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)
34 ret = ssl3_write_bytes(s, type, &s->init_buf->data[s->init_off],
38 if (type == SSL3_RT_HANDSHAKE)
40 * should not be done for 'Hello Request's, but in that case we'll
41 * ignore the result anyway
43 if (!ssl3_finish_mac(s,
44 (unsigned char *)&s->init_buf->data[s->init_off],
48 if (ret == s->init_num) {
50 s->msg_callback(1, s->version, type, s->init_buf->data,
51 (size_t)(s->init_off + s->init_num), s,
60 int tls_close_construct_packet(SSL *s, WPACKET *pkt)
64 if (!WPACKET_close(pkt)
65 || !WPACKET_get_length(pkt, &msglen)
67 || !WPACKET_finish(pkt))
69 s->init_num = (int)msglen;
75 int tls_construct_finished(SSL *s, const char *sender, int slen)
80 if (!WPACKET_init(&pkt, s->init_buf)
81 || !ssl_set_handshake_header2(s, &pkt, SSL3_MT_FINISHED)) {
82 SSLerr(SSL_F_TLS_CONSTRUCT_FINISHED, ERR_R_INTERNAL_ERROR);
86 i = s->method->ssl3_enc->final_finish_mac(s,
88 s->s3->tmp.finish_md);
90 SSLerr(SSL_F_TLS_CONSTRUCT_FINISHED, ERR_R_INTERNAL_ERROR);
94 s->s3->tmp.finish_md_len = i;
96 if (!WPACKET_memcpy(&pkt, s->s3->tmp.finish_md, i)) {
97 SSLerr(SSL_F_TLS_CONSTRUCT_FINISHED, ERR_R_INTERNAL_ERROR);
102 * Copy the finished so we can use it for renegotiation checks
105 OPENSSL_assert(i <= EVP_MAX_MD_SIZE);
106 memcpy(s->s3->previous_client_finished, s->s3->tmp.finish_md, i);
107 s->s3->previous_client_finished_len = i;
109 OPENSSL_assert(i <= EVP_MAX_MD_SIZE);
110 memcpy(s->s3->previous_server_finished, s->s3->tmp.finish_md, i);
111 s->s3->previous_server_finished_len = i;
114 if (!ssl_close_construct_packet(s, &pkt)) {
115 SSLerr(SSL_F_TLS_CONSTRUCT_FINISHED, ERR_R_INTERNAL_ERROR);
121 ossl_statem_set_error(s);
122 WPACKET_cleanup(&pkt);
123 ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR);
127 #ifndef OPENSSL_NO_NEXTPROTONEG
129 * ssl3_take_mac calculates the Finished MAC for the handshakes messages seen
132 static void ssl3_take_mac(SSL *s)
137 * If no new cipher setup return immediately: other functions will set
138 * the appropriate error.
140 if (s->s3->tmp.new_cipher == NULL)
143 sender = s->method->ssl3_enc->server_finished_label;
144 slen = s->method->ssl3_enc->server_finished_label_len;
146 sender = s->method->ssl3_enc->client_finished_label;
147 slen = s->method->ssl3_enc->client_finished_label_len;
150 s->s3->tmp.peer_finish_md_len = s->method->ssl3_enc->final_finish_mac(s,
153 s->s3->tmp.peer_finish_md);
157 MSG_PROCESS_RETURN tls_process_change_cipher_spec(SSL *s, PACKET *pkt)
162 remain = PACKET_remaining(pkt);
164 * 'Change Cipher Spec' is just a single byte, which should already have
165 * been consumed by ssl_get_message() so there should be no bytes left,
166 * unless we're using DTLS1_BAD_VER, which has an extra 2 bytes
168 if (SSL_IS_DTLS(s)) {
169 if ((s->version == DTLS1_BAD_VER
170 && remain != DTLS1_CCS_HEADER_LENGTH + 1)
171 || (s->version != DTLS1_BAD_VER
172 && remain != DTLS1_CCS_HEADER_LENGTH - 1)) {
