1 /*
2 * Copyright (C) 2015 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17 #include <gtest/gtest.h>
18
19 #include <ifaddrs.h>
20
21 #include <dirent.h>
22 #include <fcntl.h>
23 #include <linux/if_packet.h>
24 #include <net/ethernet.h>
25 #include <net/if.h>
26 #include <netdb.h>
27 #include <netinet/in.h>
28 #include <sys/ioctl.h>
29
30 #include <algorithm>
31 #include <map>
32 #include <thread>
33 #include <vector>
34
TEST(ifaddrs,freeifaddrs_null)35 TEST(ifaddrs, freeifaddrs_null) {
36 freeifaddrs(nullptr);
37 }
38
39 // We can't statically say much about what network interfaces are available, but we can be pretty
40 // sure there's a loopback interface, and that it has IPv4, IPv6, and AF_PACKET entries.
TEST(ifaddrs,getifaddrs_lo)41 TEST(ifaddrs, getifaddrs_lo) {
42 ifaddrs* addrs = nullptr;
43
44 ASSERT_EQ(0, getifaddrs(&addrs));
45 ASSERT_TRUE(addrs != nullptr);
46
47 ifaddrs* lo_inet4 = nullptr;
48 ifaddrs* lo_inet6 = nullptr;
49 ifaddrs* lo_packet = nullptr;
50 for (ifaddrs* addr = addrs; addr != nullptr; addr = addr->ifa_next) {
51 if (addr->ifa_name && strcmp(addr->ifa_name, "lo") == 0) {
52 if (addr->ifa_addr && addr->ifa_addr->sa_family == AF_INET) lo_inet4 = addr;
53 else if (addr->ifa_addr && addr->ifa_addr->sa_family == AF_INET6) lo_inet6 = addr;
54 else if (addr->ifa_addr && addr->ifa_addr->sa_family == AF_PACKET) lo_packet = addr;
55 }
56 }
57
58 // Does the IPv4 entry look right?
59 ASSERT_TRUE(lo_inet4 != nullptr);
60 const sockaddr_in* sa_inet4 = reinterpret_cast<const sockaddr_in*>(lo_inet4->ifa_addr);
61 ASSERT_TRUE(ntohl(sa_inet4->sin_addr.s_addr) == INADDR_LOOPBACK);
62
63 // Does the IPv6 entry look right?
64 ASSERT_TRUE(lo_inet6 != nullptr);
65 const sockaddr_in6* sa_inet6 = reinterpret_cast<const sockaddr_in6*>(lo_inet6->ifa_addr);
66 ASSERT_TRUE(IN6_IS_ADDR_LOOPBACK(&sa_inet6->sin6_addr));
67
68 // Does the AF_PACKET entry look right?
69 ASSERT_TRUE(lo_packet != nullptr);
70 const sockaddr_ll* sa_ll = reinterpret_cast<const sockaddr_ll*>(lo_packet->ifa_addr);
71 ASSERT_EQ(6, sa_ll->sll_halen);
72
73 freeifaddrs(addrs);
74 }
75
76 // Check that getifaddrs sees the same list of interfaces as /sys/class/net.
