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path: root/source3/passdb/smbpass.c
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/*
 * Unix SMB/Netbios implementation. Version 1.9. SMB parameters and setup
 * Copyright (C) Andrew Tridgell 1992-1998 Modified by Jeremy Allison 1995.
 * 
 * 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.
 */

#include "includes.h"

#ifdef USE_SMBPASS_DB

extern int pw_file_lock_depth;
extern int DEBUGLEVEL;
extern pstring samlogon_user;
extern BOOL sam_logon_in_ssb;

static char s_readbuf[16 * 1024];

/***************************************************************
 Start to enumerate the smbpasswd list. Returns a void pointer
 to ensure no modification outside this module.
****************************************************************/

static void *startsmbfilepwent(BOOL update)
{
  FILE *fp = NULL;
  char *pfile = lp_smb_passwd_file();

  if (!*pfile) {
    DEBUG(0, ("startsmbfilepwent: No SMB password file set\n"));
    return (NULL);
  }
  DEBUG(10, ("startsmbfilepwent: opening file %s\n", pfile));

  fp = fopen(pfile, update ? "r+b" : "rb");

  if (fp == NULL) {
    DEBUG(0, ("startsmbfilepwent: unable to open file %s\n", pfile));
    return NULL;
  }

  /* Set a 16k buffer to do more efficient reads */
  setvbuf(fp, s_readbuf, _IOFBF, sizeof(s_readbuf));

  if (!pw_file_lock(fileno(fp), (update ? F_WRLCK : F_RDLCK), 5, &pw_file_lock_depth))
  {
    DEBUG(0, ("startsmbfilepwent: unable to lock file %s\n", pfile));
    fclose(fp);
    return NULL;
  }

  /* Make sure it is only rw by the owner */
  chmod(pfile, 0600);

  /* We have a lock on the file. */
  return (void *)fp;
}

/***************************************************************
 End enumeration of the smbpasswd list.
****************************************************************/

static void endsmbfilepwent(void *vp)
{
  FILE *fp = (FILE *)vp;

  pw_file_unlock(fileno(fp), &pw_file_lock_depth);
  fclose(fp);
  DEBUG(7, ("endsmbfilepwent: closed password file.\n"));
}

/*************************************************************************
 Routine to return the next entry in the smbpasswd list.
 this function is a nice, messy combination of reading:
 - the smbpasswd file
 - the unix password database
 - smb.conf options (not done at present).
 *************************************************************************/

static struct sam_passwd *getsmbfile21pwent(void *vp)
{
	struct smb_passwd *pw_buf = getsmbfilepwent(vp);
	static struct sam_passwd user;
	struct passwd *pwfile;

	static pstring full_name;
	static pstring home_dir;
	static pstring home_drive;
	static pstring logon_script;
	static pstring profile_path;
	static pstring acct_desc;
	static pstring workstations;
	
	if (pw_buf == NULL) return NULL;

	pwfile = getpwnam(pw_buf->smb_name);
	if (pwfile == NULL) return NULL;

	pdb_init_sam(&user);

	pstrcpy(samlogon_user, pw_buf->smb_name);

	if (samlogon_user[strlen(samlogon_user)-1] != '$')
	{
		/* XXXX hack to get standard_sub_basic() to use sam logon username */
		/* possibly a better way would be to do a become_user() call */
		sam_logon_in_ssb = True;

		user.smb_userid    = pw_buf->smb_userid;
		user.smb_grpid     = pwfile->pw_gid;

		user.user_rid  = pdb_uid_to_user_rid (user.smb_userid);
		user.group_rid = pdb_gid_to_group_rid(user.smb_grpid );

		pstrcpy(full_name    , pwfile->pw_gecos        );
		pstrcpy(logon_script , lp_logon_script       ());
		pstrcpy(profile_path , lp_logon_path         ());
		pstrcpy(home_drive   , lp_logon_drive        ());
		pstrcpy(home_dir     , lp_logon_home         ());
		pstrcpy(acct_desc    , "");
		pstrcpy(workstations , "");

