Refactor ClientHello processing so that extensions get parsed earlier

Reviewed-by: Kurt Roeckx <kurt@openssl.org>
Reviewed-by: Rich Salz <rsalz@openssl.org>
This commit is contained in:
Matt Caswell 2016-10-22 17:24:37 +01:00
parent e3fb4d3d52
commit 1ab3836b3b
8 changed files with 446 additions and 295 deletions

View File

@ -2256,6 +2256,7 @@ int ERR_load_SSL_strings(void);
# define SSL_F_TLS_CONSTRUCT_SERVER_KEY_EXCHANGE 377
# define SSL_F_TLS_GET_MESSAGE_BODY 351
# define SSL_F_TLS_GET_MESSAGE_HEADER 387
# define SSL_F_TLS_PARSE_RAW_EXTENSIONS 432
# define SSL_F_TLS_POST_PROCESS_CLIENT_HELLO 378
# define SSL_F_TLS_POST_PROCESS_CLIENT_KEY_EXCHANGE 384
# define SSL_F_TLS_PREPARE_CLIENT_CERTIFICATE 360

View File

@ -279,6 +279,7 @@ static ERR_STRING_DATA SSL_str_functs[] = {
"tls_construct_server_key_exchange"},
{ERR_FUNC(SSL_F_TLS_GET_MESSAGE_BODY), "tls_get_message_body"},
{ERR_FUNC(SSL_F_TLS_GET_MESSAGE_HEADER), "tls_get_message_header"},
{ERR_FUNC(SSL_F_TLS_PARSE_RAW_EXTENSIONS), "tls_parse_raw_extensions"},
{ERR_FUNC(SSL_F_TLS_POST_PROCESS_CLIENT_HELLO),
"tls_post_process_client_hello"},
{ERR_FUNC(SSL_F_TLS_POST_PROCESS_CLIENT_KEY_EXCHANGE),

View File

@ -1624,6 +1624,29 @@ typedef struct ssl3_comp_st {
} SSL3_COMP;
# endif
typedef struct {
unsigned int type;
PACKET data;
} RAW_EXTENSION;
#define MAX_COMPRESSIONS_SIZE 255
typedef struct {
unsigned int isv2;
unsigned int version;
unsigned char random[SSL3_RANDOM_SIZE];
size_t session_id_len;
unsigned char session_id[SSL_MAX_SSL_SESSION_ID_LENGTH];
size_t dtls_cookie_len;
unsigned char dtls_cookie[DTLS1_COOKIE_LENGTH];
PACKET ciphersuites;
size_t compressions_len;
unsigned char compressions[MAX_COMPRESSIONS_SIZE];
PACKET extensions;
size_t num_extensions;
RAW_EXTENSION *pre_proc_exts;
} CLIENTHELLO_MSG;
extern SSL3_ENC_METHOD ssl3_undef_enc_method;
__owur const SSL_METHOD *ssl_bad_method(int ver);
@ -1797,8 +1820,7 @@ __owur CERT *ssl_cert_dup(CERT *cert);
void ssl_cert_clear_certs(CERT *c);
void ssl_cert_free(CERT *c);
__owur int ssl_get_new_session(SSL *s, int session);
__owur int ssl_get_prev_session(SSL *s, const PACKET *ext,
const PACKET *session_id);
__owur int ssl_get_prev_session(SSL *s, CLIENTHELLO_MSG *hello);
__owur SSL_SESSION *ssl_session_dup(SSL_SESSION *src, int ticket);
__owur int ssl_cipher_id_cmp(const SSL_CIPHER *a, const SSL_CIPHER *b);
DECLARE_OBJ_BSEARCH_GLOBAL_CMP_FN(SSL_CIPHER, SSL_CIPHER, ssl_cipher_id);
@ -1919,7 +1941,7 @@ __owur int ssl_version_supported(const SSL *s, int version);
__owur int ssl_set_client_hello_version(SSL *s);
__owur int ssl_check_version_downgrade(SSL *s);
__owur int ssl_set_version_bound(int method_version, int version, int *bound);
__owur int ssl_choose_server_version(SSL *s);
__owur int ssl_choose_server_version(SSL *s, CLIENTHELLO_MSG *hello);
__owur int ssl_choose_client_version(SSL *s, int version);
int ssl_get_client_min_max_version(const SSL *s, int *min_version,
int *max_version);
@ -2020,7 +2042,7 @@ __owur int tls1_shared_list(SSL *s,
const unsigned char *l2, size_t l2len, int nmatch);
__owur int ssl_add_clienthello_tlsext(SSL *s, WPACKET *pkt, int *al);
__owur int ssl_add_serverhello_tlsext(SSL *s, WPACKET *pkt, int *al);
__owur int ssl_parse_clienthello_tlsext(SSL *s, PACKET *pkt);
__owur int ssl_parse_clienthello_tlsext(SSL *s, CLIENTHELLO_MSG *hello);
void ssl_set_default_md(SSL *s);
__owur int tls1_set_server_sigalgs(SSL *s);
__owur int ssl_check_clienthello_tlsext_late(SSL *s, int *al);
@ -2034,9 +2056,9 @@ __owur int dtls1_process_heartbeat(SSL *s, unsigned char *p,
size_t length);
# endif
__owur int tls_check_serverhello_tlsext_early(SSL *s, const PACKET *ext,
const PACKET *session_id,
SSL_SESSION **ret);
__owur int tls_get_ticket_from_client(SSL *s, CLIENTHELLO_MSG *hello,
SSL_SESSION **ret);
__owur int tls_check_client_ems_support(SSL *s, CLIENTHELLO_MSG *hello);
__owur int tls12_get_sigandhash(WPACKET *pkt, const EVP_PKEY *pk,
const EVP_MD *md);

