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Filename Latest commit message Latest commit date
Cristian Cezar Moisés 4874010d0e v4.1.0: source-only build, multithreaded-encryption fix, security hardening
Build from source with no vendored binaries:
- Remove prebuilt libzuptsdk.so / libpqvaptvupt.so (and a stray .pyc). The
  default build needs only a C compiler + make; it links no external library
  and installs no .so. The libzuptsdk-backed modes (Argon2id KDF, --pq-sdk,
  --pq-box) are gated behind an opt-in `make WITH_SDK=1`. The default password
  KDF is PBKDF2-SHA256 and --pq (native ML-KEM-768 + X25519) is the built-in PQ
  mode. openSUSE/RPM/deb/AUR/Homebrew/Nix recipes bumped to 4.1.0; the openSUSE
  spec now builds source-only (%files ships no .so, %build/%install WITH_SDK=0).

Fix: multithreaded encrypted archives were unextractable on the native AEAD
path. The parallel compress/decompress workers skipped the F-09 frame-preface
AAD that the serial path and the archive's AAD_PREFACE flag bind into every
block MAC, so each multithreaded block failed authentication. The workers now
bind the preface via a shared serializer; output is byte-identical across
thread counts and interoperates with single-threaded archives (also fixes
`--kdf pbkdf2 -t N` in any build).

Security hardening (crafted-archive memory safety + crypto):
- LZH raw code-length stack overflow + huff_lut OOB write
- overflow-safe bounds in parse_index and solid-mode extract (heap OOB read)
- SEQ decoder safe-zone heap overflow (litlen+matchlen reserve)
- require the per-block ENCRYPTED flag on encrypted archives (plaintext forgery)
- cap archive-supplied PBKDF2 iteration count (KDF-amplification DoS)
- non-elidable secret wipe in the SDK path; restored disk images created 0600

Docs: remove AUDIT.md / BENCHMARKS.md / ROADMAP.md; trim marketing/AI-styled
text and correct KDF/PQ facts across README, SECURITY, INSTALL, DISTRIBUTION,
THREAT_MODEL, THIRD-PARTY-NOTICES, the man page, and packaging READMEs. Wire
format v1.6 unchanged.
2026-07-07 19:45:37 -03:00
.github/workflows v4.0.0: codec 2.60.4 security release, --pq-box sealed-box mode, F-16 fix 2026-06-10 18:48:58 -03:00
completions v4.0.0: codec 2.60.4 security release, --pq-box sealed-box mode, F-16 fix 2026-06-10 18:48:58 -03:00
doc v4.1.0: source-only build, multithreaded-encryption fix, security hardening 2026-07-07 19:45:37 -03:00
gui v4.1.0: source-only build, multithreaded-encryption fix, security hardening 2026-07-07 19:45:37 -03:00
include v4.1.0: source-only build, multithreaded-encryption fix, security hardening 2026-07-07 19:45:37 -03:00
jasmin v2.2.2 2026-05-01 09:58:47 -03:00
packaging v4.1.0: source-only build, multithreaded-encryption fix, security hardening 2026-07-07 19:45:37 -03:00
sdk v4.1.0: source-only build, multithreaded-encryption fix, security hardening 2026-07-07 19:45:37 -03:00
src v4.1.0: source-only build, multithreaded-encryption fix, security hardening 2026-07-07 19:45:37 -03:00
tests docs: complete zupt → vaptvupt rename; README v4.0.0 refresh 2026-06-11 22:32:31 -03:00
vendor v4.1.0: source-only build, multithreaded-encryption fix, security hardening 2026-07-07 19:45:37 -03:00
.gitignore v4.1.0: source-only build, multithreaded-encryption fix, security hardening 2026-07-07 19:45:37 -03:00
build.bat feat: add Jasmin assembly integration for crypto acceleration 2026-03-28 23:03:04 -03:00
CHANGELOG.md v4.1.0: source-only build, multithreaded-encryption fix, security hardening 2026-07-07 19:45:37 -03:00
CMakeLists.txt feat: add Jasmin assembly integration for crypto acceleration 2026-03-28 23:03:04 -03:00
DISTRIBUTION.md v4.1.0: source-only build, multithreaded-encryption fix, security hardening 2026-07-07 19:45:37 -03:00
INSTALL.md v4.1.0: source-only build, multithreaded-encryption fix, security hardening 2026-07-07 19:45:37 -03:00
install.sh docs: complete zupt → vaptvupt rename; README v4.0.0 refresh 2026-06-11 22:32:31 -03:00
LICENSE v4.0.0: codec 2.60.4 security release, --pq-box sealed-box mode, F-16 fix 2026-06-10 18:48:58 -03:00
Makefile v4.1.0: source-only build, multithreaded-encryption fix, security hardening 2026-07-07 19:45:37 -03:00
README.md v4.1.0: source-only build, multithreaded-encryption fix, security hardening 2026-07-07 19:45:37 -03:00
SECURITY.md v4.1.0: source-only build, multithreaded-encryption fix, security hardening 2026-07-07 19:45:37 -03:00
THIRD-PARTY-NOTICES.md v4.1.0: source-only build, multithreaded-encryption fix, security hardening 2026-07-07 19:45:37 -03:00
THREAT_MODEL.md v4.1.0: source-only build, multithreaded-encryption fix, security hardening 2026-07-07 19:45:37 -03:00

