(Curl_raw_equal(type, "PEM"))
358 return GNUTLS_X509_FMT_PEM;
359 if(Curl_raw_equal(type, "DER"))
360 return GNUTLS_X509_FMT_DER;
365 gtls_connect_step1(struct connectdata *conn,
368 struct SessionHandle *data = conn->data;
369 gnutls_session_t session;
373 bool sni = TRUE; /* default is SNI enabled */
375 struct in6_addr addr;
379 #ifndef USE_GNUTLS_PRIORITY_SET_DIRECT
380 static const int cipher_priority[] = {
381 /* These two ciphers were added to GnuTLS as late as ver. 3.0.1,
382 but this code path is only ever used for ver. < 2.12.0.
383 GNUTLS_CIPHER_AES_128_GCM,
384 GNUTLS_CIPHER_AES_256_GCM,
386 GNUTLS_CIPHER_AES_128_CBC,
387 GNUTLS_CIPHER_AES_256_CBC,
388 GNUTLS_CIPHER_CAMELLIA_128_CBC,
389 GNUTLS_CIPHER_CAMELLIA_256_CBC,
390 GNUTLS_CIPHER_3DES_CBC,
392 static const int cert_type_priority[] = { GNUTLS_CRT_X509, 0 };
393 static int protocol_priority[] = { 0, 0, 0, 0 };
395 #define GNUTLS_CIPHERS "NORMAL:-ARCFOUR-128:-CTYPE-ALL:+CTYPE-X509"
396 /* If GnuTLS was compiled without support for SRP it will error out if SRP is
397 requested in the priority string, so treat it specially
399 #define GNUTLS_SRP "+SRP"
400 const char* prioritylist;
401 const char *err = NULL;
404 int protocols_size = 2;
405 gnutls_datum_t protocols[2];
408 if(conn->ssl[sockindex].state == ssl_connection_complete)
409 /* to make us tolerant against being called more than once for the
416 /* GnuTLS only supports SSLv3 and TLSv1 */
417 if(data->set.ssl.version == CURL_SSLVERSION_SSLv2) {
418 failf(data, "GnuTLS does not support SSLv2");
419 return CURLE_SSL_CONNECT_ERROR;
421 else if(data->set.ssl.version == CURL_SSLVERSION_SSLv3)
422 sni = FALSE; /* SSLv3 has no SNI */
424 /* allocate a cred struct */
425 rc = gnutls_certificate_allocate_credentials(&conn->ssl[sockindex].cred);
426 if(rc != GNUTLS_E_SUCCESS) {
427 failf(data, "gnutls_cert_all_cred() failed: %s", gnutls_strerror(rc));
428 return CURLE_SSL_CONNECT_ERROR;
432 if(data->set.ssl.authtype == CURL_TLSAUTH_SRP) {
433 infof(data, "Using TLS-SRP username: %s\n", data->set.ssl.username);
435 rc = gnutls_srp_allocate_client_credentials(
436 &conn->ssl[sockindex].srp_client_cred);
437 if(rc != GNUTLS_E_SUCCESS) {
438 failf(data, "gnutls_srp_allocate_client_cred() failed: %s",
439 gnutls_strerror(rc));
440 return CURLE_OUT_OF_MEMORY;
443 rc = gnutls_srp_set_client_credentials(conn->ssl[sockindex].
