The Tcpdump Group git mirrors - tcpdump/blob - util.c

   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 #ifndef lint
  23 static const char rcsid[] =
  24     "@(#) $Header: /tcpdump/master/tcpdump/util.c,v 1.81 2002-11-07 20:07:58 hannes Exp $ (LBL)";
  25 #endif
  26
  27 #ifdef HAVE_CONFIG_H
  28 #include "config.h"
  29 #endif
  30
  31 #include <tcpdump-stdinc.h>
  32
  33 #include <sys/stat.h>
  34
  35 #include <errno.h>
  36 #ifdef HAVE_FCNTL_H
  37 #include <fcntl.h>
  38 #endif
  39 #include <pcap.h>
  40 #include <stdio.h>
  41 #include <stdarg.h>
  42 #include <stdlib.h>
  43 #include <string.h>
  44
  45 #include "interface.h"
  46
  47 /*
  48  * Print out a filename (or other ascii string).
  49  * If ep is NULL, assume no truncation check is needed.
  50  * Return true if truncated.
  51  */
  52 int
  53 fn_print(register const u_char *s, register const u_char *ep)
  54 {
  55         register int ret;
  56         register u_char c;
  57
  58         ret = 1;                        /* assume truncated */
  59         while (ep == NULL || s < ep) {
  60                 c = *s++;
  61                 if (c == '\0') {
  62                         ret = 0;
  63                         break;
  64                 }
  65                 if (!isascii(c)) {
  66                         c = toascii(c);
  67                         putchar('M');
  68                         putchar('-');
  69                 }
  70                 if (!isprint(c)) {
  71                         c ^= 0x40;      /* DEL to ?, others to alpha */
  72                         putchar('^');
  73                 }
  74                 putchar(c);
  75         }
  76         return(ret);
  77 }
  78
  79 /*
  80  * Print out a counted filename (or other ascii string).
  81  * If ep is NULL, assume no truncation check is needed.
  82  * Return true if truncated.
  83  */
  84 int
  85 fn_printn(register const u_char *s, register u_int n,
  86           register const u_char *ep)
  87 {
  88         register int ret;
  89         register 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(register const struct timeval *tvp)
 117 {
 118         register int s;
 119         struct tm *tm;
 120         time_t Time;
 121         static unsigned b_sec;
 122         static unsigned b_usec;
 123
 124         switch(tflag) {
 125         case 1: /* Default */
 126                 s = (tvp->tv_sec + thiszone) % 86400;
 127                 (void)printf("%02d:%02d:%02d.%06u ",
 128                              s / 3600, (s % 3600) / 60, s % 60,
 129                              (unsigned)tvp->tv_usec);
 130                 break;
 131         case -1: /* Unix timeval style */
 132                 (void)printf("%u.%06u ",
 133                              (unsigned)tvp->tv_sec,
 134                              (unsigned)tvp->tv_usec);
 135                 break;
 136         case -2:
 137                 if (b_sec == 0) {
 138                         printf("000000 ");
 139                 } else {
 140                         int d_usec = tvp->tv_usec - b_usec;
 141                         int d_sec = tvp->tv_sec - b_sec;
 142
 143                         while (d_usec < 0) {
 144                                 d_usec += 1000000;
 145                                 d_sec--;
 146                         }
 147                         if (d_sec)
 148                                 printf("%d. ", d_sec);
 149                         printf("%06d ", d_usec);
 150                 }
 151                 b_sec = tvp->tv_sec;
 152                 b_usec = tvp->tv_usec;
 153                 break;
 154         case -3: /* Default + Date*/
 155                 s = (tvp->tv_sec + thiszone) % 86400;
 156                 Time = (tvp->tv_sec + thiszone) - s;
 157                 tm  = gmtime (&Time);
 158                 (void)printf("%02d/%02d/%04d %02d:%02d:%02d.%06u ",
 159                              tm->tm_mon+1, tm->tm_mday,
 160                              tm->tm_year+1900,
 161                              s / 3600, (s % 3600) / 60,
 162                              s % 60, (unsigned)tvp->tv_usec);
 163                 break;
 164         }
 165 }
 166
 167 /*
 168  * Print a relative number of seconds (e.g. hold time, prune timer)
 169  * in the form 5m1s.  This does no truncation, so 32230861 seconds
 170  * is represented as 1y1w1d1h1m1s.
