2 Unix SMB/CIFS implementation.
3 Samba utility functions
4 Copyright (C) Andrew Tridgell 1992-1998
5 Copyright (C) Andrew Bartlett 2001-2002
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2 of the License, or
10 (at your option) any later version.
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with this program; if not, write to the Free Software
19 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
22 /* fork a child process to exec passwd and write to its
23 * tty to change a users password. This is running as the
24 * user who is attempting to change the password.
28 * This code was copied/borrowed and stolen from various sources.
29 * The primary source was the poppasswd.c from the authors of POPMail. This software
30 * was included as a client to change passwords using the 'passwd' program
31 * on the remote machine.
33 * This routine is called by set_user_password() in password.c only if ALLOW_PASSWORD_CHANGE
34 * is defined in the compiler directives located in the Makefile.
36 * This code has been hacked by Bob Nance (nance@niehs.nih.gov) and Evan Patterson
37 * (patters2@niehs.nih.gov) at the National Institute of Environmental Health Sciences
38 * and rights to modify, distribute or incorporate this change to the CAP suite or
39 * using it for any other reason are granted, so long as this disclaimer is left intact.
43 This code was hacked considerably for inclusion in Samba, primarily
44 by Andrew.Tridgell@anu.edu.au. The biggest change was the addition
45 of the "password chat" option, which allows the easy runtime
46 specification of the expected sequence of events to change a
52 extern struct passdb_ops pdb_ops;
54 static NTSTATUS check_oem_password(const char *user,
55 uchar * lmdata, const uchar * lmhash,
56 const uchar * ntdata, const uchar * nthash,
57 SAM_ACCOUNT **hnd, char *new_passwd,
60 #if ALLOW_CHANGE_PASSWORD
62 static int findpty(char **slave)
69 #if defined(HAVE_GRANTPT)
70 /* Try to open /dev/ptmx. If that fails, fall through to old method. */
71 if ((master = sys_open("/dev/ptmx", O_RDWR, 0)) >= 0)
75 *slave = (char *)ptsname(master);
79 ("findpty: Unable to create master/slave pty pair.\n"));
80 /* Stop fd leak on error. */
87 ("findpty: Allocated slave pty %s\n", *slave));
91 #endif /* HAVE_GRANTPT */
93 fstrcpy(line, "/dev/ptyXX");
95 dirp = opendir("/dev");
98 while ((dpname = readdirname(dirp)) != NULL)
100 if (strncmp(dpname, "pty", 3) == 0 && strlen(dpname) == 5)
103 ("pty: try to open %s, line was %s\n", dpname,
107 if ((master = sys_open(line, O_RDWR, 0)) >= 0)
109 DEBUG(3, ("pty: opened %s\n", line));
121 static int dochild(int master, const char *slavedev, const struct passwd *pass,
122 const char *passwordprogram, BOOL as_root)
125 struct termios stermios;
132 ("dochild: user doesn't exist in the UNIX password database.\n"));
139 gain_root_privilege();
141 /* Start new session - gets rid of controlling terminal. */
145 ("Weirdness, couldn't let go of controlling terminal\n"));
149 /* Open slave pty and acquire as new controlling terminal. */
150 if ((slave = sys_open(slavedev, O_RDWR, 0)) < 0)
152 DEBUG(3, ("More weirdness, could not open %s\n", slavedev));
156 ioctl(slave, I_PUSH, "ptem");
157 ioctl(slave, I_PUSH, "ldterm");
158 #elif defined(TIOCSCTTY)
159 if (ioctl(slave, TIOCSCTTY, 0) < 0)
161 DEBUG(3, ("Error in ioctl call for slave pty\n"));
169 /* Make slave stdin/out/err of child. */
171 if (sys_dup2(slave, STDIN_FILENO) != STDIN_FILENO)
173 DEBUG(3, ("Could not re-direct stdin\n"));
