Hi Ramakanth,

On Mon, 8 Aug 2022 at 15:20, ramakanth varala ramakanth.varala@gmail.com wrote:

Hi All,

The above issue got closed.

You can always re-open a ticket if you want to.

Need some more suggestions as mentioned below.

I believe Jerome did give a couple of suggestions in the ticket [1], have you tried any of those?

[1] https://github.com/OP-TEE/optee_os/issues/5466#issuecomment-1202408119

I am trying to get a CSR using mbedtls.

This CSR needs rsa key as one of it's parameter, as of now using the mbedTLS api (mbedtls_rsa_gen_key ) for rsa key generation.

I want rsa to be stored in TEE secure storage. This I guess can be done in two ways.

1. Use TEE_Generatekey for generating rsa key pair. Give this required key

parameter to mbeldTLS API's to get the CSR workdone . Though I can store the rsa key , but as of now I don't know how to pass TEE generated RSA key pair to mbedTLS API's.

Else

2. Use mbedTLS API's to generate rsa key and get CSR generation done.. In

this method also , don't know how mbedTLS rsa key can be stored in the TEE secure storage

Any inputs on this would be really appreciated.

Thanks

On Tue, Aug 2, 2022 at 12:41 PM ramakanth varala < ramakanth.varala@gmail.com> wrote:

...

Hi All,

I want to generate a rsa key pair with 4096 bits.

Using below mbedTLS api , inside my TEE server side implementation.

ret = mbedtls_rsa_gen_key( mbedtls_pk_rsa( key ),

mbedtls_ctr_drbg_random,

...

&ctr_drbg, 4096, 65537 );

This is resulting in the below error. mempool_alloc:197Failed to allocate 288 bytes, please tune the pool size failed

Mines is arm64 infrastructure, with kernel 4.19.183 and optee_os 3.7.0

We tried doing below change (courtesy: https://github.com/OP-TEE/optee_os/issues/3328) and recompiling tomcrypt library

In core/lib/libtomcrypt/mpi_desc.c, we changed MPI_MEMPOOL_SIZE

  #define MPI_MEMPOOL_SIZE        (42 * 1024)

to #define MPI_MEMPOOL_SIZE (82 * 1024)

This didn’t help, kindly provide your inputs.

Thanks