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#include <sys/un.h>
15
16#include <linux/err.h>
17#include <linux/in.h>
18#include <linux/in6.h>
19#include <linux/limits.h>
20
21#include "bpf_util.h"
22#include "network_helpers.h"
23#include "test_progs.h"
24
25#ifndef IPPROTO_MPTCP
26#define IPPROTO_MPTCP 262
27#endif
28
29#define clean_errno() (errno == 0 ? "None" : strerror(errno))
30#define log_err(MSG, ...) ({						\
31			int __save = errno;				\
32			fprintf(stderr, "(%s:%d: errno: %s) " MSG "\n", \
33				__FILE__, __LINE__, clean_errno(),	\
34				##__VA_ARGS__);				\
35			errno = __save;					\
36})
37
38struct ipv4_packet pkt_v4 = {
39	.eth.h_proto = __bpf_constant_htons(ETH_P_IP),
40	.iph.ihl = 5,
41	.iph.protocol = IPPROTO_TCP,
42	.iph.tot_len = __bpf_constant_htons(MAGIC_BYTES),
43	.tcp.urg_ptr = 123,
44	.tcp.doff = 5,
45};
46
47struct ipv6_packet pkt_v6 = {
48	.eth.h_proto = __bpf_constant_htons(ETH_P_IPV6),
49	.iph.nexthdr = IPPROTO_TCP,
50	.iph.payload_len = __bpf_constant_htons(MAGIC_BYTES),
51	.tcp.urg_ptr = 123,
52	.tcp.doff = 5,
53};
54
55int settimeo(int fd, int timeout_ms)
56{
57	struct timeval timeout = { .tv_sec = 3 };
58
59	if (timeout_ms > 0) {
60		timeout.tv_sec = timeout_ms / 1000;
61		timeout.tv_usec = (timeout_ms % 1000) * 1000;
62	}
63
64	if (setsockopt(fd, SOL_SOCKET, SO_RCVTIMEO, &timeout,
65		       sizeof(timeout))) {
66		log_err("Failed to set SO_RCVTIMEO");
67		return -1;
68	}
69
70	if (setsockopt(fd, SOL_SOCKET, SO_SNDTIMEO, &timeout,
71		       sizeof(timeout))) {
72		log_err("Failed to set SO_SNDTIMEO");
73		return -1;
74	}
75
76	return 0;
77}
78
79#define save_errno_close(fd) ({ int __save = errno; close(fd); errno = __save; })
80
81static int __start_server(int type, int protocol, const struct sockaddr *addr,
82			  socklen_t addrlen, int timeout_ms, bool reuseport)
83{
84	int on = 1;
85	int fd;
86
87	fd = socket(addr->sa_family, type, protocol);
88	if (fd < 0) {
89		log_err("Failed to create server socket");
90		return -1;
91	}
92
93	if (settimeo(fd, timeout_ms))
94		goto error_close;
95
96	if (reuseport &&
97	    setsockopt(fd, SOL_SOCKET, SO_REUSEPORT, &on, sizeof(on))) {
98		log_err("Failed to set SO_REUSEPORT");
99		goto error_close;
100	}
101
102	if (bind(fd, addr, addrlen) < 0) {
103		log_err("Failed to bind socket");
104		goto error_close;
105	}
106
107	if (type == SOCK_STREAM) {
108		if (listen(fd, 1) < 0) {
109			log_err("Failed to listed on socket");
110			goto error_close;
111		}
112	}
113
114	return fd;
115
116error_close:
117	save_errno_close(fd);
118	return -1;
119}
120
121static int start_server_proto(int family, int type, int protocol,
122			      const char *addr_str, __u16 port, int timeout_ms)
123{
124	struct sockaddr_storage addr;
125	socklen_t addrlen;
126
127	if (make_sockaddr(family, addr_str, port, &addr, &addrlen))
128		return -1;
129
130	return __start_server(type, protocol, (struct sockaddr *)&addr,
131			      addrlen, timeout_ms, false);
132}
133
134int start_server(int family, int type, const char *addr_str, __u16 port,
135		 int timeout_ms)
136{
137	return start_server_proto(family, type, 0, addr_str, port, timeout_ms);
138}
139
140int start_mptcp_server(int family, const char *addr_str, __u16 port,
141		       int timeout_ms)
142{
143	return start_server_proto(family, SOCK_STREAM, IPPROTO_MPTCP, addr_str,
144				  port, timeout_ms);
145}
146
147int *start_reuseport_server(int family, int type, const char *addr_str,
148			    __u16 port, int timeout_ms, unsigned int nr_listens)
149{
150	struct sockaddr_storage addr;
151	unsigned int nr_fds = 0;
152	socklen_t addrlen;
153	int *fds;
154
155	if (!nr_listens)
156		return NULL;
157
158	if (make_sockaddr(family, addr_str, port, &addr, &addrlen))
159		return NULL;
160
161	fds = malloc(sizeof(*fds) * nr_listens);
162	if (!fds)
163		return NULL;
164
165	fds[0] = __start_server(type, 0, (struct sockaddr *)&addr, addrlen,
166				timeout_ms, true);
167	if (fds[0] == -1)
168		goto close_fds;
169	nr_fds = 1;
