/* * 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 #include #include "../ssl_locl.h" #include "statem_locl.h" int tls_construct_ctos_renegotiate(SSL *s, WPACKET *pkt, X509 *x, size_t chainidx, int *al) { /* Add RI if renegotiating */ if (!s->renegotiate) return 1; if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_renegotiate) || !WPACKET_start_sub_packet_u16(pkt) || !WPACKET_sub_memcpy_u8(pkt, s->s3->previous_client_finished, s->s3->previous_client_finished_len) || !WPACKET_close(pkt)) { SSLerr(SSL_F_TLS_CONSTRUCT_CTOS_RENEGOTIATE, ERR_R_INTERNAL_ERROR); return 0; } return 1; } int tls_construct_ctos_server_name(SSL *s, WPACKET *pkt, X509 *x, size_t chainidx, int *al) { if (s->ext.hostname == NULL) return 1; /* Add TLS extension servername to the Client Hello message */ if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_server_name) /* Sub-packet for server_name extension */ || !WPACKET_start_sub_packet_u16(pkt) /* Sub-packet for servername list (always 1 hostname)*/ || !WPACKET_start_sub_packet_u16(pkt) || !WPACKET_put_bytes_u8(pkt, TLSEXT_NAMETYPE_host_name) || !WPACKET_sub_memcpy_u16(pkt, s->ext.hostname, strlen(s->ext.hostname)) || !WPACKET_close(pkt) || !WPACKET_close(pkt)) { SSLerr(SSL_F_TLS_CONSTRUCT_CTOS_SERVER_NAME, ERR_R_INTERNAL_ERROR); return 0; } return 1; } #ifndef OPENSSL_NO_SRP int tls_construct_ctos_srp(SSL *s, WPACKET *pkt, X509 *x, size_t chainidx, int *al) { /* Add SRP username if there is one */ if (s->srp_ctx.login == NULL) return 1; if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_srp) /* Sub-packet for SRP extension */ || !WPACKET_start_sub_packet_u16(pkt) || !WPACKET_start_sub_packet_u8(pkt) /* login must not be zero...internal error if so */ || !WPACKET_set_flags(pkt, WPACKET_FLAGS_NON_ZERO_LENGTH) || !WPACKET_memcpy(pkt, s->srp_ctx.login, strlen(s->srp_ctx.login)) || !WPACKET_close(pkt) || !WPACKET_close(pkt)) { SSLerr(SSL_F_TLS_CONSTRUCT_CTOS_SRP, ERR_R_INTERNAL_ERROR); return 0; } return 1; } #endif #ifndef OPENSSL_NO_EC static int use_ecc(SSL *s) { int i, end; unsigned long alg_k, alg_a; STACK_OF(SSL_CIPHER) *cipher_stack = NULL; /* See if we support any ECC ciphersuites */ if (s->version == SSL3_VERSION) return 0; cipher_stack = SSL_get_ciphers(s); end = sk_SSL_CIPHER_num(cipher_stack); for (i = 0; i < end; i++) { const SSL_CIPHER *c = sk_SSL_CIPHER_value(cipher_stack, i); alg_k = c->algorithm_mkey; alg_a = c->algorithm_auth; if ((alg_k & (SSL_kECDHE | SSL_kECDHEPSK)) || (alg_a & SSL_aECDSA) || c->min_tls >= TLS1_3_VERSION) break; } return i < end; } int tls_construct_ctos_ec_pt_formats(SSL *s, WPACKET *pkt, X509 *x, size_t chainidx, int *al) { const unsigned char *pformats; size_t num_formats; if (!use_ecc(s)) return 1; /* Add TLS extension ECPointFormats to the ClientHello message */ tls1_get_formatlist(s, &pformats, &num_formats); if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_ec_point_formats) /* Sub-packet for formats extension */ || !WPACKET_start_sub_packet_u16(pkt) || !WPACKET_sub_memcpy_u8(pkt, pformats, num_formats) || !WPACKET_close(pkt)) { SSLerr(SSL_F_TLS_CONSTRUCT_CTOS_EC_PT_FORMATS, ERR_R_INTERNAL_ERROR); return 0; } return 1; } int tls_construct_ctos_supported_groups(SSL *s, WPACKET *pkt, X509 *x, size_t chainidx, int *al) { const unsigned char *pcurves = NULL, *pcurvestmp; size_t num_curves = 0, i; if (!use_ecc(s)) return 1; /* * Add TLS extension supported_groups to the ClientHello message */ /* TODO(TLS1.3): Add support for DHE groups */ pcurves = s->ext.supportedgroups; if (!tls1_get_curvelist(s, 0, &pcurves, &num_curves)) { SSLerr(SSL_F_TLS_CONSTRUCT_CTOS_SUPPORTED_GROUPS, ERR_R_INTERNAL_ERROR); return 0; } pcurvestmp = pcurves; if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_supported_groups) /* Sub-packet for supported_groups extension */ || !WPACKET_start_sub_packet_u16(pkt) || !WPACKET_start_sub_packet_u16(pkt)) { SSLerr(SSL_F_TLS_CONSTRUCT_CTOS_SUPPORTED_GROUPS, ERR_R_INTERNAL_ERROR); return 