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// Copyright (c) 2016 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "net/tools/quic/chlo_extractor.h"
#include "net/quic/core/crypto/crypto_framer.h"
#include "net/quic/core/crypto/crypto_handshake_message.h"
#include "net/quic/core/crypto/crypto_protocol.h"
#include "net/quic/core/crypto/quic_decrypter.h"
#include "net/quic/core/crypto/quic_encrypter.h"
#include "net/quic/core/quic_framer.h"
#include "net/quic/platform/api/quic_string_piece.h"
#include "net/quic/platform/api/quic_text_utils.h"
namespace net {
namespace {
class ChloFramerVisitor : public QuicFramerVisitorInterface,
public CryptoFramerVisitorInterface {
public:
ChloFramerVisitor(QuicFramer* framer,
const QuicTagVector& create_session_tag_indicators,
ChloExtractor::Delegate* delegate);
~ChloFramerVisitor() override = default;
// QuicFramerVisitorInterface implementation
void OnError(QuicFramer* framer) override {}
bool OnProtocolVersionMismatch(ParsedQuicVersion version) override;
void OnPacket() override {}
void OnPublicResetPacket(const QuicPublicResetPacket& packet) override {}
void OnVersionNegotiationPacket(
const QuicVersionNegotiationPacket& packet) override {}
bool OnUnauthenticatedPublicHeader(const QuicPacketHeader& header) override;
bool OnUnauthenticatedHeader(const QuicPacketHeader& header) override;
void OnDecryptedPacket(EncryptionLevel level) override {}
bool OnPacketHeader(const QuicPacketHeader& header) override;
bool OnStreamFrame(const QuicStreamFrame& frame) override;
bool OnAckFrame(const QuicAckFrame& frame) override;
bool OnAckFrameStart(QuicPacketNumber largest_acked,
QuicTime::Delta ack_delay_time) override;
bool OnAckRange(QuicPacketNumber start,
QuicPacketNumber end,
bool last_range) override;
bool OnStopWaitingFrame(const QuicStopWaitingFrame& frame) override;
bool OnPingFrame(const QuicPingFrame& frame) override;
bool OnRstStreamFrame(const QuicRstStreamFrame& frame) override;
bool OnConnectionCloseFrame(const QuicConnectionCloseFrame& frame) override;
bool OnGoAwayFrame(const QuicGoAwayFrame& frame) override;
bool OnWindowUpdateFrame(const QuicWindowUpdateFrame& frame) override;
bool OnBlockedFrame(const QuicBlockedFrame& frame) override;
bool OnPaddingFrame(const QuicPaddingFrame& frame) override;
void OnPacketComplete() override {}
// CryptoFramerVisitorInterface implementation.
void OnError(CryptoFramer* framer) override;
void OnHandshakeMessage(const CryptoHandshakeMessage& message) override;
bool found_chlo() { return found_chlo_; }
bool chlo_contains_tags() { return chlo_contains_tags_; }
private:
QuicFramer* framer_;
const QuicTagVector& create_session_tag_indicators_;
ChloExtractor::Delegate* delegate_;
bool found_chlo_;
bool chlo_contains_tags_;
QuicConnectionId connection_id_;
};
ChloFramerVisitor::ChloFramerVisitor(
QuicFramer* framer,
const QuicTagVector& create_session_tag_indicators,
ChloExtractor::Delegate* delegate)
: framer_(framer),
create_session_tag_indicators_(create_session_tag_indicators),
delegate_(delegate),
found_chlo_(false),
chlo_contains_tags_(false),
connection_id_(0) {}
bool ChloFramerVisitor::OnProtocolVersionMismatch(ParsedQuicVersion version) {
if (!framer_->IsSupportedVersion(version)) {
return false;
}
framer_->set_version(version);
return true;
}
bool ChloFramerVisitor::OnUnauthenticatedPublicHeader(
const QuicPacketHeader& header) {
connection_id_ = header.connection_id;
return true;
}
bool ChloFramerVisitor::OnUnauthenticatedHeader(
const QuicPacketHeader& header) {
return true;
}
bool ChloFramerVisitor::OnPacketHeader(const QuicPacketHeader& header) {
return true;
}
bool ChloFramerVisitor::OnStreamFrame(const QuicStreamFrame& frame) {
QuicStringPiece data(frame.data_buffer, frame.data_length);
if (frame.stream_id == kCryptoStreamId && frame.offset == 0 &&
QuicTextUtils::StartsWith(data, "CHLO")) {
CryptoFramer crypto_framer;
crypto_framer.set_visitor(this);
if (!crypto_framer.ProcessInput(data, Perspective::IS_SERVER)) {
return false;
}
if (FLAGS_quic_reloadable_flag_quic_inspect_chlo_tags) {
// Interrogate the crypto framer and see if there are any
// intersecting tags between what we saw in the maybe-CHLO and the
// indicator set.
