1// SPDX-License-Identifier: GPL-2.0-only
  2#define _GNU_SOURCE
  3
  4#include <errno.h>
  5#include <stdbool.h>
  6#include <stdio.h>
  7#include <string.h>
  8#include <unistd.h>
  9#include <sched.h>
 10
 11#include <arpa/inet.h>
 12#include <sys/mount.h>
 13#include <sys/stat.h>
 14
 15#include <linux/err.h>
 16#include <linux/in.h>
 17#include <linux/in6.h>
 18#include <linux/limits.h>
 19
 20#include "bpf_util.h"
 21#include "network_helpers.h"
 22#include "test_progs.h"
 23
 24#ifndef IPPROTO_MPTCP
 25#define IPPROTO_MPTCP 262
 26#endif
 27
 28#define clean_errno() (errno == 0 ? "None" : strerror(errno))
 29#define log_err(MSG, ...) ({						\
 30			int __save = errno;				\
 31			fprintf(stderr, "(%s:%d: errno: %s) " MSG "\n", \
 32				__FILE__, __LINE__, clean_errno(),	\
 33				##__VA_ARGS__);				\
 34			errno = __save;					\
 35})
 36
 37struct ipv4_packet pkt_v4 = {
 38	.eth.h_proto = __bpf_constant_htons(ETH_P_IP),
 39	.iph.ihl = 5,
 40	.iph.protocol = IPPROTO_TCP,
 41	.iph.tot_len = __bpf_constant_htons(MAGIC_BYTES),
 42	.tcp.urg_ptr = 123,
 43	.tcp.doff = 5,
 44};
 45
 46struct ipv6_packet pkt_v6 = {
 47	.eth.h_proto = __bpf_constant_htons(ETH_P_IPV6),
 48	.iph.nexthdr = IPPROTO_TCP,
 49	.iph.payload_len = __bpf_constant_htons(MAGIC_BYTES),
 50	.tcp.urg_ptr = 123,
 51	.tcp.doff = 5,
 52};
 53
 54int settimeo(int fd, int timeout_ms)
 55{
 56	struct timeval timeout = { .tv_sec = 3 };
 57
 58	if (timeout_ms > 0) {
 59		timeout.tv_sec = timeout_ms / 1000;
 60		timeout.tv_usec = (timeout_ms % 1000) * 1000;
 61	}
 62
 63	if (setsockopt(fd, SOL_SOCKET, SO_RCVTIMEO, &timeout,
 64		       sizeof(timeout))) {
 65		log_err("Failed to set SO_RCVTIMEO");
 66		return -1;
 67	}
 68
 69	if (setsockopt(fd, SOL_SOCKET, SO_SNDTIMEO, &timeout,
 70		       sizeof(timeout))) {
 71		log_err("Failed to set SO_SNDTIMEO");
 72		return -1;
 73	}
 74
 75	return 0;
 76}
 77
 78#define save_errno_close(fd) ({ int __save = errno; close(fd); errno = __save; })
 79
 80static int __start_server(int type, int protocol, const struct sockaddr *addr,
 81			  socklen_t addrlen, int timeout_ms, bool reuseport)
 82{
 83	int on = 1;
 84	int fd;
 85
 86	fd = socket(addr->sa_family, type, protocol);
 87	if (fd < 0) {
 88		log_err("Failed to create server socket");
 89		return -1;
 90	}
 91
 92	if (settimeo(fd, timeout_ms))
 93		goto error_close;
 94
 95	if (reuseport &&
 96	    setsockopt(fd, SOL_SOCKET, SO_REUSEPORT, &on, sizeof(on))) {
 97		log_err("Failed to set SO_REUSEPORT");
 98		return -1;
 99	}
100
101	if (bind(fd, addr, addrlen) < 0) {
102		log_err("Failed to bind socket");
103		goto error_close;
104	}
105
106	if (type == SOCK_STREAM) {
107		if (listen(fd, 1) < 0) {
108			log_err("Failed to listed on socket");
109			goto error_close;
110		}
111	}
112
113	return fd;
114
115error_close:
116	save_errno_close(fd);
117	return -1;
118}
119
120static int start_server_proto(int family, int type, int protocol,
121			      const char *addr_str, __u16 port, int timeout_ms)
122{
123	struct sockaddr_storage addr;
124	socklen_t addrlen;
125
126	if (make_sockaddr(family, addr_str, port, &addr, &addrlen))
127		return -1;
128
129	return __start_server(type, protocol, (struct sockaddr *)&addr,
130			      addrlen, timeout_ms, false);
131}
132
133int start_server(int family, int type, const char *addr_str, __u16 port,
134		 int timeout_ms)
135{
136	return start_server_proto(family, type, 0, addr_str, port, timeout_ms);
137}
138
139int start_mptcp_server(int family, const char *addr_str, __u16 port,
140		       int timeout_ms)
