xref: /freebsd/contrib/tcpdump/util-print.c (revision ee67461e)
1 /*
2  * Copyright (c) 1990, 1991, 1993, 1994, 1995, 1996, 1997
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that: (1) source code distributions
7  * retain the above copyright notice and this paragraph in its entirety, (2)
8  * distributions including binary code include the above copyright notice and
9  * this paragraph in its entirety in the documentation or other materials
10  * provided with the distribution, and (3) all advertising materials mentioning
11  * features or use of this software display the following acknowledgement:
12  * ``This product includes software developed by the University of California,
13  * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
14  * the University nor the names of its contributors may be used to endorse
15  * or promote products derived from this software without specific prior
16  * written permission.
17  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
18  * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
19  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
20  */
21 
22 /*
23  * txtproto_print() derived from original code by Hannes Gredler
24  * (hannes@gredler.at):
25  *
26  * Redistribution and use in source and binary forms, with or without
27  * modification, are permitted provided that: (1) source code
28  * distributions retain the above copyright notice and this paragraph
29  * in its entirety, and (2) distributions including binary code include
30  * the above copyright notice and this paragraph in its entirety in
31  * the documentation or other materials provided with the distribution.
32  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND
33  * WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, WITHOUT
34  * LIMITATION, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
35  * FOR A PARTICULAR PURPOSE.
36  */
37 
38 #ifdef HAVE_CONFIG_H
39 #include <config.h>
40 #endif
41 
42 #include "netdissect-stdinc.h"
43 
44 #include <sys/stat.h>
45 
46 #ifdef HAVE_FCNTL_H
47 #include <fcntl.h>
48 #endif
49 #include <stdio.h>
50 #include <stdarg.h>
51 #include <stdlib.h>
52 #include <string.h>
53 
54 #include "netdissect-ctype.h"
55 
56 #include "netdissect.h"
57 #include "extract.h"
58 #include "ascii_strcasecmp.h"
59 #include "timeval-operations.h"
60 
61 #define TOKBUFSIZE 128
62 
63 enum date_flag { WITHOUT_DATE = 0, WITH_DATE = 1 };
64 enum time_flag { UTC_TIME = 0, LOCAL_TIME = 1 };
65 
66 /*
67  * Print out a character, filtering out the non-printable ones
68  */
69 void
fn_print_char(netdissect_options * ndo,u_char c)70 fn_print_char(netdissect_options *ndo, u_char c)
71 {
72 	if (!ND_ISASCII(c)) {
73 		c = ND_TOASCII(c);
74 		ND_PRINT("M-");
75 	}
76 	if (!ND_ASCII_ISPRINT(c)) {
77 		c ^= 0x40;	/* DEL to ?, others to alpha */
78 		ND_PRINT("^");
79 	}
80 	ND_PRINT("%c", c);
81 }
82 
83 /*
84  * Print a null-terminated string, filtering out non-printable characters.
85  * DON'T USE IT with a pointer on the packet buffer because there is no
86  * truncation check. For this use, see the nd_printX() functions below.
87  */
88 void
fn_print_str(netdissect_options * ndo,const u_char * s)89 fn_print_str(netdissect_options *ndo, const u_char *s)
90 {
91 	while (*s != '\0') {
92 		fn_print_char(ndo, *s);
93 		s++;
94        }
95 }
96 
97 /*
98  * Print out a null-terminated filename (or other ASCII string) from
99  * a fixed-length field in the packet buffer, or from what remains of
100  * the packet.
101  *
102  * n is the length of the fixed-length field, or the number of bytes
103  * remaining in the packet based on its on-the-network length.
104  *
105  * If ep is non-null, it should point just past the last captured byte
106  * of the packet, e.g. ndo->ndo_snapend.  If ep is NULL, we assume no
107  * truncation check, other than the checks of the field length/remaining
108  * packet data length, is needed.
109  *
110  * Return the number of bytes of string processed, including the
111  * terminating null, if not truncated; as the terminating null is
112  * included in the count, and as there must be a terminating null,
113  * this will always be non-zero.  Return 0 if truncated.
114  */
115 u_int
nd_printztn(netdissect_options * ndo,const u_char * s,u_int n,const u_char * ep)116 nd_printztn(netdissect_options *ndo,
117          const u_char *s, u_int n, const u_char *ep)
118 {
119 	u_int bytes;
120 	u_char c;
121 
122 	bytes = 0;
123 	for (;;) {
124 		if (n == 0 || (ep != NULL && s >= ep)) {
125 			/*
126 			 * Truncated.  This includes "no null before we
127 			 * got to the end of the fixed-length buffer or
128 			 * the end of the packet".