TEST(ifaddrs,getifaddrs_interfaces)77 TEST(ifaddrs, getifaddrs_interfaces) {
78 std::vector<std::string> ifaddrs_socks;
79 {
80 ifaddrs* addrs;
81 ASSERT_EQ(0, getifaddrs(&addrs));
82
83 for (ifaddrs* addr = addrs; addr != nullptr; addr = addr->ifa_next) {
84 int family = addr->ifa_addr ? addr->ifa_addr->sa_family :
85 addr->ifa_broadaddr ? addr->ifa_broadaddr->sa_family :
86 AF_UNSPEC;
87
88 if (family == AF_PACKET || family == AF_UNSPEC) {
89 ifaddrs_socks.push_back(std::string(addr->ifa_name));
90 }
91 }
92
93 freeifaddrs(addrs);
94 }
95
96 std::vector<std::string> sys_class_net;
97 {
98 std::unique_ptr<DIR, decltype(&closedir)> d(opendir("/sys/class/net"), closedir);
99 ASSERT_TRUE(d != nullptr);
100 dirent* dir;
101 while ((dir = readdir(d.get())) != nullptr) {
102 if (dir->d_type == DT_LNK) {
103 sys_class_net.push_back(std::string(dir->d_name));
104 }
105 }
106 }
107
108 ASSERT_TRUE(std::is_permutation(ifaddrs_socks.begin(), ifaddrs_socks.end(),
109 sys_class_net.begin()));
110 }
111
CheckAddressIsInSet(const std::string & if_name,bool unicast,const std::set<in_addr_t> & addrs)112 static void CheckAddressIsInSet(const std::string& if_name, bool unicast,
113 const std::set<in_addr_t>& addrs) {
114 ifreq ifr;
115 memset(&ifr, 0, sizeof(ifr));
116 ifr.ifr_addr.sa_family = AF_INET;
117 if_name.copy(ifr.ifr_name, IFNAMSIZ - 1);
118
119 int fd = socket(AF_INET, SOCK_DGRAM, 0);
120 ASSERT_TRUE(fd != -1);
121
122 int request = SIOCGIFADDR;
123 if (!unicast) {
124 // For non-unicast, the specific ioctl to use depends on whether the IFF_BROADCAST flag is set.
125 ASSERT_EQ(0, ioctl(fd, SIOCGIFFLAGS, &ifr)) << if_name << ' ' << strerror(errno);
126 request = ((ifr.ifr_flags & IFF_BROADCAST) != 0) ? SIOCGIFBRDADDR : SIOCGIFDSTADDR;
127 }
128
129 ASSERT_EQ(0, ioctl(fd, request, &ifr)) << if_name << ' ' << strerror(errno);
130 close(fd);
131
132 sockaddr_in* sock = reinterpret_cast<sockaddr_in*>(&ifr.ifr_addr);
133 in_addr_t addr = sock->sin_addr.s_addr;
134
135 EXPECT_TRUE(addrs.find(addr) != addrs.end()) << if_name << ' ' << std::hex << ntohl(addr);
136 }
137
TEST(ifaddrs,getifaddrs_INET)138 TEST(ifaddrs, getifaddrs_INET) {
139 std::map<std::string, std::set<in_addr_t>> inet_addrs;
140 std::map<std::string, std::set<in_addr_t>> broad_addrs;
141
142 // Collect the IPv4 addresses for each interface.
143 ifaddrs* addrs;
144 ASSERT_EQ(0, getifaddrs(&addrs));
145 for (ifaddrs* addr = addrs; addr != nullptr; addr = addr->ifa_next) {
146 if (addr->ifa_name && addr->ifa_addr && addr->ifa_addr->sa_family == AF_INET) {
147 auto sock = reinterpret_cast<sockaddr_in*>(addr->ifa_addr);
148 inet_addrs[addr->ifa_name].insert(sock->sin_addr.s_addr);
149 }
150 if (addr->ifa_name && addr->ifa_broadaddr && addr->ifa_broadaddr->sa_family == AF_INET) {
151 auto sock = reinterpret_cast<sockaddr_in*>(addr->ifa_broadaddr);
152 broad_addrs[addr->ifa_name].insert(sock->sin_addr.s_addr);
153 }
154 }
155 freeifaddrs(addrs);
156
157 // Check that the addresses returned by the SIOCGIFADDR and SIOCGIFBRDADDR/SIOCGIFDSTADDR ioctls
158 // are in our collections.
