X-Git-Url: https://git.openssl.org/?p=openssl.git;a=blobdiff_plain;f=ssl%2Fstatem%2Fextensions.c;h=b4d85d958c5f1cb430a970c14631e01dc8d4c8a6;hp=c98a2055c2d0f69a28844dbc4bb2a24aced02891;hb=bd91e3c870402c4b10909c47082daece473d22ef;hpb=4b299b8e174cd58f762f0f184ceac7955e4227c4 diff --git a/ssl/statem/extensions.c b/ssl/statem/extensions.c index c98a2055c2..b4d85d958c 100644 --- a/ssl/statem/extensions.c +++ b/ssl/statem/extensions.c @@ -1,5 +1,5 @@ /* - * Copyright 2016 The OpenSSL Project Authors. All Rights Reserved. + * Copyright 2016-2017 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 @@ -7,367 +7,539 @@ * https://www.openssl.org/source/license.html */ -#include -#include +#include #include "../ssl_locl.h" #include "statem_locl.h" -static int tls_parse_clienthello_renegotiate(SSL *s, PACKET *pkt, int *al); -static int tls_parse_clienthello_server_name(SSL *s, PACKET *pkt, int *al); -#ifndef OPENSSL_NO_SRP -static int tls_parse_clienthello_srp(SSL *s, PACKET *pkt, int *al); -#endif +static int final_renegotiate(SSL *s, unsigned int context, int sent, + int *al); +static int init_server_name(SSL *s, unsigned int context); +static int final_server_name(SSL *s, unsigned int context, int sent, + int *al); #ifndef OPENSSL_NO_EC -static int tls_parse_clienthello_ec_pt_formats(SSL *s, PACKET *pkt, int *al); -static int tls_parse_clienthello_supported_groups(SSL *s, PACKET *pkt, int *al); +static int final_ec_pt_formats(SSL *s, unsigned int context, int sent, + int *al); +#endif +static int init_session_ticket(SSL *s, unsigned int context); +#ifndef OPENSSL_NO_OCSP +static int init_status_request(SSL *s, unsigned int context); #endif -static int tls_parse_clienthello_session_ticket(SSL *s, PACKET *pkt, int *al); -static int tls_parse_clienthello_sig_algs(SSL *s, PACKET *pkt, int *al); -static int tls_parse_clienthello_status_request(SSL *s, PACKET *pkt, int *al); #ifndef OPENSSL_NO_NEXTPROTONEG -static int tls_parse_clienthello_npn(SSL *s, PACKET *pkt, int *al); +static int init_npn(SSL *s, unsigned int context); +#endif +static int init_alpn(SSL *s, unsigned int context); +static int final_alpn(SSL *s, unsigned int context, int sent, int *al); +static int init_sig_algs(SSL *s, unsigned int context); +static int init_certificate_authorities(SSL *s, unsigned int context); +static EXT_RETURN tls_construct_certificate_authorities(SSL *s, WPACKET *pkt, + unsigned int context, + X509 *x, + size_t chainidx, + int *al); +static int tls_parse_certificate_authorities(SSL *s, PACKET *pkt, + unsigned int context, X509 *x, + size_t chainidx, int *al); +#ifndef OPENSSL_NO_SRP +static int init_srp(SSL *s, unsigned int context); +#endif +static int init_etm(SSL *s, unsigned int context); +static int init_ems(SSL *s, unsigned int context); +static int final_ems(SSL *s, unsigned int context, int sent, int *al); +static int init_psk_kex_modes(SSL *s, unsigned int context); +#ifndef OPENSSL_NO_EC +static int final_key_share(SSL *s, unsigned int context, int sent, int *al); #endif -static int tls_parse_clienthello_alpn(SSL *s, PACKET *pkt, int *al); #ifndef OPENSSL_NO_SRTP -static int tls_parse_clienthello_use_srtp(SSL *s, PACKET *pkt, int *al); +static int init_srtp(SSL *s, unsigned int context); #endif -static int tls_parse_clienthello_etm(SSL *s, PACKET *pkt, int *al); -static int tls_parse_clienthello_key_share(SSL *s, PACKET *pkt, int *al); -static int tls_parse_clienthello_ems(SSL *s, PACKET *pkt, int *al); +static int final_sig_algs(SSL *s, unsigned int context, int sent, int *al); +static int final_early_data(SSL *s, unsigned int context, int sent, int *al); -typedef struct { - /* The ID for the extension */ +/* Structure to define a built-in extension */ +typedef struct extensions_definition_st { + /* The defined type for the extension */ unsigned int type; - int (*server_parse)(SSL *s, PACKET *pkt, int *al); - int (*client_parse)(SSL *s, PACKET *pkt, int *al); - int (*server_construct)(SSL *s, WPACKET *pkt, int *al); - int (*client_construct)(SSL *s, WPACKET *pkt, int *al); + /* + * The context that this extension applies to, e.g. what messages and + * protocol versions + */ unsigned int context; + /* + * Initialise extension before parsing. Always called for relevant contexts + * even if extension not present + */ + int (*init)(SSL *s, unsigned int context); + /* Parse extension sent from client to server */ + int (*parse_ctos)(SSL *s, PACKET *pkt, unsigned int context, X509 *x, + size_t chainidx, int *al); + /* Parse extension send from server to client */ + int (*parse_stoc)(SSL *s, PACKET *pkt, unsigned int context, X509 *x, + size_t chainidx, int *al); + /* Construct extension sent from server to client */ + EXT_RETURN (*construct_stoc)(SSL *s, WPACKET *pkt, unsigned int context, + X509 *x, size_t chainidx, int *al); + /* Construct extension sent from client to server */ + EXT_RETURN (*construct_ctos)(SSL *s, WPACKET *pkt, unsigned int context, + X509 *x, size_t chainidx, 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 (*final)(SSL *s, unsigned int context, int sent, int *al); } EXTENSION_DEFINITION; /* - * TODO(TLS1.3): Temporarily modified the definitions below to put all TLS1.3 - * extensions in the ServerHello for now. That needs to be put back to correct - * setting once encrypted extensions is working properly. + * 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 ( TLSEXT_IDX_* ) defined in ssl_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 particular protocol or protocol version. + * + * TODO(TLS1.3): Make sure we have a test to check the consistency of these */ +#define INVALID_EXTENSION { 0x10000, 0, NULL, NULL, NULL, NULL, NULL, NULL } static const EXTENSION_DEFINITION ext_defs[] = { { TLSEXT_TYPE_renegotiate, - tls_parse_clienthello_renegotiate, - NULL, - NULL, - NULL, - EXT_CLIENT_HELLO | EXT_TLS1_2_SERVER_HELLO | EXT_SSL3_ALLOWED - | EXT_TLS1_2_AND_BELOW_ONLY + SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_2_SERVER_HELLO + | SSL_EXT_SSL3_ALLOWED | SSL_EXT_TLS1_2_AND_BELOW_ONLY, + NULL, tls_parse_ctos_renegotiate, tls_parse_stoc_renegotiate, + tls_construct_stoc_renegotiate, tls_construct_ctos_renegotiate, + final_renegotiate }, { TLSEXT_TYPE_server_name, - tls_parse_clienthello_server_name, - NULL, - NULL, - NULL, - EXT_CLIENT_HELLO | EXT_TLS1_2_SERVER_HELLO - | /*EXT_TLS1_3_ENCRYPTED_EXTENSIONS*/EXT_TLS1_3_SERVER_HELLO + SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_2_SERVER_HELLO + | SSL_EXT_TLS1_3_ENCRYPTED_EXTENSIONS, + init_server_name, + tls_parse_ctos_server_name, tls_parse_stoc_server_name, + tls_construct_stoc_server_name, tls_construct_ctos_server_name, + final_server_name }, #ifndef OPENSSL_NO_SRP { TLSEXT_TYPE_srp, - tls_parse_clienthello_srp, - NULL, - NULL, - NULL, - EXT_CLIENT_HELLO | EXT_TLS1_2_SERVER_HELLO | EXT_TLS1_2_AND_BELOW_ONLY + SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_2_AND_BELOW_ONLY, + init_srp, tls_parse_ctos_srp, NULL, NULL, tls_construct_ctos_srp, NULL }, +#else + INVALID_EXTENSION, #endif #ifndef OPENSSL_NO_EC { TLSEXT_TYPE_ec_point_formats, - tls_parse_clienthello_ec_pt_formats, - NULL, - NULL, - NULL, - EXT_CLIENT_HELLO | EXT_TLS1_2_AND_BELOW_ONLY + SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_2_SERVER_HELLO + | SSL_EXT_TLS1_2_AND_BELOW_ONLY, + NULL, tls_parse_ctos_ec_pt_formats, tls_parse_stoc_ec_pt_formats, + tls_construct_stoc_ec_pt_formats, tls_construct_ctos_ec_pt_formats, + final_ec_pt_formats }, { TLSEXT_TYPE_supported_groups, - tls_parse_clienthello_supported_groups, - NULL, - NULL, - NULL, - EXT_CLIENT_HELLO - | /*EXT_TLS1_3_ENCRYPTED_EXTENSIONS*/EXT_TLS1_3_SERVER_HELLO + SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_3_ENCRYPTED_EXTENSIONS, + NULL, tls_parse_ctos_supported_groups, NULL, + tls_construct_stoc_supported_groups, + tls_construct_ctos_supported_groups, NULL }, +#else + INVALID_EXTENSION, + INVALID_EXTENSION, #endif { TLSEXT_TYPE_session_ticket, - tls_parse_clienthello_session_ticket, - NULL, - NULL, - NULL, - EXT_CLIENT_HELLO | EXT_TLS1_2_SERVER_HELLO | EXT_TLS1_2_AND_BELOW_ONLY + SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_2_SERVER_HELLO + | SSL_EXT_TLS1_2_AND_BELOW_ONLY, + init_session_ticket, tls_parse_ctos_session_ticket, + tls_parse_stoc_session_ticket, tls_construct_stoc_session_ticket, + tls_construct_ctos_session_ticket, NULL }, { TLSEXT_TYPE_signature_algorithms, - tls_parse_clienthello_sig_algs, - NULL, - NULL, - NULL, - EXT_CLIENT_HELLO + SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_3_CERTIFICATE_REQUEST, + init_sig_algs, tls_parse_ctos_sig_algs, + tls_parse_ctos_sig_algs, tls_construct_ctos_sig_algs, + tls_construct_ctos_sig_algs, final_sig_algs }, +#ifndef OPENSSL_NO_OCSP { TLSEXT_TYPE_status_request, - tls_parse_clienthello_status_request, - NULL, - NULL, - NULL, - EXT_CLIENT_HELLO | EXT_TLS1_2_SERVER_HELLO - | /*EXT_TLS1_3_CERTIFICATE*/EXT_TLS1_3_SERVER_HELLO + SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_2_SERVER_HELLO + | SSL_EXT_TLS1_3_CERTIFICATE, + init_status_request, tls_parse_ctos_status_request, + tls_parse_stoc_status_request, tls_construct_stoc_status_request, + tls_construct_ctos_status_request, NULL }, +#else + INVALID_EXTENSION, +#endif #ifndef OPENSSL_NO_NEXTPROTONEG { TLSEXT_TYPE_next_proto_neg, - tls_parse_clienthello_npn, - NULL, - NULL, - NULL, - EXT_CLIENT_HELLO | EXT_TLS1_2_SERVER_HELLO | EXT_TLS1_2_AND_BELOW_ONLY + SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_2_SERVER_HELLO + | SSL_EXT_TLS1_2_AND_BELOW_ONLY, + init_npn, tls_parse_ctos_npn, tls_parse_stoc_npn, + tls_construct_stoc_next_proto_neg, tls_construct_ctos_npn, NULL }, +#else + INVALID_EXTENSION, #endif { + /* + * Must appear in this list after server_name so that finalisation + * happens after server_name callbacks + */ TLSEXT_TYPE_application_layer_protocol_negotiation, - tls_parse_clienthello_alpn, - NULL, - NULL, - NULL, - EXT_CLIENT_HELLO | EXT_TLS1_2_SERVER_HELLO - | /*EXT_TLS1_3_ENCRYPTED_EXTENSIONS*/EXT_TLS1_3_SERVER_HELLO + SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_2_SERVER_HELLO + | SSL_EXT_TLS1_3_ENCRYPTED_EXTENSIONS, + init_alpn, tls_parse_ctos_alpn, tls_parse_stoc_alpn, + tls_construct_stoc_alpn, tls_construct_ctos_alpn, final_alpn }, +#ifndef OPENSSL_NO_SRTP { TLSEXT_TYPE_use_srtp, - tls_parse_clienthello_use_srtp, - NULL, - NULL, - NULL, - EXT_CLIENT_HELLO | EXT_TLS1_2_SERVER_HELLO - | EXT_TLS1_3_ENCRYPTED_EXTENSIONS | EXT_DTLS_ONLY + SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_2_SERVER_HELLO + | SSL_EXT_TLS1_3_ENCRYPTED_EXTENSIONS | SSL_EXT_DTLS_ONLY, + init_srtp, tls_parse_ctos_use_srtp, tls_parse_stoc_use_srtp, + tls_construct_stoc_use_srtp, tls_construct_ctos_use_srtp, NULL }, +#else + INVALID_EXTENSION, +#endif { TLSEXT_TYPE_encrypt_then_mac, - tls_parse_clienthello_etm, - NULL, - NULL, - NULL, - EXT_CLIENT_HELLO | EXT_TLS1_2_SERVER_HELLO | EXT_TLS1_2_AND_BELOW_ONLY + SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_2_SERVER_HELLO + | SSL_EXT_TLS1_2_AND_BELOW_ONLY, + init_etm, tls_parse_ctos_etm, tls_parse_stoc_etm, + tls_construct_stoc_etm, tls_construct_ctos_etm, NULL }, +#ifndef OPENSSL_NO_CT { TLSEXT_TYPE_signed_certificate_timestamp, + SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_2_SERVER_HELLO + | SSL_EXT_TLS1_3_CERTIFICATE, + 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, - NULL, - NULL, - NULL, - EXT_CLIENT_HELLO | EXT_TLS1_2_SERVER_HELLO - | /*EXT_TLS1_3_CERTIFICATE*/EXT_TLS1_3_SERVER_HELLO + NULL, tls_parse_stoc_sct, NULL, tls_construct_ctos_sct, NULL }, +#else + INVALID_EXTENSION, +#endif { TLSEXT_TYPE_extended_master_secret, - tls_parse_clienthello_ems, - NULL, - NULL, - NULL, - EXT_CLIENT_HELLO | EXT_TLS1_2_SERVER_HELLO | EXT_TLS1_2_AND_BELOW_ONLY + SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_2_SERVER_HELLO + | SSL_EXT_TLS1_2_AND_BELOW_ONLY, + init_ems, tls_parse_ctos_ems, tls_parse_stoc_ems, + tls_construct_stoc_ems, tls_construct_ctos_ems, final_ems }, { TLSEXT_TYPE_supported_versions, - /* Processed inline as part of version selection */ - NULL, - NULL, - NULL, + SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS_IMPLEMENTATION_ONLY + | SSL_EXT_TLS1_3_ONLY, NULL, - EXT_CLIENT_HELLO | EXT_TLS_IMPLEMENTATION_ONLY + /* Processed inline as part of version selection */ + NULL, NULL, NULL, tls_construct_ctos_supported_versions, NULL }, { - TLSEXT_TYPE_padding, - /* We send this, but don't read it */ - NULL, - NULL, - NULL, - NULL, - EXT_CLIENT_HELLO + TLSEXT_TYPE_psk_kex_modes, + SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS_IMPLEMENTATION_ONLY + | SSL_EXT_TLS1_3_ONLY, + init_psk_kex_modes, tls_parse_ctos_psk_kex_modes, NULL, NULL, + tls_construct_ctos_psk_kex_modes, NULL }, +#ifndef OPENSSL_NO_EC { + /* + * Must be in this list after supported_groups. We need that to have + * been parsed before we do this one. + */ TLSEXT_TYPE_key_share, - tls_parse_clienthello_key_share, - NULL, - NULL, + SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_3_SERVER_HELLO + | SSL_EXT_TLS1_3_HELLO_RETRY_REQUEST | SSL_EXT_TLS_IMPLEMENTATION_ONLY + | SSL_EXT_TLS1_3_ONLY, + NULL, tls_parse_ctos_key_share, tls_parse_stoc_key_share, + tls_construct_stoc_key_share, tls_construct_ctos_key_share, + final_key_share + }, +#endif + { + TLSEXT_TYPE_cookie, + SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_3_HELLO_RETRY_REQUEST + | SSL_EXT_TLS_IMPLEMENTATION_ONLY | SSL_EXT_TLS1_3_ONLY, + NULL, NULL, tls_parse_stoc_cookie, NULL, tls_construct_ctos_cookie, + NULL + }, + { + /* + * Special unsolicited ServerHello extension only used when + * SSL_OP_CRYPTOPRO_TLSEXT_BUG is set + */ + TLSEXT_TYPE_cryptopro_bug, + SSL_EXT_TLS1_2_SERVER_HELLO | SSL_EXT_TLS1_2_AND_BELOW_ONLY, + NULL, NULL, NULL, tls_construct_stoc_cryptopro_bug, NULL, NULL + }, + { + TLSEXT_TYPE_early_data, + SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_3_ENCRYPTED_EXTENSIONS + | SSL_EXT_TLS1_3_NEW_SESSION_TICKET, + NULL, tls_parse_ctos_early_data, tls_parse_stoc_early_data, + tls_construct_stoc_early_data, tls_construct_ctos_early_data, + final_early_data + }, + { + TLSEXT_TYPE_certificate_authorities, + SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_3_CERTIFICATE_REQUEST + | SSL_EXT_TLS1_3_ONLY, + init_certificate_authorities, + tls_parse_certificate_authorities, tls_parse_certificate_authorities, + tls_construct_certificate_authorities, + tls_construct_certificate_authorities, NULL, + }, + { + /* Must be immediately before pre_shared_key */ + TLSEXT_TYPE_padding, + SSL_EXT_CLIENT_HELLO, NULL, - EXT_CLIENT_HELLO | EXT_TLS1_3_SERVER_HELLO - | EXT_TLS1_3_HELLO_RETRY_REQUEST | EXT_TLS_IMPLEMENTATION_ONLY - | EXT_TLS1_3_ONLY + /* We send this, but don't read it */ + NULL, NULL, NULL, tls_construct_ctos_padding, NULL + }, + { + /* Required by the TLSv1.3 spec to always be the last extension */ + TLSEXT_TYPE_psk, + SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_3_SERVER_HELLO + | SSL_EXT_TLS_IMPLEMENTATION_ONLY | SSL_EXT_TLS1_3_ONLY, + NULL, tls_parse_ctos_psk, tls_parse_stoc_psk, tls_construct_stoc_psk, + tls_construct_ctos_psk, NULL } }; -/* - * Comparison function used in a call to qsort (see tls_collect_extensions() - * below.) - * The two arguments |p1| and |p2| are expected to be pointers to RAW_EXTENSIONs - * - * Returns: - * 1 if the type for p1 is greater than p2 - * 0 if the type for p1 and p2 are the same - * -1 if the type for p1 is less than p2 - */ -static int compare_extensions(const void *p1, const void *p2) +/* Check whether an extension's context matches the current context */ +static int validate_context(SSL *s, unsigned int extctx, unsigned int thisctx) { - const RAW_EXTENSION *e1 = (const RAW_EXTENSION *)p1; - const RAW_EXTENSION *e2 = (const RAW_EXTENSION *)p2; + /* Check we're allowed to use this extension in this context */ + if ((thisctx & extctx) == 0) + return 0; - if (e1->type < e2->type) - return -1; - else if (e1->type > e2->type) - return 1; + if (SSL_IS_DTLS(s)) { + if ((extctx & SSL_EXT_TLS_ONLY) != 0) + return 0; + } else if ((extctx & SSL_EXT_DTLS_ONLY) != 0) { + return 0; + } - return 0; + return 1; } /* * 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. + * indicate the extension is not allowed. If returning 1 then |*found| is set to + * the definition for the extension we found. */ -static int verify_extension(SSL *s, unsigned int context, unsigned int type) +static int verify_extension(SSL *s, unsigned int context, unsigned int type, + custom_ext_methods *meths, RAW_EXTENSION *rawexlist, + RAW_EXTENSION **found) { size_t i; + size_t builtin_num = OSSL_NELEM(ext_defs); + const EXTENSION_DEFINITION *thisext; - for (i = 0; i < OSSL_NELEM(ext_defs); 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) + for (i = 0, thisext = ext_defs; i < builtin_num; i++, thisext++) { + if (type == thisext->type) { + if (!validate_context(s, thisext->context, context)) 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 = &rawexlist[i]; + return 1; + } + } + + /* Check the custom extensions */ + if (meths != NULL) { + size_t offset = 0; + ENDPOINT role = ENDPOINT_BOTH; + custom_ext_method *meth = NULL; + if ((context & SSL_EXT_CLIENT_HELLO) != 0) + role = ENDPOINT_SERVER; + else if ((context & SSL_EXT_TLS1_2_SERVER_HELLO) != 0) + role = ENDPOINT_CLIENT; + + meth = custom_ext_find(meths, role, type, &offset); + if (meth != NULL) { + if (!validate_context(s, meth->context, context)) + return 0; + *found = &rawexlist[offset + builtin_num]; return 1; } } /* Unknown extension. We allow it */ + *found = NULL; return 1; } /* - * Finds an extension definition for the give extension |type|. - * Returns 1 if found and stores the definition in |*def|, or returns 0 - * otherwise. + * 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 find_extension_definition(SSL *s, unsigned int type, - const EXTENSION_DEFINITION **def) +int extension_is_relevant(SSL *s, unsigned int extctx, unsigned int thisctx) { - size_t i; - - for (i = 0; i < OSSL_NELEM(ext_defs); i++) { - if (type == ext_defs[i].type) { - *def = &ext_defs[i]; - return 1; - } - } + if ((SSL_IS_DTLS(s) + && (extctx & SSL_EXT_TLS_IMPLEMENTATION_ONLY) != 0) + || (s->version == SSL3_VERSION + && (extctx & SSL_EXT_SSL3_ALLOWED) == 0) + || (SSL_IS_TLS13(s) + && (extctx & SSL_EXT_TLS1_2_AND_BELOW_ONLY) != 0) + || (!SSL_IS_TLS13(s) && (extctx & SSL_EXT_TLS1_3_ONLY) != 0) + || (s->hit && (extctx & SSL_EXT_IGNORE_ON_RESUMPTION) != 0)) + return 0; - /* Unknown extension */ - 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| with the number of found extensions in |*numfound|. In the - * event of an error the alert type to use is stored in |*ad|. We don't actually - * process the content of the extensions yet, except to check their types. + * stored in |*res| on success. 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 if |init| is nonzero (whether we have + * collected them or not). If successful the caller is responsible for freeing + * the contents of |*res|. * * 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 - * parsed, or an internal error occurred. - */ -/* - * TODO(TLS1.3): Refactor ServerHello extension parsing to use this and then - * remove tls1_check_duplicate_extensions() + * found, 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, size_t *numfound, int *ad) + RAW_EXTENSION **res, int *al, size_t *len, + int init) { PACKET extensions = *packet; - size_t num_extensions = 0, i = 0; + size_t i = 0; + size_t num_exts; + custom_ext_methods *exts = &s->cert->custext; RAW_EXTENSION *raw_extensions = NULL; + const EXTENSION_DEFINITION *thisexd; + + *res = NULL; + + /* + * Initialise server side custom extensions. Client side is done during + * construction of extensions for the ClientHello. + */ + if ((context & SSL_EXT_CLIENT_HELLO) != 0) + custom_ext_init(&s->cert->custext); + + num_exts = OSSL_NELEM(ext_defs) + (exts != NULL ? exts->meths_count : 0); + raw_extensions = OPENSSL_zalloc(num_exts * sizeof(*raw_extensions)); + if (raw_extensions == NULL) { + *al = SSL_AD_INTERNAL_ERROR; + SSLerr(SSL_F_TLS_COLLECT_EXTENSIONS, ERR_R_MALLOC_FAILURE); + return 0; + } - /* First pass: count the extensions. */ while (PACKET_remaining(&extensions) > 0) { - unsigned int type; + unsigned int type, idx; PACKET extension; + RAW_EXTENSION *thisex; if (!PACKET_get_net_2(&extensions, &type) || !PACKET_get_length_prefixed_2(&extensions, &extension)) { SSLerr(SSL_F_TLS_COLLECT_EXTENSIONS, SSL_R_BAD_EXTENSION); - *ad = SSL_AD_DECODE_ERROR; + *al = SSL_AD_DECODE_ERROR; goto err; } - /* Verify this extension is allowed */ - if (!verify_extension(s, context, type)) { + /* + * Verify this extension is allowed. We only check duplicates for + * extensions that we recognise. We also have a special case for the + * PSK extension, which must be the last one in the ClientHello. + */ + if (!verify_extension(s, context, type, exts, raw_extensions, &thisex) + || (thisex != NULL && thisex->present == 1) + || (type == TLSEXT_TYPE_psk + && (context & SSL_EXT_CLIENT_HELLO) != 0 + && PACKET_remaining(&extensions) != 0)) { SSLerr(SSL_F_TLS_COLLECT_EXTENSIONS, SSL_R_BAD_EXTENSION); - *ad = SSL_AD_ILLEGAL_PARAMETER; + *al = SSL_AD_ILLEGAL_PARAMETER; goto err; } - num_extensions++; - } - - if (num_extensions > 0) { - raw_extensions = OPENSSL_zalloc(sizeof(*raw_extensions) - * num_extensions); - if (raw_extensions == NULL) { - *ad = SSL_AD_INTERNAL_ERROR; - SSLerr(SSL_F_TLS_COLLECT_EXTENSIONS, ERR_R_MALLOC_FAILURE); + idx = thisex - raw_extensions; + /*- + * Check that we requested this extension (if appropriate). Requests can + * be sent in the ClientHello and CertificateRequest. Unsolicited + * extensions can be sent in the NewSessionTicket. We only do this for + * the built-in extensions. Custom extensions have a different but + * similar check elsewhere. + * Special cases: + * - The HRR cookie extension is unsolicited + * - The renegotiate extension is unsolicited (the client signals + * support via an SCSV) + * - The signed_certificate_timestamp extension can be provided by a + * custom extension or by the built-in version. We let the extension + * itself handle unsolicited response checks. + */ + if (idx < OSSL_NELEM(ext_defs) + && (context & (SSL_EXT_CLIENT_HELLO + | SSL_EXT_TLS1_3_CERTIFICATE_REQUEST + | SSL_EXT_TLS1_3_NEW_SESSION_TICKET)) == 0 + && type != TLSEXT_TYPE_cookie + && type != TLSEXT_TYPE_renegotiate + && type != TLSEXT_TYPE_signed_certificate_timestamp + && (s->ext.extflags[idx] & SSL_EXT_FLAG_SENT) == 0) { + SSLerr(SSL_F_TLS_COLLECT_EXTENSIONS, SSL_R_UNSOLICITED_EXTENSION); + *al = SSL_AD_UNSUPPORTED_EXTENSION; goto err; } - - /* Second pass: collect the extensions. */ - for (i = 0; i < num_extensions; i++) { - if (!PACKET_get_net_2(packet, &raw_extensions[i].type) || - !PACKET_get_length_prefixed_2(packet, - &raw_extensions[i].data)) { - /* This should not happen. */ - *ad = SSL_AD_INTERNAL_ERROR; - SSLerr(SSL_F_TLS_COLLECT_EXTENSIONS, ERR_R_INTERNAL_ERROR); - goto err; - } + if (thisex != NULL) { + thisex->data = extension; + thisex->present = 1; + thisex->type = type; } + } - if (PACKET_remaining(packet) != 0) { - *ad = SSL_AD_DECODE_ERROR; - SSLerr(SSL_F_TLS_COLLECT_EXTENSIONS, SSL_R_LENGTH_MISMATCH); - goto err; - } - /* Sort the extensions and make sure there are no duplicates. */ - qsort(raw_extensions, num_extensions, sizeof(*raw_extensions), - compare_extensions); - for (i = 1; i < num_extensions; i++) { - if (raw_extensions[i - 1].type == raw_extensions[i].type) { - *ad = SSL_AD_DECODE_ERROR; + if (init) { + /* + * Initialise all known extensions relevant to this context, + * whether we have found them or not + */ + for (thisexd = ext_defs, i = 0; i < OSSL_NELEM(ext_defs); + i++, thisexd++) { + if (thisexd->init != NULL && (thisexd->context & context) != 0 + && extension_is_relevant(s, thisexd->context, context) + && !thisexd->init(s, context)) { + *al = SSL_AD_INTERNAL_ERROR; goto err; } } } *res = raw_extensions; - *numfound = num_extensions; + if (len != NULL) + *len = num_exts; return 1; err: @@ -375,596 +547,669 @@ int tls_collect_extensions(SSL *s, PACKET *packet, unsigned int context, return 0; } -int tls_parse_all_extensions(SSL *s, int context, RAW_EXTENSION *exts, - size_t numexts, int *al) +/* + * 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. If this is for a + * Certificate message, then we also provide the parser with the relevant + * Certificate |x| and its position in the |chainidx| with 0 being the first + * Certificate. 