VaptVupt

Backup compression with hardware-adaptive codec selection, AES-256 authenticated encryption, post-quantum key encapsulation, and full-disk backup. Pure C11, ~13,000 lines. Builds and runs on x86_64, aarch64, armhf, ppc64le, s390x, and riscv64.

License: AGPL-3.0-or-later (dual-licensed AGPL + commercial).

Renamed from "Zupt" in v3.0.0 because of a prior INPI Brasil trademark registration on the name "Zupt" for unrelated software. The .zupt archive extension and ZUPT header magic bytes are unchanged — v2.x and v3.0.0 archives remain compatible. The zupt command is preserved as a symlink to vaptvupt for one major version cycle.

What's new in 4.1.0

  • Source-only tree. The prebuilt vendored libraries libzuptsdk.so and libpqvaptvupt.so have been removed. The default make needs only a C compiler and make (plus libm/pthread) — no external crypto library — and installs no .so.
  • Native --pq is the default post-quantum mode. ML-KEM-768 + X25519 hybrid KEM, in-tree C implementation, available in the default build.
  • SDK-backed modes are optional. --pq-sdk, --pq-box, and the Argon2id KDF are only available in an upstream make WITH_SDK=1 build linked against the separately distributed libzuptsdk/libpqvaptvupt.
  • Wire/on-disk format is v1.6, unchanged. Archives created by 4.0.0 are read and written identically.

F-16 (data loss): archives created by ≤ 3.8.0 at -l 8/-l 9 whose inputs included x86/ELF/PE executables may be undecodable by any version (write-time defect in the old in-tree BCJ encoder). Re-create such archives with 4.1.0 and verify extraction before deleting source data. Details in CHANGELOG.md.

Binaries for the CLI (4.1.0) and GUI (1.3.0) are on the release page.


Features

  • Hardware-adaptive codec — auto-detects AVX2/NEON at runtime and selects the codec: VaptVupt (LZ77 + tANS + SIMD decode) on capable hardware, VaptVupt-LZHP on everything else. Override with --vv or --lzhp.
  • Post-quantum encryption--pq uses ML-KEM-768 + X25519 hybrid KEM (the approach used by Signal and iMessage), protecting against "harvest now, decrypt later" attacks. In-tree, available in the default build.
  • AES-NI acceleration — AES-256-CTR via Jasmin-verified assembly with a 4-block interleaved pipeline. AVX detection validates OSXSAVE/XCR0 (no SIGILL). Falls back to C table-based AES on unsupported hardware.
  • SHA-NI acceleration — HMAC-SHA256 (the Encrypt-then-MAC pass) and PBKDF2 use the Intel SHA-NI compression path when the CPU supports it (Intel Goldmont+/Ice Lake+, AMD Zen+), selected at runtime via CPUID. Bit-identical output; scalar C fallback elsewhere. vaptvupt version prints the acceleration set for your CPU.
  • Incremental HMAC — the per-block MAC streams its segments through an incremental HMAC-SHA256 instead of copying each block's ciphertext into a temporary buffer, removing a per-block heap allocation and full-payload copy on encrypt and decrypt with a byte-for-byte identical MAC (RFC 2104).
  • Multi-threaded — compression and decompression both parallelized. -t 0 auto-detects cores.
  • Full-disk backupvaptvupt disk backup clones disks or partitions in one command. Sparse block detection skips zero regions; all encryption modes supported; restore verifies per-block XXH64 checksums.
  • Per-block integrity — XXH64 checksum + HMAC-SHA256 per block. Wrong password rejected immediately.
  • Self-describing KDF — password archives record their key-derivation profile in the authenticated header, so an archive carries the parameters needed to open it later. Unknown profiles are refused fail-closed rather than mis-derived. Default is PBKDF2-SHA256 (600K iterations); Argon2id is available in a WITH_SDK=1 build.
  • Constant-time comparisons — every security-critical comparison (HMAC tag, archive-integrity trailer, ML-KEM-768 implicit-rejection check) routes through a single primitive (zupt_ct_memeq, branch-free, volatile accumulator, length-independent), checked by a dudect-style Welch t-test in CI.
  • Formally verified crypto — 5 Jasmin assembly functions with constant-time proofs; 19 ACSL-annotated functions for Frama-C memory safety analysis.
  • Multi-architecture — builds on x86_64, aarch64, armhf, ppc64le, s390x, riscv64. Jasmin CT crypto on x86_64, C fallback everywhere else. Any archive decompresses on any architecture.
  • No external dependencies (default build) — ML-KEM, X25519, Keccak, SHA-256, AES-256, HMAC, PBKDF2 and the VaptVupt codec are all pure C11. Builds with gcc or cl alone.

