Fix oversized rtp extension parsing.

When size of individual one-byte extension span beyound extension block

BUG=chromium:645201
R=brandtr@webrtc.org

Review URL: https://codereview.webrtc.org/2327743003 .

Cr-Commit-Position: refs/heads/master@{#14183}
This commit is contained in:
Danil Chapovalov
2016-09-12 11:41:35 +02:00
parent 180e4525ca
commit a64a2fbf6d
2 changed files with 33 additions and 4 deletions

View File

@ -11,6 +11,7 @@
#include "webrtc/modules/rtp_rtcp/source/rtp_packet.h" #include "webrtc/modules/rtp_rtcp/source/rtp_packet.h"
#include <cstring> #include <cstring>
#include <utility>
#include "webrtc/base/checks.h" #include "webrtc/base/checks.h"
#include "webrtc/base/logging.h" #include "webrtc/base/logging.h"
@ -397,11 +398,16 @@ bool Packet::ParseBuffer(const uint8_t* buffer, size_t size) {
} }
uint8_t length = uint8_t length =
1 + (buffer[extension_offset + extensions_size_] & 0xf); 1 + (buffer[extension_offset + extensions_size_] & 0xf);
extensions_size_ += kOneByteHeaderSize; if (extensions_size_ + kOneByteHeaderSize + length >
if (num_extensions_ >= kMaxExtensionHeaders) { extensions_capacity) {
LOG(LS_WARNING) << "Too many extensions."; LOG(LS_WARNING) << "Oversized rtp header extension.";
return false; break;
} }
if (num_extensions_ >= kMaxExtensionHeaders) {
LOG(LS_WARNING) << "Too many rtp header extensions.";
break;
}
extensions_size_ += kOneByteHeaderSize;
extension_entries_[num_extensions_].type = extension_entries_[num_extensions_].type =
extensions_ ? extensions_->GetType(id) extensions_ ? extensions_->GetType(id)
: ExtensionManager::kInvalidType; : ExtensionManager::kInvalidType;

View File

@ -223,6 +223,29 @@ TEST(RtpPacketTest, ParseWithInvalidSizedExtension) {
ElementsAreArray(kPayload)); ElementsAreArray(kPayload));
} }
TEST(RtpPacketTest, ParseWithOverSizedExtension) {
// clang-format off
const uint8_t bad_packet[] = {
0x90, kPayloadType, 0x00, kSeqNum,
0x65, 0x43, 0x12, 0x78, // kTimestamp.
0x12, 0x34, 0x56, 0x78, // kSsrc.
0xbe, 0xde, 0x00, 0x01, // Extension of size 1x32bit word.
0x00, // Add a byte of padding.
0x12, // Extension id 1 size (2+1).
0xda, 0x1a // Only 2 bytes of extension payload.
};
// clang-format on
RtpPacketToSend::ExtensionManager extensions;
extensions.Register(TransmissionOffset::kId, 1);
RtpPacketReceived packet(&extensions);
// Parse should ignore bad extension and proceed.
EXPECT_TRUE(packet.Parse(bad_packet, sizeof(bad_packet)));
int32_t time_offset;
// But extracting extension should fail.
EXPECT_FALSE(packet.GetExtension<TransmissionOffset>(&time_offset));
}
TEST(RtpPacketTest, ParseWith2Extensions) { TEST(RtpPacketTest, ParseWith2Extensions) {
RtpPacketToSend::ExtensionManager extensions; RtpPacketToSend::ExtensionManager extensions;
extensions.Register(kRtpExtensionTransmissionTimeOffset, extensions.Register(kRtpExtensionTransmissionTimeOffset,