I2P Support

Co-authored-by: ps

CHANGELOG.md

@@ -24,6 +24,9 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
   value are asked to keep the substring `/radicle:{YOUR_VERSION}/` which allows
   for better telemetry regarding version distribution on the network.
   To opt-out of sending any meaningful user agent, set `node.userAgent = null`.
+- In addition to connections via SOCKS proxy and Tor for `*.onion` names, now
+  connections via SOCKS proxy and I2P for `*.i2p{,.alt}` names is now supported.
+  To enable making connections via I2P, configure `node.i2p`.
 
 ## 1.8.0
 

crates/radicle-cli/Cargo.toml

@@ -14,7 +14,8 @@ name = "rad"
 path = "src/main.rs"
 
 [features]
-default = ["tor"]
+default = ["i2p", "tor"]
+i2p = ["radicle/i2p"]
 tor = ["radicle/tor"]
 
 [dependencies]

crates/radicle-cli/examples/rad-config.md

@@ -111,12 +111,13 @@ $ rad config schema
       "type": "string"
     },
     "ConnectAddress": {
-      "description": "A node address to connect to. Format: An Ed25519 public key in multibase encoding, followed by the symbol '@', followed by an IP address, or a DNS name, or a Tor onion name, followed by the symbol ':', followed by a TCP port number.",
+      "description": "A node address to connect to. Format: An Ed25519 public key in multibase encoding, followed by the symbol '@', followed by an IP address, or a DNS name, or a Tor onion name, or an I2P address, followed by the symbol ':', followed by a TCP port number.",
       "type": "string",
       "pattern": "^.+@.+:((6553[0-5])|(655[0-2][0-9])|(65[0-4][0-9]{2})|(6[0-4][0-9]{3})|([1-5][0-9]{4})|([0-5]{0,5})|([0-9]{1,4}))$",
       "examples": [
         "z6MkrLMMsiPWUcNPHcRajuMi9mDfYckSoJyPwwnknocNYPm7@rosa.radicle.xyz:8776",
         "z6MkvUJtYD9dHDJfpevWRT98mzDDpdAtmUjwyDSkyqksUr7C@xmrhfasfg5suueegrnc4gsgyi2tyclcy5oz7f5drnrodmdtob6t2ioyd.onion:8776",
+        "z6Mkvky2mnSYCTUMKRdAUoZXBXLLKtnWEkWeYQcGjjnmobAU@f2atcc7udeub5kh4nkljtjwyk7ikjviorufzgwnfwhkphljl3vhq.b32.i2p:8776",
         "z6MknSLrJoTcukLrE435hVNQT4JUhbvWLX4kUzqkEStBU8Vi@seed.example.com:8776",
         "z6MkkfM3tPXNPrPevKr3uSiQtHPuwnNhu2yUVjgd2jXVsVz5@192.0.2.0:31337"
       ]
@@ -260,6 +261,10 @@ $ rad config schema
           "description": "Onion address config.",
           "$ref": "#/$defs/AddressConfig"
         },
+        "i2p": {
+          "description": "I2P address config.",
+          "$ref": "#/$defs/AddressConfig"
+        },
         "network": {
           "description": "Peer-to-peer network.",
           "$ref": "#/$defs/Network",
@@ -383,10 +388,11 @@ $ rad config schema
       ]
     },
     "Address": {
-      "description": "An IP address, or a DNS name, or a Tor onion name, followed by the symbol ':', followed by a TCP port number.",
+      "description": "An IP address, or a DNS name, or a Tor onion name, or an I2P address,followed by the symbol ':', followed by a TCP port number.",
       "type": "string",
       "examples": [
         "xmrhfasfg5suueegrnc4gsgyi2tyclcy5oz7f5drnrodmdtob6t2ioyd.onion:8776",
+        "f2atcc7udeub5kh4nkljtjwyk7ikjviorufzgwnfwhkphljl3vhq.b32.i2p:8776",
         "seed.example.com:8776",
         "192.0.2.0:31337"
       ],

