Use secure DNS for websocket connection establishment (#5386)

implementation of secure dns for websocket connection establishment. depends on #5355

Cargo.lock

@@ -5136,6 +5136,7 @@ dependencies = [
  "nym-explorer-client",
  "nym-gateway-client",
  "nym-gateway-requests",
+ "nym-http-api-client",
  "nym-id",
  "nym-metrics",
  "nym-mixnet-client",
@@ -5747,6 +5748,7 @@ dependencies = [
  "nym-credentials-interface",
  "nym-crypto",
  "nym-gateway-requests",
+ "nym-http-api-client",
  "nym-network-defaults",
  "nym-pemstore",
  "nym-sphinx",

common/client-core/Cargo.toml

@@ -40,6 +40,7 @@ nym-crypto = { path = "../crypto" }
 nym-explorer-client = { path = "../../explorer-api/explorer-client" }
 nym-gateway-client = { path = "../client-libs/gateway-client" }
 nym-gateway-requests = { path = "../gateway-requests" }
+nym-http-api-client = { path = "../http-api-client" }
 nym-metrics = { path = "../nym-metrics" }
 nym-nonexhaustive-delayqueue = { path = "../nonexhaustive-delayqueue" }
 nym-sphinx = { path = "../nymsphinx" }

common/client-core/src/error.rs

@@ -36,6 +36,13 @@ pub enum ClientCoreError {
     #[error("no gateway with id: {0}")]
     NoGatewayWithId(String),
 
+    #[error("Invalid URL: {0}")]
+    InvalidUrl(String),
+
+    #[cfg(not(target_arch = "wasm32"))]
+    #[error("resolution failed: {0}")]
+    ResolutionFailed(#[from] nym_http_api_client::HickoryDnsError),
+
     #[error("no gateways on network")]
     NoGatewaysOnNetwork,
 

common/client-core/src/init/helpers.rs

@@ -15,6 +15,9 @@ use std::{sync::Arc, time::Duration};
 use tungstenite::Message;
 use url::Url;
 
+#[cfg(not(target_arch = "wasm32"))]
+use crate::init::websockets::connect_async;
+
 use nym_topology::NodeId;
 #[cfg(not(target_arch = "wasm32"))]
 use tokio::net::TcpStream;
@@ -23,8 +26,6 @@ use tokio::time::sleep;
 #[cfg(not(target_arch = "wasm32"))]
 use tokio::time::Instant;
 #[cfg(not(target_arch = "wasm32"))]
-use tokio_tungstenite::connect_async;
-#[cfg(not(target_arch = "wasm32"))]
 use tokio_tungstenite::{MaybeTlsStream, WebSocketStream};
 #[cfg(target_arch = "wasm32")]
 use wasm_utils::websocket::JSWebsocket;
@@ -131,7 +132,7 @@ pub async fn gateways_for_init<R: Rng>(
 async fn connect(endpoint: &str) -> Result<WsConn, ClientCoreError> {
     match tokio::time::timeout(CONN_TIMEOUT, connect_async(endpoint)).await {
         Err(_elapsed) => Err(ClientCoreError::GatewayConnectionTimeout),
-        Ok(Err(conn_failure)) => Err(conn_failure.into()),
+        Ok(Err(conn_failure)) => Err(conn_failure),
         Ok(Ok((stream, _))) => Ok(stream),
     }
 }

common/client-core/src/init/mod.rs

@@ -26,6 +26,8 @@ use serde::Serialize;
 
 pub mod helpers;
 pub mod types;
+#[cfg(not(target_arch = "wasm32"))]
+pub(crate) mod websockets;
 
 // helpers for error wrapping
 

common/client-core/src/init/websockets.rs

@@ -0,0 +1,44 @@
+use crate::error::ClientCoreError;
+
+use nym_http_api_client::HickoryDnsResolver;
+use tokio::net::TcpStream;
+use tokio_tungstenite::{MaybeTlsStream, WebSocketStream};
+use tungstenite::handshake::client::Response;
+use url::{Host, Url};
+
+use std::net::SocketAddr;
+
+#[cfg(not(target_arch = "wasm32"))]
+pub(crate) async fn connect_async(
+    endpoint: &str,
+) -> Result<(WebSocketStream<MaybeTlsStream<TcpStream>>, Response), ClientCoreError> {
+    let resolver = HickoryDnsResolver::default();
+    let uri = Url::parse(endpoint).map_err(|_| ClientCoreError::InvalidUrl(endpoint.to_owned()))?;
+    let port: u16 = uri.port_or_known_default().unwrap_or(443);
+
+    let host = uri
+        .host()
+        .ok_or(ClientCoreError::InvalidUrl(endpoint.to_owned()))?;
+
+    // Get address for tcp connection, if a domain is provided use our preferred resolver rather than
+    // the default std resolve
+    let sock_addrs: Vec<SocketAddr> = match host {
+        Host::Ipv4(addr) => vec![SocketAddr::new(addr.into(), port)],
+        Host::Ipv6(addr) => vec![SocketAddr::new(addr.into(), port)],
+        Host::Domain(domain) => {
+            // Do a DNS lookup for the domain using our custom DNS resolver
+            resolver
+                .resolve_str(domain)
+                .await?
+                .into_iter()
+                .map(|a| SocketAddr::new(a, port))
+                .collect()
+        }
+    };
+
+    let stream = TcpStream::connect(&sock_addrs[..]).await?;
+
+    tokio_tungstenite::client_async_tls(endpoint, stream)
+        .await
+        .map_err(Into::into)
+}

common/client-libs/gateway-client/Cargo.toml

@@ -27,6 +27,7 @@ nym-credential-storage = { path = "../../credential-storage" }
 nym-credentials-interface = { path = "../../credentials-interface" }
 nym-crypto = { path = "../../crypto" }
 nym-gateway-requests = { path = "../../gateway-requests" }
+nym-http-api-client = { path = "../../http-api-client" }
 nym-network-defaults = { path = "../../network-defaults" }
 nym-sphinx = { path = "../../nymsphinx" }
 nym-statistics-common = { path = "../../statistics" }

common/client-libs/gateway-client/src/client/mod.rs

@@ -40,8 +40,6 @@ use url::Url;
 use std::os::fd::RawFd;
 #[cfg(not(target_arch = "wasm32"))]
 use tokio::time::sleep;
-#[cfg(not(target_arch = "wasm32"))]
-use tokio_tungstenite::connect_async;
 
