feat(rust): added the possibility to overwrite http headers in inlets

Author: davide-baldo

Diff for: implementations/rust/ockam/ockam_api/src/http/interceptor.rs

@@ -0,0 +1,309 @@
+use crate::http::state::{ClientRequestWriter, RequestState};
+use crate::nodes::models::services::{DeleteServiceRequest, StartServiceRequest};
+use crate::nodes::registry::HttpHeaderInterceptorInfo;
+use crate::nodes::{NodeManager, NodeManagerWorker};
+use crate::DefaultAddress;
+use httparse::Request;
+use minicbor::{CborLen, Decode, Encode};
+use ockam_abac::{Action, PolicyAccessControl, Resource, ResourceType};
+use ockam_core::api::Response;
+use ockam_core::errcode::{Kind, Origin};
+use ockam_core::{async_trait, Address, AllowAll, IncomingAccessControl, OutgoingAccessControl};
+use ockam_node::Context;
+use ockam_transport_tcp::{
+    read_portal_payload_length, Direction, PortalInletInterceptor, PortalInterceptor,
+    PortalInterceptorFactory,
+};
+use std::io::Write;
+use std::sync::{Arc, Mutex as SyncMutex};
+
+/// An HTTP headers interceptor that rewrites the headers of the HTTP
+/// request with the statically provided headers.
+struct StaticHttpHeadersInterceptor {
+    headers: Arc<Vec<(String, String)>>,
+}
+
+impl StaticHttpHeadersInterceptor {
+    /// Starts a listener that will intercept data in a portal on the inlet side.
+    /// The listener will rewrite the headers of the HTTP request with the provided headers.
+    pub async fn start_listener(
+        context: &Context,
+        listener_address: Address,
+        headers: Vec<(String, String)>,
+        policy_access_control: Option<PolicyAccessControl>,
+    ) -> ockam_core::Result<()> {
+        let flow_control_id = context
+            .flow_controls()
+            .get_flow_control_with_spawner(&Address::from_string(
+                DefaultAddress::SECURE_CHANNEL_LISTENER,
+            ))
+            .ok_or_else(|| {
+                ockam_core::Error::new(
+                    Origin::Channel,
+                    Kind::NotFound,
+                    "Secure channel listener not found",
+                )
+            })?;
+
+        context
+            .flow_controls()
+            .add_consumer(&listener_address, &flow_control_id);
+
+        let incoming_access_control: Arc<dyn IncomingAccessControl>;
+        let outgoing_access_control: Arc<dyn OutgoingAccessControl>;
+        if let Some(policy_access_control) = policy_access_control {
+            incoming_access_control = Arc::new(policy_access_control.create_incoming());
+            outgoing_access_control = Arc::new(policy_access_control.create_outgoing(context)?);
+        } else {
+            incoming_access_control = Arc::new(AllowAll);
+            outgoing_access_control = Arc::new(AllowAll);
+        }
+
+        PortalInletInterceptor::start_listener(
+            context,
+            listener_address,
+            Arc::new(StaticHttpHeadersInterceptor {
+                headers: Arc::new(headers),
+            }),
+            incoming_access_control,
+            outgoing_access_control,
+            read_portal_payload_length(),
+        )
+    }
+}
+
+impl PortalInterceptorFactory for StaticHttpHeadersInterceptor {
+    fn create(&self) -> Arc<dyn PortalInterceptor> {
+        Arc::new(HttpHeadersInterceptor {
+            headers: self.headers.clone(),
+            state: SyncMutex::new(RequestState::ParsingHeader(None)),
+        })
+    }
+}
+
+struct HttpHeadersInterceptor {
+    headers: Arc<Vec<(String, String)>>,
+    state: SyncMutex<RequestState>,
+}
+
+#[async_trait]
+impl PortalInterceptor for HttpHeadersInterceptor {
+    async fn intercept(
+        &self,
+        _context: &mut Context,
+        direction: Direction,
+        buffer: &[u8],
+    ) -> ockam_core::Result<Option<Vec<u8>>> {
+        match direction {
+            Direction::FromOutletToInlet => Ok(Some(buffer.to_vec())),
+            Direction::FromInletToOutlet => {
+                let mut guard = self.state.lock().unwrap();
+                Ok(Some(guard.process_http_buffer(buffer, self)?))
+            }
+        }
+    }
+}
+
+impl ClientRequestWriter for &HttpHeadersInterceptor {
+    fn write_headers(&self, request: &Request, buffer: &mut Vec<u8>) -> ockam_core::Result<()> {
+        write!(
+            buffer,
+            "{} {} HTTP/1.{}\r\n",
+            request.method.unwrap(),
+            request.path.unwrap(),
+            request.version.unwrap()
+        )
+        .unwrap();
+
+        for (name, value) in self.headers.iter() {
+            write!(buffer, "{}: {}\r\n", name, value).unwrap();
+        }
+
+        for h in &*request.headers {
+            if !self
+                .headers
+                .iter()
+                .any(|(name, _)| name.eq_ignore_ascii_case(h.name))
+            {
+                write!(buffer, "{}: ", h.name).unwrap();
+                buffer.extend_from_slice(h.value);
+                buffer.extend_from_slice(b"\r\n");
+            }
+        }
+
+        buffer.extend_from_slice(b"\r\n");
+        Ok(())
+    }
+}
+
+/// Request body to create a new HTTP rewrite headers interceptor
+#[derive(Clone, Debug, Encode, Decode, CborLen)]
+#[rustfmt::skip]
+#[cbor(map)]
+pub struct HttpHeadersInterceptorRequest {
