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_setup_handshake(SSL *s)
77 if (!ssl3_init_finished_mac(s))
81 if (SSL_IS_FIRST_HANDSHAKE(s)) {
82 s->ctx->stats.sess_accept++;
83 } else if (!s->s3->send_connection_binding &&
85 SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION)) {
87 * Server attempting to renegotiate with client that doesn't
88 * support secure renegotiation.
90 SSLerr(SSL_F_TLS_SETUP_HANDSHAKE,
91 SSL_R_UNSAFE_LEGACY_RENEGOTIATION_DISABLED);
92 ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_HANDSHAKE_FAILURE);
95 s->ctx->stats.sess_accept_renegotiate++;
97 s->s3->tmp.cert_request = 0;
100 if (SSL_IS_FIRST_HANDSHAKE(s))
101 s->ctx->stats.sess_connect++;
103 s->ctx->stats.sess_connect_renegotiate++;
105 /* mark client_random uninitialized */
106 memset(s->s3->client_random, 0, sizeof(s->s3->client_random));
109 s->s3->tmp.cert_req = 0;
112 s->statem.use_timer = 1;
119 * Size of the to-be-signed TLS13 data, without the hash size itself:
120 * 64 bytes of value 32, 33 context bytes, 1 byte separator
122 #define TLS13_TBS_START_SIZE 64
123 #define TLS13_TBS_PREAMBLE_SIZE (TLS13_TBS_START_SIZE + 33 + 1)
125 static int get_cert_verify_tbs_data(SSL *s, unsigned char *tls13tbs,
126 void **hdata, size_t *hdatalen)
128 static const char *servercontext = "TLS 1.3, server CertificateVerify";
129 static const char *clientcontext = "TLS 1.3, client CertificateVerify";
131 if (SSL_IS_TLS13(s)) {
134 /* Set the first 64 bytes of to-be-signed data to octet 32 */
135 memset(tls13tbs, 32, TLS13_TBS_START_SIZE);
136 /* This copies the 33 bytes of context plus the 0 separator byte */
137 if (s->statem.hand_state == TLS_ST_CR_CERT_VRFY
138 || s->statem.hand_state == TLS_ST_SW_CERT_VRFY)
139 strcpy((char *)tls13tbs + TLS13_TBS_START_SIZE, servercontext);
141 strcpy((char *)tls13tbs + TLS13_TBS_START_SIZE, clientcontext);
144 * If we're currently reading then we need to use the saved handshake
145 * hash value. We can't use the current handshake hash state because
146 * that includes the CertVerify itself.
148 if (s->statem.hand_state == TLS_ST_CR_CERT_VRFY
149 || s->statem.hand_state == TLS_ST_SR_CERT_VRFY) {
150 memcpy(tls13tbs + TLS13_TBS_PREAMBLE_SIZE, s->cert_verify_hash,
151 s->cert_verify_hash_len);
152 hashlen = s->cert_verify_hash_len;
153 } else if (!ssl_handshake_hash(s, tls13tbs + TLS13_TBS_PREAMBLE_SIZE,
154 EVP_MAX_MD_SIZE, &hashlen)) {
159 *hdatalen = TLS13_TBS_PREAMBLE_SIZE + hashlen;
163 retlen = BIO_get_mem_data(s->s3->handshake_buffer, hdata);
172 int tls_construct_cert_verify(SSL *s, WPACKET *pkt)
176 EVP_MD_CTX *mctx = NULL;
177 EVP_PKEY_CTX *pctx = NULL;
178 size_t hdatalen = 0, siglen = 0;
180 unsigned char *sig = NULL;
181 unsigned char tls13tbs[TLS13_TBS_PREAMBLE_SIZE + EVP_MAX_MD_SIZE];
182 int pktype, ispss = 0;
185 /* Only happens in TLSv1.3 */
187 * TODO(TLS1.3): This needs to change. We should not get this from the
188 * cipher. However, for now, we have not done the work to separate the
189 * certificate type from the ciphersuite
191 pkey = ssl_get_sign_pkey(s, s->s3->tmp.new_cipher, &md);
195 md = s->s3->tmp.md[s->cert->key - s->cert->pkeys];
196 pkey = s->cert->key->privatekey;
198 pktype = EVP_PKEY_id(pkey);
200 mctx = EVP_MD_CTX_new();
202 SSLerr(SSL_F_TLS_CONSTRUCT_CERT_VERIFY, ERR_R_MALLOC_FAILURE);
206 /* Get the data to be signed */
207 if (!get_cert_verify_tbs_data(s, tls13tbs, &hdata, &hdatalen)) {
208 SSLerr(SSL_F_TLS_CONSTRUCT_CERT_VERIFY, ERR_R_INTERNAL_ERROR);
212 if (SSL_USE_SIGALGS(s) && !tls12_get_sigandhash(s, pkt, pkey, md, &ispss)) {
213 SSLerr(SSL_F_TLS_CONSTRUCT_CERT_VERIFY, ERR_R_INTERNAL_ERROR);
217 fprintf(stderr, "Using client alg %s\n", EVP_MD_name(md));
219 siglen = EVP_PKEY_size(pkey);
220 sig = OPENSSL_malloc(siglen);
222 SSLerr(SSL_F_TLS_CONSTRUCT_CERT_VERIFY, ERR_R_MALLOC_FAILURE);
226 if (EVP_DigestSignInit(mctx, &pctx, md, NULL, pkey) <= 0
227 || EVP_DigestSignUpdate(mctx, hdata, hdatalen) <= 0) {
228 SSLerr(SSL_F_TLS_CONSTRUCT_CERT_VERIFY, ERR_R_EVP_LIB);
233 if (EVP_PKEY_CTX_set_rsa_padding(pctx, RSA_PKCS1_PSS_PADDING) <= 0
234 || EVP_PKEY_CTX_set_rsa_pss_saltlen(pctx,
235 RSA_PSS_SALTLEN_DIGEST) <= 0) {
236 SSLerr(SSL_F_TLS_CONSTRUCT_CERT_VERIFY, ERR_R_EVP_LIB);
239 } else if (s->version == SSL3_VERSION) {
240 if (!EVP_MD_CTX_ctrl(mctx, EVP_CTRL_SSL3_MASTER_SECRET,
241 (int)s->session->master_key_length,
242 s->session->master_key)) {
243 SSLerr(SSL_F_TLS_CONSTRUCT_CERT_VERIFY, ERR_R_EVP_LIB);
248 if (EVP_DigestSignFinal(mctx, sig, &siglen) <= 0) {
249 SSLerr(SSL_F_TLS_CONSTRUCT_CERT_VERIFY, ERR_R_EVP_LIB);
253 #ifndef OPENSSL_NO_GOST
255 if (pktype == NID_id_GostR3410_2001
256 || pktype == NID_id_GostR3410_2012_256
257 || pktype == NID_id_GostR3410_2012_512)
258 BUF_reverse(sig, NULL, siglen);
262 if (!WPACKET_sub_memcpy_u16(pkt, sig, siglen)) {
263 SSLerr(SSL_F_TLS_CONSTRUCT_CERT_VERIFY, ERR_R_INTERNAL_ERROR);
267 /* Digest cached records and discard handshake buffer */
268 if (!ssl3_digest_cached_records(s, 0))
272 EVP_MD_CTX_free(mctx);
276 EVP_MD_CTX_free(mctx);
277 ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR);
281 MSG_PROCESS_RETURN tls_process_cert_verify(SSL *s, PACKET *pkt)
283 EVP_PKEY *pkey = NULL;
284 const unsigned char *data;
