I'am working on my client api and they have requested a public key with the following points
1-Encrypt / Decrypt algorithm is: sha256.
2 -public / private key size should be 5000 bits or more (signature algorithm sha256).
3-Padding is RSA_PKCS1_PADDING
i have tried "ssh-keygen" and send them the output
but they reply thats not a valid public key
ssh-keygen -t rsa
how can i acheive this public key with these points
thanks