1 files changed, 128 insertions, 0 deletions
diff --git a/chromium/chrome/browser/net/probe_message.cc b/chromium/chrome/browser/net/probe_message.cc
new file mode 100644
index 00000000000..4ab7e3e28ee
--- /dev/null
+++ b/chromium/chrome/browser/net/probe_message.cc
@@ -0,0 +1,128 @@
+// Copyright 2013 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 "chrome/browser/net/probe_message.h"
+
+#include <stddef.h>
+
+#include <string>
+
+#include "base/logging.h"
+
+namespace chrome_browser_net {
+
+const uint32_t ProbeMessage::kVersion = 2;
+const uint32_t ProbeMessage::kMaxNumberProbePackets = 21;
+const uint32_t ProbeMessage::kMaxProbePacketBytes = 1500;
+// Maximum pacing interval is 300 seconds (for testing NAT binding).
+const uint32_t ProbeMessage::kMaxPacingIntervalMicros = 300000000;
+const char ProbeMessage::kEncodingString[] =
+    "T\xd3?\xa5h2\x9c\x8en\xf1Q6\xbc{\xc6-4\xfa$f\xb9[\xa6\xcd@6,\xdf\xb3i-\xe6"
+    "v\x9eV\x8dXd\xd9kE\xf6=\xbeO";
+
+ProbeMessage::ProbeMessage() {}
+
+bool ProbeMessage::ParseInput(const std::string& input,
+                              ProbePacket* probe_packet) const {
+  // Encode is used for decoding here.
+  std::string input_decoded = Encode(input);
+
+  bool parse_result = probe_packet->ParseFromString(input_decoded);
+  if (!parse_result) {
+    DVLOG(1) << "ProtoBuffer string parsing error. Input size:" << input.size();
+    return false;
+  }
+  const ProbePacket_Header& header = probe_packet->header();
+  DVLOG(2) << "version " << header.version() << " checksum "
+           << header.checksum() << " type " << header.type();
+  if (header.version() != kVersion) {
+    DVLOG(1) << "Bad version number: " << header.version()
+             << " expected: " << kVersion;
+    return false;
+  }
+
+  // Checksum is computed on padding only.
+  if (probe_packet->has_padding()) {
+    DVLOG(3) << "received padding: " << probe_packet->padding();
+    uint32_t computed_checksum = Checksum(probe_packet->padding());
+    if (computed_checksum != header.checksum()) {
+      DVLOG(1) << "Checksum mismatch.  Got: " << header.checksum()
+               << " expected: " << computed_checksum;
+      return false;
+    }
+  }
+
+  if (header.type() != ProbePacket_Type_HELLO_REPLY &&
+      header.type() != ProbePacket_Type_PROBE_REPLY) {
+    DVLOG(1) << "Received unknown packet type:" << header.type();
+    return false;
+  }
+  return true;
+}
+
+uint32_t ProbeMessage::Checksum(const std::string& str) const {
+  uint32_t ret = 0;
+  for (std::string::const_iterator i = str.begin(); i != str.end(); ++i) {
+    ret += static_cast<uint8_t>(*i);
+  }
+  return ret;
+}
+
+void ProbeMessage::GenerateProbeRequest(const ProbePacket_Token& token,
+                                        uint32_t group_id,
+                                        uint32_t probe_size,
+                                        uint32_t pacing_interval_micros,
+                                        uint32_t number_probe_packets,
+                                        ProbePacket* probe_packet) {
+  DCHECK_LE(number_probe_packets, kMaxNumberProbePackets);
+  DCHECK_LE(probe_size, kMaxProbePacketBytes);
+  DCHECK_LE(pacing_interval_micros, kMaxPacingIntervalMicros);
+
+  SetPacketHeader(ProbePacket_Type_PROBE_REQUEST, probe_packet);
+  *(probe_packet->mutable_token()) = token;
+  probe_packet->set_group_id(group_id);
+  probe_packet->set_probe_size_bytes(probe_size);
+  probe_packet->set_pacing_interval_micros(pacing_interval_micros);
+  probe_packet->set_number_probe_packets(number_probe_packets);
+
+  // Add padding to mitigate amplification attack.
+  std::string* padding = probe_packet->mutable_padding();
+  int padding_size = probe_size - probe_packet->ByteSize();
+  padding->append(std::string(std::max(0, padding_size), 0));
+  probe_packet->mutable_header()->set_checksum(Checksum(*padding));
+  DVLOG(3) << "Request size " << probe_packet->ByteSize() << " probe size "
+           << probe_size;
+  DCHECK_LE(probe_size, static_cast<uint32_t>(probe_packet->ByteSize()));
+}
+
+void ProbeMessage::SetPacketHeader(ProbePacket_Type packet_type,
+                                   ProbePacket* probe_packet) const {
+  ProbePacket_Header* header = probe_packet->mutable_header();
+  header->set_version(kVersion);
+  header->set_type(packet_type);
+}
+
+std::string ProbeMessage::Encode(const std::string& input) const {
+
+  std::string output(input.size(), 0);
+  int key_pos = 0;
+  // kEncodingString contains a ending '\0' character, excluded for encoding.
+  int key_size = sizeof(kEncodingString) - 1;
+  for (size_t i = 0; i < input.size(); ++i) {
+    output[i] = input[i] ^ kEncodingString[key_pos];
+    ++key_pos;
+    if (key_pos >= key_size)
+      key_pos = 0;
+  }
+  return output;
+}
+
+std::string ProbeMessage::MakeEncodedPacket(
+    const ProbePacket& probe_packet) const {
+  std::string output;
+  probe_packet.SerializeToString(&output);
+  return Encode(output);
+}
+
+}  // namespace chrome_browser_net