 171  */
 172 void
 173 relts_print(int secs)
 174 {
 175         static const char *lengths[] = {"y", "w", "d", "h", "m", "s"};
 176         static const int seconds[] = {31536000, 604800, 86400, 3600, 60, 1};
 177         const char **l = lengths;
 178         const int *s = seconds;
 179
 180         if (secs == 0) {
 181                 (void)printf("0s");
 182                 return;
 183         }
 184         if (secs < 0) {
 185                 (void)printf("-");
 186                 secs = -secs;
 187         }
 188         while (secs > 0) {
 189                 if (secs >= *s) {
 190                         (void)printf("%d%s", secs / *s, *l);
 191                         secs -= (secs / *s) * *s;
 192                 }
 193                 s++;
 194                 l++;
 195         }
 196 }
 197
 198 /*
 199  *  this is a generic routine for printing unknown data;
 200  *  we pass on the linefeed plus indentation string to
 201  *  get a proper output - returns 0 on error
 202  */
 203
 204 int
 205 print_unknown_data(const u_char *cp,const char *lf,int len)
 206 {
 207         int i;
 208
 209         if (len ==0)
 210             return(0);
 211
 212         printf("%s0x0000: ",lf);
 213         for(i=0;i<len;i++) {
 214             if (!TTEST2(*(cp+i), 1)) {
 215               printf("%spacket exceeded snapshot",lf);
 216               return(0);
 217             }
 218             printf("%02x",*(cp+i));
 219             if (i%2)
 220                 printf(" ");
 221             if (i/16!=(i+1)/16) {
 222                 if (i<(len-1))
 223                     printf("%s0x%04x: ",lf,i);
 224             }
 225         }
 226         return(1); /* everything is ok */
 227 }
 228
 229 /*
 230  * Convert a token value to a string; use "fmt" if not found.
 231  */
 232 const char *
 233 tok2str(register const struct tok *lp, register const char *fmt,
 234         register int v)
 235 {
 236         static char buf[128];
 237
 238         while (lp->s != NULL) {
 239                 if (lp->v == v)
 240                         return (lp->s);
 241                 ++lp;
 242         }
 243         if (fmt == NULL)
 244                 fmt = "#%d";
 245         (void)snprintf(buf, sizeof(buf), fmt, v);
 246         return (buf);
 247 }
 248
 249 /*
 250  * Convert a bit token value to a string; use "fmt" if not found.
 251  * this is useful for parsing bitfields, the output strings are comma seperated
 252  */
 253 char *
 254 bittok2str(register const struct tok *lp, register const char *fmt,
 255         register int v)
 256 {
 257         static char buf[256]; /* our stringbuffer */
 258         int buflen=0;
 259         register int rotbit; /* this is the bit we rotate through all bitpositions */
 260         register int tokval;
 261
 262         while (lp->s != NULL) {
 263             tokval=lp->v;   /* load our first value */
 264             rotbit=1;
 265             while (rotbit != 0) {
 266                 /*
 267                  * lets AND the rotating bit with our token value
 268                  * and see if we have got a match
 269                  */
 270                 if (tokval == (v&rotbit)) {
 271                     /* ok we have found something */
 272                     buflen+=snprintf(buf+buflen, sizeof(buf)-buflen, "%s, ",lp->s);
 273                     break;
 274                 }
 275                 rotbit=rotbit<<1; /* no match - lets shift and try again */
 276             }
 277             lp++;
 278         }
 279
 280         if (buflen != 0) { /* did we find anything */
 281             /* yep, set the the trailing zero 2 bytes before to eliminate the last comma & whitespace */
 282             buf[buflen-2] = '\0';
 283             return (buf);
 284         }
 285         else {
 286             /* bummer - lets print the "unknown" message as advised in the fmt string if we got one */
 287             if (fmt == NULL)
 288                 fmt = "#%d";
 289             (void)snprintf(buf, sizeof(buf), fmt, v);
 290             return (buf);
 291         }
 292 }
 293
 294 /*
 295  * Convert a value to a string using an array; the macro
 296  * tok2strary() in <interface.h> is the public interface to
 297  * this function and ensures that the second argument is
 298  * correct for bounds-checking.
