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 #include <netinet/in.h>
24 #include <arpa/nameser.h>
25 #include <resolv.h>
26 
27 #include <stdio.h>
28 #include <string.h>
29 #include <netdb.h>
30 #include <ctype.h>
31 #include <stdlib.h>
32 #include <errno.h>
33 
34 #include <isc/memcluster.h>
35 #include <irs.h>
36 
37 #include "port_after.h"
38 
39 #include "irs_p.h"
40 #include "hesiod.h"
41 #include "dns_p.h"
42 
43 /* Types. */
44 
45 struct pvt {
46 	struct dns_p *		dns;
47 	struct protoent		proto;
48 	char *			prbuf;
49 };
50 
51 /* Forward. */
52 
53 static void 			pr_close(struct irs_pr *);
54 static struct protoent *	pr_byname(struct irs_pr *, const char *);
55 static struct protoent *	pr_bynumber(struct irs_pr *, int);
56 static struct protoent *	pr_next(struct irs_pr *);
57 static void			pr_rewind(struct irs_pr *);
58 static void			pr_minimize(struct irs_pr *);
59 static struct __res_state *	pr_res_get(struct irs_pr *);
60 static void			pr_res_set(struct irs_pr *,
61 					   struct __res_state *,
62 					   void (*)(void *));
63 
64 static struct protoent *	parse_hes_list(struct irs_pr *, char **);
65 
66 /* Public. */
67 
68 struct irs_pr *
69 irs_dns_pr(struct irs_acc *this) {
70 	struct dns_p *dns = (struct dns_p *)this->private;
71 	struct pvt *pvt;
72 	struct irs_pr *pr;
73 
74 	if (!dns->hes_ctx) {
75 		errno = ENODEV;
76 		return (NULL);
77 	}
78 	if (!(pvt = memget(sizeof *pvt))) {
79 		errno = ENOMEM;
80 		return (NULL);
81 	}
82 	memset(pvt, 0, sizeof *pvt);
83 	if (!(pr = memget(sizeof *pr))) {
84 		memput(pvt, sizeof *pvt);
85 		errno = ENOMEM;
86 		return (NULL);
87 	}
88 	memset(pr, 0x5e, sizeof *pr);
89 	pvt->dns = dns;
90 	pr->private = pvt;
91 	pr->byname = pr_byname;
92 	pr->bynumber = pr_bynumber;
93 	pr->next = pr_next;
94 	pr->rewind = pr_rewind;
95 	pr->close = pr_close;
96 	pr->minimize = pr_minimize;
97 	pr->res_get = pr_res_get;
98 	pr->res_set = pr_res_set;
99 	return (pr);
100 }
101 
102 /* Methods. */
103 
104 static void
105 pr_close(struct irs_pr *this) {
106 	struct pvt *pvt = (struct pvt *)this->private;
107 
108 	if (pvt->proto.p_aliases)
109 		free(pvt->proto.p_aliases);
110 	if (pvt->prbuf)
111 		free(pvt->prbuf);
112 
113 	memput(pvt, sizeof *pvt);
114 	memput(this, sizeof *this);
115 }
116 
117 static struct protoent *
118 pr_byname(struct irs_pr *this, const char *name) {
119 	struct pvt *pvt = (struct pvt *)this->private;
120 	struct dns_p *dns = pvt->dns;
121 	struct protoent *proto;
122 	char **hes_list;
123 
124 	if (!(hes_list = hesiod_resolve(dns->hes_ctx, name, "protocol")))
125 		return (NULL);
126 
127 	proto = parse_hes_list(this, hes_list);
128 	hesiod_free_list(dns->hes_ctx, hes_list);
129 	return (proto);
130 }
131 
132 static struct protoent *
133 pr_bynumber(struct irs_pr *this, int num) {
134 	struct pvt *pvt = (struct pvt *)this->private;
135 	struct dns_p *dns = pvt->dns;
136 	struct protoent *proto;
137 	char numstr[16];
138 	char **hes_list;
139 
