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- /*
- * Copyright 2016-2020 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 <stdlib.h>
- #include "ssl_local.h"
- #include "internal/cryptlib.h"
- #include <openssl/evp.h>
- #include <openssl/kdf.h>
- #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 |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 *data, size_t datalen,
- unsigned char *out, size_t outlen, int fatal)
- {
- #ifdef CHARSET_EBCDIC
- static const unsigned char label_prefix[] = { 0x74, 0x6C, 0x73, 0x31, 0x33, 0x20, 0x00 };
- #else
- static const unsigned char label_prefix[] = "tls13 ";
- #endif
- 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 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) - 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)
- || !WPACKET_put_bytes_u16(&pkt, outlen)
- || !WPACKET_start_sub_packet_u8(&pkt)
- || !WPACKET_memcpy(&pkt, label_prefix, sizeof(label_prefix) - 1)
- || !WPACKET_memcpy(&pkt, label, labellen)
- || !WPACKET_close(&pkt)
- || !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;
- }
- ret = EVP_PKEY_derive_init(pctx) <= 0
- || EVP_PKEY_CTX_hkdf_mode(pctx, EVP_PKEY_HKDEF_MODE_EXPAND_ONLY)
- <= 0
- || EVP_PKEY_CTX_set_hkdf_md(pctx, md) <= 0
- || EVP_PKEY_CTX_set1_hkdf_key(pctx, secret, hashlen) <= 0
- || EVP_PKEY_CTX_add1_hkdf_info(pctx, hkdflabel, hkdflabellen) <= 0
- || EVP_PKEY_derive(pctx, out, &outlen) <= 0;
- 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;
- }
- /*
- * Given a |secret| generate a |key| of length |keylen| bytes. Returns 1 on
- * success 0 on failure.
- */
- int tls13_derive_key(SSL *s, const EVP_MD *md, const unsigned char *secret,
- unsigned char *key, size_t keylen)
- {
- #ifdef CHARSET_EBCDIC
- static const unsigned char keylabel[] ={ 0x6B, 0x65, 0x79, 0x00 };
- #else
- static const unsigned char keylabel[] = "key";
- #endif
- 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 *s, const EVP_MD *md, const unsigned char *secret,
- unsigned char *iv, size_t ivlen)
- {
- #ifdef CHARSET_EBCDIC
- static const unsigned char ivlabel[] = { 0x69, 0x76, 0x00 };
- #else
- static const unsigned char ivlabel[] = "iv";
- #endif
- return tls13_hkdf_expand(s, md, secret, ivlabel, sizeof(ivlabel) - 1,
- NULL, 0, iv, ivlen, 1);
- }
- int tls13_derive_finishedkey(SSL *s, const EVP_MD *md,
- const unsigned char *secret,
- unsigned char *fin, size_t finlen)
- {
- #ifdef CHARSET_EBCDIC
- static const unsigned char finishedlabel[] = { 0x66, 0x69, 0x6E, 0x69, 0x73, 0x68, 0x65, 0x64, 0x00 };
- #else
- static const unsigned char finishedlabel[] = "finished";
- #endif
- 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 *s, const EVP_MD *md,
- const unsigned char *prevsecret,
- const unsigned char *insecret,
- size_t insecretlen,
- unsigned char *outsecret)
- {
- size_t mdlen, prevsecretlen;
- int mdleni;
- int ret;
- EVP_PKEY_CTX *pctx = EVP_PKEY_CTX_new_id(EVP_PKEY_HKDF, NULL);
- #ifdef CHARSET_EBCDIC
- static const char derived_secret_label[] = { 0x64, 0x65, 0x72, 0x69, 0x76, 0x65, 0x64, 0x00 };
- #else
- static const char derived_secret_label[] = "derived";
- #endif
- unsigned char preextractsec[EVP_MAX_MD_SIZE];
- if (pctx == NULL) {
- SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS13_GENERATE_SECRET,
- ERR_R_INTERNAL_ERROR);
- return 0;
- }
- 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;
- insecretlen = mdlen;
- }
- if (prevsecret == NULL) {
- 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;
- }
- ret = EVP_PKEY_derive_init(pctx) <= 0
- || EVP_PKEY_CTX_hkdf_mode(pctx, EVP_PKEY_HKDEF_MODE_EXTRACT_ONLY)
- <= 0
- || EVP_PKEY_CTX_set_hkdf_md(pctx, md) <= 0
- || EVP_PKEY_CTX_set1_hkdf_key(pctx, insecret, insecretlen) <= 0
- || EVP_PKEY_CTX_set1_hkdf_salt(pctx, prevsecret, prevsecretlen)
- <= 0
- || 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;
- }
- /*
- * 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 *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 *s, unsigned char *out,
- unsigned char *prev, size_t prevlen,
- size_t *secret_size)
- {
- 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);
- }
- /*
- * Generates the mac for the Finished message. Returns the length of the MAC or
- * 0 on error.
