2 * Copyright 1995-2016 The OpenSSL Project Authors. All Rights Reserved.
4 * Licensed under the OpenSSL license (the "License"). You may not use
5 * this file except in compliance with the License. You can obtain a copy
6 * in the file LICENSE in the source distribution or at
7 * https://www.openssl.org/source/license.html
10 /* ====================================================================
11 * Copyright 2002 Sun Microsystems, Inc. ALL RIGHTS RESERVED.
12 * ECC cipher suite support in OpenSSL originally developed by
13 * SUN MICROSYSTEMS, INC., and contributed to the OpenSSL project.
19 #include "../ssl_locl.h"
20 #include "statem_locl.h"
21 #include <openssl/buffer.h>
22 #include <openssl/objects.h>
23 #include <openssl/evp.h>
24 #include <openssl/x509.h>
27 * send s->init_buf in records of type 'type' (SSL3_RT_HANDSHAKE or
28 * SSL3_RT_CHANGE_CIPHER_SPEC)
30 int ssl3_do_write(SSL *s, int type)
35 ret = ssl3_write_bytes(s, type, &s->init_buf->data[s->init_off],
36 s->init_num, &written);
39 if (type == SSL3_RT_HANDSHAKE)
41 * should not be done for 'Hello Request's, but in that case we'll
42 * ignore the result anyway
44 if (!ssl3_finish_mac(s,
45 (unsigned char *)&s->init_buf->data[s->init_off],
49 if (written == s->init_num) {
51 s->msg_callback(1, s->version, type, s->init_buf->data,
52 (size_t)(s->init_off + s->init_num), s,
56 s->init_off += written;
57 s->init_num -= written;
61 int tls_close_construct_packet(SSL *s, WPACKET *pkt, int htype)
65 if ((htype != SSL3_MT_CHANGE_CIPHER_SPEC && !WPACKET_close(pkt))
66 || !WPACKET_get_length(pkt, &msglen)
69 s->init_num = (int)msglen;
75 int tls_construct_finished(SSL *s, WPACKET *pkt)
82 sender = s->method->ssl3_enc->server_finished_label;
83 slen = s->method->ssl3_enc->server_finished_label_len;
85 sender = s->method->ssl3_enc->client_finished_label;
86 slen = s->method->ssl3_enc->client_finished_label_len;
89 finish_md_len = s->method->ssl3_enc->final_finish_mac(s,
91 s->s3->tmp.finish_md);
92 if (finish_md_len == 0) {
93 SSLerr(SSL_F_TLS_CONSTRUCT_FINISHED, ERR_R_INTERNAL_ERROR);
97 s->s3->tmp.finish_md_len = finish_md_len;
99 if (!WPACKET_memcpy(pkt, s->s3->tmp.finish_md, finish_md_len)) {
100 SSLerr(SSL_F_TLS_CONSTRUCT_FINISHED, ERR_R_INTERNAL_ERROR);
105 * Copy the finished so we can use it for renegotiation checks
108 OPENSSL_assert(finish_md_len <= EVP_MAX_MD_SIZE);
109 memcpy(s->s3->previous_client_finished, s->s3->tmp.finish_md,
111 s->s3->previous_client_finished_len = finish_md_len;
113 OPENSSL_assert(finish_md_len <= EVP_MAX_MD_SIZE);
114 memcpy(s->s3->previous_server_finished, s->s3->tmp.finish_md,
116 s->s3->previous_server_finished_len = finish_md_len;
121 ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR);
125 #ifndef OPENSSL_NO_NEXTPROTONEG
127 * ssl3_take_mac calculates the Finished MAC for the handshakes messages seen
130 static void ssl3_take_mac(SSL *s)
135 * If no new cipher setup return immediately: other functions will set
136 * the appropriate error.
138 if (s->s3->tmp.new_cipher == NULL)
141 sender = s->method->ssl3_enc->server_finished_label;
142 slen = s->method->ssl3_enc->server_finished_label_len;
144 sender = s->method->ssl3_enc->client_finished_label;
145 slen = s->method->ssl3_enc->client_finished_label_len;
148 s->s3->tmp.peer_finish_md_len = s->method->ssl3_enc->final_finish_mac(s,
151 s->s3->tmp.peer_finish_md);
156 * Comparison function used in a call to qsort (see tls_collect_extensions()
158 * The two arguments |p1| and |p2| are expected to be pointers to RAW_EXTENSIONs
161 * 1 if the type for p1 is greater than p2
162 * 0 if the type for p1 and p2 are the same
163 * -1 if the type for p1 is less than p2
165 static int compare_extensions(const void *p1, const void *p2)
167 const RAW_EXTENSION *e1 = (const RAW_EXTENSION *)p1;
168 const RAW_EXTENSION *e2 = (const RAW_EXTENSION *)p2;
170 if (e1->type < e2->type)
172 else if (e1->type > e2->type)
179 * Gather a list of all the extensions. We don't actually process the content
180 * of the extensions yet, except to check their types.
182 * Per http://tools.ietf.org/html/rfc5246#section-7.4.1.4, there may not be
183 * more than one extension of the same type in a ClientHello or ServerHello.
