ksud: make it compilable for non-android

userspace/ksud/Cargo.lock

@@ -1032,9 +1032,9 @@ dependencies = [
 
 [[package]]
 name = "sys-mount"
-version = "2.0.1"
+version = "2.0.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "793d38aa916d55e979587ea7cf551106f5f091e548a91e89ee4f0698bc9cf289"
+checksum = "d8b080a2fff4d267282506b4d5f2efe0dfa732fb2a5715f30662eed1c4f13390"
 dependencies = [
  "bitflags",
  "libc",

userspace/ksud/Cargo.toml

@@ -22,14 +22,16 @@ encoding = "0.2.33"
 retry = "2.0.0"
 humansize = "2.0.0"
 libc = "0.2"
-sys-mount = "2.0.1"
-android-properties = { version = "0.2.2", features = ["bionic-deprecated"] }
 extattr = "1.0.0"
 jwalk = "0.8.1"
 is_executable = "1.0.1"
 nom = "7"
 derive-new = "0.5"
 
+[target.'cfg(target_os = "android")'.dependencies]
+sys-mount = "2.0.1"
+android-properties = { version = "0.2.2", features = ["bionic-deprecated"] }
+
 [profile.release]
 strip = true
 opt-level = "z"

userspace/ksud/src/apk_sign.rs

@@ -23,7 +23,7 @@ pub fn get_apk_signature(apk: &str) -> Result<(u32, u32)> {
 
             if u32::from_le_bytes(size4) ^ 0xcafebabeu32 == 0xccfbf1eeu32 {
                 if i > 0 {
-                    println!("warning: comment length is {}", i);
+                    println!("warning: comment length is {i}");
                 }
                 break;
             }

userspace/ksud/src/event.rs

@@ -1,22 +1,21 @@
 use std::{collections::HashMap, path::Path};
 
 use crate::{
-    assets, defs,
-    utils::{ensure_clean_dir, ensure_dir_exists, mount_image},
+    assets, defs, mount,
+    utils::{ensure_clean_dir, ensure_dir_exists},
 };
 use anyhow::{bail, Context, Result};
-use sys_mount::{FilesystemType, Mount, MountFlags};
 
-fn mount_partition(partition: &str, lowerdir: &mut Vec<String>) {
+fn mount_partition(partition: &str, lowerdir: &mut Vec<String>) -> Result<()> {
     if lowerdir.is_empty() {
         println!("partition: {partition} lowerdir is empty");
-        return;
+        return Ok(());
     }
 
     // if /partition is a symlink and linked to /system/partition, then we don't need to overlay it separately
     if Path::new(&format!("/{}", partition)).read_link().is_ok() {
         println!("partition: {} is a symlink", partition);
-        return;
+        return Ok(());
     }
     // add /partition as the lowerest dir
     let lowest_dir = format!("/{partition}");
@@ -25,14 +24,7 @@ fn mount_partition(partition: &str, lowerdir: &mut Vec<String>) {
     let lowerdir = lowerdir.join(":");
     println!("partition: {partition} lowerdir: {lowerdir}");
 
-    if let Err(err) = Mount::builder()
-        .fstype(FilesystemType::from("overlay"))
-        .flags(MountFlags::RDONLY)
-        .data(&format!("lowerdir={lowerdir}"))
-        .mount("overlay", lowest_dir)
-    {
-        println!("mount partition: {partition} overlay failed: {err}");
-    }
+    mount::mount_overlay(&lowerdir, &lowest_dir)
 }
 
 pub fn do_systemless_mount(module_dir: &str) -> Result<()> {
@@ -82,11 +74,11 @@ pub fn do_systemless_mount(module_dir: &str) -> Result<()> {
     }
 
     // mount /system first
-    mount_partition("system", &mut system_lowerdir);
+    let _ = mount_partition("system", &mut system_lowerdir);
 
     // mount other partitions
     for (k, mut v) in partition_lowerdir {
-        mount_partition(&k, &mut v);
+        let _ = mount_partition(&k, &mut v);
     }
 
     Ok(())
@@ -127,7 +119,7 @@ pub fn on_post_data_fs() -> Result<()> {
     }
 
     println!("mount {} to {}", target_update_img, module_dir);
-    mount_image(target_update_img, module_dir)?;
+    mount::mount_ext4(target_update_img, module_dir)?;
 
