Merge pull request paritytech#120 from subspace/local-challenge-from-…

…signature

Derive local challenge from signature instead of public key hash

crates/pallet-offences-subspace/Cargo.toml

@@ -25,7 +25,7 @@ sp-std = { version = "4.0.0-dev", default-features = false, git = "https://githu
 [dev-dependencies]
 sp-io = { version = "4.0.0-dev", git = "https://github.com/paritytech/substrate", rev = "26d69bcbe26f6b463e9374e1b1c54c3067fb6131" }
 sp-core = { version = "4.0.0-dev", git = "https://github.com/paritytech/substrate", rev = "26d69bcbe26f6b463e9374e1b1c54c3067fb6131" }
-schnorrkel = "0.10.1"
+schnorrkel = "0.9.1"
 
 [features]
 default = ["std"]

crates/pallet-subspace/src/mock.rs

@@ -35,7 +35,7 @@ use sp_runtime::{
     Perbill,
 };
 use subspace_core_primitives::{
-    ArchivedBlockProgress, LastArchivedBlock, Piece, RootBlock, Sha256Hash, Tag,
+    ArchivedBlockProgress, LastArchivedBlock, Piece, RootBlock, Sha256Hash, Signature, Tag,
 };
 use subspace_solving::{SubspaceCodec, SOLUTION_SIGNING_CONTEXT};
 
@@ -194,17 +194,18 @@ pub fn go_to_block(keypair: &Keypair, block: u64, slot: u64) {
     let subspace_solving = SubspaceCodec::new(&keypair.public);
     let ctx = schnorrkel::context::signing_context(SOLUTION_SIGNING_CONTEXT);
     let piece_index = 0;
-    let mut piece = Piece::default();
-    subspace_solving.encode(piece_index, &mut piece).unwrap();
-    let tag: Tag = subspace_solving::create_tag(&piece, Subspace::salt().to_le_bytes());
+    let mut encoding = Piece::default();
+    subspace_solving.encode(piece_index, &mut encoding).unwrap();
+    let tag: Tag = subspace_solving::create_tag(&encoding, Subspace::salt().to_le_bytes());
 
     let pre_digest = make_pre_digest(
         slot.into(),
         Solution {
             public_key: FarmerPublicKey::from_slice(&keypair.public.to_bytes()),
             piece_index: 0,
-            encoding: piece.to_vec(),
-            signature: keypair.sign(ctx.bytes(&tag)).to_bytes().to_vec(),
+            encoding,
+            signature: keypair.sign(ctx.bytes(&tag)).to_bytes().into(),
+            local_challenge: Signature::default(),
             tag,
         },
     );
@@ -254,7 +255,7 @@ pub fn generate_equivocation_proof(
     let tag: Tag = [(current_block % 8) as u8; 8];
 
     let public_key = FarmerPublicKey::from_slice(&keypair.public.to_bytes());
-    let signature = keypair.sign(ctx.bytes(&tag)).to_bytes().to_vec();
+    let signature = keypair.sign(ctx.bytes(&tag)).to_bytes();
 
     let make_header = |piece_index| {
         let parent_hash = System::parent_hash();
@@ -263,8 +264,9 @@ pub fn generate_equivocation_proof(
             Solution {
                 public_key: public_key.clone(),
                 piece_index,
-                encoding: encoding.to_vec(),
-                signature: signature.clone(),
+                encoding,
+                signature: signature.into(),
+                local_challenge: Signature::default(),
                 tag,
             },
         );

crates/sc-consensus-subspace-rpc/src/lib.rs

@@ -304,6 +304,7 @@ where
                                     piece_index: solution.piece_index,
                                     encoding: solution.encoding,
                                     signature: solution.signature,
+                                    local_challenge: solution.local_challenge,
                                     tag: solution.tag,
                                 };
 
@@ -326,7 +327,7 @@ where
                     // This will be sent to the farmer
                     Ok(Ok(SlotInfo {
                         slot_number: new_slot_info.slot.into(),
-                        challenge: new_slot_info.challenge,
+                        global_challenge: new_slot_info.global_challenge,
                         salt: new_slot_info.salt,
                         next_salt: new_slot_info.next_salt,
                         solution_range: new_slot_info.solution_range,

crates/sc-consensus-subspace/src/authorship.rs

@@ -136,7 +136,7 @@ where
 
         let new_slot_info = NewSlotInfo {
             slot,
-            challenge: subspace_solving::derive_global_challenge(&epoch_randomness, slot),
+            global_challenge: subspace_solving::derive_global_challenge(&epoch_randomness, slot),
             salt: salt.to_le_bytes(),
             // TODO: This will not be the correct way in the future once salt is no longer
             //  just an incremented number

crates/sc-consensus-subspace/src/lib.rs

@@ -113,7 +113,7 @@ use std::{borrow::Cow, collections::HashMap, pin::Pin, sync::Arc, time::Duration
 pub use subspace_archiving::archiver::ArchivedSegment;
 use subspace_archiving::archiver::{BlockArchiver, ObjectArchiver};
 use subspace_archiving::pre_genesis_data;
-use subspace_core_primitives::{Randomness, RootBlock, Salt};
+use subspace_core_primitives::{Randomness, RootBlock, Salt, Tag};
 use subspace_solving::SOLUTION_SIGNING_CONTEXT;
 
 mod archiver;
@@ -130,8 +130,8 @@ mod verification;
 pub struct NewSlotInfo {
     /// Slot
     pub slot: Slot,
-    /// Slot challenge
-    pub challenge: [u8; 8],
+    /// Global slot challenge
+    pub global_challenge: Tag,
     /// Salt
     pub salt: Salt,
     /// Salt for the next eon
@@ -264,12 +264,12 @@ pub enum Error<B: BlockT> {
     /// Bad solution signature
     #[display(fmt = "Bad solution signature on slot {:?}: {:?}", _0, _1)]
     BadSolutionSignature(Slot, schnorrkel::SignatureError),
+    /// Bad local challenge
+    #[display(fmt = "Local challenge is invalid for slot {}: {}", _0, _1)]
+    BadLocalChallenge(Slot, schnorrkel::SignatureError),
     /// Solution is outside of solution range
     #[display(fmt = "Solution is outside of solution range for slot {}", _0)]
     OutsideOfSolutionRange(Slot),
-    /// Encoding is of wrong size
-    #[display(fmt = "Encoding is of the wrong size")]
-    EncodingOfWrongSize,
     /// Invalid encoding of a piece
     #[display(fmt = "Invalid encoding for slot {}", _0)]
     InvalidEncoding(Slot),