[avb] Refactor Payload and AvbOps into new module ops
Bug: 256148034
Test: m pvmfw_img && atest libpvmfw_avb.integration_test
Change-Id: I001be824245dd1ea01ee01868ed4dbbfb37b86c6
diff --git a/pvmfw/avb/src/verify.rs b/pvmfw/avb/src/verify.rs
index b39bb5a..d6a0cb2 100644
--- a/pvmfw/avb/src/verify.rs
+++ b/pvmfw/avb/src/verify.rs
@@ -14,24 +14,20 @@
//! This module handles the pvmfw payload verification.
-use crate::error::{
- slot_verify_result_to_verify_payload_result, to_avb_io_result, AvbIOError, AvbSlotVerifyError,
-};
+use crate::error::{AvbIOError, AvbSlotVerifyError};
+use crate::ops::{Ops, Payload};
use crate::partition::PartitionName;
-use crate::utils::{as_ref, is_not_null, to_nonnull, to_usize, usize_checked_add, write};
+use crate::utils::{is_not_null, to_usize, usize_checked_add, write};
use avb_bindgen::{
- avb_descriptor_foreach, avb_hash_descriptor_validate_and_byteswap, avb_slot_verify,
- avb_slot_verify_data_free, AvbDescriptor, AvbHashDescriptor, AvbHashtreeErrorMode, AvbIOResult,
- AvbOps, AvbSlotVerifyData, AvbSlotVerifyFlags, AvbVBMetaData,
+ avb_descriptor_foreach, avb_hash_descriptor_validate_and_byteswap, AvbDescriptor,
+ AvbHashDescriptor, AvbVBMetaData,
};
use core::{
- ffi::{c_char, c_void, CStr},
+ ffi::{c_char, c_void},
mem::{size_of, MaybeUninit},
- ptr, slice,
+ slice,
};
-const NULL_BYTE: &[u8] = b"\0";
-
/// This enum corresponds to the `DebugLevel` in `VirtualMachineConfig`.
#[derive(Clone, Debug, PartialEq, Eq)]
pub enum DebugLevel {
@@ -41,167 +37,6 @@
Full,
}
-extern "C" fn read_is_device_unlocked(
- _ops: *mut AvbOps,
- out_is_unlocked: *mut bool,
-) -> AvbIOResult {
- to_avb_io_result(write(out_is_unlocked, false))
-}
-
-extern "C" fn get_preloaded_partition(
- ops: *mut AvbOps,
- partition: *const c_char,
- num_bytes: usize,
- out_pointer: *mut *mut u8,
- out_num_bytes_preloaded: *mut usize,
-) -> AvbIOResult {
- to_avb_io_result(try_get_preloaded_partition(
- ops,
- partition,
- num_bytes,
- out_pointer,
- out_num_bytes_preloaded,
- ))
-}
-
-fn try_get_preloaded_partition(
- ops: *mut AvbOps,
- partition: *const c_char,
- num_bytes: usize,
- out_pointer: *mut *mut u8,
- out_num_bytes_preloaded: *mut usize,
-) -> Result<(), AvbIOError> {
- let ops = as_ref(ops)?;
- let partition = ops.as_ref().get_partition(partition)?;
- write(out_pointer, partition.as_ptr() as *mut u8)?;
- write(out_num_bytes_preloaded, partition.len().min(num_bytes))
-}
-
-extern "C" fn read_from_partition(
- ops: *mut AvbOps,
- partition: *const c_char,
- offset: i64,
- num_bytes: usize,
- buffer: *mut c_void,
- out_num_read: *mut usize,
-) -> AvbIOResult {
- to_avb_io_result(try_read_from_partition(
- ops,
- partition,
- offset,
- num_bytes,
- buffer,
- out_num_read,
- ))
-}
-
-fn try_read_from_partition(
- ops: *mut AvbOps,
- partition: *const c_char,
- offset: i64,
- num_bytes: usize,
- buffer: *mut c_void,
- out_num_read: *mut usize,
-) -> Result<(), AvbIOError> {
- let ops = as_ref(ops)?;
- let partition = ops.as_ref().get_partition(partition)?;
- let buffer = to_nonnull(buffer)?;
- // SAFETY: It is safe to copy the requested number of bytes to `buffer` as `buffer`
- // is created to point to the `num_bytes` of bytes in memory.