173 al = SSL_AD_ILLEGAL_PARAMETER;
174 SSLerr(SSL_F_TLS_PROCESS_CHANGE_CIPHER_SPEC,
175 SSL_R_BAD_CHANGE_CIPHER_SPEC);
180 al = SSL_AD_ILLEGAL_PARAMETER;
181 SSLerr(SSL_F_TLS_PROCESS_CHANGE_CIPHER_SPEC,
182 SSL_R_BAD_CHANGE_CIPHER_SPEC);
187 /* Check we have a cipher to change to */
188 if (s->s3->tmp.new_cipher == NULL) {
189 al = SSL_AD_UNEXPECTED_MESSAGE;
190 SSLerr(SSL_F_TLS_PROCESS_CHANGE_CIPHER_SPEC, SSL_R_CCS_RECEIVED_EARLY);
194 s->s3->change_cipher_spec = 1;
195 if (!ssl3_do_change_cipher_spec(s)) {
196 al = SSL_AD_INTERNAL_ERROR;
197 SSLerr(SSL_F_TLS_PROCESS_CHANGE_CIPHER_SPEC, ERR_R_INTERNAL_ERROR);
201 if (SSL_IS_DTLS(s)) {
202 dtls1_reset_seq_numbers(s, SSL3_CC_READ);
204 if (s->version == DTLS1_BAD_VER)
205 s->d1->handshake_read_seq++;
207 #ifndef OPENSSL_NO_SCTP
209 * Remember that a CCS has been received, so that an old key of
210 * SCTP-Auth can be deleted when a CCS is sent. Will be ignored if no
213 BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_AUTH_CCS_RCVD, 1, NULL);
217 return MSG_PROCESS_CONTINUE_READING;
219 ssl3_send_alert(s, SSL3_AL_FATAL, al);
220 ossl_statem_set_error(s);
221 return MSG_PROCESS_ERROR;
224 MSG_PROCESS_RETURN tls_process_finished(SSL *s, PACKET *pkt)
228 /* If this occurs, we have missed a message */
229 if (!s->s3->change_cipher_spec) {
230 al = SSL_AD_UNEXPECTED_MESSAGE;
231 SSLerr(SSL_F_TLS_PROCESS_FINISHED, SSL_R_GOT_A_FIN_BEFORE_A_CCS);
234 s->s3->change_cipher_spec = 0;
236 i = s->s3->tmp.peer_finish_md_len;
238 if ((unsigned long)i != PACKET_remaining(pkt)) {
239 al = SSL_AD_DECODE_ERROR;
240 SSLerr(SSL_F_TLS_PROCESS_FINISHED, SSL_R_BAD_DIGEST_LENGTH);
244 if (CRYPTO_memcmp(PACKET_data(pkt), s->s3->tmp.peer_finish_md, i) != 0) {
245 al = SSL_AD_DECRYPT_ERROR;
246 SSLerr(SSL_F_TLS_PROCESS_FINISHED, SSL_R_DIGEST_CHECK_FAILED);
251 * Copy the finished so we can use it for renegotiation checks
254 OPENSSL_assert(i <= EVP_MAX_MD_SIZE);
255 memcpy(s->s3->previous_client_finished, s->s3->tmp.peer_finish_md, i);
256 s->s3->previous_client_finished_len = i;
258 OPENSSL_assert(i <= EVP_MAX_MD_SIZE);
259 memcpy(s->s3->previous_server_finished, s->s3->tmp.peer_finish_md, i);
260 s->s3->previous_server_finished_len = i;
263 return MSG_PROCESS_FINISHED_READING;
265 ssl3_send_alert(s, SSL3_AL_FATAL, al);
266 ossl_statem_set_error(s);
267 return MSG_PROCESS_ERROR;
270 int tls_construct_change_cipher_spec(SSL *s)
274 if (!WPACKET_init(&pkt, s->init_buf)
275 || !WPACKET_put_bytes(&pkt, SSL3_MT_CCS, 1)
276 || !WPACKET_finish(&pkt)) {
277 WPACKET_cleanup(&pkt);
278 ossl_statem_set_error(s);
279 SSLerr(SSL_F_TLS_CONSTRUCT_FINISHED, ERR_R_INTERNAL_ERROR);
280 ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR);
290 unsigned long ssl3_output_cert_chain(SSL *s, CERT_PKEY *cpk)
294 if (!WPACKET_init(&pkt, s->init_buf)) {
295 /* Should not happen */
296 SSLerr(SSL_F_SSL3_OUTPUT_CERT_CHAIN, ERR_R_INTERNAL_ERROR);
