protolens 0.2.3

TCP stream reassembly,application layer protocol parsing
Documentation
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
use crate::{
    CbSmbFile, CbSmbFileStart, CbSmbFileStop, DirConfirmFn, Parser, ParserFactory, ParserFuture,
    PktStrm, Prolens, SMB_PORT, SharedStateManager, packet::*,
};
use byteorder::{BigEndian, ByteOrder, LittleEndian};
use std::ffi::c_void;
use std::marker::PhantomData;

pub struct SmbParser<T>
where
    T: Packet,
{
    version: ValidVer,
    encrypt: EncryptMng,
    cb_file_start: Option<CbSmbFileStart>,
    cb_file: Option<CbSmbFile>,
    cb_file_stop: Option<CbSmbFileStop>,
    _phantom_t: PhantomData<T>,
}

impl<T> SmbParser<T>
where
    T: Packet,
{
    pub(crate) fn new() -> Self {
        Self {
            version: ValidVer::new(),
            encrypt: EncryptMng::new(),
            cb_file_start: None,
            cb_file: None,
            cb_file_stop: None,
            _phantom_t: PhantomData,
        }
    }

    async fn c2s_parser_inner(
        strm: *mut PktStrm<T>,
        cb_smb: SmbCallbacks,
        cb_ctx: *mut c_void,
        valid_ver: ValidVer,
        encrypt: EncryptMng,
    ) -> Result<(), ()> {
        let stm = unsafe { &mut *strm };

        if !valid_ver.wait_for().await {
            return Err(());
        }

        if encrypt.wait_for().await {
            return Err(());
        }

        loop {
            let (byte, _seq) = stm.readn(4).await?;
            let netbios_len = BigEndian::read_u24(&byte[1..4]) as usize;
            let start_size = stm.get_read_size();
            loop {
                let header = Self::header(stm).await?;
                match header.command {
                    command::READ => Self::read_req(stm, header, &cb_smb, cb_ctx).await?,
                    command::WRITE => Self::write_req(stm, header, &cb_smb, cb_ctx).await?,
                    _ => Self::consume(stm, netbios_len - HEADER_SIZE as usize).await?,
                }

                let cmd_size = stm.get_read_size().saturating_sub(start_size);
                if cmd_size == netbios_len {
                    break;
                }
            }
        }
    }

    async fn s2c_parser_inner(
        strm: *mut PktStrm<T>,
        cb_smb: SmbCallbacks,
        cb_ctx: *mut c_void,
        valid_ver: ValidVer,
        encrypt: EncryptMng,
    ) -> Result<(), ()> {
        let stm = unsafe { &mut *strm };

        loop {
            let (byte, _seq) = stm.readn(4).await?;
            let netbios_len = BigEndian::read_u24(&byte[1..4]) as usize;
            let start_size = stm.get_read_size();
            loop {
                let header = Self::header(stm).await?;
                match header.command {
                    command::NEGOTIATE => {
                        let ver_valiad = Self::peek_negotiate_rsp(stm).await?;
                        if !ver_valiad {
                            valid_ver.set(false).map_err(|_| ())?;
                            return Err(());
                        }
                        valid_ver.set(true).map_err(|_| ())?;

                        Self::consume(stm, netbios_len - HEADER_SIZE as usize).await?
                    }
                    command::SESSION_SETUP => {
                        let ecypt = Self::session_setup_rsp(stm).await?;
                        if ecypt {
                            encrypt.set(true).map_err(|_| ())?;
                            return Err(());
                        }
                        encrypt.set(false).map_err(|_| ())?;
                    }
                    command::READ => Self::read_rsp(stm, header, &cb_smb, cb_ctx).await?,
                    _ => Self::consume(stm, netbios_len - HEADER_SIZE as usize).await?,
                }

                let cmd_size = stm.get_read_size().saturating_sub(start_size);
                if cmd_size == netbios_len {
                    break;
                }
            }
        }
    }

    async fn header(stm: &mut PktStrm<T>) -> Result<SmbHeader, ()> {
        let (byte, _seq) = stm.readn(HEADER_SIZE as usize).await?;

