feat(encryption) [1/N] Support encryption: Add crypto for AES-GCM

[xanderbailey]

Add Core Encryption Primitives for Iceberg Encryption Support.

Part of #2034

Summary

This PR introduces the foundational cryptographic primitives needed for implementing encryption in iceberg-rust, providing AES-GCM encryption operations that match the Java implementation's behavior and data format.

Motivation

Iceberg's Java implementation supports table-level encryption to protect sensitive data at rest. To achieve feature parity and ensure interoperability between Java and Rust implementations, we need to build encryption support from the ground up. This PR provides the core cryptographic operations that will serve as the foundation for the complete encryption feature.

Changes

New Module: encryption

Added a new encryption module with core AES-GCM cryptographic operations:

• encryption/crypto.rs - Core encryption implementation
  • EncryptionAlgorithm enum supporting AES-128-GCM as this is the only algorithm currently supported in arrow parquet
  • SecureKey struct with automatic memory zeroization for security
  • AesGcmEncryptor providing encrypt/decrypt operations with AAD support

Key Features

1. Java-Compatible Format: Ciphertext format matches Java's implementation exactly:
   [12-byte nonce][encrypted data][16-byte GCM authentication tag]
2. This ensures files encrypted by Java can be decrypted by Rust and vice versa.
3. Secure Key Handling: Uses the zeroize crate to automatically clear encryption keys from memory when dropped, preventing key material from lingering in memory.
4. Additional Authenticated Data (AAD): Full support for AAD to ensure integrity of associated metadata that isn't encrypted.
5. Comprehensive Testing: 8 tests covering:
   - Round-trip encryption/decryption for both AES-128 and AES-256
   - AAD validation
   - Empty plaintext handling
   - Tamper detection
   - Format compatibility verification

Dependencies Added

• aes-gcm = "0.10" - Industry-standard AES-GCM implementation
• zeroize = "1.7" - Secure memory cleanup for encryption keys

Compatibility

This implementation directly corresponds to Java's https://github.com/apache/iceberg/blob/main/core/src/main/java/org/apache/iceberg/encryption/Ciphers.java:

Java Class	Rust Implementation
Ciphers.AesGcmEncryptor	AesGcmEncryptor::encrypt()
Ciphers.AesGcmDecryptor	AesGcmEncryptor::decrypt()
EncryptionAlgorithm.AES_GCM	EncryptionAlgorithm::Aes128Gcm

Testing

Future Work

This PR is the first in a series to implement full encryption support. Upcoming PRs will add:

1. Table properties for encryption configuration
2. Key management interfaces (KeyManagementClient trait)
3. EncryptionManager implementation
4. Native Parquet encryption integration
5. AWS KMS support
6. Integration with Table and FileIO

Review Notes

• This PR is intentionally minimal and self-contained
• No existing code paths are modified - this is purely additive
• The module is public but won't be used until future PRs wire it up
• Format compatibility with Java has been prioritized to ensure interoperability

Which issue does this PR close?

• Closes #. Encryption - Add AES-GCM encryption utilities #2035

What changes are included in this PR?

Are these changes tested?

Yes

[mbutrovich]

This is awesome! I will take a look since I did a lot of the PME support in Comet. Regarding AES-256-GCM support, last I looked Arrow-rs' Parquet reader only supported 128. Is that not the case anymore?

[xanderbailey]

You are correct by the looks of it! https://github.com/apache/arrow-rs/blob/main/parquet/src/encryption/ciphers.rs

[hsiang-c]

@xanderbailey Thank you for the great work on encryption support!

Regarding arror-rs, I removed the hardcoded AES-128 constraint w/ apache/arrow-rs#9203, hope that helps a bit. Because we're using PME with AES-256

cc @mbutrovich

[xanderbailey]

This helps a bunch thanks!