Ubuntu 13.04 was unable to see the adapter

Put the following into a file called usbreset.c:

/* usbreset -- send a USB port reset to a USB device */

#include <stdio.h>
#include <unistd.h>
#include <fcntl.h>
#include <errno.h>
#include <sys/ioctl.h>

#include <linux/usbdevice_fs.h>


int main(int argc, char **argv)
{
    const char *filename;
    int fd;
    int rc;

    if (argc != 2) {
        fprintf(stderr, "Usage: usbreset device-filenamen");
        return 1;
    }
    filename = argv[1];

    fd = open(filename, O_WRONLY);
    if (fd < 0) {
        perror("Error opening output file");
        return 1;
    }

    printf("Resetting USB device %sn", filename);
    rc = ioctl(fd, USBDEVFS_RESET, 0);
    if (rc < 0) {
        perror("Error in ioctl");
        return 1;
    }
    printf("Reset successfuln");

    close(fd);
    return 0;
}

The run the following commands in terminal:

1. Compile the program:

   $ cc usbreset.c -o usbreset
   

2. Get the Bus and Device ID of the USB device you want to reset:

   $ lsusb
   Bus 002 Device 003: ID 0fe9:9010 DVICO
   

3. Make our compiled program executable:

   $ chmod +x usbreset
   

4. Execute the program with sudo privilege; make necessary substitution for <Bus> and <Device> ids as found by running the lsusb command:

   $ sudo ./usbreset /dev/bus/usb/002/003
   

By: Li Lo

apt-get install cryptsetup

Using dm-crypt/LUKS/cryptsetup by doing the following steps:

1. Create a sparse disk image file: dd if=/dev/zero of=IMAGEFILE bs=1 count=1 seek=SIZE
2. Generate a random key in a file: dd if=/dev/random of=KEYFILE bs=1024 count=1
3. Use cryptsetup luksFormat –key-file KEYFILE –cipher aes-xts-plain –size 512 IMAGEFILE (Or use another cipher and key length. Note that 512 here will give you AES with 256 bits because of XTS.) Example 2: cryptsetup luksFormat –key-file KEYFILE –cipher aes-xts-plain64:sha512 -s 512 IMAGEFILE
4. Open crypt container: cryptsetup luksOpen –key-file KEYFILE IMAGEFILE NAME
5. Create file system on /dev/mapper/NAME.
6. Mount file system as usual.

Your script would just have to do steps 4 and 6. For unmounting/closing, umount the file system and call cryptsetup luksClose NAME.

Note that using sparse files will leak the information which sectors of the disk have been used already (the same way as not overwriting a partition with random data before encrypting it). It is up to you to decide whether this is ok for you.

Also note that deleting files will not make the disk image smaller. The sparse file will grow monotonically.

By: P Wendler