View File

@ -445,7 +445,7 @@ int ssl_get_new_session(SSL *s, int session)
* - Both for new and resumed sessions, s->tlsext_ticket_expected is set to 1
* if the server should issue a new session ticket (to 0 otherwise).
*/
int ssl_get_prev_session(SSL *s, const PACKET *ext, const PACKET *session_id)
int ssl_get_prev_session(SSL *s, CLIENTHELLO_MSG *hello)
{
/* This is used only by servers. */
@ -454,11 +454,11 @@ int ssl_get_prev_session(SSL *s, const PACKET *ext, const PACKET *session_id)
int try_session_cache = 1;
int r;
if (PACKET_remaining(session_id) == 0)
if (hello->session_id_len == 0)
try_session_cache = 0;
/* sets s->tlsext_ticket_expected and extended master secret flag */
r = tls_check_serverhello_tlsext_early(s, ext, session_id, &ret);
/* sets s->tlsext_ticket_expected */
r = tls_get_ticket_from_client(s, hello, &ret);
switch (r) {
case -1: /* Error during processing */
fatal = 1;
@ -479,14 +479,12 @@ int ssl_get_prev_session(SSL *s, const PACKET *ext, const PACKET *session_id)
!(s->session_ctx->session_cache_mode &
SSL_SESS_CACHE_NO_INTERNAL_LOOKUP)) {
SSL_SESSION data;
size_t local_len;
data.ssl_version = s->version;
memset(data.session_id, 0, sizeof(data.session_id));
if (!PACKET_copy_all(session_id, data.session_id,
sizeof(data.session_id), &local_len)) {
goto err;
}
data.session_id_length = local_len;
memcpy(data.session_id, hello->session_id, hello->session_id_len);
data.session_id_length = hello->session_id_len;
CRYPTO_THREAD_read_lock(s->session_ctx->lock);
ret = lh_SSL_SESSION_retrieve(s->session_ctx->sessions, &data);
if (ret != NULL) {
@ -501,8 +499,9 @@ int ssl_get_prev_session(SSL *s, const PACKET *ext, const PACKET *session_id)
if (try_session_cache &&
ret == NULL && s->session_ctx->get_session_cb != NULL) {
int copy = 1;
ret = s->session_ctx->get_session_cb(s, PACKET_data(session_id),
(int)PACKET_remaining(session_id),
ret = s->session_ctx->get_session_cb(s, hello->session_id,
hello->session_id_len,
&copy);
if (ret != NULL) {

View File

@ -152,6 +152,94 @@ static void ssl3_take_mac(SSL *s)
}
#endif
static int compare_extensions(const void *p1, const void *p2)
{
const RAW_EXTENSION *e1 = (const RAW_EXTENSION *)p1;
const RAW_EXTENSION *e2 = (const RAW_EXTENSION *)p2;
if (e1->type < e2->type)
return -1;
else if (e1->type > e2->type)
return 1;
else
return 0;
}
/*
* Gather a list of all the extensions. We don't actually process the content
* of the extensions yet, except to check their types.
*
* Per http://tools.ietf.org/html/rfc5246#section-7.4.1.4, there may not be
* more than one extension of the same type in a ClientHello or ServerHello.
* This function returns 1 if all extensions are unique and we have parsed their
* types, and 0 if the extensions contain duplicates, could not be successfully
* parsed, or an internal error occurred.
*/
int tls_parse_raw_extensions(PACKET *packet, RAW_EXTENSION **res,
size_t *numfound, int *ad)
{
PACKET extensions = *packet;
size_t num_extensions = 0, i = 0;
RAW_EXTENSION *raw_extensions = NULL;
/* First pass: count the extensions. */
while (PACKET_remaining(&extensions) > 0) {
unsigned int type;
PACKET extension;
if (!PACKET_get_net_2(&extensions, &type) ||
!PACKET_get_length_prefixed_2(&extensions, &extension)) {
*ad = SSL_AD_DECODE_ERROR;
goto done;
}
num_extensions++;
}
if (num_extensions > 0) {
raw_extensions = OPENSSL_malloc(sizeof(RAW_EXTENSION) * num_extensions);
if (raw_extensions == NULL) {
*ad = SSL_AD_INTERNAL_ERROR;
SSLerr(SSL_F_TLS_PARSE_RAW_EXTENSIONS, ERR_R_MALLOC_FAILURE);
goto done;
}
/* Second pass: gather the extension types. */
for (i = 0; i < num_extensions; i++) {
if (!PACKET_get_net_2(packet, &raw_extensions[i].type) ||
!PACKET_get_length_prefixed_2(packet,
&raw_extensions[i].data)) {
/* This should not happen. */
*ad = SSL_AD_INTERNAL_ERROR;
SSLerr(SSL_F_TLS_PARSE_RAW_EXTENSIONS, ERR_R_INTERNAL_ERROR);
goto done;
}
}
if (PACKET_remaining(packet) != 0) {
*ad = SSL_AD_DECODE_ERROR;
SSLerr(SSL_F_TLS_PARSE_RAW_EXTENSIONS, SSL_R_LENGTH_MISMATCH);
goto done;
}
/* Sort the extensions and make sure there are no duplicates. */
qsort(raw_extensions, num_extensions, sizeof(RAW_EXTENSION),
compare_extensions);
for (i = 1; i < num_extensions; i++) {
if (raw_extensions[i - 1].type == raw_extensions[i].type) {
*ad = SSL_AD_DECODE_ERROR;
goto done;
}
}
}
*res = raw_extensions;
*numfound = num_extensions;
return 1;
done:
OPENSSL_free(raw_extensions);
return 0;
}
MSG_PROCESS_RETURN tls_process_change_cipher_spec(SSL *s, PACKET *pkt)
{
int al;
@ -875,7 +963,7 @@ int ssl_set_version_bound(int method_version, int version, int *bound)
*
* Returns 0 on success or an SSL error reason number on failure.
*/
int ssl_choose_server_version(SSL *s)
int ssl_choose_server_version(SSL *s, CLIENTHELLO_MSG *hello)
{
/*-
* With version-flexible methods we have an initial state with:
@ -887,11 +975,13 @@ int ssl_choose_server_version(SSL *s)
* handle version.
*/
int server_version = s->method->version;
int client_version = s->client_version;
int client_version = hello->version;
const version_info *vent;
const version_info *table;
int disabled = 0;
s->client_version = client_version;
switch (server_version) {
default:
if (version_cmp(s, client_version, s->version) < 0)

View File

@ -86,6 +86,9 @@ __owur int tls_construct_finished(SSL *s, WPACKET *pkt);
__owur WORK_STATE tls_finish_handshake(SSL *s, WORK_STATE wst);
__owur WORK_STATE dtls_wait_for_dry(SSL *s);
int tls_parse_raw_extensions(PACKET *packet, RAW_EXTENSION **res,
size_t *numfound, int *ad);
/* some client-only functions */
__owur int tls_construct_client_hello(SSL *s, WPACKET *pkt);
__owur MSG_PROCESS_RETURN tls_process_server_hello(SSL *s, PACKET *pkt);

