1 /* 2 * Sun RPC is a product of Sun Microsystems, Inc. and is provided for 3 * unrestricted use provided that this legend is included on all tape 4 * media and as a part of the software program in whole or part. Users 5 * may copy or modify Sun RPC without charge, but are not authorized 6 * to license or distribute it to anyone else except as part of a product or 7 * program developed by the user or with the express written consent of 8 * Sun Microsystems, Inc. 9 * 10 * SUN RPC IS PROVIDED AS IS WITH NO WARRANTIES OF ANY KIND INCLUDING THE 11 * WARRANTIES OF DESIGN, MERCHANTIBILITY AND FITNESS FOR A PARTICULAR 12 * PURPOSE, OR ARISING FROM A COURSE OF DEALING, USAGE OR TRADE PRACTICE. 13 * 14 * Sun RPC is provided with no support and without any obligation on the 15 * part of Sun Microsystems, Inc. to assist in its use, correction, 16 * modification or enhancement. 17 * 18 * SUN MICROSYSTEMS, INC. SHALL HAVE NO LIABILITY WITH RESPECT TO THE 19 * INFRINGEMENT OF COPYRIGHTS, TRADE SECRETS OR ANY PATENTS BY SUN RPC 20 * OR ANY PART THEREOF. 21 * 22 * In no event will Sun Microsystems, Inc. be liable for any lost revenue 23 * or profits or other special, indirect and consequential damages, even if 24 * Sun has been advised of the possibility of such damages. 25 * 26 * Sun Microsystems, Inc. 27 * 2550 Garcia Avenue 28 * Mountain View, California 94043 29 * 30 * @(#)getnetpath.c 1.11 91/12/19 SMI 31 * $NetBSD: getnetpath.c,v 1.3 2000/07/06 03:10:34 christos Exp $ 32 * $FreeBSD: src/lib/libc/rpc/getnetpath.c,v 1.8 2007/09/20 22:35:24 matteo Exp $ 33 * $DragonFly$ 34 */ 35 36 /* 37 * Copyright (c) 1989 by Sun Microsystems, Inc. 38 */ 39 40 #include "namespace.h" 41 #include <stdio.h> 42 #include <errno.h> 43 #include <netconfig.h> 44 #include <stdlib.h> 45 #include <string.h> 46 #include <syslog.h> 47 #include "un-namespace.h" 48 49 /* 50 * internal structure to keep track of a netpath "session" 51 */ 52 struct netpath_chain { 53 struct netconfig *ncp; /* an nconf entry */ 54 struct netpath_chain *nchain_next; /* next nconf entry allocated */ 55 }; 56 57 58 struct netpath_vars { 59 int valid; /* token that indicates a valid netpath_vars */ 60 void *nc_handlep; /* handle for current netconfig "session" */ 61 char *netpath; /* pointer to current view-point in NETPATH */ 62 char *netpath_start; /* pointer to start of our copy of NETPATH */ 63 struct netpath_chain *ncp_list; /* list of nconfs allocated this session*/ 64 }; 65 66 #define NP_VALID 0xf00d 67 #define NP_INVALID 0 68 69 char *_get_next_token(char *, int); 70 71 72 /* 73 * A call to setnetpath() establishes a NETPATH "session". setnetpath() 74 * must be called before the first call to getnetpath(). A "handle" is 75 * returned to distinguish the session; this handle should be passed 76 * subsequently to getnetpath(). (Handles are used to allow for nested calls 77 * to setnetpath()). 78 * If setnetpath() is unable to establish a session (due to lack of memory 79 * resources, or the absence of the /etc/netconfig file), a NULL pointer is 80 * returned. 81 */ 82 83 void * 84 setnetpath(void) 85 { 86 87 struct netpath_vars *np_sessionp; /* this session's variables */ 88 char *npp; /* NETPATH env variable */ 89 90 #ifdef MEM_CHK 91 malloc_debug(1); 92 #endif 93 94 if ((np_sessionp = 95 (struct netpath_vars *)malloc(sizeof (struct netpath_vars))) == NULL) { 96 return (NULL); 97 } 98 if ((np_sessionp->nc_handlep = setnetconfig()) == NULL) { 99 free(np_sessionp); 100 syslog (LOG_ERR, "rpc: failed to open " NETCONFIG); 101 goto failed; 102 } 103 np_sessionp->valid = NP_VALID; 104 np_sessionp->ncp_list = NULL; 105 if ((npp = getenv(NETPATH)) == NULL) { 106 np_sessionp->netpath = NULL; 107 } else { 108 endnetconfig(np_sessionp->nc_handlep);/* won't need nc session*/ 109 np_sessionp->nc_handlep = NULL; 110 if ((np_sessionp->netpath = malloc(strlen(npp)+1)) == NULL) 111 goto failed; 112 else { 113 strcpy(np_sessionp->netpath, npp); 114 } 115 } 116 np_sessionp->netpath_start = np_sessionp->netpath; 117 return ((void *)np_sessionp); 118 119 failed: 120 free(np_sessionp); 121 return (NULL); 122 } 123 124 /* 125 * When first called, getnetpath() returns a pointer to the netconfig 126 * database entry corresponding to the first valid NETPATH component. The 127 * netconfig entry is formatted as a struct netconfig. 128 * On each subsequent call, getnetpath returns a pointer to the netconfig 129 * entry that corresponds to the next valid NETPATH component. getnetpath 130 * can thus be used to search the netconfig database for all networks 131 * included in the NETPATH variable. 