445 data->set.ssl.username,
446 data->set.ssl.password);
447 if(rc != GNUTLS_E_SUCCESS) {
448 failf(data, "gnutls_srp_set_client_cred() failed: %s",
449 gnutls_strerror(rc));
450 return CURLE_BAD_FUNCTION_ARGUMENT;
455 if(data->set.ssl.CAfile) {
456 /* set the trusted CA cert bundle file */
457 gnutls_certificate_set_verify_flags(conn->ssl[sockindex].cred,
458 GNUTLS_VERIFY_ALLOW_X509_V1_CA_CRT);
460 rc = gnutls_certificate_set_x509_trust_file(conn->ssl[sockindex].cred,
461 data->set.ssl.CAfile,
462 GNUTLS_X509_FMT_PEM);
464 infof(data, "error reading ca cert file %s (%s)\n",
465 data->set.ssl.CAfile, gnutls_strerror(rc));
466 if(data->set.ssl.verifypeer)
467 return CURLE_SSL_CACERT_BADFILE;
470 infof(data, "found %d certificates in %s\n",
471 rc, data->set.ssl.CAfile);
474 if(data->set.ssl.CRLfile) {
475 /* set the CRL list file */
476 rc = gnutls_certificate_set_x509_crl_file(conn->ssl[sockindex].cred,
477 data->set.ssl.CRLfile,
478 GNUTLS_X509_FMT_PEM);
480 failf(data, "error reading crl file %s (%s)",
481 data->set.ssl.CRLfile, gnutls_strerror(rc));
482 return CURLE_SSL_CRL_BADFILE;
485 infof(data, "found %d CRL in %s\n",
486 rc, data->set.ssl.CRLfile);
489 /* Initialize TLS session as a client */
490 rc = gnutls_init(&conn->ssl[sockindex].session, GNUTLS_CLIENT);
491 if(rc != GNUTLS_E_SUCCESS) {
492 failf(data, "gnutls_init() failed: %d", rc);
493 return CURLE_SSL_CONNECT_ERROR;
496 /* convenient assign */
497 session = conn->ssl[sockindex].session;
499 if((0 == Curl_inet_pton(AF_INET, conn->host.name, &addr)) &&
501 (0 == Curl_inet_pton(AF_INET6, conn->host.name, &addr)) &&
504 (gnutls_server_name_set(session, GNUTLS_NAME_DNS, conn->host.name,
505 strlen(conn->host.name)) < 0))
506 infof(data, "WARNING: failed to configure server name indication (SNI) "
509 /* Use default priorities */
510 rc = gnutls_set_default_priority(session);
511 if(rc != GNUTLS_E_SUCCESS)
512 return CURLE_SSL_CONNECT_ERROR;
514 #ifndef USE_GNUTLS_PRIORITY_SET_DIRECT
515 rc = gnutls_cipher_set_priority(session, cipher_priority);
516 if(rc != GNUTLS_E_SUCCESS)
517 return CURLE_SSL_CONNECT_ERROR;
519 /* Sets the priority on the certificate types supported by gnutls. Priority
520 is higher for types specified before others. After specifying the types
521 you want, you must append a 0. */
522 rc = gnutls_certificate_type_set_priority(session, cert_type_priority);
523 if(rc != GNUTLS_E_SUCCESS)
524 return CURLE_SSL_CONNECT_ERROR;
526 if(data->set.ssl.cipher_list != NULL) {
527 failf(data, "can't pass a custom cipher list to older GnuTLS"
529 return CURLE_SSL_CONNECT_ERROR;
532 switch (data->set.ssl.version) {
533 case CURL_SSLVERSION_SSLv3:
534 protocol_priority[0] = GNUTLS_SSL3;
536 case CURL_SSLVERSION_DEFAULT:
537 case CURL_SSLVERSION_TLSv1:
538 protocol_priority[0] = GNUTLS_TLS1_0;
539 protocol_priority[1] = GNUTLS_TLS1_1;
540 protocol_priority[2] = GNUTLS_TLS1_2;
542 case CURL_SSLVERSION_TLSv1_0:
543 protocol_priority[0] = GNUTLS_TLS1_0;
545 case CURL_SSLVERSION_TLSv1_1:
546 protocol_priority[0] = GNUTLS_TLS1_1;
548 case CURL_SSLVERSION_TLSv1_2:
549 protocol_priority[0] = GNUTLS_TLS1_2;
551 case CURL_SSLVERSION_SSLv2:
553 failf(data, "GnuTLS does not support SSLv2");
554 return CURLE_SSL_CONNECT_ERROR;
557 rc = gnutls_protocol_set_priority(session, protocol_priority);
558 if(rc != GNUTLS_E_SUCCESS) {
559 failf(data, "Did you pass a valid GnuTLS cipher list?");
560 return CURLE_SSL_CONNECT_ERROR;
564 /* Ensure +SRP comes at the *end* of all relevant strings so that it can be
565 * removed if a run-time error indicates that SRP is not supported by this
567 switch (data->set.ssl.version) {
568 case CURL_SSLVERSION_SSLv3:
569 prioritylist = GNUTLS_CIPHERS ":-VERS-TLS-ALL:+VERS-SSL3.0";
572 case CURL_SSLVERSION_DEFAULT:
573 case CURL_SSLVERSION_TLSv1:
574 prioritylist = GNUTLS_CIPHERS ":-VERS-SSL3.0:" GNUTLS_SRP;
576 case CURL_SSLVERSION_TLSv1_0:
577 prioritylist = GNUTLS_CIPHERS ":-VERS-SSL3.0:-VERS-TLS-ALL:"
578 "+VERS-TLS1.0:" GNUTLS_SRP;
580 case CURL_SSLVERSION_TLSv1_1:
581 prioritylist = GNUTLS_CIPHERS ":-VERS-SSL3.0:-VERS-TLS-ALL:"
582 "+VERS-TLS1.1:" GNUTLS_SRP;
584 case CURL_SSLVERSION_TLSv1_2:
585 prioritylist = GNUTLS_CIPHERS ":-VERS-SSL3.0:-VERS-TLS-ALL:"
586 "+VERS-TLS1.2:" GNUTLS_SRP;
588 case CURL_SSLVERSION_SSLv2:
590 failf(data, "GnuTLS does not support SSLv2");
591 return CURLE_SSL_CONNECT_ERROR;
594 rc = gnutls_priority_set_direct(session, prioritylist, &err);
595 if((rc == GNUTLS_E_INVALID_REQUEST) && err) {
596 if(!strcmp(err, GNUTLS_SRP)) {
597 /* This GnuTLS was probably compiled without support for SRP.