		sam_logon_in_ssb = False;
	}
	else
	{
		user.smb_userid    = pw_buf->smb_userid;
		user.smb_grpid     = pwfile->pw_gid;

		user.user_rid  = pdb_uid_to_user_rid (user.smb_userid);
		user.group_rid = DOMAIN_GROUP_RID_USERS; /* lkclXXXX this is OBSERVED behaviour by NT PDCs, enforced here. */

		pstrcpy(full_name    , "");
		pstrcpy(logon_script , "");
		pstrcpy(profile_path , "");
		pstrcpy(home_drive   , "");
		pstrcpy(home_dir     , "");
		pstrcpy(acct_desc    , "");
		pstrcpy(workstations , "");
	}

	user.smb_name     = pw_buf->smb_name;
	user.full_name    = full_name;
	user.home_dir     = home_dir;
	user.dir_drive    = home_drive;
	user.logon_script = logon_script;
	user.profile_path = profile_path;
	user.acct_desc    = acct_desc;
	user.workstations = workstations;

	user.unknown_str = NULL; /* don't know, yet! */
	user.munged_dial = NULL; /* "munged" dial-back telephone number */

	user.smb_nt_passwd = pw_buf->smb_nt_passwd;
	user.smb_passwd    = pw_buf->smb_passwd;
			
	user.acct_ctrl = pw_buf->acct_ctrl;

	user.unknown_3 = 0xffffff; /* don't know */
	user.logon_divs = 168; /* hours per week */
	user.hours_len = 21; /* 21 times 8 bits = 168 */
	memset(user.hours, 0xff, user.hours_len); /* available at all hours */
	user.unknown_5 = 0x00020000; /* don't know */
	user.unknown_5 = 0x000004ec; /* don't know */

	return &user;
}

/*************************************************************************
 Routine to return the next entry in the smbpasswd list.
 *************************************************************************/

struct smb_passwd *getsmbfilepwent(void *vp)
{
  /* Static buffers we will return. */
  static struct smb_passwd pw_buf;
  static pstring  user_name;
  static unsigned char smbpwd[16];
  static unsigned char smbntpwd[16];
  FILE *fp = (FILE *)vp;
  char            linebuf[256];
  unsigned char   c;
  unsigned char  *p;
  long            uidval;
  long            linebuf_len;

  if(fp == NULL) {
    DEBUG(0,("getsmbfilepwent: Bad password file pointer.\n"));
    return NULL;
  }

  pdb_init_smb(&pw_buf);

  pw_buf.acct_ctrl = ACB_NORMAL;  

  /*
   * Scan the file, a line at a time and check if the name matches.
   */
  while (!feof(fp)) {
    linebuf[0] = '\0';

    fgets(linebuf, 256, fp);
    if (ferror(fp)) {
      return NULL;
    }

    /*
     * Check if the string is terminated with a newline - if not
     * then we must keep reading and discard until we get one.
     */
    linebuf_len = strlen(linebuf);
    if (linebuf[linebuf_len - 1] != '\n') {
      c = '\0';
      while (!ferror(fp) && !feof(fp)) {
        c = fgetc(fp);
        if (c == '\n')
          break;
      }
    } else
      linebuf[linebuf_len - 1] = '\0';

#ifdef DEBUG_PASSWORD
    DEBUG(100, ("getsmbfilepwent: got line |%s|\n", linebuf));
#endif
    if ((linebuf[0] == 0) && feof(fp)) {
      DEBUG(4, ("getsmbfilepwent: end of file reached\n"));
      break;
    }
    /*
     * The line we have should be of the form :-
     * 
     * username:uid:32hex bytes:[Account type]:LCT-12345678....other flags presently
     * ignored....
     * 
     * or,
     *
     * username:uid:32hex bytes:32hex bytes:[Account type]:LCT-12345678....ignored....
     *
     * if Windows NT compatible passwords are also present.
     * [Account type] is an ascii encoding of the type of account.
     * LCT-(8 hex digits) is the time_t value of the last change time.
     */

