Versal Authentication Support - 2024.2 English

Meta Header Authentication

For a Versal adaptive SoC, Bootgen authenticates the meta header based on the parameters under the bif attribute "metaheader." A snippet of the usage is shown below.

metaheader
{
	authentication = rsa,
	pskfile = psk.pem,
	sskfile = ssk.pem
}

Authentication Optimization

Starting in v2024.1, For a Versal adaptive SoC, you can opt for authentication time reduction.

If you are using the same SPK (with the same authentication algorithm and key strength) for the Meta Header and partitions loaded by the PLM, it is possible to avoid the SPK and partition data signature validations. You can enable the use of authenticated partition digests that are stored in the optional Image Header Table. The partition digests are SHA digests that are used to validate the integrity of the partition data at boot.

When reading the Meta Header, PLM authenticates and copies the table of partition digests to be used during partition loading. Authentication can be skipped for any partition with a digest entry in the table. In this case, the partition data is passed through the SHA engine, and the resulting digest is compared against the authenticated digest value stored for that partition in the Image Header Table.

PPK Hash for eFUSE

Bootgen generates the PPK hash for storing in eFUSE for PPK to be trusted. This step is required only for authentication with eFUSE mode, and can be skipped for AHWRoT. The value from efuseppksha.txt can be programmed to eFUSE for authentication with the eFUSE for AHWRoT.

BIF File Example

The following is a sample BIF file, generate_hash_ppk.bif.

generate_hash_ppk:
{
    pskfile = primary0.pem
    sskfile = secondary0.pem
    image
    {
        name = pmc_ss, id = 0x1c000001
        { type=bootloader, authentication=rsa, file=plm.elf}
        { type=pmcdata, load=0xf2000000, file=pmc_cdo.bin}
    }
}

Command

The command to generate PPK hash for eFUSE programming is:

bootgen –image generate_hash_ppk.bif –arch versal –w –o test.bin –efuseppkbits efuseppksha.txt

Cumulative Secure Boot Operations for Versal Adaptive SoC