159 for (const auto& it : inet_addrs) CheckAddressIsInSet(it.first, true, it.second);
160 for (const auto& it : broad_addrs) CheckAddressIsInSet(it.first, false, it.second);
161 }
162
print_sockaddr_ll(const char * what,const sockaddr * p)163 static void print_sockaddr_ll(const char* what, const sockaddr* p) {
164 const sockaddr_ll* s = reinterpret_cast<const sockaddr_ll*>(p);
165 printf("\t\t%s\t", what);
166 for (int i = 0; i < s->sll_halen; ++i) {
167 if (i > 0) printf(":");
168 printf("%02X", s->sll_addr[i]);
169 }
170 printf(" (%d bytes)\n", s->sll_halen);
171 }
172
print_sockaddr_inet(const char * what,const sockaddr * addr)173 static void print_sockaddr_inet(const char* what, const sockaddr* addr) {
174 char host[NI_MAXHOST];
175 int family = addr->sa_family;
176 int error = getnameinfo(addr,
177 (family == AF_INET) ? sizeof(sockaddr_in) : sizeof(sockaddr_in6),
178 host, NI_MAXHOST, nullptr, 0, NI_NUMERICHOST);
179 if (error != 0) {
180 printf("%d getnameinfo() failed: %s\n", family, gai_strerror(error));
181 strcpy(host, "???");
182 }
183 printf("\t\t%s: <%s>\n", what, host);
184 }
185
FamilyToName(int family)186 static const char* FamilyToName(int family) {
187 if (family == AF_INET) return "AF_INET";
188 if (family == AF_INET6) return "AF_INET6";
189 if (family == AF_PACKET) return "AF_PACKET";
190 if (family == AF_UNSPEC) return "AF_UNSPEC";
191 return "?";
192 }
193
FlagsToString(short flags)194 static std::string FlagsToString(short flags) {
195 std::string result;
196 if ((flags & IFF_UP) != 0) result += " UP";
197 if ((flags & IFF_BROADCAST) != 0) result += " BROADCAST";
198 if ((flags & IFF_DEBUG) != 0) result += " DEBUG";
199 if ((flags & IFF_LOOPBACK) != 0) result += " LOOPBACK";
200 if ((flags & IFF_POINTOPOINT) != 0) result += " POINTOPOINT";
201 if ((flags & IFF_NOTRAILERS) != 0) result += " NOTRAILERS";
202 if ((flags & IFF_RUNNING) != 0) result += " RUNNING";
203 if ((flags & IFF_NOARP) != 0) result += " NOARP";
204 if ((flags & IFF_PROMISC) != 0) result += " PROMISC";
205 if ((flags & IFF_ALLMULTI) != 0) result += " ALLMULTI";
206 if ((flags & IFF_MASTER) != 0) result += " MASTER";
207 if ((flags & IFF_SLAVE) != 0) result += " SLAVE";
208 if ((flags & IFF_MULTICAST) != 0) result += " MULTICAST";
209 if ((flags & IFF_PORTSEL) != 0) result += " PORTSEL";
210 if ((flags & IFF_AUTOMEDIA) != 0) result += " AUTOMEDIA";
211 if ((flags & IFF_DYNAMIC) != 0) result += " DYNAMIC";
212 #if defined(IFF_LOWER_UP)
213 if ((flags & IFF_LOWER_UP) != 0) result += " LOWER_UP";
214 #endif
215 #if defined(IFF_DORMANT)
216 if ((flags & IFF_DORMANT) != 0) result += " DORMANT";
217 #endif
218 #if defined(IFF_ECHO)
219 if ((flags & IFF_ECHO) != 0) result += " ECHO";
220 #endif
221 return result;
222 }
223
224 // Not really a test, but a useful debugging tool.
