/*-
* The servername extension is treated as follows:
*
* - Only the hostname type is supported with a maximum length of 255.
* - The servername is rejected if too long or if it contains zeros,
* in which case an fatal alert is generated.
* - The servername field is maintained together with the session cache.
* - When a session is resumed, the servername call back invoked in order
* to allow the application to position itself to the right context.
* - The servername is acknowledged if it is new for a session or when
* it is identical to a previously used for the same session.
* Applications can control the behaviour. They can at any time
* set a 'desirable' servername for a new SSL object. This can be the
* case for example with HTTPS when a Host: header field is received and
* a renegotiation is requested. In this case, a possible servername
* presented in the new client hello is only acknowledged if it matches
* the value of the Host: field.
* - Applications must use SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION
* if they provide for changing an explicit servername context for the
* session, i.e. when the session has been established with a servername
* extension.
* - On session reconnect, the servername extension may be absent.
*/
int tls_parse_ctos_server_name(SSL *s, PACKET *pkt, int *al)
{
unsigned int servname_type;
PACKET sni, hostname;
if (!PACKET_as_length_prefixed_2(pkt, &sni)
/* ServerNameList must be at least 1 byte long. */
|| PACKET_remaining(&sni) == 0) {
*al = SSL_AD_DECODE_ERROR;
return 0;
}
/*
* Although the server_name extension was intended to be
* extensible to new name types, RFC 4366 defined the
* syntax inextensibly and OpenSSL 1.0.x parses it as
* such.
* RFC 6066 corrected the mistake but adding new name types
* is nevertheless no longer feasible, so act as if no other
* SNI types can exist, to simplify parsing.
*
* Also note that the RFC permits only one SNI value per type,
* i.e., we can only have a single hostname.
*/
if (!PACKET_get_1(&sni, &servname_type)
|| servname_type != TLSEXT_NAMETYPE_host_name
|| !PACKET_as_length_prefixed_2(&sni, &hostname)) {
*al = SSL_AD_DECODE_ERROR;
return 0;
}
if (!s->hit) {
if (PACKET_remaining(&hostname) > TLSEXT_MAXLEN_host_name) {
*al = TLS1_AD_UNRECOGNIZED_NAME;
return 0;
}
if (PACKET_contains_zero_byte(&hostname)) {
*al = TLS1_AD_UNRECOGNIZED_NAME;
return 0;
}
if (!PACKET_strndup(&hostname, &s->session->tlsext_hostname)) {
*al = TLS1_AD_INTERNAL_ERROR;
return 0;
}
s->servername_done = 1;
} else {
/*
* TODO(openssl-team): if the SNI doesn't match, we MUST
* fall back to a full handshake.
*/
s->servername_done = s->session->tlsext_hostname
&& PACKET_equal(&hostname, s->session->tlsext_hostname,
strlen(s->session->tlsext_hostname));
}
return 1;
}
int tls_parse_ctos_supported_groups(SSL *s, PACKET *pkt, unsigned int context,
X509 *x, size_t chainidx, int *al)
{
PACKET supported_groups_list;
/* Each group is 2 bytes and we must have at least 1. */
if (!PACKET_as_length_prefixed_2(pkt, &supported_groups_list)
|| PACKET_remaining(&supported_groups_list) == 0
|| (PACKET_remaining(&supported_groups_list) % 2) != 0) {
*al = SSL_AD_DECODE_ERROR;
return 0;
}
if (!s->hit || SSL_IS_TLS13(s)) {
OPENSSL_free(s->session->ext.supportedgroups);
s->session->ext.supportedgroups = NULL;
s->session->ext.supportedgroups_len = 0;
if (!PACKET_memdup(&supported_groups_list,
&s->session->ext.supportedgroups,
&s->session->ext.supportedgroups_len)) {
*al = SSL_AD_INTERNAL_ERROR;
return 0;
}
}
return 1;
}
/*
* 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;
}
/*
* 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, int *al)
{
PACKET protocol_list, save_protocol_list, protocol;
if (s->s3->tmp.finish_md_len != 0)
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);
if (!PACKET_memdup(&save_protocol_list,
&s->s3->alpn_proposed, &s->s3->alpn_proposed_len)) {
*al = TLS1_AD_INTERNAL_ERROR;
return 0;
}
return 1;
}
int tls_parse_ctos_supported_groups(SSL *s, PACKET *pkt, unsigned int context,
X509 *x, size_t chainidx)
{
PACKET supported_groups_list;
/* Each group is 2 bytes and we must have at least 1. */
if (!PACKET_as_length_prefixed_2(pkt, &supported_groups_list)
|| PACKET_remaining(&supported_groups_list) == 0
|| (PACKET_remaining(&supported_groups_list) % 2) != 0) {
SSLfatal(s, SSL_AD_DECODE_ERROR,
SSL_F_TLS_PARSE_CTOS_SUPPORTED_GROUPS, SSL_R_BAD_EXTENSION);
return 0;
}
if (!s->hit || SSL_IS_TLS13(s)) {
OPENSSL_free(s->session->ext.supportedgroups);
s->session->ext.supportedgroups = NULL;
s->session->ext.supportedgroups_len = 0;
if (!tls1_save_u16(&supported_groups_list,
&s->session->ext.supportedgroups,
&s->session->ext.supportedgroups_len)) {
SSLfatal(s, SSL_AD_INTERNAL_ERROR,
SSL_F_TLS_PARSE_CTOS_SUPPORTED_GROUPS,
ERR_R_INTERNAL_ERROR);
return 0;
}
}
return 1;
}
int tls_parse_stoc_key_share(SSL *s, PACKET *pkt, int *al)
{
unsigned int group_id;
PACKET encoded_pt;
EVP_PKEY *ckey = s->s3->tmp.pkey, *skey = NULL;
/* Sanity check */
if (ckey == NULL) {
*al = SSL_AD_INTERNAL_ERROR;
SSLerr(SSL_F_TLS_PARSE_STOC_KEY_SHARE, ERR_R_INTERNAL_ERROR);
return 0;
}
if (!PACKET_get_net_2(pkt, &group_id)) {
*al = SSL_AD_HANDSHAKE_FAILURE;
SSLerr(SSL_F_TLS_PARSE_STOC_KEY_SHARE, SSL_R_LENGTH_MISMATCH);
return 0;
}
if (group_id != s->s3->group_id) {
/*
* This isn't for the group that we sent in the original
* key_share!
