1. Default environment will be used for secure boot flow
which can't be edited or saved.
2. Command for secure boot is predefined in the default
environment which will run on autoboot (and autoboot is
the only option allowed in case of secure boot) and it
looks like this:
#define CONFIG_SECBOOT \
"setenv bs_hdraddr 0xe8e00000;" \
"esbc_validate $bs_hdraddr;" \
"source $img_addr;" \
"esbc_halt;"
#endif
3. Boot Script can contain esbc_validate commands and bootm command.
Uboot source command used in default secure boot command will
run the bootscript.
4. Command esbc_halt added to ensure either bootm executes
after validation of images or core should just spin.
Signed-off-by: Ruchika Gupta <ruchika.gupta@freescale.com>
Signed-off-by: Gaurav Rana <gaurav.rana@freescale.com>
Reviewed-by: York Sun <yorksun@freescale.com>
1. esbc_validate command is meant for validating header and
signature of images (Boot Script and ESBC uboot client).
SHA-256 and RSA operations are performed using SEC block in HW.
This command works on both PBL based and Non PBL based Freescale
platforms.
Command usage:
esbc_validate img_hdr_addr [pub_key_hash]
2. ESBC uboot client can be linux. Additionally, rootfs and device
tree blob can also be signed.
3. In the event of header or signature failure in validation,
ITS and ITF bits determine further course of action.
4. In case of soft failure, appropriate error is dumped on console.
5. In case of hard failure, SoC is issued RESET REQUEST after
dumping error on the console.
6. KEY REVOCATION Feature:
QorIQ platforms like B4/T4 have support of srk key table and key
revocation in ISBC code in Silicon.
The srk key table allows the user to have a key table with multiple
keys and revoke any key in case of particular key gets compromised.
In case the ISBC code uses the key revocation and srk key table to
verify the u-boot code, the subsequent chain of trust should also
use the same.
6. ISBC KEY EXTENSION Feature:
This feature allows large number of keys to be used for esbc validation
of images. A set of public keys is being signed and validated by ISBC
which can be further used for esbc validation of images.
Signed-off-by: Ruchika Gupta <ruchika.gupta@freescale.com>
Signed-off-by: Gaurav Rana <gaurav.rana@freescale.com>
Reviewed-by: York Sun <yorksun@freescale.com>
