1 /*- 2 * Copyright (c) 2009, Sun Microsystems, Inc. 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions are met: 7 * - Redistributions of source code must retain the above copyright notice, 8 * this list of conditions and the following disclaimer. 9 * - Redistributions in binary form must reproduce the above copyright notice, 10 * this list of conditions and the following disclaimer in the documentation 11 * and/or other materials provided with the distribution. 12 * - Neither the name of Sun Microsystems, Inc. nor the names of its 13 * contributors may be used to endorse or promote products derived 14 * from this software without specific prior written permission. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 17 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE 20 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 21 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 22 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 23 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 24 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 25 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 26 * POSSIBILITY OF SUCH DAMAGE. 27 * 28 * @(#)getnetpath.c 1.11 91/12/19 SMI 29 * $NetBSD: getnetpath.c,v 1.3 2000/07/06 03:10:34 christos Exp $ 30 * $FreeBSD: src/lib/libc/rpc/getnetpath.c,v 1.8 2007/09/20 22:35:24 matteo Exp $ 31 */ 32 33 /* 34 * Copyright (c) 1989 by Sun Microsystems, Inc. 35 */ 36 37 #include "namespace.h" 38 #include <stdio.h> 39 #include <errno.h> 40 #include <netconfig.h> 41 #include <stdlib.h> 42 #include <string.h> 43 #include <syslog.h> 44 #include "un-namespace.h" 45 46 /* 47 * internal structure to keep track of a netpath "session" 48 */ 49 struct netpath_chain { 50 struct netconfig *ncp; /* an nconf entry */ 51 struct netpath_chain *nchain_next; /* next nconf entry allocated */ 52 }; 53 54 55 struct netpath_vars { 56 int valid; /* token that indicates a valid netpath_vars */ 57 void *nc_handlep; /* handle for current netconfig "session" */ 58 char *netpath; /* pointer to current view-point in NETPATH */ 59 char *netpath_start; /* pointer to start of our copy of NETPATH */ 60 struct netpath_chain *ncp_list; /* list of nconfs allocated this session*/ 61 }; 62 63 #define NP_VALID 0xf00d 64 #define NP_INVALID 0 65 66 char *_get_next_token(char *, int); 67 68 69 /* 70 * A call to setnetpath() establishes a NETPATH "session". setnetpath() 71 * must be called before the first call to getnetpath(). A "handle" is 72 * returned to distinguish the session; this handle should be passed 73 * subsequently to getnetpath(). (Handles are used to allow for nested calls 74 * to setnetpath()). 75 * If setnetpath() is unable to establish a session (due to lack of memory 76 * resources, or the absence of the /etc/netconfig file), a NULL pointer is 77 * returned. 78 */ 79 80 void * 81 setnetpath(void) 82 { 83 84 struct netpath_vars *np_sessionp; /* this session's variables */ 85 char *npp; /* NETPATH env variable */ 86 87 #ifdef MEM_CHK 88 malloc_debug(1); 89 #endif 90 91 if ((np_sessionp = 92 (struct netpath_vars *)malloc(sizeof (struct netpath_vars))) == NULL) { 93 return (NULL); 94 } 95 if ((np_sessionp->nc_handlep = setnetconfig()) == NULL) { 96 syslog (LOG_ERR, "rpc: failed to open " NETCONFIG); 97 goto failed; 98 } 99 np_sessionp->valid = NP_VALID; 100 np_sessionp->ncp_list = NULL; 101 if ((npp = getenv(NETPATH)) == NULL) { 102 np_sessionp->netpath = NULL; 103 } else { 104 endnetconfig(np_sessionp->nc_handlep);/* won't need nc session*/ 105 np_sessionp->nc_handlep = NULL; 106 if ((np_sessionp->netpath = malloc(strlen(npp)+1)) == NULL) 107 goto failed; 108 else { 109 strcpy(np_sessionp->netpath, npp); 110 } 111 } 112 np_sessionp->netpath_start = np_sessionp->netpath; 113 return ((void *)np_sessionp); 114 115 failed: 116 free(np_sessionp); 117 return (NULL); 118 } 119 120 /* 121 * When first called, getnetpath() returns a pointer to the netconfig 122 * database entry corresponding to the first valid NETPATH component. The 123 * netconfig entry is formatted as a struct netconfig. 124 * On each subsequent call, getnetpath returns a pointer to the netconfig 125 * entry that corresponds to the next valid NETPATH component. getnetpath 126 * can thus be used to search the netconfig database for all networks 127 * included in the NETPATH variable. 