fix: Patch circuits' asserts (#26)

.github/actions/compile-witness-generator/action.yml

@@ -83,6 +83,7 @@ runs:
         cp "${SOURCES_ROOT}/circom_adapter.hpp" "${CIRCUIT_CPP_PATH}/circom_adapter.hpp"
         cp "${SOURCES_ROOT}/circom_fwd.hpp" "${CIRCUIT_CPP_PATH}/circom_fwd.hpp"
         cp "${SOURCES_ROOT}/types.hpp" "${CIRCUIT_CPP_PATH}/types.hpp"
+        cp "${SOURCES_ROOT}/assert.h" "${CIRCUIT_CPP_PATH}/assert.h"
 
     # TODO: Instead of replace, make a fork that generates the appropriate Makefile
     - name: Replace ${{ inputs.circuit-name-display }}'s Makefile

justfile

@@ -35,7 +35,7 @@ poq: check-circom
     # circom-generated main() has no return on the success path; patch it before -O3 turns it into an infinite loop
     {{sed_i}} ':a;N;$!ba;s/\n}\n\n*$/\n  return 0;\n}/' blend/poq_cpp/main.cpp
     cp -r {{src}}/poq blend/poq_cpp/poq
-    cp {{src}}/circom_adapter.cpp {{src}}/circom_adapter.hpp {{src}}/circom_fwd.hpp {{src}}/types.hpp blend/poq_cpp/
+    cp {{src}}/circom_adapter.cpp {{src}}/circom_adapter.hpp {{src}}/circom_fwd.hpp {{src}}/types.hpp {{src}}/assert.h blend/poq_cpp/
     cp {{ci_makefile}} blend/poq_cpp/Makefile
     cp blend/test_ffi.cpp blend/poq_cpp/test_ffi.cpp
     make -C blend/poq_cpp PROJECT=poq linux-lib
@@ -51,7 +51,7 @@ pol: check-circom
     # circom-generated main() has no return on the success path; patch it before -O3 turns it into an infinite loop
     {{sed_i}} ':a;N;$!ba;s/\n}\n\n*$/\n  return 0;\n}/' mantle/pol_cpp/main.cpp
     cp -r {{src}}/pol mantle/pol_cpp/pol
-    cp {{src}}/circom_adapter.cpp {{src}}/circom_adapter.hpp {{src}}/circom_fwd.hpp {{src}}/types.hpp mantle/pol_cpp/
+    cp {{src}}/circom_adapter.cpp {{src}}/circom_adapter.hpp {{src}}/circom_fwd.hpp {{src}}/types.hpp {{src}}/assert.h mantle/pol_cpp/
     cp {{ci_makefile}} mantle/pol_cpp/Makefile
     cp mantle/test_pol.cpp mantle/pol_cpp/test_pol.cpp
     make -C mantle/pol_cpp PROJECT=pol linux-lib
@@ -67,7 +67,7 @@ poc: check-circom
     # circom-generated main() has no return on the success path; patch it before -O3 turns it into an infinite loop
     {{sed_i}} ':a;N;$!ba;s/\n}\n\n*$/\n  return 0;\n}/' mantle/poc_cpp/main.cpp
     cp -r {{src}}/poc mantle/poc_cpp/poc
-    cp {{src}}/circom_adapter.cpp {{src}}/circom_adapter.hpp {{src}}/circom_fwd.hpp {{src}}/types.hpp mantle/poc_cpp/
+    cp {{src}}/circom_adapter.cpp {{src}}/circom_adapter.hpp {{src}}/circom_fwd.hpp {{src}}/types.hpp {{src}}/assert.h mantle/poc_cpp/
     cp {{ci_makefile}} mantle/poc_cpp/Makefile
     cp mantle/test_poc.cpp mantle/poc_cpp/test_poc.cpp
     make -C mantle/poc_cpp PROJECT=poc linux-lib
@@ -83,7 +83,7 @@ signature: check-circom
     # circom-generated main() has no return on the success path; patch it before -O3 turns it into an infinite loop
     {{sed_i}} ':a;N;$!ba;s/\n}\n\n*$/\n  return 0;\n}/' mantle/signature_cpp/main.cpp
     cp -r {{src}}/signature mantle/signature_cpp/signature
-    cp {{src}}/circom_adapter.cpp {{src}}/circom_adapter.hpp {{src}}/circom_fwd.hpp {{src}}/types.hpp mantle/signature_cpp/
+    cp {{src}}/circom_adapter.cpp {{src}}/circom_adapter.hpp {{src}}/circom_fwd.hpp {{src}}/types.hpp {{src}}/assert.h mantle/signature_cpp/
     cp {{ci_makefile}} mantle/signature_cpp/Makefile
     cp mantle/test_signature.cpp mantle/signature_cpp/test_signature.cpp
     make -C mantle/signature_cpp PROJECT=signature linux-lib