170
171	if (getsockname(fds[0], (struct sockaddr *)&addr, &addrlen))
172		goto close_fds;
173
174	for (; nr_fds < nr_listens; nr_fds++) {
175		fds[nr_fds] = __start_server(type, 0, (struct sockaddr *)&addr,
176					     addrlen, timeout_ms, true);
177		if (fds[nr_fds] == -1)
178			goto close_fds;
179	}
180
181	return fds;
182
183close_fds:
184	free_fds(fds, nr_fds);
185	return NULL;
186}
187
188void free_fds(int *fds, unsigned int nr_close_fds)
189{
190	if (fds) {
191		while (nr_close_fds)
192			close(fds[--nr_close_fds]);
193		free(fds);
194	}
195}
196
197int fastopen_connect(int server_fd, const char *data, unsigned int data_len,
198		     int timeout_ms)
199{
200	struct sockaddr_storage addr;
201	socklen_t addrlen = sizeof(addr);
202	struct sockaddr_in *addr_in;
203	int fd, ret;
204
205	if (getsockname(server_fd, (struct sockaddr *)&addr, &addrlen)) {
206		log_err("Failed to get server addr");
207		return -1;
208	}
209
210	addr_in = (struct sockaddr_in *)&addr;
211	fd = socket(addr_in->sin_family, SOCK_STREAM, 0);
212	if (fd < 0) {
213		log_err("Failed to create client socket");
214		return -1;
215	}
216
217	if (settimeo(fd, timeout_ms))
218		goto error_close;
219
220	ret = sendto(fd, data, data_len, MSG_FASTOPEN, (struct sockaddr *)&addr,
221		     addrlen);
222	if (ret != data_len) {
223		log_err("sendto(data, %u) != %d\n", data_len, ret);
224		goto error_close;
225	}
226
227	return fd;
228
229error_close:
230	save_errno_close(fd);
231	return -1;
232}
233
234static int connect_fd_to_addr(int fd,
235			      const struct sockaddr_storage *addr,
236			      socklen_t addrlen, const bool must_fail)
237{
238	int ret;
239
240	errno = 0;
241	ret = connect(fd, (const struct sockaddr *)addr, addrlen);
242	if (must_fail) {
243		if (!ret) {
244			log_err("Unexpected success to connect to server");
245			return -1;
246		}
247		if (errno != EPERM) {
248			log_err("Unexpected error from connect to server");
249			return -1;
250		}
251	} else {
252		if (ret) {
253			log_err("Failed to connect to server");
254			return -1;
255		}
256	}
257
258	return 0;
259}
260
261int connect_to_addr(const struct sockaddr_storage *addr, socklen_t addrlen, int type)
262{
263	int fd;
264
265	fd = socket(addr->ss_family, type, 0);
266	if (fd < 0) {
267		log_err("Failed to create client socket");
268		return -1;
269	}
270
271	if (connect_fd_to_addr(fd, addr, addrlen, false))
272		goto error_close;
273
274	return fd;
275
276error_close:
277	save_errno_close(fd);
278	return -1;
279}
280
281static const struct network_helper_opts default_opts;
282
283int connect_to_fd_opts(int server_fd, const struct network_helper_opts *opts)
284{
285	struct sockaddr_storage addr;
286	struct sockaddr_in *addr_in;
287	socklen_t addrlen, optlen;
288	int fd, type, protocol;
289
290	if (!opts)
291		opts = &default_opts;
292
293	optlen = sizeof(type);
294
295	if (opts->type) {
296		type = opts->type;
297	} else {
298		if (getsockopt(server_fd, SOL_SOCKET, SO_TYPE, &type, &optlen)) {
299			log_err("getsockopt(SOL_TYPE)");
300			return -1;
301		}
302	}
303
304	if (opts->proto) {
305		protocol = opts->proto;
306	} else {
307		if (getsockopt(server_fd, SOL_SOCKET, SO_PROTOCOL, &protocol, &optlen)) {
308			log_err("getsockopt(SOL_PROTOCOL)");
309			return -1;
310		}
311	}
312
313	addrlen = sizeof(addr);
314	if (getsockname(server_fd, (struct sockaddr *)&addr, &addrlen)) {
315		log_err("Failed to get server addr");
316		return -1;
317	}
318
319	addr_in = (struct sockaddr_in *)&addr;
320	fd = socket(addr_in->sin_family, type, protocol);
321	if (fd < 0) {
322		log_err("Failed to create client socket");
323		return -1;
324	}
325
326	if (settimeo(fd, opts->timeout_ms))
327		goto error_close;
328
329	if (opts->cc && opts->cc[0] &&
330	    setsockopt(fd, SOL_TCP, TCP_CONGESTION, opts->cc,
331		       strlen(opts->cc) + 1))
332		goto error_close;
333
334	if (!opts->noconnect)
335		if (connect_fd_to_addr(fd, &addr, addrlen, opts->must_fail))
336			goto error_close;
337
338	return fd;
