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)
81 p = ssl_handshake_start(s);
83 i = s->method->ssl3_enc->final_finish_mac(s,
85 s->s3->tmp.finish_md);
88 s->s3->tmp.finish_md_len = i;
89 memcpy(p, s->s3->tmp.finish_md, i);
93 * Copy the finished so we can use it for renegotiation checks
96 OPENSSL_assert(i <= EVP_MAX_MD_SIZE);
97 memcpy(s->s3->previous_client_finished, s->s3->tmp.finish_md, i);
98 s->s3->previous_client_finished_len = i;
100 OPENSSL_assert(i <= EVP_MAX_MD_SIZE);
101 memcpy(s->s3->previous_server_finished, s->s3->tmp.finish_md, i);
102 s->s3->previous_server_finished_len = i;
105 if (!ssl_set_handshake_header(s, SSL3_MT_FINISHED, l)) {
106 SSLerr(SSL_F_TLS_CONSTRUCT_FINISHED, ERR_R_INTERNAL_ERROR);
113 #ifndef OPENSSL_NO_NEXTPROTONEG
115 * ssl3_take_mac calculates the Finished MAC for the handshakes messages seen
118 static void ssl3_take_mac(SSL *s)
123 * If no new cipher setup return immediately: other functions will set
124 * the appropriate error.
126 if (s->s3->tmp.new_cipher == NULL)
129 sender = s->method->ssl3_enc->server_finished_label;
130 slen = s->method->ssl3_enc->server_finished_label_len;
132 sender = s->method->ssl3_enc->client_finished_label;
133 slen = s->method->ssl3_enc->client_finished_label_len;
136 s->s3->tmp.peer_finish_md_len = s->method->ssl3_enc->final_finish_mac(s,
139 s->s3->tmp.peer_finish_md);
143 MSG_PROCESS_RETURN tls_process_change_cipher_spec(SSL *s, PACKET *pkt)
148 remain = PACKET_remaining(pkt);
150 * 'Change Cipher Spec' is just a single byte, which should already have
151 * been consumed by ssl_get_message() so there should be no bytes left,
152 * unless we're using DTLS1_BAD_VER, which has an extra 2 bytes
154 if (SSL_IS_DTLS(s)) {
155 if ((s->version == DTLS1_BAD_VER
156 && remain != DTLS1_CCS_HEADER_LENGTH + 1)
157 || (s->version != DTLS1_BAD_VER
158 && remain != DTLS1_CCS_HEADER_LENGTH - 1)) {
159 al = SSL_AD_ILLEGAL_PARAMETER;
160 SSLerr(SSL_F_TLS_PROCESS_CHANGE_CIPHER_SPEC,
161 SSL_R_BAD_CHANGE_CIPHER_SPEC);
166 al = SSL_AD_ILLEGAL_PARAMETER;
167 SSLerr(SSL_F_TLS_PROCESS_CHANGE_CIPHER_SPEC,
168 SSL_R_BAD_CHANGE_CIPHER_SPEC);
173 /* Check we have a cipher to change to */
174 if (s->s3->tmp.new_cipher == NULL) {
175 al = SSL_AD_UNEXPECTED_MESSAGE;
176 SSLerr(SSL_F_TLS_PROCESS_CHANGE_CIPHER_SPEC, SSL_R_CCS_RECEIVED_EARLY);
180 s->s3->change_cipher_spec = 1;
181 if (!ssl3_do_change_cipher_spec(s)) {
182 al = SSL_AD_INTERNAL_ERROR;
183 SSLerr(SSL_F_TLS_PROCESS_CHANGE_CIPHER_SPEC, ERR_R_INTERNAL_ERROR);
187 if (SSL_IS_DTLS(s)) {
188 dtls1_reset_seq_numbers(s, SSL3_CC_READ);
190 if (s->version == DTLS1_BAD_VER)
191 s->d1->handshake_read_seq++;
193 #ifndef OPENSSL_NO_SCTP
195 * Remember that a CCS has been received, so that an old key of
196 * SCTP-Auth can be deleted when a CCS is sent. Will be ignored if no
199 BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_AUTH_CCS_RCVD, 1, NULL);
203 return MSG_PROCESS_CONTINUE_READING;
205 ssl3_send_alert(s, SSL3_AL_FATAL, al);
206 ossl_statem_set_error(s);
