xref: /llvm-project/lldb/source/Utility/StringExtractorGDBRemote.cpp (revision 70558d39f01beb87ab561bfaefeecb4d9534beed)
1 //===-- StringExtractorGDBRemote.cpp --------------------------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 #include "lldb/Utility/StringExtractorGDBRemote.h"
10 
11 #include <cctype>
12 #include <cstring>
13 
14 constexpr lldb::pid_t StringExtractorGDBRemote::AllProcesses;
15 constexpr lldb::tid_t StringExtractorGDBRemote::AllThreads;
16 
17 StringExtractorGDBRemote::ResponseType
18 StringExtractorGDBRemote::GetResponseType() const {
19   if (m_packet.empty())
20     return eUnsupported;
21 
22   switch (m_packet[0]) {
23   case 'E':
24     if (isxdigit(m_packet[1]) && isxdigit(m_packet[2])) {
25       if (m_packet.size() == 3)
26         return eError;
27       llvm::StringRef packet_ref(m_packet);
28       if (packet_ref[3] == ';') {
29         auto err_string = packet_ref.substr(4);
30         for (auto e : err_string)
31           if (!isxdigit(e))
32             return eResponse;
33         return eError;
34       }
35     }
36     break;
37 
38   case 'O':
39     if (m_packet.size() == 2 && m_packet[1] == 'K')
40       return eOK;
41     break;
42 
43   case '+':
44     if (m_packet.size() == 1)
45       return eAck;
46     break;
47 
48   case '-':
49     if (m_packet.size() == 1)
50       return eNack;
51     break;
52   }
53   return eResponse;
54 }
55 
56 StringExtractorGDBRemote::ServerPacketType
57 StringExtractorGDBRemote::GetServerPacketType() const {
58 #define PACKET_MATCHES(s)                                                      \
59   ((packet_size == (sizeof(s) - 1)) && (strcmp((packet_cstr), (s)) == 0))
60 #define PACKET_STARTS_WITH(s)                                                  \
61   ((packet_size >= (sizeof(s) - 1)) &&                                         \
62    ::strncmp(packet_cstr, s, (sizeof(s) - 1)) == 0)
63 
64   // Empty is not a supported packet...
65   if (m_packet.empty())
66     return eServerPacketType_invalid;
67 
68   const size_t packet_size = m_packet.size();
69   const char *packet_cstr = m_packet.c_str();
70   switch (m_packet[0]) {
71 
72   case '%':
73     return eServerPacketType_notify;
74 
75   case '\x03':
76     if (packet_size == 1)
77       return eServerPacketType_interrupt;
78     break;
79 
80   case '-':
81     if (packet_size == 1)
82       return eServerPacketType_nack;
83     break;
84 
85   case '+':
86     if (packet_size == 1)
87       return eServerPacketType_ack;
88     break;
89 
90   case 'A':
91     return eServerPacketType_A;
92 
93   case 'Q':
94 
95     switch (packet_cstr[1]) {
96     case 'E':
97       if (PACKET_STARTS_WITH("QEnvironment:"))
98         return eServerPacketType_QEnvironment;
99       if (PACKET_STARTS_WITH("QEnvironmentHexEncoded:"))
100         return eServerPacketType_QEnvironmentHexEncoded;
101       if (PACKET_STARTS_WITH("QEnableErrorStrings"))
102         return eServerPacketType_QEnableErrorStrings;
103       break;
104 
105     case 'P':
106       if (PACKET_STARTS_WITH("QPassSignals:"))
107         return eServerPacketType_QPassSignals;
108       break;
109 
110     case 'S':
111       if (PACKET_MATCHES("QStartNoAckMode"))
112         return eServerPacketType_QStartNoAckMode;
