X-Git-Url: https://git.openssl.org/gitweb/?p=openssl.git;a=blobdiff_plain;f=ssl%2Ftls13_enc.c;h=1f956e61e9c1c8a3b9be2137444b9338d6966848;hp=7f4395843a82fad7a47a091f899e7f672bd27d63;hb=72a7a7021fa8bc82a11bc08bac1b0241a92143d0;hpb=d4ef4fbf46a51837a54e4a7cd0140eb9f08fdf30;ds=sidebyside diff --git a/ssl/tls13_enc.c b/ssl/tls13_enc.c index 7f4395843a..1f956e61e9 100644 --- a/ssl/tls13_enc.c +++ b/ssl/tls13_enc.c @@ -1,5 +1,5 @@ /* - * Copyright 2016-2018 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 @@ -13,7 +13,7 @@ #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]; @@ -22,30 +22,47 @@ static const unsigned char default_zeros[EVP_MAX_MD_SIZE]; * 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. Returns 1 on success 0 on failure. + * 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 *data, size_t datalen, - unsigned char *out, size_t outlen) + unsigned char *out, size_t outlen, int fatal) { - const unsigned char label_prefix[] = "tls13 "; + 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) @@ -59,8 +76,11 @@ int tls13_hkdf_expand(SSL *s, const EVP_MD *md, const unsigned char *secret, || !WPACKET_finish(&pkt)) { EVP_PKEY_CTX_free(pctx); WPACKET_cleanup(&pkt); - SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS13_HKDF_EXPAND, - ERR_R_INTERNAL_ERROR); + 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; } @@ -74,9 +94,13 @@ int tls13_hkdf_expand(SSL *s, const EVP_MD *md, const unsigned char *secret, EVP_PKEY_CTX_free(pctx); - if (ret != 0) - SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS13_HKDF_EXPAND, - ERR_R_INTERNAL_ERROR); + 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; } @@ -91,7 +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, 0, key, keylen); + NULL, 0, key, keylen, 1); } /* @@ -104,7 +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, 0, iv, ivlen); + NULL, 0, iv, ivlen, 1); } int tls13_derive_finishedkey(SSL *s, const EVP_MD *md, @@ -114,7 +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, 0, fin, finlen); + sizeof(finishedlabel) - 1, NULL, 0, fin, finlen, 1); } /* @@ -129,6 +153,7 @@ 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"; @@ -140,7 +165,14 @@ int tls13_generate_secret(SSL *s, const EVP_MD *md, 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; @@ -169,7 +201,7 @@ int tls13_generate_secret(SSL *s, const EVP_MD *md, if (!tls13_hkdf_expand(s, md, prevsecret, (unsigned char *)derived_secret_label, sizeof(derived_secret_label) - 1, hash, mdlen, - preextractsec, mdlen)) { + preextractsec, mdlen, 1)) { /* SSLfatal() already called */ EVP_PKEY_CTX_free(pctx); return 0; @@ -247,12 +279,24 @@ size_t tls13_final_finish_mac(SSL *s, const char *str, size_t slen, goto err; } - if (str == s->method->ssl3_enc->server_finished_label) + 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 + } 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 @@ -279,11 +323,9 @@ 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)) { + 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; @@ -305,10 +347,19 @@ static int derive_secret_key_and_iv(SSL *s, int sending, 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, hashlen, - secret, hashlen)) { + secret, hashlen, 1)) { /* SSLfatal() already called */ goto err; } @@ -397,7 +448,7 @@ int tls13_change_cipher_state(SSL *s, int which) RECORD_LAYER_reset_read_sequence(&s->rlayer); } else { - s->statem.invalid_enc_write_ctx = 1; + s->statem.enc_write_state = ENC_WRITE_STATE_INVALID; if (s->enc_write_ctx != NULL) { EVP_CIPHER_CTX_reset(s->enc_write_ctx); } else { @@ -407,7 +458,6 @@ int tls13_change_cipher_state(SSL *s, int which) SSL_F_TLS13_CHANGE_CIPHER_STATE, ERR_R_MALLOC_FAILURE); goto err; } - EVP_CIPHER_CTX_ctrl(s->enc_write_ctx, EVP_CTRL_SET_DRBG, 0, s->drbg); } ciph_ctx = s->enc_write_ctx; iv = s->write_iv; @@ -489,11 +539,18 @@ int tls13_change_cipher_state(SSL *s, int which) early_exporter_master_secret, sizeof(early_exporter_master_secret) - 1, hashval, hashlen, - s->early_exporter_master_secret, 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; @@ -569,12 +626,11 @@ 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, hashlen, s->session->master_key, - hashlen)) { + 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, @@ -591,7 +647,13 @@ int tls13_change_cipher_state(SSL *s, int which) exporter_master_secret, sizeof(exporter_master_secret) - 1, hash, hashlen, s->exporter_master_secret, - hashlen)) { + 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; } @@ -610,7 +672,10 @@ int tls13_change_cipher_state(SSL *s, int which) goto err; } - s->statem.invalid_enc_write_ctx = 0; + 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)); @@ -633,7 +698,7 @@ int tls13_update_key(SSL *s, int sending) insecret = s->client_app_traffic_secret; if (sending) { - s->statem.invalid_enc_write_ctx = 1; + 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); @@ -654,7 +719,7 @@ int tls13_update_key(SSL *s, int sending) memcpy(insecret, secret, hashlen); - s->statem.invalid_enc_write_ctx = 0; + s->statem.enc_write_state = ENC_WRITE_STATE_VALID; ret = 1; err: OPENSSL_cleanse(secret, sizeof(secret)); @@ -663,7 +728,8 @@ int tls13_update_key(SSL *s, int sending) int tls13_alert_code(int code) { - if (code == SSL_AD_MISSING_EXTENSION) + /* 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); @@ -695,10 +761,10 @@ int tls13_export_keying_material(SSL *s, unsigned char *out, size_t olen, || 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) + data, datalen, exportsecret, hashsize, 0) || !tls13_hkdf_expand(s, md, exportsecret, exporterlabel, sizeof(exporterlabel) - 1, hash, hashsize, - out, olen)) + out, olen, 0)) goto err; ret = 1; @@ -754,10 +820,10 @@ int tls13_export_keying_material_early(SSL *s, unsigned char *out, size_t olen, || 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) + data, datalen, exportsecret, hashsize, 0) || !tls13_hkdf_expand(s, md, exportsecret, exporterlabel, sizeof(exporterlabel) - 1, hash, hashsize, - out, olen)) + out, olen, 0)) goto err; ret = 1;