0; } /* Copy curve ID if supported */ for (i = 0; i < num_curves; i++, pcurvestmp += 2) { if (tls_curve_allowed(s, pcurves, SSL_SECOP_CURVE_SUPPORTED)) { if (!WPACKET_put_bytes_u8(pkt, pcurvestmp[0]) || !WPACKET_put_bytes_u8(pkt, pcurvestmp[1])) { SSLerr(SSL_F_TLS_CONSTRUCT_CTOS_SUPPORTED_GROUPS, ERR_R_INTERNAL_ERROR); return 0; } } } if (!WPACKET_close(pkt) || !WPACKET_close(pkt)) { SSLerr(SSL_F_TLS_CONSTRUCT_CTOS_SUPPORTED_GROUPS, ERR_R_INTERNAL_ERROR); return 0; } return 1; } #endif int tls_construct_ctos_session_ticket(SSL *s, WPACKET *pkt, X509 *x, size_t chainidx, int *al) { size_t ticklen; if (!tls_use_ticket(s)) return 1; if (!s->new_session && s->session != NULL && s->session->ext.tick != NULL) { ticklen = s->session->ext.ticklen; } else if (s->session && s->ext.session_ticket != NULL && s->ext.session_ticket->data != NULL) { ticklen = s->ext.session_ticket->length; s->session->ext.tick = OPENSSL_malloc(ticklen); if (s->session->ext.tick == NULL) { SSLerr(SSL_F_TLS_CONSTRUCT_CTOS_SESSION_TICKET, ERR_R_INTERNAL_ERROR); return 0; } memcpy(s->session->ext.tick, s->ext.session_ticket->data, ticklen); s->session->ext.ticklen = ticklen; } else { ticklen = 0; } if (ticklen == 0 && s->ext.session_ticket != NULL && s->ext.session_ticket->data == NULL) return 1; if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_session_ticket) || !WPACKET_sub_memcpy_u16(pkt, s->session->ext.tick, ticklen)) { SSLerr(SSL_F_TLS_CONSTRUCT_CTOS_SESSION_TICKET, ERR_R_INTERNAL_ERROR); return 0; } return 1; } int tls_construct_ctos_sig_algs(SSL *s, WPACKET *pkt, X509 *x, size_t chainidx, int *al) { size_t salglen; const unsigned int *salg; if (!SSL_CLIENT_USE_SIGALGS(s)) return 1; salglen = tls12_get_psigalgs(s, 1, &salg); if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_signature_algorithms) /* Sub-packet for sig-algs extension */ || !WPACKET_start_sub_packet_u16(pkt) /* Sub-packet for the actual list */ || !WPACKET_start_sub_packet_u16(pkt) || !tls12_copy_sigalgs(s, pkt, salg, salglen) || !WPACKET_close(pkt) || !WPACKET_close(pkt)) { SSLerr(SSL_F_TLS_CONSTRUCT_CTOS_SIG_ALGS, ERR_R_INTERNAL_ERROR); return 0; } return 1; } #ifndef OPENSSL_NO_OCSP int tls_construct_ctos_status_request(SSL *s, WPACKET *pkt, X509 *x, size_t chainidx, int *al) { int i; /* This extension isn't defined for client Certificates */ if (x != NULL) return 1; if (s->ext.status_type != TLSEXT_STATUSTYPE_ocsp) return 1; if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_status_request) /* Sub-packet for status request extension */ || !WPACKET_start_sub_packet_u16(pkt) || !WPACKET_put_bytes_u8(pkt, TLSEXT_STATUSTYPE_ocsp) /* Sub-packet for the ids */ || !WPACKET_start_sub_packet_u16(pkt)) { SSLerr(SSL_F_TLS_CONSTRUCT_CTOS_STATUS_REQUEST, ERR_R_INTERNAL_ERROR); return 0; } for (i = 0; i < sk_OCSP_RESPID_num(s->ext.ocsp.ids); i++) { unsigned char *idbytes; OCSP_RESPID *id = sk_OCSP_RESPID_value(s->ext.ocsp.ids, i); int idlen = i2d_OCSP_RESPID(id, NULL); if (idlen <= 0 /* Sub-packet for an individual id */ || !WPACKET_sub_allocate_bytes_u16(pkt, idlen, &idbytes) || i2d_OCSP_RESPID(id, &idbytes) != idlen) { SSLerr(SSL_F_TLS_CONSTRUCT_CTOS_STATUS_REQUEST, ERR_R_INTERNAL_ERROR); return 0; } } if (!WPACKET_close(pkt) || !WPACKET_start_sub_packet_u16(pkt)) { SSLerr(SSL_F_TLS_CONSTRUCT_CTOS_STATUS_REQUEST, ERR_R_INTERNAL_ERROR); return 0; } if (s->ext.ocsp.exts) { unsigned char *extbytes; int extlen = i2d_X509_EXTENSIONS(s->ext.ocsp.exts, NULL); if (extlen < 0) { SSLerr(SSL_F_TLS_CONSTRUCT_CTOS_STATUS_REQUEST, ERR_R_INTERNAL_ERROR); return 0; } if (!WPACKET_allocate_bytes(pkt, extlen, &extbytes) || i2d_X509_EXTENSIONS(s->ext.ocsp.exts, &extbytes) != extlen) { SSLerr(SSL_F_TLS_CONSTRUCT_CTOS_STATUS_REQUEST, ERR_R_INTERNAL_ERROR); return 0; } } if (!WPACKET_close(pkt) || !WPACKET_close(pkt)) { SSLerr(SSL_F_TLS_CONSTRUCT_CTOS_STATUS_REQUEST, ERR_R_INTERNAL_ERROR); return 0; } return 1; } #endif #ifndef OPENSSL_NO_NEXTPROTONEG int tls_construct_ctos_npn(SSL *s, WPACKET *pkt, X509 *x, size_t chainidx, int *al) { if (s->ctx->ext.npn_select_cb == NULL || !SSL_IS_FIRST_HANDSHAKE(s)) return 1; /* * The client advertises an empty extension to indicate its support * for Next Protocol Negotiation */ if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_next_proto_neg) || !WPACKET_put_bytes_u16(pkt, 0)) { SSLerr(SSL_F_TLS_CONSTRUCT_CTOS_NPN, ERR_R_INTERNAL_ERROR); return 0; } return 1; } #endif int tls_construct_ctos_alpn(SSL *s, WPACKET *pkt, X509 *x, size_t chainidx, int *al) { s->s3->alpn_sent = 0; if (s->ext.alpn == NULL || !SSL_IS_FIRST_HANDSHAKE(s)) return 1; if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_application_layer_protocol_negotiation) /* Sub-packet ALPN extension */ || !WPACKET_start_sub_packet_u16(pkt) || !WPACKET_sub_memcpy_u16(pkt, s->ext.alpn, s->ext.alpn_len) || !WPACKET_close(pkt)) { SSLerr(SSL_F_TLS_CONSTRUCT_CTOS_ALPN, ERR_R_INTERNAL_ERROR); return 0; } s->s3->alpn_sent = 1; return 1; } #ifndef OPENSSL_NO_SRTP int tls_construct_ctos_use_srtp(SSL *s, WPACKET *pkt, X509 *x, size_t chainidx, int *al) { STACK_OF(SRTP_PROTECTION_PROFILE) *clnt = SSL_get_srtp_profiles(s); int i, end; if (clnt == NULL) return 1; if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_use_srtp) /* Sub-packet for SRTP extension */ || !WPACKET_start_sub_packet_u16(pkt) /* Sub-packet for the protection profile list */ || !WPACKET_start_sub_packet_u16(pkt)) { SSLerr(SSL_F_TLS_CONSTRUCT_CTOS_USE_SRTP, ERR_R_INTERNAL_ERROR); return 0; } end = sk_SRTP_PROTECTION_PROFILE_num(clnt); for (i = 0; i < end; i++) { const SRTP_PROTECTION_PROFILE *prof = sk_SRTP_PROTECTION_PROFILE_value(clnt, i); if (prof == NULL || !WPACKET_put_bytes_u16(pkt, prof->id)) { SSLerr(SSL_F_TLS_CONSTRUCT_CTOS_USE_SRTP, ERR_R_INTERNAL_ERROR); return 0; } } if (!WPACKET_close(pkt) /* Add an empty use_mki value */ || !WPACKET_put_bytes_u8(pkt, 0) || !WPACKET_close(pkt)) { SSLerr(SSL_F_TLS_CONSTRUCT_CTOS_USE_SRTP, ERR_R_INTERNAL_ERROR); return 0; } return 1; } #endif int tls_construct_ctos_etm(SSL *s, WPACKET *pkt, X509 *x, size_t chainidx, int *al) { if (s->options & SSL_OP_NO_ENCRYPT_THEN_MAC) return 1; if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_encrypt_then_mac) || !WPACKET_put_bytes_u16(pkt, 0)) { SSLerr(SSL_F_TLS_CONSTRUCT_CTOS_ETM, ERR_R_INTERNAL_ERROR); return 0; } return 1; } #ifndef OPENSSL_NO_CT int tls_construct_ctos_sct(SSL *s, WPACKET *pkt, X509 *x, size_t chainidx, int *al) { if (s->ct_validation_callback == NULL) return 1; /* Not defined for client Certificates */ if (x != NULL) return 1; if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_signed_certificate_timestamp) || !WPACKET_put_bytes_u16(pkt, 0)) { SSLerr(SSL_F_TLS_CONSTRUCT_CTOS_SCT, ERR_R_INTERNAL_ERROR); return 0; } return 1; } #endif int tls_construct_ctos_ems(SSL *s, WPACKET *pkt, X509 *x, size_t chainidx, int *al) { if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_extended_master_secret) || !WPACKET_put_bytes_u16(pkt, 0)) { SSLerr(SSL_F_TLS_CONSTRUCT_CTOS_EMS, ERR_R_INTERNAL_ERROR); return 0; } return 1; } int tls_construct_ctos_supported_versions(SSL *s, WPACKET *pkt, X509 *x, size_t chainidx, int *al) { int currv, min_version, max_version, reason; if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_supported_versions) || !WPACKET_start_sub_packet_u16(pkt) || !WPACKET_start_sub_packet_u8(pkt)) { SSLerr(SSL_F_TLS_CONSTRUCT_CTOS_SUPPORTED_VERSIONS, ERR_R_INTERNAL_ERROR); return 0; } reason = ssl_get_client_min_max_version(s, &min_version, &max_version); if (reason != 0) { SSLerr(SSL_F_TLS_CONSTRUCT_CTOS_SUPPORTED_VERSIONS, reason); return 0; } /* * TODO(TLS1.3): There is some discussion on the TLS list as to wheter * we should include versions = min_version; currv--) { /* TODO(TLS1.3): Remove this first if clause prior to release!! */ if (currv == TLS1_3_VERSION) { if (!WPACKET_put_bytes_u16(pkt, TLS1_3_VERSION_DRAFT)) { SSLerr(SSL_F_TLS_CONSTRUCT_CTOS_SUPPORTED_VERSIONS, ERR_R_INTERNAL_ERROR); return 0; } } else if (!WPACKET_put_bytes_u16(pkt, currv)) { SSLerr(SSL_F_TLS_CONSTRUCT_CTOS_SUPPORTED_VERSIONS, ERR_R_INTERNAL_ERROR); return 0; } } if (!WPACKET_close(pkt) || !WPACKET_close(pkt)) { SSLerr(SSL_F_TLS_CONSTRUCT_CTOS_SUPPORTED_VERSIONS, ERR_R_INTERNAL_ERROR); return 0; } return 1; } /* * Construct a psk_kex_modes extension. We only have two modes we know about * at this stage, so we send both. */ int tls_construct_ctos_psk_kex_modes(SSL *s, WPACKET *pkt, X509 *x, size_t chainidx, int *al) { #ifndef OPENSSL_NO_TLS1_3 /* * TODO(TLS1.3): Do we want this list to be configurable? For now we always * just send both supported modes */ if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_psk_kex_modes) || !WPACKET_start_sub_packet_u16(pkt) || !WPACKET_start_sub_packet_u8(pkt) || !WPACKET_put_bytes_u8(pkt, TLSEXT_KEX_MODE_KE_DHE) || !WPACKET_put_bytes_u8(pkt, TLSEXT_KEX_MODE_KE) || !WPACKET_close(pkt) || !WPACKET_close(pkt)) { SSLerr(SSL_F_TLS_CONSTRUCT_CTOS_PSK_KEX_MODES, ERR_R_INTERNAL_ERROR); return 0; } #endif return 1; } int tls_construct_ctos_key_share(SSL *s, WPACKET *pkt, X509 *x, size_t chainidx, int *al) { #ifndef OPENSSL_NO_TLS1_3 size_t i, sharessent = 0, num_curves = 0; const unsigned char *pcurves = NULL; /* key_share extension */ if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_key_share) /* Extension data sub-packet */ || !WPACKET_start_sub_packet_u16(pkt) /* KeyShare list sub-packet */ || !WPACKET_start_sub_packet_u16(pkt)) { SSLerr(SSL_F_TLS_CONSTRUCT_CTOS_KEY_SHARE, ERR_R_INTERNAL_ERROR); return 0; } pcurves = s->ext.supportedgroups; if (!tls1_get_curvelist(s, 0, &pcurves, &num_curves)) { SSLerr(SSL_F_TLS_CONSTRUCT_CTOS_KEY_SHARE, ERR_R_INTERNAL_ERROR); return 0; } /* * TODO(TLS1.3): Make the number of key_shares sent configurable. For * now, just send one */ for (i = 0; i < num_curves && sharessent < 1; i++, pcurves += 2) { unsigned char *encodedPoint = NULL; unsigned int curve_id = 0; EVP_PKEY *key_share_key = NULL; size_t encodedlen; if (!tls_curve_allowed(s, pcurves, SSL_SECOP_CURVE_SUPPORTED)) continue; if (s->s3->tmp.pkey != NULL) { /* Shouldn't happen! */ SSLerr(SSL_F_TLS_CONSTRUCT_CTOS_KEY_SHARE, ERR_R_INTERNAL_ERROR); return 0; } /* Generate a key for this key_share */ curve_id = (pcurves[0] << 8) | pcurves[1]; key_share_key = ssl_generate_pkey_curve(curve_id); if (key_share_key == NULL) { SSLerr(SSL_F_TLS_CONSTRUCT_CTOS_KEY_SHARE, ERR_R_EVP_LIB); return 0; } /* Encode the public key. */ encodedlen = EVP_PKEY_get1_tls_encodedpoint(key_share_key, &encodedPoint); if (encodedlen == 0) { SSLerr(SSL_F_TLS_CONSTRUCT_CTOS_KEY_SHARE, ERR_R_EC_LIB); EVP_PKEY_free(key_share_key); return 0; } /* Create KeyShareEntry */ if (!WPACKET_put_bytes_u16(pkt, curve_id) || !WPACKET_sub_memcpy_u16(pkt, encodedPoint, encodedlen)) { SSLerr(SSL_F_TLS_CONSTRUCT_CTOS_KEY_SHARE, ERR_R_INTERNAL_ERROR); EVP_PKEY_free(key_share_key); OPENSSL_free(encodedPoint); return 0; } /* * TODO(TLS1.3): When changing to send more than one key_share we're * going to need to be able to save more than one EVP_PKEY. For now * we reuse the existing tmp.pkey */ s->s3->group_id = curve_id; s->s3->tmp.pkey = key_share_key; sharessent++; OPENSSL_free(encodedPoint); } if (!WPACKET_close(pkt) || !WPACKET_close(pkt)) { SSLerr(SSL_F_TLS_CONSTRUCT_CTOS_KEY_SHARE, ERR_R_INTERNAL_ERROR); return 0; } #endif return 1; } #define F5_WORKAROUND_MIN_MSG_LEN 0xff #define F5_WORKAROUND_MAX_MSG_LEN 0x200 int tls_construct_ctos_padding(SSL *s, WPACKET *pkt, X509 *x, size_t chainidx, int *al) { unsigned char *padbytes; size_t hlen; if ((s->options & SSL_OP_TLSEXT_PADDING) == 0) return 1; /* * Add padding to workaround