auth negotiation packets
add service in getAuth
initialize sspi
ServerSPN parameter
set the IntSecurity login flag
AcquireCredentitalsHandle & FreeCredentialsHandle
InitializeSecurityContext & DeleteSecurityContext
SecBuffer and SecBufferDesc
limit the buffer to the actual returned size
empty user id is valid
localhost is the default for host
write the first sspi message in the login packet
NextBytes implementation
parse sspi token
sspi response negotiation is a token in a message
add Free, remove done from NextBytes
decode sspi token
call Complete only when it is required
extract ISC_REQ
syntax