285 #ifndef OPENSSL_NO_GOST
286 unsigned char *gost_data = NULL;
288 int al = SSL_AD_INTERNAL_ERROR, ret = MSG_PROCESS_ERROR;
289 int type = 0, j, pktype;
292 const EVP_MD *md = NULL;
295 unsigned char tls13tbs[TLS13_TBS_PREAMBLE_SIZE + EVP_MAX_MD_SIZE];
296 EVP_MD_CTX *mctx = EVP_MD_CTX_new();
297 EVP_PKEY_CTX *pctx = NULL;
300 SSLerr(SSL_F_TLS_PROCESS_CERT_VERIFY, ERR_R_MALLOC_FAILURE);
304 peer = s->session->peer;
305 pkey = X509_get0_pubkey(peer);
306 pktype = EVP_PKEY_id(pkey);
307 type = X509_certificate_type(peer, pkey);
309 if (!(type & EVP_PKT_SIGN)) {
310 SSLerr(SSL_F_TLS_PROCESS_CERT_VERIFY,
311 SSL_R_SIGNATURE_FOR_NON_SIGNING_CERTIFICATE);
312 al = SSL_AD_ILLEGAL_PARAMETER;
316 /* Check for broken implementations of GOST ciphersuites */
318 * If key is GOST and n is exactly 64, it is bare signature without
319 * length field (CryptoPro implementations at least till CSP 4.0)
321 #ifndef OPENSSL_NO_GOST
322 if (PACKET_remaining(pkt) == 64
323 && EVP_PKEY_id(pkey) == NID_id_GostR3410_2001) {
328 if (SSL_USE_SIGALGS(s)) {
332 if (!PACKET_get_net_2(pkt, &sigalg)) {
333 al = SSL_AD_DECODE_ERROR;
336 rv = tls12_check_peer_sigalg(s, sigalg, pkey);
339 } else if (rv == 0) {
340 al = SSL_AD_DECODE_ERROR;
343 md = s->s3->tmp.peer_md;
345 fprintf(stderr, "USING TLSv1.2 HASH %s\n", EVP_MD_name(md));
348 /* Use default digest for this key type */
349 int idx = ssl_cert_type(NULL, pkey);
351 md = s->s3->tmp.md[idx];
353 al = SSL_AD_INTERNAL_ERROR;
358 if (!PACKET_get_net_2(pkt, &len)) {
359 SSLerr(SSL_F_TLS_PROCESS_CERT_VERIFY, SSL_R_LENGTH_MISMATCH);
360 al = SSL_AD_DECODE_ERROR;
364 j = EVP_PKEY_size(pkey);
365 if (((int)len > j) || ((int)PACKET_remaining(pkt) > j)
366 || (PACKET_remaining(pkt) == 0)) {
367 SSLerr(SSL_F_TLS_PROCESS_CERT_VERIFY, SSL_R_WRONG_SIGNATURE_SIZE);
368 al = SSL_AD_DECODE_ERROR;
371 if (!PACKET_get_bytes(pkt, &data, len)) {
372 SSLerr(SSL_F_TLS_PROCESS_CERT_VERIFY, SSL_R_LENGTH_MISMATCH);
373 al = SSL_AD_DECODE_ERROR;
377 if (!get_cert_verify_tbs_data(s, tls13tbs, &hdata, &hdatalen)) {
378 SSLerr(SSL_F_TLS_PROCESS_CERT_VERIFY, ERR_R_INTERNAL_ERROR);
383 fprintf(stderr, "Using client verify alg %s\n", EVP_MD_name(md));
385 if (EVP_DigestVerifyInit(mctx, &pctx, md, NULL, pkey) <= 0
386 || EVP_DigestVerifyUpdate(mctx, hdata, hdatalen) <= 0) {
387 SSLerr(SSL_F_TLS_PROCESS_CERT_VERIFY, ERR_R_EVP_LIB);
390 #ifndef OPENSSL_NO_GOST
392 if (pktype == NID_id_GostR3410_2001
393 || pktype == NID_id_GostR3410_2012_256
394 || pktype == NID_id_GostR3410_2012_512) {
395 if ((gost_data = OPENSSL_malloc(len)) == NULL) {
396 SSLerr(SSL_F_TLS_PROCESS_CERT_VERIFY, ERR_R_MALLOC_FAILURE);
399 BUF_reverse(gost_data, data, len);
405 if (SSL_USE_PSS(s)) {
406 if (EVP_PKEY_CTX_set_rsa_padding(pctx, RSA_PKCS1_PSS_PADDING) <= 0
407 || EVP_PKEY_CTX_set_rsa_pss_saltlen(pctx,
408 RSA_PSS_SALTLEN_DIGEST) <= 0) {
409 SSLerr(SSL_F_TLS_PROCESS_CERT_VERIFY, ERR_R_EVP_LIB);
412 } else if (s->version == SSL3_VERSION
413 && !EVP_MD_CTX_ctrl(mctx, EVP_CTRL_SSL3_MASTER_SECRET,
414 (int)s->session->master_key_length,
415 s->session->master_key)) {
416 SSLerr(SSL_F_TLS_PROCESS_CERT_VERIFY, ERR_R_EVP_LIB);
420 if (EVP_DigestVerifyFinal(mctx, data, len) <= 0) {
421 al = SSL_AD_DECRYPT_ERROR;
422 SSLerr(SSL_F_TLS_PROCESS_CERT_VERIFY, SSL_R_BAD_SIGNATURE);
427 ret = MSG_PROCESS_CONTINUE_READING;
429 ret = MSG_PROCESS_CONTINUE_PROCESSING;
432 ssl3_send_alert(s, SSL3_AL_FATAL, al);
433 ossl_statem_set_error(s);
435 BIO_free(s->s3->handshake_buffer);
436 s->s3->handshake_buffer = NULL;
437 EVP_MD_CTX_free(mctx);
438 #ifndef OPENSSL_NO_GOST
439 OPENSSL_free(gost_data);
444 int tls_construct_finished(SSL *s, WPACKET *pkt)
446 size_t finish_md_len;
451 sender = s->method->ssl3_enc->server_finished_label;
452 slen = s->method->ssl3_enc->server_finished_label_len;
454 sender = s->method->ssl3_enc->client_finished_label;
455 slen = s->method->ssl3_enc->client_finished_label_len;
458 finish_md_len = s->method->ssl3_enc->final_finish_mac(s,
460 s->s3->tmp.finish_md);
461 if (finish_md_len == 0) {
462 SSLerr(SSL_F_TLS_CONSTRUCT_FINISHED, ERR_R_INTERNAL_ERROR);
466 s->s3->tmp.finish_md_len = finish_md_len;
468 if (!WPACKET_memcpy(pkt, s->s3->tmp.finish_md, finish_md_len)) {
469 SSLerr(SSL_F_TLS_CONSTRUCT_FINISHED, ERR_R_INTERNAL_ERROR);
473 /* Log the master secret, if logging is enabled. */
474 if (!ssl_log_master_secret(s, s->s3->client_random, SSL3_RANDOM_SIZE,
475 s->session->master_key,
476 s->session->master_key_length))
480 * Copy the finished so we can use it for renegotiation checks
483 OPENSSL_assert(finish_md_len <= EVP_MAX_MD_SIZE);
484 memcpy(s->s3->previous_client_finished, s->s3->tmp.finish_md,
486 s->s3->previous_client_finished_len = finish_md_len;
488 OPENSSL_assert(finish_md_len <= EVP_MAX_MD_SIZE);
489 memcpy(s->s3->previous_server_finished, s->s3->tmp.finish_md,
491 s->s3->previous_server_finished_len = finish_md_len;
496 ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR);
500 #ifndef OPENSSL_NO_NEXTPROTONEG
502 * ssl3_take_mac calculates the Finished MAC for the handshakes messages seen
505 static void ssl3_take_mac(SSL *s)
510 * If no new cipher setup return immediately: other functions will set
511 * the appropriate error.