129 			 *
130 			 * XXX - BOOTP says "null-terminated", which
131 			 * means the maximum length of the string, in
132 			 * bytes, is 1 less than the size of the buffer,
133 			 * as there must always be a terminating null.
134 			 */
135 			bytes = 0;
136 			break;
137 		}
138 
139 		c = GET_U_1(s);
140 		s++;
141 		bytes++;
142 		n--;
143 		if (c == '\0') {
144 			/* End of string */
145 			break;
146 		}
147 		fn_print_char(ndo, c);
148 	}
149 	return(bytes);
150 }
151 
152 /*
153  * Print out a counted filename (or other ASCII string), part of
154  * the packet buffer.
155  * If ep is NULL, assume no truncation check is needed.
156  * Return true if truncated.
157  * Stop at ep (if given) or after n bytes, whichever is first.
158  */
159 int
nd_printn(netdissect_options * ndo,const u_char * s,u_int n,const u_char * ep)160 nd_printn(netdissect_options *ndo,
161           const u_char *s, u_int n, const u_char *ep)
162 {
163 	u_char c;
164 
165 	while (n > 0 && (ep == NULL || s < ep)) {
166 		n--;
167 		c = GET_U_1(s);
168 		s++;
169 		fn_print_char(ndo, c);
170 	}
171 	return (n == 0) ? 0 : 1;
172 }
173 
174 /*
175  * Print a null-padded filename (or other ASCII string), part of
176  * the packet buffer, filtering out non-printable characters.
177  * Stop if truncated (via GET_U_1/longjmp) or after n bytes or before
178  * the null char, whichever occurs first.
179  * The suffix comes from: j:longJmp, n:after N bytes, p:null-Padded.
180  */
181 void
nd_printjnp(netdissect_options * ndo,const u_char * s,u_int n)182 nd_printjnp(netdissect_options *ndo, const u_char *s, u_int n)
183 {
184 	u_char c;
185 
186 	while (n > 0) {
187 		c = GET_U_1(s);
188 		if (c == '\0')
189 			break;
190 		fn_print_char(ndo, c);
191 		n--;
192 		s++;
193 	}
194 }
195 
196 /*
197  * Print the timestamp .FRAC part (Microseconds/nanoseconds)
198  */
199 static void
ts_frac_print(netdissect_options * ndo,long usec)200 ts_frac_print(netdissect_options *ndo, long usec)
201 {
202 #ifdef HAVE_PCAP_SET_TSTAMP_PRECISION
203 	switch (ndo->ndo_tstamp_precision) {
204 
205 	case PCAP_TSTAMP_PRECISION_MICRO:
206 		ND_PRINT(".%06u", (unsigned)usec);
207 		break;
208 
209 	case PCAP_TSTAMP_PRECISION_NANO:
210 		ND_PRINT(".%09u", (unsigned)usec);
211 		break;
212 
213 	default:
214 		ND_PRINT(".{unknown}");
215 		break;
216 	}
217 #else
218 	ND_PRINT(".%06u", (unsigned)usec);
219 #endif
220 }
221 
222 /*
223  * Print the timestamp as [YY:MM:DD] HH:MM:SS.FRAC.
224  *   if time_flag == LOCAL_TIME print local time else UTC/GMT time
225  *   if date_flag == WITH_DATE print YY:MM:DD before HH:MM:SS.FRAC
226  */
227 static void
ts_date_hmsfrac_print(netdissect_options * ndo,long sec,long usec,enum date_flag date_flag,enum time_flag time_flag)228 ts_date_hmsfrac_print(netdissect_options *ndo, long sec, long usec,
229 		      enum date_flag date_flag, enum time_flag time_flag)
230 {
231 	time_t Time = sec;
232 	struct tm *tm;
233 	char timebuf[32];
234 	const char *timestr;
235 
236 	if ((unsigned)sec & 0x80000000) {
237 		ND_PRINT("[Error converting time]");
238 		return;
239 	}
240 
241 	if (time_flag == LOCAL_TIME)
242 		tm = localtime(&Time);
243 	else
244 		tm = gmtime(&Time);
245 
246 	if (date_flag == WITH_DATE) {
247 		timestr = nd_format_time(timebuf, sizeof(timebuf),
248 		    "%Y-%m-%d %H:%M:%S", tm);
249 	} else {
250 		timestr = nd_format_time(timebuf, sizeof(timebuf),
251 		    "%H:%M:%S", tm);
252 	}
253 	ND_PRINT("%s", timestr);
254 
255 	ts_frac_print(ndo, usec);
256 }
257 
258 /*
259  * Print the timestamp - Unix timeval style, as SECS.FRAC.