*/
*al = SSL_AD_HANDSHAKE_FAILURE;
SSLerr(SSL_F_TLS_PARSE_STOC_KEY_SHARE, SSL_R_BAD_KEY_SHARE);
return 0;
}
if (!PACKET_as_length_prefixed_2(pkt, &encoded_pt)
|| PACKET_remaining(&encoded_pt) == 0) {
*al = SSL_AD_DECODE_ERROR;
SSLerr(SSL_F_TLS_PARSE_STOC_KEY_SHARE, SSL_R_LENGTH_MISMATCH);
return 0;
}
skey = ssl_generate_pkey(ckey);
if (skey == NULL) {
*al = SSL_AD_INTERNAL_ERROR;
SSLerr(SSL_F_TLS_PARSE_STOC_KEY_SHARE, ERR_R_MALLOC_FAILURE);
return 0;
}
if (!EVP_PKEY_set1_tls_encodedpoint(skey, PACKET_data(&encoded_pt),
PACKET_remaining(&encoded_pt))) {
*al = SSL_AD_DECODE_ERROR;
SSLerr(SSL_F_TLS_PARSE_STOC_KEY_SHARE, SSL_R_BAD_ECPOINT);
return 0;
}
if (ssl_derive(s, ckey, skey, 1) == 0) {
*al = SSL_AD_INTERNAL_ERROR;
SSLerr(SSL_F_TLS_PARSE_STOC_KEY_SHARE, ERR_R_INTERNAL_ERROR);
EVP_PKEY_free(skey);
return 0;
}
EVP_PKEY_free(skey);
return 1;
}
static int test_PACKET_as_length_prefixed_2()
{
unsigned char buf[1024];
const size_t len = 516; /* 0x0204 */
unsigned int i;
PACKET pkt, exact_pkt, subpkt = {0};
for (i = 1; i <= 1024; i++)
buf[i-1] = (i * 2) & 0xff;
if (!TEST_true(PACKET_buf_init(&pkt, buf, 1024))
|| !TEST_true(PACKET_buf_init(&exact_pkt, buf, len + 2))
|| !TEST_false(PACKET_as_length_prefixed_2(&pkt, &subpkt))
|| !TEST_size_t_eq(PACKET_remaining(&pkt), 1024)
|| !TEST_true(PACKET_as_length_prefixed_2(&exact_pkt, &subpkt))
|| !TEST_size_t_eq(PACKET_remaining(&exact_pkt), 0)
|| !TEST_size_t_eq(PACKET_remaining(&subpkt), len))
return 0;
return 1;
}
static int get_sni_from_client_hello(BIO *bio, char **sni)
{
long len;
unsigned char *data;
PACKET pkt = {0}, pkt2 = {0}, pkt3 = {0}, pkt4 = {0}, pkt5 = {0};
unsigned int servname_type = 0, type = 0;
int ret = 0;
len = BIO_get_mem_data(bio, (char **)&data);
if (!TEST_true(PACKET_buf_init(&pkt, data, len))
/* Skip the record header */
|| !PACKET_forward(&pkt, SSL3_RT_HEADER_LENGTH)
/* Skip the handshake message header */
|| !TEST_true(PACKET_forward(&pkt, SSL3_HM_HEADER_LENGTH))
/* Skip client version and random */
|| !TEST_true(PACKET_forward(&pkt, CLIENT_VERSION_LEN
+ SSL3_RANDOM_SIZE))
/* Skip session id */
|| !TEST_true(PACKET_get_length_prefixed_1(&pkt, &pkt2))
/* Skip ciphers */
|| !TEST_true(PACKET_get_length_prefixed_2(&pkt, &pkt2))
/* Skip compression */
|| !TEST_true(PACKET_get_length_prefixed_1(&pkt, &pkt2))
/* Extensions len */
|| !TEST_true(PACKET_as_length_prefixed_2(&pkt, &pkt2)))
goto end;
/* Loop through all extensions for SNI */
while (PACKET_remaining(&pkt2)) {
if (!TEST_true(PACKET_get_net_2(&pkt2, &type))
|| !TEST_true(PACKET_get_length_prefixed_2(&pkt2, &pkt3)))
goto end;
if (type == TLSEXT_TYPE_server_name) {
if (!TEST_true(PACKET_get_length_prefixed_2(&pkt3, &pkt4))
|| !TEST_uint_ne(PACKET_remaining(&pkt4), 0)
|| !TEST_true(PACKET_get_1(&pkt4, &servname_type))
|| !TEST_uint_eq(servname_type, TLSEXT_NAMETYPE_host_name)
|| !TEST_true(PACKET_get_length_prefixed_2(&pkt4, &pkt5))
|| !TEST_uint_le(PACKET_remaining(&pkt5), TLSEXT_MAXLEN_host_name)
|| !TEST_false(PACKET_contains_zero_byte(&pkt5))
|| !TEST_true(PACKET_strndup(&pkt5, sni)))
goto end;
ret = 1;
goto end;
}
}
end:
return ret;
}
int tls_parse_ctos_sig_algs(SSL *s, PACKET *pkt, unsigned int context, X509 *x,
size_t chainidx, int *al)
{
PACKET supported_sig_algs;
if (!PACKET_as_length_prefixed_2(pkt, &supported_sig_algs)
|| PACKET_remaining(&supported_sig_algs) == 0) {
*al = SSL_AD_DECODE_ERROR;
return 0;
}
if (!s->hit && !tls1_save_sigalgs(s, &supported_sig_algs)) {
*al = SSL_AD_DECODE_ERROR;
return 0;
}
return 1;
}
int tls_parse_ctos_sig_algs(SSL *s, PACKET *pkt, int *al)
{