crates/radicle-node/Cargo.toml

@@ -10,7 +10,8 @@ build = "build.rs"
 rust-version.workspace = true
 
 [features]
-default = ["backtrace", "systemd", "structured-logger", "socket2", "tor"]
+default = ["backtrace", "i2p", "systemd", "structured-logger", "socket2", "tor"]
+i2p = ["cyphernet/i2p", "radicle/i2p", "radicle-protocol/i2p"]
 systemd = ["dep:radicle-systemd"]
 test = ["radicle/test", "radicle-crypto/test", "radicle-crypto/cyphernet", "radicle-protocol/test", "qcheck", "snapbox"]
 tor = ["cyphernet/tor", "radicle/tor", "radicle-protocol/tor"]

crates/radicle-node/src/wire.rs

@@ -21,7 +21,7 @@ use radicle::collections::{RandomMap, RandomSet};
 use radicle::crypto;
 use radicle::node::Link;
 use radicle::node::NodeId;
-#[cfg(feature = "tor")]
+#[cfg(any(feature = "i2p", feature = "tor"))]
 use radicle::node::config::AddressConfig;
 use radicle::storage::WriteStorage;
 use radicle_protocol::deserializer::Deserializer;
@@ -1083,6 +1083,30 @@ pub fn dial<G: Ecdh<Pk = NodeId>>(
     signer: G,
     config: &radicle::node::Config,
 ) -> io::Result<WireSession<G>> {
+    #[cfg(any(feature = "i2p", feature = "tor"))]
+    fn proxy_or_forward<H: std::fmt::Display>(
+        config: &AddressConfig,
+        global_proxy: Option<net::SocketAddr>,
+        host: H,
+        port: u16,
+    ) -> io::Result<NetAddr<InetHost>> {
+        match config {
+            // In proxy mode, simply use the configured proxy address.
+            // This takes precedence over any global proxy.
+            AddressConfig::Proxy { address } => Ok((*address).into()),
+            // In "forward" mode, if a global proxy is set, we use that, otherwise
+            // we treat the address as a regular DNS name.
+            AddressConfig::Forward => Ok(global_proxy
+                .map(Into::into)
+                .unwrap_or_else(|| NetAddr::new(InetHost::Dns(host.to_string()), port))),
+            // If address type support isn't configured, refuse to connect.
+            AddressConfig::Drop => Err(io::Error::new(
+                io::ErrorKind::Unsupported,
+                "no configuration found for address type",
+            )),
+        }
+    }
+
     // Determine what address to establish a TCP connection with, given the remote peer
     // address and our node configuration.
     let inet_addr: NetAddr<InetHost> = match (&remote_addr.host, config.proxy) {
@@ -1093,27 +1117,11 @@ pub fn dial<G: Ecdh<Pk = NodeId>>(
         (HostName::Dns(dns), None) => NetAddr::new(InetHost::Dns(dns.clone()), remote_addr.port),
         // For onion addresses, handle with care.
         #[cfg(feature = "tor")]
-        (HostName::Tor(onion), proxy) => match config.onion {
-            // In onion proxy mode, simply use the configured proxy address.
-            // This takes precedence over any global proxy.
-            AddressConfig::Proxy { address } => address.into(),
-            // In "forward" mode, if a global proxy is set, we use that, otherwise
-            // we treat `.onion` addresses as regular DNS names.
-            AddressConfig::Forward => {
-                if let Some(proxy) = proxy {
-                    proxy.into()
-                } else {
-                    NetAddr::new(InetHost::Dns(onion.to_string()), remote_addr.port)
-                }
-            }
-            // If onion address support isn't configured, refuse to connect.
-            AddressConfig::Drop => {
-                return Err(io::Error::new(
-                    io::ErrorKind::Unsupported,
-                    "no configuration found for .onion addresses",
-                ));
-            }
-        },
+        (HostName::Tor(onion), proxy) => {
+            proxy_or_forward(&config.onion, proxy, onion, remote_addr.port)?
+        }
+        #[cfg(feature = "i2p")]
+        (HostName::I2p(i2p), proxy) => proxy_or_forward(&config.i2p, proxy, i2p, remote_addr.port)?,
         _ => {
             return Err(io::Error::new(
                 io::ErrorKind::Unsupported,

crates/radicle-protocol/Cargo.toml

@@ -9,6 +9,7 @@ edition.workspace = true
 rust-version.workspace = true
 
 [features]
+i2p = ["cypheraddr/i2p", "radicle/i2p"]
 test = ["radicle/test", "radicle-crypto/test", "radicle-crypto/cyphernet", "qcheck"]
 tor = ["cypheraddr/tor", "radicle/tor"]
 
