/* * Copyright 2016-2023 The OpenSSL Project Authors. All Rights Reserved. * * Licensed under the Apache License 2.0 (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 "ssl_local.h" #include "internal/ktls.h" #include "record/record_local.h" #include "internal/cryptlib.h" #include "internal/ssl_unwrap.h" #include #include #include #define TLS13_MAX_LABEL_LEN 249 /* ASCII: "tls13 ", in hex for EBCDIC compatibility */ static const unsigned char label_prefix[] = "\x74\x6C\x73\x31\x33\x20"; /* * Given a |secret|; a |label| of length |labellen|; and |data| of length * |datalen| (e.g. typically a hash of the handshake messages), derive a new * secret |outlen| bytes long and store it in the location pointed to be |out|. * The |data| value may be zero length. Any errors will be treated as fatal if * |fatal| is set. Returns 1 on success 0 on failure. * If |raise_error| is set, ERR_raise is called on failure. */ int tls13_hkdf_expand_ex(OSSL_LIB_CTX *libctx, const char *propq, const EVP_MD *md, const unsigned char *secret, const unsigned char *label, size_t labellen, const unsigned char *data, size_t datalen, unsigned char *out, size_t outlen, int raise_error) { EVP_KDF *kdf = EVP_KDF_fetch(libctx, OSSL_KDF_NAME_TLS1_3_KDF, propq); EVP_KDF_CTX *kctx; OSSL_PARAM params[7], *p = params; int mode = EVP_PKEY_HKDEF_MODE_EXPAND_ONLY; const char *mdname = EVP_MD_get0_name(md); int ret; size_t hashlen; kctx = EVP_KDF_CTX_new(kdf); EVP_KDF_free(kdf); if (kctx == NULL) return 0; if (labellen > TLS13_MAX_LABEL_LEN) { if (raise_error) /* * Probably we have been called from SSL_export_keying_material(), * or SSL_export_keying_material_early(). */ ERR_raise(ERR_LIB_SSL, SSL_R_TLS_ILLEGAL_EXPORTER_LABEL); EVP_KDF_CTX_free(kctx); return 0; } if ((ret = EVP_MD_get_size(md)) <= 0) { EVP_KDF_CTX_free(kctx); if (raise_error) ERR_raise(ERR_LIB_SSL, ERR_R_INTERNAL_ERROR); return 0; } hashlen = (size_t)ret; *p++ = OSSL_PARAM_construct_int(OSSL_KDF_PARAM_MODE, &mode); *p++ = OSSL_PARAM_construct_utf8_string(OSSL_KDF_PARAM_DIGEST, (char *)mdname, 0); *p++ = OSSL_PARAM_construct_octet_string(OSSL_KDF_PARAM_KEY, (unsigned char *)secret, hashlen); *p++ = OSSL_PARAM_construct_octet_string(OSSL_KDF_PARAM_PREFIX, (unsigned char *)label_prefix, sizeof(label_prefix) - 1); *p++ = OSSL_PARAM_construct_octet_string(OSSL_KDF_PARAM_LABEL, (unsigned char *)label, labellen); if (data != NULL) *p++ = OSSL_PARAM_construct_octet_string(OSSL_KDF_PARAM_DATA, (unsigned char *)data, datalen); *p++ = OSSL_PARAM_construct_end(); ret = EVP_KDF_derive(kctx, out, outlen, params) <= 0; EVP_KDF_CTX_free(kctx); if (ret != 0) { if (raise_error) ERR_raise(ERR_LIB_SSL, ERR_R_INTERNAL_ERROR); } return ret == 0; } int tls13_hkdf_expand(SSL_CONNECTION *s, const EVP_MD *md, const unsigned char *secret, const unsigned char *label, size_t labellen, const unsigned char *data, size_t datalen, unsigned char *out, size_t outlen, int fatal) { int ret; SSL_CTX *sctx = SSL_CONNECTION_GET_CTX(s); ret = tls13_hkdf_expand_ex(sctx->libctx, sctx->propq, md, secret, label, labellen, data, datalen, out, outlen, !fatal); if (ret == 0 && fatal) SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); return ret; } /* * Given a |secret| generate