1 /* $NetBSD: getnetpath.c,v 1.18 2022/01/04 22:10:08 andvar Exp $ */ 2 3 /* 4 * Copyright (c) 2010, Oracle America, Inc. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions are 8 * met: 9 * 10 * * Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * * Redistributions in binary form must reproduce the above 13 * copyright notice, this list of conditions and the following 14 * disclaimer in the documentation and/or other materials 15 * provided with the distribution. 16 * * Neither the name of the "Oracle America, Inc." nor the names of its 17 * contributors may be used to endorse or promote products derived 18 * from this software without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 21 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 22 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 23 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 24 * COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, 25 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE 27 * GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 28 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, 29 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING 30 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 31 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 32 */ 33 34 #include <sys/cdefs.h> 35 #if defined(LIBC_SCCS) && !defined(lint) 36 #if 0 37 static char sccsid[] = "@(#)getnetpath.c 1.11 91/12/19 SMI"; 38 #else 39 __RCSID("$NetBSD: getnetpath.c,v 1.18 2022/01/04 22:10:08 andvar Exp $"); 40 #endif 41 #endif 42 43 /* 44 * Copyright (c) 1989 by Sun Microsystems, Inc. 45 */ 46 47 #include "namespace.h" 48 #include <stdio.h> 49 #include <assert.h> 50 #include <errno.h> 51 #include <netconfig.h> 52 #include <stdlib.h> 53 #include <string.h> 54 #include <syslog.h> 55 56 #ifdef __weak_alias 57 __weak_alias(getnetpath,_getnetpath) 58 __weak_alias(setnetpath,_setnetpath) 59 __weak_alias(endnetpath,_endnetpath) 60 #endif 61 62 /* 63 * internal structure to keep track of a netpath "session" 64 */ 65 struct netpath_chain { 66 struct netconfig *ncp; /* an nconf entry */ 67 struct netpath_chain *nchain_next; /* next nconf entry allocated */ 68 }; 69 70 71 struct netpath_vars { 72 int valid; /* token that indicates a valid netpath_vars */ 73 void *nc_handlep; /* handle for current netconfig "session" */ 74 char *netpath; /* pointer to current view-point in NETPATH */ 75 char *netpath_start; /* pointer to start of our copy of NETPATH */ 76 struct netpath_chain *ncp_list; /* list of nconfs allocated this session*/ 77 }; 78 79 #define NP_VALID 0xf00d 80 #define NP_INVALID 0 81 82 char *_get_next_token(char *, int); 83 84 85 /* 86 * A call to setnetpath() establishes a NETPATH "session". setnetpath() 87 * must be called before the first call to getnetpath(). A "handle" is 88 * returned to distinguish the session; this handle should be passed 89 * subsequently to getnetpath(). (Handles are used to allow for nested calls 90 * to setnetpath()). 91 * If setnetpath() is unable to establish a session (due to lack of memory 92 * resources, or the absence of the /etc/netconfig file), a NULL pointer is 93 * returned. 94 */ 95 96 void * 97 setnetpath(void) 98 { 99 struct netpath_vars *np_sessionp; /* this session's variables */ 100 char *npp; /* NETPATH env variable */ 101 102 #ifdef MEM_CHK 103 malloc_debug(1); 104 #endif 105 106 if ((np_sessionp = malloc(sizeof(*np_sessionp))) == NULL) 107 return (NULL); 108 if ((np_sessionp->nc_handlep = setnetconfig()) == NULL) { 109 free(np_sessionp); 110 syslog (LOG_ERR, "rpc: failed to open " NETCONFIG); 111 return (NULL); 112 } 113 np_sessionp->valid = NP_VALID; 114 np_sessionp->ncp_list = NULL; 115 if ((npp = getenv(NETPATH)) == NULL) 116 np_sessionp->netpath = NULL; 117 else { 118 (void) endnetconfig(np_sessionp->nc_handlep); 119 /* won't need nc session*/ 120 np_sessionp->nc_handlep = NULL; 121 if ((np_sessionp->netpath = malloc(strlen(npp)+1)) == NULL) { 122 free(np_sessionp); 123 return (NULL); 124 } else 125 (void) strcpy(np_sessionp->netpath, npp); 126 } 127 np_sessionp->netpath_start = np_sessionp->netpath; 128 return ((void *)np_sessionp); 129 } 130 131 /* 132 * When first called, getnetpath() returns a pointer to the netconfig 133 * database entry corresponding to the first valid NETPATH component. The 134 * netconfig entry is formatted as a struct netconfig. 135 * On each subsequent call, getnetpath returns a pointer to the netconfig 136 * entry that corresponds to the next valid NETPATH component. getnetpath 137 * can thus be used to search the netconfig database for all networks 138 * included in the NETPATH variable. 