1 /* Test basic nss_dns functionality with multiple threads.
2 Copyright (C) 2016-2023 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
4
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
9
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
14
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, see
17 <https://www.gnu.org/licenses/>. */
18
19 /* Unlike tst-resolv-basic, this test does not overwrite the _res
20 structure and relies on namespaces to achieve the redirection to
21 the test servers with a custom /etc/resolv.conf file. */
22
23 #include <dlfcn.h>
24 #include <errno.h>
25 #include <gnu/lib-names.h>
26 #include <netdb.h>
27 #include <resolv/resolv-internal.h>
28 #include <resolv/resolv_context.h>
29 #include <stdio.h>
30 #include <stdlib.h>
31 #include <string.h>
32 #include <support/check.h>
33 #include <support/namespace.h>
34 #include <support/resolv_test.h>
35 #include <support/support.h>
36 #include <support/temp_file.h>
37 #include <support/test-driver.h>
38 #include <support/xthread.h>
39 #include <support/xunistd.h>
40
41 /* Each client thread sends this many queries. */
42 enum { queries_per_thread = 500 };
43
44 /* Return a small positive number identifying this thread. */
45 static int
46 get_thread_number (void)
47 {
48 static int __thread local;
49 if (local != 0)
50 return local;
51 static int global = 1;
52 local = __atomic_fetch_add (&global, 1, __ATOMIC_RELAXED);
53 return local;
54 }
55
56 static void
57 response (const struct resolv_response_context *ctx,
58 struct resolv_response_builder *b,
59 const char *qname, uint16_t qclass, uint16_t qtype)
60 {
61 TEST_VERIFY_EXIT (qname != NULL);
62
63 int counter = 0;
64 int thread = 0;
65 int dummy = 0;
66 TEST_VERIFY (sscanf (qname, "counter%d.thread%d.example.com%n",
67 &counter, &thread, &dummy) == 2);
68 TEST_VERIFY (dummy > 0);
69
70 struct resolv_response_flags flags = { 0 };
71 resolv_response_init (b, flags);
72 resolv_response_add_question (b, qname, qclass, qtype);
73
74 resolv_response_section (b, ns_s_an);
75 resolv_response_open_record (b, qname, qclass, qtype, 0);
76 switch (qtype)
77 {
78 case T_A:
79 {
80 char ipv4[4] = {10, 0, counter, thread};
81 resolv_response_add_data (b, &ipv4, sizeof (ipv4));
82 }
83 break;
84 case T_AAAA:
85 {
86 char ipv6[16]
87 = {0x20, 0x01, 0xd, 0xb8, 0, 0, 0, 0, 0, 0, 0,
88 counter, 0, thread, 0, 0};
89 resolv_response_add_data (b, &ipv6, sizeof (ipv6));
90 }
91 break;
92 default:
93 support_record_failure ();
94 printf ("error: unexpected QTYPE: %s/%u/%u\n",
95 qname, qclass, qtype);
96 }
97 resolv_response_close_record (b);
98 }
99
100 /* Check that the resolver configuration for this thread has an
101 extended resolver configuration. */
102 static void
103 check_have_conf (void)
104 {
105 struct resolv_context *ctx = __resolv_context_get ();
106 TEST_VERIFY_EXIT (ctx != NULL);
107 TEST_VERIFY (ctx->conf != NULL);
108 __resolv_context_put (ctx);
109 }
110
111 /* Verify that E matches the expected response for FAMILY and
112 COUNTER. */
113 static void
114 check_hostent (const char *caller, const char *function, const char *qname,
115 int ret, struct hostent *e, int family, int counter)
116 {
117 if (ret != 0)
118 {
119 errno = ret;
120 support_record_failure ();
121 printf ("error: %s: %s for %s failed: %m\n", caller, function, qname);
122 return;
123 }
124
125 TEST_VERIFY_EXIT (e != NULL);
126 TEST_VERIFY (strcmp (qname, e->h_name) == 0);
127 TEST_VERIFY (e->h_addrtype == family);
128 TEST_VERIFY_EXIT (e->h_addr_list[0] != NULL);
129 TEST_VERIFY (e->h_addr_list[1] == NULL);
130 switch (family)
131 {
132 case AF_INET:
133 {
134 char addr[4] = {10, 0, counter, get_thread_number ()};
135 TEST_VERIFY (e->h_length == sizeof (addr));
136 TEST_VERIFY (memcmp (e->h_addr_list[0], addr, sizeof (addr)) == 0);
137 }
138 break;
139 case AF_INET6:
140 {
