The Tcpdump Group git mirrors - libpcap/blob - testprogs/filtertest.c

   1 /*
   2  * Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 2000
   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 #include "varattrs.h"
  23
  24 #ifndef lint
  25 static const char copyright[] _U_ =
  26     "@(#) Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 2000\n\
  27 The Regents of the University of California.  All rights reserved.\n";
  28 #endif
  29
  30 #ifdef HAVE_CONFIG_H
  31 #include <config.h>
  32 #endif
  33
  34 #include <pcap.h>
  35 #include <stdio.h>
  36 #include <stdlib.h>
  37 #include <string.h>
  38 #include <stdarg.h>
  39 #include <limits.h>
  40 #ifdef _WIN32
  41   #include "getopt.h"
  42   #include "unix.h"
  43 #else
  44   #include <unistd.h>
  45 #endif
  46 #include <fcntl.h>
  47 #include <errno.h>
  48 #ifdef _WIN32
  49   #include <winsock2.h>
  50   #include <ws2tcpip.h>
  51 #else
  52   #include <sys/socket.h>
  53   #include <arpa/inet.h>
  54 #endif
  55 #include <sys/types.h>
  56 #include <sys/stat.h>
  57
  58 #include "pcap/funcattrs.h"
  59
  60 #define MAXIMUM_SNAPLEN         262144
  61
  62 #ifdef BDEBUG
  63 /*
  64  * We have pcap_set_optimizer_debug() and pcap_set_print_dot_graph() in
  65  * libpcap; declare them (they're not declared by any libpcap header,
  66  * because they're special hacks, only available if libpcap was configured
  67  * to include them, and only intended for use by libpcap developers trying
  68  * to debug the optimizer for filter expressions).
  69  */
  70 PCAP_API void pcap_set_optimizer_debug(int);
  71 PCAP_API void pcap_set_print_dot_graph(int);
  72 #endif
  73
  74 static char *program_name;
  75
  76 /* Forwards */
  77 static void PCAP_NORETURN usage(void);
  78 static void PCAP_NORETURN error(const char *, ...) PCAP_PRINTFLIKE(1, 2);
  79 static void warn(const char *, ...) PCAP_PRINTFLIKE(1, 2);
  80
  81 /*
  82  * On Windows, we need to open the file in binary mode, so that
  83  * we get all the bytes specified by the size we get from "fstat()".
  84  * On UNIX, that's not necessary.  O_BINARY is defined on Windows;
  85  * we define it as 0 if it's not defined, so it does nothing.
  86  */
  87 #ifndef O_BINARY
  88 #define O_BINARY        0
  89 #endif
  90
  91 static char *
  92 read_infile(char *fname)
  93 {
  94         register int i, fd, cc;
  95         register char *cp;
  96         struct stat buf;
  97
  98         fd = open(fname, O_RDONLY|O_BINARY);
  99         if (fd < 0)
 100                 error("can't open %s: %s", fname, pcap_strerror(errno));
 101
 102         if (fstat(fd, &buf) < 0)
 103                 error("can't stat %s: %s", fname, pcap_strerror(errno));
 104
 105         /*
 106          * _read(), on Windows, has an unsigned int byte count and an
 107          * int return value, so we can't handle a file bigger than
 108          * INT_MAX - 1 bytes (and have no reason to do so; a filter *that*
 109          * big will take forever to compile).  (The -1 is for the '\0' at
 110          * the end of the string.)
 111          */
 112         if (buf.st_size > INT_MAX - 1)
 113                 error("%s is larger than %d bytes; that's too large", fname,
 114                     INT_MAX - 1);
 115         cp = malloc((u_int)buf.st_size + 1);
 116         if (cp == NULL)
 117                 error("malloc(%d) for %s: %s", (u_int)buf.st_size + 1,
 118                         fname, pcap_strerror(errno));
 119         cc = (int)read(fd, cp, (u_int)buf.st_size);
 120         if (cc < 0)
 121                 error("read %s: %s", fname, pcap_strerror(errno));
 122         if (cc != buf.st_size)
 123                 error("short read %s (%d != %d)", fname, cc, (int)buf.st_size);
 124
 125         close(fd);
 126         /* replace "# comment" with spaces */
 127         for (i = 0; i < cc; i++) {
 128                 if (cp[i] == '#')
 129                         while (i < cc && cp[i] != '\n')
 130                                 cp[i++] = ' ';
 131         }
 132         cp[cc] = '\0';
 133         return (cp);
 134 }
 135
 136 /* VARARGS */
 137 static void
 138 error(const char *fmt, ...)