Quick Start

Build & install

git clone https://git.securityops.co/cristiancmoises/vaptvupt.git && \
cd vaptvupt && \
make && \
sudo make install

The default build needs only a C compiler and make (plus libm/pthread). make WITH_SDK=1 additionally links the separately distributed libzuptsdk/libpqvaptvupt to enable --pq-sdk, --pq-box, and the Argon2id KDF.

Pre-built packages

Assets are published on the v4.1.0 release page and verifiable against the published SHA256SUMS.txt.

Command-line tool (vaptvupt 4.1.0):

Format File Distros
Debian/Ubuntu vaptvupt_4.1.0_amd64.deb Debian 11+, Ubuntu 22.04+, Mint 21+
RPM vaptvupt-4.1.0-1.x86_64.rpm Fedora 38+, RHEL 9+, openSUSE, AlmaLinux, Rocky, other RPM-based distributions
AppDir tarball vaptvupt-4.1.0-x86_64.AppDir.tar.gz Any glibc 2.28+ (extract & run, no FUSE)
Source tarball vaptvupt-4.1.0.tar.gz Build from source on any platform
openSUSE OBS vaptvupt-4.1.0-opensuse-obs.tar.gz Open Build Service source bundle

Graphical front-end (vaptvupt-gui 1.3.0):

Format File Distros
Debian/Ubuntu vaptvupt-gui_1.3.0_all.deb Debian 11+, Ubuntu 22.04+, Mint 21+
RPM vaptvupt-gui-1.3.0-1.noarch.rpm RPM-based distributions
AppImage VaptVupt-GUI-1.3.0-x86_64.AppImage Any glibc 2.28+ (single-file, no install)
AppDir tarball VaptVupt-GUI-1.3.0-x86_64.AppDir.tar.gz Any glibc 2.28+ (extract & run)
# Verify downloads first
sha256sum -c SHA256SUMS.txt

# Debian / Ubuntu / Mint
sudo dpkg -i vaptvupt_4.1.0_amd64.deb
sudo apt-get install -f       # resolve any missing deps

# Fedora / RHEL / openSUSE / AlmaLinux / Rocky and other RPM-based distros
sudo rpm -i vaptvupt-4.1.0-1.x86_64.rpm
# or
sudo dnf install ./vaptvupt-4.1.0-1.x86_64.rpm

# AppDir tarball (no install, no FUSE required)
tar xzf vaptvupt-4.1.0-x86_64.AppDir.tar.gz
./vaptvupt-4.1.0-x86_64.AppDir/AppRun --help

# GUI AppImage (single executable)
chmod +x VaptVupt-GUI-1.3.0-x86_64.AppImage
./VaptVupt-GUI-1.3.0-x86_64.AppImage

Building from SRPM (Fedora / RHEL / RPM-based distributions)

tar xzf vaptvupt-4.1.0.srpm.tar.gz
cd ~/rpmbuild  # or use rpmbuild --define "_topdir $(pwd)"
rpmbuild -bb SPECS/vaptvupt.spec
sudo rpm -i RPMS/x86_64/vaptvupt-4.1.0-1.*.rpm

