/* * Copyright 1995-2016 The OpenSSL Project Authors. All Rights Reserved. * * Licensed under the OpenSSL license (the "License"). You may not use * this file except in compliance with the License. You can obtain a copy * in the file LICENSE in the source distribution or at * https://www.openssl.org/source/license.html */ /* ==================================================================== * Copyright 2002 Sun Microsystems, Inc. ALL RIGHTS RESERVED. * ECC cipher suite support in OpenSSL originally developed by * SUN MICROSYSTEMS, INC., and contributed to the OpenSSL project. */ #include #include #include #include "../ssl_locl.h" #include "statem_locl.h" #include #include #include #include /* * send s->init_buf in records of type 'type' (SSL3_RT_HANDSHAKE or * SSL3_RT_CHANGE_CIPHER_SPEC) */ int ssl3_do_write(SSL *s, int type) { int ret; size_t written = 0; ret = ssl3_write_bytes(s, type, &s->init_buf->data[s->init_off], s->init_num, &written); if (ret < 0) return (-1); if (type == SSL3_RT_HANDSHAKE) /* * should not be done for 'Hello Request's, but in that case we'll * ignore the result anyway */ if (!ssl3_finish_mac(s, (unsigned char *)&s->init_buf->data[s->init_off], written)) return -1; if (written == s->init_num) { if (s->msg_callback) s->msg_callback(1, s->version, type, s->init_buf->data, (size_t)(s->init_off + s->init_num), s, s->msg_callback_arg); return (1); } s->init_off += written; s->init_num -= written; return (0); } int tls_close_construct_packet(SSL *s, WPACKET *pkt, int htype) { size_t msglen; if ((htype != SSL3_MT_CHANGE_CIPHER_SPEC && !WPACKET_close(pkt)) || !WPACKET_get_length(pkt, &msglen) || msglen > INT_MAX) return 0; s->init_num = (int)msglen; s->init_off = 0; return 1; } int tls_setup_handshake(SSL *s) { if (!ssl3_init_finished_mac(s)) return 0; if (s->server) { if (SSL_IS_FIRST_HANDSHAKE(s)) { s->ctx->stats.sess_accept++; } else if (!s->s3->send_connection_binding && !(s->options & SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION)) { /* * Server attempting to renegotiate with client that doesn't * support secure renegotiation. */ SSLerr(SSL_F_TLS_SETUP_HANDSHAKE, SSL_R_UNSAFE_LEGACY_RENEGOTIATION_DISABLED); ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_HANDSHAKE_FAILURE); return 0; } else { s->ctx->stats.sess_accept_renegotiate++; s->s3->tmp.cert_request = 0; } } else { if (SSL_IS_FIRST_HANDSHAKE(s)) s->ctx->stats.sess_connect++; else s->ctx->stats.sess_connect_renegotiate++; /* mark client_random uninitialized */ memset(s->s3->client_random, 0, sizeof(s->s3->client_random)); s->hit = 0; s->s3->tmp.cert_req = 0; if (SSL_IS_DTLS(s)) s->statem.use_timer = 1; } return 1; } /* * Size of the to-be-signed TLS13 data, without the hash size itself: * 64 bytes of value 32, 33 context bytes, 1 byte separator */ #define TLS13_TBS_START_SIZE 64 #define TLS13_TBS_PREAMBLE_SIZE (TLS13_TBS_START_SIZE + 33 + 1) static int get_cert_verify_tbs_data(SSL *s, unsigned char *tls13tbs, void **hdata, size_t *hdatalen) { static const char *servercontext = "TLS 1.3, server CertificateVerify"; static const char *clientcontext = "TLS 1.3, client CertificateVerify"; if (SSL_IS_TLS13(s)) { size_t hashlen; /* Set the first 64 bytes of to-be-signed data to octet 32 */ memset(tls13tbs, 32, TLS13_TBS_START_SIZE); /* This copies the 33 bytes of context plus the 0 separator byte */ if (s->statem.hand_state == TLS_ST_CR_CERT_VRFY || s->statem.hand_state == TLS_ST_SW_CERT_VRFY) strcpy((char *)tls13tbs + TLS13_TBS_START_SIZE, servercontext); else strcpy((char *)tls13tbs + TLS13_TBS_START_SIZE, clientcontext); /* * If we're currently reading then we need to use the saved handshake * hash value. We can't use the current handshake hash state because * that includes the CertVerify itself. */ if (s->statem.hand_state == TLS_ST_CR_CERT_VRFY || s->statem.hand_state == TLS_ST_SR_CERT_VRFY) { memcpy(tls13tbs + TLS13_TBS_PREAMBLE_SIZE, s->cert_verify_hash, s->cert_verify_hash_len); hashlen = s->cert_verify_hash_len; } else if (!ssl_handshake_hash(s, tls13tbs + TLS13_TBS_PREAMBLE_SIZE, EVP_MAX_MD_SIZE, &hashlen)) { return 0; } *hdata = tls13tbs; *hdatalen = TLS13_TBS_PREAMBLE_SIZE + hashlen; } else { size_t retlen; retlen = BIO_get_mem_data(s->s3->handshake_buffer, hdata); if (retlen <= 0) return 0; *hdatalen = retlen; } return 1; } int tls_construct_cert_verify(SSL *s, WPACKET *pkt) { EVP_PKEY *pkey; const EVP_MD *md; EVP_MD_CTX *mctx = NULL; EVP_PKEY_CTX *pctx = NULL; size_t hdatalen = 0, siglen = 0; void *hdata; unsigned char *sig = NULL; unsigned char tls13tbs[TLS13_TBS_PREAMBLE_SIZE + EVP_MAX_MD_SIZE]; int pktype, ispss = 0; if (s->server) { /* Only happens in TLSv1.3 */ /* * TODO(TLS1.3): This needs to change. We should not get this from the * cipher. However, for now, we have not done the work to separate the * certificate type from the ciphersuite */ pkey = ssl_get_sign_pkey(s, s->s3->tmp.new_cipher, &md); if (pkey == NULL) goto err; } else { md = s->s3->tmp.md[s->cert->key - s->cert->pkeys]; pkey = s->cert->key->privatekey; } pktype = EVP_PKEY_id(pkey); mctx = EVP_MD_CTX_new(); if (mctx == NULL) { SSLerr(SSL_F_TLS_CONSTRUCT_CERT_VERIFY, ERR_R_MALLOC_FAILURE); goto err; } /* Get the data to be signed */ if (!get_cert_verify_tbs_data(s, tls13tbs, &hdata, &hdatalen)) { SSLerr(SSL_F_TLS_CONSTRUCT_CERT_VERIFY, ERR_R_INTERNAL_ERROR); goto err; } if (SSL_USE_SIGALGS(s) && !tls12_get_sigandhash(s, pkt, pkey, md, &ispss)) { SSLerr(SSL_F_TLS_CONSTRUCT_CERT_VERIFY, ERR_R_INTERNAL_ERROR); goto err; } #ifdef SSL_DEBUG