revert rand changes, update changelog and book

Cargo.lock

@@ -1111,8 +1111,10 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "8fc3cb4d91f53b50155bdcfd23f6a4c39ae1969c2ae85982b135750cccaf5fce"
 dependencies = [
  "cfg-if 1.0.0",
+ "js-sys",
  "libc",
  "wasi 0.9.0+wasi-snapshot-preview1",
+ "wasm-bindgen",
 ]
 
 [[package]]

changelogs/unreleased/1071-dark64

@@ -1 +1 @@
-Support for ark-groth16 implementation
+Support for the `groth16` scheme using the ark backend, support the usage of the `bls12_381` curve with the `gm17` and `marlin` scheme

zokrates_book/src/toolbox/proving_schemes.md

@@ -23,12 +23,12 @@ When not using the default, the CLI flag has to be provided for the following co
 
 ZoKrates supports different proving schemes. We identify the schemes by the reference to the paper that introduced them. Currently the options available are:
 
-| Scheme | CLI flag | Curves | Universal |
-| ---- | -------- | ------ | ------------|
-| [G16](https://eprint.iacr.org/2016/260) | `--proving-scheme g16` | ALTBN_128, BLS12_381 | No |
-| [GM17](https://eprint.iacr.org/2017/540) | `--proving-scheme gm17` | ALTBN_128, BLS12_377, BW6_761 | No |
-| [Marlin](https://eprint.iacr.org/2019/1047) | `--proving-scheme marlin` | ALTBN_128, BLS12_377, BW6_761 | Yes |
-| [PGHR13](https://eprint.iacr.org/2013/279) | `--proving-scheme pghr13` | ALTBN_128 | No |
+| Scheme | CLI flag | Curves                                   | Universal |
+| ---- | -------- |------------------------------------------| ------------|
+| [G16](https://eprint.iacr.org/2016/260) | `--proving-scheme g16` | ALTBN_128, BLS12_381                     | No |
+| [GM17](https://eprint.iacr.org/2017/540) | `--proving-scheme gm17` | ALTBN_128, BLS12_381, BLS12_377, BW6_761 | No |
+| [Marlin](https://eprint.iacr.org/2019/1047) | `--proving-scheme marlin` | ALTBN_128, BLS12_381, BLS12_377, BW6_761 | Yes |
+| [PGHR13](https://eprint.iacr.org/2013/279) | `--proving-scheme pghr13` | ALTBN_128                                | No |
 
 All schemes have a circuit-specific setup phase called `setup`. Universal schemes also feature a preliminary, circuit-agnostic step called `universal-setup`. The advantage of universal schemes is that only the `universal-setup` step requires trust, so that it can be run a single time and reused trustlessly for many programs.
 
@@ -45,11 +45,11 @@ When not using the default, the CLI flag has to be provided for the following co
 
 ZoKrates supports multiple backends. The options are the following:
 
-| Backend | CLI flag | Proving schemes | Curves |
-| ---- | -------- | --------------- | ------ |
-| Bellman | `--backend bellman` | G16 | ALTBN_128, BLS12_381 |
-| Libsnark | `--backend libsnark` | GM17, PGHR13 | ALTBN_128 |
-| Ark | `--backend ark` | GM17, MARLIN | ALTBN_128, BLS12_377, BW6_761 |
+| Backend | CLI flag | Proving schemes   | Curves                                   |
+| ---- | -------- |-------------------|------------------------------------------|
+| Bellman | `--backend bellman` | G16               | ALTBN_128, BLS12_381                     |
+| Libsnark | `--backend libsnark` | GM17, PGHR13      | ALTBN_128                                |
+| Ark | `--backend ark` | G16, GM17, MARLIN | ALTBN_128, BLS12_381, BLS12_377, BW6_761 |
 
 Default: `bellman`
 

zokrates_core/Cargo.toml

@@ -35,7 +35,7 @@ zokrates_common = { path = "../zokrates_common" }
 zokrates_embed = { version = "0.1.0", path = "../zokrates_embed" }
 getrandom = { version = "0.2", features = ["js"] }
 rand_0_4 = { version = "0.4", package = "rand" }
-rand_0_7 = { version = "0.7", package = "rand" }
+rand_0_7 = { version = "0.7", package = "rand", features = ["wasm-bindgen"] }
 csv = "1"
 phase2 = { git = "https://github.com/Zokrates/phase2", default-features = false }
 

zokrates_core/src/proof_system/ark/gm17.rs

@@ -7,7 +7,7 @@ use ark_serialize::{CanonicalDeserialize, CanonicalSerialize};
 use zokrates_field::{ArkFieldExtensions, Bw6_761Field, Field};
 
 use crate::ir::{ProgIterator, Statement, Witness};
-use crate::proof_system::ark::{get_random_seed, Computation};
+use crate::proof_system::ark::Computation;
 use crate::proof_system::ark::{parse_fr, parse_g1, parse_g2, parse_g2_fq};
 use crate::proof_system::ark::{serialization, Ark};
 use crate::proof_system::gm17::{ProofPoints, VerificationKey, GM17};
@@ -22,7 +22,7 @@ impl<T: Field + ArkFieldExtensions + NotBw6_761Field> NonUniversalBackend<T, GM1
     ) -> SetupKeypair<<GM17 as Scheme<T>>::VerificationKey> {
         let computation = Computation::without_witness(program);
 
