1 /* 2 * Copyright (c) 1994, 1995, 1996 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 the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the Computer Systems 16 * Engineering Group at Lawrence Berkeley Laboratory. 17 * 4. Neither the name of the University nor of the Laboratory may be used 18 * to endorse or promote products derived from this software without 19 * specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 */ 33 34 #ifndef pcap_int_h 35 #define pcap_int_h 36 37 #include <pcap/pcap.h> 38 39 #ifdef __cplusplus 40 extern "C" { 41 #endif 42 43 #ifdef WIN32 44 #include <Packet32.h> 45 extern CRITICAL_SECTION g_PcapCompileCriticalSection; 46 #endif /* WIN32 */ 47 48 #ifdef MSDOS 49 #include <fcntl.h> 50 #include <io.h> 51 #endif 52 53 #if (defined(_MSC_VER) && (_MSC_VER <= 1200)) /* we are compiling with Visual Studio 6, that doesn't support the LL suffix*/ 54 55 /* 56 * Swap byte ordering of unsigned long long timestamp on a big endian 57 * machine. 58 */ 59 #define SWAPLL(ull) ((ull & 0xff00000000000000) >> 56) | \ 60 ((ull & 0x00ff000000000000) >> 40) | \ 61 ((ull & 0x0000ff0000000000) >> 24) | \ 62 ((ull & 0x000000ff00000000) >> 8) | \ 63 ((ull & 0x00000000ff000000) << 8) | \ 64 ((ull & 0x0000000000ff0000) << 24) | \ 65 ((ull & 0x000000000000ff00) << 40) | \ 66 ((ull & 0x00000000000000ff) << 56) 67 68 #else /* A recent Visual studio compiler or not VC */ 69 70 /* 71 * Swap byte ordering of unsigned long long timestamp on a big endian 72 * machine. 73 */ 74 #define SWAPLL(ull) ((ull & 0xff00000000000000LL) >> 56) | \ 75 ((ull & 0x00ff000000000000LL) >> 40) | \ 76 ((ull & 0x0000ff0000000000LL) >> 24) | \ 77 ((ull & 0x000000ff00000000LL) >> 8) | \ 78 ((ull & 0x00000000ff000000LL) << 8) | \ 79 ((ull & 0x0000000000ff0000LL) << 24) | \ 80 ((ull & 0x000000000000ff00LL) << 40) | \ 81 ((ull & 0x00000000000000ffLL) << 56) 82 83 #endif /* _MSC_VER */ 84 85 /* 86 * Maximum snapshot length. 87 * 88 * Somewhat arbitrary, but chosen to be: 89 * 90 * 1) big enough for maximum-size Linux loopback packets (65549) 91 * and some USB packets captured with USBPcap: 92 * 93 * http://desowin.org/usbpcap/ 94 * 95 * (> 131072, < 262144) 96 * 97 * and 98 * 99 * 2) small enough not to cause attempts to allocate huge amounts of 100 * memory; some applications might use the snapshot length in a 101 * savefile header to control the size of the buffer they allocate, 102 * so a size of, say, 2^31-1 might not work well. 103 * 104 * We don't enforce this in pcap_set_snaplen(), but we use it internally. 105 */ 106 #define MAXIMUM_SNAPLEN 262144 107 108 struct pcap_opt { 109 char *source; 110 int timeout; /* timeout for buffering */ 111 int buffer_size; 112 int promisc; 113 int rfmon; /* monitor mode */ 114 int immediate; /* immediate mode - deliver packets as soon as they arrive */ 115 int tstamp_type; 116 int tstamp_precision; 117 }; 118 119 typedef int (*activate_op_t)(pcap_t *); 120 typedef int (*can_set_rfmon_op_t)(pcap_t *); 121 typedef int (*read_op_t)(pcap_t *, int cnt, pcap_handler, u_char *); 122 typedef int (*inject_op_t)(pcap_t *, const void *, size_t); 123 typedef int (*setfilter_op_t)(pcap_t *, struct bpf_program *); 124 typedef int (*setdirection_op_t)(pcap_t *, pcap_direction_t); 125 typedef int (*set_datalink_op_t)(pcap_t *, int); 126 typedef int (*getnonblock_op_t)(pcap_t *, char *); 127 typedef int (*setnonblock_op_t)(pcap_t *, int, char *); 128 typedef int (*stats_op_t)(pcap_t *, struct pcap_stat *); 129 #ifdef WIN32 130 typedef int (*setbuff_op_t)(pcap_t *, int); 131 typedef int (*setmode_op_t)(pcap_t *, int); 132 typedef int (*setmintocopy_op_t)(pcap_t *, int); 133 typedef Adapter *(*getadapter_op_t)(pcap_t *); 134 #endif 135 typedef void (*cleanup_op_t)(pcap_t *); 136 137 /* 138 * We put all the stuff used in the read code path at the beginning, 139 * to try to keep it together in the same cache line or lines. 