cp: handle special files (#11163)

Cargo.lock

@@ -3293,6 +3293,7 @@ dependencies = [
  "fluent",
  "indicatif",
  "libc",
+ "nix",
  "selinux",
  "tempfile",
  "thiserror 2.0.18",

src/uu/cp/Cargo.toml

@@ -41,6 +41,7 @@ fluent = { workspace = true }
 
 [target.'cfg(unix)'.dependencies]
 exacl = { workspace = true, optional = true }
+nix = { workspace = true, features = ["fs"] }
 
 [[bin]]
 name = "cp"

src/uu/cp/locales/en-US.ftl

@@ -87,6 +87,7 @@ cp-error-selinux-get-context = failed to get security context of { $path }
 cp-error-selinux-error = SELinux error: { $error }
 cp-error-selinux-context-conflict = cannot combine --context (-Z) with --preserve=context
 cp-error-cannot-create-fifo = cannot create fifo { $path }: File exists
+cp-error-cannot-create-special-file = cannot create special file { $path }: { $error }
 cp-error-invalid-attribute = invalid attribute { $value }
 cp-error-failed-to-create-whole-tree = failed to create whole tree
 cp-error-failed-to-create-directory = Failed to create directory: { $error }

src/uu/cp/locales/fr-FR.ftl

@@ -87,6 +87,7 @@ cp-error-selinux-get-context = échec de l'obtention du contexte de sécurité d
 cp-error-selinux-error = Erreur SELinux : { $error }
 cp-error-selinux-context-conflict = impossible de combiner --context (-Z) avec --preserve=context
 cp-error-cannot-create-fifo = impossible de créer le fifo { $path } : Le fichier existe
+cp-error-cannot-create-special-file = impossible de créer le fichier spécial { $path } : { $error }
 cp-error-invalid-attribute = attribut invalide { $value }
 cp-error-failed-to-create-whole-tree = échec de la création de l'arborescence complète
 cp-error-failed-to-create-directory = Échec de la création du répertoire : { $error }

src/uu/cp/src/cp.rs

@@ -2,7 +2,7 @@
 //
 // For the full copyright and license information, please view the LICENSE
 // file that was distributed with this source code.
-// spell-checker:ignore (ToDO) copydir ficlone fiemap ftruncate linkgs lstat nlink nlinks pathbuf pwrite reflink strs xattrs symlinked deduplicated advcpmv nushell IRWXG IRWXO IRWXU IRWXUGO IRWXU IRWXG IRWXO IRWXUGO
+// spell-checker:ignore (ToDO) copydir ficlone fiemap ftruncate linkgs lstat nlink nlinks pathbuf pwrite reflink strs xattrs symlinked deduplicated advcpmv nushell IRWXG IRWXO IRWXU IRWXUGO IRWXU IRWXG IRWXO IRWXUGO sflag
 
 use std::cmp::Ordering;
 use std::collections::{HashMap, HashSet};
@@ -10,7 +10,7 @@ use std::ffi::OsString;
 use std::fmt::Display;
 use std::fs::{self, Metadata, OpenOptions, Permissions};
 #[cfg(unix)]
-use std::os::unix::fs::{FileTypeExt, PermissionsExt};
+use std::os::unix::fs::{FileTypeExt, MetadataExt, PermissionsExt};
 #[cfg(unix)]
 use std::os::unix::net::UnixListener;
 use std::path::{Path, PathBuf, StripPrefixError};
@@ -22,6 +22,8 @@ use uucore::translate;
 use clap::{Arg, ArgAction, ArgMatches, Command, builder::ValueParser, value_parser};
 use filetime::FileTime;
 use indicatif::{ProgressBar, ProgressStyle};
+#[cfg(unix)]
+use nix::sys::stat::{Mode, SFlag, dev_t, mknod as nix_mknod, mode_t};
 use thiserror::Error;
 