113       if (PACKET_STARTS_WITH("QSaveRegisterState"))
114         return eServerPacketType_QSaveRegisterState;
115       if (PACKET_STARTS_WITH("QSetDisableASLR:"))
116         return eServerPacketType_QSetDisableASLR;
117       if (PACKET_STARTS_WITH("QSetDetachOnError:"))
118         return eServerPacketType_QSetDetachOnError;
119       if (PACKET_STARTS_WITH("QSetSTDIN:"))
120         return eServerPacketType_QSetSTDIN;
121       if (PACKET_STARTS_WITH("QSetSTDOUT:"))
122         return eServerPacketType_QSetSTDOUT;
123       if (PACKET_STARTS_WITH("QSetSTDERR:"))
124         return eServerPacketType_QSetSTDERR;
125       if (PACKET_STARTS_WITH("QSetWorkingDir:"))
126         return eServerPacketType_QSetWorkingDir;
127       if (PACKET_STARTS_WITH("QSetLogging:"))
128         return eServerPacketType_QSetLogging;
129       if (PACKET_STARTS_WITH("QSetMaxPacketSize:"))
130         return eServerPacketType_QSetMaxPacketSize;
131       if (PACKET_STARTS_WITH("QSetMaxPayloadSize:"))
132         return eServerPacketType_QSetMaxPayloadSize;
133       if (PACKET_STARTS_WITH("QSetEnableAsyncProfiling;"))
134         return eServerPacketType_QSetEnableAsyncProfiling;
135       if (PACKET_STARTS_WITH("QSyncThreadState:"))
136         return eServerPacketType_QSyncThreadState;
137       break;
138 
139     case 'L':
140       if (PACKET_STARTS_WITH("QLaunchArch:"))
141         return eServerPacketType_QLaunchArch;
142       if (PACKET_MATCHES("QListThreadsInStopReply"))
143         return eServerPacketType_QListThreadsInStopReply;
144       break;
145 
146     case 'M':
147       if (PACKET_STARTS_WITH("QMemTags"))
148         return eServerPacketType_QMemTags;
149       break;
150 
151     case 'R':
152       if (PACKET_STARTS_WITH("QRestoreRegisterState:"))
153         return eServerPacketType_QRestoreRegisterState;
154       break;
155 
156     case 'T':
157       if (PACKET_MATCHES("QThreadSuffixSupported"))
158         return eServerPacketType_QThreadSuffixSupported;
159       break;
160     }
161     break;
162 
163   case 'q':
164     switch (packet_cstr[1]) {
165     case 's':
166       if (PACKET_MATCHES("qsProcessInfo"))
167         return eServerPacketType_qsProcessInfo;
168       if (PACKET_MATCHES("qsThreadInfo"))
169         return eServerPacketType_qsThreadInfo;
170       break;
171 
172     case 'f':
173       if (PACKET_STARTS_WITH("qfProcessInfo"))
174         return eServerPacketType_qfProcessInfo;
175       if (PACKET_STARTS_WITH("qfThreadInfo"))
176         return eServerPacketType_qfThreadInfo;
177       break;
178 
179     case 'C':
180       if (packet_size == 2)
181         return eServerPacketType_qC;
182       break;
183 
184     case 'E':
185       if (PACKET_STARTS_WITH("qEcho:"))
186         return eServerPacketType_qEcho;
187       break;
188 
189     case 'F':
190       if (PACKET_STARTS_WITH("qFileLoadAddress:"))
191         return eServerPacketType_qFileLoadAddress;
192       break;
193 
194     case 'G':
195       if (PACKET_STARTS_WITH("qGroupName:"))
196         return eServerPacketType_qGroupName;
197       if (PACKET_MATCHES("qGetWorkingDir"))
198         return eServerPacketType_qGetWorkingDir;
199       if (PACKET_MATCHES("qGetPid"))
200         return eServerPacketType_qGetPid;