140 */ 141 struct pcap { 142 /* 143 * Method to call to read packets on a live capture. 144 */ 145 read_op_t read_op; 146 147 /* 148 * Method to call to read to read packets from a savefile. 149 */ 150 int (*next_packet_op)(pcap_t *, struct pcap_pkthdr *, u_char **); 151 152 #ifdef WIN32 153 ADAPTER *adapter; 154 LPPACKET Packet; 155 int nonblock; 156 #else 157 int fd; 158 int selectable_fd; 159 #endif /* WIN32 */ 160 161 /* 162 * Read buffer. 163 */ 164 int bufsize; 165 u_char *buffer; 166 u_char *bp; 167 int cc; 168 169 int break_loop; /* flag set to force break from packet-reading loop */ 170 171 void *priv; /* private data for methods */ 172 173 int swapped; 174 FILE *rfile; /* null if live capture, non-null if savefile */ 175 int fddipad; 176 struct pcap *next; /* list of open pcaps that need stuff cleared on close */ 177 178 /* 179 * File version number; meaningful only for a savefile, but we 180 * keep it here so that apps that (mistakenly) ask for the 181 * version numbers will get the same zero values that they 182 * always did. 183 */ 184 int version_major; 185 int version_minor; 186 187 int snapshot; 188 int linktype; /* Network linktype */ 189 int linktype_ext; /* Extended information stored in the linktype field of a file */ 190 int tzoff; /* timezone offset */ 191 int offset; /* offset for proper alignment */ 192 int activated; /* true if the capture is really started */ 193 int oldstyle; /* if we're opening with pcap_open_live() */ 194 195 struct pcap_opt opt; 196 197 /* 198 * Place holder for pcap_next(). 199 */ 200 u_char *pkt; 201 202 /* We're accepting only packets in this direction/these directions. */ 203 pcap_direction_t direction; 204 205 /* 206 * Flags to affect BPF code generation. 207 */ 208 int bpf_codegen_flags; 209 210 /* 211 * Placeholder for filter code if bpf not in kernel. 212 */ 213 struct bpf_program fcode; 214 215 char errbuf[PCAP_ERRBUF_SIZE + 1]; 216 int dlt_count; 217 u_int *dlt_list; 218 int tstamp_type_count; 219 u_int *tstamp_type_list; 220 int tstamp_precision_count; 221 u_int *tstamp_precision_list; 222 223 struct pcap_pkthdr pcap_header; /* This is needed for the pcap_next_ex() to work */ 224 225 /* 226 * More methods. 227 */ 228 activate_op_t activate_op; 229 can_set_rfmon_op_t can_set_rfmon_op; 230 inject_op_t inject_op; 231 setfilter_op_t setfilter_op; 232 setdirection_op_t setdirection_op; 233 set_datalink_op_t set_datalink_op; 234 getnonblock_op_t getnonblock_op; 235 setnonblock_op_t setnonblock_op; 236 stats_op_t stats_op; 237 238 /* 239 * Routine to use as callback for pcap_next()/pcap_next_ex(). 240 */ 241 pcap_handler oneshot_callback; 242 243 #ifdef WIN32 244 /* 245 * These are, at least currently, specific to the Win32 NPF 246 * driver. 247 */ 248 setbuff_op_t setbuff_op; 249 setmode_op_t setmode_op; 250 setmintocopy_op_t setmintocopy_op; 251 getadapter_op_t getadapter_op; 252 #endif 253 cleanup_op_t cleanup_op; 254 }; 255 256 /* 257 * BPF code generation flags. 258 */ 259 #define BPF_SPECIAL_VLAN_HANDLING 0x00000001 /* special VLAN handling for Linux */ 260 261 /* 262 * This is a timeval as stored in a savefile. 