513 if (s->s3->tmp.new_cipher == NULL)
516 sender = s->method->ssl3_enc->server_finished_label;
517 slen = s->method->ssl3_enc->server_finished_label_len;
519 sender = s->method->ssl3_enc->client_finished_label;
520 slen = s->method->ssl3_enc->client_finished_label_len;
523 s->s3->tmp.peer_finish_md_len = s->method->ssl3_enc->final_finish_mac(s,
526 s->s3->tmp.peer_finish_md);
530 MSG_PROCESS_RETURN tls_process_change_cipher_spec(SSL *s, PACKET *pkt)
535 remain = PACKET_remaining(pkt);
537 * 'Change Cipher Spec' is just a single byte, which should already have
538 * been consumed by ssl_get_message() so there should be no bytes left,
539 * unless we're using DTLS1_BAD_VER, which has an extra 2 bytes
541 if (SSL_IS_DTLS(s)) {
542 if ((s->version == DTLS1_BAD_VER
543 && remain != DTLS1_CCS_HEADER_LENGTH + 1)
544 || (s->version != DTLS1_BAD_VER
545 && remain != DTLS1_CCS_HEADER_LENGTH - 1)) {
546 al = SSL_AD_ILLEGAL_PARAMETER;
547 SSLerr(SSL_F_TLS_PROCESS_CHANGE_CIPHER_SPEC,
548 SSL_R_BAD_CHANGE_CIPHER_SPEC);
553 al = SSL_AD_ILLEGAL_PARAMETER;
554 SSLerr(SSL_F_TLS_PROCESS_CHANGE_CIPHER_SPEC,
555 SSL_R_BAD_CHANGE_CIPHER_SPEC);
560 /* Check we have a cipher to change to */
561 if (s->s3->tmp.new_cipher == NULL) {
562 al = SSL_AD_UNEXPECTED_MESSAGE;
563 SSLerr(SSL_F_TLS_PROCESS_CHANGE_CIPHER_SPEC, SSL_R_CCS_RECEIVED_EARLY);
567 s->s3->change_cipher_spec = 1;
568 if (!ssl3_do_change_cipher_spec(s)) {
569 al = SSL_AD_INTERNAL_ERROR;
570 SSLerr(SSL_F_TLS_PROCESS_CHANGE_CIPHER_SPEC, ERR_R_INTERNAL_ERROR);
574 if (SSL_IS_DTLS(s)) {
575 dtls1_reset_seq_numbers(s, SSL3_CC_READ);
577 if (s->version == DTLS1_BAD_VER)
578 s->d1->handshake_read_seq++;
580 #ifndef OPENSSL_NO_SCTP
582 * Remember that a CCS has been received, so that an old key of
583 * SCTP-Auth can be deleted when a CCS is sent. Will be ignored if no
586 BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_AUTH_CCS_RCVD, 1, NULL);
590 return MSG_PROCESS_CONTINUE_READING;
592 ssl3_send_alert(s, SSL3_AL_FATAL, al);
593 ossl_statem_set_error(s);
594 return MSG_PROCESS_ERROR;
597 MSG_PROCESS_RETURN tls_process_finished(SSL *s, PACKET *pkt)
599 int al = SSL_AD_INTERNAL_ERROR;
602 /* If this occurs, we have missed a message */
603 if (!SSL_IS_TLS13(s) && !s->s3->change_cipher_spec) {
604 al = SSL_AD_UNEXPECTED_MESSAGE;
605 SSLerr(SSL_F_TLS_PROCESS_FINISHED, SSL_R_GOT_A_FIN_BEFORE_A_CCS);
608 s->s3->change_cipher_spec = 0;
610 md_len = s->s3->tmp.peer_finish_md_len;
612 if (md_len != PACKET_remaining(pkt)) {
613 al = SSL_AD_DECODE_ERROR;
614 SSLerr(SSL_F_TLS_PROCESS_FINISHED, SSL_R_BAD_DIGEST_LENGTH);
618 if (CRYPTO_memcmp(PACKET_data(pkt), s->s3->tmp.peer_finish_md,
620 al = SSL_AD_DECRYPT_ERROR;
621 SSLerr(SSL_F_TLS_PROCESS_FINISHED, SSL_R_DIGEST_CHECK_FAILED);
626 * Copy the finished so we can use it for renegotiation checks
629 OPENSSL_assert(md_len <= EVP_MAX_MD_SIZE);
630 memcpy(s->s3->previous_client_finished, s->s3->tmp.peer_finish_md,
632 s->s3->previous_client_finished_len = md_len;
634 OPENSSL_assert(md_len <= EVP_MAX_MD_SIZE);
635 memcpy(s->s3->previous_server_finished, s->s3->tmp.peer_finish_md,
637 s->s3->previous_server_finished_len = md_len;
641 * In TLS1.3 we also have to change cipher state and do any final processing
642 * of the initial server flight (if we are a client)
644 if (SSL_IS_TLS13(s)) {
646 if (!s->method->ssl3_enc->change_cipher_state(s,
647 SSL3_CC_APPLICATION | SSL3_CHANGE_CIPHER_SERVER_READ)) {
648 SSLerr(SSL_F_TLS_PROCESS_FINISHED, SSL_R_CANNOT_CHANGE_CIPHER);
652 if (!s->method->ssl3_enc->generate_master_secret(s,
653 s->master_secret, s->handshake_secret, 0,
654 &s->session->master_key_length)) {
655 SSLerr(SSL_F_TLS_PROCESS_FINISHED, SSL_R_CANNOT_CHANGE_CIPHER);
658 if (!s->method->ssl3_enc->change_cipher_state(s,
659 SSL3_CC_APPLICATION | SSL3_CHANGE_CIPHER_CLIENT_READ)) {
660 SSLerr(SSL_F_TLS_PROCESS_FINISHED, SSL_R_CANNOT_CHANGE_CIPHER);
663 if (!tls_process_initial_server_flight(s, &al))
668 return MSG_PROCESS_FINISHED_READING;
670 ssl3_send_alert(s, SSL3_AL_FATAL, al);
671 ossl_statem_set_error(s);
672 return MSG_PROCESS_ERROR;
675 int tls_construct_change_cipher_spec(SSL *s, WPACKET *pkt)
677 if (!WPACKET_put_bytes_u8(pkt, SSL3_MT_CCS)) {
678 SSLerr(SSL_F_TLS_CONSTRUCT_CHANGE_CIPHER_SPEC, ERR_R_INTERNAL_ERROR);
679 ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR);
686 /* Add a certificate to the WPACKET */
687 static int ssl_add_cert_to_wpacket(SSL *s, WPACKET *pkt, X509 *x, int chain,
691 unsigned char *outbytes;
693 len = i2d_X509(x, NULL);
695 SSLerr(SSL_F_SSL_ADD_CERT_TO_WPACKET, ERR_R_BUF_LIB);
696 *al = SSL_AD_INTERNAL_ERROR;
699 if (!WPACKET_sub_allocate_bytes_u24(pkt, len, &outbytes)
700 || i2d_X509(x, &outbytes) != len) {
701 SSLerr(SSL_F_SSL_ADD_CERT_TO_WPACKET, ERR_R_INTERNAL_ERROR);
702 *al = SSL_AD_INTERNAL_ERROR;