- let buffer_slice = unsafe { slice::from_raw_parts_mut(buffer.as_ptr() as *mut u8, num_bytes) };
- copy_data_to_dst(partition, offset, buffer_slice)?;
- write(out_num_read, buffer_slice.len())
-}
-
-fn copy_data_to_dst(src: &[u8], offset: i64, dst: &mut [u8]) -> Result<(), AvbIOError> {
- let start = to_copy_start(offset, src.len()).ok_or(AvbIOError::InvalidValueSize)?;
- let end = start.checked_add(dst.len()).ok_or(AvbIOError::InvalidValueSize)?;
- dst.copy_from_slice(src.get(start..end).ok_or(AvbIOError::RangeOutsidePartition)?);
- Ok(())
-}
-
-fn to_copy_start(offset: i64, len: usize) -> Option<usize> {
- usize::try_from(offset)
- .ok()
- .or_else(|| isize::try_from(offset).ok().and_then(|v| len.checked_add_signed(v)))
-}
-
-extern "C" fn get_size_of_partition(
- ops: *mut AvbOps,
- partition: *const c_char,
- out_size_num_bytes: *mut u64,
-) -> AvbIOResult {
- to_avb_io_result(try_get_size_of_partition(ops, partition, out_size_num_bytes))
-}
-
-fn try_get_size_of_partition(
- ops: *mut AvbOps,
- partition: *const c_char,
- out_size_num_bytes: *mut u64,
-) -> Result<(), AvbIOError> {
- let ops = as_ref(ops)?;
- let partition = ops.as_ref().get_partition(partition)?;
- let partition_size =
- u64::try_from(partition.len()).map_err(|_| AvbIOError::InvalidValueSize)?;
- write(out_size_num_bytes, partition_size)
-}
-
-extern "C" fn read_rollback_index(
- _ops: *mut AvbOps,
- _rollback_index_location: usize,
- _out_rollback_index: *mut u64,
-) -> AvbIOResult {
- // Rollback protection is not yet implemented, but
- // this method is required by `avb_slot_verify()`.
- AvbIOResult::AVB_IO_RESULT_OK
-}
-
-extern "C" fn get_unique_guid_for_partition(
- _ops: *mut AvbOps,
- _partition: *const c_char,
- _guid_buf: *mut c_char,
- _guid_buf_size: usize,
-) -> AvbIOResult {
- // This method is required by `avb_slot_verify()`.
- AvbIOResult::AVB_IO_RESULT_OK
-}
-
-extern "C" fn validate_vbmeta_public_key(
- ops: *mut AvbOps,
- public_key_data: *const u8,
- public_key_length: usize,
- public_key_metadata: *const u8,
- public_key_metadata_length: usize,
- out_is_trusted: *mut bool,
-) -> AvbIOResult {
- to_avb_io_result(try_validate_vbmeta_public_key(
- ops,
- public_key_data,
- public_key_length,
- public_key_metadata,
- public_key_metadata_length,
- out_is_trusted,
- ))
-}
-
-fn try_validate_vbmeta_public_key(
- ops: *mut AvbOps,
- public_key_data: *const u8,
- public_key_length: usize,
- _public_key_metadata: *const u8,
- _public_key_metadata_length: usize,
- out_is_trusted: *mut bool,
-) -> Result<(), AvbIOError> {
- is_not_null(public_key_data)?;
- // SAFETY: It is safe to create a slice with the given pointer and length as
- // `public_key_data` is a valid pointer and it points to an array of length
- // `public_key_length`.
- let public_key = unsafe { slice::from_raw_parts(public_key_data, public_key_length) };
- let ops = as_ref(ops)?;
- let trusted_public_key = ops.as_ref().trusted_public_key;
- write(out_is_trusted, public_key == trusted_public_key)
-}
-
extern "C" fn search_initrd_hash_descriptor(
descriptor: *const AvbDescriptor,
user_data: *mut c_void,
@@ -277,119 +112,6 @@
}
}
-struct AvbSlotVerifyDataWrap(*mut AvbSlotVerifyData);
-
-impl TryFrom<*mut AvbSlotVerifyData> for AvbSlotVerifyDataWrap {
- type Error = AvbSlotVerifyError;
-
- fn try_from(data: *mut AvbSlotVerifyData) -> Result<Self, Self::Error> {
- is_not_null(data).map_err(|_| AvbSlotVerifyError::Io)?;
- Ok(Self(data))
- }
-}
-
-impl Drop for AvbSlotVerifyDataWrap {
- fn drop(&mut self) {
- // SAFETY: This is safe because `self.0` is checked nonnull when the
- // instance is created. We can free this pointer when the instance is
- // no longer needed.
- unsafe {
- avb_slot_verify_data_free(self.0);
- }
- }
-}
-
-impl AsRef<AvbSlotVerifyData> for AvbSlotVerifyDataWrap {
- fn as_ref(&self) -> &AvbSlotVerifyData {
- // This is safe because `self.0` is checked nonnull when the instance is created.
- as_ref(self.0).unwrap()
- }
-}
-
-impl AvbSlotVerifyDataWrap {
- fn vbmeta_images(&self) -> Result<&[AvbVBMetaData], AvbSlotVerifyError> {
- let data = self.as_ref();
- is_not_null(data.vbmeta_images).map_err(|_| AvbSlotVerifyError::Io)?;
- // SAFETY: It is safe as the raw pointer `data.vbmeta_images` is a nonnull pointer.
- let vbmeta_images =
- unsafe { slice::from_raw_parts(data.vbmeta_images, data.num_vbmeta_images) };
- Ok(vbmeta_images)
- }
-}
-
-struct Payload<'a> {
- kernel: &'a [u8],
- initrd: Option<&'a [u8]>,
- trusted_public_key: &'a [u8],
-}
-
-impl<'a> AsRef<Payload<'a>> for AvbOps {
- fn as_ref(&self) -> &Payload<'a> {
- let payload = self.user_data as *const Payload;
- // SAFETY: It is safe to cast the `AvbOps.user_data` to Payload as we have saved a
- // pointer to a valid value of Payload in user_data when creating AvbOps, and
- // assume that the Payload isn't used beyond the lifetime of the AvbOps that it
- // belongs to.
- unsafe { &*payload }
- }
-}
-
-impl<'a> Payload<'a> {
- fn get_partition(&self, partition_name: *const c_char) -> Result<&[u8], AvbIOError> {
- match partition_name.try_into()? {
- PartitionName::Kernel => Ok(self.kernel),
- PartitionName::InitrdNormal | PartitionName::InitrdDebug => {
- self.initrd.ok_or(AvbIOError::NoSuchPartition)
- }
- }
- }
-
- fn verify_partition(
- &mut self,
- partition_name: &CStr,
- ) -> Result<AvbSlotVerifyDataWrap, AvbSlotVerifyError> {
- let requested_partitions = [partition_name.as_ptr(), ptr::null()];
- let mut avb_ops = AvbOps {
- user_data: self as *mut _ as *mut c_void,
- ab_ops: ptr::null_mut(),
- atx_ops: ptr::null_mut(),
- read_from_partition: Some(read_from_partition),
- get_preloaded_partition: Some(get_preloaded_partition),
- write_to_partition: None,
- validate_vbmeta_public_key: Some(validate_vbmeta_public_key),
- read_rollback_index: Some(read_rollback_index),
- write_rollback_index: None,
- read_is_device_unlocked: Some(read_is_device_unlocked),
- get_unique_guid_for_partition: Some(get_unique_guid_for_partition),
- get_size_of_partition: Some(get_size_of_partition),
- read_persistent_value: None,
- write_persistent_value: None,
- validate_public_key_for_partition: None,
- };
- let ab_suffix = CStr::from_bytes_with_nul(NULL_BYTE).unwrap();
- let mut out_data = MaybeUninit::uninit();
- // SAFETY: It is safe to call `avb_slot_verify()` as the pointer arguments (`ops`,
- // `requested_partitions` and `ab_suffix`) passed to the method are all valid and
- // initialized. The last argument `out_data` is allowed to be null so that nothing
- // will be written to it.
- let result = unsafe {
- avb_slot_verify(
- &mut avb_ops,
- requested_partitions.as_ptr(),
- ab_suffix.as_ptr(),
- AvbSlotVerifyFlags::AVB_SLOT_VERIFY_FLAGS_NONE,
- AvbHashtreeErrorMode::AVB_HASHTREE_ERROR_MODE_RESTART_AND_INVALIDATE,
- out_data.as_mut_ptr(),
- )
- };
- slot_verify_result_to_verify_payload_result(result)?;
- // SAFETY: This is safe because `out_data` has been properly initialized after
- // calling `avb_slot_verify` and it returns OK.
- let out_data = unsafe { out_data.assume_init() };
- out_data.try_into()
- }
-}
-
fn verify_vbmeta_has_no_initrd_descriptor(
vbmeta_image: &AvbVBMetaData,
) -> Result<(), AvbSlotVerifyError> {
@@ -428,8 +150,9 @@
initrd: Option<&[u8]>,
trusted_public_key: &[u8],
) -> Result<DebugLevel, AvbSlotVerifyError> {
- let mut payload = Payload { kernel, initrd, trusted_public_key };
- let kernel_verify_result = payload.verify_partition(PartitionName::Kernel.as_cstr())?;
+ let mut payload = Payload::new(kernel, initrd, trusted_public_key);
+ let mut ops = Ops::from(&mut payload);
+ let kernel_verify_result = ops.verify_partition(PartitionName::Kernel.as_cstr())?;
let vbmeta_images = kernel_verify_result.vbmeta_images()?;
if vbmeta_images.len() != 1 {
// There can only be one VBMeta.
@@ -437,16 +160,16 @@
}
let vbmeta_image = vbmeta_images[0];
verify_vbmeta_is_from_kernel_partition(&vbmeta_image)?;
- if payload.initrd.is_none() {
+ if initrd.is_none() {
verify_vbmeta_has_no_initrd_descriptor(&vbmeta_image)?;
return Ok(DebugLevel::None);
}
// TODO(b/256148034): Check the vbmeta doesn't have hash descriptors other than
// boot, initrd_normal, initrd_debug.
- let debug_level = if payload.verify_partition(PartitionName::InitrdNormal.as_cstr()).is_ok() {
+ let debug_level = if ops.verify_partition(PartitionName::InitrdNormal.as_cstr()).is_ok() {
DebugLevel::None
- } else if payload.verify_partition(PartitionName::InitrdDebug.as_cstr()).is_ok() {
+ } else if ops.verify_partition(PartitionName::InitrdDebug.as_cstr()).is_ok() {
DebugLevel::Full
} else {
return Err(AvbSlotVerifyError::Verification);