xref: /titanic_41/usr/src/lib/libresolv2/common/irs/gen_nw.c (revision 59ac0c1669407488b67ae9e273667a340dccc611)
1 /*
2  * Copyright (c) 1997-2000 by Sun Microsystems, Inc.
3  * All rights reserved.
4  */
5 
6 /*
7  * Copyright (c) 1996,1999 by Internet Software Consortium.
8  *
9  * Permission to use, copy, modify, and distribute this software for any
10  * purpose with or without fee is hereby granted, provided that the above
11  * copyright notice and this permission notice appear in all copies.
12  *
13  * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM DISCLAIMS
14  * ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES
15  * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE
16  * CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
17  * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
18  * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
19  * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
20  * SOFTWARE.
21  */
22 
23 #pragma ident	"%Z%%M%	%I%	%E% SMI"
24 
25 #if !defined(LINT) && !defined(CODECENTER)
26 static const char rcsid[] = "$Id: gen_nw.c,v 1.13 1999/10/13 16:39:29 vixie Exp $";
27 #endif
28 
29 /* Imports */
30 
31 #include "port_before.h"
32 
33 #include <sys/types.h>
34 
35 #include <netinet/in.h>
36 #include <arpa/nameser.h>
37 
38 #include <errno.h>
39 #include <resolv.h>
40 #include <stdlib.h>
41 #include <string.h>
42 
43 #include <isc/memcluster.h>
44 #include <irs.h>
45 
46 #include "port_after.h"
47 
48 #include "irs_p.h"
49 #include "gen_p.h"
50 
51 /* Types */
52 
53 struct pvt {
54 	struct irs_rule *	rules;
55 	struct irs_rule *	rule;
56 	struct __res_state *	res;
57 	void 			(*free_res)(void *);
58 };
59 
60 /* Forward */
61 
62 static void		nw_close(struct irs_nw*);
63 static struct nwent *	nw_next(struct irs_nw *);
64 static struct nwent *	nw_byname(struct irs_nw *, const char *, int);
65 static struct nwent *	nw_byaddr(struct irs_nw *, void *, int, int);
66 static void    		nw_rewind(struct irs_nw *);
67 static void		nw_minimize(struct irs_nw *);
68 static struct __res_state * nw_res_get(struct irs_nw *this);
69 static void		nw_res_set(struct irs_nw *this,
70 				   struct __res_state *res,
71 				   void (*free_res)(void *));
72 
73 static int		init(struct irs_nw *this);
74 
75 /* Public */
76 
77 struct irs_nw *
78 irs_gen_nw(struct irs_acc *this) {
79 	struct gen_p *accpvt = (struct gen_p *)this->private;
80 	struct irs_nw *nw;
81 	struct pvt *pvt;
82 
83 	if (!(pvt = memget(sizeof *pvt))) {
84 		errno = ENOMEM;
85 		return (NULL);
86 	}
87 	memset(pvt, 0, sizeof *pvt);
88 	if (!(nw = memget(sizeof *nw))) {
89 		memput(pvt, sizeof *pvt);
90 		errno = ENOMEM;
91 		return (NULL);
92 	}
93 	memset(nw, 0x5e, sizeof *nw);
94 	pvt->rules = accpvt->map_rules[irs_nw];
95 	pvt->rule = pvt->rules;
96 	nw->private = pvt;
97 	nw->close = nw_close;
98 	nw->next = nw_next;
99 	nw->byname = nw_byname;
100 	nw->byaddr = nw_byaddr;
101 	nw->rewind = nw_rewind;
102 	nw->minimize = nw_minimize;
103 	nw->res_get = nw_res_get;
104 	nw->res_set = nw_res_set;
105 	return (nw);
106 }
107 
108 /* Methods */
109 
110 static void
111 nw_close(struct irs_nw *this) {
112 	struct pvt *pvt = (struct pvt *)this->private;
113 
114 	nw_minimize(this);
115 
116 	if (pvt->res && pvt->free_res)
117 		(*pvt->free_res)(pvt->res);
118 
119 	memput(pvt, sizeof *pvt);
120 	memput(this, sizeof *this);
121 }
122 
123 static struct nwent *
124 nw_next(struct irs_nw *this) {
125 	struct pvt *pvt = (struct pvt *)this->private;
126 	struct nwent *rval;
127 	struct irs_nw *nw;
