xref: /openbsd/usr.sbin/dhcpd/dhcpd.h (revision 09467b48)
1 /*	$OpenBSD: dhcpd.h,v 1.67 2019/05/08 22:00:55 krw Exp $ */
2 
3 /*
4  * Copyright (c) 1995, 1996, 1997, 1998, 1999
5  * The Internet Software Consortium.    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  *
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. Neither the name of The Internet Software Consortium nor the names
17  *    of its contributors may be used to endorse or promote products derived
18  *    from this software without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE INTERNET SOFTWARE CONSORTIUM AND
21  * CONTRIBUTORS ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
22  * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
23  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
24  * DISCLAIMED.  IN NO EVENT SHALL THE INTERNET SOFTWARE CONSORTIUM OR
25  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
26  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
27  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
28  * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
29  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
30  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
31  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  *
34  * This software has been written for the Internet Software Consortium
35  * by Ted Lemon <mellon@fugue.com> in cooperation with Vixie
36  * Enterprises.  To learn more about the Internet Software Consortium,
37  * see ``http://www.vix.com/isc''.  To learn more about Vixie
38  * Enterprises, see ``http://www.vix.com''.
39  */
40 
41 #define ifr_netmask ifr_addr
42 
43 #define HAVE_SA_LEN
44 #define HAVE_MKSTEMP
45 
46 #define DB_TIMEFMT	"%w %Y/%m/%d %T UTC"
47 #define OLD_DB_TIMEFMT	"%w %Y/%m/%d %T"
48 
49 #define SERVER_PORT	67
50 #define CLIENT_PORT	68
51 
52 struct iaddr {
53 	int len;
54 	unsigned char iabuf[16];
55 };
56 
57 #define DEFAULT_HASH_SIZE	97
58 
59 struct hash_bucket {
60 	struct hash_bucket *next;
61 	unsigned char *name;
62 	int len;
63 	unsigned char *value;
64 };
65 
66 struct hash_table {
67 	int hash_count;
68 	struct hash_bucket *buckets[DEFAULT_HASH_SIZE];
69 };
70 
71 struct option_data {
72 	int len;
73 	u_int8_t *data;
74 };
75 
76 /* A dhcp packet and the pointers to its option values. */
77 struct packet {
78 	struct dhcp_packet *raw;
79 	int packet_length;
80 	int packet_type;
81 	int options_valid;
82 	int client_port;
83 	struct iaddr client_addr;
84 	struct interface_info *interface;	/* Interface on which packet
85 						   was received. */
86 	struct hardware *haddr;		/* Physical link address
87 					   of local sender (maybe gateway). */
88 	struct shared_network *shared_network;
89 	struct option_data options[256];
90 	int got_requested_address;	/* True if client sent the
91 					   dhcp-requested-address option. */
92 };
93 
94 struct hardware {
95 	u_int8_t htype;
96 	u_int8_t hlen;
97 	u_int8_t haddr[16];
98 };
99 
100 /* A dhcp lease declaration structure. */
101 struct lease {
102 	struct lease *next;
103 	struct lease *prev;
104 	struct lease *n_uid, *n_hw;
105 	struct lease *waitq_next;
106 
107 	struct iaddr ip_addr;
108 	time_t starts, ends, timestamp;
109 	unsigned char *uid;
110 	int uid_len;
111 	int uid_max;
112 	unsigned char uid_buf[32];
113 	char *hostname;
114 	char *client_hostname;
115 	uint8_t *client_identifier;
116 	struct host_decl *host;
117 	struct subnet *subnet;
