Fix ICMPv6 checksum function

The ICMPv6 checksum calculation requires the pseudo header.

Closes: #196
Approved by: whitequark
This commit is contained in:
Dan Robertson 2018-04-21 00:23:48 +00:00 committed by Homu
parent 6067607442
commit 010e55beed
3 changed files with 52 additions and 30 deletions

View File

@ -735,12 +735,13 @@ impl<'b, 'c> InterfaceInner<'b, 'c> {
}
#[cfg(feature = "proto-ipv6")]
fn process_icmpv6<'frame>(&self, _sockets: &mut SocketSet, ip_repr: IpRepr,
ip_payload: &'frame [u8]) -> Result<Packet<'frame>>
fn process_icmpv6<'frame>(&mut self, _sockets: &mut SocketSet,
ip_repr: IpRepr, ip_payload: &'frame [u8]) -> Result<Packet<'frame>>
{
let icmp_packet = Icmpv6Packet::new_checked(ip_payload)?;
let checksum_caps = self.device_capabilities.checksum.clone();
let icmp_repr = Icmpv6Repr::parse(&icmp_packet, &checksum_caps)?;
let icmp_repr = Icmpv6Repr::parse(&ip_repr.src_addr(), &ip_repr.dst_addr(),
&icmp_packet, &checksum_caps)?;
match icmp_repr {
// Respond to echo requests.
@ -971,8 +972,9 @@ impl<'b, 'c> InterfaceInner<'b, 'c> {
#[cfg(feature = "proto-ipv6")]
Packet::Icmpv6((ipv6_repr, icmpv6_repr)) => {
self.dispatch_ip(tx_token, timestamp, IpRepr::Ipv6(ipv6_repr),
|_ip_repr, payload| {
icmpv6_repr.emit(&mut Icmpv6Packet::new(payload), &checksum_caps);
|ip_repr, payload| {
icmpv6_repr.emit(&ip_repr.src_addr(), &ip_repr.dst_addr(),
&mut Icmpv6Packet::new(payload), &checksum_caps);
})
}
#[cfg(feature = "socket-raw")]