139 * When NETPATH has been exhausted, getnetpath() returns NULL. It returns 140 * NULL and sets errno in case of an error (e.g., setnetpath was not called 141 * previously). 142 * getnetpath() silently ignores invalid NETPATH components. A NETPATH 143 * component is invalid if there is no corresponding entry in the netconfig 144 * database. 145 * If the NETPATH variable is unset, getnetpath() behaves as if NETPATH 146 * were set to the sequence of default or visible networks in the netconfig 147 * database, in the order in which they are listed. 148 */ 149 150 struct netconfig * 151 getnetpath(void *handlep) 152 { 153 struct netpath_vars *np_sessionp = (struct netpath_vars *)handlep; 154 struct netconfig *ncp = NULL; /* temp. holds a netconfig session */ 155 struct netpath_chain *chainp; /* holds chain of ncp's we alloc */ 156 char *npp; /* holds current NETPATH */ 157 158 if (np_sessionp == NULL || np_sessionp->valid != NP_VALID) { 159 errno = EINVAL; 160 return (NULL); 161 } 162 if (np_sessionp->netpath_start == NULL) { /* NETPATH was not set */ 163 do { /* select next visible network */ 164 if (np_sessionp->nc_handlep == NULL) { 165 np_sessionp->nc_handlep = setnetconfig(); 166 if (np_sessionp->nc_handlep == NULL) 167 syslog (LOG_ERR, 168 "rpc: failed to open " NETCONFIG); 169 } 170 if ((ncp = getnetconfig(np_sessionp->nc_handlep)) 171 == NULL) 172 return(NULL); 173 } while ((ncp->nc_flag & NC_VISIBLE) == 0); 174 return (ncp); 175 } 176 /* 177 * Find first valid network ID in netpath. 178 */ 179 while ((npp = np_sessionp->netpath) != NULL && strlen(npp) != 0) { 180 np_sessionp->netpath = _get_next_token(npp, ':'); 181 /* 182 * npp is a network identifier. 183 */ 184 if ((ncp = getnetconfigent(npp)) != NULL) { 185 /* cobble alloc chain entry */ 186 chainp = malloc(sizeof (struct netpath_chain)); 187 if (chainp == NULL) { 188 freenetconfigent(ncp); 189 return NULL; 190 } 191 chainp->ncp = ncp; 192 chainp->nchain_next = NULL; 193 if (np_sessionp->ncp_list == NULL) 194 np_sessionp->ncp_list = chainp; 195 else 196 np_sessionp->ncp_list->nchain_next = chainp; 197 return (ncp); 198 } 199 /* couldn't find this token in the database; go to next one. */ 200 } 201 return (NULL); 202 } 203 204 /* 205 * endnetpath() may be called to unbind NETPATH when processing is complete, 206 * releasing resources for reuse. It returns 0 on success and -1 on failure 207 * (e.g. if setnetpath() was not called previously. 208 */ 209 int 210 endnetpath(void *handlep) 211 { 212 struct netpath_vars *np_sessionp = (struct netpath_vars *)handlep; 213 struct netpath_chain *chainp, *lastp; 214 215 if (np_sessionp == NULL || np_sessionp->valid != NP_VALID) { 216 errno = EINVAL; 217 return (-1); 218 } 219 if (np_sessionp->nc_handlep != NULL) 220 endnetconfig(np_sessionp->nc_handlep); 221 if (np_sessionp->netpath_start != NULL) 222 free(np_sessionp->netpath_start); 223 for (chainp = np_sessionp->ncp_list; chainp != NULL; 224 lastp=chainp, chainp=chainp->nchain_next, free(lastp)) { 225 freenetconfigent(chainp->ncp); 226 } 227 free(np_sessionp); 228 #ifdef MEM_CHK 229 if (malloc_verify() == 0) { 230 fprintf(stderr, "memory heap corrupted in endnetpath\n"); 231 exit(1); 232 } 233 #endif 234 return (0); 235 } 236 237 238 /* 239 * Returns pointer to the rest-of-the-string after the current token. 240 * The token itself starts at arg, and we null terminate it. We return NULL 241 * if either the arg is empty, or if this is the last token. 242 */ 243 244 char * 245 _get_next_token( 246 char *npp, /* string */ 247 int token /* char to parse string for */ 248 ) 249 { 250 char *cp; /* char pointer */ 251 char *np; /* netpath pointer */ 252 char *ep; /* escape pointer */ 253 254 _DIAGASSERT(npp != NULL); 255 256 if ((cp = strchr(npp, token)) == NULL) 257 return (NULL); 258 /* 259 * did find a token, but it might be escaped. 260 */ 261 if ((cp > npp) && (cp[-1] == '\\')) { 262 /* 263 * if slash was also escaped, carry on, otherwise find 264 * next token 265 */ 266 if ((cp > npp + 1) && (cp[-2] != '\\')) { 267 /* shift r-o-s onto the escaped token */ 268 strcpy(&cp[-1], cp); /* XXX: overlapping string copy */ 269 /* 270 * Do a recursive call. 271 * We don't know how many escaped tokens there might be. 272 */ 273 return (_get_next_token(cp, token)); 274 } 275 } 276 277 *cp++ = '\0'; /* null-terminate token */ 278 /* get rid of any backslash escapes */ 279 ep = npp; 280 while ((np = strchr(ep, '\\')) != 0) { 281 if (np[1] == '\\') 282 np++; 283 strcpy(np, (ep = &np[1])); /* XXX: overlapping string copy */ 284 } 285 return (cp); /* return ptr to r-o-s */ 286 } 287
Indexes created Tue Sep 23 14:10:03 GMT 2025