1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/netwerk/sctp/src/ifaddrs_android.cpp Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,189 @@
1.4 +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
1.5 +/* vim: set ts=2 et sw=2 tw=80: */
1.6 +/*
1.7 + * Copyright (C) 2009 The Android Open Source Project
1.8 + *
1.9 + * Licensed under the Apache License, Version 2.0 (the "License");
1.10 + * you may not use this file except in compliance with the License.
1.11 + * You may obtain a copy of the License at
1.12 + *
1.13 + * http://www.apache.org/licenses/LICENSE-2.0
1.14 + *
1.15 + * Unless required by applicable law or agreed to in writing, software
1.16 + * distributed under the License is distributed on an "AS IS" BASIS,
1.17 + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
1.18 + * See the License for the specific language governing permissions and
1.19 + * limitations under the License.
1.20 + */
1.21 +
1.22 +#include "ifaddrs-android-ext.h"
1.23 +
1.24 +#include <stdlib.h>
1.25 +#include <string.h>
1.26 +#include "ScopedFd.h"
1.27 +#include "LocalArray.h"
1.28 +
1.29 +// Returns a pointer to the first byte in the address data (which is
1.30 +// stored in network byte order).
1.31 +uint8_t* sockaddrBytes(int family, sockaddr_storage* ss) {
1.32 + if (family == AF_INET) {
1.33 + sockaddr_in* ss4 = reinterpret_cast<sockaddr_in*>(ss);
1.34 + return reinterpret_cast<uint8_t*>(&ss4->sin_addr);
1.35 + } else if (family == AF_INET6) {
1.36 + sockaddr_in6* ss6 = reinterpret_cast<sockaddr_in6*>(ss);
1.37 + return reinterpret_cast<uint8_t*>(&ss6->sin6_addr);
1.38 + }
1.39 + return NULL;
1.40 +}
1.41 +
1.42 +// Sadly, we can't keep the interface index for portability with BSD.
1.43 +// We'll have to keep the name instead, and re-query the index when
1.44 +// we need it later.
1.45 +bool ifa_setNameAndFlagsByIndex(ifaddrs *self, int interfaceIndex) {
1.46 + // Get the name.
1.47 + char buf[IFNAMSIZ];
1.48 + char* name = if_indextoname(interfaceIndex, buf);
1.49 + if (name == NULL) {
1.50 + return false;
1.51 + }
1.52 + self->ifa_name = new char[strlen(name) + 1];
1.53 + strcpy(self->ifa_name, name);
1.54 +
1.55 + // Get the flags.
1.56 + ScopedFd fd(socket(AF_INET, SOCK_DGRAM, 0));
1.57 + if (fd.get() == -1) {
1.58 + return false;
1.59 + }
1.60 + ifreq ifr;
1.61 + memset(&ifr, 0, sizeof(ifr));
1.62 + strcpy(ifr.ifr_name, name);
1.63 + int rc = ioctl(fd.get(), SIOCGIFFLAGS, &ifr);
1.64 + if (rc == -1) {
1.65 + return false;
1.66 + }
1.67 + self->ifa_flags = ifr.ifr_flags;
1.68 + return true;
1.69 +}
1.70 +
1.71 +// Netlink gives us the address family in the header, and the
1.72 +// sockaddr_in or sockaddr_in6 bytes as the payload. We need to
1.73 +// stitch the two bits together into the sockaddr that's part of
1.74 +// our portable interface.
1.75 +void ifa_setAddress(ifaddrs *self, int family, void* data, size_t byteCount) {
1.76 + // Set the address proper...
1.77 + sockaddr_storage* ss = new sockaddr_storage;
1.78 + memset(ss, 0, sizeof(*ss));
1.79 + self->ifa_addr = reinterpret_cast<sockaddr*>(ss);
1.80 + ss->ss_family = family;
1.81 + uint8_t* dst = sockaddrBytes(family, ss);
1.82 + memcpy(dst, data, byteCount);
1.83 +}
1.84 +
1.85 +// Netlink gives us the prefix length as a bit count. We need to turn
1.86 +// that into a BSD-compatible netmask represented by a sockaddr*.
1.87 +void ifa_setNetmask(ifaddrs *self, int family, size_t prefixLength) {
1.88 + // ...and work out the netmask from the prefix length.
1.89 + sockaddr_storage* ss = new sockaddr_storage;
1.90 + memset(ss, 0, sizeof(*ss));
1.91 + self->ifa_netmask = reinterpret_cast<sockaddr*>(ss);
1.92 + ss->ss_family = family;
1.93 + uint8_t* dst = sockaddrBytes(family, ss);
1.94 + memset(dst, 0xff, prefixLength / 8);
1.95 + if ((prefixLength % 8) != 0) {
1.96 + dst[prefixLength/8] = (0xff << (8 - (prefixLength % 8)));
1.97 + }
1.98 +}
1.99 +
1.100 +// FIXME: use iovec instead.