for (const QuicTag tag : create_session_tag_indicators_) {
if (crypto_framer.HasTag(tag)) {
chlo_contains_tags_ = true;
}
}
if (chlo_contains_tags_ && delegate_) {
// Unfortunately, because this is a partial CHLO,
// OnHandshakeMessage was never called, so the ALPN was never
// extracted. Fake it up a bit and send it to the delegate so that
// the correct dispatch can happen.
crypto_framer.ForceHandshake();
}
}
}
return true;
}
bool ChloFramerVisitor::OnAckFrame(const QuicAckFrame& frame) {
return true;
}
bool ChloFramerVisitor::OnAckFrameStart(QuicPacketNumber /*largest_acked*/,
QuicTime::Delta /*ack_delay_time*/) {
return true;
}
bool ChloFramerVisitor::OnAckRange(QuicPacketNumber /*start*/,
QuicPacketNumber /*end*/,
bool /*last_range*/) {
return true;
}
bool ChloFramerVisitor::OnStopWaitingFrame(const QuicStopWaitingFrame& frame) {
return true;
}
bool ChloFramerVisitor::OnPingFrame(const QuicPingFrame& frame) {
return true;
}
bool ChloFramerVisitor::OnRstStreamFrame(const QuicRstStreamFrame& frame) {
return true;
}
bool ChloFramerVisitor::OnConnectionCloseFrame(
const QuicConnectionCloseFrame& frame) {
return true;
}
bool ChloFramerVisitor::OnGoAwayFrame(const QuicGoAwayFrame& frame) {
return true;
}
bool ChloFramerVisitor::OnWindowUpdateFrame(
const QuicWindowUpdateFrame& frame) {
return true;
}
bool ChloFramerVisitor::OnBlockedFrame(const QuicBlockedFrame& frame) {
return true;
}
bool ChloFramerVisitor::OnPaddingFrame(const QuicPaddingFrame& frame) {
return true;
}
void ChloFramerVisitor::OnError(CryptoFramer* framer) {}
void ChloFramerVisitor::OnHandshakeMessage(
const CryptoHandshakeMessage& message) {
if (delegate_ != nullptr) {
delegate_->OnChlo(framer_->transport_version(), connection_id_, message);
}
found_chlo_ = true;
}
} // namespace
// static
bool ChloExtractor::Extract(const QuicEncryptedPacket& packet,
const ParsedQuicVersionVector& versions,
const QuicTagVector& create_session_tag_indicators,
Delegate* delegate) {
QuicFramer framer(versions, QuicTime::Zero(), Perspective::IS_SERVER);
ChloFramerVisitor visitor(&framer, create_session_tag_indicators, delegate);
framer.set_visitor(&visitor);
if (!framer.ProcessPacket(packet)) {
return false;
}
return visitor.found_chlo() || visitor.chlo_contains_tags();
}
} // namespace net
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