Support session-specific ALPNs for clients, and specifying multiple ALPNs.
gfe-relnote: n/a (no functional change)
PiperOrigin-RevId: 266192245
Change-Id: Id0921d36b2c32c7df92a4a528ec19d9a28b826b0
diff --git a/quic/core/tls_client_handshaker.cc b/quic/core/tls_client_handshaker.cc
index 8e2d2bb..a410f81 100644
--- a/quic/core/tls_client_handshaker.cc
+++ b/quic/core/tls_client_handshaker.cc
@@ -15,8 +15,6 @@
namespace quic {
-std::string* quic_alpn_override_on_client_for_tests = nullptr;
-
TlsClientHandshaker::ProofVerifierCallbackImpl::ProofVerifierCallbackImpl(
TlsClientHandshaker* parent)
: parent_(parent) {}
@@ -78,32 +76,10 @@
return false;
}
- std::string alpn_string = AlpnForVersion(session()->connection()->version());
- if (quic_alpn_override_on_client_for_tests != nullptr) {
- alpn_string = *quic_alpn_override_on_client_for_tests;
- }
- if (alpn_string.length() > std::numeric_limits<uint8_t>::max()) {
- QUIC_BUG << "ALPN too long: '" << alpn_string << "'";
- CloseConnection(QUIC_HANDSHAKE_FAILED,
- "Client configured ALPN is too long");
+ if (!SetAlpn()) {
+ CloseConnection(QUIC_HANDSHAKE_FAILED, "Client failed to set ALPN");
return false;
}
- const uint8_t alpn_length = alpn_string.length();
- if (alpn_length > 0) {
- // SSL_set_alpn_protos expects a sequence of one-byte-length-prefixed
- // strings so we copy alpn_string to a new buffer that has the length
- // in alpn[0].
- uint8_t alpn[std::numeric_limits<uint8_t>::max() + 1];
- alpn[0] = alpn_length;
- memcpy(reinterpret_cast<char*>(alpn + 1), alpn_string.data(), alpn_length);
- if (SSL_set_alpn_protos(ssl(), alpn,
- static_cast<unsigned>(alpn_length) + 1) != 0) {
- QUIC_BUG << "Failed to set ALPN: '" << alpn_string << "'";
- CloseConnection(QUIC_HANDSHAKE_FAILED, "Client failed to set ALPN");
- return false;
- }
- }
- QUIC_DLOG(INFO) << "Client using ALPN: '" << alpn_string << "'";
// Set the Transport Parameters to send in the ClientHello
if (!SetTransportParameters()) {
@@ -117,6 +93,46 @@
return session()->connection()->connected();
}
+static bool IsValidAlpn(const std::string& alpn_string) {
+ return alpn_string.length() <= std::numeric_limits<uint8_t>::max();
+}
+
+bool TlsClientHandshaker::SetAlpn() {
+ std::vector<std::string> alpns = session()->GetAlpnsToOffer();
+ if (alpns.empty()) {
+ if (allow_empty_alpn_for_tests_) {
+ return true;
+ }
+
+ QUIC_BUG << "ALPN missing";
+ return false;
+ }
+ if (!std::all_of(alpns.begin(), alpns.end(), IsValidAlpn)) {
+ QUIC_BUG << "ALPN too long";
+ return false;
+ }
+
+ // SSL_set_alpn_protos expects a sequence of one-byte-length-prefixed
+ // strings.
+ uint8_t alpn[1024];
+ QuicDataWriter alpn_writer(sizeof(alpn), reinterpret_cast<char*>(alpn));
+ bool success = true;
+ for (const std::string& alpn_string : alpns) {
+ success = success && alpn_writer.WriteUInt8(alpn_string.size()) &&
+ alpn_writer.WriteStringPiece(alpn_string);
+ }
+ success =
+ success && (SSL_set_alpn_protos(ssl(), alpn, alpn_writer.length()) == 0);
+ if (!success) {
+ QUIC_BUG << "Failed to set ALPN: "
+ << QuicTextUtils::HexDump(
+ QuicStringPiece(alpn_writer.data(), alpn_writer.length()));
+ return false;
+ }
+ QUIC_DLOG(INFO) << "Client using ALPN: '" << alpns[0] << "'";
+ return true;
+}
+
bool TlsClientHandshaker::SetTransportParameters() {
TransportParameters params;
params.perspective = Perspective::IS_CLIENT;