707 && !tls_construct_extensions(s, pkt, EXT_TLS1_3_CERTIFICATE, x,
714 /* Add certificate chain to provided WPACKET */
715 static int ssl_add_cert_chain(SSL *s, WPACKET *pkt, CERT_PKEY *cpk, int *al)
719 STACK_OF(X509) *extra_certs;
720 STACK_OF(X509) *chain = NULL;
721 X509_STORE *chain_store;
722 int tmpal = SSL_AD_INTERNAL_ERROR;
724 if (cpk == NULL || cpk->x509 == NULL)
730 * If we have a certificate specific chain use it, else use parent ctx.
732 if (cpk->chain != NULL)
733 extra_certs = cpk->chain;
735 extra_certs = s->ctx->extra_certs;
737 if ((s->mode & SSL_MODE_NO_AUTO_CHAIN) || extra_certs)
739 else if (s->cert->chain_store)
740 chain_store = s->cert->chain_store;
742 chain_store = s->ctx->cert_store;
744 if (chain_store != NULL) {
745 X509_STORE_CTX *xs_ctx = X509_STORE_CTX_new();
747 if (xs_ctx == NULL) {
748 SSLerr(SSL_F_SSL_ADD_CERT_CHAIN, ERR_R_MALLOC_FAILURE);
751 if (!X509_STORE_CTX_init(xs_ctx, chain_store, x, NULL)) {
752 X509_STORE_CTX_free(xs_ctx);
753 SSLerr(SSL_F_SSL_ADD_CERT_CHAIN, ERR_R_X509_LIB);
757 * It is valid for the chain not to be complete (because normally we
758 * don't include the root cert in the chain). Therefore we deliberately
759 * ignore the error return from this call. We're not actually verifying
760 * the cert - we're just building as much of the chain as we can
762 (void)X509_verify_cert(xs_ctx);
763 /* Don't leave errors in the queue */
765 chain = X509_STORE_CTX_get0_chain(xs_ctx);
766 i = ssl_security_cert_chain(s, chain, NULL, 0);
769 /* Dummy error calls so mkerr generates them */
770 SSLerr(SSL_F_SSL_ADD_CERT_CHAIN, SSL_R_EE_KEY_TOO_SMALL);
771 SSLerr(SSL_F_SSL_ADD_CERT_CHAIN, SSL_R_CA_KEY_TOO_SMALL);
772 SSLerr(SSL_F_SSL_ADD_CERT_CHAIN, SSL_R_CA_MD_TOO_WEAK);
774 X509_STORE_CTX_free(xs_ctx);
775 SSLerr(SSL_F_SSL_ADD_CERT_CHAIN, i);
778 chain_count = sk_X509_num(chain);
779 for (i = 0; i < chain_count; i++) {
780 x = sk_X509_value(chain, i);
782 if (!ssl_add_cert_to_wpacket(s, pkt, x, i, &tmpal)) {
783 X509_STORE_CTX_free(xs_ctx);
787 X509_STORE_CTX_free(xs_ctx);
789 i = ssl_security_cert_chain(s, extra_certs, x, 0);
791 SSLerr(SSL_F_SSL_ADD_CERT_CHAIN, i);
794 if (!ssl_add_cert_to_wpacket(s, pkt, x, 0, &tmpal))
796 for (i = 0; i < sk_X509_num(extra_certs); i++) {
797 x = sk_X509_value(extra_certs, i);
798 if (!ssl_add_cert_to_wpacket(s, pkt, x, i + 1, &tmpal))
809 unsigned long ssl3_output_cert_chain(SSL *s, WPACKET *pkt, CERT_PKEY *cpk,
812 int tmpal = SSL_AD_INTERNAL_ERROR;
814 if (!WPACKET_start_sub_packet_u24(pkt)
815 || !ssl_add_cert_chain(s, pkt, cpk, &tmpal)
816 || !WPACKET_close(pkt)) {
817 SSLerr(SSL_F_SSL3_OUTPUT_CERT_CHAIN, ERR_R_INTERNAL_ERROR);
825 * Tidy up after the end of a handshake. In the case of SCTP this may result
826 * in NBIO events. If |clearbufs| is set then init_buf and the wbio buffer is
829 WORK_STATE tls_finish_handshake(SSL *s, WORK_STATE wst, int clearbufs)
831 void (*cb) (const SSL *ssl, int type, int val) = NULL;
833 #ifndef OPENSSL_NO_SCTP
834 if (SSL_IS_DTLS(s) && BIO_dgram_is_sctp(SSL_get_wbio(s))) {
836 ret = dtls_wait_for_dry(s);
837 if (ret != WORK_FINISHED_CONTINUE)
843 if (!SSL_IS_DTLS(s)) {
845 * We don't do this in DTLS because we may still need the init_buf
846 * in case there are any unexpected retransmits
848 BUF_MEM_free(s->init_buf);
851 ssl_free_wbio_buffer(s);
855 if (s->statem.cleanuphand) {
856 /* skipped if we just sent a HelloRequest */
859 s->statem.cleanuphand = 0;
861 ssl3_cleanup_key_block(s);
864 ssl_update_cache(s, SSL_SESS_CACHE_SERVER);
866 s->ctx->stats.sess_accept_good++;
867 s->handshake_func = ossl_statem_accept;
869 ssl_update_cache(s, SSL_SESS_CACHE_CLIENT);
871 s->ctx->stats.sess_hit++;
873 s->handshake_func = ossl_statem_connect;
874 s->ctx->stats.sess_connect_good++;
877 if (s->info_callback != NULL)
878 cb = s->info_callback;
879 else if (s->ctx->info_callback != NULL)
880 cb = s->ctx->info_callback;
883 cb(s, SSL_CB_HANDSHAKE_DONE, 1);
885 if (SSL_IS_DTLS(s)) {
886 /* done with handshaking */
887 s->d1->handshake_read_seq = 0;
888 s->d1->handshake_write_seq = 0;
889 s->d1->next_handshake_write_seq = 0;
890 dtls1_clear_received_buffer(s);
895 * If we've not cleared the buffers its because we've got more work to do,
899 return WORK_FINISHED_CONTINUE;
901 return WORK_FINISHED_STOP;
904 int tls_get_message_header(SSL *s, int *mt)
906 /* s->init_num < SSL3_HM_HEADER_LENGTH */
907 int skip_message, i, recvd_type, al;
911 p = (unsigned char *)s->init_buf->data;
914 while (s->init_num < SSL3_HM_HEADER_LENGTH) {
915 i = s->method->ssl_read_bytes(s, SSL3_RT_HANDSHAKE, &recvd_type,
917 SSL3_HM_HEADER_LENGTH - s->init_num,
920 s->rwstate = SSL_READING;
923 if (recvd_type == SSL3_RT_CHANGE_CIPHER_SPEC) {
925 * A ChangeCipherSpec must be a single byte and may not occur
926 * in the middle of a handshake message.
