synaps_cli/tools/
bash.rs

1use serde_json::{json, Value};
2use zeroize::Zeroize;
3use crate::{Result, RuntimeError};
4use super::{Tool, ToolContext, strip_ansi};
5
6pub struct BashTool;
7
8const READ_CHUNK_SIZE: usize = 1024;
9const MAX_STREAMED_DELTA_BYTES: usize = 16 * 1024;
10
11#[derive(Debug, Clone, Copy, PartialEq, Eq)]
12enum PromptKind {
13    Sudo,
14    Password,
15}
16
17fn sanitize_output(input: &[u8]) -> String {
18    let lossy = String::from_utf8_lossy(input);
19    let stripped = strip_ansi(&lossy);
20    stripped
21        .chars()
22        .filter(|ch| {
23            *ch == '\n'
24                || *ch == '\r'
25                || *ch == '\t'
26                || (!ch.is_control() && *ch != '\u{7f}')
27        })
28        .collect()
29}
30
31fn detect_password_prompt(text: &str) -> Option<PromptKind> {
32    let lower = text.to_ascii_lowercase();
33    let has_password = lower.contains("password");
34    if !has_password {
35        return None;
36    }
37    if lower.contains("[sudo]") || lower.contains("sudo") {
38        Some(PromptKind::Sudo)
39    } else if lower.trim_end().ends_with(':') || lower.contains("password:") {
40        Some(PromptKind::Password)
41    } else {
42        None
43    }
44}
45
46fn append_bounded(output: &mut String, text: &str, max_output: usize) -> bool {
47    if output.len() >= max_output {
48        return false;
49    }
50    let remaining = max_output - output.len();
51    if text.len() <= remaining {
52        output.push_str(text);
53        true
54    } else {
55        let mut end = remaining;
56        while end > 0 && !text.is_char_boundary(end) {
57            end -= 1;
58        }
59        output.push_str(&text[..end]);
60        false
61    }
62}
63
64pub(crate) fn bash_script_with_secure_sudo(command: &str) -> String {
65    // sudo normally opens /dev/tty for password input, bypassing our piped
66    // stdin/stderr and corrupting the TUI. In the non-interactive bash tool,
67    // shadow simple `sudo ...` invocations with a shell function that forces
68    // sudo to read from stdin and write the prompt to stderr, where the secure
69    // prompt detector can intercept it before it reaches chat/model output.
70    format!(
71        r#"sudo() {{
72    command sudo -S -p '[sudo] password required: ' "$@"
73}}
74{command}"#
75    )
76}
77
78#[async_trait::async_trait]
79impl Tool for BashTool {
80    fn name(&self) -> &str { "bash" }
81
82    fn description(&self) -> &str {
83        "Execute a bash command and return its output. Use for running programs, installing packages, git operations, and any shell commands. Commands time out after 30 seconds by default; pass a larger timeout when needed. If sudo asks for a password, the user is prompted securely in the TUI and the password is never shown to the model."
84    }
85
86    fn parameters(&self) -> Value {
87        json!({
88            "type": "object",
89            "properties": {
90                "command": {
91                    "type": "string",
92                    "description": "The bash command to execute"
93                },
94                "timeout": {
95                    "type": "integer",
96                    "description": "Timeout in seconds (default: 30). Use a larger value for long-running commands."
