Added the basis of communities.

Cargo.toml

@@ -28,6 +28,8 @@ serde = { version = "1.0", features = ["derive"] }
 bincode = "1.1.3"
 rust_sodium = "0.10.2"
 openssl = { version = "0.10", features = ["vendored"] }
+lazy_static = "1.2.0"
+log = "0.4"
 
 [dev-dependencies]
 criterion = "0.2.11"

hooks/pre-commit

@@ -13,17 +13,18 @@ SUCCESS="${GREEN}ok${RC}"
 
 # Check if rustfmt is installed
 printf "${PREFIX} Checking for rustfmt ... "
-command -v cargo fmt &>/dev/null
-if [[ $? == 0 ]]; then
+OUT=$(cargo +stable fmt --version 2>&1 > /dev/null ) # Save the output of the command to OUT for later printing
+if [[ $? -eq 0 ]]; then
     printf "${SUCCESS}\n"
 else
     printf "${FAILURE}\n"
+    printf "${OUT}\n"
     exit 1
 fi
 
 # Check rustfmt against the git tree
 printf "${PREFIX} Checking formatting ... "
-command cargo fmt -- --check > /dev/null
+command cargo +stable fmt -- --check > /dev/null
 if [[ $? == 0 ]]; then
     printf "${SUCCESS}\n"
     exit 0

