refactor: make internal APIs public for external use

- Change visibility of many internal structs, enums, and methods from
`pub(crate)`to`pub`
- This includes fragmentation components, interface internals, neighbor cache,
socket structures, and wire protocol modules
- Add new public methods to neighbor cache for iteration and inspection
- Update test utilities to be publicly accessible
- No functional changes, only visibility modifications to enable external
library usage

Signed-off-by: longjin <longjin@dragonos.org>

Author: fslongjin

src/iface/fragmentation.rs

@@ -76,15 +76,15 @@ impl<K> PacketAssembler<K> {
         }
     }
 
-    pub(crate) fn reset(&mut self) {
+    pub fn reset(&mut self) {
         self.key = None;
         self.assembler.clear();
         self.total_size = None;
         self.expires_at = Instant::ZERO;
     }
 
     /// Set the total size of the packet assembler.
-    pub(crate) fn set_total_size(&mut self, size: usize) -> Result<(), AssemblerError> {
+    pub fn set_total_size(&mut self, size: usize) -> Result<(), AssemblerError> {
         if let Some(old_size) = self.total_size {
             if old_size != size {
                 return Err(AssemblerError);
@@ -106,11 +106,11 @@ impl<K> PacketAssembler<K> {
     }
 
     /// Return the instant when the assembler expires.
-    pub(crate) fn expires_at(&self) -> Instant {
+    pub fn expires_at(&self) -> Instant {
         self.expires_at
     }
 
-    pub(crate) fn add_with(
+    pub fn add_with(
         &mut self,
         offset: usize,
         f: impl Fn(&mut [u8]) -> Result<usize, AssemblerError>,
@@ -138,7 +138,7 @@ impl<K> PacketAssembler<K> {
     ///
     /// - Returns [`Error::PacketAssemblerBufferTooSmall`] when trying to add data into the buffer at a non-existing
     ///   place.
-    pub(crate) fn add(&mut self, data: &[u8], offset: usize) -> Result<(), AssemblerError> {
+    pub fn add(&mut self, data: &[u8], offset: usize) -> Result<(), AssemblerError> {
         #[cfg(not(feature = "alloc"))]
         if self.buffer.len() < offset + data.len() {
             return Err(AssemblerError);
@@ -164,7 +164,7 @@ impl<K> PacketAssembler<K> {
 
     /// Get an immutable slice of the underlying packet data, if reassembly complete.
     /// This will mark the assembler as empty, so that it can be reused.
-    pub(crate) fn assemble(&mut self) -> Option<&'_ [u8]> {
+    pub fn assemble(&mut self) -> Option<&'_ [u8]> {
         if !self.is_complete() {
             return None;
         }
@@ -176,7 +176,7 @@ impl<K> PacketAssembler<K> {
     }
 
     /// Returns `true` when all fragments have been received, otherwise `false`.
-    pub(crate) fn is_complete(&self) -> bool {
+    pub fn is_complete(&self) -> bool {
         self.total_size == Some(self.assembler.peek_front())
     }
 
@@ -207,7 +207,7 @@ impl<K: Eq + Copy> PacketAssemblerSet<K> {
     /// If it doesn't exist, it is created, with the `expires_at` timestamp.
     ///
     /// If the assembler set is full, in which case an error is returned.
-    pub(crate) fn get(
+    pub fn get(
         &mut self,
         key: &K,
         expires_at: Instant,
@@ -240,19 +240,19 @@ impl<K: Eq + Copy> PacketAssemblerSet<K> {
 
 // Max len of non-fragmented packets after decompression (including ipv6 header and payload)
 // TODO: lower. Should be (6lowpan mtu) - (min 6lowpan header size) + (max ipv6 header size)
-pub(crate) const MAX_DECOMPRESSED_LEN: usize = 1500;
+pub const MAX_DECOMPRESSED_LEN: usize = 1500;
 
 #[cfg(feature = "_proto-fragmentation")]
 #[derive(Debug, Eq, PartialEq, Ord, PartialOrd, Clone, Copy)]
 #[cfg_attr(feature = "defmt", derive(defmt::Format))]
-pub(crate) enum FragKey {
+pub enum FragKey {
     #[cfg(feature = "proto-ipv4-fragmentation")]
     Ipv4(Ipv4FragKey),
     #[cfg(feature = "proto-sixlowpan-fragmentation")]
     Sixlowpan(SixlowpanFragKey),
 }
 
