1 /** $MirOS: src/usr.sbin/dhcpd/db.c,v 1.2 2005/03/13 19:16:25 tg Exp $ */
2 /* $OpenBSD: db.c,v 1.10 2004/09/16 18:35:42 deraadt Exp $ */
3
4 /*
5 * Persistent database management routines for DHCPD.
6 */
7
8 /*
9 * Copyright (c) 1995, 1996 The Internet Software Consortium.
10 * All rights reserved.
11 *
12 * Redistribution and use in source and binary forms, with or without
13 * modification, are permitted provided that the following conditions
14 * are met:
15 *
16 * 1. Redistributions of source code must retain the above copyright
17 * notice, this list of conditions and the following disclaimer.
18 * 2. Redistributions in binary form must reproduce the above copyright
19 * notice, this list of conditions and the following disclaimer in the
20 * documentation and/or other materials provided with the distribution.
21 * 3. Neither the name of The Internet Software Consortium nor the names
22 * of its contributors may be used to endorse or promote products derived
23 * from this software without specific prior written permission.
24 *
25 * THIS SOFTWARE IS PROVIDED BY THE INTERNET SOFTWARE CONSORTIUM AND
26 * CONTRIBUTORS ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
27 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
28 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
29 * DISCLAIMED. IN NO EVENT SHALL THE INTERNET SOFTWARE CONSORTIUM OR
30 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
31 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
32 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
33 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
34 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
35 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
36 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
37 * SUCH DAMAGE.
38 *
39 * This software has been written for the Internet Software Consortium
40 * by Ted Lemon <mellon@fugue.com> in cooperation with Vixie
41 * Enterprises. To learn more about the Internet Software Consortium,
42 * see ``http://www.vix.com/isc''. To learn more about Vixie
43 * Enterprises, see ``http://www.vix.com''.
44 */
45
46 #include "dhcpd.h"
47
48 __RCSID("$MirOS: src/usr.sbin/dhcpd/db.c,v 1.2 2005/03/13 19:16:25 tg Exp $");
49
50 FILE *db_file;
51
52 static int counting = 0;
53 static int count = 0;
54 time_t write_time;
55
56 /*
57 * Write the specified lease to the current lease database file.
58 */
59 int
write_lease(struct lease * lease)60 write_lease(struct lease *lease)
61 {
62 struct tm *t;
63 char tbuf[64];
64 int errors = 0;
65 int i;
66
67 if (counting)
68 ++count;
69 errno = 0;
70 fprintf(db_file, "lease %s {\n", piaddr(lease->ip_addr));
71 if (errno)
72 ++errors;
73
74 t = gmtime(&lease->starts);
75 snprintf(tbuf, sizeof(tbuf), "%d %lld/%02d/%02d %02d:%02d:%02d;",
76 t->tm_wday, (int64_t)t->tm_year + 1900, t->tm_mon + 1, t->tm_mday,
77 t->tm_hour, t->tm_min, t->tm_sec);
78
79 errno = 0;
80 fprintf(db_file, "\tstarts %s\n", tbuf);
81 if (errno)
82 ++errors;
83
84 t = gmtime(&lease->ends);
85 snprintf(tbuf, sizeof(tbuf), "%d %lld/%02d/%02d %02d:%02d:%02d;",
86 t->tm_wday, (int64_t)t->tm_year + 1900, t->tm_mon + 1, t->tm_mday,
87 t->tm_hour, t->tm_min, t->tm_sec);
88
89 errno = 0;
90 fprintf(db_file, "\tends %s", tbuf);
91 if (errno)
92 ++errors;
93
94 if (lease->hardware_addr.hlen) {
95 errno = 0;
96 fprintf(db_file, "\n\thardware %s %s;",
97 hardware_types[lease->hardware_addr.htype],
98 print_hw_addr(lease->hardware_addr.htype,
99 lease->hardware_addr.hlen,