128 * When NETPATH has been exhausted, getnetpath() returns NULL. It returns 129 * NULL and sets errno in case of an error (e.g., setnetpath was not called 130 * previously). 131 * getnetpath() silently ignores invalid NETPATH components. A NETPATH 132 * compnent is invalid if there is no corresponding entry in the netconfig 133 * database. 134 * If the NETPATH variable is unset, getnetpath() behaves as if NETPATH 135 * were set to the sequence of default or visible networks in the netconfig 136 * database, in the order in which they are listed. 137 */ 138 139 struct netconfig * 140 getnetpath(void *handlep) 141 { 142 struct netpath_vars *np_sessionp = (struct netpath_vars *)handlep; 143 struct netconfig *ncp = NULL; /* temp. holds a netconfig session */ 144 struct netpath_chain *chainp; /* holds chain of ncp's we alloc */ 145 char *npp; /* holds current NETPATH */ 146 147 if (np_sessionp == NULL || np_sessionp->valid != NP_VALID) { 148 errno = EINVAL; 149 return (NULL); 150 } 151 if (np_sessionp->netpath_start == NULL) { /* NETPATH was not set */ 152 do { /* select next visible network */ 153 if (np_sessionp->nc_handlep == NULL) { 154 np_sessionp->nc_handlep = setnetconfig(); 155 if (np_sessionp->nc_handlep == NULL) 156 syslog (LOG_ERR, "rpc: failed to open " NETCONFIG); 157 } 158 if ((ncp = getnetconfig(np_sessionp->nc_handlep)) == NULL) { 159 return(NULL); 160 } 161 } while ((ncp->nc_flag & NC_VISIBLE) == 0); 162 return (ncp); 163 } 164 /* 165 * Find first valid network ID in netpath. 166 */ 167 while ((npp = np_sessionp->netpath) != NULL && strlen(npp) != 0) { 168 np_sessionp->netpath = _get_next_token(npp, ':'); 169 /* 170 * npp is a network identifier. 171 */ 172 if ((ncp = getnetconfigent(npp)) != NULL) { 173 chainp = (struct netpath_chain *) /* cobble alloc chain entry */ 174 malloc(sizeof (struct netpath_chain)); 175 chainp->ncp = ncp; 176 chainp->nchain_next = NULL; 177 if (np_sessionp->ncp_list == NULL) { 178 np_sessionp->ncp_list = chainp; 179 } else { 180 np_sessionp->ncp_list->nchain_next = chainp; 181 } 182 return (ncp); 183 } 184 /* couldn't find this token in the database; go to next one. */ 185 } 186 return (NULL); 187 } 188 189 /* 190 * endnetpath() may be called to unbind NETPATH when processing is complete, 191 * releasing resources for reuse. It returns 0 on success and -1 on failure 192 * (e.g. if setnetpath() was not called previously. 193 */ 194 int 195 endnetpath(void *handlep) 196 { 197 struct netpath_vars *np_sessionp = (struct netpath_vars *)handlep; 198 struct netpath_chain *chainp, *lastp; 199 200 if (np_sessionp == NULL || np_sessionp->valid != NP_VALID) { 201 errno = EINVAL; 202 return (-1); 203 } 204 if (np_sessionp->nc_handlep != NULL) 205 endnetconfig(np_sessionp->nc_handlep); 206 if (np_sessionp->netpath_start != NULL) 207 free(np_sessionp->netpath_start); 208 for (chainp = np_sessionp->ncp_list; chainp != NULL; 209 lastp=chainp, chainp=chainp->nchain_next, free(lastp)) { 210 freenetconfigent(chainp->ncp); 211 } 212 free(np_sessionp); 213 #ifdef MEM_CHK 214 if (malloc_verify() == 0) { 215 fprintf(stderr, "memory heap corrupted in endnetpath\n"); 216 exit(1); 217 } 218 #endif 219 return (0); 220 } 221 222 223 224 /* 225 * Returns pointer to the rest-of-the-string after the current token. 226 * The token itself starts at arg, and we null terminate it. We return NULL 227 * if either the arg is empty, or if this is the last token. 228 */ 229 230 char * 231 _get_next_token(char *npp, /* string */ 232 int token) /* char to parse string for */ 233 { 234 char *cp; /* char pointer */ 235 char *np; /* netpath pointer */ 236 char *ep; /* escape pointer */ 237 238 if ((cp = strchr(npp, token)) == NULL) { 239 return (NULL); 240 } 241 /* 242 * did find a token, but it might be escaped. 243 */ 244 if ((cp > npp) && (cp[-1] == '\\')) { 245 /* if slash was also escaped, carry on, otherwise find next token */ 246 if ((cp > npp + 1) && (cp[-2] != '\\')) { 247 /* shift r-o-s onto the escaped token */ 248 strcpy(&cp[-1], cp); /* XXX: overlapping string copy */ 249 /* 250 * Do a recursive call. 251 * We don't know how many escaped tokens there might be. 252 */ 253 return (_get_next_token(cp, token)); 254 } 255 } 256 257 *cp++ = '\0'; /* null-terminate token */ 258 /* get rid of any backslash escapes */ 259 ep = npp; 260 while ((np = strchr(ep, '\\')) != NULL) { 261 if (np[1] == '\\') 262 np++; 263 strcpy(np, (ep = &np[1])); /* XXX: overlapping string copy */ 264 } 265 return (cp); /* return ptr to r-o-s */ 266 } 267