xref: /freebsd/contrib/libpcap/rpcap-protocol.h (revision 7ef62cebc2f965b0f640263e179276928885e33d)
1 /*
2  * Copyright (c) 2002 - 2005 NetGroup, Politecnico di Torino (Italy)
3  * Copyright (c) 2005 - 2008 CACE Technologies, Davis (California)
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  *
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. Neither the name of the Politecnico di Torino, CACE Technologies
16  * nor the names of its contributors may be used to endorse or promote
17  * products derived from this software without specific prior written
18  * permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
21  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
22  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
23  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
24  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
25  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
26  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
27  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
28  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
29  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
30  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
31  *
32  */
33 
34 #ifndef __RPCAP_PROTOCOL_H__
35 #define __RPCAP_PROTOCOL_H__
36 
37 #define RPCAP_DEFAULT_NETPORT "2002" /* Default port on which the RPCAP daemon is waiting for connections. */
38 /* Default port on which the client workstation is waiting for connections in case of active mode. */
39 #define RPCAP_DEFAULT_NETPORT_ACTIVE "2003"
40 #define RPCAP_DEFAULT_NETADDR ""	/* Default network address on which the RPCAP daemon binds to. */
41 
42 /*
43  * Minimum and maximum supported versions of the protocol.
44  *
45  * If new message types are added, the protocol version MUST be changed,
46  * so that a client knows, from the negotiated protocol version, what
47  * messages can be sent to the server.
48  *
49  * If the format of an existing message type is changed, the protocol
50  * version MUST be changed, so that each side knows, from the negotiated
51  * protocol version, what format should be used.
52  *
53  * The RPCAP_MSG_ERROR format MUST not change, as it's used to, among
54  * other things, report "incorrect version number" errors, where, if
55  * the format changed, the sender of the message might not know what
56  * versions the recipient would understand, or might know a version
57  * they support (the version number they sent) but might not know
58  * the format of the message in that version.
59  *
60  * Other message versions SHOULD not change, as that would complicate
61  * the process of interpreting the message, making it version-dependent.
62  * Introducing a new message with a new format is preferable.
63  *
64  * Version negotiation is done as part of the authentication process:
65  *
66  * The client sends an authentication request, with a version number
67  * of 0.  All servers must accept authentication requests with a version
68  * number of 0, even if they don't support version 0 for any other
69  * requests.
70  *
71  * The server attempts to authenticate the client.  If that succeeds,
72  * older servers - which only support version 0 - will send an
73  * authentication reply with no payload.  Newer servers - which might
74  * support other versions - will send an authentication reply with
75  * a payload giving the minimum and maximum versions it supports.
76  *
77  * The client attempts to find the largest version number that is
78  * in both its range of supported versions and the server's supported
79  * versions.  If it fails, it gives up; otherwise, it uses that version.
80  */
81 #define RPCAP_MIN_VERSION 0
82 #define RPCAP_MAX_VERSION 0
83 
84 /*
85  * Version numbers are unsigned, so if RPCAP_MIN_VERSION is 0, they
86  * are >= the minimum version, by definition; don't check against
87  * RPCAP_MIN_VERSION, as you may get compiler warnings that the
88  * comparison will always succeed.
89  */
90 #if RPCAP_MIN_VERSION == 0
91 #define RPCAP_VERSION_IS_SUPPORTED(v)	\
92 	((v) <= RPCAP_MAX_VERSION)
93 #else
94 #define RPCAP_VERSION_IS_SUPPORTED(v)	\
95 	((v) >= RPCAP_MIN_VERSION && (v) <= RPCAP_MAX_VERSION)
96 #endif
97 
98 /*
99  * Separators used for the host list.
100  *
101  * It is used:
102  * - by the rpcapd daemon, when you types a list of allowed connecting hosts
103  * - by the rpcap client in active mode, when the client waits for incoming
104  * connections from other hosts
105  */
106 #define RPCAP_HOSTLIST_SEP " ,;\n\r"
107 
108 /*********************************************************
109  *                                                       *
110  * Protocol messages formats                             *
111  *                                                       *
112  *********************************************************/
113 /*
114  * WARNING: This file defines some structures that are used to transfer
115  * data on the network.
116  * Note that your compiler MUST not insert padding into these structures
117  * for better alignment.
118  * These structures have been created in order to be correctly aligned to
119  * a 32-bit boundary, but be careful in any case.