184 * This function returns 1 if all extensions are unique and we have parsed their
185 * types, and 0 if the extensions contain duplicates, could not be successfully
186 * parsed, or an internal error occurred.
189 * TODO(TLS1.3): Refactor ServerHello extension parsing to use this and then
190 * remove tls1_check_duplicate_extensions()
192 int tls_collect_extensions(PACKET *packet, RAW_EXTENSION **res,
193 size_t *numfound, int *ad)
195 PACKET extensions = *packet;
196 size_t num_extensions = 0, i = 0;
197 RAW_EXTENSION *raw_extensions = NULL;
199 /* First pass: count the extensions. */
200 while (PACKET_remaining(&extensions) > 0) {
204 if (!PACKET_get_net_2(&extensions, &type) ||
205 !PACKET_get_length_prefixed_2(&extensions, &extension)) {
206 *ad = SSL_AD_DECODE_ERROR;
212 if (num_extensions > 0) {
213 raw_extensions = OPENSSL_malloc(sizeof(*raw_extensions)
215 if (raw_extensions == NULL) {
216 *ad = SSL_AD_INTERNAL_ERROR;
217 SSLerr(SSL_F_TLS_COLLECT_EXTENSIONS, ERR_R_MALLOC_FAILURE);
221 /* Second pass: collect the extensions. */
222 for (i = 0; i < num_extensions; i++) {
223 if (!PACKET_get_net_2(packet, &raw_extensions[i].type) ||
224 !PACKET_get_length_prefixed_2(packet,
225 &raw_extensions[i].data)) {
226 /* This should not happen. */
227 *ad = SSL_AD_INTERNAL_ERROR;
228 SSLerr(SSL_F_TLS_COLLECT_EXTENSIONS, ERR_R_INTERNAL_ERROR);
233 if (PACKET_remaining(packet) != 0) {
234 *ad = SSL_AD_DECODE_ERROR;
235 SSLerr(SSL_F_TLS_COLLECT_EXTENSIONS, SSL_R_LENGTH_MISMATCH);
238 /* Sort the extensions and make sure there are no duplicates. */
239 qsort(raw_extensions, num_extensions, sizeof(*raw_extensions),
241 for (i = 1; i < num_extensions; i++) {
242 if (raw_extensions[i - 1].type == raw_extensions[i].type) {
243 *ad = SSL_AD_DECODE_ERROR;
249 *res = raw_extensions;
250 *numfound = num_extensions;
254 OPENSSL_free(raw_extensions);
260 MSG_PROCESS_RETURN tls_process_change_cipher_spec(SSL *s, PACKET *pkt)
265 remain = PACKET_remaining(pkt);
267 * 'Change Cipher Spec' is just a single byte, which should already have
268 * been consumed by ssl_get_message() so there should be no bytes left,
269 * unless we're using DTLS1_BAD_VER, which has an extra 2 bytes
271 if (SSL_IS_DTLS(s)) {
272 if ((s->version == DTLS1_BAD_VER
273 && remain != DTLS1_CCS_HEADER_LENGTH + 1)
274 || (s->version != DTLS1_BAD_VER
275 && remain != DTLS1_CCS_HEADER_LENGTH - 1)) {
276 al = SSL_AD_ILLEGAL_PARAMETER;
277 SSLerr(SSL_F_TLS_PROCESS_CHANGE_CIPHER_SPEC,
278 SSL_R_BAD_CHANGE_CIPHER_SPEC);
283 al = SSL_AD_ILLEGAL_PARAMETER;
284 SSLerr(SSL_F_TLS_PROCESS_CHANGE_CIPHER_SPEC,
285 SSL_R_BAD_CHANGE_CIPHER_SPEC);
290 /* Check we have a cipher to change to */
291 if (s->s3->tmp.new_cipher == NULL) {
292 al = SSL_AD_UNEXPECTED_MESSAGE;
293 SSLerr(SSL_F_TLS_PROCESS_CHANGE_CIPHER_SPEC, SSL_R_CCS_RECEIVED_EARLY);
297 s->s3->change_cipher_spec = 1;
298 if (!ssl3_do_change_cipher_spec(s)) {
299 al = SSL_AD_INTERNAL_ERROR;
300 SSLerr(SSL_F_TLS_PROCESS_CHANGE_CIPHER_SPEC, ERR_R_INTERNAL_ERROR);
304 if (SSL_IS_DTLS(s)) {
305 dtls1_reset_seq_numbers(s, SSL3_CC_READ);
307 if (s->version == DTLS1_BAD_VER)
308 s->d1->handshake_read_seq++;
310 #ifndef OPENSSL_NO_SCTP
312 * Remember that a CCS has been received, so that an old key of
313 * SCTP-Auth can be deleted when a CCS is sent. Will be ignored if no
316 BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_AUTH_CCS_RCVD, 1, NULL);
320 return MSG_PROCESS_CONTINUE_READING;
322 ssl3_send_alert(s, SSL3_AL_FATAL, al);
323 ossl_statem_set_error(s);
324 return MSG_PROCESS_ERROR;