View File

@ -889,7 +889,7 @@ MSG_PROCESS_RETURN tls_process_client_hello(SSL *s, PACKET *pkt)
{
int i, al = SSL_AD_INTERNAL_ERROR;
unsigned int j;
size_t loop, complen = 0;
size_t loop;
unsigned long id;
const SSL_CIPHER *c;
#ifndef OPENSSL_NO_COMP
@ -898,16 +898,20 @@ MSG_PROCESS_RETURN tls_process_client_hello(SSL *s, PACKET *pkt)
STACK_OF(SSL_CIPHER) *ciphers = NULL;
int protverr;
/* |cookie| will only be initialized for DTLS. */
PACKET session_id, cipher_suites, compression, extensions, cookie;
int is_v2_record;
PACKET session_id, compression, extensions, cookie;
static const unsigned char null_compression = 0;
CLIENTHELLO_MSG clienthello;
is_v2_record = RECORD_LAYER_is_sslv2_record(&s->rlayer);
/*
* First step is to parse the raw ClientHello data into the CLIENTHELLO_MSG
* structure.
*/
clienthello.isv2 = RECORD_LAYER_is_sslv2_record(&s->rlayer);
PACKET_null_init(&cookie);
/* First lets get s->client_version set correctly */
if (is_v2_record) {
unsigned int version;
if (clienthello.isv2) {
unsigned int mt;
/*-
* An SSLv3/TLSv1 backwards-compatible CLIENT-HELLO in an SSLv2
@ -934,73 +938,25 @@ MSG_PROCESS_RETURN tls_process_client_hello(SSL *s, PACKET *pkt)
SSLerr(SSL_F_TLS_PROCESS_CLIENT_HELLO, ERR_R_INTERNAL_ERROR);
goto err;
}
if (!PACKET_get_net_2(pkt, &version)) {
/* No protocol version supplied! */
SSLerr(SSL_F_TLS_PROCESS_CLIENT_HELLO, SSL_R_UNKNOWN_PROTOCOL);
goto err;
}
if (version == 0x0002) {
/* This is real SSLv2. We don't support it. */
SSLerr(SSL_F_TLS_PROCESS_CLIENT_HELLO, SSL_R_UNKNOWN_PROTOCOL);
goto err;
} else if ((version & 0xff00) == (SSL3_VERSION_MAJOR << 8)) {
/* SSLv3/TLS */
s->client_version = version;
} else {
/* No idea what protocol this is */
SSLerr(SSL_F_TLS_PROCESS_CLIENT_HELLO, SSL_R_UNKNOWN_PROTOCOL);
goto err;
}
} else {
/*
* use version from inside client hello, not from record header (may
* differ: see RFC 2246, Appendix E, second paragraph)
*/
if (!PACKET_get_net_2(pkt, (unsigned int *)&s->client_version)) {
al = SSL_AD_DECODE_ERROR;
SSLerr(SSL_F_TLS_PROCESS_CLIENT_HELLO, SSL_R_LENGTH_TOO_SHORT);
goto f_err;
}
}
/*
* Do SSL/TLS version negotiation if applicable. For DTLS we just check
* versions are potentially compatible. Version negotiation comes later.
*/
if (!SSL_IS_DTLS(s)) {
protverr = ssl_choose_server_version(s);
} else if (s->method->version != DTLS_ANY_VERSION &&
DTLS_VERSION_LT(s->client_version, s->version)) {
protverr = SSL_R_VERSION_TOO_LOW;
} else {
protverr = 0;
}
if (protverr) {
SSLerr(SSL_F_TLS_PROCESS_CLIENT_HELLO, protverr);
if ((!s->enc_write_ctx && !s->write_hash)) {
/*
* similar to ssl3_get_record, send alert using remote version
* number
*/
s->version = s->client_version;
}
al = SSL_AD_PROTOCOL_VERSION;
goto f_err;
if (!PACKET_get_net_2(pkt, &clienthello.version)) {
al = SSL_AD_DECODE_ERROR;
SSLerr(SSL_F_TLS_PROCESS_CLIENT_HELLO, SSL_R_LENGTH_TOO_SHORT);
goto err;
}
/* Parse the message and load client random. */
if (is_v2_record) {
if (clienthello.isv2) {
/*
* Handle an SSLv2 backwards compatible ClientHello
* Note, this is only for SSLv3+ using the backward compatible format.
* Real SSLv2 is not supported, and is rejected above.
*/
unsigned int cipher_len, session_id_len, challenge_len;
unsigned int ciphersuite_len, session_id_len, challenge_len;
PACKET challenge;
if (!PACKET_get_net_2(pkt, &cipher_len)
if (!PACKET_get_net_2(pkt, &ciphersuite_len)
|| !PACKET_get_net_2(pkt, &session_id_len)
|| !PACKET_get_net_2(pkt, &challenge_len)) {
SSLerr(SSL_F_TLS_PROCESS_CLIENT_HELLO,
@ -1008,6 +964,7 @@ MSG_PROCESS_RETURN tls_process_client_hello(SSL *s, PACKET *pkt)
al = SSL_AD_DECODE_ERROR;
goto f_err;
}
clienthello.session_id_len = session_id_len;
if (session_id_len > SSL_MAX_SSL_SESSION_ID_LENGTH) {
al = SSL_AD_DECODE_ERROR;
@ -1015,8 +972,10 @@ MSG_PROCESS_RETURN tls_process_client_hello(SSL *s, PACKET *pkt)
goto f_err;
}
if (!PACKET_get_sub_packet(pkt, &cipher_suites, cipher_len)
|| !PACKET_get_sub_packet(pkt, &session_id, session_id_len)
if (!PACKET_get_sub_packet(pkt, &clienthello.ciphersuites,
ciphersuite_len)
|| !PACKET_get_sub_packet(pkt, &session_id,
clienthello.session_id_len)
|| !PACKET_get_sub_packet(pkt, &challenge, challenge_len)
/* No extensions. */
|| PACKET_remaining(pkt) != 0) {
@ -1029,9 +988,9 @@ MSG_PROCESS_RETURN tls_process_client_hello(SSL *s, PACKET *pkt)
/* Load the client random and compression list. */
challenge_len = challenge_len > SSL3_RANDOM_SIZE ? SSL3_RANDOM_SIZE :