PACKET supported_sig_algs;
if (!PACKET_as_length_prefixed_2(pkt, &supported_sig_algs)
|| (PACKET_remaining(&supported_sig_algs) % 2) != 0
|| PACKET_remaining(&supported_sig_algs) == 0) {
*al = SSL_AD_DECODE_ERROR;
return 0;
}
if (!s->hit && !tls1_save_sigalgs(s, PACKET_data(&supported_sig_algs),
PACKET_remaining(&supported_sig_algs))) {
*al = TLS1_AD_INTERNAL_ERROR;
return 0;
}
return 1;
}
int tls_parse_ctos_sig_algs(SSL *s, PACKET *pkt, unsigned int context, X509 *x,
size_t chainidx)
{
PACKET supported_sig_algs;
if (!PACKET_as_length_prefixed_2(pkt, &supported_sig_algs)
|| PACKET_remaining(&supported_sig_algs) == 0) {
SSLfatal(s, SSL_AD_DECODE_ERROR,
SSL_F_TLS_PARSE_CTOS_SIG_ALGS, SSL_R_BAD_EXTENSION);
return 0;
}
if (!s->hit && !tls1_save_sigalgs(s, &supported_sig_algs)) {
SSLfatal(s, SSL_AD_DECODE_ERROR,
SSL_F_TLS_PARSE_CTOS_SIG_ALGS, SSL_R_BAD_EXTENSION);
return 0;
}
return 1;
}
int tls_parse_ctos_supported_groups(SSL *s, PACKET *pkt, int *al)
{
PACKET supported_groups_list;
/* Each group is 2 bytes and we must have at least 1. */
if (!PACKET_as_length_prefixed_2(pkt, &supported_groups_list)
|| PACKET_remaining(&supported_groups_list) == 0
|| (PACKET_remaining(&supported_groups_list) % 2) != 0) {
*al = SSL_AD_DECODE_ERROR;
return 0;
}
if (!s->hit
&& !PACKET_memdup(&supported_groups_list,
&s->session->tlsext_supportedgroupslist,
&s->session->tlsext_supportedgroupslist_length)) {
*al = SSL_AD_DECODE_ERROR;
return 0;
}
return 1;
}
/*
* Process a key_share extension received in the ClientHello. |pkt| contains
* the raw PACKET data for the extension. Returns 1 on success or 0 on failure.
* If a failure occurs then |*al| is set to an appropriate alert value.
*/
int tls_parse_ctos_key_share(SSL *s, PACKET *pkt, unsigned int context, X509 *x,
size_t chainidx, int *al)
{
#ifndef OPENSSL_NO_TLS1_3
unsigned int group_id;
PACKET key_share_list, encoded_pt;
const unsigned char *clntcurves, *srvrcurves;
size_t clnt_num_curves, srvr_num_curves;
int group_nid, found = 0;
unsigned int curve_flags;
if (s->hit && (s->ext.psk_kex_mode & TLSEXT_KEX_MODE_FLAG_KE_DHE) == 0)
return 1;
/* Sanity check */
if (s->s3->peer_tmp != NULL) {
*al = SSL_AD_INTERNAL_ERROR;
SSLerr(SSL_F_TLS_PARSE_CTOS_KEY_SHARE, ERR_R_INTERNAL_ERROR);
return 0;
}
if (!PACKET_as_length_prefixed_2(pkt, &key_share_list)) {
*al = SSL_AD_DECODE_ERROR;
SSLerr(SSL_F_TLS_PARSE_CTOS_KEY_SHARE, SSL_R_LENGTH_MISMATCH);
return 0;
}
/* Get our list of supported curves */
if (!tls1_get_curvelist(s, 0, &srvrcurves, &srvr_num_curves)) {
*al = SSL_AD_INTERNAL_ERROR;
SSLerr(SSL_F_TLS_PARSE_CTOS_KEY_SHARE, ERR_R_INTERNAL_ERROR);
return 0;
}
/* Get the clients list of supported curves. */
if (!tls1_get_curvelist(s, 1, &clntcurves, &clnt_num_curves)) {
*al = SSL_AD_INTERNAL_ERROR;
SSLerr(SSL_F_TLS_PARSE_CTOS_KEY_SHARE, ERR_R_INTERNAL_ERROR);
return 0;
}
if (clnt_num_curves == 0) {
/*
* This can only happen if the supported_groups extension was not sent,
* because we verify that the length is non-zero when we process that
* extension.
*/
*al = SSL_AD_MISSING_EXTENSION;
SSLerr(SSL_F_TLS_PARSE_CTOS_KEY_SHARE,
SSL_R_MISSING_SUPPORTED_GROUPS_EXTENSION);
return 0;
}
while (PACKET_remaining(&key_share_list) > 0) {
if (!PACKET_get_net_2(&key_share_list, &group_id)
|| !PACKET_get_length_prefixed_2(&key_share_list, &encoded_pt)
|| PACKET_remaining(&encoded_pt) == 0) {
*al = SSL_AD_DECODE_ERROR;
SSLerr(SSL_F_TLS_PARSE_CTOS_KEY_SHARE,
SSL_R_LENGTH_MISMATCH);
return 0;
}
/*
* If we already found a suitable key_share we loop through the
* rest to verify the structure, but don't process them.