a |key| of length |keylen| bytes. Returns 1 on * success 0 on failure. */ int tls13_derive_key(SSL_CONNECTION *s, const EVP_MD *md, const unsigned char *secret, unsigned char *key, size_t keylen) { /* ASCII: "key", in hex for EBCDIC compatibility */ static const unsigned char keylabel[] = "\x6B\x65\x79"; return tls13_hkdf_expand(s, md, secret, keylabel, sizeof(keylabel) - 1, NULL, 0, key, keylen, 1); } /* * Given a |secret| generate an |iv| of length |ivlen| bytes. Returns 1 on * success 0 on failure. */ int tls13_derive_iv(SSL_CONNECTION *s, const EVP_MD *md, const unsigned char *secret, unsigned char *iv, size_t ivlen) { /* ASCII: "iv", in hex for EBCDIC compatibility */ static const unsigned char ivlabel[] = "\x69\x76"; return tls13_hkdf_expand(s, md, secret, ivlabel, sizeof(ivlabel) - 1, NULL, 0, iv, ivlen, 1); } int tls13_derive_finishedkey(SSL_CONNECTION *s, const EVP_MD *md, const unsigned char *secret, unsigned char *fin, size_t finlen) { /* ASCII: "finished", in hex for EBCDIC compatibility */ static const unsigned char finishedlabel[] = "\x66\x69\x6E\x69\x73\x68\x65\x64"; return tls13_hkdf_expand(s, md, secret, finishedlabel, sizeof(finishedlabel) - 1, NULL, 0, fin, finlen, 1); } /* * Given the previous secret |prevsecret| and a new input secret |insecret| of * length |insecretlen|, generate a new secret and store it in the location * pointed to by |outsecret|. Returns 1 on success 0 on failure. */ int tls13_generate_secret(SSL_CONNECTION *s, const EVP_MD *md, const unsigned char *prevsecret, const unsigned char *insecret, size_t insecretlen, unsigned char *outsecret) { size_t mdlen; int mdleni; int ret; EVP_KDF *kdf; EVP_KDF_CTX *kctx; OSSL_PARAM params[7], *p = params; int mode = EVP_PKEY_HKDEF_MODE_EXTRACT_ONLY; const char *mdname = EVP_MD_get0_name(md); /* ASCII: "derived", in hex for EBCDIC compatibility */ static const char derived_secret_label[] = "\x64\x65\x72\x69\x76\x65\x64"; SSL_CTX *sctx = SSL_CONNECTION_GET_CTX(s); kdf = EVP_KDF_fetch(sctx->libctx, OSSL_KDF_NAME_TLS1_3_KDF, sctx->propq); kctx = EVP_KDF_CTX_new(kdf); EVP_KDF_free(kdf); if (kctx == NULL) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); return 0; } mdleni = EVP_MD_get_size(md); /* Ensure cast to size_t is safe */ if (!ossl_assert(mdleni >= 0)) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); EVP_KDF_CTX_free(kctx); return 0; } mdlen = (size_t)mdleni; *p++ = OSSL_PARAM_construct_int(OSSL_KDF_PARAM_MODE, &mode); *p++ = OSSL_PARAM_construct_utf8_string(OSSL_KDF_PARAM_DIGEST, (char *)mdname, 0); if (insecret != NULL) *p++ = OSSL_PARAM_construct_octet_string(OSSL_KDF_PARAM_KEY, (unsigned char *)insecret, insecretlen); if (prevsecret != NULL) *p++ = OSSL_PARAM_construct_octet_string(OSSL_KDF_PARAM_SALT, (unsigned char *)prevsecret, mdlen); *p++ = OSSL_PARAM_construct_octet_string(OSSL_KDF_PARAM_PREFIX, (unsigned char *)label_prefix, sizeof(label_prefix) - 1); *p++ = OSSL_PARAM_construct_octet_string(OSSL_KDF_PARAM_LABEL, (unsigned char *)derived_secret_label, sizeof(derived_secret_label) - 1); *p++ = OSSL_PARAM_construct_end(); ret = EVP_KDF_derive(kctx, outsecret, mdlen, params) <= 0; if (ret != 0) SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); EVP_KDF_CTX_free(kctx); return