1 // SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause)
2 // Copyright (c) 2021 Wenbo Zhang
3 //
4 // Based on tcprtt(8) from BCC by zhenwei pi.
5 // 06-Aug-2021 Wenbo Zhang Created this.
6 #define _DEFAULT_SOURCE
7 #include <arpa/inet.h>
8 #include <argp.h>
9 #include <stdio.h>
10 #include <signal.h>
11 #include <unistd.h>
12 #include <time.h>
13 #include <bpf/libbpf.h>
14 #include <bpf/bpf.h>
15 #include "tcprtt.h"
16 #include "tcprtt.skel.h"
17 #include "trace_helpers.h"
18
19 static struct env {
20 __u16 lport;
21 __u16 rport;
22 __u32 laddr;
23 __u32 raddr;
24 __u8 laddr_v6[IPV6_LEN];
25 __u8 raddr_v6[IPV6_LEN];
26 bool milliseconds;
27 time_t duration;
28 time_t interval;
29 bool timestamp;
30 bool laddr_hist;
31 bool raddr_hist;
32 bool extended;
33 bool verbose;
34 } env = {
35 .interval = 99999999,
36 };
37
38 static volatile bool exiting;
39
40 const char *argp_program_version = "tcprtt 0.1";
41 const char *argp_program_bug_address =
42 "https://github.com/iovisor/bcc/tree/master/libbpf-tools";
43 const char argp_program_doc[] =
44 "Summarize TCP RTT as a histogram.\n"
45 "\n"
46 "USAGE: \n"
47 "\n"
48 "EXAMPLES:\n"
49 " tcprtt # summarize TCP RTT\n"
50 " tcprtt -i 1 -d 10 # print 1 second summaries, 10 times\n"
51 " tcprtt -m -T # summarize in millisecond, and timestamps\n"
52 " tcprtt -p # filter for local port\n"
53 " tcprtt -P # filter for remote port\n"
54 " tcprtt -a # filter for local address\n"
55 " tcprtt -A # filter for remote address\n"
56 " tcprtt -b # show sockets histogram by local address\n"
57 " tcprtt -B # show sockets histogram by remote address\n"
58 " tcprtt -e # show extension summary(average)\n";
59
60 static const struct argp_option opts[] = {
61 { "interval", 'i', "INTERVAL", 0, "summary interval, seconds" },
62 { "duration", 'd', "DURATION", 0, "total duration of trace, seconds" },
63 { "timestamp", 'T', NULL, 0, "include timestamp on output" },
64 { "millisecond", 'm', NULL, 0, "millisecond histogram" },
65 { "lport", 'p', "LPORT", 0, "filter for local port" },
66 { "rport", 'P', "RPORT", 0, "filter for remote port" },
67 { "laddr", 'a', "LADDR", 0, "filter for local address" },
68 { "raddr", 'A', "RADDR", 0, "filter for remote address" },
69 { "byladdr", 'b', NULL, 0,
70 "show sockets histogram by local address" },
71 { "byraddr", 'B', NULL, 0,
72 "show sockets histogram by remote address" },
73 { "extension", 'e', NULL, 0, "show extension summary(average)" },
74 { "verbose", 'v', NULL, 0, "Verbose debug output" },
75 { NULL, 'h', NULL, OPTION_HIDDEN, "Show the full help" },
76 {},
77 };
78
parse_arg(int key,char * arg,struct argp_state * state)79 static error_t parse_arg(int key, char *arg, struct argp_state *state)
80 {
81 struct in_addr addr;
82 struct in6_addr addr_v6;
83
84 switch (key) {
85 case 'h':
86 argp_state_help(state, stderr, ARGP_HELP_STD_HELP);
87 break;
88 case 'v':
89 env.verbose = true;
90 break;
91 case 'i':
92 errno = 0;
93 env.interval = strtol(arg, NULL, 10);
94 if (errno || env.interval <= 0) {
95 fprintf(stderr, "invalid interval: %s\n", arg);
96 argp_usage(state);
97 }
98 break;
99 case 'd':