141 char addr[16]
142 = {0x20, 0x01, 0xd, 0xb8, 0, 0, 0, 0, 0, 0,
143 0, counter, 0, get_thread_number (), 0, 0};
144 TEST_VERIFY (e->h_length == sizeof (addr));
145 TEST_VERIFY (memcmp (e->h_addr_list[0], addr, sizeof (addr)) == 0);
146 }
147 break;
148 default:
149 FAIL_EXIT1 ("%s: invalid address family %d", caller, family);
150 }
151 check_have_conf ();
152 }
153
154 /* Check a getaddrinfo result. */
155 static void
156 check_addrinfo (const char *caller, const char *qname,
157 int ret, struct addrinfo *ai, int family, int counter)
158 {
159 if (ret != 0)
160 {
161 support_record_failure ();
162 printf ("error: %s: getaddrinfo for %s failed: %s\n",
163 caller, qname, gai_strerror (ret));
164 return;
165 }
166
167 TEST_VERIFY_EXIT (ai != NULL);
168
169 /* Check that available data matches the requirements. */
170 bool have_ipv4 = false;
171 bool have_ipv6 = false;
172 for (struct addrinfo *p = ai; p != NULL; p = p->ai_next)
173 {
174 TEST_VERIFY (p->ai_socktype == SOCK_STREAM);
175 TEST_VERIFY (p->ai_protocol == IPPROTO_TCP);
176 TEST_VERIFY_EXIT (p->ai_addr != NULL);
177 TEST_VERIFY (p->ai_addr->sa_family == p->ai_family);
178
179 switch (p->ai_family)
180 {
181 case AF_INET:
182 {
183 TEST_VERIFY (!have_ipv4);
184 have_ipv4 = true;
185 struct sockaddr_in *sa = (struct sockaddr_in *) p->ai_addr;
186 TEST_VERIFY (p->ai_addrlen == sizeof (*sa));
187 char addr[4] = {10, 0, counter, get_thread_number ()};
188 TEST_VERIFY (memcmp (&sa->sin_addr, addr, sizeof (addr)) == 0);
189 TEST_VERIFY (ntohs (sa->sin_port) == 80);
190 }
191 break;
192 case AF_INET6:
193 {
194 TEST_VERIFY (!have_ipv6);
195 have_ipv6 = true;
196 struct sockaddr_in6 *sa = (struct sockaddr_in6 *) p->ai_addr;
197 TEST_VERIFY (p->ai_addrlen == sizeof (*sa));
198 char addr[16]
199 = {0x20, 0x01, 0xd, 0xb8, 0, 0, 0, 0, 0, 0,
200 0, counter, 0, get_thread_number (), 0, 0};
201 TEST_VERIFY (memcmp (&sa->sin6_addr, addr, sizeof (addr)) == 0);
202 TEST_VERIFY (ntohs (sa->sin6_port) == 80);
203 }
204 break;
205 default:
206 FAIL_EXIT1 ("%s: invalid address family %d", caller, family);
207 }
208 }
209
210 switch (family)
211 {
212 case AF_INET:
213 TEST_VERIFY (have_ipv4);
214 TEST_VERIFY (!have_ipv6);
215 break;
216 case AF_INET6:
217 TEST_VERIFY (!have_ipv4);
218 TEST_VERIFY (have_ipv6);
219 break;
220 case AF_UNSPEC:
221 TEST_VERIFY (have_ipv4);
222 TEST_VERIFY (have_ipv6);
223 break;
224 default:
225 FAIL_EXIT1 ("%s: invalid address family %d", caller, family);
226 }
227
228 check_have_conf ();
229 }
230
231 /* This barrier ensures that all test threads begin their work
232 simultaneously. */
233 static pthread_barrier_t barrier;
234
235 /* Test gethostbyname2_r (if do_2 is false) or gethostbyname2_r with
236 AF_INET (if do_2 is true). */
237 static void *
238 byname (bool do_2)
239 {
240 int this_thread = get_thread_number ();
241 xpthread_barrier_wait (&barrier);
242 for (int i = 0; i < queries_per_thread; ++i)
243 {
244 char qname[100];
245 snprintf (qname, sizeof (qname), "counter%d.thread%d.example.com",
246 i, this_thread);
247 struct hostent storage;
248 char buf[1000];
249 struct hostent *e = NULL;
250 int herrno;
251 int ret;
252 if (do_2)
253 ret = gethostbyname_r (qname, &storage, buf, sizeof (buf),
254 &e, &herrno);
255 else
256 ret = gethostbyname2_r (qname, AF_INET, &storage, buf, sizeof (buf),
257 &e, &herrno);
258 check_hostent (__func__, do_2 ? "gethostbyname2_r" : "gethostbyname_r",
259 qname, ret, e, AF_INET, i);
260 }
261 check_have_conf ();
262 return NULL;
263 }
264
265 /* Test gethostbyname_r. */
266 static void *
267 thread_byname (void *closure)
268 {
269 return byname (false);
270 }
271
272 /* Test gethostbyname2_r with AF_INET. */
273 static void *
274 thread_byname2 (void *closure)
275 {
276 return byname (true);
277 }
278
279 /* Test gethostbyname2_r with AF_INET6. */
280 static void *
