Add support for the new QUIC TLS extension codepoint
IETF QUIC draft 33 is replacing the TLS extension
codepoint for QUIC transport parameters from 0xffa5
to 57. To support multiple versions of Chrome, we
need to support both codepoints in BoringSSL. This
CL adds support for the new codepoint in a way that
can be enabled on individual connections.
Change-Id: I3bf06ea0710702c0dc45bb3ff2e3d772e9f87f9b
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/44585
Commit-Queue: David Benjamin <davidben@google.com>
Reviewed-by: David Benjamin <davidben@google.com>
diff --git a/ssl/t1_lib.cc b/ssl/t1_lib.cc
index 955eae7..5affccc 100644
--- a/ssl/t1_lib.cc
+++ b/ssl/t1_lib.cc
@@ -2750,8 +2750,8 @@
// QUIC Transport Parameters
-static bool ext_quic_transport_params_add_clienthello(SSL_HANDSHAKE *hs,
- CBB *out) {
+static bool ext_quic_transport_params_add_clienthello_impl(
+ SSL_HANDSHAKE *hs, CBB *out, bool use_legacy_codepoint) {
if (hs->config->quic_transport_params.empty() && !hs->ssl->quic_method) {
return true;
}
@@ -2763,9 +2763,18 @@
return false;
}
assert(hs->min_version > TLS1_2_VERSION);
+ if (use_legacy_codepoint != hs->config->quic_use_legacy_codepoint) {
+ // Do nothing, we'll send the other codepoint.
+ return true;
+ }
+
+ uint16_t extension_type = TLSEXT_TYPE_quic_transport_parameters;
+ if (hs->config->quic_use_legacy_codepoint) {
+ extension_type = TLSEXT_TYPE_quic_transport_parameters_legacy;
+ }
CBB contents;
- if (!CBB_add_u16(out, TLSEXT_TYPE_quic_transport_parameters) ||
+ if (!CBB_add_u16(out, extension_type) ||
!CBB_add_u16_length_prefixed(out, &contents) ||
!CBB_add_bytes(&contents, hs->config->quic_transport_params.data(),
hs->config->quic_transport_params.size()) ||
@@ -2775,31 +2784,61 @@
return true;
}
-static bool ext_quic_transport_params_parse_serverhello(SSL_HANDSHAKE *hs,
- uint8_t *out_alert,
- CBS *contents) {
+static bool ext_quic_transport_params_add_clienthello(SSL_HANDSHAKE *hs,
+ CBB *out) {
+ return ext_quic_transport_params_add_clienthello_impl(
+ hs, out, /*use_legacy_codepoint=*/false);
+}
+
+static bool ext_quic_transport_params_add_clienthello_legacy(SSL_HANDSHAKE *hs,
+ CBB *out) {
+ return ext_quic_transport_params_add_clienthello_impl(
+ hs, out, /*use_legacy_codepoint=*/true);
+}
+
+static bool ext_quic_transport_params_parse_serverhello_impl(
+ SSL_HANDSHAKE *hs, uint8_t *out_alert, CBS *contents,
+ bool used_legacy_codepoint) {
SSL *const ssl = hs->ssl;
if (contents == nullptr) {
+ if (used_legacy_codepoint != hs->config->quic_use_legacy_codepoint) {
+ // Silently ignore because we expect the other QUIC codepoint.
+ return true;
+ }
if (!ssl->quic_method) {
return true;
}
- assert(ssl->quic_method);
*out_alert = SSL_AD_MISSING_EXTENSION;
return false;
}
- if (!ssl->quic_method) {
- *out_alert = SSL_AD_UNSUPPORTED_EXTENSION;
- return false;
- }
- // QUIC requires TLS 1.3.
+ // The extensions parser will check for unsolicited extensions before
+ // calling the callback.
