Add structured ICMPv6 ND payload and option slice support

etherparse/src/transport/icmpv4_header.rs

@@ -385,7 +385,7 @@ mod test {
         fn read(
             non_timestamp_type in any::<u8>().prop_filter(
                 "type must be a non timestamp type",
-                |v| (*v != icmpv4::TYPE_TIMESTAMP_REPLY && *v != icmpv4::TYPE_TIMESTAMP)
+                |v| *v != icmpv4::TYPE_TIMESTAMP_REPLY && *v != icmpv4::TYPE_TIMESTAMP
             ),
             non_zero_code in 1u8..=u8::MAX,
             bytes in any::<[u8;icmpv4::TimestampMessage::LEN]>()

etherparse/src/transport/icmpv6/icmpv6_payload/mod.rs

@@ -0,0 +1,122 @@
+mod neighbor_advertisement_payload;
+pub use neighbor_advertisement_payload::*;
+
+mod neighbor_solicitation_payload;
+pub use neighbor_solicitation_payload::*;
+
+mod redirect_payload;
+pub use redirect_payload::*;
+
+mod router_advertisement_payload;
+pub use router_advertisement_payload::*;
+
+mod router_solicitation_payload;
+pub use router_solicitation_payload::*;
+
+/// Owned, structured payload data that follows the first 8 bytes of an ICMPv6 packet.
+#[derive(Clone, Debug, Eq, PartialEq)]
+#[non_exhaustive]
+pub enum Icmpv6Payload {
+    /// Payload of a Router Solicitation message.
+    RouterSolicitation(RouterSolicitationPayload),
+    /// Payload of a Router Advertisement message.
+    RouterAdvertisement(RouterAdvertisementPayload),
+    /// Payload of a Neighbor Solicitation message.
+    NeighborSolicitation(NeighborSolicitationPayload),
+    /// Payload of a Neighbor Advertisement message.
+    NeighborAdvertisement(NeighborAdvertisementPayload),
+    /// Payload of a Redirect message.
+    Redirect(RedirectPayload),
+}
+
+impl Icmpv6Payload {
+    /// Returns the serialized payload length in bytes.
+    pub fn len(&self) -> usize {
+        use Icmpv6Payload::*;
+        match self {
+            RouterSolicitation(_) => RouterSolicitationPayload::LEN,
+            RouterAdvertisement(_) => RouterAdvertisementPayload::LEN,
+            NeighborSolicitation(_) => NeighborSolicitationPayload::LEN,
+            NeighborAdvertisement(_) => NeighborAdvertisementPayload::LEN,
+            Redirect(_) => RedirectPayload::LEN,
+        }
+    }
+
+    /// Write the fixed payload bytes to the writer.
+    #[cfg(feature = "std")]
+    #[cfg_attr(docsrs, doc(cfg(feature = "std")))]
+    pub fn write<T: std::io::Write + Sized>(
+        &self,
+        writer: &mut T,
+    ) -> Result<(), std::io::Error> {
+        match self {
+            Icmpv6Payload::RouterSolicitation(value) => writer.write_all(&value.to_bytes()),
+            Icmpv6Payload::RouterAdvertisement(value) => writer.write_all(&value.to_bytes()),
+            Icmpv6Payload::NeighborSolicitation(value) => writer.write_all(&value.to_bytes()),
+            Icmpv6Payload::NeighborAdvertisement(value) => writer.write_all(&value.to_bytes()),
+            Icmpv6Payload::Redirect(value) => writer.write_all(&value.to_bytes()),
+        }
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use alloc::format;
+    use proptest::prelude::*;
+
+    #[test]
+    fn router_solicitation_payload_to_bytes() {
+        assert_eq!([] as [u8; 0], RouterSolicitationPayload.to_bytes());
+    }
+
+    proptest! {
+        #[test]
+        fn payloads_to_bytes(
+            reachable_time in any::<u32>(),
+            retrans_timer in any::<u32>(),
+            target_address in any::<[u8;16]>(),
+            destination_address in any::<[u8;16]>()
+        ) {
+            let reachable_time_be = reachable_time.to_be_bytes();
+            let retrans_timer_be = retrans_timer.to_be_bytes();
+            let mut expected_router_advertisement = [0u8; RouterAdvertisementPayload::LEN];
+            expected_router_advertisement[..4].copy_from_slice(&reachable_time_be);
+            expected_router_advertisement[4..].copy_from_slice(&retrans_timer_be);
+
+            let mut expected_redirect = [0u8; RedirectPayload::LEN];
+            expected_redirect[..16].copy_from_slice(&target_address);
+            expected_redirect[16..].copy_from_slice(&destination_address);
+
+            assert_eq!(
+                RouterAdvertisementPayload {
+                    reachable_time,
+                    retrans_timer,
+                }.to_bytes(),
+                expected_router_advertisement
+            );
+            assert_eq!(
+                NeighborSolicitationPayload {
+                    target_address: core::net::Ipv6Addr::from(target_address),
+                }
+                .to_bytes(),
+                target_address
+            );
+            assert_eq!(
+                NeighborAdvertisementPayload {
+                    target_address: core::net::Ipv6Addr::from(target_address),
+                }
+                .to_bytes(),
+                target_address
+            );
+            assert_eq!(
+                RedirectPayload {
+                    target_address: core::net::Ipv6Addr::from(target_address),
+                    destination_address: core::net::Ipv6Addr::from(destination_address),
+                }
+                .to_bytes(),
+                expected_redirect
+            );
+        }
+    }
+}