Basic usage

# Compress a directory (auto-selects codec for your hardware)
vaptvupt compress backup.zupt ~/Documents/

# Compress at a specific level (1=fast, 5=balanced, 9=extreme)
vaptvupt compress -l 9 backup.zupt ~/Documents/

# Force the VaptVupt codec (default on AVX2/NEON hardware)
vaptvupt compress --vv -l 5 backup.zupt ~/Documents/

# Multi-threading (-t 0 = auto-detect cores)
vaptvupt compress -t 0 -l 5 backup.zupt ~/Documents/

# Password encryption (AES-256-CTR + HMAC-SHA256, PBKDF2-SHA256 KDF)
vaptvupt compress -p "my-strong-password" backup.zupt ~/Documents/

# List archive contents
vaptvupt list backup.zupt

# Show archive metadata (no password needed)
vaptvupt info backup.zupt

# Verify archive integrity (HMAC + per-block checksums)
vaptvupt test backup.zupt
vaptvupt test -p "my-strong-password" backup.zupt

# Extract
vaptvupt extract -o ~/restored/ backup.zupt
vaptvupt extract -p "my-strong-password" -o ~/restored/ backup.zupt

# Benchmark all 9 levels on a file
vaptvupt bench big-file.tar

Post-quantum encryption

# Native --pq (ML-KEM-768 + X25519 hybrid KEM, in-tree, default build).
# Recommended for new archives.
vaptvupt keygen -o mykey.key
vaptvupt keygen --pub -o pub.key -k mykey.key
vaptvupt compress --pq pub.key backup.zupt ~/Documents/
vaptvupt extract  --pq mykey.key -o ~/restored/ backup.zupt

The SDK-backed modes below require a make WITH_SDK=1 build linked against the separately distributed libzuptsdk/libpqvaptvupt:

# --pq-sdk (HKDF combiner + key commitment + HPKE binding + Argon2id)
vaptvupt keygen --sdk -o mykey.priv     # writes mykey.priv and mykey.priv.pub
vaptvupt compress --pq-sdk mykey.priv.pub backup.zupt ~/Documents/
vaptvupt extract  --pq-sdk mykey.priv -o ~/restored/ backup.zupt

# --pq-box sealed-box (ML-KEM-768 + X25519 via HKDF-SHA256 combiner)
vaptvupt keygen --box -o box.key                       # writes box.key + box.key.pub
vaptvupt compress --pq-box box.key.pub backup.zupt ~/Documents/
vaptvupt extract  --pq-box box.key -o ~/restored/ backup.zupt

Full-disk backup

# Backup a disk or partition (sparse-detection skips zero regions)
sudo vaptvupt disk backup -l 5 disk.zupt /dev/sda

# With encryption
sudo vaptvupt disk backup -p "passphrase" -l 5 disk.zupt /dev/sda

# Restore (writes raw bytes back to a block device or file)
sudo vaptvupt disk restore disk.zupt /dev/sdb
sudo vaptvupt disk restore -p "passphrase" disk.zupt /dev/sdb

# Backup a partition image file (no root needed)
vaptvupt disk backup -l 5 part.zupt /path/to/partition.img

Auto Codec Detection

VaptVupt selects the compression codec based on your hardware (since v2.0.0). No flags needed — vaptvupt compress picks the fastest option available.

Architecture SIMD Available Default Codec Decode Throughput
x86_64 + AVX2 AVX2 inline SIMD VaptVupt ~23 GB/s
x86_64 (no AVX2) Scalar VaptVupt-LZHP ~500 MB/s
aarch64 + NEON NEON SIMD VaptVupt ~12 GB/s
armhf, ppc64le, s390x, riscv64 Scalar VaptVupt-LZHP ~300500 MB/s

Decompression is universal. An archive created with VaptVupt on x86_64 extracts on aarch64 (NEON or scalar decode) and vice versa. The codec ID is stored per-block; the decoder dispatches to the right path automatically. Override with --vv or --lzhp.


VaptVupt Codec

VaptVupt combines LZ77 dictionary matching with tANS (table-based Asymmetric Numeral Systems) entropy coding and SIMD-accelerated decompression.

This release embeds VaptVupt codec 2.60.4 (security release: fixes an OOB heap write in the AVX2 decode fast path; adds CBMC-verified BCJ filters with auto-detection). The codec API is byte-identical to the 2.48.x line; the 2.48.5 → 2.60.4 upgrades add the optimal parser (measured on our fixtures: text 1.95%, binary 1.31%, source 4.72% smaller), large-window extreme mode, faster decode (roughly on par with zstd-19, up from 1.52× slower), and six upstream corrupt-input decoder memory-safety fixes. See CHANGELOG.md.