207 return MSG_PROCESS_ERROR;
210 MSG_PROCESS_RETURN tls_process_finished(SSL *s, PACKET *pkt)
214 /* If this occurs, we have missed a message */
215 if (!s->s3->change_cipher_spec) {
216 al = SSL_AD_UNEXPECTED_MESSAGE;
217 SSLerr(SSL_F_TLS_PROCESS_FINISHED, SSL_R_GOT_A_FIN_BEFORE_A_CCS);
220 s->s3->change_cipher_spec = 0;
222 i = s->s3->tmp.peer_finish_md_len;
224 if ((unsigned long)i != PACKET_remaining(pkt)) {
225 al = SSL_AD_DECODE_ERROR;
226 SSLerr(SSL_F_TLS_PROCESS_FINISHED, SSL_R_BAD_DIGEST_LENGTH);
230 if (CRYPTO_memcmp(PACKET_data(pkt), s->s3->tmp.peer_finish_md, i) != 0) {
231 al = SSL_AD_DECRYPT_ERROR;
232 SSLerr(SSL_F_TLS_PROCESS_FINISHED, SSL_R_DIGEST_CHECK_FAILED);
237 * Copy the finished so we can use it for renegotiation checks
240 OPENSSL_assert(i <= EVP_MAX_MD_SIZE);
241 memcpy(s->s3->previous_client_finished, s->s3->tmp.peer_finish_md, i);
242 s->s3->previous_client_finished_len = i;
244 OPENSSL_assert(i <= EVP_MAX_MD_SIZE);
245 memcpy(s->s3->previous_server_finished, s->s3->tmp.peer_finish_md, i);
246 s->s3->previous_server_finished_len = i;
249 return MSG_PROCESS_FINISHED_READING;
251 ssl3_send_alert(s, SSL3_AL_FATAL, al);
252 ossl_statem_set_error(s);
253 return MSG_PROCESS_ERROR;
256 int tls_construct_change_cipher_spec(SSL *s)
260 p = (unsigned char *)s->init_buf->data;
268 unsigned long ssl3_output_cert_chain(SSL *s, CERT_PKEY *cpk)
271 unsigned long l = 3 + SSL_HM_HEADER_LENGTH(s);
273 if (!ssl_add_cert_chain(s, cpk, &l))
276 l -= 3 + SSL_HM_HEADER_LENGTH(s);
277 p = ssl_handshake_start(s);
281 if (!ssl_set_handshake_header(s, SSL3_MT_CERTIFICATE, l)) {
282 SSLerr(SSL_F_SSL3_OUTPUT_CERT_CHAIN, ERR_R_INTERNAL_ERROR);
285 return l + SSL_HM_HEADER_LENGTH(s);
288 WORK_STATE tls_finish_handshake(SSL *s, WORK_STATE wst)
290 void (*cb) (const SSL *ssl, int type, int val) = NULL;
292 #ifndef OPENSSL_NO_SCTP
293 if (SSL_IS_DTLS(s) && BIO_dgram_is_sctp(SSL_get_wbio(s))) {
295 ret = dtls_wait_for_dry(s);
296 if (ret != WORK_FINISHED_CONTINUE)
301 /* clean a few things up */
302 ssl3_cleanup_key_block(s);
304 if (!SSL_IS_DTLS(s)) {
306 * We don't do this in DTLS because we may still need the init_buf
307 * in case there are any unexpected retransmits
309 BUF_MEM_free(s->init_buf);
313 ssl_free_wbio_buffer(s);
317 if (!s->server || s->renegotiate == 2) {
318 /* skipped if we just sent a HelloRequest */
323 ssl_update_cache(s, SSL_SESS_CACHE_SERVER);
325 s->ctx->stats.sess_accept_good++;
326 s->handshake_func = ossl_statem_accept;
328 ssl_update_cache(s, SSL_SESS_CACHE_CLIENT);
330 s->ctx->stats.sess_hit++;
332 s->handshake_func = ossl_statem_connect;
333 s->ctx->stats.sess_connect_good++;
336 if (s->info_callback != NULL)
337 cb = s->info_callback;
338 else if (s->ctx->info_callback != NULL)
339 cb = s->ctx->info_callback;
342 cb(s, SSL_CB_HANDSHAKE_DONE, 1);
344 if (SSL_IS_DTLS(s)) {
345 /* done with handshaking */
346 s->d1->handshake_read_seq = 0;
347 s->d1->handshake_write_seq = 0;
348 s->d1->next_handshake_write_seq = 0;
349 dtls1_clear_received_buffer(s);