281 thread_byname2_af_inet6 (void *closure)
282 {
283 int this_thread = get_thread_number ();
284 xpthread_barrier_wait (&barrier);
285 for (int i = 0; i < queries_per_thread; ++i)
286 {
287 char qname[100];
288 snprintf (qname, sizeof (qname), "counter%d.thread%d.example.com",
289 i, this_thread);
290 struct hostent storage;
291 char buf[1000];
292 struct hostent *e = NULL;
293 int herrno;
294 int ret = gethostbyname2_r (qname, AF_INET6, &storage, buf, sizeof (buf),
295 &e, &herrno);
296 check_hostent (__func__, "gethostbyname2_r", qname, ret, e, AF_INET6, i);
297 }
298 return NULL;
299 }
300
301 /* Run getaddrinfo tests for FAMILY. */
302 static void *
303 gai (int family)
304 {
305 int this_thread = get_thread_number ();
306 xpthread_barrier_wait (&barrier);
307 for (int i = 0; i < queries_per_thread; ++i)
308 {
309 char qname[100];
310 snprintf (qname, sizeof (qname), "counter%d.thread%d.example.com",
311 i, this_thread);
312 struct addrinfo hints =
313 {
314 .ai_family = family,
315 .ai_socktype = SOCK_STREAM,
316 .ai_protocol = IPPROTO_TCP,
317 };
318 struct addrinfo *ai;
319 int ret = getaddrinfo (qname, "80", &hints, &ai);
320 check_addrinfo (__func__, qname, ret, ai, family, i);
321 if (ret == 0)
322 freeaddrinfo (ai);
323 }
324 return NULL;
325 }
326
327 /* Test getaddrinfo with AF_INET. */
328 static void *
329 thread_gai_inet (void *closure)
330 {
331 return gai (AF_INET);
332 }
333
334 /* Test getaddrinfo with AF_INET6. */
335 static void *
336 thread_gai_inet6 (void *closure)
337 {
338 return gai (AF_INET6);
339 }
340
341 /* Test getaddrinfo with AF_UNSPEC. */
342 static void *
343 thread_gai_unspec (void *closure)
344 {
345 return gai (AF_UNSPEC);
346 }
347
348 /* Description of the chroot environment used to run the tests. */
349 static struct support_chroot *chroot_env;
350
351 /* Set up the chroot environment. */
352 static void
353 prepare (int argc, char **argv)
354 {
355 chroot_env = support_chroot_create
356 ((struct support_chroot_configuration)
357 {
358 .resolv_conf =
359 "search example.com\n"
360 "nameserver 127.0.0.1\n"
361 "nameserver 127.0.0.2\n"
362 "nameserver 127.0.0.3\n",
363 });
364 }
365
366 static int
367 do_test (void)
368 {
369 support_become_root ();
370 if (!support_enter_network_namespace ())
371 return EXIT_UNSUPPORTED;
372 if (!support_can_chroot ())
373 return EXIT_UNSUPPORTED;
374
375 /* Load the shared object outside of the chroot. */
376 TEST_VERIFY (dlopen (LIBNSS_DNS_SO, RTLD_LAZY) != NULL);
377
378 xchroot (chroot_env->path_chroot);
379 TEST_VERIFY_EXIT (chdir ("/") == 0);
380
381 struct sockaddr_in server_address =
382 {
383 .sin_family = AF_INET,
384 .sin_addr = { .s_addr = htonl (INADDR_LOOPBACK) },
385 .sin_port = htons (53)
386 };
387 const struct sockaddr *server_addresses[1] =
388 { (const struct sockaddr *) &server_address };
389
390 struct resolv_test *aux = resolv_test_start
391 ((struct resolv_redirect_config)
392 {
393 .response_callback = response,
394 .nscount = 1,
395 .disable_redirect = true,
396 .server_address_overrides = server_addresses,
397 });
398
399 enum { thread_count = 6 };
400 xpthread_barrier_init (&barrier, NULL, thread_count + 1);
401 pthread_t threads[thread_count];
402 typedef void *(*thread_func) (void *);
403 thread_func thread_funcs[thread_count] =
404 {
405 thread_byname,
406 thread_byname2,
407 thread_byname2_af_inet6,
408 thread_gai_inet,
409 thread_gai_inet6,
410 thread_gai_unspec,
411 };
412 for (int i = 0; i < thread_count; ++i)
413 threads[i] = xpthread_create (NULL, thread_funcs[i], NULL);
414 xpthread_barrier_wait (&barrier); /* Start the test threads. */
415 for (int i = 0; i < thread_count; ++i)
416 xpthread_join (threads[i]);
417
418 resolv_test_end (aux);
419 support_chroot_free (chroot_env);
420
421 return 0;
422 }
423
424 #define PREPARE prepare
425 #include <support/test-driver.c>