Add support for Magisk v27.0

Upstream Magisk now xz-compresses files in modifies in the ramdisk. This
commit also implements the same in avbroot's MagiskRootPatcher.

Signed-off-by: Andrew Gunnerson <accounts+github@chiller3.com>

avbroot/src/patch/boot.rs

@@ -140,10 +140,13 @@ impl MagiskRootPatcher {
     //   RULESDEVICE config option, which stored the writable block device as an
     //   rdev major/minor pair, which was not consistent across reboots and was
     //   replaced by PREINITDEVICE
-    const VERS_SUPPORTED: &'static [Range<u32>] = &[25102..25207, 25211..26500];
+    const VERS_SUPPORTED: &'static [Range<u32>] = &[25102..25207, 25211..27100];
     const VER_PREINIT_DEVICE: Range<u32> =
         25211..Self::VERS_SUPPORTED[Self::VERS_SUPPORTED.len() - 1].end;
     const VER_RANDOM_SEED: Range<u32> = 25211..26103;
+    const VER_PATCH_VBMETA: Range<u32> = Self::VERS_SUPPORTED[0].start..26202;
+    const VER_XZ_BACKUP: Range<u32> =
+        26403..Self::VERS_SUPPORTED[Self::VERS_SUPPORTED.len() - 1].end;
 
     pub fn new(
         path: &Path,
@@ -216,6 +219,18 @@ impl MagiskRootPatcher {
         }
     }
 
+    fn xz_compress(reader: impl Read, cancel_signal: &AtomicBool) -> Result<Vec<u8>> {
+        let stream = Stream::new_easy_encoder(9, Check::Crc32)?;
+        let raw_writer = Cursor::new(Vec::new());
+        let mut writer = XzEncoder::new_stream(raw_writer, stream);
+
+        stream::copy(reader, &mut writer, cancel_signal)?;
+
+        let raw_writer = writer.finish()?;
+
+        Ok(raw_writer.into_inner())
+    }
+
     /// Compare old and new ramdisk entry lists, creating the Magisk `.backup/`
     /// directory structure. `.backup/.rmlist` will contain a sorted list of
     /// NULL-terminated strings, listing which files were newly added or
@@ -223,7 +238,12 @@ impl MagiskRootPatcher {
     /// entries as `.backup/<path>`.
     ///
     /// Both lists and entries within the lists may be mutated.
-    fn apply_magisk_backup(old_entries: &mut [CpioEntry], new_entries: &mut Vec<CpioEntry>) {
+    fn apply_magisk_backup(
+        old_entries: &mut [CpioEntry],
+        new_entries: &mut Vec<CpioEntry>,
+        xz_compress: bool,
+        cancel_signal: &AtomicBool,
+    ) -> Result<()> {
         cpio::sort(old_entries);
         cpio::sort(new_entries);
 
@@ -269,10 +289,37 @@ impl MagiskRootPatcher {
         new_entries.push(CpioEntry::new_directory(b".backup", 0));
 
         for old_entry in to_back_up {
-            let mut new_entry = old_entry.clone();
-            new_entry.path = b".backup/".to_vec();
-            new_entry.path.extend(&old_entry.path);
-            new_entries.push(new_entry);
+            let mut new_path = b".backup/".to_vec();
+            new_path.extend(&old_entry.path);
+
+            let mut new_data = None;
+
+            if xz_compress {
+                if let CpioEntryData::Data(data) = &old_entry.data {
+                    new_path.extend(b".xz");
+
+                    let reader = Cursor::new(data);
+                    let buf = Self::xz_compress(reader, cancel_signal)?;
+                    new_data = Some(CpioEntryData::Data(buf));
+                }
+            }
+
+            new_entries.push(CpioEntry {
+                path: new_path,
+                data: new_data.unwrap_or_else(|| old_entry.data.clone()),
+                inode: old_entry.inode,
+                file_type: old_entry.file_type,
+                file_mode: old_entry.file_mode,
+                uid: old_entry.uid,
+                gid: old_entry.gid,
+                nlink: old_entry.nlink,
+                mtime: old_entry.mtime,
+                dev_maj: old_entry.dev_maj,
+                dev_min: old_entry.dev_min,
+                rdev_maj: old_entry.rdev_maj,
+                rdev_min: old_entry.rdev_min,
+                crc32: old_entry.crc32,
+            });
         }
 
         new_entries.push(CpioEntry::new_file(
@@ -280,6 +327,8 @@ impl MagiskRootPatcher {
             0,
             CpioEntryData::Data(rm_list),
         ));
+
+        Ok(())
     }
 }
 
@@ -347,7 +396,9 @@ impl BootImagePatch for MagiskRootPatcher {
             ));
         }
 
-        // Add xz-compressed magisk32 and magisk64.
+        // Add xz-compressed magisk32 and magisk64. We currently unconditionally
+        // include magisk32 because the boot image itself doesn't contain
+        // sufficient information to determine if a device is 64-bit only.
         let mut xz_files = HashMap::<&str, &[u8]>::new();
         xz_files.insert(
             "lib/armeabi-v7a/libmagisk32.so",
@@ -366,29 +417,28 @@ impl BootImagePatch for MagiskRootPatcher {
 
         for (source, target) in xz_files {
             let reader = zip.by_name(source)?;
-            let raw_writer = Cursor::new(vec![]);
-            let stream = Stream::new_easy_encoder(9, Check::Crc32)?;
-            let mut writer = XzEncoder::new_stream(raw_writer, stream);
+            let buf = Self::xz_compress(reader, cancel_signal)?;
 
-            stream::copy(reader, &mut writer, cancel_signal)?;
-
-            let raw_writer = writer.finish()?;
-
-            entries.push(CpioEntry::new_file(
-                target,
-                0o644,
-                CpioEntryData::Data(raw_writer.into_inner()),
-            ));
+            entries.push(CpioEntry::new_file(target, 0o644, CpioEntryData::Data(buf)));
         }
 
         // Create Magisk .backup directory structure.
-        Self::apply_magisk_backup(&mut old_entries, &mut entries);
+        Self::apply_magisk_backup(
+            &mut old_entries,
+            &mut entries,
+            Self::VER_XZ_BACKUP.contains(&self.version),
+            cancel_signal,
+        )?;
 
         // Create Magisk config.
         let mut magisk_config = String::new();
         magisk_config.push_str("KEEPVERITY=true\n");
         magisk_config.push_str("KEEPFORCEENCRYPT=true\n");
-        magisk_config.push_str("PATCHVBMETAFLAG=false\n");
+
+        if Self::VER_PATCH_VBMETA.contains(&self.version) {
+            magisk_config.push_str("PATCHVBMETAFLAG=false\n");
+        }
+
         magisk_config.push_str("RECOVERYMODE=false\n");
 
         if Self::VER_PREINIT_DEVICE.contains(&self.version) {

e2e/e2e.toml

@@ -47,7 +47,7 @@ data.ramdisks = ["otacerts"]
 
 [profile.pixel_v4_gki.hashes]
 original = "f9477a35e3b60a495e49431c61e3897f11775f453a6a9897ead568357c963618"
-patched = "eb045799a514300727357a5ec471f9b04b276991daf4fd72f17f840b2a7dd1b8"
+patched = "d3436650b4e0c60688dafb1472fa5fe95e67d19a8fad2da4850ffaa739d44574"
 
 # Google Pixel 6a
 # What's unique: boot (boot v4, no ramdisk) + vendor_boot (vendor v4, 2 ramdisks)
@@ -81,7 +81,7 @@ data.ramdisks = ["init_and_otacerts", "dlkm"]
 
 [profile.pixel_v4_non_gki.hashes]
 original = "021b4510bc244f5f686fbff89eb2058ec9c96a2949c2fe8caa7750a78d593225"
-patched = "5d1a36e2eb18d9d905ab397d4eaf2d7e7c94da6e7573afe3d4e4367841171fe3"
+patched = "0f90ae4c26a54a735d48e13e98bea73b6d1c026b0e95fa5b4b26179a1d6bdc86"
 
 # Google Pixel 4a 5G
 # What's unique: boot (boot v3) + vendor_boot (vendor v3)
@@ -116,7 +116,7 @@ data.ramdisks = ["otacerts"]
 
 [profile.pixel_v3.hashes]
 original = "12221a69ff32e137d5f19b61f576fc6b33f0973c4a81da7722c640554ff4bc4e"
-patched = "e2049c6eba6990fc5ce30130af470c134a5ccc42947dcdd398f737fbca7ae44a"
+patched = "0a92969bbd7cb30071a0799eb20028546d1cec3e6ec1ca4d7e1fe7776f1399fc"
 
 # Google Pixel 4a
 # What's unique: boot (boot v2)
@@ -145,4 +145,4 @@ data.deps = ["system"]
 
 [profile.pixel_v2.hashes]
 original = "8b38d2d999b5b6e240e894f669e9e2643b3764c108d53bb7b02447da725e7c18"
-patched = "16f56e3d02c08bb646d8d0694ce77a6edb02a613bbcff14b10ead4a448c3dc00"
+patched = "85b411947145e89cdc7f71b7109a12586f4dbddce3021f0f96172fc465c189d6"

e2e/src/main.rs

@@ -817,11 +817,12 @@ fn create_fake_magisk(output: &Path) -> Result<()> {
         "lib/x86_64/libmagiskinit.so",
     ] {
         zip_writer.start_file(path, FileOptions::default())?;
+        write!(zip_writer, "dummy contents for {path}")?;
     }
 
     // avbroot looks for the version number in this file.
     zip_writer.start_file("assets/util_functions.sh", FileOptions::default())?;
-    zip_writer.write_all(b"MAGISK_VER_CODE=26400\n")?;
+    zip_writer.write_all(b"MAGISK_VER_CODE=27000\n")?;
 
     Ok(())
 }