1 /* $NetBSD: forward.c,v 1.5 2014/12/10 04:37:58 christos Exp $ */
2
3 /*
4 * Copyright (C) 2004, 2005, 2007, 2009, 2013 Internet Systems Consortium, Inc. ("ISC")
5 * Copyright (C) 2000, 2001 Internet Software Consortium.
6 *
7 * Permission to use, copy, modify, and/or distribute this software for any
8 * purpose with or without fee is hereby granted, provided that the above
9 * copyright notice and this permission notice appear in all copies.
10 *
11 * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
12 * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
13 * AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
14 * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
15 * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
16 * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
17 * PERFORMANCE OF THIS SOFTWARE.
18 */
19
20 /* Id: forward.c,v 1.14 2009/09/02 23:48:02 tbox Exp */
21
22 /*! \file */
23
24 #include <config.h>
25
26 #include <isc/magic.h>
27 #include <isc/mem.h>
28 #include <isc/rwlock.h>
29 #include <isc/sockaddr.h>
30 #include <isc/util.h>
31
32 #include <dns/forward.h>
33 #include <dns/rbt.h>
34 #include <dns/result.h>
35 #include <dns/types.h>
36
37 struct dns_fwdtable {
38 /* Unlocked. */
39 unsigned int magic;
40 isc_mem_t *mctx;
41 isc_rwlock_t rwlock;
42 /* Locked by lock. */
43 dns_rbt_t *table;
44 };
45
46 #define FWDTABLEMAGIC ISC_MAGIC('F', 'w', 'd', 'T')
47 #define VALID_FWDTABLE(ft) ISC_MAGIC_VALID(ft, FWDTABLEMAGIC)
48
49 static void
50 auto_detach(void *, void *);
51
52 isc_result_t
dns_fwdtable_create(isc_mem_t * mctx,dns_fwdtable_t ** fwdtablep)53 dns_fwdtable_create(isc_mem_t *mctx, dns_fwdtable_t **fwdtablep) {
54 dns_fwdtable_t *fwdtable;
55 isc_result_t result;
56
57 REQUIRE(fwdtablep != NULL && *fwdtablep == NULL);
58
59 fwdtable = isc_mem_get(mctx, sizeof(dns_fwdtable_t));
60 if (fwdtable == NULL)
61 return (ISC_R_NOMEMORY);
62
63 fwdtable->table = NULL;
64 result = dns_rbt_create(mctx, auto_detach, fwdtable, &fwdtable->table);
65 if (result != ISC_R_SUCCESS)
66 goto cleanup_fwdtable;
67
68 result = isc_rwlock_init(&fwdtable->rwlock, 0, 0);
69 if (result != ISC_R_SUCCESS)
70 goto cleanup_rbt;
71
72 fwdtable->mctx = NULL;
73 isc_mem_attach(mctx, &fwdtable->mctx);
74 fwdtable->magic = FWDTABLEMAGIC;
75 *fwdtablep = fwdtable;
76
77 return (ISC_R_SUCCESS);
78
79 cleanup_rbt:
80 dns_rbt_destroy(&fwdtable->table);
81
82 cleanup_fwdtable:
83 isc_mem_put(mctx, fwdtable, sizeof(dns_fwdtable_t));
84
85 return (result);
86 }
87
88 isc_result_t
dns_fwdtable_addfwd(dns_fwdtable_t * fwdtable,dns_name_t * name,dns_forwarderlist_t * fwdrs,dns_fwdpolicy_t fwdpolicy)89 dns_fwdtable_addfwd(dns_fwdtable_t *fwdtable, dns_name_t *name,
