1 /*
2 * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
3 * Copyright (c) 1996,1999 by Internet Software Consortium.
4 *
5 * Permission to use, copy, modify, and distribute this software for any
6 * purpose with or without fee is hereby granted, provided that the above
7 * copyright notice and this permission notice appear in all copies.
8 *
9 * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES
10 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
11 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR
12 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
13 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
14 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
15 * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
16 */
17
18 /* Imports */
19
20 #include "port_before.h"
21
22 #include <sys/types.h>
23
24 #include <netinet/in.h>
25 #include <arpa/nameser.h>
26
27 #include <errno.h>
28 #include <resolv.h>
29 #include <stdlib.h>
30 #include <string.h>
31
32 #include <isc/memcluster.h>
33 #include <irs.h>
34
35 #include "port_after.h"
36
37 #include "irs_p.h"
38 #include "gen_p.h"
39
40 /* Types */
41
42 struct pvt {
43 struct irs_rule * rules;
44 struct irs_rule * rule;
45 struct __res_state * res;
46 void (*free_res)(void *);
47 };
48
49 /* Forward */
50
51 static void nw_close(struct irs_nw*);
52 static struct nwent * nw_next(struct irs_nw *);
53 static struct nwent * nw_byname(struct irs_nw *, const char *, int);
54 static struct nwent * nw_byaddr(struct irs_nw *, void *, int, int);
55 static void nw_rewind(struct irs_nw *);
56 static void nw_minimize(struct irs_nw *);
57 static struct __res_state * nw_res_get(struct irs_nw *this);
58 static void nw_res_set(struct irs_nw *this,
59 struct __res_state *res,
60 void (*free_res)(void *));
61
62 static int init(struct irs_nw *this);
63
64 /* Public */
65
66 struct irs_nw *
irs_gen_nw(struct irs_acc * this)67 irs_gen_nw(struct irs_acc *this) {
68 struct gen_p *accpvt = (struct gen_p *)this->private;
69 struct irs_nw *nw;
70 struct pvt *pvt;
71
72 if (!(pvt = memget(sizeof *pvt))) {
73 errno = ENOMEM;
74 return (NULL);
75 }
76 memset(pvt, 0, sizeof *pvt);
77 if (!(nw = memget(sizeof *nw))) {
78 memput(pvt, sizeof *pvt);
79 errno = ENOMEM;
80 return (NULL);
81 }
82 memset(nw, 0x5e, sizeof *nw);
83 pvt->rules = accpvt->map_rules[irs_nw];
84 pvt->rule = pvt->rules;
85 nw->private = pvt;
86 nw->close = nw_close;
87 nw->next = nw_next;
88 nw->byname = nw_byname;
89 nw->byaddr = nw_byaddr;
90 nw->rewind = nw_rewind;
91 nw->minimize = nw_minimize;
92 nw->res_get = nw_res_get;
93 nw->res_set = nw_res_set;
94 return (nw);
95 }
96
97 /* Methods */
98
99 static void
nw_close(struct irs_nw * this)100 nw_close(struct irs_nw *this) {
101 struct pvt *pvt = (struct pvt *)this->private;
102
103 nw_minimize(this);
104
105 if (pvt->res && pvt->free_res)
106 (*pvt->free_res)(pvt->res);
107
108 memput(pvt, sizeof *pvt);
109 memput(this, sizeof *this);
110 }
111
112 static struct nwent *
nw_next(struct irs_nw * this)113 nw_next(struct irs_nw *this) {
114 struct pvt *pvt = (struct pvt *)this->private;
115 struct nwent *rval;
116 struct irs_nw *nw;
117
118 if (init(this) == -1)
119 return(NULL);
120
121 while (pvt->rule) {
122 nw = pvt->rule->inst->nw;
123 rval = (*nw->next)(nw);
124 if (rval)
125 return (rval);
126 if (!(pvt->rules->flags & IRS_CONTINUE))
127 break;
128 pvt->rule = pvt->rule->next;
129 if (pvt->rule) {
