fix merge between onelab and princeton repositories
[iproute2.git] / misc / nstat.c
1 /*
2  * nstat.c      handy utility to read counters /proc/net/netstat and snmp
3  *
4  *              This program is free software; you can redistribute it and/or
5  *              modify it under the terms of the GNU General Public License
6  *              as published by the Free Software Foundation; either version
7  *              2 of the License, or (at your option) any later version.
8  *
9  * Authors:     Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
10  */
11
12 #include <stdio.h>
13 #include <stdlib.h>
14 #include <unistd.h>
15 #include <fcntl.h>
16 #include <string.h>
17 #include <errno.h>
18 #include <time.h>
19 #include <sys/time.h>
20 #include <fnmatch.h>
21 #include <sys/file.h>
22 #include <sys/socket.h>
23 #include <sys/un.h>
24 #include <sys/poll.h>
25 #include <sys/wait.h>
26 #include <sys/stat.h>
27 #include <signal.h>
28 #include <math.h>
29
30 #include <SNAPSHOT.h>
31
32 int dump_zeros = 0;
33 int reset_history = 0;
34 int ignore_history = 0;
35 int no_output = 0;
36 int no_update = 0;
37 int scan_interval = 0;
38 int time_constant = 0;
39 double W;
40 char **patterns;
41 int npatterns;
42
43 char info_source[128];
44 int source_mismatch;
45
46 int generic_proc_open(char *env, char *name)
47 {
48         char store[128];
49         char *p = getenv(env);
50         if (!p) {
51                 p = getenv("PROC_ROOT") ? : "/proc";
52                 snprintf(store, sizeof(store)-1, "%s/%s", p, name);
53                 p = store;
54         }
55         return open(store, O_RDONLY);
56 }
57
58 int net_netstat_open(void)
59 {
60         return generic_proc_open("PROC_NET_NETSTAT", "net/netstat");
61 }
62
63 int net_snmp_open(void)
64 {
65         return generic_proc_open("PROC_NET_SNMP", "net/snmp");
66 }
67
68 int net_snmp6_open(void)
69 {
70         return generic_proc_open("PROC_NET_SNMP6", "net/snmp6");
71 }
72
73 struct nstat_ent
74 {
75         struct nstat_ent *next;
76         char             *id;
77         unsigned long long val;
78         unsigned long      ival;
79         double             rate;
80 };
81
82 struct nstat_ent *kern_db;
83 struct nstat_ent *hist_db;
84
85 char *useless_numbers[] = {
86 "IpForwarding", "IpDefaultTTL",
87 "TcpRtoAlgorithm", "TcpRtoMin", "TcpRtoMax",
88 "TcpMaxConn", "TcpCurrEstab"
89 };
90
91 int useless_number(char *id)
92 {
93         int i;
94         for (i=0; i<sizeof(useless_numbers)/sizeof(*useless_numbers); i++)
95                 if (strcmp(id, useless_numbers[i]) == 0)
96                         return 1;
97         return 0;
98 }
99
100 int match(char *id)
101 {
102         int i;
103
104         if (npatterns == 0)
105                 return 1;
106
107         for (i=0; i<npatterns; i++) {
108                 if (!fnmatch(patterns[i], id, 0))
109                         return 1;
110         }
111         return 0;
112 }
113
114 void load_good_table(FILE *fp)
115 {
116         char buf[4096];
117         struct nstat_ent *db = NULL;
118         struct nstat_ent *n;
119
120         while (fgets(buf, sizeof(buf), fp) != NULL) {
121                 int nr;
122                 unsigned long long val;
123                 double rate;
124                 char idbuf[sizeof(buf)];
125                 if (buf[0] == '#') {
126                         buf[strlen(buf)-1] = 0;
127                         if (info_source[0] && strcmp(info_source, buf+1))
128                                 source_mismatch = 1;
129                         info_source[0] = 0;
130                         strncat(info_source, buf+1, sizeof(info_source)-1);
131                         continue;
132                 }
133                 /* idbuf is as big as buf, so this is safe */
134                 nr = sscanf(buf, "%s%llu%lg", idbuf, &val, &rate);
135                 if (nr < 2)
136                         abort();
137                 if (nr < 3)
138                         rate = 0;
139                 if (useless_number(idbuf))
140                         continue;
141                 if ((n = malloc(sizeof(*n))) == NULL)
142                         abort();
143                 n->id = strdup(idbuf);
144                 n->ival = (unsigned long)val;
145                 n->val = val;
146                 n->rate = rate;
147                 n->next = db;
148                 db = n;
149         }
150
151         while (db) {
152                 n = db;