928 if (s->init_num != 0 || readbytes != 1 || p[0] != SSL3_MT_CCS) {
929 al = SSL_AD_UNEXPECTED_MESSAGE;
930 SSLerr(SSL_F_TLS_GET_MESSAGE_HEADER,
931 SSL_R_BAD_CHANGE_CIPHER_SPEC);
934 s->s3->tmp.message_type = *mt = SSL3_MT_CHANGE_CIPHER_SPEC;
935 s->init_num = readbytes - 1;
936 s->init_msg = s->init_buf->data;
937 s->s3->tmp.message_size = readbytes;
939 } else if (recvd_type != SSL3_RT_HANDSHAKE) {
940 al = SSL_AD_UNEXPECTED_MESSAGE;
941 SSLerr(SSL_F_TLS_GET_MESSAGE_HEADER, SSL_R_CCS_RECEIVED_EARLY);
944 s->init_num += readbytes;
949 if (s->statem.hand_state != TLS_ST_OK
950 && p[0] == SSL3_MT_HELLO_REQUEST)
952 * The server may always send 'Hello Request' messages --
953 * we are doing a handshake anyway now, so ignore them if
954 * their format is correct. Does not count for 'Finished'
957 if (p[1] == 0 && p[2] == 0 && p[3] == 0) {
962 s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE,
963 p, SSL3_HM_HEADER_LENGTH, s,
964 s->msg_callback_arg);
966 } while (skip_message);
967 /* s->init_num == SSL3_HM_HEADER_LENGTH */
970 s->s3->tmp.message_type = *(p++);
972 if (RECORD_LAYER_is_sslv2_record(&s->rlayer)) {
974 * Only happens with SSLv3+ in an SSLv2 backward compatible
977 * Total message size is the remaining record bytes to read
978 * plus the SSL3_HM_HEADER_LENGTH bytes that we already read
980 l = RECORD_LAYER_get_rrec_length(&s->rlayer)
981 + SSL3_HM_HEADER_LENGTH;
982 s->s3->tmp.message_size = l;
984 s->init_msg = s->init_buf->data;
985 s->init_num = SSL3_HM_HEADER_LENGTH;
988 /* BUF_MEM_grow takes an 'int' parameter */
989 if (l > (INT_MAX - SSL3_HM_HEADER_LENGTH)) {
990 al = SSL_AD_ILLEGAL_PARAMETER;
991 SSLerr(SSL_F_TLS_GET_MESSAGE_HEADER, SSL_R_EXCESSIVE_MESSAGE_SIZE);
994 s->s3->tmp.message_size = l;
996 s->init_msg = s->init_buf->data + SSL3_HM_HEADER_LENGTH;
1002 ssl3_send_alert(s, SSL3_AL_FATAL, al);
1006 int tls_get_message_body(SSL *s, size_t *len)
1008 size_t n, readbytes;
1012 if (s->s3->tmp.message_type == SSL3_MT_CHANGE_CIPHER_SPEC) {
1013 /* We've already read everything in */
1014 *len = (unsigned long)s->init_num;
1019 n = s->s3->tmp.message_size - s->init_num;
1021 i = s->method->ssl_read_bytes(s, SSL3_RT_HANDSHAKE, NULL,
1022 &p[s->init_num], n, 0, &readbytes);
1024 s->rwstate = SSL_READING;
1028 s->init_num += readbytes;
1032 #ifndef OPENSSL_NO_NEXTPROTONEG
1034 * If receiving Finished, record MAC of prior handshake messages for
1035 * Finished verification.