fprintf(stderr, "Using client alg %s\n", EVP_MD_name(md)); #endif siglen = EVP_PKEY_size(pkey); sig = OPENSSL_malloc(siglen); if (sig == NULL) { SSLerr(SSL_F_TLS_CONSTRUCT_CERT_VERIFY, ERR_R_MALLOC_FAILURE); goto err; } if (EVP_DigestSignInit(mctx, &pctx, md, NULL, pkey) <= 0 || EVP_DigestSignUpdate(mctx, hdata, hdatalen) <= 0) { SSLerr(SSL_F_TLS_CONSTRUCT_CERT_VERIFY, ERR_R_EVP_LIB); goto err; } if (ispss) { if (EVP_PKEY_CTX_set_rsa_padding(pctx, RSA_PKCS1_PSS_PADDING) <= 0 /* -1 here means set saltlen to the digest len */ || EVP_PKEY_CTX_set_rsa_pss_saltlen(pctx, -1) <= 0) { SSLerr(SSL_F_TLS_CONSTRUCT_CERT_VERIFY, ERR_R_EVP_LIB); goto err; } } else if (s->version == SSL3_VERSION) { if (!EVP_MD_CTX_ctrl(mctx, EVP_CTRL_SSL3_MASTER_SECRET, (int)s->session->master_key_length, s->session->master_key)) { SSLerr(SSL_F_TLS_CONSTRUCT_CERT_VERIFY, ERR_R_EVP_LIB); goto err; } } if (EVP_DigestSignFinal(mctx, sig, &siglen) <= 0) { SSLerr(SSL_F_TLS_CONSTRUCT_CERT_VERIFY, ERR_R_EVP_LIB); goto err; } #ifndef OPENSSL_NO_GOST { if (pktype == NID_id_GostR3410_2001 || pktype == NID_id_GostR3410_2012_256 || pktype == NID_id_GostR3410_2012_512) BUF_reverse(sig, NULL, siglen); } #endif if (!WPACKET_sub_memcpy_u16(pkt, sig, siglen)) { SSLerr(SSL_F_TLS_CONSTRUCT_CERT_VERIFY, ERR_R_INTERNAL_ERROR); goto err; } /* Digest cached records and discard handshake buffer */ if (!ssl3_digest_cached_records(s, 0)) goto err; OPENSSL_free(sig); EVP_MD_CTX_free(mctx); return 1; err: OPENSSL_free(sig); EVP_MD_CTX_free(mctx); ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR); return 0; } MSG_PROCESS_RETURN tls_process_cert_verify(SSL *s, PACKET *pkt) { EVP_PKEY *pkey = NULL; const unsigned char *data; #ifndef OPENSSL_NO_GOST unsigned char *gost_data = NULL; #endif int al = SSL_AD_INTERNAL_ERROR, ret = MSG_PROCESS_ERROR; int type = 0, j, pktype, ispss = 0; unsigned int len; X509 *peer; const EVP_MD *md = NULL; size_t hdatalen = 0; void *hdata; unsigned char tls13tbs[TLS13_TBS_PREAMBLE_SIZE + EVP_MAX_MD_SIZE]; EVP_MD_CTX *mctx = EVP_MD_CTX_new(); EVP_PKEY_CTX *pctx = NULL; if (mctx == NULL) { SSLerr(SSL_F_TLS_PROCESS_CERT_VERIFY, ERR_R_MALLOC_FAILURE); goto f_err; } peer = s->session->peer; pkey = X509_get0_pubkey(peer); pktype = EVP_PKEY_id(pkey); type = X509_certificate_type(peer, pkey); if (!(type & EVP_PKT_SIGN)) { SSLerr(SSL_F_TLS_PROCESS_CERT_VERIFY, SSL_R_SIGNATURE_FOR_NON_SIGNING_CERTIFICATE); al = SSL_AD_ILLEGAL_PARAMETER; goto f_err; } /* Check for broken implementations of GOST ciphersuites */ /* * If key is GOST and n is exactly 64, it is bare signature without * length field (CryptoPro implementations at least till CSP 4.0) */ #ifndef OPENSSL_NO_GOST if (PACKET_remaining(pkt) == 64 && EVP_PKEY_id(pkey) == NID_id_GostR3410_2001) { len = 64; } else #endif { if (SSL_USE_SIGALGS(s)) { int rv; unsigned int sigalg; if (!PACKET_get_net_2(pkt, &sigalg)) { al = SSL_AD_DECODE_ERROR; goto f_err; } rv = tls12_check_peer_sigalg(&md, s, sigalg, pkey); if (rv == -1) { goto f_err; } else if (rv == 0) { al = SSL_AD_DECODE_ERROR; goto f_err; } ispss = SIGID_IS_PSS(sigalg); #ifdef SSL_DEBUG fprintf(stderr, "USING TLSv1.2 HASH %s\n", EVP_MD_name(md)); #endif } else { /* Use default digest for this key type */ int idx = ssl_cert_type(NULL, pkey); if (idx >= 0) md = s->s3->tmp.md[idx]; if (md == NULL) { al = SSL_AD_INTERNAL_ERROR; goto f_err; } } if (!PACKET_get_net_2(pkt, &len)) { SSLerr(SSL_F_TLS_PROCESS_CERT_VERIFY, SSL_R_LENGTH_MISMATCH); al = SSL_AD_DECODE_ERROR; goto f_err; } } j = EVP_PKEY_size(pkey); if (((int)len > j) || ((int)PACKET_remaining(pkt) > j) || (PACKET_remaining(pkt) == 0)) { SSLerr(SSL_F_TLS_PROCESS_CERT_VERIFY, SSL_R_WRONG_SIGNATURE_SIZE); al = SSL_AD_DECODE_ERROR; goto f_err; } if (!PACKET_get_bytes(pkt, &data, len)) { SSLerr(SSL_F_TLS_PROCESS_CERT_VERIFY, SSL_R_LENGTH_MISMATCH); al = SSL_AD_DECODE_ERROR; goto f_err; } if (!get_cert_verify_tbs_data(s, tls13tbs, &hdata, &hdatalen)) { SSLerr(SSL_F_TLS_PROCESS_CERT_VERIFY, ERR_R_INTERNAL_ERROR); goto f_err; } #ifdef SSL_DEBUG fprintf(stderr, "Using client verify alg %s\n", EVP_MD_name(md)); #endif if (EVP_DigestVerifyInit(mctx, &pctx, md, NULL, pkey) <= 0 || EVP_DigestVerifyUpdate(mctx, hdata, hdatalen) <= 0) { SSLerr(SSL_F_TLS_PROCESS_CERT_VERIFY, ERR_R_EVP_LIB); goto f_err; } #ifndef OPENSSL_NO_GOST { if (pktype == NID_id_GostR3410_2001 || pktype == NID_id_GostR3410_2012_256 || pktype == NID_id_GostR3410_2012_512) { if ((gost_data = OPENSSL_malloc(len)) == NULL) { SSLerr(SSL_F_TLS_PROCESS_CERT_VERIFY, ERR_R_MALLOC_FAILURE); goto f_err; } BUF_reverse(gost_data, data, len); data = gost_data; } } #endif if (ispss) { if (EVP_PKEY_CTX_set_rsa_padding(pctx, RSA_PKCS1_PSS_PADDING) <= 0 /* -1 here means set saltlen to the digest len */ || EVP_PKEY_CTX_set_rsa_pss_saltlen(pctx, -1) <= 0) { SSLerr(SSL_F_TLS_PROCESS_CERT_VERIFY, ERR_R_EVP_LIB); goto f_err; } } else if (s->version == SSL3_VERSION && !EVP_MD_CTX_ctrl(mctx, EVP_CTRL_SSL3_MASTER_SECRET, (int)s->session->master_key_length, s->session->master_key)) { SSLerr(SSL_F_TLS_PROCESS_CERT_VERIFY, ERR_R_EVP_LIB); goto f_err; } if (EVP_DigestVerifyFinal(mctx, data, len) <= 0) { al = SSL_AD_DECRYPT_ERROR; SSLerr(SSL_F_TLS_PROCESS_CERT_VERIFY, SSL_R_BAD_SIGNATURE); goto f_err; } if (SSL_IS_TLS13(s)) ret = MSG_PROCESS_CONTINUE_READING; else ret = MSG_PROCESS_CONTINUE_PROCESSING; if (0) { f_err: ssl3_send_alert(s, SSL3_AL_FATAL, al); ossl_statem_set_error(s); } BIO_free(s->s3->handshake_buffer); s->s3->handshake_buffer = NULL; EVP_MD_CTX_free(mctx); #ifndef