*/
if (found)
continue;
/* Check if this share is in supported_groups sent from client */
if (!check_in_list(s, group_id, clntcurves, clnt_num_curves, 0)) {
*al = SSL_AD_ILLEGAL_PARAMETER;
SSLerr(SSL_F_TLS_PARSE_CTOS_KEY_SHARE, SSL_R_BAD_KEY_SHARE);
return 0;
}
/* Check if this share is for a group we can use */
if (!check_in_list(s, group_id, srvrcurves, srvr_num_curves, 1)) {
/* Share not suitable */
continue;
}
group_nid = tls1_ec_curve_id2nid(group_id, &curve_flags);
if (group_nid == 0) {
*al = SSL_AD_INTERNAL_ERROR;
SSLerr(SSL_F_TLS_PARSE_CTOS_KEY_SHARE,
SSL_R_UNABLE_TO_FIND_ECDH_PARAMETERS);
return 0;
}
if ((curve_flags & TLS_CURVE_TYPE) == TLS_CURVE_CUSTOM) {
/* Can happen for some curves, e.g. X25519 */
EVP_PKEY *key = EVP_PKEY_new();
if (key == NULL || !EVP_PKEY_set_type(key, group_nid)) {
*al = SSL_AD_INTERNAL_ERROR;
SSLerr(SSL_F_TLS_PARSE_CTOS_KEY_SHARE, ERR_R_EVP_LIB);
EVP_PKEY_free(key);
return 0;
}
s->s3->peer_tmp = key;
} else {
/* Set up EVP_PKEY with named curve as parameters */
EVP_PKEY_CTX *pctx = EVP_PKEY_CTX_new_id(EVP_PKEY_EC, NULL);
if (pctx == NULL
|| EVP_PKEY_paramgen_init(pctx) <= 0
|| EVP_PKEY_CTX_set_ec_paramgen_curve_nid(pctx,
group_nid) <= 0
|| EVP_PKEY_paramgen(pctx, &s->s3->peer_tmp) <= 0) {
*al = SSL_AD_INTERNAL_ERROR;
SSLerr(SSL_F_TLS_PARSE_CTOS_KEY_SHARE, ERR_R_EVP_LIB);
EVP_PKEY_CTX_free(pctx);
return 0;
}
EVP_PKEY_CTX_free(pctx);
pctx = NULL;
}
s->s3->group_id = group_id;
if (!EVP_PKEY_set1_tls_encodedpoint(s->s3->peer_tmp,
PACKET_data(&encoded_pt),
PACKET_remaining(&encoded_pt))) {
*al = SSL_AD_ILLEGAL_PARAMETER;
SSLerr(SSL_F_TLS_PARSE_CTOS_KEY_SHARE, SSL_R_BAD_ECPOINT);
return 0;
}
found = 1;
}
#endif
return 1;
}
/*
* Process a key_share extension received in the ClientHello. |pkt| contains
* the raw PACKET data for the extension. Returns 1 on success or 0 on failure.
* If a failure occurs then |*al| is set to an appropriate alert value.
*/
int tls_parse_ctos_key_share(SSL *s, PACKET *pkt, int *al)
{
unsigned int group_id;
PACKET key_share_list, encoded_pt;
const unsigned char *clntcurves, *srvrcurves;
size_t clnt_num_curves, srvr_num_curves;
int group_nid, found = 0;
unsigned int curve_flags;
if (s->hit)
return 1;
/* Sanity check */
if (s->s3->peer_tmp != NULL) {
*al = SSL_AD_INTERNAL_ERROR;
SSLerr(SSL_F_TLS_PARSE_CTOS_KEY_SHARE, ERR_R_INTERNAL_ERROR);
return 0;
}
if (!PACKET_as_length_prefixed_2(pkt, &key_share_list)) {
*al = SSL_AD_HANDSHAKE_FAILURE;
SSLerr(SSL_F_TLS_PARSE_CTOS_KEY_SHARE, SSL_R_LENGTH_MISMATCH);
return 0;
}
/* Get our list of supported curves */
if (!tls1_get_curvelist(s, 0, &srvrcurves, &srvr_num_curves)) {
*al = SSL_AD_INTERNAL_ERROR;
SSLerr(SSL_F_TLS_PARSE_CTOS_KEY_SHARE, ERR_R_INTERNAL_ERROR);
return 0;
}
/*
* Get the clients list of supported curves.
* TODO(TLS1.3): We should validate that we actually received
* supported_groups!
*/
if (!tls1_get_curvelist(s, 1, &clntcurves, &clnt_num_curves)) {
*al = SSL_AD_INTERNAL_ERROR;
SSLerr(SSL_F_TLS_PARSE_CTOS_KEY_SHARE, ERR_R_INTERNAL_ERROR);
return 0;
}
while (PACKET_remaining(&key_share_list) > 0) {
if (!PACKET_get_net_2(&key_share_list, &group_id)
|| !PACKET_get_length_prefixed_2(&key_share_list, &encoded_pt)
|| PACKET_remaining(&encoded_pt) == 0) {
*al = SSL_AD_HANDSHAKE_FAILURE;
SSLerr(SSL_F_TLS_PARSE_CTOS_KEY_SHARE,
SSL_R_LENGTH_MISMATCH);
return 0;
}
/*
* If we already found a suitable key_share we loop through the
* rest to verify the structure, but don't process them.
