feat(rln-relay): adds rln identifier to the RateLimitProof (#1219)

* adds rln identifier to the RateLimitProof

* enables rln-relay compilation for wakunode2

* unifies the two RateLimitProof types

* a minor update

Co-authored-by: G <28568419+s1fr0@users.noreply.github.com>

waku/v2/node/wakunode2.nim

@@ -36,7 +36,7 @@ import
 export
   wakunode2_types
 
-when defined(rln):
+when defined(rln) or defined(rlnzerokit):
   import ../protocol/waku_rln_relay/waku_rln_relay_utils
 
 declarePublicCounter waku_node_messages, "number of messages received", ["type"]
@@ -1066,7 +1066,7 @@ when isMainModule:
     # Keepalive mounted on all nodes
     waitFor mountLibp2pPing(node)
     
-    when defined(rln): 
+    when defined(rln) or defined(rlnzerokit): 
       if conf.rlnRelay:
         let res = node.mountRlnRelay(conf)
         if res.isErr():

waku/v2/protocol/waku_rln_relay/waku_rln_relay_types.nim

@@ -32,6 +32,7 @@ type
   MerkleNode* = array[32, byte] # Each node of the Merkle tee is a Poseidon hash which is a 32 byte value
   Nullifier* = array[32, byte]
   Epoch* = array[32, byte]
+  RlnIdentifier* = array[32, byte]
 
 when defined(rln) or (not defined(rln) and not defined(rlnzerokit)):
   type
@@ -39,7 +40,7 @@ when defined(rln) or (not defined(rln) and not defined(rlnzerokit)):
 when defined(rlnzerokit):
   type 
     ZKSNARK* = array[128, byte]
-    RlnIdentifier* = array[32, byte]
+  
 
 # Custom data types defined for waku rln relay -------------------------
 type MembershipKeyPair* = object
@@ -51,27 +52,7 @@ type MembershipKeyPair* = object
   # more details in https://hackmd.io/tMTLMYmTR5eynw2lwK9n1w?view#Membership
   idCommitment*: IDCommitment
 
-when defined(rln) or (not defined(rln) and not defined(rlnzerokit)):
+type RateLimitProof* = object
-  type RateLimitProof* = object
-    ## RateLimitProof holds the public inputs to rln circuit as
-    ## defined in https://hackmd.io/tMTLMYmTR5eynw2lwK9n1w?view#Public-Inputs
-    ## the `proof` field carries the actual zkSNARK proof
-    proof*: ZKSNARK
-    ## the root of Merkle tree used for the generation of the `proof`
-    merkleRoot*: MerkleNode
-    ## the epoch used for the generation of the `proof`
-    epoch*: Epoch
-    ## shareX and shareY are shares of user's identity key
-    ## these shares are created using Shamir secret sharing scheme
-    ## see details in https://hackmd.io/tMTLMYmTR5eynw2lwK9n1w?view#Linear-Equation-amp-SSS
-    shareX*: MerkleNode
-    shareY*: MerkleNode
-    ## nullifier enables linking two messages published during the same epoch
-    ## see details in https://hackmd.io/tMTLMYmTR5eynw2lwK9n1w?view#Nullifiers
-    nullifier*: Nullifier
-
-when defined(rlnzerokit):
-  type RateLimitProof* = object
   ## RateLimitProof holds the public inputs to rln circuit as
   ## defined in https://hackmd.io/tMTLMYmTR5eynw2lwK9n1w?view#Public-Inputs
   ## the `proof` field carries the actual zkSNARK proof
@@ -183,7 +164,6 @@ proc init*(T: type RateLimitProof, buffer: seq[byte]): ProtoResult[T] =
   discard ? pb.getField(6, nullifier)
   discard nsp.nullifier.copyFrom(nullifier)
   
-  when defined(rlnzerokit):
   var rlnIdentifier: seq[byte]
   discard ? pb.getField(7, rlnIdentifier)
   discard nsp.rlnIdentifier.copyFrom(rlnIdentifier)
@@ -199,8 +179,6 @@ proc encode*(nsp: RateLimitProof): ProtoBuffer =
   output.write3(4, nsp.shareX)
   output.write3(5, nsp.shareY)
   output.write3(6, nsp.nullifier)
-
-  when defined(rlnzerokit):
   output.write3(7, nsp.rlnIdentifier)
 
   output.finish3()