SRv6 and Nexthop Group support

src/lib.rs

@@ -4,6 +4,7 @@ pub mod address;
 pub mod link;
 pub mod neighbour;
 pub mod neighbour_table;
+pub mod nexthop;
 pub mod nsid;
 pub mod prefix;
 pub mod route;

src/link/af_spec/inet6_icmp.rs

@@ -5,7 +5,7 @@ use netlink_packet_utils::{
     DecodeError,
 };
 
-pub(crate) const ICMP6_STATS_LEN: usize = 48;
+pub(crate) const ICMP6_STATS_LEN: usize = 56;
 
 #[derive(Clone, Copy, Eq, PartialEq, Debug, Default)]
 #[non_exhaustive]

src/link/af_spec/inet6_stats.rs

@@ -5,7 +5,7 @@ use netlink_packet_utils::{
     DecodeError,
 };
 
-pub(crate) const INET6_STATS_LEN: usize = 288;
+pub(crate) const INET6_STATS_LEN: usize = 304;
 
 buffer!(Inet6StatsBuffer(INET6_STATS_LEN) {
     num: (i64, 0..8),

src/message.rs

@@ -8,6 +8,7 @@ use netlink_packet_utils::{
     DecodeError, Emitable, Parseable, ParseableParametrized,
 };
 
+use crate::nexthop::{NexthopMessage, NexthopMessageBuffer};
 use crate::tc::{TcActionMessage, TcActionMessageBuffer};
 use crate::{
     address::{AddressHeader, AddressMessage, AddressMessageBuffer},
@@ -76,6 +77,9 @@ const RTM_GETNSID: u16 = 90;
 const RTM_NEWCHAIN: u16 = 100;
 const RTM_DELCHAIN: u16 = 101;
 const RTM_GETCHAIN: u16 = 102;
+const RTM_NEWNEXTHOP: u16 = 104;
+const RTM_DELNEXTHOP: u16 = 105;
+const RTM_GETNEXTHOP: u16 = 106;
 const RTM_NEWLINKPROP: u16 = 108;
 const RTM_DELLINKPROP: u16 = 109;
 
@@ -322,6 +326,22 @@ impl<'a, T: AsRef<[u8]> + ?Sized>
                 }
             }
 
+            // Nexthop Messages
+            RTM_NEWNEXTHOP | RTM_DELNEXTHOP | RTM_GETNEXTHOP => {
+                let err = "invalid nexthop message";
+                let msg = NexthopMessage::parse(
+                    &NexthopMessageBuffer::new_checked(&buf.inner())
+                        .context(err)?,
+                )
+                .context(err)?;
+                match message_type {
+                    RTM_NEWNEXTHOP => RouteNetlinkMessage::NewNexthop(msg),
+                    RTM_DELNEXTHOP => RouteNetlinkMessage::DelNexthop(msg),
+                    RTM_GETNEXTHOP => RouteNetlinkMessage::GetNexthop(msg),
+                    _ => unreachable!(),
+                }
+            }
+
             _ => {
                 return Err(
                     format!("Unknown message type: {message_type}").into()
@@ -369,6 +389,9 @@ pub enum RouteNetlinkMessage {
     NewTrafficChain(TcMessage),
     DelTrafficChain(TcMessage),
     GetTrafficChain(TcMessage),
+    NewNexthop(NexthopMessage),
+    DelNexthop(NexthopMessage),
+    GetNexthop(NexthopMessage),
     NewNsId(NsidMessage),
     DelNsId(NsidMessage),
     GetNsId(NsidMessage),
@@ -526,6 +549,18 @@ impl RouteNetlinkMessage {
         matches!(self, RouteNetlinkMessage::DelRule(_))
     }
 
+    pub fn is_get_nexthop(&self) -> bool {
+        matches!(self, RouteNetlinkMessage::GetNexthop(_))
+    }
+
+    pub fn is_new_nexthop(&self) -> bool {
+        matches!(self, RouteNetlinkMessage::NewNexthop(_))
+    }
+
+    pub fn is_del_nexthop(&self) -> bool {
+        matches!(self, RouteNetlinkMessage::DelNexthop(_))
+    }
+
     pub fn message_type(&self) -> u16 {
         use self::RouteNetlinkMessage::*;
 
@@ -570,6 +605,9 @@ impl RouteNetlinkMessage {
             GetRule(_) => RTM_GETRULE,
             NewRule(_) => RTM_NEWRULE,
             DelRule(_) => RTM_DELRULE,
+            NewNexthop(_) => RTM_NEWNEXTHOP,
+            DelNexthop(_) => RTM_DELNEXTHOP,
+            GetNexthop(_) => RTM_GETNEXTHOP,
         }
     }
 }
@@ -637,7 +675,12 @@ impl Emitable for RouteNetlinkMessage {
             | DelTrafficAction(ref msg)
             | GetTrafficAction(ref msg)
             => msg.buffer_len(),
-        }
+
+            | NewNexthop(ref msg)
+            | DelNexthop(ref msg)
+            | GetNexthop(ref msg)
+            => msg.buffer_len(),
+}
     }
 
