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10#define _GNU_SOURCE
11
12#include <arpa/inet.h>
13#include <error.h>
14#include <errno.h>
15#include <linux/net_tstamp.h>
16#include <stdbool.h>
17#include <stdlib.h>
18#include <stdio.h>
19#include <string.h>
20#include <sys/socket.h>
21#include <sys/stat.h>
22#include <sys/time.h>
23#include <sys/types.h>
24#include <time.h>
25#include <unistd.h>
26
27static int cfg_clockid = CLOCK_TAI;
28static bool cfg_do_ipv4;
29static bool cfg_do_ipv6;
30static uint16_t cfg_port = 8000;
31static int cfg_variance_us = 2000;
32
33static uint64_t glob_tstart;
34
35
36struct timed_send {
37 char data;
38 int64_t delay_us;
39};
40
41#define MAX_NUM_PKT 8
42static struct timed_send cfg_in[MAX_NUM_PKT];
43static struct timed_send cfg_out[MAX_NUM_PKT];
44static int cfg_num_pkt;
45
46static uint64_t gettime_ns(void)
47{
48 struct timespec ts;
49
50 if (clock_gettime(cfg_clockid, &ts))
51 error(1, errno, "gettime");
52
53 return ts.tv_sec * (1000ULL * 1000 * 1000) + ts.tv_nsec;
54}
55
56static void do_send_one(int fdt, struct timed_send *ts)
57{
58 char control[CMSG_SPACE(sizeof(uint64_t))];
59 struct msghdr msg = {0};
60 struct iovec iov = {0};
61 struct cmsghdr *cm;
62 uint64_t tdeliver;
63 int ret;
64
65 iov.iov_base = &ts->data;
66 iov.iov_len = 1;
67
68 msg.msg_iov = &iov;
69 msg.msg_iovlen = 1;
70
71 if (ts->delay_us >= 0) {
72 memset(control, 0, sizeof(control));
73 msg.msg_control = &control;
74 msg.msg_controllen = sizeof(control);
75
76 tdeliver = glob_tstart + ts->delay_us * 1000;
77
78 cm = CMSG_FIRSTHDR(&msg);
79 cm->cmsg_level = SOL_SOCKET;
80 cm->cmsg_type = SCM_TXTIME;
81 cm->cmsg_len = CMSG_LEN(sizeof(tdeliver));
82 memcpy(CMSG_DATA(cm), &tdeliver, sizeof(tdeliver));
83 }
84
85 ret = sendmsg(fdt, &msg, 0);
86 if (ret == -1)
87 error(1, errno, "write");
88 if (ret == 0)
89 error(1, 0, "write: 0B");
90
91}
92
93static void do_recv_one(int fdr, struct timed_send *ts)
94{
95 int64_t tstop, texpect;
96 char rbuf[2];
97 int ret;
98
99 ret = recv(fdr, rbuf, sizeof(rbuf), 0);
100 if (ret == -1)
101 error(1, errno, "read");
102 if (ret != 1)
103 error(1, 0, "read: %dB", ret);
104
105 tstop = (gettime_ns() - glob_tstart) / 1000;
106 texpect = ts->delay_us >= 0 ? ts->delay_us : 0;
107
108 fprintf(stderr, "payload:%c delay:%ld expected:%ld (us)\n",
109 rbuf[0], tstop, texpect);
110
111 if (rbuf[0] != ts->data)
112 error(1, 0, "payload mismatch. expected %c", ts->data);
113
114 if (labs(tstop - texpect) > cfg_variance_us)
115 error(1, 0, "exceeds variance (%d us)", cfg_variance_us);
116}
117
118static void do_recv_verify_empty(int fdr)
119{
120 char rbuf[1];
121 int ret;
122
123 ret = recv(fdr, rbuf, sizeof(rbuf), 0);
124 if (ret != -1 || errno != EAGAIN)
125 error(1, 0, "recv: not empty as expected (%d, %d)", ret, errno);
126}
127
128static void setsockopt_txtime(int fd)
129{
130 struct sock_txtime so_txtime_val = { .clockid = cfg_clockid };
131 struct sock_txtime so_txtime_val_read = { 0 };
132 socklen_t vallen = sizeof(so_txtime_val);
133
134 if (setsockopt(fd, SOL_SOCKET, SO_TXTIME,
135 &so_txtime_val, sizeof(so_txtime_val)))
136 error(1, errno, "setsockopt txtime");
137
138 if (getsockopt(fd, SOL_SOCKET, SO_TXTIME,
139 &so_txtime_val_read, &vallen))
140 error(1, errno, "getsockopt txtime");
141
142 if (vallen != sizeof(so_txtime_val) ||
143 memcmp(&so_txtime_val, &so_txtime_val_read, vallen))
144 error(1, 0, "getsockopt txtime: mismatch");