    if (linebuf[0] == '#' || linebuf[0] == '\0') {
      DEBUG(6, ("getsmbfilepwent: skipping comment or blank line\n"));
      continue;
    }
    p = (unsigned char *) strchr(linebuf, ':');
    if (p == NULL) {
      DEBUG(0, ("getsmbfilepwent: malformed password entry (no :)\n"));
      continue;
    }
    /*
     * As 256 is shorter than a pstring we don't need to check
     * length here - if this ever changes....
     */
    strncpy(user_name, linebuf, PTR_DIFF(p, linebuf));
    user_name[PTR_DIFF(p, linebuf)] = '\0';

    /* Get smb uid. */

    p++;		/* Go past ':' */
    if (!isdigit(*p)) {
      DEBUG(0, ("getsmbfilepwent: malformed password entry (uid not number)\n"));
      continue;
    }

    uidval = atoi((char *) p);

    while (*p && isdigit(*p))
      p++;

    if (*p != ':') {
      DEBUG(0, ("getsmbfilepwent: malformed password entry (no : after uid)\n"));
      continue;
    }

    pw_buf.smb_name = user_name;
    pw_buf.smb_userid = uidval;

    /*
     * Now get the password value - this should be 32 hex digits
     * which are the ascii representations of a 16 byte string.
     * Get two at a time and put them into the password.
     */

    /* Skip the ':' */
    p++;

    if (*p == '*' || *p == 'X') {
      /* Password deliberately invalid - end here. */
      DEBUG(10, ("getsmbfilepwent: entry invalidated for user %s\n", user_name));
      pw_buf.smb_nt_passwd = NULL;
      pw_buf.smb_passwd = NULL;
      pw_buf.acct_ctrl |= ACB_DISABLED;
      return &pw_buf;
    }

    if (linebuf_len < (PTR_DIFF(p, linebuf) + 33)) {
      DEBUG(0, ("getsmbfilepwent: malformed password entry (passwd too short)\n"));
      continue;
    }

    if (p[32] != ':') {
      DEBUG(0, ("getsmbfilepwent: malformed password entry (no terminating :)\n"));
      continue;
    }

    if (!strncasecmp((char *) p, "NO PASSWORD", 11)) {
      pw_buf.smb_passwd = NULL;
      pw_buf.acct_ctrl |= ACB_PWNOTREQ;
    } else {
      if (!pdb_gethexpwd((char *)p, (char *)smbpwd)) {
        DEBUG(0, ("getsmbfilepwent: Malformed Lanman password entry (non hex chars)\n"));
        continue;
      }
      pw_buf.smb_passwd = smbpwd;
    }

    /* 
     * Now check if the NT compatible password is
     * available.
     */
    pw_buf.smb_nt_passwd = NULL;

    p += 33; /* Move to the first character of the line after
                the lanman password. */
    if ((linebuf_len >= (PTR_DIFF(p, linebuf) + 33)) && (p[32] == ':')) {
      if (*p != '*' && *p != 'X') {
        if(pdb_gethexpwd((char *)p,(char *)smbntpwd))
          pw_buf.smb_nt_passwd = smbntpwd;
      }
      p += 33; /* Move to the first character of the line after
                  the NT password. */
    }

    DEBUG(5, ("getsmbfilepwent: returning passwd entry for user %s, uid %d\n",
			  user_name, uidval));

    if (*p == '[')
	{
      pw_buf.acct_ctrl = pdb_decode_acct_ctrl(p);

      /* Must have some account type set. */
      if(pw_buf.acct_ctrl == 0)
        pw_buf.acct_ctrl = ACB_NORMAL;