97                }
98            },
99            "required": ["command"]
100        })
101    }
102
103    async fn execute(&self, params: Value, ctx: ToolContext) -> Result<String> {
104        let command = params["command"].as_str()
105            .ok_or_else(|| RuntimeError::Tool("Missing command parameter".to_string()))?;
106
107        let timeout_secs = params["timeout"].as_u64().unwrap_or(ctx.limits.bash_timeout);
108        let max_output = ctx.limits.max_tool_output;
109
110        let script = bash_script_with_secure_sudo(command);
111        let mut child = tokio::process::Command::new("bash")
112            .arg("-c")
113            .arg(&script)
114            .stdin(std::process::Stdio::piped())
115            .stdout(std::process::Stdio::piped())
116            .stderr(std::process::Stdio::piped())
117            .kill_on_drop(true)
118            .spawn()
119            .map_err(|e| RuntimeError::Tool(e.to_string()))?;
120
121        let stdout = child.stdout.take()
122            .ok_or_else(|| RuntimeError::Tool("Failed to capture stdout".to_string()))?;
123        let stderr = child.stderr.take()
124            .ok_or_else(|| RuntimeError::Tool("Failed to capture stderr".to_string()))?;
125        let stdin = child.stdin.take()
126            .ok_or_else(|| RuntimeError::Tool("Failed to capture stdin".to_string()))?;
127
128        let (tx_inter, mut rx_inter) = tokio::sync::mpsc::unbounded_channel::<(bool, String)>();
129
130        let tx_o = tx_inter.clone();
131        tokio::spawn(async move {
132            use tokio::io::AsyncReadExt;
133            let mut reader = stdout;
134            let mut buf = vec![0u8; READ_CHUNK_SIZE];
135            loop {
136                match reader.read(&mut buf).await {
137                    Ok(0) => break,
138                    Ok(n) => {
139                        let msg = sanitize_output(&buf[..n]);
140                        if !msg.is_empty() {
141                            let _ = tx_o.send((false, msg));
142                        }
143                    }
144                    Err(_) => break,
145                }
146            }
147        });
148
149        let tx_e = tx_inter.clone();
150        tokio::spawn(async move {
151            use tokio::io::AsyncReadExt;
152            let mut reader = stderr;
153            let mut buf = vec![0u8; READ_CHUNK_SIZE];
154            loop {
155                match reader.read(&mut buf).await {
156                    Ok(0) => break,
157                    Ok(n) => {
158                        let msg = sanitize_output(&buf[..n]);
159                        if !msg.is_empty() {
160                            let _ = tx_e.send((true, msg));
161                        }
162                    }
163                    Err(_) => break,
164                }
165            }
166        });
167
168        drop(tx_inter);
169
170        let result = tokio::time::timeout(tokio::time::Duration::from_secs(timeout_secs), async {
171            use tokio::io::AsyncWriteExt;
172
173            let mut stdin = stdin;
174            let mut full_output = String::new();
175            let mut stderr_tail = String::new();
176            let mut truncated = false;
177            let mut streamed_bytes = 0usize;
178            let mut redactions: Vec<String> = Vec::new();
179
180            while let Some((is_stderr, mut msg)) = rx_inter.recv().await {
181                if is_stderr {
182                    stderr_tail.push_str(&msg);
183                    if stderr_tail.len() > 512 {
184                        let keep_from = stderr_tail.len() - 512;
185                        if let Some((idx, _)) = stderr_tail.char_indices().find(|(i, _)| *i >= keep_from) {
186                            stderr_tail.drain(..idx);
187                        }
188                    }
189                    if let Some(kind) = detect_password_prompt(&stderr_tail) {
190                        let prompt_text = stderr_tail.trim().to_string();
191                        let secret = match &ctx.capabilities.secret_prompt {
192                            Some(prompt) => prompt.prompt(
193                                match kind {
194                                    PromptKind::Sudo => "sudo password required".to_string(),
195                                    PromptKind::Password => "password required".to_string(),
196                                },
197                                prompt_text.clone(),
198                            ).await,
199                            None => None,
200                        };
201                        match secret {
202                            Some(mut value) => {
203                                let secret_value = value.clone();
204                                if !secret_value.is_empty() {
205                                    redactions.push(secret_value);
206                                }
207                                value.push('\n');
208                                let write_result = stdin.write_all(value.as_bytes()).await;
209                                let flush_result = stdin.flush().await;
210                                // Zeroize the password from memory immediately after use
211                                value.zeroize();
212                                write_result.map_err(|e| RuntimeError::Tool(e.to_string()))?;