260  */
261 static void
ts_unix_print(netdissect_options * ndo,long sec,long usec)262 ts_unix_print(netdissect_options *ndo, long sec, long usec)
263 {
264 	if ((unsigned)sec & 0x80000000) {
265 		ND_PRINT("[Error converting time]");
266 		return;
267 	}
268 
269 	ND_PRINT("%u", (unsigned)sec);
270 	ts_frac_print(ndo, usec);
271 }
272 
273 /*
274  * Print the timestamp
275  */
276 void
ts_print(netdissect_options * ndo,const struct timeval * tvp)277 ts_print(netdissect_options *ndo,
278          const struct timeval *tvp)
279 {
280 	static struct timeval tv_ref;
281 	struct timeval tv_result;
282 	int negative_offset;
283 	int nano_prec;
284 
285 	switch (ndo->ndo_tflag) {
286 
287 	case 0: /* Default */
288 		ts_date_hmsfrac_print(ndo, tvp->tv_sec, tvp->tv_usec,
289 				      WITHOUT_DATE, LOCAL_TIME);
290 		ND_PRINT(" ");
291 		break;
292 
293 	case 1: /* No time stamp */
294 		break;
295 
296 	case 2: /* Unix timeval style */
297 		ts_unix_print(ndo, tvp->tv_sec, tvp->tv_usec);
298 		ND_PRINT(" ");
299 		break;
300 
301 	case 3: /* Microseconds/nanoseconds since previous packet */
302         case 5: /* Microseconds/nanoseconds since first packet */
303 #ifdef HAVE_PCAP_SET_TSTAMP_PRECISION
304 		switch (ndo->ndo_tstamp_precision) {
305 		case PCAP_TSTAMP_PRECISION_MICRO:
306 			nano_prec = 0;
307 			break;
308 		case PCAP_TSTAMP_PRECISION_NANO:
309 			nano_prec = 1;
310 			break;
311 		default:
312 			nano_prec = 0;
313 			break;
314 		}
315 #else
316 		nano_prec = 0;
317 #endif
318 		if (!(netdissect_timevalisset(&tv_ref)))
319 			tv_ref = *tvp; /* set timestamp for first packet */
320 
321 		negative_offset = netdissect_timevalcmp(tvp, &tv_ref, <);
322 		if (negative_offset)
323 			netdissect_timevalsub(&tv_ref, tvp, &tv_result, nano_prec);
324 		else
325 			netdissect_timevalsub(tvp, &tv_ref, &tv_result, nano_prec);
326 
327 		ND_PRINT((negative_offset ? "-" : " "));
328 		ts_date_hmsfrac_print(ndo, tv_result.tv_sec, tv_result.tv_usec,
329 				      WITHOUT_DATE, UTC_TIME);
330 		ND_PRINT(" ");
331 
332                 if (ndo->ndo_tflag == 3)
333 			tv_ref = *tvp; /* set timestamp for previous packet */
334 		break;
335 
336 	case 4: /* Date + Default */
337 		ts_date_hmsfrac_print(ndo, tvp->tv_sec, tvp->tv_usec,
338 				      WITH_DATE, LOCAL_TIME);
339 		ND_PRINT(" ");
340 		break;
341 	}
342 }
343 
344 /*
345  * Print an unsigned relative number of seconds (e.g. hold time, prune timer)
346  * in the form 5m1s.  This does no truncation, so 32230861 seconds
347  * is represented as 1y1w1d1h1m1s.
348  */
349 void
unsigned_relts_print(netdissect_options * ndo,uint32_t secs)350 unsigned_relts_print(netdissect_options *ndo,
351                      uint32_t secs)
352 {
353 	static const char *lengths[] = {"y", "w", "d", "h", "m", "s"};
354 	static const u_int seconds[] = {31536000, 604800, 86400, 3600, 60, 1};
355 	const char **l = lengths;
356 	const u_int *s = seconds;
357 
358 	if (secs == 0) {
359 		ND_PRINT("0s");
360 		return;
361 	}
362 	while (secs > 0) {
363 		if (secs >= *s) {
364 			ND_PRINT("%u%s", secs / *s, *l);
365 			secs -= (secs / *s) * *s;
366 		}
367 		s++;
368 		l++;
369 	}
370 }
371 
372 /*
373  * Print a signed relative number of seconds (e.g. hold time, prune timer)
374  * in the form 5m1s.  This does no truncation, so 32230861 seconds
375  * is represented as 1y1w1d1h1m1s.