      /* Now try and get the last change time. */
      if(*p == ']')
        p++;
      if(*p == ':') {
        p++;
        if(*p && StrnCaseCmp((char *)p, "LCT-", 4)) {
          int i;
          p += 4;
          for(i = 0; i < 8; i++) {
            if(p[i] == '\0' || !isxdigit(p[i]))
              break;
          }
          if(i == 8) {
            /*
             * p points at 8 characters of hex digits - 
             * read into a time_t as the seconds since
             * 1970 that the password was last changed.
             */
            pw_buf.pass_last_set_time = (time_t)strtol((char *)p, NULL, 16);
          }
        }
      }
    } else {
      /* 'Old' style file. Fake up based on user name. */
      /*
       * Currently trust accounts are kept in the same
       * password file as 'normal accounts'. If this changes
       * we will have to fix this code. JRA.
       */
      if(pw_buf.smb_name[strlen(pw_buf.smb_name) - 1] == '$') {
        pw_buf.acct_ctrl &= ~ACB_NORMAL;
        pw_buf.acct_ctrl |= ACB_WSTRUST;
      }
    }

    return &pw_buf;
  }

  DEBUG(5,("getsmbfilepwent: end of file reached.\n"));
  return NULL;
}

/*************************************************************************
 Return the current position in the smbpasswd list as an unsigned long.
 This must be treated as an opaque token.
*************************************************************************/

static unsigned long getsmbfilepwpos(void *vp)
{
  return (unsigned long)ftell((FILE *)vp);
}

/*************************************************************************
 Set the current position in the smbpasswd list from unsigned long.
 This must be treated as an opaque token.
*************************************************************************/

static BOOL setsmbfilepwpos(void *vp, unsigned long tok)
{
  return !fseek((FILE *)vp, tok, SEEK_SET);
}

/************************************************************************
 Routine to add an entry to the smbpasswd file.
*************************************************************************/

static BOOL add_smbfile21pwd_entry(struct sam_passwd *newpwd)
{
	return False;
}

/************************************************************************
 Routine to add an entry to the smbpasswd file.
*************************************************************************/

static BOOL add_smbfilepwd_entry(struct smb_passwd *newpwd)
{
  char *pfile = lp_smb_passwd_file();
  struct smb_passwd *pwd = NULL;
  FILE *fp = NULL;

  int i;
  int wr_len;

  int fd;
  int new_entry_length;
  unsigned char *new_entry;
  long offpos;
  unsigned char *p;

  /* Open the smbpassword file - for update. */
  fp = startsmbfilepwent(True);

  if (fp == NULL) {
    DEBUG(0, ("add_smbfilepwd_entry: unable to open file.\n"));
    return False;
  }

  /*
   * Scan the file, a line at a time and check if the name matches.
   */

  while ((pwd = getsmbfilepwent(fp)) != NULL) {
    if (strequal(newpwd->smb_name, pwd->smb_name)) {
      DEBUG(0, ("add_smbfilepwd_entry: entry with name %s already exists\n", pwd->smb_name));
      endsmbfilepwent(fp);
      return False;
    }
  }

  /* Ok - entry doesn't exist. We can add it */

  /* Create a new smb passwd entry and set it to the given password. */
  /* 
   * The add user write needs to be atomic - so get the fd from 
   * the fp and do a raw write() call.
   */
  fd = fileno(fp);

  if((offpos = lseek(fd, 0, SEEK_END)) == -1) {
    DEBUG(0, ("add_smbfilepwd_entry(lseek): Failed to add entry for user %s to file %s. \
Error was %s\n", newpwd->smb_name, pfile, strerror(errno)));
    endsmbfilepwent(fp);
    return False;
  }

  new_entry_length = strlen(newpwd->smb_name) + 1 + 15 + 1 + 32 + 1 + 32 + 1 + 5 + 1 + 13 + 2;

  if((new_entry = (char *)malloc( new_entry_length )) == NULL) {
    DEBUG(0, ("add_smbfilepwd_entry(malloc): Failed to add entry for user %s to file %s. \
Error was %s\n", newpwd->smb_name, pfile, strerror(errno)));
    endsmbfilepwent(fp);
    return False;
  }