213                                flush_result.map_err(|e| RuntimeError::Tool(e.to_string()))?;
214                            }
215                            None => {
216                                let _ = child.kill().await;
217                                return Err(RuntimeError::Tool("Command canceled while waiting for password".to_string()));
218                            }
219                        }
220                        let prompt_len = prompt_text.len();
221                        if prompt_len <= msg.len() {
222                            let keep_len = msg.len() - prompt_len;
223                            msg.truncate(keep_len);
224                        } else {
225                            msg.clear();
226                        }
227                        stderr_tail.clear();
228                    }
229                }
230
231                for secret in &redactions {
232                    if !secret.is_empty() {
233                        msg = msg.replace(secret, "[redacted]");
234                    }
235                }
236
237                if truncated {
238                    continue;
239                }
240
241                let added_all = append_bounded(&mut full_output, &msg, max_output);
242                if let Some(ref txd) = ctx.channels.tx_delta {
243                    if streamed_bytes < MAX_STREAMED_DELTA_BYTES {
244                        let remaining = MAX_STREAMED_DELTA_BYTES - streamed_bytes;
245                        let delta = if msg.len() <= remaining {
246                            msg.clone()
247                        } else {
248                            let mut end = remaining;
249                            while end > 0 && !msg.is_char_boundary(end) {
250                                end -= 1;
251                            }
252                            msg[..end].to_string()
253                        };
254                        streamed_bytes += delta.len();
255                        if !delta.is_empty() {
256                            let _ = txd.send(delta);
257                        }
258                    }
259                }
260
261                if !added_all {
262                    full_output.push_str(&format!("\n\n[output truncated at {}]", max_output));
263                    if let Some(ref txd) = ctx.channels.tx_delta {
264                        let _ = txd.send(format!("\n\n[output truncated at {}]", max_output));
265                    }
266                    truncated = true;
267                    let _ = child.kill().await;
268                }
269            }
270            let status = child.wait().await.map_err(|e| RuntimeError::Tool(e.to_string()))?;
271            // Zeroize redactions (passwords) from memory now that command is done
272            for secret in &mut redactions {
273                secret.zeroize();
274            }
275            Ok::<_, RuntimeError>((status, full_output, truncated))
276        }).await;
277
278        match result {
279            Ok(Ok((status, output, was_truncated))) => {
280                if status.success() || was_truncated {
281                    Ok(output)
282                } else {
283                    Err(RuntimeError::Tool(format!(
284                        "Command failed (exit {}):\n{}",
285                        status.code().unwrap_or(-1), output
286                    )))
287                }
288            }
289            Ok(Err(e)) => Err(RuntimeError::Tool(format!("Failed to execute command: {}", e))),
290            Err(_) => Err(RuntimeError::Tool(format!("Command timed out after {}s", timeout_secs))),
291        }
292    }
293}
294
295#[cfg(test)]
296mod tests {
297    use super::*;
298
299    #[test]
300    fn detects_sudo_password_prompt_without_newline() {
301        assert_eq!(detect_password_prompt("[sudo] password for me: "), Some(PromptKind::Sudo));
302    }
303
304    #[test]
305    fn sanitizes_terminal_control_sequences_and_nuls() {
306        let cleaned = sanitize_output(b"ok\x1b[2J\x00done");
307        assert_eq!(cleaned, "okdone");
308    }
309
310    use super::super::test_helpers::create_tool_context;
311    use crate::tools::Tool;
312    use serde_json::json;
313
314    #[test]
315    fn test_bash_tool_schema() {
316        let tool = BashTool;
317        assert_eq!(tool.name(), "bash");
318        assert!(!tool.description().is_empty());
319
320        let params = tool.parameters();
321        assert_eq!(params["type"], "object");
322        assert!(params["properties"].is_object());
323        assert!(params["required"].is_array());
324    }
325
326    #[tokio::test]
327    async fn test_bash_tool_execution() {
328        let tool = BashTool;
329
330        // Test simple echo command
331        let ctx = create_tool_context();
332        let params = json!({
333            "command": "echo hello"
334        });
335
336        let result = tool.execute(params, ctx).await.unwrap();
337        assert!(result.contains("hello"));
338
339        // Test timeout parameter with quick command
340        let ctx = create_tool_context();
341        let params = json!({
342            "command": "sleep 1",
343            "timeout": 2
344        });
345
346        let result = tool.execute(params, ctx).await;
