client: enable IPv6 NAT candidate reporting (#192)

client/src/main.rs

@@ -602,10 +602,13 @@ fn fetch(
         .map(|addr| SocketAddr::from((addr, device.listen_port.unwrap_or(51820))).into())
         .collect::<Vec<Endpoint>>();
     log::info!(
-        "reporting {} interface address{} as NAT traversal candidates...",
+        "reporting {} interface address{} as NAT traversal candidates",
         candidates.len(),
-        if candidates.len() == 1 { "" } else { "es" }
+        if candidates.len() == 1 { "" } else { "es" },
     );
+    for candidate in &candidates {
+        log::debug!("  candidate: {}", candidate);
+    }
     match api.http_form::<_, ()>("PUT", "/user/candidates", &candidates) {
         Err(ureq::Error::Status(404, _)) => {
             log::warn!("your network is using an old version of innernet-server that doesn't support NAT traversal candidate reporting.")

shared/src/lib.rs

@@ -2,6 +2,7 @@ pub use anyhow::Error;
 use std::{
     fs::{self, File, Permissions},
     io,
+    net::{IpAddr, Ipv6Addr},
     os::unix::fs::PermissionsExt,
     path::Path,
     time::Duration,
@@ -86,7 +87,7 @@ pub fn _get_local_addrs() -> Result<impl Iterator<Item = std::net::IpAddr>, io::
                 )
         })
         .filter_map(|addr| match addr.address {
-            Some(SockAddr::Inet(addr)) if addr.to_std().is_ipv4() => Some(addr.to_std().ip()),
+            Some(SockAddr::Inet(addr)) => Some(addr.to_std().ip()),
             _ => None,
         });
 
@@ -97,5 +98,21 @@ pub fn _get_local_addrs() -> Result<impl Iterator<Item = std::net::IpAddr>, io::
 pub use netlink::get_local_addrs as _get_local_addrs;
 
 pub fn get_local_addrs() -> Result<impl Iterator<Item = std::net::IpAddr>, io::Error> {
-    Ok(_get_local_addrs()?.take(10))
+    // TODO(jake): this is temporary pending the stabilization of rust-lang/rust#27709
+    fn is_unicast_global(ip: &Ipv6Addr) -> bool {
+        !((ip.segments()[0] & 0xff00) == 0xff00 // multicast
+            || ip.is_loopback()
+            || ip.is_unspecified()
+            || ((ip.segments()[0] == 0x2001) && (ip.segments()[1] == 0xdb8)) // documentation
+            || (ip.segments()[0] & 0xffc0) == 0xfe80 // unicast link local
+            || (ip.segments()[0] & 0xfe00) == 0xfc00) // unicast local
+    }
+
+    Ok(_get_local_addrs()?
+        .filter(|ip| {
+            ip.is_ipv4()
+                || matches!(ip,
+            IpAddr::V6(v6) if is_unicast_global(v6))
+        })
+        .take(10))
 }

shared/src/netlink.rs

@@ -159,7 +159,10 @@ pub fn get_local_addrs() -> Result<impl Iterator<Item = IpAddr>, io::Error> {
                 None
             })
         // Only select addresses for helpful links
-        .filter(move |nlas| nlas.iter().any(|nla| matches!(nla, address::nlas::Nla::Label(label) if links.contains(label))))
+        .filter(move |nlas| nlas.iter().any(|nla| {
+            matches!(nla, address::nlas::Nla::Label(label) if links.contains(label))
+            || matches!(nla, address::nlas::Nla::Address(name) if name.len() == 16)
+        }))
         .filter_map(|nlas| nlas.iter().find_map(|nla| match nla {
             address::nlas::Nla::Address(name) if name.len() == 4 => {
                 let mut addr = [0u8; 4];