263 * It has to use the same types everywhere, independent of the actual 264 * `struct timeval'; `struct timeval' has 32-bit tv_sec values on some 265 * platforms and 64-bit tv_sec values on other platforms, and writing 266 * out native `struct timeval' values would mean files could only be 267 * read on systems with the same tv_sec size as the system on which 268 * the file was written. 269 */ 270 271 struct pcap_timeval { 272 bpf_int32 tv_sec; /* seconds */ 273 bpf_int32 tv_usec; /* microseconds */ 274 }; 275 276 /* 277 * This is a `pcap_pkthdr' as actually stored in a savefile. 278 * 279 * Do not change the format of this structure, in any way (this includes 280 * changes that only affect the length of fields in this structure), 281 * and do not make the time stamp anything other than seconds and 282 * microseconds (e.g., seconds and nanoseconds). Instead: 283 * 284 * introduce a new structure for the new format; 285 * 286 * send mail to "tcpdump-workers (at) lists.tcpdump.org", requesting 287 * a new magic number for your new capture file format, and, when 288 * you get the new magic number, put it in "savefile.c"; 289 * 290 * use that magic number for save files with the changed record 291 * header; 292 * 293 * make the code in "savefile.c" capable of reading files with 294 * the old record header as well as files with the new record header 295 * (using the magic number to determine the header format). 296 * 297 * Then supply the changes by forking the branch at 298 * 299 * https://github.com/the-tcpdump-group/libpcap/issues 300 * 301 * and issuing a pull request, so that future versions of libpcap and 302 * programs that use it (such as tcpdump) will be able to read your new 303 * capture file format. 304 */ 305 306 struct pcap_sf_pkthdr { 307 struct pcap_timeval ts; /* time stamp */ 308 bpf_u_int32 caplen; /* length of portion present */ 309 bpf_u_int32 len; /* length this packet (off wire) */ 310 }; 311 312 /* 313 * How a `pcap_pkthdr' is actually stored in savefiles written 314 * by some patched versions of libpcap (e.g. the ones in Red 315 * Hat Linux 6.1 and 6.2). 316 * 317 * Do not change the format of this structure, in any way (this includes 318 * changes that only affect the length of fields in this structure). 319 * Instead, introduce a new structure, as per the above. 320 */ 321 322 struct pcap_sf_patched_pkthdr { 323 struct pcap_timeval ts; /* time stamp */ 324 bpf_u_int32 caplen; /* length of portion present */ 325 bpf_u_int32 len; /* length this packet (off wire) */ 326 int index; 327 unsigned short protocol; 328 unsigned char pkt_type; 329 }; 330 331 /* 332 * User data structure for the one-shot callback used for pcap_next() 333 * and pcap_next_ex(). 334 */ 335 struct oneshot_userdata { 336 struct pcap_pkthdr *hdr; 337 const u_char **pkt; 338 pcap_t *pd; 339 }; 340 341 int yylex(void); 342 343 #ifndef min 344 #define min(a, b) ((a) > (b) ? (b) : (a)) 345 #endif 346 347 /* XXX should these be in pcap.h? */ 348 int pcap_offline_read(pcap_t *, int, pcap_handler, u_char *); 349 int pcap_read(pcap_t *, int cnt, pcap_handler, u_char *); 350 351 #ifndef HAVE_STRLCPY 352 #define strlcpy(x, y, z) \ 353 (strncpy((x), (y), (z)), \ 354 ((z) <= 0 ? 0 : ((x)[(z) - 1] = '\0')), \ 355 strlen((y))) 356 #endif 357 358 #include <stdarg.h> 359 360 #if !defined(HAVE_SNPRINTF) 361 #define snprintf pcap_snprintf 362 extern int snprintf (char *, size_t, const char *, ...); 363 #endif 364 365 #if !defined(HAVE_VSNPRINTF) 366 #define vsnprintf pcap_vsnprintf 367 extern int vsnprintf (char *, size_t, const char *, va_list ap); 368 #endif 369 370 /* 371 * Does the packet count argument to a module's read routine say 372 * "supply packets until you run out of packets"? 