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  * @(#) $Header: /tcpdump/master/libpcap/pcap-int.h,v 1.94 2008-09-16 00:20:23 guy Exp $ (LBL)
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 struct pcap_opt {
88 	char	*source;
89 	int	timeout;	/* timeout for buffering */
90 	int	buffer_size;
91 	int	promisc;
92 	int	rfmon;		/* monitor mode */
93 	int	immediate;	/* immediate mode - deliver packets as soon as they arrive */
94 	int	tstamp_type;
95 	int	tstamp_precision;
96 };
97 
98 typedef int	(*activate_op_t)(pcap_t *);
99 typedef int	(*can_set_rfmon_op_t)(pcap_t *);
100 typedef int	(*read_op_t)(pcap_t *, int cnt, pcap_handler, u_char *);
101 typedef int	(*inject_op_t)(pcap_t *, const void *, size_t);
102 typedef int	(*setfilter_op_t)(pcap_t *, struct bpf_program *);
103 typedef int	(*setdirection_op_t)(pcap_t *, pcap_direction_t);
104 typedef int	(*set_datalink_op_t)(pcap_t *, int);
105 typedef int	(*getnonblock_op_t)(pcap_t *, char *);
106 typedef int	(*setnonblock_op_t)(pcap_t *, int, char *);
107 typedef int	(*stats_op_t)(pcap_t *, struct pcap_stat *);
108 #ifdef WIN32
109 typedef int	(*setbuff_op_t)(pcap_t *, int);
110 typedef int	(*setmode_op_t)(pcap_t *, int);
111 typedef int	(*setmintocopy_op_t)(pcap_t *, int);
112 typedef Adapter *(*getadapter_op_t)(pcap_t *);
113 #endif
114 typedef void	(*cleanup_op_t)(pcap_t *);
115 
116 /*
117  * We put all the stuff used in the read code path at the beginning,
118  * to try to keep it together in the same cache line or lines.
119  */
120 struct pcap {
121 	/*
122 	 * Method to call to read packets on a live capture.
123 	 */
124 	read_op_t read_op;
125 
126 	/*
127 	 * Method to call to read to read packets from a savefile.
128 	 */
129 	int (*next_packet_op)(pcap_t *, struct pcap_pkthdr *, u_char **);
130 
131 #ifdef WIN32
132 	ADAPTER *adapter;
133 	LPPACKET Packet;
134 	int nonblock;
135 #else
136 	int fd;
137 	int selectable_fd;
138 #endif /* WIN32 */
139 
140 	/*
141 	 * Read buffer.
142 	 */
143 	int bufsize;
144 	u_char *buffer;
145 	u_char *bp;
146 	int cc;
147 
148 	int break_loop;		/* flag set to force break from packet-reading loop */
149 
150 	void *priv;		/* private data for methods */
151 
152 	int swapped;
153 	FILE *rfile;		/* null if live capture, non-null if savefile */
154 	int fddipad;
155 	struct pcap *next;	/* list of open pcaps that need stuff cleared on close */
156 
157 	/*
158 	 * File version number; meaningful only for a savefile, but we
159 	 * keep it here so that apps that (mistakenly) ask for the
160 	 * version numbers will get the same zero values that they
161 	 * always did.
162 	 */
163 	int version_major;
164 	int version_minor;
165 
166 	int snapshot;
167 	int linktype;		/* Network linktype */
168 	int linktype_ext;       /* Extended information stored in the linktype field of a file */
169 	int tzoff;		/* timezone offset */
170 	int offset;		/* offset for proper alignment */
171 	int activated;		/* true if the capture is really started */
172 	int oldstyle;		/* if we're opening with pcap_open_live() */
173 
174 	struct pcap_opt opt;
175 
176 	/*
177 	 * Place holder for pcap_next().
178 	 */
179 	u_char *pkt;
180 
181 	/* We're accepting only packets in this direction/these directions. */
182 	pcap_direction_t direction;
183 
184 	/*
185 	 * Placeholder for filter code if bpf not in kernel.
186 	 */
187 	struct bpf_program fcode;
188 
189 	char errbuf[PCAP_ERRBUF_SIZE + 1];
190 	int dlt_count;
191 	u_int *dlt_list;
192 	int tstamp_type_count;
193 	u_int *tstamp_type_list;
194 	int tstamp_precision_count;
195 	u_int *tstamp_precision_list;
196 
197 	struct pcap_pkthdr pcap_header;	/* This is needed for the pcap_next_ex() to work */
198 
199 	/*
200 	 * More methods.
