/*
* Save the ALPN extension in a ClientHello.|pkt| holds the contents of the ALPN
* extension, not including type and length. |al| is a pointer to the alert
* value to send in the event of a failure. Returns: 1 on success, 0 on error.
*/
int tls_parse_ctos_alpn(SSL *s, PACKET *pkt, unsigned int context, X509 *x,
size_t chainidx, int *al)
{
PACKET protocol_list, save_protocol_list, protocol;
if (!SSL_IS_FIRST_HANDSHAKE(s))
return 1;
if (!PACKET_as_length_prefixed_2(pkt, &protocol_list)
|| PACKET_remaining(&protocol_list) < 2) {
*al = SSL_AD_DECODE_ERROR;
return 0;
}
save_protocol_list = protocol_list;
do {
/* Protocol names can't be empty. */
if (!PACKET_get_length_prefixed_1(&protocol_list, &protocol)
|| PACKET_remaining(&protocol) == 0) {
*al = SSL_AD_DECODE_ERROR;
return 0;
}
} while (PACKET_remaining(&protocol_list) != 0);
OPENSSL_free(s->s3->alpn_proposed);
s->s3->alpn_proposed = NULL;
s->s3->alpn_proposed_len = 0;
if (!PACKET_memdup(&save_protocol_list,
&s->s3->alpn_proposed, &s->s3->alpn_proposed_len)) {
*al = SSL_AD_INTERNAL_ERROR;
return 0;
}
return 1;
}
int tls_parse_ctos_npn(SSL *s, PACKET *pkt, unsigned int context, X509 *x,
size_t chainidx, int *al)
{
/*
* We shouldn't accept this extension on a
* renegotiation.
*/
if (SSL_IS_FIRST_HANDSHAKE(s))
s->s3->npn_seen = 1;
return 1;
}
/*
* 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;
}
int tls_parse_stoc_npn(SSL *s, PACKET *pkt, unsigned int context, X509 *x,
size_t chainidx, int *al)
{
unsigned char *selected;
unsigned char selected_len;
PACKET tmppkt;
/* Check if we are in a renegotiation. If so ignore this extension */
if (!SSL_IS_FIRST_HANDSHAKE(s))
return 1;
/* We must have requested it. */
if (s->ctx->ext.npn_select_cb == NULL) {
*al = SSL_AD_UNSUPPORTED_EXTENSION;
return 0;
}
/* The data must be valid */
tmppkt = *pkt;
if (!ssl_next_proto_validate(&tmppkt)) {
*al = SSL_AD_DECODE_ERROR;
return 0;
}
if (s->ctx->ext.npn_select_cb(s, &selected, &selected_len,
PACKET_data(pkt),
PACKET_remaining(pkt),
s->ctx->ext.npn_select_cb_arg) !=
SSL_TLSEXT_ERR_OK) {
*al = SSL_AD_INTERNAL_ERROR;
return 0;
}
/*
* Could be non-NULL if server has sent multiple NPN extensions in
* a single Serverhello
*/
OPENSSL_free(s->ext.npn);
s->ext.npn = OPENSSL_malloc(selected_len);
if (s->ext.npn == NULL) {
*al = SSL_AD_INTERNAL_ERROR;
return 0;
}
memcpy(s->ext.npn, selected, selected_len);
s->ext.npn_len = selected_len;
s->s3->npn_seen = 1;
return 1;
}
int tls_construct_ctos_npn(SSL *s, WPACKET *pkt, unsigned int context, X509 *x,
size_t chainidx, int *al)
{
if (s->ctx->ext.npn_select_cb == NULL || !SSL_IS_FIRST_HANDSHAKE(s))
return 1;
/*
* The client advertises an empty extension to indicate its support
* for Next Protocol Negotiation
*/
if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_next_proto_neg)
|| !WPACKET_put_bytes_u16(pkt, 0)) {
SSLerr(SSL_F_TLS_CONSTRUCT_CTOS_NPN, ERR_R_INTERNAL_ERROR);
return 0;
}
return 1;
}
int tls_construct_ctos_alpn(SSL *s, WPACKET *pkt, unsigned int context, X509 *x,
size_t chainidx, int *al)
{
s->s3->alpn_sent = 0;
if (s->ext.alpn == NULL || !SSL_IS_FIRST_HANDSHAKE(s))
return 1;
if (!WPACKET_put_bytes_u16(pkt,
TLSEXT_TYPE_application_layer_protocol_negotiation)
/* Sub-packet ALPN extension */
|| !WPACKET_start_sub_packet_u16(pkt)
|| !WPACKET_sub_memcpy_u16(pkt, s->ext.alpn, s->ext.alpn_len)
|| !WPACKET_close(pkt)) {
SSLerr(SSL_F_TLS_CONSTRUCT_CTOS_ALPN, ERR_R_INTERNAL_ERROR);
return 0;
}
s->s3->alpn_sent = 1;
return 1;
}
