By utilizing Cloudflare's circl library, the Open Quantum Safe (liboqs) C-FFI engine, Katzenpost's hpqc (Hybrid Post-Quantum Cryptography) engine, and EPFL's kyber abstract algebra engine, PQPG implements the latest FIPS 203, 204, and 205 post-quantum standards alongside an exhaustive, mathematically absolute composite hybrid architecture. It guarantees absolute data confidentiality and metadata anonymity against both traditional and quantum adversaries.

PQPG operates as an Asynchronous Secure Messenger (Double Ratchet), a One-Shot Stateless Messenger, a Personal Post-Quantum Vault, a Trustless Distributed Vault (Feldman VSS), a Zero-Knowledge Time-Lock Engine, a Zero-Knowledge Data Notary (Proof of Breach), and an Interoperable OpenPGP Node, allowing users to wrap local files, directories, and networks inside an impenetrable quantum-resistant armor.

• The 120-Suite Universal Hybrid Engines: Enforces a strict, 100% Hybrid-Only rule across distinct cryptographic profiles. By seamlessly bridging Cloudflare's lattice logic (circl), Katzenpost's code-based logic (hpqc), and the hardware-accelerated liboqs C-FFI pipeline with classical ECC (X25519/X448/Ed25519/Ed448), PQPG guarantees that even if a devastating quantum cryptanalytic breakthrough occurs, your payloads cannot fall below classical baseline security.
• Operational OQS Integration (MPC & Multivariate): Natively binds experimental liboqs algorithms—such as MPC-in-the-head (MQOM, CROSS) and Multivariate Quadratics (MAYO, OV, SNOVA)—into pure Go architectures via strict CGO memory isolation and SHA3-512 dynamic combiners.
• Cross-Library Paranoia Composites: Dynamically combines entirely different mathematical hardness assumptions from entirely different software libraries. Seamlessly pair a native CGO McEliece-8192 KEM (Code-Based) alongside a Cloudflare Dilithium5 DSA (Lattice-Based) and lock it using a Skein-1024 Wide-Block Cipher.
• Stateless Encrypted Payloads: Enables secure, one-shot messaging outside of an active Double Ratchet session. Utilizes direct KEM encapsulation passing through a 64-byte SHA3-512 Cryptographic Combiner to dynamically derive maximum-entropy keys for massive symmetric ciphers.
• Detached Signatures (Stateless & Stateful): Hash massive payloads natively from the hard drive to generate tiny, mathematically isolated .pqc_sig files (using advanced lattice, code-based, or multivariate combinations) or ultra-secure .lms_sig files for failsafe release engineering.
• Unified Wide-Block Architecture (Pure Skein): Integrates the massive Threefish tweakable block cipher (up to 1024-bit block sizes) with the Skein hash function. This creates an ultra-conservative, unified cryptographic core immune to Grover's algorithm and future classical cryptanalysis, utilizing native Encrypt-then-MAC (EtM) processing for enormous payloads.
• Misuse-Resistant & Extended-Nonce AEADs: The Ratchet, Stateless, and Vault architectures natively integrate CAESAR-winning Deoxys-II, RFC 8452 AES-GCM-SIV, and extended 24-byte nonce stream ciphers (XChaCha20, XAES-GCM). This mathematically eliminates the risk of nonce-reuse attacks, state-desynchronization leakage, and birthday-bound collisions on massive payloads.
• Isolated OpenPGP v6 Compatibility Engine: Natively implements draft-ietf-openpgp-pqc utilizing strict composite algorithms (e.g., Kyber768 + X25519, ML-DSA-65 + Ed25519). Features a completely air-gapped architectural compartment to ensure standard Web of Trust interoperability without polluting the bespoke Double Ratchet ecosystem.
• Stateful Post-Quantum Root Identities (LMS/XMSS): Fully supports FIPS 205 Hash-Based Signatures for highly secure, failsafe software release engineering, powered natively by a statically linked Open Quantum Safe (liboqs) C library.
• Zero-Knowledge Data Notary (Proof of Breach): Proves possession of massive datasets (e.g., leaked or compromised data) without revealing a single byte of the file itself. Employs a native Groth16 zk-SNARK over the BN254 elliptic curve using a custom MiMC Merkle Tree pipeline.
• Zero-Knowledge Time-Lock Puzzles (VDF): Encapsulates files inside an RSA-4096 Hidden Order Group. Uses a native Fiat-Shamir Zero-Knowledge Proof (Sigma Protocol) to mathematically guarantee puzzle validity, forcing sequential CPU delays (Dead Man's Switch) without exposing solvers to forged puzzles.
• Trustless Distributed Vaults: Implements Feldman’s Verifiable Secret Sharing (VSS) over the Ed25519 scalar field. Generates M-of-N Shamir shares bound to ECC commitments, mathematically proving share validity and preventing malicious dealers from destroying vaults.
• Cryptographic Memory Hygiene & Rainbow Table Immunity: Secures local keyrings using dynamic Argon2id salt rotation to neutralize pre-computed Rainbow Tables. Guarantees that all highly sensitive private key byte-slices (and C-FFI allocated buffers) are explicitly shredded from RAM immediately after cryptographic operations conclude.
• Perfect Forward Secrecy (PFS): Implements a Post-Quantum Double Ratchet. The state machine seamlessly handles out-of-order packets, dropping "dangling" keys after a strict 1000-message boundary to prevent RAM/State Exhaustion attacks.

