usr.bin/chpass/field.c

   1 /*-
   2  * SPDX-License-Identifier: BSD-4-Clause
   3  *
   4  * Copyright (c) 1988, 1993, 1994
   5  *      The Regents of the University of California.  All rights reserved.
   6  * Copyright (c) 2002 Networks Associates Technology, Inc.
   7  * All rights reserved.
   8  *
   9  * Portions of this software were developed for the FreeBSD Project by
  10  * ThinkSec AS and NAI Labs, the Security Research Division of Network
  11  * Associates, Inc.  under DARPA/SPAWAR contract N66001-01-C-8035
  12  * ("CBOSS"), as part of the DARPA CHATS research program.
  13  *
  14  * Redistribution and use in source and binary forms, with or without
  15  * modification, are permitted provided that the following conditions
  16  * are met:
  17  * 1. Redistributions of source code must retain the above copyright
  18  *    notice, this list of conditions and the following disclaimer.
  19  * 2. Redistributions in binary form must reproduce the above copyright
  20  *    notice, this list of conditions and the following disclaimer in the
  21  *    documentation and/or other materials provided with the distribution.
  22  * 3. All advertising materials mentioning features or use of this software
  23  *    must display the following acknowledgement:
  24  *      This product includes software developed by the University of
  25  *      California, Berkeley and its contributors.
  26  * 4. Neither the name of the University nor the names of its contributors
  27  *    may be used to endorse or promote products derived from this software
  28  *    without specific prior written permission.
  29  *
  30  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  31  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  32  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  33  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  34  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  35  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  36  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  37  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  38  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  39  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  40  * SUCH DAMAGE.
  41  */
  42
  43 #include <sys/param.h>
  44 #include <sys/stat.h>
  45
  46 #include <ctype.h>
  47 #include <err.h>
  48 #include <errno.h>
  49 #include <grp.h>
  50 #include <paths.h>
  51 #include <pwd.h>
  52 #include <stdlib.h>
  53 #include <string.h>
  54
  55 #include "chpass.h"
  56
  57 /* ARGSUSED */
  58 int
  59 p_login(char *p, struct passwd *pw, ENTRY *ep __unused)
  60 {
  61         if (!*p) {
  62                 warnx("empty login field");
  63                 return (-1);
  64         }
  65         if (*p == '-') {
  66                 warnx("login names may not begin with a hyphen");
  67                 return (-1);
  68         }
  69         if (!(pw->pw_name = strdup(p))) {
  70                 warnx("can't save entry");
  71                 return (-1);
  72         }
  73         if (strchr(p, '.'))
  74                 warnx("\'.\' is dangerous in a login name");
  75         for (; *p; ++p)
  76                 if (isupper(*p)) {
  77                         warnx("upper-case letters are dangerous in a login name");
  78                         break;
  79                 }
  80         return (0);
  81 }
  82
  83 /* ARGSUSED */
  84 int
  85 p_passwd(char *p, struct passwd *pw, ENTRY *ep __unused)
  86 {
  87         if (!(pw->pw_passwd = strdup(p))) {
  88                 warnx("can't save password entry");
  89                 return (-1);
  90         }
  91
  92         return (0);
  93 }
  94
  95 /* ARGSUSED */
  96 int
  97 p_uid(char *p, struct passwd *pw, ENTRY *ep __unused)
  98 {
  99         uid_t id;
 100         char *np;
 101
 102         if (!*p) {
 103                 warnx("empty uid field");
 104                 return (-1);
 105         }
 106         if (!isdigit(*p)) {
 107                 warnx("illegal uid");
 108                 return (-1);
 109         }
 110         errno = 0;
 111         id = strtoul(p, &np, 10);
 112         if (*np || (id == (uid_t)ULONG_MAX && errno == ERANGE)) {
 113                 warnx("illegal uid");
 114                 return (-1);
