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
|
/* $OpenBSD: db.c,v 1.6 2004/04/18 00:43:27 deraadt Exp $ */
/*
* Persistent database management routines for DHCPD.
*/
/*
* Copyright (c) 1995, 1996 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 "dhcpd.h"
FILE *db_file;
static int counting = 0;
static int count = 0;
time_t write_time;
/*
* Write the specified lease to the current lease database file.
*/
int
write_lease(struct lease *lease)
{
struct tm *t;
char tbuf[64];
int errors = 0;
int i;
if (counting)
++count;
errno = 0;
fprintf(db_file, "lease %s {\n", piaddr(lease->ip_addr));
if (errno)
++errors;
t = gmtime(&lease->starts);
snprintf(tbuf, sizeof(tbuf), "%d %d/%02d/%02d %02d:%02d:%02d;",
t->tm_wday, t->tm_year + 1900, t->tm_mon + 1, t->tm_mday,
t->tm_hour, t->tm_min, t->tm_sec);
errno = 0;
fprintf(db_file, "\tstarts %s\n", tbuf);
if (errno)
++errors;
t = gmtime(&lease->ends);
snprintf(tbuf, sizeof(tbuf), "%d %d/%02d/%02d %02d:%02d:%02d;",
t->tm_wday, t->tm_year + 1900, t->tm_mon + 1, t->tm_mday,
t->tm_hour, t->tm_min, t->tm_sec);
errno = 0;
fprintf(db_file, "\tends %s", tbuf);
if (errno)
++errors;
if (lease->hardware_addr.hlen) {
errno = 0;
fprintf(db_file, "\n\thardware %s %s;",
hardware_types[lease->hardware_addr.htype],
print_hw_addr(lease->hardware_addr.htype,
lease->hardware_addr.hlen,
lease->hardware_addr.haddr));
if (errno)
++errors;
}
if (lease->uid_len) {
int i;
errno = 0;
fprintf(db_file, "\n\tuid %2.2x", lease->uid[0]);
if (errno)
++errors;
for (i = 1; i < lease->uid_len; i++) {
errno = 0;
fprintf(db_file, ":%2.2x", lease->uid[i]);
if (errno)
++errors;
}
putc (';', db_file);
}
if (lease->flags & BOOTP_LEASE) {
errno = 0;
fprintf(db_file, "\n\tdynamic-bootp;");
if (errno)
++errors;
}
if (lease->flags & ABANDONED_LEASE) {
errno = 0;
fprintf(db_file, "\n\tabandoned;");
if (errno)
++errors;
}
if (lease->client_hostname) {
for (i = 0; lease->client_hostname[i]; i++)
if (lease->client_hostname[i] < 33 ||
lease->client_hostname[i] > 126)
goto bad_client_hostname;
errno = 0;
fprintf(db_file, "\n\tclient-hostname \"%s\";",
lease->client_hostname);
if (errno)
++errors;
}
bad_client_hostname:
if (lease->hostname) {
for (i = 0; lease->hostname[i]; i++)
if (lease->hostname[i] < 33 ||
lease->hostname[i] > 126)
goto bad_hostname;
errno = 0;
fprintf(db_file, "\n\thostname \"%s\";",
lease->hostname);
if (errno)
++errors;
}
bad_hostname:
errno = 0;
fputs("\n}\n", db_file);
if (errno)
++errors;
if (errors)
note("write_lease: unable to write lease %s",
piaddr(lease->ip_addr));
return (!errors);
}
/*
* Commit any leases that have been written out...
*/
int
commit_leases(void)
{
/*
* Commit any outstanding writes to the lease database file. We need to
* do this even if we're rewriting the file below, just in case the
* rewrite fails.
*/
if (fflush(db_file) == EOF) {
note("commit_leases: unable to commit: %m");
return (0);
}
if (fsync(fileno(db_file)) == -1) {
note("commit_leases: unable to commit: %m");
return (0);
}
/*
* If we've written more than a thousand leases or if we haven't
* rewritten the lease database in over an hour, rewrite it now.
*/
if (count > 1000 || (count && cur_time - write_time > 3600)) {
count = 0;
write_time = cur_time;
new_lease_file();
}
return (1);
}
void
db_startup(void)
{
int db_fd;
/* open lease file. once we dropped privs it has to stay open */
db_fd = open(path_dhcpd_db, O_WRONLY|O_TRUNC|O_CREAT, 0664);
if (db_fd == -1)
error("Can't create new lease file: %m");
if ((db_file = fdopen(db_fd, "w")) == NULL)
error("Can't fdopen new lease file!");
/* Read in the existing lease file... */
read_leases();
time(&write_time);
new_lease_file();
}
void
new_lease_file()
{
fflush(db_file);
rewind(db_file);
/*
* Write an introduction so people don't complain about time being off.
*/
fprintf(db_file, "# All times in this file are in UTC (GMT), "
"not your local timezone.\n");
fprintf(db_file, "# The format of this file is documented in "
"the dhcpd.leases(5) manual page.\n\n");
/* Write out all the leases that we know of... */
counting = 0;
write_leases();
fflush(db_file);
ftruncate(fileno(db_file), ftell(db_file));
fsync(fileno(db_file));
counting = 1;
}
|