353 return WORK_FINISHED_STOP;
356 int tls_get_message_header(SSL *s, int *mt)
358 /* s->init_num < SSL3_HM_HEADER_LENGTH */
359 int skip_message, i, recvd_type, al;
363 p = (unsigned char *)s->init_buf->data;
366 while (s->init_num < SSL3_HM_HEADER_LENGTH) {
367 i = s->method->ssl_read_bytes(s, SSL3_RT_HANDSHAKE, &recvd_type,
369 SSL3_HM_HEADER_LENGTH - s->init_num,
372 s->rwstate = SSL_READING;
375 if (recvd_type == SSL3_RT_CHANGE_CIPHER_SPEC) {
377 * A ChangeCipherSpec must be a single byte and may not occur
378 * in the middle of a handshake message.
380 if (s->init_num != 0 || i != 1 || p[0] != SSL3_MT_CCS) {
381 al = SSL_AD_UNEXPECTED_MESSAGE;
382 SSLerr(SSL_F_TLS_GET_MESSAGE_HEADER,
383 SSL_R_BAD_CHANGE_CIPHER_SPEC);
386 s->s3->tmp.message_type = *mt = SSL3_MT_CHANGE_CIPHER_SPEC;
388 s->s3->tmp.message_size = i;
390 } else if (recvd_type != SSL3_RT_HANDSHAKE) {
391 al = SSL_AD_UNEXPECTED_MESSAGE;
392 SSLerr(SSL_F_TLS_GET_MESSAGE_HEADER, SSL_R_CCS_RECEIVED_EARLY);
400 if (p[0] == SSL3_MT_HELLO_REQUEST)
402 * The server may always send 'Hello Request' messages --
403 * we are doing a handshake anyway now, so ignore them if
404 * their format is correct. Does not count for 'Finished'
407 if (p[1] == 0 && p[2] == 0 && p[3] == 0) {
412 s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE,
413 p, SSL3_HM_HEADER_LENGTH, s,
414 s->msg_callback_arg);
416 } while (skip_message);
417 /* s->init_num == SSL3_HM_HEADER_LENGTH */
420 s->s3->tmp.message_type = *(p++);
422 if (RECORD_LAYER_is_sslv2_record(&s->rlayer)) {
424 * Only happens with SSLv3+ in an SSLv2 backward compatible
427 * Total message size is the remaining record bytes to read
428 * plus the SSL3_HM_HEADER_LENGTH bytes that we already read
430 l = RECORD_LAYER_get_rrec_length(&s->rlayer)
431 + SSL3_HM_HEADER_LENGTH;
432 if (l && !BUF_MEM_grow_clean(s->init_buf, (int)l)) {
433 SSLerr(SSL_F_TLS_GET_MESSAGE_HEADER, ERR_R_BUF_LIB);
436 s->s3->tmp.message_size = l;
438 s->init_msg = s->init_buf->data;
439 s->init_num = SSL3_HM_HEADER_LENGTH;
442 /* BUF_MEM_grow takes an 'int' parameter */
443 if (l > (INT_MAX - SSL3_HM_HEADER_LENGTH)) {
444 al = SSL_AD_ILLEGAL_PARAMETER;
445 SSLerr(SSL_F_TLS_GET_MESSAGE_HEADER, SSL_R_EXCESSIVE_MESSAGE_SIZE);
448 if (l && !BUF_MEM_grow_clean(s->init_buf,
449 (int)l + SSL3_HM_HEADER_LENGTH)) {
450 SSLerr(SSL_F_TLS_GET_MESSAGE_HEADER, ERR_R_BUF_LIB);
453 s->s3->tmp.message_size = l;
455 s->init_msg = s->init_buf->data + SSL3_HM_HEADER_LENGTH;
461 ssl3_send_alert(s, SSL3_AL_FATAL, al);
466 int tls_get_message_body(SSL *s, unsigned long *len)
472 if (s->s3->tmp.message_type == SSL3_MT_CHANGE_CIPHER_SPEC) {
473 /* We've already read everything in */
474 *len = (unsigned long)s->init_num;
479 n = s->s3->tmp.message_size - s->init_num;
481 i = s->method->ssl_read_bytes(s, SSL3_RT_HANDSHAKE, NULL,
482 &p[s->init_num], n, 0);
484 s->rwstate = SSL_READING;
492 #ifndef OPENSSL_NO_NEXTPROTONEG
494 * If receiving Finished, record MAC of prior handshake messages for
495 * Finished verification.