        let protocol_id = LittleEndian::read_u32(&byte[0..4]);
        let structure_size = LittleEndian::read_u16(&byte[4..6]);
        let credit_charge = LittleEndian::read_u16(&byte[6..8]);
        let status = LittleEndian::read_u32(&byte[8..12]);
        let command = LittleEndian::read_u16(&byte[12..14]);
        let credit = LittleEndian::read_u16(&byte[14..16]);
        let flags = LittleEndian::read_u32(&byte[16..20]);
        let next_command = LittleEndian::read_u32(&byte[20..24]);
        let message_id = LittleEndian::read_u64(&byte[24..32]);
        let reserved = LittleEndian::read_u32(&byte[32..36]);
        let tree_id = LittleEndian::read_u32(&byte[36..40]);
        let session_id = LittleEndian::read_u64(&byte[40..48]);
        let signature = LittleEndian::read_u128(&byte[48..64]);

        Ok(SmbHeader {
            protocol_id,
            structure_size,
            credit_charge,
            status,
            command,
            credit,
            flags,
            next_command,
            message_id,
            reserved,
            tree_id,
            session_id,
            signature,
        })
    }

    async fn read_req(
        stm: &mut PktStrm<T>,
        header: SmbHeader,
        cb_smb: &SmbCallbacks,
        cb_ctx: *mut c_void,
    ) -> Result<(), ()> {
        let (bytes, _seq) = stm.readn(48).await?;

        let len: u32 = LittleEndian::read_u32(&bytes[4..8]);
        let off: u64 = LittleEndian::read_u64(&bytes[8..16]);
        let fid: u128 = LittleEndian::read_u128(&bytes[16..32]);

        if let Some(ref cb) = cb_smb.file_start {
            cb.borrow_mut()(&header, len, off, fid, cb_ctx);
        }

        let channel_len: u16 = LittleEndian::read_u16(&bytes[46..48]);
        if channel_len == 0 {
            let (_bytes, _seq) = stm.readn(1).await?;
        } else {
            Self::consume(stm, channel_len.into()).await?;
        }
        Ok(())
    }

    async fn write_req(
        stm: &mut PktStrm<T>,
        header: SmbHeader,
        cb_smb: &SmbCallbacks,
        cb_ctx: *mut c_void,
    ) -> Result<(), ()> {
        let (bytes, _seq) = stm.readn(48).await?;

        let len: u32 = LittleEndian::read_u32(&bytes[4..8]);
        let off: u64 = LittleEndian::read_u64(&bytes[8..16]);
        let fid: u128 = LittleEndian::read_u128(&bytes[16..32]);

        if let Some(ref cb) = cb_smb.file_start {
            cb.borrow_mut()(&header, len, off, fid, cb_ctx);
        }

        if len == 0 {
            let (_bytes, _seq) = stm.readn(1).await?;
        } else {
            let mut remain_size = len as usize;
            while remain_size > 0 {
                let (bytes, seq) = stm.read(remain_size).await?;

                if let Some(ref cb) = cb_smb.file {
                    cb.borrow_mut()(bytes, seq, cb_ctx);
                }

                remain_size -= bytes.len();
            }
            if let Some(ref cb) = cb_smb.file_stop {
                cb.borrow_mut()(&header, cb_ctx);
            }
        }
        Ok(())
    }

    async fn peek_negotiate_rsp(stm: &mut PktStrm<T>) -> Result<bool, ()> {
        let bytes = stm.peekn(6).await?;

        let ver: u16 = LittleEndian::read_u16(&bytes[4..6]);
        let is_valid = matches!(ver, 0x0202 | 0x0210 | 0x0300 | 0x0302 | 0x0311);
        Ok(is_valid)
    }

    async fn session_setup_rsp(stm: &mut PktStrm<T>) -> Result<bool, ()> {
        let (bytes, _seq) = stm.readn(8).await?;

        let flags: u16 = LittleEndian::read_u16(&bytes[2..4]);
        let buff_len: u16 = LittleEndian::read_u16(&bytes[6..8]);

