Supply a RecommendedTranscript type of DT<Blake2b512>

coins/monero/Cargo.toml

@@ -23,7 +23,7 @@ curve25519-dalek = { version = "3", features = ["std"] }
 group = { version = "0.12", optional = true }
 
 dalek-ff-group = { path = "../../crypto/dalek-ff-group", optional = true }
-transcript = { package = "transcript-trait", path = "../../crypto/transcript", optional = true }
+transcript = { package = "transcript-trait", path = "../../crypto/transcript", features = ["recommended"], optional = true }
 frost = { package = "modular-frost", path = "../../crypto/frost", features = ["ed25519"], optional = true }
 
 monero = "0.16"

coins/monero/src/frost.rs

@@ -9,15 +9,13 @@ use curve25519_dalek::{
   edwards::EdwardsPoint as DPoint
 };
 
-use transcript::{Transcript as TranscriptTrait, DigestTranscript};
-use frost::Curve;
+use transcript::{Transcript, RecommendedTranscript};
+use frost::curves::Curve;
 pub use frost::curves::dalek::Ed25519;
 use dalek_ff_group as dfg;
 
 use crate::random_scalar;
 
-pub type Transcript = DigestTranscript::<blake2::Blake2b512>;
-
 #[derive(Clone, Error, Debug)]
 pub enum MultisigError {
   #[error("internal error ({0})")]
@@ -43,7 +41,7 @@ impl DLEqProof {
     // the proper order if they want to reach consensus
     // It'd be a poor API to have CLSAG define a new transcript solely to pass here, just to try to
     // merge later in some form, when it should instead just merge xH (as it does)
-    let mut transcript = Transcript::new(b"DLEq Proof");
+    let mut transcript = RecommendedTranscript::new(b"DLEq Proof");
     // Bit redundant, keeps things consistent
     transcript.domain_separate(b"DLEq");
     // Doesn't include G which is constant, does include H which isn't, even though H manipulation

coins/monero/src/ringct/clsag/multisig.rs

@@ -13,18 +13,18 @@ use curve25519_dalek::{
 
 use group::Group;
 
-use transcript::Transcript as TranscriptTrait;
+use transcript::{Transcript, RecommendedTranscript};
 use frost::{FrostError, MultisigView, algorithm::Algorithm};
 use dalek_ff_group as dfg;
 
 use crate::{
   hash_to_point,
-  frost::{Transcript, MultisigError, Ed25519, DLEqProof, read_dleq},
+  frost::{MultisigError, Ed25519, DLEqProof, read_dleq},
   ringct::clsag::{ClsagInput, Clsag}
 };
 
 impl ClsagInput {
-  fn transcript<T: TranscriptTrait>(&self, transcript: &mut T) {
+  fn transcript<T: Transcript>(&self, transcript: &mut T) {
     // Doesn't domain separate as this is considered part of the larger CLSAG proof
 
     // Ring index
@@ -72,7 +72,7 @@ struct Interim {
 #[allow(non_snake_case)]
 #[derive(Clone, Debug)]
 pub struct ClsagMultisig {
-  transcript: Transcript,
+  transcript: RecommendedTranscript,
 
   H: EdwardsPoint,
   // Merged here as CLSAG needs it, passing it would be a mess, yet having it beforehand requires a round
@@ -87,7 +87,7 @@ pub struct ClsagMultisig {
 
 impl ClsagMultisig {
   pub fn new(
-    transcript: Transcript,
+    transcript: RecommendedTranscript,
     details: Arc<RwLock<Option<ClsagDetails>>>
   ) -> Result<ClsagMultisig, MultisigError> {
     Ok(
@@ -120,7 +120,7 @@ impl ClsagMultisig {
 }
 
 impl Algorithm<Ed25519> for ClsagMultisig {
-  type Transcript = Transcript;
+  type Transcript = RecommendedTranscript;
   type Signature = (Clsag, EdwardsPoint);
 
   fn preprocess_addendum<R: RngCore + CryptoRng>(

coins/monero/src/tests/clsag.rs

@@ -5,6 +5,9 @@ use rand::{RngCore, rngs::OsRng};
 
 use curve25519_dalek::{constants::ED25519_BASEPOINT_TABLE, scalar::Scalar};
 