327 MSG_PROCESS_RETURN tls_process_finished(SSL *s, PACKET *pkt)
332 /* If this occurs, we have missed a message */
333 if (!s->s3->change_cipher_spec) {
334 al = SSL_AD_UNEXPECTED_MESSAGE;
335 SSLerr(SSL_F_TLS_PROCESS_FINISHED, SSL_R_GOT_A_FIN_BEFORE_A_CCS);
338 s->s3->change_cipher_spec = 0;
340 md_len = s->s3->tmp.peer_finish_md_len;
342 if (md_len != PACKET_remaining(pkt)) {
343 al = SSL_AD_DECODE_ERROR;
344 SSLerr(SSL_F_TLS_PROCESS_FINISHED, SSL_R_BAD_DIGEST_LENGTH);
348 if (CRYPTO_memcmp(PACKET_data(pkt), s->s3->tmp.peer_finish_md,
350 al = SSL_AD_DECRYPT_ERROR;
351 SSLerr(SSL_F_TLS_PROCESS_FINISHED, SSL_R_DIGEST_CHECK_FAILED);
356 * Copy the finished so we can use it for renegotiation checks
359 OPENSSL_assert(md_len <= EVP_MAX_MD_SIZE);
360 memcpy(s->s3->previous_client_finished, s->s3->tmp.peer_finish_md,
362 s->s3->previous_client_finished_len = md_len;
364 OPENSSL_assert(md_len <= EVP_MAX_MD_SIZE);
365 memcpy(s->s3->previous_server_finished, s->s3->tmp.peer_finish_md,
367 s->s3->previous_server_finished_len = md_len;
370 return MSG_PROCESS_FINISHED_READING;
372 ssl3_send_alert(s, SSL3_AL_FATAL, al);
373 ossl_statem_set_error(s);
374 return MSG_PROCESS_ERROR;
377 int tls_construct_change_cipher_spec(SSL *s, WPACKET *pkt)
379 if (!WPACKET_put_bytes_u8(pkt, SSL3_MT_CCS)) {
380 SSLerr(SSL_F_TLS_CONSTRUCT_CHANGE_CIPHER_SPEC, ERR_R_INTERNAL_ERROR);
381 ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR);
388 unsigned long ssl3_output_cert_chain(SSL *s, WPACKET *pkt, CERT_PKEY *cpk)
390 if (!WPACKET_start_sub_packet_u24(pkt)
391 || !ssl_add_cert_chain(s, pkt, cpk)
392 || !WPACKET_close(pkt)) {
393 SSLerr(SSL_F_SSL3_OUTPUT_CERT_CHAIN, ERR_R_INTERNAL_ERROR);
399 WORK_STATE tls_finish_handshake(SSL *s, WORK_STATE wst)
401 void (*cb) (const SSL *ssl, int type, int val) = NULL;
403 #ifndef OPENSSL_NO_SCTP
404 if (SSL_IS_DTLS(s) && BIO_dgram_is_sctp(SSL_get_wbio(s))) {
406 ret = dtls_wait_for_dry(s);
407 if (ret != WORK_FINISHED_CONTINUE)
412 /* clean a few things up */
413 ssl3_cleanup_key_block(s);
415 if (!SSL_IS_DTLS(s)) {
417 * We don't do this in DTLS because we may still need the init_buf
418 * in case there are any unexpected retransmits
420 BUF_MEM_free(s->init_buf);
424 ssl_free_wbio_buffer(s);
428 if (!s->server || s->renegotiate == 2) {
429 /* skipped if we just sent a HelloRequest */
434 ssl_update_cache(s, SSL_SESS_CACHE_SERVER);
436 s->ctx->stats.sess_accept_good++;
437 s->handshake_func = ossl_statem_accept;
439 ssl_update_cache(s, SSL_SESS_CACHE_CLIENT);
441 s->ctx->stats.sess_hit++;
443 s->handshake_func = ossl_statem_connect;
444 s->ctx->stats.sess_connect_good++;
447 if (s->info_callback != NULL)
448 cb = s->info_callback;
449 else if (s->ctx->info_callback != NULL)
450 cb = s->ctx->info_callback;
453 cb(s, SSL_CB_HANDSHAKE_DONE, 1);
455 if (SSL_IS_DTLS(s)) {
456 /* done with handshaking */
457 s->d1->handshake_read_seq = 0;
458 s->d1->handshake_write_seq = 0;
459 s->d1->next_handshake_write_seq = 0;
460 dtls1_clear_received_buffer(s);
464 return WORK_FINISHED_STOP;
467 int tls_get_message_header(SSL *s, int *mt)
469 /* s->init_num < SSL3_HM_HEADER_LENGTH */
470 int skip_message, i, recvd_type, al;
474 p = (unsigned char *)s->init_buf->data;
477 while (s->init_num < SSL3_HM_HEADER_LENGTH) {
478 i = s->method->ssl_read_bytes(s, SSL3_RT_HANDSHAKE, &recvd_type,
480 SSL3_HM_HEADER_LENGTH - s->init_num,
483 s->rwstate = SSL_READING;
486 if (recvd_type == SSL3_RT_CHANGE_CIPHER_SPEC) {
488 * A ChangeCipherSpec must be a single byte and may not occur
489 * in the middle of a handshake message.