  slprintf(new_entry, new_entry_length - 1, "%s:%u:", newpwd->smb_name, (unsigned)newpwd->smb_userid);
  p = (unsigned char *)&new_entry[strlen(new_entry)];

  if(newpwd->smb_passwd != NULL) {
    for( i = 0; i < 16; i++) {
      slprintf((char *)&p[i*2], new_entry_length - (p - new_entry) - 1, "%02X", newpwd->smb_passwd[i]);
    }
  } else {
    i=0;
    if(newpwd->acct_ctrl & ACB_PWNOTREQ)
      safe_strcpy((char *)p, "NO PASSWORDXXXXXXXXXXXXXXXXXXXXX", new_entry_length - 1 - (p - new_entry));
    else
      safe_strcpy((char *)p, "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX", new_entry_length - 1 - (p - new_entry));
  }
  
  p += 32;

  *p++ = ':';

  if(newpwd->smb_nt_passwd != NULL) {
    for( i = 0; i < 16; i++) {
      slprintf((char *)&p[i*2], new_entry_length - 1 - (p - new_entry), "%02X", newpwd->smb_nt_passwd[i]);
    }
  } else {
    if(newpwd->acct_ctrl & ACB_PWNOTREQ)
      safe_strcpy((char *)p, "NO PASSWORDXXXXXXXXXXXXXXXXXXXXX", new_entry_length - 1 - (p - new_entry));
    else
      safe_strcpy((char *)p, "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX", new_entry_length - 1 - (p - new_entry));
  }

  p += 32;

  *p++ = ':';

  /* Add the account encoding and the last change time. */
  slprintf((char *)p, new_entry_length - 1 - (p - new_entry),  "%s:LCT-%08X:\n",
                                  pdb_encode_acct_ctrl(newpwd->acct_ctrl),
                     (uint32)time(NULL));

#ifdef DEBUG_PASSWORD
  DEBUG(100, ("add_smbfilepwd_entry(%d): new_entry_len %d entry_len %d made line |%s|", 
		             fd, new_entry_length, strlen(new_entry), new_entry));
#endif

  if ((wr_len = write(fd, new_entry, strlen(new_entry))) != strlen(new_entry)) {
    DEBUG(0, ("add_smbfilepwd_entry(write): %d Failed to add entry for user %s to file %s. \
Error was %s\n", wr_len, newpwd->smb_name, pfile, strerror(errno)));

    /* Remove the entry we just wrote. */
    if(ftruncate(fd, offpos) == -1) {
      DEBUG(0, ("add_smbfilepwd_entry: ERROR failed to ftruncate file %s. \
Error was %s. Password file may be corrupt ! Please examine by hand !\n", 
             newpwd->smb_name, strerror(errno)));
    }

    endsmbfilepwent(fp);
    return False;
  }

  endsmbfilepwent(fp);
  return True;
}

/************************************************************************
 Routine to search the smbpasswd file for an entry matching the username.
 and then modify its password entry. We can't use the startsmbpwent()/
 getsmbpwent()/endsmbpwent() interfaces here as we depend on looking
 in the actual file to decide how much room we have to write data.
 override = False, normal
 override = True, override XXXXXXXX'd out password or NO PASS
************************************************************************/

BOOL mod_smbfile21pwd_entry(struct sam_passwd* pwd, BOOL override)
{
	return False;
}

/************************************************************************
 Routine to search the smbpasswd file for an entry matching the username.
 and then modify its password entry. We can't use the startsmbpwent()/
 getsmbpwent()/endsmbpwent() interfaces here as we depend on looking
 in the actual file to decide how much room we have to write data.
 override = False, normal
 override = True, override XXXXXXXX'd out password or NO PASS
************************************************************************/