300 if (!ssl_set_handshake_header2(s, &pkt, SSL3_MT_CERTIFICATE)
301 || !WPACKET_start_sub_packet_u24(&pkt)) {
302 SSLerr(SSL_F_SSL3_OUTPUT_CERT_CHAIN, ERR_R_INTERNAL_ERROR);
306 if (!ssl_add_cert_chain(s, &pkt, cpk))
309 if (!WPACKET_close(&pkt) || !ssl_close_construct_packet(s, &pkt)) {
310 SSLerr(SSL_F_SSL3_OUTPUT_CERT_CHAIN, ERR_R_INTERNAL_ERROR);
315 WPACKET_cleanup(&pkt);
319 WORK_STATE tls_finish_handshake(SSL *s, WORK_STATE wst)
321 void (*cb) (const SSL *ssl, int type, int val) = NULL;
323 #ifndef OPENSSL_NO_SCTP
324 if (SSL_IS_DTLS(s) && BIO_dgram_is_sctp(SSL_get_wbio(s))) {
326 ret = dtls_wait_for_dry(s);
327 if (ret != WORK_FINISHED_CONTINUE)
332 /* clean a few things up */
333 ssl3_cleanup_key_block(s);
335 if (!SSL_IS_DTLS(s)) {
337 * We don't do this in DTLS because we may still need the init_buf
338 * in case there are any unexpected retransmits
340 BUF_MEM_free(s->init_buf);
344 ssl_free_wbio_buffer(s);
348 if (!s->server || s->renegotiate == 2) {
349 /* skipped if we just sent a HelloRequest */
354 ssl_update_cache(s, SSL_SESS_CACHE_SERVER);
356 s->ctx->stats.sess_accept_good++;
357 s->handshake_func = ossl_statem_accept;
359 ssl_update_cache(s, SSL_SESS_CACHE_CLIENT);
361 s->ctx->stats.sess_hit++;
363 s->handshake_func = ossl_statem_connect;
364 s->ctx->stats.sess_connect_good++;
367 if (s->info_callback != NULL)
368 cb = s->info_callback;
369 else if (s->ctx->info_callback != NULL)
370 cb = s->ctx->info_callback;
373 cb(s, SSL_CB_HANDSHAKE_DONE, 1);
375 if (SSL_IS_DTLS(s)) {
376 /* done with handshaking */
377 s->d1->handshake_read_seq = 0;
378 s->d1->handshake_write_seq = 0;
379 s->d1->next_handshake_write_seq = 0;
380 dtls1_clear_received_buffer(s);
384 return WORK_FINISHED_STOP;
387 int tls_get_message_header(SSL *s, int *mt)
389 /* s->init_num < SSL3_HM_HEADER_LENGTH */
390 int skip_message, i, recvd_type, al;
394 p = (unsigned char *)s->init_buf->data;
397 while (s->init_num < SSL3_HM_HEADER_LENGTH) {
398 i = s->method->ssl_read_bytes(s, SSL3_RT_HANDSHAKE, &recvd_type,
400 SSL3_HM_HEADER_LENGTH - s->init_num,
403 s->rwstate = SSL_READING;
406 if (recvd_type == SSL3_RT_CHANGE_CIPHER_SPEC) {
408 * A ChangeCipherSpec must be a single byte and may not occur
409 * in the middle of a handshake message.
411 if (s->init_num != 0 || i != 1 || p[0] != SSL3_MT_CCS) {
412 al = SSL_AD_UNEXPECTED_MESSAGE;
413 SSLerr(SSL_F_TLS_GET_MESSAGE_HEADER,
414 SSL_R_BAD_CHANGE_CIPHER_SPEC);
417 s->s3->tmp.message_type = *mt = SSL3_MT_CHANGE_CIPHER_SPEC;
419 s->s3->tmp.message_size = i;
421 } else if (recvd_type != SSL3_RT_HANDSHAKE) {
422 al = SSL_AD_UNEXPECTED_MESSAGE;
423 SSLerr(SSL_F_TLS_GET_MESSAGE_HEADER, SSL_R_CCS_RECEIVED_EARLY);
431 if (p[0] == SSL3_MT_HELLO_REQUEST)
433 * The server may always send 'Hello Request' messages --
434 * we are doing a handshake anyway now, so ignore them if
435 * their format is correct. Does not count for 'Finished'
438 if (p[1] == 0 && p[2] == 0 && p[3] == 0) {