598 * Note that fact and try again without it. */
599 int validprioritylen = curlx_uztosi(err - prioritylist);
600 char *prioritycopy = strdup(prioritylist);
602 return CURLE_OUT_OF_MEMORY;
604 infof(data, "This GnuTLS does not support SRP\n");
606 /* Remove the :+SRP */
607 prioritycopy[validprioritylen - 1] = 0;
608 rc = gnutls_priority_set_direct(session, prioritycopy, &err);
612 if(rc != GNUTLS_E_SUCCESS) {
613 failf(data, "Error %d setting GnuTLS cipher list starting with %s",
615 return CURLE_SSL_CONNECT_ERROR;
620 if(data->set.httpversion == CURL_HTTP_VERSION_2_0) {
621 if(data->set.ssl_enable_alpn) {
622 protocols[0].data = NGHTTP2_PROTO_VERSION_ID;
623 protocols[0].size = NGHTTP2_PROTO_VERSION_ID_LEN;
624 protocols[1].data = ALPN_HTTP_1_1;
625 protocols[1].size = ALPN_HTTP_1_1_LENGTH;
626 gnutls_alpn_set_protocols(session, protocols, protocols_size, 0);
627 infof(data, "ALPN, offering %s, %s\n", NGHTTP2_PROTO_VERSION_ID,
629 connssl->asked_for_h2 = TRUE;
632 infof(data, "SSL, can't negotiate HTTP/2.0 without ALPN\n");
637 if(data->set.str[STRING_CERT]) {
638 if(gnutls_certificate_set_x509_key_file(
639 conn->ssl[sockindex].cred,
640 data->set.str[STRING_CERT],
641 data->set.str[STRING_KEY] ?
642 data->set.str[STRING_KEY] : data->set.str[STRING_CERT],
643 do_file_type(data->set.str[STRING_CERT_TYPE]) ) !=
645 failf(data, "error reading X.509 key or certificate file");
646 return CURLE_SSL_CONNECT_ERROR;
651 /* put the credentials to the current session */
652 if(data->set.ssl.authtype == CURL_TLSAUTH_SRP) {
653 rc = gnutls_credentials_set(session, GNUTLS_CRD_SRP,
654 conn->ssl[sockindex].srp_client_cred);
655 if(rc != GNUTLS_E_SUCCESS)
656 failf(data, "gnutls_credentials_set() failed: %s", gnutls_strerror(rc));
660 rc = gnutls_credentials_set(session, GNUTLS_CRD_CERTIFICATE,
661 conn->ssl[sockindex].cred);
663 /* set the connection handle (file descriptor for the socket) */
664 gnutls_transport_set_ptr(session,
665 GNUTLS_INT_TO_POINTER_CAST(conn->sock[sockindex]));
667 /* register callback functions to send and receive data. */
668 gnutls_transport_set_push_function(session, Curl_gtls_push);
669 gnutls_transport_set_pull_function(session, Curl_gtls_pull);
671 /* lowat must be set to zero when using custom push and pull functions. */
672 gnutls_transport_set_lowat(session, 0);
675 if(data->set.ssl.verifystatus) {
676 rc = gnutls_ocsp_status_request_enable_client(session, NULL, 0, NULL);
677 if(rc != GNUTLS_E_SUCCESS) {
678 failf(data, "gnutls_ocsp_status_request_enable_client() failed: %d", rc);
679 return CURLE_SSL_CONNECT_ERROR;
684 /* This might be a reconnect, so we check for a session ID in the cache
685 to speed up things */
687 if(!Curl_ssl_getsessionid(conn, &ssl_sessionid, &ssl_idsize)) {
688 /* we got a session id, use it! */
689 gnutls_session_set_data(session, ssl_sessionid, ssl_idsize);
691 /* Informational message */
692 infof (data, "SSL re-using session ID\n");
698 static CURLcode pkp_pin_peer_pubkey(gnutls_x509_crt_t cert,
699 const char *pinnedpubkey)
702 size_t len1 = 0, len2 = 0;
703 unsigned char *buff1 = NULL;
705 gnutls_pubkey_t key = NULL;
707 /* Result is returned to caller */
709 CURLcode result = CURLE_SSL_PINNEDPUBKEYNOTMATCH;
711 /* if a path wasn't specified, don't pin */
712 if(NULL == pinnedpubkey)
719 /* Begin Gyrations to get the public key */
720 gnutls_pubkey_init(&key);
722 ret = gnutls_pubkey_import_x509(key, cert, 0);
726 ret = gnutls_pubkey_export(key, GNUTLS_X509_FMT_DER, NULL, &len1);
727 if(ret != GNUTLS_E_SHORT_MEMORY_BUFFER || len1 == 0)
730 buff1 = malloc(len1);
736 ret = gnutls_pubkey_export(key, GNUTLS_X509_FMT_DER, buff1, &len2);
