wbrawner/openssl
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

Add server side support for supported_versions extension

Browse source 
Reviewed-by: Rich Salz <rsalz@openssl.org>
This commit is contained in:
Matt Caswell 2016-10-23 00:41:11 +01:00
parent 5506e835a8
commit cd99883755
8 changed files with 106 additions and 15 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

3
ssl/ssl_locl.h
View file

@ -2077,6 +2077,9 @@ __owur int dtls1_process_heartbeat(SSL *s, unsigned char *p,
size_t length);
# endif
__owur RAW_EXTENSION *tls_get_extension_by_type(RAW_EXTENSION *exts,
size_t numexts,
unsigned int type);
__owur int tls_get_ticket_from_client(SSL *s, CLIENTHELLO_MSG *hello,
SSL_SESSION **ret);
__owur int tls_check_client_ems_support(SSL *s, const CLIENTHELLO_MSG *hello);

7
ssl/statem/statem_clnt.c
View file

@ -779,8 +779,13 @@ int tls_construct_client_hello(SSL *s, WPACKET *pkt)
* TLS 1.0 and renegotiating with TLS 1.2. We do this by using
* client_version in client hello and not resetting it to
* the negotiated version.
*
* For TLS 1.3 we always set the ClientHello version to 1.2 and rely on the
* supported_versions extension for the reall supported versions.
*/
if (!WPACKET_put_bytes_u16(pkt, s->client_version)
if (!WPACKET_put_bytes_u16(pkt,
(!SSL_IS_DTLS(s) && s->client_version >= TLS1_3_VERSION)
? TLS1_2_VERSION : s->client_version)
|| !WPACKET_memcpy(pkt, s->s3->client_random, SSL3_RANDOM_SIZE)) {
SSLerr(SSL_F_TLS_CONSTRUCT_CLIENT_HELLO, ERR_R_INTERNAL_ERROR);
return 0;

68
ssl/statem/statem_lib.c
View file

@ -996,6 +996,7 @@ int ssl_choose_server_version(SSL *s, CLIENTHELLO_MSG *hello)
const version_info *vent;
const version_info *table;
int disabled = 0;
RAW_EXTENSION *suppversions;
s->client_version = client_version;
@ -1019,6 +1020,73 @@ int ssl_choose_server_version(SSL *s, CLIENTHELLO_MSG *hello)
break;
}
suppversions = tls_get_extension_by_type(hello->pre_proc_exts,
hello->num_extensions,
TLSEXT_TYPE_supported_versions);
/*
* TODO(TLS1.3): We only look at this if our max protocol version is TLS1.3
* or above. Should we allow it for lower versions too?
*/
if (suppversions != NULL && !SSL_IS_DTLS(s)
&& (s->max_proto_version == 0
|| TLS1_3_VERSION <= s->max_proto_version)) {
unsigned int candidate_vers = 0;
unsigned int best_vers = 0;
const SSL_METHOD *best_method = NULL;
PACKET versionslist;
if (!PACKET_get_length_prefixed_1(&suppversions->data, &versionslist)
|| PACKET_remaining(&suppversions->data) != 0) {
/* Trailing or invalid data? */
return SSL_R_LENGTH_MISMATCH;
}
while (PACKET_get_net_2(&versionslist, &candidate_vers)) {
/* TODO(TLS1.3): Remove this before release */
if (candidate_vers == TLS1_3_VERSION_DRAFT)
candidate_vers = TLS1_3_VERSION;
if ((int)candidate_vers > s->client_version)
s->client_version = candidate_vers;
if (version_cmp(s, candidate_vers, best_vers) <= 0)
continue;
for (vent = table;
vent->version != 0 && vent->version != (int)candidate_vers;
++vent);
if (vent->version != 0) {
const SSL_METHOD *method;
method = vent->smeth();
if (ssl_method_error(s, method) == 0) {
best_vers = candidate_vers;
best_method = method;
}
}
}
if (PACKET_remaining(&versionslist) != 0) {
/* Trailing data? */
return SSL_R_LENGTH_MISMATCH;
}
if (best_vers > 0) {
s->version = best_vers;
s->method = best_method;
return 0;
}
return SSL_R_UNSUPPORTED_PROTOCOL;
}
/*
* If the supported versions extension isn't present, then the highest
* version we can negotiate is TLSv1.2
*/
if (version_cmp(s, client_version, TLS1_3_VERSION) >= 0)
client_version = TLS1_2_VERSION;
/*
* No supported versions extension, so we just use the version supplied in
* the ClientHello.
*/
for (vent = table; vent->version != 0; ++vent) {
const SSL_METHOD *method;