bugs in F5 terminators. See * https://tools.ietf.org/html/draft-agl-tls-padding-03 NB: because this * code calculates the length of all existing extensions it MUST always * appear last. */ if (!WPACKET_get_total_written(pkt, &hlen)) { SSLerr(SSL_F_TLS_CONSTRUCT_CTOS_PADDING, ERR_R_INTERNAL_ERROR); return 0; } if (hlen > F5_WORKAROUND_MIN_MSG_LEN && hlen < F5_WORKAROUND_MAX_MSG_LEN) { /* Calculate the amond of padding we need to add */ hlen = F5_WORKAROUND_MAX_MSG_LEN - hlen; /* * Take off the size of extension header itself (2 bytes for type and * 2 bytes for length bytes) */ if (hlen >= 4) hlen -= 4; else hlen = 0; if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_padding) || !WPACKET_sub_allocate_bytes_u16(pkt, hlen, &padbytes)) { SSLerr(SSL_F_TLS_CONSTRUCT_CTOS_PADDING, ERR_R_INTERNAL_ERROR); return 0; } memset(padbytes, 0, hlen); } return 1; } /* * Construct the pre_shared_key extension */ int tls_construct_ctos_psk(SSL *s, WPACKET *pkt, X509 *x, size_t chainidx, int *al) { #ifndef OPENSSL_NO_TLS1_3 const SSL_CIPHER *cipher; uint32_t now, ages, agems; size_t hashsize, bindersize, binderoffset, msglen; unsigned char *binder = NULL, *msgstart = NULL; EVP_PKEY *mackey = NULL; const EVP_MD *md; EVP_MD_CTX *mctx = NULL; unsigned char hash[EVP_MAX_MD_SIZE], binderkey[EVP_MAX_MD_SIZE]; unsigned char finishedkey[EVP_MAX_MD_SIZE]; const char resumption_label[] = "resumption psk binder key"; int ret = 0; s->session->ext.tick_identity = TLSEXT_PSK_BAD_IDENTITY; /* * If this is a new session then we have nothing to resume so don't add * this extension. */ if (s->session->ext.ticklen == 0) return 1; /* * Technically the C standard just says time() returns a time_t and says * nothing about the encoding of that type. In practice most implementations * follow POSIX which holds it as an integral type in seconds since epoch. * We've already made the assumption that we can do this in multiple places * in the code, so portability shouldn't be an issue. */ now = (uint32_t)time(NULL); ages = now - (uint32_t)s->session->time; /* * Calculate age in ms. We're just doing it to nearest second. Should be * good enough. */ agems = ages * (uint32_t)1000; if (ages != 0 && agems / (uint32_t)1000 != ages) { /* * Overflow. Shouldn't happen unless this is a *really* old session. If * so we just ignore it. */ return 1; } /* TODO(TLS1.3): Obfuscate the age here */ cipher = ssl3_get_cipher_by_id(s->session->cipher_id); if (cipher == NULL) { /* Don't recognise this cipher so we can't use the session. Ignore it */ return 1; } md = ssl_md(cipher->algorithm2); if (md == NULL) { /* Shouldn't happen!! */ SSLerr(SSL_F_TLS_CONSTRUCT_CTOS_PSK, ERR_R_INTERNAL_ERROR); return 0; } hashsize = EVP_MD_size(md); /* Create the extension, but skip over the binder for now */ if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_psk) || !WPACKET_start_sub_packet_u16(pkt) || !WPACKET_start_sub_packet_u16(pkt) || !WPACKET_sub_memcpy_u16(pkt, s->session->ext.tick, s->session->ext.ticklen) || !WPACKET_put_bytes_u32(pkt, agems) || !WPACKET_close(pkt) || !WPACKET_get_total_written(pkt, &binderoffset) || !WPACKET_start_sub_packet_u16(pkt) || !WPACKET_sub_allocate_bytes_u8(pkt, hashsize, &binder) || !WPACKET_close(pkt) || !WPACKET_close(pkt) || !WPACKET_get_total_written(pkt, &msglen) /* * We need to fill in all the sub-packet lengths now so we can * calculate the HMAC of the message up to the binders */ || !WPACKET_fill_lengths(pkt)) { SSLerr(SSL_F_TLS_CONSTRUCT_CTOS_PSK, ERR_R_INTERNAL_ERROR); goto err; } msgstart = WPACKET_get_curr(pkt) - msglen; /* Generate the early_secret */ if (!tls13_generate_secret(s, md, NULL, s->session->master_key, s->session->master_key_length, (unsigned char *)&s->early_secret)) { SSLerr(SSL_F_TLS_CONSTRUCT_CTOS_PSK, ERR_R_INTERNAL_ERROR); goto err; } /* * 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_CONSTRUCT_CTOS_PSK, ERR_R_INTERNAL_ERROR); goto