+    #[n(0)] pub headers: Vec<(String, String)>,
+}
+
+impl NodeManagerWorker {
+    pub async fn start_http_header_service(
+        &self,
+        context: &Context,
+        request: StartServiceRequest<HttpHeadersInterceptorRequest>,
+    ) -> ockam_core::Result<Response<()>, Response<ockam_core::api::Error>> {
+        let result = self
+            .node_manager
+            .start_http_header_service(
+                context,
+                Address::from_string(request.address()),
+                request.request().headers.clone(),
+            )
+            .await;
+
+        match result {
+            Ok(_) => Ok(Response::ok().body(())),
+            Err(e) => Err(Response::internal_error_no_request(&e.to_string())),
+        }
+    }
+
+    pub async fn delete_http_overwrite_header_service(
+        &self,
+        context: &Context,
+        request: DeleteServiceRequest,
+    ) -> ockam_core::Result<Response<()>, Response<ockam_core::api::Error>> {
+        let result = self
+            .node_manager
+            .delete_http_overwrite_header_service(context, &Address::from_string(request.address()))
+            .await;
+
+        match result {
+            Ok(_) => Ok(Response::ok().body(())),
+            Err(e) => Err(Response::internal_error_no_request(&e.to_string())),
+        }
+    }
+}
+
+impl NodeManager {
+    pub async fn start_http_header_service(
+        &self,
+        context: &Context,
+        listener_address: Address,
+        headers: Vec<(String, String)>,
+    ) -> ockam_core::Result<()> {
+        let policy_access_control = if let Some(project_authority) = self.project_authority() {
+            Some(
+                self.policy_access_control(
+                    Some(project_authority),
+                    Resource::new(listener_address.to_string(), ResourceType::TcpInlet),
+                    Action::HandleMessage,
+                    None,
+                )
+                .await?,
+            )
+        } else {
+            None
+        };
+
+        StaticHttpHeadersInterceptor::start_listener(
+            context,
+            listener_address.clone(),
+            headers,
+            policy_access_control,
+        )
+        .await?;
+
+        self.registry
+            .http_headers_interceptors
+            .insert(listener_address, HttpHeaderInterceptorInfo {});
+
+        Ok(())
+    }
+
+    pub async fn delete_http_overwrite_header_service(
+        &self,
+        context: &Context,
+        listener_address: &Address,
+    ) -> ockam_core::Result<()> {
+        context.stop_address(listener_address)?;
+
+        self.registry
+            .http_headers_interceptors
+            .remove(listener_address);
+
+        Ok(())
+    }
+}
+
+#[cfg(test)]
+mod test {
+    use super::*;
+    use crate::nodes::service::{NodeManagerCredentialRetrieverOptions, NodeManagerTrustOptions};
+    use crate::test_utils::start_manager_for_tests;
+    use ockam_core::NeutralMessage;
+    use ockam_transport_tcp::PortalMessage;
+
+    #[ockam::test]
+    async fn main(context: &mut Context) -> ockam::Result<()> {
+        let handler = start_manager_for_tests(
+            context,
+            None,
+            Some(NodeManagerTrustOptions::new(
+                NodeManagerCredentialRetrieverOptions::None,
+                NodeManagerCredentialRetrieverOptions::None,
+                None,
+                NodeManagerCredentialRetrieverOptions::None,
+            )),
+        )
+        .await?;
+
+        StaticHttpHeadersInterceptor::start_listener(
+            context,
+            "http_interceptor".into(),
+            vec![("Host".to_string(), "ockam.io".to_string())],
+            None,
+        )
+        .await?;
+
+        let connection = handler
+            .node_manager
+            .make_connection(
+                context,
+                &format!(
+                    "/service/http_interceptor/service/{}",
+                    context.primary_address().address()
+                )
+                .parse()?,
+                handler.node_manager.identifier(),
+                None,
+                None,
+            )
+            .await?;
+
+        let route = connection.route()?;
+
+        context
+            .send(route.clone(), PortalMessage::Ping.to_neutral_message()?)
+            .await?;
+
+        let _ = context.receive::<NeutralMessage>().await?;
+
+        context
+            .send(
+                route.clone(),
+                PortalMessage::Payload(b"GET / HTTP/1.1\r\nHost: localhost\r\n\r\n", None)
+                    .to_neutral_message()?,
+            )
+            .await?;
+
+        let message = context.receive::<NeutralMessage>().await?;
+        let message = PortalMessage::decode(message.payload())?;
+
+        if let PortalMessage::Payload(payload, _) = message {
+            let message = String::from_utf8(payload.to_vec()).unwrap();
+            assert_eq!(message, "GET / HTTP/1.1\r\nHost: ockam.io\r\n\r\n");
+        } else {
+            panic!("Decoded message is not a Payload");
+        }
+
+        Ok(())
+    }
+}

Diff for: implementations/rust/ockam/ockam_api/src/http/mod.rs

@@ -0,0 +1,2 @@
+pub(crate) mod interceptor;
+pub mod state;