443 s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE,
444 p, SSL3_HM_HEADER_LENGTH, s,
445 s->msg_callback_arg);
447 } while (skip_message);
448 /* s->init_num == SSL3_HM_HEADER_LENGTH */
451 s->s3->tmp.message_type = *(p++);
453 if (RECORD_LAYER_is_sslv2_record(&s->rlayer)) {
455 * Only happens with SSLv3+ in an SSLv2 backward compatible
458 * Total message size is the remaining record bytes to read
459 * plus the SSL3_HM_HEADER_LENGTH bytes that we already read
461 l = RECORD_LAYER_get_rrec_length(&s->rlayer)
462 + SSL3_HM_HEADER_LENGTH;
463 if (l && !BUF_MEM_grow_clean(s->init_buf, (int)l)) {
464 SSLerr(SSL_F_TLS_GET_MESSAGE_HEADER, ERR_R_BUF_LIB);
467 s->s3->tmp.message_size = l;
469 s->init_msg = s->init_buf->data;
470 s->init_num = SSL3_HM_HEADER_LENGTH;
473 /* BUF_MEM_grow takes an 'int' parameter */
474 if (l > (INT_MAX - SSL3_HM_HEADER_LENGTH)) {
475 al = SSL_AD_ILLEGAL_PARAMETER;
476 SSLerr(SSL_F_TLS_GET_MESSAGE_HEADER, SSL_R_EXCESSIVE_MESSAGE_SIZE);
479 if (l && !BUF_MEM_grow_clean(s->init_buf,
480 (int)l + SSL3_HM_HEADER_LENGTH)) {
481 SSLerr(SSL_F_TLS_GET_MESSAGE_HEADER, ERR_R_BUF_LIB);
484 s->s3->tmp.message_size = l;
486 s->init_msg = s->init_buf->data + SSL3_HM_HEADER_LENGTH;
492 ssl3_send_alert(s, SSL3_AL_FATAL, al);
497 int tls_get_message_body(SSL *s, unsigned long *len)
503 if (s->s3->tmp.message_type == SSL3_MT_CHANGE_CIPHER_SPEC) {
504 /* We've already read everything in */
505 *len = (unsigned long)s->init_num;
510 n = s->s3->tmp.message_size - s->init_num;
512 i = s->method->ssl_read_bytes(s, SSL3_RT_HANDSHAKE, NULL,
513 &p[s->init_num], n, 0);
515 s->rwstate = SSL_READING;
523 #ifndef OPENSSL_NO_NEXTPROTONEG
525 * If receiving Finished, record MAC of prior handshake messages for
526 * Finished verification.
528 if (*s->init_buf->data == SSL3_MT_FINISHED)
532 /* Feed this message into MAC computation. */
533 if (RECORD_LAYER_is_sslv2_record(&s->rlayer)) {
534 if (!ssl3_finish_mac(s, (unsigned char *)s->init_buf->data,
536 SSLerr(SSL_F_TLS_GET_MESSAGE_BODY, ERR_R_EVP_LIB);
537 ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR);
542 s->msg_callback(0, SSL2_VERSION, 0, s->init_buf->data,
543 (size_t)s->init_num, s, s->msg_callback_arg);
545 if (!ssl3_finish_mac(s, (unsigned char *)s->init_buf->data,
546 s->init_num + SSL3_HM_HEADER_LENGTH)) {
547 SSLerr(SSL_F_TLS_GET_MESSAGE_BODY, ERR_R_EVP_LIB);
548 ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR);
553 s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE, s->init_buf->data,
554 (size_t)s->init_num + SSL3_HM_HEADER_LENGTH, s,
555 s->msg_callback_arg);
559 * init_num should never be negative...should probably be declared
562 if (s->init_num < 0) {
563 SSLerr(SSL_F_TLS_GET_MESSAGE_BODY, ERR_R_INTERNAL_ERROR);
564 ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR);
568 *len = (unsigned long)s->init_num;
572 int ssl_cert_type(const X509 *x, const EVP_PKEY *pk)
