X-Git-Url: https://git.openssl.org/gitweb/?p=openssl.git;a=blobdiff_plain;f=ssl%2Ftls13_enc.c;h=1f956e61e9c1c8a3b9be2137444b9338d6966848;hp=d42be60c6710213d1571d0febe941171226b4187;hb=72a7a7021fa8bc82a11bc08bac1b0241a92143d0;hpb=fe5e20fd267bae655c37ba8d67d74c0db566e088 diff --git a/ssl/tls13_enc.c b/ssl/tls13_enc.c index d42be60c67..1f956e61e9 100644 --- a/ssl/tls13_enc.c +++ b/ssl/tls13_enc.c @@ -1,5 +1,5 @@ /* - * Copyright 2016 The OpenSSL Project Authors. All Rights Reserved. + * Copyright 2016-2019 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 @@ -9,42 +9,60 @@ #include #include "ssl_locl.h" +#include "internal/cryptlib.h" #include #include -#define TLS13_MAX_LABEL_LEN 246 +#define TLS13_MAX_LABEL_LEN 249 /* Always filled with zeros */ static const unsigned char default_zeros[EVP_MAX_MD_SIZE]; /* - * Given a |secret|; a |label| of length |labellen|; and a |hash| of the - * handshake messages, derive a new secret |outlen| bytes long and store it in - * the location pointed to be |out|. The |hash| value may be NULL. Returns 1 on - * success 0 on failure. + * 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. */ int tls13_hkdf_expand(SSL *s, const EVP_MD *md, const unsigned char *secret, const unsigned char *label, size_t labellen, - const unsigned char *hash, - unsigned char *out, size_t outlen) + const unsigned char *data, size_t datalen, + unsigned char *out, size_t outlen, int fatal) { - const unsigned char label_prefix[] = "TLS 1.3, "; + static const unsigned char label_prefix[] = "tls13 "; EVP_PKEY_CTX *pctx = EVP_PKEY_CTX_new_id(EVP_PKEY_HKDF, NULL); int ret; size_t hkdflabellen; size_t hashlen; /* - * 2 bytes for length of whole HkdfLabel + 1 byte for length of combined - * prefix and label + bytes for the label itself + bytes for the hash + * 2 bytes for length of derived secret + 1 byte for length of combined + * prefix and label + bytes for the label itself + 1 byte length of hash + * + bytes for the hash itself */ unsigned char hkdflabel[sizeof(uint16_t) + sizeof(uint8_t) + - + sizeof(label_prefix) + TLS13_MAX_LABEL_LEN - + EVP_MAX_MD_SIZE]; + + (sizeof(label_prefix) - 1) + TLS13_MAX_LABEL_LEN + + 1 + EVP_MAX_MD_SIZE]; WPACKET pkt; if (pctx == NULL) return 0; + if (labellen > TLS13_MAX_LABEL_LEN) { + if (fatal) { + SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS13_HKDF_EXPAND, + ERR_R_INTERNAL_ERROR); + } else { + /* + * Probably we have been called from SSL_export_keying_material(), + * or SSL_export_keying_material_early(). + */ + SSLerr(SSL_F_TLS13_HKDF_EXPAND, SSL_R_TLS_ILLEGAL_EXPORTER_LABEL); + } + EVP_PKEY_CTX_free(pctx); + return 0; + } + hashlen = EVP_MD_size(md); if (!WPACKET_init_static_len(&pkt, hkdflabel, sizeof(hkdflabel), 0) @@ -53,11 +71,16 @@ int tls13_hkdf_expand(SSL *s, const EVP_MD *md, const unsigned char *secret, || !WPACKET_memcpy(&pkt, label_prefix, sizeof(label_prefix) - 1) || !WPACKET_memcpy(&pkt, label, labellen) || !WPACKET_close(&pkt) - || !WPACKET_sub_memcpy_u8(&pkt, hash, (hash == NULL) ? 