376  */
377 void
signed_relts_print(netdissect_options * ndo,int32_t secs)378 signed_relts_print(netdissect_options *ndo,
379                    int32_t secs)
380 {
381 	if (secs < 0) {
382 		ND_PRINT("-");
383 		if (secs == INT32_MIN) {
384 			/*
385 			 * -2^31; you can't fit its absolute value into
386 			 * a 32-bit signed integer.
387 			 *
388 			 * Just directly pass said absolute value to
389 			 * unsigned_relts_print() directly.
390 			 *
391 			 * (XXX - does ISO C guarantee that -(-2^n),
392 			 * when calculated and cast to an n-bit unsigned
393 			 * integer type, will have the value 2^n?)
394 			 */
395 			unsigned_relts_print(ndo, 2147483648U);
396 		} else {
397 			/*
398 			 * We now know -secs will fit into an int32_t;
399 			 * negate it and pass that to unsigned_relts_print().
400 			 */
401 			unsigned_relts_print(ndo, -secs);
402 		}
403 		return;
404 	}
405 	unsigned_relts_print(ndo, secs);
406 }
407 
408 /*
409  * Format a struct tm with strftime().
410  * If the pointer to the struct tm is null, that means that the
411  * routine to convert a time_t to a struct tm failed; the localtime()
412  * and gmtime() in the Microsoft Visual Studio C library will fail,
413  * returning null, if the value is before the UNIX Epoch.
414  */
415 const char *
nd_format_time(char * buf,size_t bufsize,const char * format,const struct tm * timeptr)416 nd_format_time(char *buf, size_t bufsize, const char *format,
417          const struct tm *timeptr)
418 {
419 	if (timeptr != NULL) {
420 		if (strftime(buf, bufsize, format, timeptr) != 0)
421 			return (buf);
422 		else
423 			return ("[nd_format_time() buffer is too small]");
424 	} else
425 		return ("[localtime() or gmtime() couldn't convert the date and time]");
426 }
427 
428 /* Print the truncated string */
nd_print_trunc(netdissect_options * ndo)429 void nd_print_trunc(netdissect_options *ndo)
430 {
431 	ND_PRINT(" [|%s]", ndo->ndo_protocol);
432 }
433 
434 /* Print the protocol name */
nd_print_protocol(netdissect_options * ndo)435 void nd_print_protocol(netdissect_options *ndo)
436 {
437 	ND_PRINT("%s", ndo->ndo_protocol);
438 }
439 
440 /* Print the protocol name in caps (uppercases) */
nd_print_protocol_caps(netdissect_options * ndo)441 void nd_print_protocol_caps(netdissect_options *ndo)
442 {
443 	const char *p;
444         for (p = ndo->ndo_protocol; *p != '\0'; p++)
445                 ND_PRINT("%c", ND_ASCII_TOUPPER(*p));
446 }
447 
448 /* Print the invalid string */
nd_print_invalid(netdissect_options * ndo)449 void nd_print_invalid(netdissect_options *ndo)
450 {
451 	ND_PRINT(" (invalid)");
452 }
453 
454 /*
455  *  this is a generic routine for printing unknown data;
456  *  we pass on the linefeed plus indentation string to
457  *  get a proper output - returns 0 on error
458  */
459 
460 int
print_unknown_data(netdissect_options * ndo,const u_char * cp,const char * ident,u_int len)461 print_unknown_data(netdissect_options *ndo, const u_char *cp,
462                    const char *ident, u_int len)
463 {
464 	u_int len_to_print;
465 
466 	len_to_print = len;
467 	if (!ND_TTEST_LEN(cp, 0)) {
468 		ND_PRINT("%sDissector error: print_unknown_data called with pointer past end of packet",
469 		    ident);
470 		return(0);
471 	}
472 	if (ND_BYTES_AVAILABLE_AFTER(cp) < len_to_print)
473 		len_to_print = ND_BYTES_AVAILABLE_AFTER(cp);
474 	hex_print(ndo, ident, cp, len_to_print);
475 	return(1); /* everything is ok */
476 }
477 
478 /*
479  * Convert a token value to a string; use "fmt" if not found.
480  */
481 static const char *
tok2strbuf(const struct tok * lp,const char * fmt,u_int v,char * buf,size_t bufsize)482 tok2strbuf(const struct tok *lp, const char *fmt,
483 	   u_int v, char *buf, size_t bufsize)
484 {
485 	if (lp != NULL) {
486 		while (lp->s != NULL) {
487 			if (lp->v == v)
488 				return (lp->s);
489 			++lp;
490 		}
491 	}
492 	if (fmt == NULL)
493 		fmt = "#%d";
494 
495 	(void)snprintf(buf, bufsize, fmt, v);
496 	return (const char *)buf;
497 }
498 
499 /*
500  * Convert a token value to a string; use "fmt" if not found.
