/* * Copyright 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 */ #include "../ssl_locl.h" #include "statem_locl.h" static int tls_ext_final_renegotiate(SSL *s, unsigned int context, int sent, int *al); static int tls_ext_init_server_name(SSL *s, unsigned int context); static int tls_ext_final_server_name(SSL *s, unsigned int context, int sent, int *al); #ifndef OPENSSL_NO_EC static int tls_ext_final_ec_pt_formats(SSL *s, unsigned int context, int sent, int *al); #endif static int tls_ext_init_session_ticket(SSL *s, unsigned int context); static int tls_ext_init_status_request(SSL *s, unsigned int context); static int tls_ext_final_status_request(SSL *s, unsigned int context, int sent, int *al); #ifndef OPENSSL_NO_NEXTPROTONEG static int tls_ext_init_npn(SSL *s, unsigned int context); #endif static int tls_ext_init_alpn(SSL *s, unsigned int context); static int tls_ext_final_alpn(SSL *s, unsigned int context, int sent, int *al); static int tls_ext_init_sig_algs(SSL *s, unsigned int context); #ifndef OPENSSL_NO_SRP static int tls_ext_init_srp(SSL *s, unsigned int context); #endif static int tls_ext_init_etm(SSL *s, unsigned int context); static int tls_ext_init_ems(SSL *s, unsigned int context); static int tls_ext_final_ems(SSL *s, unsigned int context, int sent, int *al); #ifndef OPENSSL_NO_SRTP static int tls_ext_init_srtp(SSL *s, unsigned int context); #endif /* Structure to define a built-in extension */ typedef struct { /* The ID for the extension */ unsigned int type; /* * Initialise extension before parsing. Always called for relevant contexts * even if extension not present */ int (*init_ext)(SSL *s, unsigned int context); /* Parse extension received by server from client */ int (*parse_client_ext)(SSL *s, PACKET *pkt, int *al); /* Parse extension received by client from server */ int (*parse_server_ext)(SSL *s, PACKET *pkt, int *al); /* Construct extension sent by server */ int (*construct_server_ext)(SSL *s, WPACKET *pkt, int *al); /* Construct extension sent by client */ int (*construct_client_ext)(SSL *s, WPACKET *pkt, int *al); /* * Finalise extension after parsing. Always called where an extensions was * initialised even if the extension was not present. |sent| is set to 1 if * the extension was seen, or 0 otherwise. */ int (*finalise_ext)(SSL *s, unsigned int context, int sent, int *al); unsigned int context; } EXTENSION_DEFINITION; /* * Definitions of all built-in extensions. NOTE: Changes in the number or order * of these extensions should be mirrored with equivalent changes to the indexes * defined in statem_locl.h. * Each extension has an initialiser, a client and * server side parser and a finaliser. The initialiser is called (if the * extension is relevant to the given context) even if we did not see the * extension in the message that we received. The parser functions are only * called if we see the extension in the message. The finalisers are always * called if the initialiser was called. * There are also server and client side constructor functions which are always * called during message construction if the extension is relevant for the * given context. * The initialisation, parsing, finalisation and construction functions are * always called in the order defined in this list. Some extensions may depend * on others having been processed first, so the order of this list is * significant. * The extension context is defined by a series of flags which specify which * messages the extension is relevant to. These flags also specify whether the * extension is relevant to a paricular protocol or protocol version. * * TODO(TLS1.3): Make sure we have