176 if (sys_dup2(slave, STDOUT_FILENO) != STDOUT_FILENO)
178 DEBUG(3, ("Could not re-direct stdout\n"));
181 if (sys_dup2(slave, STDERR_FILENO) != STDERR_FILENO)
183 DEBUG(3, ("Could not re-direct stderr\n"));
189 /* Set proper terminal attributes - no echo, canonical input processing,
190 no map NL to CR/NL on output. */
192 if (tcgetattr(0, &stermios) < 0)
195 ("could not read default terminal attributes on pty\n"));
198 stermios.c_lflag &= ~(ECHO | ECHOE | ECHOK | ECHONL);
199 stermios.c_lflag |= ICANON;
201 stermios.c_oflag &= ~(ONLCR);
203 if (tcsetattr(0, TCSANOW, &stermios) < 0)
205 DEBUG(3, ("could not set attributes of pty\n"));
209 /* make us completely into the right uid */
212 become_user_permanently(uid, gid);
216 ("Invoking '%s' as password change program.\n",
219 /* execl() password-change application */
220 if (execl("/bin/sh", "sh", "-c", passwordprogram, NULL) < 0)
222 DEBUG(3, ("Bad status returned from %s\n", passwordprogram));
228 static int expect(int master, char *issue, char *expected)
231 int attempts, timeout, nread, len;
234 for (attempts = 0; attempts < 2; attempts++) {
235 if (!strequal(issue, ".")) {
236 if (lp_passwd_chat_debug())
237 DEBUG(100, ("expect: sending [%s]\n", issue));
239 if ((len = write(master, issue, strlen(issue))) != strlen(issue)) {
240 DEBUG(2,("expect: (short) write returned %d\n", len ));
245 if (strequal(expected, "."))
252 while ((len = read_socket_with_timeout(master, buffer + nread, 1,
253 sizeof(buffer) - nread - 1,
259 /* Eat leading/trailing whitespace before match. */
261 pstrcpy( str, buffer);
262 trim_string( str, " ", " ");
264 if ((match = (unix_wild_match(expected, str) == 0)))
269 if (lp_passwd_chat_debug())
270 DEBUG(100, ("expect: expected [%s] received [%s] match %s\n",
271 expected, buffer, match ? "yes" : "no" ));
277 DEBUG(2, ("expect: %s\n", strerror(errno)));
282 DEBUG(10,("expect: returning %s\n", match ? "True" : "False" ));
286 static void pwd_sub(char *buf)
288 all_string_sub(buf, "\\n", "\n", 0);
289 all_string_sub(buf, "\\r", "\r", 0);
290 all_string_sub(buf, "\\s", " ", 0);
291 all_string_sub(buf, "\\t", "\t", 0);
294 static int talktochild(int master, const char *seq)
297 fstring issue, expected;
301 while (next_token(&seq, expected, NULL, sizeof(expected)))
306 if (!expect(master, issue, expected))
308 DEBUG(3, ("Response %d incorrect\n", count));
312 if (!next_token(&seq, issue, NULL, sizeof(issue)))
317 if (!strequal(issue, ".")) {
318 /* we have one final issue to send */
319 fstrcpy(expected, ".");
320 if (!expect(master, issue, expected))
327 static BOOL chat_with_program(char *passwordprogram, struct passwd *pass,
328 char *chatsequence, BOOL as_root)
339 ("chat_with_program: user doesn't exist in the UNIX password database.\n"));
343 /* allocate a pseudo-terminal device */
344 if ((master = findpty(&slavedev)) < 0)
347 ("Cannot Allocate pty for password change: %s\n",
353 * We need to temporarily stop CatchChild from eating
354 * SIGCLD signals as it also eats the exit status code. JRA.
357 CatchChildLeaveStatus();
359 if ((pid = sys_fork()) < 0)
362 ("Cannot fork() child for password change: %s\n",
369 /* we now have a pty */
371 { /* This is the parent process */
372 if ((chstat = talktochild(master, chatsequence)) == False)
375 ("Child failed to change password: %s\n",
377 kill(pid, SIGKILL); /* be sure to end this process */
380 while ((wpid = sys_waitpid(pid, &wstat, 0)) < 0)
392 DEBUG(3, ("The process is no longer waiting!\n\n"));
399 * Go back to ignoring children.