120  *
121  * The layout of these structures MUST not be changed.  If a packet
122  * format is different in different versions of the protocol, versions
123  * of the structure should be provided for all the different versions or
124  * version ranges (if more than one version of the protocol has the same
125  * layout) that we support.
126  */
127 
128 /*
129  * WARNING: These typedefs MUST be of a specific size.
130  * You might have to change them on your platform.
131  *
132  * XXX - use the C99 types?  Microsoft's newer versions of Visual Studio
133  * support them.
134  */
135 #ifndef __HAIKU__
136 typedef unsigned char uint8;	/* 8-bit unsigned integer */
137 typedef unsigned short uint16;	/* 16-bit unsigned integer */
138 typedef unsigned int uint32;	/* 32-bit unsigned integer */
139 typedef int int32;		/* 32-bit signed integer */
140 #endif
141 
142 /* Common header for all the RPCAP messages */
143 struct rpcap_header
144 {
145 	uint8 ver;	/* RPCAP version number */
146 	uint8 type;	/* RPCAP message type (error, findalldevs, ...) */
147 	uint16 value;	/* Message-dependent value (not always used) */
148 	uint32 plen;	/* Length of the payload of this RPCAP message */
149 };
150 
151 /*
152  * Format of data that may appear at the end of an authentication reply,
153  * giving the minimum and maximum versions of the protocol that the
154  * server supports.
155  *
156  * Older servers don't provide this; they support only version 0.
157  */
158 struct rpcap_authreply
159 {
160 	uint8 minvers;			/* Minimum version supported */
161 	uint8 maxvers;			/* Maximum version supported */
162 	uint8 pad[2];			/* Pad to 4-byte boundary **/
163 	uint32 byte_order_magic;	/* RPCAP_BYTE_ORDER_MAGIC, in server byte order */
164 };
165 
166 /*
167  * Any resemblance between this and the pcap file magic number
168  * is purely coincidental, trust me.
169  */
170 #define RPCAP_BYTE_ORDER_MAGIC		0xa1b2c3d4U
171 #define RPCAP_BYTE_ORDER_MAGIC_SWAPPED	0xd4c3b2a1U
172 
173 /*
174  * Older version of authentication reply, without byte order indication
175  * and padding.
176  */
177 struct rpcap_authreply_old
178 {
179 	uint8 minvers;	/* Minimum version supported */
180 	uint8 maxvers;	/* Maximum version supported */
181 };
182 
183 /* Format of the message for the interface description (findalldevs command) */
184 struct rpcap_findalldevs_if
185 {
186 	uint16 namelen;	/* Length of the interface name */
187 	uint16 desclen;	/* Length of the interface description */
188 	uint32 flags;	/* Interface flags */
189 	uint16 naddr;	/* Number of addresses */
190 	uint16 dummy;	/* Must be zero */
191 };
192 
193 /*
194  * Format of an address as sent over the wire.
195  *
196  * Do *NOT* use struct sockaddr_storage, as the layout for that is
197  * machine-dependent.
198  *
199  * RFC 2553 gives two sample layouts, both of which are 128 bytes long,
200  * both of which are aligned on an 8-byte boundary, and both of which
201  * have 2 bytes before the address data.
202  *
203  * However, one has a 2-byte address family value at the beginning
204  * and the other has a 1-byte address length value and a 1-byte
205  * address family value; this reflects the fact that the original
206  * BSD sockaddr structure had a 2-byte address family value, which
207  * was later changed to a 1-byte address length value and a 1-byte
208  * address family value, when support for variable-length OSI
209  * network-layer addresses was added.
210  *
211  * Furthermore, Solaris's struct sockaddr_storage is 256 bytes
212  * long.
213  *
214  * This structure is supposed to be aligned on an 8-byte boundary;
215  * the message header is 8 bytes long, so we don't have to do
216  * anything to ensure it's aligned on that boundary within a packet,
217  * so we just define it as 128 bytes long, with a 2-byte address
218  * family.  (We only support IPv4 and IPv6 addresses, which are fixed-
219  * length.)  That way, it's the same size as sockaddr_storage on
220  * Windows, and it'll look like what an older Windows client will
221  * expect.
222  *
223  * In addition, do *NOT* use the host's AF_ value for an address,
224  * as the value for AF_INET6 is machine-dependent.  We use the
225  * Windows value, so it'll look like what an older Windows client
226  * will expect.
