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 2007 Sun Microsystems, Inc.  All rights reserved.
  23  * Use is subject to license terms.
  24  */
  25 
  26 /*      Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T     */
  27 /*        All Rights Reserved   */
  28 
  29 
  30 #pragma ident   "%Z%%M% %I%     %E% SMI"
  31 
  32 #include <sys/types.h>
  33 #include <sys/param.h>
  34 #include <sys/signal.h>
  35 #include <sys/sysmacros.h>
  36 #include <sys/stat.h>
  37 #include <stdio.h>
  38 #include <stdlib.h>
  39 #include <string.h>
  40 #include <ctype.h>
  41 #include <locale.h>
  42 #include <errno.h>
  43 #include <unistd.h>
  44 
  45 #define ERROR1  "Too many/few fields"
  46 #define ERROR2  "Bad character(s) in logname"
  47 #define ERROR2a "First char in logname not alphabetic"
  48 #define ERROR2b "Logname field NULL"
  49 #define ERROR2c "Logname contains no lower-case letters"
  50 #define ERROR3  "Logname too long/short"
  51 #define ERROR4  "Invalid UID"
  52 #define ERROR5  "Invalid GID"
  53 #define ERROR6  "Login directory not found"
  54 #define ERROR6a "Login directory null"
  55 #define ERROR7  "Optional shell file not found"
  56 
  57 static int eflag, code = 0;
  58 static int badc;
  59 static int lc;
  60 static char buf[512];
  61 static void error(char *);
  62 
  63 int
  64 main(int argc, char **argv)
  65 {
  66         int delim[512];
  67         char logbuf[512];
  68         FILE *fptr;
  69         struct stat obuf;
  70         uid_t uid;
  71         gid_t gid;
  72         int i, j, colons;
  73         char *pw_file;
  74         struct stat stat_buf;
  75         char *str, *lastc;
  76 
  77         (void) setlocale(LC_ALL, "");
  78 
  79 #if !defined(TEXT_DOMAIN)       /* Should be defined by cc -D */
  80 #define TEXT_DOMAIN "SYS_TEST"
  81 #endif
  82         (void) textdomain(TEXT_DOMAIN);
  83 
  84         if (argc == 1)
  85                 pw_file = "/etc/passwd";
  86         else
  87                 pw_file = argv[1];
  88 
  89         if ((fptr = fopen(pw_file, "r")) == NULL) {
  90                 (void) fprintf(stderr, gettext("cannot open %s\n"), pw_file);
  91                 exit(1);
  92         }
  93 
  94         if (fstat(fileno(fptr), &stat_buf) < 0) {
  95                 (void) fprintf(stderr, gettext("fstat failed for %s\n"),
  96                     pw_file);
  97                 (void) fclose(fptr);
  98                 exit(1);
  99         }
 100 
 101         if (stat_buf.st_size == 0) {
 102                 (void) fprintf(stderr, gettext("file %s is empty\n"), pw_file);
 103                 (void) fclose(fptr);
 104                 exit(1);
 105         }
 106 
 107         while (fgets(buf, sizeof (buf), fptr) != NULL) {
 108 
 109                 colons = 0;
 110                 badc = 0;
 111                 lc = 0;
 112                 eflag = 0;
 113 
 114                 /* Check that entry is not a nameservice redirection */
 115 
 116                 if (buf[0] == '+' || buf[0] == '-')  {
 117                         /*
 118                          * Should set flag here to allow special case checking
 119                          * in the rest of the code,
 120                          * but for now, we'll just ignore this entry.
 121                          */
 122                         continue;
 123                 }
 124 
 125                 /* Check number of fields */
 126 
 127                 for (i = 0; buf[i] != NULL; i++)
 128                         if (buf[i] == ':') {
 129                                 delim[colons] = i;
 130                                 ++colons;
 131                         }
 132 
 133                 if (colons != 6) {
 134                         error(ERROR1);
 135                         continue;
 136                 }
 137                 delim[6] = i - 1;
 138                 delim[7] = NULL;
 139 
 140                 /*
 141                  * Check the first char is alpha; the rest alphanumeric;
 142                  * and that the name does not consist solely of uppercase
 143                  * alpha chars
 144                  */
 145                 if (buf[0] == ':')
 146                         error(ERROR2b);
 147                 else if (!isalpha(buf[0]))
 148                         error(ERROR2a);
 149 
 150                 for (i = 0; buf[i] != ':'; i++) {
 151                         if (!isalnum(buf[i]) &&
 152                                 buf[i] != '_' &&
 153                                 buf[i] != '-' &&
 154                                 buf[i] != '.')
 155                                 badc++;
 156                         else if (islower(buf[i]))
 157                                 lc++;
 158                 }
 159                 if (lc == 0)
 160                         error(ERROR2c);
 161                 if (badc > 0)
 162                         error(ERROR2);
 163 
 164                 /* Check for valid number of characters in logname */
 165 
 166                 if (i <= 0 || i > 8)
 167                         error(ERROR3);
 168 
 169                 /* Check that UID is numeric and <= MAXUID */
 170 
 171                 errno = 0;
 172                 str = &buf[delim[1] + 1];
 173                 uid = strtol(str, &lastc, 10);
 174                 if (lastc != str + (delim[2] - delim[1]) - 1 ||
 175                     uid > MAXUID || errno == ERANGE)
 176                         error(ERROR4);
 177 
 178                 /* Check that GID is numeric and <= MAXUID */
 179 
 180                 errno = 0;
 181                 str = &buf[delim[2] + 1];
 182                 gid = strtol(str, &lastc, 10);
 183                 if (lastc != str + (delim[3] - delim[2]) - 1 ||
 184                     gid > MAXUID || errno == ERANGE)
 185                         error(ERROR5);
 186 
 187                 /* Check initial working directory */
 188 
 189                 for (j = 0, i = (delim[4] + 1); i < delim[5]; j++, i++)
 190                         logbuf[j] = buf[i];
 191                 logbuf[j] = '\0';
 192 
 193                 if (logbuf[0] == NULL)
 194                         error(ERROR6a);
 195                 else if ((stat(logbuf, &obuf)) == -1)
 196                         error(ERROR6);
 197 
 198                 /* Check program to use as shell  */
 199 
 200                 if ((buf[(delim[5] + 1)]) != '\n') {
 201 
 202                         for (j = 0, i = (delim[5] + 1); i < delim[6]; j++, i++)
 203                                 logbuf[j] = buf[i];
 204                         logbuf[j] = '\0';
 205 
 206                         if (strcmp(logbuf, "*") == 0)   /* subsystem login */
 207                                 continue;
 208 
 209                         if ((stat(logbuf, &obuf)) == -1)
 210                                 error(ERROR7);
 211 
 212                         for (j = 0; j < 512; j++)
 213                                 logbuf[j] = NULL;
 214                 }
 215         }
 216         (void) fclose(fptr);
 217         return (code);
 218 }
 219 
 220 /* Error printing routine */
 221 
 222 static void
 223 error(char *msg)
 224 {
 225         if (!eflag) {
 226                 (void) fprintf(stderr, "\n%s", buf);
 227                 code = 1;
 228                 ++eflag;
 229         }
 230         if (!badc)
 231                 (void) fprintf(stderr, "\t%s\n", gettext(msg));
 232         else {
 233                 (void) fprintf(stderr, "\t%d %s\n", badc, gettext(msg));
 234                 badc = 0;
 235         }
 236 }