pdb_smbpasswd.c

samba-3.0.22.tar.gz 编译smb服务器的源码

		}

		return pw_buf;
	}

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

/************************************************************************
 Create a new smbpasswd entry - malloced space returned.
*************************************************************************/

static char *format_new_smbpasswd_entry(const struct smb_passwd *newpwd)
{
	int new_entry_length;
	char *new_entry;
	char *p;

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

	if((new_entry = (char *)SMB_MALLOC( new_entry_length )) == NULL) {
		DEBUG(0, ("format_new_smbpasswd_entry: Malloc failed adding entry for user %s.\n",
			newpwd->smb_name ));
		return NULL;
	}

	slprintf(new_entry, new_entry_length - 1, "%s:%u:", newpwd->smb_name, (unsigned)newpwd->smb_userid);

	p = new_entry+strlen(new_entry);
	pdb_sethexpwd(p, newpwd->smb_passwd, newpwd->acct_ctrl);
	p+=strlen(p);
	*p = ':';
	p++;

	pdb_sethexpwd(p, newpwd->smb_nt_passwd, newpwd->acct_ctrl);
	p+=strlen(p);
	*p = ':';
	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, NEW_PW_FORMAT_SPACE_PADDED_LEN),
		(uint32)newpwd->pass_last_set_time);

	return new_entry;
}

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

static BOOL add_smbfilepwd_entry(struct smbpasswd_privates *smbpasswd_state, struct smb_passwd *newpwd)
{
	const char *pfile = smbpasswd_state->smbpasswd_file;
	struct smb_passwd *pwd = NULL;
	FILE *fp = NULL;
	int wr_len;
	int fd;
	size_t new_entry_length;
	char *new_entry;
	SMB_OFF_T offpos;
	uint32 max_found_uid = 0;
 
	/* Open the smbpassword file - for update. */
	fp = startsmbfilepwent(pfile, PWF_UPDATE, &smbpasswd_state->pw_file_lock_depth);

	if (fp == NULL && errno == ENOENT) {
		/* Try again - create. */
		fp = startsmbfilepwent(pfile, PWF_CREATE, &smbpasswd_state->pw_file_lock_depth);
	}

	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(smbpasswd_state, 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, &smbpasswd_state->pw_file_lock_depth);
			return False;
		}
    
		/* Look for a free uid for use in non-unix accounts */
		if (pwd->smb_userid > max_found_uid) {
			max_found_uid = pwd->smb_userid;
		}
	}

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

	if((new_entry = format_new_smbpasswd_entry(newpwd)) == 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, &smbpasswd_state->pw_file_lock_depth);
		return False;
	}

	new_entry_length = strlen(new_entry);

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

	if ((wr_len = write(fd, new_entry, new_entry_length)) != new_entry_length) {
		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(sys_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, &smbpasswd_state->pw_file_lock_depth);
		free(new_entry);
		return False;
	}

	free(new_entry);
	endsmbfilepwent(fp, &smbpasswd_state->pw_file_lock_depth);
	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
************************************************************************/

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

	char *status;
	char linebuf[256];
	char readbuf[1024];
	int c;
	fstring ascii_p16;
	fstring encode_bits;
	unsigned char *p = NULL;
	size_t linebuf_len = 0;
	FILE *fp;
	int lockfd;
	const char *pfile = smbpasswd_state->smbpasswd_file;
	BOOL found_entry = False;
	BOOL got_pass_last_set_time = False;

	SMB_OFF_T 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 = sys_fopen(pfile, "r+");

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

	lockfd = fileno(fp);

	if (!pw_file_lock(lockfd, F_WRLCK, 5, &smbpasswd_state->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.
	 */
	status = linebuf;
	while (status && !feof(fp)) {
		pwd_seekpos = sys_ftell(fp);

		linebuf[0] = '\0';

		status = fgets(linebuf, sizeof(linebuf), fp);
		if (status == NULL && ferror(fp)) {
			pw_file_unlock(lockfd, &smbpasswd_state->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]:[attributes]:LCT-XXXXXXXX:...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_m(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....
		 */

		SMB_ASSERT(sizeof(user_name) > sizeof(linebuf));

		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) {
		pw_file_unlock(lockfd, &smbpasswd_state->pw_file_lock_depth);
		fclose(fp);

		DEBUG(2, ("Cannot update entry for user %s, as they don't exist in the smbpasswd file!\n",
			pwd->smb_name));
		return False;
	}

	DEBUG(6, ("mod_smbfilepwd_entry: entry exists for user %s\n", pwd->smb_name));

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

	if (!isdigit(*p)) {
		DEBUG(0, ("mod_smbfilepwd_entry: malformed password entry for user %s (uid not number)\n",
			pwd->smb_name));
		pw_file_unlock(lockfd, &smbpasswd_state->pw_file_lock_depth);
		fclose(fp);
		return False;
	}

	while (*p && isdigit(*p)) {
		p++;
	}
	if (*p != ':') {
		DEBUG(0, ("mod_smbfilepwd_entry: malformed password entry for user %s (no : after uid)\n",
			pwd->smb_name));
		pw_file_unlock(lockfd, &smbpasswd_state->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 (linebuf_len < (PTR_DIFF(p, linebuf) + 33)) {
		DEBUG(0, ("mod_smbfilepwd_entry: malformed password entry for user %s (passwd too short)\n",
			pwd->smb_name));
		pw_file_unlock(lockfd,&smbpasswd_state->pw_file_lock_depth);
		fclose(fp);
		return (False);
	}