153                 db = db->next;
154                 n->next = kern_db;
155                 kern_db = n;
156         }
157 }
158
159
160 void load_ugly_table(FILE *fp)
161 {
162         char buf[4096];
163         struct nstat_ent *db = NULL;
164         struct nstat_ent *n;
165
166         while (fgets(buf, sizeof(buf), fp) != NULL) {
167                 char idbuf[sizeof(buf)];
168                 int  off;
169                 char *p;
170
171                 p = strchr(buf, ':');
172                 if (!p)
173                         abort();
174                 *p = 0;
175                 idbuf[0] = 0;
176                 strncat(idbuf, buf, sizeof(idbuf) - 1);
177                 off = p - buf;
178                 p += 2;
179
180                 while (*p) {
181                         char *next;
182                         if ((next = strchr(p, ' ')) != NULL)
183                                 *next++ = 0;
184                         else if ((next = strchr(p, '\n')) != NULL)
185                                 *next++ = 0;
186                         if (off < sizeof(idbuf)) {
187                                 idbuf[off] = 0;
188                                 strncat(idbuf, p, sizeof(idbuf) - off - 1);
189                         }
190                         n = malloc(sizeof(*n));
191                         if (!n)
192                                 abort();
193                         n->id = strdup(idbuf);
194                         n->rate = 0;
195                         n->next = db;
196                         db = n;
197                         p = next;
198                 }
199                 n = db;
200                 if (fgets(buf, sizeof(buf), fp) == NULL)
201                         abort();
202                 do {
203                         p = strrchr(buf, ' ');
204                         if (!p)
205                                 abort();
206                         *p = 0;
207                         if (sscanf(p+1, "%lu", &n->ival) != 1)
208                                 abort();
209                         n->val = n->ival;
210                         /* Trick to skip "dummy" trailing ICMP MIB in 2.4 */
211                         if (strcmp(idbuf, "IcmpOutAddrMaskReps") == 0)
212                                 idbuf[5] = 0;
213                         else
214                                 n = n->next;
215                 } while (p > buf + off + 2);
216         }
217
218         while (db) {
219                 n = db;
220                 db = db->next;
221                 if (useless_number(n->id)) {
222                         free(n->id);
223                         free(n);
224                 } else {
225                         n->next = kern_db;
226                         kern_db = n;
227                 }
228         }
229 }
230
231 void load_snmp(void)
232 {
233         FILE *fp = fdopen(net_snmp_open(), "r");
234         if (fp) {
235                 load_ugly_table(fp);
236                 fclose(fp);
237         }
238 }
239
240 void load_snmp6(void)
241 {
242         FILE *fp = fdopen(net_snmp6_open(), "r");
243         if (fp) {
244                 load_good_table(fp);
245                 fclose(fp);
246         }
247 }
248
249 void load_netstat(void)
250 {
251         FILE *fp = fdopen(net_netstat_open(), "r");
252         if (fp) {
253                 load_ugly_table(fp);
254                 fclose(fp);
255         }
256 }
257
258 void dump_kern_db(FILE *fp, int to_hist)
259 {
260         struct nstat_ent *n, *h;
261         h = hist_db;
262         fprintf(fp, "#%s\n", info_source);
263         for (n=kern_db; n; n=n->next) {
264                 unsigned long long val = n->val;
265                 if (!dump_zeros && !val && !n->rate)
266                         continue;
267                 if (!match(n->id)) {
268                         struct nstat_ent *h1;
269                         if (!to_hist)
270                                 continue;
271                         for (h1 = h; h1; h1 = h1->next) {
272                                 if (strcmp(h1->id, n->id) == 0) {
273                                         val = h1->val;
274                                         h = h1->next;
275                                         break;
276                                 }
277                         }
278                 }
279                 fprintf(fp, "%-32s%-16llu%6.1f\n", n->id, val, n->rate);