@@ -35,4 +36,4 @@ pastey = "0.2"
 qcheck = { workspace = true }
 qcheck-macros = { workspace = true }
 radicle = { workspace = true, features = ["test"] }
-radicle-crypto = { workspace = true, features = ["test", "cyphernet"] }
+radicle-crypto = { workspace = true, features = ["test", "cyphernet"] }

crates/radicle-protocol/src/service.rs

@@ -28,8 +28,6 @@ use radicle::node;
 use radicle::node::address;
 use radicle::node::address::Store as _;
 use radicle::node::address::{AddressBook, AddressType, KnownAddress};
-#[cfg(feature = "tor")]
-use radicle::node::config::AddressConfig;
 use radicle::node::config::{PeerConfig, RateLimit};
 use radicle::node::device::Device;
 use radicle::node::refs::Store as _;
@@ -2652,11 +2650,18 @@ where
     ///
     /// If the [`Address`] is an `.onion` address and the service supports onion
     /// routing then this will return `true`.
+    ///
+    /// # I2P
+    ///
+    /// If the [`Address`] is an I2P address and the service supports I2P
+    /// connections then this will return `true`.
     fn is_supported_address(&self, address: &Address) -> bool {
         match AddressType::from(address) {
             // Only consider onion addresses if configured.
             #[cfg(feature = "tor")]
-            AddressType::Onion => self.config.onion != AddressConfig::Drop,
+            AddressType::Onion => self.config.onion != radicle::node::config::AddressConfig::Drop,
+            #[cfg(feature = "i2p")]
+            AddressType::I2p => self.config.i2p != radicle::node::config::AddressConfig::Drop,
             AddressType::Dns | AddressType::Ipv4 | AddressType::Ipv6 => true,
         }
     }

crates/radicle-protocol/src/wire.rs

@@ -14,6 +14,8 @@ use std::string::FromUtf8Error;
 
 use bytes::{Buf, BufMut};
 
+#[cfg(feature = "i2p")]
+use cypheraddr::i2p;
 #[cfg(feature = "tor")]
 use cypheraddr::tor;
 
@@ -60,6 +62,9 @@ pub enum Invalid {
     #[cfg(feature = "tor")]
     #[error("invalid onion address: {0}")]
     OnionAddr(#[from] tor::OnionAddrDecodeError),
+    #[cfg(feature = "i2p")]
+    #[error("invalid i2p address: {0}")]
+    I2pAddr(#[from] i2p::I2pAddrParseError),
     #[error("invalid timestamp: {actual_millis} millis")]
     Timestamp { actual_millis: u64 },
 
@@ -266,6 +271,13 @@ impl Encode for cypheraddr::tor::OnionAddrV3 {
     }
 }
 
+#[cfg(feature = "i2p")]
+impl Encode for i2p::I2pAddr {
+    fn encode(&self, buf: &mut impl BufMut) {
+        self.to_string().encode(buf)
+    }
+}
+
 impl Encode for UserAgent {
     fn encode(&self, buf: &mut impl BufMut) {
         self.as_ref().encode(buf)
@@ -531,6 +543,16 @@ impl Decode for tor::OnionAddrV3 {
     }
 }
 
