1 /* $NetBSD: pcap-int.h,v 1.3 2015/03/31 21:39:42 christos Exp $ */ 2 3 /* 4 * Copyright (c) 1994, 1995, 1996 5 * The Regents of the University of California. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. All advertising materials mentioning features or use of this software 16 * must display the following acknowledgement: 17 * This product includes software developed by the Computer Systems 18 * Engineering Group at Lawrence Berkeley Laboratory. 19 * 4. Neither the name of the University nor of the Laboratory may be used 20 * to endorse or promote products derived from this software without 21 * specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 */ 35 36 #ifndef pcap_int_h 37 #define pcap_int_h 38 39 #include <pcap/pcap.h> 40 41 #ifdef __cplusplus 42 extern "C" { 43 #endif 44 45 #ifdef WIN32 46 #include <Packet32.h> 47 extern CRITICAL_SECTION g_PcapCompileCriticalSection; 48 #endif /* WIN32 */ 49 50 #ifdef 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 *source; 112 int timeout; /* timeout for buffering */ 113 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 int (*setbuff_op_t)(pcap_t *, int); 133 typedef int (*setmode_op_t)(pcap_t *, int); 134 typedef int (*setmintocopy_op_t)(pcap_t *, int); 135 typedef Adapter *(*getadapter_op_t)(pcap_t *); 136 #endif 137 typedef void (*cleanup_op_t)(pcap_t *); 138 139 /* 140 * We put all the stuff used in the read code path at the beginning, 141 * to try to keep it together in the same cache line or lines. 142 */ 143 struct pcap { 144 /* 145 * Method to call to read packets on a live capture. 146 */ 147 read_op_t read_op; 148 149 /* 150 * Method to call to read to read packets from a savefile. 151 */ 152 int (*next_packet_op)(pcap_t *, struct pcap_pkthdr *, u_char **); 153 154 #ifdef WIN32 155 ADAPTER *adapter; 156 LPPACKET Packet; 157 int nonblock; 158 #else 159 int fd; 160 int selectable_fd; 161 #endif /* WIN32 */ 162 163 /* 164 * Read buffer. 165 */ 166 int bufsize; 167 u_char *buffer; 168 u_char *bp; 169 int cc; 170 171 int break_loop; /* flag set to force break from packet-reading loop */ 172 173 void *priv; /* private data for methods */ 174 175 int swapped; 176 FILE *rfile; /* null if live capture, non-null if savefile */ 177 int fddipad; 178 struct pcap *next; /* list of open pcaps that need stuff cleared on close */ 179 180 /* 181 * File version number; meaningful only for a savefile, but we 182 * keep it here so that apps that (mistakenly) ask for the 183 * version numbers will get the same zero values that they 184 * always did. 185 */ 186 int version_major; 187 int version_minor; 188 189 int snapshot; 190 int linktype; /* Network linktype */ 191 int linktype_ext; /* Extended information stored in the linktype field of a file */ 192 int tzoff; /* timezone offset */ 193 int offset; /* offset for proper alignment */ 194 int activated; /* true if the capture is really started */ 195 int oldstyle; /* if we're opening with pcap_open_live() */ 196 197 struct pcap_opt opt; 198 199 /* 200 * Place holder for pcap_next(). 201 */ 202 u_char *pkt; 203 204 /* We're accepting only packets in this direction/these directions. */ 205 pcap_direction_t direction; 206 207 /* 208 * Flags to affect BPF code generation. 209 */ 210 int bpf_codegen_flags; 211 212 /* 213 * Placeholder for filter code if bpf not in kernel. 214 */ 215 struct bpf_program fcode; 216 217 char errbuf[PCAP_ERRBUF_SIZE + 1]; 218 int dlt_count; 219 u_int *dlt_list; 220 int tstamp_type_count; 221 u_int *tstamp_type_list; 222 int tstamp_precision_count; 223 u_int *tstamp_precision_list; 224 225 struct pcap_pkthdr pcap_header; /* This is needed for the pcap_next_ex() to work */ 226 227 /* 228 * More methods. 