100 errno = 0;
101 env.duration = strtol(arg, NULL, 10);
102 if (errno || env.duration <= 0) {
103 fprintf(stderr, "invalid duration: %s\n", arg);
104 argp_usage(state);
105 }
106 break;
107 case 'T':
108 env.timestamp = true;
109 break;
110 case 'm':
111 env.milliseconds = true;
112 break;
113 case 'p':
114 errno = 0;
115 env.lport = strtoul(arg, NULL, 10);
116 if (errno) {
117 fprintf(stderr, "invalid lport: %s\n", arg);
118 argp_usage(state);
119 }
120 env.lport = htons(env.lport);
121 break;
122 case 'P':
123 errno = 0;
124 env.rport = strtoul(arg, NULL, 10);
125 if (errno) {
126 fprintf(stderr, "invalid rport: %s\n", arg);
127 argp_usage(state);
128 }
129 env.rport = htons(env.rport);
130 break;
131 case 'a':
132 if (strchr(arg, ':')) {
133 if (inet_pton(AF_INET6, arg, &addr_v6) < 1) {
134 fprintf(stderr, "invalid local IPv6 address: %s\n", arg);
135 argp_usage(state);
136 }
137 memcpy(env.laddr_v6, &addr_v6, sizeof(env.laddr_v6));
138 } else {
139 if (inet_pton(AF_INET, arg, &addr) < 0) {
140 fprintf(stderr, "invalid local address: %s\n", arg);
141 argp_usage(state);
142 }
143 env.laddr = addr.s_addr;
144 }
145 break;
146 case 'A':
147 if (strchr(arg, ':')) {
148 if (inet_pton(AF_INET6, arg, &addr_v6) < 1) {
149 fprintf(stderr, "invalid remote address: %s\n", arg);
150 argp_usage(state);
151 }
152 memcpy(env.raddr_v6, &addr_v6, sizeof(env.raddr_v6));
153 } else {
154 if (inet_pton(AF_INET, arg, &addr) < 0) {
155 fprintf(stderr, "invalid remote address: %s\n", arg);
156 argp_usage(state);
157 }
158 env.raddr = addr.s_addr;
159 }
160 break;
161 case 'b':
162 env.laddr_hist = true;
163 break;
164 case 'B':
165 env.raddr_hist = true;
166 break;
167 case 'e':
168 env.extended = true;
169 break;
170 default:
171 return ARGP_ERR_UNKNOWN;
172 }
173 return 0;
174 }
175
libbpf_print_fn(enum libbpf_print_level level,const char * format,va_list args)176 static int libbpf_print_fn(enum libbpf_print_level level, const char *format, va_list args)
177 {
178 if (level == LIBBPF_DEBUG && !env.verbose)
179 return 0;
180 return vfprintf(stderr, format, args);
181 }
182
sig_handler(int sig)183 static void sig_handler(int sig)
184 {
185 exiting = true;
186 }
187
print_map(struct bpf_map * map)188 static int print_map(struct bpf_map *map)
189 {
190 const char *units = env.milliseconds ? "msecs" : "usecs";
191 struct hist_key *lookup_key = NULL, next_key;
192 int err, fd = bpf_map__fd(map);
193 struct hist hist;
194
195 while (!bpf_map_get_next_key(fd, lookup_key, &next_key)) {
196 err = bpf_map_lookup_elem(fd, &next_key, &hist);
197 if (err < 0) {
198 fprintf(stderr, "failed to lookup infos: %d\n", err);
199 return -1;
200 }
201
202
203 if (env.laddr_hist)
204 printf("Local Address = ");
205 else if (env.raddr_hist)
206 printf("Remote Address = ");
207 else
208 printf("All Addresses = ****** ");
209
210 if (env.laddr_hist || env.raddr_hist) {
211 __u16 family = next_key.family;
212 char str[INET6_ADDRSTRLEN];
213
214 if (!inet_ntop(family, next_key.addr, str, sizeof(str))) {
215 perror("converting IP to string:");
216 return -1;
217 }
218
219 printf("%s ", str);
220 }
221