     // load sepolicy.rule
     if crate::module::load_sepolicy_rule().is_err() {

userspace/ksud/src/main.rs

@@ -9,6 +9,7 @@ mod restorecon;
 mod utils;
 mod sepolicy;
 mod assets;
+mod mount;
 
 fn main() -> anyhow::Result<()> {
     cli::run()

userspace/ksud/src/module.rs

@@ -4,6 +4,7 @@ use crate::{
     sepolicy,
     utils::*,
     assets,
+    mount,
 };
 
 use const_format::concatcp;
@@ -430,7 +431,7 @@ pub fn install_module(zip: String) -> Result<()> {
     // mount the modules_update.img to mountpoint
     println!("- Mounting image");
 
-    mount_image(tmp_module_img, module_update_tmp_dir)?;
+    mount::mount_ext4(tmp_module_img, module_update_tmp_dir)?;
 
     setsyscon(module_update_tmp_dir)?;
 
@@ -457,7 +458,7 @@ pub fn install_module(zip: String) -> Result<()> {
     };
 
     // umount the modules_update.img
-    let _ = umount_dir(module_update_tmp_dir);
+    let _ = mount::umount_dir(module_update_tmp_dir);
 
     // remove modules_update dir, ignore the error
     let _ = remove_dir_all(module_update_tmp_dir);
@@ -506,13 +507,13 @@ where
     ensure_clean_dir(update_dir)?;
 
     // mount the modules_update img
-    mount_image(defs::MODULE_UPDATE_TMP_IMG, update_dir)?;
+    mount::mount_ext4(defs::MODULE_UPDATE_TMP_IMG, update_dir)?;
 
     // call the operation func
     let result = func(id, update_dir);
 
     // umount modules_update.img
-    let _ = umount_dir(update_dir);
+    let _ = mount::umount_dir(update_dir);
     let _ = remove_dir_all(update_dir);
 
     std::fs::rename(modules_update_tmp_img, defs::MODULE_UPDATE_IMG)?;

userspace/ksud/src/mount.rs

@@ -0,0 +1,58 @@
+use anyhow::Result;
+
+#[cfg(target_os = "android")]
+use anyhow::{ensure, Context, Ok};
+#[cfg(target_os = "android")]
+use retry::delay::NoDelay;
+#[cfg(target_os = "android")]
+use sys_mount::{unmount, FilesystemType, Mount, MountFlags, UnmountFlags};
+
+#[cfg(target_os = "android")]
+fn do_mount_image(src: &str, target: &str) -> Result<()> {
+    Mount::builder()
+        .fstype(FilesystemType::from("ext4"))
+        .mount(src, target)
+        .with_context(|| format!("Failed to do mount: {src} -> {target}"))?;
+    Ok(())
+}
+
+#[cfg(target_os = "android")]
+pub fn mount_ext4(src: &str, target: &str) -> Result<()> {
+    // umount target first.
+    let _ = umount_dir(target);
+    let result = retry::retry(NoDelay.take(3), || do_mount_image(src, target));
+    ensure!(result.is_ok(), "Failed to mount {} -> {}", src, target);
+    Ok(())
+}
+
+#[cfg(target_os = "android")]
+pub fn umount_dir(src: &str) -> Result<()> {
+    unmount(src, UnmountFlags::empty()).with_context(|| format!("Failed to umount {src}"))?;
+    Ok(())
+}
+
+#[cfg(target_os = "android")]
+pub fn mount_overlay(lowerdir: &str, mnt: &str) -> Result<()> {
+    Mount::builder()
+        .fstype(FilesystemType::from("overlay"))
+        .flags(MountFlags::RDONLY)
+        .data(&format!("lowerdir={lowerdir}"))
+        .mount("overlay", mnt)
+        .map(|_| ())
+        .map_err(|e| anyhow::anyhow!("mount partition: {mnt} overlay failed: {e}"))
+}
+
+#[cfg(not(target_os = "android"))]
+pub fn mount_ext4(src: &str, target: &str) -> Result<()> {
+    unimplemented!()
+}
+
+#[cfg(not(target_os = "android"))]
+pub fn umount_dir(src: &str) -> Result<()> {
+    unimplemented!()
+}
+
+#[cfg(not(target_os = "android"))]
+pub fn mount_overlay(lowerdir: &str, mnt: &str) -> Result<()> {
+    unimplemented!()
+}

userspace/ksud/src/restorecon.rs

@@ -1,4 +1,5 @@
 use anyhow::{Context, Ok, Result};
+#[cfg(target_os = "android")]
 use extattr::{setxattr, Flags as XattrFlags};
 use jwalk::{Parallelism::Serial, WalkDir};
 
@@ -6,6 +7,7 @@ const SYSTEM_CON: &str = "u:object_r:system_file:s0";
 const _ADB_CON: &str = "u:object_r:adb_data_file:s0";
 
 pub fn setcon(path: &str, con: &str) -> Result<()> {
+    #[cfg(target_os = "android")]
     setxattr(path, "security.selinux", con, XattrFlags::empty())
         .with_context(|| format!("Failed to change SELinux context for {path}"))?;
     Ok(())
@@ -18,6 +20,7 @@ pub fn setsyscon(path: &str) -> Result<()> {
 pub fn restore_syscon(dir: &str) -> Result<()> {
     for dir_entry in WalkDir::new(dir).parallelism(Serial) {
         if let Some(path) = dir_entry.ok().map(|dir_entry| dir_entry.path()) {
+            #[cfg(target_os = "android")]
             setxattr(&path, "security.selinux", SYSTEM_CON, XattrFlags::empty()).with_context(
                 || {
                     format!(

userspace/ksud/src/sepolicy.rs

@@ -11,7 +11,7 @@ use nom::{
     sequence::Tuple,
     IResult, Parser,
 };
-use std::{vec, path::Path};
+use std::{path::Path, vec};
 
 type SeObject<'a> = Vec<&'a str>;
 
@@ -692,6 +692,7 @@ impl From<AtomicStatement> for FfiPolicy {
     }
 }
 
+#[cfg(target_os = "android")]
 fn apply_one_rule<'a>(statement: &'a PolicyStatement<'a>) -> Result<()> {
     let policies: Vec<AtomicStatement> = statement.try_into()?;
 
@@ -716,6 +717,11 @@ fn apply_one_rule<'a>(statement: &'a PolicyStatement<'a>) -> Result<()> {
     Ok(())
 }
 
+#[cfg(not(target_os = "android"))]
+fn apply_one_rule<'a>(statement: &'a PolicyStatement<'a>) -> Result<()> {
+    unimplemented!()
+}
+
 pub fn live_patch(policy: &str) -> Result<()> {
     let result = parse_sepolicy(policy.trim())?;
     for statement in result {

userspace/ksud/src/utils.rs

@@ -1,33 +1,10 @@
-use anyhow::{bail, ensure, Context, Error, Ok, Result};
-use retry::delay::NoDelay;
+use anyhow::{bail, Context, Error, Ok, Result};
 use std::{
     fs::{create_dir_all, set_permissions, write, File, Permissions},
     io::ErrorKind::AlreadyExists,
     os::unix::prelude::PermissionsExt,
     path::Path,
 };
-use sys_mount::{unmount, FilesystemType, Mount, UnmountFlags};
-
-fn do_mount_image(src: &str, target: &str) -> Result<()> {
-    Mount::builder()
-        .fstype(FilesystemType::from("ext4"))
-        .mount(src, target)
-        .with_context(|| format!("Failed to do mount: {src} -> {target}"))?;
-    Ok(())
-}
-
-pub fn mount_image(src: &str, target: &str) -> Result<()> {
-    // umount target first.
-    let _ = umount_dir(target);
-    let result = retry::retry(NoDelay.take(3), || do_mount_image(src, target));
-    ensure!(result.is_ok(), "Failed to mount {} -> {}", src, target);
-    Ok(())
-}
-
-pub fn umount_dir(src: &str) -> Result<()> {
-    unmount(src, UnmountFlags::empty()).with_context(|| format!("Failed to umount {src}"))?;
-    Ok(())
-}
 
 pub fn ensure_clean_dir(dir: &str) -> Result<()> {
     let path = Path::new(dir);
@@ -83,10 +60,16 @@ pub fn ensure_binary<T: AsRef<Path>>(path: T, contents: &[u8]) -> Result<()> {
     Ok(())
 }
 
+#[cfg(target_os = "android")]
 pub fn getprop(prop: &str) -> Option<String> {
     android_properties::getprop(prop).value()
 }
 
+#[cfg(not(target_os = "android"))]
+pub fn getprop(prop: &str) -> Option<String> {
+    unimplemented!()
+}
+
 pub fn is_safe_mode() -> bool {
     getprop("persist.sys.safemode")
         .filter(|prop| prop == "1")