|| !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;
}
* 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, ssl_handshake_md(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, ssl_handshake_md(s), secret, ivlabel,
- sizeof(ivlabel) - 1, NULL, iv, ivlen);
+ return tls13_hkdf_expand(s, md, secret, ivlabel, sizeof(ivlabel) - 1,
+ NULL, iv, ivlen);
}
int tls13_derive_finishedkey(SSL *s, const EVP_MD *md,
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;
}
return 1;
}
-static int derive_secret_key_and_iv(SSL *s, int send,
+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,
{
unsigned char key[EVP_MAX_KEY_LENGTH];
size_t ivlen, keylen, taglen;
- const EVP_MD *md = ssl_handshake_md(s);
size_t hashlen = EVP_MD_size(md);
- const EVP_CIPHER *ciph = s->s3->tmp.new_sym_enc;
if (!tls13_hkdf_expand(s, md, insecret, label, labellen, hash, secret,
hashlen)) {
/* 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;
taglen = 0;
}
- if (!tls13_derive_key(s, secret, key, keylen)
- || !tls13_derive_iv(s, secret, iv, ivlen)) {
+ 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;
}
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[] =
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) {
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 = 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->master_secret;
label = client_application_traffic;
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;
}
}
- 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;
+ 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;
+ }
}
/*
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
s->session->master_key_length = hashlen;
}
- if (!derive_secret_key_and_iv(s, which & SSL3_CC_WRITE, insecret, hash,
- label, labellen, secret, iv, ciph_ctx)) {
+ if (!derive_secret_key_and_iv(s, which & SSL3_CC_WRITE, md, cipher,
+ insecret, hash, label, labellen, secret, iv,
+ ciph_ctx)) {
goto err;
}
RECORD_LAYER_reset_read_sequence(&s->rlayer);
}
- if (!derive_secret_key_and_iv(s, send, insecret, NULL, application_traffic,
+ 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;