*/
if (found)
continue;
/* Check if this share is in supported_groups sent from client */
if (!check_in_list(s, group_id, clntcurves, clnt_num_curves, 0)) {
*al = SSL_AD_HANDSHAKE_FAILURE;
SSLerr(SSL_F_TLS_PARSE_CTOS_KEY_SHARE, SSL_R_BAD_KEY_SHARE);
return 0;
}
/* Check if this share is for a group we can use */
if (!check_in_list(s, group_id, srvrcurves, srvr_num_curves, 1)) {
/* Share not suitable */
continue;
}
group_nid = tls1_ec_curve_id2nid(group_id, &curve_flags);
if (group_nid == 0) {
*al = SSL_AD_INTERNAL_ERROR;
SSLerr(SSL_F_TLS_PARSE_CTOS_KEY_SHARE,
SSL_R_UNABLE_TO_FIND_ECDH_PARAMETERS);
return 0;
}
if ((curve_flags & TLS_CURVE_TYPE) == TLS_CURVE_CUSTOM) {
/* Can happen for some curves, e.g. X25519 */
EVP_PKEY *key = EVP_PKEY_new();
if (key == NULL || !EVP_PKEY_set_type(key, group_nid)) {
*al = SSL_AD_INTERNAL_ERROR;
SSLerr(SSL_F_TLS_PARSE_CTOS_KEY_SHARE, ERR_R_EVP_LIB);
EVP_PKEY_free(key);
return 0;
}
s->s3->peer_tmp = key;
} else {
/* Set up EVP_PKEY with named curve as parameters */
EVP_PKEY_CTX *pctx = EVP_PKEY_CTX_new_id(EVP_PKEY_EC, NULL);
if (pctx == NULL
|| EVP_PKEY_paramgen_init(pctx) <= 0
|| EVP_PKEY_CTX_set_ec_paramgen_curve_nid(pctx,
group_nid) <= 0
|| EVP_PKEY_paramgen(pctx, &s->s3->peer_tmp) <= 0) {
*al = SSL_AD_INTERNAL_ERROR;
SSLerr(SSL_F_TLS_PARSE_CTOS_KEY_SHARE, ERR_R_EVP_LIB);
EVP_PKEY_CTX_free(pctx);
return 0;
}
EVP_PKEY_CTX_free(pctx);
pctx = NULL;
}
s->s3->group_id = group_id;
if (!EVP_PKEY_set1_tls_encodedpoint(s->s3->peer_tmp,
PACKET_data(&encoded_pt),
PACKET_remaining(&encoded_pt))) {
*al = SSL_AD_DECODE_ERROR;
SSLerr(SSL_F_TLS_PARSE_CTOS_KEY_SHARE, SSL_R_BAD_ECPOINT);
return 0;
}
found = 1;
}
return 1;
}
int tls_parse_ctos_status_request(SSL *s, PACKET *pkt, unsigned int context,
X509 *x, size_t chainidx, int *al)
{
PACKET responder_id_list, exts;
/* Not defined if we get one of these in a client Certificate */
if (x != NULL)
return 1;
if (!PACKET_get_1(pkt, (unsigned int *)&s->ext.status_type)) {
*al = SSL_AD_DECODE_ERROR;
return 0;
}
if (s->ext.status_type != TLSEXT_STATUSTYPE_ocsp) {
/*
* We don't know what to do with any other type so ignore it.
*/
s->ext.status_type = TLSEXT_STATUSTYPE_nothing;
return 1;
}
if (!PACKET_get_length_prefixed_2 (pkt, &responder_id_list)) {
*al = SSL_AD_DECODE_ERROR;
return 0;
}
/*
* We remove any OCSP_RESPIDs from a previous handshake
* to prevent unbounded memory growth - CVE-2016-6304
*/
sk_OCSP_RESPID_pop_free(s->ext.ocsp.ids, OCSP_RESPID_free);
if (PACKET_remaining(&responder_id_list) > 0) {
s->ext.ocsp.ids = sk_OCSP_RESPID_new_null();
if (s->ext.ocsp.ids == NULL) {
*al = SSL_AD_INTERNAL_ERROR;
return 0;
}
} else {
s->ext.ocsp.ids = NULL;
}
while (PACKET_remaining(&responder_id_list) > 0) {
OCSP_RESPID *id;
PACKET responder_id;
const unsigned char *id_data;
if (!PACKET_get_length_prefixed_2(&responder_id_list, &responder_id)
|| PACKET_remaining(&responder_id) == 0) {
*al = SSL_AD_DECODE_ERROR;
return 0;
}
id_data = PACKET_data(&responder_id);
/* TODO(size_t): Convert d2i_* to size_t */
id = d2i_OCSP_RESPID(NULL, &id_data,
(int)PACKET_remaining(&responder_id));
if (id == NULL) {
*al = SSL_AD_DECODE_ERROR;
return 0;
}
if (id_data != PACKET_end(&responder_id)) {
OCSP_RESPID_free(id);
*al = SSL_AD_DECODE_ERROR;
return 0;
}
if (!sk_OCSP_RESPID_push(s->ext.ocsp.ids, id)) {
OCSP_RESPID_free(id);
*al = SSL_AD_INTERNAL_ERROR;
return 0;
}
}
/* Read in request_extensions */
if (!PACKET_as_length_prefixed_2(pkt, &exts)) {
*al = SSL_AD_DECODE_ERROR;
return 0;
}
if (PACKET_remaining(&exts) > 0) {
const unsigned char *ext_data = PACKET_data(&exts);
sk_X509_EXTENSION_pop_free(s->ext.ocsp.exts,
X509_EXTENSION_free);
s->ext.ocsp.exts =
d2i_X509_EXTENSIONS(NULL, &ext_data, (int)PACKET_remaining(&exts));
if (s->ext.ocsp.exts == NULL || ext_data != PACKET_end(&exts)) {
*al = SSL_AD_DECODE_ERROR;
return 0;
}
}
return 1;
}
