add ecash params to api

common/nym_offline_compact_ecash/src/impls/clone.rs

@@ -1,5 +1,6 @@
 use crate::scheme::withdrawal::WithdrawalRequest;
 use crate::scheme::EcashCredential;
+use crate::setup::Parameters;
 use crate::traits::Bytable;
 
 macro_rules! impl_clone {
@@ -14,3 +15,4 @@ macro_rules! impl_clone {
 
 impl_clone!(WithdrawalRequest);
 impl_clone!(EcashCredential);
+impl_clone!(Parameters);

common/nym_offline_compact_ecash/src/impls/serde.rs

@@ -1,4 +1,5 @@
 use crate::scheme::EcashCredential;
+use crate::setup::Parameters;
 use crate::traits::Base58;
 use crate::VerificationKeyAuth;
 use serde::de::Unexpected;
@@ -49,3 +50,4 @@ macro_rules! impl_serde {
 impl_serde!(WithdrawalRequest, V1);
 impl_serde!(EcashCredential, V2);
 impl_serde!(VerificationKeyAuth, V3);
+impl_serde!(Parameters, V4);

common/nym_offline_compact_ecash/src/scheme/setup.rs

@@ -6,7 +6,9 @@ use group::Curve;
 use rand::thread_rng;
 
 use crate::error::{CompactEcashError, Result};
+use crate::traits::Bytable;
 use crate::utils::{hash_g1, try_deserialize_g2_projective, Signature};
+use crate::Base58;
 
 const ATTRIBUTES_LEN: usize = 3;
 
@@ -210,6 +212,19 @@ impl TryFrom<&[u8]> for Parameters {
         })
     }
 }
+
+impl Bytable for Parameters {
+    fn to_byte_vec(&self) -> Vec<u8> {
+        self.to_bytes().to_vec()
+    }
+
+    fn try_from_byte_slice(slice: &[u8]) -> std::result::Result<Self, CompactEcashError> {
+        Self::try_from(slice)
+    }
+}
+
+impl Base58 for Parameters {}
+
 pub fn setup(ll: u64) -> Parameters {
     let grp = GroupParameters::new().unwrap();
     let x = grp.random_scalar();

nym-api/nym-api-requests/src/coconut.rs

@@ -6,6 +6,7 @@ use getset::{CopyGetters, Getters};
 use nym_compact_ecash::{
     error::CompactEcashError,
     scheme::{withdrawal::WithdrawalRequest, EcashCredential},
+    setup::Parameters,
     VerificationKeyAuth,
 };
 use serde::{Deserialize, Serialize};
@@ -164,3 +165,16 @@ impl CosmosAddressResponse {
         CosmosAddressResponse { addr }
     }
 }
+
+#[derive(Serialize, Deserialize)]
+pub struct EcashParametersResponse {
+    pub params: Parameters,
+}
+
+impl EcashParametersResponse {
+    pub fn new(params: &Parameters) -> EcashParametersResponse {
+        EcashParametersResponse {
+            params: params.clone(),
+        }
+    }
+}

nym-api/src/coconut/mod.rs

@@ -10,7 +10,8 @@ use crate::support::storage::NymApiStorage;
 use getset::{CopyGetters, Getters};
 use keypair::KeyPair;
 use nym_api_requests::coconut::{
-    BlindSignRequestBody, BlindedSignatureResponse, VerifyCredentialBody, VerifyCredentialResponse,
+    BlindSignRequestBody, BlindedSignatureResponse, EcashParametersResponse, VerifyCredentialBody,
+    VerifyCredentialResponse,
 };
 use nym_coconut::VerificationKey;
 use nym_coconut_bandwidth_contract_common::spend_credential::{
@@ -22,7 +23,7 @@ use nym_compact_ecash::error::CompactEcashError;
 use nym_compact_ecash::scheme::keygen::{KeyPairAuth, SecretKeyAuth};
 use nym_compact_ecash::scheme::withdrawal::WithdrawalRequest;
 use nym_compact_ecash::scheme::EcashCredential;
-use nym_compact_ecash::setup::GroupParameters;
+use nym_compact_ecash::setup::{setup, GroupParameters, Parameters};
 use nym_compact_ecash::utils::BlindedSignature;
 use nym_compact_ecash::{PublicKeyUser, VerificationKeyAuth};
 use nym_config::defaults::NYM_API_VERSION;
@@ -54,6 +55,7 @@ pub(crate) mod tests;
 pub struct State {
     client: Arc<dyn LocalClient + Send + Sync>,
     mix_denom: String,
+    ecash_params: Parameters,
     key_pair: KeyPair,
     comm_channel: Arc<dyn APICommunicationChannel + Send + Sync>,
     storage: NymApiStorage,
@@ -78,6 +80,7 @@ impl State {
         Self {
             client,
             mix_denom,
+            ecash_params: setup(100),
             key_pair,
             comm_channel,
             storage,
@@ -193,7 +196,11 @@ impl InternalSignRequest {
             rocket.manage(state).mount(
                 // this format! is so ugly...
                 format!("/{}/{}/{}", NYM_API_VERSION, COCONUT_ROUTES, BANDWIDTH),
-                routes![post_blind_sign, verify_bandwidth_credential],
+                routes![
+                    post_blind_sign,
+                    verify_bandwidth_credential,
+                    ecash_parameters
+                ],
             )
         })
     }
@@ -284,6 +291,11 @@ pub async fn verify_bandwidth_credential(
     Ok(Json(VerifyCredentialResponse::new(true)))
 }
 
+#[get("/ecash-parameters")]
+pub async fn ecash_parameters(state: &RocketState<State>) -> Result<Json<EcashParametersResponse>> {
+    Ok(Json(EcashParametersResponse::new(&state.ecash_params)))
+}
+
 // #[post("/verify-bandwidth-credential", data = "<verify_credential_body>")]
 // pub async fn verify_bandwidth_credential(
 //     verify_credential_body: Json<VerifyCredentialBody>,