 139 {
 140         va_list ap;
 141
 142         (void)fprintf(stderr, "%s: ", program_name);
 143         va_start(ap, fmt);
 144         (void)vfprintf(stderr, fmt, ap);
 145         va_end(ap);
 146         if (*fmt) {
 147                 fmt += strlen(fmt);
 148                 if (fmt[-1] != '\n')
 149                         (void)fputc('\n', stderr);
 150         }
 151         exit(1);
 152         /* NOTREACHED */
 153 }
 154
 155 /* VARARGS */
 156 static void
 157 warn(const char *fmt, ...)
 158 {
 159         va_list ap;
 160
 161         (void)fprintf(stderr, "%s: WARNING: ", program_name);
 162         va_start(ap, fmt);
 163         (void)vfprintf(stderr, fmt, ap);
 164         va_end(ap);
 165         if (*fmt) {
 166                 fmt += strlen(fmt);
 167                 if (fmt[-1] != '\n')
 168                         (void)fputc('\n', stderr);
 169         }
 170 }
 171
 172 /*
 173  * Copy arg vector into a new buffer, concatenating arguments with spaces.
 174  */
 175 static char *
 176 copy_argv(register char **argv)
 177 {
 178         register char **p;
 179         register u_int len = 0;
 180         char *buf;
 181         char *src, *dst;
 182
 183         p = argv;
 184         if (*p == 0)
 185                 return 0;
 186
 187         while (*p)
 188                 len += strlen(*p++) + 1;
 189
 190         buf = (char *)malloc(len);
 191         if (buf == NULL)
 192                 error("copy_argv: malloc");
 193
 194         p = argv;
 195         dst = buf;
 196         while ((src = *p++) != NULL) {
 197                 while ((*dst++ = *src++) != '\0')
 198                         ;
 199                 dst[-1] = ' ';
 200         }
 201         dst[-1] = '\0';
 202
 203         return buf;
 204 }
 205
 206 int
 207 main(int argc, char **argv)
 208 {
 209         char *cp;
 210         int op;
 211         int dflag;
 212         int gflag;
 213         char *infile;
 214         int Oflag;
 215         int snaplen;
 216         char *p;
 217         int dlt;
 218         int have_fcode = 0;
 219         bpf_u_int32 netmask = PCAP_NETMASK_UNKNOWN;
 220         char *cmdbuf;
 221         pcap_t *pd;
 222         struct bpf_program fcode;
 223
 224 #ifdef _WIN32
 225         if (pcap_wsockinit() != 0)
 226                 return 1;
 227 #endif /* _WIN32 */
 228
 229         dflag = 1;
 230         gflag = 0;
 231
 232         infile = NULL;
 233         Oflag = 1;
 234         snaplen = MAXIMUM_SNAPLEN;
 235
 236         if ((cp = strrchr(argv[0], '/')) != NULL)
 237                 program_name = cp + 1;
 238         else
 239                 program_name = argv[0];
 240
 241         opterr = 0;
 242         while ((op = getopt(argc, argv, "dF:gm:Os:")) != -1) {
 243                 switch (op) {
 244
 245                 case 'd':
 246                         ++dflag;
 247                         break;
 248
 249                 case 'g':
 250 #ifdef BDEBUG
 251                         ++gflag;
 252 #else
 253                         error("libpcap and filtertest not built with optimizer debugging enabled");
 254 #endif
 255                         break;
 256
 257                 case 'F':
 258                         infile = optarg;
 259                         break;
 260
 261                 case 'O':
 262                         Oflag = 0;
 263                         break;
 264
 265                 case 'm': {
 266                         bpf_u_int32 addr;
 267
 268                         switch (inet_pton(AF_INET, optarg, &addr)) {
 269
 270                         case 0:
 271                                 error("invalid netmask %s", optarg);
 272                                 break;
 273
 274                         case -1:
 275                                 error("invalid netmask %s: %s", optarg,
 276                                     pcap_strerror(errno));
 277                                 break;
 278
 279                         case 1:
 280                                 netmask = addr;
 281                                 break;
 282                         }
 283                         break;
 284                 }
 285
 286                 case 's': {
 287                         char *end;
 288                         long long_snaplen;
 289
 290                         long_snaplen = strtol(optarg, &end, 0);
 291                         if (optarg == end || *end != '\0'
 292                             || long_snaplen < 0
 293                             || long_snaplen > MAXIMUM_SNAPLEN)
 294                                 error("invalid snaplen %s", optarg);
 295                         else {
 296                                 if (snaplen == 0)
 297                                         snaplen = MAXIMUM_SNAPLEN;
 298                                 else
 299                                         snaplen = (int)long_snaplen;
 300                         }
 301                         break;
 302                 }
 303
 304                 default:
 305                         usage();
 306                         /* NOTREACHED */
 307                 }
 308         }
 309
 310         if (optind >= argc) {
 311                 usage();
 312                 /* NOTREACHED */
 313         }
 314
 315         dlt = pcap_datalink_name_to_val(argv[optind]);
 316         if (dlt < 0) {
 317                 dlt = (int)strtol(argv[optind], &p, 10);
 318                 if (p == argv[optind] || *p != '\0')
 319                         error("invalid data link type %s", argv[optind]);
 320         }
 321
 322         if (infile)
 323                 cmdbuf = read_infile(infile);
 324         else
 325                 cmdbuf = copy_argv(&argv[optind+1]);
 326
 327 #ifdef BDEBUG
 328         pcap_set_optimizer_debug(dflag);
 329         pcap_set_print_dot_graph(gflag);
 330 #endif
 331
 332         pd = pcap_open_dead(dlt, snaplen);
 333         if (pd == NULL)
 334                 error("Can't open fake pcap_t");
 335
 336         if (pcap_compile(pd, &fcode, cmdbuf, Oflag, netmask) < 0)
 337                 error("%s", pcap_geterr(pd));
 338
 339         have_fcode = 1;
 340         if (!bpf_validate(fcode.bf_insns, fcode.bf_len))
 341                 warn("Filter doesn't pass validation");
 342
 343 #ifdef BDEBUG
 344         if (cmdbuf != NULL) {
 345                 // replace line feed with space
 346                 for (cp = cmdbuf; *cp != '\0'; ++cp) {
 347                         if (*cp == '\r' || *cp == '\n') {
 348                                 *cp = ' ';
 349                         }
 350                 }
 351                 // only show machine code if BDEBUG defined, since dflag > 3
 352                 printf("machine codes for filter: %s\n", cmdbuf);
 353         } else
 354                 printf("machine codes for empty filter:\n");
 355 #endif
 356
 357         bpf_dump(&fcode, dflag);
 358         free(cmdbuf);
 359         if (have_fcode)
 360                 pcap_freecode (&fcode);
 361         pcap_close(pd);
 362         exit(0);
 363 }
 364
 365 static void
 366 usage(void)
 367 {
 368         (void)fprintf(stderr, "%s, with %s\n", program_name,
 369             pcap_lib_version());
 370         (void)fprintf(stderr,
 371 #ifdef BDEBUG
 372             "Usage: %s [-dgO] [ -F file ] [ -m netmask] [ -s snaplen ] dlt [ expression ]\n",
 373 #else
 374             "Usage: %s [-dO] [ -F file ] [ -m netmask] [ -s snaplen ] dlt [ expression ]\n",
 375 #endif
 376             program_name);
 377         exit(1);
 378 }