View File

@ -4,7 +4,7 @@ use byteorder::{ByteOrder, NetworkEndian};
use {Error, Result};
use phy::ChecksumCapabilities;
use super::ip::checksum;
use super::{Ipv6Packet, Ipv6Repr};
use super::{IpAddress, IpProtocol, Ipv6Packet, Ipv6Repr};
use super::NdiscRepr;
enum_with_unknown! {
@ -337,11 +337,15 @@ impl<T: AsRef<[u8]>> Packet<T> {
///
/// # Fuzzing
/// This function always returns `true` when fuzzing.
pub fn verify_checksum(&self) -> bool {
pub fn verify_checksum(&self, src_addr: &IpAddress, dst_addr: &IpAddress) -> bool {
if cfg!(fuzzing) { return true }
let data = self.buffer.as_ref();
checksum::data(data) == !0
checksum::combine(&[
checksum::pseudo_header(src_addr, dst_addr, IpProtocol::Icmpv6,
data.len() as u32),
checksum::data(data)
]) == !0
}
}
@ -417,11 +421,15 @@ impl<T: AsRef<[u8]> + AsMut<[u8]>> Packet<T> {
}
/// Compute and fill in the header checksum.
pub fn fill_checksum(&mut self) {
pub fn fill_checksum(&mut self, src_addr: &IpAddress, dst_addr: &IpAddress) {
self.set_checksum(0);
let checksum = {
let data = self.buffer.as_ref();
!checksum::data(data)
!checksum::combine(&[
checksum::pseudo_header(src_addr, dst_addr, IpProtocol::Icmpv6,
data.len() as u32),
checksum::data(data)
])
};
self.set_checksum(checksum)
}
@ -483,7 +491,8 @@ pub enum Repr<'a> {
impl<'a> Repr<'a> {
/// Parse an Internet Control Message Protocol version 6 packet and return
/// a high-level representation.
pub fn parse<T>(packet: &Packet<&'a T>, checksum_caps: &ChecksumCapabilities)
pub fn parse<T>(src_addr: &IpAddress, dst_addr: &IpAddress,
packet: &Packet<&'a T>, checksum_caps: &ChecksumCapabilities)
-> Result<Repr<'a>>
where T: AsRef<[u8]> + ?Sized {
fn create_packet_from_payload<'a, T>(packet: &Packet<&'a T>)
@ -503,7 +512,9 @@ impl<'a> Repr<'a> {
Ok((payload, repr))
}
// Valid checksum is expected.
if checksum_caps.icmpv6.rx() && !packet.verify_checksum() { return Err(Error::Checksum) }
if checksum_caps.icmpv6.rx() && !packet.verify_checksum(src_addr, dst_addr) {
return Err(Error::Checksum)
}
match (packet.msg_type(), packet.msg_code()) {
(Message::DstUnreachable, code) => {
@ -580,7 +591,8 @@ impl<'a> Repr<'a> {
/// Emit a high-level representation into an Internet Control Message Protocol version 6
/// packet.
pub fn emit<T>(&self, packet: &mut Packet<&mut T>, checksum_caps: &ChecksumCapabilities)
pub fn emit<T>(&self, src_addr: &IpAddress, dst_addr: &IpAddress,
packet: &mut Packet<&mut T>, checksum_caps: &ChecksumCapabilities)
where T: AsRef<[u8]> + AsMut<[u8]> + ?Sized {
fn emit_contained_packet(buffer: &mut [u8], header: Ipv6Repr, data: &[u8]) {
let mut ip_packet = Ipv6Packet::new(buffer);
@ -646,7 +658,7 @@ impl<'a> Repr<'a> {
}
if checksum_caps.icmpv6.tx() {
packet.fill_checksum()
packet.fill_checksum(src_addr, dst_addr);
} else {
// make sure we get a consistently zeroed checksum, since implementations might rely on it
packet.set_checksum(0);
@ -657,10 +669,11 @@ impl<'a> Repr<'a> {
#[cfg(test)]
mod test {
use wire::{Ipv6Address, Ipv6Repr, IpProtocol};
use wire::ip::test::{MOCK_IP_ADDR_1, MOCK_IP_ADDR_2};
use super::*;
static ECHO_PACKET_BYTES: [u8; 12] =
[0x80, 0x00, 0x16, 0xfe,
[0x80, 0x00, 0x19, 0xb3,
0x12, 0x34, 0xab, 0xcd,
0xaa, 0x00, 0x00, 0xff];
@ -668,7 +681,7 @@ mod test {
[0xaa, 0x00, 0x00, 0xff];
static PKT_TOO_BIG_BYTES: [u8; 60] =
[0x02, 0x00, 0x0d, 0x44,
[0x02, 0x00, 0x0f, 0xc9,
0x00, 0x00, 0x05, 0xdc,
0x60, 0x00, 0x00, 0x00,
0x00, 0x0c, 0x11, 0x40,
@ -737,11 +750,11 @@ mod test {
let packet = Packet::new(&ECHO_PACKET_BYTES[..]);
assert_eq!(packet.msg_type(), Message::EchoRequest);
assert_eq!(packet.msg_code(), 0);
assert_eq!(packet.checksum(), 0x16fe);
assert_eq!(packet.checksum(), 0x19b3);
assert_eq!(packet.echo_ident(), 0x1234);
assert_eq!(packet.echo_seq_no(), 0xabcd);
assert_eq!(packet.payload(), &ECHO_PACKET_PAYLOAD[..]);
assert_eq!(packet.verify_checksum(), true);
assert_eq!(packet.verify_checksum(&MOCK_IP_ADDR_1, &MOCK_IP_ADDR_2), true);
assert!(!packet.msg_type().is_error());
}
@ -754,14 +767,15 @@ mod test {
packet.set_echo_ident(0x1234);
packet.set_echo_seq_no(0xabcd);
packet.payload_mut().copy_from_slice(&ECHO_PACKET_PAYLOAD[..]);
packet.fill_checksum();
packet.fill_checksum(&MOCK_IP_ADDR_1, &MOCK_IP_ADDR_2);
assert_eq!(&packet.into_inner()[..], &ECHO_PACKET_BYTES[..]);
}
#[test]
fn test_echo_repr_parse() {
let packet = Packet::new(&ECHO_PACKET_BYTES[..]);
let repr = Repr::parse(&packet, &ChecksumCapabilities::default()).unwrap();
let repr = Repr::parse(&MOCK_IP_ADDR_1, &MOCK_IP_ADDR_2,
&packet, &ChecksumCapabilities::default()).unwrap();
assert_eq!(repr, echo_packet_repr());
}
@ -770,7 +784,8 @@ mod test {
let repr = echo_packet_repr();
let mut bytes = vec![0xa5; repr.buffer_len()];
let mut packet = Packet::new(&mut bytes);
repr.emit(&mut packet, &ChecksumCapabilities::default());
repr.emit(&MOCK_IP_ADDR_1, &MOCK_IP_ADDR_2,
&mut packet, &ChecksumCapabilities::default());
assert_eq!(&packet.into_inner()[..], &ECHO_PACKET_BYTES[..]);
}
@ -779,10 +794,10 @@ mod test {
let packet = Packet::new(&PKT_TOO_BIG_BYTES[..]);
assert_eq!(packet.msg_type(), Message::PktTooBig);
assert_eq!(packet.msg_code(), 0);
assert_eq!(packet.checksum(), 0x0d44);
assert_eq!(packet.checksum(), 0x0fc9);
assert_eq!(packet.pkt_too_big_mtu(), 1500);
assert_eq!(packet.payload(), &PKT_TOO_BIG_IP_PAYLOAD[..]);
assert_eq!(packet.verify_checksum(), true);
assert_eq!(packet.verify_checksum(&MOCK_IP_ADDR_1, &MOCK_IP_ADDR_2), true);
assert!(packet.msg_type().is_error());
}
@ -794,14 +809,15 @@ mod test {
packet.set_msg_code(0);
packet.set_pkt_too_big_mtu(1500);
packet.payload_mut().copy_from_slice(&PKT_TOO_BIG_IP_PAYLOAD[..]);
packet.fill_checksum();
packet.fill_checksum(&MOCK_IP_ADDR_1, &MOCK_IP_ADDR_2);
assert_eq!(&packet.into_inner()[..], &PKT_TOO_BIG_BYTES[..]);
}
#[test]
fn test_too_big_repr_parse() {
let packet = Packet::new(&PKT_TOO_BIG_BYTES[..]);
let repr = Repr::parse(&packet, &ChecksumCapabilities::default()).unwrap();
let repr = Repr::parse(&MOCK_IP_ADDR_1, &MOCK_IP_ADDR_2,
&packet, &ChecksumCapabilities::default()).unwrap();
assert_eq!(repr, too_big_packet_repr());
}
@ -810,7 +826,8 @@ mod test {
let repr = too_big_packet_repr();
let mut bytes = vec![0xa5; repr.buffer_len()];
let mut packet = Packet::new(&mut bytes);
repr.emit(&mut packet, &ChecksumCapabilities::default());
repr.emit(&MOCK_IP_ADDR_1, &MOCK_IP_ADDR_2,
&mut packet, &ChecksumCapabilities::default());
assert_eq!(&packet.into_inner()[..], &PKT_TOO_BIG_BYTES[..]);
}
}

