uefi: Use uefi_raw for the TCG v1 protocol

Author: nicholasbishop

uefi/src/proto/tcg/v1.rs

@@ -17,89 +17,60 @@ use core::fmt::{self, Debug, Formatter};
 use core::marker::PhantomData;
 use core::{mem, ptr};
 use ptr_meta::Pointee;
+use uefi_raw::protocol::tcg::v1::{TcgBootServiceCapability, TcgProtocol};
 
 #[cfg(feature = "alloc")]
 use {crate::mem::make_boxed, alloc::boxed::Box};
 
 #[cfg(all(feature = "unstable", feature = "alloc"))]
 use alloc::alloc::Global;
 
+pub use uefi_raw::protocol::tcg::v1::TcgVersion as Version;
+
 /// 20-byte SHA-1 digest.
 pub type Sha1Digest = [u8; 20];
 
-/// This corresponds to the `AlgorithmId` enum, but in the v1 spec it's `u32`
-/// instead of `u16`.
-#[allow(non_camel_case_types)]
-type TCG_ALGORITHM_ID = u32;
-
 /// Information about the protocol and the TPM device.
 ///
 /// Layout compatible with the C type `TCG_EFI_BOOT_SERVICE_CAPABILITY`.
 #[repr(C)]
 #[derive(Clone, Copy, Debug, Default, Eq, PartialEq, Ord, PartialOrd)]
-pub struct BootServiceCapability {
-    size: u8,
-    structure_version: Version,
-    protocol_spec_version: Version,
-    hash_algorithm_bitmap: u8,
-    tpm_present_flag: u8,
-    tpm_deactivated_flag: u8,
-}
+pub struct BootServiceCapability(TcgBootServiceCapability);
 
 impl BootServiceCapability {
     /// Version of the `BootServiceCapability` structure.
     #[must_use]
     pub const fn structure_version(&self) -> Version {
-        self.structure_version
+        self.0.structure_version
     }
 
     /// Version of the `Tcg` protocol.
     #[must_use]
     pub const fn protocol_spec_version(&self) -> Version {
-        self.protocol_spec_version
+        self.0.protocol_spec_version
     }
 
     /// Supported hash algorithms.
     #[must_use]
     pub fn hash_algorithm(&self) -> HashAlgorithm {
         // Safety: the value should always be 0x1 (indicating SHA-1), but
         // we don't care if it's some unexpected value.
-        HashAlgorithm::from_bits_retain(u32::from(self.hash_algorithm_bitmap))
+        HashAlgorithm::from_bits_retain(u32::from(self.0.hash_algorithm_bitmap))
     }
 
     /// Whether the TPM device is present.
     #[must_use]
     pub const fn tpm_present(&self) -> bool {
-        self.tpm_present_flag != 0
+        self.0.tpm_present_flag != 0
     }
 
     /// Whether the TPM device is deactivated.
     #[must_use]
     pub const fn tpm_deactivated(&self) -> bool {
-        self.tpm_deactivated_flag != 0
+        self.0.tpm_deactivated_flag != 0
     }
 }
 