OPENSSL_NO_GOST OPENSSL_free(gost_data); #endif return ret; } int tls_construct_finished(SSL *s, WPACKET *pkt) { size_t finish_md_len; const char *sender; size_t slen; if (s->server) { sender = s->method->ssl3_enc->server_finished_label; slen = s->method->ssl3_enc->server_finished_label_len; } else { sender = s->method->ssl3_enc->client_finished_label; slen = s->method->ssl3_enc->client_finished_label_len; } finish_md_len = s->method->ssl3_enc->final_finish_mac(s, sender, slen, s->s3->tmp.finish_md); if (finish_md_len == 0) { SSLerr(SSL_F_TLS_CONSTRUCT_FINISHED, ERR_R_INTERNAL_ERROR); goto err; } s->s3->tmp.finish_md_len = finish_md_len; if (!WPACKET_memcpy(pkt, s->s3->tmp.finish_md, finish_md_len)) { SSLerr(SSL_F_TLS_CONSTRUCT_FINISHED, ERR_R_INTERNAL_ERROR); goto err; } /* Log the master secret, if logging is enabled. */ if (!ssl_log_master_secret(s, s->s3->client_random, SSL3_RANDOM_SIZE, s->session->master_key, s->session->master_key_length)) return 0; /* * Copy the finished so we can use it for renegotiation checks */ if (!s->server) { OPENSSL_assert(finish_md_len <= EVP_MAX_MD_SIZE); memcpy(s->s3->previous_client_finished, s->s3->tmp.finish_md, finish_md_len); s->s3->previous_client_finished_len = finish_md_len; } else { OPENSSL_assert(finish_md_len <= EVP_MAX_MD_SIZE); memcpy(s->s3->previous_server_finished, s->s3->tmp.finish_md, finish_md_len); s->s3->previous_server_finished_len = finish_md_len; } return 1; err: ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR); return 0; } #ifndef OPENSSL_NO_NEXTPROTONEG /* * ssl3_take_mac calculates the Finished MAC for the handshakes messages seen * to far. */ static void ssl3_take_mac(SSL *s) { const char *sender; size_t slen; /* * If no new cipher setup return immediately: other functions will set * the appropriate error. */ if (s->s3->tmp.new_cipher == NULL) return; if (!s->server) { sender = s->method->ssl3_enc->server_finished_label; slen = s->method->ssl3_enc->server_finished_label_len; } else { sender = s->method->ssl3_enc->client_finished_label; slen = s->method->ssl3_enc->client_finished_label_len; } s->s3->tmp.peer_finish_md_len = s->method->ssl3_enc->final_finish_mac(s, sender, slen, s->s3->tmp.peer_finish_md); } #endif MSG_PROCESS_RETURN tls_process_change_cipher_spec(SSL *s, PACKET *pkt) { int al; size_t remain; remain = PACKET_remaining(pkt); /* * 'Change Cipher Spec' is just a single byte, which should already have * been consumed by ssl_get_message() so there should be no bytes left, * unless we're using DTLS1_BAD_VER, which has an extra 2 bytes */ if (SSL_IS_DTLS(s)) { if ((s->version == DTLS1_BAD_VER && remain != DTLS1_CCS_HEADER_LENGTH + 1) || (s->version != DTLS1_BAD_VER && remain != DTLS1_CCS_HEADER_LENGTH - 1)) { al = SSL_AD_ILLEGAL_PARAMETER; SSLerr(SSL_F_TLS_PROCESS_CHANGE_CIPHER_SPEC, SSL_R_BAD_CHANGE_CIPHER_SPEC); goto f_err; } } else { if (remain != 0) { al = SSL_AD_ILLEGAL_PARAMETER; SSLerr(SSL_F_TLS_PROCESS_CHANGE_CIPHER_SPEC, SSL_R_BAD_CHANGE_CIPHER_SPEC); goto f_err; } } /* Check we have a cipher to change to */ if (s->s3->tmp.new_cipher == NULL) { al = SSL_AD_UNEXPECTED_MESSAGE; SSLerr(SSL_F_TLS_PROCESS_CHANGE_CIPHER_SPEC, SSL_R_CCS_RECEIVED_EARLY); goto f_err; } s->s3->change_cipher_spec = 1; if (!ssl3_do_change_cipher_spec(s)) { al = SSL_AD_INTERNAL_ERROR; SSLerr(SSL_F_TLS_PROCESS_CHANGE_CIPHER_SPEC, ERR_R_INTERNAL_ERROR); goto f_err; } if (SSL_IS_DTLS(s)) { dtls1_reset_seq_numbers(s, SSL3_CC_READ); if (s->version == DTLS1_BAD_VER) s->d1->handshake_read_seq++; #ifndef OPENSSL_NO_SCTP /* * Remember that a CCS has been received, so that an old key of * SCTP-Auth can be deleted when a CCS is sent. Will be ignored if no * SCTP is used */ BIO_ctrl(SSL_get_wbio(s), BIO_CTRL_DGRAM_SCTP_AUTH_CCS_RCVD, 1, NULL); #endif } return MSG_PROCESS_CONTINUE_READING; f_err: ssl3_send_alert(s, SSL3_AL_FATAL, al); ossl_statem_set_error(s); return MSG_PROCESS_ERROR; } MSG_PROCESS_RETURN tls_process_finished(SSL *s, PACKET *pkt) { int al = SSL_AD_INTERNAL_ERROR; size_t md_len; /* If this occurs, we have missed a message */ if (!SSL_IS_TLS13(s) && !s->s3->change_cipher_spec) { al = SSL_AD_UNEXPECTED_MESSAGE; SSLerr(SSL_F_TLS_PROCESS_FINISHED, SSL_R_GOT_A_FIN_BEFORE_A_CCS); goto f_err; } s->s3->change_cipher_spec = 0; md_len = s->s3->tmp.peer_finish_md_len; if (md_len != PACKET_remaining(pkt)) { al = SSL_AD_DECODE_ERROR; SSLerr(SSL_F_TLS_PROCESS_FINISHED, SSL_R_BAD_DIGEST_LENGTH); goto f_err; } if (CRYPTO_memcmp(PACKET_data(pkt), s->s3->tmp.peer_finish_md, md_len) != 0) { al = SSL_AD_DECRYPT_ERROR; SSLerr(SSL_F_TLS_PROCESS_FINISHED, SSL_R_DIGEST_CHECK_FAILED); goto f_err; } /* * Copy the finished so we can use it for renegotiation checks */ if (s->server) { OPENSSL_assert(md_len <= EVP_MAX_MD_SIZE); memcpy(s->s3->previous_client_finished, s->s3->tmp.peer_finish_md, md_len); s->s3->previous_client_finished_len = md_len; } else { OPENSSL_assert(md_len <= EVP_MAX_MD_SIZE); memcpy(s->s3->previous_server_finished, s->s3->tmp.peer_finish_md, md_len); s->s3->previous_server_finished_len = md_len; } /* * In TLS1.3 we also have to change cipher state and do any final processing * of the initial server flight (if we are a client) */ if (SSL_IS_TLS13(s)) { if (s->server) { if (!s->method->ssl3_enc->change_cipher_state(s, SSL3_CC_APPLICATION | SSL3_CHANGE_CIPHER_SERVER_READ)) { SSLerr(SSL_F_TLS_PROCESS_FINISHED, SSL_R_CANNOT_CHANGE_CIPHER); goto f_err; } } else { if (!s->method->ssl3_enc->generate_master_secret(s, s->master_secret, s->handshake_secret, 