+#[cfg(feature = "multisig")]
+use transcript::RecommendedTranscript;
+
 use crate::{
   Commitment,
   random_scalar, generate_key_image,
@@ -12,7 +15,7 @@ use crate::{
   ringct::clsag::{ClsagInput, Clsag}
 };
 #[cfg(feature = "multisig")]
-use crate::{frost::{Ed25519, MultisigError, Transcript}, ringct::clsag::{ClsagDetails, ClsagMultisig}};
+use crate::{frost::{Ed25519, MultisigError}, ringct::clsag::{ClsagDetails, ClsagMultisig}};
 
 #[cfg(feature = "multisig")]
 use frost::tests::{key_gen, algorithm_machines, sign};
@@ -96,7 +99,7 @@ fn clsag_multisig() -> Result<(), MultisigError> {
     algorithm_machines(
       &mut OsRng,
       ClsagMultisig::new(
-        Transcript::new(b"Monero Serai CLSAG Test"),
+        RecommendedTranscript::new(b"Monero Serai CLSAG Test"),
         Arc::new(RwLock::new(Some(
           ClsagDetails::new(
             ClsagInput::new(

coins/monero/src/wallet/send/multisig.rs

@@ -5,7 +5,7 @@ use rand_chacha::ChaCha12Rng;
 
 use curve25519_dalek::{traits::Identity, scalar::Scalar, edwards::{EdwardsPoint, CompressedEdwardsY}};
 
-use transcript::Transcript as TranscriptTrait;
+use transcript::{Transcript, RecommendedTranscript};
 use frost::{
   FrostError, MultisigKeys,
   sign::{
@@ -15,7 +15,7 @@ use frost::{
 };
 
 use crate::{
-  frost::{Transcript, Ed25519},
+  frost::Ed25519,
   random_scalar, ringct::{clsag::{ClsagInput, ClsagDetails, ClsagMultisig}, bulletproofs::Bulletproofs, RctPrunable},
   transaction::{Input, Transaction},
   rpc::Rpc,
@@ -26,7 +26,7 @@ pub struct TransactionMachine {
   signable: SignableTransaction,
   i: u16,
   included: Vec<u16>,
-  transcript: Transcript,
+  transcript: RecommendedTranscript,
 
   decoys: Vec<Decoys>,
 
@@ -38,7 +38,7 @@ pub struct TransactionSignMachine {
   signable: SignableTransaction,
   i: u16,
   included: Vec<u16>,
-  transcript: Transcript,
+  transcript: RecommendedTranscript,
 
   decoys: Vec<Decoys>,
 
@@ -58,7 +58,7 @@ impl SignableTransaction {
     self,
     rpc: &Rpc,
     keys: MultisigKeys<Ed25519>,
-    mut transcript: Transcript,
+    mut transcript: RecommendedTranscript,
     height: usize,
     mut included: Vec<u16>
   ) -> Result<TransactionMachine, TransactionError> {

coins/monero/tests/send.rs

@@ -27,7 +27,9 @@ mod rpc;
 use crate::rpc::{rpc, mine_block};
 
 #[cfg(feature = "multisig")]
-use monero_serai::frost::{Transcript, Ed25519};
+use transcript::RecommendedTranscript;
+#[cfg(feature = "multisig")]
+use monero_serai::frost::Ed25519;
 
 lazy_static! {
   static ref SEQUENTIAL: Mutex<()> = Mutex::new(());
@@ -147,7 +149,7 @@ async fn send_core(test: usize, multisig: bool) {
             signable.clone().multisig(
               &rpc,
               (*keys[&i]).clone(),
-              Transcript::new(b"Monero Serai Test Transaction"),
+              RecommendedTranscript::new(b"Monero Serai Test Transaction"),
               rpc.get_height().await.unwrap() - 10,
               (1 ..= THRESHOLD).collect::<Vec<_>>()
             ).await.unwrap()

crypto/transcript/Cargo.toml

@@ -11,7 +11,9 @@ edition = "2021"
 [dependencies]
 digest = "0.10"
 
+blake2 = { version = "0.10", optional = true }
 merlin = { version = "3", optional = true }
 
 [features]
+recommended = ["blake2"]
 merlin = ["dep:merlin"]

crypto/transcript/src/lib.rs

@@ -74,3 +74,6 @@ impl<D: Digest + Clone> Transcript for DigestTranscript<D>
     seed
   }
 }
+
+#[cfg(feature = "recommended")]
+pub type RecommendedTranscript = DigestTranscript<blake2::Blake2b512>;

processor/Cargo.toml

@@ -18,7 +18,7 @@ serde_json = "1.0"
 curve25519-dalek = { version = "3", features = ["std"] }
 blake2 = "0.10"
 