PQPG manages Perfect Forward Secrecy and Post-Compromise Security using a highly robust "Separation of Concerns" architecture. The engine is divided into three distinct layers to prevent database corruption during asynchronous transfers:

1. The Brain (double_ratchet.go): A strictly stateless, functional mathematical engine. It knows nothing about the network or databases; it simply ingests byte arrays, executes Keccak KDF sponge derivations (now securely outputting 512-bit pure entropy for massive symmetric ciphers), and outputs new cryptographic chain keys.
2. The Memory (session.go / BoltDB): The ACID-compliant, encrypted storage vault. It safely stores the RatchetState, tracks historical public keys to defeat the Implicit Rejection (FO Transform) Trap, and runs the HMAC-SHA3 Anti-Replay Cache.
3. The Conductor (stream.go): The orchestrator layer. It pulls state from BoltDB, asks the Brain to spin the Ratchets in RAM, and utilizes Deferred Commits. The database state is only updated and saved to the hard drive if the AEAD cryptographic signature perfectly authenticates the payload, rendering PQPG virtually immune to session corruption from malformed files.

The codebase strictly adheres to SOLID principles, utilizing Adapter Patterns and dynamic Factory Registries to isolate cryptographic mathematics from network framing, anti-replay state validation, and identity management.

pqc-messenger/
├── cmd/
│ └── messenger/
│ ├── main.go # Top-level Subsystem Routing (Core, OQS, OpenPGP)
│ ├── archive.go # On-the-fly Directory Tarball & Compression Engine
│ ├── notary-handlers.go # CLI orchestration for ZK Data Notary (Prove/Verify)
│ ├── openpgp-handlers.go # CLI orchestration for the isolated OpenPGP v6 compartment
│ ├── identity-handlers.go # Orchestrates the Core HPQC Hybrid UI Selection
│ ├── oqs-handlers.go # Orchestrates the liboqs 120-suite Hybrid UI Selection
│ └── *-handlers.go
├── internal/
│ ├── crypto/
│ │ ├── registry.go # Dynamic Namespace Router (Hpqc-, Oqs-, Hybrid-)
│ │ ├── hybrid-kem.go # PQPG SHA3-512 KEM Cryptographic Combiner
│ │ ├── hybrid-dsa.go # PQPG Independent Proof DSA Combiner
│ │ ├── hpqc-adapter.go # Abstract Interface Adapter for Katzenpost HPQC
│ │ ├── oqs-adapter.go # Safe C-FFI Interface Adapter & Memory Manager for liboqs
│ │ └── double-ratchet.go # Stateless KDF math for the PFS Ratchet
│ ├── hpqc/ # Native Katzenpost engine (Code-based/NTRU Lattices)
│ ├── hpq/ # Scorched-Earth localized HPQ dependency
│ ├── xx-network-crypto/ # Scorched-Earth localized upstream dependency
│ ├── xx-network-primitives/ # Scorched-Earth localized upstream dependency
│ ├── elixxir-crypto/ # Scorched-Earth localized upstream dependency
│ ├── deoxysii/ # CAESAR-Winning Misuse-Resistant AEAD (MRAE)
│ ├── aesgcmsiv-noasm/ # RFC 8452 AES-GCM-SIV (Pure Go / Cross-Platform)
│ ├── aesgcmsiv-asm/ # AES-SIV-CMAC (Deterministic Hardware Accelerated)
│ ├── threefish/ # Tweakable Wide-Block Cipher Engine (256/512/1024)
│ ├── skein/ # UBI Chaining Mode Hashing & XOF Engine
│ ├── blake3/ # Native BLAKE3 Implementation
│ ├── oqs/ # Hardcoded Open Quantum Safe C-FFI Wrappers
│ ├── openpgp_pqc/ # draft-ietf-openpgp-pqc wrappers for ProtonMail/gopenpgp v3
│ ├── identity/
│ │ ├── keyring.go # PKI management and disk I/O
│ │ ├── rollback.go # Hardware-safe atomic AES-GCM Canary state guard
│ │ └── session.go # AES-GCM Encrypted BoltDB (Blind Indexes & Anti-Replay)
│ ├── vdf/
│ │ └── rsa_vdf.go # Native RSA Subgroup math & Fiat-Shamir ZKP
│ ├── zkp/
│ │ └── engine.go # Groth16 Setup, Prove, and Verify mathematical interface
│ └── packet/
│ ├── stream.go # Double Ratchet Sealed Sender Envelopes (Chunked)
│ └── stateless.go # One-Shot Payloads & Massive Entropy KEM Extraction
├── go.mod
└── go.sum

