Merge branch 'develop' into feature/provider-from-topology

src/utils/mod.rs

@@ -1 +1,4 @@
 pub mod bytes;
+pub mod poisson;
+pub mod sphinx;
+pub mod topology;

src/utils/poisson.rs

@@ -0,0 +1,6 @@
+use rand_distr::{Distribution, Exp};
+
+pub fn sample(average_delay: f64) -> f64 {
+    let exp = Exp::new(1.0 / average_delay).unwrap();
+    exp.sample(&mut rand::thread_rng())
+}

src/utils/sphinx.rs

@@ -0,0 +1,48 @@
+use crate::clients::directory::presence::Topology;
+use crate::utils::{bytes, topology};
+use curve25519_dalek::montgomery::MontgomeryPoint;
+use sphinx::route::{Destination, DestinationAddressBytes, Node, NodeAddressBytes, SURBIdentifier};
+use sphinx::SphinxPacket;
+
+const LOOP_COVER_MESSAGE_PAYLOAD: &[u8] = b"The cake is a lie!";
+
+pub fn loop_cover_message(
+    our_address: DestinationAddressBytes,
+    surb_id: SURBIdentifier,
+    topology: &Topology,
+) -> (NodeAddressBytes, SphinxPacket) {
+    let destination = Destination::new(our_address, surb_id);
+
+    encapsulate_message(destination, LOOP_COVER_MESSAGE_PAYLOAD.to_vec(), topology)
+}
+
+pub fn encapsulate_message(
+    recipient: Destination,
+    message: Vec<u8>,
+    topology: &Topology,
+) -> (NodeAddressBytes, SphinxPacket) {
+    // here we would be getting topology, etc
+
+    let mixes_route = topology::route_from(&topology, 1);
+    let first_provider = topology.mix_provider_nodes.first().unwrap();
+    let decoded_key_bytes =
+        base64::decode_config(&first_provider.pub_key, base64::URL_SAFE).unwrap();
+    let key_bytes = bytes::zero_pad_to_32(decoded_key_bytes);
+    let key = MontgomeryPoint(key_bytes);
+
+    let provider = Node::new(
+        topology::socket_bytes_from_string(first_provider.host.clone()),
+        key,
+    );
+
+    let route = [mixes_route, vec![provider]].concat();
+
+    let delays = sphinx::header::delays::generate(route.len());
+
+    // build the packet
+    let packet = sphinx::SphinxPacket::new(message, &route[..], &recipient, &delays).unwrap();
+
+    let first_node_address = route.first().unwrap().address;
+
+    (first_node_address, packet)
+}

src/utils/topology.rs

@@ -0,0 +1,61 @@
+use crate::clients::directory;
+use crate::clients::directory::presence::Topology;
+use crate::clients::directory::requests::presence_topology_get::PresenceTopologyGetRequester;
+use crate::clients::directory::DirectoryClient;
+use crate::clients::mix::MixClient;
+use crate::clients::provider::ProviderClient;
+use crate::utils::bytes;
+use curve25519_dalek::montgomery::MontgomeryPoint;
+use sphinx::route::Node as SphinxNode;
+use std::net::SocketAddrV4;
+use std::string::ToString;
+
+pub(crate) fn get_topology(is_local: bool) -> Topology {
+    let url = if is_local {
+        "http://localhost:8080".to_string()
+    } else {
+        "https://directory.nymtech.net".to_string()
+    };
+    println!("Using directory server: {:?}", url);
+    let directory_config = directory::Config { base_url: url };
+    let directory = directory::Client::new(directory_config);
+
+    let topology = directory
+        .presence_topology
+        .get()
+        .expect("Failed to retrieve network topology.");
+    topology
+}
+
+pub(crate) fn route_from(topology: &Topology, route_len: usize) -> Vec<SphinxNode> {
+    let mut route = vec![];
+    let nodes = topology.mix_nodes.iter();
+    for mix in nodes.take(route_len) {
+        let address_bytes = socket_bytes_from_string(mix.host.clone());
+        let decoded_key_bytes = base64::decode_config(&mix.pub_key, base64::URL_SAFE).unwrap();
+        let key_bytes = bytes::zero_pad_to_32(decoded_key_bytes);
+        let key = MontgomeryPoint(key_bytes);
+        let sphinx_node = SphinxNode {
+            address: address_bytes,
+            pub_key: key,
+        };
+        route.push(sphinx_node);
+    }
+    route
+}
+
+pub(crate) fn socket_bytes_from_string(address: String) -> [u8; 32] {
+    let socket: SocketAddrV4 = address.parse().unwrap();
+    let host_bytes = socket.ip().octets();
+    let port_bytes = socket.port().to_be_bytes();
+    let mut address_bytes = [0u8; 32];
+
+    address_bytes[0] = host_bytes[0];
+    address_bytes[1] = host_bytes[1];
+    address_bytes[2] = host_bytes[2];
+    address_bytes[3] = host_bytes[3];
+
+    address_bytes[4] = port_bytes[0];
+    address_bytes[5] = port_bytes[1];
+    address_bytes
+}