ret == 0; } /* * Given an input secret |insecret| of length |insecretlen| generate the * handshake secret. This requires the early secret to already have been * generated. Returns 1 on success 0 on failure. */ int tls13_generate_handshake_secret(SSL_CONNECTION *s, const unsigned char *insecret, size_t insecretlen) { /* Calls SSLfatal() if required */ return tls13_generate_secret(s, ssl_handshake_md(s), s->early_secret, insecret, insecretlen, (unsigned char *)&s->handshake_secret); } /* * Given the handshake secret |prev| of length |prevlen| generate the master * secret and store its length in |*secret_size|. Returns 1 on success 0 on * failure. */ int tls13_generate_master_secret(SSL_CONNECTION *s, unsigned char *out, unsigned char *prev, size_t prevlen, size_t *secret_size) { const EVP_MD *md = ssl_handshake_md(s); int md_size; md_size = EVP_MD_get_size(md); if (md_size <= 0) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); return 0; } *secret_size = (size_t)md_size; /* Calls SSLfatal() if required */ return tls13_generate_secret(s, md, prev, NULL, 0, out); } /* * Generates the mac for the Finished message. Returns the length of the MAC or * 0 on error. */ size_t tls13_final_finish_mac(SSL_CONNECTION *s, const char *str, size_t slen, unsigned char *out) { const EVP_MD *md = ssl_handshake_md(s); const char *mdname = EVP_MD_get0_name(md); unsigned char hash[EVP_MAX_MD_SIZE]; unsigned char finsecret[EVP_MAX_MD_SIZE]; unsigned char *key = NULL; size_t len = 0, hashlen; OSSL_PARAM params[2], *p = params; SSL_CTX *sctx = SSL_CONNECTION_GET_CTX(s); if (md == NULL) return 0; /* Safe to cast away const here since we're not "getting" any data */ if (sctx->propq != NULL) *p++ = OSSL_PARAM_construct_utf8_string(OSSL_ALG_PARAM_PROPERTIES, (char *)sctx->propq, 0); *p = OSSL_PARAM_construct_end(); if (!ssl_handshake_hash(s, hash, sizeof(hash), &hashlen)) { /* SSLfatal() already called */ goto err; } if (str == SSL_CONNECTION_GET_SSL(s)->method->ssl3_enc->server_finished_label) { key = s->server_finished_secret; } else if (SSL_IS_FIRST_HANDSHAKE(s)) { key = s->client_finished_secret; } else { if (!tls13_derive_finishedkey(s, md, s->client_app_traffic_secret, finsecret, hashlen)) goto err; key = finsecret; } if (!EVP_Q_mac(sctx->libctx, "HMAC", sctx->propq, mdname, params, key, hashlen, hash, hashlen, /* outsize as per sizeof(peer_finish_md) */ out, EVP_MAX_MD_SIZE * 2, &len)) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); goto err; } err: OPENSSL_cleanse(finsecret, sizeof(finsecret)); return len; } /* * There isn't really a key block in TLSv1.3, but we still need this function * for initialising the cipher and hash. Returns 1 on success or 0 on failure. */ int tls13_setup_key_block(SSL_CONNECTION *s) { const EVP_CIPHER *c; const EVP_MD *hash; s->session->cipher = s->s3.tmp.new_cipher; if (!ssl_cipher_get_evp(SSL_CONNECTION_GET_CTX(s), s->session, &c, &hash, NULL, NULL, NULL, 0)) { /* Error is already recorded */ SSLfatal_alert(s, SSL_AD_INTERNAL_ERROR); return 0; } ssl_evp_cipher_free(s->s3.tmp.new_sym_enc); s->s3.tmp.new_sym_enc = c; ssl_evp_md_free(s->s3.tmp.new_hash); s->s3.tmp.new_hash = hash; return 1; } static int