usr.bin/chpass/edit.c

   1 /*-
   2  * Copyright (c) 1990, 1993, 1994
   3  *      The Regents of the University of California.  All rights reserved.
   4  * Copyright (c) 2002 Networks Associates Technology, Inc.
   5  * All rights reserved.
   6  *
   7  * Portions of this software were developed for the FreeBSD Project by
   8  * ThinkSec AS and NAI Labs, the Security Research Division of Network
   9  * Associates, Inc.  under DARPA/SPAWAR contract N66001-01-C-8035
  10  * ("CBOSS"), as part of the DARPA CHATS research program.
  11  *
  12  * Redistribution and use in source and binary forms, with or without
  13  * modification, are permitted provided that the following conditions
  14  * are met:
  15  * 1. Redistributions of source code must retain the above copyright
  16  *    notice, this list of conditions and the following disclaimer.
  17  * 2. Redistributions in binary form must reproduce the above copyright
  18  *    notice, this list of conditions and the following disclaimer in the
  19  *    documentation and/or other materials provided with the distribution.
  20  * 3. Neither the name of the University nor the names of its contributors
  21  *    may be used to endorse or promote products derived from this software
  22  *    without specific prior written permission.
  23  *
  24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  34  * SUCH DAMAGE.
  35  *
  36  * @(#)edit.c   8.3 (Berkeley) 4/2/94
  37  * $FreeBSD: src/usr.bin/chpass/edit.c,v 1.23 2003/04/09 18:18:42 des Exp $
  38  * $DragonFly: src/usr.bin/chpass/edit.c,v 1.3 2003/10/02 17:42:26 hmp Exp $
  39  */
  40
  41 #include <sys/param.h>
  42 #include <sys/stat.h>
  43
  44 #include <ctype.h>
  45 #include <err.h>
  46 #include <errno.h>
  47 #include <paths.h>
  48 #include <pwd.h>
  49 #include <stdio.h>
  50 #include <stdlib.h>
  51 #include <string.h>
  52 #include <unistd.h>
  53
  54 #include <pw_scan.h>
  55 #include <libutil.h>
  56
  57 #include "chpass.h"
  58
  59 static int display(const char *tfn, struct passwd *pw);
  60 static struct passwd *verify(const char *tfn, struct passwd *pw);
  61
  62 struct passwd *
  63 edit(const char *tfn, struct passwd *pw)
  64 {
  65         struct passwd *npw;
  66         char *line;
  67         size_t len;
  68
  69         if (display(tfn, pw) == -1)
  70                 return (NULL);
  71         for (;;) {
  72                 switch (pw_edit(1)) {
  73                 case -1:
  74                         return (NULL);
  75                 case 0:
  76                         return (pw_dup(pw));
  77                 default:
  78                         break;
  79                 }
  80                 if ((npw = verify(tfn, pw)) != NULL)
  81                         return (npw);
  82                 free(npw);
  83                 printf("re-edit the password file? ");
  84                 fflush(stdout);
  85                 if ((line = fgetln(stdin, &len)) == NULL) {
  86                         warn("fgetln()");
  87                         return (NULL);
  88                 }
  89                 if (len > 0 && (*line == 'N' || *line == 'n'))
  90                         return (NULL);
  91         }
  92 }
  93
  94 /*
  95  * display --
  96  *      print out the file for the user to edit; strange side-effect:
  97  *      set conditional flag if the user gets to edit the shell.
  98  */
  99 static int
 100 display(const char *tfn, struct passwd *pw)
 101 {
 102         FILE *fp;
 103         char *bp, *gecos, *p;
 104
 105         if ((fp = fopen(tfn, "w")) == NULL) {
 106                 warn("%s", tfn);
 107                 return (-1);
 108         }
 109
 110         fprintf(fp, "#Changing user information for %s.\n", pw->pw_name);
 111         if (master_mode) {
 112                 fprintf(fp, "Login: %s\n", pw->pw_name);
 113                 fprintf(fp, "Password: %s\n", pw->pw_passwd);
 114                 fprintf(fp, "Uid [#]: %lu\n", (unsigned long)pw->pw_uid);
 115                 fprintf(fp, "Gid [# or name]: %lu\n",
 116                     (unsigned long)pw->pw_gid);
 117                 fprintf(fp, "Change [month day year]: %s\n",
 118                     ttoa(pw->pw_change));
 119                 fprintf(fp, "Expire [month day year]: %s\n",
 120                     ttoa(pw->pw_expire));
 121                 fprintf(fp, "Class: %s\n", pw->pw_class);
 122                 fprintf(fp, "Home directory: %s\n", pw->pw_dir);
 123                 fprintf(fp, "Shell: %s\n",
 124                     *pw->pw_shell ? pw->pw_shell : _PATH_BSHELL);
 125         }
 126         /* Only admin can change "restricted" shells. */
 127 #if 0
 128         else if (ok_shell(pw->pw_shell))
 129                 /*
 130                  * Make shell a restricted field.  Ugly with a
 131                  * necklace, but there's not much else to do.
 132                  */
 133 #else
 134         else if ((!list[E_SHELL].restricted && ok_shell(pw->pw_shell)) ||
 135             master_mode)
 136                 /*
 137                  * If change not restrict (table.c) and standard shell
 138                  *      OR if root, then allow editing of shell.