int tls_parse_stoc_key_share(SSL *s, PACKET *pkt, unsigned int context, X509 *x,
size_t chainidx, int *al)
{
#ifndef OPENSSL_NO_TLS1_3
unsigned int group_id;
PACKET encoded_pt;
EVP_PKEY *ckey = s->s3->tmp.pkey, *skey = NULL;
/* Sanity check */
if (ckey == NULL) {
*al = SSL_AD_INTERNAL_ERROR;
SSLerr(SSL_F_TLS_PARSE_STOC_KEY_SHARE, ERR_R_INTERNAL_ERROR);
return 0;
}
if (!PACKET_get_net_2(pkt, &group_id)) {
*al = SSL_AD_HANDSHAKE_FAILURE;
SSLerr(SSL_F_TLS_PARSE_STOC_KEY_SHARE, SSL_R_LENGTH_MISMATCH);
return 0;
}
if ((context & EXT_TLS1_3_HELLO_RETRY_REQUEST) != 0) {
unsigned const char *pcurves = NULL;
size_t i, num_curves;
if (PACKET_remaining(pkt) != 0) {
*al = SSL_AD_HANDSHAKE_FAILURE;
SSLerr(SSL_F_TLS_PARSE_STOC_KEY_SHARE, SSL_R_LENGTH_MISMATCH);
return 0;
}
/*
* It is an error if the HelloRetryRequest wants a key_share that we
* already sent in the first ClientHello
*/
if (group_id == s->s3->group_id) {
*al = SSL_AD_ILLEGAL_PARAMETER;
SSLerr(SSL_F_TLS_PARSE_STOC_KEY_SHARE, SSL_R_BAD_KEY_SHARE);
return 0;
}
/* Validate the selected group is one we support */
pcurves = s->ext.supportedgroups;
if (!tls1_get_curvelist(s, 0, &pcurves, &num_curves)) {
SSLerr(SSL_F_TLS_PARSE_STOC_KEY_SHARE, ERR_R_INTERNAL_ERROR);
return 0;
}
for (i = 0; i < num_curves; i++, pcurves += 2) {
if (group_id == bytestogroup(pcurves))
break;
}
if (i >= num_curves
|| !tls_curve_allowed(s, pcurves, SSL_SECOP_CURVE_SUPPORTED)) {
*al = SSL_AD_ILLEGAL_PARAMETER;
SSLerr(SSL_F_TLS_PARSE_STOC_KEY_SHARE, SSL_R_BAD_KEY_SHARE);
return 0;
}
s->s3->group_id = group_id;
EVP_PKEY_free(s->s3->tmp.pkey);
s->s3->tmp.pkey = NULL;
return 1;
}
if (group_id != s->s3->group_id) {
/*
* This isn't for the group that we sent in the original
* key_share!
*/
*al = SSL_AD_HANDSHAKE_FAILURE;
SSLerr(SSL_F_TLS_PARSE_STOC_KEY_SHARE, SSL_R_BAD_KEY_SHARE);
return 0;
}
if (!PACKET_as_length_prefixed_2(pkt, &encoded_pt)
|| PACKET_remaining(&encoded_pt) == 0) {
*al = SSL_AD_DECODE_ERROR;
SSLerr(SSL_F_TLS_PARSE_STOC_KEY_SHARE, SSL_R_LENGTH_MISMATCH);
return 0;
}
skey = ssl_generate_pkey(ckey);
if (skey == NULL) {
*al = SSL_AD_INTERNAL_ERROR;
SSLerr(SSL_F_TLS_PARSE_STOC_KEY_SHARE, ERR_R_MALLOC_FAILURE);
return 0;
}
if (!EVP_PKEY_set1_tls_encodedpoint(skey, PACKET_data(&encoded_pt),
PACKET_remaining(&encoded_pt))) {
*al = SSL_AD_DECODE_ERROR;
SSLerr(SSL_F_TLS_PARSE_STOC_KEY_SHARE, SSL_R_BAD_ECPOINT);
EVP_PKEY_free(skey);
return 0;
}
if (ssl_derive(s, ckey, skey, 1) == 0) {
*al = SSL_AD_INTERNAL_ERROR;
SSLerr(SSL_F_TLS_PARSE_STOC_KEY_SHARE, ERR_R_INTERNAL_ERROR);
EVP_PKEY_free(skey);
return 0;
}
EVP_PKEY_free(skey);
#endif
return 1;
}
/*
* Process a key_share extension received in the ClientHello. |pkt| contains
* the raw PACKET data for the extension. Returns 1 on success or 0 on failure.
*/
int tls_parse_ctos_key_share(SSL *s, PACKET *pkt, unsigned int context, X509 *x,
size_t chainidx)
{
#ifndef OPENSSL_NO_TLS1_3
unsigned int group_id;
PACKET key_share_list, encoded_pt;
const uint16_t *clntgroups, *srvrgroups;
size_t clnt_num_groups, srvr_num_groups;
int found = 0;
if (s->hit && (s->ext.psk_kex_mode & TLSEXT_KEX_MODE_FLAG_KE_DHE) == 0)
return 1;
/* Sanity check */
if (s->s3->peer_tmp != NULL) {
SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PARSE_CTOS_KEY_SHARE,
ERR_R_INTERNAL_ERROR);
return 0;
}
if (!PACKET_as_length_prefixed_2(pkt, &key_share_list)) {
SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PARSE_CTOS_KEY_SHARE,
SSL_R_LENGTH_MISMATCH);
return 0;
}
/* Get our list of supported groups */
tls1_get_supported_groups(s, &srvrgroups, &srvr_num_groups);
/* Get the clients list of supported groups. */
tls1_get_peer_groups(s, &clntgroups, &clnt_num_groups);
if (clnt_num_groups == 0) {
/*
* This can only happen if the supported_groups extension was not sent,
* because we verify that the length is non-zero when we process that
* extension.
