Abstract: A secure portable storage device includes a control module. When a host sends a first key to the control module with a write command so as to command the control module to write the first key into a redirecting file, the control module stores the first key in a temporary working buffer and verifies whether the first key is valid; when the first key is valid, the control module sends a second key and an encrypted content data to the host for generating a third key by decrypting the second key according to the first key and decrypting the encrypted content data into a content data according to the third key. Moreover, when the host sends multiple read commands to the control module in sequence, the control module verifies whether a sequence of the read commands received is valid and sends the second key and the encrypted content data to the host for an encryption. Related apparatuses, methods and techniques also are provided.

Abstract: The invention provides an access control for a secure portable storage device. The control method is applied to a host for accessing from the secure portable storage device. The control method includes the following steps. First, the host transmits a first key into a first temporary space in the file system of the secure portable storage device. Next, the secure portable storage device verifies if the first key is valid. If the first key is valid, an encrypted content key is duplicated into a second temporary space. Then, the encrypted content key is uploaded to the host. Afterward, the encrypted content key is decrypted into a content key. Lastly, an encrypted content data stored in the secure portable storage device is decrypted into a content data by use of the content key.