229 */ 230 activate_op_t activate_op; 231 can_set_rfmon_op_t can_set_rfmon_op; 232 inject_op_t inject_op; 233 setfilter_op_t setfilter_op; 234 setdirection_op_t setdirection_op; 235 set_datalink_op_t set_datalink_op; 236 getnonblock_op_t getnonblock_op; 237 setnonblock_op_t setnonblock_op; 238 stats_op_t stats_op; 239 240 /* 241 * Routine to use as callback for pcap_next()/pcap_next_ex(). 242 */ 243 pcap_handler oneshot_callback; 244 245 #ifdef WIN32 246 /* 247 * These are, at least currently, specific to the Win32 NPF 248 * driver. 249 */ 250 setbuff_op_t setbuff_op; 251 setmode_op_t setmode_op; 252 setmintocopy_op_t setmintocopy_op; 253 getadapter_op_t getadapter_op; 254 #endif 255 cleanup_op_t cleanup_op; 256 }; 257 258 /* 259 * BPF code generation flags. 260 */ 261 #define BPF_SPECIAL_VLAN_HANDLING 0x00000001 /* special VLAN handling for Linux */ 262 263 /* 264 * This is a timeval as stored in a savefile. 265 * It has to use the same types everywhere, independent of the actual 266 * `struct timeval'; `struct timeval' has 32-bit tv_sec values on some 267 * platforms and 64-bit tv_sec values on other platforms, and writing 268 * out native `struct timeval' values would mean files could only be 269 * read on systems with the same tv_sec size as the system on which 270 * the file was written. 271 */ 272 273 struct pcap_timeval { 274 bpf_int32 tv_sec; /* seconds */ 275 bpf_int32 tv_usec; /* microseconds */ 276 }; 277 278 /* 279 * This is a `pcap_pkthdr' as actually stored in a savefile. 280 * 281 * Do not change the format of this structure, in any way (this includes 282 * changes that only affect the length of fields in this structure), 283 * and do not make the time stamp anything other than seconds and 284 * microseconds (e.g., seconds and nanoseconds). Instead: 285 * 286 * introduce a new structure for the new format; 287 * 288 * send mail to "tcpdump-workers@lists.tcpdump.org", requesting 289 * a new magic number for your new capture file format, and, when 290 * you get the new magic number, put it in "savefile.c"; 291 * 292 * use that magic number for save files with the changed record 293 * header; 294 * 295 * make the code in "savefile.c" capable of reading files with 296 * the old record header as well as files with the new record header 297 * (using the magic number to determine the header format). 298 * 299 * Then supply the changes by forking the branch at 300 * 301 * https://github.com/the-tcpdump-group/libpcap/issues 302 * 303 * and issuing a pull request, so that future versions of libpcap and 304 * programs that use it (such as tcpdump) will be able to read your new 305 * capture file format. 306 */ 307 308 struct pcap_sf_pkthdr { 309 struct pcap_timeval ts; /* time stamp */ 310 bpf_u_int32 caplen; /* length of portion present */ 311 bpf_u_int32 len; /* length this packet (off wire) */ 312 }; 313 314 /* 315 * How a `pcap_pkthdr' is actually stored in savefiles written 316 * by some patched versions of libpcap (e.g. the ones in Red 317 * Hat Linux 6.1 and 6.2). 318 * 319 * Do not change the format of this structure, in any way (this includes 320 * changes that only affect the length of fields in this structure). 321 * Instead, introduce a new structure, as per the above. 322 */ 323 324 struct pcap_sf_patched_pkthdr { 325 struct pcap_timeval ts; /* time stamp */ 326 bpf_u_int32 caplen; /* length of portion present */ 327 bpf_u_int32 len; /* length this packet (off wire) */ 328 int index; 329 unsigned short protocol; 330 unsigned char pkt_type; 331 }; 332 333 /* 334 * User data structure for the one-shot callback used for pcap_next() 335 * and pcap_next_ex(). 336 */ 337 struct oneshot_userdata { 338 struct pcap_pkthdr *hdr; 339 const u_char **pkt; 340 pcap_t *pd; 341 }; 342 343 int yylex(void); 344 345 #ifndef min 346 #define min(a, b) ((a) > (b) ? (b) : (a)) 347 #endif 348 349 /* XXX should these be in pcap.h? */ 350 int pcap_offline_read(pcap_t *, int, pcap_handler, u_char *); 351 int pcap_read(pcap_t *, int cnt, pcap_handler, u_char *); 352 353 #ifndef HAVE_STRLCPY 354 #define strlcpy(x, y, z) \ 355 (strncpy((x), (y), (z)), \ 356 ((z) <= 0 ? 