mirror of
https://github.com/zaphar/icmp-socket.git
synced 2025-07-23 19:39:49 -04:00
1094 lines
33 KiB
Rust
1094 lines
33 KiB
Rust
// Copyright 2021 Jeremy Wall
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//
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// Licensed under the Apache License, Version 2.0 (the "License");
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// you may not use this file except in compliance with the License.
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// You may obtain a copy of the License at
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//
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// http://www.apache.org/licenses/LICENSE-2.0
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//
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// Unless required by applicable law or agreed to in writing, software
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// distributed under the License is distributed on an "AS IS" BASIS,
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// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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// See the License for the specific language governing permissions and
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// limitations under the License.
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//! Packet parsing and construction.
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//!
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//! Where possible we use traits to support a common API for constructing the
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//! ICMPv4 and ICMPv6 versions of the packets.
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//!
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//! Both packet types can be constructed from a slice: `&[u8]` via the [`TryFrom`] trait.
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//!
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//! # Examples
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//!
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//! Constructing an ICMPv4 echo request.
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//! ```
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//! # use icmp_socket::packet::*;
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//! let packet = Icmpv4Packet::with_echo_request(
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//! 42, // An identifier so you can recognize responses to your own packets.
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//! 0, // the first echo request packet in our sequence.
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//! "a payload big enough to matter".as_bytes().to_vec()
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//! ).unwrap();
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//! ```
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//!
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//! Parsing an ICMPv4 packet from a byte buffer.
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//! ```
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//! # use icmp_socket::packet::*;
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//! use std::convert::TryFrom;
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//! # let packet = Icmpv4Packet::with_echo_request(
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//! # 42, // An identifier so you can recognize responses to your own packets.
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//! # 0, // the first echo request packet in our sequence.
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//! # "a payload big enough to matter".as_bytes().to_vec()
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//! # ).unwrap();
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//! # let mut byte_buffer = vec![0; 20];
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//! # byte_buffer.extend(packet.get_bytes(true)); // convert a packet to bytes with a checksum.
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//! let parsed_packet = Icmpv4Packet::try_from(byte_buffer.as_slice()).unwrap();
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//! ```
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use std::convert::TryFrom;
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use byteorder::{BigEndian, ByteOrder};
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use std::net::Ipv6Addr;
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fn ipv6_sum_words(ip: &Ipv6Addr) -> u32 {
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ip.segments().iter().map(|x| *x as u32).sum()
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}
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fn sum_big_endian_words(bs: &[u8]) -> u32 {
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if bs.len() == 0 {
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return 0;
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}
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let len = bs.len();
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let mut data = &bs[..];
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let mut sum = 0u32;
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// Iterate by word which is two bytes.
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while data.len() >= 2 {
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sum += BigEndian::read_u16(&data[0..2]) as u32;
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// remove the first two bytes now that we've already summed them
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data = &data[2..];
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}
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if (len % 2) != 0 {
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// If odd then checksum the last byte
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sum += (data[0] as u32) << 8;
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}
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return sum;
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}
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/// Construct a packet for the EchoRequest messages.
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pub trait WithEchoRequest {
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type Packet;
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fn with_echo_request(
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identifier: u16,
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sequence: u16,
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payload: Vec<u8>,
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) -> Result<Self::Packet, IcmpPacketBuildError>;
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}
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/// Construct a packet for Echo Reply messages.
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/// This packet type is really only used for the ICMPv6 protocol.
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pub trait WithEchoReply {
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type Packet;
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fn with_echo_reply(
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identifier: u16,
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sequence: u16,
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payload: Vec<u8>,
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) -> Result<Self::Packet, IcmpPacketBuildError>;
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}
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/// Construct a packet for Destination Unreachable messages.
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pub trait WithUnreachable {
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type Packet;
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fn with_unreachable(code: u8, packet: Vec<u8>) -> Result<Self::Packet, IcmpPacketBuildError>;
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}
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/// Construct a packet for Parameter Problem messages.
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pub trait WithParameterProblem {
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type Packet;
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type Pointer;
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fn with_parameter_problem(
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code: u8,
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pointer: Self::Pointer,
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packet: Vec<u8>,
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) -> Result<Self::Packet, IcmpPacketBuildError>;
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}
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/// Construct a packet for Time Exceeded messages.
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pub trait WithTimeExceeded {
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type Packet;
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fn with_time_exceeded(code: u8, packet: Vec<u8>) -> Result<Self::Packet, IcmpPacketBuildError>;
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}
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/// The possible Icmpv6 Message types.
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#[derive(Debug, PartialEq)]
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pub enum Icmpv6Message {
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// NOTE(JWALL): All of the below integers should be parsed as big endian on the
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// wire.