408 ("We were waiting for the wrong process ID\n"));
411 if (WIFEXITED(wstat) == 0)
414 ("The process exited while we were waiting\n"));
417 if (WEXITSTATUS(wstat) != 0)
420 ("The status of the process exiting was %d\n",
431 * Lose any oplock capabilities.
433 oplock_set_capability(False, False);
435 /* make sure it doesn't freeze */
442 ("Dochild for user %s (uid=%d,gid=%d)\n", pass->pw_name,
443 (int)getuid(), (int)getgid()));
445 dochild(master, slavedev, pass, passwordprogram,
452 * The child should never return from dochild() ....
456 ("chat_with_program: Error: dochild() returned %d\n",
463 ("Password change %ssuccessful for user %s\n",
464 (chstat ? "" : "un"), pass->pw_name));
469 BOOL chgpasswd(const char *name, const char *oldpass, const char *newpass, BOOL as_root)
471 pstring passwordprogram;
472 pstring chatsequence;
479 DEBUG(1, ("NULL username specfied to chgpasswd()!\n"));
482 pass = Get_Pwnam(name);
484 DEBUG(1, ("Username does not exist in system passwd!\n"));
492 DEBUG(3, ("Password change for user: %s\n", name));
495 DEBUG(100, ("Passwords: old=%s new=%s\n", oldpass, newpass));
498 /* Take the passed information and test it for minimum criteria */
499 /* Minimum password length */
500 if (strlen(newpass) < lp_min_passwd_length()) {
501 /* too short, must be at least MINPASSWDLENGTH */
502 DEBUG(0, ("Password Change: user %s, New password is shorter than minimum password length = %d\n",
503 name, lp_min_passwd_length()));
504 return (False); /* inform the user */
507 /* Password is same as old password */
508 if (strcmp(oldpass, newpass) == 0) {
509 /* don't allow same password */
510 DEBUG(2, ("Password Change: %s, New password is same as old\n", name)); /* log the attempt */
511 return (False); /* inform the user */
515 * Check the old and new passwords don't contain any control
519 len = strlen(oldpass);
520 for (i = 0; i < len; i++) {
521 if (iscntrl((int)oldpass[i])) {
523 ("chat_with_program: oldpass contains control characters (disallowed).\n"));
528 len = strlen(newpass);
529 for (i = 0; i < len; i++) {
530 if (iscntrl((int)newpass[i])) {
532 ("chat_with_program: newpass contains control characters (disallowed).\n"));
538 if (lp_pam_password_change()) {
545 ret = smb_pam_passchange(pass->pw_name, oldpass, newpass);
547 ret = smb_pam_passchange(name, oldpass, newpass);
557 /* A non-PAM password change just doen't make sense without a valid local user */
562 ("chgpasswd: user %s doesn't exist in the UNIX password database.\n",
567 pstrcpy(passwordprogram, lp_passwd_program());
568 pstrcpy(chatsequence, lp_passwd_chat());
570 if (!*chatsequence) {
571 DEBUG(2, ("chgpasswd: Null chat sequence - no password changing\n"));
575 if (!*passwordprogram) {
576 DEBUG(2, ("chgpasswd: Null password program - no password changing\n"));
581 /* The password program *must* contain the user name to work. Fail if not. */
582 if (strstr(passwordprogram, "%u") == NULL) {
583 DEBUG(0,("chgpasswd: Running as root the 'passwd program' parameter *MUST* contain \
584 the string %%u, and the given string %s does not.\n", passwordprogram ));
589 pstring_sub(passwordprogram, "%u", name);
590 /* note that we do NOT substitute the %o and %n in the password program
591 as this would open up a security hole where the user could use
592 a new password containing shell escape characters */
594 pstring_sub(chatsequence, "%u", name);
595 all_string_sub(chatsequence, "%o", oldpass, sizeof(pstring));
596 all_string_sub(chatsequence, "%n", newpass, sizeof(pstring));
597 return (chat_with_program
598 (passwordprogram, pass, chatsequence, as_root));
