* the location pointed to be |out|. The |hash| value may be NULL. Returns 1 on
* success 0 on failure.
*/
-static int tls13_hkdf_expand(SSL *s, const unsigned char *secret,
+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 label_prefix[] = "TLS 1.3, ";
- const EVP_MD *md = ssl_handshake_md(s);
EVP_PKEY_CTX *pctx = EVP_PKEY_CTX_new_id(EVP_PKEY_HKDF, NULL);
int ret;
size_t hkdflabellen;
|| !WPACKET_sub_memcpy_u8(&pkt, hash, (hash == NULL) ? 0 : hashlen)
|| !WPACKET_get_total_written(&pkt, &hkdflabellen)
|| !WPACKET_finish(&pkt)) {
+ EVP_PKEY_CTX_free(pctx);
WPACKET_cleanup(&pkt);
return 0;
}
return ret == 0;
}
-/*
- * Given a input secret |insecret| and a |label| of length |labellen|, derive a
- * new |secret|. This will be the length of the current hash output size and
- * will be based on the current state of the handshake hashes. Returns 1 on
- * success 0 on failure.
- */
-int tls13_derive_secret(SSL *s, const unsigned char *insecret,
- const unsigned char *label, size_t labellen,
- unsigned char *secret)
-{
- unsigned char hash[EVP_MAX_MD_SIZE];
- size_t hashlen;
-
- if (!ssl3_digest_cached_records(s, 1))
- return 0;
-
- if (!ssl_handshake_hash(s, hash, sizeof(hash), &hashlen))
- return 0;
-
- return tls13_hkdf_expand(s, insecret, label, labellen, hash, secret,
- hashlen);
-}
-
/*
* Given a |secret| generate a |key| of length |keylen| bytes. Returns 1 on
* success 0 on failure.
*/
-int tls13_derive_key(SSL *s, const unsigned char *secret, unsigned char *key,
- size_t keylen)
+int tls13_derive_key(SSL *s, const EVP_MD *md, const unsigned char *secret,
+ unsigned char *key, size_t keylen)
{
static const unsigned char keylabel[] = "key";
- return tls13_hkdf_expand(s, secret, keylabel, sizeof(keylabel) - 1, NULL,
- key, keylen);
+ return tls13_hkdf_expand(s, md, secret, keylabel, sizeof(keylabel) - 1,
+ NULL, key, keylen);
}
/*
* Given a |secret| generate an |iv| of length |ivlen| bytes. Returns 1 on
* success 0 on failure.
*/
-int tls13_derive_iv(SSL *s, const unsigned char *secret, unsigned char *iv,
- size_t ivlen)
+int tls13_derive_iv(SSL *s, const EVP_MD *md, const unsigned char *secret,
+ unsigned char *iv, size_t ivlen)
{
static const unsigned char ivlabel[] = "iv";
- return tls13_hkdf_expand(s, secret, ivlabel, sizeof(ivlabel) - 1, NULL,
- iv, ivlen);
+ return tls13_hkdf_expand(s, md, secret, ivlabel, sizeof(ivlabel) - 1,
+ NULL, iv, ivlen);
}
-static int tls13_derive_finishedkey(SSL *s, const unsigned char *secret,
- unsigned char *fin, size_t finlen)
+int tls13_derive_finishedkey(SSL *s, const EVP_MD *md,
+ const unsigned char *secret,
+ unsigned char *fin, size_t finlen)
{
static const unsigned char finishedlabel[] = "finished";
- return tls13_hkdf_expand(s, secret, finishedlabel,
+ return tls13_hkdf_expand(s, md, secret, finishedlabel,
sizeof(finishedlabel) - 1, NULL, fin, finlen);
}
* length |insecretlen|, generate a new secret and store it in the location
* pointed to by |outsecret|. Returns 1 on success 0 on failure.
*/
-static int tls13_generate_secret(SSL *s, const unsigned char *prevsecret,
- const unsigned char *insecret,
- size_t insecretlen,
- unsigned char *outsecret)
+int tls13_generate_secret(SSL *s, const EVP_MD *md,
+ const unsigned char *prevsecret,
+ const unsigned char *insecret,
+ size_t insecretlen,
+ unsigned char *outsecret)
{
- const EVP_MD *md = ssl_handshake_md(s);
size_t mdlen, prevsecretlen;
int ret;
EVP_PKEY_CTX *pctx = EVP_PKEY_CTX_new_id(EVP_PKEY_HKDF, NULL);
+ const char *derived_secret_label = "derived secret";
+ unsigned char preextractsec[EVP_MAX_MD_SIZE];
if (pctx == NULL)
return 0;
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) {
+ EVP_MD_CTX_free(mctx);
+ 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,
+ preextractsec, mdlen))
+ return 0;
+
+ prevsecret = preextractsec;
prevsecretlen = mdlen;
}
<= 0;
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 early
- * secret. Returns 1 on success 0 on failure.