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@ -454,9 +454,10 @@ mod test {
use phy::ChecksumCapabilities;
use super::*;
use wire::Icmpv6Repr;
use wire::ip::test::{MOCK_IP_ADDR_1, MOCK_IP_ADDR_2};
static ROUTER_ADVERT_BYTES: [u8; 24] =
[0x86, 0x00, 0xa7, 0x35,
[0x86, 0x00, 0xa9, 0xde,
0x40, 0x80, 0x03, 0x84,
0x00, 0x00, 0x03, 0x84,
0x00, 0x00, 0x03, 0x84,
@ -504,14 +505,15 @@ mod test {
packet.set_reachable_time(Duration::from_millis(900));
packet.set_retrans_time(Duration::from_millis(900));
packet.payload_mut().copy_from_slice(&SOURCE_LINK_LAYER_OPT[..]);
packet.fill_checksum();
packet.fill_checksum(&MOCK_IP_ADDR_1, &MOCK_IP_ADDR_2);
assert_eq!(&packet.into_inner()[..], &ROUTER_ADVERT_BYTES[..]);
}
#[test]
fn test_router_advert_repr_parse() {
let packet = Packet::new(&ROUTER_ADVERT_BYTES[..]);
assert_eq!(Icmpv6Repr::parse(&packet, &ChecksumCapabilities::default()).unwrap(),
assert_eq!(Icmpv6Repr::parse(&MOCK_IP_ADDR_1, &MOCK_IP_ADDR_2,
&packet, &ChecksumCapabilities::default()).unwrap(),
create_repr());
}
@ -519,7 +521,8 @@ mod test {
fn test_router_advert_repr_emit() {
let mut bytes = vec![0x2a; 24];
let mut packet = Packet::new(&mut bytes[..]);
create_repr().emit(&mut packet, &ChecksumCapabilities::default());
create_repr().emit(&MOCK_IP_ADDR_1, &MOCK_IP_ADDR_2,
&mut packet, &ChecksumCapabilities::default());
assert_eq!(&packet.into_inner()[..], &ROUTER_ADVERT_BYTES[..]);
}
}