491 if (s->init_num != 0 || readbytes != 1 || p[0] != SSL3_MT_CCS) {
492 al = SSL_AD_UNEXPECTED_MESSAGE;
493 SSLerr(SSL_F_TLS_GET_MESSAGE_HEADER,
494 SSL_R_BAD_CHANGE_CIPHER_SPEC);
497 s->s3->tmp.message_type = *mt = SSL3_MT_CHANGE_CIPHER_SPEC;
498 s->init_num = readbytes - 1;
499 s->init_msg = s->init_buf->data;
500 s->s3->tmp.message_size = readbytes;
502 } else if (recvd_type != SSL3_RT_HANDSHAKE) {
503 al = SSL_AD_UNEXPECTED_MESSAGE;
504 SSLerr(SSL_F_TLS_GET_MESSAGE_HEADER, SSL_R_CCS_RECEIVED_EARLY);
507 s->init_num += readbytes;
512 if (p[0] == SSL3_MT_HELLO_REQUEST)
514 * The server may always send 'Hello Request' messages --
515 * we are doing a handshake anyway now, so ignore them if
516 * their format is correct. Does not count for 'Finished'
519 if (p[1] == 0 && p[2] == 0 && p[3] == 0) {
524 s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE,
525 p, SSL3_HM_HEADER_LENGTH, s,
526 s->msg_callback_arg);
528 } while (skip_message);
529 /* s->init_num == SSL3_HM_HEADER_LENGTH */
532 s->s3->tmp.message_type = *(p++);
534 if (RECORD_LAYER_is_sslv2_record(&s->rlayer)) {
536 * Only happens with SSLv3+ in an SSLv2 backward compatible
539 * Total message size is the remaining record bytes to read
540 * plus the SSL3_HM_HEADER_LENGTH bytes that we already read
542 l = RECORD_LAYER_get_rrec_length(&s->rlayer)
543 + SSL3_HM_HEADER_LENGTH;
544 s->s3->tmp.message_size = l;
546 s->init_msg = s->init_buf->data;
547 s->init_num = SSL3_HM_HEADER_LENGTH;
550 /* BUF_MEM_grow takes an 'int' parameter */
551 if (l > (INT_MAX - SSL3_HM_HEADER_LENGTH)) {
552 al = SSL_AD_ILLEGAL_PARAMETER;
553 SSLerr(SSL_F_TLS_GET_MESSAGE_HEADER, SSL_R_EXCESSIVE_MESSAGE_SIZE);
556 s->s3->tmp.message_size = l;
558 s->init_msg = s->init_buf->data + SSL3_HM_HEADER_LENGTH;
564 ssl3_send_alert(s, SSL3_AL_FATAL, al);
568 int tls_get_message_body(SSL *s, size_t *len)
574 if (s->s3->tmp.message_type == SSL3_MT_CHANGE_CIPHER_SPEC) {
575 /* We've already read everything in */
576 *len = (unsigned long)s->init_num;
581 n = s->s3->tmp.message_size - s->init_num;
583 i = s->method->ssl_read_bytes(s, SSL3_RT_HANDSHAKE, NULL,
584 &p[s->init_num], n, 0, &readbytes);
586 s->rwstate = SSL_READING;
590 s->init_num += readbytes;
594 #ifndef OPENSSL_NO_NEXTPROTONEG
596 * If receiving Finished, record MAC of prior handshake messages for
597 * Finished verification.
599 if (*s->init_buf->data == SSL3_MT_FINISHED)
603 /* Feed this message into MAC computation. */
604 if (RECORD_LAYER_is_sslv2_record(&s->rlayer)) {
605 if (!ssl3_finish_mac(s, (unsigned char *)s->init_buf->data,
607 SSLerr(SSL_F_TLS_GET_MESSAGE_BODY, ERR_R_EVP_LIB);
608 ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR);
613 s->msg_callback(0, SSL2_VERSION, 0, s->init_buf->data,
614 (size_t)s->init_num, s, s->msg_callback_arg);
616 if (!ssl3_finish_mac(s, (unsigned char *)s->init_buf->data,
617 s->init_num + SSL3_HM_HEADER_LENGTH)) {
618 SSLerr(SSL_F_TLS_GET_MESSAGE_BODY, ERR_R_EVP_LIB);
619 ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR);
624 s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE, s->init_buf->data,
625 (size_t)s->init_num + SSL3_HM_HEADER_LENGTH, s,
626 s->msg_callback_arg);
633 int ssl_cert_type(const X509 *x, const EVP_PKEY *pk)
635 if (pk == NULL && (pk = X509_get0_pubkey(x)) == NULL)
638 switch (EVP_PKEY_id(pk)) {
642 return SSL_PKEY_RSA_ENC;
644 return SSL_PKEY_DSA_SIGN;
645 #ifndef OPENSSL_NO_EC
649 #ifndef OPENSSL_NO_GOST
650 case NID_id_GostR3410_2001:
651 return SSL_PKEY_GOST01;