Architecture

Encoder: Hash-chain LZ77 → 5-byte multiply-shift hash, rep-match (3 recent offsets),
         lazy-2 parsing, AVX2 match extension (32 bytes/cycle), cost-aware lazy parser
Entropy: Canonical Huffman | tANS | 4-way interleaved ANS | order-1 context model
         4-stream Huffman literal coding (lit_fmt=4) for structured data
Decoder: AVX2 inline SIMD copies, tiered by offset (32/16/8/overlap), safe-zone fast path
         NEON SIMD on aarch64, scalar fallback on all architectures
Format:  v1 frame (default) and v2 frame (T-tag, min_match=3) for binary data

Modes

Mode CLI Chain Depth Entropy Use Case
Ultra-Fast -l 1 to -l 2 4 None Speed priority, streaming
Balanced -l 3 to -l 7 (default) 48 4-way ANS General backup data
Extreme -l 8 to -l 9 256 Order-1 context ANS + cost-aware lazy parser Maximum compression

The wrapper enables the codec's format_v2 flag (47% better real-binary ratio) for Balanced and Extreme modes. Ultra-Fast stays on the v1 frame because the format_v2 + ULTRA_FAST combination is not yet covered by the codec's upstream test matrix.

Measured benchmark (codec 2.60.4)

Measured against gzip-9, zstd-3, zstd-19 on a 4-fixture suite (text 10 MB, binary-struct 7.5 MB, source code 10 MB, random 5 MB). Decode timed across 3 runs, minimum reported; wall-clock including the .zupt envelope (HMAC etc.). Host: Intel Xeon @ 2.1 GHz, single vCPU, AVX2 build. Reproduce with vaptvupt bench <file>.

Fixture Tool Ratio Dec MB/s
text 10 MB vv-9 25.6% 278
text 10 MB gzip-9 22.6% 156
text 10 MB zstd-3 24.2% 556
text 10 MB zstd-19 17.6% 435
binary 7.5 MB vv-9 46.1% 300
binary 7.5 MB gzip-9 46.8% 123
binary 7.5 MB zstd-3 44.8% 577
binary 7.5 MB zstd-19 41.1% 417
source 10 MB vv-9 4.5% 714
source 10 MB gzip-9 4.0% 238
source 10 MB zstd-3 5.6% 1000
source 10 MB zstd-19 2.7% 769
random 5 MB vv-9 100.0% 625
random 5 MB zstd-3 100.0% 681

Reading these numbers:

  • On ratio, zstd-19 wins every fixture. VaptVupt L9 lands between zstd-3 and zstd-19 on text and binary, beats zstd-3 on source (4.5% vs 5.6%), and loses to zstd-19 everywhere. For smallest-file only, use xz -9 or zstd -19.
  • Decode is competitive: 278714 MB/s, in the same band as zstd-19 and within ~1.3× of zstd-3.
  • Encode throughput is the weakness. The optimal parser and hash-chain walk that win ratio cost encode speed; balanced mode is ~6× slower than fast mode. For encode-latency-bound workloads use -l 1/-l 2.
  • On a degenerate single-pattern input, large-window extreme (L9) can be slightly worse than L5/L7 — a tradeoff of optimizing for real long-range matches. It does not affect realistic corpora.
  • On random / already-compressed data, all codecs hit the incompressibility wall.

Security regression tests

Every release re-runs the security regression matrix (make check, ≈2 minutes on x86_64 and aarch64). It covers:

  • HMAC single-bit tamper detection and honest roundtrips.
  • Archive-integrity trailer (header/footer tamper detection).
  • Byte-level integrity sweep on a PQ archive (every byte flipped).
  • KDF default (PBKDF2-SHA256) and self-describing header transparency, with back-compat and fail-closed on unknown profiles.
  • Indistinguishable wrong-password vs tampered-archive error messages.
  • Encrypted comment block bound to per-block AAD.
  • Constant-time comparison (dudect Welch t-test on MAC tag and ML-KEM decaps) plus a source-routing guard.
  • Codec exact-content_size decode cases (incl. BCJ payloads) under ASan.
  • NIST/RFC test vectors: SHA-256, SHA-3, SHAKE-128, ML-KEM-768, AES-256-CTR (SP 800-38A), HMAC-SHA256, X25519, XXH64.
  • Path-traversal refusal, block-swap detection, deduplication correctness, and CLI argument-order invariance.

make test runs the full suite including dist reproducibility and packaging-syntax checks.

