General Improvements (#268)

* Move `elliptic-curve` implementation to points to allow `Zeroize`

* Simplify `Ristretto255::random_scalar` implementation

* Fix `Ristretto255` deserialization

* Remove unnecessary check in `Ristretto255::random_scalar`

* Base `X25519` implementation on `curve25519-dalek`

* Constrain public and secret key to `Copy`

* Replace manual `ZeroizeOnDrop` implementation with `derive`

* Update dependencies

* Add `warn(unused_crate_dependencies)`

* Sync crate feature naming with `voprf`

* Remove unnecessary dependency crate features

* Never produce a zero scalar

* Rename `OprfGroup` to `OprfCs`

* Rename `TripleDH` to `TripleDh`

* Remove `slow-hash` crate feature

* Rename `NoOpHash` to `Identity`

* Rename `SlowHash` to `Ksf`

* Move `KeyExchange` type definitions down

* Deserialize secret and public keys from slices

* Remove `PrivateKey::from_bytes`

* Rename `From/ToBytes` to `De/Serialize`

* Re-export `serde_` as `serde`

* Custom `De/Serialize` implementation for keys

* Remove custom `De/Serialize` implementation

* Run Taplo v0.6

.github/workflows/main.yml

@@ -13,16 +13,16 @@ jobs:
       fail-fast: false
       matrix:
         backend_feature:
-          - --features ristretto255_u64,ristretto255_voprf
-          - --features ristretto255_u32,ristretto255_voprf
-          - 
-          - --features x25519_u64,ristretto255_u64,ristretto255_voprf
-          - --features x25519_u32,ristretto255_u32,ristretto255_voprf
-          - --features x25519_u64
-          - --features x25519_u32
+          - --features ristretto255-u64,ristretto255-voprf
+          - --features ristretto255-u32,ristretto255-voprf
+          -
+          - --features x25519-u64,ristretto255-u64,ristretto255-voprf
+          - --features x25519-u32,ristretto255-u32,ristretto255-voprf
+          - --features x25519-u64
+          - --features x25519-u32
         frontend_feature:
-          - 
-          - --features slow-hash
+          -
+          - --features argon2
           - --features serde
         toolchain:
           - stable
@@ -61,13 +61,13 @@ jobs:
           # 32-bit x86
           - i686-unknown-linux-gnu
         backend_feature:
-          - --features ristretto255_u64,ristretto255_voprf
-          - --features ristretto255_u32,ristretto255_voprf
-          - 
-          - x25519_u64,ristretto255_u64,ristretto255_voprf
-          - x25519_u32,ristretto255_u64,ristretto255_voprf
-          - x25519_u64
-          - x25519_u32
+          - --features ristretto255-u64,ristretto255-voprf
+          - --features ristretto255-u32,ristretto255-voprf
+          -
+          - x25519-u64,ristretto255-u64,ristretto255-voprf
+          - x25519-u32,ristretto255-u64,ristretto255-voprf
+          - x25519-u64
+          - x25519-u32
     steps:
       - uses: actions/checkout@v2
       - uses: hecrj/setup-rust-action@v1
@@ -135,15 +135,15 @@ jobs:
           # for any no_std target
           - thumbv6m-none-eabi
         backend_feature:
-          - ristretto255_u64,ristretto255_voprf
-          - ristretto255_u32,ristretto255_voprf
-          - 
-          - x25519_u64,ristretto255_u64,ristretto255_voprf
-          - x25519_u32,ristretto255_u32,ristretto255_voprf
-          - x25519_u64
-          - x25519_u32
+          - ristretto255-u64,ristretto255-voprf
+          - ristretto255-u32,ristretto255-voprf
+          -
+          - x25519-u64,ristretto255-u64,ristretto255-voprf
+          - x25519-u32,ristretto255-u32,ristretto255-voprf
+          - x25519-u64
+          - x25519-u32
         frontend_feature:
-          - slow-hash
+          - argon2
           - serde
     steps:
       - uses: actions/checkout@v2
@@ -158,13 +158,13 @@ jobs:
       fail-fast: false
       matrix:
         backend_feature:
-          - --features ristretto255_u64,ristretto255_voprf
-          - --features ristretto255_u32,ristretto255_voprf
-          - 
-          - --features x25519_u64,ristretto255_u64,ristretto255_voprf
-          - --features x25519_u32,ristretto255_u32,ristretto255_voprf
-          - --features x25519_u32
-          - --features x25519_u32
+          - --features ristretto255-u64,ristretto255-voprf
+          - --features ristretto255-u32,ristretto255-voprf
+          -
+          - --features x25519-u64,ristretto255-u64,ristretto255-voprf
+          - --features x25519-u32,ristretto255-u32,ristretto255-voprf
+          - --features x25519-u32
+          - --features x25519-u32
     steps:
       - name: Checkout sources
         uses: actions/checkout@v2
@@ -201,7 +201,7 @@ jobs:
         uses: actions-rs/cargo@v1
         with:
           command: clippy
-          args: --all-targets --features slow-hash,std,x25519_u64 -- -D warnings
+          args: --all-targets --features argon2,std,x25519-u64 -- -D warnings
 
       - name: Run cargo doc
         uses: actions-rs/cargo@v1
@@ -209,7 +209,7 @@ jobs:
           RUSTDOCFLAGS: -D warnings
         with:
           command: doc
-          args: --no-deps --document-private-items --features slow-hash,std,x25519_u64
+          args: --no-deps --document-private-items --features argon2,std,x25519-u64
 
   format:
     name: cargo fmt