201       if (PACKET_STARTS_WITH("qGetProfileData;"))
202         return eServerPacketType_qGetProfileData;
203       if (PACKET_MATCHES("qGDBServerVersion"))
204         return eServerPacketType_qGDBServerVersion;
205       break;
206 
207     case 'H':
208       if (PACKET_MATCHES("qHostInfo"))
209         return eServerPacketType_qHostInfo;
210       break;
211 
212     case 'K':
213       if (PACKET_STARTS_WITH("qKillSpawnedProcess"))
214         return eServerPacketType_qKillSpawnedProcess;
215       break;
216 
217     case 'L':
218       if (PACKET_STARTS_WITH("qLaunchGDBServer"))
219         return eServerPacketType_qLaunchGDBServer;
220       if (PACKET_MATCHES("qLaunchSuccess"))
221         return eServerPacketType_qLaunchSuccess;
222       break;
223 
224     case 'M':
225       if (PACKET_STARTS_WITH("qMemoryRegionInfo:"))
226         return eServerPacketType_qMemoryRegionInfo;
227       if (PACKET_MATCHES("qMemoryRegionInfo"))
228         return eServerPacketType_qMemoryRegionInfoSupported;
229       if (PACKET_STARTS_WITH("qModuleInfo:"))
230         return eServerPacketType_qModuleInfo;
231       if (PACKET_STARTS_WITH("qMemTags:"))
232         return eServerPacketType_qMemTags;
233       break;
234 
235     case 'P':
236       if (PACKET_STARTS_WITH("qProcessInfoPID:"))
237         return eServerPacketType_qProcessInfoPID;
238       if (PACKET_STARTS_WITH("qPlatform_shell:"))
239         return eServerPacketType_qPlatform_shell;
240       if (PACKET_STARTS_WITH("qPlatform_mkdir:"))
241         return eServerPacketType_qPlatform_mkdir;
242       if (PACKET_STARTS_WITH("qPlatform_chmod:"))
243         return eServerPacketType_qPlatform_chmod;
244       if (PACKET_MATCHES("qProcessInfo"))
245         return eServerPacketType_qProcessInfo;
246       if (PACKET_STARTS_WITH("qPathComplete:"))
247         return eServerPacketType_qPathComplete;
248       break;
249 
250     case 'Q':
251       if (PACKET_MATCHES("qQueryGDBServer"))
252         return eServerPacketType_qQueryGDBServer;
253       break;
254 
255     case 'R':
256       if (PACKET_STARTS_WITH("qRcmd,"))
257         return eServerPacketType_qRcmd;
258       if (PACKET_STARTS_WITH("qRegisterInfo"))
259         return eServerPacketType_qRegisterInfo;
260       break;
261 
262     case 'S':
263       if (PACKET_STARTS_WITH("qSaveCore"))
264         return eServerPacketType_qLLDBSaveCore;
265       if (PACKET_STARTS_WITH("qSpeedTest:"))
266         return eServerPacketType_qSpeedTest;
267       if (PACKET_MATCHES("qShlibInfoAddr"))
268         return eServerPacketType_qShlibInfoAddr;
269       if (PACKET_MATCHES("qStepPacketSupported"))
270         return eServerPacketType_qStepPacketSupported;
271       if (PACKET_STARTS_WITH("qSupported"))
272         return eServerPacketType_qSupported;
273       if (PACKET_MATCHES("qSyncThreadStateSupported"))
274         return eServerPacketType_qSyncThreadStateSupported;
275       break;
276 
277     case 'T':
278       if (PACKET_STARTS_WITH("qThreadExtraInfo,"))
279         return eServerPacketType_qThreadExtraInfo;
280       if (PACKET_STARTS_WITH("qThreadStopInfo"))
281         return eServerPacketType_qThreadStopInfo;
282       break;
283 
284     case 'U':
285       if (PACKET_STARTS_WITH("qUserName:"))