222 if (env.extended)
223 printf("[AVG %llu]", hist.latency / hist.cnt);
224 printf("\n");
225 print_log2_hist(hist.slots, MAX_SLOTS, units);
226 lookup_key = &next_key;
227 }
228
229 lookup_key = NULL;
230 while (!bpf_map_get_next_key(fd, lookup_key, &next_key)) {
231 err = bpf_map_delete_elem(fd, &next_key);
232 if (err < 0) {
233 fprintf(stderr, "failed to cleanup infos: %d\n", err);
234 return -1;
235 }
236 lookup_key = &next_key;
237 }
238
239 return 0;
240 }
241
main(int argc,char ** argv)242 int main(int argc, char **argv)
243 {
244 static const struct argp argp = {
245 .options = opts,
246 .parser = parse_arg,
247 .doc = argp_program_doc,
248 };
249 __u8 zero_addr_v6[IPV6_LEN] = {};
250 struct tcprtt_bpf *obj;
251 __u64 time_end = 0;
252 struct tm *tm;
253 char ts[32];
254 time_t t;
255 int err;
256
257 err = argp_parse(&argp, argc, argv, 0, NULL, NULL);
258 if (err)
259 return err;
260
261 if ((env.laddr || env.raddr)
262 && (memcmp(env.laddr_v6, zero_addr_v6, sizeof(env.laddr_v6)) || memcmp(env.raddr_v6, zero_addr_v6, sizeof(env.raddr_v6)))) {
263 fprintf(stderr, "It is not permitted to filter by both IPv4 and IPv6\n");
264 return 1;
265 }
266
267 libbpf_set_print(libbpf_print_fn);
268
269 obj = tcprtt_bpf__open();
270 if (!obj) {
271 fprintf(stderr, "failed to open BPF object\n");
272 return 1;
273 }
274
275 obj->rodata->targ_laddr_hist = env.laddr_hist;
276 obj->rodata->targ_raddr_hist = env.raddr_hist;
277 obj->rodata->targ_show_ext = env.extended;
278 obj->rodata->targ_sport = env.lport;
279 obj->rodata->targ_dport = env.rport;
280 obj->rodata->targ_saddr = env.laddr;
281 obj->rodata->targ_daddr = env.raddr;
282 memcpy(obj->rodata->targ_saddr_v6, env.laddr_v6, sizeof(obj->rodata->targ_saddr_v6));
283 memcpy(obj->rodata->targ_daddr_v6, env.raddr_v6, sizeof(obj->rodata->targ_daddr_v6));
284 obj->rodata->targ_ms = env.milliseconds;
285
286 if (fentry_can_attach("tcp_rcv_established", NULL))
287 bpf_program__set_autoload(obj->progs.tcp_rcv_kprobe, false);
288 else
289 bpf_program__set_autoload(obj->progs.tcp_rcv, false);
290
291 err = tcprtt_bpf__load(obj);
292 if (err) {
293 fprintf(stderr, "failed to load BPF object: %d\n", err);
294 goto cleanup;
295 }
296
297 err = tcprtt_bpf__attach(obj);
298 if (err) {
299 fprintf(stderr, "failed to attach BPF programs: %d\n", err);
300 goto cleanup;
301 }
302
303 signal(SIGINT, sig_handler);
304
305 printf("Tracing TCP RTT");
306 if (env.duration)
307 printf(" for %ld secs.\n", env.duration);
308 else
309 printf("... Hit Ctrl-C to end.\n");
310
311 /* setup duration */
312 if (env.duration)
313 time_end = get_ktime_ns() + env.duration * NSEC_PER_SEC;
314
315 /* main: poll */
316 while (1) {
317 sleep(env.interval);
318 printf("\n");
319
320 if (env.timestamp) {
321 time(&t);
322 tm = localtime(&t);
323 strftime(ts, sizeof(ts), "%H:%M:%S", tm);
324 printf("%-8s\n", ts);
325 }
326
327 err = print_map(obj->maps.hists);
328 if (err)
329 break;
330
331 if (env.duration && get_ktime_ns() > time_end)
332 goto cleanup;
333
334 if (exiting)
335 break;
336 }
337
338 cleanup:
339 tcprtt_bpf__destroy(obj);
340 return err != 0;
341 }
342