-pub(crate) struct FragmentsBuffer {
+pub struct FragmentsBuffer {
     #[cfg(feature = "proto-sixlowpan")]
     pub decompress_buf: [u8; MAX_DECOMPRESSED_LEN],
 
@@ -264,17 +264,17 @@ pub(crate) struct FragmentsBuffer {
 }
 
 #[cfg(not(feature = "_proto-fragmentation"))]
-pub(crate) struct Fragmenter {}
+pub struct Fragmenter {}
 
 #[cfg(not(feature = "_proto-fragmentation"))]
 impl Fragmenter {
-    pub(crate) fn new() -> Self {
+    pub fn new() -> Self {
         Self {}
     }
 }
 
 #[cfg(feature = "_proto-fragmentation")]
-pub(crate) struct Fragmenter {
+pub struct Fragmenter {
     /// The buffer that holds the unfragmented 6LoWPAN packet.
     pub buffer: [u8; FRAGMENTATION_BUFFER_SIZE],
     /// The size of the packet without the IEEE802.15.4 header and the fragmentation headers.
@@ -289,7 +289,7 @@ pub(crate) struct Fragmenter {
 }
 
 #[cfg(feature = "proto-ipv4-fragmentation")]
-pub(crate) struct Ipv4Fragmenter {
+pub struct Ipv4Fragmenter {
     /// The IPv4 representation.
     pub repr: Ipv4Repr,
     /// The destination hardware address.
@@ -302,7 +302,7 @@ pub(crate) struct Ipv4Fragmenter {
 }
 
 #[cfg(feature = "proto-sixlowpan-fragmentation")]
-pub(crate) struct SixlowpanFragmenter {
+pub struct SixlowpanFragmenter {
     /// The datagram size that is used for the fragmentation headers.
     pub datagram_size: u16,
     /// The datagram tag that is used for the fragmentation headers.
@@ -320,7 +320,7 @@ pub(crate) struct SixlowpanFragmenter {
 
 #[cfg(feature = "_proto-fragmentation")]
 impl Fragmenter {
-    pub(crate) fn new() -> Self {
+    pub fn new() -> Self {
         Self {
             buffer: [0u8; FRAGMENTATION_BUFFER_SIZE],
             packet_len: 0,
@@ -355,18 +355,18 @@ impl Fragmenter {
 
     /// Return `true` when everything is transmitted.
     #[inline]
-    pub(crate) fn finished(&self) -> bool {
+    pub fn finished(&self) -> bool {
         self.packet_len == self.sent_bytes
     }
 
     /// Returns `true` when there is nothing to transmit.
     #[inline]
-    pub(crate) fn is_empty(&self) -> bool {
+    pub fn is_empty(&self) -> bool {
         self.packet_len == 0
     }
 
     // Reset the buffer.
-    pub(crate) fn reset(&mut self) {
+    pub fn reset(&mut self) {
         self.packet_len = 0;
         self.sent_bytes = 0;
 

src/iface/interface/ipv4.rs

@@ -41,7 +41,7 @@ impl InterfaceInner {
     /// **NOTE**: unlike for IPv6, no specific selection algorithm is implemented. The first IPv4
     /// address from the interface is returned.
     #[allow(unused)]
-    pub(crate) fn get_source_address_ipv4(&self, _dst_addr: &Ipv4Address) -> Option<Ipv4Address> {
+    pub fn get_source_address_ipv4(&self, _dst_addr: &Ipv4Address) -> Option<Ipv4Address> {
         for cidr in self.ip_addrs.iter() {
             #[allow(irrefutable_let_patterns)] // if only ipv4 is enabled
             if let IpCidr::Ipv4(cidr) = cidr {
@@ -53,7 +53,7 @@ impl InterfaceInner {
 
     /// Checks if an address is broadcast, taking into account ipv4 subnet-local
     /// broadcast addresses.
-    pub(crate) fn is_broadcast_v4(&self, address: Ipv4Address) -> bool {
+    pub fn is_broadcast_v4(&self, address: Ipv4Address) -> bool {
         if address.is_broadcast() {
             return true;
         }

src/iface/interface/ipv6.rs

@@ -25,7 +25,7 @@ impl InterfaceInner {
     /// # Panics
     /// This function panics if the destination address is unspecified.
     #[allow(unused)]
-    pub(crate) fn get_source_address_ipv6(&self, dst_addr: &Ipv6Address) -> Ipv6Address {
+    pub fn get_source_address_ipv6(&self, dst_addr: &Ipv6Address) -> Ipv6Address {
         assert!(!dst_addr.is_unspecified());
 