0, &s->session->master_key_length)) { SSLerr(SSL_F_TLS_PROCESS_FINISHED, SSL_R_CANNOT_CHANGE_CIPHER); goto f_err; } if (!s->method->ssl3_enc->change_cipher_state(s, SSL3_CC_APPLICATION | SSL3_CHANGE_CIPHER_CLIENT_READ)) { SSLerr(SSL_F_TLS_PROCESS_FINISHED, SSL_R_CANNOT_CHANGE_CIPHER); goto f_err; } if (!tls_process_initial_server_flight(s, &al)) goto f_err; } } return MSG_PROCESS_FINISHED_READING; f_err: ssl3_send_alert(s, SSL3_AL_FATAL, al); ossl_statem_set_error(s); return MSG_PROCESS_ERROR; } int tls_construct_change_cipher_spec(SSL *s, WPACKET *pkt) { if (!WPACKET_put_bytes_u8(pkt, SSL3_MT_CCS)) { SSLerr(SSL_F_TLS_CONSTRUCT_CHANGE_CIPHER_SPEC, ERR_R_INTERNAL_ERROR); ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR); return 0; } return 1; } /* Add a certificate to the WPACKET */ static int ssl_add_cert_to_wpacket(SSL *s, WPACKET *pkt, X509 *x, int chain, int *al) { int len; unsigned char *outbytes; len = i2d_X509(x, NULL); if (len < 0) { SSLerr(SSL_F_SSL_ADD_CERT_TO_WPACKET, ERR_R_BUF_LIB); *al = SSL_AD_INTERNAL_ERROR; return 0; } if (!WPACKET_sub_allocate_bytes_u24(pkt, len, &outbytes) || i2d_X509(x, &outbytes) != len) { SSLerr(SSL_F_SSL_ADD_CERT_TO_WPACKET, ERR_R_INTERNAL_ERROR); *al = SSL_AD_INTERNAL_ERROR; return 0; } if (SSL_IS_TLS13(s) && !tls_construct_extensions(s, pkt, EXT_TLS1_3_CERTIFICATE, x, chain, al)) return 0; return 1; } /* Add certificate chain to provided WPACKET */ static int ssl_add_cert_chain(SSL *s, WPACKET *pkt, CERT_PKEY *cpk, int *al) { int i, chain_count; X509 *x; STACK_OF(X509) *extra_certs; STACK_OF(X509) *chain = NULL; X509_STORE *chain_store; int tmpal = SSL_AD_INTERNAL_ERROR; if (cpk == NULL || cpk->x509 == NULL) return 1; x = cpk->x509; /* * If we have a certificate specific chain use it, else use parent ctx. */ if (cpk->chain != NULL) extra_certs = cpk->chain; else extra_certs = s->ctx->extra_certs; if ((s->mode & SSL_MODE_NO_AUTO_CHAIN) || extra_certs) chain_store = NULL; else if (s->cert->chain_store) chain_store = s->cert->chain_store; else chain_store = s->ctx->cert_store; if (chain_store != NULL) { X509_STORE_CTX *xs_ctx = X509_STORE_CTX_new(); if (xs_ctx == NULL) { SSLerr(SSL_F_SSL_ADD_CERT_CHAIN, ERR_R_MALLOC_FAILURE); goto err; } if (!X509_STORE_CTX_init(xs_ctx, chain_store, x, NULL)) { X509_STORE_CTX_free(xs_ctx); SSLerr(SSL_F_SSL_ADD_CERT_CHAIN, ERR_R_X509_LIB); goto err; } /* * It is valid for the chain not to be complete (because normally we * don't include the root cert in the chain). Therefore we deliberately * ignore the error return from this call. We're not actually verifying * the cert - we're just building as much of the chain as we can */ (void)X509_verify_cert(xs_ctx); /* Don't leave errors in the queue */ ERR_clear_error(); chain = X509_STORE_CTX_get0_chain(xs_ctx); i = ssl_security_cert_chain(s, chain, NULL, 0); if (i != 1) { #if 0 /* Dummy error calls so mkerr generates them */ SSLerr(SSL_F_SSL_ADD_CERT_CHAIN, SSL_R_EE_KEY_TOO_SMALL); SSLerr(SSL_F_SSL_ADD_CERT_CHAIN, SSL_R_CA_KEY_TOO_SMALL); SSLerr(SSL_F_SSL_ADD_CERT_CHAIN, SSL_R_CA_MD_TOO_WEAK); #endif X509_STORE_CTX_free(xs_ctx); SSLerr(SSL_F_SSL_ADD_CERT_CHAIN, i); goto err; } chain_count = sk_X509_num(chain); for (i = 0; i < chain_count; i++) { x = sk_X509_value(chain, i); if (!ssl_add_cert_to_wpacket(s, pkt, x, i, &tmpal)) { X509_STORE_CTX_free(xs_ctx); goto err; } } X509_STORE_CTX_free(xs_ctx); } else { i = ssl_security_cert_chain(s, extra_certs, x, 0); if (i != 1) { SSLerr(SSL_F_SSL_ADD_CERT_CHAIN, i); goto err; } if (!ssl_add_cert_to_wpacket(s, pkt, x, 0, &tmpal)) goto err; for (i = 0; i < sk_X509_num(extra_certs); i++) { x = sk_X509_value(extra_certs, i); if (!ssl_add_cert_to_wpacket(s, pkt, x, i + 1, &tmpal)) goto err; } } return 1; err: *al = tmpal; return 0; } unsigned long ssl3_output_cert_chain(SSL *s, WPACKET *pkt, CERT_PKEY *cpk, int *al) { int tmpal = SSL_AD_INTERNAL_ERROR; if (!WPACKET_start_sub_packet_u24(pkt) || !ssl_add_cert_chain(s, pkt, cpk, &tmpal) || !WPACKET_close(pkt)) { SSLerr(SSL_F_SSL3_OUTPUT_CERT_CHAIN, ERR_R_INTERNAL_ERROR); *al = tmpal; return 0; } return 1; } /* * Tidy up after the end of a handshake. In the case of SCTP this may result * in NBIO events. If |clearbufs| is set then init_buf and the wbio buffer is * freed up as well. */ WORK_STATE tls_finish_handshake(SSL *s, WORK_STATE wst, int clearbufs) { void (*cb) (const SSL *ssl, int type, int val) = NULL; #ifndef OPENSSL_NO_SCTP if (SSL_IS_DTLS(s) && BIO_dgram_is_sctp(SSL_get_wbio(s))) { WORK_STATE ret; ret = dtls_wait_for_dry(s); if (ret != WORK_FINISHED_CONTINUE) return ret; } #endif if (clearbufs) { if (!SSL_IS_DTLS(s)) { /* * We don't do this in DTLS because we may still need the init_buf * in case there are any unexpected retransmits */ BUF_MEM_free(s->init_buf); s->init_buf = NULL; } ssl_free_wbio_buffer(s); s->init_num = 0; } if (s->statem.cleanuphand) { /* skipped if we just sent a HelloRequest */ s->renegotiate = 0; s->new_session = 0; s->statem.cleanuphand = 0; ssl3_cleanup_key_block(s); if (s->server) { ssl_update_cache(s, SSL_SESS_CACHE_SERVER); s->ctx->stats.sess_accept_good++; s->handshake_func = ossl_statem_accept; } else { ssl_update_cache(s, SSL_SESS_CACHE_CLIENT); if (s->hit) s->ctx->stats.sess_hit++; s->handshake_func = ossl_statem_connect; s->ctx->stats.sess_connect_good++; } if (s->info_callback != NULL) cb = s->info_callback; else if (s->ctx->info_callback != NULL) cb = s->ctx->info_callback; if (cb != NULL) cb(s, SSL_CB_HANDSHAKE_DONE, 1); if (SSL_IS_DTLS(s)) { /* done with