1.101 +struct addrReq_struct {
1.102 + nlmsghdr netlinkHeader;
1.103 + ifaddrmsg msg;
1.104 +};
1.105 +
1.106 +inline bool sendNetlinkMessage(int fd, const void* data, size_t byteCount) {
1.107 + ssize_t sentByteCount = TEMP_FAILURE_RETRY(send(fd, data, byteCount, 0));
1.108 + return (sentByteCount == static_cast<ssize_t>(byteCount));
1.109 +}
1.110 +
1.111 +inline ssize_t recvNetlinkMessage(int fd, char* buf, size_t byteCount) {
1.112 + return TEMP_FAILURE_RETRY(recv(fd, buf, byteCount, 0));
1.113 +}
1.114 +
1.115 +// Source-compatible with the BSD function.
1.116 +int getifaddrs(ifaddrs** result)
1.117 +{
1.118 + // Simplify cleanup for callers.
1.119 + *result = NULL;
1.120 +
1.121 + // Create a netlink socket.
1.122 + ScopedFd fd(socket(AF_NETLINK, SOCK_DGRAM, NETLINK_ROUTE));
1.123 + if (fd.get() < 0) {
1.124 + return -1;
1.125 + }
1.126 +
1.127 + // Ask for the address information.
1.128 + addrReq_struct addrRequest;
1.129 + memset(&addrRequest, 0, sizeof(addrRequest));
1.130 + addrRequest.netlinkHeader.nlmsg_flags = NLM_F_REQUEST | NLM_F_MATCH;
1.131 + addrRequest.netlinkHeader.nlmsg_type = RTM_GETADDR;
1.132 + addrRequest.netlinkHeader.nlmsg_len = NLMSG_ALIGN(NLMSG_LENGTH(sizeof(addrRequest)));
1.133 + addrRequest.msg.ifa_family = AF_UNSPEC; // All families.
1.134 + addrRequest.msg.ifa_index = 0; // All interfaces.
1.135 + if (!sendNetlinkMessage(fd.get(), &addrRequest, addrRequest.netlinkHeader.nlmsg_len)) {
1.136 + return -1;
1.137 + }
1.138 +
1.139 + // Read the responses.
1.140 + LocalArray<0> buf(65536); // We don't necessarily have std::vector.
1.141 + ssize_t bytesRead;
1.142 + while ((bytesRead = recvNetlinkMessage(fd.get(), &buf[0], buf.size())) > 0) {
1.143 + nlmsghdr* hdr = reinterpret_cast<nlmsghdr*>(&buf[0]);
1.144 + for (; NLMSG_OK(hdr, (size_t)bytesRead); hdr = NLMSG_NEXT(hdr, bytesRead)) {
1.145 + switch (hdr->nlmsg_type) {
1.146 + case NLMSG_DONE:
1.147 + return 0;
1.148 + case NLMSG_ERROR:
1.149 + return -1;
1.150 + case RTM_NEWADDR:
1.151 + {
1.152 + ifaddrmsg* address = reinterpret_cast<ifaddrmsg*>(NLMSG_DATA(hdr));
1.153 + rtattr* rta = IFA_RTA(address);
1.154 + size_t ifaPayloadLength = IFA_PAYLOAD(hdr);
1.155 + while (RTA_OK(rta, ifaPayloadLength)) {
1.156 + if (rta->rta_type == IFA_LOCAL) {
1.157 + int family = address->ifa_family;
1.158 + if (family == AF_INET || family == AF_INET6) {
1.159 + ifaddrs *next = *result;
1.160 + *result = new ifaddrs;
1.161 + memset(*result, 0, sizeof(ifaddrs));
1.162 + (*result)->ifa_next = next;
1.163 + if (!ifa_setNameAndFlagsByIndex(*result, address->ifa_index)) {
1.164 + return -1;
1.165 + }
1.166 + ifa_setAddress(*result, family, RTA_DATA(rta), RTA_PAYLOAD(rta));
1.167 + ifa_setNetmask(*result, family, address->ifa_prefixlen);
1.168 + }
1.169 + }
1.170 + rta = RTA_NEXT(rta, ifaPayloadLength);
1.171 + }
1.172 + }
1.173 + break;
1.174 + }
1.175 + }
1.176 + }
1.177 + // We only get here if recv fails before we see a NLMSG_DONE.
1.178 + return -1;
1.179 +}
1.180 +
1.181 +// Source-compatible with the BSD function.
1.182 +void freeifaddrs(ifaddrs* addresses) {
1.183 + ifaddrs* self = addresses;
1.184 + while (self != NULL) {
1.185 + delete[] self->ifa_name;
1.186 + delete self->ifa_addr;
1.187 + delete self->ifa_netmask;
1.188 + ifaddrs* next = self->ifa_next;
1.189 + delete self;
1.190 + self = next;
1.191 + }
1.192 +}
