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_pr.c,v 1.5 2005/04/27 04:56:22 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 #include <arpa/nameser.h>
29 #include <resolv.h>
30
31 #include <stdio.h>
32 #include <string.h>
33 #include <netdb.h>
34 #include <ctype.h>
35 #include <stdlib.h>
36 #include <errno.h>
37
38 #include <isc/memcluster.h>
39 #include <irs.h>
40
41 #include "port_after.h"
42
43 #include "irs_p.h"
44 #include "hesiod.h"
45 #include "dns_p.h"
46
47 /* Types. */
48
49 struct pvt {
50 struct dns_p * dns;
51 struct protoent proto;
52 char * prbuf;
53 };
54
55 /* Forward. */
56
57 static void pr_close(struct irs_pr *);
58 static struct protoent * pr_byname(struct irs_pr *, const char *);
59 static struct protoent * pr_bynumber(struct irs_pr *, int);
60 static struct protoent * pr_next(struct irs_pr *);
61 static void pr_rewind(struct irs_pr *);
62 static void pr_minimize(struct irs_pr *);
63 static struct __res_state * pr_res_get(struct irs_pr *);
64 static void pr_res_set(struct irs_pr *,
65 struct __res_state *,
66 void (*)(void *));
67
68 static struct protoent * parse_hes_list(struct irs_pr *, char **);
69
70 /* Public. */
71
72 struct irs_pr *
irs_dns_pr(struct irs_acc * this)73 irs_dns_pr(struct irs_acc *this) {
74 struct dns_p *dns = (struct dns_p *)this->private;
75 struct pvt *pvt;
76 struct irs_pr *pr;
77
78 if (!dns->hes_ctx) {
79 errno = ENODEV;
80 return (NULL);
81 }
82 if (!(pvt = memget(sizeof *pvt))) {
83 errno = ENOMEM;
84 return (NULL);
85 }
86 memset(pvt, 0, sizeof *pvt);
87 if (!(pr = memget(sizeof *pr))) {
88 memput(pvt, sizeof *pvt);
89 errno = ENOMEM;
90 return (NULL);
91 }
92 memset(pr, 0x5e, sizeof *pr);
93 pvt->dns = dns;
94 pr->private = pvt;
95 pr->byname = pr_byname;
96 pr->bynumber = pr_bynumber;
97 pr->next = pr_next;
98 pr->rewind = pr_rewind;
99 pr->close = pr_close;
100 pr->minimize = pr_minimize;
101 pr->res_get = pr_res_get;
102 pr->res_set = pr_res_set;
103 return (pr);
104 }
105
106 /* Methods. */
107
108 static void
pr_close(struct irs_pr * this)109 pr_close(struct irs_pr *this) {
110 struct pvt *pvt = (struct pvt *)this->private;
111
112 if (pvt->proto.p_aliases)
113 free(pvt->proto.p_aliases);
114 if (pvt->prbuf)
115 free(pvt->prbuf);
116
117 memput(pvt, sizeof *pvt);
118 memput(this, sizeof *this);
119 }
120
121 static struct protoent *
pr_byname(struct irs_pr * this,const char * name)122 pr_byname(struct irs_pr *this, const char *name) {
123 struct pvt *pvt = (struct pvt *)this->private;
124 struct dns_p *dns = pvt->dns;
125 struct protoent *proto;
126 char **hes_list;
127
128 if (!(hes_list = hesiod_resolve(dns->hes_ctx, name, "protocol")))
129 return (NULL);
130
131 proto = parse_hes_list(this, hes_list);
132 hesiod_free_list(dns->hes_ctx, hes_list);
133 return (proto);
134 }
135
136 static struct protoent *
pr_bynumber(struct irs_pr * this,int num)137 pr_bynumber(struct irs_pr *this, int num) {
138 struct pvt *pvt = (struct pvt *)this->private;
139 struct dns_p *dns = pvt->dns;
140 struct protoent *proto;
141 char numstr[16];