1037 if (*s->init_buf->data == SSL3_MT_FINISHED)
1041 /* Feed this message into MAC computation. */
1042 if (RECORD_LAYER_is_sslv2_record(&s->rlayer)) {
1043 if (!ssl3_finish_mac(s, (unsigned char *)s->init_buf->data,
1045 SSLerr(SSL_F_TLS_GET_MESSAGE_BODY, ERR_R_EVP_LIB);
1046 ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR);
1050 if (s->msg_callback)
1051 s->msg_callback(0, SSL2_VERSION, 0, s->init_buf->data,
1052 (size_t)s->init_num, s, s->msg_callback_arg);
1054 if (!ssl3_finish_mac(s, (unsigned char *)s->init_buf->data,
1055 s->init_num + SSL3_HM_HEADER_LENGTH)) {
1056 SSLerr(SSL_F_TLS_GET_MESSAGE_BODY, ERR_R_EVP_LIB);
1057 ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR);
1061 if (s->msg_callback)
1062 s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE, s->init_buf->data,
1063 (size_t)s->init_num + SSL3_HM_HEADER_LENGTH, s,
1064 s->msg_callback_arg);
1071 int ssl_cert_type(const X509 *x, const EVP_PKEY *pk)
1073 if (pk == NULL && (pk = X509_get0_pubkey(x)) == NULL)
1076 switch (EVP_PKEY_id(pk)) {
1080 return SSL_PKEY_RSA_ENC;
1082 return SSL_PKEY_DSA_SIGN;
1083 #ifndef OPENSSL_NO_EC
1085 return SSL_PKEY_ECC;
1087 #ifndef OPENSSL_NO_GOST
1088 case NID_id_GostR3410_2001:
1089 return SSL_PKEY_GOST01;
1090 case NID_id_GostR3410_2012_256:
1091 return SSL_PKEY_GOST12_256;
1092 case NID_id_GostR3410_2012_512:
1093 return SSL_PKEY_GOST12_512;
1098 int ssl_verify_alarm_type(long type)
1103 case X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT:
1104 case X509_V_ERR_UNABLE_TO_GET_CRL:
1105 case X509_V_ERR_UNABLE_TO_GET_CRL_ISSUER:
1106 al = SSL_AD_UNKNOWN_CA;
1108 case X509_V_ERR_UNABLE_TO_DECRYPT_CERT_SIGNATURE:
1109 case X509_V_ERR_UNABLE_TO_DECRYPT_CRL_SIGNATURE:
1110 case X509_V_ERR_UNABLE_TO_DECODE_ISSUER_PUBLIC_KEY:
1111 case X509_V_ERR_ERROR_IN_CERT_NOT_BEFORE_FIELD:
1112 case X509_V_ERR_ERROR_IN_CERT_NOT_AFTER_FIELD:
1113 case X509_V_ERR_ERROR_IN_CRL_LAST_UPDATE_FIELD:
1114 case X509_V_ERR_ERROR_IN_CRL_NEXT_UPDATE_FIELD:
1115 case X509_V_ERR_CERT_NOT_YET_VALID:
1116 case X509_V_ERR_CRL_NOT_YET_VALID:
1117 case X509_V_ERR_CERT_UNTRUSTED:
1118 case X509_V_ERR_CERT_REJECTED:
1119 case X509_V_ERR_HOSTNAME_MISMATCH:
1120 case X509_V_ERR_EMAIL_MISMATCH:
1121 case X509_V_ERR_IP_ADDRESS_MISMATCH:
1122 case X509_V_ERR_DANE_NO_MATCH:
1123 case X509_V_ERR_EE_KEY_TOO_SMALL:
1124 case X509_V_ERR_CA_KEY_TOO_SMALL:
1125 case X509_V_ERR_CA_MD_TOO_WEAK:
1126 al = SSL_AD_BAD_CERTIFICATE;
1128 case X509_V_ERR_CERT_SIGNATURE_FAILURE:
1129 case X509_V_ERR_CRL_SIGNATURE_FAILURE:
1130 al = SSL_AD_DECRYPT_ERROR;
1132 case X509_V_ERR_CERT_HAS_EXPIRED:
1133 case X509_V_ERR_CRL_HAS_EXPIRED:
1134 al = SSL_AD_CERTIFICATE_EXPIRED;
1136 case X509_V_ERR_CERT_REVOKED:
1137 al = SSL_AD_CERTIFICATE_REVOKED;
1139 case X509_V_ERR_UNSPECIFIED:
1140 case X509_V_ERR_OUT_OF_MEM:
1141 case X509_V_ERR_INVALID_CALL:
1142 case X509_V_ERR_STORE_LOOKUP:
1143 al = SSL_AD_INTERNAL_ERROR;
1145 case X509_V_ERR_DEPTH_ZERO_SELF_SIGNED_CERT:
1146 case X509_V_ERR_SELF_SIGNED_CERT_IN_CHAIN:
1147 case X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT_LOCALLY:
1148 case X509_V_ERR_UNABLE_TO_VERIFY_LEAF_SIGNATURE:
1149 case X509_V_ERR_CERT_CHAIN_TOO_LONG:
1150 case X509_V_ERR_PATH_LENGTH_EXCEEDED:
1151 case X509_V_ERR_INVALID_CA:
1152 al = SSL_AD_UNKNOWN_CA;
1154 case X509_V_ERR_APPLICATION_VERIFICATION:
1155 al = SSL_AD_HANDSHAKE_FAILURE;
1157 case X509_V_ERR_INVALID_PURPOSE:
1158 al = SSL_AD_UNSUPPORTED_CERTIFICATE;
1161 al = SSL_AD_CERTIFICATE_UNKNOWN;
1167 int ssl_allow_compression(SSL *s)
1169 if (s->options & SSL_OP_NO_COMPRESSION)
1171 return ssl_security(s, SSL_SECOP_COMPRESSION, 0, 0, NULL);
1174 static int version_cmp(const SSL *s, int a, int b)
1176 int dtls = SSL_IS_DTLS(s);
1181 return a < b ? -1 : 1;
1182 return DTLS_VERSION_LT(a, b) ? -1 : 1;
1187 const SSL_METHOD *(*cmeth) (void);
1188 const SSL_METHOD *(*smeth) (void);
1191 #if TLS_MAX_VERSION != TLS1_3_VERSION
1192 # error Code needs update for TLS_method() support beyond TLS1_3_VERSION.
1195 static const version_info tls_version_table[] = {
1196 #ifndef OPENSSL_NO_TLS1_3
1197 {TLS1_3_VERSION, tlsv1_3_client_method, tlsv1_3_server_method},
1199 {TLS1_3_VERSION, NULL, NULL},
1201 #ifndef OPENSSL_NO_TLS1_2
1202 {TLS1_2_VERSION, tlsv1_2_client_method, tlsv1_2_server_method},
1204 {TLS1_2_VERSION, NULL, NULL},
1206 #ifndef OPENSSL_NO_TLS1_1
1207 {TLS1_1_VERSION, tlsv1_1_client_method, tlsv1_1_server_method},
1209 {TLS1_1_VERSION, NULL, NULL},
1211 #ifndef OPENSSL_NO_TLS1
1212 {TLS1_VERSION, tlsv1_client_method, tlsv1_server_method},
1214 {TLS1_VERSION, NULL, NULL},
1216 #ifndef OPENSSL_NO_SSL3
1217 {SSL3_VERSION, sslv3_client_method, sslv3_server_method},
1219 {SSL3_VERSION, NULL, NULL},
1224 #if DTLS_MAX_VERSION != DTLS1_2_VERSION
1225 # error Code needs update for DTLS_method() support beyond DTLS1_2_VERSION.
1228 static const version_info dtls_version_table[] = {
1229 #ifndef OPENSSL_NO_DTLS1_2
1230 {DTLS1_2_VERSION, dtlsv1_2_client_method, dtlsv1_2_server_method},
1232 {DTLS1_2_VERSION, NULL, NULL},
1234 #ifndef OPENSSL_NO_DTLS1
1235 {DTLS1_VERSION, dtlsv1_client_method, dtlsv1_server_method},
1236 {DTLS1_BAD_VER, dtls_bad_ver_client_method, NULL},
1238 {DTLS1_VERSION, NULL, NULL},
1239 {DTLS1_BAD_VER, NULL, NULL},
1245 * ssl_method_error - Check whether an SSL_METHOD is enabled.
1247 * @s: The SSL handle for the candidate method
1248 * @method: the intended method.
1250 * Returns 0 on success, or an SSL error reason on failure.