130 nw = pvt->rule->inst->nw;
131 (*nw->rewind)(nw);
132 }
133 }
134 return (NULL);
135 }
136
137 static struct nwent *
nw_byname(struct irs_nw * this,const char * name,int type)138 nw_byname(struct irs_nw *this, const char *name, int type) {
139 struct pvt *pvt = (struct pvt *)this->private;
140 struct irs_rule *rule;
141 struct nwent *rval;
142 struct irs_nw *nw;
143
144 if (init(this) == -1)
145 return(NULL);
146
147 for (rule = pvt->rules; rule; rule = rule->next) {
148 nw = rule->inst->nw;
149 RES_SET_H_ERRNO(pvt->res, NETDB_INTERNAL);
150 rval = (*nw->byname)(nw, name, type);
151 if (rval != NULL)
152 return (rval);
153 if (pvt->res->res_h_errno != TRY_AGAIN &&
154 !(rule->flags & IRS_CONTINUE))
155 break;
156 }
157 return (NULL);
158 }
159
160 static struct nwent *
nw_byaddr(struct irs_nw * this,void * net,int length,int type)161 nw_byaddr(struct irs_nw *this, void *net, int length, int type) {
162 struct pvt *pvt = (struct pvt *)this->private;
163 struct irs_rule *rule;
164 struct nwent *rval;
165 struct irs_nw *nw;
166
167 if (init(this) == -1)
168 return(NULL);
169
170 for (rule = pvt->rules; rule; rule = rule->next) {
171 nw = rule->inst->nw;
172 RES_SET_H_ERRNO(pvt->res, NETDB_INTERNAL);
173 rval = (*nw->byaddr)(nw, net, length, type);
174 if (rval != NULL)
175 return (rval);
176 if (pvt->res->res_h_errno != TRY_AGAIN &&
177 !(rule->flags & IRS_CONTINUE))
178 break;
179 }
180 return (NULL);
181 }
182
183 static void
nw_rewind(struct irs_nw * this)184 nw_rewind(struct irs_nw *this) {
185 struct pvt *pvt = (struct pvt *)this->private;
186 struct irs_nw *nw;
187
188 pvt->rule = pvt->rules;
189 if (pvt->rule) {
190 nw = pvt->rule->inst->nw;
191 (*nw->rewind)(nw);
192 }
193 }
194
195 static void
nw_minimize(struct irs_nw * this)196 nw_minimize(struct irs_nw *this) {
197 struct pvt *pvt = (struct pvt *)this->private;
198 struct irs_rule *rule;
199
200 if (pvt->res)
201 res_nclose(pvt->res);
202 for (rule = pvt->rules; rule != NULL; rule = rule->next) {
203 struct irs_nw *nw = rule->inst->nw;
204
205 (*nw->minimize)(nw);
206 }
207 }
208
209 static struct __res_state *
nw_res_get(struct irs_nw * this)210 nw_res_get(struct irs_nw *this) {
211 struct pvt *pvt = (struct pvt *)this->private;
212
213 if (!pvt->res) {
214 struct __res_state *res;
215 res = (struct __res_state *)malloc(sizeof *res);
216 if (!res) {
217 errno = ENOMEM;
218 return (NULL);
219 }
220 memset(res, 0, sizeof *res);
221 nw_res_set(this, res, free);
222 }
223
224 return (pvt->res);
225 }
226
227 static void
nw_res_set(struct irs_nw * this,struct __res_state * res,void (* free_res)(void *))228 nw_res_set(struct irs_nw *this, struct __res_state *res,
229 void (*free_res)(void *)) {
230 struct pvt *pvt = (struct pvt *)this->private;
231 struct irs_rule *rule;
232
233 if (pvt->res && pvt->free_res) {
234 res_nclose(pvt->res);
235 (*pvt->free_res)(pvt->res);
236 }
237
238 pvt->res = res;
239 pvt->free_res = free_res;
240
241 for (rule = pvt->rules; rule != NULL; rule = rule->next) {
242 struct irs_nw *nw = rule->inst->nw;
243
244 (*nw->res_set)(nw, pvt->res, NULL);
245 }
246 }
247
248 static int
init(struct irs_nw * this)249 init(struct irs_nw *this) {
250 struct pvt *pvt = (struct pvt *)this->private;
251
252 if (!pvt->res && !nw_res_get(this))
253 return (-1);
254 if (((pvt->res->options & RES_INIT) == 0U) &&
255 res_ninit(pvt->res) == -1)
256 return (-1);
257 return (0);
258 }
259
260 /*! \file */
261