KZG Key Generation, Save, Load

examples/kzg_keygen_tools.rs

@@ -0,0 +1,91 @@
+use std::{
+  fs::OpenOptions,
+  io::{BufReader, BufWriter},
+};
+
+use halo2curves::bn256;
+use nova_snark::{
+  provider::{
+    check_sanity_of_ptau_file,
+    hyperkzg::{CommitmentEngine, CommitmentKey},
+    Bn256EngineKZG,
+  },
+  traits::commitment::CommitmentEngineTrait,
+};
+use rand_core::OsRng;
+
+type E = Bn256EngineKZG;
+
+const KZG_KEY_DIR: &str = "/tmp/";
+
+pub fn get_key_file_path(num_gens: usize) -> String {
+  let id = std::any::type_name::<E>().chars()
+        .filter(|c| c.is_alphanumeric())  // Keep only alphanumeric characters
+        .collect::<String>();
+
+  let base_dir = KZG_KEY_DIR.trim_end_matches("/");
+  format!("{}/kzg_{}_{}.keys", base_dir, id, num_gens)
+}
+
+const LABEL: &[u8; 4] = b"test";
+
+const MAX_NUM_GENS: usize = 1 << 21;
+
+macro_rules! timeit {
+  ($e:expr) => {{
+    let start = std::time::Instant::now();
+    let res = $e();
+    let dur = start.elapsed();
+    (res, dur)
+  }};
+}
+
+fn keygen_save_large() {
+  const BUFFER_SIZE: usize = 64 * 1024;
+
+  let path = get_key_file_path(MAX_NUM_GENS);
+
+  if check_sanity_of_ptau_file::<bn256::G1Affine>(&path, MAX_NUM_GENS + 1, 1).is_err() {
+    println!("Generating {} KZG keys ", MAX_NUM_GENS);
+
+    let (ck, dur) = timeit!(|| { CommitmentKey::<E>::setup_from_rng(LABEL, MAX_NUM_GENS, OsRng) });
+
+    println!("Generated {} keys in {:?}", MAX_NUM_GENS, dur);
+
+    let file = OpenOptions::new()
+      .write(true)
+      .create(true)
+      .truncate(true)
+      .open(&path)
+      .unwrap();
+    let mut writer = BufWriter::with_capacity(BUFFER_SIZE, &file);
+
+    let (_, dur) = timeit!(|| {
+      ck.save_to(&mut writer).unwrap();
+    });
+
+    println!(
+      "Saved {} keys to {} in {:?}, file size={}MB",
+      MAX_NUM_GENS,
+      &path,
+      dur,
+      file.metadata().unwrap().len() / 1024 / 1024
+    );
+  } else {
+    println!("Key file already exists at {}", &path);
+  }
+
+  let (res, dur) = timeit!(|| {
+    let file = OpenOptions::new().read(true).open(&path).unwrap();
+    let mut reader = BufReader::new(file);
+    CommitmentEngine::<E>::load_setup(&mut reader, MAX_NUM_GENS)
+  });
+
+  assert!(res.is_ok());
+
+  println!("Loaded {} keys from {} in {:?}", MAX_NUM_GENS, &path, dur);
+}
+
+fn main() {
+  keygen_save_large();
+}