BOOL mod_smbfilepwd_entry(struct smb_passwd* pwd, BOOL override)
{
  /* Static buffers we will return. */
  static pstring  user_name;

  char            linebuf[256];
  char            readbuf[16 * 1024];
  unsigned char   c;
  fstring         ascii_p16;
  fstring         encode_bits;
  unsigned char  *p = NULL;
  long            linebuf_len = 0;
  FILE           *fp;
  int             lockfd;
  char           *pfile = lp_smb_passwd_file();
  BOOL found_entry = False;
  BOOL got_pass_last_set_time = False;

  long pwd_seekpos = 0;

  int i;
  int wr_len;
  int fd;

  if (!*pfile) {
    DEBUG(0, ("No SMB password file set\n"));
    return False;
  }
  DEBUG(10, ("mod_smbfilepwd_entry: opening file %s\n", pfile));

  fp = fopen(pfile, "r+");

  if (fp == NULL) {
    DEBUG(0, ("mod_smbfilepwd_entry: unable to open file %s\n", pfile));
    return False;
  }
  /* Set a 16k buffer to do more efficient reads */
  setvbuf(fp, readbuf, _IOFBF, sizeof(readbuf));

  lockfd = fileno(fp);

  if (!pw_file_lock(lockfd, F_WRLCK, 5, &pw_file_lock_depth)) {
    DEBUG(0, ("mod_smbfilepwd_entry: unable to lock file %s\n", pfile));
    fclose(fp);
    return False;
  }

  /* Make sure it is only rw by the owner */
  chmod(pfile, 0600);

  /* We have a write lock on the file. */
  /*
   * Scan the file, a line at a time and check if the name matches.
   */
  while (!feof(fp)) {
    pwd_seekpos = ftell(fp);

    linebuf[0] = '\0';

    fgets(linebuf, sizeof(linebuf), fp);
    if (ferror(fp)) {
      pw_file_unlock(lockfd, &pw_file_lock_depth);
      fclose(fp);
      return False;
    }

    /*
     * Check if the string is terminated with a newline - if not
     * then we must keep reading and discard until we get one.
     */
    linebuf_len = strlen(linebuf);
    if (linebuf[linebuf_len - 1] != '\n') {
      c = '\0';
      while (!ferror(fp) && !feof(fp)) {
        c = fgetc(fp);
        if (c == '\n') {
          break;
        }
      }
    } else {
      linebuf[linebuf_len - 1] = '\0';
    }

#ifdef DEBUG_PASSWORD
    DEBUG(100, ("mod_smbfilepwd_entry: got line |%s|\n", linebuf));
#endif

    if ((linebuf[0] == 0) && feof(fp)) {
      DEBUG(4, ("mod_smbfilepwd_entry: end of file reached\n"));
      break;
    }

    /*
     * The line we have should be of the form :-
     * 
     * username:uid:[32hex bytes]:....other flags presently
     * ignored....
     * 
     * or,
     *
     * username:uid:[32hex bytes]:[32hex bytes]:....ignored....
     *
     * if Windows NT compatible passwords are also present.
     */

    if (linebuf[0] == '#' || linebuf[0] == '\0') {
      DEBUG(6, ("mod_smbfilepwd_entry: skipping comment or blank line\n"));
      continue;
    }

    p = (unsigned char *) strchr(linebuf, ':');

    if (p == NULL) {
      DEBUG(0, ("mod_smbfilepwd_entry: malformed password entry (no :)\n"));
      continue;
    }

    /*
     * As 256 is shorter than a pstring we don't need to check
     * length here - if this ever changes....
     */
    strncpy(user_name, linebuf, PTR_DIFF(p, linebuf));
    user_name[PTR_DIFF(p, linebuf)] = '\0';
    if (strequal(user_name, pwd->smb_name)) {
      found_entry = True;
      break;
    }
  }

  if (!found_entry) return False;

  DEBUG(6, ("mod_smbfilepwd_entry: entry exists\n"));

  /* User name matches - get uid and password */
  p++;		/* Go past ':' */

  if (!isdigit(*p)) {
    DEBUG(0, ("mod_smbfilepwd_entry: malformed password entry (uid not number)\n"));
    pw_file_unlock(lockfd, &pw_file_lock_depth);
    fclose(fp);
    return False;
  }

  while (*p && isdigit(*p))
    p++;
  if (*p != ':') {
    DEBUG(0, ("mod_smbfilepwd_entry: malformed password entry (no : after uid)\n"));
    pw_file_unlock(lockfd, &pw_file_lock_depth);
    fclose(fp);
    return False;
  }