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Unreachable {
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_unused: u32,
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invoking_packet: Vec<u8>,
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},
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PacketTooBig {
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mtu: u32,
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invoking_packet: Vec<u8>,
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},
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TimeExceeded {
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_unused: u32,
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invoking_packet: Vec<u8>,
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},
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ParameterProblem {
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pointer: u32,
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invoking_packet: Vec<u8>,
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},
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PrivateExperimental {
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padding: u32,
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payload: Vec<u8>,
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},
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EchoRequest {
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identifier: u16,
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sequence: u16,
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payload: Vec<u8>,
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},
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EchoReply {
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identifier: u16,
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sequence: u16,
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payload: Vec<u8>,
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},
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}
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use Icmpv6Message::{
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EchoReply, EchoRequest, PacketTooBig, ParameterProblem, PrivateExperimental, TimeExceeded,
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Unreachable,
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};
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impl Icmpv6Message {
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/// Get this Icmpv6Message serialized to bytes.
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pub fn get_bytes(&self) -> Vec<u8> {
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let mut bytes = Vec::new();
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match self {
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Unreachable {
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_unused: field1,
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invoking_packet: field2,
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}
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| PacketTooBig {
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mtu: field1,
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invoking_packet: field2,
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}
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| TimeExceeded {
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_unused: field1,
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invoking_packet: field2,
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}
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| ParameterProblem {
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pointer: field1,
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invoking_packet: field2,
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}
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| PrivateExperimental {
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padding: field1,
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payload: field2,
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} => {
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let mut buf = vec![0; 4];
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BigEndian::write_u32(&mut buf, *field1);
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bytes.append(&mut buf);
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bytes.extend_from_slice(field2);
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}
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EchoRequest {
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identifier,
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sequence,
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payload,
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}
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| EchoReply {
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identifier,
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sequence,
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payload,
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} => {
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let mut buf = vec![0; 2];
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BigEndian::write_u16(&mut buf, *identifier);
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bytes.append(&mut buf);
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buf.resize(2, 0);
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BigEndian::write_u16(&mut buf, *sequence);
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bytes.append(&mut buf);
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bytes.extend_from_slice(payload);
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}
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}
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bytes
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}
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}
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#[derive(Debug)]
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pub struct Icmpv6Packet {
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// NOTE(JWALL): All of the below integers should be parsed as big endian on the
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// wire.
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pub typ: u8,
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pub code: u8,
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pub checksum: u16,
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pub message: Icmpv6Message,
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}
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/// Error type returned by parsing the ICMP packets.
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#[derive(Debug)]
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pub enum PacketParseError {
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/// Not enough bytes to properly parse the packet from.
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PacketTooSmall(usize),
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/// An unrecognized ICMP type.
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UnrecognizedICMPType(u8),
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}
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impl Icmpv6Packet {
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/// Construct a packet by parsing the provided bytes.
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pub fn parse<B: AsRef<[u8]>>(bytes: B) -> Result<Self, PacketParseError> {
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let bytes = bytes.as_ref();
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// NOTE(jwall): All ICMP packets are at least 8 bytes long.
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if bytes.len() < 8 {
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return Err(PacketParseError::PacketTooSmall(bytes.len()));
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}
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let (typ, code, checksum) = (bytes[0], bytes[1], BigEndian::read_u16(&bytes[2..4]));
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let next_field = BigEndian::read_u32(&bytes[4..8]);
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let payload = bytes[8..].to_owned();
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let message = match typ {
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1 => Unreachable {
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_unused: next_field,
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invoking_packet: payload,
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},
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2 => PacketTooBig {
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mtu: next_field,
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invoking_packet: payload,
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},
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3 => TimeExceeded {
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_unused: next_field,
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invoking_packet: payload,
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},
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4 => ParameterProblem {
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pointer: next_field,
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invoking_packet: payload,
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},
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100 | 101 | 200 | 201 => PrivateExperimental {
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padding: next_field,
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payload: payload,
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},
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128 => EchoRequest {
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identifier: BigEndian::read_u16(&bytes[4..6]),
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sequence: BigEndian::read_u16(&bytes[6..8]),
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payload: payload,
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},
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129 => EchoReply {
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identifier: BigEndian::read_u16(&bytes[4..6]),
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sequence: BigEndian::read_u16(&bytes[6..8]),
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payload: payload,
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},
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t => return Err(PacketParseError::UnrecognizedICMPType(t)),
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};
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return Ok(Icmpv6Packet {
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typ: typ,
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code: code,
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checksum: checksum,
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message: message,
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});
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}
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/// Get this packet serialized to bytes suitable for sending on the wire.
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pub fn get_bytes(&self, with_checksum: bool) -> Vec<u8> {
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let mut bytes = Vec::new();
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bytes.push(self.typ);
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bytes.push(self.code);
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let mut buf = Vec::with_capacity(2);
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buf.resize(2, 0);
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BigEndian::write_u16(&mut buf, if with_checksum { self.checksum } else { 0 });
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bytes.append(&mut buf);
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bytes.append(&mut self.message.get_bytes());
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return bytes;
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}
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/// Calculate the checksum for the packet given the provided source and destination
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/// addresses.
