260 lines
10 KiB
C++
260 lines
10 KiB
C++
/*
|
|
* Copyright 2011 The WebRTC Project Authors. All rights reserved.
|
|
*
|
|
* Use of this source code is governed by a BSD-style license
|
|
* that can be found in the LICENSE file in the root of the source
|
|
* tree. An additional intellectual property rights grant can be found
|
|
* in the file PATENTS. All contributing project authors may
|
|
* be found in the AUTHORS file in the root of the source tree.
|
|
*/
|
|
|
|
#ifndef P2P_BASE_DTLS_TRANSPORT_H_
|
|
#define P2P_BASE_DTLS_TRANSPORT_H_
|
|
|
|
#include <memory>
|
|
#include <string>
|
|
#include <vector>
|
|
|
|
#include "api/crypto/crypto_options.h"
|
|
#include "p2p/base/dtls_transport_internal.h"
|
|
#include "p2p/base/ice_transport_internal.h"
|
|
#include "rtc_base/buffer.h"
|
|
#include "rtc_base/buffer_queue.h"
|
|
#include "rtc_base/constructor_magic.h"
|
|
#include "rtc_base/ssl_stream_adapter.h"
|
|
#include "rtc_base/stream.h"
|
|
#include "rtc_base/strings/string_builder.h"
|
|
#include "rtc_base/synchronization/sequence_checker.h"
|
|
#include "rtc_base/thread_checker.h"
|
|
|
|
namespace rtc {
|
|
class PacketTransportInternal;
|
|
}
|
|
|
|
namespace cricket {
|
|
|
|
// A bridge between a packet-oriented/transport-type interface on
|
|
// the bottom and a StreamInterface on the top.
|
|
class StreamInterfaceChannel : public rtc::StreamInterface {
|
|
public:
|
|
explicit StreamInterfaceChannel(IceTransportInternal* ice_transport);
|
|
|
|
// Push in a packet; this gets pulled out from Read().
|
|
bool OnPacketReceived(const char* data, size_t size);
|
|
|
|
// Implementations of StreamInterface
|
|
rtc::StreamState GetState() const override;
|
|
void Close() override;
|
|
rtc::StreamResult Read(void* buffer,
|
|
size_t buffer_len,
|
|
size_t* read,
|
|
int* error) override;
|
|
rtc::StreamResult Write(const void* data,
|
|
size_t data_len,
|
|
size_t* written,
|
|
int* error) override;
|
|
|
|
private:
|
|
webrtc::SequenceChecker sequence_checker_;
|
|
IceTransportInternal* const ice_transport_; // owned by DtlsTransport
|
|
rtc::StreamState state_ RTC_GUARDED_BY(sequence_checker_);
|
|
rtc::BufferQueue packets_ RTC_GUARDED_BY(sequence_checker_);
|
|
|
|
RTC_DISALLOW_COPY_AND_ASSIGN(StreamInterfaceChannel);
|
|
};
|
|
|
|
// This class provides a DTLS SSLStreamAdapter inside a TransportChannel-style
|
|
// packet-based interface, wrapping an existing TransportChannel instance
|
|
// (e.g a P2PTransportChannel)
|
|
// Here's the way this works:
|
|
//
|
|
// DtlsTransport {
|
|
// SSLStreamAdapter* dtls_ {
|
|
// StreamInterfaceChannel downward_ {
|
|
// IceTransportInternal* ice_transport_;
|
|
// }
|
|
// }
|
|
// }
|
|
//
|
|
// - Data which comes into DtlsTransport from the underlying
|
|
// ice_transport_ via OnReadPacket() is checked for whether it is DTLS
|
|
// or not, and if it is, is passed to DtlsTransport::HandleDtlsPacket,
|
|
// which pushes it into to downward_. dtls_ is listening for events on
|
|
// downward_, so it immediately calls downward_->Read().
|
|
//
|
|
// - Data written to DtlsTransport is passed either to downward_ or directly
|
|
// to ice_transport_, depending on whether DTLS is negotiated and whether
|
|
// the flags include PF_SRTP_BYPASS
|
|
//
|
|
// - The SSLStreamAdapter writes to downward_->Write() which translates it
|
|
// into packet writes on ice_transport_.