etherparse/src/transport/icmpv6/icmpv6_payload/neighbor_advertisement_payload.rs

@@ -0,0 +1,44 @@
+use core::net::Ipv6Addr;
+
+/// Owned payload of a Neighbor Advertisement message (RFC 4861, Section 4.4).
+///
+/// The full packet layout is:
+/// ```text
+///  0                   1                   2                   3
+///  0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+/// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+/// |     Type      |     Code      |          Checksum             |
+/// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+/// |R|S|O|                     Reserved                            |
+/// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+/// |                                                               |
+/// +                                                               +
+/// |                                                               |
+/// +                       Target Address                          +
+/// |                                                               |
+/// +                                                               +
+/// |                                                               |
+/// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+/// |   Options ...
+/// +-+-+-+-+-+-+-+-+-+-+-+-
+/// ```
+///
+/// In this crate, `R`, `S`, and `O` are represented by
+/// [`crate::icmpv6::NeighborAdvertisementHeader`] in
+/// [`crate::Icmpv6Type::NeighborAdvertisement`]. This payload struct represents
+/// the fixed `Target Address` bytes.
+#[derive(Clone, Copy, Debug, Eq, PartialEq, Ord, PartialOrd, Hash)]
+pub struct NeighborAdvertisementPayload {
+    /// Target IPv6 address.
+    pub target_address: Ipv6Addr,
+}
+
+impl NeighborAdvertisementPayload {
+    /// Fixed payload length in bytes after the ICMPv6 header.
+    pub const LEN: usize = 16;
+
+    /// Convert to on-the-wire bytes.
+    pub const fn to_bytes(&self) -> [u8; Self::LEN] {
+        self.target_address.octets()
+    }
+}

etherparse/src/transport/icmpv6/icmpv6_payload/neighbor_solicitation_payload.rs

@@ -0,0 +1,43 @@
+use core::net::Ipv6Addr;
+
+/// Owned payload of a Neighbor Solicitation message (RFC 4861, Section 4.3).
+///
+/// The full packet layout is:
+/// ```text
+///  0                   1                   2                   3
+///  0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+/// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+/// |     Type      |     Code      |          Checksum             |
+/// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+/// |                           Reserved                            |
+/// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+/// |                                                               |
+/// +                                                               +
+/// |                                                               |
+/// +                       Target Address                          +
+/// |                                                               |
+/// +                                                               +
+/// |                                                               |
+/// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+/// |   Options ...
+/// +-+-+-+-+-+-+-+-+-+-+-+-
+/// ```
+///
+/// In this crate, the first 8 bytes (including `Reserved`) are represented by
+/// [`crate::Icmpv6Type::NeighborSolicitation`]. This payload struct represents
+/// the fixed `Target Address` bytes.
+#[derive(Clone, Copy, Debug, Eq, PartialEq, Ord, PartialOrd, Hash)]
+pub struct NeighborSolicitationPayload {
+    /// Target IPv6 address.
+    pub target_address: Ipv6Addr,
+}
+
+impl NeighborSolicitationPayload {
+    /// Fixed payload length in bytes after the ICMPv6 header.
+    pub const LEN: usize = 16;
+
+    /// Convert to on-the-wire bytes.
+    pub const fn to_bytes(&self) -> [u8; Self::LEN] {
+        self.target_address.octets()
+    }
+}