601 #else /* ALLOW_CHANGE_PASSWORD */
603 BOOL chgpasswd(const char *name, const char *oldpass, const char *newpass, BOOL as_root)
605 DEBUG(0, ("Password changing not compiled in (user=%s)\n", name));
608 #endif /* ALLOW_CHANGE_PASSWORD */
610 /***********************************************************
611 Code to check the lanman hashed password.
612 ************************************************************/
614 BOOL check_lanman_password(char *user, uchar * pass1,
615 uchar * pass2, SAM_ACCOUNT **hnd)
617 uchar unenc_new_pw[16];
618 uchar unenc_old_pw[16];
619 SAM_ACCOUNT *sampass = NULL;
621 const uint8 *lanman_pw;
625 ret = pdb_getsampwnam(sampass, user);
629 DEBUG(0,("check_lanman_password: getsampwnam returned NULL\n"));
630 pdb_free_sam(&sampass);
634 acct_ctrl = pdb_get_acct_ctrl (sampass);
635 lanman_pw = pdb_get_lanman_passwd (sampass);
637 if (acct_ctrl & ACB_DISABLED) {
638 DEBUG(0,("check_lanman_password: account %s disabled.\n", user));
639 pdb_free_sam(&sampass);
643 if (lanman_pw == NULL) {
644 if (acct_ctrl & ACB_PWNOTREQ) {
645 /* this saves the pointer for the caller */
649 DEBUG(0, ("check_lanman_password: no lanman password !\n"));
650 pdb_free_sam(&sampass);
655 /* Get the new lanman hash. */
656 D_P16(lanman_pw, pass2, unenc_new_pw);
658 /* Use this to get the old lanman hash. */
659 D_P16(unenc_new_pw, pass1, unenc_old_pw);
661 /* Check that the two old passwords match. */
662 if (memcmp(lanman_pw, unenc_old_pw, 16)) {
663 DEBUG(0,("check_lanman_password: old password doesn't match.\n"));
664 pdb_free_sam(&sampass);
668 /* this saves the pointer for the caller */
673 /***********************************************************
674 Code to change the lanman hashed password.
675 It nulls out the NT hashed password as it will
677 ************************************************************/
679 BOOL change_lanman_password(SAM_ACCOUNT *sampass, uchar *pass2)
681 static uchar null_pw[16];
682 uchar unenc_new_pw[16];
687 if (sampass == NULL) {
688 DEBUG(0,("change_lanman_password: no smb password entry.\n"));
692 acct_ctrl = pdb_get_acct_ctrl(sampass);
693 pwd = pdb_get_lanman_passwd(sampass);
695 if (acct_ctrl & ACB_DISABLED) {
696 DEBUG(0,("change_lanman_password: account %s disabled.\n",
697 pdb_get_username(sampass)));
702 if (acct_ctrl & ACB_PWNOTREQ) {
704 memset(no_pw, '\0', 14);
705 E_P16(no_pw, null_pw);
707 /* Get the new lanman hash. */
708 D_P16(null_pw, pass2, unenc_new_pw);
710 DEBUG(0,("change_lanman_password: no lanman password !\n"));
714 /* Get the new lanman hash. */
715 D_P16(pwd, pass2, unenc_new_pw);
718 if (!pdb_set_lanman_passwd(sampass, unenc_new_pw, PDB_CHANGED)) {
722 if (!pdb_set_nt_passwd (sampass, NULL, PDB_CHANGED)) {
723 return False; /* We lose the NT hash. Sorry. */
726 if (!pdb_set_pass_changed_now (sampass)) {
727 pdb_free_sam(&sampass);
728 /* Not quite sure what this one qualifies as, but this will do */
732 /* Now flush the sam_passwd struct to persistent storage */
734 ret = pdb_update_sam_account (sampass);