     #[rustfmt::skip]
@@ -702,7 +745,12 @@ impl Emitable for RouteNetlinkMessage {
             | DelTrafficAction(ref msg)
             | GetTrafficAction(ref msg)
             => msg.emit(buffer),
-        }
+
+            | NewNexthop(ref msg)
+            | DelNexthop(ref msg)
+            | GetNexthop(ref msg)
+            => msg.emit(buffer),
+}
     }
 }
 

src/nexthop/attribute.rs

@@ -0,0 +1,154 @@
+// SPDX-License-Identifier: MIT
+
+use anyhow::Context;
+use byteorder::{ByteOrder, NativeEndian};
+use netlink_packet_utils::{
+    nla::{DefaultNla, Nla, NlaBuffer, NLA_F_NESTED},
+    parsers::{parse_u16, parse_u32},
+    DecodeError, Emitable, Parseable, ParseableParametrized,
+};
+
+use crate::{
+    route::{RouteAddress, RouteLwTunnelEncap},
+    AddressFamily,
+};
+
+use super::NexthopGroup;
+
+const NHA_ID: u16 = 1;
+const NHA_GROUP: u16 = 2;
+const NHA_GROUP_TYPE: u16 = 3;
+const NHA_BLACKHOLE: u16 = 4;
+const NHA_OIF: u16 = 5;
+const NHA_GATEWAY: u16 = 6;
+const NHA_ENCAP_TYPE: u16 = 7;
+const NHA_ENCAP: u16 = 8;
+const NHA_GROUPS: u16 = 9;
+const NHA_MASTER: u16 = 10;
+const NHA_FDB: u16 = 11;
+// const NHA_RES_GROUP: u16 = 12;
+// const NHA_RES_BUCKET: u16 = 13;
+
+#[derive(Debug, PartialEq, Eq, Clone)]
+#[non_exhaustive]
+pub enum NexthopAttribute {
+    Id(u32),
+    Group(Vec<NexthopGroup>),
+    GroupType(u16),
+    Blackhole,
+    Oif(u32),
+    Gateway(RouteAddress),
+    EncapType(u16),
+    Encap(Vec<RouteLwTunnelEncap>),
+    Groups,
+    Master(u32),
+    Fdb,
+    Other(DefaultNla),
+}
+
+impl Nla for NexthopAttribute {
+    fn value_len(&self) -> usize {
+        match self {
+            Self::Id(_) | Self::Oif(_) | Self::Master(_) => 4,
+            Self::Group(groups) => {
+                groups.iter().map(|grp| grp.buffer_len()).sum()
+            }
+            Self::GroupType(_) | Self::EncapType(_) => 2,
+            Self::Blackhole | Self::Groups | Self::Fdb => 0,
+            Self::Encap(v) => v.as_slice().buffer_len(),
+            Self::Gateway(addr) => addr.buffer_len(),
+            Self::Other(attr) => attr.value_len(),
+        }
+    }
+
+    fn emit_value(&self, buffer: &mut [u8]) {
+        match self {
+            Self::Id(value) | Self::Oif(value) | Self::Master(value) => {
+                NativeEndian::write_u32(buffer, *value)
+            }
+            Self::Group(groups) => {
+                let mut offset = 0;
+                for grp in groups {
+                    let len = grp.buffer_len();
+                    grp.emit(&mut buffer[offset..offset + len]);
+                    offset += len
+                }
+            }
+            Self::GroupType(value) | Self::EncapType(value) => {
+                NativeEndian::write_u16(buffer, *value);
+            }
+            Self::Blackhole | Self::Groups | Self::Fdb => {}
+            Self::Encap(nlas) => nlas.as_slice().emit(buffer),
+            Self::Gateway(addr) => addr.emit(buffer),
+            Self::Other(attr) => attr.emit_value(buffer),
+        }
+    }
+
+    fn kind(&self) -> u16 {
+        match self {
+            Self::Id(_) => NHA_ID,
+            Self::Group(_) => NHA_GROUP,
+            Self::GroupType(_) => NHA_GROUP_TYPE,
+            Self::Blackhole => NHA_BLACKHOLE,
+            Self::Oif(_) => NHA_OIF,
+            Self::Gateway(_) => NHA_GATEWAY,
+            Self::EncapType(_) => NHA_ENCAP_TYPE,
+            Self::Encap(_) => NHA_ENCAP | NLA_F_NESTED,
+            Self::Groups => NHA_GROUPS,
+            Self::Master(_) => NHA_MASTER,
+            Self::Fdb => NHA_FDB,
+            Self::Other(nla) => nla.kind(),
+        }
+    }
+}
+
+impl<'a, T: AsRef<[u8]> + ?Sized>
+    ParseableParametrized<NlaBuffer<&'a T>, AddressFamily>
+    for NexthopAttribute
+{
+    fn parse_with_param(
+        buf: &NlaBuffer<&'a T>,
+        address_family: AddressFamily,
+    ) -> Result<Self, DecodeError> {
+        let payload = buf.value();
+        Ok(match buf.kind() {
+            NHA_ID => Self::Id(
+                parse_u32(payload).context(format!("invalid NHA_ID value"))?,
+            ),
+            NHA_GROUP => {
+                let mut groups = vec![];
+                let mut i: usize = 0;
+                while i + 8 <= payload.len() {
+                    groups.push(NexthopGroup::parse(&payload[i..i + 8])?);
+                    i += 8;
+                }
+                Self::Group(groups)
+            }
+            NHA_GROUP_TYPE => Self::GroupType(
+                parse_u16(payload)
+                    .context(format!("invalid NHA_GROUP_TYPE value"))?,
+            ),
+            NHA_BLACKHOLE => Self::Blackhole,
+            NHA_OIF => Self::Oif(
+                parse_u32(payload).context(format!("invalid NHA_OIF value"))?,
+            ),
+            NHA_GATEWAY => {
+                Self::Gateway(RouteAddress::parse(address_family, payload)?)
+            }
+            NHA_ENCAP_TYPE => Self::EncapType(
+                parse_u16(payload)
+                    .context(format!("invalid NHA_ENCAP_TYPE value"))?,
+            ),
+            NHA_GROUPS => Self::Groups,
+            NHA_MASTER => Self::Master(
+                parse_u32(payload)
+                    .context(format!("invalid NHA_MASTER value"))?,
+            ),
+            NHA_FDB => Self::Fdb,
+            _ => Self::Other(
+                DefaultNla::parse(buf)
+                    .context("invalid link NLA value (unknown type)")?,
+            ),
+        })
+    }
+}