90 dns_forwarderlist_t *fwdrs, dns_fwdpolicy_t fwdpolicy)
91 {
92 isc_result_t result;
93 dns_forwarders_t *forwarders;
94 dns_forwarder_t *fwd, *nfwd;
95
96 REQUIRE(VALID_FWDTABLE(fwdtable));
97
98 forwarders = isc_mem_get(fwdtable->mctx, sizeof(dns_forwarders_t));
99 if (forwarders == NULL)
100 return (ISC_R_NOMEMORY);
101
102 ISC_LIST_INIT(forwarders->fwdrs);
103 for (fwd = ISC_LIST_HEAD(*fwdrs);
104 fwd != NULL;
105 fwd = ISC_LIST_NEXT(fwd, link))
106 {
107 nfwd = isc_mem_get(fwdtable->mctx, sizeof(dns_forwarder_t));
108 if (nfwd == NULL) {
109 result = ISC_R_NOMEMORY;
110 goto cleanup;
111 }
112 *nfwd = *fwd;
113 ISC_LINK_INIT(nfwd, link);
114 ISC_LIST_APPEND(forwarders->fwdrs, nfwd, link);
115 }
116 forwarders->fwdpolicy = fwdpolicy;
117
118 RWLOCK(&fwdtable->rwlock, isc_rwlocktype_write);
119 result = dns_rbt_addname(fwdtable->table, name, forwarders);
120 RWUNLOCK(&fwdtable->rwlock, isc_rwlocktype_write);
121
122 if (result != ISC_R_SUCCESS)
123 goto cleanup;
124
125 return (ISC_R_SUCCESS);
126
127 cleanup:
128 while (!ISC_LIST_EMPTY(forwarders->fwdrs)) {
129 fwd = ISC_LIST_HEAD(forwarders->fwdrs);
130 ISC_LIST_UNLINK(forwarders->fwdrs, fwd, link);
131 isc_mem_put(fwdtable->mctx, fwd, sizeof(isc_sockaddr_t));
132 }
133 isc_mem_put(fwdtable->mctx, forwarders, sizeof(dns_forwarders_t));
134 return (result);
135 }
136
137 isc_result_t
dns_fwdtable_add(dns_fwdtable_t * fwdtable,dns_name_t * name,isc_sockaddrlist_t * addrs,dns_fwdpolicy_t fwdpolicy)138 dns_fwdtable_add(dns_fwdtable_t *fwdtable, dns_name_t *name,
139 isc_sockaddrlist_t *addrs, dns_fwdpolicy_t fwdpolicy)
140 {
141 isc_result_t result;
142 dns_forwarders_t *forwarders;
143 dns_forwarder_t *fwd;
144 isc_sockaddr_t *sa;
145
146 REQUIRE(VALID_FWDTABLE(fwdtable));
147
148 forwarders = isc_mem_get(fwdtable->mctx, sizeof(dns_forwarders_t));
149 if (forwarders == NULL)
150 return (ISC_R_NOMEMORY);
151
152 ISC_LIST_INIT(forwarders->fwdrs);
153 for (sa = ISC_LIST_HEAD(*addrs);
154 sa != NULL;
155 sa = ISC_LIST_NEXT(sa, link))
156 {
157 fwd = isc_mem_get(fwdtable->mctx, sizeof(dns_forwarder_t));
158 if (fwd == NULL) {
159 result = ISC_R_NOMEMORY;
160 goto cleanup;
161 }
162 fwd->addr = *sa;
163 fwd->dscp = -1;
164 ISC_LINK_INIT(fwd, link);
165 ISC_LIST_APPEND(forwarders->fwdrs, fwd, link);
166 }
167 forwarders->fwdpolicy = fwdpolicy;
168
169 RWLOCK(&fwdtable->rwlock, isc_rwlocktype_write);
170 result = dns_rbt_addname(fwdtable->table, name, forwarders);
171 RWUNLOCK(&fwdtable->rwlock, isc_rwlocktype_write);
172
173 if (result != ISC_R_SUCCESS)
174 goto cleanup;
175
176 return (ISC_R_SUCCESS);
177
178 cleanup:
179 while (!ISC_LIST_EMPTY(forwarders->fwdrs)) {
180 fwd = ISC_LIST_HEAD(forwarders->fwdrs);
