loginrec.c

OpenSSL Source code for SFTP, SSH, and many others

	return ret;
}

static int
wtmp_perform_login(struct logininfo *li)
{
	struct utmp ut;

	construct_utmp(li, &ut);
	return wtmp_write(li, &ut);
}


static int
wtmp_perform_logout(struct logininfo *li)
{
	struct utmp ut;

	construct_utmp(li, &ut);
	return wtmp_write(li, &ut);
}


int
wtmp_write_entry(struct logininfo *li)
{
	switch(li->type) {
	case LTYPE_LOGIN:
		return wtmp_perform_login(li);
	case LTYPE_LOGOUT:
		return wtmp_perform_logout(li);
	default:
		log("wtmp_write_entry: invalid type field");
		return 0;
	}
}


/* Notes on fetching login data from wtmp/wtmpx
 *
 * Logouts are usually recorded with (amongst other things) a blank
 * username on a given tty line.  However, some systems (HP-UX is one)
 * leave all fields set, but change the ut_type field to DEAD_PROCESS.
 *
 * Since we're only looking for logins here, we know that the username
 * must be set correctly. On systems that leave it in, we check for
 * ut_type==USER_PROCESS (indicating a login.)
 *
 * Portability: Some systems may set something other than USER_PROCESS
 * to indicate a login process. I don't know of any as I write. Also,
 * it's possible that some systems may both leave the username in
 * place and not have ut_type.
 */

/* return true if this wtmp entry indicates a login */
static int
wtmp_islogin(struct logininfo *li, struct utmp *ut)
{
	if (strncmp(li->username, ut->ut_name,
		MIN_SIZEOF(li->username, ut->ut_name)) == 0) {
# ifdef HAVE_TYPE_IN_UTMP
		if (ut->ut_type & USER_PROCESS)
			return 1;
# else
		return 1;
# endif
	}
	return 0;
}

int
wtmp_get_entry(struct logininfo *li)
{
	struct stat st;
	struct utmp ut;
	int fd, found=0;

	/* Clear the time entries in our logininfo */
	li->tv_sec = li->tv_usec = 0;

	if ((fd = open(WTMP_FILE, O_RDONLY)) < 0) {
		log("wtmp_get_entry: problem opening %s: %s",
		    WTMP_FILE, strerror(errno));
		return 0;
	}
	if (fstat(fd, &st) != 0) {
		log("wtmp_get_entry: couldn't stat %s: %s",
		    WTMP_FILE, strerror(errno));
		close(fd);
		return 0;
	}

	/* Seek to the start of the last struct utmp */
	if (lseek(fd, -(off_t)sizeof(struct utmp), SEEK_END) == -1) {
		/* Looks like we've got a fresh wtmp file */
		close(fd);
		return 0;
	}

	while (!found) {
		if (atomicio(read, fd, &ut, sizeof(ut)) != sizeof(ut)) {
			log("wtmp_get_entry: read of %s failed: %s",
			    WTMP_FILE, strerror(errno));
			close (fd);
			return 0;
		}
		if ( wtmp_islogin(li, &ut) ) {
			found = 1;
			/* We've already checked for a time in struct
			 * utmp, in login_getlast(). */
# ifdef HAVE_TIME_IN_UTMP
			li->tv_sec = ut.ut_time;
# else
#  if HAVE_TV_IN_UTMP
			li->tv_sec = ut.ut_tv.tv_sec;
#  endif
# endif
			line_fullname(li->line, ut.ut_line,
				      MIN_SIZEOF(li->line, ut.ut_line));
# ifdef HAVE_HOST_IN_UTMP
			strlcpy(li->hostname, ut.ut_host,
				MIN_SIZEOF(li->hostname, ut.ut_host));
# endif
			continue;
		}
		/* Seek back 2 x struct utmp */
		if (lseek(fd, -(off_t)(2 * sizeof(struct utmp)), SEEK_CUR) == -1) {
			/* We've found the start of the file, so quit */
			close (fd);
			return 0;
		}
	}

	/* We found an entry. Tidy up and return */
	close(fd);
	return 1;
}
# endif /* USE_WTMP */