574 if (pk == NULL && (pk = X509_get0_pubkey(x)) == NULL)
577 switch (EVP_PKEY_id(pk)) {
581 return SSL_PKEY_RSA_ENC;
583 return SSL_PKEY_DSA_SIGN;
584 #ifndef OPENSSL_NO_EC
588 #ifndef OPENSSL_NO_GOST
589 case NID_id_GostR3410_2001:
590 return SSL_PKEY_GOST01;
591 case NID_id_GostR3410_2012_256:
592 return SSL_PKEY_GOST12_256;
593 case NID_id_GostR3410_2012_512:
594 return SSL_PKEY_GOST12_512;
599 int ssl_verify_alarm_type(long type)
604 case X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT:
605 case X509_V_ERR_UNABLE_TO_GET_CRL:
606 case X509_V_ERR_UNABLE_TO_GET_CRL_ISSUER:
607 al = SSL_AD_UNKNOWN_CA;
609 case X509_V_ERR_UNABLE_TO_DECRYPT_CERT_SIGNATURE:
610 case X509_V_ERR_UNABLE_TO_DECRYPT_CRL_SIGNATURE:
611 case X509_V_ERR_UNABLE_TO_DECODE_ISSUER_PUBLIC_KEY:
612 case X509_V_ERR_ERROR_IN_CERT_NOT_BEFORE_FIELD:
613 case X509_V_ERR_ERROR_IN_CERT_NOT_AFTER_FIELD:
614 case X509_V_ERR_ERROR_IN_CRL_LAST_UPDATE_FIELD:
615 case X509_V_ERR_ERROR_IN_CRL_NEXT_UPDATE_FIELD:
616 case X509_V_ERR_CERT_NOT_YET_VALID:
617 case X509_V_ERR_CRL_NOT_YET_VALID:
618 case X509_V_ERR_CERT_UNTRUSTED:
619 case X509_V_ERR_CERT_REJECTED:
620 case X509_V_ERR_HOSTNAME_MISMATCH:
621 case X509_V_ERR_EMAIL_MISMATCH:
622 case X509_V_ERR_IP_ADDRESS_MISMATCH:
623 case X509_V_ERR_DANE_NO_MATCH:
624 case X509_V_ERR_EE_KEY_TOO_SMALL:
625 case X509_V_ERR_CA_KEY_TOO_SMALL:
626 case X509_V_ERR_CA_MD_TOO_WEAK:
627 al = SSL_AD_BAD_CERTIFICATE;
629 case X509_V_ERR_CERT_SIGNATURE_FAILURE:
630 case X509_V_ERR_CRL_SIGNATURE_FAILURE:
631 al = SSL_AD_DECRYPT_ERROR;
633 case X509_V_ERR_CERT_HAS_EXPIRED:
634 case X509_V_ERR_CRL_HAS_EXPIRED:
635 al = SSL_AD_CERTIFICATE_EXPIRED;
637 case X509_V_ERR_CERT_REVOKED:
638 al = SSL_AD_CERTIFICATE_REVOKED;
640 case X509_V_ERR_UNSPECIFIED:
641 case X509_V_ERR_OUT_OF_MEM:
642 case X509_V_ERR_INVALID_CALL:
643 case X509_V_ERR_STORE_LOOKUP:
644 al = SSL_AD_INTERNAL_ERROR;
646 case X509_V_ERR_DEPTH_ZERO_SELF_SIGNED_CERT:
647 case X509_V_ERR_SELF_SIGNED_CERT_IN_CHAIN:
648 case X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT_LOCALLY:
649 case X509_V_ERR_UNABLE_TO_VERIFY_LEAF_SIGNATURE:
650 case X509_V_ERR_CERT_CHAIN_TOO_LONG:
651 case X509_V_ERR_PATH_LENGTH_EXCEEDED:
652 case X509_V_ERR_INVALID_CA:
653 al = SSL_AD_UNKNOWN_CA;
655 case X509_V_ERR_APPLICATION_VERIFICATION:
656 al = SSL_AD_HANDSHAKE_FAILURE;
658 case X509_V_ERR_INVALID_PURPOSE:
659 al = SSL_AD_UNSUPPORTED_CERTIFICATE;
662 al = SSL_AD_CERTIFICATE_UNKNOWN;
668 int ssl_allow_compression(SSL *s)
670 if (s->options & SSL_OP_NO_COMPRESSION)
672 return ssl_security(s, SSL_SECOP_COMPRESSION, 0, 0, NULL);
675 static int version_cmp(const SSL *s, int a, int b)
677 int dtls = SSL_IS_DTLS(s);
682 return a < b ? -1 : 1;
683 return DTLS_VERSION_LT(a, b) ? -1 : 1;
688 const SSL_METHOD *(*cmeth) (void);
689 const SSL_METHOD *(*smeth) (void);
692 #if TLS_MAX_VERSION != TLS1_2_VERSION
693 # error Code needs update for TLS_method() support beyond TLS1_2_VERSION.