challenge_len;
memset(s->s3->client_random, 0, SSL3_RANDOM_SIZE);
memset(clienthello.random, 0, SSL3_RANDOM_SIZE);
if (!PACKET_copy_bytes(&challenge,
s->s3->client_random + SSL3_RANDOM_SIZE -
clienthello.random + SSL3_RANDOM_SIZE -
challenge_len, challenge_len)
/* Advertise only null compression. */
|| !PACKET_buf_init(&compression, &null_compression, 1)) {
@ -1040,55 +999,136 @@ MSG_PROCESS_RETURN tls_process_client_hello(SSL *s, PACKET *pkt)
goto f_err;
}
PACKET_null_init(&extensions);
PACKET_null_init(&clienthello.extensions);
} else {
/* Regular ClientHello. */
if (!PACKET_copy_bytes(pkt, s->s3->client_random, SSL3_RANDOM_SIZE)
if (!PACKET_copy_bytes(pkt, clienthello.random, SSL3_RANDOM_SIZE)
|| !PACKET_get_length_prefixed_1(pkt, &session_id)) {
al = SSL_AD_DECODE_ERROR;
SSLerr(SSL_F_TLS_PROCESS_CLIENT_HELLO, SSL_R_LENGTH_MISMATCH);
goto f_err;
}
if (PACKET_remaining(&session_id) > SSL_MAX_SSL_SESSION_ID_LENGTH) {
al = SSL_AD_DECODE_ERROR;
SSLerr(SSL_F_TLS_PROCESS_CLIENT_HELLO, SSL_R_LENGTH_MISMATCH);
goto f_err;
}
if (SSL_IS_DTLS(s)) {
if (!PACKET_get_length_prefixed_1(pkt, &cookie)) {
al = SSL_AD_DECODE_ERROR;
SSLerr(SSL_F_TLS_PROCESS_CLIENT_HELLO, SSL_R_LENGTH_MISMATCH);
goto f_err;
}
if (!PACKET_copy_all(&cookie, clienthello.dtls_cookie,
DTLS1_COOKIE_LENGTH,
&clienthello.dtls_cookie_len)) {
al = SSL_AD_DECODE_ERROR;
SSLerr(SSL_F_TLS_PROCESS_CLIENT_HELLO, SSL_R_LENGTH_MISMATCH);
goto f_err;
}
/*
* If we require cookies and this ClientHello doesn't contain one,
* just return since we do not want to allocate any memory yet.
* So check cookie length...
*/
if (SSL_get_options(s) & SSL_OP_COOKIE_EXCHANGE) {
if (PACKET_remaining(&cookie) == 0)
if (clienthello.dtls_cookie_len == 0)
return 1;
}
}
if (!PACKET_get_length_prefixed_2(pkt, &cipher_suites)
|| !PACKET_get_length_prefixed_1(pkt, &compression)) {
if (!PACKET_get_length_prefixed_2(pkt, &clienthello.ciphersuites)) {
al = SSL_AD_DECODE_ERROR;
SSLerr(SSL_F_TLS_PROCESS_CLIENT_HELLO, SSL_R_LENGTH_MISMATCH);
goto f_err;
}
if (!PACKET_get_length_prefixed_1(pkt, &compression)
|| !PACKET_copy_all(&compression, clienthello.compressions,
MAX_COMPRESSIONS_SIZE,
&clienthello.compressions_len)) {
al = SSL_AD_DECODE_ERROR;
SSLerr(SSL_F_TLS_PROCESS_CLIENT_HELLO, SSL_R_LENGTH_MISMATCH);
goto f_err;
}
/* Could be empty. */
extensions = *pkt;
if (PACKET_remaining(pkt) == 0) {
PACKET_null_init(&clienthello.extensions);
} else {
if (!PACKET_get_length_prefixed_2(pkt, &clienthello.extensions)) {
al = SSL_AD_DECODE_ERROR;
SSLerr(SSL_F_TLS_PROCESS_CLIENT_HELLO, SSL_R_LENGTH_MISMATCH);
goto f_err;
}
}
}
if (!PACKET_copy_all(&session_id, clienthello.session_id,
SSL_MAX_SSL_SESSION_ID_LENGTH,
&clienthello.session_id_len)) {
al = SSL_AD_DECODE_ERROR;
SSLerr(SSL_F_TLS_PROCESS_CLIENT_HELLO, SSL_R_LENGTH_MISMATCH);
goto f_err;
}
/* We preserve the raw extensions PACKET for later use */
extensions = clienthello.extensions;
if (!tls_parse_raw_extensions(&extensions, &clienthello.pre_proc_exts,
&clienthello.num_extensions, &al)) {
/* SSLerr already been called */
goto f_err;
}
/* Finished parsing the ClientHello, now we can start processing it */
/* Set up the client_random */
memcpy(s->s3->client_random, clienthello.random, SSL3_RANDOM_SIZE);
/* Choose the version */
if (clienthello.isv2) {
if (clienthello.version == 0x0002) {
/* This is real SSLv2. We don't support it. */
SSLerr(SSL_F_TLS_PROCESS_CLIENT_HELLO, SSL_R_UNKNOWN_PROTOCOL);
goto err;
} else if ((clienthello.version & 0xff00) == (SSL3_VERSION_MAJOR << 8)) {
/* SSLv3/TLS */
s->client_version = clienthello.version;
} else {
/* No idea what protocol this is */
SSLerr(SSL_F_TLS_PROCESS_CLIENT_HELLO, SSL_R_UNKNOWN_PROTOCOL);
goto err;
}
}
/*
* Do SSL/TLS version negotiation if applicable. For DTLS we just check
* versions are potentially compatible. Version negotiation comes later.
*/
if (!SSL_IS_DTLS(s)) {
protverr = ssl_choose_server_version(s, &clienthello);
} else if (s->method->version != DTLS_ANY_VERSION &&
DTLS_VERSION_LT((int)clienthello.version, s->version)) {
protverr = SSL_R_VERSION_TOO_LOW;
} else {
protverr = 0;
}
if (protverr) {
SSLerr(SSL_F_TLS_PROCESS_CLIENT_HELLO, protverr);
if ((!s->enc_write_ctx && !s->write_hash)) {
/*
* similar to ssl3_get_record, send alert using remote version
* number
*/
s->version = s->client_version = clienthello.version;
}
al = SSL_AD_PROTOCOL_VERSION;
goto f_err;
}