handshaking */ s->d1->handshake_read_seq = 0; s->d1->handshake_write_seq = 0; s->d1->next_handshake_write_seq = 0; dtls1_clear_received_buffer(s); } } /* * If we've not cleared the buffers its because we've got more work to do, * so continue. */ if (!clearbufs) return WORK_FINISHED_CONTINUE; return WORK_FINISHED_STOP; } int tls_get_message_header(SSL *s, int *mt) { /* s->init_num < SSL3_HM_HEADER_LENGTH */ int skip_message, i, recvd_type, al; unsigned char *p; size_t l, readbytes; p = (unsigned char *)s->init_buf->data; do { while (s->init_num < SSL3_HM_HEADER_LENGTH) { i = s->method->ssl_read_bytes(s, SSL3_RT_HANDSHAKE, &recvd_type, &p[s->init_num], SSL3_HM_HEADER_LENGTH - s->init_num, 0, &readbytes); if (i <= 0) { s->rwstate = SSL_READING; return 0; } if (recvd_type == SSL3_RT_CHANGE_CIPHER_SPEC) { /* * A ChangeCipherSpec must be a single byte and may not occur * in the middle of a handshake message. */ if (s->init_num != 0 || readbytes != 1 || p[0] != SSL3_MT_CCS) { al = SSL_AD_UNEXPECTED_MESSAGE; SSLerr(SSL_F_TLS_GET_MESSAGE_HEADER, SSL_R_BAD_CHANGE_CIPHER_SPEC); goto f_err; } s->s3->tmp.message_type = *mt = SSL3_MT_CHANGE_CIPHER_SPEC; s->init_num = readbytes - 1; s->init_msg = s->init_buf->data; s->s3->tmp.message_size = readbytes; return 1; } else if (recvd_type != SSL3_RT_HANDSHAKE) { al = SSL_AD_UNEXPECTED_MESSAGE; SSLerr(SSL_F_TLS_GET_MESSAGE_HEADER, SSL_R_CCS_RECEIVED_EARLY); goto f_err; } s->init_num += readbytes; } skip_message = 0; if (!s->server) if (s->statem.hand_state != TLS_ST_OK && p[0] == SSL3_MT_HELLO_REQUEST) /* * The server may always send 'Hello Request' messages -- * we are doing a handshake anyway now, so ignore them if * their format is correct. Does not count for 'Finished' * MAC. */ if (p[1] == 0 && p[2] == 0 && p[3] == 0) { s->init_num = 0; skip_message = 1; if (s->msg_callback) s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE, p, SSL3_HM_HEADER_LENGTH, s, s->msg_callback_arg); } } while (skip_message); /* s->init_num == SSL3_HM_HEADER_LENGTH */ *mt = *p; s->s3->tmp.message_type = *(p++); if (RECORD_LAYER_is_sslv2_record(&s->rlayer)) { /* * Only happens with SSLv3+ in an SSLv2 backward compatible * ClientHello * * Total message size is the remaining record bytes to read * plus the SSL3_HM_HEADER_LENGTH bytes that we already read */ l = RECORD_LAYER_get_rrec_length(&s->rlayer) + SSL3_HM_HEADER_LENGTH; s->s3->tmp.message_size = l; s->init_msg = s->init_buf->data; s->init_num = SSL3_HM_HEADER_LENGTH; } else { n2l3(p, l); /* BUF_MEM_grow takes an 'int' parameter */ if (l > (INT_MAX - SSL3_HM_HEADER_LENGTH)) { al = SSL_AD_ILLEGAL_PARAMETER; SSLerr(SSL_F_TLS_GET_MESSAGE_HEADER, SSL_R_EXCESSIVE_MESSAGE_SIZE); goto f_err; } s->s3->tmp.message_size = l; s->init_msg = s->init_buf->data + SSL3_HM_HEADER_LENGTH; s->init_num = 0; } return 1; f_err: ssl3_send_alert(s, SSL3_AL_FATAL, al); return 0; } int tls_get_message_body(SSL *s, size_t *len) { size_t n, readbytes; unsigned char *p; int i; if (s->s3->tmp.message_type == SSL3_MT_CHANGE_CIPHER_SPEC) { /* We've already read everything in */ *len = (unsigned long)s->init_num; return 1; } p = s->init_msg; n = s->s3->tmp.message_size - s->init_num; while (n > 0) { i = s->method->ssl_read_bytes(s, SSL3_RT_HANDSHAKE, NULL, &p[s->init_num], n, 0, &readbytes); if (i <= 0) { s->rwstate = SSL_READING; *len = 0; return 0; } s->init_num += readbytes; n -= readbytes; } #ifndef OPENSSL_NO_NEXTPROTONEG /* * If receiving Finished, record MAC of prior handshake messages for * Finished verification. */ if (*s->init_buf->data == SSL3_MT_FINISHED) ssl3_take_mac(s); #endif /* Feed this message into MAC computation. */ if (RECORD_LAYER_is_sslv2_record(&s->rlayer)) { if (!ssl3_finish_mac(s, (unsigned char *)s->init_buf->data, s->init_num)) { SSLerr(SSL_F_TLS_GET_MESSAGE_BODY, ERR_R_EVP_LIB); ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR); *len = 0; return 0; } if (s->msg_callback) s->msg_callback(0, SSL2_VERSION, 0, s->init_buf->data, (size_t)s->init_num, s, s->msg_callback_arg); } else { if (!ssl3_finish_mac(s, (unsigned char *)s->init_buf->data, s->init_num + SSL3_HM_HEADER_LENGTH)) { SSLerr(SSL_F_TLS_GET_MESSAGE_BODY, ERR_R_EVP_LIB); ssl3_send_alert(s, SSL3_AL_FATAL, SSL_AD_INTERNAL_ERROR); *len = 0; return 0; } if (s->msg_callback) s->msg_callback(0, s->version, SSL3_RT_HANDSHAKE, s->init_buf->data, (size_t)s->init_num + SSL3_HM_HEADER_LENGTH, s, s->msg_callback_arg); } *len = s->init_num; return 1; } int ssl_cert_type(const X509 *x, const EVP_PKEY *pk) { if (pk == NULL && (pk = X509_get0_pubkey(x)) == NULL) return -1; switch (EVP_PKEY_id(pk)) { default: return -1; case EVP_PKEY_RSA: return SSL_PKEY_RSA_ENC; case EVP_PKEY_DSA: return SSL_PKEY_DSA_SIGN; #ifndef OPENSSL_NO_EC case EVP_PKEY_EC: return SSL_PKEY_ECC; #endif #ifndef OPENSSL_NO_GOST case NID_id_GostR3410_2001: return SSL_PKEY_GOST01; case NID_id_GostR3410_2012_256: return SSL_PKEY_GOST12_256; case NID_id_GostR3410_2012_512: return SSL_PKEY_GOST12_512; #endif } } int ssl_verify_alarm_type(long type) { int al; switch (type) { case X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT: case X509_V_ERR_UNABLE_TO_GET_CRL: case X509_V_ERR_UNABLE_TO_GET_CRL_ISSUER: al = SSL_AD_UNKNOWN_CA; break; case X509_V_ERR_UNABLE_TO_DECRYPT_CERT_SIGNATURE: case X509_V_ERR_UNABLE_TO_DECRYPT_CRL_SIGNATURE: case X509_V_ERR_UNABLE_TO_DECODE_ISSUER_PUBLIC_KEY: case X509_V_ERR_ERROR_IN_CERT_NOT_BEFORE_FIELD: case X509_V_ERR_ERROR_IN_CERT_NOT_AFTER_FIELD: case X509_V_ERR_ERROR_IN_CRL_LAST_UPDATE_FIELD: case