- */
-int tls13_generate_early_secret(SSL *s, const unsigned char *insecret,
- size_t insecretlen)
-{
- return tls13_generate_secret(s, NULL, insecret, insecretlen,
- (unsigned char *)&s->early_secret);
-}
-
/*
* Given an input secret |insecret| of length |insecretlen| generate the
* handshake secret. This requires the early secret to already have been
int tls13_generate_handshake_secret(SSL *s, const unsigned char *insecret,
size_t insecretlen)
{
- return tls13_generate_secret(s, s->early_secret, insecret, insecretlen,
+ return tls13_generate_secret(s, ssl_handshake_md(s), s->early_secret,
+ insecret, insecretlen,
(unsigned char *)&s->handshake_secret);
}
unsigned char *prev, size_t prevlen,
size_t *secret_size)
{
- *secret_size = EVP_MD_size(ssl_handshake_md(s));
- return tls13_generate_secret(s, prev, NULL, 0, out);
+ const EVP_MD *md = ssl_handshake_md(s);
+
+ *secret_size = EVP_MD_size(md);
+ return tls13_generate_secret(s, md, prev, NULL, 0, out);
}
/*
return 1;
}
+static int derive_secret_key_and_iv(SSL *s, int send, 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;
+ size_t hashlen = EVP_MD_size(md);
+
+ if (!tls13_hkdf_expand(s, md, insecret, label, labellen, hash, secret,
+ hashlen)) {
+ SSLerr(SSL_F_DERIVE_SECRET_KEY_AND_IV, ERR_R_INTERNAL_ERROR);
+ 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) {
+ /* 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;
+ } 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)) {
+ SSLerr(SSL_F_DERIVE_SECRET_KEY_AND_IV, ERR_R_INTERNAL_ERROR);
+ goto err;
+ }
+
+ if (EVP_CipherInit_ex(ciph_ctx, ciph, NULL, NULL, NULL, send) <= 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);
+ 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));
+ return 0;
+}
+
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[] =
"server handshake traffic secret";
static const unsigned char server_application_traffic[] =
"server application traffic secret";
- unsigned char key[EVP_MAX_KEY_LENGTH];
- unsigned char iv[EVP_MAX_IV_LENGTH];
+ static const unsigned char resumption_master_secret[] =
+ "resumption master secret";
+ 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;
- const EVP_CIPHER *ciph = s->s3->tmp.new_sym_enc;;
- size_t ivlen, keylen, finsecretlen;
+ size_t finsecretlen = 0;
const unsigned char *label;
- size_t labellen;
+ 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) {
}
}
ciph_ctx = s->enc_read_ctx;
+ iv = s->read_iv;
RECORD_LAYER_reset_read_sequence(&s->rlayer);
} else {
}
}
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_HANDSHAKE) {
+ 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) {
+ SSLerr(SSL_F_TLS13_CHANGE_CIPHER_STATE,
+ SSL_R_BAD_HANDSHAKE_LENGTH);
+ goto err;
+ }
+ if (sslcipher == NULL) {
+ SSLerr(SSL_F_TLS13_CHANGE_CIPHER_STATE, ERR_R_INTERNAL_ERROR);
+ 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) {
+ SSLerr(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)) {
+ SSLerr(SSL_F_TLS13_CHANGE_CIPHER_STATE, ERR_R_INTERNAL_ERROR);
+ EVP_MD_CTX_free(mdctx);
+ goto err;
+ }
+ hashlen = hashlenui;
+ EVP_MD_CTX_free(mdctx);
+ } else if (which & SSL3_CC_HANDSHAKE) {
insecret = s->handshake_secret;
finsecret = s->client_finished_secret;
- finsecretlen = sizeof(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 hanshake 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->session->master_key;
+ 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 = sizeof(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->session->master_key;
+ insecret = s->master_secret;
label = server_application_traffic;
labellen = sizeof(server_application_traffic) - 1;
+ log_label = SERVER_APPLICATION_LABEL;
}
}
- if (!tls13_derive_secret(s, insecret, label, labellen, secret)) {
- SSLerr(SSL_F_TLS13_CHANGE_CIPHER_STATE, ERR_R_INTERNAL_ERROR);
- goto err;
+ 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)) {
+ SSLerr(SSL_F_TLS13_CHANGE_CIPHER_STATE, ERR_R_INTERNAL_ERROR);
+ goto err;
+ }
}
