usr/src/lib/nsswitch/files/common/bootparams_getbyname.c

   1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License (the "License").
   6  * You may not use this file except in compliance with the License.
   7  *
   8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
   9  * or http://www.opensolaris.org/os/licensing.
  10  * See the License for the specific language governing permissions
  11  * and limitations under the License.
  12  *
  13  * When distributing Covered Code, include this CDDL HEADER in each
  14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  15  * If applicable, add the following below this CDDL HEADER, with the
  16  * fields enclosed by brackets "[]" replaced with your own identifying
  17  * information: Portions Copyright [yyyy] [name of copyright owner]
  18  *
  19  * CDDL HEADER END
  20  */
  21 /*
  22  * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
  23  * Use is subject to license terms.
  24  *
  25  *      files/bootparams_getbyname.c -- "files" backend for
  26  *      nsswitch "bootparams" database.
  27  */
  28
  29 #pragma ident   "%Z%%M% %I%     %E% SMI"
  30
  31 static const char *bootparams = "/etc/bootparams";
  32
  33 #include "files_common.h"
  34 #include <stdlib.h>
  35 #include <ctype.h>
  36 #include <strings.h>
  37
  38 static nss_status_t _nss_files_XY_bootparams(files_backend_ptr_t,
  39         nss_XbyY_args_t *, const char *);
  40
  41 static nss_status_t
  42 getbyname(be, a)
  43         files_backend_ptr_t     be;
  44         void                    *a;
  45 {
  46         nss_XbyY_args_t         *argp = (nss_XbyY_args_t *)a;
  47         nss_status_t            res;
  48
  49         /* bootparams_getbyname() has not set/endent; rewind on each call */
  50         if ((res = _nss_files_setent(be, 0)) != NSS_SUCCESS) {
  51                 return (res);
  52         }
  53         return (_nss_files_XY_bootparams(be, argp, argp->key.name));
  54 }
  55
  56 static files_backend_op_t bootparams_ops[] = {
  57         _nss_files_destr,
  58         getbyname
  59 };
  60
  61 /*ARGSUSED*/
  62 nss_backend_t *
  63 _nss_files_bootparams_constr(dummy1, dummy2, dummy3)
  64         const char      *dummy1, *dummy2, *dummy3;
  65 {
  66         return (_nss_files_constr(bootparams_ops,
  67                 sizeof (bootparams_ops) / sizeof (bootparams_ops[0]),
  68                 bootparams,
  69                 NSS_LINELEN_BOOTPARAMS,
  70                 NULL));
  71 }
  72
  73 /*
  74  * bootparams has the hostname as part of the data in the file, but the other
  75  * backends don't include it in the data passed to the backend.  For this
  76  * reason, we process everything here and don't bother calling the backend.
  77  */
  78 /*ARGSUSED*/
  79 static nss_status_t
  80 _nss_files_XY_bootparams(be, args, filter)
  81         files_backend_ptr_t     be;
  82         nss_XbyY_args_t         *args;
  83         const char              *filter;
  84                         /*
  85                          * filter not useful here since the key
  86                          * we are looking for is the first "word"
  87                          * on the line and we can be fast enough.
  88                          */
  89 {
  90         nss_status_t            res;
  91
  92         if (be->buf == 0 &&
  93                 (be->buf = (char *)malloc(be->minbuf)) == 0) {
  94                 (void) _nss_files_endent(be, 0);
  95                 return (NSS_UNAVAIL); /* really panic, malloc failed */
  96         }
  97
  98         res = NSS_NOTFOUND;
  99
 100         /*CONSTCOND*/
 101         while (1) {
 102                 char            *instr  = be->buf;
 103                 char            *p, *host, *limit;
 104                 int             linelen;
 105
 106                 /*
 107                  * _nss_files_read_line does process the '\' that are used
 108                  * in /etc/bootparams for continuation and gives one long
 109                  * buffer.
 110                  *
 111                  * linelen counts the characters up to but excluding the '\n'
 112                  */
 113                 if ((linelen = _nss_files_read_line(be->f, instr,
 114                     be->minbuf)) < 0) {
 115                         /* End of file */
 116                         args->returnval = 0;
 117                         args->returnlen = 0;
 118                         break;
 119                 }
 120
 121                 /*
 122                  * we need to strip off the host name before returning it.
 123                  */
 124                 p = instr;
 125                 limit = p + linelen;
 126
 127                 /* Skip over leading whitespace */
 128                 while (p < limit && isspace(*p)) {
 129                         p++;
 130                 }
 131                 host = p;
 132
 133                 /* Skip over the hostname */
 134                 while (p < limit && !isspace(*p)) {
 135                         p++;
 136                 }
 137                 *p++ = '\0';
 138
 139                 if (strcasecmp(args->key.name, host) != 0) {
 140                         continue;
 141                 }
 142
 143                 /* Skip over whitespace between name and first datum */
 144                 while (p < limit && isspace(*p)) {
 145                         p++;
 146                 }
 147                 if (p >= limit) {
 148                         /* Syntax error -- no data! Just skip it. */
 149                         continue;
 150                 }
 151
 152                 linelen -= (p - instr);
 153                 if (args->buf.buflen <= linelen) {      /* not enough buffer */
 154                         args->erange = 1;
 155                         break;
 156                 }
 157                 (void) memcpy(args->buf.buffer, p, linelen);
 158                 args->buf.buffer[linelen] = '\0';
 159                 args->returnval = args->buf.result;
 160                 args->returnlen = linelen;
 161                 res = NSS_SUCCESS;
 162                 break;
 163         }
 164         (void) _nss_files_endent(be, 0);
 165         return (res);
 166 }