lib/libutil/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  * 3. All advertising materials mentioning features or use of this software
  14  *    must display the following acknowledgement:
  15  *      This product includes software developed by the University of
  16  *      California, Berkeley and its contributors.
  17  * 4. Neither the name of the University nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  *
  33  * $FreeBSD: src/lib/libc/gen/pw_scan.c,v 1.25 2004/01/18 21:33:25 charnier Exp $
  34  * $DragonFly: src/lib/libutil/pw_scan.c,v 1.2 2005/08/01 22:59:46 joerg Exp $
  35  */
  36
  37 /*
  38  * This module is used to "verify" password entries by chpass(1) and
  39  * pwd_mkdb(8).
  40  */
  41
  42 #include <sys/param.h>
  43
  44 #include <err.h>
  45 #include <errno.h>
  46 #include <fcntl.h>
  47 #include <pwd.h>
  48 #include <stdio.h>
  49 #include <string.h>
  50 #include <stdlib.h>
  51 #include <unistd.h>
  52
  53 #include <libutil.h>
  54
  55 /*
  56  * Some software assumes that IDs are short.  We should emit warnings
  57  * for id's which cannot be stored in a short, but we are more liberal
  58  * by default, warning for IDs greater than USHRT_MAX.
  59  *
  60  * If pw_big_ids_warning is -1 on entry to pw_scan(), it will be set based
  61  * on the existence of PW_SCAN_BIG_IDS in the environment.
  62  */
  63 static int      pw_big_ids_warning = -1;
  64
  65 int
  66 __pw_scan(char *bp, struct passwd *pw, int flags)
  67 {
  68         uid_t id;
  69         int root;
  70         char *ep, *p, *sh;
  71
  72         if (pw_big_ids_warning == -1)
  73                 pw_big_ids_warning = getenv("PW_SCAN_BIG_IDS") == NULL ? 1 : 0;
  74
  75         pw->pw_fields = 0;
  76         if (!(pw->pw_name = strsep(&bp, ":")))          /* login */
  77                 goto fmt;
  78         root = !strcmp(pw->pw_name, "root");
  79         if (pw->pw_name[0] && (pw->pw_name[0] != '+' || pw->pw_name[1] == '\0'))
  80                 pw->pw_fields |= _PWF_NAME;
  81
  82         if (!(pw->pw_passwd = strsep(&bp, ":")))        /* passwd */
  83                 goto fmt;
  84         if (pw->pw_passwd[0])
  85                 pw->pw_fields |= _PWF_PASSWD;
  86
  87         if (!(p = strsep(&bp, ":")))                    /* uid */
  88                 goto fmt;
  89         if (p[0])
  90                 pw->pw_fields |= _PWF_UID;
  91         else {
  92                 if (pw->pw_name[0] != '+' && pw->pw_name[0] != '-') {
  93                         if (flags & _PWSCAN_WARN)
  94                                 warnx("no uid for user %s", pw->pw_name);
  95                         return (0);
  96                 }
  97         }
  98         id = strtoul(p, &ep, 10);
  99         if (errno == ERANGE) {
 100                 if (flags & _PWSCAN_WARN)
 101                         warnx("%s > max uid value (%lu)", p, ULONG_MAX);
 102                 return (0);
 103         }
 104         if (*ep != '\0') {
 105                 if (flags & _PWSCAN_WARN)
 106                         warnx("%s uid is incorrect", p);
 107                 return (0);
 108         }
 109         if (root && id) {
 110                 if (flags & _PWSCAN_WARN)
 111                         warnx("root uid should be 0");
 112                 return (0);
 113         }
 114         if (flags & _PWSCAN_WARN && pw_big_ids_warning && id > USHRT_MAX) {
 115                 warnx("%s > recommended max uid value (%u)", p, USHRT_MAX);
 116                 /*return (0);*/ /* THIS SHOULD NOT BE FATAL! */
 117         }
 118         pw->pw_uid = id;
 119
 120         if (!(p = strsep(&bp, ":")))                    /* gid */
 121                 goto fmt;
 122         if (p[0])
 123                 pw->pw_fields |= _PWF_GID;
 124         else {
 125                 if (pw->pw_name[0] != '+' && pw->pw_name[0] != '-') {
 126                         if (flags & _PWSCAN_WARN)
 127                                 warnx("no gid for user %s", pw->pw_name);
 128                         return (0);
 129                 }
 130         }
 131         id = strtoul(p, &ep, 10);
 132         if (errno == ERANGE) {
 133                 if (flags & _PWSCAN_WARN)
 134                         warnx("%s > max gid value (%lu)", p, ULONG_MAX);
 135                 return (0);
 136         }
 137         if (*ep != '\0') {
 138                 if (flags & _PWSCAN_WARN)
 139                         warnx("%s gid is incorrect", p);
 140                 return (0);
 141         }
 142         if (flags & _PWSCAN_WARN && pw_big_ids_warning && id > USHRT_MAX) {
 143                 warnx("%s > recommended max gid value (%u)", p, USHRT_MAX);
 144                 /* return (0); This should not be fatal! */
 145         }
 146         pw->pw_gid = id;
 147
 148         if (flags & _PWSCAN_MASTER ) {
 149                 if (!(pw->pw_class = strsep(&bp, ":"))) /* class */
 150                         goto fmt;
 151                 if (pw->pw_class[0])
 152                         pw->pw_fields |= _PWF_CLASS;
 153
 154                 if (!(p = strsep(&bp, ":")))            /* change */
 155                         goto fmt;
 156                 if (p[0])
 157                         pw->pw_fields |= _PWF_CHANGE;
 158                 pw->pw_change = atol(p);
 159
 160                 if (!(p = strsep(&bp, ":")))            /* expire */
 161                         goto fmt;
 162                 if (p[0])
 163                         pw->pw_fields |= _PWF_EXPIRE;
 164                 pw->pw_expire = atol(p);
 165         }
 166         if (!(pw->pw_gecos = strsep(&bp, ":")))         /* gecos */
 167                 goto fmt;
 168         if (pw->pw_gecos[0])
 169                 pw->pw_fields |= _PWF_GECOS;
 170
 171         if (!(pw->pw_dir = strsep(&bp, ":")))           /* directory */
 172                 goto fmt;
 173         if (pw->pw_dir[0])
 174                 pw->pw_fields |= _PWF_DIR;
 175
 176         if (!(pw->pw_shell = strsep(&bp, ":")))         /* shell */
 177                 goto fmt;
 178
 179         p = pw->pw_shell;
 180         if (root && *p) {                               /* empty == /bin/sh */
 181                 for (setusershell();;) {
 182                         if (!(sh = getusershell())) {
 183                                 if (flags & _PWSCAN_WARN)
 184                                         warnx("warning, unknown root shell");
 185                                 break;
 186                         }
 187                         if (!strcmp(p, sh))
 188                                 break;
 189                 }
 190                 endusershell();
 191         }
 192         if (p[0])
 193                 pw->pw_fields |= _PWF_SHELL;
 194
 195         if ((p = strsep(&bp, ":"))) {                   /* too many */
 196 fmt:
 197                 if (flags & _PWSCAN_WARN)
 198                         warnx("corrupted entry");
 199                 return (0);
 200         }
 201         return (1);
 202 }