0 : hashlen) + || !WPACKET_sub_memcpy_u8(&pkt, data, (data == NULL) ? 0 : datalen) || !WPACKET_get_total_written(&pkt, &hkdflabellen) || !WPACKET_finish(&pkt)) { EVP_PKEY_CTX_free(pctx); WPACKET_cleanup(&pkt); + if (fatal) + SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS13_HKDF_EXPAND, + ERR_R_INTERNAL_ERROR); + else + SSLerr(SSL_F_TLS13_HKDF_EXPAND, ERR_R_INTERNAL_ERROR); return 0; } @@ -71,6 +94,14 @@ int tls13_hkdf_expand(SSL *s, const EVP_MD *md, const unsigned char *secret, EVP_PKEY_CTX_free(pctx); + if (ret != 0) { + if (fatal) + SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS13_HKDF_EXPAND, + ERR_R_INTERNAL_ERROR); + else + SSLerr(SSL_F_TLS13_HKDF_EXPAND, ERR_R_INTERNAL_ERROR); + } + return ret == 0; } @@ -84,7 +115,7 @@ int tls13_derive_key(SSL *s, const EVP_MD *md, const unsigned char *secret, static const unsigned char keylabel[] = "key"; return tls13_hkdf_expand(s, md, secret, keylabel, sizeof(keylabel) - 1, - NULL, key, keylen); + NULL, 0, key, keylen, 1); } /* @@ -97,7 +128,7 @@ int tls13_derive_iv(SSL *s, const EVP_MD *md, const unsigned char *secret, static const unsigned char ivlabel[] = "iv"; return tls13_hkdf_expand(s, md, secret, ivlabel, sizeof(ivlabel) - 1, - NULL, iv, ivlen); + NULL, 0, iv, ivlen, 1); } int tls13_derive_finishedkey(SSL *s, const EVP_MD *md, @@ -107,7 +138,7 @@ int tls13_derive_finishedkey(SSL *s, const EVP_MD *md, static const unsigned char finishedlabel[] = "finished"; return tls13_hkdf_expand(s, md, secret, finishedlabel, - sizeof(finishedlabel) - 1, NULL, fin, finlen); + sizeof(finishedlabel) - 1, NULL, 0, fin, finlen, 1); } /* @@ -122,13 +153,26 @@ int tls13_generate_secret(SSL *s, const EVP_MD *md, unsigned char *outsecret) { size_t mdlen, prevsecretlen; + int mdleni; int ret; EVP_PKEY_CTX *pctx = EVP_PKEY_CTX_new_id(EVP_PKEY_HKDF, NULL); + static const char derived_secret_label[] = "derived"; + unsigned char preextractsec[EVP_MAX_MD_SIZE]; - if (pctx == NULL) + if (pctx == NULL) { + SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS13_GENERATE_SECRET, + ERR_R_INTERNAL_ERROR); return 0; + } - mdlen = EVP_MD_size(md); + mdleni = EVP_MD_size(md); + /* Ensure cast to size_t is safe */ + if (!ossl_assert(mdleni >= 0)) { + SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS13_GENERATE_SECRET, + ERR_R_INTERNAL_ERROR); + return 0; + } + mdlen = (size_t)mdleni; if (insecret == NULL) { insecret = default_zeros; @@ -138,6 +182,32 @@ int tls13_generate_secret(SSL *s, const EVP_MD *md, prevsecret = default_zeros; prevsecretlen = 0; } else { + EVP_MD_CTX *mctx = EVP_MD_CTX_new(); + unsigned char hash[EVP_MAX_MD_SIZE]; + + /* The pre-extract derive step uses a hash of no messages */ + if (mctx == NULL + || EVP_DigestInit_ex(mctx, md, NULL) <= 0 + || EVP_DigestFinal_ex(mctx, hash, NULL) <= 0) { + SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS13_GENERATE_SECRET, + ERR_R_INTERNAL_ERROR); + EVP_MD_CTX_free(mctx); + EVP_PKEY_CTX_free(pctx); + return 0; + } + EVP_MD_CTX_free(mctx); + + /* Generate the pre-extract secret */ + if (!tls13_hkdf_expand(s, md, prevsecret, + (unsigned char *)derived_secret_label, + sizeof(derived_secret_label) - 1, hash, mdlen, + preextractsec, mdlen, 1)) { + /* SSLfatal() already called */ + EVP_PKEY_CTX_free(pctx); + return 0; + } + + prevsecret = preextractsec; prevsecretlen = mdlen; } @@ -151,7 +221,13 @@ int tls13_generate_secret(SSL *s, const EVP_MD *md, || EVP_PKEY_derive(pctx, outsecret, &mdlen) <= 0; + if (ret != 0) + SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS13_GENERATE_SECRET, + ERR_R_INTERNAL_ERROR); + EVP_PKEY_CTX_free(pctx); + if (prevsecret == preextractsec) + OPENSSL_cleanse(preextractsec, mdlen); return ret == 0; } @@ -163,6 +239,7 @@ int tls13_generate_secret(SSL *s, const EVP_MD *md, int tls13_generate_handshake_secret(SSL *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); @@ -180,6 +257,7 @@ int tls13_generate_master_secret(SSL *s, unsigned char *out, const EVP_MD *md = ssl_handshake_md(s); *secret_size = EVP_MD_size(md); + /* Calls SSLfatal() if required */ return tls13_generate_secret(s, md, prev, NULL, 0, out); } @@ -196,22 +274,39 @@ size_t tls13_final_finish_mac(SSL *s, const char *str, size_t slen, EVP_PKEY *key = NULL; EVP_MD_CTX *ctx = EVP_MD_CTX_new(); - if (!ssl_handshake_hash(s, hash, sizeof(hash), &hashlen)) + if (!ssl_handshake_hash(s, hash, sizeof(hash), &hashlen)) { + /* SSLfatal() already called */ goto err; + } - if (str == s->method->ssl3_enc->server_finished_label) - key = EVP_PKEY_new_mac_key(EVP_PKEY_HMAC, NULL, - s->server_finished_secret, hashlen); - else - key = EVP_PKEY_new_mac_key(EVP_PKEY_HMAC, NULL, - s->client_finished_secret, hashlen); + if (str == s->method->ssl3_enc->server_finished_label) { + key = EVP_PKEY_new_raw_private_key(EVP_PKEY_HMAC, NULL, + s->server_finished_secret, hashlen); + } else if (SSL_IS_FIRST_HANDSHAKE(s)) { + key = EVP_PKEY_new_raw_private_key(EVP_PKEY_HMAC, NULL, + s->client_finished_secret, hashlen); + } else { + unsigned char finsecret[EVP_MAX_MD_SIZE]; + + if (!tls13_derive_finishedkey(s, ssl_handshake_md(s), + s->client_app_traffic_secret, + finsecret, hashlen)) + goto err; + + key = EVP_PKEY_new_raw_private_key(EVP_PKEY_HMAC, NULL, finsecret, + hashlen); + OPENSSL_cleanse(finsecret, sizeof(finsecret)); + } if (key == NULL || ctx == NULL || EVP_DigestSignInit(ctx, NULL, md, NULL, key) <= 0 || EVP_DigestSignUpdate(ctx, hash, hashlen) <= 0 - || EVP_DigestSignFinal(ctx, out, &hashlen) <= 0) + || EVP_DigestSignFinal(ctx, out, &hashlen) <= 0) { + SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS13_FINAL_FINISH_MAC, + ERR_R_INTERNAL_ERROR); goto err; + } ret = hashlen; err: @@ -228,12 +323,11 @@ int tls13_setup_key_block(SSL *s) { const EVP_CIPHER *c; const EVP_MD *hash; - int mac_type = NID_undef; s->session->cipher = s->s3->tmp.new_cipher; - if (!ssl_cipher_get_evp - (s->session, &c, &hash, &mac_type, NULL, NULL, 0)) { - SSLerr(SSL_F_TLS13_SETUP_KEY_BLOCK, SSL_R_CIPHER_OR_HASH_UNAVAILABLE); + if (!ssl_cipher_get_evp(s->session, &c, &hash, NULL, NULL, NULL, 