Move SrtpSession and tests to their own files.

webrtc/pc/srtpsession_unittest.cc

+/*
+ *  Copyright 2004 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.
+ */
+
+#include "webrtc/pc/srtpsession.h"
+
+#include <string>
+
+#include "webrtc/media/base/fakertp.h"
+#include "webrtc/pc/srtptestutil.h"
+#include "webrtc/rtc_base/gunit.h"
+#include "webrtc/rtc_base/sslstreamadapter.h"  // For rtc::SRTP_*
+
+namespace rtc {
+
+class SrtpSessionTest : public testing::Test {
+ protected:
+  virtual void SetUp() {
+    rtp_len_ = sizeof(kPcmuFrame);
+    rtcp_len_ = sizeof(kRtcpReport);
+    memcpy(rtp_packet_, kPcmuFrame, rtp_len_);
+    memcpy(rtcp_packet_, kRtcpReport, rtcp_len_);
+  }
+  void TestProtectRtp(const std::string& cs) {
+    int out_len = 0;
+    EXPECT_TRUE(
+        s1_.ProtectRtp(rtp_packet_, rtp_len_, sizeof(rtp_packet_), &out_len));
+    EXPECT_EQ(out_len, rtp_len_ + rtp_auth_tag_len(cs));
+    EXPECT_NE(0, memcmp(rtp_packet_, kPcmuFrame, rtp_len_));
+    rtp_len_ = out_len;
+  }
+  void TestProtectRtcp(const std::string& cs) {
+    int out_len = 0;
+    EXPECT_TRUE(s1_.ProtectRtcp(rtcp_packet_, rtcp_len_, sizeof(rtcp_packet_),
+                                &out_len));
+    EXPECT_EQ(out_len, rtcp_len_ + 4 + rtcp_auth_tag_len(cs));  // NOLINT
+    EXPECT_NE(0, memcmp(rtcp_packet_, kRtcpReport, rtcp_len_));
+    rtcp_len_ = out_len;
+  }
+  void TestUnprotectRtp(const std::string& cs) {
+    int out_len = 0, expected_len = sizeof(kPcmuFrame);
+    EXPECT_TRUE(s2_.UnprotectRtp(rtp_packet_, rtp_len_, &out_len));
+    EXPECT_EQ(expected_len, out_len);
+    EXPECT_EQ(0, memcmp(rtp_packet_, kPcmuFrame, out_len));
+  }
+  void TestUnprotectRtcp(const std::string& cs) {
+    int out_len = 0, expected_len = sizeof(kRtcpReport);
+    EXPECT_TRUE(s2_.UnprotectRtcp(rtcp_packet_, rtcp_len_, &out_len));
+    EXPECT_EQ(expected_len, out_len);
+    EXPECT_EQ(0, memcmp(rtcp_packet_, kRtcpReport, out_len));
+  }
+  cricket::SrtpSession s1_;
+  cricket::SrtpSession s2_;
+  char rtp_packet_[sizeof(kPcmuFrame) + 10];
+  char rtcp_packet_[sizeof(kRtcpReport) + 4 + 10];
+  int rtp_len_;
+  int rtcp_len_;
+};
+
+// Test that we can set up the session and keys properly.
+TEST_F(SrtpSessionTest, TestGoodSetup) {
+  EXPECT_TRUE(s1_.SetSend(SRTP_AES128_CM_SHA1_80, kTestKey1, kTestKeyLen));
+  EXPECT_TRUE(s2_.SetRecv(SRTP_AES128_CM_SHA1_80, kTestKey1, kTestKeyLen));
+}
+
+// Test that we can't change the keys once set.
+TEST_F(SrtpSessionTest, TestBadSetup) {
+  EXPECT_TRUE(s1_.SetSend(SRTP_AES128_CM_SHA1_80, kTestKey1, kTestKeyLen));
+  EXPECT_TRUE(s2_.SetRecv(SRTP_AES128_CM_SHA1_80, kTestKey1, kTestKeyLen));
+  EXPECT_FALSE(s1_.SetSend(SRTP_AES128_CM_SHA1_80, kTestKey2, kTestKeyLen));
+  EXPECT_FALSE(s2_.SetRecv(SRTP_AES128_CM_SHA1_80, kTestKey2, kTestKeyLen));
+}
+
+// Test that we fail keys of the wrong length.
