/*
 * backup-fs.c
 * I)ruid <druid@caughq.org>
 *
 * This backup utility will push it's tar.gz through a keyauth'd
 * SSH tunnel to a remote filesystem, avoiding having to store the
 * backup locally. Will use the system fstab for backup targets or
 * a user supplied fstab file.
 *
 */

#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <time.h>
#include <unistd.h>

/* Define your backup user and your backup host here */
#define BACKUP_USER "backup"
#define BACKUP_HOST "druid.druid.net"
#define SSH_PORT 22

/* my personal debuggin output */
#define DEBUG 1


main(int argc, char *argv[] ) {
	FILE *f1;
	int x, y;
	char *fstab;
	char mountpoint[256];
	char fstype[32];
	char datestring[32];
	char buffer[256], final[256];
	char hostname[128];
	char tar_command[256];
	char disk[32];
	char modified_disk[32];

	/* If an fstab file is not specified, default to /etc/fstab */
	if( !argv[1] )
		fstab = "/etc/fstab";
	else
		fstab = argv[1];

	/* Get Current Hostname */
	gethostname( hostname, sizeof(hostname) );
	if( DEBUG == 1 ) printf( "Hostname:	[%s]\n", hostname );

	/* Get Formatted Date String */
	sprintf( datestring, "%s", getdatestr() );

	/* Backup the fstab outside of the archive for reference */
	sprintf( tar_command, "/bin/cat %s | ssh -p %d -l %s %s \"cat - > incoming/%s-fstab-%s\"", fstab, SSH_PORT, BACKUP_USER, BACKUP_HOST, hostname, datestring );
	system( tar_command );

	/* Parse fstab for entries */
	f1 = fopen( fstab, "r" );
	if( f1 == NULL ) {
		printf( "Error opening %s\n", fstab );
		exit( -1 );
	}
	if( DEBUG == 1 ) printf( "%s opened for reading...\n", fstab );

	while( fgets( buffer, sizeof(buffer), f1 ) ) {
		buffer[strlen(buffer)-1] = '\0';
		if( DEBUG == 1 ) printf( "Read [%s]\n", buffer );
		y = 0;
		for( x = 0; x <= strlen(buffer); x++ ) {
			if( buffer[x] == '\t' || buffer[x] == ' ' ) {
				final[y] = ':';
				y++;
				x++;
				while( buffer[x] == '\t' || buffer[x] == ' ' )
					x++;
			}	
			final[y] = buffer[x];
			y++;
		}
		if( DEBUG == 1 ) printf( "Mod: [%s]\n", final);

		sprintf( disk, "%s", strtok( final, ":" ) );
		sprintf( mountpoint, "%s", strtok ( NULL, ":" ) );
		sprintf( fstype, "%s", strtok( NULL, ":" ) );

		if( DEBUG == 1 ) printf( "Disk:	[%s]\n", disk );
		if( DEBUG == 1 ) printf( "Mountpoint:	[%s]\n", mountpoint );
		if( DEBUG == 1 ) printf( "FSType:	[%s]\n", fstype );

		for( x = 0; x <= strlen(disk); x++ ) {
			if( disk[x] == '/' ) {
				if( x == 0 )
					modified_disk[x] = '-';
				else
					modified_disk[x] = '.';
			} else
				modified_disk[x] = disk[x];
		}
		if( DEBUG == 1 ) printf( "ModDisk:	[%s]\n", modified_disk );

		/* If the entry is of type ext2, we will back it up */
		if( strcmp( fstype, "ext2" ) == 0 ) { 
			/* Build tar command string */
			sprintf( tar_command, "/bin/tar -czl %s | ssh -p %d -l %s %s \"cat - > incoming/%s%s-%s.tar.gz\"", mountpoint, SSH_PORT, BACKUP_USER, BACKUP_HOST, hostname, modified_disk, datestring );
			if( DEBUG == 1 ) printf( "Command:	[%s]\n", tar_command );

			system( tar_command );
		}

	}	 

	exit( 1 );
}


/* Return the DateString for the archive name */
getdatestr() {
	time_t t;
	int year;
	char holdme[4096];
	char outfile[1024];
	char month[1024];
	char day[1024];
	char id[1024];

	/* Get the year from the current time */
	t = time(NULL);
	sprintf( holdme, "%s", ctime( &t ) );
	if( DEBUG == 1 ) printf( "Time: [%s]\n", holdme );

	sprintf( id, "%s", strtok( holdme, " " ) );
	sprintf( month, "%s", strtok( NULL, " " ) );
	sprintf( day, "%s", strtok( NULL, " " ) ); 
	sprintf( id, "%s", strtok( NULL, ":" ) );
	sprintf( id, "%s", strtok( NULL, " " ) );
	sprintf( id, "%s", strtok( NULL, "\n" ) );
	year = atoi( id );
	/* End of year (y2k) Bug Fix - If the log is for Dec 31, then it will be
		 the next year when the process above finds the year (if executed at/near
		 midnight), therefore we go back a year */
	if( !strcmp( month, "Dec" ) && !strcmp( day, "31" ) )
		year--;
	/* Convert the Month to a number value (so things list incrementally in
		 filesystem list */
	if( strcmp( month, "Jan" ) == 0 )
		sprintf( month, "01" );
	if( strcmp( month, "Feb" ) == 0 )
		sprintf( month, "02" );
	if( strcmp( month, "Mar" ) == 0 )
		sprintf( month, "03" );
	if( strcmp( month, "Apr" ) == 0 )
		sprintf( month, "04" );
	if( strcmp( month, "May" ) == 0 )
		sprintf( month, "05" );
	if( strcmp( month, "Jun" ) == 0 )
		sprintf( month, "06" );
	if( strcmp( month, "Jul" ) == 0 )
		sprintf( month, "07" );
	if( strcmp( month, "Aug" ) == 0 )
		sprintf( month, "08" );
	if( strcmp( month, "Sep" ) == 0 )
		sprintf( month, "09" );
	if( strcmp( month, "Oct" ) == 0 )
		sprintf( month, "10" );
	if( strcmp( month, "Nov" ) == 0 )
		sprintf( month, "11" );
	if( strcmp( month, "Dec" ) == 0 )
		sprintf( month, "12" );

	/* Pad the day with 0's so it's at least 2 char's */
	if( strlen( day ) < 2 ) {
		sprintf( id, "0%s", day );
		sprintf( day, "%s", id );
	}

	/* Archive the logs */
	sprintf( outfile, "%d.%s.%s", year, month, day );
	if( DEBUG == 1 ) printf( "DateString:	[%s]\n", outfile );
	return( outfile );
}