lib/libc/gen/pw_scan.c

   1 /*-
   2  * Copyright (c) 1990, 1993, 1994
   3  *      The Regents of the University of California.  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
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 4. Neither the name of the University nor the names of its contributors
  14  *    may be used to endorse or promote products derived from this software
  15  *    without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27  * SUCH DAMAGE.
  28  *
  29  * @(#)pw_scan.c        8.3 (Berkeley) 4/2/94
  30  * $FreeBSD: src/lib/libc/gen/pw_scan.c,v 1.26 2007/01/09 00:27:55 imp Exp $
  31  * $DragonFly: src/usr.sbin/pwd_mkdb/pw_scan.c,v 1.3 2005/12/05 02:40:27 swildner Exp $
  32  */
  33
  34 /*
  35  * This module is used to "verify" password entries by chpass(1) and
  36  * pwd_mkdb(8).
  37  */
  38
  39 #include <sys/param.h>
  40
  41 #include <err.h>
  42 #include <errno.h>
  43 #include <fcntl.h>
  44 #include <pwd.h>
  45 #include <stdio.h>
  46 #include <string.h>
  47 #include <stdlib.h>
  48 #include <unistd.h>
  49
  50 #include "pw_scan.h"
  51
  52 /*
  53  * Some software assumes that IDs are short.  We should emit warnings
  54  * for id's which cannot be stored in a short, but we are more liberal
  55  * by default, warning for IDs greater than USHRT_MAX.
  56  *
  57  * If pw_big_ids_warning is -1 on entry to pw_scan(), it will be set based
  58  * on the existence of PW_SCAN_BIG_IDS in the environment.
  59  */
  60 static int      pw_big_ids_warning = -1;
  61
  62 int
  63 __pw_scan(char *bp, struct passwd *pw, int flags)
  64 {
  65         uid_t id;
  66         int root;
  67         char *ep, *p, *sh;
  68
  69         if (pw_big_ids_warning == -1)
  70                 pw_big_ids_warning = getenv("PW_SCAN_BIG_IDS") == NULL ? 1 : 0;
  71
  72         pw->pw_fields = 0;
  73         if (!(pw->pw_name = strsep(&bp, ":")))          /* login */
  74                 goto fmt;
  75         root = !strcmp(pw->pw_name, "root");
  76         if (pw->pw_name[0] && (pw->pw_name[0] != '+' || pw->pw_name[1] == '\0'))
  77                 pw->pw_fields |= _PWF_NAME;
  78
  79         if (!(pw->pw_passwd = strsep(&bp, ":")))        /* passwd */
  80                 goto fmt;
  81         if (pw->pw_passwd[0])
  82                 pw->pw_fields |= _PWF_PASSWD;
  83
  84         if (!(p = strsep(&bp, ":")))                    /* uid */
  85                 goto fmt;
  86         if (p[0])
  87                 pw->pw_fields |= _PWF_UID;
  88         else {
  89                 if (pw->pw_name[0] != '+' && pw->pw_name[0] != '-') {
  90                         if (flags & _PWSCAN_WARN)
  91                                 warnx("no uid for user %s", pw->pw_name);
  92                         return (0);
  93                 }
  94         }
  95         id = strtoul(p, &ep, 10);
  96         if (errno == ERANGE) {
  97                 if (flags & _PWSCAN_WARN)
  98                         warnx("%s > max uid value (%lu)", p, ULONG_MAX);
  99                 return (0);
 100         }
 101         if (*ep != '\0') {
 102                 if (flags & _PWSCAN_WARN)
 103                         warnx("%s uid is incorrect", p);
 104                 return (0);
 105         }
 106         if (root && id) {
 107                 if (flags & _PWSCAN_WARN)
 108                         warnx("root uid should be 0");
 109                 return (0);
 110         }
 111         if (flags & _PWSCAN_WARN && pw_big_ids_warning && id > USHRT_MAX) {
 112                 warnx("%s > recommended max uid value (%u)", p, USHRT_MAX);
 113                 /*return (0);*/ /* THIS SHOULD NOT BE FATAL! */
 114         }
 115         pw->pw_uid = id;
 116
 117         if (!(p = strsep(&bp, ":")))                    /* gid */
 118                 goto fmt;
 119         if (p[0])
 120                 pw->pw_fields |= _PWF_GID;
 121         else {
 122                 if (pw->pw_name[0] != '+' && pw->pw_name[0] != '-') {
 123                         if (flags & _PWSCAN_WARN)
 124                                 warnx("no gid for user %s", pw->pw_name);
 125                         return (0);
 126                 }
 127         }
 128         id = strtoul(p, &ep, 10);
 129         if (errno == ERANGE) {
 130                 if (flags & _PWSCAN_WARN)
 131                         warnx("%s > max gid value (%lu)", p, ULONG_MAX);
 132                 return (0);
 133         }
 134         if (*ep != '\0') {
 135                 if (flags & _PWSCAN_WARN)
 136                         warnx("%s gid is incorrect", p);
 137                 return (0);
 138         }
 139         if (flags & _PWSCAN_WARN && pw_big_ids_warning && id > USHRT_MAX) {
 140                 warnx("%s > recommended max gid value (%u)", p, USHRT_MAX);
 141                 /* return (0); This should not be fatal! */
 142         }
 143         pw->pw_gid = id;
 144
 145         if (flags & _PWSCAN_MASTER ) {
 146                 if (!(pw->pw_class = strsep(&bp, ":"))) /* class */
 147                         goto fmt;
 148                 if (pw->pw_class[0])
 149                         pw->pw_fields |= _PWF_CLASS;
 150
 151                 if (!(p = strsep(&bp, ":")))            /* change */
 152                         goto fmt;
 153                 if (p[0])
 154                         pw->pw_fields |= _PWF_CHANGE;
 155                 pw->pw_change = atol(p);
 156
 157                 if (!(p = strsep(&bp, ":")))            /* expire */
 158                         goto fmt;
 159                 if (p[0])
 160                         pw->pw_fields |= _PWF_EXPIRE;
 161                 pw->pw_expire = atol(p);
 162         }
 163         if (!(pw->pw_gecos = strsep(&bp, ":")))         /* gecos */
 164                 goto fmt;
 165         if (pw->pw_gecos[0])
 166                 pw->pw_fields |= _PWF_GECOS;
 167
 168         if (!(pw->pw_dir = strsep(&bp, ":")))           /* directory */
 169                 goto fmt;
 170         if (pw->pw_dir[0])
 171                 pw->pw_fields |= _PWF_DIR;
 172
 173         if (!(pw->pw_shell = strsep(&bp, ":")))         /* shell */
 174                 goto fmt;
 175
 176         p = pw->pw_shell;
 177         if (root && *p) {                               /* empty == /bin/sh */
 178                 for (setusershell();;) {
 179                         if (!(sh = getusershell())) {
 180                                 if (flags & _PWSCAN_WARN)
 181                                         warnx("warning, unknown root shell");
 182                                 break;
 183                         }
 184                         if (!strcmp(p, sh))
 185                                 break;
 186                 }
 187                 endusershell();
 188         }
 189         if (p[0])
 190                 pw->pw_fields |= _PWF_SHELL;
 191
 192         if ((p = strsep(&bp, ":"))) {                   /* too many */
 193 fmt:
 194                 if (flags & _PWSCAN_WARN)
 195                         warnx("corrupted entry");
 196                 return (0);
 197         }
 198         return (1);
 199 }