-/// Version information.
-///
-/// Layout compatible with the C type `TCG_VERSION`.
-#[repr(C)]
-#[derive(Clone, Copy, Debug, Default, Eq, PartialEq, Ord, PartialOrd)]
-pub struct Version {
-    /// Major version.
-    pub major: u8,
-    /// Minor version.
-    pub minor: u8,
-
-    // Leave these two fields undocumented since it's not clear what
-    // they are for. The spec doesn't say, and they were removed in the
-    // v2 spec.
-    #[allow(missing_docs)]
-    pub rev_major: u8,
-    #[allow(missing_docs)]
-    pub rev_minor: u8,
-}
-
 /// Entry in the [`EventLog`].
 ///
 /// Layout compatible with the C type `TCG_PCR_EVENT`.
@@ -362,58 +333,9 @@ impl<'a> Iterator for EventLogIter<'a> {
 ///
 /// The corresponding C type is `EFI_TCG_PROTOCOL`.
 #[derive(Debug)]
-#[repr(C)]
-#[unsafe_protocol("f541796d-a62e-4954-a775-9584f61b9cdd")]
-pub struct Tcg {
-    status_check: unsafe extern "efiapi" fn(
-        this: *mut Tcg,
-        protocol_capability: *mut BootServiceCapability,
-        feature_flags: *mut u32,
-        event_log_location: *mut PhysicalAddress,
-        event_log_last_entry: *mut PhysicalAddress,
-    ) -> Status,
-
-    // Note: we do not currently expose this function because the spec
-    // for this is not well written. The function allocates memory, but
-    // the spec doesn't say how to free it. Most likely
-    // `EFI_BOOT_SERVICES.FreePool` would work, but this is not
-    // mentioned in the spec so it is unsafe to rely on.
-    //
-    // Also, this function is not that useful in practice for a couple
-    // reasons. First, it takes an algorithm ID, but only SHA-1 is
-    // supported with TPM v1. Second, TPMs are not cryptographic
-    // accelerators, so it is very likely faster to calculate the hash
-    // on the CPU, e.g. with the `sha1` crate.
-    hash_all: unsafe extern "efiapi" fn() -> Status,
-
-    log_event: unsafe extern "efiapi" fn(
-        this: *mut Tcg,
-        // The spec does not guarantee that the `event` will not be mutated
-        // through the pointer, but it seems reasonable to assume and makes the
-        // public interface clearer, so use a const pointer.
-        event: *const FfiPcrEvent,
-        event_number: *mut u32,
-        flags: u32,
-    ) -> Status,
-
-    pass_through_to_tpm: unsafe extern "efiapi" fn(
-        this: *mut Tcg,
-        tpm_input_parameter_block_size: u32,
-        tpm_input_parameter_block: *const u8,
-        tpm_output_parameter_block_size: u32,
-        tpm_output_parameter_block: *mut u8,
-    ) -> Status,
-
-    hash_log_extend_event: unsafe extern "efiapi" fn(
-        this: *mut Tcg,
-        hash_data: PhysicalAddress,
-        hash_data_len: u64,
-        algorithm_id: TCG_ALGORITHM_ID,
-        event: *mut FfiPcrEvent,
-        event_number: *mut u32,
-        event_log_last_entry: *mut PhysicalAddress,
-    ) -> Status,
-}
+#[repr(transparent)]
+#[unsafe_protocol(TcgProtocol::GUID)]
+pub struct Tcg(TcgProtocol);
 
 /// Return type of [`Tcg::status_check`].
 #[derive(Debug)]
@@ -433,14 +355,14 @@ impl Tcg {
     /// Get information about the protocol and TPM device, as well as
     /// the TPM event log.
     pub fn status_check(&mut self) -> Result<StatusCheck> {
-        let mut protocol_capability = BootServiceCapability::default();
+        let mut protocol_capability = TcgBootServiceCapability::default();
         let mut feature_flags = 0;
         let mut event_log_location = 0;
         let mut event_log_last_entry = 0;
 
         let status = unsafe {
-            (self.status_check)(
-                self,
+            (self.0.status_check)(
+                &mut self.0,
                 &mut protocol_capability,
                 &mut feature_flags,
                 &mut event_log_location,
@@ -461,7 +383,7 @@ impl Tcg {
             };
 
             Ok(StatusCheck {
-                protocol_capability,
+                protocol_capability: BootServiceCapability(protocol_capability),
                 feature_flags,
                 event_log,
             })
@@ -487,7 +409,9 @@ impl Tcg {
 
         let event_ptr: *const PcrEvent = event;
 
-        unsafe { (self.log_event)(self, event_ptr.cast(), &mut event_number, flags).to_result() }
+        unsafe {
+            (self.0.log_event)(&mut self.0, event_ptr.cast(), &mut event_number, flags).to_result()
+        }
     }
 
     /// Extend a PCR and add an entry to the event log.
@@ -517,8 +441,8 @@ impl Tcg {
         let event_ptr: *mut PcrEvent = event;
 
         unsafe {
-            (self.hash_log_extend_event)(
-                self,
+            (self.0.hash_log_extend_event)(
+                &mut self.0,
                 hash_data,
                 hash_data_len,
                 AlgorithmId::SHA1.0.into(),
@@ -550,8 +474,8 @@ impl Tcg {
             .map_err(|_| Error::from(Status::BAD_BUFFER_SIZE))?;
 
         unsafe {
-            (self.pass_through_to_tpm)(
-                self,
+            (self.0.pass_through_to_tpm)(
+                &mut self.0,
                 input_parameter_block_len,
                 input_parameter_block.as_ptr(),
                 output_parameter_block_len,