X509_V_ERR_ERROR_IN_CRL_NEXT_UPDATE_FIELD: case X509_V_ERR_CERT_NOT_YET_VALID: case X509_V_ERR_CRL_NOT_YET_VALID: case X509_V_ERR_CERT_UNTRUSTED: case X509_V_ERR_CERT_REJECTED: case X509_V_ERR_HOSTNAME_MISMATCH: case X509_V_ERR_EMAIL_MISMATCH: case X509_V_ERR_IP_ADDRESS_MISMATCH: case X509_V_ERR_DANE_NO_MATCH: case X509_V_ERR_EE_KEY_TOO_SMALL: case X509_V_ERR_CA_KEY_TOO_SMALL: case X509_V_ERR_CA_MD_TOO_WEAK: al = SSL_AD_BAD_CERTIFICATE; break; case X509_V_ERR_CERT_SIGNATURE_FAILURE: case X509_V_ERR_CRL_SIGNATURE_FAILURE: al = SSL_AD_DECRYPT_ERROR; break; case X509_V_ERR_CERT_HAS_EXPIRED: case X509_V_ERR_CRL_HAS_EXPIRED: al = SSL_AD_CERTIFICATE_EXPIRED; break; case X509_V_ERR_CERT_REVOKED: al = SSL_AD_CERTIFICATE_REVOKED; break; case X509_V_ERR_UNSPECIFIED: case X509_V_ERR_OUT_OF_MEM: case X509_V_ERR_INVALID_CALL: case X509_V_ERR_STORE_LOOKUP: al = SSL_AD_INTERNAL_ERROR; break; case X509_V_ERR_DEPTH_ZERO_SELF_SIGNED_CERT: case X509_V_ERR_SELF_SIGNED_CERT_IN_CHAIN: case X509_V_ERR_UNABLE_TO_GET_ISSUER_CERT_LOCALLY: case X509_V_ERR_UNABLE_TO_VERIFY_LEAF_SIGNATURE: case X509_V_ERR_CERT_CHAIN_TOO_LONG: case X509_V_ERR_PATH_LENGTH_EXCEEDED: case X509_V_ERR_INVALID_CA: al = SSL_AD_UNKNOWN_CA; break; case X509_V_ERR_APPLICATION_VERIFICATION: al = SSL_AD_HANDSHAKE_FAILURE; break; case X509_V_ERR_INVALID_PURPOSE: al = SSL_AD_UNSUPPORTED_CERTIFICATE; break; default: al = SSL_AD_CERTIFICATE_UNKNOWN; break; } return (al); } int ssl_allow_compression(SSL *s) { if (s->options & SSL_OP_NO_COMPRESSION) return 0; return ssl_security(s, SSL_SECOP_COMPRESSION, 0, 0, NULL); } static int version_cmp(const SSL *s, int a, int b) { int dtls = SSL_IS_DTLS(s); if (a == b) return 0; if (!dtls) return a < b ? -1 : 1; return DTLS_VERSION_LT(a, b) ? -1 : 1; } typedef struct { int version; const SSL_METHOD *(*cmeth) (void); const SSL_METHOD *(*smeth) (void); } version_info; #if TLS_MAX_VERSION != TLS1_3_VERSION # error Code needs update for TLS_method() support beyond TLS1_3_VERSION. #endif static const version_info tls_version_table[] = { #ifndef OPENSSL_NO_TLS1_3 {TLS1_3_VERSION, tlsv1_3_client_method, tlsv1_3_server_method}, #else {TLS1_3_VERSION, NULL, NULL}, #endif #ifndef OPENSSL_NO_TLS1_2 {TLS1_2_VERSION, tlsv1_2_client_method, tlsv1_2_server_method}, #else {TLS1_2_VERSION, NULL, NULL}, #endif #ifndef OPENSSL_NO_TLS1_1 {TLS1_1_VERSION, tlsv1_1_client_method, tlsv1_1_server_method}, #else {TLS1_1_VERSION, NULL, NULL}, #endif #ifndef OPENSSL_NO_TLS1 {TLS1_VERSION, tlsv1_client_method, tlsv1_server_method}, #else {TLS1_VERSION, NULL, NULL}, #endif #ifndef OPENSSL_NO_SSL3 {SSL3_VERSION, sslv3_client_method, sslv3_server_method}, #else {SSL3_VERSION, NULL, NULL}, #endif {0, NULL, NULL}, }; #if DTLS_MAX_VERSION != DTLS1_2_VERSION # error Code needs update for DTLS_method() support beyond DTLS1_2_VERSION. #endif static const version_info dtls_version_table[] = { #ifndef OPENSSL_NO_DTLS1_2 {DTLS1_2_VERSION, dtlsv1_2_client_method, dtlsv1_2_server_method}, #else {DTLS1_2_VERSION, NULL, NULL}, #endif #ifndef OPENSSL_NO_DTLS1 {DTLS1_VERSION, dtlsv1_client_method, dtlsv1_server_method}, {DTLS1_BAD_VER, dtls_bad_ver_client_method, NULL}, #else {DTLS1_VERSION, NULL, NULL}, {DTLS1_BAD_VER, NULL, NULL}, #endif {0, NULL, NULL}, }; /* * ssl_method_error - Check whether an SSL_METHOD is enabled. * * @s: The SSL handle for the candidate method * @method: the intended method. * * Returns 0 on success, or an SSL error reason on failure. */ static int ssl_method_error(const SSL *s, const SSL_METHOD *method) { int version = method->version; if ((s->min_proto_version != 0 && version_cmp(s, version, s->min_proto_version) < 0) || ssl_security(s, SSL_SECOP_VERSION, 0, version, NULL) == 0) return SSL_R_VERSION_TOO_LOW; if (s->max_proto_version != 0 && version_cmp(s, version, s->max_proto_version) > 0) return SSL_R_VERSION_TOO_HIGH; if ((s->options & method->mask) != 0) return SSL_R_UNSUPPORTED_PROTOCOL; if ((method->flags & SSL_METHOD_NO_SUITEB) != 0 && tls1_suiteb(s)) return SSL_R_AT_LEAST_TLS_1_2_NEEDED_IN_SUITEB_MODE; else if ((method->flags & SSL_METHOD_NO_FIPS) != 0 && FIPS_mode()) return SSL_R_AT_LEAST_TLS_1_0_NEEDED_IN_FIPS_MODE; return 0; } /* * ssl_version_supported - Check that the specified `version` is supported by * `SSL *` instance * * @s: The SSL handle for the candidate method * @version: Protocol version to test against * * Returns 1 when supported, otherwise 0 */ int ssl_version_supported(const SSL *s, int version) { const version_info *vent; const version_info *table; switch (s->method->version) { default: /* Version should match method version for non-ANY method */ return version_cmp(s, version, s->version) == 0; case TLS_ANY_VERSION: table = tls_version_table; break; case DTLS_ANY_VERSION: table = dtls_version_table; break; } for (vent = table; vent->version != 0 && version_cmp(s, version, vent->version) <= 0; ++vent) { if (vent->cmeth != NULL && version_cmp(s, version, vent->version) == 0 && ssl_method_error(s, vent->cmeth()) == 0) { return 1; } } return 0; } /* * ssl_check_version_downgrade - In response to RFC7507 SCSV version * fallback indication from a client check whether we're using the highest * supported protocol version. * * @s server SSL handle. * * Returns 1 when using the highest enabled version, 0 otherwise. */ int ssl_check_version_downgrade(SSL *s) { const version_info *vent; const version_info *table; /* * Check that the current protocol is the highest enabled version * (according to s->ctx->method, as version negotiation