        Self::consume(stm, buff_len.into()).await?;

        let ret = (flags & SESSION_FLAG_ENCRYPT_DATA) == SESSION_FLAG_ENCRYPT_DATA;
        Ok(ret)
    }

    async fn read_rsp(
        stm: &mut PktStrm<T>,
        header: SmbHeader,
        cb_smb: &SmbCallbacks,
        cb_ctx: *mut c_void,
    ) -> Result<(), ()> {
        let (bytes, _seq) = stm.readn(16).await?;

        let data_len: u32 = LittleEndian::read_u32(&bytes[4..8]);

        if data_len == 0 {
            let (_bytes, _seq) = stm.readn(1).await?;
        } else {
            let mut remain_size = data_len as usize;
            while remain_size > 0 {
                let (bytes, seq) = stm.read(remain_size).await?;

                if let Some(ref cb) = cb_smb.file {
                    cb.borrow_mut()(bytes, seq, cb_ctx);
                }

                remain_size -= bytes.len();
            }
            if let Some(ref cb) = cb_smb.file_stop {
                cb.borrow_mut()(&header, cb_ctx);
            }
        }
        Ok(())
    }

    async fn consume(stm: &mut PktStrm<T>, size: usize) -> Result<(), ()> {
        let mut remain_size = size;
        while remain_size > 0 {
            let (bytes, _seq) = stm.read(remain_size).await?;
            remain_size -= bytes.len();
        }
        Ok(())
    }
}

impl<T> Parser for SmbParser<T>
where
    T: Packet + 'static,
{
    type T = T;

    fn dir_confirm(&self) -> DirConfirmFn<Self::T> {
        |c2s_strm, s2c_strm, c2s_port, s2c_port| {
            let stm_c2s = unsafe { &mut *c2s_strm };
            let stm_s2c = unsafe { &mut *s2c_strm };

            if s2c_port == SMB_PORT {
                return Some(true);
            } else if c2s_port == SMB_PORT {
                return Some(false);
            }

            let payload_c2s = stm_c2s.peek_payload();
            let payload_s2c = stm_s2c.peek_payload();

            if payload_c2s.is_err() && payload_s2c.is_err() {
                return None;
            }

            if let Ok(payload) = payload_c2s {
                if payload.len() >= 32 {
                    let flags = LittleEndian::read_u32(&payload[28..32]);
                    if (flags & HEADER_FLAGS_SERVER_TO_REDIR) == 0 {
                        return Some(true);
                    } else {
                        return Some(false);
                    }
                }
            }

            if let Ok(payload) = payload_s2c {
                if payload.len() >= 32 {
                    let flags = LittleEndian::read_u32(&payload[28..32]);
                    if (flags & HEADER_FLAGS_SERVER_TO_REDIR) == 1 {
                        return Some(true);
                    } else {
                        return Some(false);
                    }
                }
            }

            Some(true)
        }
    }

    fn c2s_parser(&self, strm: *mut PktStrm<T>, cb_ctx: *mut c_void) -> Option<ParserFuture> {
        let cb = SmbCallbacks {
            file_start: self.cb_file_start.clone(),
            file: self.cb_file.clone(),
            file_stop: self.cb_file_stop.clone(),
        };
        let valid_ver = self.version.clone();
        let encrypt = self.encrypt.clone();

        Some(Box::pin(Self::c2s_parser_inner(
            strm, cb, cb_ctx, valid_ver, encrypt,
        )))
    }

    fn s2c_parser(&self, strm: *mut PktStrm<T>, cb_ctx: *mut c_void) -> Option<ParserFuture> {
        let cb = SmbCallbacks {
            file_start: self.cb_file_start.clone(),
            file: self.cb_file.clone(),
            file_stop: self.cb_file_stop.clone(),
        };
        let valid_ver = self.version.clone();
        let encrypt = self.encrypt.clone();

        Some(Box::pin(Self::s2c_parser_inner(
            strm, cb, cb_ctx, valid_ver, encrypt,
        )))
    }
}

pub(crate) struct SmbFactory<T> {
    _phantom_t: PhantomData<T>,
}

impl<T> ParserFactory<T> for SmbFactory<T>
where
    T: Packet + 'static,
{
    fn new() -> Self {
        Self {
            _phantom_t: PhantomData,
        }
    }

    fn create(&self, prolens: &Prolens<T>) -> Box<dyn Parser<T = T>> {
        let mut parser = Box::new(SmbParser::new());
        parser.cb_file_start = prolens.cb_smb_file_start.clone();
        parser.cb_file = prolens.cb_smb_file.clone();
        parser.cb_file_stop = prolens.cb_smb_file_stop.clone();
        parser
    }
}