652 case NID_id_GostR3410_2012_256:
653 return SSL_PKEY_GOST12_256;
654 case NID_id_GostR3410_2012_512:
655 return SSL_PKEY_GOST12_512;
660 int ssl_verify_alarm_type(long type)
665 case X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT:
666 case X509_V_ERR_UNABLE_TO_GET_CRL:
667 case X509_V_ERR_UNABLE_TO_GET_CRL_ISSUER:
668 al = SSL_AD_UNKNOWN_CA;
670 case X509_V_ERR_UNABLE_TO_DECRYPT_CERT_SIGNATURE:
671 case X509_V_ERR_UNABLE_TO_DECRYPT_CRL_SIGNATURE:
672 case X509_V_ERR_UNABLE_TO_DECODE_ISSUER_PUBLIC_KEY:
673 case X509_V_ERR_ERROR_IN_CERT_NOT_BEFORE_FIELD:
674 case X509_V_ERR_ERROR_IN_CERT_NOT_AFTER_FIELD:
675 case X509_V_ERR_ERROR_IN_CRL_LAST_UPDATE_FIELD:
676 case X509_V_ERR_ERROR_IN_CRL_NEXT_UPDATE_FIELD:
677 case X509_V_ERR_CERT_NOT_YET_VALID:
678 case X509_V_ERR_CRL_NOT_YET_VALID:
679 case X509_V_ERR_CERT_UNTRUSTED:
680 case X509_V_ERR_CERT_REJECTED:
681 case X509_V_ERR_HOSTNAME_MISMATCH:
682 case X509_V_ERR_EMAIL_MISMATCH:
683 case X509_V_ERR_IP_ADDRESS_MISMATCH:
684 case X509_V_ERR_DANE_NO_MATCH:
685 case X509_V_ERR_EE_KEY_TOO_SMALL:
686 case X509_V_ERR_CA_KEY_TOO_SMALL:
687 case X509_V_ERR_CA_MD_TOO_WEAK:
688 al = SSL_AD_BAD_CERTIFICATE;
690 case X509_V_ERR_CERT_SIGNATURE_FAILURE:
691 case X509_V_ERR_CRL_SIGNATURE_FAILURE:
692 al = SSL_AD_DECRYPT_ERROR;
694 case X509_V_ERR_CERT_HAS_EXPIRED:
695 case X509_V_ERR_CRL_HAS_EXPIRED:
696 al = SSL_AD_CERTIFICATE_EXPIRED;
698 case X509_V_ERR_CERT_REVOKED:
699 al = SSL_AD_CERTIFICATE_REVOKED;
701 case X509_V_ERR_UNSPECIFIED:
702 case X509_V_ERR_OUT_OF_MEM:
703 case X509_V_ERR_INVALID_CALL:
704 case X509_V_ERR_STORE_LOOKUP:
705 al = SSL_AD_INTERNAL_ERROR;
707 case X509_V_ERR_DEPTH_ZERO_SELF_SIGNED_CERT:
708 case X509_V_ERR_SELF_SIGNED_CERT_IN_CHAIN:
709 case X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT_LOCALLY:
710 case X509_V_ERR_UNABLE_TO_VERIFY_LEAF_SIGNATURE:
711 case X509_V_ERR_CERT_CHAIN_TOO_LONG:
712 case X509_V_ERR_PATH_LENGTH_EXCEEDED:
713 case X509_V_ERR_INVALID_CA:
714 al = SSL_AD_UNKNOWN_CA;
716 case X509_V_ERR_APPLICATION_VERIFICATION:
717 al = SSL_AD_HANDSHAKE_FAILURE;
719 case X509_V_ERR_INVALID_PURPOSE:
720 al = SSL_AD_UNSUPPORTED_CERTIFICATE;
723 al = SSL_AD_CERTIFICATE_UNKNOWN;
729 int ssl_allow_compression(SSL *s)
731 if (s->options & SSL_OP_NO_COMPRESSION)
733 return ssl_security(s, SSL_SECOP_COMPRESSION, 0, 0, NULL);
736 static int version_cmp(const SSL *s, int a, int b)
738 int dtls = SSL_IS_DTLS(s);
743 return a < b ? -1 : 1;
744 return DTLS_VERSION_LT(a, b) ? -1 : 1;
749 const SSL_METHOD *(*cmeth) (void);
750 const SSL_METHOD *(*smeth) (void);
753 #if TLS_MAX_VERSION != TLS1_3_VERSION
754 # error Code needs update for TLS_method() support beyond TLS1_3_VERSION.
757 static const version_info tls_version_table[] = {
758 #ifndef OPENSSL_NO_TLS1_3
759 {TLS1_3_VERSION, tlsv1_3_client_method, tlsv1_3_server_method},
761 {TLS1_3_VERSION, NULL, NULL},
763 #ifndef OPENSSL_NO_TLS1_2
764 {TLS1_2_VERSION, tlsv1_2_client_method, tlsv1_2_server_method},
766 {TLS1_2_VERSION, NULL, NULL},
768 #ifndef OPENSSL_NO_TLS1_1
769 {TLS1_1_VERSION, tlsv1_1_client_method, tlsv1_1_server_method},
771 {TLS1_1_VERSION, NULL, NULL},
773 #ifndef OPENSSL_NO_TLS1
774 {TLS1_VERSION, tlsv1_client_method, tlsv1_server_method},
776 {TLS1_VERSION, NULL, NULL},
778 #ifndef OPENSSL_NO_SSL3
779 {SSL3_VERSION, sslv3_client_method, sslv3_server_method},
781 {SSL3_VERSION, NULL, NULL},
786 #if DTLS_MAX_VERSION != DTLS1_2_VERSION
787 # error Code needs update for DTLS_method() support beyond DTLS1_2_VERSION.