201 	 */
202 	activate_op_t activate_op;
203 	can_set_rfmon_op_t can_set_rfmon_op;
204 	inject_op_t inject_op;
205 	setfilter_op_t setfilter_op;
206 	setdirection_op_t setdirection_op;
207 	set_datalink_op_t set_datalink_op;
208 	getnonblock_op_t getnonblock_op;
209 	setnonblock_op_t setnonblock_op;
210 	stats_op_t stats_op;
211 
212 	/*
213 	 * Routine to use as callback for pcap_next()/pcap_next_ex().
214 	 */
215 	pcap_handler oneshot_callback;
216 
217 #ifdef WIN32
218 	/*
219 	 * These are, at least currently, specific to the Win32 NPF
220 	 * driver.
221 	 */
222 	setbuff_op_t setbuff_op;
223 	setmode_op_t setmode_op;
224 	setmintocopy_op_t setmintocopy_op;
225 	getadapter_op_t getadapter_op;
226 #endif
227 	cleanup_op_t cleanup_op;
228 };
229 
230 /*
231  * This is a timeval as stored in a savefile.
232  * It has to use the same types everywhere, independent of the actual
233  * `struct timeval'; `struct timeval' has 32-bit tv_sec values on some
234  * platforms and 64-bit tv_sec values on other platforms, and writing
235  * out native `struct timeval' values would mean files could only be
236  * read on systems with the same tv_sec size as the system on which
237  * the file was written.
238  */
239 
240 struct pcap_timeval {
241     bpf_int32 tv_sec;		/* seconds */
242     bpf_int32 tv_usec;		/* microseconds */
243 };
244 
245 /*
246  * This is a `pcap_pkthdr' as actually stored in a savefile.
247  *
248  * Do not change the format of this structure, in any way (this includes
249  * changes that only affect the length of fields in this structure),
250  * and do not make the time stamp anything other than seconds and
251  * microseconds (e.g., seconds and nanoseconds).  Instead:
252  *
253  *	introduce a new structure for the new format;
254  *
255  *	send mail to "tcpdump-workers@lists.tcpdump.org", requesting
256  *	a new magic number for your new capture file format, and, when
257  *	you get the new magic number, put it in "savefile.c";
258  *
259  *	use that magic number for save files with the changed record
260  *	header;
261  *
262  *	make the code in "savefile.c" capable of reading files with
263  *	the old record header as well as files with the new record header
264  *	(using the magic number to determine the header format).
265  *
266  * Then supply the changes by forking the branch at
267  *
268  *	https://github.com/the-tcpdump-group/libpcap/issues
269  *
270  * and issuing a pull request, so that future versions of libpcap and
271  * programs that use it (such as tcpdump) will be able to read your new
272  * capture file format.
273  */
274 
275 struct pcap_sf_pkthdr {
276     struct pcap_timeval ts;	/* time stamp */
277     bpf_u_int32 caplen;		/* length of portion present */
278     bpf_u_int32 len;		/* length this packet (off wire) */
279 };
280 
281 /*
282  * How a `pcap_pkthdr' is actually stored in savefiles written
283  * by some patched versions of libpcap (e.g. the ones in Red
284  * Hat Linux 6.1 and 6.2).
285  *
286  * Do not change the format of this structure, in any way (this includes
287  * changes that only affect the length of fields in this structure).
288  * Instead, introduce a new structure, as per the above.
289  */
290 
291 struct pcap_sf_patched_pkthdr {
292     struct pcap_timeval ts;	/* time stamp */
293     bpf_u_int32 caplen;		/* length of portion present */
294     bpf_u_int32 len;		/* length this packet (off wire) */
295     int		index;
296     unsigned short protocol;
297     unsigned char pkt_type;
298 };
299 
300 /*
301  * User data structure for the one-shot callback used for pcap_next()
302  * and pcap_next_ex().
303  */
304 struct oneshot_userdata {
305 	struct pcap_pkthdr *hdr;
306 	const u_char **pkt;
307 	pcap_t *pd;
308 };
309 
310 int	yylex(void);
311 
312 #ifndef min
313 #define min(a, b) ((a) > (b) ? (b) : (a))
314 #endif
315 
316 /* XXX should these be in pcap.h? */
317 int	pcap_offline_read(pcap_t *, int, pcap_handler, u_char *);
318 int	pcap_read(pcap_t *, int cnt, pcap_handler, u_char *);
319 
320 #ifndef HAVE_STRLCPY
321 #define strlcpy(x, y, z) \
322 	(strncpy((x), (y), (z)), \
323 	 ((z) <= 0 ? 0 : ((x)[(z) - 1] = '\0')), \
324 	 strlen((y)))
325 #endif
326 
327 #include <stdarg.h>
328 
329 #if !defined(HAVE_SNPRINTF)
330 #define snprintf pcap_snprintf
331 extern int snprintf (char *, size_t, const char *, ...);
332 #endif
333 
334 #if !defined(HAVE_VSNPRINTF)
335 #define vsnprintf pcap_vsnprintf
336 extern int vsnprintf (char *, size_t, const char *, va_list ap);
337 #endif
338 
339 /*
340  * Does the packet count argument to a module's read routine say
341  * "supply packets until you run out of packets"?
