The cert_create tool calculates the hash of each BL image and includes
it as an ASN.1 OCTET STRING in the corresponding certificate extension.
Without additional information, the firmware running on the platform
has to know in advance the algorithm used to generate the hash.
This patch modifies the cert_create tool so the certificate extensions
that include an image hash are generated according to the following
ASN.1 structure:
DigestInfo ::= SEQUENCE {
digestAlgorithm AlgorithmIdentifier,
digest OCTET STRING
}
AlgorithmIdentifier ::= SEQUENCE {
algorithm OBJECT IDENTIFIER,
parameters ANY DEFINED BY algorithm OPTIONAL
}
The PolarSSL module has been updated to extract the image hash
from the certificate extension according to this structure.
Change-Id: I6d83430f12a8a0eea8447bec7c936e903f644c85
Update the top level makefile to allow platform ports to exist in
subdirectories at any level instead of one level under `plat/`. The
makefile recursively searches for all files called `platform.mk` in
all subdirectories of `plat/`. The directory containing
`platform.mk` is the platform name. Platform names must be unique
across the codebase.
Replace usage of HELP_PLATFORMS in the Makefile with PLATFORMS since
these are both used to report the same information back to the user.
Update the TSP and cert_create tool makefiles in a similar way
to support a deeper platform port directory structure.
Also add PLAT_<plat_name> as a define passed through the top level
makefile to the source files, to allow build time variation in common
platform code.
Change-Id: I213420164808c5ddb99a26144e8e3f141a7417b7
This patch replaces SHA1 by SHA256 in the 'cert_create' tool, so
certificate signatures are generated according to the NSA Suite B
cryptographic algorithm requirements.
Documentation updated accordingly.
Change-Id: I7be79e6b2b62dac8dc78a4f4f5006e37686bccf6
This patch adds a tool that generates all the necessary elements
to establish the chain of trust (CoT) between the images.
The tool reads the binary images and signing keys and outputs the
corresponding certificates that will be used by the target at run
time to verify the authenticity of the images.
Note: the platform port must provide the file platform_oid.h. This
file will define the OIDs of the x509 extensions that will be added
to the certificates in order to establish the CoT.
Change-Id: I2734d6808b964a2107ab3a4805110698066a04be
Juan Castillo
Dan Handley