From 5ed564d0018a905775cba86a39ccafb1b5fc5c0b Mon Sep 17 00:00:00 2001
From: memN0ps <89628341+memN0ps@users.noreply.github.com>
Date: Fri, 17 May 2024 19:59:42 +1200
Subject: [PATCH] Added HypervisorCommunicator implementation

- Need to handle the requests in the UEFI hypervisor.
- The enhancement issue #20 is half-way complete.
- Testing is required too.
---
 client/src/hypervisor_communicator.rs | 85 +++++++++++++++++++++++++++
 client/src/main.rs                    | 17 +++++-
 2 files changed, 101 insertions(+), 1 deletion(-)
 create mode 100644 client/src/hypervisor_communicator.rs

diff --git a/client/src/hypervisor_communicator.rs b/client/src/hypervisor_communicator.rs
new file mode 100644
index 0000000..6b7db20
--- /dev/null
+++ b/client/src/hypervisor_communicator.rs
@@ -0,0 +1,85 @@
+//! # Hypervisor Communicator
+//!
+//! This library provides functionality to communicate with a UEFI hypervisor
+//! using the CPUID instruction. The communication is password protected to ensure
+//! that only authorized requests are processed by the hypervisor.
+
+use x86::cpuid::cpuid;
+
+/// The password used for authentication with the hypervisor.
+const PASSWORD: u32 = 0xDEADBEEF;
+
+/// Struct to encapsulate the functionality for communicating with the hypervisor.
+pub struct HypervisorCommunicator;
+
+impl HypervisorCommunicator {
+    /// Creates a new instance of `HypervisorCommunicator`.
+    pub fn new() -> Self {
+        Self
+    }
+
+    /// Sends a CPUID command with the specified `eax` and `ecx` values.
+    ///
+    /// # Arguments
+    ///
+    /// * `eax` - The value to be placed in the `eax` register.
+    /// * `ecx` - The value to be placed in the `ecx` register.
+    ///
+    /// # Example
+    ///
+    /// ```
+    /// let communicator = HypervisorCommunicator::new();
+    /// communicator.send_cpuid_command(0x4000_0001, 0x0);
+    /// ```
+    pub fn send_cpuid_command(&self, eax: u32, ecx: u32) {
+        let result = cpuid!(eax, ecx);
+
+        println!(
+            "CPUID with EAX={:#010x}, ECX={:#010x} returned: EAX={:#010x}, EBX={:#010x}, ECX={:#010x}, EDX={:#010x}",
+            eax, ecx, result.eax, result.ebx, result.ecx, result.edx
+        );
+    }
+
+    /// Sends a password-protected CPUID command.
+    ///
+    /// This function includes the password in the CPUID command by setting the `ecx` register to the password value.
+    ///
+    /// # Arguments
+    ///
+    /// * `command` - The value to be placed in the `eax` register.
+    ///
+    /// # Example
+    ///
+    /// ```
+    /// let communicator = HypervisorCommunicator::new();
+    /// communicator.send_protected_cpuid_command(0x4000_0001);
+    /// ```
+    pub fn send_protected_cpuid_command(&self, command: u32) {
+        self.send_cpuid_command(command, PASSWORD);
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    /// Tests the `send_cpuid_command` function.
+    ///
+    /// This test creates a new `HypervisorCommunicator` instance and sends a CPUID command
+    /// with `eax` set to 0x0 and `ecx` set to 0x0. The function is expected to print the CPUID result.
+    #[test]
+    fn test_send_cpuid_command() {
+        let communicator = HypervisorCommunicator::new();
+        communicator.send_cpuid_command(0x0, 0x0);
+    }
+
+    /// Tests the `send_protected_cpuid_command` function.
+    ///
+    /// This test creates a new `HypervisorCommunicator` instance and sends a password-protected CPUID command
+    /// with `eax` set to 0x4000_0001 and `ecx` set to the password value. The function is expected to print the CPUID result.
+    #[test]
+    fn test_send_protected_cpuid_command() {
+        let communicator = HypervisorCommunicator::new();
+        communicator.send_protected_cpuid_command(0x4000_0001);
+    }
+}
diff --git a/client/src/main.rs b/client/src/main.rs
index e7a11a9..72fa84e 100644
--- a/client/src/main.rs
+++ b/client/src/main.rs
@@ -1,3 +1,18 @@
+//! # Hypervisor Communicator
+//!
+//! This demonstrates how to use the `HypervisorCommunicator` library to send
+//! password-protected CPUID commands to a UEFI hypervisor.
+
+use hypervisor_communicator::HypervisorCommunicator;
+
+mod hypervisor_communicator;
+
+/// The main function demonstrating the usage of `HypervisorCommunicator`.
 fn main() {
-    println!("Hello, world!");
+    let communicator = HypervisorCommunicator::new();
+
+    // Example CPUID call
+    let command = 0x36; // Example leaf value, specific to the hypervisor
+
+    communicator.send_protected_cpuid_command(command);
 }