0 : ((x)[(z) - 1] = '\0')), \ 357 strlen((y))) 358 #endif 359 360 #include <stdarg.h> 361 362 #if !defined(HAVE_SNPRINTF) 363 #define snprintf pcap_snprintf 364 extern int snprintf (char *, size_t, const char *, ...); 365 #endif 366 367 #if !defined(HAVE_VSNPRINTF) 368 #define vsnprintf pcap_vsnprintf 369 extern int vsnprintf (char *, size_t, const char *, va_list ap); 370 #endif 371 372 /* 373 * Does the packet count argument to a module's read routine say 374 * "supply packets until you run out of packets"? 375 */ 376 #define PACKET_COUNT_IS_UNLIMITED(count) ((count) <= 0) 377 378 /* 379 * Routines that most pcap implementations can use for non-blocking mode. 380 */ 381 #if !defined(WIN32) && !defined(MSDOS) 382 int pcap_getnonblock_fd(pcap_t *, char *); 383 int pcap_setnonblock_fd(pcap_t *p, int, char *); 384 #endif 385 386 /* 387 * Internal interfaces for "pcap_create()". 388 * 389 * "pcap_create_interface()" is the routine to do a pcap_create on 390 * a regular network interface. There are multiple implementations 391 * of this, one for each platform type (Linux, BPF, DLPI, etc.), 392 * with the one used chosen by the configure script. 393 * 394 * "pcap_create_common()" allocates and fills in a pcap_t, for use 395 * by pcap_create routines. 396 */ 397 pcap_t *pcap_create_interface(const char *, char *); 398 pcap_t *pcap_create_common(const char *, char *, size_t); 399 int pcap_do_addexit(pcap_t *); 400 void pcap_add_to_pcaps_to_close(pcap_t *); 401 void pcap_remove_from_pcaps_to_close(pcap_t *); 402 void pcap_cleanup_live_common(pcap_t *); 403 int pcap_not_initialized(pcap_t *); 404 int pcap_check_activated(pcap_t *); 405 406 /* 407 * Internal interfaces for "pcap_findalldevs()". 408 * 409 * "pcap_findalldevs_interfaces()" finds interfaces using the 410 * "standard" mechanisms (SIOCGIFCONF, "getifaddrs()", etc.). 411 * 412 * "pcap_platform_finddevs()" is a platform-dependent routine to 413 * add devices not found by the "standard" mechanisms. 414 * 415 * "pcap_add_if()" adds an interface to the list of interfaces, for 416 * use by various "find interfaces" routines. 417 */ 418 int pcap_findalldevs_interfaces(pcap_if_t **, char *); 419 int pcap_platform_finddevs(pcap_if_t **, char *); 420 int add_addr_to_iflist(pcap_if_t **, const char *, u_int, struct sockaddr *, 421 size_t, struct sockaddr *, size_t, struct sockaddr *, size_t, 422 struct sockaddr *, size_t, char *); 423 int add_addr_to_dev(pcap_if_t *, struct sockaddr *, size_t, 424 struct sockaddr *, size_t, struct sockaddr *, size_t, 425 struct sockaddr *dstaddr, size_t, char *errbuf); 426 int pcap_add_if(pcap_if_t **, const char *, u_int, const char *, char *); 427 struct sockaddr *dup_sockaddr(struct sockaddr *, size_t); 428 int add_or_find_if(pcap_if_t **, pcap_if_t **, const char *, u_int, 429 const char *, char *); 430 431 /* 432 * Internal interfaces for "pcap_open_offline()". 433 * 434 * "pcap_open_offline_common()" allocates and fills in a pcap_t, for use 435 * by pcap_open_offline routines. 436 * 437 * "sf_cleanup()" closes the file handle associated with a pcap_t, if 438 * appropriate, and frees all data common to all modules for handling 439 * savefile types. 440 */ 441 pcap_t *pcap_open_offline_common(char *ebuf, size_t size); 442 void sf_cleanup(pcap_t *p); 443 444 /* 445 * Internal interfaces for both "pcap_create()" and routines that 446 * open savefiles. 447 * 448 * "pcap_oneshot()" is the standard one-shot callback for "pcap_next()" 449 * and "pcap_next_ex()". 450 */ 451 void pcap_oneshot(u_char *, const struct pcap_pkthdr *, const u_char *); 452 453 #ifdef WIN32 454 char *pcap_win32strerror(void); 455 #endif 456 457 int install_bpf_program(pcap_t *, struct bpf_program *); 458 459 int pcap_strcasecmp(const char *, const char *); 460 461 #ifdef __cplusplus 462 } 463 #endif 464 465 #endif 466