790 static const version_info dtls_version_table[] = {
791 #ifndef OPENSSL_NO_DTLS1_2
792 {DTLS1_2_VERSION, dtlsv1_2_client_method, dtlsv1_2_server_method},
794 {DTLS1_2_VERSION, NULL, NULL},
796 #ifndef OPENSSL_NO_DTLS1
797 {DTLS1_VERSION, dtlsv1_client_method, dtlsv1_server_method},
798 {DTLS1_BAD_VER, dtls_bad_ver_client_method, NULL},
800 {DTLS1_VERSION, NULL, NULL},
801 {DTLS1_BAD_VER, NULL, NULL},
807 * ssl_method_error - Check whether an SSL_METHOD is enabled.
809 * @s: The SSL handle for the candidate method
810 * @method: the intended method.
812 * Returns 0 on success, or an SSL error reason on failure.
814 static int ssl_method_error(const SSL *s, const SSL_METHOD *method)
816 int version = method->version;
818 if ((s->min_proto_version != 0 &&
819 version_cmp(s, version, s->min_proto_version) < 0) ||
820 ssl_security(s, SSL_SECOP_VERSION, 0, version, NULL) == 0)
821 return SSL_R_VERSION_TOO_LOW;
823 if (s->max_proto_version != 0 &&
824 version_cmp(s, version, s->max_proto_version) > 0)
825 return SSL_R_VERSION_TOO_HIGH;
827 if ((s->options & method->mask) != 0)
828 return SSL_R_UNSUPPORTED_PROTOCOL;
829 if ((method->flags & SSL_METHOD_NO_SUITEB) != 0 && tls1_suiteb(s))
830 return SSL_R_AT_LEAST_TLS_1_2_NEEDED_IN_SUITEB_MODE;
831 else if ((method->flags & SSL_METHOD_NO_FIPS) != 0 && FIPS_mode())
832 return SSL_R_AT_LEAST_TLS_1_0_NEEDED_IN_FIPS_MODE;
838 * ssl_version_supported - Check that the specified `version` is supported by
841 * @s: The SSL handle for the candidate method
842 * @version: Protocol version to test against
844 * Returns 1 when supported, otherwise 0
846 int ssl_version_supported(const SSL *s, int version)
848 const version_info *vent;
849 const version_info *table;
851 switch (s->method->version) {
853 /* Version should match method version for non-ANY method */
854 return version_cmp(s, version, s->version) == 0;
855 case TLS_ANY_VERSION:
856 table = tls_version_table;
858 case DTLS_ANY_VERSION:
859 table = dtls_version_table;
864 vent->version != 0 && version_cmp(s, version, vent->version) <= 0;
866 if (vent->cmeth != NULL &&
867 version_cmp(s, version, vent->version) == 0 &&
868 ssl_method_error(s, vent->cmeth()) == 0) {
876 * ssl_check_version_downgrade - In response to RFC7507 SCSV version
877 * fallback indication from a client check whether we're using the highest
878 * supported protocol version.
880 * @s server SSL handle.
882 * Returns 1 when using the highest enabled version, 0 otherwise.
884 int ssl_check_version_downgrade(SSL *s)
886 const version_info *vent;
887 const version_info *table;
890 * Check that the current protocol is the highest enabled version
891 * (according to s->ctx->method, as version negotiation may have changed
894 if (s->version == s->ctx->method->version)
898 * Apparently we're using a version-flexible SSL_METHOD (not at its
899 * highest protocol version).
901 if (s->ctx->method->version == TLS_method()->version)
902 table = tls_version_table;
903 else if (s->ctx->method->version == DTLS_method()->version)
904 table = dtls_version_table;
906 /* Unexpected state; fail closed. */
910 for (vent = table; vent->version != 0; ++vent) {
911 if (vent->smeth != NULL && ssl_method_error(s, vent->smeth()) == 0)
912 return s->version == vent->version;
918 * ssl_set_version_bound - set an upper or lower bound on the supported (D)TLS
919 * protocols, provided the initial (D)TLS method is version-flexible. This
920 * function sanity-checks the proposed value and makes sure the method is
921 * version-flexible, then sets the limit if all is well.
923 * @method_version: The version of the current SSL_METHOD.
924 * @version: the intended limit.
925 * @bound: pointer to limit to be updated.
927 * Returns 1 on success, 0 on failure.
929 int ssl_set_version_bound(int method_version, int version, int *bound)
937 * Restrict TLS methods to TLS protocol versions.
938 * Restrict DTLS methods to DTLS protocol versions.
939 * Note, DTLS version numbers are decreasing, use comparison macros.
