Key split combination procedures internal to TPM

[dadiestfish2077]

The TPM Tools need the ability to perform key combination procedures internal to the hardware, thereby never exposing keying material to external memory.

For example, I have a system that has one key half inside a TPM. The other key half comes the user at runtime. I want to load the second key half into the TPM and I need the tpm to perform a key combination procedure, such as XORing and hashing, all within its internal memory. I need this combined key to stay in the TPM and be used while never being exposed to memory.

im surprised to see that something like this is not currently supported. I think it should be, as it is a common requirement to have external keying material loaded from the environment while also having the requirement that keys should never be exposed to memory.