1/*
2 * rtacct.c		Applet to display contents of /proc/net/rt_acct.
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
13#include <stdio.h>
14#include <stdlib.h>
15#include <unistd.h>
16#include <fcntl.h>
17#include <string.h>
18#include <errno.h>
19#include <time.h>
20#include <sys/time.h>
21#include <fnmatch.h>
22#include <sys/file.h>
23#include <sys/socket.h>
24#include <sys/un.h>
25#include <sys/poll.h>
26#include <sys/wait.h>
27#include <sys/stat.h>
28#include <sys/mman.h>
29#include <signal.h>
30#include <math.h>
31
32#include "rt_names.h"
33
34#include <SNAPSHOT.h>
35
36int reset_history = 0;
37int ignore_history = 0;
38int no_output = 0;
39int no_update = 0;
40int scan_interval = 0;
41int time_constant = 0;
42int dump_zeros = 0;
43unsigned long magic_number = 0;
44double W;
45
46static int generic_proc_open(const char *env, const char *name)
47{
48	char store[1024];
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(p, O_RDONLY);
56}
57
58int net_rtacct_open(void)
59{
60	return generic_proc_open("PROC_NET_RTACCT", "net/rt_acct");
61}
62
63__u32 rmap[256/4];
64
65struct rtacct_data
66{
67	__u32			ival[256*4];
68
69	unsigned long long	val[256*4];
70	double			rate[256*4];
71	char			signature[128];
72};
73
74struct rtacct_data kern_db_static;
75
76struct rtacct_data *kern_db = &kern_db_static;
77struct rtacct_data *hist_db;
78
79void nread(int fd, char *buf, int tot)
80{
81	int count = 0;
82
83	while (count < tot) {
84		int n = read(fd, buf+count, tot-count);
85		if (n < 0) {
86			if (errno == EINTR)
87				continue;
88			exit(-1);
89		}
90		if (n == 0)
91			exit(-1);
92		count += n;
93	}
94}
95
96
97__u32 *read_kern_table(__u32 *tbl)
98{
99	static __u32 *tbl_ptr;
100	int fd;
101
102	if (magic_number) {
103		if (tbl_ptr != NULL)
104			return tbl_ptr;
105
106		fd = open("/dev/mem", O_RDONLY);
107		if (fd < 0) {
108			perror("magic open");
109			exit(-1);
110		}
111		tbl_ptr = mmap(NULL, 4096,
112			       PROT_READ,
113			       MAP_SHARED,
114			       fd, magic_number);
115		if ((unsigned long)tbl_ptr == ~0UL) {
116			perror("magic mmap");
117			exit(-1);
118		}
119		close(fd);
120		return tbl_ptr;
121	}
122
123	fd = net_rtacct_open();
124	if (fd >= 0) {
125		nread(fd, (char*)tbl, 256*16);
126		close(fd);
127	} else {
128		memset(tbl, 0, 256*16);
129	}
130	return tbl;
131}
132
133void format_rate(FILE *fp, double rate)
134{
135	char temp[64];
136
137	if (rate > 1024*1024) {
138		sprintf(temp, "%uM", (unsigned)rint(rate/(1024*1024)));
139		fprintf(fp, " %-10s", temp);
140	} else if (rate > 1024) {
141		sprintf(temp, "%uK", (unsigned)rint(rate/1024));
142		fprintf(fp, " %-10s", temp);
143	} else
144		fprintf(fp, " %-10u", (unsigned)rate);
145}
146
147void format_count(FILE *fp, unsigned long long val)
148{
149	if (val > 1024*1024*1024)
150		fprintf(fp, " %10lluM", val/(1024*1024));
151	else if (val > 1024*1024)
152		fprintf(fp, " %10lluK", val/1024);
153	else
154		fprintf(fp, " %10llu", val);
155}
156
157void dump_abs_db(FILE *fp)
158{
159	int realm;
160	char b1[16];
161
162	if (!no_output) {
163		fprintf(fp, "#%s\n", kern_db->signature);
164		fprintf(fp,
165"%-10s "
166"%-10s "
167"%-10s "
168"%-10s "
169"%-10s "
170"\n"
171		       , "Realm", "BytesTo", "PktsTo", "BytesFrom", "PktsFrom");
172		fprintf(fp,
173"%-10s "
174"%-10s "
175"%-10s "
176"%-10s "
177"%-10s "
178"\n"