280         }
281 }
282
283 void dump_incr_db(FILE *fp)
284 {
285         struct nstat_ent *n, *h;
286         h = hist_db;
287         fprintf(fp, "#%s\n", info_source);
288         for (n=kern_db; n; n=n->next) {
289                 int ovfl = 0;
290                 unsigned long long val = n->val;
291                 struct nstat_ent *h1;
292                 for (h1 = h; h1; h1 = h1->next) {
293                         if (strcmp(h1->id, n->id) == 0) {
294                                 if (val < h1->val) {
295                                         ovfl = 1;
296                                         val = h1->val;
297                                 }
298                                 val -= h1->val;
299                                 h = h1->next;
300                                 break;
301                         }
302                 }
303                 if (!dump_zeros && !val && !n->rate)
304                         continue;
305                 if (!match(n->id))
306                         continue;
307                 fprintf(fp, "%-32s%-16llu%6.1f%s\n", n->id, val,
308                         n->rate, ovfl?" (overflow)":"");
309         }
310 }
311
312 static int children;
313
314 void sigchild(int signo)
315 {
316 }
317
318 void update_db(int interval)
319 {
320         struct nstat_ent *n, *h;
321
322         n = kern_db;
323         kern_db = NULL;
324
325         load_netstat();
326         load_snmp6();
327         load_snmp();
328
329         h = kern_db;
330         kern_db = n;
331
332         for (n = kern_db; n; n = n->next) {
333                 struct nstat_ent *h1;
334                 for (h1 = h; h1; h1 = h1->next) {
335                         if (strcmp(h1->id, n->id) == 0) {
336                                 double sample;
337                                 unsigned long incr = h1->ival - n->ival;
338                                 n->val += incr;
339                                 n->ival = h1->ival;
340                                 sample = (double)(incr*1000)/interval;
341                                 if (interval >= scan_interval) {
342                                         n->rate += W*(sample-n->rate);
343                                 } else if (interval >= 1000) {
344                                         if (interval >= time_constant) {
345                                                 n->rate = sample;
346                                         } else {
347                                                 double w = W*(double)interval/scan_interval;
348                                                 n->rate += w*(sample-n->rate);
349                                         }
350                                 }
351
352                                 while (h != h1) {
353                                         struct nstat_ent *tmp = h;
354                                         h = h->next;
355                                         free(tmp->id);
356                                         free(tmp);
357                                 };
358                                 h = h1->next;
359                                 free(h1->id);
360                                 free(h1);
361                                 break;
362                         }
363                 }
364         }
365 }
366
367 #define T_DIFF(a,b) (((a).tv_sec-(b).tv_sec)*1000 + ((a).tv_usec-(b).tv_usec)/1000)
368
369
370 void server_loop(int fd)
371 {
372         struct timeval snaptime = { 0 };
373         struct pollfd p;
374         p.fd = fd;
375         p.events = p.revents = POLLIN;
376         
377         sprintf(info_source, "%d.%lu sampling_interval=%d time_const=%d",
378                 getpid(), (unsigned long)random(), scan_interval/1000, time_constant/1000);
379
380         load_netstat();
381         load_snmp6();
382         load_snmp();
383
384         for (;;) {
385                 int status;
386                 int tdiff;
387                 struct timeval now;
388                 gettimeofday(&now, NULL);
389                 tdiff = T_DIFF(now, snaptime);
390                 if (tdiff >= scan_interval) {
391                         update_db(tdiff);
392                         snaptime = now;
393                         tdiff = 0;
394                 }
395                 if (poll(&p, 1, tdiff + scan_interval) > 0
396                     && (p.revents&POLLIN)) {
397                         int clnt = accept(fd, NULL, NULL);