740 /***********************************************************
741 Code to check and change the OEM hashed password.
742 ************************************************************/
743 NTSTATUS pass_oem_change(char *user,
744 uchar * lmdata, uchar * lmhash,
745 uchar * ntdata, uchar * nthash)
748 const char *unix_user;
749 SAM_ACCOUNT *sampass = NULL;
751 = check_oem_password(user, lmdata, lmhash, ntdata, nthash,
752 &sampass, new_passwd, sizeof(new_passwd));
754 if (!NT_STATUS_IS_OK(nt_status))
758 * At this point we have the new case-sensitive plaintext
759 * password in the fstring new_passwd. If we wanted to synchronise
760 * with UNIX passwords we would call a UNIX password changing
761 * function here. However it would have to be done as root
762 * as the plaintext of the old users password is not
766 unix_user = pdb_get_username(sampass);
768 nt_status = change_oem_password(sampass, NULL, new_passwd);
770 memset(new_passwd, 0, sizeof(new_passwd));
772 pdb_free_sam(&sampass);
777 /***********************************************************
778 Code to check the OEM hashed password.
780 this function ignores the 516 byte nt OEM hashed password
781 but does use the lm OEM password to check the nt hashed-hash.
783 ************************************************************/
785 static NTSTATUS check_oem_password(const char *user,
786 uchar * lmdata, const uchar * lmhash,
787 const uchar * ntdata, const uchar * nthash,
788 SAM_ACCOUNT **hnd, char *new_passwd,
791 static uchar null_pw[16];
792 static uchar null_ntpw[16];
793 SAM_ACCOUNT *sampass = NULL;
794 const uint8 *lanman_pw, *nt_pw;
798 uchar unenc_old_ntpw[16];
800 uchar unenc_old_pw[16];
804 BOOL nt_pass_set = (ntdata != NULL && nthash != NULL);
808 pdb_init_sam(&sampass);
811 ret = pdb_getsampwnam(sampass, user);
815 DEBUG(0, ("check_oem_password: getsmbpwnam returned NULL\n"));
816 pdb_free_sam(&sampass);
817 return NT_STATUS_WRONG_PASSWORD;
819 TODO: check what Win2k returns for this:
820 return NT_STATUS_NO_SUCH_USER;
824 acct_ctrl = pdb_get_acct_ctrl(sampass);
826 if (acct_ctrl & ACB_DISABLED) {
827 DEBUG(0,("check_lanman_password: account %s disabled.\n", user));
828 pdb_free_sam(&sampass);
829 return NT_STATUS_ACCOUNT_DISABLED;
832 /* construct a null password (in case one is needed */
835 nt_lm_owf_gen(no_pw, null_ntpw, null_pw);
837 /* save pointers to passwords so we don't have to keep looking them up */
838 lanman_pw = pdb_get_lanman_passwd(sampass);
839 nt_pw = pdb_get_nt_passwd(sampass);
841 /* check for null passwords */
842 if (lanman_pw == NULL) {
843 if (!(acct_ctrl & ACB_PWNOTREQ)) {
844 DEBUG(0,("check_oem_password: no lanman password !\n"));
845 pdb_free_sam(&sampass);
846 return NT_STATUS_WRONG_PASSWORD;
850 if (pdb_get_nt_passwd(sampass) == NULL && nt_pass_set) {
851 if (!(acct_ctrl & ACB_PWNOTREQ)) {
852 DEBUG(0,("check_oem_password: no ntlm password !\n"));
853 pdb_free_sam(&sampass);
854 return NT_STATUS_WRONG_PASSWORD;
859 * Call the hash function to get the new password.
861 SamOEMhash( lmdata, lanman_pw, 516);
864 * The length of the new password is in the last 4 bytes of
868 new_pw_len = IVAL(lmdata, 512);
870 if (new_pw_len < 0 || new_pw_len > new_passwd_size - 1) {
871 DEBUG(0,("check_oem_password: incorrect password length (%d).\n", new_pw_len));
872 pdb_free_sam(&sampass);
873 return NT_STATUS_WRONG_PASSWORD;
878 * nt passwords are in unicode
880 pull_ucs2(NULL, new_passwd,
881 (const smb_ucs2_t *)&lmdata[512 - new_pw_len],
882 new_passwd_size, new_pw_len, 0);
884 memcpy(new_passwd, &lmdata[512 - new_pw_len], new_pw_len);
885 new_passwd[new_pw_len] = 0;
889 * To ensure we got the correct new password, hash it and
890 * use it as a key to test the passed old password.