+TEST_F(SrtpSessionTest, TestKeysTooShort) {
+  EXPECT_FALSE(s1_.SetSend(SRTP_AES128_CM_SHA1_80, kTestKey1, 1));
+  EXPECT_FALSE(s2_.SetRecv(SRTP_AES128_CM_SHA1_80, kTestKey1, 1));
+}
+
+// Test that we can encrypt and decrypt RTP/RTCP using AES_CM_128_HMAC_SHA1_80.
+TEST_F(SrtpSessionTest, TestProtect_AES_CM_128_HMAC_SHA1_80) {
+  EXPECT_TRUE(s1_.SetSend(SRTP_AES128_CM_SHA1_80, kTestKey1, kTestKeyLen));
+  EXPECT_TRUE(s2_.SetRecv(SRTP_AES128_CM_SHA1_80, kTestKey1, kTestKeyLen));
+  TestProtectRtp(CS_AES_CM_128_HMAC_SHA1_80);
+  TestProtectRtcp(CS_AES_CM_128_HMAC_SHA1_80);
+  TestUnprotectRtp(CS_AES_CM_128_HMAC_SHA1_80);
+  TestUnprotectRtcp(CS_AES_CM_128_HMAC_SHA1_80);
+}
+
+// Test that we can encrypt and decrypt RTP/RTCP using AES_CM_128_HMAC_SHA1_32.
+TEST_F(SrtpSessionTest, TestProtect_AES_CM_128_HMAC_SHA1_32) {
+  EXPECT_TRUE(s1_.SetSend(SRTP_AES128_CM_SHA1_32, kTestKey1, kTestKeyLen));
+  EXPECT_TRUE(s2_.SetRecv(SRTP_AES128_CM_SHA1_32, kTestKey1, kTestKeyLen));
+  TestProtectRtp(CS_AES_CM_128_HMAC_SHA1_32);
+  TestProtectRtcp(CS_AES_CM_128_HMAC_SHA1_32);
+  TestUnprotectRtp(CS_AES_CM_128_HMAC_SHA1_32);
+  TestUnprotectRtcp(CS_AES_CM_128_HMAC_SHA1_32);
+}
+
+TEST_F(SrtpSessionTest, TestGetSendStreamPacketIndex) {
+  EXPECT_TRUE(s1_.SetSend(SRTP_AES128_CM_SHA1_32, kTestKey1, kTestKeyLen));
+  int64_t index;
+  int out_len = 0;
+  EXPECT_TRUE(s1_.ProtectRtp(rtp_packet_, rtp_len_, sizeof(rtp_packet_),
+                             &out_len, &index));
+  // |index| will be shifted by 16.
+  int64_t be64_index = static_cast<int64_t>(NetworkToHost64(1 << 16));
+  EXPECT_EQ(be64_index, index);
+}
+
+// Test that we fail to unprotect if someone tampers with the RTP/RTCP paylaods.
+TEST_F(SrtpSessionTest, TestTamperReject) {
+  int out_len;
+  EXPECT_TRUE(s1_.SetSend(SRTP_AES128_CM_SHA1_80, kTestKey1, kTestKeyLen));
+  EXPECT_TRUE(s2_.SetRecv(SRTP_AES128_CM_SHA1_80, kTestKey1, kTestKeyLen));
+  TestProtectRtp(CS_AES_CM_128_HMAC_SHA1_80);
+  TestProtectRtcp(CS_AES_CM_128_HMAC_SHA1_80);
+  rtp_packet_[0] = 0x12;
+  rtcp_packet_[1] = 0x34;
+  EXPECT_FALSE(s2_.UnprotectRtp(rtp_packet_, rtp_len_, &out_len));
+  EXPECT_FALSE(s2_.UnprotectRtcp(rtcp_packet_, rtcp_len_, &out_len));
+}
+
+// Test that we fail to unprotect if the payloads are not authenticated.
+TEST_F(SrtpSessionTest, TestUnencryptReject) {
+  int out_len;
+  EXPECT_TRUE(s1_.SetSend(SRTP_AES128_CM_SHA1_80, kTestKey1, kTestKeyLen));
+  EXPECT_TRUE(s2_.SetRecv(SRTP_AES128_CM_SHA1_80, kTestKey1, kTestKeyLen));
+  EXPECT_FALSE(s2_.UnprotectRtp(rtp_packet_, rtp_len_, &out_len));
+  EXPECT_FALSE(s2_.UnprotectRtcp(rtcp_packet_, rtcp_len_, &out_len));
+}
+
+// Test that we fail when using buffers that are too small.
