gecko-dev/media/mtransport/mediapacket.cpp

143 строки
3.5 KiB
C++

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this file,
* You can obtain one at http://mozilla.org/MPL/2.0/. */
#include "mediapacket.h"
#include <cstring>
#include "ipc/IPCMessageUtils.h"
namespace mozilla {
MediaPacket::MediaPacket(const MediaPacket& orig)
: sdp_level_(orig.sdp_level_), type_(orig.type_) {
Copy(orig.data(), orig.len(), orig.capacity_);
}
void MediaPacket::Copy(const uint8_t* data, size_t len, size_t capacity) {
if (capacity < len) {
capacity = len;
}
data_.reset(new uint8_t[capacity]);
len_ = len;
capacity_ = capacity;
memcpy(data_.get(), data, len);
}
void MediaPacket::Serialize(IPC::Message* aMsg) const {
aMsg->WriteUInt32(len_);
aMsg->WriteUInt32(capacity_);
if (len_) {
aMsg->WriteBytes(data_.get(), len_);
}
aMsg->WriteUInt32(encrypted_len_);
if (encrypted_len_) {
aMsg->WriteBytes(encrypted_data_.get(), encrypted_len_);
}
aMsg->WriteInt32(sdp_level_.isSome() ? *sdp_level_ : -1);
aMsg->WriteInt32(type_);
}
bool MediaPacket::Deserialize(const IPC::Message* aMsg, PickleIterator* aIter) {
Reset();
uint32_t len;
if (!aMsg->ReadUInt32(aIter, &len)) {
return false;
}
uint32_t capacity;
if (!aMsg->ReadUInt32(aIter, &capacity)) {
return false;
}
if (len) {
MOZ_RELEASE_ASSERT(capacity >= len);
UniquePtr<uint8_t[]> data(new uint8_t[capacity]);
if (!aMsg->ReadBytesInto(aIter, data.get(), len)) {
return false;
}
data_ = std::move(data);
len_ = len;
capacity_ = capacity;
}
if (!aMsg->ReadUInt32(aIter, &len)) {
return false;
}
if (len) {
UniquePtr<uint8_t[]> data(new uint8_t[len]);
if (!aMsg->ReadBytesInto(aIter, data.get(), len)) {
return false;
}
encrypted_data_ = std::move(data);
encrypted_len_ = len;
}
int32_t sdp_level;
if (!aMsg->ReadInt32(aIter, &sdp_level)) {
return false;
}
if (sdp_level >= 0) {
sdp_level_ = Some(sdp_level);
}
int32_t type;
if (!aMsg->ReadInt32(aIter, &type)) {
return false;
}
type_ = static_cast<Type>(type);
return true;
}
static bool IsRtp(const uint8_t* data, size_t len) {
if (len < 2) return false;
// Check if this is a RTCP packet. Logic based on the types listed in
// media/webrtc/trunk/src/modules/rtp_rtcp/source/rtp_utility.cc
// Anything outside this range is RTP.
if ((data[1] < 192) || (data[1] > 207)) return true;
if (data[1] == 192) // FIR
return false;
if (data[1] == 193) // NACK, but could also be RTP. This makes us sad
return true; // but it's how webrtc.org behaves.
if (data[1] == 194) return true;
if (data[1] == 195) // IJ.
return false;
if ((data[1] > 195) && (data[1] < 200)) // the > 195 is redundant
return true;
if ((data[1] >= 200) && (data[1] <= 207)) // SR, RR, SDES, BYE,
return false; // APP, RTPFB, PSFB, XR
MOZ_ASSERT(false); // Not reached, belt and suspenders.
return true;
}
void MediaPacket::Categorize() {
SetType(MediaPacket::UNCLASSIFIED);
if (!data_ || len_ < 4) {
return;
}
if (data_[0] >= 20 && data_[0] <= 63) {
// DTLS per RFC 7983
SetType(MediaPacket::DTLS);
} else if (data_[0] > 127 && data_[0] < 192) {
// RTP/RTCP per RFC 7983
if (IsRtp(data_.get(), len_)) {
SetType(MediaPacket::SRTP);
} else {
SetType(MediaPacket::SRTCP);
}
}
}
} // namespace mozilla