/* Always filled with zeros */
static const unsigned char default_zeros[EVP_MAX_MD_SIZE];
-static const unsigned char keylabel[] = "key";
-static const unsigned char ivlabel[] = "iv";
-
/*
* 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.
+ * 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,
const unsigned char *label, size_t labellen,
/*
* 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.
+ * 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,
}
/*
- * Given a |secret| generate a |key| of length |keylen| bytes.
- *
- * Returns 1 on success 0 on failure.
+ * 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)
{
+ static const unsigned char keylabel[] = "key";
+
return tls13_hkdf_expand(s, 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.
+ * 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)
{
+ static const unsigned char ivlabel[] = "iv";
+
return tls13_hkdf_expand(s, 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)
+{
+ static const unsigned char finishedlabel[] = "finished";
+
+ return tls13_hkdf_expand(s, secret, finishedlabel,
+ sizeof(finishedlabel) - 1, NULL, fin, finlen);
+}
+
/*
* 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.
+ * 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,
/*
* Given an input secret |insecret| of length |insecretlen| generate the early
- * secret.
- *
- * Returns 1 on success 0 on failure.
+ * secret. Returns 1 on success 0 on failure.
*/
int tls13_generate_early_secret(SSL *s, const unsigned char *insecret,
size_t insecretlen)
/*
* 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.
+ * generated. Returns 1 on success 0 on failure.
*/
int tls13_generate_handshake_secret(SSL *s, const unsigned char *insecret,
size_t insecretlen)
/*
* 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.
+ * 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,
return tls13_generate_secret(s, 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))
+ 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 (key == NULL
+ || ctx == NULL
+ || EVP_DigestSignInit(ctx, NULL, md, NULL, key) <= 0
+ || EVP_DigestSignUpdate(ctx, hash, hashlen) <= 0
+ || EVP_DigestSignFinal(ctx, out, &hashlen) <= 0)
+ 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;
+ 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);
+ return 0;
+ }
+
+ s->s3->tmp.new_sym_enc = c;
+ s->s3->tmp.new_hash = hash;
+
+ return 1;
+}
+
+int tls13_change_cipher_state(SSL *s, int which)
+{
+ 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";
+ unsigned char key[EVP_MAX_KEY_LENGTH];
+ unsigned char iv[EVP_MAX_IV_LENGTH];
+ unsigned char secret[EVP_MAX_MD_SIZE];
+ unsigned char *insecret;
+ unsigned char *finsecret = NULL;
+ EVP_CIPHER_CTX *ciph_ctx;
+ const EVP_CIPHER *ciph = s->s3->tmp.new_sym_enc;
+ size_t ivlen, keylen, finsecretlen = 0;
+ const unsigned char *label;
+ size_t labellen;
+ int ret = 0;
+
+ 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) {
+ SSLerr(SSL_F_TLS13_CHANGE_CIPHER_STATE, ERR_R_MALLOC_FAILURE);
+ goto err;
+ }
+ }
+ ciph_ctx = s->enc_read_ctx;
+
+ RECORD_LAYER_reset_read_sequence(&s->rlayer);
+ } else {
+ 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);
+ goto err;
+ }
+ }
+ ciph_ctx = s->enc_write_ctx;
+
+ 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) {
+ insecret = s->handshake_secret;
+ finsecret = s->client_finished_secret;
+ finsecretlen = sizeof(s->client_finished_secret);
+ label = client_handshake_traffic;
+ labellen = sizeof(client_handshake_traffic) - 1;
+ } else {
+ insecret = s->session->master_key;
+ label = client_application_traffic;
+ labellen = sizeof(client_application_traffic) - 1;
+ }
+ } else {
+ if (which & SSL3_CC_HANDSHAKE) {
+ insecret = s->handshake_secret;
+ finsecret = s->server_finished_secret;
+ finsecretlen = sizeof(s->server_finished_secret);
+ label = server_handshake_traffic;
+ labellen = sizeof(server_handshake_traffic) - 1;
+ } else {
+ insecret = s->session->master_key;
+ label = server_application_traffic;
+ labellen = sizeof(server_application_traffic) - 1;
+ }
+ }
+
+ if (!tls13_derive_secret(s, insecret, label, labellen, secret)) {
+ SSLerr(SSL_F_TLS13_CHANGE_CIPHER_STATE, ERR_R_INTERNAL_ERROR);
+ goto err;
+ }
+
+ /* TODO(size_t): convert me */
+ keylen = EVP_CIPHER_key_length(ciph);
+
+ 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 (!tls13_derive_key(s, secret, key, keylen)
+ || !tls13_derive_iv(s, secret, iv, ivlen)
+ || (finsecret != NULL && !tls13_derive_finishedkey(s, secret,
+ finsecret,
+ finsecretlen))) {
+ 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;
+ }
+ }
+
+#ifdef OPENSSL_SSL_TRACE_CRYPTO
+ if (s->msg_callback) {
+ int wh = which & SSL3_CC_WRITE ? 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);
+ 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);
+ }
+ }
+#endif
+
+ ret = 1;
+
+ err:
+ OPENSSL_cleanse(secret, sizeof(secret));
+ OPENSSL_cleanse(key, sizeof(key));
+ OPENSSL_cleanse(iv, sizeof(iv));
+ return ret;
+}
projects / openssl.git / blobdiff