*/
SSLfatal(s, SSL_AD_MISSING_EXTENSION, SSL_F_TLS_PARSE_CTOS_KEY_SHARE,
SSL_R_MISSING_SUPPORTED_GROUPS_EXTENSION);
return 0;
}
while (PACKET_remaining(&key_share_list) > 0) {
if (!PACKET_get_net_2(&key_share_list, &group_id)
|| !PACKET_get_length_prefixed_2(&key_share_list, &encoded_pt)
|| PACKET_remaining(&encoded_pt) == 0) {
SSLfatal(s, SSL_AD_DECODE_ERROR, SSL_F_TLS_PARSE_CTOS_KEY_SHARE,
SSL_R_LENGTH_MISMATCH);
return 0;
}
/*
* If we already found a suitable key_share we loop through the
* rest to verify the structure, but don't process them.
*/
if (found)
continue;
/* Check if this share is in supported_groups sent from client */
if (!check_in_list(s, group_id, clntgroups, clnt_num_groups, 0)) {
SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER,
SSL_F_TLS_PARSE_CTOS_KEY_SHARE, SSL_R_BAD_KEY_SHARE);
return 0;
}
/* Check if this share is for a group we can use */
if (!check_in_list(s, group_id, srvrgroups, srvr_num_groups, 1)) {
/* Share not suitable */
continue;
}
if ((s->s3->peer_tmp = ssl_generate_param_group(group_id)) == NULL) {
SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_F_TLS_PARSE_CTOS_KEY_SHARE,
SSL_R_UNABLE_TO_FIND_ECDH_PARAMETERS);
return 0;
}
s->s3->group_id = group_id;
if (!EVP_PKEY_set1_tls_encodedpoint(s->s3->peer_tmp,
PACKET_data(&encoded_pt),
PACKET_remaining(&encoded_pt))) {
SSLfatal(s, SSL_AD_ILLEGAL_PARAMETER,
SSL_F_TLS_PARSE_CTOS_KEY_SHARE, SSL_R_BAD_ECPOINT);
return 0;
}
found = 1;
}
#endif
return 1;
}
/*-
* The servername extension is treated as follows:
*
* - Only the hostname type is supported with a maximum length of 255.
* - The servername is rejected if too long or if it contains zeros,
* in which case an fatal alert is generated.
* - The servername field is maintained together with the session cache.
* - When a session is resumed, the servername call back invoked in order
* to allow the application to position itself to the right context.
* - The servername is acknowledged if it is new for a session or when
* it is identical to a previously used for the same session.
* Applications can control the behaviour. They can at any time
* set a 'desirable' servername for a new SSL object. This can be the
* case for example with HTTPS when a Host: header field is received and
* a renegotiation is requested. In this case, a possible servername
* presented in the new client hello is only acknowledged if it matches
* the value of the Host: field.
* - Applications must use SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION
* if they provide for changing an explicit servername context for the
* session, i.e. when the session has been established with a servername
* extension.
* - On session reconnect, the servername extension may be absent.
*/
int tls_parse_ctos_server_name(SSL *s, PACKET *pkt, unsigned int context,
X509 *x, size_t chainidx, int *al)
{
unsigned int servname_type;
PACKET sni, hostname;
if (!PACKET_as_length_prefixed_2(pkt, &sni)
/* ServerNameList must be at least 1 byte long. */
|| PACKET_remaining(&sni) == 0) {
*al = SSL_AD_DECODE_ERROR;
return 0;
}
/*
* Although the intent was for server_name to be extensible, RFC 4366
* was not clear about it; and so OpenSSL among other implementations,
* always and only allows a 'host_name' name types.
* RFC 6066 corrected the mistake but adding new name types
* is nevertheless no longer feasible, so act as if no other
* SNI types can exist, to simplify parsing.
*
* Also note that the RFC permits only one SNI value per type,
* i.e., we can only have a single hostname.
*/
if (!PACKET_get_1(&sni, &servname_type)
|| servname_type != TLSEXT_NAMETYPE_host_name
|| !PACKET_as_length_prefixed_2(&sni, &hostname)) {
*al = SSL_AD_DECODE_ERROR;
return 0;
}
if (!s->hit) {
if (PACKET_remaining(&hostname) > TLSEXT_MAXLEN_host_name) {
*al = TLS1_AD_UNRECOGNIZED_NAME;
return 0;
}
if (PACKET_contains_zero_byte(&hostname)) {
*al = TLS1_AD_UNRECOGNIZED_NAME;
return 0;
}
OPENSSL_free(s->session->ext.hostname);
s->session->ext.hostname = NULL;
if (!PACKET_strndup(&hostname, &s->session->ext.hostname)) {
*al = TLS1_AD_INTERNAL_ERROR;
return 0;
}
s->servername_done = 1;
} else {
/*
* TODO(openssl-team): if the SNI doesn't match, we MUST
* fall back to a full handshake.