etherparse/src/transport/icmpv6/icmpv6_payload/redirect_payload.rs

@@ -0,0 +1,59 @@
+use core::net::Ipv6Addr;
+
+/// Owned payload of a Redirect message (RFC 4861, Section 4.5).
+///
+/// The full packet layout is:
+/// ```text
+///  0                   1                   2                   3
+///  0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+/// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+/// |     Type      |     Code      |          Checksum             |
+/// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+/// |                           Reserved                            |
+/// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+/// |                                                               |
+/// +                                                               +
+/// |                                                               |
+/// +                       Target Address                          +
+/// |                                                               |
+/// +                                                               +
+/// |                                                               |
+/// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+/// |                                                               |
+/// +                                                               +
+/// |                                                               |
+/// +                     Destination Address                       +
+/// |                                                               |
+/// +                                                               +
+/// |                                                               |
+/// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+/// |   Options ...
+/// +-+-+-+-+-+-+-+-+-+-+-+-
+/// ```
+///
+/// In this crate, the first 8 bytes (including `Reserved`) are represented by
+/// [`crate::Icmpv6Type::Redirect`]. This payload struct represents the fixed bytes:
+/// - `Target Address`
+/// - `Destination Address`
+#[derive(Clone, Copy, Debug, Eq, PartialEq, Ord, PartialOrd, Hash)]
+pub struct RedirectPayload {
+    /// Better first-hop target address.
+    pub target_address: Ipv6Addr,
+    /// Destination address being redirected.
+    pub destination_address: Ipv6Addr,
+}
+
+impl RedirectPayload {
+    /// Fixed payload length in bytes after the ICMPv6 header.
+    pub const LEN: usize = 32;
+
+    /// Convert to on-the-wire bytes.
+    pub const fn to_bytes(&self) -> [u8; Self::LEN] {
+        let mut out = [0u8; Self::LEN];
+        // Safety: unwraps are safe because Self::LEN == 32, which is larger than the number of
+        // octets in IPv6 address
+        *out.first_chunk_mut().unwrap() = self.target_address.octets();
+        *out.last_chunk_mut().unwrap() = self.destination_address.octets();
+        out
+    }
+}

etherparse/src/transport/icmpv6/icmpv6_payload/router_advertisement_payload.rs

@@ -0,0 +1,48 @@
+/// Owned payload of a Router Advertisement message (RFC 4861, Section 4.2).
+///
+/// The full packet layout is:
+/// ```text
+///  0                   1                   2                   3
+///  0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+/// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+/// |     Type      |     Code      |          Checksum             |
+/// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+/// | Cur Hop Limit |M|O|  Reserved |       Router Lifetime         |
+/// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+/// |                         Reachable Time                        |
+/// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+/// |                          Retrans Timer                        |
+/// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+/// |   Options ...
+/// +-+-+-+-+-+-+-+-+-+-+-+-
+/// ```
+///
+/// In this crate, `Cur Hop Limit`, `M`, `O`, and `Router Lifetime` are represented by
+/// [`crate::icmpv6::RouterAdvertisementHeader`] in [`crate::Icmpv6Type::RouterAdvertisement`].
+/// This payload struct represents the fixed bytes after that:
+/// - `Reachable Time`
+/// - `Retrans Timer`
+#[derive(Clone, Copy, Debug, Eq, PartialEq, Ord, PartialOrd, Hash)]
+pub struct RouterAdvertisementPayload {
+    /// Reachable time in milliseconds.
+    pub reachable_time: u32,
+    /// Retransmit timer in milliseconds.
+    pub retrans_timer: u32,
+}
+
+impl RouterAdvertisementPayload {
+    /// Fixed payload length in bytes after the ICMPv6 header.
+    pub const LEN: usize = 8;
+
+    /// Convert to on-the-wire bytes.
+    pub fn to_bytes(&self) -> [u8; Self::LEN] {
+        let mut out = [0u8; Self::LEN];
+
+        // Safety: unwraps are safe because Self::LEN == 8, which is larger than the number of
+        // octets in u32
+        *out.first_chunk_mut().unwrap() = self.reachable_time.to_be_bytes();
+        *out.last_chunk_mut().unwrap() = self.retrans_timer.to_be_bytes();
+
+        out
+    }
+}

etherparse/src/transport/icmpv6/icmpv6_payload/router_solicitation_payload.rs

@@ -0,0 +1,29 @@
+/// Owned payload of a Router Solicitation message (RFC 4861, Section 4.1).
+///
+/// The full packet layout is:
+/// ```text
+///  0                   1                   2                   3
+///  0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+/// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+/// |     Type      |     Code      |          Checksum             |
+/// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+/// |                            Reserved                           |
+/// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+/// |   Options ...
+/// +-+-+-+-+-+-+-+-+-+-+-+-
+/// ```
+///
+/// In this crate, the first 8 bytes (including `Reserved`) are represented by
+/// [`crate::Icmpv6Type::RouterSolicitation`], so this payload struct has no fixed bytes.
+#[derive(Clone, Copy, Debug, Default, Eq, PartialEq, Ord, PartialOrd, Hash)]
+pub struct RouterSolicitationPayload;
+
+impl RouterSolicitationPayload {
+    /// Fixed payload length in bytes after the ICMPv6 header.
+    pub const LEN: usize = 0;
+
+    /// Convert to on-the-wire bytes.
+    pub const fn to_bytes(&self) -> [u8; Self::LEN] {
+        []
+    }
+}