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pub fn calculate_checksum(&self, source: &Ipv6Addr, dest: &Ipv6Addr) -> u16 {
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// First sum the pseudo header
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let mut sum = 0u32;
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sum += ipv6_sum_words(source);
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sum += ipv6_sum_words(dest);
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// according to rfc4443: https://tools.ietf.org/html/rfc4443#section-2.3
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// the ip next header value is 58
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sum += 58;
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// Then sum the len of the message bytes and then the message bytes starting
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// with the message type field and with the checksum field set to 0.
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let bytes = self.get_bytes(false);
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let len = bytes.len();
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sum += len as u32;
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sum += sum_big_endian_words(&bytes);
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// handle the carry
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while sum >> 16 != 0 {
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sum = (sum >> 16) + (sum & 0xFFFF);
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}
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!sum as u16
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}
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/// Fill the checksum for the packet using the given source and destination
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/// addresses.
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pub fn with_checksum(mut self, source: &Ipv6Addr, dest: &Ipv6Addr) -> Self {
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self.checksum = self.calculate_checksum(source, dest);
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self
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}
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/// Construct a packet for Packet Too Big messages.
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pub fn with_packet_too_big(mtu: u32, packet: Vec<u8>) -> Result<Self, IcmpPacketBuildError> {
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Ok(Self {
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typ: 2,
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code: 0,
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checksum: 0,
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// TODO(jwall): Should we enforce that the packet isn't too big?
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// It is not supposed to be larger than the minimum IPv6 MTU
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message: PacketTooBig {
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mtu: mtu,
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invoking_packet: packet,
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},
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})
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}
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}
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impl WithEchoRequest for Icmpv6Packet {
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type Packet = Icmpv6Packet;
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fn with_echo_request(
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identifier: u16,
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sequence: u16,
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payload: Vec<u8>,
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) -> Result<Self::Packet, IcmpPacketBuildError> {
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Ok(Self {
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typ: 128,
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code: 0,
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checksum: 0,
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message: EchoRequest {
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identifier: identifier,
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sequence: sequence,
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payload: payload,
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},
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})
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}
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}
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impl WithEchoReply for Icmpv6Packet {
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type Packet = Icmpv6Packet;
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fn with_echo_reply(
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identifier: u16,
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sequence: u16,
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payload: Vec<u8>,
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) -> Result<Self, IcmpPacketBuildError> {
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Ok(Self {
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typ: 129,
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code: 0,
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checksum: 0,
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message: EchoReply {
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identifier: identifier,
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sequence: sequence,
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payload: payload,
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},
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})
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}
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}
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impl WithUnreachable for Icmpv6Packet {
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type Packet = Icmpv6Packet;
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fn with_unreachable(code: u8, packet: Vec<u8>) -> Result<Self, IcmpPacketBuildError> {
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if code > 6 {
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return Err(IcmpPacketBuildError::InvalidCode(code));
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}
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Ok(Self {
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typ: 1,
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code: code,
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checksum: 0,
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// TODO(jwall): Should we enforce that the packet isn't too big?
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// It is not supposed to be larger than the minimum IPv6 MTU
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message: Unreachable {
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_unused: 0,
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invoking_packet: packet,
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},
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})
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}
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}
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impl WithParameterProblem for Icmpv6Packet {
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type Packet = Icmpv6Packet;
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type Pointer = u32;
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fn with_parameter_problem(
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code: u8,
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pointer: Self::Pointer,
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packet: Vec<u8>,
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) -> Result<Self, IcmpPacketBuildError> {
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if code > 1 {
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return Err(IcmpPacketBuildError::InvalidCode(code));
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}
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Ok(Self {
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typ: 4,
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code: code,
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checksum: 0,
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message: ParameterProblem {
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pointer: pointer,
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invoking_packet: packet,
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},
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})
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}
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}
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impl WithTimeExceeded for Icmpv6Packet {
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type Packet = Icmpv6Packet;
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fn with_time_exceeded(code: u8, packet: Vec<u8>) -> Result<Self, IcmpPacketBuildError> {
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if code > 1 {
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return Err(IcmpPacketBuildError::InvalidCode(code));
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}
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Ok(Self {
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typ: 3,
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code: code,
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checksum: 0,
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// TODO(jwall): Should we enforce that the packet isn't too big?
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// It is not supposed to be larger than the minimum IPv6 MTU
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message: TimeExceeded {
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_unused: 0,
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invoking_packet: packet,
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},
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})
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}
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}
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impl TryFrom<&[u8]> for Icmpv6Packet {
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type Error = PacketParseError;
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fn try_from(b: &[u8]) -> Result<Self, Self::Error> {
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Icmpv6Packet::parse(b)
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}
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}
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/// Errors returned by constructors for a given packet.