src/community/mod.rs

@@ -0,0 +1,209 @@
+use crate::serialization::{Packet, PacketDeserializer};
+use crate::serialization::header::Header;
+use std::error::Error;
+use std::collections::HashMap;
+use crate::networking::address::Address;
+use std::fmt;
+
+pub mod peer;
+
+create_error!(
+    HeaderUnwrapError,
+    "The community experienced an error trying to deserialize the header of a packet"
+);
+create_error!(MidError, "Failed to get the mid");
+create_error!(
+    UnknownCommunityError,
+    "No community with matching mid found"
+);
+create_error!(InsertionError, "Error inserting community into hashmap");
+
+/// Example Community
+///
+/// _**Note:** Try to avoid the use of .unwrap() in actual production code, this is just an example_
+/// ```
+/// use ipv8::community::peer::Peer;
+/// use ipv8::community::Community;
+/// use ipv8::serialization::header::Header;
+/// use ipv8::serialization::{PacketDeserializer, Packet};
+/// use std::net::Ipv4Addr;
+/// use ipv8::networking::address::Address;
+/// use std::error::Error;
+/// use ipv8::IPv8;
+/// use ipv8::configuration::Config;
+/// use ipv8::serialization::header::HeaderVersion::PyIPV8Header;
+/// use ipv8::crypto::keytypes::PublicKey;
+///
+/// pub struct TestCommunity{
+///     peer: Peer
+/// }
+///
+/// impl TestCommunity{
+///     fn new() -> Option<Self> {
+///
+///         // Use the highest available key
+///         let pk: PublicKey = PublicKey::from_vec(vec![
+///             48, 129, 167, 48, 16, 6, 7, 42, 134, 72, 206, 61, 2, 1, 6, 5, 43, 129, 4, 0, 39, 3,
+///             129, 146, 0, 4, 2, 86, 251, 75, 206, 159, 133, 120, 63, 176, 235, 178, 14, 8, 197, 59,
+///             107, 51, 179, 139, 3, 155, 20, 194, 112, 113, 15, 40, 67, 115, 37, 223, 152, 7, 102,
+///             154, 214, 90, 110, 180, 226, 5, 190, 99, 163, 54, 116, 173, 121, 40, 80, 129, 142, 82,
+///             118, 154, 96, 127, 164, 248, 217, 91, 13, 80, 91, 94, 210, 16, 110, 108, 41, 57, 4,
+///             243, 49, 52, 194, 254, 130, 98, 229, 50, 84, 21, 206, 134, 223, 157, 189, 133, 50, 210,
+///             181, 93, 229, 32, 179, 228, 179, 132, 143, 147, 96, 207, 68, 48, 184, 160, 47, 227, 70,
+///             147, 23, 159, 213, 105, 134, 60, 211, 226, 8, 235, 186, 20, 241, 85, 170, 4, 3, 40,
+///             183, 98, 103, 80, 164, 128, 87, 205, 101, 67, 254, 83, 142, 133,
+///         ])?;
+///
+///         // Actually create the community
+///         Some(TestCommunity {
+///             peer: Peer::new(
+///                 pk,
+///                 Address{
+///                     address: Ipv4Addr::new(0,0,0,0),
+///                     port: 0
+///                 },
+///                 true,
+///             )
+///         })
+///     }
+/// }
+///
+/// impl Community for TestCommunity{
+///
+///     // Returns the hash of our master peer
+///     fn get_mid(&self) -> Option<Vec<u8>> {
+///         Some(self.peer.get_sha1()?.to_vec())
+///     }
+///
+///     // The function which will be called when the community receives a packet
+///     fn on_receive(&self, header: Header, deserializer: PacketDeserializer, address: Address) -> Result<(),Box<dyn Error>>{
+///         # assert_eq!(header.mid_hash, self.get_mid());
+///         # assert_eq!(header.version, PyIPV8Header);
+///         # assert_eq!(header.message_type, Some(42));
+///         // Do some stuff here like to distribute the message based on it's message_type (in the header)
+///         Ok(())
+///     }
+/// }
+///
+/// let mut config = Config::default();
+/// let community = TestCommunity::new().unwrap();
+/// let mid = community.get_mid();
+/// config.communities.add_community(Box::new(community));
+/// let ipv8 = IPv8::new(config);
+///
+/// // now simulate a packet coming in
+///
+/// // Create a packet to test the community with
+/// let packet = Packet::new(Header{
+///     size: 23,
+///     version: PyIPV8Header,
+///     mid_hash: mid,
+///     message_type: Some(42),
+/// }).unwrap();
+///
+/// // Normally you would want to sign the packet here
+///
+/// // Yeet the packet
+/// ipv8.config.communities.forward_message(packet,Address{
+///     address: Ipv4Addr::new(42,42,42,42),
+///     port: 42,
+/// });
+///
+/// ```
+pub trait Community {
+    //    fn new() -> Option<Self>
+    //    where
+    //        Self: Sized;
+
+    /// Returns the hash of our master peer public key
+    fn get_mid(&self) -> Option<Vec<u8>>;
+
+    /// Gets called whenever a packet is received directed at this community
+    /// DO NOT OVERRIDE
+    fn receive(
+        &self,
+        header: Header,
+        deserializer: PacketDeserializer,
+        address: Address,
+    ) -> Result<(), Box<dyn Error>> {
+        // DO NOT OVERRIDE
+        //! used to pre-decode the header and filter out messages
+
+        fn warn_deprecated(message: &str, address: Address) -> Result<(), Box<dyn Error>> {
+            warn!(
+                "Received deprecated message {} from ({:?})",
+                message, address
+            );
+            Ok(())
+        }
+        match header.message_type.ok_or(HeaderUnwrapError)? {
+            255 => warn_deprecated("reserved-255", address),
+            254 => warn_deprecated("on-missing-sequence", address),
+            253 => warn_deprecated("missing-proof", address),
+            252 => warn_deprecated("signature-request", address),
+            251 => warn_deprecated("signature-response", address),
+            248 => warn_deprecated("on-identity", address),
+            247 => warn_deprecated("on-missing-identity", address),
+            244 => warn_deprecated("destroy-community", address),
+            243 => warn_deprecated("authorize", address),
+            242 => warn_deprecated("revoke", address),
+            241 => warn_deprecated("subjective-set", address),
+            240 => warn_deprecated("missing-subjective-set", address),
+            239 => warn_deprecated("on-missing-message", address),
+            238 => warn_deprecated("undo-own", address),
+            237 => warn_deprecated("undo-other", address),
+            236 => warn_deprecated("dynamic-settings", address),
+            235 => warn_deprecated("missing-last-message", address),
+            _ => self.on_receive(header, deserializer, address),
+        }
+    }
+
+    fn on_receive(
+        &self,
+        header: Header,
+        deserializer: PacketDeserializer,
+        address: Address,
+    ) -> Result<(), Box<dyn Error>>;
+}
+
+pub struct CommunityRegistry {
+    // mid, community
+    communities: HashMap<Vec<u8>, Box<dyn Community>>,
+}
+
+impl CommunityRegistry {
+    pub fn add_community(&mut self, item: Box<dyn Community>) -> Result<(), Box<dyn Error>> {
+        self.communities
+            .insert(item.get_mid().ok_or(MidError)?, item)
+            .ok_or(InsertionError)?;
+        Ok(())
+    }
+
+    /// Forwards the message to the corresponding community
+    pub fn forward_message(&self, packet: Packet, address: Address) -> Result<(), Box<dyn Error>> {
+        // deserialize the header
+        let deserializer = packet.start_deserialize();
+
+        // We use peek here instead of get, even though we give the header along with the receive call
+        // this is because at this point, the header is not verified yet so we still assume the message is valid.
+        // We can't verify the header here yet as not all messages have a signature. Communities will have to decide
+        // on their own if they want to verify the header. We do give it along as only having to deserialize the header once
+        // makes it slightly more efficient.
+        let header = deserializer.peek_header()?;
+
+        // get the mid from the header and use it for a hashtable lookup
+        let mid = header.mid_hash.as_ref().ok_or(MidError)?;
+        let community = self.communities.get(mid).ok_or(UnknownCommunityError)?;
+
+        // Actually forward it
+        community.receive(header, deserializer, address)
+    }
+}
+
+impl Default for CommunityRegistry {
+    fn default() -> Self {
+        Self {
+            communities: HashMap::new(),
+        }
+    }
+}

