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 #ifdef _WIN32
  40   #include "getopt.h"
  41   #include "unix.h"
  42 #else
  43   #include <unistd.h>
  44 #endif
  45 #include <fcntl.h>
  46 #include <errno.h>
  47 #ifdef _WIN32
  48   #include <winsock2.h>
  49   #include <ws2tcpip.h>
  50 #else
  51   #include <sys/socket.h>
  52   #include <arpa/inet.h>
  53 #endif
  54 #include <sys/types.h>
  55 #include <sys/stat.h>
  56
  57 #include "pcap/funcattrs.h"
  58
  59 #ifdef BDEBUG
  60 /*
  61  * We have pcap_set_optimizer_debug() in libpcap; declare it (it's not declared
  62  * by any libpcap header, because it's a special hack, only available if
  63  * libpcap was configured to include it, and only intended for use by
  64  * libpcap developers trying to debug the optimizer for filter expressions).
  65  */
  66 PCAP_API void pcap_set_optimizer_debug(int);
  67 #endif
  68
  69 static char *program_name;
  70
  71 /* Forwards */
  72 static void PCAP_NORETURN usage(void);
  73 static void PCAP_NORETURN error(const char *, ...) PCAP_PRINTFLIKE(1, 2);
  74 static void warn(const char *, ...) PCAP_PRINTFLIKE(1, 2);
  75
  76 /*
  77  * On Windows, we need to open the file in binary mode, so that
  78  * we get all the bytes specified by the size we get from "fstat()".
  79  * On UNIX, that's not necessary.  O_BINARY is defined on Windows;
  80  * we define it as 0 if it's not defined, so it does nothing.
  81  */
  82 #ifndef O_BINARY
  83 #define O_BINARY        0
  84 #endif
  85
  86 static char *
  87 read_infile(char *fname)
  88 {
  89         register int i, fd, cc;
  90         register char *cp;
  91         struct stat buf;
  92
  93         fd = open(fname, O_RDONLY|O_BINARY);
  94         if (fd < 0)
  95                 error("can't open %s: %s", fname, pcap_strerror(errno));
  96
  97         if (fstat(fd, &buf) < 0)
  98                 error("can't stat %s: %s", fname, pcap_strerror(errno));
  99
 100         cp = malloc((u_int)buf.st_size + 1);
 101         if (cp == NULL)
 102                 error("malloc(%d) for %s: %s", (u_int)buf.st_size + 1,
 103                         fname, pcap_strerror(errno));
 104         cc = read(fd, cp, (u_int)buf.st_size);
 105         if (cc < 0)
 106                 error("read %s: %s", fname, pcap_strerror(errno));
 107         if (cc != buf.st_size)
 108                 error("short read %s (%d != %d)", fname, cc, (int)buf.st_size);
 109
 110         close(fd);
 111         /* replace "# comment" with spaces */
 112         for (i = 0; i < cc; i++) {
 113                 if (cp[i] == '#')
 114                         while (i < cc && cp[i] != '\n')
 115                                 cp[i++] = ' ';
 116         }
 117         cp[cc] = '\0';
 118         return (cp);
 119 }
 120
 121 /* VARARGS */
 122 static void
 123 error(const char *fmt, ...)
 124 {
 125         va_list ap;
 126
 127         (void)fprintf(stderr, "%s: ", program_name);
 128         va_start(ap, fmt);
 129         (void)vfprintf(stderr, fmt, ap);
 130         va_end(ap);
 131         if (*fmt) {
 132                 fmt += strlen(fmt);
 133                 if (fmt[-1] != '\n')
 134                         (void)fputc('\n', stderr);
 135         }
 136         exit(1);
 137         /* NOTREACHED */
 138 }
 139
 140 /* VARARGS */
 141 static void
 142 warn(const char *fmt, ...)
 143 {
 144         va_list ap;
 145
 146         (void)fprintf(stderr, "%s: WARNING: ", program_name);
 147         va_start(ap, fmt);
 148         (void)vfprintf(stderr, fmt, ap);
 149         va_end(ap);
 150         if (*fmt) {
 151                 fmt += strlen(fmt);
 152                 if (fmt[-1] != '\n')
 153                         (void)fputc('\n', stderr);
 154         }
 155 }
 156
 157 /*
 158  * Copy arg vector into a new buffer, concatenating arguments with spaces.
 159  */
 160 static char *
 161 copy_argv(register char **argv)
 162 {
 163         register char **p;
 164         register u_int len = 0;
 165         char *buf;
 166         char *src, *dst;
 167
 168         p = argv;
 169         if (*p == 0)
 170                 return 0;
 171
 172         while (*p)
 173                 len += strlen(*p++) + 1;
 174
 175         buf = (char *)malloc(len);
 176         if (buf == NULL)
 177                 error("copy_argv: malloc");
 178
 179         p = argv;
 180         dst = buf;
 181         while ((src = *p++) != NULL) {
 182                 while ((*dst++ = *src++) != '\0')
 183                         ;
 184                 dst[-1] = ' ';
 185         }
 186         dst[-1] = '\0';
 187
 188         return buf;
 189 }
 190
 191 int
 192 main(int argc, char **argv)
 193 {
 194         char *cp;
 195         int op;
 196         int dflag;
 197         char *infile;
 198         int Oflag;
 199         long snaplen;
 200         char *p;
 201         int dlt;
 202         int have_fcode = 0;
 203         bpf_u_int32 netmask = PCAP_NETMASK_UNKNOWN;
 204         char *cmdbuf;
 205         pcap_t *pd;
 206         struct bpf_program fcode;
 207
 208 #ifdef _WIN32
 209         if (pcap_wsockinit() != 0)
 210                 return 1;
 211 #endif /* _WIN32 */
 212
 213 #ifndef BDEBUG
 214         dflag = 1;
 215 #else
 216         /* if optimizer debugging is enabled, output DOT graph
 217          * `dflag=4' is equivalent to -dddd to follow -d/-dd/-ddd
 218          * convention in tcpdump command line
 219          */
 220         dflag = 4;
 221 #endif
 222         infile = NULL;
 223         Oflag = 1;
 224         snaplen = 68;
 225
 226         if ((cp = strrchr(argv[0], '/')) != NULL)
 227                 program_name = cp + 1;
 228         else
 229                 program_name = argv[0];
 230
 231         opterr = 0;
 232         while ((op = getopt(argc, argv, "dF:m:Os:")) != -1) {
 233                 switch (op) {
 234
 235                 case 'd':
 236                         ++dflag;
 237                         break;
 238
 239                 case 'F':
 240                         infile = optarg;
 241                         break;
 242
 243                 case 'O':
 244                         Oflag = 0;
 245                         break;
 246
 247                 case 'm': {
 248                         bpf_u_int32 addr;
 249
 250                         switch (inet_pton(AF_INET, optarg, &addr)) {
 251
 252                         case 0:
 253                                 error("invalid netmask %s", optarg);
 254                                 break;
 255
 256                         case -1:
 257                                 error("invalid netmask %s: %s", optarg,
 258                                     pcap_strerror(errno));
 259                                 break;
 260
 261                         case 1:
 262                                 netmask = addr;
 263                                 break;
 264                         }
 265                         break;
 266                 }
 267
 268                 case 's': {
 269                         char *end;
 270
 271                         snaplen = strtol(optarg, &end, 0);
 272                         if (optarg == end || *end != '\0'
 273                             || snaplen < 0 || snaplen > 65535)
 274                                 error("invalid snaplen %s", optarg);
 275                         else if (snaplen == 0)
 276                                 snaplen = 65535;
 277                         break;
 278                 }
 279
 280                 default:
 281                         usage();
 282                         /* NOTREACHED */
 283                 }
 284         }
 285
 286         if (optind >= argc) {
 287                 usage();
 288                 /* NOTREACHED */
 289         }
 290
 291         dlt = pcap_datalink_name_to_val(argv[optind]);
 292         if (dlt < 0) {
 293                 dlt = (int)strtol(argv[optind], &p, 10);
 294                 if (p == argv[optind] || *p != '\0')
 295                         error("invalid data link type %s", argv[optind]);
 296         }
 297
 298         if (infile)
 299                 cmdbuf = read_infile(infile);
 300         else
 301                 cmdbuf = copy_argv(&argv[optind+1]);
 302
 303 #ifdef BDEBUG
 304         pcap_set_optimizer_debug(dflag);
 305 #endif
 306
 307         pd = pcap_open_dead(dlt, snaplen);
 308         if (pd == NULL)
 309                 error("Can't open fake pcap_t");
 310
 311         if (pcap_compile(pd, &fcode, cmdbuf, Oflag, netmask) < 0)
 312                 error("%s", pcap_geterr(pd));
 313
 314         have_fcode = 1;
 315         if (!bpf_validate(fcode.bf_insns, fcode.bf_len))
 316                 warn("Filter doesn't pass validation");
 317
 318 #ifdef BDEBUG
 319         if (cmdbuf != NULL) {
 320                 // replace line feed with space
 321                 for (cp = cmdbuf; *cp != '\0'; ++cp) {
 322                         if (*cp == '\r' || *cp == '\n') {
 323                                 *cp = ' ';
 324                         }
 325                 }
 326                 // only show machine code if BDEBUG defined, since dflag > 3
 327                 printf("machine codes for filter: %s\n", cmdbuf);
 328         } else
 329                 printf("machine codes for empty filter:\n");
 330 #endif
 331
 332         bpf_dump(&fcode, dflag);
 333         free(cmdbuf);
 334         if (have_fcode)
 335                 pcap_freecode (&fcode);
 336         pcap_close(pd);
 337         exit(0);
 338 }
 339
 340 static void
 341 usage(void)
 342 {
 343         (void)fprintf(stderr, "%s, with %s\n", program_name,
 344             pcap_lib_version());
 345         (void)fprintf(stderr,
 346             "Usage: %s [-dO] [ -F file ] [ -m netmask] [ -s snaplen ] dlt [ expression ]\n",
 347             program_name);
 348         exit(1);
 349 }