The Tor Browser: netwerk/sctp/src/ifaddrs_android.cpp@6474c204b198 (annotated)

netwerk/sctp/src/ifaddrs_android.cpp@6474c204b198 (annotated)

netwerk/sctp/src/ifaddrs_android.cpp

Wed, 31 Dec 2014 06:09:35 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Wed, 31 Dec 2014 06:09:35 +0100
changeset 0: 6474c204b198
permissions: -rw-r--r--

Cloned upstream origin tor-browser at tor-browser-31.3.0esr-4.5-1-build1
revision ID fc1c9ff7c1b2defdbc039f12214767608f46423f for hacking purpose.

 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
 /* vim: set ts=2 et sw=2 tw=80: */
 /*
  * Copyright (C) 2009 The Android Open Source Project
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
  *      http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
 #include "ifaddrs-android-ext.h"
 #include <stdlib.h>
 #include <string.h>
 #include "ScopedFd.h"
 #include "LocalArray.h"
 // Returns a pointer to the first byte in the address data (which is
 // stored in network byte order).
 uint8_t* sockaddrBytes(int family, sockaddr_storage* ss) {
     if (family == AF_INET) {
         sockaddr_in* ss4 = reinterpret_cast<sockaddr_in*>(ss);
         return reinterpret_cast<uint8_t*>(&ss4->sin_addr);
     } else if (family == AF_INET6) {
         sockaddr_in6* ss6 = reinterpret_cast<sockaddr_in6*>(ss);
         return reinterpret_cast<uint8_t*>(&ss6->sin6_addr);
     }
     return NULL;
 }
 // Sadly, we can't keep the interface index for portability with BSD.
 // We'll have to keep the name instead, and re-query the index when
 // we need it later.
 bool ifa_setNameAndFlagsByIndex(ifaddrs *self, int interfaceIndex) {
     // Get the name.
     char buf[IFNAMSIZ];
     char* name = if_indextoname(interfaceIndex, buf);
     if (name == NULL) {
         return false;
     }
     self->ifa_name = new char[strlen(name) + 1];
     strcpy(self->ifa_name, name);
     // Get the flags.
     ScopedFd fd(socket(AF_INET, SOCK_DGRAM, 0));
     if (fd.get() == -1) {
         return false;
     }
     ifreq ifr;
     memset(&ifr, 0, sizeof(ifr));
     strcpy(ifr.ifr_name, name);
     int rc = ioctl(fd.get(), SIOCGIFFLAGS, &ifr);
     if (rc == -1) {
         return false;
     }
     self->ifa_flags = ifr.ifr_flags;
     return true;
 }
 // Netlink gives us the address family in the header, and the
 // sockaddr_in or sockaddr_in6 bytes as the payload. We need to
 // stitch the two bits together into the sockaddr that's part of
 // our portable interface.
 void ifa_setAddress(ifaddrs *self, int family, void* data, size_t byteCount) {
     // Set the address proper...
     sockaddr_storage* ss = new sockaddr_storage;
     memset(ss, 0, sizeof(*ss));
     self->ifa_addr = reinterpret_cast<sockaddr*>(ss);
     ss->ss_family = family;
     uint8_t* dst = sockaddrBytes(family, ss);
     memcpy(dst, data, byteCount);
 }
 // Netlink gives us the prefix length as a bit count. We need to turn
 // that into a BSD-compatible netmask represented by a sockaddr*.
 void ifa_setNetmask(ifaddrs *self, int family, size_t prefixLength) {
     // ...and work out the netmask from the prefix length.
     sockaddr_storage* ss = new sockaddr_storage;
     memset(ss, 0, sizeof(*ss));
     self->ifa_netmask = reinterpret_cast<sockaddr*>(ss);
     ss->ss_family = family;
     uint8_t* dst = sockaddrBytes(family, ss);
     memset(dst, 0xff, prefixLength / 8);
     if ((prefixLength % 8) != 0) {
         dst[prefixLength/8] = (0xff << (8 - (prefixLength % 8)));
     }
 }
 // FIXME: use iovec instead.
 struct addrReq_struct {
     nlmsghdr netlinkHeader;
     ifaddrmsg msg;
 };
 inline bool sendNetlinkMessage(int fd, const void* data, size_t byteCount) {