+#[cfg(feature = "i2p")]
+impl Decode for i2p::I2pAddr {
+    fn decode(buf: &mut impl Buf) -> Result<Self, Error> {
+        let s = String::decode(buf)?;
+        let addr = i2p::I2pAddr::from_str(&s).map_err(Invalid::from)?;
+
+        Ok(addr)
+    }
+}
+
 impl Encode for Timestamp {
     fn encode(&self, buf: &mut impl BufMut) {
         self.deref().encode(buf)

crates/radicle-protocol/src/wire/message.rs

@@ -2,6 +2,8 @@ use std::{mem, net};
 
 use bytes::Buf;
 use bytes::BufMut;
+#[cfg(feature = "i2p")]
+use cypheraddr::i2p;
 #[cfg(feature = "tor")]
 use cypheraddr::tor;
 use cypheraddr::{HostName, NetAddr};
@@ -83,6 +85,8 @@ pub enum AddressType {
     Dns = 3,
     #[cfg(feature = "tor")]
     Onion = 4,
+    #[cfg(feature = "i2p")]
+    I2p = 5,
 }
 
 impl From<AddressType> for u8 {
@@ -99,6 +103,8 @@ impl From<&Address> for AddressType {
             HostName::Dns(_) => AddressType::Dns,
             #[cfg(feature = "tor")]
             HostName::Tor(_) => AddressType::Onion,
+            #[cfg(feature = "i2p")]
+            HostName::I2p(_) => AddressType::I2p,
             _ => todo!(), // FIXME(cloudhead): Maxim will remove `non-exhaustive`
         }
     }
@@ -114,6 +120,8 @@ impl TryFrom<u8> for AddressType {
             3 => Ok(AddressType::Dns),
             #[cfg(feature = "tor")]
             4 => Ok(AddressType::Onion),
+            #[cfg(feature = "i2p")]
+            5 => Ok(AddressType::I2p),
             _ => Err(other),
         }
     }
@@ -366,6 +374,11 @@ impl wire::Encode for Address {
                 u8::from(AddressType::Onion).encode(buf);
                 addr.encode(buf);
             }
+            #[cfg(feature = "i2p")]
+            HostName::I2p(ref addr) => {
+                u8::from(AddressType::I2p).encode(buf);
+                addr.encode(buf);
+            }
             _ => {
                 unimplemented!(
                     "Encoding not defined for addresses of the same type as the following: {:?}",
@@ -405,6 +418,12 @@ impl wire::Decode for Address {
 
                 HostName::Tor(onion)
             }
+            #[cfg(feature = "i2p")]
+            Ok(AddressType::I2p) => {
+                let i2p: i2p::I2pAddr = wire::Decode::decode(buf)?;
+
+                HostName::I2p(i2p)
+            }
             Err(other) => return Err(wire::Invalid::AddressType { actual: other }.into()),
         };
         let port = u16::decode(buf)?;

crates/radicle/Cargo.toml

@@ -13,6 +13,7 @@ rust-version.workspace = true
 bstr = ["radicle-git-ref-format/bstr"]
 default = []
 gix = ["radicle-oid/gix"]
+i2p = ["cyphernet/i2p"]
 test = ["tempfile", "qcheck", "radicle-crypto/test", "radicle-cob/test"]
 logger = ["colored", "chrono"]
 qcheck = [

crates/radicle/src/node.rs

@@ -468,11 +468,11 @@ impl TryFrom<&sqlite::Value> for Alias {
     feature = "schemars",
     derive(schemars::JsonSchema),
     schemars(description = "\
-    An IP address, or a DNS name, or a Tor onion name, followed by the symbol ':', \
-    followed by a TCP port number.",
-    extend(
-        "examples" = [
+    An IP address, or a DNS name, or a Tor onion name, or an I2P address,\
+    followed by the symbol ':', followed by a TCP port number.",
+    extend("examples" = [
             "xmrhfasfg5suueegrnc4gsgyi2tyclcy5oz7f5drnrodmdtob6t2ioyd.onion:8776",
+            "f2atcc7udeub5kh4nkljtjwyk7ikjviorufzgwnfwhkphljl3vhq.b32.i2p:8776",
             "seed.example.com:8776",
             "192.0.2.0:31337",
         ],
@@ -517,6 +517,12 @@ impl Address {
         matches!(self.0.host, HostName::Tor(_))
     }
 