1252 static int ssl_method_error(const SSL *s, const SSL_METHOD *method)
1254 int version = method->version;
1256 if ((s->min_proto_version != 0 &&
1257 version_cmp(s, version, s->min_proto_version) < 0) ||
1258 ssl_security(s, SSL_SECOP_VERSION, 0, version, NULL) == 0)
1259 return SSL_R_VERSION_TOO_LOW;
1261 if (s->max_proto_version != 0 &&
1262 version_cmp(s, version, s->max_proto_version) > 0)
1263 return SSL_R_VERSION_TOO_HIGH;
1265 if ((s->options & method->mask) != 0)
1266 return SSL_R_UNSUPPORTED_PROTOCOL;
1267 if ((method->flags & SSL_METHOD_NO_SUITEB) != 0 && tls1_suiteb(s))
1268 return SSL_R_AT_LEAST_TLS_1_2_NEEDED_IN_SUITEB_MODE;
1269 else if ((method->flags & SSL_METHOD_NO_FIPS) != 0 && FIPS_mode())
1270 return SSL_R_AT_LEAST_TLS_1_0_NEEDED_IN_FIPS_MODE;
1276 * ssl_version_supported - Check that the specified `version` is supported by
1279 * @s: The SSL handle for the candidate method
1280 * @version: Protocol version to test against
1282 * Returns 1 when supported, otherwise 0
1284 int ssl_version_supported(const SSL *s, int version)
1286 const version_info *vent;
1287 const version_info *table;
1289 switch (s->method->version) {
1291 /* Version should match method version for non-ANY method */
1292 return version_cmp(s, version, s->version) == 0;
1293 case TLS_ANY_VERSION:
1294 table = tls_version_table;
1296 case DTLS_ANY_VERSION:
1297 table = dtls_version_table;
1302 vent->version != 0 && version_cmp(s, version, vent->version) <= 0;
1304 if (vent->cmeth != NULL &&
1305 version_cmp(s, version, vent->version) == 0 &&
1306 ssl_method_error(s, vent->cmeth()) == 0) {
1314 * ssl_check_version_downgrade - In response to RFC7507 SCSV version
1315 * fallback indication from a client check whether we're using the highest
1316 * supported protocol version.
1318 * @s server SSL handle.
1320 * Returns 1 when using the highest enabled version, 0 otherwise.
1322 int ssl_check_version_downgrade(SSL *s)
1324 const version_info *vent;
1325 const version_info *table;
1328 * Check that the current protocol is the highest enabled version
1329 * (according to s->ctx->method, as version negotiation may have changed
1332 if (s->version == s->ctx->method->version)
1336 * Apparently we're using a version-flexible SSL_METHOD (not at its
1337 * highest protocol version).
1339 if (s->ctx->method->version == TLS_method()->version)
1340 table = tls_version_table;
1341 else if (s->ctx->method->version == DTLS_method()->version)
1342 table = dtls_version_table;
1344 /* Unexpected state; fail closed. */
1348 for (vent = table; vent->version != 0; ++vent) {
1349 if (vent->smeth != NULL && ssl_method_error(s, vent->smeth()) == 0)
1350 return s->version == vent->version;
1356 * ssl_set_version_bound - set an upper or lower bound on the supported (D)TLS
1357 * protocols, provided the initial (D)TLS method is version-flexible. This
1358 * function sanity-checks the proposed value and makes sure the method is
1359 * version-flexible, then sets the limit if all is well.
1361 * @method_version: The version of the current SSL_METHOD.
1362 * @version: the intended limit.
1363 * @bound: pointer to limit to be updated.
1365 * Returns 1 on success, 0 on failure.
1367 int ssl_set_version_bound(int method_version, int version, int *bound)
1375 * Restrict TLS methods to TLS protocol versions.
1376 * Restrict DTLS methods to DTLS protocol versions.
1377 * Note, DTLS version numbers are decreasing, use comparison macros.
1379 * Note that for both lower-bounds we use explicit versions, not
1380 * (D)TLS_MIN_VERSION. This is because we don't want to break user
1381 * configurations. If the MIN (supported) version ever rises, the user's
1382 * "floor" remains valid even if no longer available. We don't expect the
1383 * MAX ceiling to ever get lower, so making that variable makes sense.
1385 switch (method_version) {
1388 * XXX For fixed version methods, should we always fail and not set any
1389 * bounds, always succeed and not set any bounds, or set the bounds and
1390 * arrange to fail later if they are not met? At present fixed-version
1391 * methods are not subject to controls that disable individual protocol
1396 case TLS_ANY_VERSION:
1397 if (version < SSL3_VERSION || version > TLS_MAX_VERSION)
1401 case DTLS_ANY_VERSION:
1402 if (DTLS_VERSION_GT(version, DTLS_MAX_VERSION) ||
1403 DTLS_VERSION_LT(version, DTLS1_BAD_VER))
1413 * ssl_choose_server_version - Choose server (D)TLS version. Called when the
1414 * client HELLO is received to select the final server protocol version and
1415 * the version specific method.
1417 * @s: server SSL handle.
1419 * Returns 0 on success or an SSL error reason number on failure.
1421 int ssl_choose_server_version(SSL *s, CLIENTHELLO_MSG *hello)
1424 * With version-flexible methods we have an initial state with:
1426 * s->method->version == (D)TLS_ANY_VERSION,
1427 * s->version == (D)TLS_MAX_VERSION.
1429 * So we detect version-flexible methods via the method version, not the
1432 int server_version = s->method->version;
1433 int client_version = hello->legacy_version;
1434 const version_info *vent;
1435 const version_info *table;
1437 RAW_EXTENSION *suppversions;
1439 s->client_version = client_version;
1441 switch (server_version) {
1444 * TODO(TLS1.3): This check will fail if someone attempts to do
1445 * renegotiation in TLS1.3 at the moment. We need to ensure we disable
1446 * renegotiation for TLS1.3
1448 if (version_cmp(s, client_version, s->version) < 0)
1449 return SSL_R_WRONG_SSL_VERSION;
1451 * If this SSL handle is not from a version flexible method we don't
1452 * (and never did) check min/max FIPS or Suite B constraints. Hope
1453 * that's OK. It is up to the caller to not choose fixed protocol
1454 * versions they don't want. If not, then easy to fix, just return
1455 * ssl_method_error(s, s->method)
1458 case TLS_ANY_VERSION:
1459 table = tls_version_table;
1461 case DTLS_ANY_VERSION:
1462 table = dtls_version_table;
1466 suppversions = &hello->pre_proc_exts[TLSEXT_IDX_supported_versions];
1468 if (suppversions->present && !SSL_IS_DTLS(s)) {
1469 unsigned int candidate_vers = 0;
1470 unsigned int best_vers = 0;
1471 const SSL_METHOD *best_method = NULL;
1472 PACKET versionslist;
1474 suppversions->parsed = 1;
1476 if (!PACKET_as_length_prefixed_1(&suppversions->data, &versionslist)) {
1477 /* Trailing or invalid data? */
1478 return SSL_R_LENGTH_MISMATCH;
1481 while (PACKET_get_net_2(&versionslist, &candidate_vers)) {
1482 /* TODO(TLS1.3): Remove this before release */
1483 if (candidate_vers == TLS1_3_VERSION_DRAFT)
1484 candidate_vers = TLS1_3_VERSION;
1486 * TODO(TLS1.3): There is some discussion on the TLS list about
1487 * wheter to ignore versions <TLS1.2 in supported_versions. At the
1488 * moment we honour them if present. To be reviewed later
1490 if (version_cmp(s, candidate_vers, best_vers) <= 0)
1493 vent->version != 0 && vent->version != (int)candidate_vers;
1496 if (vent->version != 0 && vent->smeth != NULL) {
1497 const SSL_METHOD *method;
1499 method = vent->smeth();
1500 if (ssl_method_error(s, method) == 0) {
1501 best_vers = candidate_vers;
1502 best_method = method;
1506 if (PACKET_remaining(&versionslist) != 0) {
1507 /* Trailing data? */
1508 return SSL_R_LENGTH_MISMATCH;
1511 if (best_vers > 0) {
1512 s->version = best_vers;
1513 s->method = best_method;
1516 return SSL_R_UNSUPPORTED_PROTOCOL;
1520 * If the supported versions extension isn't present, then the highest
1521 * version we can negotiate is TLSv1.2
1523 if (version_cmp(s, client_version, TLS1_3_VERSION) >= 0)
1524 client_version = TLS1_2_VERSION;
1527 * No supported versions extension, so we just use the version supplied in
1530 for (vent = table; vent->version != 0; ++vent) {
1531 const SSL_METHOD *method;
1533 if (vent->smeth == NULL ||
1534 version_cmp(s, client_version, vent->version) < 0)
1536 method = vent->smeth();
1537 if (ssl_method_error(s, method) == 0) {
1538 s->version = vent->version;
1544 return disabled ? SSL_R_UNSUPPORTED_PROTOCOL : SSL_R_VERSION_TOO_LOW;
1548 * ssl_choose_client_version - Choose client (D)TLS version. Called when the
1549 * server HELLO is received to select the final client protocol version and
1550 * the version specific method.