696 static const version_info tls_version_table[] = {
697 #ifndef OPENSSL_NO_TLS1_2
698 {TLS1_2_VERSION, tlsv1_2_client_method, tlsv1_2_server_method},
700 {TLS1_2_VERSION, NULL, NULL},
702 #ifndef OPENSSL_NO_TLS1_1
703 {TLS1_1_VERSION, tlsv1_1_client_method, tlsv1_1_server_method},
705 {TLS1_1_VERSION, NULL, NULL},
707 #ifndef OPENSSL_NO_TLS1
708 {TLS1_VERSION, tlsv1_client_method, tlsv1_server_method},
710 {TLS1_VERSION, NULL, NULL},
712 #ifndef OPENSSL_NO_SSL3
713 {SSL3_VERSION, sslv3_client_method, sslv3_server_method},
715 {SSL3_VERSION, NULL, NULL},
720 #if DTLS_MAX_VERSION != DTLS1_2_VERSION
721 # error Code needs update for DTLS_method() support beyond DTLS1_2_VERSION.
724 static const version_info dtls_version_table[] = {
725 #ifndef OPENSSL_NO_DTLS1_2
726 {DTLS1_2_VERSION, dtlsv1_2_client_method, dtlsv1_2_server_method},
728 {DTLS1_2_VERSION, NULL, NULL},
730 #ifndef OPENSSL_NO_DTLS1
731 {DTLS1_VERSION, dtlsv1_client_method, dtlsv1_server_method},
732 {DTLS1_BAD_VER, dtls_bad_ver_client_method, NULL},
734 {DTLS1_VERSION, NULL, NULL},
735 {DTLS1_BAD_VER, NULL, NULL},
741 * ssl_method_error - Check whether an SSL_METHOD is enabled.
743 * @s: The SSL handle for the candidate method
744 * @method: the intended method.
746 * Returns 0 on success, or an SSL error reason on failure.
748 static int ssl_method_error(const SSL *s, const SSL_METHOD *method)
750 int version = method->version;
752 if ((s->min_proto_version != 0 &&
753 version_cmp(s, version, s->min_proto_version) < 0) ||
754 ssl_security(s, SSL_SECOP_VERSION, 0, version, NULL) == 0)
755 return SSL_R_VERSION_TOO_LOW;
757 if (s->max_proto_version != 0 &&
758 version_cmp(s, version, s->max_proto_version) > 0)
759 return SSL_R_VERSION_TOO_HIGH;
761 if ((s->options & method->mask) != 0)
762 return SSL_R_UNSUPPORTED_PROTOCOL;
763 if ((method->flags & SSL_METHOD_NO_SUITEB) != 0 && tls1_suiteb(s))
764 return SSL_R_AT_LEAST_TLS_1_2_NEEDED_IN_SUITEB_MODE;
765 else if ((method->flags & SSL_METHOD_NO_FIPS) != 0 && FIPS_mode())
766 return SSL_R_AT_LEAST_TLS_1_0_NEEDED_IN_FIPS_MODE;
772 * ssl_version_supported - Check that the specified `version` is supported by
775 * @s: The SSL handle for the candidate method
776 * @version: Protocol version to test against
778 * Returns 1 when supported, otherwise 0
780 int ssl_version_supported(const SSL *s, int version)
782 const version_info *vent;
783 const version_info *table;
785 switch (s->method->version) {
787 /* Version should match method version for non-ANY method */
788 return version_cmp(s, version, s->version) == 0;
789 case TLS_ANY_VERSION:
790 table = tls_version_table;
792 case DTLS_ANY_VERSION:
793 table = dtls_version_table;
798 vent->version != 0 && version_cmp(s, version, vent->version) <= 0;
800 if (vent->cmeth != NULL &&
801 version_cmp(s, version, vent->version) == 0 &&
802 ssl_method_error(s, vent->cmeth()) == 0) {
810 * ssl_check_version_downgrade - In response to RFC7507 SCSV version
811 * fallback indication from a client check whether we're using the highest
812 * supported protocol version.
814 * @s server SSL handle.
816 * Returns 1 when using the highest enabled version, 0 otherwise.
818 int ssl_check_version_downgrade(SSL *s)
820 const version_info *vent;
821 const version_info *table;
824 * Check that the current protocol is the highest enabled version
825 * (according to s->ctx->method, as version negotiation may have changed
828 if (s->version == s->ctx->method->version)
832 * Apparently we're using a version-flexible SSL_METHOD (not at its
833 * highest protocol version).