*/
s->servername_done = s->session->ext.hostname
&& PACKET_equal(&hostname, s->session->ext.hostname,
strlen(s->session->ext.hostname));
}
return 1;
}
static int test_client_hello(int currtest)
{
SSL_CTX *ctx;
SSL *con = NULL;
BIO *rbio;
BIO *wbio;
long len;
unsigned char *data;
PACKET pkt = {0}, pkt2 = {0}, pkt3 = {0};
char *dummytick = "Hello World!";
unsigned int type = 0;
int testresult = 0;
size_t msglen;
BIO *sessbio = NULL;
SSL_SESSION *sess = NULL;
#ifdef OPENSSL_NO_TLS1_3
if (currtest == TEST_ADD_PADDING_AND_PSK)
return 1;
#endif
/*
* For each test set up an SSL_CTX and SSL and see what ClientHello gets
* produced when we try to connect
*/
ctx = SSL_CTX_new(TLS_method());
if (!TEST_ptr(ctx))
goto end;
switch(currtest) {
case TEST_SET_SESSION_TICK_DATA_VER_NEG:
/* Testing for session tickets <= TLS1.2; not relevant for 1.3 */
if (!TEST_true(SSL_CTX_set_max_proto_version(ctx, TLS1_2_VERSION)))
goto end;
break;
case TEST_ADD_PADDING_AND_PSK:
case TEST_ADD_PADDING:
case TEST_PADDING_NOT_NEEDED:
SSL_CTX_set_options(ctx, SSL_OP_TLSEXT_PADDING);
/*
* Add lots of ciphersuites so that the ClientHello is at least
* F5_WORKAROUND_MIN_MSG_LEN bytes long - meaning padding will be
* needed. Also add some dummy ALPN protocols in case we still don't
* have enough.
*/
if (currtest == TEST_ADD_PADDING
&& (!TEST_true(SSL_CTX_set_cipher_list(ctx, "ALL"))
|| !TEST_false(SSL_CTX_set_alpn_protos(ctx,
(unsigned char *)alpn_prots,
sizeof(alpn_prots) - 1))))
goto end;
break;
default:
goto end;
}
con = SSL_new(ctx);
if (!TEST_ptr(con))
goto end;
if (currtest == TEST_ADD_PADDING_AND_PSK) {
sessbio = BIO_new_file(sessionfile, "r");
if (!TEST_ptr(sessbio)) {
TEST_info("Unable to open session.pem");
goto end;
}
sess = PEM_read_bio_SSL_SESSION(sessbio, NULL, NULL, NULL);
if (!TEST_ptr(sess)) {
TEST_info("Unable to load SSL_SESSION");
goto end;
}
/*
* We reset the creation time so that we don't discard the session as
* too old.
*/
if (!TEST_true(SSL_SESSION_set_time(sess, time(NULL)))
|| !TEST_true(SSL_set_session(con, sess)))
goto end;
}
rbio = BIO_new(BIO_s_mem());
wbio = BIO_new(BIO_s_mem());
if (!TEST_ptr(rbio)|| !TEST_ptr(wbio)) {
BIO_free(rbio);
BIO_free(wbio);
goto end;
}
SSL_set_bio(con, rbio, wbio);
SSL_set_connect_state(con);
if (currtest == TEST_SET_SESSION_TICK_DATA_VER_NEG) {
if (!TEST_true(SSL_set_session_ticket_ext(con, dummytick,
strlen(dummytick))))
goto end;
}
if (!TEST_int_le(SSL_connect(con), 0)) {
/* This shouldn't succeed because we don't have a server! */
goto end;
}
len = BIO_get_mem_data(wbio, (char **)&data);
if (!TEST_true(PACKET_buf_init(&pkt, data, len))
/* Skip the record header */
|| !PACKET_forward(&pkt, SSL3_RT_HEADER_LENGTH))
goto end;
msglen = PACKET_remaining(&pkt);
/* Skip the handshake message header */
if (!TEST_true(PACKET_forward(&pkt, SSL3_HM_HEADER_LENGTH))
/* Skip client version and random */
|| !TEST_true(PACKET_forward(&pkt, CLIENT_VERSION_LEN
+ SSL3_RANDOM_SIZE))
/* Skip session id */
|| !TEST_true(PACKET_get_length_prefixed_1(&pkt, &pkt2))
/* Skip ciphers */
|| !TEST_true(PACKET_get_length_prefixed_2(&pkt, &pkt2))
/* Skip compression */
|| !TEST_true(PACKET_get_length_prefixed_1(&pkt, &pkt2))
/* Extensions len */
|| !TEST_true(PACKET_as_length_prefixed_2(&pkt, &pkt2)))
goto end;
/* Loop through all extensions */
while (PACKET_remaining(&pkt2)) {
if (!TEST_true(PACKET_get_net_2(&pkt2, &type))
|| !TEST_true(PACKET_get_length_prefixed_2(&pkt2, &pkt3)))
goto end;
if (type == TLSEXT_TYPE_session_ticket) {
if (currtest == TEST_SET_SESSION_TICK_DATA_VER_NEG) {
if (TEST_true(PACKET_equal(&pkt3, dummytick,
strlen(dummytick)))) {
/* Ticket data is as we expected */
testresult = 1;
}
goto end;
}
}
if (type == TLSEXT_TYPE_padding) {
if (!TEST_false(currtest == TEST_PADDING_NOT_NEEDED))
goto end;
else if (TEST_true(currtest == TEST_ADD_PADDING
|| currtest == TEST_ADD_PADDING_AND_PSK))
testresult = TEST_true(msglen == F5_WORKAROUND_MAX_MSG_LEN);
}
}
if (currtest == TEST_PADDING_NOT_NEEDED)
testresult = 1;
end:
SSL_free(con);
SSL_CTX_free(ctx);
SSL_SESSION_free(sess);
BIO_free(sessbio);
return testresult;
}
