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/*
Unix SMB/Netbios implementation.
Version 1.9.
Samba utility functions
Copyright (C) Andrew Tridgell 1992-1997
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
/* fork a child process to exec passwd and write to its
* tty to change a users password. This is running as the
* user who is attempting to change the password.
*/
/*
* This code was copied/borrowed and stolen from various sources.
* The primary source was the poppasswd.c from the authors of POPMail. This software
* was included as a client to change passwords using the 'passwd' program
* on the remote machine.
*
* This routine is called by set_user_password() in password.c only if ALLOW_PASSWORD_CHANGE
* is defined in the compiler directives located in the Makefile.
*
* This code has been hacked by Bob Nance (nance@niehs.nih.gov) and Evan Patterson
* (patters2@niehs.nih.gov) at the National Institute of Environmental Health Sciences
* and rights to modify, distribute or incorporate this change to the CAP suite or
* using it for any other reason are granted, so long as this disclaimer is left intact.
*/
/*
This code was hacked considerably for inclusion in Samba, primarily
by Andrew.Tridgell@anu.edu.au. The biggest change was the addition
of the "password chat" option, which allows the easy runtime
specification of the expected sequence of events to change a
password.
*/
#include "includes.h"
extern int DEBUGLEVEL;
#ifdef ALLOW_CHANGE_PASSWORD
#define MINPASSWDLENGTH 5
#define BUFSIZE 512
static int findpty(char **slave)
{
int master;
#if defined(SVR4) || defined(SUNOS5)
extern char *ptsname();
#else /* defined(SVR4) || defined(SUNOS5) */
static char line[12];
void *dirp;
char *dpname;
#endif /* defined(SVR4) || defined(SUNOS5) */
#if defined(SVR4) || defined(SUNOS5)
if ((master = open("/dev/ptmx", O_RDWR)) >= 1) {
grantpt(master);
unlockpt(master);
*slave = ptsname(master);
return (master);
}
#else /* defined(SVR4) || defined(SUNOS5) */
strcpy( line, "/dev/ptyXX" );
dirp = OpenDir(-1, "/dev", True);
if (!dirp) return(-1);
while ((dpname = ReadDirName(dirp)) != NULL) {
if (strncmp(dpname, "pty", 3) == 0 && strlen(dpname) == 5) {
DEBUG(3,("pty: try to open %s, line was %s\n", dpname, line ) );
line[8] = dpname[3];
line[9] = dpname[4];
if ((master = open(line, O_RDWR)) >= 0) {
DEBUG(3,("pty: opened %s\n", line ) );
line[5] = 't';
*slave = line;
CloseDir(dirp);
return (master);
}
}
}
CloseDir(dirp);
#endif /* defined(SVR4) || defined(SUNOS5) */
return (-1);
}
static int dochild(int master,char *slavedev, char *name, char *passwordprogram)
{
int slave;
struct termios stermios;
struct passwd *pass = Get_Pwnam(name,True);
int gid = pass->pw_gid;
int uid = pass->pw_uid;
#ifdef USE_SETRES
setresuid(0,0,0);
#else /* USE_SETRES */
setuid(0);
#endif /* USE_SETRES */
/* Start new session - gets rid of controlling terminal. */
if (setsid() < 0) {
DEBUG(3,("Weirdness, couldn't let go of controlling terminal\n"));
return(False);
}
/* Open slave pty and acquire as new controlling terminal. */
if ((slave = open(slavedev, O_RDWR)) < 0) {
DEBUG(3,("More weirdness, could not open %s\n",
slavedev));
return(False);
}
#if defined(SVR4) || defined(SUNOS5)
ioctl(slave, I_PUSH, "ptem");
ioctl(slave, I_PUSH, "ldterm");
#else /* defined(SVR4) || defined(SUNOS5) */
if (ioctl(slave,TIOCSCTTY,0) <0) {
DEBUG(3,("Error in ioctl call for slave pty\n"));
/* return(False); */
}
#endif /* defined(SVR4) || defined(SUNOS5) */
/* Close master. */
close(master);
/* Make slave stdin/out/err of child. */
if (dup2(slave, STDIN_FILENO) != STDIN_FILENO) {
DEBUG(3,("Could not re-direct stdin\n"));
return(False);
}
if (dup2(slave, STDOUT_FILENO) != STDOUT_FILENO) {
DEBUG(3,("Could not re-direct stdout\n"));
return(False);
}
if (dup2(slave, STDERR_FILENO) != STDERR_FILENO) {
DEBUG(3,("Could not re-direct stderr\n"));
return(False);
}
if (slave > 2) close(slave);
/* Set proper terminal attributes - no echo, canonical input processing,
no map NL to CR/NL on output. */
if (tcgetattr(0, &stermios) < 0) {
DEBUG(3,("could not read default terminal attributes on pty\n"));
return(False);
}
stermios.c_lflag &= ~(ECHO | ECHOE | ECHOK | ECHONL);
stermios.c_lflag |= ICANON;
stermios.c_oflag &= ~(ONLCR);
if (tcsetattr(0, TCSANOW, &stermios) < 0) {
DEBUG(3,("could not set attributes of pty\n"));
return(False);
}
/* make us completely into the right uid */
#ifdef USE_SETRES
setresgid(0,0,0);
setresuid(0,0,0);
setresgid(gid,gid,gid);
setresuid(uid,uid,uid);
#else
setuid(0);
seteuid(0);
setgid(gid);
setegid(gid);
setuid(uid);
seteuid(uid);
#endif
/* execl() password-change application */
if (execl("/bin/sh","sh","-c",passwordprogram,NULL) < 0) {
DEBUG(3,("Bad status returned from %s\n",passwordprogram));
return(False);
}
return(True);
}
static int expect(int master,char *expected,char *buf)
{
int n, m;
n = 0;
buf[0] = 0;
while (1) {
if (n >= BUFSIZE-1) {
return False;
}
/* allow 4 seconds for some output to appear */
m = read_with_timeout(master, buf+n, 1, BUFSIZE-1-n, 4000);
if (m < 0)
return False;
n += m;
buf[n] = 0;
{
pstring s1,s2;
pstrcpy(s1,buf);
pstrcpy(s2,expected);
if (do_match(s1, s2, False))
return(True);
}
}
}
static void pwd_sub(char *buf)
{
string_sub(buf,"\\n","\n");
string_sub(buf,"\\r","\r");
string_sub(buf,"\\s"," ");
string_sub(buf,"\\t","\t");
}
static void writestring(int fd,char *s)
{
int l;
l = strlen (s);
write (fd, s, l);
}
static int talktochild(int master, char *chatsequence)
{
char buf[BUFSIZE];
int count=0;
char *ptr=chatsequence;
fstring chatbuf;
*buf = 0;
sleep(1);
while (next_token(&ptr,chatbuf,NULL)) {
BOOL ok=True;
count++;
pwd_sub(chatbuf);
if (!strequal(chatbuf,"."))