	if (p[32] != ':') {
		DEBUG(0, ("mod_smbfilepwd_entry: malformed password entry for user %s (no terminating :)\n",
			pwd->smb_name));
		pw_file_unlock(lockfd,&smbpasswd_state->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 for user %s (passwd too short)\n",
			pwd->smb_name));
		pw_file_unlock(lockfd,&smbpasswd_state->pw_file_lock_depth);
		fclose(fp);
		return (False);
	}

	if (p[32] != ':') {
		DEBUG(0, ("mod_smbfilepwd_entry: malformed password entry for user %s (no terminating :)\n",
			pwd->smb_name));
		pw_file_unlock(lockfd,&smbpasswd_state->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;
		encode_bits[i++] = *p++;
		while((linebuf_len > PTR_DIFF(p, linebuf)) && (*p != ']')) {
			encode_bits[i++] = *p++;
		}

		encode_bits[i++] = ']';
		encode_bits[i++] = '\0';

		if(i == NEW_PW_FORMAT_SPACE_PADDED_LEN) {
			/*
			 * We are using a new format, space padded
			 * acct ctrl field. Encode the given acct ctrl
			 * bits into it.
			 */
			fstrcpy(encode_bits, pdb_encode_acct_ctrl(pwd->acct_ctrl, NEW_PW_FORMAT_SPACE_PADDED_LEN));
		} else {
			DEBUG(0,("mod_smbfilepwd_entry:  Using old smbpasswd format for user %s. \
This is no longer supported.!\n", pwd->smb_name));
			DEBUG(0,("mod_smbfilepwd_entry:  No changes made, failing.!\n"));
			pw_file_unlock(lockfd, &smbpasswd_state->pw_file_lock_depth);
			fclose(fp);
			return False;
		}

		/* 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 LCT entry. */
			if((linebuf_len > (PTR_DIFF(p, linebuf) + 13)) && (StrnCaseCmp((char *)p, "LCT-", 4) == 0)) {
				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. */

	/* Create the 32 byte representation of the new p16 */
	pdb_sethexpwd(ascii_p16, pwd->smb_passwd, pwd->acct_ctrl);

	/* Add on the NT md4 hash */
	ascii_p16[32] = ':';
	wr_len = 66;
	pdb_sethexpwd(ascii_p16+33, pwd->smb_nt_passwd, pwd->acct_ctrl);
	ascii_p16[65] = ':';
	ascii_p16[66] = '\0'; /* null-terminate the string so that strlen works */

	/* Add on the account info bits and the time of last password change. */
	if(got_pass_last_set_time) {
		slprintf(&ascii_p16[strlen(ascii_p16)], 
			sizeof(ascii_p16)-(strlen(ascii_p16)+1),
			"%s:LCT-%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(wr_len > sizeof(linebuf)) {
		DEBUG(0, ("mod_smbfilepwd_entry: line to write (%d) is too long.\n", wr_len+1));
		pw_file_unlock(lockfd,&smbpasswd_state->pw_file_lock_depth);
		fclose(fp);
		return (False);
	}

	/*
	 * 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 (sys_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,&smbpasswd_state->pw_file_lock_depth);
		fclose(fp);
		return False;
	}

	/* Sanity check - ensure the areas we are writing are framed by ':' */
	if (read(fd, linebuf, wr_len+1) != wr_len+1) {
		DEBUG(0, ("mod_smbfilepwd_entry: read fail on file %s.\n", pfile));
		pw_file_unlock(lockfd,&smbpasswd_state->pw_file_lock_depth);
		fclose(fp);
		return False;
	}

	if ((linebuf[0] != ':') || (linebuf[wr_len] != ':'))	{
		DEBUG(0, ("mod_smbfilepwd_entry: check on passwd file %s failed.\n", pfile));
		pw_file_unlock(lockfd,&smbpasswd_state->pw_file_lock_depth);
		fclose(fp);
		return False;
	}
 
	if (sys_lseek(fd, pwd_seekpos, SEEK_SET) != pwd_seekpos) {
		DEBUG(0, ("mod_smbfilepwd_entry: seek fail on file %s.\n", pfile));
		pw_file_unlock(lockfd,&smbpasswd_state->pw_file_lock_depth);
		fclose(fp);
		return False;
	}

	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,&smbpasswd_state->pw_file_lock_depth);
		fclose(fp);
		return False;
	}

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

/************************************************************************
 Routine to delete an entry in the smbpasswd file by name.
*************************************************************************/

static BOOL del_smbfilepwd_entry(struct smbpasswd_privates *smbpasswd_state, const char *name)
{
	const char *pfile = smbpasswd_state->smbpasswd_file;
	pstring pfile2;
	struct smb_passwd *pwd = NULL;
	FILE *fp = NULL;
	FILE *fp_write = NULL;
	int pfile2_lockdepth = 0;

	slprintf(pfile2, sizeof(pfile2)-1, "%s.%u", pfile, (unsigned)sys_getpid() );

	/*
	 * Open the smbpassword file - for update. It needs to be update
	 * as we need any other processes to wait until we have replaced
	 * it.
	 */

	if((fp = startsmbfilepwent(pfile, PWF_UPDATE, &smbpasswd_state->pw_file_lock_depth)) == NULL) {