add target for script

Makefile

@@ -1,6 +1,6 @@
 CXX      =  clang++
 CC       =  clang
-SOURCES :=  targets/psbt.cpp targets/bech32.cpp targets/tx_des.cpp targets/miniscript_string.cpp targets/block_des.cpp targets/prefilledtransaction.cpp
+SOURCES :=  targets/script.cpp targets/psbt.cpp targets/bech32.cpp targets/tx_des.cpp targets/miniscript_string.cpp targets/block_des.cpp targets/prefilledtransaction.cpp
 INCLUDES =  dependencies/ dependencies/bitcoin/src/ dependencies/bitcoin/src/secp256k1/include
 LIB_DIR  =  dependencies/bitcoin/src/ dependencies/bitcoin/src/.libs dependencies/bitcoin/src/secp256k1/.libs rust_bitcoin_lib/target/debug btcd_lib
 OBJS    :=  $(patsubst %.cpp, build/%.o, $(SOURCES))

fuzzer.cpp

@@ -12,6 +12,7 @@
 #include "targets/tx_des.h"
 #include "targets/bech32.h"
 #include "targets/psbt.h"
+#include "targets/script.h"
 
 extern "C" int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
     FuzzedDataProvider provider(data, size);
@@ -31,6 +32,8 @@ extern "C" int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
         Bech32(provider);
     } else if (target == "psbt") {
         Psbt(provider);
+    } else if (target == "script") {
+        Script(provider);
     }
 
     return 0; // Values other than 0 and -1 are reserved for future use.

rust_bitcoin_lib/rust_bitcoin_lib.h

@@ -1,6 +1,7 @@
 #include <string>
 
 extern bool rust_miniscript_from_str(const char* miniscript_str);
+extern bool rust_bitcoin_script(const char* miniscript_str);
 extern char* rust_bitcoin_psbt(const char* miniscript_str);
 extern char* rust_miniscript_from_str_check_key(const char* miniscript_str);
 extern char* rust_bitcoin_des_block(const uint8_t *data, size_t len);

rust_bitcoin_lib/src/lib.rs

@@ -7,6 +7,7 @@ use std::str::Utf8Error;
 
 use bitcoin::bip152::PrefilledTransaction;
 use bitcoin::consensus::deserialize_partial;
+use bitcoin::consensus::encode;
 use bitcoin::Block;
 use miniscript::bitcoin::script;
 use miniscript::bitcoin::secp256k1::XOnlyPublicKey;
@@ -100,6 +101,23 @@ pub unsafe extern "C" fn rust_bitcoin_psbt(data: *const u8, len: usize) -> *mut
     }
 }
 
+#[no_mangle]
+pub unsafe extern "C" fn rust_bitcoin_script(data: *const u8, len: usize) -> bool {
+    // Safety: Ensure that the data pointer is valid for the given length
+    let data_slice = slice::from_raw_parts(data, len);
+
+    let script: Result<(bitcoin::script::ScriptBuf, usize), encode::Error> = encode::deserialize_partial(data_slice);
+    match script {
+        Err(_) => false,
+        Ok(s) => {
+            if s.0.is_op_return() || s.0.len() > 10_000 { 
+                return false
+            }
+            true
+        }
+    }
+}
+
 #[no_mangle]
 pub unsafe extern "C" fn rust_miniscript_from_str_check_key(input: *const c_char) -> *mut c_char {
     let Ok(desc) = c_str_to_str(input) else {

targets/script.cpp

@@ -0,0 +1,31 @@
+#include <fuzzer/FuzzedDataProvider.h>
+#include <iostream>
+#include <stdio.h>
+
+#include "script.h"
+#include "bitcoin/src/streams.h"
+#include "bitcoin/src/script/script.h"
+
+extern "C" bool rust_bitcoin_script(uint8_t *data, size_t len);
+
+bool CoreScript(Span<const uint8_t> buffer)
+{
+    DataStream ds{buffer};
+    CScript script;
+    try {
+        ds >> script;
+    } catch (const std::ios_base::failure& e) {
+        return false;
+    }
+    if (script.IsUnspendable()) return false;
+    return true;
+}
+
+
+void Script(FuzzedDataProvider& provider)
+{
+    std::vector<uint8_t> buffer{provider.ConsumeRemainingBytes<uint8_t>()};
+    bool core{CoreScript(buffer)};
+    bool rust_bitcoin{rust_bitcoin_script(buffer.data(), buffer.size())};
+    assert(core == rust_bitcoin);
+}

targets/script.h

@@ -0,0 +1,7 @@
+#ifndef SCRIPT_H
+#define SCRIPT_H
+
+#include <fuzzer/FuzzedDataProvider.h>
+
+void Script(FuzzedDataProvider& provider);
+#endif