Quic Parser

Zero-copy QUIC Initial packet parser with optional payload decryption.

quic-parser extracts headers, connection IDs, and tokens from QUIC Initial packets without allocating. When a crypto backend is enabled, it can also decrypt payloads and reassemble CRYPTO frames for both QUIC v1 (RFC 9001) and v2 (RFC 9369).

Features

• Header Parsing: Zero-copy parsing of QUIC Initial packet headers with no crypto dependencies.
• Connection ID Peek: Fast extraction of Destination Connection IDs from both Long and Short Header packets.
• VarInt Decoding: QUIC variable-length integer decoder (RFC 9000 Section 16).
• Payload Decryption: HKDF-SHA256 key derivation, AES-ECB header protection removal, and AES-128-GCM AEAD decryption.
• Frame Extraction: Parse CRYPTO frames from decrypted payloads and reassemble them into a contiguous byte stream.
• Dual Crypto Backend: Choose between ring and aws-lc-rs as the cryptographic provider.

Usage Examples

Check the examples directory for runnable code:

• Header Only: examples/parse_header.rs - Parse headers and peek at connection IDs without crypto.
• Full Decrypt: examples/decrypt_initial.rs - Decrypt a QUIC v1 Initial packet and extract the TLS ClientHello.

Installation

[dependencies]
quic-parser = { version = "0.1", features = ["full"] }

Feature Flags

License

Released under the MIT License © 2026 Canmi