derive_secret_key_and_iv(SSL_CONNECTION *s, const EVP_MD *md, const EVP_CIPHER *ciph, const unsigned char *insecret, const unsigned char *hash, const unsigned char *label, size_t labellen, unsigned char *secret, unsigned char *key, size_t *keylen, unsigned char *iv, size_t *ivlen, size_t *taglen) { int hashleni = EVP_MD_get_size(md); size_t hashlen; int mode; /* Ensure cast to size_t is safe */ if (!ossl_assert(hashleni >= 0)) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_EVP_LIB); return 0; } hashlen = (size_t)hashleni; if (!tls13_hkdf_expand(s, md, insecret, label, labellen, hash, hashlen, secret, hashlen, 1)) { /* SSLfatal() already called */ return 0; } *keylen = EVP_CIPHER_get_key_length(ciph); mode = EVP_CIPHER_get_mode(ciph); if (mode == EVP_CIPH_CCM_MODE) { uint32_t algenc; *ivlen = EVP_CCM_TLS_IV_LEN; if (s->s3.tmp.new_cipher != NULL) { algenc = s->s3.tmp.new_cipher->algorithm_enc; } else if (s->session->cipher != NULL) { /* We've not selected a cipher yet - we must be doing early data */ algenc = s->session->cipher->algorithm_enc; } else if (s->psksession != NULL && s->psksession->cipher != NULL) { /* We must be doing early data with out-of-band PSK */ algenc = s->psksession->cipher->algorithm_enc; } else { SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_EVP_LIB); return 0; } if (algenc & (SSL_AES128CCM8 | SSL_AES256CCM8)) *taglen = EVP_CCM8_TLS_TAG_LEN; else *taglen = EVP_CCM_TLS_TAG_LEN; } else { int iivlen; if (mode == EVP_CIPH_GCM_MODE) { *taglen = EVP_GCM_TLS_TAG_LEN; } else { /* CHACHA20P-POLY1305 */ *taglen = EVP_CHACHAPOLY_TLS_TAG_LEN; } iivlen = EVP_CIPHER_get_iv_length(ciph); if (iivlen < 0) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_EVP_LIB); return 0; } *ivlen = iivlen; } if (!tls13_derive_key(s, md, secret, key, *keylen) || !tls13_derive_iv(s, md, secret, iv, *ivlen)) { /* SSLfatal() already called */ return 0; } return 1; } int tls13_change_cipher_state(SSL_CONNECTION *s, int which) { /* ASCII: "c e traffic", in hex for EBCDIC compatibility */ static const unsigned char client_early_traffic[] = "\x63\x20\x65\x20\x74\x72\x61\x66\x66\x69\x63"; /* ASCII: "c hs traffic", in hex for EBCDIC compatibility */ static const unsigned char client_handshake_traffic[] = "\x63\x20\x68\x73\x20\x74\x72\x61\x66\x66\x69\x63"; /* ASCII: "c ap traffic", in hex for EBCDIC compatibility */ static const unsigned char client_application_traffic[] = "\x63\x20\x61\x70\x20\x74\x72\x61\x66\x66\x69\x63"; /* ASCII: "s hs traffic", in hex for EBCDIC compatibility */ static const unsigned char server_handshake_traffic[] = "\x73\x20\x68\x73\x20\x74\x72\x61\x66\x66\x69\x63"; /* ASCII: "s ap traffic", in hex for EBCDIC compatibility */ static const unsigned char server_application_traffic[] = "\x73\x20\x61\x70\x20\x74\x72\x61\x66\x66\x69\x63"; /* ASCII: "exp master", in hex for EBCDIC compatibility */ static const unsigned char exporter_master_secret[] = "\x65\x78\x70\x20\x6D\x61\x73\x74\x65\x72"; /* ASCII: "res master", in hex for EBCDIC compatibility */ static const unsigned char resumption_master_secret[] = "\x72\x65\x73\x20\x6D\x61\x73\x74\x65\x72"; /* ASCII: "e exp master", in hex for EBCDIC compatibility */ static const unsigned char