Hi Volodymyr

Thanks so much for the quick reply!

I have a follow up question: how to skip the additional op-tee header when I analyze the .ta? 
I've tried to use the objdump or readelf, but both of them complain that the .ta file is not an ELF.
Should I manually somehow remove the additional header, or, are there any tools to check the .ta just like using objdump or readelf?

Thanks in advance!

Brs,
Yin

2018-06-14 13:18 GMT-04:00 Volodymyr Babchuk <volodymyr_babchuk@epam.com>:
Hi Yin

On 14.06.18 19:26, Yin Liu wrote:
Hello,

I'm learning the Trusted application that can be run in the TEE.

I was wondering whether there are some ways to check the .ta file's instructions, just like using objdump or readelf on ELF.
Yes. .ta is a regular ELF file with additional OP-TEE header at the beginning. You can skip this header and work with it as with any other regular ELF.

I'm also interested how does the .ta be protected? What's the difference between the .ta and normal executable?
TA should be signed. OP-TEE checks signature prior to TA invocation.
Actually, mentioned header holds this signature.

You can take a look at sign.py script from OP-TEE distribution.

--
Volodymyr Babchuk