|
|
//
|
|
// This class is not thread safe; all methods must be called on the same thread
|
|
// as the constructor.
|
|
class DtlsTransport : public DtlsTransportInternal {
|
|
public:
|
|
// |ice_transport| is the ICE transport this DTLS transport is wrapping. It
|
|
// must outlive this DTLS transport.
|
|
//
|
|
// |crypto_options| are the options used for the DTLS handshake. This affects
|
|
// whether GCM crypto suites are negotiated.
|
|
//
|
|
// |event_log| is an optional RtcEventLog for logging state changes. It should
|
|
// outlive the DtlsTransport.
|
|
explicit DtlsTransport(IceTransportInternal* ice_transport,
|
|
const webrtc::CryptoOptions& crypto_options,
|
|
webrtc::RtcEventLog* event_log);
|
|
|
|
~DtlsTransport() override;
|
|
|
|
const webrtc::CryptoOptions& crypto_options() const override;
|
|
DtlsTransportState dtls_state() const override;
|
|
const std::string& transport_name() const override;
|
|
int component() const override;
|
|
|
|
// DTLS is active if a local certificate was set. Otherwise this acts in a
|
|
// "passthrough" mode, sending packets directly through the underlying ICE
|
|
// transport.
|
|
// TODO(deadbeef): Remove this weirdness, and handle it in the upper layers.
|
|
bool IsDtlsActive() const override;
|
|
|
|
// SetLocalCertificate is what makes DTLS active. It must be called before
|
|
// SetRemoteFinterprint.
|
|
// TODO(deadbeef): Once DtlsTransport no longer has the concept of being
|
|
// "active" or not (acting as a passthrough if not active), just require this
|
|
// certificate on construction or "Start".
|
|
bool SetLocalCertificate(
|
|
const rtc::scoped_refptr<rtc::RTCCertificate>& certificate) override;
|
|
rtc::scoped_refptr<rtc::RTCCertificate> GetLocalCertificate() const override;
|
|
|
|
// SetRemoteFingerprint must be called after SetLocalCertificate, and any
|
|
// other methods like SetDtlsRole. It's what triggers the actual DTLS setup.
|
|
// TODO(deadbeef): Rename to "Start" like in ORTC?
|
|
bool SetRemoteFingerprint(const std::string& digest_alg,
|
|
const uint8_t* digest,
|
|
size_t digest_len) override;
|
|
|
|
// Called to send a packet (via DTLS, if turned on).
|
|
int SendPacket(const char* data,
|
|
size_t size,
|
|
const rtc::PacketOptions& options,
|
|
int flags) override;
|
|
|
|
bool GetOption(rtc::Socket::Option opt, int* value) override;
|
|
|
|
bool SetSslMaxProtocolVersion(rtc::SSLProtocolVersion version) override;
|
|
|
|
// Find out which TLS version was negotiated
|
|
bool GetSslVersionBytes(int* version) const override;
|
|
// Find out which DTLS-SRTP cipher was negotiated
|
|
bool GetSrtpCryptoSuite(int* cipher) override;
|
|
|
|
bool GetDtlsRole(rtc::SSLRole* role) const override;
|
|
bool SetDtlsRole(rtc::SSLRole role) override;
|
|
|
|
// Find out which DTLS cipher was negotiated
|
|
bool GetSslCipherSuite(int* cipher) override;
|
|
|
|
// Once DTLS has been established, this method retrieves the certificate
|
|
// chain in use by the remote peer, for use in external identity
|
|
// verification.
|
|
std::unique_ptr<rtc::SSLCertChain> GetRemoteSSLCertChain() const override;
|
|
|
|
// Once DTLS has established (i.e., this ice_transport is writable), this
|
|
// method extracts the keys negotiated during the DTLS handshake, for use in
|
|
// external encryption. DTLS-SRTP uses this to extract the needed SRTP keys.
|
|
// See the SSLStreamAdapter documentation for info on the specific parameters.
|
|
bool ExportKeyingMaterial(const std::string& label,
|
|
const uint8_t* context,
|
|
size_t context_len,
|
|
bool use_context,
|
|
uint8_t* result,
|
|
size_t result_len) override;
|
|
|
|
IceTransportInternal* ice_transport() override;
|
|
|
|
// For informational purposes. Tells if the DTLS handshake has finished.
