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 #if defined(_WIN32) 44 /* 45 * Make sure Packet32.h doesn't define BPF structures that we've 46 * probably already defined as a result of including <pcap/pcap.h>. 47 */ 48 #define BPF_MAJOR_VERSION 49 #include <Packet32.h> 50 #elif defined(MSDOS) 51 #include <fcntl.h> 52 #include <io.h> 53 #endif 54 55 #if (defined(_MSC_VER) && (_MSC_VER <= 1200)) /* we are compiling with Visual Studio 6, that doesn't support the LL suffix*/ 56 57 /* 58 * Swap byte ordering of unsigned long long timestamp on a big endian 59 * machine. 60 */ 61 #define SWAPLL(ull) ((ull & 0xff00000000000000) >> 56) | \ 62 ((ull & 0x00ff000000000000) >> 40) | \ 63 ((ull & 0x0000ff0000000000) >> 24) | \ 64 ((ull & 0x000000ff00000000) >> 8) | \ 65 ((ull & 0x00000000ff000000) << 8) | \ 66 ((ull & 0x0000000000ff0000) << 24) | \ 67 ((ull & 0x000000000000ff00) << 40) | \ 68 ((ull & 0x00000000000000ff) << 56) 69 70 #else /* A recent Visual studio compiler or not VC */ 71 72 /* 73 * Swap byte ordering of unsigned long long timestamp on a big endian 74 * machine. 75 */ 76 #define SWAPLL(ull) ((ull & 0xff00000000000000LL) >> 56) | \ 77 ((ull & 0x00ff000000000000LL) >> 40) | \ 78 ((ull & 0x0000ff0000000000LL) >> 24) | \ 79 ((ull & 0x000000ff00000000LL) >> 8) | \ 80 ((ull & 0x00000000ff000000LL) << 8) | \ 81 ((ull & 0x0000000000ff0000LL) << 24) | \ 82 ((ull & 0x000000000000ff00LL) << 40) | \ 83 ((ull & 0x00000000000000ffLL) << 56) 84 85 #endif /* _MSC_VER */ 86 87 /* 88 * Maximum snapshot length. 89 * 90 * Somewhat arbitrary, but chosen to be: 91 * 92 * 1) big enough for maximum-size Linux loopback packets (65549) 93 * and some USB packets captured with USBPcap: 94 * 95 * http://desowin.org/usbpcap/ 96 * 97 * (> 131072, < 262144) 98 * 99 * and 100 * 101 * 2) small enough not to cause attempts to allocate huge amounts of 102 * memory; some applications might use the snapshot length in a 103 * savefile header to control the size of the buffer they allocate, 104 * so a size of, say, 2^31-1 might not work well. 105 * 106 * We don't enforce this in pcap_set_snaplen(), but we use it internally. 107 */ 108 #define MAXIMUM_SNAPLEN 262144 109 110 struct pcap_opt { 111 char *device; 112 int timeout; /* timeout for buffering */ 113 u_int buffer_size; 114 int promisc; 115 int rfmon; /* monitor mode */ 116 int immediate; /* immediate mode - deliver packets as soon as they arrive */ 117 int tstamp_type; 118 int tstamp_precision; 119 }; 120 121 typedef int (*activate_op_t)(pcap_t *); 122 typedef int (*can_set_rfmon_op_t)(pcap_t *); 123 typedef int (*read_op_t)(pcap_t *, int cnt, pcap_handler, u_char *); 124 typedef int (*inject_op_t)(pcap_t *, const void *, size_t); 125 typedef int (*setfilter_op_t)(pcap_t *, struct bpf_program *); 126 typedef int (*setdirection_op_t)(pcap_t *, pcap_direction_t); 127 typedef int (*set_datalink_op_t)(pcap_t *, int); 128 typedef int (*getnonblock_op_t)(pcap_t *, char *); 129 typedef int (*setnonblock_op_t)(pcap_t *, int, char *); 130 typedef int (*stats_op_t)(pcap_t *, struct pcap_stat *); 131 #ifdef _WIN32 132 typedef struct pcap_stat *(*stats_ex_op_t)(pcap_t *, int *); 133 typedef int (*setbuff_op_t)(pcap_t *, int); 134 typedef int (*setmode_op_t)(pcap_t *, int); 135 typedef int (*setmintocopy_op_t)(pcap_t *, int); 136 typedef HANDLE (*getevent_op_t)(pcap_t *); 137 typedef int (*oid_get_request_op_t)(pcap_t *, bpf_u_int32, void *, size_t *); 138 typedef int (*oid_set_request_op_t)(pcap_t *, bpf_u_int32, const void *, size_t *); 139 typedef u_int (*sendqueue_transmit_op_t)(pcap_t *, pcap_send_queue *, int); 140 typedef int (*setuserbuffer_op_t)(pcap_t *, int); 141 typedef int (*live_dump_op_t)(pcap_t *, char *, int, int); 142 typedef int (*live_dump_ended_op_t)(pcap_t *, int); 143 typedef PAirpcapHandle (*get_airpcap_handle_op_t)(pcap_t *); 144 #endif 145 typedef void (*cleanup_op_t)(pcap_t *); 146 147 /* 148 * We put all the stuff used in the read code path at the beginning, 149 * to try to keep it together in the same cache line or lines. 150 */ 151 struct pcap { 152 /* 153 * Method to call to read packets on a live capture. 154 */ 155 read_op_t read_op; 156 157 /* 158 * Method to call to read packets from a savefile. 159 */ 160 int (*next_packet_op)(pcap_t *, struct pcap_pkthdr *, u_char **); 161 162 #ifdef _WIN32 163 ADAPTER *adapter; 164 #else 165 int fd; 166 int selectable_fd; 167 #endif /* _WIN32 */ 168 169 /* 170 * Read buffer. 171 */ 172 u_int bufsize; 173 void *buffer; 174 u_char *bp; 175 int cc; 176 177 int break_loop; /* flag set to force break from packet-reading loop */ 178 179 void *priv; /* private data for methods */ 180 181 int swapped; 182 FILE *rfile; /* null if live capture, non-null if savefile */ 183 u_int fddipad; 184 struct pcap *next; /* list of open pcaps that need stuff cleared on close */ 185 186 /* 187 * File version number; meaningful only for a savefile, but we 188 * keep it here so that apps that (mistakenly) ask for the 189 * version numbers will get the same zero values that they 190 * always did. 191 */ 192 int version_major; 193 int version_minor; 194 195 int snapshot; 196 int linktype; /* Network linktype */ 197 int linktype_ext; /* Extended information stored in the linktype field of a file */ 198 int tzoff; /* timezone offset */ 199 int offset; /* offset for proper alignment */ 200 int activated; /* true if the capture is really started */ 201 int oldstyle; /* if we're opening with pcap_open_live() */ 202 203 struct pcap_opt opt; 204 205 /* 206 * Place holder for pcap_next(). 207 */ 208 u_char *pkt; 209 210 #ifdef _WIN32 211 struct pcap_stat stat; /* used for pcap_stats_ex() */ 212 #endif 213 214 /* We're accepting only packets in this direction/these directions. */ 215 pcap_direction_t direction; 216 217 /* 218 * Flags to affect BPF code generation. 219 */ 220 int bpf_codegen_flags; 221 222 /* 223 * Placeholder for filter code if bpf not in kernel. 224 */ 225 struct bpf_program fcode; 226 227 char errbuf[PCAP_ERRBUF_SIZE + 1]; 228 int dlt_count; 229 u_int *dlt_list; 230 int tstamp_type_count; 231 u_int *tstamp_type_list; 232 int tstamp_precision_count; 233 u_int *tstamp_precision_list; 234 235 struct pcap_pkthdr pcap_header; /* This is needed for the pcap_next_ex() to work */ 236 237 /* 238 * More methods. 239 */ 240 activate_op_t activate_op; 241 can_set_rfmon_op_t can_set_rfmon_op; 242 inject_op_t inject_op; 243 setfilter_op_t setfilter_op; 244 setdirection_op_t setdirection_op; 245 set_datalink_op_t set_datalink_op; 246 getnonblock_op_t getnonblock_op; 247 setnonblock_op_t setnonblock_op; 248 stats_op_t stats_op; 249 250 /* 251 * Routine to use as callback for pcap_next()/pcap_next_ex(). 252 */ 253 pcap_handler oneshot_callback; 254 255 #ifdef _WIN32 256 /* 257 * These are, at least currently, specific to the Win32 NPF 258 * driver. 