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#[derive(Debug, PartialEq)]
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pub enum IcmpPacketBuildError {
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/// The code passed in for the payload was invalid for the message type.
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InvalidCode(u8),
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}
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use IcmpPacketBuildError::InvalidCode;
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impl std::fmt::Display for IcmpPacketBuildError {
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fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
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write!(
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f,
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"{}",
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match self {
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InvalidCode(c) => format!("Invalid Code: {}", c),
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}
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)
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}
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}
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|
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impl std::fmt::Display for PacketParseError {
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fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
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write!(
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f,
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"{}",
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match self {
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PacketParseError::PacketTooSmall(c) => format!("Packet Too Small size: {}", c),
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PacketParseError::UnrecognizedICMPType(t) => format!("UnrecognizedIcmpType({})", t),
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}
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)
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}
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}
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|
|
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impl From<IcmpPacketBuildError> for std::io::Error {
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fn from(err: IcmpPacketBuildError) -> Self {
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std::io::Error::new(std::io::ErrorKind::Other, format!("{}", err))
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}
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}
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|
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impl From<PacketParseError> for std::io::Error {
|
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fn from(err: PacketParseError) -> Self {
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std::io::Error::new(std::io::ErrorKind::Other, format!("{}", err))
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}
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}
|
|
|
|
/// The various messages for an Icmpv4 packet.
|
|
#[derive(Debug)]
|
|
pub enum Icmpv4Message {
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Unreachable {
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// type 3
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padding: u32,
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header: Vec<u8>,
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},
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TimeExceeded {
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// type 11
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padding: u32,
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header: Vec<u8>,
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},
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ParameterProblem {
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// type 12
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pointer: u8,
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padding: (u8, u16),
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header: Vec<u8>,
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},
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Quench {
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// type 4
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padding: u32,
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header: Vec<u8>,
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},
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Redirect {
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|
// type 5
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gateway: u32,
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header: Vec<u8>,
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},
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Echo {
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// type 8
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identifier: u16,
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sequence: u16,
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payload: Vec<u8>,
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},
|
|
EchoReply {
|
|
// type 0
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identifier: u16,
|
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sequence: u16,
|
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payload: Vec<u8>,
|
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},
|
|
Timestamp {
|
|
// type 13
|
|
identifier: u16,
|
|
sequence: u16,
|
|
originate: u32,
|
|
receive: u32,