227  *
228  * (The Windows client is the only one that has been distributed
229  * as a standard part of *pcap; UN*X clients are probably built
230  * from source by the user or administrator, so they're in a
231  * better position to upgrade an old client.  Therefore, we
232  * try to make what goes over the wire look like what comes
233  * from a Windows server.)
234  */
235 struct rpcap_sockaddr
236 {
237 	uint16	family;			/* Address family */
238 	char	data[128-2];		/* Data */
239 };
240 
241 /*
242  * Format of an IPv4 address as sent over the wire.
243  */
244 #define RPCAP_AF_INET	2		/* Value on all OSes */
245 struct rpcap_sockaddr_in
246 {
247 	uint16	family;			/* Address family */
248 	uint16	port;			/* Port number */
249 	uint32	addr;			/* IPv4 address */
250 	uint8	zero[8];		/* Padding */
251 };
252 
253 /*
254  * Format of an IPv6 address as sent over the wire.
255  */
256 #define RPCAP_AF_INET6	23		/* Value on Windows */
257 struct rpcap_sockaddr_in6
258 {
259 	uint16	family;			/* Address family */
260 	uint16	port;			/* Port number */
261 	uint32	flowinfo;		/* IPv6 flow information */
262 	uint8	addr[16];		/* IPv6 address */
263 	uint32	scope_id;		/* Scope zone index */
264 };
265 
266 /* Format of the message for the address listing (findalldevs command) */
267 struct rpcap_findalldevs_ifaddr
268 {
269 	struct rpcap_sockaddr addr;		/* Network address */
270 	struct rpcap_sockaddr netmask;		/* Netmask for that address */
271 	struct rpcap_sockaddr broadaddr;	/* Broadcast address for that address */
272 	struct rpcap_sockaddr dstaddr;		/* P2P destination address for that address */
273 };
274 
275 /*
276  * \brief Format of the message of the connection opening reply (open command).
277  *
278  * This structure transfers over the network some of the values useful on the client side.
279  */
280 struct rpcap_openreply
281 {
282 	int32 linktype;	/* Link type */
283 	int32 tzoff;	/* Timezone offset - not used by newer clients */
284 };
285 
286 /* Format of the message that starts a remote capture (startcap command) */
287 struct rpcap_startcapreq
288 {
289 	uint32 snaplen;		/* Length of the snapshot (number of bytes to capture for each packet) */
290 	uint32 read_timeout;	/* Read timeout in milliseconds */
291 	uint16 flags;		/* Flags (see RPCAP_STARTCAPREQ_FLAG_xxx) */
292 	uint16 portdata;	/* Network port on which the client is waiting at (if 'serveropen') */
293 };
294 
295 /* Format of the reply message that devoted to start a remote capture (startcap reply command) */
296 struct rpcap_startcapreply
297 {
298 	int32 bufsize;		/* Size of the user buffer allocated by WinPcap; it can be different from the one we chose */
299 	uint16 portdata;	/* Network port on which the server is waiting at (passive mode only) */
300 	uint16 dummy;		/* Must be zero */
301 };
302 
303 /*
304  * \brief Format of the header which encapsulates captured packets when transmitted on the network.
305  *
306  * This message requires the general header as well, since we want to be able to exchange
307  * more information across the network in the future (for example statistics, and kind like that).
308  */
309 struct rpcap_pkthdr
310 {
311 	/*
312 	 * This protocol needs to be updated with a new version before
313 	 * 2038-01-19 03:14:07 UTC.