118 	struct shared_network *shared_network;
119 	struct hardware hardware_addr;
120 
121 	int client_identifier_len;
122 	int flags;
123 #define STATIC_LEASE		1
124 #define BOOTP_LEASE		2
125 #define DYNAMIC_BOOTP_OK	4
126 #define PERSISTENT_FLAGS	(DYNAMIC_BOOTP_OK)
127 #define EPHEMERAL_FLAGS		(BOOTP_LEASE)
128 #define MS_NULL_TERMINATION	8
129 #define ABANDONED_LEASE		16
130 #define INFORM_NOLEASE		32
131 
132 	struct lease_state *state;
133 	u_int8_t releasing;
134 };
135 
136 struct lease_state {
137 	struct lease_state *next;
138 
139 	struct interface_info *ip;
140 
141 	time_t offered_expiry;
142 
143 	struct tree_cache *options[256];
144 	u_int32_t expiry, renewal, rebind;
145 	char filename[DHCP_FILE_LEN];
146 	char *server_name;
147 
148 	struct iaddr from;
149 
150 	int max_message_size;
151 	u_int8_t *prl;
152 	int prl_len;
153 	int got_requested_address;	/* True if client sent the
154 					   dhcp-requested-address option. */
155 	int got_server_identifier;	/* True if client sent the
156 					   dhcp-server-identifier option. */
157 	struct shared_network *shared_network;	/* Shared network of interface
158 						   on which request arrived. */
159 
160 	u_int32_t xid;
161 	u_int16_t secs;
162 	u_int16_t bootp_flags;
163 	struct in_addr ciaddr;
164 	struct in_addr giaddr;
165 	u_int8_t hops;
166 	u_int8_t offer;
167 	struct hardware haddr;
168 };
169 
170 #define	ROOT_GROUP	0
171 #define HOST_DECL	1
172 #define SHARED_NET_DECL	2
173 #define SUBNET_DECL	3
174 #define CLASS_DECL	4
175 #define	GROUP_DECL	5
176 
177 /* Group of declarations that share common parameters. */
178 struct group {
179 	struct group *next;
180 
181 	struct subnet *subnet;
182 	struct shared_network *shared_network;
183 
184 	time_t default_lease_time;
185 	time_t max_lease_time;
186 	time_t bootp_lease_cutoff;
187 	time_t bootp_lease_length;
188 
189 	char *filename;
190 	char *server_name;
191 	struct iaddr next_server;
192 
193 	int boot_unknown_clients;
194 	int dynamic_bootp;
195 	int allow_bootp;
196 	int allow_booting;
197 	int get_lease_hostnames;
198 	int use_host_decl_names;
199 	int use_lease_addr_for_default_route;
200 	int authoritative;
201 	int always_reply_rfc1048;
202 	int echo_client_id;
203 
204 	struct tree_cache *options[256];
205 };
206 
207 /* A dhcp host declaration structure. */
208 struct host_decl {
209 	struct host_decl *n_ipaddr;
210 	char *name;
211 	struct hardware interface;
212 	struct tree_cache *fixed_addr;
213 	struct group *group;
214 };
215 
216 struct shared_network {
217 	struct shared_network *next;
218 	char *name;
219 	struct subnet *subnets;
220 	struct interface_info *interface;
221 	struct lease *leases;
222 	struct lease *insertion_point;
223 	struct lease *last_lease;
224 
225 	struct group *group;
226 };
227 
228 struct subnet {
229 	struct subnet *next_subnet;
230 	struct subnet *next_sibling;
231 	struct shared_network *shared_network;
232 	struct interface_info *interface;
233 	struct iaddr interface_address;
234 	struct iaddr net;
235 	struct iaddr netmask;
236 
237 	struct group *group;
238 };
239 
240 struct class {
241 	char *name;
242 
243 	struct group *group;
244 };
245 
246 /* privsep message. fixed length for easy parsing */
247 struct pf_cmd {
248 	struct in_addr ip;
249 	u_int32_t type;
250 };
251 
252 /* Information about each network interface. */
253 
254 struct interface_info {
255 	struct interface_info *next;	/* Next interface in list... */