if (SSL_IS_DTLS(s)) {
/* Empty cookie was already handled above by returning early. */
if (SSL_get_options(s) & SSL_OP_COOKIE_EXCHANGE) {
if (s->ctx->app_verify_cookie_cb != NULL) {
if (s->ctx->app_verify_cookie_cb(s, PACKET_data(&cookie),
(unsigned int)PACKET_remaining(&cookie)) == 0) {
if (s->ctx->app_verify_cookie_cb(s, clienthello.dtls_cookie,
clienthello.dtls_cookie_len) == 0) {
al = SSL_AD_HANDSHAKE_FAILURE;
SSLerr(SSL_F_TLS_PROCESS_CLIENT_HELLO,
SSL_R_COOKIE_MISMATCH);
@ -1096,7 +1136,9 @@ MSG_PROCESS_RETURN tls_process_client_hello(SSL *s, PACKET *pkt)
/* else cookie verification succeeded */
}
/* default verification */
} else if (!PACKET_equal(&cookie, s->d1->cookie, s->d1->cookie_len)) {
} else if (s->d1->cookie_len != clienthello.dtls_cookie_len
|| memcmp(clienthello.dtls_cookie, s->d1->cookie,
s->d1->cookie_len) != 0) {
al = SSL_AD_HANDSHAKE_FAILURE;
SSLerr(SSL_F_TLS_PROCESS_CLIENT_HELLO, SSL_R_COOKIE_MISMATCH);
goto f_err;
@ -1104,7 +1146,7 @@ MSG_PROCESS_RETURN tls_process_client_hello(SSL *s, PACKET *pkt)
s->d1->cookie_verified = 1;
}
if (s->method->version == DTLS_ANY_VERSION) {
protverr = ssl_choose_server_version(s);
protverr = ssl_choose_server_version(s, &clienthello);
if (protverr != 0) {
SSLerr(SSL_F_TLS_PROCESS_CLIENT_HELLO, protverr);
s->version = s->client_version;
@ -1116,6 +1158,15 @@ MSG_PROCESS_RETURN tls_process_client_hello(SSL *s, PACKET *pkt)
s->hit = 0;
/* We need to do this before getting the session */
if (!tls_check_client_ems_support(s, &clienthello))
{
/* Only fails if the extension is malformed */
al = SSL_AD_DECODE_ERROR;
SSLerr(SSL_F_TLS_PROCESS_CLIENT_HELLO, SSL_R_CLIENTHELLO_TLSEXT);
goto f_err;
}
/*
* We don't allow resumption in a backwards compatible ClientHello.
* TODO(openssl-team): in TLS1.1+, session_id MUST be empty.
@ -1132,13 +1183,13 @@ MSG_PROCESS_RETURN tls_process_client_hello(SSL *s, PACKET *pkt)
* SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION setting will be
* ignored.
*/
if (is_v2_record ||
if (clienthello.isv2 ||
(s->new_session &&
(s->options & SSL_OP_NO_SESSION_RESUMPTION_ON_RENEGOTIATION))) {
if (!ssl_get_new_session(s, 1))
goto err;
} else {
i = ssl_get_prev_session(s, &extensions, &session_id);
i = ssl_get_prev_session(s, &clienthello);
/*
* Only resume if the session's version matches the negotiated
* version.
@ -1160,8 +1211,8 @@ MSG_PROCESS_RETURN tls_process_client_hello(SSL *s, PACKET *pkt)
}
}
if (ssl_bytes_to_cipher_list(s, &cipher_suites, &(ciphers),
is_v2_record, &al) == NULL) {
if (ssl_bytes_to_cipher_list(s, &clienthello.ciphersuites, &(ciphers),
clienthello.isv2, &al) == NULL) {
goto f_err;
}
@ -1196,13 +1247,12 @@ MSG_PROCESS_RETURN tls_process_client_hello(SSL *s, PACKET *pkt)
}
}
complen = PACKET_remaining(&compression);
for (loop = 0; loop < complen; loop++) {
if (PACKET_data(&compression)[loop] == 0)
for (loop = 0; loop < clienthello.compressions_len; loop++) {
if (clienthello.compressions[loop] == 0)
break;
}
if (loop >= complen) {
if (loop >= clienthello.compressions_len) {
/* no compress */
al = SSL_AD_DECODE_ERROR;
SSLerr(SSL_F_TLS_PROCESS_CLIENT_HELLO, SSL_R_NO_COMPRESSION_SPECIFIED);
@ -1210,11 +1260,9 @@ MSG_PROCESS_RETURN tls_process_client_hello(SSL *s, PACKET *pkt)
}
/* TLS extensions */
if (s->version >= SSL3_VERSION) {
if (!ssl_parse_clienthello_tlsext(s, &extensions)) {
SSLerr(SSL_F_TLS_PROCESS_CLIENT_HELLO, SSL_R_PARSE_TLSEXT);
goto err;
}
if (!ssl_parse_clienthello_tlsext(s, &clienthello)) {
SSLerr(SSL_F_TLS_PROCESS_CLIENT_HELLO, SSL_R_PARSE_TLSEXT);
goto err;
}
/*
@ -1305,11 +1353,11 @@ MSG_PROCESS_RETURN tls_process_client_hello(SSL *s, PACKET *pkt)
goto f_err;
}
/* Look for resumed method in compression list */
for (k = 0; k < complen; k++) {
if (PACKET_data(&compression)[k] == comp_id)
for (k = 0; k < clienthello.compressions_len; k++) {
if (clienthello.compressions[k] == comp_id)
break;
}
if (k >= complen) {
if (k >= clienthello.compressions_len) {
al = SSL_AD_ILLEGAL_PARAMETER;
SSLerr(SSL_F_TLS_PROCESS_CLIENT_HELLO,
SSL_R_REQUIRED_COMPRESSION_ALGORITHM_MISSING);
@ -1326,8 +1374,8 @@ MSG_PROCESS_RETURN tls_process_client_hello(SSL *s, PACKET *pkt)
for (m = 0; m < nn; m++) {
comp = sk_SSL_COMP_value(s->ctx->comp_methods, m);
v = comp->id;
for (o = 0; o < complen; o++) {
if (v == PACKET_data(&compression)[o]) {
for (o = 0; o < clienthello.compressions_len; o++) {
if (v == clienthello.compressions[o]) {
done = 1;
break;
}