-transcript = { package = "transcript-trait", path = "../crypto/transcript" }
+transcript = { package = "transcript-trait", path = "../crypto/transcript", features = ["recommended"] }
 dalek-ff-group = { path = "../crypto/dalek-ff-group" }
 frost = { package = "modular-frost", path = "../crypto/frost" }
 

processor/src/coins/monero.rs

@@ -5,6 +5,7 @@ use async_trait::async_trait;
 use curve25519_dalek::{constants::ED25519_BASEPOINT_TABLE, scalar::Scalar};
 
 use dalek_ff_group as dfg;
+use transcript::RecommendedTranscript;
 use frost::MultisigKeys;
 
 use monero::{PublicKey, network::Network, util::address::Address};
@@ -15,7 +16,7 @@ use monero_serai::{
   wallet::{Fee, SpendableOutput, SignableTransaction as MSignableTransaction, TransactionMachine}
 };
 
-use crate::{Transcript, CoinError, Output as OutputTrait, Coin, view_key};
+use crate::{CoinError, Output as OutputTrait, Coin, view_key};
 
 #[derive(Clone, Debug)]
 pub struct Output(SpendableOutput);
@@ -51,7 +52,7 @@ impl From<SpendableOutput> for Output {
 #[derive(Debug)]
 pub struct SignableTransaction(
   Arc<MultisigKeys<Ed25519>>,
-  Transcript,
+  RecommendedTranscript,
   usize,
   MSignableTransaction
 );
@@ -129,7 +130,7 @@ impl Coin for Monero {
   async fn prepare_send(
     &self,
     keys: Arc<MultisigKeys<Ed25519>>,
-    transcript: Transcript,
+    transcript: RecommendedTranscript,
     height: usize,
     mut inputs: Vec<Output>,
     payments: &[(Address, u64)],

processor/src/lib.rs

@@ -5,7 +5,7 @@ use thiserror::Error;
 
 use frost::{Curve, FrostError, MultisigKeys, sign::PreprocessMachine};
 
-pub(crate) use monero_serai::frost::Transcript;
+use transcript::RecommendedTranscript;
 
 mod coins;
 mod wallet;
@@ -80,7 +80,7 @@ pub trait Coin {
   async fn prepare_send(
     &self,
     keys: Arc<MultisigKeys<Self::Curve>>,
-    transcript: Transcript,
+    transcript: RecommendedTranscript,
     height: usize,
     inputs: Vec<Self::Output>,
     payments: &[(Self::Address, u64)],

processor/src/wallet.rs

@@ -2,11 +2,11 @@ use std::{sync::Arc, collections::HashMap};
 
 use rand_core::OsRng;
 
-use transcript::Transcript as TranscriptTrait;
+use transcript::{Transcript, RecommendedTranscript};
 
 use frost::{Curve, MultisigKeys, sign::{PreprocessMachine, SignMachine, SignatureMachine}};
 
-use crate::{Transcript, CoinError, SignError, Output, Coin, Network};
+use crate::{CoinError, SignError, Output, Coin, Network};
 
 pub struct WalletKeys<C: Curve> {
   keys: MultisigKeys<C>,
@@ -28,7 +28,7 @@ impl<C: Curve> WalletKeys<C> {
   // function as well, although that degree of influence means key gen is broken already
   fn bind(&self, chain: &[u8]) -> MultisigKeys<C> {
     const DST: &[u8] = b"Serai Processor Wallet Chain Bind";
-    let mut transcript = Transcript::new(DST);
+    let mut transcript = RecommendedTranscript::new(DST);
     transcript.append_message(b"chain", chain);
     transcript.append_message(b"curve", C::ID);
     transcript.append_message(b"group_key", &C::G_to_bytes(&self.keys.group_key()));
@@ -308,7 +308,7 @@ impl<D: CoinDb, C: Coin> Wallet<D, C> {
         }
 
         // Create the transcript for this transaction
-        let mut transcript = Transcript::new(b"Serai Processor Wallet Send");
+        let mut transcript = RecommendedTranscript::new(b"Serai Processor Wallet Send");
         transcript.append_message(
           b"canonical_height",
           &u64::try_from(canonical).unwrap().to_le_bytes()