373 */ 374 #define PACKET_COUNT_IS_UNLIMITED(count) ((count) <= 0) 375 376 /* 377 * Routines that most pcap implementations can use for non-blocking mode. 378 */ 379 #if !defined(WIN32) && !defined(MSDOS) 380 int pcap_getnonblock_fd(pcap_t *, char *); 381 int pcap_setnonblock_fd(pcap_t *p, int, char *); 382 #endif 383 384 /* 385 * Internal interfaces for "pcap_create()". 386 * 387 * "pcap_create_interface()" is the routine to do a pcap_create on 388 * a regular network interface. There are multiple implementations 389 * of this, one for each platform type (Linux, BPF, DLPI, etc.), 390 * with the one used chosen by the configure script. 391 * 392 * "pcap_create_common()" allocates and fills in a pcap_t, for use 393 * by pcap_create routines. 394 */ 395 pcap_t *pcap_create_interface(const char *, char *); 396 pcap_t *pcap_create_common(const char *, char *, size_t); 397 int pcap_do_addexit(pcap_t *); 398 void pcap_add_to_pcaps_to_close(pcap_t *); 399 void pcap_remove_from_pcaps_to_close(pcap_t *); 400 void pcap_cleanup_live_common(pcap_t *); 401 int pcap_not_initialized(pcap_t *); 402 int pcap_check_activated(pcap_t *); 403 404 /* 405 * Internal interfaces for "pcap_findalldevs()". 406 * 407 * "pcap_findalldevs_interfaces()" finds interfaces using the 408 * "standard" mechanisms (SIOCGIFCONF, "getifaddrs()", etc.). 409 * 410 * "pcap_platform_finddevs()" is a platform-dependent routine to 411 * add devices not found by the "standard" mechanisms. 412 * 413 * "pcap_add_if()" adds an interface to the list of interfaces, for 414 * use by various "find interfaces" routines. 415 */ 416 int pcap_findalldevs_interfaces(pcap_if_t **, char *); 417 int pcap_platform_finddevs(pcap_if_t **, char *); 418 int add_addr_to_iflist(pcap_if_t **, const char *, u_int, struct sockaddr *, 419 size_t, struct sockaddr *, size_t, struct sockaddr *, size_t, 420 struct sockaddr *, size_t, char *); 421 int add_addr_to_dev(pcap_if_t *, struct sockaddr *, size_t, 422 struct sockaddr *, size_t, struct sockaddr *, size_t, 423 struct sockaddr *dstaddr, size_t, char *errbuf); 424 int pcap_add_if(pcap_if_t **, const char *, u_int, const char *, char *); 425 struct sockaddr *dup_sockaddr(struct sockaddr *, size_t); 426 int add_or_find_if(pcap_if_t **, pcap_if_t **, const char *, u_int, 427 const char *, char *); 428 429 /* 430 * Internal interfaces for "pcap_open_offline()". 431 * 432 * "pcap_open_offline_common()" allocates and fills in a pcap_t, for use 433 * by pcap_open_offline routines. 434 * 435 * "sf_cleanup()" closes the file handle associated with a pcap_t, if 436 * appropriate, and frees all data common to all modules for handling 437 * savefile types. 438 */ 439 pcap_t *pcap_open_offline_common(char *ebuf, size_t size); 440 void sf_cleanup(pcap_t *p); 441 442 /* 443 * Internal interfaces for both "pcap_create()" and routines that 444 * open savefiles. 445 * 446 * "pcap_oneshot()" is the standard one-shot callback for "pcap_next()" 447 * and "pcap_next_ex()". 448 */ 449 void pcap_oneshot(u_char *, const struct pcap_pkthdr *, const u_char *); 450 451 #ifdef WIN32 452 char *pcap_win32strerror(void); 453 #endif 454 455 int install_bpf_program(pcap_t *, struct bpf_program *); 456 457 int pcap_strcasecmp(const char *, const char *); 458 459 #ifdef __cplusplus 460 } 461 #endif 462 463 #endif 464