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, TLSEXT_INDEX idx, int context, + RAW_EXTENSION *exts, X509 *x, size_t chainidx, int *al) { - size_t loop; + RAW_EXTENSION *currext = &exts[idx]; + int (*parser)(SSL *s, PACKET *pkt, unsigned int context, X509 *x, + size_t chainidx, int *al) = NULL; - for (loop = 0; loop < numexts; loop++) { - RAW_EXTENSION *currext = &exts[loop]; - const EXTENSION_DEFINITION *extdef = NULL; - 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, 0, currext->type, - PACKET_data(&currext->data), - PACKET_remaining(&currext->data), - s->tlsext_debug_arg); + if (s->ext.debug_cb) + s->ext.debug_cb(s, !s->server, currext->type, + PACKET_data(&currext->data), + PACKET_remaining(&currext->data), + s->ext.debug_arg); - /* Skip if we've already parsed this extension */ - if (currext->parsed) - continue; + /* Skip if we've already parsed this extension */ + if (currext->parsed) + return 1; - currext->parsed = 1; - - parser = NULL; - if (find_extension_definition(s, currext->type, &extdef)) { - parser = s->server ? extdef->server_parse : extdef->client_parse; - - /* Check if extension is defined for our protocol. If not, skip */ - if ((SSL_IS_DTLS(s) - && (extdef->context & EXT_TLS_IMPLEMENTATION_ONLY) != 0) - || (s->version == SSL3_VERSION - && (extdef->context & EXT_SSL3_ALLOWED) == 0) - || (SSL_IS_TLS13(s) - && (extdef->context & EXT_TLS1_2_AND_BELOW_ONLY) != 0) - || (!SSL_IS_TLS13(s) - && (extdef->context & EXT_TLS1_3_ONLY) != 0)) - continue; - } + currext->parsed = 1; - if (parser == NULL) { - /* - * Could be 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; + if (idx < OSSL_NELEM(ext_defs)) { + /* We are handling a built-in extension */ + const EXTENSION_DEFINITION *extdef = &ext_defs[idx]; - continue; - } + /* Check if extension is defined for our protocol. If not, skip */ + if (!extension_is_relevant(s, extdef->context, context)) + return 1; - if (!parser(s, &currext->data, al)) - return 0; + parser = s->server ? extdef->parse_ctos : extdef->parse_stoc; + + if (parser != NULL) + return parser(s, &currext->data, context, x, chainidx, al); + + /* + * If the parser is NULL we fall through to the custom extension + * processing + */ } + /* Parse custom extensions */ + if (custom_ext_parse(s, context, currext->type, + PACKET_data(&currext->data), + PACKET_remaining(&currext->data), + x, chainidx, al) <= 0) + return 0; + return 1; } /* - * Find a specific extension by |type| in the list |exts| containing |numexts| - * extensions, and the parse it immediately. Returns 1 on success, or 0 on - * failure. If a failure has occurred then |*al| will also be set to the alert - * to be sent. + * Parse all remaining extensions that have not yet been parsed. Also calls the + * finalisation for all extensions at the end if |fin| is nonzero, whether we + * collected them or not. Returns 1 for success or 0 for failure. If we are + * working on a Certificate message then we also pass the Certificate |x| and + * its position in the |chainidx|, with 0 being the first certificate. On + * failure, |*al| is populated with a suitable alert code. */ -int tls_parse_extension(SSL *s, int type, int context, RAW_EXTENSION *exts, - size_t numexts, int *al) +int tls_parse_all_extensions(SSL *s, int context, RAW_EXTENSION *exts, X509 *x, + size_t chainidx, int *al, int fin) { - RAW_EXTENSION *ext = tls_get_extension_by_type(exts, numexts, type); + size_t i, numexts = OSSL_NELEM(ext_defs); + const EXTENSION_DEFINITION *thisexd; - if (ext == NULL) - return 1; + /* Calculate the number of extensions in the extensions list */ + numexts += s->cert->custext.meths_count; - return tls_parse_all_extensions(s, context, ext, 1, al); + /* Parse each extension in turn */ + for (i = 0; i < numexts; i++) { + if (!tls_parse_extension(s, i, context, exts, x, chainidx, al)) + return 0; + } + + if (fin) { + /* + * Finalise all known extensions relevant to this context, + * whether we have found them or not + */ + for (i = 0, thisexd = ext_defs; i < OSSL_NELEM(ext_defs); + i++, thisexd++) { + if (thisexd->final != NULL && (thisexd->context & context) != 0 + && !thisexd->final(s, context, exts[i].present, al)) + return 0; + } + } + + return 1; } +int should_add_extension(SSL *s, unsigned int extctx, unsigned int thisctx, + int max_version) +{ + /* Skip if not relevant for our context */ + if ((extctx & thisctx) == 0) + return 0; + + /* Check if this extension is defined for our protocol. If not, skip */ + if ((SSL_IS_DTLS(s) && (extctx & SSL_EXT_TLS_IMPLEMENTATION_ONLY) != 0) + || (s->version == SSL3_VERSION + && (extctx & SSL_EXT_SSL3_ALLOWED) == 0) + || (SSL_IS_TLS13(s) + && (extctx & SSL_EXT_TLS1_2_AND_BELOW_ONLY) != 0) + || (!SSL_IS_TLS13(s) + && (extctx & SSL_EXT_TLS1_3_ONLY) != 0 + && (thisctx & SSL_EXT_CLIENT_HELLO) == 0) + || ((extctx & SSL_EXT_TLS1_3_ONLY) != 0 + && (thisctx & SSL_EXT_CLIENT_HELLO) != 0 + && (SSL_IS_DTLS(s) || max_version < TLS1_3_VERSION))) + return 0; + + return 1; +} + +/* + * Construct all the extensions relevant to the current |context| and write + * them to |pkt|. If this is an extension for a Certificate in a Certificate + * message, then |x| will be set to the Certificate we are handling, and + * |chainidx| will indicate the position in the chainidx we are processing (with + * 0 being the first in the chain). Returns 1 on success or 0 on failure. If a + * failure occurs then |al| is populated with a suitable alert code. On a + * failure construction stops at the first extension to fail to construct. + */ int tls_construct_extensions(SSL *s, WPACKET *pkt, unsigned int context, - int *al) + X509 *x, size_t chainidx, int *al) { - size_t loop; - int addcustom = 0; + size_t i; + int min_version, max_version = 0, reason, tmpal; + const EXTENSION_DEFINITION *thisexd; + + /* + * 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 + * extensions length bytes to a ClientHello/ServerHello in SSLv3 */ - || ((context & EXT_CLIENT_HELLO) != 0 - && !WPACKET_set_flags(pkt, + || ((context & + (SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_2_SERVER_HELLO)) != 0 + && s->version == SSL3_VERSION + && !WPACKET_set_flags(pkt, WPACKET_FLAGS_ABANDON_ON_ZERO_LENGTH))) { - *al = SSL_AD_INTERNAL_ERROR; SSLerr(SSL_F_TLS_CONSTRUCT_EXTENSIONS, ERR_R_INTERNAL_ERROR); - return 0; + goto err; } - for (loop = 0; loop < OSSL_NELEM(ext_defs); loop++) { - int (*construct)(SSL *s, WPACKET *pkt, int *al); + if ((context & SSL_EXT_CLIENT_HELLO) != 0) { + reason = ssl_get_min_max_version(s, &min_version, &max_version); + if (reason != 0) { + SSLerr(SSL_F_TLS_CONSTRUCT_EXTENSIONS, reason); + goto err; + } + } - /* Skip if not relevant for our context */ - if ((ext_defs[loop].context & context) == 0) - continue; + /* Add custom extensions first */ + if ((context & SSL_EXT_CLIENT_HELLO) != 0) { + /* On the server side with initiase during ClientHello parsing */ + custom_ext_init(&s->cert->custext); + } + if (!custom_ext_add(s, context, pkt, x, chainidx, max_version, &tmpal)) { + SSLerr(SSL_F_TLS_CONSTRUCT_EXTENSIONS, ERR_R_INTERNAL_ERROR); + goto err; + } + + for (i = 0, thisexd = ext_defs; i < OSSL_NELEM(ext_defs); i++, thisexd++) { + EXT_RETURN (*construct)(SSL *s, WPACKET *pkt, unsigned int context, + X509 *x, size_t chainidx, int *al); + EXT_RETURN ret; - construct = s->server ? ext_defs[loop].server_construct - : ext_defs[loop].client_construct; - - /* 