398                         if (clnt >= 0) {
399                                 pid_t pid;
400                                 if (children >= 5) {
401                                         close(clnt);
402                                 } else if ((pid = fork()) != 0) {
403                                         if (pid>0)
404                                                 children++;
405                                         close(clnt);
406                                 } else {
407                                         FILE *fp = fdopen(clnt, "w");
408                                         if (fp) {
409                                                 if (tdiff > 0)
410                                                         update_db(tdiff);
411                                                 dump_kern_db(fp, 0);
412                                         }
413                                         exit(0);
414                                 }
415                         }
416                 }
417                 while (children && waitpid(-1, &status, WNOHANG) > 0)
418                         children--;
419         }
420 }
421
422 int verify_forging(int fd)
423 {
424         struct ucred cred;
425         socklen_t olen = sizeof(cred);
426
427         if (getsockopt(fd, SOL_SOCKET, SO_PEERCRED, (void*)&cred, &olen) ||
428             olen < sizeof(cred))
429                 return -1;
430         if (cred.uid == getuid() || cred.uid == 0)
431                 return 0;
432         return -1;
433 }
434
435 static void usage(void) __attribute__((noreturn));
436
437 static void usage(void)
438 {
439         fprintf(stderr,
440 "Usage: nstat [ -h?vVzrnasd:t: ] [ PATTERN [ PATTERN ] ]\n"
441                 );
442         exit(-1);
443 }
444
445
446 int main(int argc, char *argv[])
447 {
448         char hist_name[128];
449         struct sockaddr_un sun;
450         FILE *hist_fp = NULL;
451         int ch;
452         int fd;
453
454         while ((ch = getopt(argc, argv, "h?vVzrnasd:t:")) != EOF) {
455                 switch(ch) {
456                 case 'z':
457                         dump_zeros = 1;
458                         break;
459                 case 'r':
460                         reset_history = 1;
461                         break;
462                 case 'a':
463                         ignore_history = 1;
464                         break;
465                 case 's':
466                         no_update = 1;
467                         break;
468                 case 'n':
469                         no_output = 1;
470                         break;
471                 case 'd':
472                         scan_interval = 1000*atoi(optarg);
473                         break;
474                 case 't':
475                         if (sscanf(optarg, "%d", &time_constant) != 1 ||
476                             time_constant <= 0) {
477                                 fprintf(stderr, "nstat: invalid time constant divisor\n");
478                                 exit(-1);
479                         }
480                         break;
481                 case 'v':
482                 case 'V':
483                         printf("nstat utility, iproute2-ss%s\n", SNAPSHOT);
484                         exit(0);
485                 case 'h':
486                 case '?':
487                 default:
488                         usage();
489                 }
490         }
491
492         argc -= optind;
493         argv += optind;
494
495         sun.sun_family = AF_UNIX;
496         sun.sun_path[0] = 0;
497         sprintf(sun.sun_path+1, "nstat%d", getuid());
498
499         if (scan_interval > 0) {
500                 if (time_constant == 0)
501                         time_constant = 60;
502                 time_constant *= 1000;
503                 W = 1 - 1/exp(log(10)*(double)scan_interval/time_constant);
504                 if ((fd = socket(AF_UNIX, SOCK_STREAM, 0)) < 0) {
505                         perror("nstat: socket");
506                         exit(-1);
507                 }
508                 if (bind(fd, (struct sockaddr*)&sun, 2+1+strlen(sun.sun_path+1)) < 0) {
509                         perror("nstat: bind");
510                         exit(-1);
511                 }
512                 if (listen(fd, 5) < 0) {
513                         perror("nstat: listen");
514                         exit(-1);
