1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
|
/* $OpenBSD: dhcpd.h,v 1.149 2015/02/10 04:20:26 krw Exp $ */
/*
* Copyright (c) 2004 Henning Brauer <henning@openbsd.org>
* Copyright (c) 1995, 1996, 1997, 1998, 1999
* The Internet Software Consortium. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of The Internet Software Consortium nor the names
* of its contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE INTERNET SOFTWARE CONSORTIUM AND
* CONTRIBUTORS ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE INTERNET SOFTWARE CONSORTIUM OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
* USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* This software has been written for the Internet Software Consortium
* by Ted Lemon <mellon@fugue.com> in cooperation with Vixie
* Enterprises. To learn more about the Internet Software Consortium,
* see ``http://www.vix.com/isc''. To learn more about Vixie
* Enterprises, see ``http://www.vix.com''.
*/
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/sockio.h>
#include <sys/stat.h>
#include <sys/time.h>
#include <sys/wait.h>
#include <sys/queue.h>
#include <net/if.h>
#include <net/if_dl.h>
#include <net/route.h>
#include <netinet/in.h>
#include <netinet/if_ether.h>
#include <arpa/inet.h>
#include <ctype.h>
#include <errno.h>
#include <fcntl.h>
#include <limits.h>
#include <netdb.h>
#include <paths.h>
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <signal.h>
#include <syslog.h>
#include <time.h>
#include <unistd.h>
#include "dhcp.h"
#define LOCAL_PORT 68
#define REMOTE_PORT 67
#define INTERNALSIG INT_MAX
#define DB_TIMEFMT "%w %Y/%m/%d %T UTC"
#define BAD_DB_TIMEFMT "%u %Y/%m/%d %T"
#define OLD_DB_TIMEFMT "%w %Y/%m/%d %T"
struct option {
char *name;
char *format;
};
struct option_data {
unsigned int len;
u_int8_t *data;
};
struct reject_elem {
TAILQ_ENTRY(reject_elem) next;
struct in_addr addr;
};
struct client_lease {
TAILQ_ENTRY(client_lease) next;
time_t expiry, renewal, rebind;
struct in_addr address;
struct in_addr next_server;
char *server_name;
char *filename;
char *resolv_conf;
unsigned int is_static : 1;
unsigned int is_bootp : 1;
struct option_data options[256];
};
/* Possible states in which the client can be. */
enum dhcp_state {
S_PREBOOT,
S_REBOOTING,
S_INIT,
S_SELECTING,
S_REQUESTING,
S_BOUND,
S_RENEWING,
S_REBINDING
};
struct client_config {
struct option_data defaults[256];
enum {
ACTION_DEFAULT,
ACTION_SUPERSEDE,
ACTION_PREPEND,
ACTION_APPEND
} default_actions[256];
struct in_addr address;
struct in_addr next_server;
struct option_data send_options[256];
u_int8_t required_options[256];
u_int8_t requested_options[256];
u_int8_t ignored_options[256];
int requested_option_count;
int required_option_count;
int ignored_option_count;
time_t timeout;
time_t initial_interval;
time_t link_timeout;
time_t retry_interval;
time_t select_interval;
time_t reboot_timeout;
time_t backoff_cutoff;
enum { IGNORE, ACCEPT, PREFER }
bootp_policy;
TAILQ_HEAD(, reject_elem) reject_list;
char *resolv_tail;
char *filename;
char *server_name;
};
struct client_state {
struct client_lease *active;
struct client_lease *new;
TAILQ_HEAD(, client_lease) offered_leases;
TAILQ_HEAD(_leases, client_lease) leases;
enum dhcp_state state;
struct in_addr destination;
int flags;
#define IS_RESPONSIBLE 0x1
u_int32_t xid;
u_int16_t secs;
time_t first_sending;
time_t startup_time;
time_t interval;
struct dhcp_packet packet;
struct dhcp_packet bootrequest_packet;
int bootrequest_packet_length;
struct in_addr requested_address;
};
struct interface_info {
struct ether_addr hw_address;
char name[IFNAMSIZ];
int bfdesc; /* bpf - reading & broadcast writing*/