100 lease->hardware_addr.haddr));
101 if (errno)
102 ++errors;
103 }
104
105 if (lease->uid_len) {
106 int j;
107
108 errno = 0;
109 fprintf(db_file, "\n\tuid %2.2x", lease->uid[0]);
110 if (errno)
111 ++errors;
112
113 for (j = 1; j < lease->uid_len; j++) {
114 errno = 0;
115 fprintf(db_file, ":%2.2x", lease->uid[j]);
116 if (errno)
117 ++errors;
118 }
119 putc(';', db_file);
120 }
121
122 if (lease->flags & BOOTP_LEASE) {
123 errno = 0;
124 fprintf(db_file, "\n\tdynamic-bootp;");
125 if (errno)
126 ++errors;
127 }
128
129 if (lease->flags & ABANDONED_LEASE) {
130 errno = 0;
131 fprintf(db_file, "\n\tabandoned;");
132 if (errno)
133 ++errors;
134 }
135
136 if (lease->client_hostname) {
137 for (i = 0; lease->client_hostname[i]; i++)
138 if (lease->client_hostname[i] < 33 ||
139 lease->client_hostname[i] > 126)
140 goto bad_client_hostname;
141 errno = 0;
142 fprintf(db_file, "\n\tclient-hostname \"%s\";",
143 lease->client_hostname);
144 if (errno)
145 ++errors;
146 }
147
148 bad_client_hostname:
149 if (lease->hostname) {
150 for (i = 0; lease->hostname[i]; i++)
151 if (lease->hostname[i] < 33 ||
152 lease->hostname[i] > 126)
153 goto bad_hostname;
154 errno = 0;
155 fprintf(db_file, "\n\thostname \"%s\";",
156 lease->hostname);
157 if (errno)
158 ++errors;
159 }
160
161 bad_hostname:
162 errno = 0;
163 fputs("\n}\n", db_file);
164 if (errno)
165 ++errors;
166
167 if (errors)
168 note("write_lease: unable to write lease %s",
169 piaddr(lease->ip_addr));
170
171 return (!errors);
172 }
173
174 /*
175 * Commit any leases that have been written out...
176 */
177 int
commit_leases(void)178 commit_leases(void)
179 {
180 /*
181 * Commit any outstanding writes to the lease database file. We need to
182 * do this even if we're rewriting the file below, just in case the
183 * rewrite fails.
184 */
185 if (fflush(db_file) == EOF) {
186 note("commit_leases: unable to commit: %m");
187 return (0);
188 }
189
190 if (fsync(fileno(db_file)) == -1) {
191 note("commit_leases: unable to commit: %m");
192 return (0);
193 }
194
195 /*
196 * If we've written more than a thousand leases or if we haven't
197 * rewritten the lease database in over an hour, rewrite it now.
198 */
199 if (count > 1000 || (count && cur_time - write_time > 3600)) {
200 count = 0;
201 write_time = cur_time;
202 new_lease_file();
203 }
204
205 return (1);
206 }
207
208 void
db_startup(void)209 db_startup(void)
210 {
211 int db_fd;
212
213 /* open lease file. once we dropped privs it has to stay open */
214 db_fd = open(path_dhcpd_db, O_WRONLY|O_CREAT, 0664);
215 if (db_fd == -1)
216 error("Can't create new lease file: %m");
217 if ((db_file = fdopen(db_fd, "w")) == NULL)
218 error("Can't fdopen new lease file!");
219
220 /* Read in the existing lease file... */
221 read_leases();
222 time(&write_time);
223
224 new_lease_file();
225 }
226
227 void
new_lease_file(void)228 new_lease_file(void)
229 {
230 fflush(db_file);
231 rewind(db_file);
232
233 /*
234 * Write an introduction so people don't complain about time being off.
235 */
236 fprintf(db_file, "# All times in this file are in UTC (GMT), "
237 "not your local timezone.\n");
238 fprintf(db_file, "# The format of this file is documented in "
239 "the dhcpd.leases(5) manual page.\n\n");
240
241 /* Write out all the leases that we know of... */
242 counting = 0;
243 write_leases();
244
245 fflush(db_file);
246 ftruncate(fileno(db_file), ftello(db_file));
247 fsync(fileno(db_file));
248
249 counting = 1;
250 }
251