501  * Uses tok2strbuf() on one of four local static buffers of size TOKBUFSIZE
502  * in round-robin fashion.
503  */
504 const char *
tok2str(const struct tok * lp,const char * fmt,u_int v)505 tok2str(const struct tok *lp, const char *fmt,
506 	u_int v)
507 {
508 	static char buf[4][TOKBUFSIZE];
509 	static int idx = 0;
510 	char *ret;
511 
512 	ret = buf[idx];
513 	idx = (idx+1) & 3;
514 	return tok2strbuf(lp, fmt, v, ret, sizeof(buf[0]));
515 }
516 
517 /*
518  * Convert a bit token value to a string; use "fmt" if not found.
519  * this is useful for parsing bitfields, the output strings are separated
520  * if the s field is positive.
521  *
522  * A token matches iff it has one or more bits set and every bit that is set
523  * in the token is set in v. Consequently, a 0 token never matches.
524  */
525 static char *
bittok2str_internal(const struct tok * lp,const char * fmt,u_int v,const char * sep)526 bittok2str_internal(const struct tok *lp, const char *fmt,
527 	   u_int v, const char *sep)
528 {
529         static char buf[1024+1]; /* our string buffer */
530         char *bufp = buf;
531         size_t space_left = sizeof(buf), string_size;
532         const char * sepstr = "";
533 
534         while (lp != NULL && lp->s != NULL) {
535             if (lp->v && (v & lp->v) == lp->v) {
536                 /* ok we have found something */
537                 if (space_left <= 1)
538                     return (buf); /* only enough room left for NUL, if that */
539                 string_size = strlcpy(bufp, sepstr, space_left);
540                 if (string_size >= space_left)
541                     return (buf);    /* we ran out of room */
542                 bufp += string_size;
543                 space_left -= string_size;
544                 if (space_left <= 1)
545                     return (buf); /* only enough room left for NUL, if that */
546                 string_size = strlcpy(bufp, lp->s, space_left);
547                 if (string_size >= space_left)
548                     return (buf);    /* we ran out of room */
549                 bufp += string_size;
550                 space_left -= string_size;
551                 sepstr = sep;
552             }
553             lp++;
554         }
555 
556         if (bufp == buf)
557             /* bummer - lets print the "unknown" message as advised in the fmt string if we got one */
558             (void)snprintf(buf, sizeof(buf), fmt == NULL ? "#%08x" : fmt, v);
559         return (buf);
560 }
561 
562 /*
563  * Convert a bit token value to a string; use "fmt" if not found.
564  * this is useful for parsing bitfields, the output strings are not separated.
565  */
566 char *
bittok2str_nosep(const struct tok * lp,const char * fmt,u_int v)567 bittok2str_nosep(const struct tok *lp, const char *fmt,
568 	   u_int v)
569 {
570     return (bittok2str_internal(lp, fmt, v, ""));
571 }
572 
573 /*
574  * Convert a bit token value to a string; use "fmt" if not found.
575  * this is useful for parsing bitfields, the output strings are comma separated.
576  */
577 char *
bittok2str(const struct tok * lp,const char * fmt,u_int v)578 bittok2str(const struct tok *lp, const char *fmt,
579 	   u_int v)
580 {
581     return (bittok2str_internal(lp, fmt, v, ", "));
582 }
583 
584 /*
585  * Convert a value to a string using an array; the macro
586  * tok2strary() in <netdissect.h> is the public interface to
587  * this function and ensures that the second argument is
588  * correct for bounds-checking.