- */
- size_t tls13_final_finish_mac(SSL *s, const char *str, size_t slen,
- unsigned char *out)
- {
- const EVP_MD *md = ssl_handshake_md(s);
- unsigned char hash[EVP_MAX_MD_SIZE];
- size_t hashlen, ret = 0;
- EVP_PKEY *key = NULL;
- EVP_MD_CTX *ctx = EVP_MD_CTX_new();
- 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_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) {
- SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS13_FINAL_FINISH_MAC,
- ERR_R_INTERNAL_ERROR);
- goto err;
- }
- ret = hashlen;
- err:
- EVP_PKEY_free(key);
- EVP_MD_CTX_free(ctx);
- return ret;
- }
- /*
- * 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 *s)
- {
- const EVP_CIPHER *c;
- const EVP_MD *hash;
- s->session->cipher = s->s3->tmp.new_cipher;
- 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;
- }
- s->s3->tmp.new_sym_enc = c;
- s->s3->tmp.new_hash = hash;
- return 1;
- }
- 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,
- const unsigned char *label,
- size_t labellen, unsigned char *secret,
- unsigned char *iv, EVP_CIPHER_CTX *ciph_ctx)
- {
- unsigned char key[EVP_MAX_KEY_LENGTH];
- size_t ivlen, keylen, taglen;
- 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, 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 != 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, SSL_F_DERIVE_SECRET_KEY_AND_IV,
- ERR_R_EVP_LIB);
- goto err;
- }
- if (algenc & (SSL_AES128CCM8 | SSL_AES256CCM8))
- taglen = EVP_CCM8_TLS_TAG_LEN;
- else
- taglen = EVP_CCM_TLS_TAG_LEN;
- } else {
- ivlen = EVP_CIPHER_iv_length(ciph);
- taglen = 0;
- }
- if (!tls13_derive_key(s, md, secret, key, keylen)
- || !tls13_derive_iv(s, md, secret, iv, ivlen)) {
- /* SSLfatal() already called */
- goto err;
- }
- 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) {
- SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_DERIVE_SECRET_KEY_AND_IV,
- ERR_R_EVP_LIB);
- goto err;
- }
- return 1;
- err:
- OPENSSL_cleanse(key, sizeof(key));
- return 0;
- }
- int tls13_change_cipher_state(SSL *s, int which)
- {
- #ifdef CHARSET_EBCDIC
- static const unsigned char client_early_traffic[] = {0x63, 0x20, 0x65, 0x20, /*traffic*/0x74, 0x72, 0x61, 0x66, 0x66, 0x69, 0x63, 0x00};
- static const unsigned char client_handshake_traffic[] = {0x63, 0x20, 0x68, 0x73, 0x20, /*traffic*/0x74, 0x72, 0x61, 0x66, 0x66, 0x69, 0x63, 0x00};
- static const unsigned char client_application_traffic[] = {0x63, 0x20, 0x61, 0x70, 0x20, /*traffic*/0x74, 0x72, 0x61, 0x66, 0x66, 0x69, 0x63, 0x00};
- static const unsigned char server_handshake_traffic[] = {0x73, 0x20, 0x68, 0x73, 0x20, /*traffic*/0x74, 0x72, 0x61, 0x66, 0x66, 0x69, 0x63, 0x00};
- static const unsigned char server_application_traffic[] = {0x73, 0x20, 0x61, 0x70, 0x20, /*traffic*/0x74, 0x72, 0x61, 0x66, 0x66, 0x69, 0x63, 0x00};
- static const unsigned char exporter_master_secret[] = {0x65, 0x78, 0x70, 0x20, /* master*/ 0x6D, 0x61, 0x73, 0x74, 0x65, 0x72, 0x00};
- static const unsigned char resumption_master_secret[] = {0x72, 0x65, 0x73, 0x20, /* master*/ 0x6D, 0x61, 0x73, 0x74, 0x65, 0x72, 0x00};
- static const unsigned char early_exporter_master_secret[] = {0x65, 0x20, 0x65, 0x78, 0x70, 0x20, /* master*/ 0x6D, 0x61, 0x73, 0x74, 0x65, 0x72, 0x00};
- #else
- 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";
- #endif