#[derive(Clone)]
pub(crate) struct SmbCallbacks {
    file_start: Option<CbSmbFileStart>,
    file: Option<CbSmbFile>,
    file_stop: Option<CbSmbFileStop>,
}

pub(crate) type ValidVer = SharedStateManager<bool>;
pub(crate) type EncryptMng = SharedStateManager<bool>;

const HEADER_FLAGS_SERVER_TO_REDIR: u32 = 0x00000001;
const HEADER_SIZE: u16 = 64;
const SESSION_FLAG_ENCRYPT_DATA: u16 = 0x0004;

#[rustfmt::skip]
mod command {
    pub(crate) const NEGOTIATE:     u16 = 0x0000;
    pub(crate) const SESSION_SETUP: u16 = 0x0001;
    pub(crate) const READ:          u16 = 0x0008;
    pub(crate) const WRITE:         u16 = 0x0009;
}

#[derive(Debug, Clone)]
pub struct SmbHeader {
    pub protocol_id: u32,
    pub structure_size: u16,
    pub credit_charge: u16,
    pub status: u32,
    pub command: u16,
    pub credit: u16,
    pub flags: u32,
    pub next_command: u32,
    pub message_id: u64,
    pub reserved: u32,
    pub tree_id: u32,
    pub session_id: u64,
    pub signature: u128,
}

#[cfg(test)]
mod tests {
    use super::*;
    use crate::test_utils::*;
    use std::cell::RefCell;
    use std::collections::HashMap;
    use std::env;
    use std::ffi::c_void;
    use std::rc::Rc;
    use std::time::{SystemTime, UNIX_EPOCH};

    #[test]
    fn test_smb_parser() {
        let project_root = env::current_dir().unwrap();
        let file_path = project_root.join("tests/pcap/smb3.pcap");
        let mut cap = Capture::init(file_path).unwrap();

        let expected_content_path = project_root.join("tests/pcap/smb_read.txt");
        let expected_content =
            std::fs::read_to_string(expected_content_path).expect("Failed to read smb_read.txt");

        let captured_file_starts = Rc::new(RefCell::new(Vec::<(SmbHeader, u32, u64, u128)>::new()));
        let captured_file_data = Rc::new(RefCell::new(HashMap::<u128, Vec<u8>>::new()));
        let captured_file_stops = Rc::new(RefCell::new(Vec::<SmbHeader>::new()));
        let current_fid = Rc::new(RefCell::new(None::<u128>));

        let file_start_callback = {
            let starts_clone = captured_file_starts.clone();
            let fid_clone = current_fid.clone();
            let data_clone = captured_file_data.clone();
            move |header: &SmbHeader, len: u32, offset: u64, fid: u128, _cb_ctx: *mut c_void| {
                let mut starts_guard = starts_clone.borrow_mut();
                starts_guard.push((header.clone(), len, offset, fid));

                // Set current FID for data collection
                let mut fid_guard = fid_clone.borrow_mut();
                *fid_guard = Some(fid);

                // Initialize data storage for this FID if not exists
                let mut data_guard = data_clone.borrow_mut();
                data_guard.entry(fid).or_default();

                println!(
                    "SMB File Start: command=0x{:04x}, len={}, offset={}, fid=0x{:032x}",
                    header.command, len, offset, fid
                );
            }
        };

        let file_data_callback = {
            let data_clone = captured_file_data.clone();
            let fid_clone = current_fid.clone();
            move |data: &[u8], _seq: u32, _cb_ctx: *mut c_void| {
                let fid_guard = fid_clone.borrow();
                if let Some(fid) = *fid_guard {
                    let mut data_guard = data_clone.borrow_mut();
                    if let Some(file_data) = data_guard.get_mut(&fid) {
                        file_data.extend_from_slice(data);
                    }
                }
                println!("SMB File Data: {} bytes received", data.len());
            }
        };

        let file_stop_callback = {
            let stops_clone = captured_file_stops.clone();
            let fid_clone = current_fid.clone();
            move |header: &SmbHeader, _cb_ctx: *mut c_void| {
                let mut stops_guard = stops_clone.borrow_mut();
                stops_guard.push(header.clone());