737 if(ret < 0 || len1 != len2)
742 /* The one good exit point */
743 result = Curl_pin_peer_pubkey(pinnedpubkey, buff1, len1);
747 gnutls_pubkey_deinit(key);
749 Curl_safefree(buff1);
754 static Curl_recv gtls_recv;
755 static Curl_send gtls_send;
758 gtls_connect_step3(struct connectdata *conn,
761 unsigned int cert_list_size;
762 const gnutls_datum_t *chainp;
763 unsigned int verify_status;
764 gnutls_x509_crt_t x509_cert,x509_issuer;
765 gnutls_datum_t issuerp;
766 char certbuf[256] = ""; /* big enough? */
772 struct SessionHandle *data = conn->data;
773 gnutls_session_t session = conn->ssl[sockindex].session;
778 gnutls_datum_t proto;
780 CURLcode result = CURLE_OK;
782 /* This function will return the peer's raw certificate (chain) as sent by
783 the peer. These certificates are in raw format (DER encoded for
784 X.509). In case of a X.509 then a certificate list may be present. The
785 first certificate in the list is the peer's certificate, following the
786 issuer's certificate, then the issuer's issuer etc. */
788 chainp = gnutls_certificate_get_peers(session, &cert_list_size);
790 if(data->set.ssl.verifypeer ||
791 data->set.ssl.verifyhost ||
792 data->set.ssl.issuercert) {
794 if(data->set.ssl.authtype == CURL_TLSAUTH_SRP
795 && data->set.ssl.username != NULL
796 && !data->set.ssl.verifypeer
797 && gnutls_cipher_get(session)) {
798 /* no peer cert, but auth is ok if we have SRP user and cipher and no
803 failf(data, "failed to get server cert");
804 return CURLE_PEER_FAILED_VERIFICATION;
809 infof(data, "\t common name: WARNING couldn't obtain\n");
812 if(data->set.ssl.verifypeer) {
813 /* This function will try to verify the peer's certificate and return its
814 status (trusted, invalid etc.). The value of status should be one or
815 more of the gnutls_certificate_status_t enumerated elements bitwise
816 or'd. To avoid denial of service attacks some default upper limits
817 regarding the certificate key size and chain size are set. To override
818 them use gnutls_certificate_set_verify_limits(). */
820 rc = gnutls_certificate_verify_peers2(session, &verify_status);
822 failf(data, "server cert verify failed: %d", rc);
823 return CURLE_SSL_CONNECT_ERROR;
826 /* verify_status is a bitmask of gnutls_certificate_status bits */
827 if(verify_status & GNUTLS_CERT_INVALID) {
828 if(data->set.ssl.verifypeer) {
829 failf(data, "server certificate verification failed. CAfile: %s "
830 "CRLfile: %s", data->set.ssl.CAfile?data->set.ssl.CAfile:"none",
831 data->set.ssl.CRLfile?data->set.ssl.CRLfile:"none");
832 return CURLE_SSL_CACERT;
835 infof(data, "\t server certificate verification FAILED\n");
838 infof(data, "\t server certificate verification OK\n");
841 infof(data, "\t server certificate verification SKIPPED\n");
844 if(data->set.ssl.verifystatus) {
845 if(gnutls_ocsp_status_request_is_checked(session, 0) == 0) {
846 if(verify_status & GNUTLS_CERT_REVOKED)
847 failf(data, "SSL server certificate was REVOKED\n");
849 failf(data, "SSL server certificate status verification FAILED");
851 return CURLE_SSL_INVALIDCERTSTATUS;
854 infof(data, "SSL server certificate status verification OK\n");
857 infof(data, "SSL server certificate status verification SKIPPED\n");
860 /* initialize an X.509 certificate structure. */
861 gnutls_x509_crt_init(&x509_cert);
864 /* convert the given DER or PEM encoded Certificate to the native
865 gnutls_x509_crt_t format */
866 gnutls_x509_crt_import(x509_cert, chainp, GNUTLS_X509_FMT_DER);
868 if(data->set.ssl.issuercert) {
869 gnutls_x509_crt_init(&x509_issuer);
870 issuerp = load_file(data->set.ssl.issuercert);
