monolithic_build_multilevel

Monolithic Multi-Level Build (C Backend)

This directory contains a minimal example for building all three ML-DSA security levels in a single compilation unit, with shared code deduplicated.

Use Case

Use this approach when:

• You need all ML-DSA security levels in one application
• You want the simplest possible multi-level integration (one .c file)
• You're using only C (no native backend)

Components

An application using mldsa-native as a monolithic multi-level build needs:

1. Source tree mldsa_native/*, including top-level compilation unit mldsa_native.c (gathering all C sources) and the mldsa-native API mldsa_native.h.
2. Manually provided wrapper file mldsa_native_all.c, including mldsa_native.c three times.
3. Manually provided header file mldsa_native_all.h, including mldsa_native.h three times)
4. A secure random number generator implementing randombytes.h
5. Your application source code

Configuration

The configuration file mldsa_native_config.h sets:

• MLD_CONFIG_MULTILEVEL_BUILD: Enables multi-level mode
• MLD_CONFIG_NAMESPACE_PREFIX=mldsa: Base prefix
• MLD_CONFIG_INTERNAL_API_QUALIFIER=static: Makes internal functions static

The wrapper mldsa_native_all.c includes mldsa_native.c three times:

#define MLD_CONFIG_FILE "multilevel_config.h"

/* Include level-independent code with first level */
#define MLD_CONFIG_MULTILEVEL_WITH_SHARED
#define MLD_CONFIG_MONOBUILD_KEEP_SHARED_HEADERS
#define MLD_CONFIG_PARAMETER_SET 44
#include "mldsa_native.c"
#undef MLD_CONFIG_PARAMETER_SET
#undef MLD_CONFIG_MULTILEVEL_WITH_SHARED

/* Exclude level-independent code for subsequent levels */
#define MLD_CONFIG_MULTILEVEL_NO_SHARED
#define MLD_CONFIG_PARAMETER_SET 65
#include "mldsa_native.c"
#undef MLD_CONFIG_PARAMETER_SET
#undef MLD_CONFIG_MONOBUILD_KEEP_SHARED_HEADERS

#define MLD_CONFIG_PARAMETER_SET 87
#include "mldsa_native.c"
#undef MLD_CONFIG_PARAMETER_SET

The header mldsa_native_all.h exposes all APIs:

#define MLD_CONFIG_PARAMETER_SET 44
#include <mldsa_native.h>
#undef MLD_CONFIG_PARAMETER_SET
#undef MLD_H

#define MLD_CONFIG_PARAMETER_SET 65
#include <mldsa_native.h>
#undef MLD_CONFIG_PARAMETER_SET
#undef MLD_H

#define MLD_CONFIG_PARAMETER_SET 87
#include <mldsa_native.h>
#undef MLD_CONFIG_PARAMETER_SET
#undef MLD_H

Notes

• MLD_CONFIG_MULTILEVEL_WITH_SHARED must be set for exactly ONE level
• MLD_CONFIG_MONOBUILD_KEEP_SHARED_HEADERS prevents cleanup of shared headers between inclusions

Usage

make build   # Build the example
make run     # Run the example

Warning

The randombytes() implementation in test_only_rng/ is for TESTING ONLY. You MUST provide a cryptographically secure RNG for production use.