140 	sprintf(numstr, "%d", num);
141 	if (!(hes_list = hesiod_resolve(dns->hes_ctx, numstr, "protonum")))
142 		return (NULL);
143 
144 	proto = parse_hes_list(this, hes_list);
145 	hesiod_free_list(dns->hes_ctx, hes_list);
146 	return (proto);
147 }
148 
149 static struct protoent *
150 pr_next(struct irs_pr *this) {
151 	UNUSED(this);
152 	errno = ENODEV;
153 	return (NULL);
154 }
155 
156 static void
157 pr_rewind(struct irs_pr *this) {
158 	UNUSED(this);
159 	/* NOOP */
160 }
161 
162 static void
163 pr_minimize(struct irs_pr *this) {
164 	UNUSED(this);
165 	/* NOOP */
166 }
167 
168 static struct __res_state *
169 pr_res_get(struct irs_pr *this) {
170 	struct pvt *pvt = (struct pvt *)this->private;
171 	struct dns_p *dns = pvt->dns;
172 
173 	return (__hesiod_res_get(dns->hes_ctx));
174 }
175 
176 static void
177 pr_res_set(struct irs_pr *this, struct __res_state * res,
178 	   void (*free_res)(void *)) {
179 	struct pvt *pvt = (struct pvt *)this->private;
180 	struct dns_p *dns = pvt->dns;
181 
182 	__hesiod_res_set(dns->hes_ctx, res, free_res);
183 }
184 
185 /* Private. */
186 
187 static struct protoent *
188 parse_hes_list(struct irs_pr *this, char **hes_list) {
189 	struct pvt *pvt = (struct pvt *)this->private;
190 	char *p, *cp, **cpp, **new;
191 	int num = 0;
192 	int max = 0;
193 
194 	for (cpp = hes_list; *cpp; cpp++) {
195 		cp = *cpp;
196 
197 		/* Strip away comments, if any. */
198 		if ((p = strchr(cp, '#')))
199 			*p = 0;
200 
201 		/* Skip blank lines. */
202 		p = cp;
203 		while (*p && !isspace((unsigned char)*p))
204 			p++;
205 		if (!*p)
206 			continue;
207 
208 		/* OK, we've got a live one.  Let's parse it for real. */
209 		if (pvt->prbuf)
210 			free(pvt->prbuf);
211 		pvt->prbuf = strdup(cp);
212 
213 		p = pvt->prbuf;
214 		pvt->proto.p_name = p;
215 		while (*p && !isspace((unsigned char)*p))
216 			p++;
217 		if (!*p)
218 			continue;
219 		*p++ = '\0';
220 
221 		pvt->proto.p_proto = atoi(p);
222 		while (*p && !isspace((unsigned char)*p))
223 			p++;
224 		if (*p)
225 			*p++ = '\0';
226 
227 		while (*p) {
228 			if ((num + 1) >= max || !pvt->proto.p_aliases) {
229 				max += 10;
230 				new = realloc(pvt->proto.p_aliases,
231 					      max * sizeof(char *));
232 				if (!new) {
233 					errno = ENOMEM;
234 					goto cleanup;
235 				}
236 				pvt->proto.p_aliases = new;
237 			}
238 			pvt->proto.p_aliases[num++] = p;
239 			while (*p && !isspace((unsigned char)*p))
240 				p++;
241 			if (*p)
242 				*p++ = '\0';
243 		}
244 		if (!pvt->proto.p_aliases)
245 			pvt->proto.p_aliases = malloc(sizeof(char *));
246 		if (!pvt->proto.p_aliases)
247 			goto cleanup;
248 		pvt->proto.p_aliases[num] = NULL;
249 		return (&pvt->proto);
250 	}
251 
252  cleanup:
253 	if (pvt->proto.p_aliases) {
254 		free(pvt->proto.p_aliases);
255 		pvt->proto.p_aliases = NULL;
256 	}
257 	if (pvt->prbuf) {
258 		free(pvt->prbuf);
259 		pvt->prbuf = NULL;
260 	}
261 	return (NULL);
262 }
263 
264 /*! \file */
265