256 	struct shared_network *shared_network;
257 				/* Networks connected to this interface. */
258 	struct hardware hw_address;	/* Its physical address. */
259 	struct in_addr primary_address;	/* Primary interface address. */
260 	char name[IFNAMSIZ];		/* Its name... */
261 	int rfdesc;			/* Its read file descriptor. */
262 	int wfdesc;			/* Its write file descriptor, if
263 					   different. */
264 	unsigned char *rbuf;		/* Read buffer, if required. */
265 	size_t rbuf_max;		/* Size of read buffer. */
266 	size_t rbuf_offset;		/* Current offset into buffer. */
267 	size_t rbuf_len;		/* Length of data in buffer. */
268 
269 	struct ifreq *ifp;		/* Pointer to ifreq struct. */
270 
271 	int noifmedia;
272 	int errors;
273 	int dead;
274 	u_int16_t	index;
275 	int is_udpsock;
276 	ssize_t (*send_packet)(struct interface_info *, struct dhcp_packet *,
277 	    size_t, struct in_addr, struct sockaddr_in *, struct hardware *);
278 };
279 
280 struct dhcpd_timeout {
281 	struct dhcpd_timeout *next;
282 	time_t when;
283 	void (*func)(void *);
284 	void *what;
285 };
286 
287 struct protocol {
288 	struct protocol *next;
289 	int fd;
290 	void (*handler)(struct protocol *);
291 	void *local;
292 };
293 
294 #define _PATH_DHCPD_CONF	"/etc/dhcpd.conf"
295 #define _PATH_DHCPD_DB		"/var/db/dhcpd.leases"
296 #define _PATH_DEV_PF		"/dev/pf"
297 #define DHCPD_LOG_FACILITY	LOG_DAEMON
298 
299 #define MAX_TIME 0x7fffffff
300 #define MIN_TIME 0
301 
302 /* External definitions... */
303 
304 /* parse.c */
305 extern int warnings_occurred;
306 int	parse_warn(char *, ...) __attribute__ ((__format__ (__printf__, 1,
307 	    2)));
308 
309 /* options.c */
310 void	 parse_options(struct packet *);
311 void	 parse_option_buffer(struct packet *, unsigned char *, int);
312 int	 cons_options(struct packet *, struct dhcp_packet *, int,
313 	    struct tree_cache **, int, int, int, u_int8_t *, int);
314 char	*pretty_print_option(unsigned int, unsigned char *, int, int, int);
315 void	 do_packet(struct interface_info *, struct dhcp_packet *, int,
316 	    unsigned int, struct iaddr, struct hardware *);
317 
318 /* dhcpd.c */
319 extern time_t		cur_time;
320 extern struct group	root_group;
321 
322 extern u_int16_t	server_port;
323 extern u_int16_t	client_port;
324 
325 extern char		*path_dhcpd_conf;
326 extern char		*path_dhcpd_db;
327 
328 int	main(int, char *[]);
329 void	cleanup(void);
330 void	lease_pinged(struct iaddr, u_int8_t *, int);
331 void	lease_ping_timeout(void *);
332 void	periodic_scan(void *);
333 
334 /* conflex.c */
335 extern int	 lexline, lexchar;
336 extern char	*token_line, *tlname;
337 extern char	 comments[4096];
338 extern int	 comment_index;
339 extern int	 eol_token;
340 
341 void	new_parse(char *);
342 int	next_token(char **, FILE *);
343 int	peek_token(char **, FILE *);
344 
345 /* confpars.c */
346 int	 readconf(void);
347 void	 read_leases(void);
348 int	 parse_statement(FILE *, struct group *, int, struct host_decl *, int);
349 void	 parse_allow_deny(FILE *, struct group *, int);
350 void	 skip_to_semi(FILE *);
351 int	 parse_boolean(FILE *);
352 int	 parse_semi(FILE *);
353 int	 parse_lbrace(FILE *);
354 void	 parse_host_declaration(FILE *, struct group *);
355 char	*parse_host_name(FILE *);
356 void	 parse_class_declaration(FILE *, struct group *, int);
357 void	 parse_lease_time(FILE *, time_t *);
358 void	 parse_shared_net_declaration(FILE *, struct group *);
