Introduce TTL in QuicReceivedPacket.

net/tools/quic/quic_socket_utils.cc

 // 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.
 
 #include "net/tools/quic/quic_socket_utils.h"
 
 #include <errno.h>
 #include <linux/net_tstamp.h>
 #include <netinet/in.h>
 #include <string.h>
@@ skipping 55 matching lines @@
       if (cmsg->cmsg_type == SO_RXQ_OVFL) {
         *dropped_packets = *(reinterpret_cast<uint32_t*> CMSG_DATA(cmsg));
         return true;
       }
     }
   }
   return false;
 }
 
 // static
+bool QuicSocketUtils::GetTtlFromMsghdr(struct msghdr* hdr, int* ttl) {
+  if (hdr->msg_controllen > 0) {
+    struct cmsghdr* cmsg;
+    for (cmsg = CMSG_FIRSTHDR(hdr); cmsg != nullptr;
+         cmsg = CMSG_NXTHDR(hdr, cmsg)) {
+      if ((cmsg->cmsg_level == IPPROTO_IP && cmsg->cmsg_type == IP_TTL) ||
+          (cmsg->cmsg_level == IPPROTO_IPV6 &&
+           cmsg->cmsg_type == IPV6_HOPLIMIT)) {
+        *ttl = *(reinterpret_cast<int*>(CMSG_DATA(cmsg)));
+        return true;
+      }
+    }
+  }
+  return false;
+}
+
+// static
 int QuicSocketUtils::SetGetAddressInfo(int fd, int address_family) {
   int get_local_ip = 1;
   int rc = setsockopt(fd, IPPROTO_IP, IP_PKTINFO, &get_local_ip,
                       sizeof(get_local_ip));
   if (rc == 0 && address_family == AF_INET6) {
     rc = setsockopt(fd, IPPROTO_IPV6, IPV6_RECVPKTINFO, &get_local_ip,
                     sizeof(get_local_ip));
   }
   return rc;
 }
@@ skipping 208 matching lines @@
   rc = SetGetSoftwareReceiveTimestamp(fd);
   if (rc < 0) {
     LOG(WARNING) << "SO_TIMESTAMPING not supported; using fallback: "
                  << strerror(errno);
   }
 
   return fd;
 }
 
 }  // namespace net