xref: /openbsd/lib/libc/yp/ypmatch_cache.c (revision 5af055cd)
1 /*	$OpenBSD: ypmatch_cache.c,v 1.17 2015/09/13 20:57:28 guenther Exp $ */
2 /*
3  * Copyright (c) 1992, 1993 Theo de Raadt <deraadt@theos.com>
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS
16  * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
17  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
19  * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25  * SUCH DAMAGE.
26  */
27 
28 #include <sys/types.h>
29 #include <stdlib.h>
30 #include <string.h>
31 #include <limits.h>
32 #include <rpc/rpc.h>
33 #include <rpc/xdr.h>
34 #include <rpcsvc/yp.h>
35 #include <rpcsvc/ypclnt.h>
36 #include "ypinternal.h"
37 
38 #ifdef YPMATCHCACHE
39 static bool_t ypmatch_add(const char *, const char *, u_int, char *, u_int);
40 static bool_t ypmatch_find(const char *, const char *, u_int, char **, u_int *);
41 
42 static struct ypmatch_ent {
43 	struct ypmatch_ent	*next;
44 	char			*map, *key;
45 	char			*val;
46 	int			 keylen, vallen;
47 	time_t			 expire_t;
48 } *ypmc;
49 
50 int _yplib_cache = 5;
51 
52 static bool_t
53 ypmatch_add(const char *map, const char *key, u_int keylen, char *val,
54     u_int vallen)
55 {
56 	struct ypmatch_ent *ep;
57 	char *newmap = NULL, *newkey = NULL, *newval = NULL;
58 	time_t t;
59 
60 	if (keylen == 0 || vallen == 0)
61 		return (0);
62 
63 	(void)time(&t);
64 
65 	/* Allocate all required memory first. */
66 	if ((newmap = strdup(map)) == NULL ||
67 	    (newkey = malloc(keylen)) == NULL ||
68 	    (newval = malloc(vallen)) == NULL) {
69 		free(newkey);
70 		free(newmap);
71 		return 0;
72 	}
73 
74 	for (ep = ypmc; ep; ep = ep->next)
75 		if (ep->expire_t < t)
76 			break;
77 
78 	if (ep == NULL) {
79 		/* No expired node, create a new one. */
80 		if ((ep = malloc(sizeof *ep)) == NULL) {
81 			free(newval);
82 			free(newkey);
83 			free(newmap);
84 			return 0;
85 		}
86 		ep->next = ypmc;
87 		ypmc = ep;
88 	} else {
89 		/* Reuse the first expired node from the list. */
90 		free(ep->val);
91 		free(ep->key);
92 		free(ep->map);
93 	}
94 
95 	/* Now we have all the memory we need, copy the data in. */
96 	(void)memcpy(newkey, key, keylen);
97 	(void)memcpy(newval, val, vallen);
98 	ep->map = newmap;
99 	ep->key = newkey;
100 	ep->val = newval;
101 	ep->keylen = keylen;
102 	ep->vallen = vallen;
103 	ep->expire_t = t + _yplib_cache;
104 	return 1;
105 }
106 
107 static bool_t
108 ypmatch_find(const char *map, const char *key, u_int keylen, char **val,
109     u_int *vallen)
110 {
111 	struct ypmatch_ent *ep;
112 	time_t          t;
113 
114 	if (ypmc == NULL)
115 		return 0;
116 
117 	(void) time(&t);
118 
119 	for (ep = ypmc; ep; ep = ep->next) {
120 		if (ep->keylen != keylen)
121 			continue;
122 		if (strcmp(ep->map, map))
123 			continue;
124 		if (memcmp(ep->key, key, keylen))
125 			continue;
126 		if (t > ep->expire_t)
127 			continue;
128 
129 		*val = ep->val;
130 		*vallen = ep->vallen;
131 		return 1;
132 	}
133 	return 0;
134 }
135 #endif
136 
137 int
138 yp_match(const char *indomain, const char *inmap, const char *inkey,
139     int inkeylen, char **outval, int *outvallen)
140 {
141 	struct dom_binding *ysd;
142 	struct ypresp_val yprv;
143 	struct timeval  tv;
144 	struct ypreq_key yprk;
145 	int tries = 0, r;
146 
147 	if (indomain == NULL || *indomain == '\0' ||
148 	    strlen(indomain) > YPMAXDOMAIN || inmap == NULL ||
149 	    *inmap == '\0' || strlen(inmap) > YPMAXMAP ||
150 	    inkey == NULL || inkeylen == 0 || inkeylen >= YPMAXRECORD)
151 		return YPERR_BADARGS;
152 
153 	*outval = NULL;