15
ssl/t1_lib.c
View file

@ -2826,8 +2826,8 @@ int ssl_parse_serverhello_tlsext(SSL *s, PACKET *pkt)
*
* Returns a pointer to the found RAW_EXTENSION data, or NULL if not found.
*/
static RAW_EXTENSION *get_extension_by_type(RAW_EXTENSION *exts, size_t numexts,
unsigned int type)
RAW_EXTENSION *tls_get_extension_by_type(RAW_EXTENSION *exts, size_t numexts,
unsigned int type)
{
size_t loop;
@ -2885,9 +2885,9 @@ int tls_get_ticket_from_client(SSL *s, CLIENTHELLO_MSG *hello,
if (s->version <= SSL3_VERSION || !tls_use_ticket(s))
return 0;
ticketext = get_extension_by_type(hello->pre_proc_exts,
hello->num_extensions,
TLSEXT_TYPE_session_ticket);
ticketext = tls_get_extension_by_type(hello->pre_proc_exts,
hello->num_extensions,
TLSEXT_TYPE_session_ticket);
if (ticketext == NULL)
return 0;
@ -2948,8 +2948,9 @@ int tls_check_client_ems_support(SSL *s, const CLIENTHELLO_MSG *hello)
if (s->version <= SSL3_VERSION)
return 1;
emsext = get_extension_by_type(hello->pre_proc_exts, hello->num_extensions,
TLSEXT_TYPE_extended_master_secret);
emsext = tls_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

9
test/recipes/70-test_sslvertol.t
View file

@ -34,15 +34,18 @@ my $proxy = TLSProxy::Proxy->new(
(!$ENV{HARNESS_ACTIVE} || $ENV{HARNESS_VERBOSE})
);
#Test 1: Asking for TLS1.3 should pass
my $client_version = TLSProxy::Record::VERS_TLS_1_3;
#Test 1: Asking for TLS1.4 should pass
my $client_version = TLSProxy::Record::VERS_TLS_1_4;
#We don't want the supported versions extension for this test
$proxy->clientflags("-no_tls1_3");
$proxy->start() or plan skip_all => "Unable to start up Proxy for tests";
plan tests => 2;
ok(TLSProxy::Message->success(), "Version tolerance test, TLS 1.3");
ok(TLSProxy::Message->success(), "Version tolerance test, TLS 1.4");
#Test 2: Testing something below SSLv3 should fail
$client_version = TLSProxy::Record::VERS_SSL_3_0 - 1;
$proxy->clear();
$proxy->clientflags("-no_tls1_3");
$proxy->start();
ok(TLSProxy::Message->fail(), "Version tolerance test, SSL < 3.0");

4
test/ssl-tests/17-renegotiate.conf
View file

@ -18,6 +18,7 @@ client = 0-renegotiate-client-no-resume-client
[0-renegotiate-client-no-resume-server]
Certificate = ${ENV::TEST_CERTS_DIR}/servercert.pem
CipherString = DEFAULT
MaxProtocol = TLSv1.2
Options = NoResumptionOnRenegotiation
PrivateKey = ${ENV::TEST_CERTS_DIR}/serverkey.pem
@ -45,6 +46,7 @@ client = 1-renegotiate-client-resume-client
[1-renegotiate-client-resume-server]
Certificate = ${ENV::TEST_CERTS_DIR}/servercert.pem
CipherString = DEFAULT
MaxProtocol = TLSv1.2
PrivateKey = ${ENV::TEST_CERTS_DIR}/serverkey.pem
[1-renegotiate-client-resume-client]
@ -71,6 +73,7 @@ client = 2-renegotiate-server-no-resume-client
[2-renegotiate-server-no-resume-server]
Certificate = ${ENV::TEST_CERTS_DIR}/servercert.pem
CipherString = DEFAULT
MaxProtocol = TLSv1.2
Options = NoResumptionOnRenegotiation
PrivateKey = ${ENV::TEST_CERTS_DIR}/serverkey.pem
@ -98,6 +101,7 @@ client = 3-renegotiate-server-resume-client
[3-renegotiate-server-resume-server]
Certificate = ${ENV::TEST_CERTS_DIR}/servercert.pem
CipherString = DEFAULT
MaxProtocol = TLSv1.2
PrivateKey = ${ENV::TEST_CERTS_DIR}/serverkey.pem
[3-renegotiate-server-resume-client]

14
test/ssl-tests/17-renegotiate.conf.in
View file

@ -19,7 +19,8 @@ our @tests = (
{
name => "renegotiate-client-no-resume",
server => {
"Options" => "NoResumptionOnRenegotiation"
"Options" => "NoResumptionOnRenegotiation",
"MaxProtocol" => "TLSv1.2"
},
client => {},
test => {
@ -31,7 +32,9 @@ our @tests = (
},
{
name => "renegotiate-client-resume",
server => {},
server => {
"MaxProtocol" => "TLSv1.2"
},
client => {},
test => {
"Method" => "TLS",
@ -43,7 +46,8 @@ our @tests = (
{
name => "renegotiate-server-no-resume",
server => {
"Options" => "NoResumptionOnRenegotiation"
"Options" => "NoResumptionOnRenegotiation",
"MaxProtocol" => "TLSv1.2"
},
client => {},
test => {
@ -55,7 +59,9 @@ our @tests = (
},
{
name => "renegotiate-server-resume",
server => {},
server => {
"MaxProtocol" => "TLSv1.2"
},
client => {},
test => {
"Method" => "TLS",

1
util/TLSProxy/Record.pm
View file

@ -35,6 +35,7 @@ my %record_type = (
);
use constant {
VERS_TLS_1_4 => 773,
VERS_TLS_1_3 => 772,
VERS_TLS_1_2 => 771,
VERS_TLS_1_1 => 770,