     ssize_t sentByteCount = TEMP_FAILURE_RETRY(send(fd, data, byteCount, 0));
     return (sentByteCount == static_cast<ssize_t>(byteCount));
 }
 inline ssize_t recvNetlinkMessage(int fd, char* buf, size_t byteCount) {
     return TEMP_FAILURE_RETRY(recv(fd, buf, byteCount, 0));
 }
 // Source-compatible with the BSD function.
 int getifaddrs(ifaddrs** result)
 {
     // Simplify cleanup for callers.
     *result = NULL;
     // Create a netlink socket.
     ScopedFd fd(socket(AF_NETLINK, SOCK_DGRAM, NETLINK_ROUTE));
     if (fd.get() < 0) {
         return -1;
     }
     // Ask for the address information.
     addrReq_struct addrRequest;
     memset(&addrRequest, 0, sizeof(addrRequest));
     addrRequest.netlinkHeader.nlmsg_flags = NLM_F_REQUEST | NLM_F_MATCH;
     addrRequest.netlinkHeader.nlmsg_type = RTM_GETADDR;
     addrRequest.netlinkHeader.nlmsg_len = NLMSG_ALIGN(NLMSG_LENGTH(sizeof(addrRequest)));
     addrRequest.msg.ifa_family = AF_UNSPEC; // All families.
     addrRequest.msg.ifa_index = 0; // All interfaces.
     if (!sendNetlinkMessage(fd.get(), &addrRequest, addrRequest.netlinkHeader.nlmsg_len)) {
         return -1;
     }
     // Read the responses.
     LocalArray<0> buf(65536); // We don't necessarily have std::vector.
     ssize_t bytesRead;
     while ((bytesRead  = recvNetlinkMessage(fd.get(), &buf[0], buf.size())) > 0) {
         nlmsghdr* hdr = reinterpret_cast<nlmsghdr*>(&buf[0]);
         for (; NLMSG_OK(hdr, (size_t)bytesRead); hdr = NLMSG_NEXT(hdr, bytesRead)) {
             switch (hdr->nlmsg_type) {
             case NLMSG_DONE:
                 return 0;
             case NLMSG_ERROR:
                 return -1;
             case RTM_NEWADDR:
                 {
                     ifaddrmsg* address = reinterpret_cast<ifaddrmsg*>(NLMSG_DATA(hdr));
                     rtattr* rta = IFA_RTA(address);
                     size_t ifaPayloadLength = IFA_PAYLOAD(hdr);
                     while (RTA_OK(rta, ifaPayloadLength)) {
                         if (rta->rta_type == IFA_LOCAL) {
                             int family = address->ifa_family;
                             if (family == AF_INET || family == AF_INET6) {
                                 ifaddrs *next = *result;
                                 *result = new ifaddrs;
                                 memset(*result, 0, sizeof(ifaddrs));
                                 (*result)->ifa_next = next;
                                 if (!ifa_setNameAndFlagsByIndex(*result, address->ifa_index)) {
                                     return -1;
                                 }
                                 ifa_setAddress(*result, family, RTA_DATA(rta), RTA_PAYLOAD(rta));
                                 ifa_setNetmask(*result, family, address->ifa_prefixlen);
                             }
                         }
                         rta = RTA_NEXT(rta, ifaPayloadLength);
                     }
                 }
                 break;
             }
         }
     }
     // We only get here if recv fails before we see a NLMSG_DONE.
     return -1;
 }
 // Source-compatible with the BSD function.
 void freeifaddrs(ifaddrs* addresses) {
     ifaddrs* self = addresses;
     while (self != NULL) {
         delete[] self->ifa_name;
         delete self->ifa_addr;
         delete self->ifa_netmask;
         ifaddrs* next = self->ifa_next;
         delete self;
         self = next;
     }
 }

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netwerk/sctp/src/ifaddrs_android.cpp@6474c204b198 (annotated)

netwerk/sctp/src/ifaddrs_android.cpp