589  */
590 const char *
tok2strary_internal(const char ** lp,int n,const char * fmt,int v)591 tok2strary_internal(const char **lp, int n, const char *fmt,
592 	int v)
593 {
594 	static char buf[TOKBUFSIZE];
595 
596 	if (v >= 0 && v < n && lp[v] != NULL)
597 		return lp[v];
598 	if (fmt == NULL)
599 		fmt = "#%d";
600 	(void)snprintf(buf, sizeof(buf), fmt, v);
601 	return (buf);
602 }
603 
604 const struct tok *
uint2tokary_internal(const struct uint_tokary dict[],const size_t size,const u_int val)605 uint2tokary_internal(const struct uint_tokary dict[], const size_t size,
606                      const u_int val)
607 {
608 	size_t i;
609 	/* Try a direct lookup before the full scan. */
610 	if (val < size && dict[val].uintval == val)
611 		return dict[val].tokary; /* OK if NULL */
612 	for (i = 0; i < size; i++)
613 		if (dict[i].uintval == val)
614 			return dict[i].tokary; /* OK if NULL */
615 	return NULL;
616 }
617 
618 /*
619  * Convert a 32-bit netmask to prefixlen if possible
620  * the function returns the prefix-len; if plen == -1
621  * then conversion was not possible;
622  */
623 
624 int
mask2plen(uint32_t mask)625 mask2plen(uint32_t mask)
626 {
627 	const uint32_t bitmasks[33] = {
628 		0x00000000,
629 		0x80000000, 0xc0000000, 0xe0000000, 0xf0000000,
630 		0xf8000000, 0xfc000000, 0xfe000000, 0xff000000,
631 		0xff800000, 0xffc00000, 0xffe00000, 0xfff00000,
632 		0xfff80000, 0xfffc0000, 0xfffe0000, 0xffff0000,
633 		0xffff8000, 0xffffc000, 0xffffe000, 0xfffff000,
634 		0xfffff800, 0xfffffc00, 0xfffffe00, 0xffffff00,
635 		0xffffff80, 0xffffffc0, 0xffffffe0, 0xfffffff0,
636 		0xfffffff8, 0xfffffffc, 0xfffffffe, 0xffffffff
637 	};
638 	int prefix_len = 32;
639 
640 	/* let's see if we can transform the mask into a prefixlen */
641 	while (prefix_len >= 0) {
642 		if (bitmasks[prefix_len] == mask)
643 			break;
644 		prefix_len--;
645 	}
646 	return (prefix_len);
647 }
648 
649 int
mask62plen(const u_char * mask)650 mask62plen(const u_char *mask)
651 {
652 	u_char bitmasks[9] = {
653 		0x00,
654 		0x80, 0xc0, 0xe0, 0xf0,
655 		0xf8, 0xfc, 0xfe, 0xff
656 	};
657 	int byte;
658 	int cidr_len = 0;
659 
660 	for (byte = 0; byte < 16; byte++) {
661 		u_int bits;
662 
663 		for (bits = 0; bits < (sizeof (bitmasks) / sizeof (bitmasks[0])); bits++) {
664 			if (mask[byte] == bitmasks[bits]) {
665 				cidr_len += bits;
666 				break;
667 			}
668 		}
669 
670 		if (mask[byte] != 0xff)
671 			break;
672 	}
673 	return (cidr_len);
674 }
675 
676 /*
677  * Routine to print out information for text-based protocols such as FTP,
678  * HTTP, SMTP, RTSP, SIP, ....
679  */
680 #define MAX_TOKEN	128
681 
682 /*
683  * Fetch a token from a packet, starting at the specified index,
684  * and return the length of the token.
685  *
686  * Returns 0 on error; yes, this is indistinguishable from an empty
687  * token, but an "empty token" isn't a valid token - it just means
688  * either a space character at the beginning of the line (this
689  * includes a blank line) or no more tokens remaining on the line.
690  */
691 static int
fetch_token(netdissect_options * ndo,const u_char * pptr,u_int idx,u_int len,u_char * tbuf,size_t tbuflen)692 fetch_token(netdissect_options *ndo, const u_char *pptr, u_int idx, u_int len,
693     u_char *tbuf, size_t tbuflen)
694 {
695 	size_t toklen = 0;
696 	u_char c;
697 
698 	for (; idx < len; idx++) {
699 		if (!ND_TTEST_1(pptr + idx)) {
700 			/* ran past end of captured data */
701 			return (0);
702 		}
703 		c = GET_U_1(pptr + idx);
704 		if (!ND_ISASCII(c)) {
705 			/* not an ASCII character */
706 			return (0);
707 		}
708 		if (c == ' ' || c == '\t' || c == '\r' || c == '\n') {
709 			/* end of token */
710 			break;
711 		}
712 		if (!ND_ASCII_ISPRINT(c)) {
713 			/* not part of a command token or response code */
714 			return (0);
715 		}
716 		if (toklen + 2 > tbuflen) {
717 			/* no room for this character and terminating '\0' */
718 			return (0);
719 		}
720 		tbuf[toklen] = c;
721 		toklen++;
722 	}
723 	if (toklen == 0) {
724 		/* no token */
725 		return (0);
726 	}
727 	tbuf[toklen] = '\0';
728 
729 	/*
730 	 * Skip past any white space after the token, until we see
731 	 * an end-of-line (CR or LF).
