I want to use lsasrv!LsaProtectMemory() inside the LSASS process to encrypt a block of memory and return the ciphertext. It's part of the LsapLsasrvIfTable interface in lsasrv.dll, but unless I'm mistaken can only be accessed by another LSA extension using the lsasrv!QueryLsaInterface() function. The following text is some basic information about the internal structures.
LsapLsasrvIfTable:
dq offset LsaProtectMemory
dq offset LsaUnprotectMemory
dq offset LsaIFreeReturnBuffer