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 #if defined(LIBC_SCCS) && !defined(lint)
19 static const char rcsid[] = "$Id: dns_sv.c,v 1.5 2005/04/27 04:56:23 sra Exp $";
20 #endif
21
22 /* Imports */
23
24 #include "port_before.h"
25
26 #include <sys/types.h>
27 #include <netinet/in.h>
28
29 #include <stdio.h>
30 #include <string.h>
31 #include <netdb.h>
32 #include <ctype.h>
33 #include <stdlib.h>
34 #include <errno.h>
35
36 #include <sys/types.h>
37 #include <netinet/in.h>
38 #include <arpa/nameser.h>
39 #include <resolv.h>
40
41 #include <isc/memcluster.h>
42 #include <irs.h>
43
44 #include "port_after.h"
45
46 #include "irs_p.h"
47 #include "hesiod.h"
48 #include "dns_p.h"
49
50 /* Definitions */
51
52 struct pvt {
53 struct dns_p * dns;
54 struct servent serv;
55 char * svbuf;
56 struct __res_state * res;
57 void (*free_res)(void *);
58 };
59
60 /* Forward. */
61
62 static void sv_close(struct irs_sv *);
63 static struct servent * sv_byname(struct irs_sv *,
64 const char *, const char *);
65 static struct servent * sv_byport(struct irs_sv *, int, const char *);
66 static struct servent * sv_next(struct irs_sv *);
67 static void sv_rewind(struct irs_sv *);
68 static void sv_minimize(struct irs_sv *);
69 #ifdef SV_RES_SETGET
70 static struct __res_state * sv_res_get(struct irs_sv *);
71 static void sv_res_set(struct irs_sv *,
72 struct __res_state *,
73 void (*)(void *));
74 #endif
75
76 static struct servent * parse_hes_list(struct irs_sv *,
77 char **, const char *);
78
79 /* Public */
80
81 struct irs_sv *
irs_dns_sv(struct irs_acc * this)82 irs_dns_sv(struct irs_acc *this) {
83 struct dns_p *dns = (struct dns_p *)this->private;
84 struct irs_sv *sv;
85 struct pvt *pvt;
86
87 if (!dns || !dns->hes_ctx) {
88 errno = ENODEV;
89 return (NULL);
90 }
91 if (!(pvt = memget(sizeof *pvt))) {
92 errno = ENOMEM;
93 return (NULL);
94 }
95 memset(pvt, 0, sizeof *pvt);
96 pvt->dns = dns;
97 if (!(sv = memget(sizeof *sv))) {
98 memput(pvt, sizeof *pvt);
99 errno = ENOMEM;
100 return (NULL);
101 }
102 memset(sv, 0x5e, sizeof *sv);
103 sv->private = pvt;
104 sv->byname = sv_byname;
105 sv->byport = sv_byport;
106 sv->next = sv_next;
107 sv->rewind = sv_rewind;
108 sv->close = sv_close;
109 sv->minimize = sv_minimize;
110 #ifdef SV_RES_SETGET
111 sv->res_get = sv_res_get;
112 sv->res_set = sv_res_set;
113 #else
114 sv->res_get = NULL; /*%< sv_res_get; */
115 sv->res_set = NULL; /*%< sv_res_set; */
116 #endif
117 return (sv);
118 }
119
120 /* Methods */
121
122 static void
sv_close(struct irs_sv * this)123 sv_close(struct irs_sv *this) {
124 struct pvt *pvt = (struct pvt *)this->private;
125
126 if (pvt->serv.s_aliases)
127 free(pvt->serv.s_aliases);
128 if (pvt->svbuf)
129 free(pvt->svbuf);
130
131 if (pvt->res && pvt->free_res)
132 (*pvt->free_res)(pvt->res);
133 memput(pvt, sizeof *pvt);
134 memput(this, sizeof *this);
135 }
136
137 static struct servent *
sv_byname(struct irs_sv * this,const char * name,const char * proto)138 sv_byname(struct irs_sv *this, const char *name, const char *proto) {
139 struct pvt *pvt = (struct pvt *)this->private;
140 struct dns_p *dns = pvt->dns;
141 struct servent *s;
142 char **hes_list;
143
144 if (!(hes_list = hesiod_resolve(dns->hes_ctx, name, "service")))
145 return (NULL);
146
147 s = parse_hes_list(this, hes_list, proto);
148 hesiod_free_list(dns->hes_ctx, hes_list);
149 return (s);
150 }
151
152 static struct servent *
sv_byport(struct irs_sv * this,int port,const char * proto)153 sv_byport(struct irs_sv *this, int port, const char *proto) {
