feat: Fragment generator | NPG-0000 (#596)

Fragment generator in byte format. [As per
specification](https://github.com/input-output-hk/catalyst-core/blob/main/src/chain-libs/chain-impl-mockchain/doc/format.abnf).

The original idea was to isolate and rewrite a bare bones version of the
specification from scratch to verify the spec and our existing
implementation. This was largely done except for the cryptography. The
encrypted vote part is [manageable to
rewrite](https://github.com/input-output-hk/catalyst-core/blob/main/src/chain-libs/chain-impl-mockchain/doc/format.abnf#L170)
and somewhat **standard**.

However the ZKP proof is not, the algorithm from the treasury paper is
NOVEL and difficult to recreate with external off the shelf libs. An
isolated ZKP implementation with no baggage in the context of cat-core
requires a rewrite from scratch as there is no existing libs suitable;
any rewrite is basically a mirror of our existing cryptography and vote
crates in cat-core.

In any case, we need to use the binary of this crate within the context
of our load tester. We can potentially come back to alternatives
implementation of the ZKP stuff in the future.

Author: cong-or

Cargo.lock

@@ -58,6 +58,7 @@ members = [
   "src/vit-servicing-station-f10/vit-servicing-station-lib-f10",
   "src/vit-servicing-station-f10/vit-servicing-station-server-f10",
   "src/vit-servicing-station-f10/vit-servicing-station-tests-f10",
+  "src/sign",
 ]
 
 [workspace.dependencies]

Cargo.toml

@@ -265,6 +265,7 @@ pub(super) struct TransactionStruct {
 /// Verify the structure of the transaction and return all the offsets
 fn get_spine<P: Payload>(slice: &[u8]) -> Result<TransactionStruct, TransactionStructError> {
     let sz = slice.len();
+
     let mut codec = Codec::new(slice);
 
     // read payload

src/chain-libs/chain-impl-mockchain/src/transaction/transaction.rs

@@ -293,6 +293,17 @@ impl Zkp {
         self.ibas.iter()
     }
 
+    /// Return announcement commitments group elements
+    pub fn announcments_group_elements(&self) -> Vec<GroupElement> {
+        let mut announcements = Vec::new();
+        for g in self.ibas.clone() {
+            announcements.push(g.i);
+            announcements.push(g.b);
+            announcements.push(g.a)
+        }
+        announcements
+    }
+
     /// Return an iterator of the encryptions of the polynomial coefficients
     pub fn ds(&self) -> impl Iterator<Item = &Ciphertext> {
         self.ds.iter()
@@ -303,6 +314,18 @@ impl Zkp {
         self.zwvs.iter()
     }
 
+    /// Return an iterator of the response related to the randomness
+    pub fn response_randomness_group_elements(&self) -> Vec<Scalar> {
+        let mut response = Vec::new();
+        for z in self.zwvs.iter().clone() {
+            response.push(z.z.clone());
+            response.push(z.w.clone());
+            response.push(z.v.clone());
+        }
+
+        response
+    }
+
     /// Return R
     pub fn r(&self) -> &Scalar {
         &self.r

src/chain-libs/chain-vote/src/cryptography/zkps/unit_vector/zkp.rs

@@ -219,6 +219,7 @@ mod tests {
     #[test]
     fn unit_vector() {
         let uv = UnitVector::new(5, 0).unwrap();
+
         assert_eq!(
             &uv.iter().collect::<Vec<_>>()[..],
             [true, false, false, false, false]

src/chain-libs/chain-vote/src/encrypted_vote.rs

@@ -0,0 +1,40 @@
+[package]
+name = "sign"
+version = "0.1.0"
+edition = "2021"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+chain-crypto = { path = "../chain-libs/chain-crypto" }
+chain-vote = { path = "../chain-libs/chain-vote" }
+jormungandr-lib = { path = "../jormungandr/jormungandr-lib" }
+chain-addr = { path = "../chain-libs/chain-addr" }
+chain-core = { path = "../chain-libs/chain-core" }
+chain-impl-mockchain = { path = "../chain-libs/chain-impl-mockchain" ,features= ["audit"]}
+chain-ser = { path = "../chain-libs/chain-ser" }
+chain-storage = { path = "../chain-libs/chain-storage" }
+
+
+hex = "0.4"
+cryptoxide = "0.4.2"
+rand_chacha = "0.3"
+
+clap = { version = "4", features = ["derive", "cargo"] }
+clap_complete_command = { version = "0.5" }
+
+color-eyre = "0.6"
+thiserror = "1.0.40"
+csv = "1.1"
+
+serde = "1.0"
+serde_json = "1.0"
+serde_yaml = "0.8.17"
+rand = "0.8.3"
+bech32 = "0.8"
+
+
+rand_core = { version = "0.5.1", default-features = false }
+
+
+ed25519-dalek = "1.0.1"

src/sign/Cargo.toml

@@ -0,0 +1,34 @@
+# Fragment generator and signer:
+
+## Specifications
+ [*see here for format.abnf*](../chain-libs/chain-impl-mockchain/doc/format.abnf)
+
+ [*see here for format.md*](../chain-libs/chain-impl-mockchain/doc/format.md)
+
+## Ingredients for generating a fragment
+
+- Election public key
+- Alice public key
+- Alice private key
+- proposal to vote on
+- vote plan id (hash of voteplan)
+
+*Example usage:*
+
+```
+cargo build --release -p sign
+```  
+
+*Generate raw fragment in byte representation*
+
+```bash
+
+ELECTION_PUB_KEY=ristretto255_votepk1ppxnuxrqa4728evnp2ues000uvwvwtxmtf77ejc29lknjuqqu44s4cfmja
+ALICE_SK=56e367979579e2ce27fbd305892b0706b7dede999a534a864a7430a5c6aefd3c
+ALICE_PK=ea084d2d80ed0ab681333d934efc56df3868d13d46a2de3b7f27f40b62e5344d
+PROPOSAL=5
+VOTE_PLAN_ID=36ad42885189a0ac3438cdb57bc8ac7f6542e05a59d1f2e4d1d38194c9d4ac7b
+
+./target/release/sign --election-pub-key $ELECTION_PUB_KEY --private-key $ALICE_SK --public-key $ALICE_PK --proposal $PROPOSAL --vote-plan-id $VOTE_PLAN_ID
+
+```