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
  30 #if defined(LIBC_SCCS) && !defined(lint)
  31 static char sccsid[] = "@(#)pw_scan.c   8.3 (Berkeley) 4/2/94";
  32 #endif /* LIBC_SCCS and not lint */
  33 #include <sys/cdefs.h>
  34 __FBSDID("$FreeBSD$");
  35
  36 /*
  37  * This module is used to "verify" password entries by chpass(1) and
  38  * pwd_mkdb(8).
  39  */
  40
  41 #include <sys/param.h>
  42
  43 #include <err.h>
  44 #include <errno.h>
  45 #include <fcntl.h>
  46 #include <pwd.h>
  47 #include <stdio.h>
  48 #include <string.h>
  49 #include <stdlib.h>
  50 #include <unistd.h>
  51
  52 #include "pw_scan.h"
  53
  54 /*
  55  * Some software assumes that IDs are short.  We should emit warnings
  56  * for id's which cannot be stored in a short, but we are more liberal
  57  * by default, warning for IDs greater than USHRT_MAX.
  58  *
  59  * If pw_big_ids_warning is -1 on entry to pw_scan(), it will be set based
  60  * on the existence of PW_SCAN_BIG_IDS in the environment.
  61  */
  62 static int      pw_big_ids_warning = -1;
  63
  64 int
  65 __pw_scan(char *bp, struct passwd *pw, int flags)
  66 {
  67         uid_t id;
  68         int root;
  69         char *ep, *p, *sh;
  70
  71         if (pw_big_ids_warning == -1)
  72                 pw_big_ids_warning = getenv("PW_SCAN_BIG_IDS") == NULL ? 1 : 0;
  73
  74         pw->pw_fields = 0;
  75         if (!(pw->pw_name = strsep(&bp, ":")))          /* login */
  76                 goto fmt;
  77         root = !strcmp(pw->pw_name, "root");
  78         if (pw->pw_name[0] && (pw->pw_name[0] != '+' || pw->pw_name[1] == '\0'))
  79                 pw->pw_fields |= _PWF_NAME;
  80
  81         if (!(pw->pw_passwd = strsep(&bp, ":")))        /* passwd */
  82                 goto fmt;
  83         if (pw->pw_passwd[0])
  84                 pw->pw_fields |= _PWF_PASSWD;
  85
  86         if (!(p = strsep(&bp, ":")))                    /* uid */
  87                 goto fmt;
  88         if (p[0])
  89                 pw->pw_fields |= _PWF_UID;
  90         else {
  91                 if (pw->pw_name[0] != '+' && pw->pw_name[0] != '-') {
  92                         if (flags & _PWSCAN_WARN)
  93                                 warnx("no uid for user %s", pw->pw_name);
  94                         return (0);
  95                 }
  96         }
  97         id = strtoul(p, &ep, 10);
  98         if (errno == ERANGE) {
  99                 if (flags & _PWSCAN_WARN)
 100                         warnx("%s > max uid value (%lu)", p, ULONG_MAX);
 101                 return (0);
 102         }
 103         if (*ep != '\0') {
 104                 if (flags & _PWSCAN_WARN)
 105                         warnx("%s uid is incorrect", p);
 106                 return (0);
 107         }
 108         if (root && id) {
 109                 if (flags & _PWSCAN_WARN)
 110                         warnx("root uid should be 0");
 111                 return (0);
 112         }
 113         if (flags & _PWSCAN_WARN && pw_big_ids_warning && id > USHRT_MAX) {
 114                 warnx("%s > recommended max uid value (%u)", p, USHRT_MAX);
 115                 /*return (0);*/ /* THIS SHOULD NOT BE FATAL! */
 116         }
 117         pw->pw_uid = id;
 118
 119         if (!(p = strsep(&bp, ":")))                    /* gid */
 120                 goto fmt;
 121         if (p[0])
 122                 pw->pw_fields |= _PWF_GID;
 123         else {
 124                 if (pw->pw_name[0] != '+' && pw->pw_name[0] != '-') {
 125                         if (flags & _PWSCAN_WARN)
 126                                 warnx("no gid for user %s", pw->pw_name);
 127                         return (0);
 128                 }
 129         }
 130         id = strtoul(p, &ep, 10);
 131         if (errno == ERANGE) {
 132                 if (flags & _PWSCAN_WARN)
 133                         warnx("%s > max gid value (%lu)", p, ULONG_MAX);
 134                 return (0);
 135         }
 136         if (*ep != '\0') {
 137                 if (flags & _PWSCAN_WARN)
 138                         warnx("%s gid is incorrect", p);
 139                 return (0);
 140         }
 141         if (flags & _PWSCAN_WARN && pw_big_ids_warning && id > USHRT_MAX) {
 142                 warnx("%s > recommended max gid value (%u)", p, USHRT_MAX);
 143                 /* return (0); This should not be fatal! */
 144         }
 145         pw->pw_gid = id;
 146
 147         if (flags & _PWSCAN_MASTER ) {
 148                 if (!(pw->pw_class = strsep(&bp, ":"))) /* class */
 149                         goto fmt;
 150                 if (pw->pw_class[0])
 151                         pw->pw_fields |= _PWF_CLASS;
 152
 153                 if (!(p = strsep(&bp, ":")))            /* change */
 154                         goto fmt;
 155                 if (p[0])
 156                         pw->pw_fields |= _PWF_CHANGE;
 157                 pw->pw_change = atol(p);
 158
 159                 if (!(p = strsep(&bp, ":")))            /* expire */
 160                         goto fmt;
 161                 if (p[0])
 162                         pw->pw_fields |= _PWF_EXPIRE;
 163                 pw->pw_expire = atol(p);
 164         }
 165         if (!(pw->pw_gecos = strsep(&bp, ":")))         /* gecos */
 166                 goto fmt;
 167         if (pw->pw_gecos[0])
 168                 pw->pw_fields |= _PWF_GECOS;
 169
 170         if (!(pw->pw_dir = strsep(&bp, ":")))           /* directory */
 171                 goto fmt;
 172         if (pw->pw_dir[0])
 173                 pw->pw_fields |= _PWF_DIR;
 174
 175         if (!(pw->pw_shell = strsep(&bp, ":")))         /* shell */
 176                 goto fmt;
 177
 178         p = pw->pw_shell;
 179         if (root && *p) {                               /* empty == /bin/sh */
 180                 for (setusershell();;) {
 181                         if (!(sh = getusershell())) {
 182                                 if (flags & _PWSCAN_WARN)
 183                                         warnx("warning, unknown root shell");
 184                                 break;
 185                         }
 186                         if (!strcmp(p, sh))
 187                                 break;
 188                 }
 189                 endusershell();
 190         }
 191         if (p[0])
 192                 pw->pw_fields |= _PWF_SHELL;
 193
 194         if ((p = strsep(&bp, ":"))) {                   /* too many */
 195 fmt:
 196                 if (flags & _PWSCAN_WARN)
 197                         warnx("corrupted entry");
 198                 return (0);
 199         }
 200         return (1);
 201 }