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 #ifndef lint 23 static const char copyright[] _U_ = 24 "@(#) Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 2000\n\ 25 The Regents of the University of California. All rights reserved.\n"; 26 #endif 27 28 #ifdef HAVE_CONFIG_H 29 #include "config.h" 30 #endif 31 32 #include <pcap.h> 33 #include <stdio.h> 34 #include <stdlib.h> 35 #include <string.h> 36 #include <stdarg.h> 37 #ifdef _WIN32 38 #include "getopt.h" 39 #else 40 #include <unistd.h> 41 #endif 42 #include <fcntl.h> 43 #include <errno.h> 44 #ifdef _WIN32 45 #include <winsock2.h> 46 typedef unsigned __int32 in_addr_t; 47 #else 48 #include <arpa/inet.h> 49 #endif 50 #include <sys/types.h> 51 #include <sys/stat.h> 52 53 /* 54 * This was introduced by Clang: 55 * 56 * http://clang.llvm.org/docs/LanguageExtensions.html#has-attribute 57 * 58 * in some version (which version?); it has been picked up by GCC 5.0. 59 */ 60 #ifndef __has_attribute 61 /* 62 * It's a macro, so you can check whether it's defined to check 63 * whether it's supported. 64 * 65 * If it's not, define it to always return 0, so that we move on to 66 * the fallback checks. 67 */ 68 #define __has_attribute(x) 0 69 #endif 70 71 #if __has_attribute(noreturn) \ 72 || (defined(__GNUC__) && ((__GNUC__ * 100 + __GNUC_MINOR__) >= 205)) \ 73 || (defined(__SUNPRO_C) && (__SUNPRO_C >= 0x590)) \ 74 || (defined(__xlC__) && __xlC__ >= 0x0A01) \ 75 || (defined(__HP_aCC) && __HP_aCC >= 61000) 76 /* 77 * Compiler with support for it, or GCC 2.5 and later, or Solaris Studio 12 78 * (Sun C 5.9) and later, or IBM XL C 10.1 and later (do any earlier 79 * versions of XL C support this?), or HP aCC A.06.10 and later. 80 */ 81 #define PCAP_NORETURN __attribute((noreturn)) 82 #elif defined( _MSC_VER ) 83 #define PCAP_NORETURN __declspec(noreturn) 84 #else 85 #define PCAP_NORETURN 86 #endif 87 88 #if __has_attribute(__format__) \ 89 || (defined(__GNUC__) && ((__GNUC__ * 100 + __GNUC_MINOR__) >= 203)) \ 90 || (defined(__xlC__) && __xlC__ >= 0x0A01) \ 91 || (defined(__HP_aCC) && __HP_aCC >= 61000) 92 /* 93 * Compiler with support for it, or GCC 2.3 and later, or IBM XL C 10.1 94 * and later (do any earlier versions of XL C support this?), 95 * or HP aCC A.06.10 and later. 96 */ 97 #define PCAP_PRINTFLIKE(x,y) __attribute__((__format__(__printf__,x,y))) 98 #else 99 #define PCAP_PRINTFLIKE(x,y) 100 #endif 101 102 static char *program_name; 103 104 /* Forwards */ 105 static void PCAP_NORETURN usage(void); 106 static void PCAP_NORETURN error(const char *, ...) PCAP_PRINTFLIKE(1, 2); 107 static void warn(const char *, ...) PCAP_PRINTFLIKE(1, 2); 108 109 #ifdef BDEBUG 110 int dflag; 111 #endif 112 113 /* 114 * On Windows, we need to open the file in binary mode, so that 115 * we get all the bytes specified by the size we get from "fstat()". 116 * On UNIX, that's not necessary. O_BINARY is defined on Windows; 117 * we define it as 0 if it's not defined, so it does nothing. 118 */ 119 #ifndef O_BINARY 120 #define O_BINARY 0 121 #endif 122 123 static char * 124 read_infile(char *fname) 125 { 126 register int i, fd, cc; 127 register char *cp; 128 struct stat buf; 129 130 fd = open(fname, O_RDONLY|O_BINARY); 131 if (fd < 0) 132 error("can't open %s: %s", fname, pcap_strerror(errno)); 133 134 if (fstat(fd, &buf) < 0) 135 error("can't stat %s: %s", fname, pcap_strerror(errno)); 136 137 cp = malloc((u_int)buf.st_size + 1); 138 if (cp == NULL) 139 error("malloc(%d) for %s: %s", (u_int)buf.st_size + 1, 140 fname, pcap_strerror(errno)); 141 cc = read(fd, cp, (u_int)buf.st_size); 142 if (cc < 0) 143 error("read %s: %s", fname, pcap_strerror(errno)); 144 if (cc != buf.st_size) 145 error("short read %s (%d != %d)", fname, cc, (int)buf.st_size); 146 147 close(fd); 148 /* replace "# comment" with spaces */ 149 for (i = 0; i < cc; i++) { 150 if (cp[i] == '#') 151 while (i < cc && cp[i] != '\n') 152 cp[i++] = ' '; 153 } 154 cp[cc] = '\0'; 155 return (cp); 156 } 157 158 /* VARARGS */ 159 static void 160 error(const char *fmt, ...) 