286         return eServerPacketType_qUserName;
287       break;
288 
289     case 'V':
290       if (PACKET_MATCHES("qVAttachOrWaitSupported"))
291         return eServerPacketType_qVAttachOrWaitSupported;
292       break;
293 
294     case 'W':
295       if (PACKET_STARTS_WITH("qWatchpointSupportInfo:"))
296         return eServerPacketType_qWatchpointSupportInfo;
297       if (PACKET_MATCHES("qWatchpointSupportInfo"))
298         return eServerPacketType_qWatchpointSupportInfoSupported;
299       break;
300 
301     case 'X':
302       if (PACKET_STARTS_WITH("qXfer:"))
303         return eServerPacketType_qXfer;
304       break;
305     }
306     break;
307 
308   case 'j':
309     if (PACKET_STARTS_WITH("jModulesInfo:"))
310       return eServerPacketType_jModulesInfo;
311     if (PACKET_MATCHES("jSignalsInfo"))
312       return eServerPacketType_jSignalsInfo;
313     if (PACKET_MATCHES("jThreadsInfo"))
314       return eServerPacketType_jThreadsInfo;
315 
316     if (PACKET_MATCHES("jLLDBTraceSupported"))
317       return eServerPacketType_jLLDBTraceSupported;
318     if (PACKET_STARTS_WITH("jLLDBTraceStop:"))
319       return eServerPacketType_jLLDBTraceStop;
320     if (PACKET_STARTS_WITH("jLLDBTraceStart:"))
321       return eServerPacketType_jLLDBTraceStart;
322     if (PACKET_STARTS_WITH("jLLDBTraceGetState:"))
323       return eServerPacketType_jLLDBTraceGetState;
324     if (PACKET_STARTS_WITH("jLLDBTraceGetBinaryData:"))
325       return eServerPacketType_jLLDBTraceGetBinaryData;
326     break;
327 
328   case 'v':
329     if (PACKET_STARTS_WITH("vFile:")) {
330       if (PACKET_STARTS_WITH("vFile:open:"))
331         return eServerPacketType_vFile_open;
332       else if (PACKET_STARTS_WITH("vFile:close:"))
333         return eServerPacketType_vFile_close;
334       else if (PACKET_STARTS_WITH("vFile:pread"))
335         return eServerPacketType_vFile_pread;
336       else if (PACKET_STARTS_WITH("vFile:pwrite"))
337         return eServerPacketType_vFile_pwrite;
338       else if (PACKET_STARTS_WITH("vFile:size"))
339         return eServerPacketType_vFile_size;
340       else if (PACKET_STARTS_WITH("vFile:exists"))
341         return eServerPacketType_vFile_exists;
342       else if (PACKET_STARTS_WITH("vFile:stat"))
343         return eServerPacketType_vFile_stat;
344       else if (PACKET_STARTS_WITH("vFile:mode"))
345         return eServerPacketType_vFile_mode;
346       else if (PACKET_STARTS_WITH("vFile:MD5"))
347         return eServerPacketType_vFile_md5;
348       else if (PACKET_STARTS_WITH("vFile:symlink"))
349         return eServerPacketType_vFile_symlink;
350       else if (PACKET_STARTS_WITH("vFile:unlink"))
351         return eServerPacketType_vFile_unlink;
352 
353     } else {
354       if (PACKET_STARTS_WITH("vAttach;"))
355         return eServerPacketType_vAttach;
356       if (PACKET_STARTS_WITH("vAttachWait;"))
357         return eServerPacketType_vAttachWait;
358       if (PACKET_STARTS_WITH("vAttachOrWait;"))
359         return eServerPacketType_vAttachOrWait;
360       if (PACKET_STARTS_WITH("vAttachName;"))
361         return eServerPacketType_vAttachName;
362       if (PACKET_STARTS_WITH("vCont;"))
363         return eServerPacketType_vCont;
364       if (PACKET_MATCHES("vCont?"))