|
|
transmit: u32,
|
|
},
|
|
TimestampReply {
|
|
// type 14
|
|
identifier: u16,
|
|
sequence: u16,
|
|
originate: u32,
|
|
receive: u32,
|
|
transmit: u32,
|
|
},
|
|
Information {
|
|
// type 15
|
|
identifier: u16,
|
|
sequence: u16,
|
|
},
|
|
InformationReply {
|
|
// type 16
|
|
identifier: u16,
|
|
sequence: u16,
|
|
},
|
|
}
|
|
|
|
impl Icmpv4Message {
|
|
/// Get this Icmpv4Message serialized as bytes.
|
|
pub fn get_bytes(&self) -> Vec<u8> {
|
|
let mut bytes = Vec::with_capacity(20);
|
|
match self {
|
|
Self::Unreachable {
|
|
// type 3
|
|
padding,
|
|
header,
|
|
}
|
|
| Self::TimeExceeded {
|
|
// type 11
|
|
padding,
|
|
header,
|
|
}
|
|
| Self::Quench {
|
|
// type 4
|
|
padding,
|
|
header,
|
|
}
|
|
| Self::Redirect {
|
|
// type 5
|
|
gateway: padding,
|
|
header,
|
|
} => {
|
|
let mut buf = vec![0; 4];
|
|
BigEndian::write_u32(&mut buf, *padding);
|
|
bytes.append(&mut buf);
|
|
bytes.extend_from_slice(header);
|
|
}
|
|
Self::Echo {
|
|
// type 8
|
|
identifier,
|
|
sequence,
|
|
payload,
|
|
}
|
|
| Self::EchoReply {
|
|
// type 0
|
|
identifier,
|
|
sequence,
|
|
payload,
|
|
} => {
|
|
let mut buf = vec![0; 2];
|
|
BigEndian::write_u16(&mut buf, *identifier);
|
|
bytes.append(&mut buf);
|
|
buf.resize(2, 0);
|
|
BigEndian::write_u16(&mut buf, *sequence);
|
|
bytes.append(&mut buf);
|
|
bytes.extend_from_slice(payload);
|
|
}
|
|
Self::ParameterProblem {
|
|
// type 12
|
|
pointer,
|
|
padding,
|
|
header,
|
|
} => {
|
|
bytes.push(*pointer);
|
|
bytes.push(padding.0);
|
|
let mut buf = vec![0, 2];
|
|
BigEndian::write_u16(&mut buf, padding.1);
|
|
bytes.append(&mut buf);
|
|
bytes.extend_from_slice(header);
|
|
}
|
|
Self::Timestamp {
|
|
// type 13
|
|
identifier,
|
|
sequence,
|
|
originate,
|
|
receive,
|
|
transmit,
|
|
}
|
|
| Self::TimestampReply {
|
|
// type 14
|
|
identifier,
|
|
sequence,
|
|
originate,
|
|
receive,
|
|
transmit,
|
|
} => {
|
|
let mut buf = vec![0, 2];
|
|
BigEndian::write_u16(&mut buf, *identifier);
|
|
bytes.append(&mut buf);
|
|
BigEndian::write_u16(&mut buf, *sequence);
|
|
bytes.append(&mut buf);
|
|
buf = vec![0, 4];
|
|
BigEndian::write_u32(&mut buf, *originate);
|
|
bytes.append(&mut buf);
|
|
BigEndian::write_u32(&mut buf, *receive);
|
|
bytes.append(&mut buf);
|
|
BigEndian::write_u32(&mut buf, *transmit);
|
|
bytes.append(&mut buf);
|
|
}
|
|
Self::Information {
|
|
// type 15
|
|
identifier,
|
|
sequence,
|
|
}
|
|
| Self::InformationReply {
|
|
// type 16
|
|
identifier,
|
|
sequence,
|
|
} => {
|
|
let mut buf = vec![0, 2];
|
|
BigEndian::write_u16(&mut buf, *identifier);
|
|
bytes.append(&mut buf);
|
|
BigEndian::write_u16(&mut buf, *sequence);
|
|
bytes.append(&mut buf);
|
|
}
|
|
}
|
|
bytes
|
|
}
|
|
}
|
|
|
|
/// An Icmpv4 Packet.
|
|
#[derive(Debug)]
|
|
pub struct Icmpv4Packet {
|
|
pub typ: u8,
|
|
pub code: u8,
|
|
pub checksum: u16,
|
|
pub message: Icmpv4Message,
|
|
}
|
|
|
|
impl Icmpv4Packet {
|
|
/// Parse an Icmpv4Packet from bytes including the IPv4 header.
|
|
pub fn parse<B: AsRef<[u8]>>(bytes: B) -> Result<Self, PacketParseError> {
|
|
let mut bytes = bytes.as_ref();
|
|
let mut packet_len = bytes.len();
|
|
if bytes.len() < 28 {
|
|
return Err(PacketParseError::PacketTooSmall(packet_len));
|
|
}
|
|
// NOTE(jwall) Because we use raw sockets the first 20 bytes are the IPv4 header.
|
|
bytes = &bytes[20..];
|
|
// NOTE(jwall): All ICMP packets are at least 8 bytes long.
|
|
packet_len = bytes.len();
|
|
let (typ, code, checksum) = (bytes[0], bytes[1], BigEndian::read_u16(&bytes[2..4]));
|
|
let message = match typ {
|
|
3 => Icmpv4Message::Unreachable {
|
|
padding: BigEndian::read_u32(&bytes[4..8]),
|
|
header: bytes[8..].to_owned(),
|
|
},
|
|
11 => Icmpv4Message::TimeExceeded {
|
|
padding: BigEndian::read_u32(&bytes[4..8]),
|
|
header: bytes[8..].to_owned(),
|
|
},
|
|
4 => Icmpv4Message::Quench {
|
|
padding: BigEndian::read_u32(&bytes[4..8]),
|
|
header: bytes[8..].to_owned(),
|
|
},
|
|
5 => Icmpv4Message::Redirect {
|
|
gateway: BigEndian::read_u32(&bytes[4..8]),
|
|
header: bytes[8..].to_owned(),
|
|
},
|
|
8 => Icmpv4Message::Echo {
|
|
identifier: BigEndian::read_u16(&bytes[4..6]),
|
|
sequence: BigEndian::read_u16(&bytes[6..8]),
|
|
payload: bytes[8..].to_owned(),
|
|
},
|
|
0 => Icmpv4Message::EchoReply {
|
|
identifier: BigEndian::read_u16(&bytes[4..6]),
|
|
sequence: BigEndian::read_u16(&bytes[6..8]),
|
|
payload: bytes[8..].to_owned(),
|
|
},
|
|
15 => Icmpv4Message::Information {
|
|
identifier: BigEndian::read_u16(&bytes[4..6]),
|
|
sequence: BigEndian::read_u16(&bytes[6..8]),
|
|
},
|
|
16 => Icmpv4Message::InformationReply {
|
|
identifier: BigEndian::read_u16(&bytes[4..6]),
|
|
sequence: BigEndian::read_u16(&bytes[6..8]),
|
|
},
|
|
13 => {
|
|
if packet_len < 20 {
|
|
return Err(PacketParseError::PacketTooSmall(bytes.len()));
|
|
}
|
|
Icmpv4Message::Timestamp {
|
|
identifier: BigEndian::read_u16(&bytes[4..6]),
|
|
sequence: BigEndian::read_u16(&bytes[6..8]),
|
|
originate: BigEndian::read_u32(&bytes[8..12]),
|
|
receive: BigEndian::read_u32(&bytes[12..16]),
|
|
transmit: BigEndian::read_u32(&bytes[16..20]),
|
|
}
|
|
}
|
|
14 => {
|
|
if packet_len < 20 {
|
|
return Err(PacketParseError::PacketTooSmall(bytes.len()));
|
|
}
|
|
Icmpv4Message::TimestampReply {
|
|
identifier: BigEndian::read_u16(&bytes[4..6]),
|
|
sequence: BigEndian::read_u16(&bytes[6..8]),
|
|
originate: BigEndian::read_u32(&bytes[8..12]),
|
|
receive: BigEndian::read_u32(&bytes[12..16]),
|
|
transmit: BigEndian::read_u32(&bytes[16..20]),
|
|
}
|
|
}
|
|
t => {
|
|
dbg!(bytes);
|
|
return Err(PacketParseError::UnrecognizedICMPType(t));
|
|
}
|
|
};
|
|
return Ok(Icmpv4Packet {
|
|
typ: typ,
|
|
code: code,
|
|
checksum: checksum,
|
|
message: message,
|
|
});
|
|
}
|
|
|
|
/// Get this packet serialized to bytes suitable for sending on the wire.