179		       , "", "BPSTo", "PPSTo", "BPSFrom", "PPSFrom");
180
181	}
182
183	for (realm=0; realm<256; realm++) {
184		int i;
185		unsigned long long *val;
186		double		   *rate;
187
188		if (!(rmap[realm>>5] & (1<<(realm&0x1f))))
189			continue;
190
191		val = &kern_db->val[realm*4];
192		rate = &kern_db->rate[realm*4];
193
194		if (!dump_zeros &&
195		    !val[0] && !rate[0] &&
196		    !val[1] && !rate[1] &&
197		    !val[2] && !rate[2] &&
198		    !val[3] && !rate[3])
199			continue;
200
201		if (hist_db) {
202			memcpy(&hist_db->val[realm*4], val, sizeof(*val)*4);
203		}
204
205		if (no_output)
206			continue;
207
208		fprintf(fp, "%-10s", rtnl_rtrealm_n2a(realm, b1, sizeof(b1)));
209		for (i = 0; i < 4; i++)
210			format_count(fp, val[i]);
211		fprintf(fp, "\n%-10s", "");
212		for (i = 0; i < 4; i++)
213			format_rate(fp, rate[i]);
214		fprintf(fp, "\n");
215	}
216}
217
218
219void dump_incr_db(FILE *fp)
220{
221	int k, realm;
222	char b1[16];
223
224	if (!no_output) {
225		fprintf(fp, "#%s\n", kern_db->signature);
226		fprintf(fp,
227"%-10s "
228"%-10s "
229"%-10s "
230"%-10s "
231"%-10s "
232"\n"
233		       , "Realm", "BytesTo", "PktsTo", "BytesFrom", "PktsFrom");
234		fprintf(fp,
235"%-10s "
236"%-10s "
237"%-10s "
238"%-10s "
239"%-10s "
240"\n"
241		       , "", "BPSTo", "PPSTo", "BPSFrom", "PPSFrom");
242	}
243
244	for (realm=0; realm<256; realm++) {
245		int ovfl = 0;
246		int i;
247		unsigned long long *val;
248		double		   *rate;
249		unsigned long long rval[4];
250
251		if (!(rmap[realm>>5] & (1<<(realm&0x1f))))
252			continue;
253
254		val = &kern_db->val[realm*4];
255		rate = &kern_db->rate[realm*4];
256
257		for (k=0; k<4; k++) {
258			rval[k] = val[k];
259			if (rval[k] < hist_db->val[realm*4+k])
260				ovfl = 1;
261			else
262				rval[k] -= hist_db->val[realm*4+k];
263		}
264		if (ovfl) {
265			for (k=0; k<4; k++)
266				rval[k] = val[k];
267		}
268		if (hist_db) {
269			memcpy(&hist_db->val[realm*4], val, sizeof(*val)*4);
270		}
271
272		if (no_output)
273			continue;
274
275		if (!dump_zeros &&
276		    !rval[0] && !rate[0] &&
277		    !rval[1] && !rate[1] &&
278		    !rval[2] && !rate[2] &&
279		    !rval[3] && !rate[3])
280			continue;
281
282
283		fprintf(fp, "%-10s", rtnl_rtrealm_n2a(realm, b1, sizeof(b1)));
284		for (i = 0; i < 4; i++)
285			format_count(fp, rval[i]);
286		fprintf(fp, "\n%-10s", "");
287		for (i = 0; i < 4; i++)
288			format_rate(fp, rate[i]);
289		fprintf(fp, "\n");
290	}
291}
292
293
294static int children;
295
296void sigchild(int signo)
297{
298}
299
300/* Server side only: read kernel data, update tables, calculate rates. */
301
302void update_db(int interval)
303{
304	int i;
305	__u32 *ival;
306	__u32 _ival[256*4];
307
308	ival = read_kern_table(_ival);
309
310	for (i=0; i<256*4; i++) {
311		double sample;
312		__u32 incr = ival[i] - kern_db->ival[i];
313
314		if (ival[i] == 0 && incr == 0 &&
315		    kern_db->val[i] == 0 && kern_db->rate[i] == 0)
316			continue;
317
318		kern_db->val[i] += incr;
319		kern_db->ival[i] = ival[i];
320		sample = (double)(incr*1000)/interval;
321		if (interval >= scan_interval) {
322			kern_db->rate[i] += W*(sample-kern_db->rate[i]);
323		} else if (interval >= 1000) {
324			if (interval >= time_constant) {
325				kern_db->rate[i] = sample;
326			} else {
327				double w = W*(double)interval/scan_interval;