141{
142	return start_server_proto(family, SOCK_STREAM, IPPROTO_MPTCP, addr_str,
143				  port, timeout_ms);
144}
145
146int *start_reuseport_server(int family, int type, const char *addr_str,
147			    __u16 port, int timeout_ms, unsigned int nr_listens)
148{
149	struct sockaddr_storage addr;
150	unsigned int nr_fds = 0;
151	socklen_t addrlen;
152	int *fds;
153
154	if (!nr_listens)
155		return NULL;
156
157	if (make_sockaddr(family, addr_str, port, &addr, &addrlen))
158		return NULL;
159
160	fds = malloc(sizeof(*fds) * nr_listens);
161	if (!fds)
162		return NULL;
163
164	fds[0] = __start_server(type, 0, (struct sockaddr *)&addr, addrlen,
165				timeout_ms, true);
166	if (fds[0] == -1)
167		goto close_fds;
168	nr_fds = 1;
169
170	if (getsockname(fds[0], (struct sockaddr *)&addr, &addrlen))
171		goto close_fds;
172
173	for (; nr_fds < nr_listens; nr_fds++) {
174		fds[nr_fds] = __start_server(type, 0, (struct sockaddr *)&addr,
175					     addrlen, timeout_ms, true);
176		if (fds[nr_fds] == -1)
177			goto close_fds;
178	}
179
180	return fds;
181
182close_fds:
183	free_fds(fds, nr_fds);
184	return NULL;
185}
186
187void free_fds(int *fds, unsigned int nr_close_fds)
188{
189	if (fds) {
190		while (nr_close_fds)
191			close(fds[--nr_close_fds]);
192		free(fds);
193	}
194}
195
196int fastopen_connect(int server_fd, const char *data, unsigned int data_len,
197		     int timeout_ms)
198{
199	struct sockaddr_storage addr;
200	socklen_t addrlen = sizeof(addr);
201	struct sockaddr_in *addr_in;
202	int fd, ret;
203
204	if (getsockname(server_fd, (struct sockaddr *)&addr, &addrlen)) {
205		log_err("Failed to get server addr");
206		return -1;
207	}
208
209	addr_in = (struct sockaddr_in *)&addr;
210	fd = socket(addr_in->sin_family, SOCK_STREAM, 0);
211	if (fd < 0) {
212		log_err("Failed to create client socket");
213		return -1;
214	}
215
216	if (settimeo(fd, timeout_ms))
217		goto error_close;
218
219	ret = sendto(fd, data, data_len, MSG_FASTOPEN, (struct sockaddr *)&addr,
220		     addrlen);
221	if (ret != data_len) {
222		log_err("sendto(data, %u) != %d\n", data_len, ret);
223		goto error_close;
224	}
225
226	return fd;
227
228error_close:
229	save_errno_close(fd);
230	return -1;
231}
232
233static int connect_fd_to_addr(int fd,
234			      const struct sockaddr_storage *addr,
235			      socklen_t addrlen, const bool must_fail)
236{
237	int ret;
238
239	errno = 0;
240	ret = connect(fd, (const struct sockaddr *)addr, addrlen);
241	if (must_fail) {
242		if (!ret) {
243			log_err("Unexpected success to connect to server");
244			return -1;
245		}
246		if (errno != EPERM) {
247			log_err("Unexpected error from connect to server");
248			return -1;
249		}
250	} else {
251		if (ret) {
252			log_err("Failed to connect to server");
253			return -1;
254		}
255	}
256
257	return 0;
258}
259
260static const struct network_helper_opts default_opts;
261
262int connect_to_fd_opts(int server_fd, const struct network_helper_opts *opts)
263{
264	struct sockaddr_storage addr;
265	struct sockaddr_in *addr_in;
266	socklen_t addrlen, optlen;
267	int fd, type, protocol;
268
269	if (!opts)
270		opts = &default_opts;
271
272	optlen = sizeof(type);
273	if (getsockopt(server_fd, SOL_SOCKET, SO_TYPE, &type, &optlen)) {
274		log_err("getsockopt(SOL_TYPE)");
275		return -1;
276	}
277
278	if (getsockopt(server_fd, SOL_SOCKET, SO_PROTOCOL, &protocol, &optlen)) {
279		log_err("getsockopt(SOL_PROTOCOL)");
280		return -1;
281	}
282
283	addrlen = sizeof(addr);
284	if (getsockname(server_fd, (struct sockaddr *)&addr, &addrlen)) {
