pdu

Small, fast, and correct L2/L3/L4 packet parser.

Author: Alex Forster \ License: Apache-2.0

Small

• Fully-featured no_std support
• No Crate dependencies and no macros
• Internet protocols only: application-layer protocols are out of scope

Fast

• Lazy parsing: only the fields that you access are parsed
• Zero-copy construction: no heap allocations are performed

Correct

• Tested against Wireshark to ensure all packet fields are parsed correctly
• Fuzzed using Honggfuzz to ensure invalid input does not cause panics
• Does not use any unsafe code

Supported Protocols

The following protocol hierarchy can be parsed with this library:

• Ethernet (including vlan)
  • ARP
  • IPv4 (including options)
    • TCP (including options)
    • UDP
    • ICMP
    • GREv0
    • ...Ethernet, IPv4, IPv6...
  • IPv6 (including extension headers)
    • TCP (including options)
    • UDP
    • ICMPv6
    • GREv0
    • ...Ethernet, IPv4, IPv6...

In addition, unrecognized upper protocols are accessible as bytes via Raw enum variants.

Getting Started

Cargo.toml

toml [dependencies] pdu = "1.0"

Examples

```rust use pdu::*;

// parse a layer 2 (Ethernet) packet using EthernetPdu::new()

fn main() { let packet: &[u8] = &[ 0x68, 0x5b, 0x35, 0xc0, 0x61, 0xb6, 0x00, 0x1d, 0x09, 0x94, 0x65, 0x38, 0x08, 0x00, 0x45, 0x00, 0x00, 0x3b, 0x2d, 0xfd, 0x00, 0x00, 0x40, 0x11, 0xbc, 0x43, 0x83, 0xb3, 0xc4, 0x2e, 0x83, 0xb3, 0xc4, 0xdc, 0x18, 0xdb, 0x18, 0xdb, 0x00, 0x27, 0xe0, 0x3e, 0x05, 0x1d, 0x07, 0x15, 0x08, 0x07, 0x65, 0x78, 0x61, 0x6d, 0x70, 0x6c, 0x65, 0x08, 0x07, 0x74, 0x65, 0x73, 0x74, 0x41, 0x70, 0x70, 0x08, 0x01, 0x31, 0x0a, 0x04, 0x1e, 0xcc, 0xe2, 0x51, ];

match EthernetPdu::new(&packet) {
    Ok(ethernet_pdu) => {
        println!("[ethernet] destination_address: {:x?}", ethernet_pdu.destination_address().as_ref());
        println!("[ethernet] source_address: {:x?}", ethernet_pdu.source_address().as_ref());
        println!("[ethernet] ethertype: 0x{:04x}", ethernet_pdu.ethertype());
        if let Some(vlan) = ethernet_pdu.vlan() {
            println!("[ethernet] vlan: 0x{:04x}", vlan);
        }
        // upper-layer protocols can be accessed via the inner() method
        match ethernet_pdu.inner() {
            Ok(Ethernet::Ipv4(ipv4_pdu)) => {
                println!("[ipv4] source_address: {:x?}", ipv4_pdu.source_address().as_ref());
                println!("[ipv4] destination_address: {:x?}", ipv4_pdu.destination_address().as_ref());
                println!("[ipv4] protocol: 0x{:02x}", ipv4_pdu.protocol());
                // upper-layer protocols can be accessed via the inner() method (not shown)
            }
            Ok(Ethernet::Ipv6(ipv6_pdu)) => {
                println!("[ipv6] source_address: {:x?}", ipv6_pdu.source_address().as_ref());
                println!("[ipv6] destination_address: {:x?}", ipv6_pdu.destination_address().as_ref());
                println!("[ipv6] protocol: 0x{:02x}", ipv6_pdu.computed_protocol());
                // upper-layer protocols can be accessed via the inner() method (not shown)
            }
            Ok(other) => {
                panic!("Unexpected protocol {:?}", other);
            }
            Err(e) => {
                panic!("EthernetPdu::inner() parser failure: {:?}", e);
            }
        }
    }
    Err(e) => {
        panic!("EthernetPdu::new() parser failure: {:?}", e);
    }
}

} ```

```rust use pdu::*;

// parse a layer 3 (IP) packet using Ip::new()

fn main() { let packet: &[u8] = &[ 0x45, 0x00, 0x00, 0x3b, 0x2d, 0xfd, 0x00, 0x00, 0x40, 0x11, 0xbc, 0x43, 0x83, 0xb3, 0xc4, 0x2e, 0x83, 0xb3, 0xc4, 0xdc, 0x18, 0xdb, 0x18, 0xdb, 0x00, 0x27, 0xe0, 0x3e, 0x05, 0x1d, 0x07, 0x15, 0x08, 0x07, 0x65, 0x78, 0x61, 0x6d, 0x70, 0x6c, 0x65, 0x08, 0x07, 0x74, 0x65, 0x73, 0x74, 0x41, 0x70, 0x70, 0x08, 0x01, 0x31, 0x0a, 0x04, 0x1e, 0xcc, 0xe2, 0x51, ];

match Ip::new(&packet) {
    Ok(Ip::Ipv4(ipv4_pdu)) => {
        println!("[ipv4] source_address: {:x?}", ipv4_pdu.source_address().as_ref());
        println!("[ipv4] destination_address: {:x?}", ipv4_pdu.destination_address().as_ref());
        println!("[ipv4] protocol: 0x{:02x}", ipv4_pdu.protocol());
        // upper-layer protocols can be accessed via the inner() method (not shown)
    }
    Ok(Ip::Ipv6(ipv6_pdu)) => {
        println!("[ipv6] source_address: {:x?}", ipv6_pdu.source_address().as_ref());
        println!("[ipv6] destination_address: {:x?}", ipv6_pdu.destination_address().as_ref());
        println!("[ipv6] protocol: 0x{:02x}", ipv6_pdu.computed_protocol());
        // upper-layer protocols can be accessed via the inner() method (not shown)
    }
    Err(e) => {
        panic!("Ip::new() parser failure: {:?}", e);
    }
}

} ```