                // Clear current FID
                let mut fid_guard = fid_clone.borrow_mut();
                *fid_guard = None;

                println!("SMB File Stop: command=0x{:04x}\n", header.command);
            }
        };

        let mut protolens = Prolens::<CapPacket>::default();
        protolens.set_cb_smb_file_start(file_start_callback);
        protolens.set_cb_smb_file(file_data_callback);
        protolens.set_cb_smb_file_stop(file_stop_callback);

        let mut task = protolens.new_task(TransProto::Tcp);
        protolens.set_task_parser(&mut task, L7Proto::Smb);

        loop {
            let now = SystemTime::now()
                .duration_since(UNIX_EPOCH)
                .unwrap()
                .as_millis();
            let pkt = cap.next_packet(now);
            if pkt.is_none() {
                break;
            }
            let pkt = pkt.unwrap();
            if pkt.decode().is_err() {
                continue;
            }

            protolens.run_task(&mut task, pkt);
        }

        let starts_guard = captured_file_starts.borrow();
        let data_guard = captured_file_data.borrow();
        let stops_guard = captured_file_stops.borrow();

        // Verify basic statistics
        println!("Captured {} file start events", starts_guard.len());
        let total_data_bytes: usize = data_guard.values().map(|v| v.len()).sum();
        println!(
            "Captured {} bytes of file data across {} files",
            total_data_bytes,
            data_guard.len()
        );
        println!("Captured {} file stop events", stops_guard.len());

        assert_eq!(5, starts_guard.len());
        assert_eq!(3975, total_data_bytes);
        assert_eq!(5, stops_guard.len());

        // Verify READ operations
        let read_operations: Vec<_> = starts_guard
            .iter()
            .filter(|(header, _, _, _)| header.command == command::READ)
            .collect();

        assert!(
            !read_operations.is_empty(),
            "Should have at least one READ operation"
        );
        println!("Found {} READ operations", read_operations.len());

        // Find the specific large file read operation (len=3519, fid=0x000000006843c46e0000000076045775)
        let target_fid = 0x000000006843c46e0000000076045775u128;
        let large_read_op = starts_guard.iter().find(|(header, len, offset, fid)| {
            header.command == command::READ && *len == 3519 && *offset == 0 && *fid == target_fid
        });

        assert!(
            large_read_op.is_some(),
            "Should find the large READ operation with len=3519 and target FID"
        );
        println!(
            "Found target large READ operation: len=3519, fid=0x{:032x}",
            target_fid
        );

        // Verify the content of the large file read
        if let Some(large_file_data) = data_guard.get(&target_fid) {
            let received_content = String::from_utf8_lossy(large_file_data);
            println!("Large file content length: {}", received_content.len());
            println!("Expected file content length: {}", expected_content.len());

            // Verify that the read content matches expected content from smb_read.txt
            assert_eq!(
                received_content.trim(),
                expected_content.trim(),
                "Large file read content should match expected content from smb_read.txt"
            );

            println!("✓ Large file content verification passed");
        } else {
            panic!("No data found for the target large file read operation");
        }

        // Verify file operations are properly paired
        assert_eq!(
            starts_guard.len(),
            stops_guard.len(),
            "File start and stop events should be paired"
        );

        // Print summary of all file operations
        println!("\nFile operations summary:");
        for (i, (header, len, offset, fid)) in starts_guard.iter().enumerate() {
            let data_len = data_guard.get(fid).map(|v| v.len()).unwrap_or(0);
            println!(
                "  {}: command=0x{:04x}, len={}, offset={}, fid=0x{:032x}, actual_data={} bytes",
                i + 1,
                header.command,
                len,
                offset,
                fid,
                data_len
            );
        }
    }
}