732 	 */
733 	for (; idx < len; idx++) {
734 		if (!ND_TTEST_1(pptr + idx)) {
735 			/* ran past end of captured data */
736 			break;
737 		}
738 		c = GET_U_1(pptr + idx);
739 		if (c == '\r' || c == '\n') {
740 			/* end of line */
741 			break;
742 		}
743 		if (!ND_ASCII_ISPRINT(c)) {
744 			/* not a printable ASCII character */
745 			break;
746 		}
747 		if (c != ' ' && c != '\t' && c != '\r' && c != '\n') {
748 			/* beginning of next token */
749 			break;
750 		}
751 	}
752 	return (idx);
753 }
754 
755 /*
756  * Scan a buffer looking for a line ending - LF or CR-LF.
757  * Return the index of the character after the line ending or 0 if
758  * we encounter a non-ASCII or non-printable character or don't find
759  * the line ending.
760  */
761 static u_int
print_txt_line(netdissect_options * ndo,const char * prefix,const u_char * pptr,u_int idx,u_int len)762 print_txt_line(netdissect_options *ndo, const char *prefix,
763 	       const u_char *pptr, u_int idx, u_int len)
764 {
765 	u_int startidx;
766 	u_int linelen;
767 	u_char c;
768 
769 	startidx = idx;
770 	while (idx < len) {
771 		c = GET_U_1(pptr + idx);
772 		if (c == '\n') {
773 			/*
774 			 * LF without CR; end of line.
775 			 * Skip the LF and print the line, with the
776 			 * exception of the LF.
777 			 */
778 			linelen = idx - startidx;
779 			idx++;
780 			goto print;
781 		} else if (c == '\r') {
782 			/* CR - any LF? */
783 			if ((idx+1) >= len) {
784 				/* not in this packet */
785 				return (0);
786 			}
787 			if (GET_U_1(pptr + idx + 1) == '\n') {
788 				/*
789 				 * CR-LF; end of line.
790 				 * Skip the CR-LF and print the line, with
791 				 * the exception of the CR-LF.
792 				 */
793 				linelen = idx - startidx;
794 				idx += 2;
795 				goto print;
796 			}
797 
798 			/*
799 			 * CR followed by something else; treat this
800 			 * as if it were binary data, and don't print
801 			 * it.
802 			 */
803 			return (0);
804 		} else if (!ND_ASCII_ISPRINT(c) && c != '\t') {
805 			/*
806 			 * Not a printable ASCII character and not a tab;
807 			 * treat this as if it were binary data, and
808 			 * don't print it.
809 			 */
810 			return (0);
811 		}
812 		idx++;
813 	}
814 
815 	/*
816 	 * All printable ASCII, but no line ending after that point
817 	 * in the buffer; treat this as if it were truncated.
818 	 */
819 	linelen = idx - startidx;
820 	ND_PRINT("%s%.*s", prefix, (int)linelen, pptr + startidx);
821 	nd_print_trunc(ndo);
822 	return (0);
823 
824 print:
825 	ND_PRINT("%s%.*s", prefix, (int)linelen, pptr + startidx);
826 	return (idx);
827 }
828 
829 /* Assign needed before calling txtproto_print(): ndo->ndo_protocol = "proto" */
830 void
txtproto_print(netdissect_options * ndo,const u_char * pptr,u_int len,const char ** cmds,u_int flags)831 txtproto_print(netdissect_options *ndo, const u_char *pptr, u_int len,
832 	       const char **cmds, u_int flags)
833 {
834 	u_int idx, eol;
835 	u_char token[MAX_TOKEN+1];
836 	const char *cmd;
837 	int print_this = 0;
838 
839 	if (cmds != NULL) {
840 		/*
841 		 * This protocol has more than just request and
842 		 * response lines; see whether this looks like a
843 		 * request or response and, if so, print it and,
844 		 * in verbose mode, print everything after it.
845 		 *
846 		 * This is for HTTP-like protocols, where we
847 		 * want to print requests and responses, but
848 		 * don't want to print continuations of request
849 		 * or response bodies in packets that don't
850 		 * contain the request or response line.
851 		 */
852 		idx = fetch_token(ndo, pptr, 0, len, token, sizeof(token));
853 		if (idx != 0) {
854 			/* Is this a valid request name? */
855 			while ((cmd = *cmds++) != NULL) {
856 				if (ascii_strcasecmp((const char *)token, cmd) == 0) {
857 					/* Yes. */
858 					print_this = 1;
859 					break;
860 				}
861 			}
862 
863 			/*
864 			 * No - is this a valid response code (3 digits)?
