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, Version 1.0 only
   6  * (the "License").  You may not use this file except in compliance
   7  * with the License.
   8  *
   9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
  10  * or http://www.opensolaris.org/os/licensing.
  11  * See the License for the specific language governing permissions
  12  * and limitations under the License.
  13  *
  14  * When distributing Covered Code, include this CDDL HEADER in each
  15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  16  * If applicable, add the following below this CDDL HEADER, with the
  17  * fields enclosed by brackets "[]" replaced with your own identifying
  18  * information: Portions Copyright [yyyy] [name of copyright owner]
  19  *
  20  * CDDL HEADER END
  21  */
  22 /*
  23  * Copyright (c) 2013 Gary Mills
  24  *
  25  * Copyright (c) 1997, by Sun Microsystems, Inc.
  26  * All rights reserved.
  27  */
  28 
  29 /*      Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T     */
  30 /*        All Rights Reserved   */
  31 
  32 /*LINTLIBRARY*/
  33 
  34 #include        <sys/types.h>
  35 #include        <stdio.h>
  36 #include        <ctype.h>
  37 #include        <userdefs.h>
  38 #include        <users.h>
  39 #include        <deflt.h>
  40 #include        <limits.h>
  41 
  42 /* Defaults file */
  43 #define DEFAULT_USERADD "/etc/default/useradd"
  44 
  45 /* Traditional length limit */
  46 #define TRAD_LEN_MAX    8
  47 
  48 /*
  49  * validate string given as login name.
  50  */
  51 int
  52 valid_login(char *login, struct passwd **pptr, int *warning)
  53 {
  54         struct passwd *t_pptr;
  55         char *ptr = login;
  56         int bad1char, badc, clower, len;
  57         char c;
  58         char action;
  59 
  60         len = 0; clower = 0; badc = 0; bad1char = 0;
  61         *warning = 0;
  62         if (!login || !*login)
  63                 return (INVALID);
  64 
  65         c = *ptr;
  66         if (!isalpha(c))
  67                 bad1char++;
  68         for (; c != NULL; ptr++, c = *ptr) {
  69                 len++;
  70                 if (!isprint(c) || (c == ':') || (c == '\n'))
  71                         return (INVALID);
  72                 if (!isalnum(c) && c != '_' && c != '-' && c != '.')
  73                         badc++;
  74                 if (islower(c))
  75                         clower++;
  76         }
  77 
  78         action = 'w';
  79         if (defopen(DEFAULT_USERADD) == 0) {
  80                 char *defptr;
  81 
  82                 if ((defptr = defread("EXCEED_TRAD=")) != NULL) {
  83                         char let = tolower(*defptr);
  84 
  85                         switch (let) {
  86                         case 'w':       /* warning */
  87                         case 'e':       /* error */
  88                         case 's':       /* silent */
  89                                 action = let;
  90                                 break;
  91                         }
  92                 }
  93                 (void) defopen((char *)NULL);
  94         }
  95 
  96         if (len > LOGNAME_MAX)
  97                 return (LONGNAME);
  98 
  99         if (len > TRAD_LEN_MAX) {
 100                 if (action == 'w')
 101                         *warning = *warning | WARN_NAME_TOO_LONG;
 102                 else if (action == 'e')
 103                         return (LONGNAME);
 104         }
 105 
 106         if (clower == 0)
 107                 *warning = *warning | WARN_NO_LOWERCHAR;
 108         if (badc != 0)
 109                 *warning = *warning | WARN_BAD_LOGNAME_CHAR;
 110         if (bad1char != 0)
 111                 *warning = *warning | WARN_BAD_LOGNAME_FIRST;
 112 
 113         if ((t_pptr = getpwnam(login)) != NULL) {
 114                 if (pptr) *pptr = t_pptr;
 115                 return (NOTUNIQUE);
 116         }
 117         return (UNIQUE);
 118 }