Do not use size filler
instead always fill zeros when there's gap between composite disk
components.
Bug: 192991318
Test: MicrodroidHostTestCases
Change-Id: I89234e047b6d5a48fee773dac0e7971ab465242c
diff --git a/virtualizationservice/src/payload.rs b/virtualizationservice/src/payload.rs
index 1df537c..9c6deae 100644
--- a/virtualizationservice/src/payload.rs
+++ b/virtualizationservice/src/payload.rs
@@ -14,17 +14,13 @@
//! Payload disk image
-use crate::composite::align_to_partition_size;
-
use anyhow::{anyhow, Context, Result};
use microdroid_metadata::{ApexPayload, ApkPayload, Metadata};
use microdroid_payload_config::ApexConfig;
use once_cell::sync::OnceCell;
use serde::Deserialize;
use serde_xml_rs::from_reader;
-use std::fs;
use std::fs::{File, OpenOptions};
-use std::io::{Seek, SeekFrom, Write};
use std::path::{Path, PathBuf};
use vmconfig::{DiskImage, Partition};
@@ -69,46 +65,12 @@
}
}
-/// When passing a host APEX file as a block device in a payload disk image,
-/// the size of the original file needs to be stored in the last 4 bytes so that
-/// other programs (e.g. apexd) can read it as a zip.
-/// Returns true always since the filler is created.
-fn make_size_filler(size: u64, filler_path: &Path) -> Result<bool> {
- let partition_size = align_to_partition_size(size + 4);
- let mut file = OpenOptions::new().create_new(true).write(true).open(filler_path)?;
- file.set_len(partition_size - size)?;
- file.seek(SeekFrom::End(-4))?;
- file.write_all(&(size as i32).to_be_bytes())?;
- Ok(true)
-}
-
-/// When passing a host APK file as a block device in a payload disk image and it is
-/// mounted via dm-verity, we need to make the device zero-padded up to 4K boundary.
-/// Otherwise, integrity checks via hashtree will fail.
-/// Returns true if filler is created.
-fn make_zero_filler(size: u64, filler_path: &Path) -> Result<bool> {
- let partition_size = align_to_partition_size(size);
- if partition_size <= size {
- return Ok(false);
- }
- let file = OpenOptions::new().create_new(true).write(true).open(filler_path)?;
- file.set_len(partition_size - size)?;
- Ok(true)
-}
-
-/// When passing a host idsig file as a block device, we don't need any filler because it is read
-/// in length-prefixed way.
-/// Returns false always because the filler is not created.
-fn make_no_filler(_size: u64, _filler_path: &Path) -> Result<bool> {
- Ok(false)
-}
-
/// Creates a DiskImage with partitions:
/// metadata: metadata
-/// microdroid-apex-0: [apex 0, size filler]
-/// microdroid-apex-1: [apex 1, size filler]
+/// microdroid-apex-0: apex 0
+/// microdroid-apex-1: apex 1
/// ..
-/// microdroid-apk: [apk, zero filler]
+/// microdroid-apk: apk
/// microdroid-apk-idsig: idsig
pub fn make_payload_disk(
apk_file: PathBuf,
@@ -146,48 +108,23 @@
}];
let apex_info_list = ApexInfoList::load()?;
- let mut filler_count = 0;
for (i, apex) in apexes.iter().enumerate() {
- partitions.push(make_partition(
- format!("microdroid-apex-{}", i),
- apex_info_list.get_path_for(&apex.name)?,
- temporary_directory,
- &mut filler_count,
- &make_size_filler,
- )?);
+ partitions.push(Partition {
+ label: format!("microdroid-apex-{}", i),
+ paths: vec![apex_info_list.get_path_for(&apex.name)?],
+ writable: false,
+ });
}
- partitions.push(make_partition(
- "microdroid-apk".to_owned(),
- apk_file,
- temporary_directory,
- &mut filler_count,
- &make_zero_filler,
- )?);
- partitions.push(make_partition(
- "microdroid-apk-idsig".to_owned(),
- idsig_file,
- temporary_directory,
- &mut filler_count,
- &make_no_filler,
- )?);
+ partitions.push(Partition {
+ label: "microdroid-apk".to_owned(),
+ paths: vec![apk_file],
+ writable: false,
+ });
+ partitions.push(Partition {
+ label: "microdroid-apk-idsig".to_owned(),
+ paths: vec![idsig_file],
+ writable: false,
+ });
Ok(DiskImage { image: None, partitions, writable: false })
}
-
-fn make_partition(
- label: String,
- path: PathBuf,
- temporary_directory: &Path,
- filler_count: &mut u32,
- make_filler: &dyn Fn(u64, &Path) -> Result<bool>,
-) -> Result<Partition> {
- let filler_path = temporary_directory.join(format!("filler-{}", filler_count));
- let size = fs::metadata(&path)?.len();
-
- if make_filler(size, &filler_path)? {
- *filler_count += 1;
- Ok(Partition { label, paths: vec![path, filler_path], writable: false })
- } else {
- Ok(Partition { label, paths: vec![path], writable: false })
- }
-}