 115         }
 116         pw->pw_uid = id;
 117         return (0);
 118 }
 119
 120 /* ARGSUSED */
 121 int
 122 p_gid(char *p, struct passwd *pw, ENTRY *ep __unused)
 123 {
 124         struct group *gr;
 125         gid_t id;
 126         char *np;
 127
 128         if (!*p) {
 129                 warnx("empty gid field");
 130                 return (-1);
 131         }
 132         if (!isdigit(*p)) {
 133                 if (!(gr = getgrnam(p))) {
 134                         warnx("unknown group %s", p);
 135                         return (-1);
 136                 }
 137                 pw->pw_gid = gr->gr_gid;
 138                 return (0);
 139         }
 140         errno = 0;
 141         id = strtoul(p, &np, 10);
 142         if (*np || (id == (uid_t)ULONG_MAX && errno == ERANGE)) {
 143                 warnx("illegal gid");
 144                 return (-1);
 145         }
 146         pw->pw_gid = id;
 147         return (0);
 148 }
 149
 150 /* ARGSUSED */
 151 int
 152 p_class(char *p, struct passwd *pw, ENTRY *ep __unused)
 153 {
 154         if (!(pw->pw_class = strdup(p))) {
 155                 warnx("can't save entry");
 156                 return (-1);
 157         }
 158
 159         return (0);
 160 }
 161
 162 /* ARGSUSED */
 163 int
 164 p_change(char *p, struct passwd *pw, ENTRY *ep __unused)
 165 {
 166         if (!atot(p, &pw->pw_change))
 167                 return (0);
 168         warnx("illegal date for change field");
 169         return (-1);
 170 }
 171
 172 /* ARGSUSED */
 173 int
 174 p_expire(char *p, struct passwd *pw, ENTRY *ep __unused)
 175 {
 176         if (!atot(p, &pw->pw_expire))
 177                 return (0);
 178         warnx("illegal date for expire field");
 179         return (-1);
 180 }
 181
 182 /* ARGSUSED */
 183 int
 184 p_gecos(char *p, struct passwd *pw __unused, ENTRY *ep)
 185 {
 186         if (!(ep->save = strdup(p))) {
 187                 warnx("can't save entry");
 188                 return (-1);
 189         }
 190         return (0);
 191 }
 192
 193 /* ARGSUSED */
 194 int
 195 p_hdir(char *p, struct passwd *pw, ENTRY *ep __unused)
 196 {
 197         if (!*p) {
 198                 warnx("empty home directory field");
 199                 return (-1);
 200         }
 201         if (!(pw->pw_dir = strdup(p))) {
 202                 warnx("can't save entry");
 203                 return (-1);
 204         }
 205         return (0);
 206 }
 207
 208 /* ARGSUSED */
 209 int
 210 p_shell(char *p, struct passwd *pw, ENTRY *ep __unused)
 211 {
 212         struct stat sbuf;
 213
 214         if (!*p) {
 215                 pw->pw_shell = strdup(_PATH_BSHELL);
 216                 return (0);
 217         }
 218         /* only admin can change from or to "restricted" shells */
 219         if (!master_mode && pw->pw_shell && !ok_shell(pw->pw_shell)) {
 220                 warnx("%s: current shell non-standard", pw->pw_shell);
 221                 return (-1);
 222         }
 223         if (!ok_shell(p)) {
 224                 if (!master_mode) {
 225                         warnx("%s: non-standard shell", p);
 226                         return (-1);
 227                 }
 228                 pw->pw_shell = strdup(p);
 229         }
 230         else
 231                 pw->pw_shell = dup_shell(p);
 232         if (!pw->pw_shell) {
 233                 warnx("can't save entry");
 234                 return (-1);
 235         }
 236         if (stat(pw->pw_shell, &sbuf) < 0) {
 237                 if (errno == ENOENT)
 238                         warnx("WARNING: shell '%s' does not exist",
 239                             pw->pw_shell);
 240                 else
 241                         warn("WARNING: can't stat shell '%s'",  pw->pw_shell);
 242                 return (0);
 243         }
 244         if (!S_ISREG(sbuf.st_mode)) {
 245                 warnx("WARNING: shell '%s' is not a regular file",
 246                         pw->pw_shell);
 247                 return (0);
 248         }
 249         if ((sbuf.st_mode & (S_IXOTH | S_IXGRP | S_IXUSR)) == 0) {
 250                 warnx("WARNING: shell '%s' is not executable", pw->pw_shell);
 251                 return (0);
 252         }
 253         return (0);
 254 }