893 nt_lm_owf_gen(new_passwd, new_ntp16, new_p16);
897 * Now use new_p16 as the key to see if the old
900 D_P16(new_p16, lmhash, unenc_old_pw);
902 if (memcmp(lanman_pw, unenc_old_pw, 16)) {
903 DEBUG(0,("check_oem_password: old lm password doesn't match.\n"));
904 pdb_free_sam(&sampass);
905 return NT_STATUS_WRONG_PASSWORD;
908 #ifdef DEBUG_PASSWORD
910 ("check_oem_password: password %s ok\n", new_passwd));
917 * Now use new_p16 as the key to see if the old
920 D_P16(new_ntp16, lmhash, unenc_old_pw);
921 D_P16(new_ntp16, nthash, unenc_old_ntpw);
923 if (memcmp(lanman_pw, unenc_old_pw, 16)) {
924 DEBUG(0,("check_oem_password: old lm password doesn't match.\n"));
925 pdb_free_sam(&sampass);
926 return NT_STATUS_WRONG_PASSWORD;
929 if (memcmp(nt_pw, unenc_old_ntpw, 16)) {
930 DEBUG(0,("check_oem_password: old nt password doesn't match.\n"));
931 pdb_free_sam(&sampass);
932 return NT_STATUS_WRONG_PASSWORD;
934 #ifdef DEBUG_PASSWORD
935 DEBUG(100, ("check_oem_password: password %s ok\n", new_passwd));
942 /***********************************************************
943 Code to change the oem password. Changes both the lanman
944 and NT hashes. Old_passwd is almost always NULL.
945 ************************************************************/
947 NTSTATUS change_oem_password(SAM_ACCOUNT *hnd, char *old_passwd, char *new_passwd)
952 if (time(NULL) < pdb_get_pass_can_change_time(hnd)) {
953 DEBUG(1, ("user %s cannot change password now, must wait until %s\n",
954 pdb_get_username(hnd), http_timestring(pdb_get_pass_can_change_time(hnd))));
955 return NT_STATUS_PASSWORD_RESTRICTION;
958 if (account_policy_get(AP_MIN_PASSWORD_LEN, &min_len) && (strlen(new_passwd) < min_len)) {
959 DEBUG(1, ("user %s cannot change password - password too short\n",
960 pdb_get_username(hnd)));
961 DEBUGADD(1, (" account policy min password len = %d\n", min_len));
962 return NT_STATUS_PASSWORD_RESTRICTION;
963 /* return NT_STATUS_PWD_TOO_SHORT; */
966 /* Take the passed information and test it for minimum criteria */
967 /* Minimum password length */
968 if (strlen(new_passwd) < lp_min_passwd_length()) {
969 /* too short, must be at least MINPASSWDLENGTH */
970 DEBUG(1, ("Password Change: user %s, New password is shorter than minimum password length = %d\n",
971 pdb_get_username(hnd), lp_min_passwd_length()));
972 return NT_STATUS_PASSWORD_RESTRICTION;
973 /* return NT_STATUS_PWD_TOO_SHORT; */
976 /* TODO: Add cracklib support here */
979 * If unix password sync was requested, attempt to change
980 * the /etc/passwd database first. Return failure if this cannot
983 * This occurs before the oem change, because we don't want to
984 * update it if chgpasswd failed.
986 * Conditional on lp_unix_password_sync() because we don't want
987 * to touch the unix db unless we have admin permission.
990 if(lp_unix_password_sync() &&
991 !chgpasswd(pdb_get_username(hnd), old_passwd, new_passwd, False)) {
992 return NT_STATUS_ACCESS_DENIED;
995 if (!pdb_set_plaintext_passwd (hnd, new_passwd)) {
996 return NT_STATUS_ACCESS_DENIED;
999 /* Now write it into the file. */
1001 ret = pdb_update_sam_account (hnd);
1005 return NT_STATUS_ACCESS_DENIED;
1008 return NT_STATUS_OK;