a test to check the consistency of these */ static const EXTENSION_DEFINITION ext_defs[] = { { TLSEXT_TYPE_renegotiate, NULL, tls_parse_client_renegotiate, tls_parse_server_renegotiate, tls_construct_server_renegotiate, tls_construct_client_renegotiate, tls_ext_final_renegotiate, EXT_CLIENT_HELLO | EXT_TLS1_2_SERVER_HELLO | EXT_SSL3_ALLOWED | EXT_TLS1_2_AND_BELOW_ONLY }, { TLSEXT_TYPE_server_name, tls_ext_init_server_name, tls_parse_client_server_name, tls_parse_server_server_name, tls_construct_server_server_name, tls_construct_client_server_name, tls_ext_final_server_name, EXT_CLIENT_HELLO | EXT_TLS1_2_SERVER_HELLO | EXT_TLS1_3_ENCRYPTED_EXTENSIONS }, #ifndef OPENSSL_NO_SRP { TLSEXT_TYPE_srp, tls_ext_init_srp, tls_parse_client_srp, NULL, NULL, tls_construct_client_srp, NULL, EXT_CLIENT_HELLO | EXT_TLS1_2_AND_BELOW_ONLY }, #endif #ifndef OPENSSL_NO_EC { TLSEXT_TYPE_ec_point_formats, NULL, tls_parse_client_ec_pt_formats, tls_parse_server_ec_pt_formats, tls_construct_server_ec_pt_formats, tls_construct_client_ec_pt_formats, tls_ext_final_ec_pt_formats, EXT_CLIENT_HELLO | EXT_TLS1_2_AND_BELOW_ONLY }, { TLSEXT_TYPE_supported_groups, NULL, tls_parse_client_supported_groups, NULL, NULL /* TODO(TLS1.3): Need to add this */, tls_construct_client_supported_groups, NULL, EXT_CLIENT_HELLO | EXT_TLS1_3_ENCRYPTED_EXTENSIONS }, #endif { TLSEXT_TYPE_session_ticket, tls_ext_init_session_ticket, tls_parse_client_session_ticket, tls_parse_server_session_ticket, tls_construct_server_session_ticket, tls_construct_client_session_ticket, NULL, EXT_CLIENT_HELLO | EXT_TLS1_2_SERVER_HELLO | EXT_TLS1_2_AND_BELOW_ONLY }, { TLSEXT_TYPE_signature_algorithms, tls_ext_init_sig_algs, tls_parse_client_sig_algs, NULL, NULL, tls_construct_client_sig_algs, NULL, EXT_CLIENT_HELLO }, #ifndef OPENSSL_NO_OCSP { TLSEXT_TYPE_status_request, tls_ext_init_status_request, tls_parse_client_status_request, tls_parse_server_status_request, tls_construct_server_status_request, tls_construct_client_status_request, tls_ext_final_status_request, EXT_CLIENT_HELLO | EXT_TLS1_2_SERVER_HELLO | EXT_TLS1_3_CERTIFICATE }, #endif #ifndef OPENSSL_NO_NEXTPROTONEG { TLSEXT_TYPE_next_proto_neg, tls_ext_init_npn, tls_parse_client_npn, tls_parse_server_npn, tls_construct_server_next_proto_neg, tls_construct_client_npn, NULL, EXT_CLIENT_HELLO | EXT_TLS1_2_SERVER_HELLO | EXT_TLS1_2_AND_BELOW_ONLY }, #endif { /* * Must appear in this list after server_name so that finalisation * happens after server_name callbacks */ TLSEXT_TYPE_application_layer_protocol_negotiation, tls_ext_init_alpn, tls_parse_client_alpn, tls_parse_server_alpn, tls_construct_server_alpn, tls_construct_client_alpn, tls_ext_final_alpn, EXT_CLIENT_HELLO | EXT_TLS1_2_SERVER_HELLO | EXT_TLS1_3_ENCRYPTED_EXTENSIONS }, #ifndef OPENSSL_NO_SRTP { TLSEXT_TYPE_use_srtp, tls_ext_init_srtp, tls_parse_client_use_srtp, tls_parse_server_use_srtp, tls_construct_server_use_srtp, tls_construct_client_use_srtp, NULL, EXT_CLIENT_HELLO | EXT_TLS1_2_SERVER_HELLO | EXT_TLS1_3_ENCRYPTED_EXTENSIONS | EXT_DTLS_ONLY }, #endif { TLSEXT_TYPE_encrypt_then_mac, tls_ext_init_etm, tls_parse_client_etm, tls_parse_server_etm, tls_construct_server_etm, tls_construct_client_etm, NULL, EXT_CLIENT_HELLO | EXT_TLS1_2_SERVER_HELLO | EXT_TLS1_2_AND_BELOW_ONLY }, #ifndef OPENSSL_NO_CT { TLSEXT_TYPE_signed_certificate_timestamp, NULL, /* * No server side support for this, but can be provided by a custom * extension. This is an exception to the rule that custom extensions * cannot override built in ones. */ NULL, tls_parse_server_sct, NULL, tls_construct_client_sct, NULL, EXT_CLIENT_HELLO | EXT_TLS1_2_SERVER_HELLO | EXT_TLS1_3_CERTIFICATE }, #endif { TLSEXT_TYPE_extended_master_secret, tls_ext_init_ems, tls_parse_client_ems, tls_parse_server_ems, tls_construct_server_ems, tls_construct_client_ems, tls_ext_final_ems, EXT_CLIENT_HELLO | EXT_TLS1_2_SERVER_HELLO | EXT_TLS1_2_AND_BELOW_ONLY }, { TLSEXT_TYPE_supported_versions, NULL, /* Processed inline as part of version selection */ NULL, NULL, NULL, tls_construct_client_supported_versions, NULL, EXT_CLIENT_HELLO | EXT_TLS_IMPLEMENTATION_ONLY | EXT_TLS1_3_ONLY }, { /* * Must be in this list after supported_groups. We need that to have * been parsed before we do this one. */ TLSEXT_TYPE_key_share, NULL, tls_parse_client_key_share, tls_parse_server_key_share, tls_construct_server_key_share, tls_construct_client_key_share, NULL, EXT_CLIENT_HELLO | EXT_TLS1_3_SERVER_HELLO | EXT_TLS1_3_HELLO_RETRY_REQUEST | EXT_TLS_IMPLEMENTATION_ONLY | EXT_TLS1_3_ONLY }, { /* * Special unsolicited ServerHello extension only used when * SSL_OP_CRYPTOPRO_TLSEXT_BUG is set */ TLSEXT_TYPE_cryptopro_bug, NULL, NULL, NULL, tls_construct_server_cryptopro_bug, NULL, NULL, EXT_TLS1_2_SERVER_HELLO | EXT_TLS1_2_AND_BELOW_ONLY }, { /* Last in the list because it must be added as the last extension */ TLSEXT_TYPE_padding, NULL, /* We send this, but don't read it */ NULL, NULL, NULL, tls_construct_client_padding, NULL, EXT_CLIENT_HELLO } }; /* * Verify whether we are allowed to use the extension |type| in the current * |context|. Returns 1 to indicate the extension is allowed or unknown or 0 to * indicate the extension is not allowed. If returning 1 then |*found| is set to * 1 if we found a definition for the extension, and |*idx| is set to its index */ static int verify_extension(SSL *s, unsigned int context, unsigned int type, custom_ext_methods *meths, int *found, size_t *idx) { size_t i; size_t builtin_num = OSSL_NELEM(ext_defs); for (i = 0; i < builtin_num; i++) { if (type == ext_defs[i].type) { /* Check we're allowed to use this extension in this context */ if ((context & ext_defs[i].context) == 0) return 0; if (SSL_IS_DTLS(s)) { if ((ext_defs[i].context & EXT_TLS_ONLY) != 0) return 0; } else if ((ext_defs[i].context & EXT_DTLS_ONLY) != 0) { return 0; } *found = 1; *idx = i; return 1; } } if ((context & (EXT_CLIENT_HELLO | EXT_TLS1_2_SERVER_HELLO)) == 0) { /* * Custom extensions only apply to <=TLS1.2. This extension is unknown * in this context - we allow it */ *found = 0; return 1; } /* Check the custom extensions */ if (meths != NULL) { for (i = builtin_num; i < builtin_num + meths->meths_count; i++) { if (meths->meths[i - builtin_num].ext_type == type) { *found = 1; *idx = i; return 1; } } } /* Unknown extension. We allow it */ *found = 0; return 1; } /* * Check whether the context defined for an extension |extctx| means whether * the extension is relevant for the current context |thisctx| or not. Returns * 1 if the extension is relevant for this context, and 0 otherwise */ static int extension_is_relevant(SSL *s, unsigned int extctx, unsigned int thisctx) { if ((SSL_IS_DTLS(s) && (extctx & EXT_TLS_IMPLEMENTATION_ONLY) != 0) || (s->version == SSL3_VERSION && (extctx & EXT_SSL3_ALLOWED) == 0) || (SSL_IS_TLS13(s) && (extctx & EXT_TLS1_2_AND_BELOW_ONLY) != 0) || (!SSL_IS_TLS13(s) && (extctx & EXT_TLS1_3_ONLY) != 0)) return 0; return 1; } /* * Gather a list of all the extensions from the data in |packet]. |context| * tells us which message this extension is for. The raw extension data is * stored in |*res|. In the event of an error the alert type to use is stored in * |*al|. We don't actually process the content of the extensions yet, except to * check