347        // Should succeed (1 second sleep with 2 second timeout)
348        assert!(result.is_ok());
349
350        // Test timeout with longer command
351        let ctx = create_tool_context();
352        let params = json!({
353            "command": "sleep 3",
354            "timeout": 1
355        });
356
357        let result = tool.execute(params, ctx).await;
358        // Should timeout
359        assert!(result.is_err());
360        assert!(result.unwrap_err().to_string().contains("timed out"));
361    }
362
363    #[tokio::test]
364    async fn test_bash_tool_requested_timeout_is_not_clamped_by_max_timeout() {
365        let tool = BashTool;
366        let mut ctx = create_tool_context();
367        ctx.limits.bash_max_timeout = 1;
368
369        let params = json!({
370            "command": "sleep 2; echo done",
371            "timeout": 3
372        });
373
374        let result = tool.execute(params, ctx).await;
375        assert!(result.is_ok(), "requested timeout should not be clamped by bash_max_timeout: {result:?}");
376        assert!(result.unwrap().contains("done"));
377    }
378
379    #[tokio::test]
380    async fn test_bash_fake_sudo_prompt_uses_secret_prompt_and_redacts_password() {
381        let tool = BashTool;
382        let (prompt_tx, mut prompt_rx) = tokio::sync::mpsc::unbounded_channel();
383        let prompt_handle = crate::tools::SecretPromptHandle::new(prompt_tx);
384        let (delta_tx, mut delta_rx) = tokio::sync::mpsc::unbounded_channel();
385
386        let responder = tokio::spawn(async move {
387            let req = prompt_rx.recv().await.expect("bash should request a secret prompt");
388            assert!(req.prompt.to_ascii_lowercase().contains("password"), "prompt was {:?}", req.prompt);
389            req.response_tx.send(Some("swordfish".to_string())).unwrap();
390        });
391
392        let mut ctx = create_tool_context();
393        ctx.capabilities.secret_prompt = Some(prompt_handle);
394        ctx.channels.tx_delta = Some(delta_tx);
395        let params = json!({
396            "command": "printf '[sudo] password for testuser: ' >&2; read -r pw; if [ \"$pw\" = swordfish ]; then echo AUTH_OK; else echo AUTH_FAIL; fi",
397            "timeout": 5
398        });
399
400        let result = tool.execute(params, ctx).await.unwrap();
401        responder.await.unwrap();
402        let mut streamed = String::new();
403        while let Ok(delta) = delta_rx.try_recv() {
404            streamed.push_str(&delta);
405        }
406
407        assert!(result.contains("AUTH_OK"));
408        assert!(!result.contains("swordfish"));
409        assert!(!result.contains("[sudo] password"));
410        assert!(!streamed.contains("[sudo] password"));
411    }
412
413    #[test]
414    fn test_bash_wraps_sudo_to_force_stdin_prompt() {
415        let script = super::bash_script_with_secure_sudo("sudo id");
416
417        assert!(script.contains("sudo()"));
418        assert!(script.contains("command sudo -S -p '[sudo] password required: '"));
419        assert!(script.ends_with("sudo id"));
420    }
421
422    #[tokio::test]
423    async fn test_bash_sudo_function_prompt_is_intercepted_before_streaming() {
424        let tool = BashTool;
425        let (prompt_tx, mut prompt_rx) = tokio::sync::mpsc::unbounded_channel();
426        let prompt_handle = crate::tools::SecretPromptHandle::new(prompt_tx);
427        let (delta_tx, mut delta_rx) = tokio::sync::mpsc::unbounded_channel();
428
429        let responder = tokio::spawn(async move {
430            let req = prompt_rx.recv().await.expect("bash should request a secret prompt");
431            assert!(req.prompt.contains("[sudo] password required"), "prompt was {:?}", req.prompt);
432            req.response_tx.send(Some("wrong-password-for-test".to_string())).unwrap();
433        });
434
435        let mut ctx = create_tool_context();
436        ctx.capabilities.secret_prompt = Some(prompt_handle);
437        ctx.channels.tx_delta = Some(delta_tx);
438        let params = json!({
439            "command": "sudo -k; sudo -v",
440            "timeout": 5
441        });
442
443        let _ = tool.execute(params, ctx).await;
444        responder.await.unwrap();
445        let mut streamed = String::new();
446        while let Ok(delta) = delta_rx.try_recv() {
447            streamed.push_str(&delta);
448        }
449
450        assert!(!streamed.contains("[sudo] password required"), "sudo password prompt leaked into deltas: {streamed:?}");
451    }
452
453    #[tokio::test]
454    async fn test_bash_control_char_output_is_sanitized_and_bounded_in_deltas() {
455        let tool = BashTool;
456        let (delta_tx, mut delta_rx) = tokio::sync::mpsc::unbounded_channel();
457        let mut ctx = create_tool_context();
458        ctx.channels.tx_delta = Some(delta_tx);
459        ctx.limits.max_tool_output = 256;
460
461        let params = json!({
462            "command": "python3 -c \"import sys; sys.stdout.buffer.write(b'clean\\x1b[2J\\x00' + b'A' * 2000); sys.stdout.flush()\"",
463            "timeout": 5
464        });
465
466        let result = tool.execute(params, ctx).await.unwrap();
467        let mut streamed = String::new();
468        while let Ok(delta) = delta_rx.try_recv() {
469            streamed.push_str(&delta);
470        }
471
472        assert!(result.contains("[output truncated at 256]"));