871 gnutls_x509_crt_import(x509_issuer, &issuerp, GNUTLS_X509_FMT_PEM);
872 rc = gnutls_x509_crt_check_issuer(x509_cert,x509_issuer);
873 gnutls_x509_crt_deinit(x509_issuer);
874 unload_file(issuerp);
876 failf(data, "server certificate issuer check failed (IssuerCert: %s)",
877 data->set.ssl.issuercert?data->set.ssl.issuercert:"none");
878 gnutls_x509_crt_deinit(x509_cert);
879 return CURLE_SSL_ISSUER_ERROR;
881 infof(data,"\t server certificate issuer check OK (Issuer Cert: %s)\n",
882 data->set.ssl.issuercert?data->set.ssl.issuercert:"none");
885 size=sizeof(certbuf);
886 rc = gnutls_x509_crt_get_dn_by_oid(x509_cert, GNUTLS_OID_X520_COMMON_NAME,
887 0, /* the first and only one */
892 infof(data, "error fetching CN from cert:%s\n",
893 gnutls_strerror(rc));
896 /* This function will check if the given certificate's subject matches the
897 given hostname. This is a basic implementation of the matching described
898 in RFC2818 (HTTPS), which takes into account wildcards, and the subject
899 alternative name PKIX extension. Returns non zero on success, and zero on
901 rc = gnutls_x509_crt_check_hostname(x509_cert, conn->host.name);
902 #if GNUTLS_VERSION_NUMBER < 0x030306
903 /* Before 3.3.6, gnutls_x509_crt_check_hostname() didn't check IP
907 #define use_addr in6_addr
909 #define use_addr in_addr
911 unsigned char addrbuf[sizeof(struct use_addr)];
912 unsigned char certaddr[sizeof(struct use_addr)];
913 size_t addrlen = 0, certaddrlen;
917 if(Curl_inet_pton(AF_INET, conn->host.name, addrbuf) > 0)
920 else if(Curl_inet_pton(AF_INET6, conn->host.name, addrbuf) > 0)
926 certaddrlen = sizeof(certaddr);
927 ret = gnutls_x509_crt_get_subject_alt_name(x509_cert, i, certaddr,
929 /* If this happens, it wasn't an IP address. */
930 if(ret == GNUTLS_E_SHORT_MEMORY_BUFFER)
934 if(ret != GNUTLS_SAN_IPADDRESS)
936 if(certaddrlen == addrlen && !memcmp(addrbuf, certaddr, addrlen)) {
945 if(data->set.ssl.verifyhost) {
946 failf(data, "SSL: certificate subject name (%s) does not match "
947 "target host name '%s'", certbuf, conn->host.dispname);
948 gnutls_x509_crt_deinit(x509_cert);
949 return CURLE_PEER_FAILED_VERIFICATION;
952 infof(data, "\t common name: %s (does not match '%s')\n",
953 certbuf, conn->host.dispname);
956 infof(data, "\t common name: %s (matched)\n", certbuf);
958 /* Check for time-based validity */
959 certclock = gnutls_x509_crt_get_expiration_time(x509_cert);
961 if(certclock == (time_t)-1) {
962 if(data->set.ssl.verifypeer) {
963 failf(data, "server cert expiration date verify failed");
964 gnutls_x509_crt_deinit(x509_cert);
965 return CURLE_SSL_CONNECT_ERROR;
968 infof(data, "\t server certificate expiration date verify FAILED\n");
971 if(certclock < time(NULL)) {
972 if(data->set.ssl.verifypeer) {
973 failf(data, "server certificate expiration date has passed.");
974 gnutls_x509_crt_deinit(x509_cert);
975 return CURLE_PEER_FAILED_VERIFICATION;
978 infof(data, "\t server certificate expiration date FAILED\n");
981 infof(data, "\t server certificate expiration date OK\n");
984 certclock = gnutls_x509_crt_get_activation_time(x509_cert);
986 if(certclock == (time_t)-1) {
987 if(data->set.ssl.verifypeer) {
988 failf(data, "server cert activation date verify failed");
989 gnutls_x509_crt_deinit(x509_cert);
990 return CURLE_SSL_CONNECT_ERROR;
993 infof(data, "\t server certificate activation date verify FAILED\n");
996 if(certclock > time(NULL)) {
997 if(data->set.ssl.verifypeer) {
998 failf(data, "server certificate not activated yet.");
999 gnutls_x509_crt_deinit(x509_cert);
1000 return CURLE_PEER_FAILED_VERIFICATION;
1003 infof(data, "\t server certificate activation date FAILED\n");