154 	*outvallen = 0;
155 
156 again:
157 	if (_yp_dobind(indomain, &ysd) != 0)
158 		return YPERR_DOMAIN;
159 
160 #ifdef YPMATCHCACHE
161 	if (!strcmp(_yp_domain, indomain) && ypmatch_find(inmap, inkey,
162 	    inkeylen, &yprv.val.valdat_val, &yprv.val.valdat_len)) {
163 		*outvallen = yprv.val.valdat_len;
164 		if ((*outval = malloc(*outvallen + 1)) == NULL) {
165 			_yp_unbind(ysd);
166 			return YPERR_RESRC;
167 		}
168 		(void)memcpy(*outval, yprv.val.valdat_val, *outvallen);
169 		(*outval)[*outvallen] = '\0';
170 		_yp_unbind(ysd);
171 		return 0;
172 	}
173 #endif
174 
175 	tv.tv_sec = _yplib_timeout;
176 	tv.tv_usec = 0;
177 
178 	yprk.domain = (char *)indomain;
179 	yprk.map = (char *)inmap;
180 	yprk.key.keydat_val = (char *) inkey;
181 	yprk.key.keydat_len = inkeylen;
182 
183 	memset(&yprv, 0, sizeof yprv);
184 
185 	r = clnt_call(ysd->dom_client, YPPROC_MATCH,
186 	    xdr_ypreq_key, &yprk, xdr_ypresp_val, &yprv, tv);
187 	if (r != RPC_SUCCESS) {
188 		if (tries++)
189 			clnt_perror(ysd->dom_client, "yp_match: clnt_call");
190 		ysd->dom_vers = -1;
191 		goto again;
192 	}
193 	if (!(r = ypprot_err(yprv.stat))) {
194 		*outvallen = yprv.val.valdat_len;
195 		if ((*outval = malloc(*outvallen + 1)) == NULL) {
196 			r = YPERR_RESRC;
197 			goto out;
198 		}
199 		(void)memcpy(*outval, yprv.val.valdat_val, *outvallen);
200 		(*outval)[*outvallen] = '\0';
201 #ifdef YPMATCHCACHE
202 		if (strcmp(_yp_domain, indomain) == 0)
203 			(void)ypmatch_add(inmap, inkey, inkeylen,
204 			    *outval, *outvallen);
205 #endif
206 	}
207 out:
208 	xdr_free(xdr_ypresp_val, (char *) &yprv);
209 	_yp_unbind(ysd);
210 	return r;
211 }
212 DEF_WEAK(yp_match);
213 
214 int
215 yp_next(const char *indomain, const char *inmap, const char *inkey,
216     int inkeylen, char **outkey, int *outkeylen, char **outval, int *outvallen)
217 {
218 	struct ypresp_key_val yprkv;
219 	struct ypreq_key yprk;
220 	struct dom_binding *ysd;
221 	struct timeval  tv;
222 	int tries = 0, r;
223 
224 	if (indomain == NULL || *indomain == '\0' ||
225 	    strlen(indomain) > YPMAXDOMAIN || inmap == NULL ||
226 	    *inmap == '\0' || strlen(inmap) > YPMAXMAP ||
227 	    inkeylen == 0 || inkeylen >= YPMAXRECORD)
228 		return YPERR_BADARGS;
229 
230 	*outkey = *outval = NULL;
231 	*outkeylen = *outvallen = 0;
232 
233 again:
234 	if (_yp_dobind(indomain, &ysd) != 0)
235 		return YPERR_DOMAIN;
236 
237 	tv.tv_sec = _yplib_timeout;
238 	tv.tv_usec = 0;
239 
240 	yprk.domain = (char *)indomain;
241 	yprk.map = (char *)inmap;
242 	yprk.key.keydat_val = (char *)inkey;
243 	yprk.key.keydat_len = inkeylen;
244 	(void)memset(&yprkv, 0, sizeof yprkv);
245 
246 	r = clnt_call(ysd->dom_client, YPPROC_NEXT,
247 	    xdr_ypreq_key, &yprk, xdr_ypresp_key_val, &yprkv, tv);
248 	if (r != RPC_SUCCESS) {
249 		if (tries++)
250 			clnt_perror(ysd->dom_client, "yp_next: clnt_call");
251 		ysd->dom_vers = -1;
252 		goto again;
253 	}
254 	if (!(r = ypprot_err(yprkv.stat))) {
255 		*outkeylen = yprkv.key.keydat_len;
256 		*outvallen = yprkv.val.valdat_len;
257 		if ((*outkey = malloc(*outkeylen + 1)) == NULL ||
258 		    (*outval = malloc(*outvallen + 1)) == NULL) {
259 			free(*outkey);
260 			r = YPERR_RESRC;
261 		} else {
262 			(void)memcpy(*outkey, yprkv.key.keydat_val, *outkeylen);
263 			(*outkey)[*outkeylen] = '\0';
264 			(void)memcpy(*outval, yprkv.val.valdat_val, *outvallen);
265 			(*outval)[*outvallen] = '\0';
266 		}
267 	}
268 	xdr_free(xdr_ypresp_key_val, (char *) &yprkv);
269 	_yp_unbind(ysd);
270 	return r;
271 }
272 DEF_WEAK(yp_next);
273