rust/logos-blockchain-circuits-poc-sys/src/native.rs

@@ -60,6 +60,29 @@ mod tests {
     static INPUTS: LazyLock<PathBuf> =
         LazyLock::new(|| PathBuf::from(env!("CARGO_MANIFEST_DIR")).join("sample.input.json"));
 
+    #[test]
+    fn test_generate_witness_invalid_json_returns_err() {
+        let input = PocWitnessInput::new("{".to_owned()).unwrap();
+        assert!(generate_witness(&input).is_err());
+    }
+
+    #[test]
+    fn test_generate_witness_missing_inputs_returns_err() {
+        let input = PocWitnessInput::new("{}".to_owned()).unwrap();
+        assert!(generate_witness(&input).is_err());
+    }
+
+    #[test]
+    fn test_generate_witness_constraint_violation_returns_err() {
+        let json = std::fs::read_to_string(&*INPUTS).unwrap();
+        let bad_json = json.replace(
+            "\"voucher_root\": \"20810875415353676096192834577269613981524168537821543897016159330974871397924\"",
+            "\"voucher_root\": \"1\"",
+        );
+        let input = PocWitnessInput::new(bad_json).unwrap();
+        assert!(generate_witness(&input).is_err());
+    }
+
     #[test]
     fn test_generate_witness() {
         let dat = LIB_DIR.join("witness_generator");

rust/logos-blockchain-circuits-pol-sys/src/native.rs

@@ -60,6 +60,29 @@ mod tests {
     static INPUTS: LazyLock<PathBuf> =
         LazyLock::new(|| PathBuf::from(env!("CARGO_MANIFEST_DIR")).join("sample.input.json"));
 
+    #[test]
+    fn test_generate_witness_invalid_json_returns_err() {
+        let input = PolWitnessInput::new("{".to_owned()).unwrap();
+        assert!(generate_witness(&input).is_err());
+    }
+
+    #[test]
+    fn test_generate_witness_missing_inputs_returns_err() {
+        let input = PolWitnessInput::new("{}".to_owned()).unwrap();
+        assert!(generate_witness(&input).is_err());
+    }
+
+    #[test]
+    fn test_generate_witness_constraint_violation_returns_err() {
+        let json = std::fs::read_to_string(&*INPUTS).unwrap();
+        let bad_json = json.replace(
+            "\"ledger_aged\": \"9907496234164738674719754286318998202143315407023653151112941050435603056651\"",
+            "\"ledger_aged\": \"1\"",
+        );
+        let input = PolWitnessInput::new(bad_json).unwrap();
+        assert!(generate_witness(&input).is_err());
+    }
+
     #[test]
     fn test_generate_witness() {
         let dat = LIB_DIR.join("witness_generator");

rust/logos-blockchain-circuits-poq-sys/src/native.rs

@@ -60,6 +60,31 @@ mod tests {
     static INPUTS: LazyLock<PathBuf> =
         LazyLock::new(|| PathBuf::from(env!("CARGO_MANIFEST_DIR")).join("sample.input.json"));
 