1006 infof(data, "\t server certificate activation date OK\n");
1009 ptr = data->set.str[STRING_SSL_PINNEDPUBLICKEY];
1011 result = pkp_pin_peer_pubkey(x509_cert, ptr);
1012 if(result != CURLE_OK) {
1013 failf(data, "SSL: public key does not match pinned public key!");
1014 gnutls_x509_crt_deinit(x509_cert);
1030 /* public key algorithm's parameters */
1031 algo = gnutls_x509_crt_get_pk_algorithm(x509_cert, &bits);
1032 infof(data, "\t certificate public key: %s\n",
1033 gnutls_pk_algorithm_get_name(algo));
1035 /* version of the X.509 certificate. */
1036 infof(data, "\t certificate version: #%d\n",
1037 gnutls_x509_crt_get_version(x509_cert));
1040 size = sizeof(certbuf);
1041 gnutls_x509_crt_get_dn(x509_cert, certbuf, &size);
1042 infof(data, "\t subject: %s\n", certbuf);
1044 certclock = gnutls_x509_crt_get_activation_time(x509_cert);
1045 showtime(data, "start date", certclock);
1047 certclock = gnutls_x509_crt_get_expiration_time(x509_cert);
1048 showtime(data, "expire date", certclock);
1050 size = sizeof(certbuf);
1051 gnutls_x509_crt_get_issuer_dn(x509_cert, certbuf, &size);
1052 infof(data, "\t issuer: %s\n", certbuf);
1054 gnutls_x509_crt_deinit(x509_cert);
1056 /* compression algorithm (if any) */
1057 ptr = gnutls_compression_get_name(gnutls_compression_get(session));
1058 /* the *_get_name() says "NULL" if GNUTLS_COMP_NULL is returned */
1059 infof(data, "\t compression: %s\n", ptr);
1061 /* the name of the cipher used. ie 3DES. */
1062 ptr = gnutls_cipher_get_name(gnutls_cipher_get(session));
1063 infof(data, "\t cipher: %s\n", ptr);
1065 /* the MAC algorithms name. ie SHA1 */
1066 ptr = gnutls_mac_get_name(gnutls_mac_get(session));
1067 infof(data, "\t MAC: %s\n", ptr);
1070 if(data->set.ssl_enable_alpn) {
1071 rc = gnutls_alpn_get_selected_protocol(session, &proto);
1073 infof(data, "ALPN, server accepted to use %.*s\n", proto.size,
1076 if(proto.size == NGHTTP2_PROTO_VERSION_ID_LEN &&
1077 memcmp(NGHTTP2_PROTO_VERSION_ID, proto.data,
1078 NGHTTP2_PROTO_VERSION_ID_LEN) == 0) {
1079 conn->negnpn = NPN_HTTP2;
1081 else if(proto.size == ALPN_HTTP_1_1_LENGTH && memcmp(ALPN_HTTP_1_1,
1082 proto.data, ALPN_HTTP_1_1_LENGTH) == 0) {
1083 conn->negnpn = NPN_HTTP1_1;
1086 else if(connssl->asked_for_h2) {
1087 infof(data, "ALPN, server did not agree to a protocol\n");
1092 conn->ssl[sockindex].state = ssl_connection_complete;
1093 conn->recv[sockindex] = gtls_recv;
1094 conn->send[sockindex] = gtls_send;
1097 /* we always unconditionally get the session id here, as even if we
1098 already got it from the cache and asked to use it in the connection, it
1099 might've been rejected and then a new one is in use now and we need to
1101 void *connect_sessionid;
1102 size_t connect_idsize = 0;
1104 /* get the session ID data size */
1105 gnutls_session_get_data(session, NULL, &connect_idsize);
1106 connect_sessionid = malloc(connect_idsize); /* get a buffer for it */
1108 if(connect_sessionid) {
1109 /* extract session ID to the allocated buffer */
1110 gnutls_session_get_data(session, connect_sessionid, &connect_idsize);
1112 incache = !(Curl_ssl_getsessionid(conn, &ssl_sessionid, NULL));
1114 /* there was one before in the cache, so instead of risking that the
1115 previous one was rejected, we just kill that and store the new */
1116 Curl_ssl_delsessionid(conn, ssl_sessionid);
1119 /* store this session id */
1120 result = Curl_ssl_addsessionid(conn, connect_sessionid, connect_idsize);
1122 free(connect_sessionid);
1123 result = CURLE_OUT_OF_MEMORY;
1127 result = CURLE_OUT_OF_MEMORY;
1135 * This function is called after the TCP connect has completed. Setup the TLS
1136 * layer and do all necessary magic.
