lean_ctx/core/
pathjail.rs

1use std::path::{Path, PathBuf};
2
3const IDE_CONFIG_DIRS: &[&str] = &[
4    ".lean-ctx",
5    ".cursor",
6    ".claude",
7    ".codex",
8    ".codeium",
9    ".gemini",
10    ".qwen",
11    ".trae",
12    ".kiro",
13    ".verdent",
14    ".pi",
15    ".amp",
16    ".aider",
17    ".continue",
18];
19
20fn allow_paths_from_env() -> Vec<PathBuf> {
21    let mut out = Vec::new();
22
23    if let Ok(data_dir) = crate::core::data_dir::lean_ctx_data_dir() {
24        out.push(canonicalize_or_self(&data_dir));
25    }
26
27    if let Some(home) = dirs::home_dir() {
28        for dir in IDE_CONFIG_DIRS {
29            let p = home.join(dir);
30            if p.exists() {
31                out.push(canonicalize_or_self(&p));
32            }
33        }
34    }
35
36    let v = std::env::var("LCTX_ALLOW_PATH")
37        .or_else(|_| std::env::var("LEAN_CTX_ALLOW_PATH"))
38        .unwrap_or_default();
39    if v.trim().is_empty() {
40        return out;
41    }
42    for p in std::env::split_paths(&v) {
43        if let Ok(canon) = std::fs::canonicalize(&p) {
44            out.push(canon);
45        } else {
46            out.push(p);
47        }
48    }
49    out
50}
51
52fn is_under_prefix(path: &Path, prefix: &Path) -> bool {
53    path.starts_with(prefix)
54}
55
56fn canonicalize_or_self(path: &Path) -> PathBuf {
57    std::fs::canonicalize(path).unwrap_or_else(|_| path.to_path_buf())
58}
59
60fn canonicalize_existing_ancestor(path: &Path) -> Option<(PathBuf, Vec<std::ffi::OsString>)> {
61    let mut cur = path.to_path_buf();
62    let mut remainder: Vec<std::ffi::OsString> = Vec::new();
63    loop {
64        if cur.exists() {
65            return Some((canonicalize_or_self(&cur), remainder));
66        }
67        let name = cur.file_name()?.to_os_string();
68        remainder.push(name);
69        if !cur.pop() {
70            return None;
71        }
72    }
73}
74
75pub fn jail_path(candidate: &Path, jail_root: &Path) -> Result<PathBuf, String> {
76    let root = canonicalize_or_self(jail_root);
77    let allow = allow_paths_from_env();
78
79    let (base, remainder) = canonicalize_existing_ancestor(candidate).ok_or_else(|| {
80        format!(
81            "path does not exist and has no existing ancestor: {}",
82            candidate.display()
83        )
84    })?;
85
86    let allowed = is_under_prefix(&base, &root) || allow.iter().any(|p| is_under_prefix(&base, p));
87
88    #[cfg(windows)]
89    let allowed = allowed || is_under_prefix_windows(&base, &root);
90
91    if !allowed {
92        return Err(format!(
93            "path escapes project root: {} (root: {})",
94            candidate.display(),
95            root.display()
96        ));
97    }
98
99    #[cfg(windows)]
100    reject_symlink_on_windows(candidate)?;
101
102    let mut out = base;
103    for part in remainder.iter().rev() {
104        out.push(part);
105    }
106    Ok(out)
107}
108
109#[cfg(windows)]
110fn is_under_prefix_windows(path: &Path, prefix: &Path) -> bool {
111    let path_str = path.to_string_lossy().to_lowercase().replace('/', "\\");
112    let prefix_str = prefix.to_string_lossy().to_lowercase().replace('/', "\\");
113    path_str.starts_with(&prefix_str)
114}
115
116#[cfg(windows)]
117fn reject_symlink_on_windows(path: &Path) -> Result<(), String> {
118    if let Ok(meta) = std::fs::symlink_metadata(path) {
119        if meta.is_symlink() {
120            return Err(format!(
121                "symlink not allowed in jailed path: {}",
122                path.display()
123            ));
124        }
125    }
126    Ok(())
127}
128
129#[cfg(test)]
130mod tests {
131    use super::*;
132
133    #[test]
134    fn rejects_path_outside_root() {
135        let tmp = tempfile::tempdir().unwrap();
136        let root = tmp.path().join("root");
137        let other = tmp.path().join("other");
138        std::fs::create_dir_all(&root).unwrap();
139        std::fs::create_dir_all(&other).unwrap();
140        std::fs::write(root.join("a.txt"), "ok").unwrap();
141        std::fs::write(other.join("b.txt"), "no").unwrap();
142
143        let ok = jail_path(&root.join("a.txt"), &root);
144        assert!(ok.is_ok());
145
146        let bad = jail_path(&other.join("b.txt"), &root);
147        assert!(bad.is_err());
148    }
149
150    #[test]
151    fn allows_nonexistent_child_under_root() {
152        let tmp = tempfile::tempdir().unwrap();
153        let root = tmp.path().join("root");
154        std::fs::create_dir_all(&root).unwrap();
155        std::fs::write(root.join("a.txt"), "ok").unwrap();
156
157        let p = root.join("new").join("file.txt");
158        let ok = jail_path(&p, &root).unwrap();
159        assert!(ok.to_string_lossy().contains("file.txt"));
160    }
161
162    #[test]
163    fn ide_config_dirs_list_is_not_empty() {
164        assert!(IDE_CONFIG_DIRS.len() >= 10);
165        assert!(IDE_CONFIG_DIRS.contains(&".codex"));
166        assert!(IDE_CONFIG_DIRS.contains(&".cursor"));
167        assert!(IDE_CONFIG_DIRS.contains(&".claude"));
168        assert!(IDE_CONFIG_DIRS.contains(&".gemini"));
169    }
170}
lean_ctx/core/pathjail.rs

lean_ctx/core/
pathjail.rs