|
|
pub fn get_bytes(&self, with_checksum: bool) -> Vec<u8> {
|
|
let mut bytes = Vec::new();
|
|
bytes.push(self.typ);
|
|
bytes.push(self.code);
|
|
let mut buf = vec![0; 2];
|
|
BigEndian::write_u16(&mut buf, if with_checksum { self.checksum } else { 0 });
|
|
bytes.append(&mut buf);
|
|
bytes.append(&mut self.message.get_bytes());
|
|
return bytes;
|
|
}
|
|
|
|
/// Calculate the checksum for the packet given the provided source and destination
|
|
/// addresses.
|
|
pub fn calculate_checksum(&self) -> u16 {
|
|
// First sum the pseudo header
|
|
let mut sum = 0u32;
|
|
|
|
// Then sum the len of the message bytes and then the message bytes starting
|
|
// with the message type field and with the checksum field set to 0.
|
|
let bytes = self.get_bytes(false);
|
|
sum += sum_big_endian_words(&bytes);
|
|
|
|
// handle the carry
|
|
while sum >> 16 != 0 {
|
|
sum = (sum >> 16) + (sum & 0xFFFF);
|
|
}
|
|
!sum as u16
|
|
}
|
|
|
|
/// Populate the checksum field of this Packet.
|
|
pub fn with_checksum(mut self) -> Self {
|
|
self.checksum = self.calculate_checksum();
|
|
self
|
|
}
|
|
}
|
|
|
|
impl TryFrom<&[u8]> for Icmpv4Packet {
|
|
type Error = PacketParseError;
|
|
fn try_from(b: &[u8]) -> Result<Self, Self::Error> {
|
|
Icmpv4Packet::parse(b)
|
|
}
|
|
}
|
|
|
|
impl WithEchoRequest for Icmpv4Packet {
|
|
type Packet = Icmpv4Packet;
|
|
|
|
fn with_echo_request(
|
|
identifier: u16,
|
|
sequence: u16,
|
|
payload: Vec<u8>,
|
|
) -> Result<Self::Packet, IcmpPacketBuildError> {
|
|
Ok(Self {
|
|
typ: 8,
|
|
code: 0,
|
|
checksum: 0,
|
|
message: Icmpv4Message::Echo {
|
|
identifier,
|
|
sequence,
|
|
payload,
|
|
},
|
|
})
|
|
}
|
|
}
|
|
|
|
impl WithUnreachable for Icmpv4Packet {
|
|
type Packet = Icmpv4Packet;
|
|
|
|
fn with_unreachable(code: u8, packet: Vec<u8>) -> Result<Self::Packet, IcmpPacketBuildError> {
|
|
if code > 5 {
|
|
return Err(IcmpPacketBuildError::InvalidCode(code));
|
|
}
|
|
Ok(Self {
|
|
typ: 3,
|
|
code: code,
|
|
checksum: 0,
|
|
message: Icmpv4Message::Unreachable {
|
|
padding: 0,
|
|
header: packet,
|
|
},
|
|
})
|
|
}
|
|
}
|
|
|
|
impl WithParameterProblem for Icmpv4Packet {
|
|
type Packet = Icmpv4Packet;
|
|
type Pointer = u8;
|
|
|
|
fn with_parameter_problem(
|
|
code: u8,
|
|
pointer: Self::Pointer,
|
|
packet: Vec<u8>,
|
|
) -> Result<Self::Packet, IcmpPacketBuildError> {
|
|
if code != 0 {
|
|
return Err(IcmpPacketBuildError::InvalidCode(code));
|
|
}
|
|
Ok(Self {
|
|
typ: 12,
|
|
code: code,
|
|
checksum: 0,
|
|
message: Icmpv4Message::ParameterProblem {
|
|
pointer: pointer,
|
|
padding: (0, 0),
|
|
header: packet,
|
|
},
|
|
})
|
|
}
|
|
}
|
|
|
|
impl WithTimeExceeded for Icmpv4Packet {
|
