usr.bin/passwd/local_passwd.c

   1 /*-
   2  * Copyright (c) 1990, 1993, 1994
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 3. All advertising materials mentioning features or use of this software
  14  *    must display the following acknowledgement:
  15  *      This product includes software developed by the University of
  16  *      California, Berkeley and its contributors.
  17  * 4. Neither the name of the University nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  *
  33  * $FreeBSD: src/usr.bin/passwd/local_passwd.c,v 1.24.2.3 2002/03/24 09:00:11 cjc Exp $
  34  * $DragonFly: src/usr.bin/passwd/local_passwd.c,v 1.3 2003/10/04 20:36:50 hmp Exp $
  35  *
  36  * @(#)local_passwd.c   8.3 (Berkeley) 4/2/94
  37  */
  38
  39 #include <sys/types.h>
  40 #include <sys/time.h>
  41
  42 #include <ctype.h>
  43 #include <err.h>
  44 #include <errno.h>
  45 #include <pwd.h>
  46 #include <stdio.h>
  47 #include <stdlib.h>
  48 #include <string.h>
  49 #include <time.h>
  50 #include <unistd.h>
  51
  52 #include <pw_copy.h>
  53 #include <pw_util.h>
  54 #ifdef YP
  55 #include <pw_yp.h>
  56 #endif
  57
  58 #ifdef LOGGING
  59 #include <syslog.h>
  60 #endif
  61
  62 #ifdef LOGIN_CAP
  63 #ifdef AUTH_NONE /* multiple defs :-( */
  64 #undef AUTH_NONE
  65 #endif
  66 #include <login_cap.h>
  67 #endif
  68
  69 #include "extern.h"
  70
  71 static uid_t uid;
  72 int randinit;
  73
  74 char   *tempname;
  75
  76 static unsigned char itoa64[] =         /* 0 ... 63 => ascii - 64 */
  77         "./0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";
  78
  79 void
  80 to64(char *s, long v, long n)
  81 {
  82         while (--n >= 0) {
  83                 *s++ = itoa64[v&0x3f];
  84                 v >>= 6;
  85         }
  86 }
  87
  88 char *
  89 getnewpasswd(struct passwd *pw, int nis)
  90 {
  91         int tries, min_length = 6;
  92         int force_mix_case = 1;
  93         char *p, *t;
  94 #ifdef LOGIN_CAP
  95         login_cap_t * lc;
  96 #endif
  97         char buf[_PASSWORD_LEN+1], salt[32];
  98         struct timeval tv;
  99
 100         if (!nis)
 101                 (void)printf("Changing local password for %s.\n", pw->pw_name);
 102
 103         if (uid && pw->pw_passwd[0] &&
 104             strcmp(crypt(getpass("Old password:"), pw->pw_passwd),
 105             pw->pw_passwd)) {
 106                 errno = EACCES;
 107                 pw_error(NULL, 1, 1);
 108         }
 109
 110 #ifdef LOGIN_CAP
 111         /*
 112          * Determine minimum password length, next password change date,
 113          * and whether or not to force mixed case passwords.
 114          * Note that even for NIS passwords, login_cap is still used.
 115          */
 116         if ((lc = login_getpwclass(pw)) != NULL) {
 117                 time_t  period;
 118
 119                 /* minpasswordlen capablity */
 120                 min_length = (int)login_getcapnum(lc, "minpasswordlen",
 121                                 min_length, min_length);
 122                 /* passwordtime capability */
 123                 period = login_getcaptime(lc, "passwordtime", 0, 0);
 124                 if (period > (time_t)0) {
 125                         pw->pw_change = time(NULL) + period;
 126                 }
 127                 /* mixpasswordcase capability */
 128                 force_mix_case = login_getcapbool(lc, "mixpasswordcase", 1);
 129         }
 130 #endif
 131
 132         for (buf[0] = '\0', tries = 0;;) {
 133                 p = getpass("New password:");
 134                 if (!*p) {
 135                         (void)printf("Password unchanged.\n");
 136                         pw_error(NULL, 0, 0);
 137                 }
 138                 if (strlen(p) < min_length && (uid != 0 || ++tries < 2)) {
 139                         (void)printf("Please enter a password at least %d characters in length.\n", min_length);
 140                         continue;
 141                 }
 142
 143                 if (force_mix_case) {
 144                     for (t = p; *t && islower(*t); ++t);
 145                     if (!*t && (uid != 0 || ++tries < 2)) {
 146                             (void)printf("Please don't use an all-lower case password.\nUnusual capitalization, control characters or digits are suggested.\n");
 147                             continue;
 148                     }
 149                 }
 150                 (void)strcpy(buf, p);
 151                 if (!strcmp(buf, getpass("Retype new password:")))
 152                         break;
 153                 (void)printf("Mismatch; try again, EOF to quit.\n");
 154         }
 155         /* grab a random printable character that isn't a colon */
 156         if (!randinit) {
 157                 randinit = 1;
 158                 srandomdev();
 159         }
 160 #ifdef NEWSALT
 161         salt[0] = _PASSWORD_EFMT1;
 162         to64(&salt[1], (long)(29 * 25), 4);
 163         to64(&salt[5], random(), 4);
 164         salt[9] = '\0';
 165 #else
 166         /* Make a good size salt for algoritms that can use it. */
 167         gettimeofday(&tv,0);
 168 #ifdef LOGIN_CAP
 169         if (login_setcryptfmt(lc, "md5", NULL) == NULL)
 170                 pw_error("cannot set password cipher", 1, 1);
 171         login_close(lc);
 172 #else
 173         (void)crypt_set_format("md5");
 174 #endif
 175         /* Salt suitable for anything */
 176         to64(&salt[0], random(), 3);
 177         to64(&salt[3], tv.tv_usec, 3);
 178         to64(&salt[6], tv.tv_sec, 2);
 179         to64(&salt[8], random(), 5);
 180         to64(&salt[13], random(), 5);
 181         to64(&salt[17], random(), 5);
 182         to64(&salt[22], random(), 5);
 183         salt[27] = '\0';
 184 #endif
 185         return (crypt(buf, salt));
 186 }
 187
 188 int
 189 local_passwd(char *uname)
 190 {
 191         struct passwd *pw;
 192         int pfd, tfd;
 193
 194         if (!(pw = getpwnam(uname)))
 195                 errx(1, "unknown user %s", uname);
 196
 197 #ifdef YP
 198         /* Use the right password information. */
 199         pw = (struct passwd *)&local_password;
 200 #endif
 201         uid = getuid();
 202         if (uid && uid != pw->pw_uid)
 203                 errx(1, "%s", strerror(EACCES));
 204
 205         pw_init();
 206
 207         /*
 208          * Get the new password.  Reset passwd change time to zero by
 209          * default. If the user has a valid login class (or the default
 210          * fallback exists), then the next password change date is set
 211          * by getnewpasswd() according to the "passwordtime" capability
 212          * if one has been specified.
 213          */
 214         pw->pw_change = 0;
 215         pw->pw_passwd = getnewpasswd(pw, 0);
 216
 217         pfd = pw_lock();
 218         tfd = pw_tmp();
 219         pw_copy(pfd, tfd, pw, NULL);
 220
 221         if (!pw_mkdb(uname))
 222                 pw_error((char *)NULL, 0, 1);
 223 #ifdef LOGGING
 224         syslog(LOG_DEBUG, "user %s changed their local password\n", uname);
 225 #endif
 226         return (0);
 227 }