Introduce TTL in QuicReceivedPacket.

net/tools/quic/quic_socket_utils.h

 // Copyright (c) 2012 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.
 //
 // Some socket related helper methods for quic.
 
 #ifndef NET_TOOLS_QUIC_QUIC_SOCKET_UTILS_H_
 #define NET_TOOLS_QUIC_QUIC_SOCKET_UTILS_H_
 
 #include <netinet/in.h>
@@ skipping 20 matching lines @@
   // Deprecated; serves only as padding.
   struct timespec hwtimetrans;
   // The raw hardware timestamp.
   struct timespec hwtimeraw;
 };
 
 class QuicSocketUtils {
  public:
   // The first integer is for overflow. The in6_pktinfo is the larger of the
   // address structures present. LinuxTimestamping is present for socket
-  // timestamping.
+  // timestamping.  The subsequent int is for ttl.
   // The final int is a sentinel so the msg_controllen feedback
   // can be used to detect larger control messages than there is space for.
   static const int kSpaceForCmsg =
       CMSG_SPACE(CMSG_LEN(sizeof(int)) + CMSG_LEN(sizeof(in6_pktinfo)) +
                  CMSG_LEN(sizeof(LinuxTimestamping)) +
+                 CMSG_LEN(sizeof(int)) +
                  CMSG_LEN(sizeof(int)));
 
   // Fills in |address| if |hdr| contains IP_PKTINFO or IPV6_PKTINFO. Fills in
   // |timestamp| if |hdr| contains |SO_TIMESTAMPING|. |address| and |timestamp|
   // must not be null.
   static void GetAddressAndTimestampFromMsghdr(struct msghdr* hdr,
                                                IPAddress* address,
                                                QuicWallTime* walltimestamp);
 
   // If the msghdr contains an SO_RXQ_OVFL entry, this will set dropped_packets
   // to the correct value and return true. Otherwise it will return false.
   static bool GetOverflowFromMsghdr(struct msghdr* hdr,
                                     QuicPacketCount* dropped_packets);
 
+  // If the msghdr contains an IP_TTL entry, this will set ttl to the correct
+  // value and return true. Otherwise it will return false.
+  static bool GetTtlFromMsghdr(struct msghdr* hdr, int* ttl);
+
   // Sets either IP_PKTINFO or IPV6_PKTINFO on the socket, based on
   // address_family.  Returns the return code from setsockopt.
   static int SetGetAddressInfo(int fd, int address_family);
 
   // Sets SO_TIMESTAMPING on the socket for software receive timestamping.
   // Returns the return code from setsockopt.
   static int SetGetSoftwareReceiveTimestamp(int fd);
 
   // Sets the send buffer size to |size| and returns false if it fails.
   static bool SetSendBufferSize(int fd, size_t size);
@@ skipping 44 matching lines @@
   static int CreateUDPSocket(const IPEndPoint& address,
                              bool* overflow_supported);
 
  private:
   DISALLOW_COPY_AND_ASSIGN(QuicSocketUtils);
 };
 
 }  // namespace net
 
 #endif  // NET_TOOLS_QUIC_QUIC_SOCKET_UTILS_H_