private tx example (native)

[brenzi]

Write an example for private transactions.

• based on ERC20
• coded in native Rust-inside-enclave (not in WASM-inside-enclave)
• state must carry a hashmap with all account balances

Example Story

1. (shielding) Alice sends substrate-native currency (SRML balances) to the substraTEE-worker account (an account for all substraTEE enclaves with a shared private key).
2. The substraTEE-worker enclave creates a shielded account for Alice inside encrypted state
3. Bob creates a keypair and tells Alice the pubkey
4. Alice sends a shielded transfer request to substraTEE proxy (Alice to Bob: 10 tokens)
5. substraTEE-worker enclave processes the request and transfers tokens from Alice to Bob. receipt is written onchain
6. (optional) Alice verifies block inclusion of the receipt and sends Bob the receipt along with the shielded tx
7. Bob queries his account balance directly with the substraTEE-worker with a signed RPC or WS call (over TLS)

Suggestion:

• refactor for modular STF. separate Business logic into its own module (definition of state, definition of STF)

[brenzi]

Consider instantiating an entire Balances module inside the enclave to provide token functionality. the outdated branch https://github.com/scs/substraTEE-worker/tree/brenzi-contract-modular shows how this could be done

[brenzi]

Re-visiting the ink contract PoC:

• https://github.com/scs/substraTEE-worker/tree/brenzi-contract-modular
• https://github.com/brenzi/substrate/tree/brenzi-contract-replace-sr-io

We should proceed as follows:

1. re-visit substrate patches in brenzi-contract-replace-sr-io and apply them to https://github.com/scs/substraTEE-node/tree/master/sr-tee-io. New feature sgx
2. check mods for worker and integrate balances module

[brenzi]

first part done: sr-io with sgx feature
https://github.com/scs/substraTEE-node/tree/brenzi-private-tx/sr-tee-io

[brenzi]

second part started: instantiate runtime with balancesbut without contracts within enclave
https://github.com/scs/substraTEE-worker/tree/brenzi-private-tx

[brenzi]

simple demo works:

*** Getting the amount of the registered workers
[<] Found 1  workers

[>] Getting the first worker's from the substraTEE-node
[<] Got first worker's coordinates:
    W1's public key : "5Gkzji8EtE1hTjVzTmZXWqrs6sqcHcbCooGqVH7iRRuxdnar"
    W1's url: "127.0.0.1:2000"

[>] Get the shielding key from W1 (=5Gkzji8EtE1hTjVzTmZXWqrs6sqcHcbCooGqVH7iRRuxdnar)
[<] Got worker shielding key Rsa3072KeyPair: { n:CF67550FB00AB959A76219EA35188B360380037123FCAA77B683A791A1F980331F9D9E11D04C7F5FB3B63787F8AAB579FDFFE1DCE79A29B6ACED2628635C8463965D5D839BD58072AA77B8CAE124E40562955FE9936DAE2976CD57B41A2DE89EEDBF9DA77C155365E8BB45DCA1E0EC3B32604D9489712762BE63B3D1F04801D796887F70115BFDD440450A04BFE81DEE7BE718F56F766E6B0C2D9DE270583C4DFBA64FD59B4DE39C07977F1FD2956588DDBF73987EECB5BB303AF2115C4E72879C5EC69B7CD5C00DAEF9F9B062B40ADA16984C574246C8AB882A79D2E1C2F597C1017FBA69D7449BAD85ADE822D92A775DB1766F21C886E762C3E260390B72C82515F1D48FD190059B419C639E3688BCC2070E9CDB6BDDD49202B7296EA2AB01EA2D3AC2990C5078446582A4C03194BBF8D7E557B4503FF4645C053D7288398C79781F642F3A8D399195E6D2E6F74B434791D881BC97BAA0F0B228BD031C40E357BC61644E68CC40F3E08BDCBBD92E306FA9353FAEA05FDCBFCF4729FECC008C, e:01000001 }

[+] Alice's Incognito Pubkey: 5Dt1Wg85pXGLstt36t6TDdvXXoCtG6zkUL17KkyVaPYSrzGH

[+] Bob's Incognito Pubkey: 5GTTq4EnvMk4oTXYJp2kqTd2T9hbnARuee5awLiKFKsxWgRy

[+] pre-funding Alice's Incognito account (ROOT call)
[+] Subscribed, waiting for event...

[+] Received confirm call from 5Gkzji8EtE1hTjVzTmZXWqrs6sqcHcbCooGqVH7iRRuxdnar
[+] query Alice's Incognito account balance
    got getter response from worker: Ok("State is 1000000")
[+] query Bob's Incognito account balance
    got getter response from worker: Ok("State is 0")

*** incognito transfer from Alice to Bob

[+] Subscribed, waiting for event...

[+] Received confirm call from 5Gkzji8EtE1hTjVzTmZXWqrs6sqcHcbCooGqVH7iRRuxdnar
[+] query Alice's Incognito account balance
    got getter response from worker: Ok("State is 900000")
[+] query Bob's Incognito account balance
    got getter response from worker: Ok("State is 100000")