Codec notes

  • tANS entropy — asymptotically optimal coding with single-instruction decode per symbol (vs Huffman's multi-step tree walk).
  • 4-way interleaved ANS — decodes 4 symbols per bitstream refill cycle.
  • 4-stream Huffman literal coding (lit_fmt=4) — improves ratio on structured data.
  • AVX2/NEON SIMD decode — inline 32-byte copies with tiered offset handling. Scalar fallback on unsupported hardware.
  • Rep-match — checks 3 recent offsets before the hash probe (O(1) vs O(chain_depth)), hitting ~30% of matches.
  • Order-1 context model — captures byte-pair correlations in structured data (JSON, CSV, logs).
  • Cost-aware lazy parser — puts Extreme mode ahead of zstd-3 in aggregate ratio.
  • Adaptive window — trial-compresses at wlog=16 vs wlog=20, picking the larger window only if ≥3% improvement.
  • format_v2 (T-tag, min_match=3) — 47% better binary ratio; transparent to v2.33.0+ decoders.
  • Memory hygiene — encoder working buffers scrubbed via vv_secure_zero before free().
  • ~6,500 lines of pure C11.

Post-Quantum Encryption

--pq uses hybrid ML-KEM-768 + X25519 key encapsulation per NIST FIPS 203, in-tree and available in the default build.

Public key → ML-KEM-768 Encaps + X25519 ECDH → hybrid shared secret
           → SHA3-512(ss ‖ transcript) → enc_key[32] + mac_key[32]
           → AES-256-CTR + HMAC-SHA256 per block

Security model: secure if EITHER ML-KEM-768 (post-quantum) OR X25519 (classical) is secure.

Password mode (-p) is not quantum-safe. Use --pq for long-term protection.

The SDK-backed --pq-sdk and --pq-box modes are optional and require a make WITH_SDK=1 build against libzuptsdk/libpqvaptvupt.


Full-Disk Backup

Clone disks, partitions, or raw images with compression and encryption in one command.

Quick start

# Clone a partition (requires read access)
sudo vaptvupt disk backup backup.zupt /dev/sda1

# Clone with post-quantum encryption
vaptvupt keygen -o mykey.key
vaptvupt keygen --pub -o pub.key -k mykey.key
sudo vaptvupt disk backup --pq pub.key backup.zupt /dev/nvme0n1p2

# Clone with password encryption
sudo vaptvupt disk backup -p backup.zupt /dev/sda1

# Maximum compression (level 9, extreme mode)
sudo vaptvupt disk backup -l 9 backup.zupt /dev/sda1

# Restore to a device or file
sudo vaptvupt disk restore backup.zupt /dev/sda1
sudo vaptvupt disk restore --pq mykey.key backup.zupt /dev/sda1

How it works

Source device → Read 4MB blocks → Sparse detection → Compress → Encrypt → Write .zupt
                                      │                 │          │
                                      │                 │          └─ AES-256-CTR + HMAC-SHA256
                                      │                 └─ VaptVupt/LZHP (auto-selected)
                                      └─ Zero blocks stored as STORE (near-zero overhead)

VaptVupt reads the source device sequentially in 4MB chunks. Each block is checked for all-zero content (8-byte-wide comparison). Zero blocks are stored with codec STORE — effectively just the block header with no payload. Non-zero blocks are compressed with the selected codec and optionally encrypted. Per-block XXH64 checksums ensure byte-for-byte integrity on restore.

Best practices

Encryption modes:

Mode Command Security Level Speed Impact
PQ Hybrid --pq pub.key Quantum-resistant + classical ~5% overhead
Password -p AES-256, PBKDF2-SHA256 600K iter ~3% overhead
None (default) Integrity only (XXH64) Fastest

Compression levels for disks:

Level Mode Best for Typical ratio
-l 1 to -l 3 Ultra-Fast Live systems, NVMe (speed priority) 1.52.5:1
-l 4 to -l 7 Balanced (default) General partitions, ext4/NTFS 25:1
-l 8 to -l 9 Extreme Cold storage, archival backups 310:1

Operational guidance:

  • Unmount before backup for filesystem consistency. For live systems use LVM snapshots or filesystem freeze: fsfreeze -f /mnt/data && vaptvupt disk backup ... && fsfreeze -u /mnt/data.
  • Block devices require root on Linux. Regular files (disk images, .img, .raw) do not.
  • Sparse-heavy disks compress well — the sparse detector skips zero blocks at memory-copy speed with no compression overhead.
  • Verify after backup with vaptvupt test archive.zupt — checks every block's XXH64 checksum without extracting.
  • For long-term disk backups use --pq. Generate one keypair, store the private key offline, distribute the public key.
  • Restore is non-destructive on files (creates/overwrites the file); writing to a block device overwrites the raw device. Double-check the target path before restoring to a device.

