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 (c) 2013 Gary Mills
  23  *
  24  * Copyright 2007 Sun Microsystems, Inc.  All rights reserved.
  25  * Use is subject to license terms.
  26  */
  27 
  28 /*      Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T     */
  29 /*        All Rights Reserved   */
  30 
  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 #include <limits.h>
  45 
  46 #define ERROR1  "Too many/few fields"
  47 #define ERROR2  "Bad character(s) in logname"
  48 #define ERROR2a "First char in logname not alphabetic"
  49 #define ERROR2b "Logname field NULL"
  50 #define ERROR2c "Logname contains no lower-case letters"
  51 #define ERROR3  "Logname too long/short"
  52 #define ERROR4  "Invalid UID"
  53 #define ERROR5  "Invalid GID"
  54 #define ERROR6  "Login directory not found"
  55 #define ERROR6a "Login directory null"
  56 #define ERROR7  "Optional shell file not found"
  57 
  58 static int eflag, code = 0;
  59 static int badc;
  60 static int lc;
  61 static char buf[512];
  62 static void error(char *);
  63 
  64 int
  65 main(int argc, char **argv)
  66 {
  67         int delim[512];
  68         char logbuf[512];
  69         FILE *fptr;
  70         struct stat obuf;
  71         uid_t uid;
  72         gid_t gid;
  73         int i, j, colons;
  74         char *pw_file;
  75         struct stat stat_buf;
  76         char *str, *lastc;
  77 
  78         (void) setlocale(LC_ALL, "");
  79 
  80 #if !defined(TEXT_DOMAIN)       /* Should be defined by cc -D */
  81 #define TEXT_DOMAIN "SYS_TEST"
  82 #endif
  83         (void) textdomain(TEXT_DOMAIN);
  84 
  85         if (argc == 1)
  86                 pw_file = "/etc/passwd";
  87         else
  88                 pw_file = argv[1];
  89 
  90         if ((fptr = fopen(pw_file, "r")) == NULL) {
  91                 (void) fprintf(stderr, gettext("cannot open %s\n"), pw_file);
  92                 exit(1);
  93         }
  94 
  95         if (fstat(fileno(fptr), &stat_buf) < 0) {
  96                 (void) fprintf(stderr, gettext("fstat failed for %s\n"),
  97                     pw_file);
  98                 (void) fclose(fptr);
  99                 exit(1);
 100         }
 101 
 102         if (stat_buf.st_size == 0) {
 103                 (void) fprintf(stderr, gettext("file %s is empty\n"), pw_file);
 104                 (void) fclose(fptr);
 105                 exit(1);
 106         }
 107 
 108         while (fgets(buf, sizeof (buf), fptr) != NULL) {
 109 
 110                 colons = 0;
 111                 badc = 0;
 112                 lc = 0;
 113                 eflag = 0;
 114 
 115                 /* Check that entry is not a nameservice redirection */
 116 
 117                 if (buf[0] == '+' || buf[0] == '-')  {
 118                         /*
 119                          * Should set flag here to allow special case checking
 120                          * in the rest of the code,
 121                          * but for now, we'll just ignore this entry.
 122                          */
 123                         continue;
 124                 }
 125 
 126                 /* Check number of fields */
 127 
 128                 for (i = 0; buf[i] != NULL; i++)
 129                         if (buf[i] == ':') {
 130                                 delim[colons] = i;
 131                                 ++colons;
 132                         }
 133 
 134                 if (colons != 6) {
 135                         error(ERROR1);
 136                         continue;
 137                 }
 138                 delim[6] = i - 1;
 139                 delim[7] = NULL;
 140 
 141                 /*
 142                  * Check the first char is alpha; the rest alphanumeric;
 143                  * and that the name does not consist solely of uppercase
 144                  * alpha chars
 145                  */
 146                 if (buf[0] == ':')
 147                         error(ERROR2b);
 148                 else if (!isalpha(buf[0]))
 149                         error(ERROR2a);
 150 
 151                 for (i = 0; buf[i] != ':'; i++) {
 152                         if (!isalnum(buf[i]) &&
 153                             buf[i] != '_' &&
 154                             buf[i] != '-' &&
 155                             buf[i] != '.')
 156                                 badc++;
 157                         else if (islower(buf[i]))
 158                                 lc++;
 159                 }
 160                 if (lc == 0)
 161                         error(ERROR2c);
 162                 if (badc > 0)
 163                         error(ERROR2);
 164 
 165                 /* Check for valid number of characters in logname */
 166 
 167                 if (i <= 0 || i > LOGNAME_MAX_ILLUMOS)
 168                         error(ERROR3);
 169 
 170                 /* Check that UID is numeric and <= MAXUID */
 171 
 172                 errno = 0;
 173                 str = &buf[delim[1] + 1];
 174                 uid = strtol(str, &lastc, 10);
 175                 if (lastc != str + (delim[2] - delim[1]) - 1 ||
 176                     uid > MAXUID || errno == ERANGE)
 177                         error(ERROR4);
 178 
 179                 /* Check that GID is numeric and <= MAXUID */
 180 
 181                 errno = 0;
 182                 str = &buf[delim[2] + 1];
 183                 gid = strtol(str, &lastc, 10);
 184                 if (lastc != str + (delim[3] - delim[2]) - 1 ||
 185                     gid > MAXUID || errno == ERANGE)
 186                         error(ERROR5);
 187 
 188                 /* Check initial working directory */
 189 
 190                 for (j = 0, i = (delim[4] + 1); i < delim[5]; j++, i++)
 191                         logbuf[j] = buf[i];
 192                 logbuf[j] = '\0';
 193 
 194                 if (logbuf[0] == NULL)
 195                         error(ERROR6a);
 196                 else if ((stat(logbuf, &obuf)) == -1)
 197                         error(ERROR6);
 198 
 199                 /* Check program to use as shell  */
 200 
 201                 if ((buf[(delim[5] + 1)]) != '\n') {
 202 
 203                         for (j = 0, i = (delim[5] + 1); i < delim[6]; j++, i++)
 204                                 logbuf[j] = buf[i];
 205                         logbuf[j] = '\0';
 206 
 207                         if (strcmp(logbuf, "*") == 0)   /* subsystem login */
 208                                 continue;
 209 
 210                         if ((stat(logbuf, &obuf)) == -1)
 211                                 error(ERROR7);
 212 
 213                         for (j = 0; j < 512; j++)
 214                                 logbuf[j] = NULL;
 215                 }
 216         }
 217         (void) fclose(fptr);
 218         return (code);
 219 }
 220 
 221 /* Error printing routine */
 222 
 223 static void
 224 error(char *msg)
 225 {
 226         if (!eflag) {
 227                 (void) fprintf(stderr, "\n%s", buf);
 228                 code = 1;
 229                 ++eflag;
 230         }
 231         if (!badc)
 232                 (void) fprintf(stderr, "\t%s\n", gettext(msg));
 233         else {
 234                 (void) fprintf(stderr, "\t%d %s\n", badc, gettext(msg));
 235                 badc = 0;
 236         }
 237 }