Add statfs support (#3018)

* Add statfs hook

* + changelog.d

* Fix test statfs_fstatfs.rs

* Fix statfs_fstatfs.c

* Fix statfs_fstatfs.c

* Fix statfs_fstatfs.rs

* Fix statfs_fstatfs.rs

* Fix statfs_fstatfs.rs

* Update file.rs

* PR comments

changelog.d/statfs.added.md

@@ -0,0 +1 @@
+Add statfs support

mirrord/agent/src/file.rs

@@ -223,8 +223,12 @@ impl FileManager {
                 Some(FileResponse::Xstat(xstat_result))
             }
             FileRequest::XstatFs(XstatFsRequest { fd }) => {
-                let xstat_result = self.xstatfs(fd);
-                Some(FileResponse::XstatFs(xstat_result))
+                let xstatfs_result = self.xstatfs(fd);
+                Some(FileResponse::XstatFs(xstatfs_result))
+            }
+            FileRequest::StatFs(StatFsRequest { path }) => {
+                let statfs_result = self.statfs(path);
+                Some(FileResponse::XstatFs(statfs_result))
             }
 
             // dir operations
@@ -769,6 +773,18 @@ impl FileManager {
         })
     }
 
+    #[tracing::instrument(level = "trace", skip(self))]
+    pub(crate) fn statfs(&mut self, path: PathBuf) -> RemoteResult<XstatFsResponse> {
+        let path = resolve_path(path, &self.root_path)?;
+
+        let statfs = nix::sys::statfs::statfs(&path)
+            .map_err(|err| std::io::Error::from_raw_os_error(err as i32))?;
+
+        Ok(XstatFsResponse {
+            metadata: statfs.into(),
+        })
+    }
+
     #[tracing::instrument(level = Level::TRACE, skip(self), err(level = Level::DEBUG))]
     pub(crate) fn fdopen_dir(&mut self, fd: u64) -> RemoteResult<OpenDirResponse> {
         let path = match self

mirrord/intproxy/protocol/src/lib.rs

@@ -387,6 +387,13 @@ impl_request!(
     res_path = ProxyToLayerMessage::File => FileResponse::XstatFs,
 );
 
+impl_request!(
+    req = StatFsRequest,
+    res = RemoteResult<XstatFsResponse>,
+    req_path = LayerToProxyMessage::File => FileRequest::StatFs,
+    res_path = ProxyToLayerMessage::File => FileResponse::XstatFs,
+);
+
 impl_request!(
     req = FdOpenDirRequest,
     res = RemoteResult<OpenDirResponse>,

mirrord/intproxy/src/proxies/files.rs

@@ -6,7 +6,7 @@ use mirrord_protocol::{
     file::{
         CloseDirRequest, CloseFileRequest, DirEntryInternal, ReadDirBatchRequest, ReadDirResponse,
         ReadFileResponse, ReadLimitedFileRequest, SeekFromInternal, MKDIR_VERSION,
-        READDIR_BATCH_VERSION, READLINK_VERSION, RMDIR_VERSION,
+        READDIR_BATCH_VERSION, READLINK_VERSION, RMDIR_VERSION, STATFS_VERSION,
     },
     ClientMessage, DaemonMessage, ErrorKindInternal, FileRequest, FileResponse, RemoteIOError,
     ResponseError,
@@ -259,21 +259,27 @@ impl FilesProxy {
 
         match request {
             FileRequest::ReadLink(..)
-                if protocol_version.is_some_and(|version| !READLINK_VERSION.matches(version)) =>
+                if protocol_version.is_none_or(|version| !READLINK_VERSION.matches(version)) =>
             {
                 Err(FileResponse::ReadLink(Err(ResponseError::NotImplemented)))
             }
             FileRequest::MakeDir(..) | FileRequest::MakeDirAt(..)
-                if protocol_version.is_some_and(|version| !MKDIR_VERSION.matches(version)) =>
+                if protocol_version.is_none_or(|version| !MKDIR_VERSION.matches(version)) =>
             {
                 Err(FileResponse::MakeDir(Err(ResponseError::NotImplemented)))
             }
             FileRequest::RemoveDir(..) | FileRequest::Unlink(..) | FileRequest::UnlinkAt(..)
                 if protocol_version
-                    .is_some_and(|version: &Version| !RMDIR_VERSION.matches(version)) =>
+                    .is_none_or(|version: &Version| !RMDIR_VERSION.matches(version)) =>
             {
                 Err(FileResponse::RemoveDir(Err(ResponseError::NotImplemented)))
             }
+            FileRequest::StatFs(..)
+                if protocol_version
+                    .is_none_or(|version: &Version| !STATFS_VERSION.matches(version)) =>
+            {
+                Err(FileResponse::XstatFs(Err(ResponseError::NotImplemented)))
+            }
             _ => Ok(()),
         }
     }