865 			 *
866 			 * Is this token the response code, or is the next
867 			 * token the response code?
868 			 */
869 			if (flags & RESP_CODE_SECOND_TOKEN) {
870 				/*
871 				 * Next token - get it.
872 				 */
873 				idx = fetch_token(ndo, pptr, idx, len, token,
874 				    sizeof(token));
875 			}
876 			if (idx != 0) {
877 				if (ND_ASCII_ISDIGIT(token[0]) && ND_ASCII_ISDIGIT(token[1]) &&
878 				    ND_ASCII_ISDIGIT(token[2]) && token[3] == '\0') {
879 					/* Yes. */
880 					print_this = 1;
881 				}
882 			}
883 		}
884 	} else {
885 		/*
886 		 * Either:
887 		 *
888 		 * 1) This protocol has only request and response lines
889 		 *    (e.g., FTP, where all the data goes over a different
890 		 *    connection); assume the payload is a request or
891 		 *    response.
892 		 *
893 		 * or
894 		 *
895 		 * 2) This protocol is just text, so that we should
896 		 *    always, at minimum, print the first line and,
897 		 *    in verbose mode, print all lines.
898 		 */
899 		print_this = 1;
900 	}
901 
902 	nd_print_protocol_caps(ndo);
903 
904 	if (print_this) {
905 		/*
906 		 * In non-verbose mode, just print the protocol, followed
907 		 * by the first line.
908 		 *
909 		 * In verbose mode, print lines as text until we run out
910 		 * of characters or see something that's not a
911 		 * printable-ASCII line.
912 		 */
913 		if (ndo->ndo_vflag) {
914 			/*
915 			 * We're going to print all the text lines in the
916 			 * request or response; just print the length
917 			 * on the first line of the output.
918 			 */
919 			ND_PRINT(", length: %u", len);
920 			for (idx = 0;
921 			    idx < len && (eol = print_txt_line(ndo, "\n\t", pptr, idx, len)) != 0;
922 			    idx = eol)
923 				;
924 		} else {
925 			/*
926 			 * Just print the first text line.
927 			 */
928 			print_txt_line(ndo, ": ", pptr, 0, len);
929 		}
930 	}
931 }
932 
933 #if (defined(__i386__) || defined(_M_IX86) || defined(__X86__) || defined(__x86_64__) || defined(_M_X64)) || \
934     (defined(__arm__) || defined(_M_ARM) || defined(__aarch64__)) || \
935     (defined(__m68k__) && (!defined(__mc68000__) && !defined(__mc68010__))) || \
936     (defined(__ppc__) || defined(__ppc64__) || defined(_M_PPC) || defined(_ARCH_PPC) || defined(_ARCH_PPC64)) || \
937     (defined(__s390__) || defined(__s390x__) || defined(__zarch__)) || \
938     defined(__vax__)
939 /*
940  * The processor natively handles unaligned loads, so just use memcpy()
941  * and memcmp(), to enable those optimizations.
942  *
943  * XXX - are those all the x86 tests we need?
944  * XXX - do we need to worry about ARMv1 through ARMv5, which didn't
945  * support unaligned loads, and, if so, do we need to worry about all
946  * of them, or just some of them, e.g. ARMv5?
947  * XXX - are those the only 68k tests we need not to generated
948  * unaligned accesses if the target is the 68000 or 68010?
949  * XXX - are there any tests we don't need, because some definitions are for
950  * compilers that also predefine the GCC symbols?
951  * XXX - do we need to test for both 32-bit and 64-bit versions of those
952  * architectures in all cases?
953  */
954 #else
955 /*
956  * The processor doesn't natively handle unaligned loads,
957  * and the compiler might "helpfully" optimize memcpy()
958  * and memcmp(), when handed pointers that would normally
959  * be properly aligned, into sequences that assume proper
960  * alignment.
961  *
962  * Do copies and compares of possibly-unaligned data by
963  * calling routines that wrap memcpy() and memcmp(), to
964  * prevent that optimization.
965  */
966 void
unaligned_memcpy(void * p,const void * q,size_t l)967 unaligned_memcpy(void *p, const void *q, size_t l)
968 {
969 	memcpy(p, q, l);
970 }
971 
972 /* As with memcpy(), so with memcmp(). */
973 int
unaligned_memcmp(const void * p,const void * q,size_t l)974 unaligned_memcmp(const void *p, const void *q, size_t l)
975 {
976 	return (memcmp(p, q, l));
977 }
978 #endif
979 
980