259 */ 260 stats_ex_op_t stats_ex_op; 261 setbuff_op_t setbuff_op; 262 setmode_op_t setmode_op; 263 setmintocopy_op_t setmintocopy_op; 264 getevent_op_t getevent_op; 265 oid_get_request_op_t oid_get_request_op; 266 oid_set_request_op_t oid_set_request_op; 267 sendqueue_transmit_op_t sendqueue_transmit_op; 268 setuserbuffer_op_t setuserbuffer_op; 269 live_dump_op_t live_dump_op; 270 live_dump_ended_op_t live_dump_ended_op; 271 get_airpcap_handle_op_t get_airpcap_handle_op; 272 #endif 273 cleanup_op_t cleanup_op; 274 }; 275 276 /* 277 * BPF code generation flags. 278 */ 279 #define BPF_SPECIAL_VLAN_HANDLING 0x00000001 /* special VLAN handling for Linux */ 280 281 /* 282 * This is a timeval as stored in a savefile. 283 * It has to use the same types everywhere, independent of the actual 284 * `struct timeval'; `struct timeval' has 32-bit tv_sec values on some 285 * platforms and 64-bit tv_sec values on other platforms, and writing 286 * out native `struct timeval' values would mean files could only be 287 * read on systems with the same tv_sec size as the system on which 288 * the file was written. 289 */ 290 291 struct pcap_timeval { 292 bpf_int32 tv_sec; /* seconds */ 293 bpf_int32 tv_usec; /* microseconds */ 294 }; 295 296 /* 297 * This is a `pcap_pkthdr' as actually stored in a savefile. 298 * 299 * Do not change the format of this structure, in any way (this includes 300 * changes that only affect the length of fields in this structure), 301 * and do not make the time stamp anything other than seconds and 302 * microseconds (e.g., seconds and nanoseconds). Instead: 303 * 304 * introduce a new structure for the new format; 305 * 306 * send mail to "tcpdump-workers (at) lists.tcpdump.org", requesting 307 * a new magic number for your new capture file format, and, when 308 * you get the new magic number, put it in "savefile.c"; 309 * 310 * use that magic number for save files with the changed record 311 * header; 312 * 313 * make the code in "savefile.c" capable of reading files with 314 * the old record header as well as files with the new record header 315 * (using the magic number to determine the header format). 316 * 317 * Then supply the changes by forking the branch at 318 * 319 * https://github.com/the-tcpdump-group/libpcap/issues 320 * 321 * and issuing a pull request, so that future versions of libpcap and 322 * programs that use it (such as tcpdump) will be able to read your new 323 * capture file format. 324 */ 325 326 struct pcap_sf_pkthdr { 327 struct pcap_timeval ts; /* time stamp */ 328 bpf_u_int32 caplen; /* length of portion present */ 329 bpf_u_int32 len; /* length this packet (off wire) */ 330 }; 331 332 /* 333 * How a `pcap_pkthdr' is actually stored in savefiles written 334 * by some patched versions of libpcap (e.g. the ones in Red 335 * Hat Linux 6.1 and 6.2). 336 * 337 * Do not change the format of this structure, in any way (this includes 338 * changes that only affect the length of fields in this structure). 339 * Instead, introduce a new structure, as per the above. 340 */ 341 342 struct pcap_sf_patched_pkthdr { 343 struct pcap_timeval ts; /* time stamp */ 344 bpf_u_int32 caplen; /* length of portion present */ 345 bpf_u_int32 len; /* length this packet (off wire) */ 346 int index; 347 unsigned short protocol; 348 unsigned char pkt_type; 349 }; 350 351 /* 352 * User data structure for the one-shot callback used for pcap_next() 353 * and pcap_next_ex(). 354 */ 355 struct oneshot_userdata { 356 struct pcap_pkthdr *hdr; 357 const u_char **pkt; 358 pcap_t *pd; 359 }; 360 361 #ifndef min 362 #define min(a, b) ((a) > (b) ? (b) : (a)) 363 #endif 364 365 int pcap_offline_read(pcap_t *, int, pcap_handler, u_char *); 366 367 #include <stdarg.h> 368 369 #include "portability.h" 370 371 /* 372 * Does the packet count argument to a module's read routine say 373 * "supply packets until you run out of packets"? 