their types. This function also runs the initialiser functions for all * known extensions (whether we have collected them or not). * * Per http://tools.ietf.org/html/rfc5246#section-7.4.1.4, there may not be * more than one extension of the same type in a ClientHello or ServerHello. * This function returns 1 if all extensions are unique and we have parsed their * types, and 0 if the extensions contain duplicates, could not be successfully * collected, or an internal error occurred. We only check duplicates for * extensions that we know about. We ignore others. */ int tls_collect_extensions(SSL *s, PACKET *packet, unsigned int context, RAW_EXTENSION **res, int *al) { PACKET extensions = *packet; size_t i = 0, idx; int found = 0; custom_ext_methods *exts = NULL; RAW_EXTENSION *raw_extensions = NULL; /* * Initialise server side custom extensions. Client side is done during * construction of extensions for the ClientHello. */ if ((context & EXT_CLIENT_HELLO) != 0) { exts = &s->cert->srv_ext; custom_ext_init(&s->cert->srv_ext); } else if ((context & EXT_TLS1_2_SERVER_HELLO) != 0) { exts = &s->cert->cli_ext; } raw_extensions = OPENSSL_zalloc((OSSL_NELEM(ext_defs) + (exts != NULL ? exts->meths_count : 0)) * sizeof(RAW_EXTENSION)); if (raw_extensions == NULL) { *al = SSL_AD_INTERNAL_ERROR; SSLerr(SSL_F_TLS_COLLECT_EXTENSIONS, ERR_R_MALLOC_FAILURE); return 0; } while (PACKET_remaining(&extensions) > 0) { unsigned int type; PACKET extension; if (!PACKET_get_net_2(&extensions, &type) || !PACKET_get_length_prefixed_2(&extensions, &extension)) { SSLerr(SSL_F_TLS_COLLECT_EXTENSIONS, SSL_R_BAD_EXTENSION); *al = SSL_AD_DECODE_ERROR; goto err; } /* * Verify this extension is allowed. We only check duplicates for * extensions that we recognise. */ if (!verify_extension(s, context, type, exts, &found, &idx) || (found == 1 && raw_extensions[idx].present == 1)) { SSLerr(SSL_F_TLS_COLLECT_EXTENSIONS, SSL_R_BAD_EXTENSION); *al = SSL_AD_ILLEGAL_PARAMETER; goto err; } if (found) { raw_extensions[idx].data = extension; raw_extensions[idx].present = 1; raw_extensions[idx].type = type; } } /* * Initialise all known extensions relevant to this context, whether we have * found them or not */ for (i = 0; i < OSSL_NELEM(ext_defs); i++) { if(ext_defs[i].init_ext != NULL && (ext_defs[i].context & context) != 0 && extension_is_relevant(s, ext_defs[i].context, context) && !ext_defs[i].init_ext(s, context)) { *al = SSL_AD_INTERNAL_ERROR; goto err; } } *res = raw_extensions; return 1; err: OPENSSL_free(raw_extensions); return 0; } /* * Runs the parser for a given extension with index |idx|. |exts| contains the * list of all parsed extensions previously collected by * tls_collect_extensions(). The parser is only run if it is applicable for the * given |context| and the parser has not already been run. Returns 1 on success * or 0 on failure. In the event of a failure |*al| is populated with a suitable * alert code. If an extension is not present this counted as success. */ int tls_parse_extension(SSL *s, unsigned int idx, int context, RAW_EXTENSION *exts, int *al) { RAW_EXTENSION *currext = &exts[idx]; int (*parser)(SSL *s, PACKET *pkt, int *al) = NULL; /* Skip if the extension is not present */ if (!currext->present) return 1; if (s->tlsext_debug_cb) s->tlsext_debug_cb(s, !s->server, currext->type, PACKET_data(&currext->data), PACKET_remaining(&currext->data), s->tlsext_debug_arg); /* Skip if we've already parsed this extension */ if (currext->parsed) return 1; currext->parsed = 1; if (idx < OSSL_NELEM(ext_defs)) { /* We are handling a built-in extension */ const EXTENSION_DEFINITION *extdef = &ext_defs[idx]; /* Check