1138 /* We use connssl->connecting_state to keep track of the connection status;
1139 there are three states: 'ssl_connect_1' (not started yet or complete),
1140 'ssl_connect_2_reading' (waiting for data from server), and
1141 'ssl_connect_2_writing' (waiting to be able to write).
1144 gtls_connect_common(struct connectdata *conn,
1150 struct ssl_connect_data *connssl = &conn->ssl[sockindex];
1152 /* Initiate the connection, if not already done */
1153 if(ssl_connect_1==connssl->connecting_state) {
1154 rc = gtls_connect_step1 (conn, sockindex);
1159 rc = handshake(conn, sockindex, TRUE, nonblocking);
1161 /* handshake() sets its own error message with failf() */
1164 /* Finish connecting once the handshake is done */
1165 if(ssl_connect_1==connssl->connecting_state) {
1166 rc = gtls_connect_step3(conn, sockindex);
1171 *done = ssl_connect_1==connssl->connecting_state;
1177 Curl_gtls_connect_nonblocking(struct connectdata *conn,
1181 return gtls_connect_common(conn, sockindex, TRUE, done);
1185 Curl_gtls_connect(struct connectdata *conn,
1192 result = gtls_connect_common(conn, sockindex, FALSE, &done);
1201 static ssize_t gtls_send(struct connectdata *conn,
1207 ssize_t rc = gnutls_record_send(conn->ssl[sockindex].session, mem, len);
1210 *curlcode = (rc == GNUTLS_E_AGAIN)
1220 void Curl_gtls_close_all(struct SessionHandle *data)
1222 /* FIX: make the OpenSSL code more generic and use parts of it here */
1226 static void close_one(struct connectdata *conn,
1229 if(conn->ssl[idx].session) {
1230 gnutls_bye(conn->ssl[idx].session, GNUTLS_SHUT_RDWR);
1231 gnutls_deinit(conn->ssl[idx].session);
1232 conn->ssl[idx].session = NULL;
1234 if(conn->ssl[idx].cred) {
1235 gnutls_certificate_free_credentials(conn->ssl[idx].cred);
1236 conn->ssl[idx].cred = NULL;
1239 if(conn->ssl[idx].srp_client_cred) {
1240 gnutls_srp_free_client_credentials(conn->ssl[idx].srp_client_cred);
1241 conn->ssl[idx].srp_client_cred = NULL;
1246 void Curl_gtls_close(struct connectdata *conn, int sockindex)
1248 close_one(conn, sockindex);
1252 * This function is called to shut down the SSL layer but keep the
1253 * socket open (CCC - Clear Command Channel)
1255 int Curl_gtls_shutdown(struct connectdata *conn, int sockindex)
1259 struct SessionHandle *data = conn->data;
1263 /* This has only been tested on the proftpd server, and the mod_tls code
1264 sends a close notify alert without waiting for a close notify alert in
1265 response. Thus we wait for a close notify alert from the server, but
1266 we do not send one. Let's hope other servers do the same... */
1268 if(data->set.ftp_ccc == CURLFTPSSL_CCC_ACTIVE)
1269 gnutls_bye(conn->ssl[sockindex].session, GNUTLS_SHUT_WR);
1271 if(conn->ssl[sockindex].session) {
1273 int what = Curl_socket_ready(conn->sock[sockindex],
1274 CURL_SOCKET_BAD, SSL_SHUTDOWN_TIMEOUT);
1276 /* Something to read, let's do it and hope that it is the close
1277 notify alert from the server */
1278 result = gnutls_record_recv(conn->ssl[sockindex].session,
1282 /* This is the expected response. There was no data but only
1283 the close notify alert */
1286 case GNUTLS_E_AGAIN:
1287 case GNUTLS_E_INTERRUPTED:
