1 /* $NetBSD: getnetpath.c,v 1.3 2000/07/06 03:10:34 christos Exp $ */
2
3 /*-
4 * Copyright (c) 2009, Sun Microsystems, Inc.
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions are met:
9 * - Redistributions of source code must retain the above copyright notice,
10 * this list of conditions and the following disclaimer.
11 * - Redistributions in binary form must reproduce the above copyright notice,
12 * this list of conditions and the following disclaimer in the documentation
13 * and/or other materials provided with the distribution.
14 * - Neither the name of Sun Microsystems, Inc. nor the names of its
15 * contributors may be used to endorse or promote products derived
16 * from this software without specific prior written permission.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
19 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
22 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
23 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
24 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
25 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
26 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
27 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
28 * POSSIBILITY OF SUCH DAMAGE.
29 */
30
31 #if defined(LIBC_SCCS) && !defined(lint)
32 static char sccsid[] = "@(#)getnetpath.c 1.11 91/12/19 SMI";
33 #endif
34 #include <sys/cdefs.h>
35 __FBSDID("$FreeBSD: stable/9/lib/libc/rpc/getnetpath.c 301821 2016-06-11 01:44:27Z ngie $");
36
37 /*
38 * Copyright (c) 1989 by Sun Microsystems, Inc.
39 */
40
41 #include "namespace.h"
42 #include <stdio.h>
43 #include <errno.h>
44 #include <netconfig.h>
45 #include <stdlib.h>
46 #include <string.h>
47 #include <syslog.h>
48 #include "un-namespace.h"
49
50 /*
51 * internal structure to keep track of a netpath "session"
52 */
53 struct netpath_chain {
54 struct netconfig *ncp; /* an nconf entry */
55 struct netpath_chain *nchain_next; /* next nconf entry allocated */
56 };
57
58
59 struct netpath_vars {
60 int valid; /* token that indicates a valid netpath_vars */
61 void *nc_handlep; /* handle for current netconfig "session" */
62 char *netpath; /* pointer to current view-point in NETPATH */
63 char *netpath_start; /* pointer to start of our copy of NETPATH */
64 struct netpath_chain *ncp_list; /* list of nconfs allocated this session*/
65 };
66
67 #define NP_VALID 0xf00d
68 #define NP_INVALID 0
69
70 char *_get_next_token(char *, int);
71
72
73 /*
74 * A call to setnetpath() establishes a NETPATH "session". setnetpath()
75 * must be called before the first call to getnetpath(). A "handle" is
76 * returned to distinguish the session; this handle should be passed
77 * subsequently to getnetpath(). (Handles are used to allow for nested calls
78 * to setnetpath()).
79 * If setnetpath() is unable to establish a session (due to lack of memory
80 * resources, or the absence of the /etc/netconfig file), a NULL pointer is
81 * returned.
82 */
83
84 void *
setnetpath()85 setnetpath()
86 {
87
88 struct netpath_vars *np_sessionp; /* this session's variables */
89 char *npp; /* NETPATH env variable */
90
91 #ifdef MEM_CHK
92 malloc_debug(1);
93 #endif
94
95 if ((np_sessionp =
96 (struct netpath_vars *)malloc(sizeof (struct netpath_vars))) == NULL) {
97 return (NULL);
98 }
99 if ((np_sessionp->nc_handlep = setnetconfig()) == NULL) {
100 free(np_sessionp);
101 syslog (LOG_ERR, "rpc: failed to open " NETCONFIG);
102 return (NULL);
103 }
104 np_sessionp->valid = NP_VALID;
105 np_sessionp->ncp_list = NULL;
106 if ((npp = getenv(NETPATH)) == NULL) {
107 np_sessionp->netpath = NULL;
108 } else {
109 (void) endnetconfig(np_sessionp->nc_handlep);/* won't need nc session*/
110 np_sessionp->nc_handlep = NULL;
111 if ((np_sessionp->netpath = malloc(strlen(npp)+1)) == NULL)
112 goto failed;
113 else {
114 (void) strcpy(np_sessionp->netpath, npp);
115 }
116 }
117 np_sessionp->netpath_start = np_sessionp->netpath;
118 return ((void *)np_sessionp);
119
120 failed:
121 free(np_sessionp);
122 return (NULL);
123 }
124
125 /*
126 * When first called, getnetpath() returns a pointer to the netconfig
127 * database entry corresponding to the first valid NETPATH component. The
128 * netconfig entry is formatted as a struct netconfig.
129 * On each subsequent call, getnetpath returns a pointer to the netconfig
130 * entry that corresponds to the next valid NETPATH component. getnetpath
131 * can thus be used to search the netconfig database for all networks
132 * included in the NETPATH variable.
133 * When NETPATH has been exhausted, getnetpath() returns NULL. It returns
134 * NULL and sets errno in case of an error (e.g., setnetpath was not called
135 * previously).
136 * getnetpath() silently ignores invalid NETPATH components. A NETPATH
137 * compnent is invalid if there is no corresponding entry in the netconfig
138 * database.