0)) { + SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS13_SETUP_KEY_BLOCK, + SSL_R_CIPHER_OR_HASH_UNAVAILABLE); return 0; } @@ -243,7 +337,7 @@ int tls13_setup_key_block(SSL *s) return 1; } -static int derive_secret_key_and_iv(SSL *s, int send, const EVP_MD *md, +static int derive_secret_key_and_iv(SSL *s, int sending, const EVP_MD *md, const EVP_CIPHER *ciph, const unsigned char *insecret, const unsigned char *hash, @@ -253,20 +347,36 @@ static int derive_secret_key_and_iv(SSL *s, int send, const EVP_MD *md, { unsigned char key[EVP_MAX_KEY_LENGTH]; size_t ivlen, keylen, taglen; - size_t hashlen = EVP_MD_size(md); + int hashleni = EVP_MD_size(md); + size_t hashlen; + + /* Ensure cast to size_t is safe */ + if (!ossl_assert(hashleni >= 0)) { + SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_DERIVE_SECRET_KEY_AND_IV, + ERR_R_EVP_LIB); + goto err; + } + hashlen = (size_t)hashleni; - if (!tls13_hkdf_expand(s, md, insecret, label, labellen, hash, secret, - hashlen)) { - SSLerr(SSL_F_DERIVE_SECRET_KEY_AND_IV, ERR_R_INTERNAL_ERROR); + if (!tls13_hkdf_expand(s, md, insecret, label, labellen, hash, hashlen, + secret, hashlen, 1)) { + /* SSLfatal() already called */ goto err; } /* TODO(size_t): convert me */ keylen = EVP_CIPHER_key_length(ciph); if (EVP_CIPHER_mode(ciph) == EVP_CIPH_CCM_MODE) { + uint32_t algenc; + ivlen = EVP_CCM_TLS_IV_LEN; - if (s->s3->tmp.new_cipher->algorithm_enc - & (SSL_AES128CCM8 | SSL_AES256CCM8)) + if (s->s3->tmp.new_cipher == NULL) { + /* We've not selected a cipher yet - we must be doing early data */ + algenc = s->session->cipher->algorithm_enc; + } else { + algenc = s->s3->tmp.new_cipher->algorithm_enc; + } + if (algenc & (SSL_AES128CCM8 | SSL_AES256CCM8)) taglen = EVP_CCM8_TLS_TAG_LEN; else taglen = EVP_CCM_TLS_TAG_LEN; @@ -277,33 +387,20 @@ static int derive_secret_key_and_iv(SSL *s, int send, const EVP_MD *md, if (!tls13_derive_key(s, md, secret, key, keylen) || !tls13_derive_iv(s, md, secret, iv, ivlen)) { - SSLerr(SSL_F_DERIVE_SECRET_KEY_AND_IV, ERR_R_INTERNAL_ERROR); + /* SSLfatal() already called */ goto err; } - if (EVP_CipherInit_ex(ciph_ctx, ciph, NULL, NULL, NULL, send) <= 0 + if (EVP_CipherInit_ex(ciph_ctx, ciph, NULL, NULL, NULL, sending) <= 0 || !EVP_CIPHER_CTX_ctrl(ciph_ctx, EVP_CTRL_AEAD_SET_IVLEN, ivlen, NULL) || (taglen != 0 && !EVP_CIPHER_CTX_ctrl(ciph_ctx, EVP_CTRL_AEAD_SET_TAG, taglen, NULL)) || EVP_CipherInit_ex(ciph_ctx, NULL, NULL, key, NULL, -1) <= 0) { - SSLerr(SSL_F_DERIVE_SECRET_KEY_AND_IV, ERR_R_EVP_LIB); + SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_DERIVE_SECRET_KEY_AND_IV, + ERR_R_EVP_LIB); goto err; } -#ifdef OPENSSL_SSL_TRACE_CRYPTO - if (s->msg_callback) { - int wh = send ? TLS1_RT_CRYPTO_WRITE : 0; - - if (ciph->key_len) - s->msg_callback(2, s->version, wh | TLS1_RT_CRYPTO_KEY, - key, ciph->key_len, s, s->msg_callback_arg); - - wh |= TLS1_RT_CRYPTO_IV; - s->msg_callback(2, s->version, wh, iv, ivlen, s, - s->msg_callback_arg); - } -#endif - return 1; err: OPENSSL_cleanse(key, sizeof(key)); @@ -312,18 +409,14 @@ static int