365         return eServerPacketType_vCont_actions;
366     }
367     break;
368   case '_':
369     switch (packet_cstr[1]) {
370     case 'M':
371       return eServerPacketType__M;
372 
373     case 'm':
374       return eServerPacketType__m;
375     }
376     break;
377 
378   case '?':
379     if (packet_size == 1)
380       return eServerPacketType_stop_reason;
381     break;
382 
383   case 'c':
384     return eServerPacketType_c;
385 
386   case 'C':
387     return eServerPacketType_C;
388 
389   case 'D':
390     return eServerPacketType_D;
391 
392   case 'g':
393     return eServerPacketType_g;
394 
395   case 'G':
396     return eServerPacketType_G;
397 
398   case 'H':
399     return eServerPacketType_H;
400 
401   case 'I':
402     return eServerPacketType_I;
403 
404   case 'k':
405     if (packet_size == 1)
406       return eServerPacketType_k;
407     break;
408 
409   case 'm':
410     return eServerPacketType_m;
411 
412   case 'M':
413     return eServerPacketType_M;
414 
415   case 'p':
416     return eServerPacketType_p;
417 
418   case 'P':
419     return eServerPacketType_P;
420 
421   case 's':
422     if (packet_size == 1)
423       return eServerPacketType_s;
424     break;
425 
426   case 'S':
427     return eServerPacketType_S;
428 
429   case 'x':
430     return eServerPacketType_x;
431 
432   case 'X':
433     return eServerPacketType_X;
434 
435   case 'T':
436     return eServerPacketType_T;
437 
438   case 'z':
439     if (packet_cstr[1] >= '0' && packet_cstr[1] <= '4')
440       return eServerPacketType_z;
441     break;
442 
443   case 'Z':
444     if (packet_cstr[1] >= '0' && packet_cstr[1] <= '4')
445       return eServerPacketType_Z;
446     break;
447   }
448   return eServerPacketType_unimplemented;
449 }
450 
451 bool StringExtractorGDBRemote::IsOKResponse() const {
452   return GetResponseType() == eOK;
453 }
454 
455 bool StringExtractorGDBRemote::IsUnsupportedResponse() const {
456   return GetResponseType() == eUnsupported;
457 }
458 
459 bool StringExtractorGDBRemote::IsNormalResponse() const {
460   return GetResponseType() == eResponse;
461 }
462 
463 bool StringExtractorGDBRemote::IsErrorResponse() const {
464   return GetResponseType() == eError && isxdigit(m_packet[1]) &&
465          isxdigit(m_packet[2]);
466 }
467 
468 uint8_t StringExtractorGDBRemote::GetError() {
469   if (GetResponseType() == eError) {
470     SetFilePos(1);
471     return GetHexU8(255);
472   }
473   return 0;
474 }
475 
476 lldb_private::Status StringExtractorGDBRemote::GetStatus() {
477   lldb_private::Status error;
478   if (GetResponseType() == eError) {
479     SetFilePos(1);
480     uint8_t errc = GetHexU8(255);
481     error.SetError(errc, lldb::eErrorTypeGeneric);
482 
483     error.SetErrorStringWithFormat("Error %u", errc);
484     std::string error_messg;
485     if (GetChar() == ';') {
486       GetHexByteString(error_messg);
487       error.SetErrorString(error_messg);
488     }
489   }
490   return error;
491 }
492 
493 size_t StringExtractorGDBRemote::GetEscapedBinaryData(std::string &str) {
494   // Just get the data bytes in the string as
495   // GDBRemoteCommunication::CheckForPacket() already removes any 0x7d escaped
496   // characters. If any 0x7d characters are left in the packet, then they are
497   // supposed to be there...
498   str.clear();
499   const size_t bytes_left = GetBytesLeft();
500   if (bytes_left > 0) {
501     str.assign(m_packet, m_index, bytes_left);
502     m_index += bytes_left;
503   }
504   return str.size();
505 }
506 
507 static bool
508 OKErrorNotSupportedResponseValidator(void *,
509                                      const StringExtractorGDBRemote &response) {
510   switch (response.GetResponseType()) {
511   case StringExtractorGDBRemote::eOK:
512   case StringExtractorGDBRemote::eError:
513   case StringExtractorGDBRemote::eUnsupported:
514     return true;
515 
516   case StringExtractorGDBRemote::eAck:
517   case StringExtractorGDBRemote::eNack:
518   case StringExtractorGDBRemote::eResponse:
519     break;
520   }
521   return false;
522 }
523 
524 static bool JSONResponseValidator(void *,
525                                   const StringExtractorGDBRemote &response) {
526   switch (response.GetResponseType()) {
527   case StringExtractorGDBRemote::eUnsupported:
528   case StringExtractorGDBRemote::eError:
529     return true; // Accept unsupported or EXX as valid responses
530 
531   case StringExtractorGDBRemote::eOK:
532   case StringExtractorGDBRemote::eAck:
533   case StringExtractorGDBRemote::eNack:
534     break;
535 
536   case StringExtractorGDBRemote::eResponse:
537     // JSON that is returned in from JSON query packets is currently always
538     // either a dictionary which starts with a '{', or an array which starts
539     // with a '['. This is a quick validator to just make sure the response
540     // could be valid JSON without having to validate all of the
541     // JSON content.