181 ISC_LIST_UNLINK(forwarders->fwdrs, fwd, link);
182 isc_mem_put(fwdtable->mctx, fwd, sizeof(dns_forwarder_t));
183 }
184 isc_mem_put(fwdtable->mctx, forwarders, sizeof(dns_forwarders_t));
185 return (result);
186 }
187
188 isc_result_t
dns_fwdtable_delete(dns_fwdtable_t * fwdtable,dns_name_t * name)189 dns_fwdtable_delete(dns_fwdtable_t *fwdtable, dns_name_t *name) {
190 isc_result_t result;
191
192 REQUIRE(VALID_FWDTABLE(fwdtable));
193
194 RWLOCK(&fwdtable->rwlock, isc_rwlocktype_write);
195 result = dns_rbt_deletename(fwdtable->table, name, ISC_FALSE);
196 RWUNLOCK(&fwdtable->rwlock, isc_rwlocktype_write);
197
198 if (result == DNS_R_PARTIALMATCH)
199 result = ISC_R_NOTFOUND;
200
201 return (result);
202 }
203
204 isc_result_t
dns_fwdtable_find(dns_fwdtable_t * fwdtable,dns_name_t * name,dns_forwarders_t ** forwardersp)205 dns_fwdtable_find(dns_fwdtable_t *fwdtable, dns_name_t *name,
206 dns_forwarders_t **forwardersp)
207 {
208 return (dns_fwdtable_find2(fwdtable, name, NULL, forwardersp));
209 }
210
211 isc_result_t
dns_fwdtable_find2(dns_fwdtable_t * fwdtable,dns_name_t * name,dns_name_t * foundname,dns_forwarders_t ** forwardersp)212 dns_fwdtable_find2(dns_fwdtable_t *fwdtable, dns_name_t *name,
213 dns_name_t *foundname, dns_forwarders_t **forwardersp)
214 {
215 isc_result_t result;
216
217 REQUIRE(VALID_FWDTABLE(fwdtable));
218
219 RWLOCK(&fwdtable->rwlock, isc_rwlocktype_read);
220
221 result = dns_rbt_findname(fwdtable->table, name, 0, foundname,
222 (void **)forwardersp);
223 if (result == DNS_R_PARTIALMATCH)
224 result = ISC_R_SUCCESS;
225
226 RWUNLOCK(&fwdtable->rwlock, isc_rwlocktype_read);
227
228 return (result);
229 }
230
231 void
dns_fwdtable_destroy(dns_fwdtable_t ** fwdtablep)232 dns_fwdtable_destroy(dns_fwdtable_t **fwdtablep) {
233 dns_fwdtable_t *fwdtable;
234 isc_mem_t *mctx;
235
236 REQUIRE(fwdtablep != NULL && VALID_FWDTABLE(*fwdtablep));
237
238 fwdtable = *fwdtablep;
239
240 dns_rbt_destroy(&fwdtable->table);
241 isc_rwlock_destroy(&fwdtable->rwlock);
242 fwdtable->magic = 0;
243 mctx = fwdtable->mctx;
244 isc_mem_put(mctx, fwdtable, sizeof(dns_fwdtable_t));
245 isc_mem_detach(&mctx);
246
247 *fwdtablep = NULL;
248 }
249
250 /***
251 *** Private
252 ***/
253
254 static void
auto_detach(void * data,void * arg)255 auto_detach(void *data, void *arg) {
256 dns_forwarders_t *forwarders = data;
257 dns_fwdtable_t *fwdtable = arg;
258 dns_forwarder_t *fwd;
259
260 UNUSED(arg);
261
262 while (!ISC_LIST_EMPTY(forwarders->fwdrs)) {
263 fwd = ISC_LIST_HEAD(forwarders->fwdrs);
264 ISC_LIST_UNLINK(forwarders->fwdrs, fwd, link);
265 isc_mem_put(fwdtable->mctx, fwd, sizeof(dns_forwarder_t));
266 }
267 isc_mem_put(fwdtable->mctx, forwarders, sizeof(dns_forwarders_t));
268 }
269