derive_secret_key_and_iv(SSL *s, int send, const EVP_MD *md, int tls13_change_cipher_state(SSL *s, int which) { - static const unsigned char client_early_traffic[] = - "client early traffic secret"; - static const unsigned char client_handshake_traffic[] = - "client handshake traffic secret"; - static const unsigned char client_application_traffic[] = - "client application traffic secret"; - static const unsigned char server_handshake_traffic[] = - "server handshake traffic secret"; - static const unsigned char server_application_traffic[] = - "server application traffic secret"; - static const unsigned char resumption_master_secret[] = - "resumption master secret"; + static const unsigned char client_early_traffic[] = "c e traffic"; + static const unsigned char client_handshake_traffic[] = "c hs traffic"; + static const unsigned char client_application_traffic[] = "c ap traffic"; + static const unsigned char server_handshake_traffic[] = "s hs traffic"; + static const unsigned char server_application_traffic[] = "s ap traffic"; + static const unsigned char exporter_master_secret[] = "exp master"; + static const unsigned char resumption_master_secret[] = "res master"; + static const unsigned char early_exporter_master_secret[] = "e exp master"; unsigned char *iv; unsigned char secret[EVP_MAX_MD_SIZE]; unsigned char hashval[EVP_MAX_MD_SIZE]; @@ -336,8 +429,8 @@ int tls13_change_cipher_state(SSL *s, int which) const unsigned char *label; size_t labellen, hashlen = 0; int ret = 0; - const EVP_MD *md; - const EVP_CIPHER *cipher; + const EVP_MD *md = NULL; + const EVP_CIPHER *cipher = NULL; if (which & SSL3_CC_READ) { if (s->enc_read_ctx != NULL) { @@ -345,7 +438,8 @@ int tls13_change_cipher_state(SSL *s, int which) } else { s->enc_read_ctx = EVP_CIPHER_CTX_new(); if (s->enc_read_ctx == NULL) { - SSLerr(SSL_F_TLS13_CHANGE_CIPHER_STATE, ERR_R_MALLOC_FAILURE); + SSLfatal(s, SSL_AD_INTERNAL_ERROR, + SSL_F_TLS13_CHANGE_CIPHER_STATE, ERR_R_MALLOC_FAILURE); goto err; } } @@ -354,12 +448,14 @@ int tls13_change_cipher_state(SSL *s, int which) RECORD_LAYER_reset_read_sequence(&s->rlayer); } else { + s->statem.enc_write_state = ENC_WRITE_STATE_INVALID; if (s->enc_write_ctx != NULL) { EVP_CIPHER_CTX_reset(s->enc_write_ctx); } else { s->enc_write_ctx = EVP_CIPHER_CTX_new(); if (s->enc_write_ctx == NULL) { - SSLerr(SSL_F_TLS13_CHANGE_CIPHER_STATE, ERR_R_MALLOC_FAILURE); + SSLfatal(s, SSL_AD_INTERNAL_ERROR, + SSL_F_TLS13_CHANGE_CIPHER_STATE, ERR_R_MALLOC_FAILURE); goto err; } } @@ -385,12 +481,33 @@ int tls13_change_cipher_state(SSL *s, int which) handlen = BIO_get_mem_data(s->s3->handshake_buffer, &hdata); if (handlen <= 0) { - SSLerr(SSL_F_TLS13_CHANGE_CIPHER_STATE, - SSL_R_BAD_HANDSHAKE_LENGTH); + SSLfatal(s, SSL_AD_INTERNAL_ERROR, + SSL_F_TLS13_CHANGE_CIPHER_STATE, + 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, + SSL_F_TLS13_CHANGE_CIPHER_STATE, + ERR_R_INTERNAL_ERROR); + goto err; + } + sslcipher = SSL_SESSION_get0_cipher(s->psksession); + } if (sslcipher == NULL) { - SSLerr(SSL_F_TLS13_CHANGE_CIPHER_STATE, ERR_R_INTERNAL_ERROR); + SSLfatal(s, SSL_AD_INTERNAL_ERROR, + SSL_F_TLS13_CHANGE_CIPHER_STATE, SSL_R_BAD_PSK); goto err; } @@ -401,7 +518,8 @@ int tls13_change_cipher_state(SSL *s, int which) */ mdctx = EVP_MD_CTX_new(); if (mdctx == NULL) { - SSLerr(SSL_F_TLS13_CHANGE_CIPHER_STATE, ERR_R_MALLOC_FAILURE); + SSLfatal(s, SSL_AD_INTERNAL_ERROR, + SSL_F_TLS13_CHANGE_CIPHER_STATE, ERR_R_MALLOC_FAILURE); goto err; } cipher = EVP_get_cipherbynid(SSL_CIPHER_get_cipher_nid(sslcipher)); @@ -409,12 +527,30 @@ int tls13_change_cipher_state(SSL *s, int which) if (md == NULL || !EVP_DigestInit_ex(mdctx, md, NULL) || !EVP_DigestUpdate(mdctx, hdata, handlen) || !EVP_DigestFinal_ex(mdctx, hashval, &hashlenui)) { - SSLerr(SSL_F_TLS13_CHANGE_CIPHER_STATE, ERR_R_INTERNAL_ERROR); + SSLfatal(s, SSL_AD_INTERNAL_ERROR, + SSL_F_TLS13_CHANGE_CIPHER_STATE, 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, + SSL_F_TLS13_CHANGE_CIPHER_STATE, 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; @@ -423,15 +559,15 @@ int tls13_change_cipher_state(SSL *s, int which) labellen = sizeof(client_handshake_traffic) - 1; log_label = CLIENT_HANDSHAKE_LABEL; /* - * The hanshake hash used for the server read handshake traffic - * secret is the same as the hash for the server write handshake - * traffic secret. However, if we processed early data then we delay - * changing the server read cipher state until later, and the - * handshake hashes have moved on. Therefore we use the value saved - * earlier when we did the server write change cipher state. + * 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. */ - if (s->server) - hash = s->handshake_traffic_hash; + hash = s->handshake_traffic_hash; } else { insecret = s->master_secret; label = client_application_traffic; @@ -467,7 +603,7 @@ int tls13_change_cipher_state(SSL *s, int which) cipher = s->s3->tmp.new_sym_enc; if (!ssl3_digest_cached_records(s, 1) || !ssl_handshake_hash(s, hashval, sizeof(hashval), &hashlen)) { - SSLerr(SSL_F_TLS13_CHANGE_CIPHER_STATE, ERR_R_INTERNAL_ERROR); + /* SSLfatal() already called */; goto err; } } @@ -479,7 +615,7 @@ int tls13_change_cipher_state(SSL *s, int which) if (label == server_application_traffic) memcpy(s->server_finished_hash, hashval, hashlen); - if (s->server && label == server_handshake_traffic) + if (label == server_handshake_traffic) memcpy(s->handshake_traffic_hash, hashval, hashlen); if (label == client_application_traffic) { @@ -490,46 +626,65 @@ int tls13_change_cipher_state(SSL *s, int which) if (!tls13_hkdf_expand(s, ssl_handshake_md(s), insecret, resumption_master_secret, sizeof(resumption_master_secret) - 1, - hashval, s->session->master_key, hashlen)) { - SSLerr(SSL_F_TLS13_CHANGE_CIPHER_STATE, ERR_R_INTERNAL_ERROR); + hashval, hashlen, s->resumption_master_secret, + hashlen, 1)) { + /* SSLfatal() already called */ goto err; } - s->session->master_key_length = hashlen; } if (!derive_secret_key_and_iv(s, which & SSL3_CC_WRITE, md, cipher, insecret, hash, label, labellen, secret, iv, ciph_ctx)) { + /* SSLfatal() already