# stronghold.rs - feat/refactoring

###### tags: `Stronghold` `P2P`

Deadline 30 October

1. Rewrite of stronghold crate (high level)
- facilitate future code ownership
- wrap cryptographic operations in `crate::runtime::zone`
- message interface (rewrite client)
- evict wallet specific logic (e.g. password clear timeout)
- use a key derivation function to push the "human readable password UTF-8 string" out of the interfaces
- Security Levels marker
- Rate limiter
- noise for remote vs local ?
- ed25519 -> https://github.com/ZcashFoundation/ed25519-zebra

2. top level actor for engine

## Message Requirements:

Using a macro for the DSL

Think about backwards compatibility of the messages!

### Commands: (Procedures)
- Digest/KDF
- Sign verify (including multiple signers/verifiers)
- Derive pubkey
- Generate private key
- Encrypt decrypt (note that here we might want to restrict/configure what data are allowed to exist outside of the vault)
* this also functions as a database's write and read
- Purge (with optional ttl (0 means request immediate garbage colllect)
- RNG (does this put unnecessary exposure on the cryptographic source in use?)
- HD key derivation (slip10 bip32 whatever)

### Payloads: (Intents?)
- key material
- serializable data
- signatures

### Expected Response:
- status code
- transformation

### Auxiliary commands: (Procedures)
- relay message to other stronghold via peer ID
- current time?
- capability negotiation:
* security level
* topology
* available algorithms
* software version
* system metadata
* peers (with their pubkeys (verifiable identity))
* whois

# Input/output port style

enum Input {
   Const(Vec<u8>),
   Record(RecordId),
}

enum Output {
   Return,
   Record(RecordId),
   OhShit(Error)
}

enum Digest_aka_KDF {
   Noop, // check lengths
   SHA1,
}

struct Sign {
    key: Input,
    digest: Digest,
    out: Output,
}

struct DerivePubkey {
}

struct Encrypt {
}

struct Decrypt 

### Abstract Syntax Tree (AST)

"Using the wallet snapshot file, this $password to decrypt it, and my seed $record stored inside of it, please return the ed25519 $signature for this $transaction and the transaction $checksum"

------
snapshot: ‘~/.engine/wallet.stronghold’
password: ‘***************************’
record_id: { 'a': ‘0d0140252ad234923’, 'b': '0ab012' },
payload: ‘A letter to Bob from Alice that I want signed.’
action: [‘sign::ed25519(a, digest::sha1(payload))’, ‘checksum(b)’]
return: [‘signature’, ‘checksum’]
------