  /*
   * Now get the password value - this should be 32 hex digits
   * which are the ascii representations of a 16 byte string.
   * Get two at a time and put them into the password.
   */
  p++;

  /* Record exact password position */
  pwd_seekpos += PTR_DIFF(p, linebuf);

  if (!override && (*p == '*' || *p == 'X')) {
    /* Password deliberately invalid - end here. */
    DEBUG(10, ("mod_smbfilepwd_entry: entry invalidated for user %s\n", user_name));
    pw_file_unlock(lockfd, &pw_file_lock_depth);
    fclose(fp);
    return False;
  }

  if (linebuf_len < (PTR_DIFF(p, linebuf) + 33)) {
    DEBUG(0, ("mod_smbfilepwd_entry: malformed password entry (passwd too short)\n"));
    pw_file_unlock(lockfd,&pw_file_lock_depth);
    fclose(fp);
    return (False);
  }

  if (p[32] != ':') {
    DEBUG(0, ("mod_smbfilepwd_entry: malformed password entry (no terminating :)\n"));
    pw_file_unlock(lockfd,&pw_file_lock_depth);
    fclose(fp);
    return False;
  }

  if (!override && (*p == '*' || *p == 'X')) {
    pw_file_unlock(lockfd,&pw_file_lock_depth);
    fclose(fp);
    return False;
  }

  /* Now check if the NT compatible password is
     available. */
  p += 33; /* Move to the first character of the line after
              the lanman password. */
  if (linebuf_len < (PTR_DIFF(p, linebuf) + 33)) {
    DEBUG(0, ("mod_smbfilepwd_entry: malformed password entry (passwd too short)\n"));
    pw_file_unlock(lockfd,&pw_file_lock_depth);
    fclose(fp);
    return (False);
  }

  if (p[32] != ':') {
    DEBUG(0, ("mod_smbfilepwd_entry: malformed password entry (no terminating :)\n"));
    pw_file_unlock(lockfd,&pw_file_lock_depth);
    fclose(fp);
    return False;
  }

  /* 
   * Now check if the account info and the password last
   * change time is available.
   */
  p += 33; /* Move to the first character of the line after
              the NT password. */

  if (*p == '[') {

    i = 0;
    p++;
    while((linebuf_len > PTR_DIFF(p, linebuf)) && (*p != ']'))
      encode_bits[i++] = *p++;

    encode_bits[i] = '\0';

    /* Go past the ']' */
    if(linebuf_len > PTR_DIFF(p, linebuf))
      p++;

    if((linebuf_len > PTR_DIFF(p, linebuf)) && (*p == ':')) {
      p++;

      /* We should be pointing at the TLC entry. */
      if((linebuf_len > (PTR_DIFF(p, linebuf) + 13)) && StrnCaseCmp((char *)p, "LCT-", 4)) {

        p += 4;
        for(i = 0; i < 8; i++) {
          if(p[i] == '\0' || !isxdigit(p[i]))
            break;
        }
        if(i == 8) {
          /*
           * p points at 8 characters of hex digits -
           * read into a time_t as the seconds since
           * 1970 that the password was last changed.
           */
          got_pass_last_set_time = True;
        } /* i == 8 */
      } /* *p && StrnCaseCmp() */
    } /* p == ':' */
  } /* p == '[' */

  /* Entry is correctly formed. */

  /*
   * Do an atomic write into the file at the position defined by
   * seekpos.
   */

  /* The mod user write needs to be atomic - so get the fd from 
     the fp and do a raw write() call.
   */

  fd = fileno(fp);

  if (lseek(fd, pwd_seekpos - 1, SEEK_SET) != pwd_seekpos - 1) {
    DEBUG(0, ("mod_smbfilepwd_entry: seek fail on file %s.\n", pfile));
    pw_file_unlock(lockfd,&pw_file_lock_depth);
    fclose(fp);
    return False;
  }