called */ goto err; } - if (label == server_application_traffic) + if (label == server_application_traffic) { memcpy(s->server_app_traffic_secret, secret, hashlen); - else if (label == client_application_traffic) + /* 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)) { - SSLerr(SSL_F_TLS13_CHANGE_CIPHER_STATE, ERR_R_INTERNAL_ERROR); + /* SSLfatal() already called */ goto err; } if (finsecret != NULL && !tls13_derive_finishedkey(s, ssl_handshake_md(s), secret, finsecret, finsecretlen)) { - SSLerr(SSL_F_TLS13_CHANGE_CIPHER_STATE, ERR_R_INTERNAL_ERROR); + /* SSLfatal() already called */ goto err; } + if (!s->server && label == client_early_traffic) + s->statem.enc_write_state = ENC_WRITE_STATE_WRITE_PLAIN_ALERTS; + else + s->statem.enc_write_state = ENC_WRITE_STATE_VALID; ret = 1; err: OPENSSL_cleanse(secret, sizeof(secret)); return ret; } -int tls13_update_key(SSL *s, int send) +int tls13_update_key(SSL *s, int sending) { - static const unsigned char application_traffic[] = - "application traffic secret"; + static const unsigned char application_traffic[] = "traffic upd"; const EVP_MD *md = ssl_handshake_md(s); size_t hashlen = EVP_MD_size(md); unsigned char *insecret, *iv; @@ -537,12 +692,13 @@ int tls13_update_key(SSL *s, int send) EVP_CIPHER_CTX *ciph_ctx; int ret = 0; - if (s->server == send) + if (s->server == sending) insecret = s->server_app_traffic_secret; else insecret = s->client_app_traffic_secret; - if (send) { + if (sending) { + s->statem.enc_write_state = ENC_WRITE_STATE_INVALID; iv = s->write_iv; ciph_ctx = s->enc_write_ctx; RECORD_LAYER_reset_write_sequence(&s->rlayer); @@ -552,15 +708,18 @@ int tls13_update_key(SSL *s, int send) RECORD_LAYER_reset_read_sequence(&s->rlayer); } - if (!derive_secret_key_and_iv(s, send, ssl_handshake_md(s), + if (!derive_secret_key_and_iv(s, sending, ssl_handshake_md(s), s->s3->tmp.new_sym_enc, insecret, NULL, application_traffic, sizeof(application_traffic) - 1, secret, iv, - ciph_ctx)) + ciph_ctx)) { + /* SSLfatal() already called */ goto err; + } memcpy(insecret, secret, hashlen); + s->statem.enc_write_state = ENC_WRITE_STATE_VALID; ret = 1; err: OPENSSL_cleanse(secret, sizeof(secret)); @@ -569,8 +728,106 @@ int tls13_update_key(SSL *s, int send) int tls13_alert_code(int code) { - if (code == SSL_AD_MISSING_EXTENSION || code == SSL_AD_END_OF_EARLY_DATA) + /* 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 *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]; + static const unsigned char exporterlabel[] = "exporter"; + 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 || !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 *s, unsigned char *out, size_t olen, + const char *label, size_t llen, + const unsigned char *context, + size_t contextlen) +{ + static const unsigned char exporterlabel[] = "exporter"; + 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(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 (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; +}