142 char **hes_list;
143
144 sprintf(numstr, "%d", num);
145 if (!(hes_list = hesiod_resolve(dns->hes_ctx, numstr, "protonum")))
146 return (NULL);
147
148 proto = parse_hes_list(this, hes_list);
149 hesiod_free_list(dns->hes_ctx, hes_list);
150 return (proto);
151 }
152
153 static struct protoent *
pr_next(struct irs_pr * this)154 pr_next(struct irs_pr *this) {
155 UNUSED(this);
156 errno = ENODEV;
157 return (NULL);
158 }
159
160 static void
pr_rewind(struct irs_pr * this)161 pr_rewind(struct irs_pr *this) {
162 UNUSED(this);
163 /* NOOP */
164 }
165
166 static void
pr_minimize(struct irs_pr * this)167 pr_minimize(struct irs_pr *this) {
168 UNUSED(this);
169 /* NOOP */
170 }
171
172 static struct __res_state *
pr_res_get(struct irs_pr * this)173 pr_res_get(struct irs_pr *this) {
174 struct pvt *pvt = (struct pvt *)this->private;
175 struct dns_p *dns = pvt->dns;
176
177 return (__hesiod_res_get(dns->hes_ctx));
178 }
179
180 static void
pr_res_set(struct irs_pr * this,struct __res_state * res,void (* free_res)(void *))181 pr_res_set(struct irs_pr *this, struct __res_state * res,
182 void (*free_res)(void *)) {
183 struct pvt *pvt = (struct pvt *)this->private;
184 struct dns_p *dns = pvt->dns;
185
186 __hesiod_res_set(dns->hes_ctx, res, free_res);
187 }
188
189 /* Private. */
190
191 static struct protoent *
parse_hes_list(struct irs_pr * this,char ** hes_list)192 parse_hes_list(struct irs_pr *this, char **hes_list) {
193 struct pvt *pvt = (struct pvt *)this->private;
194 char *p, *cp, **cpp, **new;
195 int num = 0;
196 int max = 0;
197
198 for (cpp = hes_list; *cpp; cpp++) {
199 cp = *cpp;
200
201 /* Strip away comments, if any. */
202 if ((p = strchr(cp, '#')))
203 *p = 0;
204
205 /* Skip blank lines. */
206 p = cp;
207 while (*p && !isspace((unsigned char)*p))
208 p++;
209 if (!*p)
210 continue;
211
212 /* OK, we've got a live one. Let's parse it for real. */
213 if (pvt->prbuf)
214 free(pvt->prbuf);
215 pvt->prbuf = strdup(cp);
216
217 p = pvt->prbuf;
218 pvt->proto.p_name = p;
219 while (*p && !isspace((unsigned char)*p))
220 p++;
221 if (!*p)
222 continue;
223 *p++ = '\0';
224
225 pvt->proto.p_proto = atoi(p);
226 while (*p && !isspace((unsigned char)*p))
227 p++;
228 if (*p)
229 *p++ = '\0';
230
231 while (*p) {
232 if ((num + 1) >= max || !pvt->proto.p_aliases) {
233 max += 10;
234 new = realloc(pvt->proto.p_aliases,
235 max * sizeof(char *));
236 if (!new) {
237 errno = ENOMEM;
238 goto cleanup;
239 }
240 pvt->proto.p_aliases = new;
241 }
242 pvt->proto.p_aliases[num++] = p;
243 while (*p && !isspace((unsigned char)*p))
244 p++;
245 if (*p)
246 *p++ = '\0';
247 }
248 if (!pvt->proto.p_aliases)
249 pvt->proto.p_aliases = malloc(sizeof(char *));
250 if (!pvt->proto.p_aliases)
251 goto cleanup;
252 pvt->proto.p_aliases[num] = NULL;
253 return (&pvt->proto);
254 }
255
256 cleanup:
257 if (pvt->proto.p_aliases) {
258 free(pvt->proto.p_aliases);
259 pvt->proto.p_aliases = NULL;
260 }
261 if (pvt->prbuf) {
262 free(pvt->prbuf);
263 pvt->prbuf = NULL;
264 }
265 return (NULL);
266 }
267
268 /*! \file */
269