ok = expect(master,chatbuf,buf);
#if DEBUG_PASSWORD
DEBUG(100,("chatbuf=[%s] responsebuf=[%s]\n",chatbuf,buf));
#endif
if (!ok) {
DEBUG(3,("response %d incorrect\n",count));
return(False);
}
if (!next_token(&ptr,chatbuf,NULL)) break;
pwd_sub(chatbuf);
if (!strequal(chatbuf,"."))
writestring(master,chatbuf);
#if DEBUG_PASSWORD
DEBUG(100,("sendbuf=[%s]\n",chatbuf));
#endif
}
if (count<1) return(False);
return (True);
}
BOOL chat_with_program(char *passwordprogram,char *name,char *chatsequence)
{
char *slavedev;
int master;
pid_t pid, wpid;
int wstat;
BOOL chstat;
/* allocate a pseudo-terminal device */
if ((master = findpty (&slavedev)) < 0) {
DEBUG(3,("Cannot Allocate pty for password change: %s",name));
return(False);
}
if ((pid = fork()) < 0) {
DEBUG(3,("Cannot fork() child for password change: %s",name));
return(False);
}
/* we now have a pty */
if (pid > 0){ /* This is the parent process */
if ((chstat = talktochild(master, chatsequence)) == False) {
DEBUG(3,("Child failed to change password: %s\n",name));
kill(pid, SIGKILL); /* be sure to end this process */
return(False);
}
if ((wpid = sys_waitpid(pid, &wstat, 0)) < 0) {
DEBUG(3,("The process is no longer waiting!\n\n"));
return(False);
}
if (pid != wpid) {
DEBUG(3,("We were waiting for the wrong process ID\n"));
return(False);
}
if (WIFEXITED(wstat) == 0) {
DEBUG(3,("The process exited while we were waiting\n"));
return(False);
}
if (WEXITSTATUS(wstat) != 0) {
DEBUG(3,("The status of the process exiting was %d\n", wstat));
return(False);
}
} else {
/* CHILD */
/* make sure it doesn't freeze */
alarm(20);
DEBUG(3,("Dochild for user %s (uid=%d,gid=%d)\n",name,getuid(),getgid()));
chstat = dochild(master, slavedev, name, passwordprogram);
}
DEBUG(3,("Password change %ssuccessful for user %s\n", (chstat?"":"un"), name));
return (chstat);
}
BOOL chgpasswd(char *name,char *oldpass,char *newpass)
{
pstring passwordprogram;
pstring chatsequence;
strlower(name);
DEBUG(3,("Password change for user: %s\n",name));
#if DEBUG_PASSWORD
DEBUG(100,("Passwords: old=%s new=%s\n",oldpass,newpass));
#endif
/* Take the passed information and test it for minimum criteria */
/* Minimum password length */
if (strlen(newpass) < MINPASSWDLENGTH) /* too short, must be at least MINPASSWDLENGTH */
{
DEBUG(2,("Password Change: %s, New password is shorter than MINPASSWDLENGTH\n",name));
return (False); /* inform the user */
}
/* Password is same as old password */
if (strcmp(oldpass,newpass) == 0) /* don't allow same password */
{
DEBUG(2,("Password Change: %s, New password is same as old\n",name)); /* log the attempt */
return (False); /* inform the user */
}
#if (defined(PASSWD_PROGRAM) && defined(PASSWD_CHAT))
pstrcpy(passwordprogram,PASSWD_PROGRAM);
pstrcpy(chatsequence,PASSWD_CHAT);
#else
pstrcpy(passwordprogram,lp_passwd_program());
pstrcpy(chatsequence,lp_passwd_chat());
#endif
if (!*chatsequence) {
DEBUG(2,("Null chat sequence - no password changing\n"));
return(False);
}
if (!*passwordprogram) {
DEBUG(2,("Null password program - no password changing\n"));
return(False);
}
string_sub(passwordprogram,"%u",name);
string_sub(passwordprogram,"%o",oldpass);
string_sub(passwordprogram,"%n",newpass);
string_sub(chatsequence,"%u",name);
string_sub(chatsequence,"%o",oldpass);
string_sub(chatsequence,"%n",newpass);
return(chat_with_program(passwordprogram,name,chatsequence));
}
#else
BOOL chgpasswd(char *name,char *oldpass,char *newpass)
{
DEBUG(0,("Password changing not compiled in (user=%s)\n",name));
return(False);
}
#endif
These are the contents of the former NiCE NeXT User Group NeXTSTEP/OpenStep software archive, currently hosted by Netfuture.ch.