473        assert!(!result.contains('\u{1b}'));
474        assert!(!result.contains('\0'));
475        assert!(!streamed.contains('\u{1b}'));
476        assert!(!streamed.contains('\0'));
477        assert!(streamed.len() <= 2048, "streamed deltas must be bounded, got {} bytes", streamed.len());
478    }
479
480    #[tokio::test]
481    async fn test_bash_echoed_secret_is_redacted_from_output() {
482        let tool = BashTool;
483        let (prompt_tx, mut prompt_rx) = tokio::sync::mpsc::unbounded_channel();
484        let prompt_handle = crate::tools::SecretPromptHandle::new(prompt_tx);
485
486        let responder = tokio::spawn(async move {
487            let req = prompt_rx.recv().await.expect("bash should request a secret prompt");
488            req.response_tx.send(Some("swordfish".to_string())).unwrap();
489        });
490
491        let mut ctx = create_tool_context();
492        ctx.capabilities.secret_prompt = Some(prompt_handle);
493        let params = json!({
494            "command": "printf 'Password: ' >&2; read -r pw; echo seen:$pw",
495            "timeout": 5
496        });
497
498        let result = tool.execute(params, ctx).await.unwrap();
499        responder.await.unwrap();
500
501        assert!(result.contains("seen:[redacted]"));
502        assert!(!result.contains("swordfish"));
503    }
504
505    #[tokio::test]
506    async fn test_bash_sequential_password_prompts_are_each_handled() {
507        let tool = BashTool;
508        let (prompt_tx, mut prompt_rx) = tokio::sync::mpsc::unbounded_channel();
509        let prompt_handle = crate::tools::SecretPromptHandle::new(prompt_tx);
510
511        let responder = tokio::spawn(async move {
512            for value in ["first", "second"] {
513                let req = prompt_rx.recv().await.expect("bash should request each secret prompt");
514                assert!(req.prompt.to_ascii_lowercase().contains("password"));
515                req.response_tx.send(Some(value.to_string())).unwrap();
516            }
517        });
518
519        let mut ctx = create_tool_context();
520        ctx.capabilities.secret_prompt = Some(prompt_handle);
521        let params = json!({
522            "command": "printf 'Password: ' >&2; read -r one; printf 'Password: ' >&2; read -r two; echo done:$one:$two",
523            "timeout": 5
524        });
525
526        let result = tool.execute(params, ctx).await.unwrap();
527        responder.await.unwrap();
528
529        assert!(result.contains("done:[redacted]:[redacted]"));
530        assert!(!result.contains("first"));
531        assert!(!result.contains("second"));
532    }
533
534    #[tokio::test]
535    async fn test_bash_password_prompt_cancel_kills_command_without_leaking_partial_secret() {
536        let tool = BashTool;
537        let (prompt_tx, mut prompt_rx) = tokio::sync::mpsc::unbounded_channel();
538        let prompt_handle = crate::tools::SecretPromptHandle::new(prompt_tx);
539
540        let responder = tokio::spawn(async move {
541            let req = prompt_rx.recv().await.expect("bash should request a secret prompt");
542            req.response_tx.send(None).unwrap();
543        });
544
545        let mut ctx = create_tool_context();
546        ctx.capabilities.secret_prompt = Some(prompt_handle);
547        let params = json!({
548            "command": "printf 'Password: ' >&2; read -r pw; echo should-not-run:$pw",
549            "timeout": 5
550        });
551
552        let err = tool.execute(params, ctx).await.unwrap_err().to_string();
553        responder.await.unwrap();
554
555        assert!(err.contains("waiting for password"));
556        assert!(!err.contains("should-not-run"));
557    }
558
559    #[tokio::test]
560    async fn test_bash_binary_output_is_sanitized() {
561        let tool = BashTool;
562        let ctx = create_tool_context();
563        let params = json!({
564            "command": "python3 -c \"import sys; sys.stdout.buffer.write(bytes(range(32)) + b'visible')\"",
565            "timeout": 5
566        });
567
568        let result = tool.execute(params, ctx).await.unwrap();
569
570        assert!(result.contains("visible"));
571        assert!(!result.contains('\0'));
572        assert!(!result.contains('\u{1b}'));
573    }
574
575    #[tokio::test]
576    async fn test_bash_tool_timeout() {
577        let tool = BashTool;
578        let ctx = create_tool_context();
579
580        let params = json!({
581            "command": "sleep 10",
582            "timeout": 1
583        });
584
585        let result = tool.execute(params, ctx).await;
586
587        // Should timeout and return error
588        assert!(result.is_err());
589        let error = result.unwrap_err().to_string();
590        assert!(error.contains("timed out"));
591    }
592
593    #[tokio::test]
594    async fn test_bash_tool_failure() {
595        let tool = BashTool;
596        let ctx = create_tool_context();
597
598        let params = json!({
599            "command": "exit 1"
600        });
601
602        let result = tool.execute(params, ctx).await;
603
604        // Should fail and return error
605        assert!(result.is_err());
606        let error = result.unwrap_err().to_string();
607        assert!(error.contains("failed") || error.contains("exit"));
608    }
609}
synaps_cli/tools/bash.rs

synaps_cli/tools/
bash.rs