132 * When NETPATH has been exhausted, getnetpath() returns NULL. It returns 133 * NULL and sets errno in case of an error (e.g., setnetpath was not called 134 * previously). 135 * getnetpath() silently ignores invalid NETPATH components. A NETPATH 136 * compnent is invalid if there is no corresponding entry in the netconfig 137 * database. 138 * If the NETPATH variable is unset, getnetpath() behaves as if NETPATH 139 * were set to the sequence of default or visible networks in the netconfig 140 * database, in the order in which they are listed. 141 */ 142 143 struct netconfig * 144 getnetpath(void *handlep) 145 { 146 struct netpath_vars *np_sessionp = (struct netpath_vars *)handlep; 147 struct netconfig *ncp = NULL; /* temp. holds a netconfig session */ 148 struct netpath_chain *chainp; /* holds chain of ncp's we alloc */ 149 char *npp; /* holds current NETPATH */ 150 151 if (np_sessionp == NULL || np_sessionp->valid != NP_VALID) { 152 errno = EINVAL; 153 return (NULL); 154 } 155 if (np_sessionp->netpath_start == NULL) { /* NETPATH was not set */ 156 do { /* select next visible network */ 157 if (np_sessionp->nc_handlep == NULL) { 158 np_sessionp->nc_handlep = setnetconfig(); 159 if (np_sessionp->nc_handlep == NULL) 160 syslog (LOG_ERR, "rpc: failed to open " NETCONFIG); 161 } 162 if ((ncp = getnetconfig(np_sessionp->nc_handlep)) == NULL) { 163 return(NULL); 164 } 165 } while ((ncp->nc_flag & NC_VISIBLE) == 0); 166 return (ncp); 167 } 168 /* 169 * Find first valid network ID in netpath. 170 */ 171 while ((npp = np_sessionp->netpath) != NULL && strlen(npp) != 0) { 172 np_sessionp->netpath = _get_next_token(npp, ':'); 173 /* 174 * npp is a network identifier. 175 */ 176 if ((ncp = getnetconfigent(npp)) != NULL) { 177 chainp = (struct netpath_chain *) /* cobble alloc chain entry */ 178 malloc(sizeof (struct netpath_chain)); 179 chainp->ncp = ncp; 180 chainp->nchain_next = NULL; 181 if (np_sessionp->ncp_list == NULL) { 182 np_sessionp->ncp_list = chainp; 183 } else { 184 np_sessionp->ncp_list->nchain_next = chainp; 185 } 186 return (ncp); 187 } 188 /* couldn't find this token in the database; go to next one. */ 189 } 190 return (NULL); 191 } 192 193 /* 194 * endnetpath() may be called to unbind NETPATH when processing is complete, 195 * releasing resources for reuse. It returns 0 on success and -1 on failure 196 * (e.g. if setnetpath() was not called previously. 197 */ 198 int 199 endnetpath(void *handlep) 200 { 201 struct netpath_vars *np_sessionp = (struct netpath_vars *)handlep; 202 struct netpath_chain *chainp, *lastp; 203 204 if (np_sessionp == NULL || np_sessionp->valid != NP_VALID) { 205 errno = EINVAL; 206 return (-1); 207 } 208 if (np_sessionp->nc_handlep != NULL) 209 endnetconfig(np_sessionp->nc_handlep); 210 if (np_sessionp->netpath_start != NULL) 211 free(np_sessionp->netpath_start); 212 for (chainp = np_sessionp->ncp_list; chainp != NULL; 213 lastp=chainp, chainp=chainp->nchain_next, free(lastp)) { 214 freenetconfigent(chainp->ncp); 215 } 216 free(np_sessionp); 217 #ifdef MEM_CHK 218 if (malloc_verify() == 0) { 219 fprintf(stderr, "memory heap corrupted in endnetpath\n"); 220 exit(1); 221 } 222 #endif 223 return (0); 224 } 225 226 227 228 /* 229 * Returns pointer to the rest-of-the-string after the current token. 230 * The token itself starts at arg, and we null terminate it. We return NULL 231 * if either the arg is empty, or if this is the last token. 232 */ 233 234 char * 235 _get_next_token(char *npp, /* string */ 236 int token) /* char to parse string for */ 237 { 238 char *cp; /* char pointer */ 239 char *np; /* netpath pointer */ 240 char *ep; /* escape pointer */ 241 242 if ((cp = strchr(npp, token)) == NULL) { 243 return (NULL); 244 } 245 /* 246 * did find a token, but it might be escaped. 247 */ 248 if ((cp > npp) && (cp[-1] == '\\')) { 249 /* if slash was also escaped, carry on, otherwise find next token */ 250 if ((cp > npp + 1) && (cp[-2] != '\\')) { 251 /* shift r-o-s onto the escaped token */ 252 strcpy(&cp[-1], cp); /* XXX: overlapping string copy */ 253 /* 254 * Do a recursive call. 255 * We don't know how many escaped tokens there might be. 256 */ 257 return (_get_next_token(cp, token)); 258 } 259 } 260 261 *cp++ = '\0'; /* null-terminate token */ 262 /* get rid of any backslash escapes */ 263 ep = npp; 264 while ((np = strchr(ep, '\\')) != 0) { 265 if (np[1] == '\\') 266 np++; 267 strcpy(np, (ep = &np[1])); /* XXX: overlapping string copy */ 268 } 269 return (cp); /* return ptr to r-o-s */ 270 } 271