test: add fuzz tests for keccak

fuzz/Cargo.toml

@@ -31,6 +31,20 @@ test = false
 doc = false
 bench = false
 
+[[bin]]
+name = "keccak_doesnt_panic"
+path = "fuzz_targets/keccak/no_panics.rs"
+test = false
+doc = false
+bench = false
+
+[[bin]]
+name = "keccak_memory_safety"
+path = "fuzz_targets/keccak/memory_safety.rs"
+test = false
+doc = false
+bench = false
+
 [[bin]]
 name = "openzeppelin_stylus_utils"
 path = "fuzz_targets/openzeppelin_stylus_utils.rs"

fuzz/fuzz_targets/keccak/memory_safety.rs

@@ -0,0 +1,24 @@
+#![no_main]
+#[macro_use]
+extern crate libfuzzer_sys;
+extern crate openzeppelin_crypto;
+
+use crate::openzeppelin_crypto::{
+    hash::{BuildHasher, Hasher},
+    keccak::KeccakBuilder,
+};
+
+fuzz_target!(|data: &[u8]| {
+    let mut hasher = KeccakBuilder.build_hasher();
+
+    // Test memory safety by updating with different slice patterns
+    for i in 0..data.len() {
+        hasher.update(&data[..i]);
+        let mut new_hasher = KeccakBuilder.build_hasher();
+        new_hasher.update(&data[i..]);
+        let _ = new_hasher.finalize();
+    }
+
+    // Finalize the original hasher
+    let _ = hasher.finalize();
+});

fuzz/fuzz_targets/keccak/no_panics.rs

@@ -0,0 +1,15 @@
+#![no_main]
+#[macro_use]
+extern crate libfuzzer_sys;
+extern crate openzeppelin_crypto;
+
+use crate::openzeppelin_crypto::{
+    hash::{BuildHasher, Hasher},
+    keccak::KeccakBuilder,
+};
+
+fuzz_target!(|data: &[u8]| {
+    let mut hasher = KeccakBuilder.build_hasher();
+    hasher.update(data);
+    _ = hasher.finalize();
+});