xref: /openbsd-src/usr.sbin/tcpdump/util.c (revision 0b7734b3d77bb9b21afec6f4621cae6c805dbd45)
1 /*	$OpenBSD: util.c,v 1.27 2015/11/16 00:16:39 mmcc Exp $	*/
2 
3 /*
4  * Copyright (c) 1990, 1991, 1993, 1994, 1995, 1996, 1997
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that: (1) source code distributions
9  * retain the above copyright notice and this paragraph in its entirety, (2)
10  * distributions including binary code include the above copyright notice and
11  * this paragraph in its entirety in the documentation or other materials
12  * provided with the distribution, and (3) all advertising materials mentioning
13  * features or use of this software display the following acknowledgement:
14  * ``This product includes software developed by the University of California,
15  * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
16  * the University nor the names of its contributors may be used to endorse
17  * or promote products derived from this software without specific prior
18  * written permission.
19  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
20  * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
21  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
22  */
23 
24 #include <sys/types.h>
25 #include <sys/time.h>
26 #include <sys/file.h>
27 #include <sys/limits.h>
28 #include <sys/stat.h>
29 
30 #include <ctype.h>
31 #include <err.h>
32 #include <errno.h>
33 #ifdef HAVE_FCNTL_H
34 #include <fcntl.h>
35 #endif
36 #include <pcap.h>
37 #include <stdio.h>
38 #include <stdarg.h>
39 #include <stdlib.h>
40 #include <string.h>
41 #ifdef TIME_WITH_SYS_TIME
42 #include <time.h>
43 #endif
44 #include <unistd.h>
45 
46 #include "interface.h"
47 #include "privsep.h"
48 /*
49  * Print out a filename (or other ascii string).
50  * If ep is NULL, assume no truncation check is needed.
51  * Return true if truncated.
52  */
53 int
54 fn_print(const u_char *s, const u_char *ep)
55 {
56 	int ret;
57 	u_char c;
58 
59 	ret = 1;			/* assume truncated */
60 	while (ep == NULL || s < ep) {
61 		c = *s++;
62 		if (c == '\0') {
63 			ret = 0;
64 			break;
65 		}
66 		if (!isascii(c)) {
67 			c = toascii(c);
68 			putchar('M');
69 			putchar('-');
70 		}
71 		if (!isprint(c)) {
72 			c ^= 0x40;	/* DEL to ?, others to alpha */
73 			putchar('^');
74 		}
75 		putchar(c);
76 	}
77 	return(ret);
78 }
79 
80 /*
81  * Print out a counted filename (or other ascii string).
82  * If ep is NULL, assume no truncation check is needed.
83  * Return true if truncated.
84  */
85 int
86 fn_printn(const u_char *s, u_int n, const u_char *ep)
87 {
88 	int ret;
89 	u_char c;
90 
91 	ret = 1;			/* assume truncated */
92 	while (ep == NULL || s < ep) {
93 		if (n-- <= 0) {
94 			ret = 0;
95 			break;
96 		}
97 		c = *s++;
98 		if (!isascii(c)) {
99 			c = toascii(c);
100 			putchar('M');
101 			putchar('-');
102 		}
103 		if (!isprint(c)) {
104 			c ^= 0x40;	/* DEL to ?, others to alpha */
105 			putchar('^');
106 		}
107 		putchar(c);
108 	}
109 	return(ret);
110 }
111 
112 /*
113  * Print the timestamp
114  */
115 void
116 ts_print(const struct bpf_timeval *tvp)
117 {
118 	int s;
119 #define TSBUFLEN 32
120 	static char buf[TSBUFLEN];
121 	static struct bpf_timeval last;
122 	struct timeval diff;
123 	time_t t;
124 
125 	if (Iflag && device)
126 		(void)printf("%s ", device);
127 	switch(tflag){
128 	case 0:
129 		break;
130 	case -1:
131 		/* Unix timeval style */
132 		(void)printf("%u.%06u ",
133 		    (u_int32_t)tvp->tv_sec, (u_int32_t)tvp->tv_usec);
134 		break;
135 	case -2:
136 		t=tvp->tv_sec;
137 		strftime(buf, TSBUFLEN, "%b %d %T", priv_localtime(&t));
138 		printf("%s.%06u ", buf, (u_int32_t)tvp->tv_usec);
139 		break;
140 	case -3:
141 	case -4:
142 		/* time since first/last frame */
143 		timersub(tvp, &last, &diff);
144 		(void)printf("%u.%06u ",
145 		    (u_int32_t)diff.tv_sec, (u_int32_t)diff.tv_usec);
146 		if (tflag == -3 || (last.tv_sec == 0 && last.tv_usec == 0))
147 			last = *tvp;
148 		break;
149 	default:
150 		/* Default */
151 		s = (tvp->tv_sec + thiszone) % 86400;
152 		(void)printf("%02d:%02d:%02d.%06u ",
153 		    s / 3600, (s % 3600) / 60, s % 60, (u_int32_t)tvp->tv_usec);
154 		break;
155 	}
156 }
157 
158 /*
159  * Print a relative number of seconds (e.g. hold time, prune timer)
160  * in the form 5m1s.  This does no truncation, so 32230861 seconds
161  * is represented as 1y1w1d1h1m1s.