 use platform::copy_on_write;
@@ -2227,13 +2229,8 @@ fn handle_copy_mode(
     source_metadata: &Metadata,
     symlinked_files: &mut HashSet<FileInformation>,
     source_in_command_line: bool,
-    source_is_fifo: bool,
-    source_is_socket: bool,
     created_parent_dirs: &mut HashSet<PathBuf>,
-    #[cfg(unix)] source_is_stream: bool,
 ) -> CopyResult<PerformedAction> {
-    let source_is_symlink = source_metadata.is_symlink();
-
     match options.copy_mode {
         CopyMode::Link => {
             if dest.exists() {
@@ -2267,13 +2264,9 @@ fn handle_copy_mode(
                 dest,
                 options,
                 context,
-                source_is_symlink,
-                source_is_fifo,
-                source_is_socket,
+                source_metadata,
                 symlinked_files,
                 created_parent_dirs,
-                #[cfg(unix)]
-                source_is_stream,
             )?;
         }
         CopyMode::SymLink => {
@@ -2291,13 +2284,9 @@ fn handle_copy_mode(
                             dest,
                             options,
                             context,
-                            source_is_symlink,
-                            source_is_fifo,
-                            source_is_socket,
+                            source_metadata,
                             symlinked_files,
                             created_parent_dirs,
-                            #[cfg(unix)]
-                            source_is_stream,
                         )?;
                     }
                     UpdateMode::None => {
@@ -2328,13 +2317,9 @@ fn handle_copy_mode(
                             dest,
                             options,
                             context,
-                            source_is_symlink,
-                            source_is_fifo,
-                            source_is_socket,
+                            source_metadata,
                             symlinked_files,
                             created_parent_dirs,
-                            #[cfg(unix)]
-                            source_is_stream,
                         )?;
                     }
                 }
@@ -2344,13 +2329,9 @@ fn handle_copy_mode(
                     dest,
                     options,
                     context,
-                    source_is_symlink,
-                    source_is_fifo,
-                    source_is_socket,
+                    source_metadata,
                     symlinked_files,
                     created_parent_dirs,
-                    #[cfg(unix)]
-                    source_is_stream,
                 )?;
             }
         }
@@ -2582,15 +2563,6 @@ fn copy_file(
         context,
     );
 
-    #[cfg(unix)]
-    let source_is_fifo = source_metadata.file_type().is_fifo();
-    #[cfg(unix)]
-    let source_is_socket = source_metadata.file_type().is_socket();
-    #[cfg(not(unix))]
-    let source_is_fifo = false;
-    #[cfg(not(unix))]
-    let source_is_socket = false;
-
     let source_is_stream = is_stream(&source_metadata);
 
     let performed_action = handle_copy_mode(
@@ -2601,11 +2573,7 @@ fn copy_file(
         &source_metadata,
         symlinked_files,
         source_in_command_line,
-        source_is_fifo,
-        source_is_socket,
         created_parent_dirs,
-        #[cfg(unix)]
-        source_is_stream,
     )?;
 
     if options.verbose && performed_action != PerformedAction::Skipped {
@@ -2741,18 +2709,14 @@ fn handle_no_preserve_mode(options: &Options, org_mode: u32) -> u32 {
 
 /// Copy the file from `source` to `dest` either using the normal `fs::copy` or a
 /// copy-on-write scheme if --reflink is specified and the filesystem supports it.
-#[allow(clippy::too_many_arguments)]
 fn copy_helper(
     source: &Path,
     dest: &Path,
     options: &Options,
     context: &str,
-    source_is_symlink: bool,
-    source_is_fifo: bool,
-    source_is_socket: bool,
+    source_metadata: &Metadata,
     symlinked_files: &mut HashSet<FileInformation>,
     created_parent_dirs: &mut HashSet<PathBuf>,
-    #[cfg(unix)] source_is_stream: bool,
 ) -> CopyResult<()> {
     if options.parents {
         let parent = dest.parent().unwrap_or(dest);
@@ -2765,13 +2729,21 @@ fn copy_helper(
         return Err(CpError::NotADirectory(dest.to_path_buf()));
     }
 