View File

@ -1701,7 +1701,7 @@ static int tls1_alpn_handle_client_hello_late(SSL *s, int *al)
* Sadly we cannot differentiate 10.6, 10.7 and 10.8.4 (which work), from
* 10.8..10.8.3 (which don't work).
*/
static void ssl_check_for_safari(SSL *s, const PACKET *pkt)
static void ssl_check_for_safari(SSL *s, CLIENTHELLO_MSG *hello)
{
unsigned int type;
PACKET sni, tmppkt;
@ -1733,7 +1733,7 @@ static void ssl_check_for_safari(SSL *s, const PACKET *pkt)
/* Length of the common prefix (first two extensions). */
static const size_t kSafariCommonExtensionsLength = 18;
tmppkt = *pkt;
tmppkt = hello->extensions;
if (!PACKET_forward(&tmppkt, 2)
|| !PACKET_get_net_2(&tmppkt, &type)
@ -1763,11 +1763,10 @@ static void ssl_check_for_safari(SSL *s, const PACKET *pkt)
* Consumes the entire packet in |pkt|. Returns 1 on success and 0 on failure.
* Upon failure, sets |al| to the appropriate alert.
*/
static int ssl_scan_clienthello_tlsext(SSL *s, PACKET *pkt, int *al)
static int ssl_scan_clienthello_tlsext(SSL *s, CLIENTHELLO_MSG *hello, int *al)
{
unsigned int type;
size_t loop;
int renegotiate_seen = 0;
PACKET extensions;
*al = SSL_AD_DECODE_ERROR;
s->servername_done = 0;
@ -1789,7 +1788,7 @@ static int ssl_scan_clienthello_tlsext(SSL *s, PACKET *pkt, int *al)
#ifndef OPENSSL_NO_EC
if (s->options & SSL_OP_SAFARI_ECDHE_ECDSA_BUG)
ssl_check_for_safari(s, pkt);
ssl_check_for_safari(s, hello);
#endif /* !OPENSSL_NO_EC */
/* Clear any signature algorithms extension received */
@ -1804,32 +1803,21 @@ static int ssl_scan_clienthello_tlsext(SSL *s, PACKET *pkt, int *al)
s->srtp_profile = NULL;
if (PACKET_remaining(pkt) == 0)
goto ri_check;
if (!PACKET_as_length_prefixed_2(pkt, &extensions))
return 0;
if (!tls1_check_duplicate_extensions(&extensions))
return 0;
/*
* We parse all extensions to ensure the ClientHello is well-formed but,
* unless an extension specifies otherwise, we ignore extensions upon
* resumption.
*/
while (PACKET_get_net_2(&extensions, &type)) {
PACKET extension;
if (!PACKET_get_length_prefixed_2(&extensions, &extension))
return 0;
for (loop = 0; loop < hello->num_extensions; loop++) {
if (s->tlsext_debug_cb)
s->tlsext_debug_cb(s, 0, type, PACKET_data(&extension),
(int)PACKET_remaining(&extension),
s->tlsext_debug_cb(s, 0, hello->pre_proc_exts[loop].type,
PACKET_data(&hello->pre_proc_exts[loop].data),
PACKET_remaining(&hello->pre_proc_exts[loop].data),
s->tlsext_debug_arg);
if (type == TLSEXT_TYPE_renegotiate) {
if (!ssl_parse_clienthello_renegotiate_ext(s, &extension, al))
if (hello->pre_proc_exts[loop].type == TLSEXT_TYPE_renegotiate) {
if (!ssl_parse_clienthello_renegotiate_ext(s,
&hello->pre_proc_exts[loop].data, al))
return 0;
renegotiate_seen = 1;
} else if (s->version == SSL3_VERSION) {
@ -1859,11 +1847,12 @@ static int ssl_scan_clienthello_tlsext(SSL *s, PACKET *pkt, int *al)
*
*/
else if (type == TLSEXT_TYPE_server_name) {
else if (hello->pre_proc_exts[loop].type == TLSEXT_TYPE_server_name) {
unsigned int servname_type;
PACKET sni, hostname;
if (!PACKET_as_length_prefixed_2(&extension, &sni)
if (!PACKET_as_length_prefixed_2(&hello->pre_proc_exts[loop].data,
&sni)
/* ServerNameList must be at least 1 byte long. */
|| PACKET_remaining(&sni) == 0) {
return 0;
@ -1915,10 +1904,11 @@ static int ssl_scan_clienthello_tlsext(SSL *s, PACKET *pkt, int *al)
}
}
#ifndef OPENSSL_NO_SRP
else if (type == TLSEXT_TYPE_srp) {
else if (hello->pre_proc_exts[loop].type == TLSEXT_TYPE_srp) {
PACKET srp_I;
if (!PACKET_as_length_prefixed_1(&extension, &srp_I))
if (!PACKET_as_length_prefixed_1(&hello->pre_proc_exts[loop].data,
&srp_I))
return 0;
if (PACKET_contains_zero_byte(&srp_I))
@ -1936,10 +1926,12 @@ static int ssl_scan_clienthello_tlsext(SSL *s, PACKET *pkt, int *al)
#endif
#ifndef OPENSSL_NO_EC
else if (type == TLSEXT_TYPE_ec_point_formats) {
else if (hello->pre_proc_exts[loop].type
== TLSEXT_TYPE_ec_point_formats) {
PACKET ec_point_format_list;
if (!PACKET_as_length_prefixed_1(&extension, &ec_point_format_list)
if (!PACKET_as_length_prefixed_1(&hello->pre_proc_exts[loop].data,
&ec_point_format_list)
|| PACKET_remaining(&ec_point_format_list) == 0) {
return 0;
}
@ -1953,11 +1945,13 @@ static int ssl_scan_clienthello_tlsext(SSL *s, PACKET *pkt, int *al)
return 0;
}
}
} else if (type == TLSEXT_TYPE_elliptic_curves) {
} else if (hello->pre_proc_exts[loop].type
== TLSEXT_TYPE_elliptic_curves) {
PACKET elliptic_curve_list;
/* Each NamedCurve is 2 bytes and we must have at least 1. */
if (!PACKET_as_length_prefixed_2(&extension, &elliptic_curve_list)
if (!PACKET_as_length_prefixed_2(&hello->pre_proc_exts[loop].data,
&elliptic_curve_list)
|| PACKET_remaining(&elliptic_curve_list) == 0
|| (PACKET_remaining(&elliptic_curve_list) % 2) != 0) {
return 0;
@ -1974,19 +1968,22 @@ static int ssl_scan_clienthello_tlsext(SSL *s, PACKET *pkt, int *al)
}
}
#endif /* OPENSSL_NO_EC */
else if (type == TLSEXT_TYPE_session_ticket) {
else if (hello->pre_proc_exts[loop].type
== TLSEXT_TYPE_session_ticket) {
if (s->tls_session_ticket_ext_cb &&
!s->tls_session_ticket_ext_cb(s, PACKET_data(&extension),
(int)PACKET_remaining(&extension),