328				kern_db->rate[i] += w*(sample-kern_db->rate[i]);
329			}
330		}
331	}
332}
333
334void send_db(int fd)
335{
336	int tot = 0;
337
338	while (tot < sizeof(*kern_db)) {
339		int n = write(fd, ((char*)kern_db) + tot, sizeof(*kern_db)-tot);
340		if (n < 0) {
341			if (errno == EINTR)
342				continue;
343			return;
344		}
345		tot += n;
346	}
347}
348
349
350
351#define T_DIFF(a,b) (((a).tv_sec-(b).tv_sec)*1000 + ((a).tv_usec-(b).tv_usec)/1000)
352
353
354void pad_kern_table(struct rtacct_data *dat, __u32 *ival)
355{
356	int i;
357	memset(dat->rate, 0, sizeof(dat->rate));
358	if (dat->ival != ival)
359		memcpy(dat->ival, ival, sizeof(dat->ival));
360	for (i=0; i<256*4; i++)
361		dat->val[i] = ival[i];
362}
363
364void server_loop(int fd)
365{
366	struct timeval snaptime = { 0 };
367	struct pollfd p;
368	p.fd = fd;
369	p.events = p.revents = POLLIN;
370
371	sprintf(kern_db->signature,
372		"%u.%lu sampling_interval=%d time_const=%d",
373		(unsigned) getpid(), (unsigned long)random(),
374		scan_interval/1000, time_constant/1000);
375
376	pad_kern_table(kern_db, read_kern_table(kern_db->ival));
377
378	for (;;) {
379		int status;
380		int tdiff;
381		struct timeval now;
382		gettimeofday(&now, NULL);
383		tdiff = T_DIFF(now, snaptime);
384		if (tdiff >= scan_interval) {
385			update_db(tdiff);
386			snaptime = now;
387			tdiff = 0;
388		}
389		if (poll(&p, 1, tdiff + scan_interval) > 0
390		    && (p.revents&POLLIN)) {
391			int clnt = accept(fd, NULL, NULL);
392			if (clnt >= 0) {
393				pid_t pid;
394				if (children >= 5) {
395					close(clnt);
396				} else if ((pid = fork()) != 0) {
397					if (pid>0)
398						children++;
399					close(clnt);
400				} else {
401					if (tdiff > 0)
402						update_db(tdiff);
403					send_db(clnt);
404					exit(0);
405				}
406			}
407		}
408		while (children && waitpid(-1, &status, WNOHANG) > 0)
409			children--;
410	}
411}
412
413int verify_forging(int fd)
414{
415	struct ucred cred;
416	socklen_t olen = sizeof(cred);
417
418	if (getsockopt(fd, SOL_SOCKET, SO_PEERCRED, (void*)&cred, &olen) ||
419	    olen < sizeof(cred))
420		return -1;
421	if (cred.uid == getuid() || cred.uid == 0)
422		return 0;
423	return -1;
424}
425
426static void usage(void) __attribute__((noreturn));
427
428static void usage(void)
429{
430	fprintf(stderr,
431"Usage: rtacct [ -h?vVzrnasd:t: ] [ ListOfRealms ]\n"
432		);
433	exit(-1);
434}
435
436int main(int argc, char *argv[])
437{
438	char hist_name[128];
439	struct sockaddr_un sun;
440	int ch;
441	int fd;
442
443	while ((ch = getopt(argc, argv, "h?vVzrM:nasd:t:")) != EOF) {
444		switch(ch) {
445		case 'z':
446			dump_zeros = 1;
447			break;
448		case 'r':
449			reset_history = 1;
450			break;
451		case 'a':
452			ignore_history = 1;
453			break;
454		case 's':
455			no_update = 1;
456			break;
457		case 'n':
458			no_output = 1;
459			break;
460		case 'd':
461			scan_interval = 1000*atoi(optarg);
462			break;
463		case 't':
464			if (sscanf(optarg, "%d", &time_constant) != 1 ||
465			    time_constant <= 0) {
466				fprintf(stderr, "rtacct: invalid time constant divisor\n");
467				exit(-1);
468			}
469			break;
470		case 'v':
471		case 'V':
472			printf("rtacct utility, iproute2-ss%s\n", SNAPSHOT);
473			exit(0);
474		case 'M':
475			/* Some secret undocumented option, nobody
476			 * is expected to ask about its sense. See?