err; } /* 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_CONSTRUCT_CTOS_PSK, ERR_R_INTERNAL_ERROR); goto err; } /* Generate the finished key */ if (!tls13_derive_finishedkey(s, md, binderkey, finishedkey, hashsize)) { SSLerr(SSL_F_TLS_CONSTRUCT_CTOS_PSK, ERR_R_INTERNAL_ERROR); goto err; } /* * Get a hash of the ClientHello up to the start of the binders. * TODO(TLS1.3): This will need to be tweaked when we implement * HelloRetryRequest to include the digest of the previous messages here. */ if (EVP_DigestInit_ex(mctx, md, NULL) <= 0 || EVP_DigestUpdate(mctx, msgstart, binderoffset) <= 0 || EVP_DigestFinal_ex(mctx, hash, NULL) <= 0) { SSLerr(SSL_F_TLS_CONSTRUCT_CTOS_PSK, ERR_R_INTERNAL_ERROR); goto err; } mackey = EVP_PKEY_new_mac_key(EVP_PKEY_HMAC, NULL, finishedkey, hashsize); bindersize = hashsize; if (binderkey == NULL || EVP_DigestSignInit(mctx, NULL, md, NULL, mackey) <= 0 || EVP_DigestSignUpdate(mctx, hash, hashsize) <= 0 || EVP_DigestSignFinal(mctx, binder, &bindersize) <= 0 || bindersize != hashsize) { SSLerr(SSL_F_TLS_CONSTRUCT_CTOS_PSK, ERR_R_INTERNAL_ERROR); goto err; } s->session->ext.tick_identity = 0; ret = 1; err: OPENSSL_cleanse(binderkey, sizeof(binderkey)); EVP_PKEY_free(mackey); EVP_MD_CTX_free(mctx); return ret; #else return 1; #endif } /* * Parse the server's renegotiation binding and abort if it's not right */ int tls_parse_stoc_renegotiate(SSL *s, PACKET *pkt, X509 *x, size_t chainidx, int *al) { size_t expected_len = s->s3->previous_client_finished_len + s->s3->previous_server_finished_len; size_t ilen; const unsigned char *data; /* Check for logic errors */ assert(expected_len == 0 || s->s3->previous_client_finished_len != 0); assert(expected_len == 0 || s->s3->previous_server_finished_len != 0); /* Parse the length byte */ if (!PACKET_get_1_len(pkt, &ilen)) { SSLerr(SSL_F_TLS_PARSE_STOC_RENEGOTIATE, SSL_R_RENEGOTIATION_ENCODING_ERR); *al = SSL_AD_ILLEGAL_PARAMETER; return 0; } /* Consistency check */ if (PACKET_remaining(pkt) != ilen) { SSLerr(SSL_F_TLS_PARSE_STOC_RENEGOTIATE, SSL_R_RENEGOTIATION_ENCODING_ERR); *al = SSL_AD_ILLEGAL_PARAMETER; return 0; } /* Check that the extension matches */ if (ilen != expected_len) { SSLerr(SSL_F_TLS_PARSE_STOC_RENEGOTIATE, SSL_R_RENEGOTIATION_MISMATCH); *al = SSL_AD_HANDSHAKE_FAILURE; return 0; } if (!PACKET_get_bytes(pkt, &data, s->s3->previous_client_finished_len) || memcmp(data, s->s3->previous_client_finished, s->s3->previous_client_finished_len) != 0) { SSLerr(SSL_F_TLS_PARSE_STOC_RENEGOTIATE, SSL_R_RENEGOTIATION_MISMATCH); *al = SSL_AD_HANDSHAKE_FAILURE; return 0; } if (!PACKET_get_bytes(pkt, &data, s->s3->previous_server_finished_len) || memcmp(data, s->s3->previous_server_finished, s->s3->previous_server_finished_len) != 0) { SSLerr(SSL_F_TLS_PARSE_STOC_RENEGOTIATE, SSL_R_RENEGOTIATION_MISMATCH); *al = SSL_AD_ILLEGAL_PARAMETER; return 0; } s->s3->send_connection_binding = 1; return 1; } int tls_parse_stoc_server_name(SSL *s, PACKET *pkt, X509 *x, size_t chainidx, int *al) { if (s->ext.hostname == NULL || PACKET_remaining(pkt) > 0) { *al = SSL_AD_UNRECOGNIZED_NAME; return 0; } if (!s->hit) { if (s->session->ext.hostname != NULL) { *al = SSL_AD_INTERNAL_ERROR; return 0; } s->session->ext.hostname = OPENSSL_strdup(s->ext.hostname); if (s->session->ext.hostname == NULL) { *al = SSL_AD_INTERNAL_ERROR; return 0; } } return 1; } #ifndef OPENSSL_NO_EC int tls_parse_stoc_ec_pt_formats(SSL *s, PACKET *pkt, X509 *x, size_t chainidx, int *al) { unsigned int ecpointformats_len; PACKET ecptformatlist; if (!PACKET_as_length_prefixed_1(pkt, &ecptformatlist)) { *al = SSL_AD_DECODE_ERROR; return 0; } if (!s->hit) { ecpointformats_len = PACKET_remaining(&ecptformatlist); s->session->ext.ecpointformats_len = 0; OPENSSL_free(s->session->ext.ecpointformats); s->session->ext.ecpointformats = OPENSSL_malloc(ecpointformats_len); if (s->session->ext.ecpointformats == NULL) { *al = SSL_AD_INTERNAL_ERROR; return 0; } s->session->ext.ecpointformats_len = ecpointformats_len; if (!PACKET_copy_bytes(&ecptformatlist, s->session->ext.ecpointformats, ecpointformats_len)) { *al = SSL_AD_INTERNAL_ERROR; return 0; } } return 1; } #endif int tls_parse_stoc_session_ticket(SSL *s, PACKET *pkt, X509 *x, size_t chainidx, int *al) { if (s->ext.session_ticket_cb != NULL && !s->ext.session_ticket_cb(s, PACKET_data(pkt), PACKET_remaining(pkt), s->ext.session_ticket_cb_arg)) { *al = SSL_AD_INTERNAL_ERROR; return 0; } if (!tls_use_ticket(s) || PACKET_remaining(pkt) > 0) { *al = SSL_AD_UNSUPPORTED_EXTENSION; return 0; } s->ext.ticket_expected = 1; return 1; } #ifndef OPENSSL_NO_OCSP int tls_parse_stoc_status_request(SSL *s, PACKET *pkt, X509 *x, size_t chainidx, int *al) { /* * MUST only be sent if we've requested a status * request message. In TLS <= 1.2 it must also be empty. */ if (s->ext.status_type == TLSEXT_STATUSTYPE_nothing || (!SSL_IS_TLS13(s) && PACKET_remaining(pkt) > 0)) { *al = SSL_AD_UNSUPPORTED_EXTENSION; return 0; } if (SSL_IS_TLS13(s)) { /* We only know how to handle this if it's for the first Certificate in * the chain. We ignore any other repsonses. */ if (chainidx != 0) return 1; return tls_process_cert_status_body(s, pkt, al); } /* Set flag to expect CertificateStatus message */ s->ext.status_expected = 1; return 1; } #endif #ifndef OPENSSL_NO_CT int tls_parse_stoc_sct(SSL *s, PACKET *pkt, X509 *x, size_t chainidx, int *al) { /* * Only take it if we asked for it - i.e if there is no CT validation * callback set, then a custom extension MAY be processing it, so we * need to let control continue to flow to that. */ if (s->ct_validation_callback != NULL) { size_t size = PACKET_remaining(pkt); /* Simply copy it off for later processing */ OPENSSL_free(s->ext.scts); s->ext.scts = NULL; s->ext.scts_len = size; if (size > 0) { s->ext.scts = OPENSSL_malloc(size); if (s->ext.scts == NULL || !PACKET_copy_bytes(pkt, s->ext.scts, size)) { *al = SSL_AD_INTERNAL_ERROR; return 0; } } } else { if (custom_ext_parse(s, 0, TLSEXT_TYPE_signed_certificate_timestamp, PACKET_data(pkt), PACKET_remaining(pkt), al) <= 0) return 0; } return 1; } #endif #ifndef OPENSSL_NO_NEXTPROTONEG /* * ssl_next_proto_validate validates a Next Protocol Negotiation block. No * elements of zero length are allowed and the set of elements must exactly * fill the length of the block. Returns 1 on success or 0 on failure. */ static int ssl_next_proto_validate(PACKET *pkt) { PACKET tmp_protocol; while (PACKET_remaining(pkt)) { if (!PACKET_get_length_prefixed_1(pkt, &tmp_protocol) || PACKET_remaining(&tmp_protocol) == 0) return 0; } return 1; } int tls_parse_stoc_npn(SSL *s, PACKET *pkt, X509 *x, size_t chainidx, int *al) { unsigned char *selected; unsigned char selected_len; PACKET tmppkt; /* Check if we are in a renegotiation. If so ignore this extension */ if (!SSL_IS_FIRST_HANDSHAKE(s)) return 1; /* We must have requested it. */ if (s->ctx->ext.npn_select_cb == NULL) { *al = SSL_AD_UNSUPPORTED_EXTENSION; return 0; } /* The data must be valid */ tmppkt = *pkt; if (!ssl_next_proto_validate(&tmppkt)) { *al = SSL_AD_DECODE_ERROR; return 0; } if (s->ctx->ext.npn_select_cb(s, &selected, &selected_len, PACKET_data(pkt), PACKET_remaining(pkt), s->ctx->ext.npn_select_cb_arg) != SSL_TLSEXT_ERR_OK) { *al = SSL_AD_INTERNAL_ERROR; return 0; } /* * Could be non-NULL if server has sent multiple NPN extensions in * a single Serverhello */ OPENSSL_free(s->ext.npn); s->ext.npn = OPENSSL_malloc(selected_len); if (s->ext.npn == NULL) { *al = SSL_AD_INTERNAL_ERROR; return 0; } memcpy(s->ext.npn, selected, selected_len); s->ext.npn_len = selected_len; s->s3->npn_seen = 1; return 1; } #endif int tls_parse_stoc_alpn(SSL *s, PACKET *pkt, X509 *x, size_t chainidx, int *al) { size_t len; /* We must have requested it. */ if (!s->s3->alpn_sent) { *al = SSL_AD_UNSUPPORTED_EXTENSION; return 0; } /*- * The extension data consists of: * uint16 list_length * uint8 proto_length; * uint8 proto[proto_length]; */ if (!PACKET_get_net_2_len(pkt, &len) || PACKET_remaining(pkt) != len || !PACKET_get_1_len(pkt, &len) || PACKET_remaining(pkt) != len) { *al = SSL_AD_DECODE_ERROR; return 0; } OPENSSL_free(s->s3->alpn_selected); s->s3->alpn_selected = OPENSSL_malloc(len); if (s->s3->alpn_selected == NULL) { *al = SSL_AD_INTERNAL_ERROR; return 0; } if (!PACKET_copy_bytes(pkt, s->s3->alpn_selected, len)) { *al = SSL_AD_DECODE_ERROR; return 0; } s->s3->alpn_selected_len = len; return 1; } #ifndef OPENSSL_NO_SRTP int tls_parse_stoc_use_srtp(SSL *s, PACKET *pkt, X509 *x, size_t chainidx, int *al) { unsigned int id, ct, mki; int i; STACK_OF(SRTP_PROTECTION_PROFILE) *clnt; SRTP_PROTECTION_PROFILE *prof; if (!PACKET_get_net_2(pkt, &ct) || ct != 2 || !PACKET_get_net_2(pkt, &id) || !PACKET_get_1(pkt, &mki) || PACKET_remaining(pkt) != 0) { SSLerr(SSL_F_TLS_PARSE_STOC_USE_SRTP, SSL_R_BAD_SRTP_PROTECTION_PROFILE_LIST); *al = SSL_AD_DECODE_ERROR; return 0; } if (mki != 0) { /* Must be no MKI, since we never offer one */ SSLerr(SSL_F_TLS_PARSE_STOC_USE_SRTP, SSL_R_BAD_SRTP_MKI_VALUE); *al = SSL_AD_ILLEGAL_PARAMETER; return 0; } /* Throw an error if the server gave us an unsolicited extension */ clnt = SSL_get_srtp_profiles(s); if (clnt == NULL) { SSLerr(SSL_F_TLS_PARSE_STOC_USE_SRTP, SSL_R_NO_SRTP_PROFILES); *al = SSL_AD_DECODE_ERROR; return 0; } /* * Check to see if the server gave us something we support (and * presumably offered) */ for (i = 0; i < sk_SRTP_PROTECTION_PROFILE_num(clnt); i++) { prof = sk_SRTP_PROTECTION_PROFILE_value(clnt, i); if (prof->id == id) { s->srtp_profile = prof; *al = 0; return 1; } } SSLerr(SSL_F_TLS_PARSE_STOC_USE_SRTP, SSL_R_BAD_SRTP_PROTECTION_PROFILE_LIST); *al = SSL_AD_DECODE_ERROR; return 0; } #endif int tls_parse_stoc_etm(SSL *s, PACKET *pkt, X509 *x, size_t chainidx, int *al) { /* Ignore if inappropriate ciphersuite */ if (!(s->options & SSL_OP_NO_ENCRYPT_THEN_MAC) && s->s3->tmp.new_cipher->algorithm_mac != SSL_AEAD && s->s3->tmp.new_cipher->algorithm_enc != SSL_RC4) s->s3->flags |= TLS1_FLAGS_ENCRYPT_THEN_MAC; return 1; } int tls_parse_stoc_ems(SSL *s, PACKET *pkt, X509 *x, size_t chainidx, int *al) { s->s3->flags |= TLS1_FLAGS_RECEIVED_EXTMS; if (!s->hit) s->session->flags |= SSL_SESS_FLAG_EXTMS; return 1; } int tls_parse_stoc_key_share(SSL *s, PACKET *pkt, X509 *x, size_t chainidx, int *al) { #ifndef OPENSSL_NO_TLS1_3 unsigned int group_id; PACKET encoded_pt; EVP_PKEY *ckey = s->s3->tmp.pkey, *skey = NULL; /* Sanity check */ if (ckey == NULL) { *al = SSL_AD_INTERNAL_ERROR; SSLerr(SSL_F_TLS_PARSE_STOC_KEY_SHARE, ERR_R_INTERNAL_ERROR); return 0; } if (!PACKET_get_net_2(pkt, &group_id)) { *al = SSL_AD_HANDSHAKE_FAILURE; SSLerr(SSL_F_TLS_PARSE_STOC_KEY_SHARE, SSL_R_LENGTH_MISMATCH); return 0; } if (group_id != s->s3->group_id) { /* * This isn't for the group that we sent in the original * key_share! */ *al = SSL_AD_HANDSHAKE_FAILURE; SSLerr(SSL_F_TLS_PARSE_STOC_KEY_SHARE, SSL_R_BAD_KEY_SHARE); return 0; } if (!PACKET_as_length_prefixed_2(pkt, &encoded_pt) || PACKET_remaining(&encoded_pt) == 0) { *al = SSL_AD_DECODE_ERROR; SSLerr(SSL_F_TLS_PARSE_STOC_KEY_SHARE, SSL_R_LENGTH_MISMATCH); return 0; } skey = ssl_generate_pkey(ckey); if (skey == NULL) { *al = SSL_AD_INTERNAL_ERROR; SSLerr(SSL_F_TLS_PARSE_STOC_KEY_SHARE, ERR_R_MALLOC_FAILURE); return 0; } if (!EVP_PKEY_set1_tls_encodedpoint(skey, PACKET_data(&encoded_pt), PACKET_remaining(&encoded_pt))) { *al = SSL_AD_DECODE_ERROR; SSLerr(SSL_F_TLS_PARSE_STOC_KEY_SHARE, SSL_R_BAD_ECPOINT); EVP_PKEY_free(skey); return 0; } if (ssl_derive(s, ckey, skey, 1) == 0) { *al = SSL_AD_INTERNAL_ERROR; SSLerr(SSL_F_TLS_PARSE_STOC_KEY_SHARE, ERR_R_INTERNAL_ERROR); EVP_PKEY_free(skey); return 0; } EVP_PKEY_free(skey); #endif return 1; }