mirrord/layer/src/file/hooks.rs

@@ -904,8 +904,9 @@ unsafe extern "C" fn fstatat_detour(
     })
 }
 
+/// Hook for `libc::fstatfs`.
 #[hook_guard_fn]
-unsafe extern "C" fn fstatfs_detour(fd: c_int, out_stat: *mut statfs) -> c_int {
+pub(crate) unsafe extern "C" fn fstatfs_detour(fd: c_int, out_stat: *mut statfs) -> c_int {
     if out_stat.is_null() {
         return HookError::BadPointer.into();
     }
@@ -919,6 +920,25 @@ unsafe extern "C" fn fstatfs_detour(fd: c_int, out_stat: *mut statfs) -> c_int {
         .unwrap_or_bypass_with(|_| FN_FSTATFS(fd, out_stat))
 }
 
+/// Hook for `libc::statfs`.
+#[hook_guard_fn]
+pub(crate) unsafe extern "C" fn statfs_detour(
+    raw_path: *const c_char,
+    out_stat: *mut statfs,
+) -> c_int {
+    if out_stat.is_null() {
+        return HookError::BadPointer.into();
+    }
+
+    crate::file::ops::statfs(raw_path.checked_into())
+        .map(|res| {
+            let res = res.metadata;
+            fill_statfs(out_stat, &res);
+            0
+        })
+        .unwrap_or_bypass_with(|_| FN_STATFS(raw_path, out_stat))
+}
+
 unsafe fn realpath_logic(
     source_path: *const c_char,
     output_path: *mut c_char,
@@ -1333,6 +1353,8 @@ pub(crate) unsafe fn enable_file_hooks(hook_manager: &mut HookManager) {
             FnFstatfs,
             FN_FSTATFS
         );
+        replace!(hook_manager, "statfs", statfs_detour, FnStatfs, FN_STATFS);
+
         replace!(
             hook_manager,
             "fdopendir",
@@ -1415,6 +1437,13 @@ pub(crate) unsafe fn enable_file_hooks(hook_manager: &mut HookManager) {
             FnFstatfs,
             FN_FSTATFS
         );
+        replace!(
+            hook_manager,
+            "statfs$INODE64",
+            statfs_detour,
+            FnStatfs,
+            FN_STATFS
+        );
         replace!(
             hook_manager,
             "fdopendir$INODE64",

mirrord/layer/src/file/ops.rs

@@ -9,7 +9,8 @@ use mirrord_protocol::{
     file::{
         MakeDirAtRequest, MakeDirRequest, OpenFileRequest, OpenFileResponse, OpenOptionsInternal,
         ReadFileResponse, ReadLinkFileRequest, ReadLinkFileResponse, RemoveDirRequest,
-        SeekFileResponse, UnlinkAtRequest, WriteFileResponse, XstatFsResponse, XstatResponse,
+        SeekFileResponse, StatFsRequest, UnlinkAtRequest, WriteFileResponse, XstatFsResponse,
+        XstatResponse,
     },
     ResponseError,
 };
@@ -736,6 +737,16 @@ pub(crate) fn xstatfs(fd: RawFd) -> Detour<XstatFsResponse> {
     Detour::Success(response)
 }
 