359 void	 parse_subnet_declaration(FILE *, struct shared_network *);
360 void	 parse_group_declaration(FILE *, struct group *);
361 void	 parse_hardware_param(FILE *, struct hardware *);
362 char	*parse_string(FILE *);
363 
364 struct tree		*parse_ip_addr_or_hostname(FILE *, int);
365 struct tree_cache	*parse_fixed_addr_param(FILE *);
366 void			 parse_option_param(FILE *, struct group *);
367 time_t			 parse_timestamp(FILE *);
368 struct lease		*parse_lease_declaration(FILE *);
369 void			 parse_address_range(FILE *, struct subnet *);
370 time_t			 parse_date(FILE *);
371 unsigned char		*parse_numeric_aggregate(FILE *, unsigned char *,
372 			    int *, int, int, int);
373 void			 convert_num(unsigned char *, char *, int, int);
374 struct tree		*parse_domain_and_comp(FILE *);
375 
376 /* tree.c */
377 pair			 cons(caddr_t, pair);
378 struct tree_cache	*tree_cache(struct tree *);
379 struct tree		*tree_host_lookup(char *);
380 struct dns_host_entry	*enter_dns_host(char *);
381 struct tree		*tree_const(unsigned char *, int);
382 struct tree		*tree_concat(struct tree *, struct tree *);
383 struct tree		*tree_limit(struct tree *, int);
384 int			 tree_evaluate(struct tree_cache *);
385 
386 /* dhcp.c */
387 extern int	outstanding_pings;
388 
389 void dhcp(struct packet *, int);
390 void dhcpdiscover(struct packet *);
391 void dhcprequest(struct packet *);
392 void dhcprelease(struct packet *);
393 void dhcpdecline(struct packet *);
394 void dhcpinform(struct packet *);
395 void nak_lease(struct packet *, struct iaddr *cip);
396 void ack_lease(struct packet *, struct lease *, unsigned int, time_t);
397 void dhcp_reply(struct lease *);
398 struct lease *find_lease(struct packet *, struct shared_network *, int *);
399 struct lease *mockup_lease(struct packet *, struct shared_network *,
400     struct host_decl *);
401 
402 /* bootp.c */
403 void bootp(struct packet *);
404 
405 /* memory.c */
406 void enter_host(struct host_decl *);
407 struct host_decl *find_hosts_by_haddr(int, unsigned char *, int);
408 struct host_decl *find_hosts_by_uid(unsigned char *, int);
409 struct subnet *find_host_for_network(struct host_decl **, struct iaddr *,
410     struct shared_network *);
411 void new_address_range(struct iaddr, struct iaddr, struct subnet *, int);
412 extern struct subnet *find_grouped_subnet(struct shared_network *,
413     struct iaddr);
414 extern struct subnet *find_subnet(struct iaddr);
415 void enter_shared_network(struct shared_network *);
416 int subnet_inner_than(struct subnet *, struct subnet *, int);
417 void enter_subnet(struct subnet *);
418 void enter_lease(struct lease *);
419 int supersede_lease(struct lease *, struct lease *, int);
420 void release_lease(struct lease *);
421 void abandon_lease(struct lease *, char *);
422 struct lease *find_lease_by_uid(unsigned char *, int);
423 struct lease *find_lease_by_hw_addr(unsigned char *, int);
424 struct lease *find_lease_by_ip_addr(struct iaddr);
425 void uid_hash_add(struct lease *);
426 void uid_hash_delete(struct lease *);
427 void hw_hash_add(struct lease *);
428 void hw_hash_delete(struct lease *);
429 struct class *add_class(int, char *);
430 struct class *find_class(int, unsigned char *, int);
431 struct group *clone_group(struct group *, char *);
432 void write_leases(void);
433 
434 /* alloc.c */
435 struct tree_cache *new_tree_cache(char *);
436 struct lease_state *new_lease_state(char *);
437 void free_lease_state(struct lease_state *, char *);
