proxy is a trampoline that can be used on other blockchains

[bennetyee]

kmaas/contracts/Account.sol

Line 100 in a4b924c

function makeProxyTx(

the makeProxyTx and proxy functionality are pretty distinct: makeProxyTx uses the "EOA" private key managed by this KMaaS contract instance, and proxy does not, with the exception of nonce manipulation.

the nonce management has issues mentioned elsewhere (#5).

we should split this into two contracts. the makeProxyTx capable one would be running on a confidential smart contract blockchain such as sapphire, and the proxy implementing contract would be running on any ethereum-compatible blockchain. now, the makeProxyTx one has to do nonce management by itself, and the proxy one only trampolines the call to the real one, but with msg.sender being the "EOA" key being managed by the KMaaS contract. now we have a new capability: the sapphire chain can do complex authorization policies for contracts that did not have notions for such built in, e.g., m-out-of-n signer threshold authorization, at least one signature from each of m (typically disjoint) key sets, etc.