162  */
163 void
164 relts_print(int secs)
165 {
166 	static char *lengths[] = {"y", "w", "d", "h", "m", "s"};
167 	static int seconds[] = {31536000, 604800, 86400, 3600, 60, 1};
168 	char **l = lengths;
169 	int *s = seconds;
170 
171 	if (secs <= 0) {
172 		(void)printf("0s");
173 		return;
174 	}
175 	while (secs > 0) {
176 		if (secs >= *s) {
177 			(void)printf("%d%s", secs / *s, *l);
178 			secs -= (secs / *s) * *s;
179 		}
180 		s++;
181 		l++;
182 	}
183 }
184 
185 /*
186  * Convert a token value to a string; use "fmt" if not found.
187  */
188 const char *
189 tok2str(const struct tok *lp, const char *fmt, int v)
190 {
191 	static char buf[128];
192 
193 	while (lp->s != NULL) {
194 		if (lp->v == v)
195 			return (lp->s);
196 		++lp;
197 	}
198 	if (fmt == NULL)
199 		fmt = "#%d";
200 	(void)snprintf(buf, sizeof(buf), fmt, v);
201 	return (buf);
202 }
203 
204 
205 __dead void
206 error(const char *fmt, ...)
207 {
208 	va_list ap;
209 
210 	(void)fprintf(stderr, "%s: ", program_name);
211 	va_start(ap, fmt);
212 	(void)vfprintf(stderr, fmt, ap);
213 	va_end(ap);
214 	(void)fputc('\n', stderr);
215 	exit(1);
216 	/* NOTREACHED */
217 }
218 
219 void
220 warning(const char *fmt, ...)
221 {
222 	va_list ap;
223 
224 	(void)fprintf(stderr, "%s: WARNING: ", program_name);
225 	va_start(ap, fmt);
226 	(void)vfprintf(stderr, fmt, ap);
227 	va_end(ap);
228 	(void)fputc('\n', stderr);
229 }
230 
231 
232 /*
233  * Copy arg vector into a new buffer, concatenating arguments with spaces.
234  */
235 char *
236 copy_argv(char * const *argv)
237 {
238 	size_t len = 0, n;
239 	char *buf;
240 
241 	if (argv == NULL)
242 		return (NULL);
243 
244 	for (n = 0; argv[n]; n++)
245 		len += strlen(argv[n])+1;
246 	if (len == 0)
247 		return (NULL);
248 
249 	buf = malloc(len);
250 	if (buf == NULL)
251 		return (NULL);
252 
253 	strlcpy(buf, argv[0], len);
254 	for (n = 1; argv[n]; n++) {
255 		strlcat(buf, " ", len);
256 		strlcat(buf, argv[n], len);
257 	}
258 	return (buf);
259 }
260 
261 char *
262 read_infile(char *fname)
263 {
264 	struct stat	 buf;
265 	int		 fd;
266 	ssize_t		 cc;
267 	size_t		 bs;
268 	char		*cp;
269 
270 	fd = open(fname, O_RDONLY);
271 	if (fd < 0)
272 		error("can't open %s: %s", fname, pcap_strerror(errno));
273 
274 	if (fstat(fd, &buf) < 0)
275 		error("can't stat %s: %s", fname, pcap_strerror(errno));
276 
277 	if (buf.st_size >= SSIZE_MAX)
278 		error("file too long");
279 
280 	bs = buf.st_size;
281 	cp = malloc(bs + 1);
282 	if (cp == NULL)
283 		err(1, NULL);
284 	cc = read(fd, cp, bs);
285 	if (cc == -1)
286 		error("read %s: %s", fname, pcap_strerror(errno));
287 	if (cc != bs)
288 		error("short read %s (%ld != %lu)", fname, (long)cc,
289 		    (unsigned long)bs);
290 	cp[bs] = '\0';
291 	close(fd);
292 
293 	return (cp);
294 }
295 
296 void
297 safeputs(const char *s)
298 {
299 	while (*s) {
300 		safeputchar(*s);
301 		s++;
302 	}
303 }
304 
305 void
306 safeputchar(int c)
307 {
308 	unsigned char ch;
309 
310 	ch = (unsigned char)(c & 0xff);
311 	if (c < 0x80 && isprint(c))
312 		printf("%c", c & 0xff);
313 	else
314 		printf("\\%03o", c & 0xff);
315 }
316 
317 /*
318  * Print a value a la the %b format of the kernel's printf
319  * (from sbin/ifconfig/ifconfig.c)
320  */
321 void
322 printb(char *s, unsigned short v, char *bits)
323 {
324 	int i, any = 0;
325 	char c;
326 
327 	if (bits && *bits == 8)
328 		printf("%s=%o", s, v);
329 	else
330 		printf("%s=%x", s, v);
331 
332 	if (bits) {
333 		bits++;
334 		putchar('<');
335 		while ((i = *bits++)) {
336 			if (v & (1 << (i-1))) {
337 				if (any)
338 					putchar(',');
339 				any = 1;
340 				for (; (c = *bits) > 32; bits++)
341 					putchar(c);
342 			} else
343 				for (; *bits > 32; bits++)
344 					;
345 		}
346 		putchar('>');
347 	}
348 }
349