497 if (*s->init_buf->data == SSL3_MT_FINISHED)
501 /* Feed this message into MAC computation. */
502 if (RECORD_LAYER_is_sslv2_record(&s->rlayer)) {
503 if (!ssl3_finish_mac(s, (unsigned char *)s->init_buf->data,
505 SSLerr(SSL_F_TLS_GET_MESSAGE_BODY, ERR_R_EVP_LIB);
506 ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR);
511 s->msg_callback(0, SSL2_VERSION, 0, s->init_buf->data,
512 (size_t)s->init_num, s, s->msg_callback_arg);
514 if (!ssl3_finish_mac(s, (unsigned char *)s->init_buf->data,
515 s->init_num + SSL3_HM_HEADER_LENGTH)) {
516 SSLerr(SSL_F_TLS_GET_MESSAGE_BODY, ERR_R_EVP_LIB);
517 ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR);
522 s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE, s->init_buf->data,
523 (size_t)s->init_num + SSL3_HM_HEADER_LENGTH, s,
524 s->msg_callback_arg);
528 * init_num should never be negative...should probably be declared
531 if (s->init_num < 0) {
532 SSLerr(SSL_F_TLS_GET_MESSAGE_BODY, ERR_R_INTERNAL_ERROR);
533 ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR);
537 *len = (unsigned long)s->init_num;
541 int ssl_cert_type(const X509 *x, const EVP_PKEY *pk)
543 if (pk == NULL && (pk = X509_get0_pubkey(x)) == NULL)
546 switch (EVP_PKEY_id(pk)) {
550 return SSL_PKEY_RSA_ENC;
552 return SSL_PKEY_DSA_SIGN;
553 #ifndef OPENSSL_NO_EC
557 #ifndef OPENSSL_NO_GOST
558 case NID_id_GostR3410_2001:
559 return SSL_PKEY_GOST01;
560 case NID_id_GostR3410_2012_256:
561 return SSL_PKEY_GOST12_256;
562 case NID_id_GostR3410_2012_512:
563 return SSL_PKEY_GOST12_512;
568 int ssl_verify_alarm_type(long type)
573 case X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT:
574 case X509_V_ERR_UNABLE_TO_GET_CRL:
575 case X509_V_ERR_UNABLE_TO_GET_CRL_ISSUER:
576 al = SSL_AD_UNKNOWN_CA;
578 case X509_V_ERR_UNABLE_TO_DECRYPT_CERT_SIGNATURE:
579 case X509_V_ERR_UNABLE_TO_DECRYPT_CRL_SIGNATURE:
580 case X509_V_ERR_UNABLE_TO_DECODE_ISSUER_PUBLIC_KEY:
581 case X509_V_ERR_ERROR_IN_CERT_NOT_BEFORE_FIELD:
582 case X509_V_ERR_ERROR_IN_CERT_NOT_AFTER_FIELD:
583 case X509_V_ERR_ERROR_IN_CRL_LAST_UPDATE_FIELD:
584 case X509_V_ERR_ERROR_IN_CRL_NEXT_UPDATE_FIELD:
585 case X509_V_ERR_CERT_NOT_YET_VALID:
586 case X509_V_ERR_CRL_NOT_YET_VALID:
587 case X509_V_ERR_CERT_UNTRUSTED:
588 case X509_V_ERR_CERT_REJECTED:
589 case X509_V_ERR_HOSTNAME_MISMATCH:
590 case X509_V_ERR_EMAIL_MISMATCH:
591 case X509_V_ERR_IP_ADDRESS_MISMATCH:
592 case X509_V_ERR_DANE_NO_MATCH:
593 case X509_V_ERR_EE_KEY_TOO_SMALL:
594 case X509_V_ERR_CA_KEY_TOO_SMALL:
595 case X509_V_ERR_CA_MD_TOO_WEAK:
596 al = SSL_AD_BAD_CERTIFICATE;
598 case X509_V_ERR_CERT_SIGNATURE_FAILURE:
599 case X509_V_ERR_CRL_SIGNATURE_FAILURE:
600 al = SSL_AD_DECRYPT_ERROR;
602 case X509_V_ERR_CERT_HAS_EXPIRED:
603 case X509_V_ERR_CRL_HAS_EXPIRED:
604 al = SSL_AD_CERTIFICATE_EXPIRED;
606 case X509_V_ERR_CERT_REVOKED:
607 al = SSL_AD_CERTIFICATE_REVOKED;
609 case X509_V_ERR_UNSPECIFIED:
610 case X509_V_ERR_OUT_OF_MEM:
611 case X509_V_ERR_INVALID_CALL:
612 case X509_V_ERR_STORE_LOOKUP:
613 al = SSL_AD_INTERNAL_ERROR;
615 case X509_V_ERR_DEPTH_ZERO_SELF_SIGNED_CERT:
616 case X509_V_ERR_SELF_SIGNED_CERT_IN_CHAIN:
617 case X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT_LOCALLY:
618 case X509_V_ERR_UNABLE_TO_VERIFY_LEAF_SIGNATURE:
619 case X509_V_ERR_CERT_CHAIN_TOO_LONG:
620 case X509_V_ERR_PATH_LENGTH_EXCEEDED:
621 case X509_V_ERR_INVALID_CA:
622 al = SSL_AD_UNKNOWN_CA;
624 case X509_V_ERR_APPLICATION_VERIFICATION:
625 al = SSL_AD_HANDSHAKE_FAILURE;
627 case X509_V_ERR_INVALID_PURPOSE:
628 al = SSL_AD_UNSUPPORTED_CERTIFICATE;
631 al = SSL_AD_CERTIFICATE_UNKNOWN;
637 int ssl_allow_compression(SSL *s)
639 if (s->options & SSL_OP_NO_COMPRESSION)
641 return ssl_security(s, SSL_SECOP_COMPRESSION, 0, 0, NULL);
644 static int version_cmp(const SSL *s, int a, int b)
646 int dtls = SSL_IS_DTLS(s);
651 return a < b ? -1 : 1;
652 return DTLS_VERSION_LT(a, b) ? -1 : 1;
657 const SSL_METHOD *(*cmeth) (void);
658 const SSL_METHOD *(*smeth) (void);
661 #if TLS_MAX_VERSION != TLS1_2_VERSION
662 # error Code needs update for TLS_method() support beyond TLS1_2_VERSION.
665 static const version_info tls_version_table[] = {
666 #ifndef OPENSSL_NO_TLS1_2
667 {TLS1_2_VERSION, tlsv1_2_client_method, tlsv1_2_server_method},
669 {TLS1_2_VERSION, NULL, NULL},
671 #ifndef OPENSSL_NO_TLS1_1
672 {TLS1_1_VERSION, tlsv1_1_client_method, tlsv1_1_server_method},
674 {TLS1_1_VERSION, NULL, NULL},
676 #ifndef OPENSSL_NO_TLS1
677 {TLS1_VERSION, tlsv1_client_method, tlsv1_server_method},
679 {TLS1_VERSION, NULL, NULL},
681 #ifndef OPENSSL_NO_SSL3
682 {SSL3_VERSION, sslv3_client_method, sslv3_server_method},
684 {SSL3_VERSION, NULL, NULL},
689 #if DTLS_MAX_VERSION != DTLS1_2_VERSION
690 # error Code needs update for DTLS_method() support beyond DTLS1_2_VERSION.
