Move talk/media to webrtc/media

talk/media/base/turnutils.cc

-/*
- * libjingle
- * Copyright 2016 Google Inc.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are met:
- *
- *  1. Redistributions of source code must retain the above copyright notice,
- *     this list of conditions and the following disclaimer.
- *  2. Redistributions in binary form must reproduce the above copyright notice,
- *     this list of conditions and the following disclaimer in the documentation
- *     and/or other materials provided with the distribution.
- *  3. The name of the author may not be used to endorse or promote products
- *     derived from this software without specific prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
- * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
- * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
- * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
- * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
- * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
- * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
- * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
- * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- */
-
-#include "talk/media/base/turnutils.h"
-
-#include "webrtc/base/byteorder.h"
-#include "webrtc/base/checks.h"
-#include "webrtc/p2p/base/stun.h"
-
-namespace cricket {
-
-namespace {
-
-const size_t kTurnChannelHeaderLength = 4;
-
-bool IsTurnChannelData(const uint8_t* data, size_t length) {
-  return length >= kTurnChannelHeaderLength && ((*data & 0xC0) == 0x40);
-}
-
-bool IsTurnSendIndicationPacket(const uint8_t* data, size_t length) {
-  if (length < kStunHeaderSize) {
-    return false;
-  }
-
-  uint16_t type = rtc::GetBE16(data);
-  return (type == TURN_SEND_INDICATION);
-}
-
-}  // namespace
-
-bool UnwrapTurnPacket(const uint8_t* packet,
-                      size_t packet_size,
-                      size_t* content_position,
-                      size_t* content_size) {
-  if (IsTurnChannelData(packet, packet_size)) {
-    // Turn Channel Message header format.
-    //   0                   1                   2                   3
-    //  0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
-    // +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
-    // |         Channel Number        |            Length             |
-    // +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
-    // |                                                               |
-    // /                       Application Data                        /
-    // /                                                               /
-    // +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
-    size_t length = rtc::GetBE16(&packet[2]);
-    if (length + kTurnChannelHeaderLength > packet_size) {
-      return false;
-    }
-
-    *content_position = kTurnChannelHeaderLength;
-    *content_size = length;
-    return true;
-  }
-
-  if (IsTurnSendIndicationPacket(packet, packet_size)) {
-    // Validate STUN message length.
-    const size_t stun_message_length = rtc::GetBE16(&packet[2]);
-    if (stun_message_length + kStunHeaderSize != packet_size) {
-      return false;
-    }
-
-    // First skip mandatory stun header which is of 20 bytes.
-    size_t pos = kStunHeaderSize;
-    // Loop through STUN attributes until we find STUN DATA attribute.
-    while (pos < packet_size) {
-      // Keep reading STUN attributes until we hit DATA attribute.
-      // Attribute will be a TLV structure.
-      // +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
-      // |         Type                  |            Length             |
-      // +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
-      // |                         Value (variable)                ....
-      // +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
-      // The value in the length field MUST contain the length of the Value
-      // part of the attribute, prior to padding, measured in bytes.  Since
-      // STUN aligns attributes on 32-bit boundaries, attributes whose content
-      // is not a multiple of 4 bytes are padded with 1, 2, or 3 bytes of
-      // padding so that its value contains a multiple of 4 bytes.  The
-      // padding bits are ignored, and may be any value.
-      uint16_t attr_type, attr_length;
-      const int kAttrHeaderLength = sizeof(attr_type) + sizeof(attr_length);
-
-      if (packet_size < pos + kAttrHeaderLength) {
-        return false;
-      }
-
-      // Getting attribute type and length.
-      attr_type = rtc::GetBE16(&packet[pos]);
-      attr_length = rtc::GetBE16(&packet[pos + sizeof(attr_type)]);
-
-      pos += kAttrHeaderLength;  // Skip STUN_DATA_ATTR header.
-
-      // Checking for bogus attribute length.
-      if (pos + attr_length > packet_size) {
-        return false;
-      }
-
-      if (attr_type == STUN_ATTR_DATA) {
-        *content_position = pos;
-        *content_size = attr_length;
-        return true;
-      }
-
-      pos += attr_length;
-      if ((attr_length % 4) != 0) {
-        pos += (4 - (attr_length % 4));
-      }
-    }
-
-    // There is no data attribute present in the message.
-    return false;
-  }
-
-  // This is not a TURN packet.
-  *content_position = 0;
-  *content_size = packet_size;
-  return true;
-}
-
-}  // namespace cricket