|
type Packet = Icmpv4Packet;
|
|
|
|
fn with_time_exceeded(code: u8, packet: Vec<u8>) -> Result<Self::Packet, IcmpPacketBuildError> {
|
|
if code > 1 {
|
|
return Err(IcmpPacketBuildError::InvalidCode(code));
|
|
}
|
|
Ok(Self {
|
|
typ: 11,
|
|
code: code,
|
|
checksum: 0,
|
|
message: Icmpv4Message::TimeExceeded {
|
|
padding: 0,
|
|
header: packet,
|
|
},
|
|
})
|
|
}
|
|
}
|
|
|
|
#[cfg(test)]
|
|
mod tests {
|
|
use super::*;
|
|
|
|
#[test]
|
|
fn packet_construction_echo_request_test() {
|
|
let pkt = Icmpv6Packet::with_echo_request(42, 1, vec![1, 2, 3, 4]).unwrap();
|
|
assert_eq!(pkt.typ, 128);
|
|
assert_eq!(pkt.code, 0);
|
|
assert_eq!(
|
|
pkt.message,
|
|
EchoRequest {
|
|
identifier: 42,
|
|
sequence: 1,
|
|
payload: vec![1, 2, 3, 4],
|
|
}
|
|
);
|
|
}
|
|
|
|
#[test]
|
|
fn packet_construction_echo_reply_test() {
|
|
let pkt = Icmpv6Packet::with_echo_reply(42, 1, vec![1, 2, 3, 4]).unwrap();
|
|
assert_eq!(pkt.typ, 129);
|
|
assert_eq!(pkt.code, 0);
|
|
assert_eq!(
|
|
pkt.message,
|
|
EchoReply {
|
|
identifier: 42,
|
|
sequence: 1,
|
|
payload: vec![1, 2, 3, 4],
|
|
}
|
|
);
|
|
}
|
|
|
|
#[test]
|
|
fn packet_construction_too_big_test() {
|
|
let pkt = Icmpv6Packet::with_packet_too_big(3, vec![1, 2, 3, 4]).unwrap();
|
|
assert_eq!(pkt.typ, 2);
|
|
assert_eq!(pkt.code, 0);
|
|
assert_eq!(
|
|
pkt.message,
|
|
PacketTooBig {
|
|
mtu: 3,
|
|
invoking_packet: vec![1, 2, 3, 4],
|
|
}
|
|
);
|
|
}
|
|
|
|
#[test]
|
|
fn packet_construction_time_exceeded() {
|
|
let pkt = Icmpv6Packet::with_time_exceeded(0, vec![1, 2, 3, 4]).unwrap();
|
|
assert_eq!(pkt.typ, 3);
|
|
assert_eq!(pkt.code, 0);
|
|
assert_eq!(
|
|
pkt.message,
|
|
TimeExceeded {
|
|
_unused: 0,
|
|
invoking_packet: vec![1, 2, 3, 4],
|
|
}
|
|
);
|
|
}
|
|
|
|
#[test]
|
|
fn packet_construction_time_exceeded_invalid_code() {
|
|
let pkt = Icmpv6Packet::with_time_exceeded(2, vec![1, 2, 3, 4]);
|
|
assert!(pkt.is_err());
|
|
let e = pkt.unwrap_err();
|
|
assert_eq!(e, IcmpPacketBuildError::InvalidCode(2));
|
|
}
|
|
|
|
#[test]
|
|
fn packet_construction_parameter_problem() {
|
|
let pkt = Icmpv6Packet::with_parameter_problem(0, 30, vec![1, 2, 3, 4, 5, 6, 7, 8, 9, 10])
|
|
.unwrap();
|
|
assert_eq!(pkt.typ, 4);
|
|
assert_eq!(pkt.code, 0);
|
|
assert_eq!(
|
|
pkt.message,
|
|
ParameterProblem {
|
|
pointer: 30,
|
|
invoking_packet: vec![1, 2, 3, 4, 5, 6, 7, 8, 9, 10],
|
|
}
|
|
);
|
|
}
|
|
|
|
#[test]
|
|
fn packet_construction_parameter_problem_invalid_code() {
|
|
let pkt = Icmpv6Packet::with_parameter_problem(3, 30, vec![1, 2, 3, 4]);
|
|
assert!(pkt.is_err());
|
|
let e = pkt.unwrap_err();
|
|
assert_eq!(e, IcmpPacketBuildError::InvalidCode(3));
|
|
}
|
|
|
|