may have changed * s->method). */ if (s->version == s->ctx->method->version) return 1; /* * Apparently we're using a version-flexible SSL_METHOD (not at its * highest protocol version). */ if (s->ctx->method->version == TLS_method()->version) table = tls_version_table; else if (s->ctx->method->version == DTLS_method()->version) table = dtls_version_table; else { /* Unexpected state; fail closed. */ return 0; } for (vent = table; vent->version != 0; ++vent) { if (vent->smeth != NULL && ssl_method_error(s, vent->smeth()) == 0) return s->version == vent->version; } return 0; } /* * ssl_set_version_bound - set an upper or lower bound on the supported (D)TLS * protocols, provided the initial (D)TLS method is version-flexible. This * function sanity-checks the proposed value and makes sure the method is * version-flexible, then sets the limit if all is well. * * @method_version: The version of the current SSL_METHOD. * @version: the intended limit. * @bound: pointer to limit to be updated. * * Returns 1 on success, 0 on failure. */ int ssl_set_version_bound(int method_version, int version, int *bound) { if (version == 0) { *bound = version; return 1; } /*- * Restrict TLS methods to TLS protocol versions. * Restrict DTLS methods to DTLS protocol versions. * Note, DTLS version numbers are decreasing, use comparison macros. * * Note that for both lower-bounds we use explicit versions, not * (D)TLS_MIN_VERSION. This is because we don't want to break user * configurations. If the MIN (supported) version ever rises, the user's * "floor" remains valid even if no longer available. We don't expect the * MAX ceiling to ever get lower, so making that variable makes sense. */ switch (method_version) { default: /* * XXX For fixed version methods, should we always fail and not set any * bounds, always succeed and not set any bounds, or set the bounds and * arrange to fail later if they are not met? At present fixed-version * methods are not subject to controls that disable individual protocol * versions. */ return 0; case TLS_ANY_VERSION: if (version < SSL3_VERSION || version > TLS_MAX_VERSION) return 0; break; case DTLS_ANY_VERSION: if (DTLS_VERSION_GT(version, DTLS_MAX_VERSION) || DTLS_VERSION_LT(version, DTLS1_BAD_VER)) return 0; break; } *bound = version; return 1; } /* * ssl_choose_server_version - Choose server (D)TLS version. Called when the * client HELLO is received to select the final server protocol version and * the version specific method. * * @s: server SSL handle. * * Returns 0 on success or an SSL error reason number on failure. */ int ssl_choose_server_version(SSL *s, CLIENTHELLO_MSG *hello) { /*- * With version-flexible methods we have an initial state with: * * s->method->version == (D)TLS_ANY_VERSION, * s->version == (D)TLS_MAX_VERSION. * * So we detect version-flexible methods via the method version, not the * handle version. */ int server_version = s->method->version; int client_version = hello->legacy_version; const version_info *vent; const version_info *table; int disabled = 0; RAW_EXTENSION *suppversions; s->client_version = client_version; switch (server_version) { default: /* * TODO(TLS1.3): This check will fail if someone attempts to do * renegotiation in TLS1.3 at the moment. We need to ensure we disable * renegotiation for TLS1.3 */ if (version_cmp(s, client_version, s->version) < 0) return SSL_R_WRONG_SSL_VERSION; /* * If this SSL handle is not from a version flexible method we don't * (and never did) check min/max FIPS or Suite B constraints. Hope * that's OK. It is up to the caller to not choose fixed protocol * versions they don't want. If not, then easy to fix, just return * ssl_method_error(s, s->method) */ return 0; case TLS_ANY_VERSION: table = tls_version_table; break; case DTLS_ANY_VERSION: table = dtls_version_table; break; } suppversions = &hello->pre_proc_exts[TLSEXT_IDX_supported_versions]; if (suppversions->present && !SSL_IS_DTLS(s)) { unsigned int candidate_vers = 0; unsigned int best_vers = 0; const SSL_METHOD *best_method = NULL; PACKET versionslist; suppversions->parsed = 1; if (!PACKET_as_length_prefixed_1(&suppversions->data, &versionslist)) { /* Trailing or invalid data? */ return SSL_R_LENGTH_MISMATCH; } while (PACKET_get_net_2(&versionslist, &candidate_vers)) { /* TODO(TLS1.3): Remove this before release */ if (candidate_vers == TLS1_3_VERSION_DRAFT) candidate_vers = TLS1_3_VERSION; /* * TODO(TLS1.3): There is some discussion on the TLS list about * wheter to ignore versions version != 0 && vent->version != (int)candidate_vers; ++vent) continue; if (vent->version != 0 && vent->smeth != NULL) { const SSL_METHOD *method; method = vent->smeth(); if (ssl_method_error(s, method) == 0) { best_vers = candidate_vers; best_method = method; } } } if (PACKET_remaining(&versionslist) != 0) { /* Trailing data? */ return SSL_R_LENGTH_MISMATCH; } if (best_vers > 0) { s->version = best_vers; s->method = best_method; return 0; } return SSL_R_UNSUPPORTED_PROTOCOL; } /* * If the supported versions extension isn't present, then the highest * version we can negotiate is TLSv1.2 */ if (version_cmp(s, client_version, TLS1_3_VERSION) >= 0) client_version = TLS1_2_VERSION; /* * No supported versions extension, so we just use the version supplied in * the ClientHello. */ for (vent = table; vent->version != 0; ++vent) { const SSL_METHOD *method; if (vent->smeth == NULL || version_cmp(s, client_version, vent->version) < 0) continue; method = vent->smeth(); if (ssl_method_error(s, method) == 0) { s->version = vent->version; s->method = method; return 0; } disabled = 1; } return disabled ? SSL_R_UNSUPPORTED_PROTOCOL : SSL_R_VERSION_TOO_LOW; } /* * ssl_choose_client_version - Choose client (D)TLS version. Called when the * server HELLO is received to select the final client protocol version and * the version specific method. * * @s: client SSL handle. * @version: The proposed version from the server's HELLO. * * Returns 0 on success or an SSL error reason number on failure. */ int ssl_choose_client_version(SSL *s, int version) { const version_info *vent; const version_info *table; /* TODO(TLS1.3): Remove this before release */ if (version == TLS1_3_VERSION_DRAFT) version = TLS1_3_VERSION; switch (s->method->version) { default: if (version != s->version) return SSL_R_WRONG_SSL_VERSION; /* * If this SSL handle is not from a version flexible method we don't * (and never did) check min/max, FIPS or Suite B constraints. Hope * that's OK. It is up to the caller to not choose fixed protocol * versions they don't want. If not, then easy to fix, just return * ssl_method_error(s, s->method) */ return 0; case TLS_ANY_VERSION: table = tls_version_table; break; case DTLS_ANY_VERSION: table = dtls_version_table; break; } for (vent = table; vent->version != 0; ++vent) { const SSL_METHOD *method; int err; if (version != vent->version) continue; if (vent->cmeth == NULL) break; method = vent->cmeth(); err = ssl_method_error(s, method); if (err != 0) return err; s->method = method; s->version = version; return 0; } return SSL_R_UNSUPPORTED_PROTOCOL; } /* * ssl_get_client_min_max_version - get minimum and maximum client version * @s: The SSL connection * @min_version: The minimum supported version * @max_version: The maximum supported version * * Work out what version we should be using for the initial ClientHello if the * version is initially (D)TLS_ANY_VERSION. We apply any explicit SSL_OP_NO_xxx * options, the MinProtocol and MaxProtocol configuration commands, any Suite B * or FIPS_mode() constraints and any floor imposed by the security level here, * so we don't advertise the wrong protocol version to only reject the outcome later. * * Computing the right floor matters. If, e.g., TLS 1.0 and 1.2 are enabled, * TLS 1.1 is disabled, but the security level, Suite-B and/or MinProtocol * only allow TLS 1.2, we want to advertise TLS1.2, *not* TLS1. * * Returns 0 on success or an SSL error reason number on failure. On failure * min_version and max_version will also be set to 0. */ int ssl_get_client_min_max_version(const SSL *s, int *min_version, int *max_version) { int version; int hole; const SSL_METHOD *single = NULL; const SSL_METHOD *method; const version_info *table; const version_info *vent; switch (s->method->version) { default: /* * If this SSL handle is not from a version flexible method we don't * (and never did) check min/max FIPS or Suite B constraints. Hope * that's OK. It is up to the caller to not choose fixed protocol * versions they don't want. If not, then easy to fix, just return * ssl_method_error(s, s->method) */ *min_version = *max_version = s->version; return 0; case TLS_ANY_VERSION: table = tls_version_table; break; case DTLS_ANY_VERSION: table = dtls_version_table; break; } /* * SSL_OP_NO_X disables all protocols above X *if* there are some protocols * below X enabled. This is required in order to maintain the "version * capability" vector contiguous. Any versions with a NULL client method * (protocol version client is disabled at compile-time) is also a "hole". * * Our initial state is hole == 1, version == 0. That is, versions above * the first version in the method table are disabled (a "hole" above * the valid protocol entries) and we don't have a selected version yet. * * Whenever "hole == 1", and we hit an enabled method, its version becomes * the selected version, and the method becomes a candidate "single" * method. We're no longer in a hole, so "hole" becomes 0. * * If "hole == 0" and we hit an enabled method, then "single" is cleared, * as we support a contiguous range of at least two methods. If we hit * a disabled method, then hole becomes true again, but nothing else * changes yet, because all the remaining methods may be disabled too. * If we again hit an enabled method after the new hole, it becomes * selected, as we start from scratch. */ *min_version = version = 0; hole = 1; for (vent = table; vent->version != 0; ++vent) { /* * A table entry with a NULL client method is still a hole in the * "version capability" vector. */ if (vent->cmeth == NULL) { hole = 1; continue; } method = vent->cmeth(); if (ssl_method_error(s, method) != 0) { hole = 1; } else if (!hole) { single = NULL; *min_version = method->version; } else { version = (single = method)->version; *min_version = version; hole = 0; } } *max_version = version; /* Fail if everything is disabled */ if (version == 0) return SSL_R_NO_PROTOCOLS_AVAILABLE; return 0; } /* * ssl_set_client_hello_version - Work out what version we should be using for * the initial ClientHello.legacy_version field. * * @s: client SSL handle. * * Returns 0 on success or an SSL error reason number on failure. */ int ssl_set_client_hello_version(SSL *s) { int ver_min, ver_max, ret; ret = ssl_get_client_min_max_version(s, &ver_min, &ver_max); if (ret != 0) return ret; s->version = ver_max; /* TLS1.3 always uses TLS1.2 in the legacy_version field */ if (!SSL_IS_DTLS(s) && ver_max > TLS1_2_VERSION) ver_max = TLS1_2_VERSION; s->client_version = ver_max; return 0; }