Refactor: Chaning vlek_load api to thake in WrappedVlekHashstick

Since we're updating the major version, I'd prefer having users pass the UAPI structure to the API instead of a slice. By using the UAPI struct, the library can perform the appropriate length and reserved field checks before passing the data to the firmware. This gives us better validation of the data upfront.

This approach is cleaner than passing a raw slice and makes it easier to work with compared to manually managing arrays or buffers.

Signed-off-by: DGonzalezVillal <Diego.GonzalezVillalobos@amd.com>

Author: DGonzalezVillal

src/firmware/host/mod.rs

@@ -289,24 +289,26 @@ impl Firmware {
     ///
     /// let mut firmware: Firmware = Firmware::open().unwrap();
     ///
-    /// // (Optional), Parse the bytes into a `WrappedVlekHashstick` to verify content before passing to the firmware.:
+    /// // Parse the bytes into a `WrappedVlekHashstick` to verify content before passing to the firmware.:
     /// let generation = Generation::identify_host_generation()?;
     /// let hashstick = WrappedVlekHashstick::from_bytes(hashstick_bytes.as_slice(), generation)?;
     ///
-    /// // Parse back into bytes
-    /// let mut buffer: [u8; 432] = [0; 432];
-    /// hashstick.write_bytes(&mut buffer[..], generation)?;
-    ///
     /// // Load the VLEK Hashstick into the AMD Secure Processor.
-    /// firmware.snp_vlek_load(buffer.as_slice()).unwrap();
+    /// firmware.snp_vlek_load(hashstick).unwrap();
     /// ```
-    pub fn snp_vlek_load(&mut self, hashstick_bytes: &[u8]) -> Result<(), UserApiError> {
+    pub fn snp_vlek_load(&mut self, hashstick: WrappedVlekHashstick) -> Result<(), UserApiError> {
         use std::convert::TryFrom;
 
         use types::FFI::types::{SnpVlekLoad, WrappedVlekHashstick as FFIWrappedVlekHashstick};
 
+        let generation = Generation::identify_host_generation()?;
+
+        let mut buffer: [u8; 432] = [0; 432];
+
+        hashstick.write_bytes(&mut buffer[..], generation)?;
+
         let parsed_bytes: FFIWrappedVlekHashstick =
-            FFIWrappedVlekHashstick::try_from(hashstick_bytes)?;
+            FFIWrappedVlekHashstick::try_from(buffer.as_slice())?;
 
         let mut vlek_load: SnpVlekLoad = SnpVlekLoad::new(&parsed_bytes);
         let mut cmd_buf = Command::from_mut(&mut vlek_load);