941 * Note that for both lower-bounds we use explicit versions, not
942 * (D)TLS_MIN_VERSION. This is because we don't want to break user
943 * configurations. If the MIN (supported) version ever rises, the user's
944 * "floor" remains valid even if no longer available. We don't expect the
945 * MAX ceiling to ever get lower, so making that variable makes sense.
947 switch (method_version) {
950 * XXX For fixed version methods, should we always fail and not set any
951 * bounds, always succeed and not set any bounds, or set the bounds and
952 * arrange to fail later if they are not met? At present fixed-version
953 * methods are not subject to controls that disable individual protocol
958 case TLS_ANY_VERSION:
959 if (version < SSL3_VERSION || version > TLS_MAX_VERSION)
963 case DTLS_ANY_VERSION:
964 if (DTLS_VERSION_GT(version, DTLS_MAX_VERSION) ||
965 DTLS_VERSION_LT(version, DTLS1_BAD_VER))
975 * ssl_choose_server_version - Choose server (D)TLS version. Called when the
976 * client HELLO is received to select the final server protocol version and
977 * the version specific method.
979 * @s: server SSL handle.
981 * Returns 0 on success or an SSL error reason number on failure.
983 int ssl_choose_server_version(SSL *s, CLIENTHELLO_MSG *hello)
986 * With version-flexible methods we have an initial state with:
988 * s->method->version == (D)TLS_ANY_VERSION,
989 * s->version == (D)TLS_MAX_VERSION.
991 * So we detect version-flexible methods via the method version, not the
994 int server_version = s->method->version;
995 int client_version = hello->legacy_version;
996 const version_info *vent;
997 const version_info *table;
999 RAW_EXTENSION *suppversions;
1001 s->client_version = client_version;
1003 switch (server_version) {
1005 if (version_cmp(s, client_version, s->version) < 0)
1006 return SSL_R_WRONG_SSL_VERSION;
1008 * If this SSL handle is not from a version flexible method we don't
1009 * (and never did) check min/max FIPS or Suite B constraints. Hope
1010 * that's OK. It is up to the caller to not choose fixed protocol
1011 * versions they don't want. If not, then easy to fix, just return
1012 * ssl_method_error(s, s->method)
1015 case TLS_ANY_VERSION:
1016 table = tls_version_table;
1018 case DTLS_ANY_VERSION:
1019 table = dtls_version_table;
1023 suppversions = tls_get_extension_by_type(hello->pre_proc_exts,
1024 hello->num_extensions,
1025 TLSEXT_TYPE_supported_versions);
1028 * TODO(TLS1.3): We only look at this if our max protocol version is TLS1.3
1029 * or above. Should we allow it for lower versions too?
1031 if (suppversions != NULL && !SSL_IS_DTLS(s)
1032 && (s->max_proto_version == 0
1033 || TLS1_3_VERSION <= s->max_proto_version)) {
1034 unsigned int candidate_vers = 0;
1035 unsigned int best_vers = 0;
1036 const SSL_METHOD *best_method = NULL;
1037 PACKET versionslist;
1039 if (!PACKET_as_length_prefixed_1(&suppversions->data, &versionslist)) {
1040 /* Trailing or invalid data? */
1041 return SSL_R_LENGTH_MISMATCH;
1044 while (PACKET_get_net_2(&versionslist, &candidate_vers)) {
1045 /* TODO(TLS1.3): Remove this before release */
1046 if (candidate_vers == TLS1_3_VERSION_DRAFT)
1047 candidate_vers = TLS1_3_VERSION;
1048 if ((int)candidate_vers > s->client_version)
1049 s->client_version = candidate_vers;
1050 if (version_cmp(s, candidate_vers, best_vers) <= 0)
1053 vent->version != 0 && vent->version != (int)candidate_vers;
1056 if (vent->version != 0) {
1057 const SSL_METHOD *method;
1059 method = vent->smeth();
1060 if (ssl_method_error(s, method) == 0) {
1061 best_vers = candidate_vers;
1062 best_method = method;
1066 if (PACKET_remaining(&versionslist) != 0) {
1067 /* Trailing data? */
1068 return SSL_R_LENGTH_MISMATCH;
1071 if (best_vers > 0) {
1072 s->version = best_vers;
1073 s->method = best_method;
1076 return SSL_R_UNSUPPORTED_PROTOCOL;
1080 * If the supported versions extension isn't present, then the highest
1081 * version we can negotiate is TLSv1.2
1083 if (version_cmp(s, client_version, TLS1_3_VERSION) >= 0)
1084 client_version = TLS1_2_VERSION;
1087 * No supported versions extension, so we just use the version supplied in
1090 for (vent = table; vent->version != 0; ++vent) {
1091 const SSL_METHOD *method;
1093 if (vent->smeth == NULL ||
1094 version_cmp(s, client_version, vent->version) < 0)
1096 method = vent->smeth();
1097 if (ssl_method_error(s, method) == 0) {
1098 s->version = vent->version;
1104 return disabled ? SSL_R_UNSUPPORTED_PROTOCOL : SSL_R_VERSION_TOO_LOW;
1108 * ssl_choose_client_version - Choose client (D)TLS version. Called when the
1109 * server HELLO is received to select the final client protocol version and
1110 * the version specific method.
