rZip / docs / encrypted-archives

Encrypted Archives, Security and Integrity

AES-256 standard encryption on ZIP and 7z, header filename protection, RAM password management, split volumes, and archive verification.

Strong Encryption Standards

rZip leverages both the in-process libarchive engine and the sandboxed 7zz (7-Zip 26.03) binary to handle high-security encrypted containers:

  • 7z Header and Filename Encryption (-mhe): Beyond encrypting file data payloads, 7z supports full header encryption. Without entering the correct password, unauthorized third parties cannot even view file names, directory trees, or file sizes.
  • ZIP WinZip AES-256: The modern 256-bit AES standard for .zip archives, universally supported across Mac, Windows, and Linux.
  • Protected RAR (v4 & v5): Seamless reading and extraction of password-protected RAR archives, including those with encrypted file tables (-hp).
  • Legacy ZipCrypto: Read-only extraction support for older archives created on legacy systems.

Volatile In-Memory Password Security

[!IMPORTANT] To guarantee complete confidentiality:

  • Passwords entered by the user are never persisted to disk, cached in application support folders, or written to system logs.
  • Cryptographic symmetric keys live exclusively within volatile RAM associated with the active window session and are purged immediately when the window is closed (⌘W).
  • When dragging an encrypted item directly into Finder, rZip requests the password upon drop (and prompts again if invalid).

Multi-Volume Spanned Archives

When large compressed archives are split across sequential files:

  • 7-Zip convention: archive.7z.001, archive.7z.002…
  • RAR convention: archive.part1.rar, archive.part2.rar or archive.r00, archive.r01…
  • Split ZIP convention: backup.zip, backup.z01, backup.z02…
  • Split compressed TAR: data.tar.gz.001, data.tar.gz.002…

rZip allows opening the archive starting from any volume in the sequence:

  1. Drag any volume from the set into the rZip window.
  2. Through the macOS sandbox FolderAccess workflow, rZip locates all associated volumes in the directory and reconstructs the full archive structure automatically.

Archive Integrity Verification

From the main menu or toolbar, select Verify Integrity:

  • rZip audits the cryptographic integrity and CRC/SHA checksums of every internal entry without extracting anything to disk.
  • A dedicated progress banner (VerificationBanner) tracks real-time progress, alerting you immediately to truncated or corrupted blocks.