+    #[test]
+    fn test_generate_witness_invalid_json_returns_err() {
+        let input = PoqWitnessInput::new("{".to_owned()).unwrap();
+        assert!(generate_witness(&input).is_err());
+    }
+
+    #[test]
+    fn test_generate_witness_missing_inputs_returns_err() {
+        let input = PoqWitnessInput::new("{}".to_owned()).unwrap();
+        assert!(generate_witness(&input).is_err());
+    }
+
+    #[test]
+    fn test_generate_witness_constraint_violation_returns_err() {
+        let json = std::fs::read_to_string(&*INPUTS).unwrap();
+        // Swap core_root for a wrong value; the Merkle path no longer verifies,
+        // so is_registered.out = 0 and the constraint at circom line 108 fires.
+        let bad_json = json.replace(
+            "\"core_root\": \"20423847801203321296654759690878714805328777188198550442842378955293864405749\"",
+            "\"core_root\": \"1\"",
+        );
+        let input = PoqWitnessInput::new(bad_json).unwrap();
+        assert!(generate_witness(&input).is_err());
+    }
+
     #[test]
     fn test_generate_witness() {
         let dat = LIB_DIR.join("witness_generator");

rust/logos-blockchain-circuits-signature-sys/src/native.rs

@@ -65,6 +65,18 @@ mod tests {
     static INPUTS: LazyLock<PathBuf> =
         LazyLock::new(|| PathBuf::from(env!("CARGO_MANIFEST_DIR")).join("sample.input.json"));
 
+    #[test]
+    fn test_generate_witness_invalid_json_returns_err() {
+        let input = SignatureWitnessInput::new("{".to_owned()).unwrap();
+        assert!(generate_witness(&input).is_err());
+    }
+
+    #[test]
+    fn test_generate_witness_missing_inputs_returns_err() {
+        let input = SignatureWitnessInput::new("{}".to_owned()).unwrap();
+        assert!(generate_witness(&input).is_err());
+    }
+
     #[test]
     fn test_generate_witness() {
         let dat = LIB_DIR.join("witness_generator");

rust/logos-blockchain-circuits-tests/tests/conflicts.rs

@@ -22,4 +22,23 @@ mod tests {
         let poq_result = lbc_poq_sys::generate_witness(&inputs_json);
         assert!(poq_result.is_ok());
     }
+
+    #[test]
+    fn test_concurrent_poq_calls() {
+        let inputs_json_raw = std::fs::read_to_string(inputs::POQ.as_path()).unwrap();
+
+        let handles: Vec<_> = (0..4)
+            .map(|_| {
+                let json = inputs_json_raw.clone();
+                std::thread::spawn(move || {
+                    let input = PoqWitnessInput::new(json).unwrap();
+                    lbc_poq_sys::generate_witness(&input)
+                })
+            })
+            .collect();
+
+        for h in handles {
+            assert!(h.join().unwrap().is_ok());
+        }
+    }
 }

src/assert.h

@@ -0,0 +1,27 @@
+// Assert-to-throw shim for circom-generated circuit code.
+//
+// Problem
+// -------
+// Circom generates C++ code that calls the standard assert() macro to enforce
+// circuit constraints (e.g. `assert(Fr_isTrue(&expaux[0]))`). When compiled
+// into a standalone binary, a failing assert aborts the subprocess and the
+// caller receives a non-zero exit code; an error. When compiled into a static
+// library and linked into the caller's process, the same abort kills the entire
+// process. A library must never call abort() on its caller.
+//
+// Mechanism
+// ---------
+// This file is copied into each circuit's build directory as assert.h. The
+// Makefile already passes -I. so the compiler finds this file before the
+// system assert.h when the generated code does `#include <assert.h>`.
+// #include_next <assert.h> pulls in the real system header (so all
+// declarations are present), then we redefine the assert macro to throw a
+// std::runtime_error instead of calling abort(). #pragma once prevents a
+// second include from re-running and undoing the redefinition.
+#pragma once
+#include_next <assert.h>
+#undef assert
+#include <stdexcept>
+#define assert(cond) \
+    ((cond) ? void(0) : throw std::runtime_error( \
+        std::string("Circuit constraint violated in ") + __FILE__ + ":" + std::to_string(__LINE__) + ": " + #cond))