285		log_err("Failed to get server addr");
286		return -1;
287	}
288
289	addr_in = (struct sockaddr_in *)&addr;
290	fd = socket(addr_in->sin_family, type, protocol);
291	if (fd < 0) {
292		log_err("Failed to create client socket");
293		return -1;
294	}
295
296	if (settimeo(fd, opts->timeout_ms))
297		goto error_close;
298
299	if (opts->cc && opts->cc[0] &&
300	    setsockopt(fd, SOL_TCP, TCP_CONGESTION, opts->cc,
301		       strlen(opts->cc) + 1))
302		goto error_close;
303
304	if (connect_fd_to_addr(fd, &addr, addrlen, opts->must_fail))
305		goto error_close;
306
307	return fd;
308
309error_close:
310	save_errno_close(fd);
311	return -1;
312}
313
314int connect_to_fd(int server_fd, int timeout_ms)
315{
316	struct network_helper_opts opts = {
317		.timeout_ms = timeout_ms,
318	};
319
320	return connect_to_fd_opts(server_fd, &opts);
321}
322
323int connect_fd_to_fd(int client_fd, int server_fd, int timeout_ms)
324{
325	struct sockaddr_storage addr;
326	socklen_t len = sizeof(addr);
327
328	if (settimeo(client_fd, timeout_ms))
329		return -1;
330
331	if (getsockname(server_fd, (struct sockaddr *)&addr, &len)) {
332		log_err("Failed to get server addr");
333		return -1;
334	}
335
336	if (connect_fd_to_addr(client_fd, &addr, len, false))
337		return -1;
338
339	return 0;
340}
341
342int make_sockaddr(int family, const char *addr_str, __u16 port,
343		  struct sockaddr_storage *addr, socklen_t *len)
344{
345	if (family == AF_INET) {
346		struct sockaddr_in *sin = (void *)addr;
347
348		memset(addr, 0, sizeof(*sin));
349		sin->sin_family = AF_INET;
350		sin->sin_port = htons(port);
351		if (addr_str &&
352		    inet_pton(AF_INET, addr_str, &sin->sin_addr) != 1) {
353			log_err("inet_pton(AF_INET, %s)", addr_str);
354			return -1;
355		}
356		if (len)
357			*len = sizeof(*sin);
358		return 0;
359	} else if (family == AF_INET6) {
360		struct sockaddr_in6 *sin6 = (void *)addr;
361
362		memset(addr, 0, sizeof(*sin6));
363		sin6->sin6_family = AF_INET6;
364		sin6->sin6_port = htons(port);
365		if (addr_str &&
366		    inet_pton(AF_INET6, addr_str, &sin6->sin6_addr) != 1) {
367			log_err("inet_pton(AF_INET6, %s)", addr_str);
368			return -1;
369		}
370		if (len)
371			*len = sizeof(*sin6);
372		return 0;
373	}
374	return -1;
375}
376
377char *ping_command(int family)
378{
379	if (family == AF_INET6) {
380		/* On some systems 'ping' doesn't support IPv6, so use ping6 if it is present. */
381		if (!system("which ping6 >/dev/null 2>&1"))
382			return "ping6";
383		else
384			return "ping -6";
385	}
386	return "ping";
387}
388
389struct nstoken {
390	int orig_netns_fd;
391};
392
393struct nstoken *open_netns(const char *name)
394{
395	int nsfd;
396	char nspath[PATH_MAX];
397	int err;
398	struct nstoken *token;
399
400	token = calloc(1, sizeof(struct nstoken));
401	if (!ASSERT_OK_PTR(token, "malloc token"))
402		return NULL;
403
404	token->orig_netns_fd = open("/proc/self/ns/net", O_RDONLY);
405	if (!ASSERT_GE(token->orig_netns_fd, 0, "open /proc/self/ns/net"))
406		goto fail;
407
408	snprintf(nspath, sizeof(nspath), "%s/%s", "/var/run/netns", name);
409	nsfd = open(nspath, O_RDONLY | O_CLOEXEC);
410	if (!ASSERT_GE(nsfd, 0, "open netns fd"))
411		goto fail;
412
413	err = setns(nsfd, CLONE_NEWNET);
414	close(nsfd);
415	if (!ASSERT_OK(err, "setns"))
416		goto fail;
417
418	return token;
419fail:
420	free(token);
421	return NULL;
422}
423
424void close_netns(struct nstoken *token)
425{
426	ASSERT_OK(setns(token->orig_netns_fd, CLONE_NEWNET), "setns");
427	close(token->orig_netns_fd);
428	free(token);
429}