342  */
343 #define PACKET_COUNT_IS_UNLIMITED(count)	((count) <= 0)
344 
345 /*
346  * Routines that most pcap implementations can use for non-blocking mode.
347  */
348 #if !defined(WIN32) && !defined(MSDOS)
349 int	pcap_getnonblock_fd(pcap_t *, char *);
350 int	pcap_setnonblock_fd(pcap_t *p, int, char *);
351 #endif
352 
353 /*
354  * Internal interfaces for "pcap_create()".
355  *
356  * "pcap_create_interface()" is the routine to do a pcap_create on
357  * a regular network interface.  There are multiple implementations
358  * of this, one for each platform type (Linux, BPF, DLPI, etc.),
359  * with the one used chosen by the configure script.
360  *
361  * "pcap_create_common()" allocates and fills in a pcap_t, for use
362  * by pcap_create routines.
363  */
364 pcap_t	*pcap_create_interface(const char *, char *);
365 pcap_t	*pcap_create_common(const char *, char *, size_t);
366 int	pcap_do_addexit(pcap_t *);
367 void	pcap_add_to_pcaps_to_close(pcap_t *);
368 void	pcap_remove_from_pcaps_to_close(pcap_t *);
369 void	pcap_cleanup_live_common(pcap_t *);
370 int	pcap_not_initialized(pcap_t *);
371 int	pcap_check_activated(pcap_t *);
372 
373 /*
374  * Internal interfaces for "pcap_findalldevs()".
375  *
376  * "pcap_findalldevs_interfaces()" finds interfaces using the
377  * "standard" mechanisms (SIOCGIFCONF, "getifaddrs()", etc.).
378  *
379  * "pcap_platform_finddevs()" is a platform-dependent routine to
380  * add devices not found by the "standard" mechanisms.
381  *
382  * "pcap_add_if()" adds an interface to the list of interfaces, for
383  * use by various "find interfaces" routines.
384  */
385 int	pcap_findalldevs_interfaces(pcap_if_t **, char *);
386 int	pcap_platform_finddevs(pcap_if_t **, char *);
387 int	add_addr_to_iflist(pcap_if_t **, const char *, u_int, struct sockaddr *,
388 	    size_t, struct sockaddr *, size_t, struct sockaddr *, size_t,
389 	    struct sockaddr *, size_t, char *);
390 int	pcap_add_if(pcap_if_t **, const char *, u_int, const char *, char *);
391 struct sockaddr *dup_sockaddr(struct sockaddr *, size_t);
392 int	add_or_find_if(pcap_if_t **, pcap_if_t **, const char *, u_int,
393 	    const char *, char *);
394 
395 /*
396  * Internal interfaces for "pcap_open_offline()".
397  *
398  * "pcap_open_offline_common()" allocates and fills in a pcap_t, for use
399  * by pcap_open_offline routines.
400  *
401  * "sf_cleanup()" closes the file handle associated with a pcap_t, if
402  * appropriate, and frees all data common to all modules for handling
403  * savefile types.
404  */
405 pcap_t	*pcap_open_offline_common(char *ebuf, size_t size);
406 void	sf_cleanup(pcap_t *p);
407 
408 /*
409  * Internal interfaces for both "pcap_create()" and routines that
410  * open savefiles.
411  *
412  * "pcap_oneshot()" is the standard one-shot callback for "pcap_next()"
413  * and "pcap_next_ex()".
414  */
415 void	pcap_oneshot(u_char *, const struct pcap_pkthdr *, const u_char *);
416 
417 #ifdef WIN32
418 char	*pcap_win32strerror(void);
419 #endif
420 
421 int	install_bpf_program(pcap_t *, struct bpf_program *);
422 
423 int	pcap_strcasecmp(const char *, const char *);
424 
425 #ifdef __cplusplus
426 }
427 #endif
428 
429 #endif
430