add get_rng wrapper

Author: gelven4sec

src/proto/rng.rs

@@ -1,14 +1,17 @@
 //! `Rng` protocol.
 
 use crate::{data_types::Guid, proto::Protocol, unsafe_guid, Result, Status};
-use core::slice::SliceIndex;
+use core::ptr;
 
 /// Contain a Rng algorithm Guid
 #[repr(C)]
 #[derive(Clone, Copy, Debug)]
 pub struct RngAlgorithm(pub Guid);
 
 impl RngAlgorithm {
+ /// Get an empty `RngAlgorithm`
+ ///
+ /// Used provide a buffer to `Rng.get_info`
  pub fn default() -> Self {
  Self(Guid::default())
  }
@@ -26,19 +29,40 @@ pub struct Rng {
  ) -> Status,
  get_rng: extern "efiapi" fn(
  this: &Rng,
- algorithm: Option<RngAlgorithm>,
+ algorithm: *const RngAlgorithm,
  value_length: usize,
  value: *mut u8,
  ) -> Status,
 }
 
 impl Rng {
+ /// Returns information about the random number generation implementation.
+ ///
+ /// Exemple :
+ /// ```
+ /// use uefi::proto::rng::RngAlgorithm;
+ ///
+ /// let mut buffer = [RngAlgorithm::default(); 4];
+ /// rng.get_info().unwrap_success();
+ /// ```
  pub fn get_info(&mut self, algorithm_list: &mut [RngAlgorithm]) -> Result<usize> {
- let mut algorithm_list_size = (algorithm_list.len() * 16) as *mut usize;
+ let algorithm_list_size = (algorithm_list.len() * 16) as *mut usize;
 
  (self.get_info)(self, algorithm_list_size, algorithm_list.as_mut_ptr())
  .into_with_val(|| algorithm_list_size as usize / 16)
 
  // TODO: Add AlgorithmType Enum for better visibility on algorithms
  }
+
+ /// Returns the next set of random numbers
+ pub fn get_rng(&mut self, algorithm: Option<RngAlgorithm>, buffer: &mut [u8]) -> Result {
+ let buffer_length = buffer.len();
+
+ let algo = match algorithm {
+ None => ptr::null(),
+ Some(algo) => &algo as *const RngAlgorithm,
+ };
+
+ (self.get_rng)(self, algo, buffer_length, buffer.as_mut_ptr()).into()
+ }
 }

uefi-test-runner/src/proto/rng.rs

@@ -1,9 +1,6 @@
-use core::mem;
-use core::mem::size_of_val;
 use uefi::prelude::*;
 use uefi::proto::rng::{Rng, RngAlgorithm};
 use uefi::table::boot::{BootServices, OpenProtocolAttributes, OpenProtocolParams};
-use uefi::Guid;
 
 pub fn test(image: Handle, bt: &BootServices) {
  info!("Running rng protocol test");
@@ -28,14 +25,11 @@ pub fn test(image: Handle, bt: &BootServices) {
 
  let mut list = [RngAlgorithm::default(); 4];
 
- match rng.get_info(&mut list) {
- Ok(nb) => {
- for i in 0..nb.unwrap() {
- info!("OK {} : {}", nb.unwrap(), list[i].0)
- }
- }
- Err(e) => {
- error!("ERROR : {:#?}", e.status())
- }
- }
+ rng.get_info(&mut list).unwrap_success();
+
+ let mut buf = [0u8; 4];
+
+ rng.get_rng(Some(list[0]), &mut buf).unwrap_success();
+
+ assert_ne!([0u8; 4], buf);
 }