693 static const version_info dtls_version_table[] = {
694 #ifndef OPENSSL_NO_DTLS1_2
695 {DTLS1_2_VERSION, dtlsv1_2_client_method, dtlsv1_2_server_method},
697 {DTLS1_2_VERSION, NULL, NULL},
699 #ifndef OPENSSL_NO_DTLS1
700 {DTLS1_VERSION, dtlsv1_client_method, dtlsv1_server_method},
701 {DTLS1_BAD_VER, dtls_bad_ver_client_method, NULL},
703 {DTLS1_VERSION, NULL, NULL},
704 {DTLS1_BAD_VER, NULL, NULL},
710 * ssl_method_error - Check whether an SSL_METHOD is enabled.
712 * @s: The SSL handle for the candidate method
713 * @method: the intended method.
715 * Returns 0 on success, or an SSL error reason on failure.
717 static int ssl_method_error(const SSL *s, const SSL_METHOD *method)
719 int version = method->version;
721 if ((s->min_proto_version != 0 &&
722 version_cmp(s, version, s->min_proto_version) < 0) ||
723 ssl_security(s, SSL_SECOP_VERSION, 0, version, NULL) == 0)
724 return SSL_R_VERSION_TOO_LOW;
726 if (s->max_proto_version != 0 &&
727 version_cmp(s, version, s->max_proto_version) > 0)
728 return SSL_R_VERSION_TOO_HIGH;
730 if ((s->options & method->mask) != 0)
731 return SSL_R_UNSUPPORTED_PROTOCOL;
732 if ((method->flags & SSL_METHOD_NO_SUITEB) != 0 && tls1_suiteb(s))
733 return SSL_R_AT_LEAST_TLS_1_2_NEEDED_IN_SUITEB_MODE;
734 else if ((method->flags & SSL_METHOD_NO_FIPS) != 0 && FIPS_mode())
735 return SSL_R_AT_LEAST_TLS_1_0_NEEDED_IN_FIPS_MODE;
741 * ssl_version_supported - Check that the specified `version` is supported by
744 * @s: The SSL handle for the candidate method
745 * @version: Protocol version to test against
747 * Returns 1 when supported, otherwise 0
749 int ssl_version_supported(const SSL *s, int version)
751 const version_info *vent;
752 const version_info *table;
754 switch (s->method->version) {
756 /* Version should match method version for non-ANY method */
757 return version_cmp(s, version, s->version) == 0;
758 case TLS_ANY_VERSION:
759 table = tls_version_table;
761 case DTLS_ANY_VERSION:
762 table = dtls_version_table;
767 vent->version != 0 && version_cmp(s, version, vent->version) <= 0;
769 if (vent->cmeth != NULL &&
770 version_cmp(s, version, vent->version) == 0 &&
771 ssl_method_error(s, vent->cmeth()) == 0) {
779 * ssl_check_version_downgrade - In response to RFC7507 SCSV version
780 * fallback indication from a client check whether we're using the highest
781 * supported protocol version.
783 * @s server SSL handle.
785 * Returns 1 when using the highest enabled version, 0 otherwise.
787 int ssl_check_version_downgrade(SSL *s)
789 const version_info *vent;
790 const version_info *table;
793 * Check that the current protocol is the highest enabled version
794 * (according to s->ctx->method, as version negotiation may have changed
797 if (s->version == s->ctx->method->version)
801 * Apparently we're using a version-flexible SSL_METHOD (not at its
802 * highest protocol version).
804 if (s->ctx->method->version == TLS_method()->version)
805 table = tls_version_table;
806 else if (s->ctx->method->version == DTLS_method()->version)
807 table = dtls_version_table;
809 /* Unexpected state; fail closed. */
813 for (vent = table; vent->version != 0; ++vent) {
814 if (vent->smeth != NULL && ssl_method_error(s, vent->smeth()) == 0)
815 return s->version == vent->version;
821 * ssl_set_version_bound - set an upper or lower bound on the supported (D)TLS
822 * protocols, provided the initial (D)TLS method is version-flexible. This
823 * function sanity-checks the proposed value and makes sure the method is
824 * version-flexible, then sets the limit if all is well.
