Add compute_cells fuzzing support

fuzz/Cargo.toml

@@ -61,6 +61,12 @@ path = "fuzz_targets/fuzz_verify_blob_kzg_proof_batch.rs"
 test = false
 doc = false
 
+[[bin]]
+name = "fuzz_compute_cells"
+path = "fuzz_targets/fuzz_compute_cells.rs"
+test = false
+doc = false
+
 [[bin]]
 name = "fuzz_compute_cells_and_kzg_proofs"
 path = "fuzz_targets/fuzz_compute_cells_and_kzg_proofs.rs"

fuzz/README.md

@@ -58,6 +58,7 @@ List available targets like this:
 $ cargo fuzz list
 fuzz_blob_to_kzg_commitment
 fuzz_compute_blob_kzg_proof
+fuzz_compute_cells
 fuzz_compute_cells_and_kzg_proofs
 fuzz_compute_kzg_proof
 fuzz_recover_cells_and_kzg_proofs

fuzz/fuzz_targets/fuzz_compute_cells.rs

@@ -0,0 +1,46 @@
+// Run with the following command:
+// cargo fuzz run fuzz_compute_cells_and_kzg_proofs
+
+#![no_main]
+extern crate core;
+
+use c_kzg::Blob;
+use c_kzg::KzgSettings;
+use lazy_static::lazy_static;
+use libfuzzer_sys::fuzz_target;
+use rust_eth_kzg::DASContext;
+use std::path::PathBuf;
+
+lazy_static! {
+    static ref KZG_SETTINGS: KzgSettings = {
+        let root_dir = PathBuf::from(std::env::var("CARGO_MANIFEST_DIR").unwrap());
+        let trusted_setup_file = root_dir.join("..").join("src").join("trusted_setup.txt");
+        KzgSettings::load_trusted_setup_file(&trusted_setup_file, 8).unwrap()
+    };
+    static ref DAS_CONTEXT: DASContext = DASContext::default();
+}
+
+fuzz_target!(|blob: Blob| {
+    let ckzg_result = KZG_SETTINGS.compute_cells(&blob);
+    let rkzg_result = DAS_CONTEXT.compute_cells(&blob.into_inner());
+
+    match (&ckzg_result, &rkzg_result) {
+        (Ok(ckzg_cells), Ok(rkzg_cells)) => {
+            // Ensure the results are the same.
+            for (ckzg_cell, rkzg_cell) in ckzg_cells.iter().zip(rkzg_cells.iter()) {
+                assert_eq!(ckzg_cell.to_bytes().as_slice(), rkzg_cell.as_slice())
+            }
+        }
+        (Err(_), Err(_)) => {
+            // Cannot compare errors, they are unique.
+        }
+        _ => {
+            // There is a disagreement.
+            panic!(
+                "mismatch {:?} and {:?}",
+                &ckzg_result.is_ok(),
+                &rkzg_result.is_ok()
+            );
+        }
+    }
+});

fuzz/fuzz_targets/fuzz_recover_cells_and_kzg_proofs.rs

@@ -35,7 +35,7 @@ fuzz_target!(|input: Input| {
 
     let ckzg_result = KZG_SETTINGS
         .recover_cells_and_kzg_proofs(input.cell_indices.as_slice(), input.cells.as_slice());
-    let rkzg_result = DAS_CONTEXT.recover_cells_and_proofs(input.cell_indices, cells_bytes);
+    let rkzg_result = DAS_CONTEXT.recover_cells_and_kzg_proofs(input.cell_indices, cells_bytes);
 
     match (&ckzg_result, &rkzg_result) {
         (Ok((ckzg_cells, ckzg_proofs)), Ok((rkzg_cells, rkzg_proofs))) => {