835 if (s->ctx->method->version == TLS_method()->version)
836 table = tls_version_table;
837 else if (s->ctx->method->version == DTLS_method()->version)
838 table = dtls_version_table;
840 /* Unexpected state; fail closed. */
844 for (vent = table; vent->version != 0; ++vent) {
845 if (vent->smeth != NULL && ssl_method_error(s, vent->smeth()) == 0)
846 return s->version == vent->version;
852 * ssl_set_version_bound - set an upper or lower bound on the supported (D)TLS
853 * protocols, provided the initial (D)TLS method is version-flexible. This
854 * function sanity-checks the proposed value and makes sure the method is
855 * version-flexible, then sets the limit if all is well.
857 * @method_version: The version of the current SSL_METHOD.
858 * @version: the intended limit.
859 * @bound: pointer to limit to be updated.
861 * Returns 1 on success, 0 on failure.
863 int ssl_set_version_bound(int method_version, int version, int *bound)
871 * Restrict TLS methods to TLS protocol versions.
872 * Restrict DTLS methods to DTLS protocol versions.
873 * Note, DTLS version numbers are decreasing, use comparison macros.
875 * Note that for both lower-bounds we use explicit versions, not
876 * (D)TLS_MIN_VERSION. This is because we don't want to break user
877 * configurations. If the MIN (supported) version ever rises, the user's
878 * "floor" remains valid even if no longer available. We don't expect the
879 * MAX ceiling to ever get lower, so making that variable makes sense.
881 switch (method_version) {
884 * XXX For fixed version methods, should we always fail and not set any
885 * bounds, always succeed and not set any bounds, or set the bounds and
886 * arrange to fail later if they are not met? At present fixed-version
887 * methods are not subject to controls that disable individual protocol
892 case TLS_ANY_VERSION:
893 if (version < SSL3_VERSION || version > TLS_MAX_VERSION)
897 case DTLS_ANY_VERSION:
898 if (DTLS_VERSION_GT(version, DTLS_MAX_VERSION) ||
899 DTLS_VERSION_LT(version, DTLS1_BAD_VER))
909 * ssl_choose_server_version - Choose server (D)TLS version. Called when the
910 * client HELLO is received to select the final server protocol version and
911 * the version specific method.
913 * @s: server SSL handle.
915 * Returns 0 on success or an SSL error reason number on failure.
917 int ssl_choose_server_version(SSL *s)
920 * With version-flexible methods we have an initial state with:
922 * s->method->version == (D)TLS_ANY_VERSION,
923 * s->version == (D)TLS_MAX_VERSION.
925 * So we detect version-flexible methods via the method version, not the
928 int server_version = s->method->version;
929 int client_version = s->client_version;
930 const version_info *vent;
931 const version_info *table;
934 switch (server_version) {
936 if (version_cmp(s, client_version, s->version) < 0)
937 return SSL_R_WRONG_SSL_VERSION;
939 * If this SSL handle is not from a version flexible method we don't
940 * (and never did) check min/max FIPS or Suite B constraints. Hope
941 * that's OK. It is up to the caller to not choose fixed protocol
942 * versions they don't want. If not, then easy to fix, just return
943 * ssl_method_error(s, s->method)
946 case TLS_ANY_VERSION:
947 table = tls_version_table;
949 case DTLS_ANY_VERSION:
950 table = dtls_version_table;
954 for (vent = table; vent->version != 0; ++vent) {
955 const SSL_METHOD *method;
957 if (vent->smeth == NULL ||
958 version_cmp(s, client_version, vent->version) < 0)
960 method = vent->smeth();
961 if (ssl_method_error(s, method) == 0) {
962 s->version = vent->version;
968 return disabled ? SSL_R_UNSUPPORTED_PROTOCOL : SSL_R_VERSION_TOO_LOW;
972 * ssl_choose_client_version - Choose client (D)TLS version. Called when the
973 * server HELLO is received to select the final client protocol version and
974 * the version specific method.
976 * @s: client SSL handle.
977 * @version: The proposed version from the server's HELLO.
979 * Returns 0 on success or an SSL error reason number on failure.
