topic How to identify HAB signed image with CSF header? in i.MX Processors

How to identify HAB signed image with CSF header?

kanimozhi_t — Wed, 17 Feb 2021 12:38:28 GMT

Hi,

I would like to differentiate between plain FIT image and HAB signed image on i.MX 8M based processors. So it would be useful if you could answer the following.

1. Can you share the CSF header structure for i.MX 8M FIT image?

2. Do i.MX 6UL & i.MX 8M has same CSF header structure since both are HABv4?

Thanks in advance.

Re: How to identify HAB signed image with CSF header?

IvanRuiz — Wed, 17 Feb 2021 20:26:48 GMT

Hello,

A typical CSF header is as follows, it does not depend on the i.MX processor but rather on HABv4. So, the following is a generic example of a CSF header for HABv4, please see below:

[Header]
   Version = 4.1
   Hash Algorithm = sha256
   Engine Configuration = 0
   Certificate Format = X509
   Signature Format = CMS

Hope it helps!

BR,

Ivan.

Re: How to identify HAB signed image with CSF header?

kanimozhi_t — Fri, 26 Feb 2021 05:38:30 GMT

Thanks for the reply, this is the header in text format! But we want to check the CSF header in binary format.

By analysing the u-boot code we found that CSF would start with 0xD4 in binary format. Like this we would want to get the entire CSF binary structure so that it can be verified in the provided binary file.

Thanks in advance.