161 { 162 va_list ap; 163 164 (void)fprintf(stderr, "%s: ", program_name); 165 va_start(ap, fmt); 166 (void)vfprintf(stderr, fmt, ap); 167 va_end(ap); 168 if (*fmt) { 169 fmt += strlen(fmt); 170 if (fmt[-1] != '\n') 171 (void)fputc('\n', stderr); 172 } 173 exit(1); 174 /* NOTREACHED */ 175 } 176 177 /* VARARGS */ 178 static void 179 warn(const char *fmt, ...) 180 { 181 va_list ap; 182 183 (void)fprintf(stderr, "%s: WARNING: ", program_name); 184 va_start(ap, fmt); 185 (void)vfprintf(stderr, fmt, ap); 186 va_end(ap); 187 if (*fmt) { 188 fmt += strlen(fmt); 189 if (fmt[-1] != '\n') 190 (void)fputc('\n', stderr); 191 } 192 } 193 194 /* 195 * Copy arg vector into a new buffer, concatenating arguments with spaces. 196 */ 197 static char * 198 copy_argv(register char **argv) 199 { 200 register char **p; 201 register u_int len = 0; 202 char *buf; 203 char *src, *dst; 204 205 p = argv; 206 if (*p == 0) 207 return 0; 208 209 while (*p) 210 len += strlen(*p++) + 1; 211 212 buf = (char *)malloc(len); 213 if (buf == NULL) 214 error("copy_argv: malloc"); 215 216 p = argv; 217 dst = buf; 218 while ((src = *p++) != NULL) { 219 while ((*dst++ = *src++) != '\0') 220 ; 221 dst[-1] = ' '; 222 } 223 dst[-1] = '\0'; 224 225 return buf; 226 } 227 228 int 229 main(int argc, char **argv) 230 { 231 char *cp; 232 int op; 233 #ifndef BDEBUG 234 int dflag; 235 #endif 236 char *infile; 237 int Oflag; 238 long snaplen; 239 char *p; 240 int dlt; 241 bpf_u_int32 netmask = PCAP_NETMASK_UNKNOWN; 242 char *cmdbuf; 243 pcap_t *pd; 244 struct bpf_program fcode; 245 246 #ifdef _WIN32 247 if(wsockinit() != 0) return 1; 248 #endif /* _WIN32 */ 249 250 #ifndef BDEBUG 251 dflag = 1; 252 #else 253 /* if optimizer debugging is enabled, output DOT graph 254 * `dflag=4' is equivalent to -dddd to follow -d/-dd/-ddd 255 * convention in tcpdump command line 256 */ 257 dflag = 4; 258 #endif 259 infile = NULL; 260 Oflag = 1; 261 snaplen = 68; 262 263 if ((cp = strrchr(argv[0], '/')) != NULL) 264 program_name = cp + 1; 265 else 266 program_name = argv[0]; 267 268 opterr = 0; 269 while ((op = getopt(argc, argv, "dF:m:Os:")) != -1) { 270 switch (op) { 271 272 case 'd': 273 ++dflag; 274 break; 275 276 case 'F': 277 infile = optarg; 278 break; 279 280 case 'O': 281 Oflag = 0; 282 break; 283 284 case 'm': { 285 in_addr_t addr; 286 287 addr = inet_addr(optarg); 288 if (addr == (in_addr_t)(-1)) 289 error("invalid netmask %s", optarg); 290 netmask = addr; 291 break; 292 } 293 294 case 's': { 295 char *end; 296 297 snaplen = strtol(optarg, &end, 0); 298 if (optarg == end || *end != '\0' 299 || snaplen < 0 || snaplen > 65535) 300 error("invalid snaplen %s", optarg); 301 else if (snaplen == 0) 302 snaplen = 65535; 303 break; 304 } 305 306 default: 307 usage(); 308 /* NOTREACHED */ 309 } 310 } 311 312 if (optind >= argc) { 313 usage(); 314 /* NOTREACHED */ 315 } 316 317 dlt = pcap_datalink_name_to_val(argv[optind]); 318 if (dlt < 0) { 319 dlt = (int)strtol(argv[optind], &p, 10); 320 if (p == argv[optind] || *p != '\0') 321 error("invalid data link type %s", argv[optind]); 322 } 323 324 if (infile) 325 cmdbuf = read_infile(infile); 326 else 327 cmdbuf = copy_argv(&argv[optind+1]); 328 329 pd = pcap_open_dead(dlt, snaplen); 330 if (pd == NULL) 331 error("Can't open fake pcap_t"); 332 333 if (pcap_compile(pd, &fcode, cmdbuf, Oflag, netmask) < 0) 334 error("%s", pcap_geterr(pd)); 335 336 if (!bpf_validate(fcode.bf_insns, fcode.bf_len)) 337 warn("Filter doesn't pass validation"); 338 339 #ifdef BDEBUG 340 // replace line feed with space 341 for (cp = cmdbuf; *cp != '\0'; ++cp) { 342 if (*cp == '\r' || *cp == '\n') { 343 *cp = ' '; 344 } 345 } 346 // only show machine code if BDEBUG defined, since dflag > 3 347 printf("machine codes for filter: %s\n", cmdbuf); 348 #endif 349 350 bpf_dump(&fcode, dflag); 351 pcap_close(pd); 352 exit(0); 353 } 354 355 static void 356 usage(void) 357 { 358 (void)fprintf(stderr, "%s, with %s\n", program_name, 359 pcap_lib_version()); 360 (void)fprintf(stderr, 361 "Usage: %s [-dO] [ -F file ] [ -m netmask] [ -s snaplen ] dlt [ expression ]\n", 362 program_name); 363 exit(1); 364 } 365