+#[mirrord_layer_macro::instrument(level = "trace")]
+pub(crate) fn statfs(path: Detour<PathBuf>) -> Detour<XstatFsResponse> {
+    let path = path?;
+    let lstatfs = StatFsRequest { path };
+
+    let response = common::make_proxy_request_with_response(lstatfs)??;
+
+    Detour::Success(response)
+}
+
 #[cfg(target_os = "linux")]
 #[mirrord_layer_macro::instrument(level = "trace")]
 pub(crate) fn getdents64(fd: RawFd, buffer_size: u64) -> Detour<GetDEnts64Response> {

mirrord/layer/src/go/linux_x64.rs

@@ -340,6 +340,8 @@ unsafe extern "C" fn c_abi_syscall_handler(
                 faccessat_detour(param1 as _, param2 as _, param3 as _, 0) as i64
             }
             libc::SYS_fstat => fstat_detour(param1 as _, param2 as _) as i64,
+            libc::SYS_statfs => statfs_detour(param1 as _, param2 as _) as i64,
+            libc::SYS_fstatfs => fstatfs_detour(param1 as _, param2 as _) as i64,
             libc::SYS_getdents64 => getdents64_detour(param1 as _, param2 as _, param3 as _) as i64,
             #[cfg(all(target_os = "linux", not(target_arch = "aarch64")))]
             libc::SYS_mkdir => mkdir_detour(param1 as _, param2 as _) as i64,

mirrord/layer/src/go/mod.rs

@@ -101,6 +101,8 @@ unsafe extern "C" fn c_abi_syscall6_handler(
                         .into()
                 }
                 libc::SYS_fstat => fstat_detour(param1 as _, param2 as _) as i64,
+                libc::SYS_statfs => statfs_detour(param1 as _, param2 as _) as i64,
+                libc::SYS_fstatfs => fstatfs_detour(param1 as _, param2 as _) as i64,
                 libc::SYS_fsync => fsync_detour(param1 as _) as i64,
                 libc::SYS_fdatasync => fsync_detour(param1 as _) as i64,
                 libc::SYS_openat => {

mirrord/layer/tests/apps/fileops/go/main.go

@@ -7,10 +7,21 @@ import (
 
 func main() {
 	tempFile := "/tmp/test_file.txt"
-	syscall.Open(tempFile, syscall.O_CREAT|syscall.O_WRONLY, 0644)
+	fd, _ := syscall.Open(tempFile, syscall.O_CREAT|syscall.O_WRONLY, 0644)
 	var stat syscall.Stat_t
 	err := syscall.Stat(tempFile, &stat)
 	if err != nil {
 		panic(err)
 	}
+
+	var statfs syscall.Statfs_t
+	err = syscall.Statfs(tempFile, &statfs)
+	if err != nil {
+		panic(err)
+	}
+
+	err = syscall.Fstatfs(fd, &statfs)
+	if err != nil {
+		panic(err)
+	}
 }

mirrord/layer/tests/apps/statfs_fstatfs/statfs_fstatfs.c

@@ -0,0 +1,52 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <sys/fcntl.h>
+
+#if defined(__APPLE__) && defined(__MACH__)
+#include <sys/param.h>
+#include <sys/mount.h>
+#else
+#include <sys/vfs.h>
+#endif
+
+/// Test `statfs / fstatfs`.
+///
+/// Gets information about a mounted filesystem
+///
+int main()
+{
+  char *tmp_test_path = "/statfs_fstatfs_test_path";
+  mkdir(tmp_test_path, 0777);
+
+  // statfs
+  struct statfs statfs_buf;
+  if (statfs(tmp_test_path, &statfs_buf) == -1)
+  {
+    perror("statfs failed");
+    return EXIT_FAILURE;
+  }
+
+  // fstatfs
+  int fd = open(tmp_test_path, O_RDONLY);
+
+  if (fd == -1)
+  {
+    perror("Error opening tmp_test_path");
+    return 1;
+  }
+
+  struct statfs fstatfs_buf;
+  if (fstatfs(fd, &fstatfs_buf) == -1)
+  {
+    perror("fstatfs failed");
+    close(fd);
+    return EXIT_FAILURE;
+  }
+
+  close(fd);
+  return 0;
+}

