xref: /openbmc/linux/tools/testing/selftests/bpf/network_helpers.c (revision 24f68eb5bf14a74027946970a18bc902e19d986a)
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  
37  struct 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  
46  struct 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  
settimeo(int fd,int timeout_ms)54  int 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  
__start_server(int type,int protocol,const struct sockaddr * addr,socklen_t addrlen,int timeout_ms,bool reuseport)80  static 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  		goto error_close;
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  
115  error_close:
116  	save_errno_close(fd);
117  	return -1;
118  }
119  
start_server_proto(int family,int type,int protocol,const char * addr_str,__u16 port,int timeout_ms)120  static 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  
start_server(int family,int type,const char * addr_str,__u16 port,int timeout_ms)133  int 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  
start_mptcp_server(int family,const char * addr_str,__u16 port,int timeout_ms)139  int 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  
start_reuseport_server(int family,int type,const char * addr_str,__u16 port,int timeout_ms,unsigned int nr_listens)146  int *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  
182  close_fds:
183  	free_fds(fds, nr_fds);
184  	return NULL;
185  }
186  
free_fds(int * fds,unsigned int nr_close_fds)187  void 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  
fastopen_connect(int server_fd,const char * data,unsigned int data_len,int timeout_ms)196  int 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  
228  error_close:
229  	save_errno_close(fd);
230  	return -1;
231  }
232  
connect_fd_to_addr(int fd,const struct sockaddr_storage * addr,socklen_t addrlen,const bool must_fail)233  static 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  
260  static const struct network_helper_opts default_opts;
261  
connect_to_fd_opts(int server_fd,const struct network_helper_opts * opts)262  int 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  
274  	if (opts->type) {
275  		type = opts->type;
276  	} else {
277  		if (getsockopt(server_fd, SOL_SOCKET, SO_TYPE, &type, &optlen)) {
278  			log_err("getsockopt(SOL_TYPE)");
279  			return -1;
280  		}
281  	}
282  
283  	if (opts->proto) {
284  		protocol = opts->proto;
285  	} else {
286  		if (getsockopt(server_fd, SOL_SOCKET, SO_PROTOCOL, &protocol, &optlen)) {
287  			log_err("getsockopt(SOL_PROTOCOL)");
288  			return -1;
289  		}
290  	}
291  
292  	addrlen = sizeof(addr);
293  	if (getsockname(server_fd, (struct sockaddr *)&addr, &addrlen)) {
294  		log_err("Failed to get server addr");
295  		return -1;
296  	}
297  
298  	addr_in = (struct sockaddr_in *)&addr;
299  	fd = socket(addr_in->sin_family, type, protocol);
300  	if (fd < 0) {
301  		log_err("Failed to create client socket");
302  		return -1;
303  	}
304  
305  	if (settimeo(fd, opts->timeout_ms))
306  		goto error_close;
307  
308  	if (opts->cc && opts->cc[0] &&
309  	    setsockopt(fd, SOL_TCP, TCP_CONGESTION, opts->cc,
310  		       strlen(opts->cc) + 1))
311  		goto error_close;
312  
313  	if (!opts->noconnect)
314  		if (connect_fd_to_addr(fd, &addr, addrlen, opts->must_fail))
315  			goto error_close;
316  
317  	return fd;
318  
319  error_close:
320  	save_errno_close(fd);
321  	return -1;
322  }
323  
connect_to_fd(int server_fd,int timeout_ms)324  int connect_to_fd(int server_fd, int timeout_ms)
325  {
326  	struct network_helper_opts opts = {
327  		.timeout_ms = timeout_ms,
328  	};
329  
330  	return connect_to_fd_opts(server_fd, &opts);
331  }
332  
connect_fd_to_fd(int client_fd,int server_fd,int timeout_ms)333  int connect_fd_to_fd(int client_fd, int server_fd, int timeout_ms)