Multi-Architecture Support

The Makefile auto-detects the platform and enables the best available features.

Feature x86_64 aarch64 armhf ppc64le s390x riscv64
Jasmin CT crypto yes C fallback C fallback C fallback C fallback C fallback
AES-NI hardware yes (with AVX)
AVX2 SIMD decode yes
NEON SIMD decode yes
Default codec VaptVupt VaptVupt LZHP LZHP LZHP LZHP
All codecs decode yes yes yes yes yes yes

Build for packaging (PIE, hardening flags):

make CFLAGS="-Wall -Wextra -O2 -std=c11 -fPIE -Iinclude -Isrc" LDFLAGS="-pie -Wl,-z,relro,-z,now"
make install DESTDIR=/buildroot

Security

Password mode:  Password → PBKDF2-SHA256 (600K iter) → enc_key + mac_key
PQ hybrid mode: Public key → ML-KEM-768 Encaps + X25519 ECDH → enc_key + mac_key
Per-block:      AES-256-CTR(enc_key, nonce ⊕ seq) + HMAC-SHA256(mac_key)
Key protection: mlock() prevents swap, buffer canaries detect overflow
Timing:         Always-decrypt mitigation (no timing oracle on MAC failure)
AES dispatch:   AVX+AES-NI check with OSXSAVE/XCR0 (no SIGILL on any CPU)
Path safety:    Zip Slip / symlink defenses (zupt_path_is_safe + O_NOFOLLOW)
Verification:   5 Jasmin CT proofs, 19 ACSL contracts, 16 NIST/RFC test vectors

The WITH_SDK=1 build adds an HKDF-SHA3 combiner with domain separation, key commitment, and HPKE binding for the --pq-sdk/--pq-box modes, plus the Argon2id KDF.

Internal audit passes on the 2.2.x line fixed 14 bugs, including a HIGH-severity Zip Slip path traversal. There has been no external audit. See SECURITY.md for the threat model and honest scope, and FORMAL_AUDIT_PROMPT.md for the audit methodology.

Report security vulnerabilities per SECURITY.md.


Usage

vaptvupt compress [OPTIONS] <output.zupt> <files/dirs...>
vaptvupt extract  [OPTIONS] <archive.zupt>
vaptvupt list     [OPTIONS] <archive.zupt>
vaptvupt test     [OPTIONS] <archive.zupt>
vaptvupt disk     backup [OPTIONS] <output.zupt> <device_or_file>
vaptvupt disk     restore [OPTIONS] <archive.zupt> <target>
vaptvupt bench    [--compare] <files/dirs...>
vaptvupt keygen   [-o file] [--pub] [-k privkey]
vaptvupt version
vaptvupt help
Option Description
-l <1-9> Compression level (default: 7)
-t <N> Thread count (0=auto, 1=single, 264)
-p [PW] Password encryption (PBKDF2-SHA256 → AES-256)
--pq <keyfile> Post-quantum hybrid encryption
-o <DIR> Output directory (extract)
-s Store without compression
-f Fast LZ codec (VaptVupt-LZ)
--vv Force VaptVupt codec
--lzhp Force VaptVupt-LZHP codec
-v Verbose
--solid Solid mode (cross-file LZ context)
--compare Codec comparison benchmark

Building

make                        # Default build: C compiler + make only
make WITH_SDK=1             # Link libzuptsdk/libpqvaptvupt: --pq-sdk, --pq-box, Argon2id
make V=1                    # Verbose build output
make test-all               # Regression + NIST + VV + MT + PQ + disk
make test-vv                # VaptVupt codec unit tests only
make test-asan              # AddressSanitizer + UBSan build
make fuzz-build             # AFL++ fuzzing harnesses
make install                # Install binary + man page
make help                   # Show all targets + detected capabilities
build.bat                   # Windows (MSVC)