339
340error_close:
341	save_errno_close(fd);
342	return -1;
343}
344
345int connect_to_fd(int server_fd, int timeout_ms)
346{
347	struct network_helper_opts opts = {
348		.timeout_ms = timeout_ms,
349	};
350
351	return connect_to_fd_opts(server_fd, &opts);
352}
353
354int connect_fd_to_fd(int client_fd, int server_fd, int timeout_ms)
355{
356	struct sockaddr_storage addr;
357	socklen_t len = sizeof(addr);
358
359	if (settimeo(client_fd, timeout_ms))
360		return -1;
361
362	if (getsockname(server_fd, (struct sockaddr *)&addr, &len)) {
363		log_err("Failed to get server addr");
364		return -1;
365	}
366
367	if (connect_fd_to_addr(client_fd, &addr, len, false))
368		return -1;
369
370	return 0;
371}
372
373int make_sockaddr(int family, const char *addr_str, __u16 port,
374		  struct sockaddr_storage *addr, socklen_t *len)
375{
376	if (family == AF_INET) {
377		struct sockaddr_in *sin = (void *)addr;
378
379		memset(addr, 0, sizeof(*sin));
380		sin->sin_family = AF_INET;
381		sin->sin_port = htons(port);
382		if (addr_str &&
383		    inet_pton(AF_INET, addr_str, &sin->sin_addr) != 1) {
384			log_err("inet_pton(AF_INET, %s)", addr_str);
385			return -1;
386		}
387		if (len)
388			*len = sizeof(*sin);
389		return 0;
390	} else if (family == AF_INET6) {
391		struct sockaddr_in6 *sin6 = (void *)addr;
392
393		memset(addr, 0, sizeof(*sin6));
394		sin6->sin6_family = AF_INET6;
395		sin6->sin6_port = htons(port);
396		if (addr_str &&
397		    inet_pton(AF_INET6, addr_str, &sin6->sin6_addr) != 1) {
398			log_err("inet_pton(AF_INET6, %s)", addr_str);
399			return -1;
400		}
401		if (len)
402			*len = sizeof(*sin6);
403		return 0;
404	} else if (family == AF_UNIX) {
405		/* Note that we always use abstract unix sockets to avoid having
406		 * to clean up leftover files.
407		 */
408		struct sockaddr_un *sun = (void *)addr;
409
410		memset(addr, 0, sizeof(*sun));
411		sun->sun_family = family;
412		sun->sun_path[0] = 0;
413		strcpy(sun->sun_path + 1, addr_str);
414		if (len)
415			*len = offsetof(struct sockaddr_un, sun_path) + 1 + strlen(addr_str);
416		return 0;
417	}
418	return -1;
419}
420
421char *ping_command(int family)
422{
423	if (family == AF_INET6) {
424		/* On some systems 'ping' doesn't support IPv6, so use ping6 if it is present. */
425		if (!system("which ping6 >/dev/null 2>&1"))
426			return "ping6";
427		else
428			return "ping -6";
429	}
430	return "ping";
431}
432
433struct nstoken {
434	int orig_netns_fd;
435};
436
437struct nstoken *open_netns(const char *name)
438{
439	int nsfd;
440	char nspath[PATH_MAX];
441	int err;
442	struct nstoken *token;
443
444	token = calloc(1, sizeof(struct nstoken));
445	if (!ASSERT_OK_PTR(token, "malloc token"))
446		return NULL;
447
448	token->orig_netns_fd = open("/proc/self/ns/net", O_RDONLY);
449	if (!ASSERT_GE(token->orig_netns_fd, 0, "open /proc/self/ns/net"))
450		goto fail;
451
452	snprintf(nspath, sizeof(nspath), "%s/%s", "/var/run/netns", name);
453	nsfd = open(nspath, O_RDONLY | O_CLOEXEC);
454	if (!ASSERT_GE(nsfd, 0, "open netns fd"))
455		goto fail;
456
457	err = setns(nsfd, CLONE_NEWNET);
458	close(nsfd);
459	if (!ASSERT_OK(err, "setns"))
460		goto fail;
461
462	return token;
463fail:
464	free(token);
465	return NULL;
466}
467
468void close_netns(struct nstoken *token)
469{
470	if (!token)
471		return;
472
473	ASSERT_OK(setns(token->orig_netns_fd, CLONE_NEWNET), "setns");
474	close(token->orig_netns_fd);
475	free(token);
476}
477
478int get_socket_local_port(int sock_fd)
479{
480	struct sockaddr_storage addr;
481	socklen_t addrlen = sizeof(addr);
482	int err;
483
484	err = getsockname(sock_fd, (struct sockaddr *)&addr, &addrlen);
485	if (err < 0)
486		return err;
487
488	if (addr.ss_family == AF_INET) {
489		struct sockaddr_in *sin = (struct sockaddr_in *)&addr;
490
491		return sin->sin_port;
492	} else if (addr.ss_family == AF_INET6) {
493		struct sockaddr_in6 *sin = (struct sockaddr_in6 *)&addr;
494
495		return sin->sin6_port;
496	}
497
498	return -1;
499}
500