1552 * @s: client SSL handle.
1553 * @version: The proposed version from the server's HELLO.
1555 * Returns 0 on success or an SSL error reason number on failure.
1557 int ssl_choose_client_version(SSL *s, int version)
1559 const version_info *vent;
1560 const version_info *table;
1562 /* TODO(TLS1.3): Remove this before release */
1563 if (version == TLS1_3_VERSION_DRAFT)
1564 version = TLS1_3_VERSION;
1566 switch (s->method->version) {
1568 if (version != s->version)
1569 return SSL_R_WRONG_SSL_VERSION;
1571 * If this SSL handle is not from a version flexible method we don't
1572 * (and never did) check min/max, FIPS or Suite B constraints. Hope
1573 * that's OK. It is up to the caller to not choose fixed protocol
1574 * versions they don't want. If not, then easy to fix, just return
1575 * ssl_method_error(s, s->method)
1578 case TLS_ANY_VERSION:
1579 table = tls_version_table;
1581 case DTLS_ANY_VERSION:
1582 table = dtls_version_table;
1586 for (vent = table; vent->version != 0; ++vent) {
1587 const SSL_METHOD *method;
1590 if (version != vent->version)
1592 if (vent->cmeth == NULL)
1594 method = vent->cmeth();
1595 err = ssl_method_error(s, method);
1599 s->version = version;
1603 return SSL_R_UNSUPPORTED_PROTOCOL;
1607 * ssl_get_client_min_max_version - get minimum and maximum client version
1608 * @s: The SSL connection
1609 * @min_version: The minimum supported version
1610 * @max_version: The maximum supported version
1612 * Work out what version we should be using for the initial ClientHello if the
1613 * version is initially (D)TLS_ANY_VERSION. We apply any explicit SSL_OP_NO_xxx
1614 * options, the MinProtocol and MaxProtocol configuration commands, any Suite B
1615 * or FIPS_mode() constraints and any floor imposed by the security level here,
1616 * so we don't advertise the wrong protocol version to only reject the outcome later.
1618 * Computing the right floor matters. If, e.g., TLS 1.0 and 1.2 are enabled,
1619 * TLS 1.1 is disabled, but the security level, Suite-B and/or MinProtocol
1620 * only allow TLS 1.2, we want to advertise TLS1.2, *not* TLS1.
1622 * Returns 0 on success or an SSL error reason number on failure. On failure
1623 * min_version and max_version will also be set to 0.
1625 int ssl_get_client_min_max_version(const SSL *s, int *min_version,
1630 const SSL_METHOD *single = NULL;
1631 const SSL_METHOD *method;
1632 const version_info *table;
1633 const version_info *vent;
1635 switch (s->method->version) {
1638 * If this SSL handle is not from a version flexible method we don't
1639 * (and never did) check min/max FIPS or Suite B constraints. Hope
1640 * that's OK. It is up to the caller to not choose fixed protocol
1641 * versions they don't want. If not, then easy to fix, just return
1642 * ssl_method_error(s, s->method)
1644 *min_version = *max_version = s->version;
1646 case TLS_ANY_VERSION:
1647 table = tls_version_table;
1649 case DTLS_ANY_VERSION:
1650 table = dtls_version_table;
1655 * SSL_OP_NO_X disables all protocols above X *if* there are some protocols
1656 * below X enabled. This is required in order to maintain the "version
1657 * capability" vector contiguous. Any versions with a NULL client method
1658 * (protocol version client is disabled at compile-time) is also a "hole".
1660 * Our initial state is hole == 1, version == 0. That is, versions above
1661 * the first version in the method table are disabled (a "hole" above
1662 * the valid protocol entries) and we don't have a selected version yet.
1664 * Whenever "hole == 1", and we hit an enabled method, its version becomes
1665 * the selected version, and the method becomes a candidate "single"
1666 * method. We're no longer in a hole, so "hole" becomes 0.
1668 * If "hole == 0" and we hit an enabled method, then "single" is cleared,
1669 * as we support a contiguous range of at least two methods. If we hit
1670 * a disabled method, then hole becomes true again, but nothing else
1671 * changes yet, because all the remaining methods may be disabled too.
1672 * If we again hit an enabled method after the new hole, it becomes
1673 * selected, as we start from scratch.
1675 *min_version = version = 0;
1677 for (vent = table; vent->version != 0; ++vent) {
1679 * A table entry with a NULL client method is still a hole in the
1680 * "version capability" vector.
1682 if (vent->cmeth == NULL) {
1686 method = vent->cmeth();
1687 if (ssl_method_error(s, method) != 0) {
1691 *min_version = method->version;
1693 version = (single = method)->version;
1694 *min_version = version;
1699 *max_version = version;
1701 /* Fail if everything is disabled */
1703 return SSL_R_NO_PROTOCOLS_AVAILABLE;
1709 * ssl_set_client_hello_version - Work out what version we should be using for
1710 * the initial ClientHello.legacy_version field.
1712 * @s: client SSL handle.
1714 * Returns 0 on success or an SSL error reason number on failure.
1716 int ssl_set_client_hello_version(SSL *s)
1718 int ver_min, ver_max, ret;
1720 ret = ssl_get_client_min_max_version(s, &ver_min, &ver_max);
1725 s->version = ver_max;
1727 /* TLS1.3 always uses TLS1.2 in the legacy_version field */
1728 if (!SSL_IS_DTLS(s) && ver_max > TLS1_2_VERSION)
1729 ver_max = TLS1_2_VERSION;
1731 s->client_version = ver_max;