kernel/vsock: add in-svsm tests for VsockStream

Add a test that performs some basic checks on vsock functionalities:

- double connection
- recv a buffer from the host
- send a buffer to the host
- recv a buffer after local shutdown
- send a buffer after local shutdown

The vsock server is created on the host using ncat.

Signed-off-by: Luigi Leonardi <leonardi@redhat.com>

Author: luigix25

Makefile

@@ -4,7 +4,7 @@ SVSM_ARGS += --features ${FEATURES}
 XBUILD_ARGS += -f ${FEATURES}
 endif
 
-FEATURES_TEST ?= vtpm,virtio-drivers,block
+FEATURES_TEST ?= vtpm,virtio-drivers,block,vsock
 SVSM_ARGS_TEST += --no-default-features
 ifneq ($(FEATURES_TEST),)
 SVSM_ARGS_TEST += --features ${FEATURES_TEST}

kernel/src/testing.rs

@@ -39,6 +39,8 @@ pub enum IORequest {
     GetLaunchMeasurement = 0x01,
     /// Virtio-blk tests: Get Sha256 hash of the svsm state disk image
     GetStateImageSha256 = 0x02,
+    /// Virtio-vsock tests: Ask host to start a vsock server
+    StartVsockServer = 0x03,
 }
 
 /// Return the serial port to communicate with the host for a given request

kernel/src/vsock/stream.rs

@@ -184,3 +184,133 @@ impl Drop for VsockStream {
         let _ = VSOCK_DEVICE.force_shutdown(self.remote_cid, self.local_port, self.remote_port);
     }
 }
+
+#[cfg(all(test, test_in_svsm))]
+mod tests {
+    use crate::{testutils::has_test_iorequests, vsock::VMADDR_CID_HOST};
+
+    use super::*;
+
+    fn start_vsock_server_host() {
+        use crate::serial::Terminal;
+        use crate::testing::{IORequest, svsm_test_io};
+
+        let sp = svsm_test_io().unwrap();
+
+        sp.put_byte(IORequest::StartVsockServer as u8);
+
+        let _ = sp.get_byte();
+    }
+
+    #[test]
+    #[cfg_attr(not(test_in_svsm), ignore = "Can only be run inside guest")]
+    fn test_virtio_vsock_double_connect() {
+        if !has_test_iorequests() {
+            return;
+        }
+
+        start_vsock_server_host();
+
+        let remote_port: u32 = 12345;
+
+        let mut stream =
+            VsockStream::connect(remote_port, VMADDR_CID_HOST).expect("connection failed");
+
+        VsockStream::connect(remote_port, VMADDR_CID_HOST)
+            .expect_err("The second connection operation was expected to fail, but it succeeded.");
+
+        stream.shutdown().expect("shutdown failed");
+    }
+
+    #[test]
+    #[cfg_attr(not(test_in_svsm), ignore = "Can only be run inside guest")]
+    fn test_virtio_vsock_write() {
+        if !has_test_iorequests() {
+            return;
+        }
+
+        start_vsock_server_host();
+
+        let remote_port: u32 = 12345;
+
+        let mut stream =
+            VsockStream::connect(remote_port, VMADDR_CID_HOST).expect("connection failed");
+
+        let buffer: &[u8] = b"Hello world!";
+
+        let n_bytes = stream.write(buffer).expect("write failed");
+        assert!(n_bytes == buffer.len(), "Sent less bytes than requested");
+
+        stream.shutdown().expect("shutdown failed");
+    }
+
+    #[test]
+    #[cfg_attr(not(test_in_svsm), ignore = "Can only be run inside guest")]
+    fn test_virtio_vsock_read() {
+        if !has_test_iorequests() {
+            return;
+        }
+
+        start_vsock_server_host();
+
+        let remote_port: u32 = 12345;
+
+        let mut stream =
+            VsockStream::connect(remote_port, VMADDR_CID_HOST).expect("connection failed");
+
+        let mut buffer: [u8; 11] = [0; 11];
+        let n_bytes = stream.read(&mut buffer).expect("read failed");
+        assert!(
+            n_bytes == buffer.len(),
+            "Received less bytes than requested"
+        );
+
+        let string = core::str::from_utf8(&buffer).unwrap();
+        log::info!("received: {string:?}");
+
+        stream.shutdown().expect("shutdown failed");
+    }
+
+    #[test]
+    #[cfg_attr(not(test_in_svsm), ignore = "Can only be run inside guest")]
+    fn test_virtio_vsock_read_shutdown() {
+        if !has_test_iorequests() {
+            return;
+        }
+
+        start_vsock_server_host();
+
+        let remote_port: u32 = 12345;
+
+        let mut stream =
+            VsockStream::connect(remote_port, VMADDR_CID_HOST).expect("connection failed");
+
+        stream.shutdown().expect("shutdown failed");
+
+        let mut buffer: [u8; 11] = [0; 11];
+        stream
+            .read(&mut buffer)
+            .expect_err("The read operation was expected to fail, but it succeeded");
+    }
+
+    #[test]
+    #[cfg_attr(not(test_in_svsm), ignore = "Can only be run inside guest")]
+    fn test_virtio_vsock_write_shutdown() {
+        if !has_test_iorequests() {
+            return;
+        }
+
+        start_vsock_server_host();
+
+        let remote_port: u32 = 12345;
+
+        let mut stream =
+            VsockStream::connect(remote_port, VMADDR_CID_HOST).expect("connection failed");
+
+        stream.shutdown().expect("shutdown failed");
+
+        stream
+            .write(b"hello world")
+            .expect_err("The write operation was expected to fail, but it succeeded");
+    }
+}

scripts/test-in-svsm.sh

@@ -28,6 +28,12 @@ test_io(){
             "02")
               sha256sum "$TEST_DIR/svsm_state.raw" | cut -f 1 -d ' ' | xxd -p -r > "$PIPE_IN"
               ;;
+            "03")
+              # virtio-vsock in svsm does not handle half duplex connections.
+              echo -n "hello_world" | ncat --no-shutdown -l --vsock -p 12345 &
+              sleep 1
+              echo -n "0" > $PIPE_IN
+              ;;
             "")
                 # skip EOF
                 ;;
@@ -69,6 +75,7 @@ done
 
 $SCRIPT_DIR/launch_guest.sh --igvm $SCRIPT_DIR/../bin/coconut-test-qemu.igvm \
     --state "$TEST_DIR/svsm_state.raw" \
+    --vsock 3 \
     --unit-tests $TEST_DIR/pipe \
     $LAUNCH_GUEST_ARGS "$@" || svsm_exit_code=$?