- unsigned char *iv;
- 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;
- EVP_CIPHER_CTX *ciph_ctx;
- size_t finsecretlen = 0;
- const unsigned char *label;
- size_t labellen, hashlen = 0;
- int ret = 0;
- const EVP_MD *md = NULL;
- const EVP_CIPHER *cipher = NULL;
- if (which & SSL3_CC_READ) {
- if (s->enc_read_ctx != NULL) {
- EVP_CIPHER_CTX_reset(s->enc_read_ctx);
- } else {
- s->enc_read_ctx = EVP_CIPHER_CTX_new();
- if (s->enc_read_ctx == NULL) {
- SSLfatal(s, SSL_AD_INTERNAL_ERROR,
- SSL_F_TLS13_CHANGE_CIPHER_STATE, ERR_R_MALLOC_FAILURE);
- goto err;
- }
- }
- ciph_ctx = s->enc_read_ctx;
- iv = s->read_iv;
- 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) {
- SSLfatal(s, SSL_AD_INTERNAL_ERROR,
- SSL_F_TLS13_CHANGE_CIPHER_STATE, ERR_R_MALLOC_FAILURE);
- goto err;
- }
- }
- ciph_ctx = s->enc_write_ctx;
- iv = s->write_iv;
- RECORD_LAYER_reset_write_sequence(&s->rlayer);
- }
- 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_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) {
- SSLfatal(s, SSL_AD_INTERNAL_ERROR,
- SSL_F_TLS13_CHANGE_CIPHER_STATE, 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,
- SSL_F_TLS13_CHANGE_CIPHER_STATE, ERR_R_MALLOC_FAILURE);
- goto err;
- }
- cipher = EVP_get_cipherbynid(SSL_CIPHER_get_cipher_nid(sslcipher));
- md = ssl_md(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,
- 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;
- finsecretlen = EVP_MD_size(ssl_handshake_md(s));
- 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_size(ssl_handshake_md(s));
- 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;
- }
- }
- 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) {
- 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, finsecretlen)) {
- /* 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 sending)
- {
- #ifdef CHARSET_EBCDIC
- static const unsigned char application_traffic[] = { 0x74, 0x72 ,0x61 ,0x66 ,0x66 ,0x69 ,0x63 ,0x20 ,0x75 ,0x70 ,0x64, 0x00};
- #else
- static const unsigned char application_traffic[] = "traffic upd";
- #endif
- const EVP_MD *md = ssl_handshake_md(s);
- size_t hashlen = EVP_MD_size(md);
- unsigned char *insecret, *iv;
- unsigned char secret[EVP_MAX_MD_SIZE];
- EVP_CIPHER_CTX *ciph_ctx;
- int ret = 0;
- if (s->server == sending)
- insecret = s->server_app_traffic_secret;
- else
- insecret = s->client_app_traffic_secret;
- 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);
- } else {
- iv = s->read_iv;
- ciph_ctx = s->enc_read_ctx;
- RECORD_LAYER_reset_read_sequence(&s->rlayer);
- }
- 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)) {
- /* 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));
- 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 *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];
- #ifdef CHARSET_EBCDIC
- static const unsigned char exporterlabel[] = {0x65, 0x78, 0x70, 0x6F, 0x72, 0x74, 0x65, 0x72, 0x00};
- #else
- static const unsigned char exporterlabel[] = "exporter";
- #endif
- 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)
- {
- #ifdef CHARSET_EBCDIC
- static const unsigned char exporterlabel[] = {0x65, 0x78, 0x70, 0x6F, 0x72, 0x74, 0x65, 0x72, 0x00};
- #else
- static const unsigned char exporterlabel[] = "exporter";
- #endif
- 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;
- }
|