/**
 ** Low-level wtmpx functions
 **/

#ifdef USE_WTMPX
/* write a wtmpx entry direct to the end of the file */
/* This is a slight modification of code in OpenBSD's logwtmp.c */
static int
wtmpx_write(struct logininfo *li, struct utmpx *utx)
{
	struct stat buf;
	int fd, ret = 1;

	if ((fd = open(WTMPX_FILE, O_WRONLY|O_APPEND, 0)) < 0) {
		log("wtmpx_write: problem opening %s: %s",
		    WTMPX_FILE, strerror(errno));
		return 0;
	}

	if (fstat(fd, &buf) == 0)
		if (atomicio(write, fd, utx, sizeof(*utx)) != sizeof(*utx)) {
			ftruncate(fd, buf.st_size);
			log("wtmpx_write: problem writing %s: %s",
			    WTMPX_FILE, strerror(errno));
			ret = 0;
		}
	(void)close(fd);

	return ret;
}


static int
wtmpx_perform_login(struct logininfo *li)
{
	struct utmpx utx;

	construct_utmpx(li, &utx);
	return wtmpx_write(li, &utx);
}


static int
wtmpx_perform_logout(struct logininfo *li)
{
	struct utmpx utx;

	construct_utmpx(li, &utx);
	return wtmpx_write(li, &utx);
}


int
wtmpx_write_entry(struct logininfo *li)
{
	switch(li->type) {
	case LTYPE_LOGIN:
		return wtmpx_perform_login(li);
	case LTYPE_LOGOUT:
		return wtmpx_perform_logout(li);
	default:
		log("wtmpx_write_entry: invalid type field");
		return 0;
	}
}

/* Please see the notes above wtmp_islogin() for information about the
   next two functions */

/* Return true if this wtmpx entry indicates a login */
static int
wtmpx_islogin(struct logininfo *li, struct utmpx *utx)
{
	if ( strncmp(li->username, utx->ut_name,
		MIN_SIZEOF(li->username, utx->ut_name)) == 0 ) {
# ifdef HAVE_TYPE_IN_UTMPX
		if (utx->ut_type == USER_PROCESS)
			return 1;
# else
		return 1;
# endif
	}
	return 0;
}


int
wtmpx_get_entry(struct logininfo *li)
{
	struct stat st;
	struct utmpx utx;
	int fd, found=0;

	/* Clear the time entries */
	li->tv_sec = li->tv_usec = 0;

	if ((fd = open(WTMPX_FILE, O_RDONLY)) < 0) {
		log("wtmpx_get_entry: problem opening %s: %s",
		    WTMPX_FILE, strerror(errno));
		return 0;
	}
	if (fstat(fd, &st) != 0) {
		log("wtmpx_get_entry: couldn't stat %s: %s",
		    WTMP_FILE, strerror(errno));
		close(fd);
		return 0;
	}

	/* Seek to the start of the last struct utmpx */
	if (lseek(fd, -(off_t)sizeof(struct utmpx), SEEK_END) == -1 ) {
		/* probably a newly rotated wtmpx file */
		close(fd);
		return 0;
	}

	while (!found) {
		if (atomicio(read, fd, &utx, sizeof(utx)) != sizeof(utx)) {
			log("wtmpx_get_entry: read of %s failed: %s",
			    WTMPX_FILE, strerror(errno));
			close (fd);
			return 0;
		}
		/* Logouts are recorded as a blank username on a particular line.
		 * So, we just need to find the username in struct utmpx */
		if ( wtmpx_islogin(li, &utx) ) {
# ifdef HAVE_TV_IN_UTMPX
			li->tv_sec = utx.ut_tv.tv_sec;
# else
#  ifdef HAVE_TIME_IN_UTMPX
			li->tv_sec = utx.ut_time;
#  endif
# endif
			line_fullname(li->line, utx.ut_line, sizeof(li->line));
# ifdef HAVE_HOST_IN_UTMPX
			strlcpy(li->hostname, utx.ut_host,
				MIN_SIZEOF(li->hostname, utx.ut_host));
# endif
			continue;
		}
		if (lseek(fd, -(off_t)(2 * sizeof(struct utmpx)), SEEK_CUR) == -1) {
			close (fd);
			return 0;
		}
	}

	close(fd);
	return 1;
}
#endif /* USE_WTMPX */

/**
 ** Low-level libutil login() functions
 **/

#ifdef USE_LOGIN
static int
syslogin_perform_login(struct logininfo *li)
{
	struct utmp *ut;

	if (! (ut = (struct utmp *)malloc(sizeof(*ut)))) {
		log("syslogin_perform_login: couldn't malloc()");
		return 0;
	}
	construct_utmp(li, ut);
	login(ut);

	return 1;
}

static int
syslogin_perform_logout(struct logininfo *li)
{
# ifdef HAVE_LOGOUT
	char line[8];

