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 /* 29 * Tests how select() and poll() behave on the selectable file descriptor 30 * for a pcap_t. 31 * 32 * This would be significantly different on Windows, as it'd test 33 * how WaitForMultipleObjects() would work on the event handle for a 34 * pcap_t. 35 */ 36 #include <pcap.h> 37 #include <stdio.h> 38 #include <stdlib.h> 39 #include <string.h> 40 #include <stdarg.h> 41 #include <unistd.h> 42 #include <errno.h> 43 #include <sys/types.h> 44 #ifdef HAVE_SYS_SELECT_H 45 #include <sys/select.h> 46 #else 47 #include <sys/time.h> /* older UN*Xes */ 48 #endif 49 #include <poll.h> 50 51 char *program_name; 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 /* Forwards */ 103 static void countme(u_char *, const struct pcap_pkthdr *, const u_char *); 104 static void PCAP_NORETURN usage(void); 105 static void PCAP_NORETURN error(const char *, ...) PCAP_PRINTFLIKE(1, 2); 106 static void warning(const char *, ...) PCAP_PRINTFLIKE(1, 2); 107 static char *copy_argv(char **); 108 109 static pcap_t *pd; 110 111 int 112 main(int argc, char **argv) 113 { 114 register int op; 115 bpf_u_int32 localnet, netmask; 116 register char *cp, *cmdbuf, *device; 117 int doselect, dopoll, dotimeout, dononblock; 118 struct bpf_program fcode; 119 char ebuf[PCAP_ERRBUF_SIZE]; 120 int selectable_fd; 121 int status; 122 int packet_count; 123 124 device = NULL; 125 doselect = 0; 126 dopoll = 0; 127 dotimeout = 0; 128 dononblock = 0; 129 if ((cp = strrchr(argv[0], '/')) != NULL) 130 program_name = cp + 1; 131 else 132 program_name = argv[0]; 133 134 opterr = 0; 135 while ((op = getopt(argc, argv, "i:sptn")) != -1) { 136 switch (op) { 137 138 case 'i': 139 device = optarg; 140 break; 141 142 case 's': 143 doselect = 1; 144 break; 145 146 case 'p': 147 dopoll = 1; 148 break; 149 150 case 't': 151 dotimeout = 1; 152 break; 153 154 case 'n': 155 dononblock = 1; 156 break; 157 158 default: 159 usage(); 160 /* NOTREACHED */ 161 } 162 } 163 164 if (doselect && dopoll) { 165 fprintf(stderr, "selpolltest: choose select (-s) or poll (-p), but not both\n"); 166 return 1; 167 } 168 if (dotimeout && !doselect && !dopoll) { 169 fprintf(stderr, "selpolltest: timeout (-t) requires select (-s) or poll (-p)\n"); 170 return 1; 171 } 172 if (device == NULL) { 173 device = pcap_lookupdev(ebuf); 174 if (device == NULL) 175 error("%s", ebuf); 176 } 177 *ebuf = '\0'; 178 pd = pcap_open_live(device, 65535, 0, 1000, ebuf); 179 if (pd == NULL) 180 error("%s", ebuf); 181 else if (*ebuf) 182 warning("%s", ebuf); 183 if (pcap_lookupnet(device, &localnet, &netmask, ebuf) < 0) { 184 localnet = 0; 185 netmask = 0; 186 warning("%s", ebuf); 187 } 188 cmdbuf = copy_argv(&argv[optind]); 189 190 if (pcap_compile(pd, &fcode, cmdbuf, 1, netmask) < 0) 191 error("%s", pcap_geterr(pd)); 192 193 if (pcap_setfilter(pd, &fcode) < 0) 194 error("%s", pcap_geterr(pd)); 195 if (pcap_get_selectable_fd(pd) == -1) 196 error("pcap_get_selectable_fd() fails"); 197 if (dononblock) { 198 if (pcap_setnonblock(pd, 1, ebuf) == -1) 199 error("pcap_setnonblock failed: %s", ebuf); 200 } 201 selectable_fd = pcap_get_selectable_fd(pd); 202 printf("Listening on %s\n", device); 203 if (doselect) { 204 for (;;) { 205 fd_set setread, setexcept; 206 struct timeval seltimeout; 207 208 FD_ZERO(&setread); 209 FD_SET(selectable_fd, &setread); 210 FD_ZERO(&setexcept); 211 FD_SET(selectable_fd, &setexcept); 212 if (dotimeout) { 213 seltimeout.tv_sec = 0; 214 seltimeout.tv_usec = 1000; 215 status = select(selectable_fd + 1, &setread, 216 NULL, &setexcept, &seltimeout); 217 } else { 218 status = select(selectable_fd + 1, &setread, 219 NULL, &setexcept, NULL); 220 } 221 if (status == -1) { 222 printf("Select returns error (%s)\n", 223 strerror(errno)); 224 } else { 225 if (status == 0) 226 printf("Select timed out: "); 227 else 228 printf("Select returned a descriptor: "); 229 if (FD_ISSET(selectable_fd, &setread)) 