         // See RFC 6724 Section 4: Candidate source address

src/iface/interface/mod.rs

@@ -18,7 +18,7 @@ mod ipv6;
 mod sixlowpan;
 
 #[cfg(feature = "multicast")]
-pub(crate) mod multicast;
+pub mod multicast;
 #[cfg(feature = "socket-tcp")]
 mod tcp;
 #[cfg(any(feature = "socket-udp", feature = "socket-dns"))]
@@ -109,7 +109,7 @@ pub enum PollIngressSingleResult {
 /// a dependency on heap allocation, it instead owns a `BorrowMut<[T]>`, which can be
 /// a `&mut [T]`, or `Vec<T>` if a heap is available.
 pub struct Interface {
-    pub(crate) inner: InterfaceInner,
+    pub inner: InterfaceInner,
     fragments: FragmentsBuffer,
     fragmenter: Fragmenter,
 }
@@ -122,8 +122,8 @@ pub struct Interface {
 /// methods on the `Interface` in this time (since its `device` field is borrowed
 /// exclusively). However, it is still possible to call methods on its `inner` field.
 pub struct InterfaceInner {
-    caps: DeviceCapabilities,
-    now: Instant,
+    pub caps: DeviceCapabilities,
+    pub now: Instant,
     rand: Rand,
 
     #[cfg(any(feature = "medium-ethernet", feature = "medium-ieee802154"))]
@@ -762,33 +762,33 @@ impl Interface {
 
 impl InterfaceInner {
     #[allow(unused)] // unused depending on which sockets are enabled
-    pub(crate) fn now(&self) -> Instant {
+    pub fn now(&self) -> Instant {
         self.now
     }
 
     #[cfg(any(feature = "medium-ethernet", feature = "medium-ieee802154"))]
     #[allow(unused)] // unused depending on which sockets are enabled
-    pub(crate) fn hardware_addr(&self) -> HardwareAddress {
+    pub fn hardware_addr(&self) -> HardwareAddress {
         self.hardware_addr
     }
 
     #[allow(unused)] // unused depending on which sockets are enabled
-    pub(crate) fn checksum_caps(&self) -> ChecksumCapabilities {
+    pub fn checksum_caps(&self) -> ChecksumCapabilities {
         self.caps.checksum.clone()
     }
 
     #[allow(unused)] // unused depending on which sockets are enabled
-    pub(crate) fn ip_mtu(&self) -> usize {
+    pub fn ip_mtu(&self) -> usize {
         self.caps.ip_mtu()
     }
 
     #[allow(unused)] // unused depending on which sockets are enabled, and in tests
-    pub(crate) fn rand(&mut self) -> &mut Rand {
+    pub fn rand(&mut self) -> &mut Rand {
         &mut self.rand
     }
 
     #[allow(unused)] // unused depending on which sockets are enabled
-    pub(crate) fn get_source_address(&self, dst_addr: &IpAddress) -> Option<IpAddress> {
+    pub fn get_source_address(&self, dst_addr: &IpAddress) -> Option<IpAddress> {
         match dst_addr {
             #[cfg(feature = "proto-ipv4")]
             IpAddress::Ipv4(addr) => self.get_source_address_ipv4(addr).map(|a| a.into()),
@@ -799,7 +799,7 @@ impl InterfaceInner {
 
     #[cfg(test)]
     #[allow(unused)] // unused depending on which sockets are enabled
-    pub(crate) fn set_now(&mut self, now: Instant) {
+    pub fn set_now(&mut self, now: Instant) {
         self.now = now
     }
 
@@ -895,7 +895,7 @@ impl InterfaceInner {
 
     /// Checks if an address is broadcast, taking into account ipv4 subnet-local
     /// broadcast addresses.
-    pub(crate) fn is_broadcast(&self, address: &IpAddress) -> bool {
+    pub fn is_broadcast(&self, address: &IpAddress) -> bool {
         match address {
             #[cfg(feature = "proto-ipv4")]
             IpAddress::Ipv4(address) => self.is_broadcast_v4(*address),
@@ -938,11 +938,11 @@ impl InterfaceInner {
         }
     }
 