	(void)line_stripname(line, li->line, sizeof(line));

	if (!logout(line)) {
		log("syslogin_perform_logout: logout() returned an error");
#  ifdef HAVE_LOGWTMP
	} else {
		logwtmp(line, "", "");
#  endif
	}
	/* FIXME: (ATL - if the need arises) What to do if we have
	 * login, but no logout?  what if logout but no logwtmp? All
	 * routines are in libutil so they should all be there,
	 * but... */
# endif
	return 1;
}

int
syslogin_write_entry(struct logininfo *li)
{
	switch (li->type) {
	case LTYPE_LOGIN:
		return syslogin_perform_login(li);
	case LTYPE_LOGOUT:
		return syslogin_perform_logout(li);
	default:
		log("syslogin_write_entry: Invalid type field");
		return 0;
	}
}
#endif /* USE_LOGIN */

/* end of file log-syslogin.c */

/**
 ** Low-level lastlog functions
 **/

#ifdef USE_LASTLOG
#define LL_FILE 1
#define LL_DIR 2
#define LL_OTHER 3

static void
lastlog_construct(struct logininfo *li, struct lastlog *last)
{
	/* clear the structure */
	memset(last, '\0', sizeof(*last));

	(void)line_stripname(last->ll_line, li->line, sizeof(last->ll_line));
	strlcpy(last->ll_host, li->hostname,
		MIN_SIZEOF(last->ll_host, li->hostname));
	last->ll_time = li->tv_sec;
}

static int
lastlog_filetype(char *filename)
{
	struct stat st;

	if (stat(LASTLOG_FILE, &st) != 0) {
		log("lastlog_perform_login: Couldn't stat %s: %s", LASTLOG_FILE,
			strerror(errno));
		return 0;
	}
	if (S_ISDIR(st.st_mode))
		return LL_DIR;
	else if (S_ISREG(st.st_mode))
		return LL_FILE;
	else
		return LL_OTHER;
}


/* open the file (using filemode) and seek to the login entry */
static int
lastlog_openseek(struct logininfo *li, int *fd, int filemode)
{
	off_t offset;
	int type;
	char lastlog_file[1024];

	type = lastlog_filetype(LASTLOG_FILE);
	switch (type) {
		case LL_FILE:
			strlcpy(lastlog_file, LASTLOG_FILE, sizeof(lastlog_file));
			break;
		case LL_DIR:
			snprintf(lastlog_file, sizeof(lastlog_file), "%s/%s",
				 LASTLOG_FILE, li->username);
			break;
		default:
			log("lastlog_openseek: %.100s is not a file or directory!",
			    LASTLOG_FILE);
			return 0;
	}

	*fd = open(lastlog_file, filemode);
	if ( *fd < 0) {
		debug("lastlog_openseek: Couldn't open %s: %s",
		    lastlog_file, strerror(errno));
		return 0;
	}

	if (type == LL_FILE) {
		/* find this uid's offset in the lastlog file */
		offset = (off_t) ((long)li->uid * sizeof(struct lastlog));

		if ( lseek(*fd, offset, SEEK_SET) != offset ) {
			log("lastlog_openseek: %s->lseek(): %s",
			 lastlog_file, strerror(errno));
			return 0;
		}
	}

	return 1;
}

static int
lastlog_perform_login(struct logininfo *li)
{
	struct lastlog last;
	int fd;

	/* create our struct lastlog */
	lastlog_construct(li, &last);

	if (!lastlog_openseek(li, &fd, O_RDWR|O_CREAT))
		return(0);

	/* write the entry */
	if (atomicio(write, fd, &last, sizeof(last)) != sizeof(last)) {
		close(fd);
		log("lastlog_write_filemode: Error writing to %s: %s",
		    LASTLOG_FILE, strerror(errno));
		return 0;
	}

	close(fd);
	return 1;
}

int
lastlog_write_entry(struct logininfo *li)
{
	switch(li->type) {
	case LTYPE_LOGIN:
		return lastlog_perform_login(li);
	default:
		log("lastlog_write_entry: Invalid type field");
		return 0;
	}
}

static void
lastlog_populate_entry(struct logininfo *li, struct lastlog *last)
{
	line_fullname(li->line, last->ll_line, sizeof(li->line));
	strlcpy(li->hostname, last->ll_host,
		MIN_SIZEOF(li->hostname, last->ll_host));
	li->tv_sec = last->ll_time;
}

int
lastlog_get_entry(struct logininfo *li)
{
	struct lastlog last;
	int fd;

	if (!lastlog_openseek(li, &fd, O_RDONLY))
		return 0;

	if (atomicio(read, fd, &last, sizeof(last)) != sizeof(last)) {
		close(fd);
		log("lastlog_get_entry: Error reading from %s: %s",
		    LASTLOG_FILE, strerror(errno));
		return 0;
	}

	close(fd);

	lastlog_populate_entry(li, &last);

	return 1;
}
#endif /* USE_LASTLOG */