477			 */
478			sscanf(optarg, "%lx", &magic_number);
479			break;
480		case 'h':
481		case '?':
482		default:
483			usage();
484		}
485	}
486
487	argc -= optind;
488	argv += optind;
489
490	if (argc) {
491		while (argc > 0) {
492			__u32 realm;
493			if (rtnl_rtrealm_a2n(&realm, argv[0])) {
494				fprintf(stderr, "Warning: realm \"%s\" does not exist.\n", argv[0]);
495				exit(-1);
496			}
497			rmap[realm>>5] |= (1<<(realm&0x1f));
498			argc--; argv++;
499		}
500	} else {
501		memset(rmap, ~0, sizeof(rmap));
502		/* Always suppress zeros. */
503		dump_zeros = 0;
504	}
505
506	sun.sun_family = AF_UNIX;
507	sun.sun_path[0] = 0;
508	sprintf(sun.sun_path+1, "rtacct%d", getuid());
509
510	if (scan_interval > 0) {
511		if (time_constant == 0)
512			time_constant = 60;
513		time_constant *= 1000;
514		W = 1 - 1/exp(log(10)*(double)scan_interval/time_constant);
515		if ((fd = socket(AF_UNIX, SOCK_STREAM, 0)) < 0) {
516			perror("rtacct: socket");
517			exit(-1);
518		}
519		if (bind(fd, (struct sockaddr*)&sun, 2+1+strlen(sun.sun_path+1)) < 0) {
520			perror("rtacct: bind");
521			exit(-1);
522		}
523		if (listen(fd, 5) < 0) {
524			perror("rtacct: listen");
525			exit(-1);
526		}
527		if (daemon(0, 0)) {
528			perror("rtacct: daemon");
529			exit(-1);
530		}
531		signal(SIGPIPE, SIG_IGN);
532		signal(SIGCHLD, sigchild);
533		server_loop(fd);
534		exit(0);
535	}
536
537	if (getenv("RTACCT_HISTORY"))
538		snprintf(hist_name, sizeof(hist_name), getenv("RTACCT_HISTORY"));
539	else
540		sprintf(hist_name, "/tmp/.rtacct.u%d", getuid());
541
542	if (reset_history)
543		unlink(hist_name);
544
545	if (!ignore_history || !no_update) {
546		struct stat stb;
547
548		fd = open(hist_name, O_RDWR|O_CREAT|O_NOFOLLOW, 0600);
549		if (fd < 0) {
550			perror("rtacct: open history file");
551			exit(-1);
552		}
553		if (flock(fd, LOCK_EX)) {
554			perror("rtacct: flock history file");
555			exit(-1);
556		}
557		if (fstat(fd, &stb) != 0) {
558			perror("rtacct: fstat history file");
559			exit(-1);
560		}
561		if (stb.st_nlink != 1 || stb.st_uid != getuid()) {
562			fprintf(stderr, "rtacct: something is so wrong with history file, that I prefer not to proceed.\n");
563			exit(-1);
564		}
565		if (stb.st_size != sizeof(*hist_db))
566			write(fd, kern_db, sizeof(*hist_db));
567
568		hist_db = mmap(NULL, sizeof(*hist_db),
569			       PROT_READ|PROT_WRITE,
570			       no_update ? MAP_PRIVATE : MAP_SHARED,
571			       fd, 0);
572
573		if ((unsigned long)hist_db == ~0UL) {
574			perror("mmap");
575			exit(-1);
576		}
577
578		if (!ignore_history) {
579			FILE *tfp;
580			long uptime;
581			if ((tfp = fopen("/proc/uptime", "r")) != NULL) {
582				if (fscanf(tfp, "%ld", &uptime) != 1)
583					uptime = -1;
584				fclose(tfp);
585			}
586
587			if (uptime >= 0 && time(NULL) >= stb.st_mtime+uptime) {
588				fprintf(stderr, "rtacct: history is aged out, resetting\n");
589				memset(hist_db, 0, sizeof(*hist_db));
590			}
591		}
592
593		close(fd);
594	}
595
596	if ((fd = socket(AF_UNIX, SOCK_STREAM, 0)) >= 0 &&
597	    (connect(fd, (struct sockaddr*)&sun, 2+1+strlen(sun.sun_path+1)) == 0
598	     || (strcpy(sun.sun_path+1, "rtacct0"),
599		 connect(fd, (struct sockaddr*)&sun, 2+1+strlen(sun.sun_path+1)) == 0))
600	    && verify_forging(fd) == 0) {
601		nread(fd, (char*)kern_db, sizeof(*kern_db));
602		if (hist_db && hist_db->signature[0] &&
603		    strcmp(kern_db->signature, hist_db->signature)) {
604			fprintf(stderr, "rtacct: history is stale, ignoring it.\n");
605			hist_db = NULL;
606		}
607		close(fd);
608	} else {
609		if (fd >= 0)
610			close(fd);
611
612		if (hist_db && hist_db->signature[0] &&
613		    strcmp(hist_db->signature, "kernel")) {
614			fprintf(stderr, "rtacct: history is stale, ignoring it.\n");
615			hist_db = NULL;
616		}
617
618		pad_kern_table(kern_db, read_kern_table(kern_db->ival));
619		strcpy(kern_db->signature, "kernel");
620	}
621
622	if (ignore_history || hist_db == NULL)
623		dump_abs_db(stdout);
624	else
625		dump_incr_db(stdout);
626
627	exit(0);
628}
629