TEST(ifaddrs,dump)225 TEST(ifaddrs, dump) {
226 ifaddrs* addrs;
227 ASSERT_EQ(0, getifaddrs(&addrs));
228
229 for (ifaddrs* ifa = addrs; ifa != nullptr; ifa = ifa->ifa_next) {
230 int family = ifa->ifa_addr ? ifa->ifa_addr->sa_family :
231 ifa->ifa_broadaddr ? ifa->ifa_broadaddr->sa_family : AF_UNSPEC;
232
233 printf("\t%s\n"
234 "\t\t%s (%d) flags=%#x%s\n",
235 ifa->ifa_name, FamilyToName(family), family,
236 ifa->ifa_flags, FlagsToString(ifa->ifa_flags).c_str());
237
238 if (family == AF_PACKET) {
239 if (ifa->ifa_addr) print_sockaddr_ll("hwaddr", ifa->ifa_addr);
240 if (ifa->ifa_broadaddr) print_sockaddr_ll("hwbroad", ifa->ifa_addr);
241 } else if (family == AF_INET || family == AF_INET6) {
242 if (ifa->ifa_addr) print_sockaddr_inet("address", ifa->ifa_addr);
243 if (ifa->ifa_broadaddr && (ifa->ifa_flags & (IFF_BROADCAST | IFF_POINTOPOINT)) != 0) {
244 print_sockaddr_inet((ifa->ifa_flags & IFF_BROADCAST) ? "broadcast" : "destination",
245 ifa->ifa_broadaddr);
246 }
247 }
248
249 fflush(stdout);
250 }
251
252 freeifaddrs(addrs);
253 }
254
TEST(ifaddrs,inet6_scope_ids)255 TEST(ifaddrs, inet6_scope_ids) {
256 ifaddrs* addrs;
257 ASSERT_EQ(0, getifaddrs(&addrs));
258
259 for (ifaddrs* ifa = addrs; ifa != nullptr; ifa = ifa->ifa_next) {
260 if (ifa->ifa_addr && ifa->ifa_addr->sa_family == AF_INET6) {
261 sockaddr_in6* sa6 = reinterpret_cast<sockaddr_in6*>(ifa->ifa_addr);
262 // Any link-local IPv6 address should have a scope id. (http://b/27219454.)
263 // 0 isn't a valid interface index, so that would mean the scope id wasn't set.
264 if (IN6_IS_ADDR_LINKLOCAL(&sa6->sin6_addr) || IN6_IS_ADDR_MC_LINKLOCAL(&sa6->sin6_addr)) {
265 ASSERT_NE(sa6->sin6_scope_id, 0U);
266 }
267 }
268 }
269
270 freeifaddrs(addrs);
271 }
272
TEST(ifaddrs,kernel_bug_31038971)273 TEST(ifaddrs, kernel_bug_31038971) {
274 // Some kernels had a bug that would lead to an NLMSG_ERROR response,
275 // but bionic wasn't setting errno based on the value in the message.
276 // This is the test for the kernel bug, but on a device with a bad
277 // kernel this test was also useful for testing the bionic errno fix.
278 std::vector<std::thread*> threads;
279 for (size_t i = 0; i < 128; ++i) {
280 threads.push_back(new std::thread([]() {
281 ifaddrs* addrs = nullptr;
282 ASSERT_EQ(0, getifaddrs(&addrs)) << strerror(errno);
283 freeifaddrs(addrs);
284 }));
285 }
286 for (auto& t : threads) {
287 t->join();
288 delete t;
289 }
290 }
291
TEST(ifaddrs,errno_EMFILE)292 TEST(ifaddrs, errno_EMFILE) {
293 std::vector<int> fds;
294 while (true) {
295 int fd = open("/dev/null", O_RDONLY|O_CLOEXEC);
296 if (fd == -1) {
297 ASSERT_EQ(EMFILE, errno);
298 break;
299 }
300 fds.push_back(fd);
301 }
302
303 ifaddrs* addrs;
304 EXPECT_EQ(-1, getifaddrs(&addrs));
305 EXPECT_EQ(EMFILE, errno);
306
307 for (int fd : fds) close(fd);
308 }
309