128 
129 	if (init(this) == -1)
130 		return(NULL);
131 
132 	while (pvt->rule) {
133 		nw = pvt->rule->inst->nw;
134 		rval = (*nw->next)(nw);
135 		if (rval)
136 			return (rval);
137 		if (!(pvt->rules->flags & IRS_CONTINUE))
138 			break;
139 		pvt->rule = pvt->rule->next;
140 		if (pvt->rule) {
141 			nw = pvt->rule->inst->nw;
142 			(*nw->rewind)(nw);
143 		}
144 	}
145 	return (NULL);
146 }
147 
148 static struct nwent *
149 nw_byname(struct irs_nw *this, const char *name, int type) {
150 	struct pvt *pvt = (struct pvt *)this->private;
151 	struct irs_rule *rule;
152 	struct nwent *rval;
153 	struct irs_nw *nw;
154 
155 	if (init(this) == -1)
156 		return(NULL);
157 
158 	for (rule = pvt->rules; rule; rule = rule->next) {
159 		nw = rule->inst->nw;
160 		RES_SET_H_ERRNO(pvt->res, NETDB_INTERNAL);
161 		rval = (*nw->byname)(nw, name, type);
162 		if (rval != NULL)
163 			return (rval);
164 		if (pvt->res->res_h_errno != TRY_AGAIN &&
165 		    !(rule->flags & IRS_CONTINUE))
166 			break;
167 	}
168 	return (NULL);
169 }
170 
171 static struct nwent *
172 nw_byaddr(struct irs_nw *this, void *net, int length, int type) {
173 	struct pvt *pvt = (struct pvt *)this->private;
174 	struct irs_rule *rule;
175 	struct nwent *rval;
176 	struct irs_nw *nw;
177 
178 	if (init(this) == -1)
179 		return(NULL);
180 
181 	for (rule = pvt->rules; rule; rule = rule->next) {
182 		nw = rule->inst->nw;
183 		RES_SET_H_ERRNO(pvt->res, NETDB_INTERNAL);
184 		rval = (*nw->byaddr)(nw, net, length, type);
185 		if (rval != NULL)
186 			return (rval);
187 		if (pvt->res->res_h_errno != TRY_AGAIN &&
188 		    !(rule->flags & IRS_CONTINUE))
189 			break;
190 	}
191 	return (NULL);
192 }
193 
194 static void
195 nw_rewind(struct irs_nw *this) {
196 	struct pvt *pvt = (struct pvt *)this->private;
197 	struct irs_nw *nw;
198 
199 	pvt->rule = pvt->rules;
200 	if (pvt->rule) {
201 		nw = pvt->rule->inst->nw;
202 		(*nw->rewind)(nw);
203 	}
204 }
205 
206 static void
207 nw_minimize(struct irs_nw *this) {
208 	struct pvt *pvt = (struct pvt *)this->private;
209 	struct irs_rule *rule;
210 
211 	if (pvt->res)
212 		res_nclose(pvt->res);
213 	for (rule = pvt->rules; rule != NULL; rule = rule->next) {
214 		struct irs_nw *nw = rule->inst->nw;
215 
216 		(*nw->minimize)(nw);
217 	}
218 }
219 
220 static struct __res_state *
221 nw_res_get(struct irs_nw *this) {
222 	struct pvt *pvt = (struct pvt *)this->private;
223 
224 	if (!pvt->res) {
225 		struct __res_state *res;
226 		res = (struct __res_state *)malloc(sizeof *res);
227 		if (!res) {
228 			errno = ENOMEM;
229 			return (NULL);
230 		}
231 		memset(res, 0, sizeof *res);
232 		nw_res_set(this, res, free);
233 	}
234 
235 	return (pvt->res);
236 }
237 
238 static void
239 nw_res_set(struct irs_nw *this, struct __res_state *res,
240 		void (*free_res)(void *)) {
241 	struct pvt *pvt = (struct pvt *)this->private;
242 	struct irs_rule *rule;
243 
244 	if (pvt->res && pvt->free_res) {
245 		res_nclose(pvt->res);
246 		(*pvt->free_res)(pvt->res);
247 	}
248 
249 	pvt->res = res;
250 	pvt->free_res = free_res;
251 
252 	for (rule = pvt->rules; rule != NULL; rule = rule->next) {
253 		struct irs_nw *nw = rule->inst->nw;
254 
255 		(*nw->res_set)(nw, pvt->res, NULL);
256 	}
257 }
258 
259 static int
260 init(struct irs_nw *this) {
261 	struct pvt *pvt = (struct pvt *)this->private;
262 
263 	if (!pvt->res && !nw_res_get(this))
264 		return (-1);
265 	if (((pvt->res->options & RES_INIT) == 0) &&
266 	    res_ninit(pvt->res) == -1)
267 		return (-1);
268 	return (0);
269 }
270