if extension is defined for our protocol. If not, skip */ if (!extension_is_relevant(s, extdef->context, context)) return 1; parser = s->server ? extdef->parse_client_ext : extdef->parse_server_ext; if (parser != NULL) { if (!parser(s, &currext->data, al)) return 0; return 1; } /* * If the parser is NULL we fall through to the custom extension * processing */ } /* * This is a custom extension. We only allow this if it is a non * resumed session on the server side. * * TODO(TLS1.3): We only allow old style <=TLS1.2 custom extensions. * We're going to need a new mechanism for TLS1.3 to specify which * messages to add the custom extensions to. */ if ((!s->hit || !s->server) && (context & (EXT_CLIENT_HELLO | EXT_TLS1_2_SERVER_HELLO)) != 0 && custom_ext_parse(s, s->server, currext->type, PACKET_data(&currext->data), PACKET_remaining(&currext->data), al) <= 0) return 0; return 1; } /* * Parse all remaining extensions that have not yet been parsed. Also calls the * finalisation for all extensions at the end, whether we collected them or not. * Returns 1 for success or 0 for failure. On failure, |*al| is populated with a * suitable alert code. */ int tls_parse_all_extensions(SSL *s, int context, RAW_EXTENSION *exts, int *al) { size_t loop, numexts = OSSL_NELEM(ext_defs); /* Calculate the number of extensions in the extensions list */ if ((context & EXT_CLIENT_HELLO) != 0) { numexts += s->cert->srv_ext.meths_count; } else if ((context & EXT_TLS1_2_SERVER_HELLO) != 0) { numexts += s->cert->cli_ext.meths_count; } /* Parse each extension in turn */ for (loop = 0; loop < numexts; loop++) { if (!tls_parse_extension(s, loop, context, exts, al)) return 0; } /* * Finalise all known extensions relevant to this context, whether we have * found them or not */ for (loop = 0; loop < OSSL_NELEM(ext_defs); loop++) { if(ext_defs[loop].finalise_ext != NULL && (ext_defs[loop].context & context) != 0 && !ext_defs[loop].finalise_ext(s, context, exts[loop].present, al)) return 0; } return 1; } /* * Construct all the extensions relevant to the current |context| and write * them to |pkt|. Returns 1 on success or 0 on failure. If a failure occurs then * |al| is populated with a suitable alert code. */ int tls_construct_extensions(SSL *s, WPACKET *pkt, unsigned int context, int *al) { size_t loop; int addcustom = 0; int min_version, max_version = 0, reason, tmpal; /* * Normally if something goes wrong during construction it's an internal * error. We can always override this later. */ tmpal = SSL_AD_INTERNAL_ERROR; if (!WPACKET_start_sub_packet_u16(pkt) /* * If extensions are of zero length then we don't even add the * extensions length bytes to a ClientHello/ServerHello in SSLv3 */ || ((context & (EXT_CLIENT_HELLO | EXT_TLS1_2_SERVER_HELLO)) != 0 && s->version == SSL3_VERSION && !WPACKET_set_flags(pkt, WPACKET_FLAGS_ABANDON_ON_ZERO_LENGTH))) { SSLerr(SSL_F_TLS_CONSTRUCT_EXTENSIONS, ERR_R_INTERNAL_ERROR); goto err; } if ((context & EXT_CLIENT_HELLO) != 0) { reason = ssl_get_client_min_max_version(s, &min_version, &max_version); if (reason != 0) { SSLerr(SSL_F_TLS_CONSTRUCT_EXTENSIONS, reason); goto err; } } /* Add custom extensions first */ if ((context & EXT_CLIENT_HELLO) != 0) { custom_ext_init(&s->cert->cli_ext); addcustom = 1; } else if ((context & EXT_TLS1_2_SERVER_HELLO) != 0) { /* * We already initialised the custom extensions during ClientHello * parsing. * * TODO(TLS1.3): We're going to need a new custom extension mechanism * for TLS1.3, so that custom extensions can specify which of the * multiple message they wish to add themselves to. */ addcustom = 1; } if (addcustom && !custom_ext_add(s, s->server, pkt, &tmpal)) { SSLerr(SSL_F_TLS_CONSTRUCT_EXTENSIONS, ERR_R_INTERNAL_ERROR); goto err; } for (loop = 0; loop < OSSL_NELEM(ext_defs); loop++) { int (*construct)(SSL *s, WPACKET *pkt, int *al); /* Skip if not relevant for our context */ if ((ext_defs[loop].context & context) == 0) continue; construct = s->server ? ext_defs[loop].construct_server_ext : ext_defs[loop].construct_client_ext; /* Check if this extension is defined for our protocol. If not, skip */ if ((SSL_IS_DTLS(s) && (ext_defs[loop].context & EXT_TLS_IMPLEMENTATION_ONLY) != 0) || (s->version == SSL3_VERSION && (ext_defs[loop].context & EXT_SSL3_ALLOWED) == 0) || (SSL_IS_TLS13(s) && (ext_defs[loop].context & EXT_TLS1_2_AND_BELOW_ONLY) != 0) || (!SSL_IS_TLS13(s) && (ext_defs[loop].context & EXT_TLS1_3_ONLY) != 0 && (context & EXT_CLIENT_HELLO) == 0) || ((ext_defs[loop].context & EXT_TLS1_3_ONLY) != 0 && (context & EXT_CLIENT_HELLO) != 0 && (SSL_IS_DTLS(s) || max_version < TLS1_3_VERSION)) || construct == NULL) continue; if (!construct(s, pkt, &tmpal)) goto err; } if (!WPACKET_close(pkt)) { SSLerr(SSL_F_TLS_CONSTRUCT_EXTENSIONS, ERR_R_INTERNAL_ERROR); goto err; } return 1; err: *al = tmpal; return 0; } /* * Built in extension finalisation and initialisation functions. All initialise * or finalise the associated extension type for the given |context|. For * finalisers |sent| is set to 1 if we saw the extension during parsing, and 0 * otherwise. These functions return 1 on success or 0 on failure. In the event * of a failure then |*al| is populated with a suitable error code. */ static int tls_ext_final_renegotiate(SSL *s, unsigned int context, int sent, int *al) { if (!s->server) { /* * Check if we can connect to a server that doesn't support safe * renegotiation */ if (!(s->options & SSL_OP_LEGACY_SERVER_CONNECT) && !(s->options & SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION) && !sent) { *al = SSL_AD_HANDSHAKE_FAILURE; SSLerr(SSL_F_TLS_EXT_FINAL_RENEGOTIATE, SSL_R_UNSAFE_LEGACY_RENEGOTIATION_DISABLED); return 0; } return 1; } /* Need RI if renegotiating */ if (s->renegotiate && !(s->options & SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION) && !sent) { *al = SSL_AD_HANDSHAKE_FAILURE; SSLerr(SSL_F_TLS_EXT_FINAL_RENEGOTIATE, SSL_R_UNSAFE_LEGACY_RENEGOTIATION_DISABLED); return 0; } return 1; } static int tls_ext_init_server_name(SSL *s, unsigned int context) { if (s->server) s->servername_done = 0; return 1; } static int tls_ext_final_server_name(SSL *s, unsigned int context, int sent, int *al) { int ret = SSL_TLSEXT_ERR_NOACK; int altmp = SSL_AD_UNRECOGNIZED_NAME; if (s->ctx != NULL && s->ctx->tlsext_servername_callback != 0) ret = s->ctx->tlsext_servername_callback(s, &altmp, s->ctx->tlsext_servername_arg); else if (s->initial_ctx != NULL && s->initial_ctx->tlsext_servername_callback != 0) ret = s->initial_ctx->tlsext_servername_callback(s, &altmp, s->initial_ctx->tlsext_servername_arg); switch (ret) { case SSL_TLSEXT_ERR_ALERT_FATAL: *al = altmp; return 0; case SSL_TLSEXT_ERR_ALERT_WARNING: *al = altmp; return 1; case SSL_TLSEXT_ERR_NOACK: s->servername_done = 0; return 1; default: return 1; } } #ifndef OPENSSL_NO_EC static int tls_ext_final_ec_pt_formats(SSL *s, unsigned int context, int sent, int *al) { unsigned long alg_k, alg_a; if (s->server) return 1; alg_k = s->s3->tmp.new_cipher->algorithm_mkey; alg_a = s->s3->tmp.new_cipher->algorithm_auth; /* * If we are client and using an elliptic curve cryptography cipher * suite, then if server returns an EC point formats lists extension it * must contain uncompressed. */ if ((s->tlsext_ecpointformatlist != NULL) && (s->tlsext_ecpointformatlist_length > 0) && (s->session->tlsext_ecpointformatlist != NULL) && (s->session->tlsext_ecpointformatlist_length > 0) && ((alg_k & SSL_kECDHE) || (alg_a & SSL_aECDSA))) { /* we are using an ECC cipher */ size_t i; unsigned char *list; int found_uncompressed = 0; list = s->session->tlsext_ecpointformatlist; for (i = 0; i < s->session->tlsext_ecpointformatlist_length; i++) { if (*(list++) == TLSEXT_ECPOINTFORMAT_uncompressed) { found_uncompressed = 1; break; } } if (!found_uncompressed) { SSLerr(SSL_F_TLS_EXT_FINAL_EC_PT_FORMATS, SSL_R_TLS_INVALID_ECPOINTFORMAT_LIST); return 0; } } return 1; } #endif static int tls_ext_init_session_ticket(SSL *s, unsigned int context) { if (!s->server) s->tlsext_ticket_expected = 0; return 1; } static int tls_ext_init_status_request(SSL *s, unsigned int context) { if (s->server) s->tlsext_status_type = -1; return 1; } static int tls_ext_final_status_request(SSL *s, unsigned int context, int sent, int *al) { if (s->server) return 1; /* * Ensure we get sensible values passed to tlsext_status_cb in the event * that we don't receive a status message */ OPENSSL_free(s->tlsext_ocsp_resp); s->tlsext_ocsp_resp = NULL; s->tlsext_ocsp_resplen = 0; return 1; } #ifndef OPENSSL_NO_NEXTPROTONEG static int tls_ext_init_npn(SSL *s, unsigned int context) { s->s3->next_proto_neg_seen = 0; return 1; } #endif static int tls_ext_init_alpn(SSL *s, unsigned int context) { OPENSSL_free(s->s3->alpn_selected); s->s3->alpn_selected = NULL; if (s->server) { s->s3->alpn_selected_len = 0; OPENSSL_free(s->s3->alpn_proposed); s->s3->alpn_proposed = NULL; s->s3->alpn_proposed_len = 0; } return 1; } static int tls_ext_final_alpn(SSL *s, unsigned int context, int sent, int *al) { const unsigned char *selected = NULL; unsigned char selected_len = 0; if (!s->server) return 1; if (s->ctx->alpn_select_cb != NULL && s->s3->alpn_proposed != NULL) { int r = s->ctx->alpn_select_cb(s, &selected, &selected_len, s->s3->alpn_proposed, (unsigned int)s->s3->alpn_proposed_len, s->ctx->alpn_select_cb_arg); if (r == SSL_TLSEXT_ERR_OK) { OPENSSL_free(s->s3->alpn_selected); s->s3->alpn_selected = OPENSSL_memdup(selected, selected_len); if (s->s3->alpn_selected == NULL) { *al = SSL_AD_INTERNAL_ERROR; return 0; } s->s3->alpn_selected_len = selected_len; #ifndef OPENSSL_NO_NEXTPROTONEG /* ALPN takes precedence over NPN. */ s->s3->next_proto_neg_seen = 0; #endif } else { *al = SSL_AD_NO_APPLICATION_PROTOCOL; return 0; } } return 1; } static int tls_ext_init_sig_algs(SSL *s, unsigned int context) { /* Clear any signature algorithms extension received */ OPENSSL_free(s->s3->tmp.peer_sigalgs); s->s3->tmp.peer_sigalgs = NULL; return 1; } #ifndef OPENSSL_NO_SRP static int tls_ext_init_srp(SSL *s, unsigned int context) { OPENSSL_free(s->srp_ctx.login); s->srp_ctx.login = NULL; return 1; } #endif static int tls_ext_init_etm(SSL *s, unsigned int context) { s->s3->flags &= ~TLS1_FLAGS_ENCRYPT_THEN_MAC; return 1; } static int tls_ext_init_ems(SSL *s, unsigned int context) { if (!s->server) s->s3->flags &= ~TLS1_FLAGS_RECEIVED_EXTMS; return 1; } static int tls_ext_final_ems(SSL *s, unsigned int context, int sent, int *al) { if (!s->server && s->hit) { /* * Check extended master secret extension is consistent with * original session. */ if (!(s->s3->flags & TLS1_FLAGS_RECEIVED_EXTMS) != !(s->session->flags & SSL_SESS_FLAG_EXTMS)) { *al = SSL_AD_HANDSHAKE_FAILURE; SSLerr(SSL_F_TLS_EXT_FINAL_EMS, SSL_R_INCONSISTENT_EXTMS); return 0; } } return 1; } #ifndef OPENSSL_NO_SRTP static int tls_ext_init_srtp(SSL *s, unsigned int context) { if (s->server) s->srtp_profile = NULL; return 1; } #endif