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) - || construct == NULL) + /* Skip if not relevant for our context */ + if (!should_add_extension(s, thisexd->context, context, max_version)) continue; - if (!construct(s, pkt, al)) - return 0; - } + construct = s->server ? thisexd->construct_stoc + : thisexd->construct_ctos; - /* Add custom extensions */ - 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 (construct == NULL) + continue; - if (addcustom && !custom_ext_add(s, s->server, pkt, al)) { - SSLerr(SSL_F_TLS_CONSTRUCT_EXTENSIONS, ERR_R_INTERNAL_ERROR); - return 0; + ret = construct(s, pkt, context, x, chainidx, &tmpal); + if (ret == EXT_RETURN_FAIL) + goto err; + if (ret == EXT_RETURN_SENT + && (context & (SSL_EXT_CLIENT_HELLO + | SSL_EXT_TLS1_3_CERTIFICATE_REQUEST + | SSL_EXT_TLS1_3_NEW_SESSION_TICKET)) != 0) + s->ext.extflags[i] |= SSL_EXT_FLAG_SENT; } if (!WPACKET_close(pkt)) { - *al = SSL_AD_INTERNAL_ERROR; SSLerr(SSL_F_TLS_CONSTRUCT_EXTENSIONS, ERR_R_INTERNAL_ERROR); - return 0; + goto err; } return 1; + + err: + *al = tmpal; + return 0; } /* - * Parse the client's renegotiation binding and abort if it's not right + * 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_parse_clienthello_renegotiate(SSL *s, PACKET *pkt, int *al) + +static int final_renegotiate(SSL *s, unsigned int context, int sent, + int *al) { - unsigned int ilen; - const unsigned char *data; - - /* Parse the length byte */ - if (!PACKET_get_1(pkt, &ilen) - || !PACKET_get_bytes(pkt, &data, ilen)) { - SSLerr(SSL_F_TLS_PARSE_CLIENTHELLO_RENEGOTIATE, - SSL_R_RENEGOTIATION_ENCODING_ERR); - *al = SSL_AD_ILLEGAL_PARAMETER; - return 0; - } + 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_FINAL_RENEGOTIATE, + SSL_R_UNSAFE_LEGACY_RENEGOTIATION_DISABLED); + return 0; + } - /* Check that the extension matches */ - if (ilen != s->s3->previous_client_finished_len) { - SSLerr(SSL_F_TLS_PARSE_CLIENTHELLO_RENEGOTIATE, - SSL_R_RENEGOTIATION_MISMATCH); - *al = SSL_AD_HANDSHAKE_FAILURE; - return 0; + return 1; } - if (memcmp(data, s->s3->previous_client_finished, - s->s3->previous_client_finished_len)) { - SSLerr(SSL_F_TLS_PARSE_CLIENTHELLO_RENEGOTIATE, - SSL_R_RENEGOTIATION_MISMATCH); + /* Need RI if renegotiating */ + if (s->renegotiate + && !(s->options & SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION) + && !sent) { *al = SSL_AD_HANDSHAKE_FAILURE; + SSLerr(SSL_F_FINAL_RENEGOTIATE, + SSL_R_UNSAFE_LEGACY_RENEGOTIATION_DISABLED); return 0; } - s->s3->send_connection_binding = 1; return 1; } -static int tls_parse_clienthello_server_name(SSL *s, PACKET *pkt, int *al) +static int init_server_name(SSL *s, unsigned int context) { - unsigned int servname_type; - PACKET sni, hostname; - - /*- - * The servername extension is treated as follows: - * - * - Only the hostname type is supported with a maximum length of 255. - * - The servername is rejected if too long or if it contains zeros, - * in which case an fatal alert is generated. - * - The servername field is maintained together with the session cache. - * - When a session is resumed, the servername call back invoked in order - * to allow the application to position itself to the right context. - * - The servername is acknowledged if it is new for a session or when - * it is identical to a previously used for the same session. - * Applications can control the behaviour. They can at any time - * set a 'desirable' servername for a new SSL object. This can be the - * case for example with HTTPS when a Host: header field is received and - * a renegotiation is requested. In this case, a possible servername - * presented in the new client hello is only acknowledged if it matches - * the value of the Host: field. - * - Applications must use SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION - * if they provide for changing an explicit servername context for the - * session, i.e. when the session has been established with a servername - * extension. - * - On session reconnect, the servername extension may be absent. - * - */ - if (!PACKET_as_length_prefixed_2(pkt, &sni) - /* ServerNameList must be at least 1 byte long. */ - || PACKET_remaining(&sni) == 0) { - *al = SSL_AD_DECODE_ERROR; - return 0; - } + if (s->server) + s->servername_done = 0; - /* - * Although the server_name extension was intended to be - * extensible to new name types, RFC 4366 defined the - * syntax inextensibility and OpenSSL 1.0.x parses it as - * such. - * RFC 6066 corrected the mistake but adding new name types - * is nevertheless no longer feasible, so act as if no other - * SNI types can exist, to simplify parsing. - * - * Also note that the RFC permits only one SNI value per type, - * i.e., we can only have a single hostname. - */ - if (!PACKET_get_1(&sni, &servname_type) - || servname_type != TLSEXT_NAMETYPE_host_name - || !PACKET_as_length_prefixed_2(&sni, &hostname)) { - *al = SSL_AD_DECODE_ERROR; - return 0; - } + return 1; +} - if (!s->hit) { - if (PACKET_remaining(&hostname) > TLSEXT_MAXLEN_host_name) { - *al = TLS1_AD_UNRECOGNIZED_NAME; - return 0; - } +static int 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->ext.servername_cb != 0) + ret = s->ctx->ext.servername_cb(s, &altmp, + s->ctx->ext.servername_arg); + else if (s->session_ctx != NULL + && s->session_ctx->ext.servername_cb != 0) + ret = s->session_ctx->ext.servername_cb(s, &altmp, + s->session_ctx->ext.servername_arg); + + switch (ret) { + case SSL_TLSEXT_ERR_ALERT_FATAL: + *al = altmp; + return 0; - if (PACKET_contains_zero_byte(&hostname)) { - *al = TLS1_AD_UNRECOGNIZED_NAME; - return 0; - } + case SSL_TLSEXT_ERR_ALERT_WARNING: + *al = altmp; + return 1; - if (!PACKET_strndup(&hostname, &s->session->tlsext_hostname)) { - *al = TLS1_AD_INTERNAL_ERROR; - return 0; - } + case SSL_TLSEXT_ERR_NOACK: + s->servername_done = 0; + return 1; - s->servername_done = 1; - } else { - /* - * TODO(openssl-team): if the SNI doesn't match, we MUST - * fall back to a full handshake. - */ - s->servername_done = s->session->tlsext_hostname - && PACKET_equal(&hostname, s->session->tlsext_hostname, - strlen(s->session->tlsext_hostname)); + default: + return 1; } - - return 1; } -#ifndef OPENSSL_NO_SRP -static int tls_parse_clienthello_srp(SSL *s, PACKET *pkt, int *al) +#ifndef OPENSSL_NO_EC +static int final_ec_pt_formats(SSL *s, unsigned int context, int sent, + int *al) { - PACKET srp_I; + unsigned long alg_k, alg_a; - if (!PACKET_as_length_prefixed_1(pkt, &srp_I) - || PACKET_contains_zero_byte(&srp_I)) { - *al = SSL_AD_DECODE_ERROR; - return 0; - } + if (s->server) + return 1; + + alg_k = s->s3->tmp.new_cipher->algorithm_mkey; + alg_a = s->s3->tmp.new_cipher->algorithm_auth; /* - * TODO(openssl-team): currently, we re-authenticate the user - * upon resumption. Instead, we MUST ignore the login. + * 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 (!PACKET_strndup(&srp_I, &s->srp_ctx.login)) { - *al = TLS1_AD_INTERNAL_ERROR; - return 0; + if (s->ext.ecpointformats != NULL + && s->ext.ecpointformats_len > 0 + && s->session->ext.ecpointformats != NULL + && s->session->ext.ecpointformats_len > 0 + && ((alg_k & SSL_kECDHE) || (alg_a & SSL_aECDSA))) { + /* we are using an ECC cipher */ + size_t i; + unsigned char *list = s->session->ext.ecpointformats; + + for (i = 0; i < s->session->ext.ecpointformats_len; i++) { + if (*list++ == TLSEXT_ECPOINTFORMAT_uncompressed) + break; + } + if (i == s->session->ext.ecpointformats_len) { + SSLerr(SSL_F_FINAL_EC_PT_FORMATS, + SSL_R_TLS_INVALID_ECPOINTFORMAT_LIST); + return 0; + } } return 1; } #endif -#ifndef OPENSSL_NO_EC -static int tls_parse_clienthello_ec_pt_formats(SSL *s, PACKET *pkt, int *al) +static int init_session_ticket(SSL *s, unsigned int context) { - PACKET ec_point_format_list; - - if (!PACKET_as_length_prefixed_1(pkt, &ec_point_format_list) - || PACKET_remaining(&ec_point_format_list) == 0) { - *al = SSL_AD_DECODE_ERROR; - return 0; - } - - if (!s->hit) { - if (!PACKET_memdup(&ec_point_format_list, - &s->session->tlsext_ecpointformatlist, - &s->session->tlsext_ecpointformatlist_length)) { - *al = TLS1_AD_INTERNAL_ERROR; - return 0; - } - } + if (!s->server) + s->ext.ticket_expected = 0; return 1; } -#endif /* OPENSSL_NO_EC */ -static int tls_parse_clienthello_session_ticket(SSL *s, PACKET *pkt, int *al) +#ifndef OPENSSL_NO_OCSP +static int init_status_request(SSL *s, unsigned int context) { - if (s->tls_session_ticket_ext_cb && - !s->tls_session_ticket_ext_cb(s, PACKET_data(pkt), - PACKET_remaining(pkt), - s->tls_session_ticket_ext_cb_arg)) { - *al = TLS1_AD_INTERNAL_ERROR; - return 0; + if (s->server) { + s->ext.status_type = TLSEXT_STATUSTYPE_nothing; + } else { + /* + * Ensure we get sensible values passed to tlsext_status_cb in the event + * that we don't receive a status message + */ + OPENSSL_free(s->ext.ocsp.resp); + s->ext.ocsp.resp = NULL; + s->ext.ocsp.resp_len = 0; } return 1; } +#endif -static int tls_parse_clienthello_sig_algs(SSL *s, PACKET *pkt, int *al) +#ifndef OPENSSL_NO_NEXTPROTONEG +static int init_npn(SSL *s, unsigned int context) { - PACKET supported_sig_algs; + s->s3->npn_seen = 0; - if (!PACKET_as_length_prefixed_2(pkt, &supported_sig_algs) - || (PACKET_remaining(&supported_sig_algs) % 2) != 0 - || PACKET_remaining(&supported_sig_algs) == 0) { - *al = SSL_AD_DECODE_ERROR; - return 0; - } + return 1; +} +#endif - if (!s->hit && !tls1_save_sigalgs(s, PACKET_data(&supported_sig_algs), - PACKET_remaining(&supported_sig_algs))) { - *al = TLS1_AD_INTERNAL_ERROR; - return 0; +static int init_alpn(SSL *s, unsigned int context) +{ + OPENSSL_free(s->s3->alpn_selected); + s->s3->alpn_selected = NULL; + s->s3->alpn_selected_len = 0; + if (s->server) { + OPENSSL_free(s->s3->alpn_proposed); + s->s3->alpn_proposed = NULL; + s->s3->alpn_proposed_len = 0; } - return 1; } -static int tls_parse_clienthello_status_request(SSL *s, PACKET *pkt, int *al) +static int final_alpn(SSL *s, unsigned int context, int sent, int *al) { - if (!PACKET_get_1(pkt, (unsigned int *)&s->tlsext_status_type)) { - *al = SSL_AD_DECODE_ERROR; - return 0; - } -#ifndef OPENSSL_NO_OCSP - if (s->tlsext_status_type == TLSEXT_STATUSTYPE_ocsp) { - const unsigned char *ext_data; - PACKET responder_id_list, exts; - if (!PACKET_get_length_prefixed_2 (pkt, &responder_id_list)) { - *al = SSL_AD_DECODE_ERROR; - return 0; - } + const unsigned char *selected = NULL; + unsigned char selected_len = 0; - /* - * We remove any OCSP_RESPIDs from a previous handshake - * to prevent unbounded memory growth - CVE-2016-6304 - */ - sk_OCSP_RESPID_pop_free(s->tlsext_ocsp_ids, OCSP_RESPID_free); - if (PACKET_remaining(&responder_id_list) > 0) { - s->tlsext_ocsp_ids = sk_OCSP_RESPID_new_null(); - if (s->tlsext_ocsp_ids == NULL) { + if (!s->server) + return 1; + + if (s->ctx->ext.alpn_select_cb != NULL && s->s3->alpn_proposed != NULL) { + int r = s->ctx->ext.alpn_select_cb(s, &selected, &selected_len, + s->s3->alpn_proposed, + (unsigned int)s->s3->alpn_proposed_len, + s->ctx->ext.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->npn_seen = 0; +#endif + } else if (r == SSL_TLSEXT_ERR_NOACK) { + /* Behave as if no callback was present. */ + return 1; } else { - s->tlsext_ocsp_ids = NULL; + *al = SSL_AD_NO_APPLICATION_PROTOCOL; + return 0; } + } - while (PACKET_remaining(&responder_id_list) > 0) { - OCSP_RESPID *id; - PACKET responder_id; - const unsigned char *id_data; + return 1; +} - if (!PACKET_get_length_prefixed_2(&responder_id_list, - &responder_id) - || PACKET_remaining(&responder_id) == 0) { - *al = SSL_AD_DECODE_ERROR; - return 0; - } +static int 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; - id_data = PACKET_data(&responder_id); - /* TODO(size_t): Convert d2i_* to size_t */ - id = d2i_OCSP_RESPID(NULL, &id_data, - (int)PACKET_remaining(&responder_id)); - if (id == NULL) { - *al = SSL_AD_DECODE_ERROR; - return 0; - } + return 1; +} - if (id_data != PACKET_end(&responder_id)) { - OCSP_RESPID_free(id); - *al = SSL_AD_DECODE_ERROR; - return 0; - } +#ifndef OPENSSL_NO_SRP +static int init_srp(SSL *s, unsigned int context) +{ + OPENSSL_free(s->srp_ctx.login); + s->srp_ctx.login = NULL; - if (!sk_OCSP_RESPID_push(s->tlsext_ocsp_ids, id)) { - OCSP_RESPID_free(id); - *al = SSL_AD_INTERNAL_ERROR; - return 0; - } - } + return 1; +} +#endif - /* Read in request_extensions */ - if (!PACKET_as_length_prefixed_2(pkt, &exts)) { - *al = SSL_AD_DECODE_ERROR; - return 0; - } +static int init_etm(SSL *s, unsigned int context) +{ + s->ext.use_etm = 0; - if (PACKET_remaining(&exts) > 0) { - ext_data = PACKET_data(&exts); - sk_X509_EXTENSION_pop_free(s->tlsext_ocsp_exts, - X509_EXTENSION_free); - s->tlsext_ocsp_exts = - d2i_X509_EXTENSIONS(NULL, &ext_data, - (int)PACKET_remaining(&exts)); - if (s->tlsext_ocsp_exts == NULL || ext_data != PACKET_end(&exts)) { - *al = SSL_AD_DECODE_ERROR; - return 0; - } - } - } else -#endif - { - /* - * We don't know what to do with any other type so ignore it. - */ - s->tlsext_status_type = -1; - } + return 1; +} + +static int init_ems(SSL *s, unsigned int context) +{ + if (!s->server) + s->s3->flags &= ~TLS1_FLAGS_RECEIVED_EXTMS; return 1; } -#ifndef OPENSSL_NO_NEXTPROTONEG -static int tls_parse_clienthello_npn(SSL *s, PACKET *pkt, int *al) +static int final_ems(SSL *s, unsigned int context, int sent, int *al) { - if (s->s3->tmp.finish_md_len == 0) { - /*- - * We shouldn't accept this extension on a - * renegotiation. - * - * s->new_session will be set on renegotiation, but we - * probably shouldn't rely that it couldn't be set on - * the initial renegotiation too in certain cases (when - * there's some other reason to disallow resuming an - * earlier session -- the current code won't be doing - * anything like that, but this might change). - * - * A valid sign that there's been a previous handshake - * in this connection is if s->s3->tmp.finish_md_len > - * 0. (We are talking about a check that will happen - * in the Hello protocol round, well before a new - * Finished message could have been computed.) + if (!s->server && s->hit) { + /* + * Check extended master secret extension is consistent with + * original session. */ - s->s3->next_proto_neg_seen = 1; + if (!(s->s3->flags & TLS1_FLAGS_RECEIVED_EXTMS) != + !(s->session->flags & SSL_SESS_FLAG_EXTMS)) { + *al = SSL_AD_HANDSHAKE_FAILURE; + SSLerr(SSL_F_FINAL_EMS, SSL_R_INCONSISTENT_EXTMS); + return 0; + } } return 1; } -#endif -/* - * Save the ALPN extension in a ClientHello. - * pkt: the contents of the ALPN extension, not including type and length. - * al: a pointer to the alert value to send in the event of a failure. - * returns: 1 on success, 0 on error. - */ -static int tls_parse_clienthello_alpn(SSL *s, PACKET *pkt, int *al) +static int init_certificate_authorities(SSL *s, unsigned int context) { - PACKET protocol_list, save_protocol_list, protocol; + sk_X509_NAME_pop_free(s->s3->tmp.peer_ca_names, X509_NAME_free); + s->s3->tmp.peer_ca_names = NULL; + return 1; +} - if (s->s3->tmp.finish_md_len != 0) - return 1; +static EXT_RETURN tls_construct_certificate_authorities(SSL *s, WPACKET *pkt, + unsigned int context, + X509 *x, + size_t chainidx, + int *al) +{ + const STACK_OF(X509_NAME) *ca_sk = SSL_get0_CA_list(s); + + if (ca_sk == NULL || sk_X509_NAME_num(ca_sk) == 0) + return EXT_RETURN_NOT_SENT; + + if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_certificate_authorities) + || !WPACKET_start_sub_packet_u16(pkt) + || !construct_ca_names(s, pkt) + || !WPACKET_close(pkt)) { + SSLerr(SSL_F_TLS_CONSTRUCT_CERTIFICATE_AUTHORITIES, + ERR_R_INTERNAL_ERROR); + return EXT_RETURN_FAIL; + } + + return EXT_RETURN_SENT; +} - if (!PACKET_as_length_prefixed_2(pkt, &protocol_list) - || PACKET_remaining(&protocol_list) < 2) { +static int tls_parse_certificate_authorities(SSL *s, PACKET *pkt, + unsigned int context, X509 *x, + size_t chainidx, int *al) +{ + if (!parse_ca_names(s, pkt, al)) + return 0; + if (PACKET_remaining(pkt) != 0) { *al = SSL_AD_DECODE_ERROR; return 0; } + return 