-    fn in_same_network(&self, addr: &IpAddress) -> bool {
+    pub fn in_same_network(&self, addr: &IpAddress) -> bool {
         self.ip_addrs.iter().any(|cidr| cidr.contains_addr(addr))
     }
 
-    fn route(&self, addr: &IpAddress, timestamp: Instant) -> Option<IpAddress> {
+    pub fn route(&self, addr: &IpAddress, timestamp: Instant) -> Option<IpAddress> {
         // Send directly.
         // note: no need to use `self.is_broadcast()` to check for subnet-local broadcast addrs
         //       here because `in_same_network` will already return true.
@@ -1121,6 +1121,12 @@ impl InterfaceInner {
         self.neighbor_cache.flush()
     }
 
+    /// Get the neighbor cache.
+    #[cfg(any(feature = "medium-ethernet", feature = "medium-ieee802154"))]
+    pub fn neighbor_cache(&self) -> &NeighborCache {
+        &self.neighbor_cache
+    }
+
     fn dispatch_ip<Tx: TxToken>(
         &mut self,
         // NOTE(unused_mut): tx_token isn't always mutated, depending on

src/iface/interface/multicast.rs

@@ -19,7 +19,7 @@ pub enum MulticastError {
 }
 
 #[cfg(feature = "proto-ipv4")]
-pub(crate) enum IgmpReportState {
+pub enum IgmpReportState {
     Inactive,
     ToGeneralQuery {
         version: IgmpVersion,
@@ -56,7 +56,7 @@ enum GroupState {
     Leaving,
 }
 
-pub(crate) struct State {
+pub struct State {
     groups: LinearMap<IpAddress, GroupState, IFACE_MAX_MULTICAST_GROUP_COUNT>,
     /// When to report for (all or) the next multicast group membership via IGMP
     #[cfg(feature = "proto-ipv4")]
@@ -66,7 +66,7 @@ pub(crate) struct State {
 }
 
 impl State {
-    pub(crate) fn new() -> Self {
+    pub fn new() -> Self {
         Self {
             groups: LinearMap::new(),
             #[cfg(feature = "proto-ipv4")]
@@ -76,7 +76,7 @@ impl State {
         }
     }
 
-    pub(crate) fn has_multicast_group<T: Into<IpAddress>>(&self, addr: T) -> bool {
+    pub fn has_multicast_group<T: Into<IpAddress>>(&self, addr: T) -> bool {
         // Return false if we don't have the multicast group,
         // or we're leaving it.
         match self.groups.get(&addr.into()) {
@@ -184,7 +184,7 @@ impl Interface {
     /// - Send join/leave packets according to the multicast group state.
     /// - Depending on `igmp_report_state` and the therein contained
     ///   timeouts, send IGMP membership reports.
-    pub(crate) fn multicast_egress(&mut self, device: &mut (impl Device + ?Sized)) {
+    pub fn multicast_egress(&mut self, device: &mut (impl Device + ?Sized)) {
         // Process multicast joins.
         while let Some((&addr, _)) = self
             .inner

src/iface/interface/sixlowpan.rs

@@ -3,7 +3,7 @@ use crate::wire::Result;
 
 // Max len of non-fragmented packets after decompression (including ipv6 header and payload)
 // TODO: lower. Should be (6lowpan mtu) - (min 6lowpan header size) + (max ipv6 header size)
-pub(crate) const MAX_DECOMPRESSED_LEN: usize = 1500;
+pub const MAX_DECOMPRESSED_LEN: usize = 1500;
 
 impl Interface {
     /// Process fragments that still need to be sent for 6LoWPAN packets.

src/iface/interface/tcp.rs

@@ -3,7 +3,7 @@ use super::*;
 use crate::socket::tcp::Socket;
 
 impl InterfaceInner {
-    pub(crate) fn process_tcp<'frame>(
+    pub fn process_tcp<'frame>(
         &mut self,
         sockets: &mut SocketSet,
         ip_repr: IpRepr,

src/iface/mod.rs

@@ -14,7 +14,7 @@ mod rpl;
 mod socket_meta;
 mod socket_set;
 
-mod packet;
+pub mod packet;
 
 #[cfg(feature = "multicast")]
 pub use self::interface::multicast::MulticastError;