314 	 */
315 	uint32 timestamp_sec;	/* 'struct timeval' compatible, it represents the 'tv_sec' field */
316 	uint32 timestamp_usec;	/* 'struct timeval' compatible, it represents the 'tv_usec' field */
317 	uint32 caplen;		/* Length of portion present in the capture */
318 	uint32 len;		/* Real length of this packet (off wire) */
319 	uint32 npkt;		/* Ordinal number of the packet (i.e. the first one captured has '1', the second one '2', etc) */
320 };
321 
322 /* General header used for the pcap_setfilter() command; keeps just the number of BPF instructions */
323 struct rpcap_filter
324 {
325 	uint16 filtertype;	/* type of the filter transferred (BPF instructions, ...) */
326 	uint16 dummy;		/* Must be zero */
327 	uint32 nitems;		/* Number of items contained into the filter (e.g. BPF instructions for BPF filters) */
328 };
329 
330 /* Structure that keeps a single BPF instruction; it is repeated 'ninsn' times according to the 'rpcap_filterbpf' header */
331 struct rpcap_filterbpf_insn
332 {
333 	uint16 code;	/* opcode of the instruction */
334 	uint8 jt;	/* relative offset to jump to in case of 'true' */
335 	uint8 jf;	/* relative offset to jump to in case of 'false' */
336 	int32 k;	/* instruction-dependent value */
337 };
338 
339 /* Structure that keeps the data required for the authentication on the remote host */
340 struct rpcap_auth
341 {
342 	uint16 type;	/* Authentication type */
343 	uint16 dummy;	/* Must be zero */
344 	uint16 slen1;	/* Length of the first authentication item (e.g. username) */
345 	uint16 slen2;	/* Length of the second authentication item (e.g. password) */
346 };
347 
348 /* Structure that keeps the statistics about the number of packets captured, dropped, etc. */
349 struct rpcap_stats
350 {
351 	uint32 ifrecv;		/* Packets received by the kernel filter (i.e. pcap_stats.ps_recv) */
352 	uint32 ifdrop;		/* Packets dropped by the network interface (e.g. not enough buffers) (i.e. pcap_stats.ps_ifdrop) */
353 	uint32 krnldrop;	/* Packets dropped by the kernel filter (i.e. pcap_stats.ps_drop) */
354 	uint32 svrcapt;		/* Packets captured by the RPCAP daemon and sent on the network */
355 };
356 
357 /* Structure that is needed to set sampling parameters */
358 struct rpcap_sampling
359 {
360 	uint8 method;	/* Sampling method */
361 	uint8 dummy1;	/* Must be zero */
362 	uint16 dummy2;	/* Must be zero */
363 	uint32 value;	/* Parameter related to the sampling method */
364 };
365 
366 /*
367  * Messages field coding.
368  *
369  * These values are used in messages sent over the network, and MUST
370  * not be changed.
371  */
372 #define RPCAP_MSG_IS_REPLY		0x080	/* Flag indicating a reply */
373 
374 #define RPCAP_MSG_ERROR			0x01	/* Message that keeps an error notification */
375 #define RPCAP_MSG_FINDALLIF_REQ		0x02	/* Request to list all the remote interfaces */
376 #define RPCAP_MSG_OPEN_REQ		0x03	/* Request to open a remote device */
377 #define RPCAP_MSG_STARTCAP_REQ		0x04	/* Request to start a capture on a remote device */
378 #define RPCAP_MSG_UPDATEFILTER_REQ	0x05	/* Send a compiled filter into the remote device */
379 #define RPCAP_MSG_CLOSE			0x06	/* Close the connection with the remote peer */
380 #define RPCAP_MSG_PACKET		0x07	/* This is a 'data' message, which carries a network packet */
381 #define RPCAP_MSG_AUTH_REQ		0x08	/* Message that keeps the authentication parameters */
382 #define RPCAP_MSG_STATS_REQ		0x09	/* It requires to have network statistics */
383 #define RPCAP_MSG_ENDCAP_REQ		0x0A	/* Stops the current capture, keeping the device open */
384 #define RPCAP_MSG_SETSAMPLING_REQ	0x0B	/* Set sampling parameters */
385 
386 #define RPCAP_MSG_FINDALLIF_REPLY	(RPCAP_MSG_FINDALLIF_REQ | RPCAP_MSG_IS_REPLY)		/* Keeps the list of all the remote interfaces */
387 #define RPCAP_MSG_OPEN_REPLY		(RPCAP_MSG_OPEN_REQ | RPCAP_MSG_IS_REPLY)		/* The remote device has been opened correctly */
388 #define RPCAP_MSG_STARTCAP_REPLY	(RPCAP_MSG_STARTCAP_REQ | RPCAP_MSG_IS_REPLY)		/* The capture is starting correctly */
