699e3efd6c
Add session based HMAC authentication plus parameter decryption and response encryption using AES. The basic design is to segregate all the nasty crypto, hash and hmac code into tpm2-sessions.c and export a usable API. The API first of all starts off by gaining a session with tpm2_start_auth_session() which initiates a session with the TPM and allocates an opaque tpm2_auth structure to handle the session parameters. The design is that session use will be single threaded from start to finish under the ops lock, so the tpm2_auth structure is stored in struct tpm2_chip to simpify the externally visible API. The session can be ended with tpm2_end_auth_session() which is designed only to be used in error legs. Ordinarily the further session API (future patches) will end or continue the session appropriately without having to call this. Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com> Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> # crypto API parts Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org> Tested-by: Jarkko Sakkinen <jarkko@kernel.org> Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>