438 void free_tree_cache(struct tree_cache *);
439 
440 /* print.c */
441 char *print_hw_addr(int, int, unsigned char *);
442 
443 /* bpf.c */
444 int if_register_bpf(struct interface_info *);
445 void if_register_send(struct interface_info *);
446 void if_register_receive(struct interface_info *);
447 ssize_t receive_packet(struct interface_info *, unsigned char *, size_t,
448     struct sockaddr_in *, struct hardware *);
449 
450 /* dispatch.c */
451 extern struct interface_info *interfaces;
452 extern struct protocol *protocols;
453 extern struct dhcpd_timeout *timeouts;
454 void discover_interfaces(int *);
455 void dispatch(void);
456 int locate_network(struct packet *);
457 void got_one(struct protocol *);
458 void add_timeout(time_t, void (*)(void *), void *);
459 void cancel_timeout(void (*)(void *), void *);
460 void add_protocol (char *, int, void (*)(struct protocol *), void *);
461 void remove_protocol(struct protocol *);
462 
463 /* hash.c */
464 struct hash_table *new_hash(void);
465 void add_hash(struct hash_table *, unsigned char *, int, unsigned char *);
466 void delete_hash_entry(struct hash_table *, unsigned char *, int);
467 unsigned char *hash_lookup(struct hash_table *, unsigned char *, int);
468 
469 /* tables.c */
470 extern struct option dhcp_options[256];
471 extern unsigned char dhcp_option_default_priority_list[256];
472 extern char *hardware_types[256];
473 extern struct hash_table universe_hash;
474 extern struct universe dhcp_universe;
475 void initialize_universes(void);
476 
477 /* convert.c */
478 u_int32_t getULong(unsigned char *);
479 int32_t getLong(unsigned char *);
480 u_int16_t getUShort(unsigned char *);
481 int16_t getShort(unsigned char *);
482 void putULong(unsigned char *, u_int32_t);
483 void putLong(unsigned char *, int32_t);
484 void putUShort(unsigned char *, unsigned int);
485 void putShort(unsigned char *, int);
486 
487 /* inet.c */
488 struct iaddr subnet_number(struct iaddr, struct iaddr);
489 struct iaddr ip_addr(struct iaddr, struct iaddr, u_int32_t);
490 u_int32_t host_addr(struct iaddr, struct iaddr);
491 int addr_eq(struct iaddr, struct iaddr);
492 char *piaddr(struct iaddr);
493 
494 /* db.c */
495 int write_lease(struct lease *);
496 int commit_leases(void);
497 void db_startup(void);
498 void new_lease_file(void);
499 
500 /* packet.c */
501 void assemble_hw_header(struct interface_info *, unsigned char *,
502     int *, struct hardware *);
503 void assemble_udp_ip_header(struct interface_info *, unsigned char *,
504     int *, u_int32_t, u_int32_t, unsigned int, unsigned char *, int);
505 ssize_t decode_hw_header(unsigned char *, u_int32_t, struct hardware *);
506 ssize_t decode_udp_ip_header(unsigned char *, u_int32_t, struct sockaddr_in *);
507 u_int32_t	checksum(unsigned char *, u_int32_t, u_int32_t);
508 u_int32_t	wrapsum(u_int32_t);
509 
510 /* icmp.c */
511 void icmp_startup(int, void (*)(struct iaddr, u_int8_t *, int));
512 int icmp_echorequest(struct iaddr *);
513 void icmp_echoreply(struct protocol *);
514 
515 /* pfutils.c */
516 __dead void pftable_handler(void);
517 void pf_change_table(int, int, struct in_addr, char *);
518 void pf_kill_state(int, struct in_addr);
519 size_t atomicio(ssize_t (*)(int, void *, size_t), int, void *, size_t);
520 #define vwrite (ssize_t (*)(int, void *, size_t))write
521 void pfmsg(char, struct lease *);
522 
523 /* udpsock.c */
524 void udpsock_startup(struct in_addr);
525