139 * If the NETPATH variable is unset, getnetpath() behaves as if NETPATH
140 * were set to the sequence of default or visible networks in the netconfig
141 * database, in the order in which they are listed.
142 */
143
144 struct netconfig *
getnetpath(handlep)145 getnetpath(handlep)
146 void *handlep;
147 {
148 struct netpath_vars *np_sessionp = (struct netpath_vars *)handlep;
149 struct netconfig *ncp = NULL; /* temp. holds a netconfig session */
150 struct netpath_chain *chainp; /* holds chain of ncp's we alloc */
151 char *npp; /* holds current NETPATH */
152
153 if (np_sessionp == NULL || np_sessionp->valid != NP_VALID) {
154 errno = EINVAL;
155 return (NULL);
156 }
157 if (np_sessionp->netpath_start == NULL) { /* NETPATH was not set */
158 do { /* select next visible network */
159 if (np_sessionp->nc_handlep == NULL) {
160 np_sessionp->nc_handlep = setnetconfig();
161 if (np_sessionp->nc_handlep == NULL)
162 syslog (LOG_ERR, "rpc: failed to open " NETCONFIG);
163 }
164 if ((ncp = getnetconfig(np_sessionp->nc_handlep)) == NULL) {
165 return(NULL);
166 }
167 } while ((ncp->nc_flag & NC_VISIBLE) == 0);
168 return (ncp);
169 }
170 /*
171 * Find first valid network ID in netpath.
172 */
173 while ((npp = np_sessionp->netpath) != NULL && strlen(npp) != 0) {
174 np_sessionp->netpath = _get_next_token(npp, ':');
175 /*
176 * npp is a network identifier.
177 */
178 if ((ncp = getnetconfigent(npp)) != NULL) {
179 chainp = (struct netpath_chain *) /* cobble alloc chain entry */
180 malloc(sizeof (struct netpath_chain));
181 chainp->ncp = ncp;
182 chainp->nchain_next = NULL;
183 if (np_sessionp->ncp_list == NULL) {
184 np_sessionp->ncp_list = chainp;
185 } else {
186 np_sessionp->ncp_list->nchain_next = chainp;
187 }
188 return (ncp);
189 }
190 /* couldn't find this token in the database; go to next one. */
191 }
192 return (NULL);
193 }
194
195 /*
196 * endnetpath() may be called to unbind NETPATH when processing is complete,
197 * releasing resources for reuse. It returns 0 on success and -1 on failure
198 * (e.g. if setnetpath() was not called previously.
199 */
200 int
endnetpath(handlep)201 endnetpath(handlep)
202 void *handlep;
203 {
204 struct netpath_vars *np_sessionp = (struct netpath_vars *)handlep;
205 struct netpath_chain *chainp, *lastp;
206
207 if (np_sessionp == NULL || np_sessionp->valid != NP_VALID) {
208 errno = EINVAL;
209 return (-1);
210 }
211 if (np_sessionp->nc_handlep != NULL)
212 endnetconfig(np_sessionp->nc_handlep);
213 if (np_sessionp->netpath_start != NULL)
214 free(np_sessionp->netpath_start);
215 for (chainp = np_sessionp->ncp_list; chainp != NULL;
216 lastp=chainp, chainp=chainp->nchain_next, free(lastp)) {
217 freenetconfigent(chainp->ncp);
218 }
219 free(np_sessionp);
220 #ifdef MEM_CHK
221 if (malloc_verify() == 0) {
222 fprintf(stderr, "memory heap corrupted in endnetpath\n");
223 exit(1);
224 }
225 #endif
226 return (0);
227 }
228
229
230
231 /*
232 * Returns pointer to the rest-of-the-string after the current token.
233 * The token itself starts at arg, and we null terminate it. We return NULL
234 * if either the arg is empty, or if this is the last token.
235 */
236
237 char *
_get_next_token(npp,token)238 _get_next_token(npp, token)
239 char *npp; /* string */
240 int token; /* char to parse string for */
241 {
242 char *cp; /* char pointer */
243 char *np; /* netpath pointer */
244 char *ep; /* escape pointer */
245
246 if ((cp = strchr(npp, token)) == NULL) {
247 return (NULL);
248 }
249 /*
250 * did find a token, but it might be escaped.
251 */
252 if ((cp > npp) && (cp[-1] == '\\')) {
253 /* if slash was also escaped, carry on, otherwise find next token */
254 if ((cp > npp + 1) && (cp[-2] != '\\')) {
255 /* shift r-o-s onto the escaped token */
256 strcpy(&cp[-1], cp); /* XXX: overlapping string copy */
257 /*
258 * Do a recursive call.
259 * We don't know how many escaped tokens there might be.
260 */
261 return (_get_next_token(cp, token));
262 }
263 }
264
265 *cp++ = '\0'; /* null-terminate token */
266 /* get rid of any backslash escapes */
267 ep = npp;
268 while ((np = strchr(ep, '\\')) != NULL) {
269 if (np[1] == '\\')
270 np++;
271 strcpy(np, (ep = &np[1])); /* XXX: overlapping string copy */
272 }
273 return (cp); /* return ptr to r-o-s */
274 }
275