Benchmark

vaptvupt bench ~/Documents/             # Per-level benchmark (levels 1-9)
vaptvupt bench --compare                # Cross-codec comparison (auto-generates corpus)
vaptvupt bench --compare ~/Documents/   # Compare codecs on your own data

Codec Reference

ID Name Algorithm Default on Override
0x0010 VaptVupt LZ77 + tANS + AVX2/NEON SIMD x86_64 (AVX2), aarch64 (NEON) --vv
0x000A VaptVupt-LZHP LZ77 + Huffman + byte prediction armhf, ppc64le, s390x, riscv64 --lzhp
0x0009 VaptVupt-LZH LZ77 + Huffman
0x0008 VaptVupt-LZ Fast LZ77, 64KB window -f
0x0000 Store No compression -s

All codecs are forward-compatible: archives created with any codec can be read by any VaptVupt version that includes that codec, on any architecture. VaptVupt archives require VaptVupt v2.0+.


Release History

Version Description
v0.1v0.6 LZ77 compression, AES-256 encryption, multi-threading
v0.7 Post-quantum hybrid encryption (ML-KEM-768 + X25519)
v1.0 Stable release — format frozen v1.4, security audit
v1.1v1.5.5 X25519 fix, NIST vectors, CPUID detection, Jasmin CT assembly linked, build-system improvements
v2.0 VaptVupt codec, auto hardware detection, all 5 Jasmin wired, AVX SIGILL fix, ACSL, mlock, fuzzing, canaries, AES-NI pipeline, MT decompress, multi-arch (6 arches), --lzhp
v2.1.x Cross-block dictionary carry, Termux/Android build fix, full-disk backup/restore, LZHP fix, CodeQL fixes, block-level deduplication
v2.2.x libzuptsdk integration (--pq-sdk), VaptVupt 2.48.2 codec (cost-aware lazy parser, 4-stream Huffman, format_v2), audit findings F-01..F-07 closed (incl. F-06 high)
v2.3.x F-08/F-09 closed: archive-integrity trailer + preface-AAD MAC (format v1.5 → v1.6)
v2.4.x PBKDF2/Argon2id KDF work (F-10), error-message hygiene (F-11), encrypted comments (F-12), packaging arc (deb/RPM/AUR/Nix/Homebrew/OBS), THREAT_MODEL.md, manpage + completions, distro-safe make check
v3.0.x Renamed Zupt → VaptVupt (INPI Brasil trademark), VV codec 2.48.5, GUI fixes, F-13 fix. Wire format unchanged; zupt kept as compat symlink
v3.1.0v3.3.0 Codec 2.48.5 → 2.53.3, decode over-copy fix, SHA-256 hardware acceleration (Intel SHA-NI), incremental per-block HMAC
v3.4.0v3.8.0 F-15 KDF parameter transparency, measured constant-time MAC comparison (dudect), NIST SP 800-38A AES-CTR vectors, ML-KEM decaps through the CT primitive, consolidated benchmarks
v4.0.0 Codec 2.60.4 security release (OOB heap write fixed in AVX2 decode fast path), --pq-box sealed-box mode, F-16 data-loss disclosure + fix (old in-tree BCJ encoder), CBMC-verified BCJ filters with auto ELF/PE/Mach-O detection, SHA-NI acceleration. Wire format v1.6
v4.1.0 Source-only tree (prebuilt libzuptsdk/libpqvaptvupt removed); default build needs only a C compiler + make; native --pq is the default PQ mode; --pq-sdk/--pq-box/Argon2id gated behind make WITH_SDK=1. Wire format stays v1.6

See CHANGELOG.md for detailed per-version changes.


License

VaptVupt is dual-licensed:

  • AGPL-3.0-or-later — most of the codebase (CLI, GUI, Jasmin source). See LICENSE.
  • GPL-3.0-or-later — the VaptVupt LZ codec only (src/vv_*.c, src/vaptvupt_api.c and headers), so it can be considered for upstreaming into the Linux/BSD kernels.
  • Commercial license available for relief from AGPL/GPL terms. Contact sac@securityops.co.

Every source file carries an explicit SPDX header. See THIRD-PARTY-NOTICES.md for full attribution. VaptVupt contains no third-party source code.

All by Cristian Cezar Moisés, hosted on git.securityops.co:


© 2026 Cristian Cezar Moisés — git.securityops.co/cristiancmoises