334  {
335  	struct sockaddr_storage addr;
336  	socklen_t len = sizeof(addr);
337  
338  	if (settimeo(client_fd, timeout_ms))
339  		return -1;
340  
341  	if (getsockname(server_fd, (struct sockaddr *)&addr, &len)) {
342  		log_err("Failed to get server addr");
343  		return -1;
344  	}
345  
346  	if (connect_fd_to_addr(client_fd, &addr, len, false))
347  		return -1;
348  
349  	return 0;
350  }
351  
make_sockaddr(int family,const char * addr_str,__u16 port,struct sockaddr_storage * addr,socklen_t * len)352  int make_sockaddr(int family, const char *addr_str, __u16 port,
353  		  struct sockaddr_storage *addr, socklen_t *len)
354  {
355  	if (family == AF_INET) {
356  		struct sockaddr_in *sin = (void *)addr;
357  
358  		memset(addr, 0, sizeof(*sin));
359  		sin->sin_family = AF_INET;
360  		sin->sin_port = htons(port);
361  		if (addr_str &&
362  		    inet_pton(AF_INET, addr_str, &sin->sin_addr) != 1) {
363  			log_err("inet_pton(AF_INET, %s)", addr_str);
364  			return -1;
365  		}
366  		if (len)
367  			*len = sizeof(*sin);
368  		return 0;
369  	} else if (family == AF_INET6) {
370  		struct sockaddr_in6 *sin6 = (void *)addr;
371  
372  		memset(addr, 0, sizeof(*sin6));
373  		sin6->sin6_family = AF_INET6;
374  		sin6->sin6_port = htons(port);
375  		if (addr_str &&
376  		    inet_pton(AF_INET6, addr_str, &sin6->sin6_addr) != 1) {
377  			log_err("inet_pton(AF_INET6, %s)", addr_str);
378  			return -1;
379  		}
380  		if (len)
381  			*len = sizeof(*sin6);
382  		return 0;
383  	}
384  	return -1;
385  }
386  
ping_command(int family)387  char *ping_command(int family)
388  {
389  	if (family == AF_INET6) {
390  		/* On some systems 'ping' doesn't support IPv6, so use ping6 if it is present. */
391  		if (!system("which ping6 >/dev/null 2>&1"))
392  			return "ping6";
393  		else
394  			return "ping -6";
395  	}
396  	return "ping";
397  }
398  
399  struct nstoken {
400  	int orig_netns_fd;
401  };
402  
open_netns(const char * name)403  struct nstoken *open_netns(const char *name)
404  {
405  	int nsfd;
406  	char nspath[PATH_MAX];
407  	int err;
408  	struct nstoken *token;
409  
410  	token = calloc(1, sizeof(struct nstoken));
411  	if (!ASSERT_OK_PTR(token, "malloc token"))
412  		return NULL;
413  
414  	token->orig_netns_fd = open("/proc/self/ns/net", O_RDONLY);
415  	if (!ASSERT_GE(token->orig_netns_fd, 0, "open /proc/self/ns/net"))
416  		goto fail;
417  
418  	snprintf(nspath, sizeof(nspath), "%s/%s", "/var/run/netns", name);
419  	nsfd = open(nspath, O_RDONLY | O_CLOEXEC);
420  	if (!ASSERT_GE(nsfd, 0, "open netns fd"))
421  		goto fail;
422  
423  	err = setns(nsfd, CLONE_NEWNET);
424  	close(nsfd);
425  	if (!ASSERT_OK(err, "setns"))
426  		goto fail;
427  
428  	return token;
429  fail:
430  	if (token->orig_netns_fd != -1)
431  		close(token->orig_netns_fd);
432  	free(token);
433  	return NULL;
434  }
435  
close_netns(struct nstoken * token)436  void close_netns(struct nstoken *token)
437  {
438  	if (!token)
439  		return;
440  
441  	ASSERT_OK(setns(token->orig_netns_fd, CLONE_NEWNET), "setns");
442  	close(token->orig_netns_fd);
443  	free(token);
444  }
445  
get_socket_local_port(int sock_fd)446  int get_socket_local_port(int sock_fd)
447  {
448  	struct sockaddr_storage addr;
449  	socklen_t addrlen = sizeof(addr);
450  	int err;
451  
452  	err = getsockname(sock_fd, (struct sockaddr *)&addr, &addrlen);
453  	if (err < 0)
454  		return err;
455  
456  	if (addr.ss_family == AF_INET) {
457  		struct sockaddr_in *sin = (struct sockaddr_in *)&addr;
458  
459  		return sin->sin_port;
460  	} else if (addr.ss_family == AF_INET6) {
461  		struct sockaddr_in6 *sin = (struct sockaddr_in6 *)&addr;
462  
463  		return sin->sin6_port;
464  	}
465  
466  	return -1;
467  }
468