230 printf("readable, "); 231 else 232 printf("not readable, "); 233 if (FD_ISSET(selectable_fd, &setexcept)) 234 printf("exceptional condition\n"); 235 else 236 printf("no exceptional condition\n"); 237 packet_count = 0; 238 status = pcap_dispatch(pd, -1, countme, 239 (u_char *)&packet_count); 240 if (status < 0) 241 break; 242 printf("%d packets seen, %d packets counted after select returns\n", 243 status, packet_count); 244 } 245 } 246 } else if (dopoll) { 247 for (;;) { 248 struct pollfd fd; 249 int polltimeout; 250 251 fd.fd = selectable_fd; 252 fd.events = POLLIN; 253 if (dotimeout) 254 polltimeout = 1; 255 else 256 polltimeout = -1; 257 status = poll(&fd, 1, polltimeout); 258 if (status == -1) { 259 printf("Poll returns error (%s)\n", 260 strerror(errno)); 261 } else { 262 if (status == 0) 263 printf("Poll timed out\n"); 264 else { 265 printf("Poll returned a descriptor: "); 266 if (fd.revents & POLLIN) 267 printf("readable, "); 268 else 269 printf("not readable, "); 270 if (fd.revents & POLLERR) 271 printf("exceptional condition, "); 272 else 273 printf("no exceptional condition, "); 274 if (fd.revents & POLLHUP) 275 printf("disconnect, "); 276 else 277 printf("no disconnect, "); 278 if (fd.revents & POLLNVAL) 279 printf("invalid\n"); 280 else 281 printf("not invalid\n"); 282 } 283 packet_count = 0; 284 status = pcap_dispatch(pd, -1, countme, 285 (u_char *)&packet_count); 286 if (status < 0) 287 break; 288 printf("%d packets seen, %d packets counted after poll returns\n", 289 status, packet_count); 290 } 291 } 292 } else { 293 for (;;) { 294 packet_count = 0; 295 status = pcap_dispatch(pd, -1, countme, 296 (u_char *)&packet_count); 297 if (status < 0) 298 break; 299 printf("%d packets seen, %d packets counted after pcap_dispatch returns\n", 300 status, packet_count); 301 } 302 } 303 if (status == -2) { 304 /* 305 * We got interrupted, so perhaps we didn't 306 * manage to finish a line we were printing. 307 * Print an extra newline, just in case. 308 */ 309 putchar('\n'); 310 } 311 (void)fflush(stdout); 312 if (status == -1) { 313 /* 314 * Error. Report it. 315 */ 316 (void)fprintf(stderr, "%s: pcap_loop: %s\n", 317 program_name, pcap_geterr(pd)); 318 } 319 pcap_close(pd); 320 exit(status == -1 ? 1 : 0); 321 } 322 323 static void 324 countme(u_char *user, const struct pcap_pkthdr *h, const u_char *sp) 325 { 326 int *counterp = (int *)user; 327 328 (*counterp)++; 329 } 330 331 static void 332 usage(void) 333 { 334 (void)fprintf(stderr, "Usage: %s [ -sptn ] [ -i interface ] [expression]\n", 335 program_name); 336 exit(1); 337 } 338 339 /* VARARGS */ 340 static void 341 error(const char *fmt, ...) 342 { 343 va_list ap; 344 345 (void)fprintf(stderr, "%s: ", program_name); 346 va_start(ap, fmt); 347 (void)vfprintf(stderr, fmt, ap); 348 va_end(ap); 349 if (*fmt) { 350 fmt += strlen(fmt); 351 if (fmt[-1] != '\n') 352 (void)fputc('\n', stderr); 353 } 354 exit(1); 355 /* NOTREACHED */ 356 } 357 358 /* VARARGS */ 359 static void 360 warning(const char *fmt, ...) 361 { 362 va_list ap; 363 364 (void)fprintf(stderr, "%s: WARNING: ", program_name); 365 va_start(ap, fmt); 366 (void)vfprintf(stderr, fmt, ap); 367 va_end(ap); 368 if (*fmt) { 369 fmt += strlen(fmt); 370 if (fmt[-1] != '\n') 371 (void)fputc('\n', stderr); 372 } 373 } 374 375 /* 376 * Copy arg vector into a new buffer, concatenating arguments with spaces. 377 */ 378 static char * 379 copy_argv(register char **argv) 380 { 381 register char **p; 382 register u_int len = 0; 383 char *buf; 384 char *src, *dst; 385 386 p = argv; 387 if (*p == 0) 388 return 0; 389 390 while (*p) 391 len += strlen(*p++) + 1; 392 393 buf = (char *)malloc(len); 394 if (buf == NULL) 395 error("copy_argv: malloc"); 396 397 p = argv; 398 dst = buf; 399 while ((src = *p++) != NULL) { 400 while ((*dst++ = *src++) != '\0') 401 ; 402 dst[-1] = ' '; 403 } 404 dst[-1] = '\0'; 405 406 return buf; 407 } 408