• Go 1.25.10 or higher.
• CMake, Ninja, and a C Compiler (gcc/clang) for building the static OQS subsystem.
• Active internet connection to fetch Cloudflare circl, EPFL kyber/v4, ConsenSys gnark, and ProtonMail gopenpgp.
• (Note: hpqc and its upstream dependencies are hard-forked and strictly localized in the internal/ directory to permanently protect against upstream GitLab/GitHub repository deletions and dependency poisoning).

To utilize FIPS 205 Stateful Signatures and experimental OQS KEMs without trapping users in shared-library (.so) dependency hell, PQPG explicitly requires compiling liboqs as a static archive (.a) with OpenSSL disabled. This guarantees maximum cross-platform binary portability.

cd pqpg
# Clone the upstream Open Quantum Safe repository
git clone -b main https://github.com/open-quantum-safe/liboqs.git
cd liboqs
# Prepare the build directory
mkdir build && cd build
# Configure CMake for a Static Archive WITHOUT OpenSSL
cmake -G Ninja \
 -DCMAKE_INSTALL_PREFIX=$(pwd)/../oqs_static_env \
 -DBUILD_SHARED_LIBS=OFF \
 -DOQS_USE_OPENSSL=OFF \
 -DOQS_ENABLE_SIG_STFL_LMS=ON \
 -DOQS_ENABLE_SIG_STFL_XMSS=ON \
 -DOQS_HAZARDOUS_EXPERIMENTAL_ENABLE_SIG_STFL_KEY_SIG_GEN=ON \
 ..
# Compile and output the static archive to the isolated environment folder
ninja
ninja install
cd ../..

Once the oqs_static_env is successfully built, go to the internal/oqs and change the cgo LDFLAGS and cgo CFLAGS to the corresponding liboqs.a library path inside cfuncs.go and oqs.go.

Launch the interactive engine by running ./pqpg in your terminal. You will be prompted to select one of three routing modules:

• Option 1: Core Crypto Engine: The native, pure-Go/Assembly ecosystem containing the advanced Zero-Knowledge interfaces (Multi-platform).
• Option 2: OQS Extension Engine: The hardware-accelerated liboqs C-FFI pipeline exclusively driving messaging, vaults, and detached signatures (Restricted to Linux/AMD64).
• Option 3: OpenPGP PQC Engine: The interoperable draft-ietf-openpgp-pqc v6 compatibility node.

Depending on whether you boot into the Core Engine or the OQS Extension Engine, PQPG routes you through the unified network layers.

Generate a cryptographic profile. The Core Engine offers a 120-suite selection built on CIRCL and HPQC logic, while the OQS Engine unlocks an exclusive 120-suite hardware-accelerated profiler featuring experimental algorithms like MAYO, OV, SNOVA, MQOM2, and CROSS.

Securely send a payload using the Perfect Forward Secrecy protocol. You can target either a single file or an entire directory (which is automatically bundled into a maximum-compression .tar.gz archive on the fly before encryption).

Encrypt data for a recipient outside of an active Ratchet session. Using the stateless.go architecture, the engine executes direct KEM encapsulation and derives the payload key via a strict 64-byte SHA3-512 KDF, ensuring maximum entropy for wide-block ciphers.

Wrap a local file or directory inside a continuous stream-encrypted envelope deterministically bound to your own identity for secure cold storage.

Hash a massive file natively from the hard drive to generate a tiny, mathematically isolated .pqc_sig file using advanced lattice, code-based, or multivariate quadratic signature combinations.