early_exporter_master_secret[] = "\x65\x20\x65\x78\x70\x20\x6D\x61\x73\x74\x65\x72"; unsigned char iv[EVP_MAX_IV_LENGTH]; unsigned char key[EVP_MAX_KEY_LENGTH]; unsigned char secret[EVP_MAX_MD_SIZE]; unsigned char hashval[EVP_MAX_MD_SIZE]; unsigned char *hash = hashval; unsigned char *insecret; unsigned char *finsecret = NULL; const char *log_label = NULL; int finsecretlen = 0; const unsigned char *label; size_t labellen, hashlen = 0; int ret = 0; const EVP_MD *md = NULL; const EVP_CIPHER *cipher = NULL; SSL_CTX *sctx = SSL_CONNECTION_GET_CTX(s); size_t keylen, ivlen, taglen; int level; int direction = (which & SSL3_CC_READ) != 0 ? OSSL_RECORD_DIRECTION_READ : OSSL_RECORD_DIRECTION_WRITE; if (((which & SSL3_CC_CLIENT) && (which & SSL3_CC_WRITE)) || ((which & SSL3_CC_SERVER) && (which & SSL3_CC_READ))) { if (which & SSL3_CC_EARLY) { EVP_MD_CTX *mdctx = NULL; long handlen; void *hdata; unsigned int hashlenui; const SSL_CIPHER *sslcipher = SSL_SESSION_get0_cipher(s->session); insecret = s->early_secret; label = client_early_traffic; labellen = sizeof(client_early_traffic) - 1; log_label = CLIENT_EARLY_LABEL; handlen = BIO_get_mem_data(s->s3.handshake_buffer, &hdata); if (handlen <= 0) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_BAD_HANDSHAKE_LENGTH); goto err; } if (s->early_data_state == SSL_EARLY_DATA_CONNECTING && s->max_early_data > 0 && s->session->ext.max_early_data == 0) { /* * If we are attempting to send early data, and we've decided to * actually do it but max_early_data in s->session is 0 then we * must be using an external PSK. */ if (!ossl_assert(s->psksession != NULL && s->max_early_data == s->psksession->ext.max_early_data)) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); goto err; } sslcipher = SSL_SESSION_get0_cipher(s->psksession); } if (sslcipher == NULL) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_BAD_PSK); goto err; } /* * We need to calculate the handshake digest using the digest from * the session. We haven't yet selected our ciphersuite so we can't * use ssl_handshake_md(). */ mdctx = EVP_MD_CTX_new(); if (mdctx == NULL) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_EVP_LIB); goto err; } /* * This ups the ref count on cipher so we better make sure we free * it again */ if (!ssl_cipher_get_evp_cipher(sctx, sslcipher, &cipher)) { /* Error is already recorded */ SSLfatal_alert(s, SSL_AD_INTERNAL_ERROR); EVP_MD_CTX_free(mdctx); goto err; } md = ssl_md(sctx, sslcipher->algorithm2); if (md == NULL || !EVP_DigestInit_ex(mdctx, md, NULL) || !EVP_DigestUpdate(mdctx, hdata, handlen) || !EVP_DigestFinal_ex(mdctx, hashval, &hashlenui)) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); EVP_MD_CTX_free(mdctx); goto err; } hashlen = hashlenui; EVP_MD_CTX_free(mdctx); if (!tls13_hkdf_expand(s, md, insecret, early_exporter_master_secret, sizeof(early_exporter_master_secret) - 1, hashval, hashlen, s->early_exporter_master_secret, hashlen, 1)) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); goto err; } if (!ssl_log_secret(s, EARLY_EXPORTER_SECRET_LABEL, s->early_exporter_master_secret, hashlen)) { /* SSLfatal() already called */ goto err; } } else if (which & SSL3_CC_HANDSHAKE) { insecret = s->handshake_secret; finsecret = s->client_finished_secret; finsecretlen = EVP_MD_get_size(ssl_handshake_md(s)); if (finsecretlen <= 0) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); goto err; } label = client_handshake_traffic; labellen = sizeof(client_handshake_traffic) - 1; log_label = CLIENT_HANDSHAKE_LABEL; /* * The handshake hash used for the server read/client write handshake * traffic secret is the same as the hash for the server * write/client read handshake traffic secret. However, if we * processed early data then we delay changing the server * read/client write cipher state until later, and the handshake * hashes have moved on. Therefore we use the value saved earlier * when we did the server write/client read change cipher state. */ hash = s->handshake_traffic_hash; } else { insecret = s->master_secret; label = client_application_traffic; labellen = sizeof(client_application_traffic) - 1; log_label = CLIENT_APPLICATION_LABEL; /* * For this we only use the handshake hashes up until the server * Finished hash. We do not include the client's Finished, which is * what ssl_handshake_hash() would give us. Instead we use the * previously saved value. */ hash = s->server_finished_hash; } } else { /* Early data never applies to client-read/server-write */ if (which & SSL3_CC_HANDSHAKE) { insecret = s->handshake_secret; finsecret = s->server_finished_secret; finsecretlen = EVP_MD_get_size(ssl_handshake_md(s)); if (finsecretlen <= 0) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); goto err; } label = server_handshake_traffic; labellen = sizeof(server_handshake_traffic) - 1; log_label = SERVER_HANDSHAKE_LABEL; } else { insecret = s->master_secret; label = server_application_traffic; labellen = sizeof(server_application_traffic) - 1; log_label = SERVER_APPLICATION_LABEL; } } if (!(which & SSL3_CC_EARLY)) { md = ssl_handshake_md(s); cipher = s->s3.tmp.new_sym_enc; if (!ssl3_digest_cached_records(s, 1) || !ssl_handshake_hash(s, hashval, sizeof(hashval), &hashlen)) { /* SSLfatal() already called */; goto err; } } /* * Save the hash of handshakes up to now for use when we calculate the * client application traffic secret */ if (label == server_application_traffic) memcpy(s->server_finished_hash, hashval, hashlen); if (label == server_handshake_traffic) memcpy(s->handshake_traffic_hash, hashval, hashlen); if (label == client_application_traffic) { /* * We also create the resumption master secret, but this time use the * hash for the whole handshake including the Client Finished */ if (!tls13_hkdf_expand(s, ssl_handshake_md(s), insecret, resumption_master_secret, sizeof(resumption_master_secret) - 1, hashval, hashlen, s->resumption_master_secret, hashlen, 1)) { /* SSLfatal() already called */ goto err; } } /* check whether cipher is known */ if (!ossl_assert(cipher != NULL)) goto err; if (!derive_secret_key_and_iv(s, md, cipher, insecret, hash, label, labellen, secret, key, &keylen, iv, &ivlen, &taglen)) { /* SSLfatal() already called */ goto err; } if (label == server_application_traffic) { memcpy(s->server_app_traffic_secret, secret, hashlen); /* Now we create the exporter master secret */ if (!tls13_hkdf_expand(s, ssl_handshake_md(s), insecret, exporter_master_secret, sizeof(exporter_master_secret) - 