-    if source_is_socket && options.recursive && !options.copy_contents {
-        #[cfg(unix)]
-        copy_socket(dest, options.overwrite, options.debug)?;
-    } else if source_is_fifo && options.recursive && !options.copy_contents {
-        #[cfg(unix)]
-        copy_fifo(dest, options.overwrite, options.debug)?;
-    } else if source_is_symlink {
+    #[cfg(unix)]
+    if options.recursive && !options.copy_contents {
+        let ft = source_metadata.file_type();
+        if ft.is_socket() {
+            return copy_socket(dest, options.overwrite, options.debug);
+        }
+        if ft.is_fifo() {
+            return copy_fifo(dest, options.overwrite, options.debug);
+        }
+        if ft.is_char_device() || ft.is_block_device() {
+            return copy_node(dest, source_metadata, options.overwrite, options.debug);
+        }
+    }
+
+    if source_metadata.is_symlink() {
         copy_link(source, dest, symlinked_files, options)?;
     } else {
         let copy_debug = copy_on_write(
@@ -2781,7 +2753,7 @@ fn copy_helper(
             options.sparse_mode,
             context,
             #[cfg(unix)]
-            source_is_stream,
+            is_stream(source_metadata),
         )?;
 
         if !options.attributes_only && options.debug {
@@ -2816,6 +2788,27 @@ fn copy_socket(dest: &Path, overwrite: OverwriteMode, debug: bool) -> CopyResult
     Ok(())
 }
 
+#[cfg(unix)]
+fn copy_node(
+    dest: &Path,
+    source_metadata: &Metadata,
+    overwrite: OverwriteMode,
+    debug: bool,
+) -> CopyResult<()> {
+    if dest.exists() {
+        overwrite.verify(dest, debug)?;
+        fs::remove_file(dest)?;
+    }
+    let sflag = if source_metadata.file_type().is_char_device() {
+        SFlag::S_IFCHR
+    } else {
+        SFlag::S_IFBLK
+    };
+    let mode = Mode::from_bits_truncate(source_metadata.mode() as mode_t);
+    nix_mknod(dest, sflag, mode, source_metadata.rdev() as dev_t)
+        .map_err(|e| translate!("cp-error-cannot-create-special-file", "path" => dest.quote(), "error" => e.desc()).into())
+}
+
 fn copy_link(
     source: &Path,
     dest: &Path,

tests/by-util/test_cp.rs

@@ -5,6 +5,8 @@
 
 // spell-checker:ignore (flags) reflink (fs) tmpfs (linux) rlimit Rlim NOFILE clob btrfs neve ROOTDIR USERDIR outfile uufs xattrs
 // spell-checker:ignore bdfl hlsl IRWXO IRWXG nconfined matchpathcon libselinux-devel prwx doesnotexist reftests subdirs mksocket srwx
+#[cfg(unix)]
+use rstest::rstest;
 use uucore::display::Quotable;
 #[cfg(feature = "feat_selinux")]
 use uucore::selinux::get_getfattr_output;
@@ -3171,6 +3173,133 @@ fn test_cp_fifo() {
     assert_eq!(permission, "prwx-wx--x".to_string());
 }
 