|
|
// This may be true even if writable() is false, if the remote fingerprint
|
|
// has not yet been verified.
|
|
bool IsDtlsConnected();
|
|
|
|
bool receiving() const override;
|
|
bool writable() const override;
|
|
|
|
int GetError() override;
|
|
|
|
absl::optional<rtc::NetworkRoute> network_route() const override;
|
|
|
|
int SetOption(rtc::Socket::Option opt, int value) override;
|
|
|
|
std::string ToString() const {
|
|
const absl::string_view RECEIVING_ABBREV[2] = {"_", "R"};
|
|
const absl::string_view WRITABLE_ABBREV[2] = {"_", "W"};
|
|
rtc::StringBuilder sb;
|
|
sb << "DtlsTransport[" << transport_name_ << "|" << component_ << "|"
|
|
<< RECEIVING_ABBREV[receiving()] << WRITABLE_ABBREV[writable()] << "]";
|
|
return sb.Release();
|
|
}
|
|
|
|
private:
|
|
void ConnectToIceTransport();
|
|
|
|
void OnWritableState(rtc::PacketTransportInternal* transport);
|
|
void OnReadPacket(rtc::PacketTransportInternal* transport,
|
|
const char* data,
|
|
size_t size,
|
|
const int64_t& packet_time_us,
|
|
int flags);
|
|
void OnSentPacket(rtc::PacketTransportInternal* transport,
|
|
const rtc::SentPacket& sent_packet);
|
|
void OnReadyToSend(rtc::PacketTransportInternal* transport);
|
|
void OnReceivingState(rtc::PacketTransportInternal* transport);
|
|
void OnDtlsEvent(rtc::StreamInterface* stream_, int sig, int err);
|
|
void OnNetworkRouteChanged(absl::optional<rtc::NetworkRoute> network_route);
|
|
bool SetupDtls();
|
|
void MaybeStartDtls();
|
|
bool HandleDtlsPacket(const char* data, size_t size);
|
|
void OnDtlsHandshakeError(rtc::SSLHandshakeError error);
|
|
void ConfigureHandshakeTimeout();
|
|
|
|
void set_receiving(bool receiving);
|
|
void set_writable(bool writable);
|
|
// Sets the DTLS state, signaling if necessary.
|
|
void set_dtls_state(DtlsTransportState state);
|
|
|
|
rtc::ThreadChecker thread_checker_;
|
|
|
|
std::string transport_name_;
|
|
int component_;
|
|
DtlsTransportState dtls_state_ = DTLS_TRANSPORT_NEW;
|
|
// Underlying ice_transport, not owned by this class.
|
|
IceTransportInternal* ice_transport_;
|
|
std::unique_ptr<rtc::SSLStreamAdapter> dtls_; // The DTLS stream
|
|
StreamInterfaceChannel*
|
|
downward_; // Wrapper for ice_transport_, owned by dtls_.
|
|
std::vector<int> srtp_ciphers_; // SRTP ciphers to use with DTLS.
|
|
bool dtls_active_ = false;
|
|
rtc::scoped_refptr<rtc::RTCCertificate> local_certificate_;
|
|
absl::optional<rtc::SSLRole> dtls_role_;
|
|
rtc::SSLProtocolVersion ssl_max_version_;
|
|
webrtc::CryptoOptions crypto_options_;
|
|
rtc::Buffer remote_fingerprint_value_;
|
|
std::string remote_fingerprint_algorithm_;
|
|
|
|
// Cached DTLS ClientHello packet that was received before we started the
|
|
// DTLS handshake. This could happen if the hello was received before the
|
|
// ice transport became writable, or before a remote fingerprint was received.
|
|
rtc::Buffer cached_client_hello_;
|
|
|
|
bool receiving_ = false;
|
|
bool writable_ = false;
|
|
|
|
webrtc::RtcEventLog* const event_log_;
|
|
|
|
RTC_DISALLOW_COPY_AND_ASSIGN(DtlsTransport);
|
|
};
|
|
|
|
} // namespace cricket
|
|
|
|
#endif // P2P_BASE_DTLS_TRANSPORT_H_
|