154 struct pvt *pvt = (struct pvt *)this->private;
155 struct dns_p *dns = pvt->dns;
156 struct servent *s;
157 char portstr[16];
158 char **hes_list;
159
160 sprintf(portstr, "%d", ntohs(port));
161 if (!(hes_list = hesiod_resolve(dns->hes_ctx, portstr, "port")))
162 return (NULL);
163
164 s = parse_hes_list(this, hes_list, proto);
165 hesiod_free_list(dns->hes_ctx, hes_list);
166 return (s);
167 }
168
169 static struct servent *
sv_next(struct irs_sv * this)170 sv_next(struct irs_sv *this) {
171 UNUSED(this);
172 errno = ENODEV;
173 return (NULL);
174 }
175
176 static void
sv_rewind(struct irs_sv * this)177 sv_rewind(struct irs_sv *this) {
178 UNUSED(this);
179 /* NOOP */
180 }
181
182 /* Private */
183
184 static struct servent *
parse_hes_list(struct irs_sv * this,char ** hes_list,const char * proto)185 parse_hes_list(struct irs_sv *this, char **hes_list, const char *proto) {
186 struct pvt *pvt = (struct pvt *)this->private;
187 char *p, *cp, **cpp, **new;
188 int proto_len;
189 int num = 0;
190 int max = 0;
191
192 for (cpp = hes_list; *cpp; cpp++) {
193 cp = *cpp;
194
195 /* Strip away comments, if any. */
196 if ((p = strchr(cp, '#')))
197 *p = 0;
198
199 /* Check to make sure the protocol matches. */
200 p = cp;
201 while (*p && !isspace((unsigned char)*p))
202 p++;
203 if (!*p)
204 continue;
205 if (proto) {
206 proto_len = strlen(proto);
207 if (strncasecmp(++p, proto, proto_len) != 0)
208 continue;
209 if (p[proto_len] && !isspace(p[proto_len]&0xff))
210 continue;
211 }
212 /* OK, we've got a live one. Let's parse it for real. */
213 if (pvt->svbuf)
214 free(pvt->svbuf);
215 pvt->svbuf = strdup(cp);
216
217 p = pvt->svbuf;
218 pvt->serv.s_name = p;
219 while (*p && !isspace(*p&0xff))
220 p++;
221 if (!*p)
222 continue;
223 *p++ = '\0';
224
225 pvt->serv.s_proto = p;
226 while (*p && !isspace(*p&0xff))
227 p++;
228 if (!*p)
229 continue;
230 *p++ = '\0';
231
232 pvt->serv.s_port = htons((u_short) atoi(p));
233 while (*p && !isspace(*p&0xff))
234 p++;
235 if (*p)
236 *p++ = '\0';
237
238 while (*p) {
239 if ((num + 1) >= max || !pvt->serv.s_aliases) {
240 max += 10;
241 new = realloc(pvt->serv.s_aliases,
242 max * sizeof(char *));
243 if (!new) {
244 errno = ENOMEM;
245 goto cleanup;
246 }
247 pvt->serv.s_aliases = new;
248 }
249 pvt->serv.s_aliases[num++] = p;
250 while (*p && !isspace(*p&0xff))
251 p++;
252 if (*p)
253 *p++ = '\0';
254 }
255 if (!pvt->serv.s_aliases)
256 pvt->serv.s_aliases = malloc(sizeof(char *));
257 if (!pvt->serv.s_aliases)
258 goto cleanup;
259 pvt->serv.s_aliases[num] = NULL;
260 return (&pvt->serv);
261 }
262
263 cleanup:
264 if (pvt->serv.s_aliases) {
265 free(pvt->serv.s_aliases);
266 pvt->serv.s_aliases = NULL;
267 }
268 if (pvt->svbuf) {
269 free(pvt->svbuf);
270 pvt->svbuf = NULL;
271 }
272 return (NULL);
273 }
274
275 static void
sv_minimize(struct irs_sv * this)276 sv_minimize(struct irs_sv *this) {
277 UNUSED(this);
278 /* NOOP */
279 }
280
281 #ifdef SV_RES_SETGET
282 static struct __res_state *
sv_res_get(struct irs_sv * this)283 sv_res_get(struct irs_sv *this) {
284 struct pvt *pvt = (struct pvt *)this->private;
285 struct dns_p *dns = pvt->dns;
286
287 return (__hesiod_res_get(dns->hes_ctx));
288 }
289
290 static void
sv_res_set(struct irs_sv * this,struct __res_state * res,void (* free_res)(void *))291 sv_res_set(struct irs_sv *this, struct __res_state * res,
292 void (*free_res)(void *)) {
293 struct pvt *pvt = (struct pvt *)this->private;
294 struct dns_p *dns = pvt->dns;
295
296 __hesiod_res_set(dns->hes_ctx, res, free_res);
297 }
298 #endif
299
300 /*! \file */
301