src/community/peer.rs

@@ -0,0 +1,22 @@
+use crate::crypto::keytypes::PublicKey;
+use crate::networking::address::Address;
+
+pub struct Peer {
+    key: PublicKey,
+    address: Address,
+    intro: bool,
+}
+
+impl Peer {
+    pub fn new(key: PublicKey, address: Address, intro: bool) -> Self {
+        Self {
+            key,
+            address,
+            intro,
+        }
+    }
+
+    pub fn get_sha1(&self) -> Option<[u8; 20]> {
+        self.key.sha1()
+    }
+}

src/configuration.rs

@@ -1,12 +1,16 @@
 use crate::networking::address::Address;
 use std::net::Ipv4Addr;
+use crate::community::CommunityRegistry;
 
 pub struct Config {
     /// Default list of host used for peer discovery
     pub default_hosts: Vec<Address>,
     /// from py-ipv8 configuration. UDP socket address.
     /// There split up in "address" and "port"
     pub socketaddress: Address,
+
+    /// The registry containing all the communities
+    pub communities: CommunityRegistry,
 }
 
 impl Default for Config {
@@ -17,6 +21,8 @@ impl Default for Config {
                 port: 8090,
             },
 
+            communities: CommunityRegistry::default(),
+
             default_hosts: vec![
                 // Dispersy
                 Address {

src/crypto/keytypes.rs

@@ -16,9 +16,11 @@
 //! | HIGH_SIGNATURE_LENGTH            |  144   |   153   |  9   |    144     |
 //! | ED25519_SIGNATURE_LENGTH         |   64   |   64    |  0   |    64      |
 
+use std::fmt;
+
 use openssl;
+use openssl::sha::sha1;
 use rust_sodium::crypto::sign::ed25519;
-use std::fmt;
 
 // TODO: when ed25519 becomes available for rust OpenSSL, rust_sodium will be removed.
 
@@ -129,6 +131,10 @@ impl PublicKey {
             Some(m)
         }
     }
+
+    pub fn sha1(&self) -> Option<[u8; 20]> {
+        Some(sha1(&self.to_vec()?))
+    }
 }
 
 impl PartialEq for PublicKey {
@@ -350,4 +356,25 @@ mod tests {
             keyvec
         );
     }
+
+    #[test]
+    fn test_sha1() {
+        let keyvec = vec![
+            48, 64, 48, 16, 6, 7, 42, 134, 72, 206, 61, 2, 1, 6, 5, 43, 129, 4, 0, 1, 3, 44, 0, 4,
+            0, 80, 239, 172, 104, 165, 76, 172, 6, 229, 136, 156, 105, 23, 249, 46, 30, 148, 87,
+            105, 57, 6, 105, 134, 2, 229, 115, 169, 44, 162, 41, 190, 228, 56, 20, 100, 64, 79,
+            167, 224, 118, 14,
+        ];
+
+        let key = PublicKey::from_vec(keyvec.clone()).unwrap();
+        let sha1sum = key.sha1().unwrap();
+
+        assert_eq!(
+            [
+                254, 127, 138, 49, 67, 126, 206, 58, 169, 85, 132, 14, 211, 247, 13, 170, 244, 166,
+                152, 180,
+            ],
+            sha1sum
+        )
+    }
 }

src/lib.rs

@@ -1,6 +1,10 @@
+#[macro_use]
+extern crate log;
+
 pub mod error;
 pub mod serialization;
 
+pub mod community;
 pub mod configuration;
 pub mod crypto;
 pub mod event;
@@ -17,10 +21,10 @@ use configuration::Config;
 /// use ipv8::IPv8;
 /// use ipv8::configuration::Config;
 ///
-/// let ipv8_instance = IPv8::new(Config::default());
+/// let ipv8 = IPv8::new(Config::default());
 /// ```
 pub struct IPv8 {
-    config: Config,
+    pub config: Config,
 }
 
 impl IPv8 {