- /* TODO(size_t): convert me */
- keylen = EVP_CIPHER_key_length(ciph);
+ /*
+ * 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, s->session->master_key, hashlen)) {
+ SSLerr(SSL_F_TLS13_CHANGE_CIPHER_STATE, ERR_R_INTERNAL_ERROR);
+ goto err;
+ }
+ s->session->master_key_length = hashlen;
+ }
- if (EVP_CIPHER_mode(ciph) == EVP_CIPH_GCM_MODE)
- ivlen = EVP_GCM_TLS_FIXED_IV_LEN;
- else if (EVP_CIPHER_mode(ciph) == EVP_CIPH_CCM_MODE)
- ivlen = EVP_CCM_TLS_FIXED_IV_LEN;
- else
- ivlen = EVP_CIPHER_iv_length(ciph);
+ if (!derive_secret_key_and_iv(s, which & SSL3_CC_WRITE, md, cipher,
+ insecret, hash, label, labellen, secret, iv,
+ ciph_ctx)) {
+ goto err;
+ }
+
+ if (label == server_application_traffic)
+ memcpy(s->server_app_traffic_secret, secret, hashlen);
+ else if (label == client_application_traffic)
+ memcpy(s->client_app_traffic_secret, secret, hashlen);
- if (!tls13_derive_key(s, secret, key, keylen)
- || !tls13_derive_iv(s, secret, iv, ivlen)
- || (finsecret != NULL && !tls13_derive_finishedkey(s, secret,
- finsecret,
- finsecretlen))) {
+ if (!ssl_log_secret(s, log_label, secret, hashlen)) {
SSLerr(SSL_F_TLS13_CHANGE_CIPHER_STATE, ERR_R_INTERNAL_ERROR);
goto err;
}
- if (EVP_CIPHER_mode(ciph) == EVP_CIPH_GCM_MODE) {
- if (!EVP_CipherInit_ex(ciph_ctx, ciph, NULL, key, NULL,
- (which & SSL3_CC_WRITE))
- || !EVP_CIPHER_CTX_ctrl(ciph_ctx, EVP_CTRL_GCM_SET_IV_FIXED,
- (int)ivlen, iv)) {
- SSLerr(SSL_F_TLS13_CHANGE_CIPHER_STATE, ERR_R_EVP_LIB);
- goto err;
- }
- } else if (EVP_CIPHER_mode(ciph) == EVP_CIPH_CCM_MODE) {
- int taglen;
-
- if (s->s3->tmp.new_cipher->algorithm_enc
- & (SSL_AES128CCM8 | SSL_AES256CCM8))
- taglen = 8;
- else
- taglen = 16;
- if (!EVP_CipherInit_ex(ciph_ctx, ciph, NULL, NULL, NULL,
- (which & SSL3_CC_WRITE))
- || !EVP_CIPHER_CTX_ctrl(ciph_ctx, EVP_CTRL_AEAD_SET_IVLEN, 12,
- NULL)
- || !EVP_CIPHER_CTX_ctrl(ciph_ctx, EVP_CTRL_AEAD_SET_TAG, taglen,
- NULL)
- || !EVP_CIPHER_CTX_ctrl(ciph_ctx, EVP_CTRL_CCM_SET_IV_FIXED,
- (int)ivlen, iv)
- || !EVP_CipherInit_ex(ciph_ctx, NULL, NULL, key, NULL, -1)) {
- SSLerr(SSL_F_TLS13_CHANGE_CIPHER_STATE, ERR_R_EVP_LIB);
- goto err;
- }
- } else {
- if (!EVP_CipherInit_ex(ciph_ctx, ciph, NULL, key, iv,
- (which & SSL3_CC_WRITE))) {
- SSLerr(SSL_F_TLS13_CHANGE_CIPHER_STATE, ERR_R_EVP_LIB);
- 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);
+ goto err;
}
-#ifdef OPENSSL_SSL_TRACE_CRYPTO
- if (s->msg_callback) {
- int wh = which & SSL3_CC_WRITE ? TLS1_RT_CRYPTO_WRITE : 0;
+ ret = 1;
+ err:
+ OPENSSL_cleanse(secret, sizeof(secret));
+ return ret;
+}
- if (ciph->key_len)
- s->msg_callback(2, s->version, wh | TLS1_RT_CRYPTO_KEY,
- key, ciph->key_len, s, s->msg_callback_arg);
- if (ivlen) {
- if (EVP_CIPHER_mode(ciph) == EVP_CIPH_GCM_MODE)
- wh |= TLS1_RT_CRYPTO_FIXED_IV;
- else
- wh |= TLS1_RT_CRYPTO_IV;
- s->msg_callback(2, s->version, wh, iv, ivlen, s,
- s->msg_callback_arg);
- }
+int tls13_update_key(SSL *s, int send)
+{
+ static const unsigned char application_traffic[] =
+ "application traffic secret";
+ 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 == send)
+ insecret = s->server_app_traffic_secret;
+ else
+ insecret = s->client_app_traffic_secret;
+
+ if (send) {
+ 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);
}
-#endif
- OPENSSL_cleanse(secret, sizeof(secret));
- OPENSSL_cleanse(key, sizeof(key));
- OPENSSL_cleanse(iv, sizeof(iv));
- return 1;
+ if (!derive_secret_key_and_iv(s, send, ssl_handshake_md(s),
+ s->s3->tmp.new_sym_enc, insecret, NULL,
+ application_traffic,
+ sizeof(application_traffic) - 1, secret, iv,
+ ciph_ctx))
+ goto err;
+ memcpy(insecret, secret, hashlen);
+
+ ret = 1;
err:
OPENSSL_cleanse(secret, sizeof(secret));
- OPENSSL_cleanse(key, sizeof(key));
- OPENSSL_cleanse(iv, sizeof(iv));
- return 0;
+ return ret;
+}
+
+int tls13_alert_code(int code)
+{
+ if (code == SSL_AD_MISSING_EXTENSION || code == SSL_AD_END_OF_EARLY_DATA)
+ return code;
+
+ return tls1_alert_code(code);
}