981 int ssl_choose_client_version(SSL *s, int version)
983 const version_info *vent;
984 const version_info *table;
986 switch (s->method->version) {
988 if (version != s->version)
989 return SSL_R_WRONG_SSL_VERSION;
991 * If this SSL handle is not from a version flexible method we don't
992 * (and never did) check min/max, FIPS or Suite B constraints. Hope
993 * that's OK. It is up to the caller to not choose fixed protocol
994 * versions they don't want. If not, then easy to fix, just return
995 * ssl_method_error(s, s->method)
998 case TLS_ANY_VERSION:
999 table = tls_version_table;
1001 case DTLS_ANY_VERSION:
1002 table = dtls_version_table;
1006 for (vent = table; vent->version != 0; ++vent) {
1007 const SSL_METHOD *method;
1010 if (version != vent->version)
1012 if (vent->cmeth == NULL)
1014 method = vent->cmeth();
1015 err = ssl_method_error(s, method);
1019 s->version = version;
1023 return SSL_R_UNSUPPORTED_PROTOCOL;
1027 * ssl_get_client_min_max_version - get minimum and maximum client version
1028 * @s: The SSL connection
1029 * @min_version: The minimum supported version
1030 * @max_version: The maximum supported version
1032 * Work out what version we should be using for the initial ClientHello if the
1033 * version is initially (D)TLS_ANY_VERSION. We apply any explicit SSL_OP_NO_xxx
1034 * options, the MinProtocol and MaxProtocol configuration commands, any Suite B
1035 * or FIPS_mode() constraints and any floor imposed by the security level here,
1036 * so we don't advertise the wrong protocol version to only reject the outcome later.
1038 * Computing the right floor matters. If, e.g., TLS 1.0 and 1.2 are enabled,
1039 * TLS 1.1 is disabled, but the security level, Suite-B and/or MinProtocol
1040 * only allow TLS 1.2, we want to advertise TLS1.2, *not* TLS1.
1042 * Returns 0 on success or an SSL error reason number on failure. On failure
1043 * min_version and max_version will also be set to 0.
1045 int ssl_get_client_min_max_version(const SSL *s, int *min_version,
1050 const SSL_METHOD *single = NULL;
1051 const SSL_METHOD *method;
1052 const version_info *table;
1053 const version_info *vent;
1055 switch (s->method->version) {
1058 * If this SSL handle is not from a version flexible method we don't
1059 * (and never did) check min/max FIPS or Suite B constraints. Hope
1060 * that's OK. It is up to the caller to not choose fixed protocol
1061 * versions they don't want. If not, then easy to fix, just return
1062 * ssl_method_error(s, s->method)
1064 *min_version = *max_version = s->version;
1066 case TLS_ANY_VERSION:
1067 table = tls_version_table;
1069 case DTLS_ANY_VERSION:
1070 table = dtls_version_table;
1075 * SSL_OP_NO_X disables all protocols above X *if* there are some protocols
1076 * below X enabled. This is required in order to maintain the "version
1077 * capability" vector contiguous. Any versions with a NULL client method
1078 * (protocol version client is disabled at compile-time) is also a "hole".
1080 * Our initial state is hole == 1, version == 0. That is, versions above
1081 * the first version in the method table are disabled (a "hole" above
1082 * the valid protocol entries) and we don't have a selected version yet.
1084 * Whenever "hole == 1", and we hit an enabled method, its version becomes
1085 * the selected version, and the method becomes a candidate "single"
1086 * method. We're no longer in a hole, so "hole" becomes 0.
1088 * If "hole == 0" and we hit an enabled method, then "single" is cleared,
1089 * as we support a contiguous range of at least two methods. If we hit
1090 * a disabled method, then hole becomes true again, but nothing else
1091 * changes yet, because all the remaining methods may be disabled too.
1092 * If we again hit an enabled method after the new hole, it becomes
1093 * selected, as we start from scratch.
1095 *min_version = version = 0;
1097 for (vent = table; vent->version != 0; ++vent) {
1099 * A table entry with a NULL client method is still a hole in the
1100 * "version capability" vector.
1102 if (vent->cmeth == NULL) {
1106 method = vent->cmeth();
1107 if (ssl_method_error(s, method) != 0) {
1111 *min_version = method->version;
1113 version = (single = method)->version;
1114 *min_version = version;
1119 *max_version = version;
1121 /* Fail if everything is disabled */
1123 return SSL_R_NO_PROTOCOLS_AVAILABLE;
1129 * ssl_set_client_hello_version - Work out what version we should be using for
1130 * the initial ClientHello.
1132 * @s: client SSL handle.
1134 * Returns 0 on success or an SSL error reason number on failure.
1136 int ssl_set_client_hello_version(SSL *s)
1138 int ver_min, ver_max, ret;
1140 ret = ssl_get_client_min_max_version(s, &ver_min, &ver_max);
1145 s->client_version = s->version = ver_max;