826 * @method_version: The version of the current SSL_METHOD.
827 * @version: the intended limit.
828 * @bound: pointer to limit to be updated.
830 * Returns 1 on success, 0 on failure.
832 int ssl_set_version_bound(int method_version, int version, int *bound)
840 * Restrict TLS methods to TLS protocol versions.
841 * Restrict DTLS methods to DTLS protocol versions.
842 * Note, DTLS version numbers are decreasing, use comparison macros.
844 * Note that for both lower-bounds we use explicit versions, not
845 * (D)TLS_MIN_VERSION. This is because we don't want to break user
846 * configurations. If the MIN (supported) version ever rises, the user's
847 * "floor" remains valid even if no longer available. We don't expect the
848 * MAX ceiling to ever get lower, so making that variable makes sense.
850 switch (method_version) {
853 * XXX For fixed version methods, should we always fail and not set any
854 * bounds, always succeed and not set any bounds, or set the bounds and
855 * arrange to fail later if they are not met? At present fixed-version
856 * methods are not subject to controls that disable individual protocol
861 case TLS_ANY_VERSION:
862 if (version < SSL3_VERSION || version > TLS_MAX_VERSION)
866 case DTLS_ANY_VERSION:
867 if (DTLS_VERSION_GT(version, DTLS_MAX_VERSION) ||
868 DTLS_VERSION_LT(version, DTLS1_BAD_VER))
878 * ssl_choose_server_version - Choose server (D)TLS version. Called when the
879 * client HELLO is received to select the final server protocol version and
880 * the version specific method.
882 * @s: server SSL handle.
884 * Returns 0 on success or an SSL error reason number on failure.
886 int ssl_choose_server_version(SSL *s)
889 * With version-flexible methods we have an initial state with:
891 * s->method->version == (D)TLS_ANY_VERSION,
892 * s->version == (D)TLS_MAX_VERSION.
894 * So we detect version-flexible methods via the method version, not the
897 int server_version = s->method->version;
898 int client_version = s->client_version;
899 const version_info *vent;
900 const version_info *table;
903 switch (server_version) {
905 if (version_cmp(s, client_version, s->version) < 0)
906 return SSL_R_WRONG_SSL_VERSION;
908 * If this SSL handle is not from a version flexible method we don't
909 * (and never did) check min/max FIPS or Suite B constraints. Hope
910 * that's OK. It is up to the caller to not choose fixed protocol
911 * versions they don't want. If not, then easy to fix, just return
912 * ssl_method_error(s, s->method)
915 case TLS_ANY_VERSION:
916 table = tls_version_table;
918 case DTLS_ANY_VERSION:
919 table = dtls_version_table;
923 for (vent = table; vent->version != 0; ++vent) {
924 const SSL_METHOD *method;
926 if (vent->smeth == NULL ||
927 version_cmp(s, client_version, vent->version) < 0)
929 method = vent->smeth();
930 if (ssl_method_error(s, method) == 0) {
931 s->version = vent->version;
937 return disabled ? SSL_R_UNSUPPORTED_PROTOCOL : SSL_R_VERSION_TOO_LOW;
941 * ssl_choose_client_version - Choose client (D)TLS version. Called when the
942 * server HELLO is received to select the final client protocol version and
943 * the version specific method.
945 * @s: client SSL handle.
946 * @version: The proposed version from the server's HELLO.
948 * Returns 0 on success or an SSL error reason number on failure.