int ufdesc; /* udp - unicast writing */
unsigned char *rbuf;
size_t rbuf_max;
size_t rbuf_offset;
size_t rbuf_len;
int errors;
u_int16_t index;
int linkstat;
int rdomain;
int flags;
#define IFI_VALID_LLADDR 0x00000001
#define IFI_NEW_LLADDR 0x00000002
#define IFI_NOMEDIA 0x00000004
#define IFI_HUP 0x00000008
};
struct dhcp_timeout {
time_t when;
void (*func)(void);
};
#define _PATH_DHCLIENT_CONF "/etc/dhclient.conf"
#define _PATH_DHCLIENT_DB "/var/db/dhclient.leases"
/* External definitions. */
extern struct interface_info *ifi;
extern struct client_state *client;
extern struct client_config *config;
extern struct imsgbuf *unpriv_ibuf;
extern struct in_addr deleting;
extern struct in_addr adding;
extern struct in_addr active_addr;
extern volatile sig_atomic_t quit;
/* options.c */
int cons_options(struct option_data *);
char *pretty_print_option(unsigned int, struct option_data *, int);
int pretty_print_string(unsigned char *, size_t, unsigned char *, size_t, int);
void do_packet(unsigned int, struct in_addr, struct ether_addr *);
/* errwarn.c */
extern int warnings_occurred;
void error(char *, ...) __attribute__ ((__format__ (__printf__, 1, 2)));
void warning(char *, ...) __attribute__ ((__format__ (__printf__, 1, 2)));
void note(char *, ...) __attribute__ ((__format__ (__printf__, 1, 2)));
#ifdef DEBUG
void debug(char *, ...) __attribute__ ((__format__ (__printf__, 1, 2)));
#endif
void parse_warn(char *);
/* conflex.c */
extern int lexline, lexchar;
extern char *token_line, *tlname;
void new_parse(char *);
int next_token(char **, FILE *);
int peek_token(char **, FILE *);
/* parse.c */
void skip_to_semi(FILE *);
int parse_semi(FILE *);
char *parse_string(FILE *);
int parse_ip_addr(FILE *, struct in_addr *);
int parse_cidr(FILE *, unsigned char *);
void parse_ethernet(FILE *, struct ether_addr *);
void parse_lease_time(FILE *, time_t *);
int parse_decimal(FILE *, unsigned char *, char);
int parse_hex(FILE *, unsigned char *);
time_t parse_date(FILE *);
/* bpf.c */
void if_register_send(void);
void if_register_receive(void);
ssize_t send_packet(struct in_addr, struct in_addr);
ssize_t receive_packet(struct sockaddr_in *, struct ether_addr *);
/* dispatch.c */
void dispatch(void);
void set_timeout(time_t, void (*)(void));
void set_timeout_interval(time_t, void (*)(void));
void cancel_timeout(void);
void interface_link_forceup(char *);
int interface_status(char *);
int get_rdomain(char *);
void get_hw_address(void);
int subnet_exists(struct client_lease *);
/* tables.c */
extern const struct option dhcp_options[256];
/* dhclient.c */
extern char *path_dhclient_conf;
extern char *path_dhclient_db;
extern int log_perror;
extern int routefd;
void dhcpoffer(struct in_addr, struct option_data *, char *);
void dhcpack(struct in_addr, struct option_data *, char *);
void dhcpnak(struct in_addr, struct option_data *, char *);
void free_client_lease(struct client_lease *);
void routehandler(void);
/* packet.c */
void assemble_eh_header(struct ether_header *);
ssize_t decode_hw_header(unsigned char *, int, struct ether_addr *);
ssize_t decode_udp_ip_header(unsigned char *, int, struct sockaddr_in *,
int);
u_int32_t checksum(unsigned char *, unsigned, u_int32_t);
u_int32_t wrapsum(u_int32_t);
/* clparse.c */
void read_client_conf(void);
void read_client_leases(void);
/* kroute.c */
void delete_addresses(void);
void delete_address(struct in_addr);
void set_interface_mtu(int);
void add_address(struct in_addr, struct in_addr);
void flush_routes(void);
void add_route(struct in_addr, struct in_addr, struct in_addr, struct in_addr,
int, int);
void sendhup(struct client_lease *);
int resolv_conf_priority(void);
void flush_unpriv_ibuf(const char *);
|