 #[cfg(not(unix))]
 use std::os::raw::c_int as RawFd;
@@ -53,6 +51,11 @@ use zeroize::Zeroizing;
 
 pub mod config;
 
+#[cfg(not(target_arch = "wasm32"))]
+pub(crate) mod websockets;
+#[cfg(not(target_arch = "wasm32"))]
+use websockets::connect_async;
+
 pub struct GatewayConfig {
     pub gateway_identity: identity::PublicKey,
 
@@ -201,15 +204,7 @@ impl<C, St> GatewayClient<C, St> {
             "Attemting to establish connection to gateway at: {}",
             self.gateway_address
         );
-        let ws_stream = match connect_async(&self.gateway_address).await {
-            Ok((ws_stream, _)) => ws_stream,
-            Err(error) => {
-                return Err(GatewayClientError::NetworkConnectionFailed {
-                    address: self.gateway_address.clone(),
-                    source: error,
-                })
-            }
-        };
+        let (ws_stream, _) = connect_async(&self.gateway_address).await?;
 
         self.connection = SocketState::Available(Box::new(ws_stream));
 

common/client-libs/gateway-client/src/client/websockets.rs

@@ -0,0 +1,53 @@
+use crate::error::GatewayClientError;
+
+use nym_http_api_client::HickoryDnsResolver;
+use tokio::net::TcpStream;
+use tokio_tungstenite::{MaybeTlsStream, WebSocketStream};
+use tungstenite::handshake::client::Response;
+use url::{Host, Url};
+
+use std::net::SocketAddr;
+
+#[cfg(not(target_arch = "wasm32"))]
+pub(crate) async fn connect_async(
+    endpoint: &str,
+) -> Result<(WebSocketStream<MaybeTlsStream<TcpStream>>, Response), GatewayClientError> {
+    let resolver = HickoryDnsResolver::default();
+    let uri =
+        Url::parse(endpoint).map_err(|_| GatewayClientError::InvalidUrl(endpoint.to_owned()))?;
+    let port: u16 = uri.port_or_known_default().unwrap_or(443);
+
+    let host = uri
+        .host()
+        .ok_or(GatewayClientError::InvalidUrl(endpoint.to_owned()))?;
+
+    // Get address for tcp connection, if a domain is provided use our preferred resolver rather than
+    // the default std resolve
+    let sock_addrs: Vec<SocketAddr> = match host {
+        Host::Ipv4(addr) => vec![SocketAddr::new(addr.into(), port)],
+        Host::Ipv6(addr) => vec![SocketAddr::new(addr.into(), port)],
+        Host::Domain(domain) => {
+            // Do a DNS lookup for the domain using our custom DNS resolver
+            resolver
+                .resolve_str(domain)
+                .await?
+                .into_iter()
+                .map(|a| SocketAddr::new(a, port))
+                .collect()
+        }
+    };
+
+    let stream = TcpStream::connect(&sock_addrs[..]).await.map_err(|error| {
+        GatewayClientError::NetworkConnectionFailed {
+            address: endpoint.to_owned(),
+            source: error.into(),
+        }
+    })?;
+
+    tokio_tungstenite::client_async_tls(endpoint, stream)
+        .await
+        .map_err(|error| GatewayClientError::NetworkConnectionFailed {
+            address: endpoint.to_owned(),
+            source: error,
+        })
+}

common/client-libs/gateway-client/src/error.rs

@@ -44,7 +44,11 @@ pub enum GatewayClientError {
     NetworkConnectionFailed { address: String, source: WsError },
 
     #[error("Invalid URL: {0}")]
-    InvalidURL(String),
+    InvalidUrl(String),
+
+    #[cfg(not(target_arch = "wasm32"))]
+    #[error("resolution failed: {0}")]
+    ResolutionFailed(#[from] nym_http_api_client::HickoryDnsError),
 
     #[error("No shared key was provided or obtained")]
     NoSharedKeyAvailable,

common/http-api-client/src/dns.rs

@@ -40,6 +40,7 @@ struct SocketAddrs {
 
 #[derive(Debug, thiserror::Error)]
 #[error("hickory-dns resolver error: {hickory_error}")]
+/// Error occurring while resolving a hostname into an IP address.
 pub struct HickoryDnsError {
     #[from]
     hickory_error: ResolveError,

common/http-api-client/src/lib.rs

@@ -22,7 +22,7 @@ pub use user_agent::UserAgent;
 #[cfg(not(target_arch = "wasm32"))]
 mod dns;
 #[cfg(not(target_arch = "wasm32"))]
-pub use dns::HickoryDnsResolver;
+pub use dns::{HickoryDnsError, HickoryDnsResolver};
 
 // The timeout is relatively high as we are often making requests over the mixnet, where latency is
 // high and chatty protocols take a while to complete.