Generate an ultra-secure .lms_sig or .xmss_sig file specifically designed for software release engineering. The engine synchronously locks the OS, executes the hash-tree traversal, advances the hardware-safe Anti-Rollback AES-GCM canary, and outputs the signature.

The following computational features rely on the gnark and kyber abstract algebra engines and are accessible strictly through the Option 1: Core Crypto Engine menu.

Distribute a vault across multiple stakeholders. The engine plots a secret polynomial over the Ed25519 scalar field and outputs N shares. Upon restoration, the engine mathematically proves share authenticity before executing Lagrange interpolation to restore the data.

Lock a file or directory inside an RSA-4096 Verifiable Delay Function (VDF). The engine generates a sequential CPU puzzle and a native Fiat-Shamir Zero-Knowledge Proof, outputting a .timelock artifact. Unlocking a puzzle forces un-parallelizable sequential CPU operations to derive the AES decryption key.

Act as a Prover and generate a zk-SNARK proving possession of a targeted leak file or database. The engine processes the local file chunk-by-chunk inside a field-compliant MiMC Merkle tree and exports a standalone .zkp proof envelope. Auditors can verify the proof by checking the R1CS constraints against a SHA3-256 Verifying Key fingerprint.

Cloudflare CIRCL The core lattice and ECC mathematics of PQPG are powered by CIRCL (Cloudflare Interoperable, Reusable Cryptographic Library), an advanced open-source engine bringing state-of-the-art post-quantum primitives to Go.

Katzenpost HPQC This library contains highly optimized, native CGO/Assembly Golang implementations of leading quantum-resistant Code-based primitives (McEliece, HQC) and NTRU lattices (SNTRUP). Available at: https://github.com/katzenpost/hpqc

Open Quantum Safe (liboqs) The C-FFI pipeline providing hardware-accelerated Stateful Hash-Based Signatures (LMS/XMSS) and experimental MPC-in-the-head/Multivariate algorithms by statically linking liboqs, the premier C library for prototyping quantum-resistant cryptography.

EPFL Advanced Cryptography Group (Kyber) Threshold cryptography and Feldman VSS operations rely on the go.dedis.ch/kyber abstract algebra suite, providing the vital Elliptic Curve scalar math required for Zero-Knowledge and verifiable group commitments.

ConsenSys gnark The zero-knowledge SNARK ecosystem, circuit compilation, and R1CS Groth16 proving/verifying mechanisms are powered entirely by the high-performance gnark framework.

Oasis Protocol & Deoxys-II The CAESAR competition-winning Deoxys-II algorithm is powered by the highly audited implementations developed for the Oasis network core, bringing Misuse-Resistant Authenticated Encryption (MRAE) to PQPG.

MinIO (secure-io) & Fernandezvara AES-SIV-CMAC and RFC 8452 AES-GCM-SIV implementations utilize the high-performance logic provided by the MinIO cryptography team and the fernandezvara BoringSSL Go ports.

Skein & Threefish The wide-block cryptographic primitives are based on the Skein hash function family designed by Bruce Schneier, Niels Ferguson, Stefan Lucks, Doug Whiting, Mihir Bellare, Tadayoshi Kohno, Jon Callas, and Jesse Walker. Implemented via Go adaptations.

ProtonMail (gopenpgp & go-crypto) The OpenPGP compatibility compartment is powered by ProtonMail's highly audited gopenpgp (v3) library and their fork of the Go crypto library, providing strict compliance with the draft-ietf-openpgp-pqc specifications.

Multiple packages from github.com/aead developed by Andreas Auernhammer The Serpent block cipher, Ascon, and related high-performance symmetric packages.

go-xmssmt (by bwesterb) Go implementation of the stateful hash-based signature-scheme XMSS(MT) described in RFC 8391 (XMSS: Extended Hash-Based Signatures) and NIST SP 800-208.

lms-go (by Trail of Bits) Go implementation of Leighton-Micali stateful Hash-Based Signatures (RFC 8554).

Elixxir & xx network Primitives and cryptography libraries (git.xx.network) providing upstream dependency support for HPQC sub-modules.

CIRCL License This software relies on the Cloudflare CIRCL library which is released under the BSD-3 Clause License. Faz-Hernandez, A. and Kwiatkowski, K. (2019). Introducing CIRCL: An Advanced Cryptographic Library. Cloudflare. Available at https://github.com/cloudflare/circl. v1.6.3 Accessed May, 2026.

Copyright (c) 2019, Cloudflare Inc. All rights reserved. Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:

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2. Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.
3. Neither the name of the copyright holder nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission.