Enhanced Secure Folder Security

[priyankeshh]

Fixes #349

This PR addresses the security vulnerabilities identified in the secure folder feature, focusing on encryption, key management, and access control.

Key Changes:

• Argon2id Implementation: Replaced the previous key derivation function with Argon2id for stronger password hashing. This includes:

  • Increased memory cost (64MB)
  • Appropriate iteration count
  • Parallelism factor optimized for desktop use

• Password Strength Validation: Implemented robust password validation to enforce complexity requirements, including:

  • Minimum length of 8 characters
  • Requirement for at least one uppercase letter and one number

• Secure File Deletion: Enhanced file deletion process to securely erase files by:

  • Performing multiple overwrite passes with different patterns (zeros, ones, alternating bits) to minimize data recovery risks.

• AES-256-GCM Encryption: Ensured robust encryption using AES-256-GCM with:

  • Proper salt generation
  • Secure nonce handling

• Comprehensive Error Handling: Improved error handling throughout the security pipeline to provide informative messages without leaking sensitive information.

These changes significantly enhance the security of the secure folder feature, addressing the identified vulnerabilities and aligning with industry best practices for encryption and secure data handling.