s->tls_session_ticket_ext_cb_arg))
{
!s->tls_session_ticket_ext_cb(s,
PACKET_data(&hello->pre_proc_exts[loop].data),
PACKET_remaining(&hello->pre_proc_exts[loop].data),
s->tls_session_ticket_ext_cb_arg)) {
*al = TLS1_AD_INTERNAL_ERROR;
return 0;
}
} else if (type == TLSEXT_TYPE_signature_algorithms) {
} else if (hello->pre_proc_exts[loop].type
== TLSEXT_TYPE_signature_algorithms) {
PACKET supported_sig_algs;
if (!PACKET_as_length_prefixed_2(&extension, &supported_sig_algs)
if (!PACKET_as_length_prefixed_2(&hello->pre_proc_exts[loop].data,
&supported_sig_algs)
|| (PACKET_remaining(&supported_sig_algs) % 2) != 0
|| PACKET_remaining(&supported_sig_algs) == 0) {
return 0;
@ -1998,8 +1995,9 @@ static int ssl_scan_clienthello_tlsext(SSL *s, PACKET *pkt, int *al)
return 0;
}
}
} else if (type == TLSEXT_TYPE_status_request) {
if (!PACKET_get_1(&extension,
} else if (hello->pre_proc_exts[loop].type
== TLSEXT_TYPE_status_request) {
if (!PACKET_get_1(&hello->pre_proc_exts[loop].data,
(unsigned int *)&s->tlsext_status_type)) {
return 0;
}
@ -2008,7 +2006,7 @@ static int ssl_scan_clienthello_tlsext(SSL *s, PACKET *pkt, int *al)
const unsigned char *ext_data;
PACKET responder_id_list, exts;
if (!PACKET_get_length_prefixed_2
(&extension, &responder_id_list))
(&hello->pre_proc_exts[loop].data, &responder_id_list))
return 0;
/*
@ -2058,7 +2056,8 @@ static int ssl_scan_clienthello_tlsext(SSL *s, PACKET *pkt, int *al)
}
/* Read in request_extensions */
if (!PACKET_as_length_prefixed_2(&extension, &exts))
if (!PACKET_as_length_prefixed_2(
&hello->pre_proc_exts[loop].data, &exts))
return 0;
if (PACKET_remaining(&exts) > 0) {
@ -2083,11 +2082,12 @@ static int ssl_scan_clienthello_tlsext(SSL *s, PACKET *pkt, int *al)
}
}
#ifndef OPENSSL_NO_HEARTBEATS
else if (SSL_IS_DTLS(s) && type == TLSEXT_TYPE_heartbeat) {
else if (SSL_IS_DTLS(s)
&& hello->pre_proc_exts[loop].type == TLSEXT_TYPE_heartbeat) {
unsigned int hbtype;
if (!PACKET_get_1(&extension, &hbtype)
|| PACKET_remaining(&extension)) {
if (!PACKET_get_1(&hello->pre_proc_exts[loop].data, &hbtype)
|| PACKET_remaining(&hello->pre_proc_exts[loop].data)) {
*al = SSL_AD_DECODE_ERROR;
return 0;
}
@ -2106,8 +2106,8 @@ static int ssl_scan_clienthello_tlsext(SSL *s, PACKET *pkt, int *al)
}
#endif
#ifndef OPENSSL_NO_NEXTPROTONEG
else if (type == TLSEXT_TYPE_next_proto_neg &&
s->s3->tmp.finish_md_len == 0) {
else if (hello->pre_proc_exts[loop].type == TLSEXT_TYPE_next_proto_neg
&& s->s3->tmp.finish_md_len == 0) {
/*-
* We shouldn't accept this extension on a
* renegotiation.
@ -2129,26 +2129,29 @@ static int ssl_scan_clienthello_tlsext(SSL *s, PACKET *pkt, int *al)
}
#endif
else if (type == TLSEXT_TYPE_application_layer_protocol_negotiation &&
s->s3->tmp.finish_md_len == 0) {
if (!tls1_alpn_handle_client_hello(s, &extension, al))
else if (hello->pre_proc_exts[loop].type
== TLSEXT_TYPE_application_layer_protocol_negotiation
&& s->s3->tmp.finish_md_len == 0) {
if (!tls1_alpn_handle_client_hello(s,
&hello->pre_proc_exts[loop].data, al))
return 0;
}
/* session ticket processed earlier */
#ifndef OPENSSL_NO_SRTP
else if (SSL_IS_DTLS(s) && SSL_get_srtp_profiles(s)
&& type == TLSEXT_TYPE_use_srtp) {
if (ssl_parse_clienthello_use_srtp_ext(s, &extension, al))
&& hello->pre_proc_exts[loop].type == TLSEXT_TYPE_use_srtp) {
if (ssl_parse_clienthello_use_srtp_ext(s,
&hello->pre_proc_exts[loop].data, al))
return 0;
}
#endif
else if (type == TLSEXT_TYPE_encrypt_then_mac &&
!(s->options & SSL_OP_NO_ENCRYPT_THEN_MAC))
else if (hello->pre_proc_exts[loop].type == TLSEXT_TYPE_encrypt_then_mac
&& !(s->options & SSL_OP_NO_ENCRYPT_THEN_MAC))
s->s3->flags |= TLS1_FLAGS_ENCRYPT_THEN_MAC;
/*
* Note: extended master secret extension handled in
* tls_check_serverhello_tlsext_early()
* tls_check_client_ems_support()
*/
/*
@ -2159,22 +2162,13 @@ static int ssl_scan_clienthello_tlsext(SSL *s, PACKET *pkt, int *al)
* ServerHello may be later returned.
*/
else if (!s->hit) {
if (custom_ext_parse(s, 1, type, PACKET_data(&extension),
PACKET_remaining(&extension), al) <= 0)
if (custom_ext_parse(s, 1, hello->pre_proc_exts[loop].type,
PACKET_data(&hello->pre_proc_exts[loop].data),
PACKET_remaining(&hello->pre_proc_exts[loop].data), al) <= 0)
return 0;
}
}
if (PACKET_remaining(pkt) != 0) {
/*
* tls1_check_duplicate_extensions should ensure this never happens.
*/
*al = SSL_AD_INTERNAL_ERROR;
return 0;
}
ri_check:
/* Need RI if renegotiating */
if (!renegotiate_seen && s->renegotiate &&
@ -2194,11 +2188,11 @@ static int ssl_scan_clienthello_tlsext(SSL *s, PACKET *pkt, int *al)
return 1;
}
int ssl_parse_clienthello_tlsext(SSL *s, PACKET *pkt)
int ssl_parse_clienthello_tlsext(SSL *s, CLIENTHELLO_MSG *hello)
{
int al = -1;
custom_ext_init(&s->cert->srv_ext);
if (ssl_scan_clienthello_tlsext(s, pkt, &al) <= 0) {
if (ssl_scan_clienthello_tlsext(s, hello, &al) <= 0) {
ssl3_send_alert(s, SSL3_AL_FATAL, al);
return 0;
}
@ -2793,16 +2787,23 @@ int ssl_parse_serverhello_tlsext(SSL *s, PACKET *pkt)
return 1;
}
static RAW_EXTENSION *get_extension_by_type(RAW_EXTENSION *exts, size_t numexts,
unsigned int type)