+#[rstest]
+#[case::recursive("-R")]
+#[case::archive("-a")]
+#[cfg(unix)]
+fn test_cp_recursive_char_device(#[case] flag: &str) {
+    use nix::sys::stat::{Mode, SFlag, mknod as nix_mknod};
+    use std::os::unix::fs::{FileTypeExt, MetadataExt, PermissionsExt};
+    use uutests::util::run_ucmd_as_root;
+    let ts = TestScenario::new(util_name!());
+    let at = &ts.fixtures;
+    let mode = Mode::S_IRUSR | Mode::S_IWUSR | Mode::S_IRGRP;
+    if nix_mknod(
+        at.plus("null").as_path(),
+        SFlag::S_IFCHR,
+        mode,
+        uucore::fs::makedev(1, 3),
+    )
+    .is_err()
+    {
+        print!("Test skipped; creating a char device node requires CAP_MKNOD");
+        return;
+    }
+    if let Ok(result) = run_ucmd_as_root(&ts, &[flag, "null", "null2"]) {
+        result.success();
+        let null2_metadata = at.plus("null2").metadata().unwrap();
+        assert!(null2_metadata.file_type().is_char_device());
+        assert_eq!(
+            null2_metadata.rdev(),
+            at.plus("null").metadata().unwrap().rdev()
+        );
+        assert_eq!(
+            null2_metadata.permissions().mode() & 0o777,
+            mode.bits() as _
+        );
+    } else {
+        print!("Test skipped; copying a char device node requires CAP_MKNOD");
+    }
+}
+
+#[rstest]
+#[case::recursive("-R")]
+#[case::archive("-a")]
+#[cfg(unix)]
+fn test_cp_recursive_char_device_no_permission(#[case] flag: &str) {
+    new_ucmd!()
+        .args(&[flag, "/dev/null", "null2"])
+        .fails()
+        .stderr_is("cp: cannot create special file 'null2': Operation not permitted\n");
+}
+
+#[test]
+#[cfg(unix)]
+fn test_cp_recursive_char_device_copy_contents() {
+    let (at, mut ucmd) = at_and_ucmd!();
+    ucmd.args(&["-R", "--copy-contents", "/dev/null", "null2"])
+        .succeeds()
+        .no_stderr();
+    assert!(at.plus("null2").metadata().unwrap().file_type().is_file());
+    assert_eq!(at.read("null2"), "");
+}
+
+#[test]
+#[cfg(unix)]
+fn test_cp_char_device() {
+    let (at, mut ucmd) = at_and_ucmd!();
+    ucmd.args(&["/dev/null", "null2"]).succeeds().no_stderr();
+    assert!(at.plus("null2").metadata().unwrap().file_type().is_file());
+    assert_eq!(at.read("null2"), "");
+}
+
+#[rstest]
+#[case::recursive("-R")]
+#[case::archive("-a")]
+#[cfg(unix)]
+fn test_cp_recursive_block_device(#[case] flag: &str) {
+    use nix::sys::stat::{Mode, SFlag, mknod as nix_mknod};
+    use std::os::unix::fs::{FileTypeExt, MetadataExt};
+    use uutests::util::run_ucmd_as_root;
+    let ts = TestScenario::new(util_name!());
+    let at = &ts.fixtures;
+    if nix_mknod(
+        at.plus("sda").as_path(),
+        SFlag::S_IFBLK,
+        Mode::S_IRUSR | Mode::S_IWUSR,
+        uucore::fs::makedev(8, 0),
+    )
+    .is_err()
+    {
+        print!("Test skipped; creating a block device node requires CAP_MKNOD");
+        return;
+    }
+    if let Ok(result) = run_ucmd_as_root(&ts, &[flag, "sda", "sda2"]) {
+        result.success();
+        let sda2_metadata = at.plus("sda2").metadata().unwrap();
+        assert!(sda2_metadata.file_type().is_block_device());
+        assert_eq!(
+            sda2_metadata.rdev(),
+            at.plus("sda").metadata().unwrap().rdev()
+        );
+    } else {
+        print!("Test skipped; copying a block device node requires CAP_MKNOD");
+    }
+}
+
+#[test]
+#[cfg(unix)]
+fn test_cp_block_device_no_permission() {
+    use nix::sys::stat::{Mode, SFlag, mknod as nix_mknod};
+    let ts = TestScenario::new(util_name!());
+    let at = &ts.fixtures;
+    if nix_mknod(
+        at.plus("sda").as_path(),
+        SFlag::S_IFBLK,
+        Mode::S_IRUSR | Mode::S_IWUSR,
+        uucore::fs::makedev(8, 0),
+    )
+    .is_err()
+    {
+        print!("Test skipped; creating a block device node requires CAP_MKNOD");
+        return;
+    }
+    ts.ucmd()
+        .args(&["-R", "sda", "sda2"])
+        .fails()
+        .stderr_is("cp: cannot create special file 'sda2': Operation not permitted\n");
+}
+
 #[test]
 #[cfg(unix)]
 fn test_cp_socket() {