1, hash, hashlen, s->exporter_master_secret, hashlen, 1)) { /* SSLfatal() already called */ goto err; } if (!ssl_log_secret(s, EXPORTER_SECRET_LABEL, s->exporter_master_secret, hashlen)) { /* SSLfatal() already called */ goto err; } } else if (label == client_application_traffic) memcpy(s->client_app_traffic_secret, secret, hashlen); if (!ssl_log_secret(s, log_label, secret, hashlen)) { /* SSLfatal() already called */ goto err; } if (finsecret != NULL && !tls13_derive_finishedkey(s, ssl_handshake_md(s), secret, finsecret, (size_t)finsecretlen)) { /* SSLfatal() already called */ goto err; } if ((which & SSL3_CC_WRITE) != 0) { if (!s->server && label == client_early_traffic) s->rlayer.wrlmethod->set_plain_alerts(s->rlayer.wrl, 1); else s->rlayer.wrlmethod->set_plain_alerts(s->rlayer.wrl, 0); } level = (which & SSL3_CC_EARLY) != 0 ? OSSL_RECORD_PROTECTION_LEVEL_EARLY : ((which &SSL3_CC_HANDSHAKE) != 0 ? OSSL_RECORD_PROTECTION_LEVEL_HANDSHAKE : OSSL_RECORD_PROTECTION_LEVEL_APPLICATION); if (!ssl_set_new_record_layer(s, s->version, direction, level, secret, hashlen, key, keylen, iv, ivlen, NULL, 0, cipher, taglen, NID_undef, NULL, NULL, md)) { /* SSLfatal already called */ goto err; } ret = 1; err: if ((which & SSL3_CC_EARLY) != 0) { /* We up-refed this so now we need to down ref */ ssl_evp_cipher_free(cipher); } OPENSSL_cleanse(key, sizeof(key)); OPENSSL_cleanse(secret, sizeof(secret)); return ret; } int tls13_update_key(SSL_CONNECTION *s, int sending) { /* ASCII: "traffic upd", in hex for EBCDIC compatibility */ static const unsigned char application_traffic[] = "\x74\x72\x61\x66\x66\x69\x63\x20\x75\x70\x64"; const EVP_MD *md = ssl_handshake_md(s); size_t hashlen; unsigned char key[EVP_MAX_KEY_LENGTH]; unsigned char *insecret; unsigned char secret[EVP_MAX_MD_SIZE]; char *log_label; size_t keylen, ivlen, taglen; int ret = 0, l; int direction = sending ? OSSL_RECORD_DIRECTION_WRITE : OSSL_RECORD_DIRECTION_READ; unsigned char iv[EVP_MAX_IV_LENGTH]; if ((l = EVP_MD_get_size(md)) <= 0) { SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR); return 0; } hashlen = (size_t)l; if (s->server == sending) insecret = s->server_app_traffic_secret; else insecret = s->client_app_traffic_secret; if (!derive_secret_key_and_iv(s, md, s->s3.tmp.new_sym_enc, insecret, NULL, application_traffic, sizeof(application_traffic) - 1, secret, key, &keylen, iv, &ivlen, &taglen)) { /* SSLfatal() already called */ goto err; } memcpy(insecret, secret, hashlen); if (!ssl_set_new_record_layer(s, s->version, direction, OSSL_RECORD_PROTECTION_LEVEL_APPLICATION, insecret, hashlen, key, keylen, iv, ivlen, NULL, 0, s->s3.tmp.new_sym_enc, taglen, NID_undef, NULL, NULL, md)) { /* SSLfatal already called */ goto err; } /* Call Key log on successful traffic secret update */ log_label = s->server == sending ? SERVER_APPLICATION_N_LABEL : CLIENT_APPLICATION_N_LABEL; if (!ssl_log_secret(s, log_label, secret, hashlen)) { /* SSLfatal() already called */ goto err; } ret = 1; err: OPENSSL_cleanse(key, sizeof(key)); OPENSSL_cleanse(secret, sizeof(secret)); return ret; } int tls13_alert_code(int code) { /* There are 2 additional alerts in TLSv1.3 compared to TLSv1.2 */ if (code == SSL_AD_MISSING_EXTENSION || code == SSL_AD_CERTIFICATE_REQUIRED) return code; return tls1_alert_code(code); } int tls13_export_keying_material(SSL_CONNECTION *s, unsigned char *out, size_t olen, const char *label, size_t llen, const unsigned char *context, size_t contextlen, int use_context) { unsigned char exportsecret[EVP_MAX_MD_SIZE]; /* ASCII: "exporter", in hex for EBCDIC compatibility */ static const unsigned char exporterlabel[] = "\x65\x78\x70\x6F\x72\x74\x65\x72"; unsigned char hash[EVP_MAX_MD_SIZE], data[EVP_MAX_MD_SIZE]; const EVP_MD *md = ssl_handshake_md(s); EVP_MD_CTX *ctx = EVP_MD_CTX_new(); unsigned int hashsize, datalen; int ret = 0; if (ctx == NULL || md == NULL || !ossl_statem_export_allowed(s)) goto err; if (!use_context) contextlen = 0; if (EVP_DigestInit_ex(ctx, md, NULL) <= 0 || EVP_DigestUpdate(ctx, context, contextlen) <= 0 || EVP_DigestFinal_ex(ctx, hash, &hashsize) <= 0 || EVP_DigestInit_ex(ctx, md, NULL) <= 0 || EVP_DigestFinal_ex(ctx, data, &datalen) <= 0 || !tls13_hkdf_expand(s, md, s->exporter_master_secret, (const unsigned char *)label, llen, data, datalen, exportsecret, hashsize, 0) || !tls13_hkdf_expand(s, md, exportsecret, exporterlabel, sizeof(exporterlabel) - 1, hash, hashsize, out, olen, 0)) goto err; ret = 1; err: EVP_MD_CTX_free(ctx); return ret; } int tls13_export_keying_material_early(SSL_CONNECTION *s, unsigned char *out, size_t olen, const char *label, size_t llen, const unsigned char *context, size_t contextlen) { /* ASCII: "exporter", in hex for EBCDIC compatibility */ static const unsigned char exporterlabel[] = "\x65\x78\x70\x6F\x72\x74\x65\x72"; unsigned char exportsecret[EVP_MAX_MD_SIZE]; unsigned char hash[EVP_MAX_MD_SIZE], data[EVP_MAX_MD_SIZE]; const EVP_MD *md; EVP_MD_CTX *ctx = EVP_MD_CTX_new(); unsigned int hashsize, datalen; int ret = 0; const SSL_CIPHER *sslcipher; if (ctx == NULL || !ossl_statem_export_early_allowed(s)) goto err; if (!s->server && s->max_early_data > 0 && s->session->ext.max_early_data == 0) sslcipher = SSL_SESSION_get0_cipher(s->psksession); else sslcipher = SSL_SESSION_get0_cipher(s->session); md = ssl_md(SSL_CONNECTION_GET_CTX(s), sslcipher->algorithm2); /* * Calculate the hash value and store it in |data|. The reason why * the empty string is used is that the definition of TLS-Exporter * is like so: * * TLS-Exporter(label, context_value, key_length) = * HKDF-Expand-Label(Derive-Secret(Secret, label, ""), * "exporter", Hash(context_value), key_length) * * Derive-Secret(Secret, Label, Messages) = * HKDF-Expand-Label(Secret, Label, * Transcript-Hash(Messages), Hash.length) * * Here Transcript-Hash is the cipher suite hash algorithm. */ if (md == NULL || EVP_DigestInit_ex(ctx, md, NULL) <= 0 || EVP_DigestUpdate(ctx, context, contextlen) <= 0 || EVP_DigestFinal_ex(ctx, hash, &hashsize) <= 0 || EVP_DigestInit_ex(ctx, md, NULL) <= 0 || EVP_DigestFinal_ex(ctx, data, &datalen) <= 0 || !tls13_hkdf_expand(s, md, s->early_exporter_master_secret, (const unsigned char *)label, llen, data, datalen, exportsecret, hashsize, 0) || !tls13_hkdf_expand(s, md, exportsecret, exporterlabel, sizeof(exporterlabel) - 1, hash, hashsize, out, olen, 0)) goto err; ret = 1; err: EVP_MD_CTX_free(ctx); return ret; }