1; +} - save_protocol_list = protocol_list; - do { - /* Protocol names can't be empty. */ - if (!PACKET_get_length_prefixed_1(&protocol_list, &protocol) - || PACKET_remaining(&protocol) == 0) { - *al = SSL_AD_DECODE_ERROR; - return 0; - } - } while (PACKET_remaining(&protocol_list) != 0); +#ifndef OPENSSL_NO_SRTP +static int init_srtp(SSL *s, unsigned int context) +{ + if (s->server) + s->srtp_profile = NULL; + + return 1; +} +#endif - if (!PACKET_memdup(&save_protocol_list, - &s->s3->alpn_proposed, &s->s3->alpn_proposed_len)) { - *al = TLS1_AD_INTERNAL_ERROR; +static int final_sig_algs(SSL *s, unsigned int context, int sent, int *al) +{ + if (!sent && SSL_IS_TLS13(s) && !s->hit) { + *al = TLS13_AD_MISSING_EXTENSION; + SSLerr(SSL_F_FINAL_SIG_ALGS, SSL_R_MISSING_SIGALGS_EXTENSION); return 0; } return 1; } -#ifndef OPENSSL_NO_SRTP -static int tls_parse_clienthello_use_srtp(SSL *s, PACKET *pkt, int *al) +#ifndef OPENSSL_NO_EC +static int final_key_share(SSL *s, unsigned int context, int sent, int *al) { - SRTP_PROTECTION_PROFILE *sprof; - STACK_OF(SRTP_PROTECTION_PROFILE) *srvr; - unsigned int ct, mki_len, id; - int i, srtp_pref; - PACKET subpkt; - - /* Ignore this if we have no SRTP profiles */ - if (SSL_get_srtp_profiles(s) == NULL) + if (!SSL_IS_TLS13(s)) return 1; - /* Pull off the length of the cipher suite list and check it is even */ - if (!PACKET_get_net_2(pkt, &ct) - || (ct & 1) != 0 || !PACKET_get_sub_packet(pkt, &subpkt, ct)) { - SSLerr(SSL_F_TLS_PARSE_CLIENTHELLO_USE_SRTP, - SSL_R_BAD_SRTP_PROTECTION_PROFILE_LIST); - *al = SSL_AD_DECODE_ERROR; + /* Nothing to do for key_share in an HRR */ + if ((context & SSL_EXT_TLS1_3_HELLO_RETRY_REQUEST) != 0) + return 1; + + /* + * If + * we are a client + * AND + * we have no key_share + * AND + * (we are not resuming + * OR the kex_mode doesn't allow non key_share resumes) + * THEN + * fail; + */ + if (!s->server + && !sent + && (!s->hit + || (s->ext.psk_kex_mode & TLSEXT_KEX_MODE_FLAG_KE) == 0)) { + /* Nothing left we can do - just fail */ + *al = SSL_AD_MISSING_EXTENSION; + SSLerr(SSL_F_FINAL_KEY_SHARE, SSL_R_NO_SUITABLE_KEY_SHARE); return 0; } + /* + * If + * we are a server + * AND + * we have no key_share + * THEN + * If + * we didn't already send a HelloRetryRequest + * AND + * the client sent a key_share extension + * AND + * (we are not resuming + * OR the kex_mode allows key_share resumes) + * AND + * a shared group exists + * THEN + * send a HelloRetryRequest + * ELSE If + * we are not resuming + * OR + * the kex_mode doesn't allow non key_share resumes + * THEN + * fail; + */ + if (s->server && s->s3->peer_tmp == NULL) { + /* No suitable share */ + if (s->hello_retry_request == 0 && sent + && (!s->hit + || (s->ext.psk_kex_mode & TLSEXT_KEX_MODE_FLAG_KE_DHE) + != 0)) { + const unsigned char *pcurves, *pcurvestmp, *clntcurves; + size_t num_curves, clnt_num_curves, i; + unsigned int group_id = 0; + + /* Check if a shared group exists */ + + /* Get the clients list of supported groups. */ + if (!tls1_get_curvelist(s, 1, &clntcurves, &clnt_num_curves)) { + *al = SSL_AD_INTERNAL_ERROR; + SSLerr(SSL_F_FINAL_KEY_SHARE, ERR_R_INTERNAL_ERROR); + return 0; + } - srvr = SSL_get_srtp_profiles(s); - s->srtp_profile = NULL; - /* Search all profiles for a match initially */ - srtp_pref = sk_SRTP_PROTECTION_PROFILE_num(srvr); + /* Get our list of available groups */ + if (!tls1_get_curvelist(s, 0, &pcurves, &num_curves)) { + *al = SSL_AD_INTERNAL_ERROR; + SSLerr(SSL_F_FINAL_KEY_SHARE, ERR_R_INTERNAL_ERROR); + return 0; + } - while (PACKET_remaining(&subpkt)) { - if (!PACKET_get_net_2(&subpkt, &id)) { - SSLerr(SSL_F_TLS_PARSE_CLIENTHELLO_USE_SRTP, - SSL_R_BAD_SRTP_PROTECTION_PROFILE_LIST); - *al = SSL_AD_DECODE_ERROR; - return 0; - } + /* Find the first group we allow that is also in client's list */ + for (i = 0, pcurvestmp = pcurves; i < num_curves; + i++, pcurvestmp += 2) { + group_id = bytestogroup(pcurvestmp); - /* - * Only look for match in profiles of higher preference than - * current match. - * If no profiles have been have been configured then this - * does nothing. - */ - for (i = 0; i < srtp_pref; i++) { - sprof = sk_SRTP_PROTECTION_PROFILE_value(srvr, i); - if (sprof->id == id) { - s->srtp_profile = sprof; - srtp_pref = i; - break; + if (check_in_list(s, group_id, clntcurves, clnt_num_curves, 1)) + break; + } + + if (i < num_curves) { + /* A shared group exists so send a HelloRetryRequest */ + s->s3->group_id = group_id; + s->hello_retry_request = 1; + return 1; } } + if (!s->hit + || (s->ext.psk_kex_mode & TLSEXT_KEX_MODE_FLAG_KE) == 0) { + /* Nothing left we can do - just fail */ + if (!sent) + *al = SSL_AD_MISSING_EXTENSION; + else + *al = SSL_AD_HANDSHAKE_FAILURE; + SSLerr(SSL_F_FINAL_KEY_SHARE, SSL_R_NO_SUITABLE_KEY_SHARE); + return 0; + } } + /* We have a key_share so don't send any more HelloRetryRequest messages */ + if (s->server) + s->hello_retry_request = 0; + /* - * Now extract the MKI value as a sanity check, but discard it for now + * For a client side resumption with no key_share we need to generate + * the handshake secret (otherwise this is done during key_share + * processing). */ - if (!PACKET_get_1(pkt, &mki_len)) { - SSLerr(SSL_F_TLS_PARSE_CLIENTHELLO_USE_SRTP, - SSL_R_BAD_SRTP_PROTECTION_PROFILE_LIST); - *al = SSL_AD_DECODE_ERROR; - return 0; - } - - if (!PACKET_forward(pkt, mki_len) - || PACKET_remaining(pkt)) { - SSLerr(SSL_F_TLS_PARSE_CLIENTHELLO_USE_SRTP, SSL_R_BAD_SRTP_MKI_VALUE); - *al = SSL_AD_DECODE_ERROR; + if (!sent && !s->server && !tls13_generate_handshake_secret(s, NULL, 0)) { + *al = SSL_AD_INTERNAL_ERROR; + SSLerr(SSL_F_FINAL_KEY_SHARE, ERR_R_INTERNAL_ERROR); return 0; } @@ -972,203 +1217,170 @@ static int tls_parse_clienthello_use_srtp(SSL *s, PACKET *pkt, int *al) } #endif -static int tls_parse_clienthello_etm(SSL *s, PACKET *pkt, int *al) +static int init_psk_kex_modes(SSL *s, unsigned int context) { - if (!(s->options & SSL_OP_NO_ENCRYPT_THEN_MAC)) - s->s3->flags |= TLS1_FLAGS_ENCRYPT_THEN_MAC; - + s->ext.psk_kex_mode = TLSEXT_KEX_MODE_FLAG_NONE; return 1; } -/* - * Checks a list of |groups| to determine if the |group_id| is in it. If it is - * and |checkallow| is 1 then additionally check if the group is allowed to be - * used. Returns 1 if the group is in the list (and allowed if |checkallow| is - * 1) or 0 otherwise. - */ -static int check_in_list(SSL *s, unsigned int group_id, - const unsigned char *groups, size_t num_groups, - int checkallow) +int tls_psk_do_binder(SSL *s, const EVP_MD *md, const unsigned char *msgstart, + size_t binderoffset, const unsigned char *binderin, + unsigned char *binderout, + SSL_SESSION *sess, int sign) { - size_t i; - - if (groups == NULL || num_groups == 0) - return 0; - - for (i = 0; i < num_groups; i++, groups += 2) { - unsigned int share_id = (groups[0] << 8) | (groups[1]); - - if (group_id == share_id - && (!checkallow || tls_curve_allowed(s, groups, - SSL_SECOP_CURVE_CHECK))) { - break; - } + EVP_PKEY *mackey = NULL; + EVP_MD_CTX *mctx = NULL; + unsigned char hash[EVP_MAX_MD_SIZE], binderkey[EVP_MAX_MD_SIZE]; + unsigned char finishedkey[EVP_MAX_MD_SIZE], tmpbinder[EVP_MAX_MD_SIZE]; + const char resumption_label[] = "res binder"; + size_t bindersize, hashsize = EVP_MD_size(md); + int ret = -1; + + /* Generate the early_secret */ + if (!tls13_generate_secret(s, md, NULL, sess->master_key, + sess->master_key_length, + (unsigned char *)&s->early_secret)) { + SSLerr(SSL_F_TLS_PSK_DO_BINDER, ERR_R_INTERNAL_ERROR); + goto err; } - /* If i == num_groups then not in the list */ - return i < num_groups; -} - -/* - * Process a key_share extension received in the ClientHello. |pkt| contains - * the raw PACKET data for the extension. Returns 1 on success or 0 on failure. - * If a failure occurs then |*al| is set to an appropriate alert value. - */ -static int tls_parse_clienthello_key_share(SSL *s, PACKET *pkt, int *al) -{ - unsigned int group_id; - PACKET key_share_list, encoded_pt; - const