145}
146
147static int setup_tx(struct sockaddr *addr, socklen_t alen)
148{
149 int fd;
150
151 fd = socket(addr->sa_family, SOCK_DGRAM, 0);
152 if (fd == -1)
153 error(1, errno, "socket t");
154
155 if (connect(fd, addr, alen))
156 error(1, errno, "connect");
157
158 setsockopt_txtime(fd);
159
160 return fd;
161}
162
163static int setup_rx(struct sockaddr *addr, socklen_t alen)
164{
165 struct timeval tv = { .tv_usec = 100 * 1000 };
166 int fd;
167
168 fd = socket(addr->sa_family, SOCK_DGRAM, 0);
169 if (fd == -1)
170 error(1, errno, "socket r");
171
172 if (bind(fd, addr, alen))
173 error(1, errno, "bind");
174
175 if (setsockopt(fd, SOL_SOCKET, SO_RCVTIMEO, &tv, sizeof(tv)))
176 error(1, errno, "setsockopt rcv timeout");
177
178 return fd;
179}
180
181static void do_test(struct sockaddr *addr, socklen_t alen)
182{
183 int fdt, fdr, i;
184
185 fprintf(stderr, "\nSO_TXTIME ipv%c clock %s\n",
186 addr->sa_family == PF_INET ? '4' : '6',
187 cfg_clockid == CLOCK_TAI ? "tai" : "monotonic");
188
189 fdt = setup_tx(addr, alen);
190 fdr = setup_rx(addr, alen);
191
192 glob_tstart = gettime_ns();
193
194 for (i = 0; i < cfg_num_pkt; i++)
195 do_send_one(fdt, &cfg_in[i]);
196 for (i = 0; i < cfg_num_pkt; i++)
197 do_recv_one(fdr, &cfg_out[i]);
198
199 do_recv_verify_empty(fdr);
200
201 if (close(fdr))
202 error(1, errno, "close r");
203 if (close(fdt))
204 error(1, errno, "close t");
205}
206
207static int parse_io(const char *optarg, struct timed_send *array)
208{
209 char *arg, *tok;
210 int aoff = 0;
211
212 arg = strdup(optarg);
213 if (!arg)
214 error(1, errno, "strdup");
215
216 while ((tok = strtok(arg, ","))) {
217 arg = NULL;
218
219 if (aoff / 2 == MAX_NUM_PKT)
220 error(1, 0, "exceeds max pkt count (%d)", MAX_NUM_PKT);
221
222 if (aoff & 1) {
223 array->delay_us = strtol(tok, NULL, 0) * 1000;
224 array++;
225 } else {
226 array->data = tok[0];
227 }
228
229 aoff++;
230 }
231
232 free(arg);
233
234 return aoff / 2;
235}
236
237static void parse_opts(int argc, char **argv)
238{
239 int c, ilen, olen;
240
241 while ((c = getopt(argc, argv, "46c:")) != -1) {
242 switch (c) {
243 case '4':
244 cfg_do_ipv4 = true;
245 break;
246 case '6':
247 cfg_do_ipv6 = true;
248 break;
249 case 'c':
250 if (!strcmp(optarg, "tai"))
251 cfg_clockid = CLOCK_TAI;
252 else if (!strcmp(optarg, "monotonic") ||
253 !strcmp(optarg, "mono"))
254 cfg_clockid = CLOCK_MONOTONIC;
255 else
256 error(1, 0, "unknown clock id %s", optarg);
257 break;
258 default:
259 error(1, 0, "parse error at %d", optind);
260 }
261 }
262
263 if (argc - optind != 2)
264 error(1, 0, "Usage: %s [-46] -c <clock> <in> <out>", argv[0]);
265
266 ilen = parse_io(argv[optind], cfg_in);
267 olen = parse_io(argv[optind + 1], cfg_out);
268 if (ilen != olen)
269 error(1, 0, "i/o streams len mismatch (%d, %d)\n", ilen, olen);
270 cfg_num_pkt = ilen;
271}
272
273int main(int argc, char **argv)
274{
275 parse_opts(argc, argv);
276
277 if (cfg_do_ipv6) {
278 struct sockaddr_in6 addr6 = {0};
279
280 addr6.sin6_family = AF_INET6;
281 addr6.sin6_port = htons(cfg_port);
282 addr6.sin6_addr = in6addr_loopback;
283 do_test((void *)&addr6, sizeof(addr6));
284 }
285
286 if (cfg_do_ipv4) {
287 struct sockaddr_in addr4 = {0};
288
289 addr4.sin_family = AF_INET;
290 addr4.sin_port = htons(cfg_port);
291 addr4.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
292 do_test((void *)&addr4, sizeof(addr4));
293 }
294
295 return 0;
296}
297