1288 infof(data, "GNUTLS_E_AGAIN || GNUTLS_E_INTERRUPTED\n");
1296 else if(0 == what) {
1298 failf(data, "SSL shutdown timeout");
1303 /* anything that gets here is fatally bad */
1304 failf(data, "select/poll on SSL socket, errno: %d", SOCKERRNO);
1309 gnutls_deinit(conn->ssl[sockindex].session);
1311 gnutls_certificate_free_credentials(conn->ssl[sockindex].cred);
1314 if(data->set.ssl.authtype == CURL_TLSAUTH_SRP
1315 && data->set.ssl.username != NULL)
1316 gnutls_srp_free_client_credentials(conn->ssl[sockindex].srp_client_cred);
1319 conn->ssl[sockindex].cred = NULL;
1320 conn->ssl[sockindex].session = NULL;
1325 static ssize_t gtls_recv(struct connectdata *conn, /* connection data */
1326 int num, /* socketindex */
1327 char *buf, /* store read data here */
1328 size_t buffersize, /* max amount to read */
1333 ret = gnutls_record_recv(conn->ssl[num].session, buf, buffersize);
1334 if((ret == GNUTLS_E_AGAIN) || (ret == GNUTLS_E_INTERRUPTED)) {
1335 *curlcode = CURLE_AGAIN;
1339 if(ret == GNUTLS_E_REHANDSHAKE) {
1340 /* BLOCKING call, this is bad but a work-around for now. Fixing this "the
1341 proper way" takes a whole lot of work. */
1342 CURLcode result = handshake(conn, num, FALSE, FALSE);
1344 /* handshake() writes error message on its own */
1347 *curlcode = CURLE_AGAIN; /* then return as if this was a wouldblock */
1352 failf(conn->data, "GnuTLS recv error (%d): %s",
1353 (int)ret, gnutls_strerror((int)ret));
1354 *curlcode = CURLE_RECV_ERROR;
1361 void Curl_gtls_session_free(void *ptr)
1366 size_t Curl_gtls_version(char *buffer, size_t size)
1368 return snprintf(buffer, size, "GnuTLS/%s", gnutls_check_version(NULL));
1371 #ifndef USE_GNUTLS_NETTLE
1372 static int Curl_gtls_seed(struct SessionHandle *data)
1374 /* we have the "SSL is seeded" boolean static to prevent multiple
1375 time-consuming seedings in vain */
1376 static bool ssl_seeded = FALSE;
1378 /* Quickly add a bit of entropy */
1379 gcry_fast_random_poll();
1381 if(!ssl_seeded || data->set.str[STRING_SSL_RANDOM_FILE] ||
1382 data->set.str[STRING_SSL_EGDSOCKET]) {
1384 /* TODO: to a good job seeding the RNG
1385 This may involve the gcry_control function and these options:
1386 GCRYCTL_SET_RANDOM_SEED_FILE
1387 GCRYCTL_SET_RNDEGD_SOCKET
1395 /* data might be NULL! */
1396 int Curl_gtls_random(struct SessionHandle *data,
1397 unsigned char *entropy,
1400 #if defined(USE_GNUTLS_NETTLE)
1402 gnutls_rnd(GNUTLS_RND_RANDOM, entropy, length);
1403 #elif defined(USE_GNUTLS)
1405 Curl_gtls_seed(data); /* Initiate the seed if not already done */
1406 gcry_randomize(entropy, length, GCRY_STRONG_RANDOM);
1411 void Curl_gtls_md5sum(unsigned char *tmp, /* input */
1413 unsigned char *md5sum, /* output */
1416 #if defined(USE_GNUTLS_NETTLE)
1417 struct md5_ctx MD5pw;
1419 md5_update(&MD5pw, (unsigned int)tmplen, tmp);
1420 md5_digest(&MD5pw, (unsigned int)md5len, md5sum);
1421 #elif defined(USE_GNUTLS)
1423 gcry_md_open(&MD5pw, GCRY_MD_MD5, 0);
1424 gcry_md_write(MD5pw, tmp, tmplen);
1425 memcpy(md5sum, gcry_md_read (MD5pw, 0), md5len);
1426 gcry_md_close(MD5pw);
1430 bool Curl_gtls_cert_status_request(void)
1439 #endif /* USE_GNUTLS */