+    /// Returns `true` if the [`HostName`] is an I2P address.
+    #[cfg(feature = "i2p")]
+    pub fn is_i2p(&self) -> bool {
+        matches!(self.0.host, HostName::I2p(_))
+    }
+
     /// Return the port number of the [`Address`].
     pub fn port(&self) -> u16 {
         self.0.port
@@ -537,6 +543,8 @@ impl Address {
                     .collect::<String>();
                 format!("{start}…{end}")
             }
+            #[cfg(feature = "i2p")]
+            HostName::I2p(i2p) => i2p.to_string(),
             _ => unreachable!(),
         };
 

crates/radicle/src/node/address.rs

@@ -203,6 +203,8 @@ pub enum AddressType {
     Dns = 3,
     #[cfg(feature = "tor")]
     Onion = 4,
+    #[cfg(feature = "i2p")]
+    I2p = 5,
 }
 
 impl From<AddressType> for u8 {
@@ -219,6 +221,8 @@ impl From<&Address> for AddressType {
             HostName::Dns(_) => AddressType::Dns,
             #[cfg(feature = "tor")]
             HostName::Tor(_) => AddressType::Onion,
+            #[cfg(feature = "i2p")]
+            HostName::I2p(_) => AddressType::I2p,
             _ => todo!(), // FIXME(cloudhead): Maxim will remove `non-exhaustive`
         }
     }
@@ -234,6 +238,8 @@ impl TryFrom<u8> for AddressType {
             3 => Ok(AddressType::Dns),
             #[cfg(feature = "tor")]
             4 => Ok(AddressType::Onion),
+            #[cfg(feature = "i2p")]
+            5 => Ok(AddressType::I2p),
             _ => Err(other),
         }
     }

crates/radicle/src/node/address/store.rs

@@ -537,6 +537,8 @@ impl TryFrom<&sql::Value> for AddressType {
                 "dns" => Ok(AddressType::Dns),
                 #[cfg(feature = "tor")]
                 "onion" => Ok(AddressType::Onion),
+                #[cfg(feature = "i2p")]
+                "i2p" => Ok(AddressType::I2p),
                 _ => Err(err),
             },
             _ => Err(err),
@@ -552,6 +554,8 @@ impl sql::BindableWithIndex for AddressType {
             Self::Dns => "dns".bind(stmt, i),
             #[cfg(feature = "tor")]
             Self::Onion => "onion".bind(stmt, i),
+            #[cfg(feature = "i2p")]
+            Self::I2p => "i2p".bind(stmt, i),
         }
     }
 }