389 #define RPCAP_MSG_UPDATEFILTER_REPLY	(RPCAP_MSG_UPDATEFILTER_REQ | RPCAP_MSG_IS_REPLY)	/* The filter has been applied correctly on the remote device */
390 #define RPCAP_MSG_AUTH_REPLY		(RPCAP_MSG_AUTH_REQ | RPCAP_MSG_IS_REPLY)		/* Sends a message that says 'ok, authorization successful' */
391 #define RPCAP_MSG_STATS_REPLY		(RPCAP_MSG_STATS_REQ | RPCAP_MSG_IS_REPLY)		/* Message that keeps the network statistics */
392 #define RPCAP_MSG_ENDCAP_REPLY		(RPCAP_MSG_ENDCAP_REQ | RPCAP_MSG_IS_REPLY)		/* Confirms that the capture stopped successfully */
393 #define RPCAP_MSG_SETSAMPLING_REPLY	(RPCAP_MSG_SETSAMPLING_REQ | RPCAP_MSG_IS_REPLY)		/* Confirms that the capture stopped successfully */
394 
395 #define RPCAP_STARTCAPREQ_FLAG_PROMISC		0x00000001	/* Enables promiscuous mode (default: disabled) */
396 #define RPCAP_STARTCAPREQ_FLAG_DGRAM		0x00000002	/* Use a datagram (i.e. UDP) connection for the data stream (default: use TCP)*/
397 #define RPCAP_STARTCAPREQ_FLAG_SERVEROPEN	0x00000004	/* The server has to open the data connection toward the client */
398 #define RPCAP_STARTCAPREQ_FLAG_INBOUND		0x00000008	/* Capture only inbound packets (take care: the flag has no effect with promiscuous enabled) */
399 #define RPCAP_STARTCAPREQ_FLAG_OUTBOUND		0x00000010	/* Capture only outbound packets (take care: the flag has no effect with promiscuous enabled) */
400 
401 #define RPCAP_UPDATEFILTER_BPF 1			/* This code tells us that the filter is encoded with the BPF/NPF syntax */
402 
403 /*
404  * Network error codes.
405  *
406  * These values are used in messages sent over the network, and MUST
407  * not be changed.
408  */
409 #define PCAP_ERR_NETW			1	/* Network error */
410 #define PCAP_ERR_INITTIMEOUT		2	/* The RPCAP initial timeout has expired */
411 #define PCAP_ERR_AUTH			3	/* Generic authentication error */
412 #define PCAP_ERR_FINDALLIF		4	/* Generic findalldevs error */
413 #define PCAP_ERR_NOREMOTEIF		5	/* The findalldevs was ok, but the remote end had no interfaces to list */
414 #define PCAP_ERR_OPEN			6	/* Generic pcap_open error */
415 #define PCAP_ERR_UPDATEFILTER		7	/* Generic updatefilter error */
416 #define PCAP_ERR_GETSTATS		8	/* Generic pcap_stats error */
417 #define PCAP_ERR_READEX			9	/* Generic pcap_next_ex error */
418 #define PCAP_ERR_HOSTNOAUTH		10	/* The host is not authorized to connect to this server */
419 #define PCAP_ERR_REMOTEACCEPT		11	/* Generic pcap_remoteaccept error */
420 #define PCAP_ERR_STARTCAPTURE		12	/* Generic pcap_startcapture error */
421 #define PCAP_ERR_ENDCAPTURE		13	/* Generic pcap_endcapture error */
422 #define PCAP_ERR_RUNTIMETIMEOUT		14	/* The RPCAP run-time timeout has expired */
423 #define PCAP_ERR_SETSAMPLING		15	/* Error during the settings of sampling parameters */
424 #define PCAP_ERR_WRONGMSG		16	/* The other end endpoint sent a message which has not been recognized */
425 #define PCAP_ERR_WRONGVER		17	/* The other end endpoint has a version number that is not compatible with our */
426 #define PCAP_ERR_AUTH_FAILED		18	/* The user couldn't be authenticated */
427 #define PCAP_ERR_TLS_REQUIRED		19	/* The server requires TLS to connect */
428 #define PCAP_ERR_AUTH_TYPE_NOTSUP	20	/* The authentication type isn't supported */
429 
430 /*
431  * \brief Buffer used by socket functions to send-receive packets.
432  * In case you plan to have messages larger than this value, you have to increase it.
433  */
434 #define RPCAP_NETBUF_SIZE 64000
435 
436 /*********************************************************
437  *                                                       *
438  * Routines used by the rpcap client and rpcap daemon    *
439  *                                                       *
440  *********************************************************/
441 
442 #include "sockutils.h"
443 #include "sslutils.h"
444 
445 extern void rpcap_createhdr(struct rpcap_header *header, uint8 ver, uint8 type, uint16 value, uint32 length);
446 extern const char *rpcap_msg_type_string(uint8 type);
447 extern int rpcap_senderror(SOCKET sock, SSL *ssl, uint8 ver, uint16 errcode, const char *error, char *errbuf);
448 
449 #endif
450