src/poc/ffi.cpp

@@ -92,7 +92,13 @@ static Status generate_witness_impl(const WitnessInput* input, Bytes* output) {
     Circom_Circuit* circuit = loadCircuit(circuit_bytes);
     Circom_CalcWit* ctx = new Circom_CalcWit(circuit);
 
-    loadJson(ctx, input->inputs_json);
+    try {
+        loadJson(ctx, input->inputs_json);
+    } catch (...) {
+        delete ctx;
+        delete circuit;
+        throw;
+    }
     if (ctx->getRemaingInputsToBeSet()!=0) {
         const std::string message = "Not all inputs have been set. Only " + std::to_string(get_main_input_signal_no()-ctx->getRemaingInputsToBeSet()) + " out of " + std::to_string(get_main_input_signal_no()) + ".";
         delete ctx;

src/pol/ffi.cpp

@@ -92,7 +92,13 @@ static Status generate_witness_impl(const WitnessInput* input, Bytes* output) {
     Circom_Circuit* circuit = loadCircuit(circuit_bytes);
     Circom_CalcWit* ctx = new Circom_CalcWit(circuit);
 
-    loadJson(ctx, input->inputs_json);
+    try {
+        loadJson(ctx, input->inputs_json);
+    } catch (...) {
+        delete ctx;
+        delete circuit;
+        throw;
+    }
     if (ctx->getRemaingInputsToBeSet()!=0) {
         const std::string message = "Not all inputs have been set. Only " + std::to_string(get_main_input_signal_no()-ctx->getRemaingInputsToBeSet()) + " out of " + std::to_string(get_main_input_signal_no()) + ".";
         delete ctx;

src/poq/ffi.cpp

@@ -92,7 +92,13 @@ static Status generate_witness_impl(const WitnessInput* input, Bytes* output) {
     Circom_Circuit* circuit = loadCircuit(circuit_bytes);
     Circom_CalcWit* ctx = new Circom_CalcWit(circuit);
 
-    loadJson(ctx, input->inputs_json);
+    try {
+        loadJson(ctx, input->inputs_json);
+    } catch (...) {
+        delete ctx;
+        delete circuit;
+        throw;
+    }
     if (ctx->getRemaingInputsToBeSet()!=0) {
         const std::string message = "Not all inputs have been set. Only " + std::to_string(get_main_input_signal_no()-ctx->getRemaingInputsToBeSet()) + " out of " + std::to_string(get_main_input_signal_no()) + ".";
         delete ctx;

src/signature/ffi.cpp

@@ -92,7 +92,13 @@ static Status generate_witness_impl(const WitnessInput* input, Bytes* output) {
     Circom_Circuit* circuit = loadCircuit(circuit_bytes);
     Circom_CalcWit* ctx = new Circom_CalcWit(circuit);
 
-    loadJson(ctx, input->inputs_json);
+    try {
+        loadJson(ctx, input->inputs_json);
+    } catch (...) {
+        delete ctx;
+        delete circuit;
+        throw;
+    }
     if (ctx->getRemaingInputsToBeSet()!=0) {
         const std::string message = "Not all inputs have been set. Only " + std::to_string(get_main_input_signal_no()-ctx->getRemaingInputsToBeSet()) + " out of " + std::to_string(get_main_input_signal_no()) + ".";
         delete ctx;