crates/radicle/src/node/config.rs

@@ -278,7 +278,7 @@ pub struct RateLimits {
     schemars(description = "\
     A node address to connect to. Format: An Ed25519 public key in multibase encoding, \
     followed by the symbol '@', followed by an IP address, or a DNS name, or a Tor onion \
-    name, followed by the symbol ':', followed by a TCP port number.\
+    name, or an I2P address, followed by the symbol ':', followed by a TCP port number.\
 ")
 )]
 pub struct ConnectAddress(
@@ -289,6 +289,7 @@ pub struct ConnectAddress(
         extend("examples" = [
             "z6MkrLMMsiPWUcNPHcRajuMi9mDfYckSoJyPwwnknocNYPm7@rosa.radicle.xyz:8776",
             "z6MkvUJtYD9dHDJfpevWRT98mzDDpdAtmUjwyDSkyqksUr7C@xmrhfasfg5suueegrnc4gsgyi2tyclcy5oz7f5drnrodmdtob6t2ioyd.onion:8776",
+            "z6Mkvky2mnSYCTUMKRdAUoZXBXLLKtnWEkWeYQcGjjnmobAU@f2atcc7udeub5kh4nkljtjwyk7ikjviorufzgwnfwhkphljl3vhq.b32.i2p:8776",
             "z6MknSLrJoTcukLrE435hVNQT4JUhbvWLX4kUzqkEStBU8Vi@seed.example.com:8776",
             "z6MkkfM3tPXNPrPevKr3uSiQtHPuwnNhu2yUVjgd2jXVsVz5@192.0.2.0:31337",
         ]),
@@ -358,7 +359,7 @@ pub enum Relay {
 #[derive(Debug, Copy, Clone, Default, PartialEq, Serialize, Deserialize)]
 #[serde(rename_all = "camelCase", tag = "mode")]
 #[cfg_attr(feature = "schemars", derive(schemars::JsonSchema))]
-#[cfg(feature = "tor")]
+#[cfg(any(feature = "i2p", feature = "tor"))]
 pub enum AddressConfig {
     /// Proxy connections to this address type.
     Proxy {
@@ -561,6 +562,10 @@ pub struct Config {
         deserialize_with = "crate::serde_ext::null_to_default"
     )]
     pub onion: AddressConfig,
+    /// I2P address config.
+    #[cfg(feature = "i2p")]
+    #[serde(default, skip_serializing_if = "crate::serde_ext::is_default")]
+    pub i2p: AddressConfig,
     /// Peer-to-peer network.
     #[serde(default)]
     pub network: Network,
@@ -618,6 +623,8 @@ impl Config {
             proxy: None,
             #[cfg(feature = "tor")]
             onion: AddressConfig::Drop,
+            #[cfg(feature = "i2p")]
+            i2p: AddressConfig::Drop,
             relay: Relay::default(),
             limits: Limits::default(),
             workers: Workers::default(),

crates/radicle/src/test/arbitrary.rs

@@ -5,6 +5,8 @@ use std::str::FromStr;
 use std::{iter, net};
 
 use crypto::PublicKey;
+#[cfg(feature = "i2p")]
+use cyphernet::addr::i2p::I2pAddr;
 #[cfg(feature = "tor")]
 use cyphernet::{EcPk, addr::tor::OnionAddrV3};
 use qcheck::Arbitrary;
@@ -208,10 +210,14 @@ impl Arbitrary for MockRepository {
 
 impl Arbitrary for AddressType {
     fn arbitrary(g: &mut qcheck::Gen) -> Self {
-        #[cfg(not(feature = "tor"))]
-        let types = [1, 2, 3];
+        #[allow(unused_mut)]
+        let mut types = vec![1, 2, 3];
+
         #[cfg(feature = "tor")]
-        let types = [1, 2, 3, 4];
+        types.push(4);
+
+        #[cfg(feature = "i2p")]
+        types.push(5);
 
         let t = *g.choose(&types).unwrap() as u8;
 
@@ -238,11 +244,40 @@ impl Arbitrary for Address {
             AddressType::Onion => {
                 let pk = PublicKey::arbitrary(g);
                 let addr = OnionAddrV3::from(
-                    cyphernet::ed25519::PublicKey::from_pk_compressed(pk.to_byte_array())
-                        .unwrap(),
+                    cyphernet::ed25519::PublicKey::from_pk_compressed(pk.to_byte_array()).unwrap(),
                 );
                 cyphernet::addr::HostName::Tor(addr)
             }
+            #[cfg(feature = "i2p")]
+            AddressType::I2p => {
+                let address = if bool::arbitrary(g) {
+                    let name: String = iter::repeat_with(|| {
+                        char::from(
+                            // Base32 alphabet from RFC 4648.
+                            *g.choose(b"ABCDEFGHIJKLMNOPQRSTUVWXYZ234567")
+                                .expect("alphabet is non-empty"),
+                        )
+                    })
+                    .take(56)
+                    .collect();
+
+                    name + ".b32"
+                } else {
+                    g.choose(&["iris.radicle.example", "rosa.radicle.example"])
+                        .unwrap()
+                        .to_string()
+                };
+
+                let suffix = if bool::arbitrary(g) {
+                    ".i2p"
+                } else {
+                    ".i2p.alt"
+                };
+
+                let address = address + suffix;
+
+                cyphernet::addr::HostName::I2p(I2pAddr::from_str(&address).unwrap())
+            }
         };
 
         Address::from(cyphernet::addr::NetAddr {