 139                  */
 140 #endif
 141                 fprintf(fp, "Shell: %s\n",
 142                     *pw->pw_shell ? pw->pw_shell : _PATH_BSHELL);
 143         else
 144                 list[E_SHELL].restricted = 1;
 145
 146         if ((bp = gecos = strdup(pw->pw_gecos)) == NULL) {
 147                 warn(NULL);
 148                 fclose(fp);
 149                 return (-1);
 150         }
 151
 152         p = strsep(&bp, ",");
 153         p = strdup(p ? p : "");
 154         list[E_NAME].save = p;
 155         if (!list[E_NAME].restricted || master_mode)
 156                 fprintf(fp, "Full Name: %s\n", p);
 157
 158         p = strsep(&bp, ",");
 159         p = strdup(p ? p : "");
 160         list[E_LOCATE].save = p;
 161         if (!list[E_LOCATE].restricted || master_mode)
 162                 fprintf(fp, "Office Location: %s\n", p);
 163
 164         p = strsep(&bp, ",");
 165         p = strdup(p ? p : "");
 166         list[E_BPHONE].save = p;
 167         if (!list[E_BPHONE].restricted || master_mode)
 168                 fprintf(fp, "Office Phone: %s\n", p);
 169
 170         p = strsep(&bp, ",");
 171         p = strdup(p ? p : "");
 172         list[E_HPHONE].save = p;
 173         if (!list[E_HPHONE].restricted || master_mode)
 174                 fprintf(fp, "Home Phone: %s\n", p);
 175
 176         bp = strdup(bp ? bp : "");
 177         list[E_OTHER].save = bp;
 178         if (!list[E_OTHER].restricted || master_mode)
 179                 fprintf(fp, "Other information: %s\n", bp);
 180
 181         free(gecos);
 182
 183         fchown(fileno(fp), getuid(), getgid());
 184         fclose(fp);
 185         return (0);
 186 }
 187
 188 static struct passwd *
 189 verify(const char *tfn, struct passwd *pw)
 190 {
 191         struct passwd *npw;
 192         ENTRY *ep;
 193         char *buf, *p, *val;
 194         struct stat sb;
 195         FILE *fp;
 196         int line;
 197         size_t len;
 198
 199         if ((pw = pw_dup(pw)) == NULL)
 200                 return (NULL);
 201         if ((fp = fopen(tfn, "r")) == NULL ||
 202             fstat(fileno(fp), &sb) == -1) {
 203                 warn("%s", tfn);
 204                 free(pw);
 205                 return (NULL);
 206         }
 207         if (sb.st_size == 0) {
 208                 warnx("corrupted temporary file");
 209                 fclose(fp);
 210                 free(pw);
 211                 return (NULL);
 212         }
 213         val = NULL;
 214         for (line = 1; (buf = fgetln(fp, &len)) != NULL; ++line) {
 215                 if (*buf == '\0' || *buf == '#')
 216                         continue;
 217                 while (len > 0 && isspace(buf[len - 1]))
 218                         --len;
 219                 for (ep = list;; ++ep) {
 220                         if (!ep->prompt) {
 221                                 warnx("%s: unrecognized field on line %d",
 222                                     tfn, line);
 223                                 goto bad;
 224                         }
 225                         if (ep->len > len)
 226                                 continue;
 227                         if (strncasecmp(buf, ep->prompt, ep->len) != 0)
 228                                 continue;
 229                         if (ep->restricted && !master_mode) {
 230                                 warnx("%s: you may not change the %s field",
 231                                     tfn, ep->prompt);
 232                                 goto bad;
 233                         }
 234                         for (p = buf; p < buf + len && *p != ':'; ++p)
 235                                 /* nothing */ ;
 236                         if (*p != ':') {
 237                                 warnx("%s: line %d corrupted", tfn, line);
 238                                 goto bad;
 239                         }
 240                         while (++p < buf + len && isspace(*p))
 241                                 /* nothing */ ;
 242                         free(val);
 243                         asprintf(&val, "%.*s", (int)(buf + len - p), p);
 244                         if (val == NULL)
 245                                 goto bad;
 246                         if (ep->except && strpbrk(val, ep->except)) {
 247                                 warnx("%s: invalid character in \"%s\" field '%s'",
 248                                     tfn, ep->prompt, val);
 249                                 goto bad;
 250                         }
 251                         if ((ep->func)(val, pw, ep))
 252                                 goto bad;
 253                         break;
 254                 }
 255         }
 256         free(val);
 257         fclose(fp);
 258
 259         /* Build the gecos field. */
 260         len = asprintf(&p, "%s,%s,%s,%s,%s", list[E_NAME].save,
 261             list[E_LOCATE].save, list[E_BPHONE].save,
 262             list[E_HPHONE].save, list[E_OTHER].save);
 263         if (p == NULL) {
 264                 warn("asprintf()");
 265                 free(pw);
 266                 return (NULL);
 267         }
 268         while (len > 0 && p[len - 1] == ',')
 269                 p[--len] = '\0';
 270         pw->pw_gecos = p;
 271         buf = pw_make(pw);
 272         free(pw);
 273         free(p);
 274         if (buf == NULL) {
 275                 warn("pw_make()");
 276                 return (NULL);
 277         }
 278         npw = pw_scan(buf, PWSCAN_WARN|PWSCAN_MASTER);
 279         free(buf);
 280         return (npw);
 281 bad:
 282         free(pw);
 283         free(val);
 284         fclose(fp);
 285         return (NULL);
 286 }