This patch does the following:
1. The function names for encapsulation and decapsulation
were inconsitent in freescale's implementation and cmd_blob file.
This patch corrects the issues.
2. The function protopye is also modified to change the length parameter
from u8 to u32 to allow encapsulation and decapsulation of larger images.
3. Modified the description of km paramter in the command usage for better
readability.
Signed-off-by: Gaurav Rana <gaurav.rana@freescale.com>
Reviewed-by: Ruchika Gupta <ruchika.gupta@freescale.com>
Reviewed-by: York Sun <yorksun@freescale.com>
Freescale's SEC block has built-in Blob Protocol which provides
a method for protecting user-defined data across system power
cycles. SEC block protects data in a data structure called a Blob,
which provides both confidentiality and integrity protection.
Encapsulating data as a blob
Each time that the Blob Protocol is used to protect data, a
different randomly generated key is used to encrypt the data.
This random key is itself encrypted using a key which is derived
from SoC's non volatile secret key and a 16 bit Key identifier.
The resulting encrypted key along with encrypted data is called a blob.
The non volatile secure key is available for use only during secure boot.
During decapsulation, the reverse process is performed to get back
the original data.
Commands added
--------------
blob enc - encapsulating data as a cryptgraphic blob
blob dec - decapsulating cryptgraphic blob to get the data
Commands Syntax
---------------
blob enc src dst len km
Encapsulate and create blob of data $len bytes long
at address $src and store the result at address $dst.
$km is the 16 byte key modifier is also required for
generation/use as key for cryptographic operation. Key
modifier should be 16 byte long.
blob dec src dst len km
Decapsulate the blob of data at address $src and
store result of $len byte at addr $dst.
$km is the 16 byte key modifier is also required for
generation/use as key for cryptographic operation. Key
modifier should be 16 byte long.
Signed-off-by: Ruchika Gupta <ruchika.gupta@freescale.com>
Reviewed-by: York Sun <yorksun@freescale.com>