-        let rng = &mut rand_0_7::rngs::StdRng::from_seed(get_random_seed().unwrap());
+        let rng = &mut rand_0_7::rngs::StdRng::from_entropy();
         let (pk, vk) = ArkGM17::<T::ArkEngine>::circuit_specific_setup(computation, rng).unwrap();
 
         let mut pk_vec: Vec<u8> = Vec::new();
@@ -60,7 +60,7 @@ impl<T: Field + ArkFieldExtensions + NotBw6_761Field> Backend<T, GM17> for Ark {
         )
         .unwrap();
 
-        let rng = &mut rand_0_7::rngs::StdRng::from_seed(get_random_seed().unwrap());
+        let rng = &mut rand_0_7::rngs::StdRng::from_entropy();
         let proof = ArkGM17::<T::ArkEngine>::prove(&pk, computation, rng).unwrap();
 
         let proof_points = ProofPoints {
@@ -118,7 +118,7 @@ impl NonUniversalBackend<Bw6_761Field, GM17> for Ark {
     ) -> SetupKeypair<<GM17 as Scheme<Bw6_761Field>>::VerificationKey> {
         let computation = Computation::without_witness(program);
 
-        let rng = &mut rand_0_7::rngs::StdRng::from_seed(get_random_seed().unwrap());
+        let rng = &mut rand_0_7::rngs::StdRng::from_entropy();
         let (pk, vk) = ArkGM17::<BW6_761>::circuit_specific_setup(computation, rng).unwrap();
 
         let mut pk_vec: Vec<u8> = Vec::new();
@@ -157,7 +157,7 @@ impl Backend<Bw6_761Field, GM17> for Ark {
             )
                 .unwrap();
 
-        let rng = &mut rand_0_7::rngs::StdRng::from_seed(get_random_seed().unwrap());
+        let rng = &mut rand_0_7::rngs::StdRng::from_entropy();
         let proof = ArkGM17::<BW6_761>::prove(&pk, computation, rng).unwrap();
 
         let proof_points = ProofPoints {

zokrates_core/src/proof_system/ark/groth16.rs

@@ -10,7 +10,7 @@ use zokrates_field::{ArkFieldExtensions, Bw6_761Field};
 
 use crate::ir::{ProgIterator, Statement, Witness};
 use crate::proof_system::ark::Computation;
-use crate::proof_system::ark::{get_random_seed, parse_fr, serialization, Ark};
+use crate::proof_system::ark::{parse_fr, serialization, Ark};
 use crate::proof_system::ark::{parse_g1, parse_g2};
 use crate::proof_system::groth16::{ProofPoints, VerificationKey, G16};
 use crate::proof_system::Scheme;
@@ -40,7 +40,7 @@ impl<T: Field + ArkFieldExtensions + NotBw6_761Field> Backend<T, G16> for Ark {
         )
         .unwrap();
 
-        let rng = &mut rand_0_7::rngs::StdRng::from_seed(get_random_seed().unwrap());
+        let rng = &mut rand_0_7::rngs::StdRng::from_entropy();
         let proof = Groth16::<T::ArkEngine>::prove(&pk, computation, rng).unwrap();
 
         let proof_points = ProofPoints {
@@ -97,7 +97,7 @@ impl<T: Field + ArkFieldExtensions + NotBw6_761Field> NonUniversalBackend<T, G16
 
         let computation = Computation::without_witness(program);
 
-        let rng = &mut rand_0_7::rngs::StdRng::from_seed(get_random_seed().unwrap());
+        let rng = &mut rand_0_7::rngs::StdRng::from_entropy();
         let (pk, vk) = Groth16::<T::ArkEngine>::circuit_specific_setup(computation, rng).unwrap();
 
         let mut pk_vec: Vec<u8> = Vec::new();
@@ -134,7 +134,7 @@ impl Backend<Bw6_761Field, G16> for Ark {
         let pk =
             ProvingKey::<BW6_761>::deserialize_uncompressed(&mut proving_key.as_slice()).unwrap();
 
-        let rng = &mut rand_0_7::rngs::StdRng::from_seed(get_random_seed().unwrap());
+        let rng = &mut rand_0_7::rngs::StdRng::from_entropy();
         let proof = Groth16::<BW6_761>::prove(&pk, computation, rng).unwrap();
 
         let proof_points = ProofPoints {
@@ -191,7 +191,7 @@ impl NonUniversalBackend<Bw6_761Field, G16> for Ark {
 
         let computation = Computation::without_witness(program);
 
-        let rng = &mut rand_0_7::rngs::StdRng::from_seed(get_random_seed().unwrap());
+        let rng = &mut rand_0_7::rngs::StdRng::from_entropy();
         let (pk, vk) = Groth16::<BW6_761>::circuit_specific_setup(computation, rng).unwrap();
 
         let mut pk_vec: Vec<u8> = Vec::new();

zokrates_core/src/proof_system/ark/mod.rs

@@ -141,12 +141,6 @@ impl<T: Field + ArkFieldExtensions, I: IntoIterator<Item = Statement<T>>> ProgIt
     }
 }
 
-pub fn get_random_seed() -> Result<[u8; 32], getrandom::Error> {
-    let mut seed = [0u8; 32];
-    getrandom::getrandom(&mut seed)?;
-    Ok(seed)
-}
-
 impl<T: Field + ArkFieldExtensions, I: IntoIterator<Item = Statement<T>>> Computation<T, I> {
     pub fn public_inputs_values(&self) -> Vec<<T::ArkEngine as PairingEngine>::Fr> {
         self.program