{
size_t loop;
for (loop = 0; loop < numexts; loop++) {
if (exts[loop].type == type)
return &exts[loop];
}
return NULL;
}
/*-
* Since the server cache lookup is done early on in the processing of the
* ClientHello and other operations depend on the result some extensions
* need to be handled at the same time.
* Gets the ticket information supplied by the client if any.
*
* Two extensions are currently handled, session ticket and extended master
* secret.
*
* session_id: ClientHello session ID.
* ext: ClientHello extensions (including length prefix)
* hello: The parsed ClientHello data
* ret: (output) on return, if a ticket was decrypted, then this is set to
* point to the resulting session.
*
@ -2826,116 +2827,102 @@ int ssl_parse_serverhello_tlsext(SSL *s, PACKET *pkt)
* a session ticket or we couldn't use the one it gave us, or if
* s->ctx->tlsext_ticket_key_cb asked to renew the client's ticket.
* Otherwise, s->tlsext_ticket_expected is set to 0.
*
* For extended master secret flag is set if the extension is present.
*
*/
int tls_check_serverhello_tlsext_early(SSL *s, const PACKET *ext,
const PACKET *session_id,
SSL_SESSION **ret)
int tls_get_ticket_from_client(SSL *s, CLIENTHELLO_MSG *hello,
SSL_SESSION **ret)
{
unsigned int i;
PACKET local_ext = *ext;
int retv = -1;
int have_ticket = 0;
int use_ticket = tls_use_ticket(s);
int retv;
const unsigned char *etick;
size_t size;
RAW_EXTENSION *ticketext;
*ret = NULL;
s->tlsext_ticket_expected = 0;
s->s3->flags &= ~TLS1_FLAGS_RECEIVED_EXTMS;
/*
* If tickets disabled behave as if no ticket present to permit stateful
* resumption.
*/
if ((s->version <= SSL3_VERSION))
if (s->version <= SSL3_VERSION || !tls_use_ticket(s))
return 0;
if (!PACKET_get_net_2(&local_ext, &i)) {
retv = 0;
goto end;
ticketext = get_extension_by_type(hello->pre_proc_exts,
hello->num_extensions,
TLSEXT_TYPE_session_ticket);
if (ticketext == NULL)
return 0;
size = PACKET_remaining(&ticketext->data);
if (size == 0) {
/*
* The client will accept a ticket but doesn't currently have
* one.
*/
s->tlsext_ticket_expected = 1;
return 1;
}
while (PACKET_remaining(&local_ext) >= 4) {
unsigned int type, size;
if (!PACKET_get_net_2(&local_ext, &type)
|| !PACKET_get_net_2(&local_ext, &size)) {
/* Shouldn't ever happen */
retv = -1;
goto end;
}
if (PACKET_remaining(&local_ext) < size) {
retv = 0;
goto end;
}
if (type == TLSEXT_TYPE_session_ticket && use_ticket) {
int r;
const unsigned char *etick;
/* Duplicate extension */
if (have_ticket != 0) {
retv = -1;
goto end;
}
have_ticket = 1;
if (size == 0) {
/*
* The client will accept a ticket but doesn't currently have
* one.
*/
s->tlsext_ticket_expected = 1;
retv = 1;
continue;
}
if (s->tls_session_secret_cb) {
/*
* Indicate that the ticket couldn't be decrypted rather than
* generating the session from ticket now, trigger
* abbreviated handshake based on external mechanism to
* calculate the master secret later.
*/
retv = 2;
continue;
}
if (!PACKET_get_bytes(&local_ext, &etick, size)) {
/* Shouldn't ever happen */
retv = -1;
goto end;
}
r = tls_decrypt_ticket(s, etick, size, PACKET_data(session_id),
PACKET_remaining(session_id), ret);
switch (r) {
case 2: /* ticket couldn't be decrypted */
s->tlsext_ticket_expected = 1;
retv = 2;
break;
case 3: /* ticket was decrypted */
retv = r;
break;
case 4: /* ticket decrypted but need to renew */
s->tlsext_ticket_expected = 1;
retv = 3;
break;
default: /* fatal error */
retv = -1;
break;
}
continue;
} else {
if (type == TLSEXT_TYPE_extended_master_secret)
s->s3->flags |= TLS1_FLAGS_RECEIVED_EXTMS;
if (!PACKET_forward(&local_ext, size)) {
retv = -1;
goto end;
}
}
if (s->tls_session_secret_cb) {
/*
* Indicate that the ticket couldn't be decrypted rather than
* generating the session from ticket now, trigger
* abbreviated handshake based on external mechanism to
* calculate the master secret later.
*/
return 2;
}
if (have_ticket == 0)
retv = 0;
end:
return retv;
if (!PACKET_get_bytes(&ticketext->data, &etick, size)) {
/* Shouldn't ever happen */
return -1;
}
retv = tls_decrypt_ticket(s, etick, size, hello->session_id,
hello->session_id_len, ret);
switch (retv) {
case 2: /* ticket couldn't be decrypted */
s->tlsext_ticket_expected = 1;
return 2;
case 3: /* ticket was decrypted */
return 3;
case 4: /* ticket decrypted but need to renew */
s->tlsext_ticket_expected = 1;
return 3;
default: /* fatal error */
return -1;
}
}
/*
* Sets the extended master secret flag is set if the extension is present
* in the ClientHello
*/
int tls_check_client_ems_support(SSL *s, CLIENTHELLO_MSG *hello)
{
RAW_EXTENSION *emsext;
s->s3->flags &= ~TLS1_FLAGS_RECEIVED_EXTMS;
if (s->version <= SSL3_VERSION)
return 1;
emsext = get_extension_by_type(hello->pre_proc_exts, hello->num_extensions,
TLSEXT_TYPE_extended_master_secret);
/*
* No extensions is a success - we have successfully discovered that the
* client doesn't support EMS.
*/
if (emsext == NULL)
return 1;
/* The extensions must always be empty */
if (PACKET_remaining(&emsext->data) != 0)
return 0;
s->s3->flags |= TLS1_FLAGS_RECEIVED_EXTMS;
return 1;
}
/*-