542     switch (response.GetStringRef()[0]) {
543     case '{':
544       return true;
545     case '[':
546       return true;
547     default:
548       break;
549     }
550     break;
551   }
552   return false;
553 }
554 
555 static bool
556 ASCIIHexBytesResponseValidator(void *,
557                                const StringExtractorGDBRemote &response) {
558   switch (response.GetResponseType()) {
559   case StringExtractorGDBRemote::eUnsupported:
560   case StringExtractorGDBRemote::eError:
561     return true; // Accept unsupported or EXX as valid responses
562 
563   case StringExtractorGDBRemote::eOK:
564   case StringExtractorGDBRemote::eAck:
565   case StringExtractorGDBRemote::eNack:
566     break;
567 
568   case StringExtractorGDBRemote::eResponse: {
569     uint32_t valid_count = 0;
570     for (const char ch : response.GetStringRef()) {
571       if (!isxdigit(ch)) {
572         return false;
573       }
574       if (++valid_count >= 16)
575         break; // Don't validate all the characters in case the packet is very
576                // large
577     }
578     return true;
579   } break;
580   }
581   return false;
582 }
583 
584 void StringExtractorGDBRemote::CopyResponseValidator(
585     const StringExtractorGDBRemote &rhs) {
586   m_validator = rhs.m_validator;
587   m_validator_baton = rhs.m_validator_baton;
588 }
589 
590 void StringExtractorGDBRemote::SetResponseValidator(
591     ResponseValidatorCallback callback, void *baton) {
592   m_validator = callback;
593   m_validator_baton = baton;
594 }
595 
596 void StringExtractorGDBRemote::SetResponseValidatorToOKErrorNotSupported() {
597   m_validator = OKErrorNotSupportedResponseValidator;
598   m_validator_baton = nullptr;
599 }
600 
601 void StringExtractorGDBRemote::SetResponseValidatorToASCIIHexBytes() {
602   m_validator = ASCIIHexBytesResponseValidator;
603   m_validator_baton = nullptr;
604 }
605 
606 void StringExtractorGDBRemote::SetResponseValidatorToJSON() {
607   m_validator = JSONResponseValidator;
608   m_validator_baton = nullptr;
609 }
610 
611 bool StringExtractorGDBRemote::ValidateResponse() const {
612   // If we have a validator callback, try to validate the callback
613   if (m_validator)
614     return m_validator(m_validator_baton, *this);
615   else
616     return true; // No validator, so response is valid
617 }
618 
619 llvm::Optional<std::pair<lldb::pid_t, lldb::tid_t>>
620 StringExtractorGDBRemote::GetPidTid(lldb::pid_t default_pid) {
621   llvm::StringRef view = llvm::StringRef(m_packet).substr(m_index);
622   size_t initial_length = view.size();
623   lldb::pid_t pid = default_pid;
624   lldb::tid_t tid;
625 
626   if (view.consume_front("p")) {
627     // process identifier
628     if (view.consume_front("-1")) {
629       // -1 is a special case
630       pid = AllProcesses;
631     } else if (view.consumeInteger(16, pid) || pid == 0) {
632       // not a valid hex integer OR unsupported pid 0
633       m_index = UINT64_MAX;
634       return llvm::None;
635     }
636 
637     // "." must follow if we expect TID too; otherwise, we assume -1
638     if (!view.consume_front(".")) {
639       // update m_index
640       m_index += initial_length - view.size();
641 
642       return {{pid, AllThreads}};
643     }
644   }
645 
646   // thread identifier
647   if (view.consume_front("-1")) {
648     // -1 is a special case
649     tid = AllThreads;
650   } else if (view.consumeInteger(16, tid) || tid == 0 || pid == AllProcesses) {
651     // not a valid hex integer OR tid 0 OR pid -1 + a specific tid
652     m_index = UINT64_MAX;
653     return llvm::None;
654   }
655 
656   // update m_index
657   m_index += initial_length - view.size();
658 
659   return {{pid, tid}};
660 }
661