src/nexthop/flags.rs

@@ -0,0 +1,26 @@
+// SPDX-License-Identifier: MIT
+
+const RTNH_F_DEAD: u32 = 1 << 0;
+const RTNH_F_PERVASIVE: u32 = 1 << 1;
+const RTNH_F_ONLINK: u32 = 1 << 2;
+const RTNH_F_OFFLOAD: u32 = 1 << 3;
+const RTNH_F_LINKDOWN: u32 = 1 << 4;
+const RTNH_F_UNRESOLVED: u32 = 1 << 5;
+const RTNH_F_TRAP: u32 = 1 << 6;
+// const RTNH_COMPARE_MASK: u32 =
+//     RTNH_F_DEAD | RTNH_F_LINKDOWN | RTNH_F_OFFLOAD | RTNH_F_TRAP;
+
+bitflags! {
+    #[derive(Clone, Eq, PartialEq, Debug, Copy, Default)]
+    #[non_exhaustive]
+    pub struct NexthopFlags: u32 {
+        const Dead = RTNH_F_DEAD;
+        const Pervasive = RTNH_F_PERVASIVE;
+        const Onlink = RTNH_F_ONLINK;
+        const Offload  = RTNH_F_OFFLOAD;
+        const Linkdown = RTNH_F_LINKDOWN;
+        const Unresolved = RTNH_F_UNRESOLVED;
+        const Trap= RTNH_F_TRAP;
+        const _ = !0;
+    }
+}

src/nexthop/group.rs

@@ -0,0 +1,43 @@
+use byteorder::{ByteOrder, NativeEndian};
+use netlink_packet_utils::{
+    parsers::{parse_u16, parse_u32},
+    DecodeError, Emitable,
+};
+
+#[derive(Debug, PartialEq, Eq, Clone, Copy, Default)]
+/// Nexthop Group
+pub struct NexthopGroup {
+    /// Nexthop id
+    pub id: u32,
+    /// Weight of this nexthop
+    pub weight: u8,
+    /// High order bits of weight
+    pub weight_high: u8,
+    /// Reserved
+    pub resvd2: u16,
+}
+
+impl Emitable for NexthopGroup {
+    fn buffer_len(&self) -> usize {
+        8
+    }
+
+    fn emit(&self, buffer: &mut [u8]) {
+        NativeEndian::write_u32(buffer, self.id);
+        buffer[4] = self.weight;
+        buffer[5] = self.weight_high;
+        NativeEndian::write_u16(&mut buffer[6..8], self.resvd2);
+    }
+}
+
+impl NexthopGroup {
+    pub fn parse(payload: &[u8]) -> Result<Self, DecodeError> {
+        let grp = Self {
+            id: parse_u32(payload)?,
+            weight: payload[4],
+            weight_high: payload[5],
+            resvd2: parse_u16(&payload[6..8])?,
+        };
+        Ok(grp)
+    }
+}