374 */ 375 #define PACKET_COUNT_IS_UNLIMITED(count) ((count) <= 0) 376 377 /* 378 * Routines that most pcap implementations can use for non-blocking mode. 379 */ 380 #if !defined(_WIN32) && !defined(MSDOS) 381 int pcap_getnonblock_fd(pcap_t *, char *); 382 int pcap_setnonblock_fd(pcap_t *p, int, char *); 383 #endif 384 385 /* 386 * Internal interfaces for "pcap_create()". 387 * 388 * "pcap_create_interface()" is the routine to do a pcap_create on 389 * a regular network interface. There are multiple implementations 390 * of this, one for each platform type (Linux, BPF, DLPI, etc.), 391 * with the one used chosen by the configure script. 392 * 393 * "pcap_create_common()" allocates and fills in a pcap_t, for use 394 * by pcap_create routines. 395 */ 396 pcap_t *pcap_create_interface(const char *, char *); 397 pcap_t *pcap_create_common(char *, size_t); 398 int pcap_do_addexit(pcap_t *); 399 void pcap_add_to_pcaps_to_close(pcap_t *); 400 void pcap_remove_from_pcaps_to_close(pcap_t *); 401 void pcap_cleanup_live_common(pcap_t *); 402 int pcap_check_activated(pcap_t *); 403 404 /* 405 * Internal interfaces for "pcap_findalldevs()". 406 * 407 * "pcap_platform_finddevs()" is a platform-dependent routine to 408 * find local network interfaces. 409 * 410 * "pcap_findalldevs_interfaces()" is a helper to find those interfaces 411 * using the "standard" mechanisms (SIOCGIFCONF, "getifaddrs()", etc.). 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_platform_finddevs(pcap_if_t **, char *); 417 #if !defined(_WIN32) && !defined(MSDOS) 418 int pcap_findalldevs_interfaces(pcap_if_t **, char *, 419 int (*)(const char *)); 420 #endif 421 int add_addr_to_iflist(pcap_if_t **, const char *, bpf_u_int32, 422 struct sockaddr *, size_t, struct sockaddr *, size_t, 423 struct sockaddr *, size_t, struct sockaddr *, size_t, char *); 424 int add_addr_to_dev(pcap_if_t *, struct sockaddr *, size_t, 425 struct sockaddr *, size_t, struct sockaddr *, size_t, 426 struct sockaddr *dstaddr, size_t, char *errbuf); 427 int pcap_add_if(pcap_if_t **, const char *, bpf_u_int32, const char *, 428 char *); 429 int add_or_find_if(pcap_if_t **, pcap_if_t **, const char *, bpf_u_int32, 430 const char *, char *); 431 #ifndef _WIN32 432 bpf_u_int32 if_flags_to_pcap_flags(const char *, u_int); 433 #endif 434 435 /* 436 * Internal interfaces for "pcap_open_offline()". 437 * 438 * "pcap_open_offline_common()" allocates and fills in a pcap_t, for use 439 * by pcap_open_offline routines. 440 * 441 * "sf_cleanup()" closes the file handle associated with a pcap_t, if 442 * appropriate, and frees all data common to all modules for handling 443 * savefile types. 444 */ 445 pcap_t *pcap_open_offline_common(char *ebuf, size_t size); 446 void sf_cleanup(pcap_t *p); 447 448 /* 449 * Internal interfaces for both "pcap_create()" and routines that 450 * open savefiles. 451 * 452 * "pcap_oneshot()" is the standard one-shot callback for "pcap_next()" 453 * and "pcap_next_ex()". 454 */ 455 void pcap_oneshot(u_char *, const struct pcap_pkthdr *, const u_char *); 456 457 #ifdef _WIN32 458 void pcap_win32_err_to_str(DWORD, char *); 459 #endif 460 461 int install_bpf_program(pcap_t *, struct bpf_program *); 462 463 int pcap_strcasecmp(const char *, const char *); 464 465 #ifdef __cplusplus 466 } 467 #endif 468 469 #endif 470