#[test]
|
|
fn echo_packet_parse_test() {
|
|
// NOTE(jwall): I am shamelessly ripping ff the cases for this from libpnet
|
|
// The equivalent of your typical ping -6 ::1%lo
|
|
let lo = &Ipv6Addr::new(0, 0, 0, 0, 0, 0, 0, 1);
|
|
let mut data = vec![
|
|
0x80, // Icmpv6 Type
|
|
0x00, // Code
|
|
0xff, 0xff, // Checksum
|
|
0x00, 0x00, // Id
|
|
0x00, 0x01, // Sequence
|
|
// 56 bytes of "random" data
|
|
0x20, 0x20, 0x75, 0x73, 0x74, 0x20, 0x61, 0x20, 0x66, 0x6c, 0x65, 0x73, 0x68, 0x20,
|
|
0x77, 0x6f, 0x75, 0x6e, 0x64, 0x20, 0x20, 0x74, 0x69, 0x73, 0x20, 0x62, 0x75, 0x74,
|
|
0x20, 0x61, 0x20, 0x73, 0x63, 0x72, 0x61, 0x74, 0x63, 0x68, 0x20, 0x20, 0x6b, 0x6e,
|
|
0x69, 0x67, 0x68, 0x74, 0x73, 0x20, 0x6f, 0x66, 0x20, 0x6e, 0x69, 0x20, 0x20, 0x20,
|
|
];
|
|
let mut pkt = Icmpv6Packet::parse(&data).unwrap();
|
|
assert_eq!(pkt.typ, 128);
|
|
assert_eq!(pkt.code, 0x00);
|
|
if let EchoRequest {
|
|
identifier,
|
|
sequence,
|
|
payload,
|
|
} = &pkt.message
|
|
{
|
|
assert_eq!(*identifier, 0);
|
|
assert_eq!(*sequence, 1);
|
|
assert_eq!(
|
|
payload,
|
|
&[
|
|
0x20, 0x20, 0x75, 0x73, 0x74, 0x20, 0x61, 0x20, 0x66, 0x6c, 0x65, 0x73, 0x68,
|
|
0x20, 0x77, 0x6f, 0x75, 0x6e, 0x64, 0x20, 0x20, 0x74, 0x69, 0x73, 0x20, 0x62,
|
|
0x75, 0x74, 0x20, 0x61, 0x20, 0x73, 0x63, 0x72, 0x61, 0x74, 0x63, 0x68, 0x20,
|
|
0x20, 0x6b, 0x6e, 0x69, 0x67, 0x68, 0x74, 0x73, 0x20, 0x6f, 0x66, 0x20, 0x6e,
|
|
0x69, 0x20, 0x20, 0x20
|
|
]
|
|
);
|
|
} else {
|
|
assert!(
|
|
false,
|
|
"Packet did not parse as an EchoRequest {:?}",
|
|
pkt.message
|
|
);
|
|
}
|
|
assert_eq!(pkt.get_bytes(true), data);
|
|
assert_eq!(pkt.calculate_checksum(lo, lo), 0x1d2e);
|
|
pkt = pkt.with_checksum(lo, lo);
|
|
assert_eq!(pkt.checksum, 0x1d2e);
|
|
|
|
// Check echo response as well
|
|
data[0] = 0x81;
|
|
let pkt = Icmpv6Packet::parse(&data).unwrap();
|
|
assert_eq!(pkt.typ, 129);
|
|
assert_eq!(pkt.code, 0);
|
|
if let EchoReply {
|
|
identifier,
|
|
sequence,
|
|
payload,
|
|
} = &pkt.message
|
|
{
|
|
assert_eq!(*identifier, 0);
|
|
assert_eq!(*sequence, 1);
|
|
assert_eq!(
|
|
payload,
|
|
&[
|
|
0x20, 0x20, 0x75, 0x73, 0x74, 0x20, 0x61, 0x20, 0x66, 0x6c, 0x65, 0x73, 0x68,
|
|
0x20, 0x77, 0x6f, 0x75, 0x6e, 0x64, 0x20, 0x20, 0x74, 0x69, 0x73, 0x20, 0x62,
|
|
0x75, 0x74, 0x20, 0x61, 0x20, 0x73, 0x63, 0x72, 0x61, 0x74, 0x63, 0x68, 0x20,
|
|
0x20, 0x6b, 0x6e, 0x69, 0x67, 0x68, 0x74, 0x73, 0x20, 0x6f, 0x66, 0x20, 0x6e,
|
|
0x69, 0x20, 0x20, 0x20
|
|
]
|
|
);
|
|
} else {
|
|
assert!(
|
|
false,
|
|
"Packet did not parse as an EchoReply {:?}",
|
|
pkt.message
|
|
);
|
|
}
|
|
assert_eq!(pkt.get_bytes(true), data);
|
|
assert_eq!(pkt.calculate_checksum(lo, lo), 0x1c2e);
|
|
}
|
|
}
|