mirrord/layer/tests/common/mod.rs

@@ -17,7 +17,7 @@ use mirrord_intproxy::{agent_conn::AgentConnection, IntProxy};
 use mirrord_protocol::{
     file::{
         AccessFileRequest, AccessFileResponse, OpenFileRequest, OpenOptionsInternal,
-        ReadFileRequest, SeekFromInternal, XstatRequest, XstatResponse,
+        ReadFileRequest, SeekFromInternal, XstatFsResponse, XstatRequest, XstatResponse,
     },
     tcp::{DaemonTcp, LayerTcp, NewTcpConnection, TcpClose, TcpData},
     ClientMessage, DaemonCodec, DaemonMessage, FileRequest, FileResponse,
@@ -489,6 +489,48 @@ impl TestIntProxy {
             .unwrap();
     }
 
+    /// Makes a [`FileRequest::Statefs`] and answers it.
+    pub async fn expect_statfs(&mut self, expected_path: &str) {
+        // Expecting `statfs` call with path.
+        assert_matches!(
+            self.recv().await,
+            ClientMessage::FileRequest(FileRequest::StatFs(
+                mirrord_protocol::file::StatFsRequest { path }
+            )) if path.to_str().unwrap() == expected_path
+        );
+
+        // Answer `statfs`.
+        self.codec
+            .send(DaemonMessage::File(FileResponse::XstatFs(Ok(
+                XstatFsResponse {
+                    metadata: Default::default(),
+                },
+            ))))
+            .await
+            .unwrap();
+    }
+
+    /// Makes a [`FileRequest::Xstatefs`] and answers it.
+    pub async fn expect_fstatfs(&mut self, expected_fd: u64) {
+        // Expecting `fstatfs` call with path.
+        assert_matches!(
+            self.recv().await,
+            ClientMessage::FileRequest(FileRequest::XstatFs(
+                mirrord_protocol::file::XstatFsRequest { fd }
+            )) if expected_fd == fd
+        );
+
+        // Answer `fstatfs`.
+        self.codec
+            .send(DaemonMessage::File(FileResponse::XstatFs(Ok(
+                XstatFsResponse {
+                    metadata: Default::default(),
+                },
+            ))))
+            .await
+            .unwrap();
+    }
+
     /// Makes a [`FileRequest::RemoveDir`] and answers it.
     pub async fn expect_remove_dir(&mut self, expected_dir_name: &str) {
         // Expecting `rmdir` call with path.
@@ -784,6 +826,7 @@ pub enum Application {
     Fork,
     ReadLink,
     MakeDir,
+    StatfsFstatfs,
     RemoveDir,
     OpenFile,
     CIssue2055,
@@ -841,6 +884,7 @@ impl Application {
             Application::Fork => String::from("tests/apps/fork/out.c_test_app"),
             Application::ReadLink => String::from("tests/apps/readlink/out.c_test_app"),
             Application::MakeDir => String::from("tests/apps/mkdir/out.c_test_app"),
+            Application::StatfsFstatfs => String::from("tests/apps/statfs_fstatfs/out.c_test_app"),
             Application::RemoveDir => String::from("tests/apps/rmdir/out.c_test_app"),
             Application::Realpath => String::from("tests/apps/realpath/out.c_test_app"),
             Application::NodeHTTP | Application::NodeIssue2283 | Application::NodeIssue2807 => {
@@ -1080,6 +1124,7 @@ impl Application {
             | Application::Fork
             | Application::ReadLink
             | Application::MakeDir
+            | Application::StatfsFstatfs
             | Application::RemoveDir
             | Application::Realpath
             | Application::RustFileOps
@@ -1159,6 +1204,7 @@ impl Application {
             | Application::Fork
             | Application::ReadLink
             | Application::MakeDir
+            | Application::StatfsFstatfs
             | Application::RemoveDir
             | Application::Realpath
             | Application::Go21Issue834

mirrord/layer/tests/fileops.rs

@@ -345,6 +345,9 @@ async fn go_stat(
         ))))
         .await;
 
+    intproxy.expect_statfs("/tmp/test_file.txt").await;
+    intproxy.expect_fstatfs(fd).await;
+
     test_process.wait_assert_success().await;
     test_process.assert_no_error_in_stderr().await;
 }