 299  */
 300 const char *
 301 tok2strary_internal(register const char **lp, int n, register const char *fmt,
 302         register int v)
 303 {
 304         static char buf[128];
 305
 306         if (v >= 0 && v < n && lp[v] != NULL)
 307                 return lp[v];
 308         if (fmt == NULL)
 309                 fmt = "#%d";
 310         (void)snprintf(buf, sizeof(buf), fmt, v);
 311         return (buf);
 312 }
 313
 314 /* VARARGS */
 315 void
 316 error(const char *fmt, ...)
 317 {
 318         va_list ap;
 319
 320         (void)fprintf(stderr, "%s: ", program_name);
 321         va_start(ap, fmt);
 322         (void)vfprintf(stderr, fmt, ap);
 323         va_end(ap);
 324         if (*fmt) {
 325                 fmt += strlen(fmt);
 326                 if (fmt[-1] != '\n')
 327                         (void)fputc('\n', stderr);
 328         }
 329         exit(1);
 330         /* NOTREACHED */
 331 }
 332
 333 /* VARARGS */
 334 void
 335 warning(const char *fmt, ...)
 336 {
 337         va_list ap;
 338
 339         (void)fprintf(stderr, "%s: WARNING: ", program_name);
 340         va_start(ap, fmt);
 341         (void)vfprintf(stderr, fmt, ap);
 342         va_end(ap);
 343         if (*fmt) {
 344                 fmt += strlen(fmt);
 345                 if (fmt[-1] != '\n')
 346                         (void)fputc('\n', stderr);
 347         }
 348 }
 349
 350 /*
 351  * Copy arg vector into a new buffer, concatenating arguments with spaces.
 352  */
 353 char *
 354 copy_argv(register char **argv)
 355 {
 356         register char **p;
 357         register u_int len = 0;
 358         char *buf;
 359         char *src, *dst;
 360
 361         p = argv;
 362         if (*p == 0)
 363                 return 0;
 364
 365         while (*p)
 366                 len += strlen(*p++) + 1;
 367
 368         buf = (char *)malloc(len);
 369         if (buf == NULL)
 370                 error("copy_argv: malloc");
 371
 372         p = argv;
 373         dst = buf;
 374         while ((src = *p++) != NULL) {
 375                 while ((*dst++ = *src++) != '\0')
 376                         ;
 377                 dst[-1] = ' ';
 378         }
 379         dst[-1] = '\0';
 380
 381         return buf;
 382 }
 383
 384 char *
 385 read_infile(char *fname)
 386 {
 387         register int fd, cc;
 388         register char *cp;
 389         struct stat buf;
 390
 391         fd = open(fname, O_RDONLY);
 392         if (fd < 0)
 393                 error("can't open %s: %s", fname, pcap_strerror(errno));
 394
 395         if (fstat(fd, &buf) < 0)
 396                 error("can't stat %s: %s", fname, pcap_strerror(errno));
 397
 398         cp = malloc((u_int)buf.st_size + 1);
 399         if (cp == NULL)
 400                 error("malloc(%d) for %s: %s", (u_int)buf.st_size + 1,
 401                         fname, pcap_strerror(errno));
 402         cc = read(fd, cp, (u_int)buf.st_size);
 403         if (cc < 0)
 404                 error("read %s: %s", fname, pcap_strerror(errno));
 405         if (cc != buf.st_size)
 406 #ifndef WIN32
 407                 error("short read %s (%d != %d)", fname, cc, (int)buf.st_size);
 408 #else
 409 /* Windows seems not to like the final \xa character */
 410         {
 411                 char *pdest;
 412                 pdest=strchr( cp, '\xa');
 413                 *pdest=0;
 414         }
 415 #endif /* WIN32 */
 416         cp[(int)buf.st_size] = '\0';
 417
 418         return (cp);
 419 }
 420
 421 void
 422 safeputs(const char *s)
 423 {
 424         while (*s) {
 425                 safeputchar(*s);
 426                 s++;
 427         }
 428 }
 429
 430 void
 431 safeputchar(int c)
 432 {
 433         unsigned char ch;
 434
 435         ch = (unsigned char)(c & 0xff);
 436         if (ch < 0x80 && isprint(ch))
 437                 printf("%c", ch);
 438         else
 439                 printf("\\%03o", ch);
 440 }