515                 }
516                 if (fork())
517                         exit(0);
518                 chdir("/");
519                 close(0); close(1); close(2); setsid();
520                 signal(SIGPIPE, SIG_IGN);
521                 signal(SIGCHLD, sigchild);
522                 server_loop(fd);
523                 exit(0);
524         }
525
526         patterns = argv;
527         npatterns = argc;
528
529         if (getenv("NSTAT_HISTORY"))
530                 snprintf(hist_name, sizeof(hist_name), getenv("NSTAT_HISTORY"));
531         else
532                 sprintf(hist_name, "/tmp/.nstat.u%d", getuid());
533
534         if (reset_history)
535                 unlink(hist_name);
536
537         if (!ignore_history || !no_update) {
538                 struct stat stb;
539
540                 fd = open(hist_name, O_RDWR|O_CREAT|O_NOFOLLOW, 0600);
541                 if (fd < 0) {
542                         perror("nstat: open history file");
543                         exit(-1);
544                 }
545                 if ((hist_fp = fdopen(fd, "r+")) == NULL) {
546                         perror("nstat: fdopen history file");
547                         exit(-1);
548                 }
549                 if (flock(fileno(hist_fp), LOCK_EX)) {
550                         perror("nstat: flock history file");
551                         exit(-1);
552                 }
553                 if (fstat(fileno(hist_fp), &stb) != 0) {
554                         perror("nstat: fstat history file");
555                         exit(-1);
556                 }
557                 if (stb.st_nlink != 1 || stb.st_uid != getuid()) {
558                         fprintf(stderr, "nstat: something is so wrong with history file, that I prefer not to proceed.\n");
559                         exit(-1);
560                 }
561                 if (!ignore_history) {
562                         FILE *tfp;
563                         long uptime;
564                         if ((tfp = fopen("/proc/uptime", "r")) != NULL) {
565                                 if (fscanf(tfp, "%ld", &uptime) != 1)
566                                         uptime = -1;
567                                 fclose(tfp);
568                         }
569                         if (uptime >= 0 && time(NULL) >= stb.st_mtime+uptime) {
570                                 fprintf(stderr, "nstat: history is aged out, resetting\n");
571                                 ftruncate(fileno(hist_fp), 0);
572                         }
573                 }
574
575                 load_good_table(hist_fp);
576
577                 hist_db = kern_db;
578                 kern_db = NULL;
579         }
580
581         if ((fd = socket(AF_UNIX, SOCK_STREAM, 0)) >= 0 &&
582             (connect(fd, (struct sockaddr*)&sun, 2+1+strlen(sun.sun_path+1)) == 0
583              || (strcpy(sun.sun_path+1, "nstat0"),
584                  connect(fd, (struct sockaddr*)&sun, 2+1+strlen(sun.sun_path+1)) == 0))
585             && verify_forging(fd) == 0) {
586                 FILE *sfp = fdopen(fd, "r");
587                 load_good_table(sfp);
588                 if (hist_db && source_mismatch) {
589                         fprintf(stderr, "nstat: history is stale, ignoring it.\n");
590                         hist_db = NULL;
591                 }
592                 fclose(sfp);
593         } else {
594                 if (fd >= 0)
595                         close(fd);
596                 if (hist_db && info_source[0] && strcmp(info_source, "kernel")) {
597                         fprintf(stderr, "nstat: history is stale, ignoring it.\n");
598                         hist_db = NULL;
599                         info_source[0] = 0;
600                 }
601                 load_netstat();
602                 load_snmp6();
603                 load_snmp();
604                 if (info_source[0] == 0)
605                         strcpy(info_source, "kernel");
606         }
607
608         if (!no_output) {
609                 if (ignore_history || hist_db == NULL)
610                         dump_kern_db(stdout, 0);
611                 else
612                         dump_incr_db(stdout);
613         }
614         if (!no_update) {
615                 ftruncate(fileno(hist_fp), 0);
616                 rewind(hist_fp);
617                 dump_kern_db(hist_fp, 1);
618                 fflush(hist_fp);
619         }
620         exit(0);
621 }