+ assert(ssl->quic_method != nullptr);
assert(ssl_protocol_version(ssl) == TLS1_3_VERSION);
-
+ assert(used_legacy_codepoint == hs->config->quic_use_legacy_codepoint);
return ssl->s3->peer_quic_transport_params.CopyFrom(*contents);
}
-static bool ext_quic_transport_params_parse_clienthello(SSL_HANDSHAKE *hs,
+static bool ext_quic_transport_params_parse_serverhello(SSL_HANDSHAKE *hs,
uint8_t *out_alert,
CBS *contents) {
+ return ext_quic_transport_params_parse_serverhello_impl(
+ hs, out_alert, contents, /*used_legacy_codepoint=*/false);
+}
+
+static bool ext_quic_transport_params_parse_serverhello_legacy(
+ SSL_HANDSHAKE *hs, uint8_t *out_alert, CBS *contents) {
+ return ext_quic_transport_params_parse_serverhello_impl(
+ hs, out_alert, contents, /*used_legacy_codepoint=*/true);
+}
+
+static bool ext_quic_transport_params_parse_clienthello_impl(
+ SSL_HANDSHAKE *hs, uint8_t *out_alert, CBS *contents,
+ bool used_legacy_codepoint) {
+ if (used_legacy_codepoint != hs->config->quic_use_legacy_codepoint) {
+ // Silently ignore because we expect the other QUIC codepoint.
+ return true;
+ }
SSL *const ssl = hs->ssl;
if (!contents) {
if (!ssl->quic_method) {
@@ -2822,17 +2861,39 @@
return ssl->s3->peer_quic_transport_params.CopyFrom(*contents);
}
-static bool ext_quic_transport_params_add_serverhello(SSL_HANDSHAKE *hs,
- CBB *out) {
+static bool ext_quic_transport_params_parse_clienthello(SSL_HANDSHAKE *hs,
+ uint8_t *out_alert,
+ CBS *contents) {
+ return ext_quic_transport_params_parse_clienthello_impl(
+ hs, out_alert, contents, /*used_legacy_codepoint=*/false);
+}
+
+static bool ext_quic_transport_params_parse_clienthello_legacy(
+ SSL_HANDSHAKE *hs, uint8_t *out_alert, CBS *contents) {
+ return ext_quic_transport_params_parse_clienthello_impl(
+ hs, out_alert, contents, /*used_legacy_codepoint=*/true);
+}
+
+static bool ext_quic_transport_params_add_serverhello_impl(
+ SSL_HANDSHAKE *hs, CBB *out, bool use_legacy_codepoint) {
assert(hs->ssl->quic_method != nullptr);
if (hs->config->quic_transport_params.empty()) {
// Transport parameters must be set when using QUIC.
OPENSSL_PUT_ERROR(SSL, SSL_R_QUIC_TRANSPORT_PARAMETERS_MISCONFIGURED);
return false;
}
+ if (use_legacy_codepoint != hs->config->quic_use_legacy_codepoint) {
+ // Do nothing, we'll send the other codepoint.
+ return true;
+ }
+
+ uint16_t extension_type = TLSEXT_TYPE_quic_transport_parameters;
+ if (hs->config->quic_use_legacy_codepoint) {
+ extension_type = TLSEXT_TYPE_quic_transport_parameters_legacy;
+ }
CBB contents;
- if (!CBB_add_u16(out, TLSEXT_TYPE_quic_transport_parameters) ||
+ if (!CBB_add_u16(out, extension_type) ||
!CBB_add_u16_length_prefixed(out, &contents) ||
!CBB_add_bytes(&contents, hs->config->quic_transport_params.data(),
hs->config->quic_transport_params.size()) ||
@@ -2843,6 +2904,18 @@
return true;
}
+static bool ext_quic_transport_params_add_serverhello(SSL_HANDSHAKE *hs,
+ CBB *out) {
+ return ext_quic_transport_params_add_serverhello_impl(
+ hs, out, /*use_legacy_codepoint=*/false);
+}
+
+static bool ext_quic_transport_params_add_serverhello_legacy(SSL_HANDSHAKE *hs,
+ CBB *out) {
+ return ext_quic_transport_params_add_serverhello_impl(
+ hs, out, /*use_legacy_codepoint=*/true);
+}
+
// Delegated credentials.
//
// https://tools.ietf.org/html/draft-ietf-tls-subcerts
@@ -3283,6 +3356,14 @@
ext_quic_transport_params_add_serverhello,
},
{
+ TLSEXT_TYPE_quic_transport_parameters_legacy,
+ NULL,
+ ext_quic_transport_params_add_clienthello_legacy,
+ ext_quic_transport_params_parse_serverhello_legacy,
+ ext_quic_transport_params_parse_clienthello_legacy,
+ ext_quic_transport_params_add_serverhello_legacy,
+ },
+ {
TLSEXT_TYPE_token_binding,
NULL,
ext_token_binding_add_clienthello,