950 int ssl_choose_client_version(SSL *s, int version)
952 const version_info *vent;
953 const version_info *table;
955 switch (s->method->version) {
957 if (version != s->version)
958 return SSL_R_WRONG_SSL_VERSION;
960 * If this SSL handle is not from a version flexible method we don't
961 * (and never did) check min/max, FIPS or Suite B constraints. Hope
962 * that's OK. It is up to the caller to not choose fixed protocol
963 * versions they don't want. If not, then easy to fix, just return
964 * ssl_method_error(s, s->method)
967 case TLS_ANY_VERSION:
968 table = tls_version_table;
970 case DTLS_ANY_VERSION:
971 table = dtls_version_table;
975 for (vent = table; vent->version != 0; ++vent) {
976 const SSL_METHOD *method;
979 if (version != vent->version)
981 if (vent->cmeth == NULL)
983 method = vent->cmeth();
984 err = ssl_method_error(s, method);
988 s->version = version;
992 return SSL_R_UNSUPPORTED_PROTOCOL;
996 * ssl_get_client_min_max_version - get minimum and maximum client version
997 * @s: The SSL connection
998 * @min_version: The minimum supported version
999 * @max_version: The maximum supported version
1001 * Work out what version we should be using for the initial ClientHello if the
1002 * version is initially (D)TLS_ANY_VERSION. We apply any explicit SSL_OP_NO_xxx
1003 * options, the MinProtocol and MaxProtocol configuration commands, any Suite B
1004 * or FIPS_mode() constraints and any floor imposed by the security level here,
1005 * so we don't advertise the wrong protocol version to only reject the outcome later.
1007 * Computing the right floor matters. If, e.g., TLS 1.0 and 1.2 are enabled,
1008 * TLS 1.1 is disabled, but the security level, Suite-B and/or MinProtocol
1009 * only allow TLS 1.2, we want to advertise TLS1.2, *not* TLS1.
1011 * Returns 0 on success or an SSL error reason number on failure. On failure
1012 * min_version and max_version will also be set to 0.
1014 int ssl_get_client_min_max_version(const SSL *s, int *min_version,
1019 const SSL_METHOD *single = NULL;
1020 const SSL_METHOD *method;
1021 const version_info *table;
1022 const version_info *vent;
1024 switch (s->method->version) {
1027 * If this SSL handle is not from a version flexible method we don't
1028 * (and never did) check min/max FIPS or Suite B constraints. Hope
1029 * that's OK. It is up to the caller to not choose fixed protocol
1030 * versions they don't want. If not, then easy to fix, just return
1031 * ssl_method_error(s, s->method)
1033 *min_version = *max_version = s->version;
1035 case TLS_ANY_VERSION:
1036 table = tls_version_table;
1038 case DTLS_ANY_VERSION:
1039 table = dtls_version_table;
1044 * SSL_OP_NO_X disables all protocols above X *if* there are some protocols
1045 * below X enabled. This is required in order to maintain the "version
1046 * capability" vector contiguous. Any versions with a NULL client method
1047 * (protocol version client is disabled at compile-time) is also a "hole".
1049 * Our initial state is hole == 1, version == 0. That is, versions above
1050 * the first version in the method table are disabled (a "hole" above
1051 * the valid protocol entries) and we don't have a selected version yet.
1053 * Whenever "hole == 1", and we hit an enabled method, its version becomes
1054 * the selected version, and the method becomes a candidate "single"
1055 * method. We're no longer in a hole, so "hole" becomes 0.
1057 * If "hole == 0" and we hit an enabled method, then "single" is cleared,
1058 * as we support a contiguous range of at least two methods. If we hit
1059 * a disabled method, then hole becomes true again, but nothing else
1060 * changes yet, because all the remaining methods may be disabled too.
1061 * If we again hit an enabled method after the new hole, it becomes
1062 * selected, as we start from scratch.
1064 *min_version = version = 0;
1066 for (vent = table; vent->version != 0; ++vent) {
1068 * A table entry with a NULL client method is still a hole in the
1069 * "version capability" vector.
1071 if (vent->cmeth == NULL) {
1075 method = vent->cmeth();
1076 if (ssl_method_error(s, method) != 0) {
1080 *min_version = method->version;
1082 version = (single = method)->version;
1083 *min_version = version;
1088 *max_version = version;
1090 /* Fail if everything is disabled */
1092 return SSL_R_NO_PROTOCOLS_AVAILABLE;
1098 * ssl_set_client_hello_version - Work out what version we should be using for
1099 * the initial ClientHello.
1101 * @s: client SSL handle.
1103 * Returns 0 on success or an SSL error reason number on failure.
1105 int ssl_set_client_hello_version(SSL *s)
1107 int ver_min, ver_max, ret;
1109 ret = ssl_get_client_min_max_version(s, &ver_min, &ver_max);
1114 s->client_version = s->version = ver_max;