+TEST_F(SrtpSessionTest, TestBuffersTooSmall) {
+  int out_len;
+  EXPECT_TRUE(s1_.SetSend(SRTP_AES128_CM_SHA1_80, kTestKey1, kTestKeyLen));
+  EXPECT_FALSE(s1_.ProtectRtp(rtp_packet_, rtp_len_, sizeof(rtp_packet_) - 10,
+                              &out_len));
+  EXPECT_FALSE(s1_.ProtectRtcp(rtcp_packet_, rtcp_len_,
+                               sizeof(rtcp_packet_) - 14, &out_len));
+}
+
+TEST_F(SrtpSessionTest, TestReplay) {
+  static const uint16_t kMaxSeqnum = static_cast<uint16_t>(-1);
+  static const uint16_t seqnum_big = 62275;
+  static const uint16_t seqnum_small = 10;
+  static const uint16_t replay_window = 1024;
+  int out_len;
+
+  EXPECT_TRUE(s1_.SetSend(SRTP_AES128_CM_SHA1_80, kTestKey1, kTestKeyLen));
+  EXPECT_TRUE(s2_.SetRecv(SRTP_AES128_CM_SHA1_80, kTestKey1, kTestKeyLen));
+
+  // Initial sequence number.
+  SetBE16(reinterpret_cast<uint8_t*>(rtp_packet_) + 2, seqnum_big);
+  EXPECT_TRUE(
+      s1_.ProtectRtp(rtp_packet_, rtp_len_, sizeof(rtp_packet_), &out_len));
+
+  // Replay within the 1024 window should succeed.
+  SetBE16(reinterpret_cast<uint8_t*>(rtp_packet_) + 2,
+          seqnum_big - replay_window + 1);
+  EXPECT_TRUE(
+      s1_.ProtectRtp(rtp_packet_, rtp_len_, sizeof(rtp_packet_), &out_len));
+
+  // Replay out side of the 1024 window should fail.
+  SetBE16(reinterpret_cast<uint8_t*>(rtp_packet_) + 2,
+          seqnum_big - replay_window - 1);
+  EXPECT_FALSE(
+      s1_.ProtectRtp(rtp_packet_, rtp_len_, sizeof(rtp_packet_), &out_len));
+
+  // Increment sequence number to a small number.
+  SetBE16(reinterpret_cast<uint8_t*>(rtp_packet_) + 2, seqnum_small);
+  EXPECT_TRUE(
+      s1_.ProtectRtp(rtp_packet_, rtp_len_, sizeof(rtp_packet_), &out_len));
+
+  // Replay around 0 but out side of the 1024 window should fail.
+  SetBE16(reinterpret_cast<uint8_t*>(rtp_packet_) + 2,
+          kMaxSeqnum + seqnum_small - replay_window - 1);
+  EXPECT_FALSE(
+      s1_.ProtectRtp(rtp_packet_, rtp_len_, sizeof(rtp_packet_), &out_len));
+
+  // Replay around 0 but within the 1024 window should succeed.
+  for (uint16_t seqnum = 65000; seqnum < 65003; ++seqnum) {
+    SetBE16(reinterpret_cast<uint8_t*>(rtp_packet_) + 2, seqnum);
+    EXPECT_TRUE(
+        s1_.ProtectRtp(rtp_packet_, rtp_len_, sizeof(rtp_packet_), &out_len));
+  }
+
+  // Go back to normal sequence nubmer.
+  // NOTE: without the fix in libsrtp, this would fail. This is because
+  // without the fix, the loop above would keep incrementing local sequence
+  // number in libsrtp, eventually the new sequence number would go out side
+  // of the window.
+  SetBE16(reinterpret_cast<uint8_t*>(rtp_packet_) + 2, seqnum_small + 1);
+  EXPECT_TRUE(
+      s1_.ProtectRtp(rtp_packet_, rtp_len_, sizeof(rtp_packet_), &out_len));
+}
+
+}  // namespace rtc