cap_primitives/fs/manually/
canonicalize.rs

1//! Manual path canonicalization, one component at a time, with manual symlink
2//! resolution, in order to enforce sandboxing.
3
4use super::internal_open;
5use crate::fs::{canonicalize_options, FollowSymlinks, MaybeOwnedFile};
6use std::path::{Path, PathBuf};
7use std::{fs, io};
8
9/// Implement `canonicalize` by breaking up the path into components and
10/// resolving each component individually, and resolving symbolic links
11/// manually.
12pub(crate) fn canonicalize(start: &fs::File, path: &Path) -> io::Result<PathBuf> {
13    canonicalize_with(start, path, FollowSymlinks::Yes)
14}
15
16/// The main body of `canonicalize`, which takes an extra `follow` flag
17/// allowing the caller to disable following symlinks in the last component.
18pub(crate) fn canonicalize_with(
19    start: &fs::File,
20    path: &Path,
21    follow: FollowSymlinks,
22) -> io::Result<PathBuf> {
23    let mut symlink_count = 0;
24    let mut canonical_path = PathBuf::new();
25    let start = MaybeOwnedFile::borrowed(start);
26
27    match internal_open(
28        start,
29        path,
30        canonicalize_options().follow(follow),
31        &mut symlink_count,
32        Some(&mut canonical_path),
33    ) {
34        // If the open succeeded, we got our path.
35        Ok(_) => (),
36
37        // If it failed due to an invalid argument or filename, report it.
38        Err(err) if err.kind() == io::ErrorKind::InvalidInput => {
39            return Err(err);
40        }
41        #[cfg(io_error_more)]
42        Err(err) if err.kind() == io::ErrorKind::InvalidFilename => {
43            return Err(err);
44        }
45        #[cfg(windows)]
46        Err(err)
47            if err.raw_os_error()
48                == Some(windows_sys::Win32::Foundation::ERROR_INVALID_NAME as _)
49                || err.raw_os_error()
50                    == Some(windows_sys::Win32::Foundation::ERROR_DIRECTORY as _) =>
51        {
52            return Err(err);
53        }
54
55        // For any other error, like permission denied, it's ok as long as
56        // we got our path.
57        Err(err) => {
58            if canonical_path.as_os_str().is_empty() {
59                return Err(err);
60            }
61        }
62    }
63
64    Ok(canonical_path)
65}
cap_primitives/fs/manually/canonicalize.rs

cap_primitives/fs/manually/
canonicalize.rs