unsigned char *clntcurves, *srvrcurves; - size_t clnt_num_curves, srvr_num_curves; - int group_nid, found = 0; - unsigned int curve_flags; - - if (s->hit) - return 1; - - /* Sanity check */ - if (s->s3->peer_tmp != NULL) { - *al = SSL_AD_INTERNAL_ERROR; - SSLerr(SSL_F_TLS_PARSE_CLIENTHELLO_KEY_SHARE, ERR_R_INTERNAL_ERROR); - return 0; + /* + * Create the handshake hash for the binder key...the messages so far are + * empty! + */ + mctx = EVP_MD_CTX_new(); + if (mctx == NULL + || EVP_DigestInit_ex(mctx, md, NULL) <= 0 + || EVP_DigestFinal_ex(mctx, hash, NULL) <= 0) { + SSLerr(SSL_F_TLS_PSK_DO_BINDER, ERR_R_INTERNAL_ERROR); + goto err; } - if (!PACKET_as_length_prefixed_2(pkt, &key_share_list)) { - *al = SSL_AD_HANDSHAKE_FAILURE; - SSLerr(SSL_F_TLS_PARSE_CLIENTHELLO_KEY_SHARE, SSL_R_LENGTH_MISMATCH); - return 0; + /* Generate the binder key */ + if (!tls13_hkdf_expand(s, md, s->early_secret, + (unsigned char *)resumption_label, + sizeof(resumption_label) - 1, hash, binderkey, + hashsize)) { + SSLerr(SSL_F_TLS_PSK_DO_BINDER, ERR_R_INTERNAL_ERROR); + goto err; } - /* Get our list of supported curves */ - if (!tls1_get_curvelist(s, 0, &srvrcurves, &srvr_num_curves)) { - *al = SSL_AD_INTERNAL_ERROR; - SSLerr(SSL_F_TLS_PARSE_CLIENTHELLO_KEY_SHARE, ERR_R_INTERNAL_ERROR); - return 0; + /* Generate the finished key */ + if (!tls13_derive_finishedkey(s, md, binderkey, finishedkey, hashsize)) { + SSLerr(SSL_F_TLS_PSK_DO_BINDER, ERR_R_INTERNAL_ERROR); + goto err; } - /* Get the clients list of supported curves */ - if (!tls1_get_curvelist(s, 1, &clntcurves, &clnt_num_curves)) { - *al = SSL_AD_INTERNAL_ERROR; - SSLerr(SSL_F_TLS_PARSE_CLIENTHELLO_KEY_SHARE, ERR_R_INTERNAL_ERROR); - return 0; + if (EVP_DigestInit_ex(mctx, md, NULL) <= 0) { + SSLerr(SSL_F_TLS_PSK_DO_BINDER, ERR_R_INTERNAL_ERROR); + goto err; } - while (PACKET_remaining(&key_share_list) > 0) { - if (!PACKET_get_net_2(&key_share_list, &group_id) - || !PACKET_get_length_prefixed_2(&key_share_list, &encoded_pt) - || PACKET_remaining(&encoded_pt) == 0) { - *al = SSL_AD_HANDSHAKE_FAILURE; - SSLerr(SSL_F_TLS_PARSE_CLIENTHELLO_KEY_SHARE, - SSL_R_LENGTH_MISMATCH); - return 0; + /* + * Get a hash of the ClientHello up to the start of the binders. If we are + * following a HelloRetryRequest then this includes the hash of the first + * ClientHello and the HelloRetryRequest itself. + */ + if (s->hello_retry_request) { + size_t hdatalen; + void *hdata; + + hdatalen = BIO_get_mem_data(s->s3->handshake_buffer, &hdata); + if (hdatalen <= 0) { + SSLerr(SSL_F_TLS_PSK_DO_BINDER, SSL_R_BAD_HANDSHAKE_LENGTH); + goto err; } /* - * If we already found a suitable key_share we loop through the - * rest to verify the structure, but don't process them. + * For servers the handshake buffer data will include the second + * ClientHello - which we don't want - so we need to take that bit off. */ - if (found) - continue; - - /* Check if this share is in supported_groups sent from client */ - if (!check_in_list(s, group_id, clntcurves, clnt_num_curves, 0)) { - *al = SSL_AD_HANDSHAKE_FAILURE; - SSLerr(SSL_F_TLS_PARSE_CLIENTHELLO_KEY_SHARE, SSL_R_BAD_KEY_SHARE); - return 0; - } - - /* Check if this share is for a group we can use */ - if (!check_in_list(s, group_id, srvrcurves, srvr_num_curves, 1)) { - /* Share not suitable */ - continue; - } - - group_nid = tls1_ec_curve_id2nid(group_id, &curve_flags); - - if (group_nid == 0) { - *al = SSL_AD_INTERNAL_ERROR; - SSLerr(SSL_F_TLS_PARSE_CLIENTHELLO_KEY_SHARE, - SSL_R_UNABLE_TO_FIND_ECDH_PARAMETERS); - return 0; - } - - if ((curve_flags & TLS_CURVE_TYPE) == TLS_CURVE_CUSTOM) { - /* Can happen for some curves, e.g. X25519 */ - EVP_PKEY *key = EVP_PKEY_new(); - - if (key == NULL || !EVP_PKEY_set_type(key, group_nid)) { - *al = SSL_AD_INTERNAL_ERROR; - SSLerr(SSL_F_TLS_PARSE_CLIENTHELLO_KEY_SHARE, ERR_R_EVP_LIB); - EVP_PKEY_free(key); - return 0; - } - s->s3->peer_tmp = key; - } else { - /* Set up EVP_PKEY with named curve as parameters */ - EVP_PKEY_CTX *pctx = EVP_PKEY_CTX_new_id(EVP_PKEY_EC, NULL); - if (pctx == NULL - || EVP_PKEY_paramgen_init(pctx) <= 0 - || EVP_PKEY_CTX_set_ec_paramgen_curve_nid(pctx, - group_nid) <= 0 - || EVP_PKEY_paramgen(pctx, &s->s3->peer_tmp) <= 0) { - *al = SSL_AD_INTERNAL_ERROR; - SSLerr(SSL_F_TLS_PARSE_CLIENTHELLO_KEY_SHARE, ERR_R_EVP_LIB); - EVP_PKEY_CTX_free(pctx); - return 0; + if (s->server) { + PACKET hashprefix, msg; + + /* Find how many bytes are left after the first two messages */ + if (!PACKET_buf_init(&hashprefix, hdata, hdatalen) + || !PACKET_forward(&hashprefix, 1) + || !PACKET_get_length_prefixed_3(&hashprefix, &msg) + || !PACKET_forward(&hashprefix, 1) + || !PACKET_get_length_prefixed_3(&hashprefix, &msg)) { + SSLerr(SSL_F_TLS_PSK_DO_BINDER, ERR_R_INTERNAL_ERROR); + goto err; } - EVP_PKEY_CTX_free(pctx); - pctx = NULL; + hdatalen -= PACKET_remaining(&hashprefix); } - s->s3->group_id = group_id; - if (!EVP_PKEY_set1_tls_encodedpoint(s->s3->peer_tmp, - PACKET_data(&encoded_pt), - PACKET_remaining(&encoded_pt))) { - *al = SSL_AD_DECODE_ERROR; - SSLerr(SSL_F_TLS_PARSE_CLIENTHELLO_KEY_SHARE, SSL_R_BAD_ECPOINT); - return 0; + if (EVP_DigestUpdate(mctx, hdata, hdatalen) <= 0) { + SSLerr(SSL_F_TLS_PSK_DO_BINDER, ERR_R_INTERNAL_ERROR); + goto err; } + } - found = 1; + if (EVP_DigestUpdate(mctx, msgstart, binderoffset) <= 0 + || EVP_DigestFinal_ex(mctx, hash, NULL) <= 0) { + SSLerr(SSL_F_TLS_PSK_DO_BINDER, ERR_R_INTERNAL_ERROR); + goto err; } - return 1; -} + mackey = EVP_PKEY_new_mac_key(EVP_PKEY_HMAC, NULL, finishedkey, hashsize); + if (mackey == NULL) { + SSLerr(SSL_F_TLS_PSK_DO_BINDER, ERR_R_INTERNAL_ERROR); + goto err; + } -#ifndef OPENSSL_NO_EC -static int tls_parse_clienthello_supported_groups(SSL *s, PACKET *pkt, int *al) -{ - PACKET supported_groups_list; + if (!sign) + binderout = tmpbinder; - /* Each group is 2 bytes and we must have at least 1. */ - if (!PACKET_as_length_prefixed_2(pkt, &supported_groups_list) - || PACKET_remaining(&supported_groups_list) == 0 - || (PACKET_remaining(&supported_groups_list) % 2) != 0) { - *al = SSL_AD_DECODE_ERROR; - return 0; + bindersize = hashsize; + if (EVP_DigestSignInit(mctx, NULL, md, NULL, mackey) <= 0 + || EVP_DigestSignUpdate(mctx, hash, hashsize) <= 0 + || EVP_DigestSignFinal(mctx, binderout, &bindersize) <= 0 + || bindersize != hashsize) { + SSLerr(SSL_F_TLS_PSK_DO_BINDER, ERR_R_INTERNAL_ERROR); + goto err; } - if (!s->hit - && !PACKET_memdup(&supported_groups_list, - &s->session->tlsext_supportedgroupslist, - &s->session->tlsext_supportedgroupslist_length)) { - *al = SSL_AD_DECODE_ERROR; - return 0; + if (sign) { + ret = 1; + } else { + /* HMAC keys can't do EVP_DigestVerify* - use CRYPTO_memcmp instead */ + ret = (CRYPTO_memcmp(binderin, binderout, hashsize) == 0); } - return 1; + err: + OPENSSL_cleanse(binderkey, sizeof(binderkey)); + OPENSSL_cleanse(finishedkey, sizeof(finishedkey)); + EVP_PKEY_free(mackey); + EVP_MD_CTX_free(mctx); + + return ret; } -#endif -static int tls_parse_clienthello_ems(SSL *s, PACKET *pkt, int *al) +static int final_early_data(SSL *s, unsigned int context, int sent, int *al) { - /* The extension must always be empty */ - if (PACKET_remaining(pkt) != 0) { - *al = SSL_AD_DECODE_ERROR; - return 0; - } + if (!s->server || !sent) + return 1; + + if (s->max_early_data == 0 + || !s->hit + || s->session->ext.tick_identity != 0 + || s->early_data_state != SSL_EARLY_DATA_ACCEPTING + || !s->ext.early_data_ok + || s->hello_retry_request + || s->s3->alpn_selected_len != s->session->ext.alpn_selected_len + || (s->s3->alpn_selected_len > 0 + && memcmp(s->s3->alpn_selected, s->session->ext.alpn_selected, + s->s3->alpn_selected_len) != 0)) { + s->ext.early_data = SSL_EARLY_DATA_REJECTED; + } else { + s->ext.early_data = SSL_EARLY_DATA_ACCEPTED; - s->s3->flags |= TLS1_FLAGS_RECEIVED_EXTMS; + if (!tls13_change_cipher_state(s, + SSL3_CC_EARLY | SSL3_CHANGE_CIPHER_SERVER_READ)) { + *al = SSL_AD_INTERNAL_ERROR; + return 0; + } + } return 1; }