  /* Sanity check - ensure the character is a ':' */
  if (read(fd, &c, 1) != 1) {
    DEBUG(0, ("mod_smbfilepwd_entry: read fail on file %s.\n", pfile));
    pw_file_unlock(lockfd,&pw_file_lock_depth);
    fclose(fp);
    return False;
  }

  if (c != ':')	{
    DEBUG(0, ("mod_smbfilepwd_entry: check on passwd file %s failed.\n", pfile));
    pw_file_unlock(lockfd,&pw_file_lock_depth);
    fclose(fp);
    return False;
  }
 
  /* Create the 32 byte representation of the new p16 */
  if(pwd->smb_passwd != NULL) {
    for (i = 0; i < 16; i++) {
      slprintf(&ascii_p16[i*2], sizeof(fstring) - 1, "%02X", (uchar) pwd->smb_passwd[i]);
    }
  } else {
    if(pwd->acct_ctrl & ACB_PWNOTREQ)
      fstrcpy(ascii_p16, "NO PASSWORDXXXXXXXXXXXXXXXXXXXXX");
    else
      fstrcpy(ascii_p16, "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX");
  }

  /* Add on the NT md4 hash */
  ascii_p16[32] = ':';
  wr_len = 65;
  if (pwd->smb_nt_passwd != NULL) {
    for (i = 0; i < 16; i++) {
      slprintf(&ascii_p16[(i*2)+33], sizeof(fstring) - 1, "%02X", (uchar) pwd->smb_nt_passwd[i]);
    }
  } else {
    if(pwd->acct_ctrl & ACB_PWNOTREQ)
      fstrcpy(&ascii_p16[33], "NO PASSWORDXXXXXXXXXXXXXXXXXXXXX");
    else
      fstrcpy(&ascii_p16[33], "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX");
  }

  /* Add on the account info bits and the time of last
     password change. */

  pwd->pass_last_set_time = time(NULL);

  if(got_pass_last_set_time) {
    slprintf(&ascii_p16[strlen(ascii_p16)], 
	     sizeof(ascii_p16)-(strlen(ascii_p16)+1),
	     ":[%s]:TLC-%08X:", 
                     encode_bits, (uint32)pwd->pass_last_set_time );
    wr_len = strlen(ascii_p16);
  }

#ifdef DEBUG_PASSWORD
  DEBUG(100,("mod_smbfilepwd_entry: "));
  dump_data(100, ascii_p16, wr_len);
#endif

  if (write(fd, ascii_p16, wr_len) != wr_len) {
    DEBUG(0, ("mod_smbfilepwd_entry: write failed in passwd file %s\n", pfile));
    pw_file_unlock(lockfd,&pw_file_lock_depth);
    fclose(fp);
    return False;
  }

  pw_file_unlock(lockfd,&pw_file_lock_depth);
  fclose(fp);
  return True;
}

static struct passdb_ops file_ops = {
  startsmbfilepwent,
  endsmbfilepwent,
  getsmbfilepwpos,
  setsmbfilepwpos,
  iterate_getsmbpwnam,          /* In passdb.c */
  iterate_getsmbpwuid,          /* In passdb.c */
  getsmbfilepwent,
  add_smbfilepwd_entry,
  mod_smbfilepwd_entry,
  getsmbfile21pwent,
  iterate_getsam21pwnam,        /* In passdb.c */
  iterate_getsam21pwuid,        /* In passdb.c */
  iterate_getsam21pwrid,        /* In passdb.c */
  add_smbfile21pwd_entry,
  mod_smbfile21pwd_entry
};

struct passdb_ops *file_initialize_password_db(void)
{    
  return &file_ops;
}

#else
static void dummy_function(void) { } /* stop some compilers complaining */
#endif /* USE_SMBPASS_DB */