1112 * @s: client SSL handle.
1113 * @version: The proposed version from the server's HELLO.
1115 * Returns 0 on success or an SSL error reason number on failure.
1117 int ssl_choose_client_version(SSL *s, int version)
1119 const version_info *vent;
1120 const version_info *table;
1122 switch (s->method->version) {
1124 if (version != s->version)
1125 return SSL_R_WRONG_SSL_VERSION;
1127 * If this SSL handle is not from a version flexible method we don't
1128 * (and never did) check min/max, FIPS or Suite B constraints. Hope
1129 * that's OK. It is up to the caller to not choose fixed protocol
1130 * versions they don't want. If not, then easy to fix, just return
1131 * ssl_method_error(s, s->method)
1134 case TLS_ANY_VERSION:
1135 table = tls_version_table;
1137 case DTLS_ANY_VERSION:
1138 table = dtls_version_table;
1142 for (vent = table; vent->version != 0; ++vent) {
1143 const SSL_METHOD *method;
1146 if (version != vent->version)
1148 if (vent->cmeth == NULL)
1150 method = vent->cmeth();
1151 err = ssl_method_error(s, method);
1155 s->version = version;
1159 return SSL_R_UNSUPPORTED_PROTOCOL;
1163 * ssl_get_client_min_max_version - get minimum and maximum client version
1164 * @s: The SSL connection
1165 * @min_version: The minimum supported version
1166 * @max_version: The maximum supported version
1168 * Work out what version we should be using for the initial ClientHello if the
1169 * version is initially (D)TLS_ANY_VERSION. We apply any explicit SSL_OP_NO_xxx
1170 * options, the MinProtocol and MaxProtocol configuration commands, any Suite B
1171 * or FIPS_mode() constraints and any floor imposed by the security level here,
1172 * so we don't advertise the wrong protocol version to only reject the outcome later.
1174 * Computing the right floor matters. If, e.g., TLS 1.0 and 1.2 are enabled,
1175 * TLS 1.1 is disabled, but the security level, Suite-B and/or MinProtocol
1176 * only allow TLS 1.2, we want to advertise TLS1.2, *not* TLS1.
1178 * Returns 0 on success or an SSL error reason number on failure. On failure
1179 * min_version and max_version will also be set to 0.
1181 int ssl_get_client_min_max_version(const SSL *s, int *min_version,
1186 const SSL_METHOD *single = NULL;
1187 const SSL_METHOD *method;
1188 const version_info *table;
1189 const version_info *vent;
1191 switch (s->method->version) {
1194 * If this SSL handle is not from a version flexible method we don't
1195 * (and never did) check min/max FIPS or Suite B constraints. Hope
1196 * that's OK. It is up to the caller to not choose fixed protocol
1197 * versions they don't want. If not, then easy to fix, just return
1198 * ssl_method_error(s, s->method)
1200 *min_version = *max_version = s->version;
1202 case TLS_ANY_VERSION:
1203 table = tls_version_table;
1205 case DTLS_ANY_VERSION:
1206 table = dtls_version_table;
1211 * SSL_OP_NO_X disables all protocols above X *if* there are some protocols
1212 * below X enabled. This is required in order to maintain the "version
1213 * capability" vector contiguous. Any versions with a NULL client method
1214 * (protocol version client is disabled at compile-time) is also a "hole".
1216 * Our initial state is hole == 1, version == 0. That is, versions above
1217 * the first version in the method table are disabled (a "hole" above
1218 * the valid protocol entries) and we don't have a selected version yet.
1220 * Whenever "hole == 1", and we hit an enabled method, its version becomes
1221 * the selected version, and the method becomes a candidate "single"
1222 * method. We're no longer in a hole, so "hole" becomes 0.
1224 * If "hole == 0" and we hit an enabled method, then "single" is cleared,
1225 * as we support a contiguous range of at least two methods. If we hit
1226 * a disabled method, then hole becomes true again, but nothing else
1227 * changes yet, because all the remaining methods may be disabled too.
1228 * If we again hit an enabled method after the new hole, it becomes
1229 * selected, as we start from scratch.
1231 *min_version = version = 0;
1233 for (vent = table; vent->version != 0; ++vent) {
1235 * A table entry with a NULL client method is still a hole in the
1236 * "version capability" vector.
1238 if (vent->cmeth == NULL) {
1242 method = vent->cmeth();
1243 if (ssl_method_error(s, method) != 0) {
1247 *min_version = method->version;
1249 version = (single = method)->version;
1250 *min_version = version;
1255 *max_version = version;
1257 /* Fail if everything is disabled */
1259 return SSL_R_NO_PROTOCOLS_AVAILABLE;
1265 * ssl_set_client_hello_version - Work out what version we should be using for
1266 * the initial ClientHello.
1268 * @s: client SSL handle.
1270 * Returns 0 on success or an SSL error reason number on failure.
1272 int ssl_set_client_hello_version(SSL *s)
1274 int ver_min, ver_max, ret;
1276 ret = ssl_get_client_min_max_version(s, &ver_min, &ver_max);
1281 s->client_version = s->version = ver_max;