xref: /reactos/ntoskrnl/ex/dbgctrl.c (revision 53221834)
1 /*
2  * PROJECT:         ReactOS Kernel
3  * LICENSE:         GPL - See COPYING in the top level directory
4  * FILE:            ntoskrnl/ex/dbgctrl.c
5  * PURPOSE:         System debug control
6  * PROGRAMMERS:     Alex Ionescu
7  */
8 
9 /* INCLUDES *****************************************************************/
10 
11 #include <ntoskrnl.h>
12 #define NDEBUG
13 #include <debug.h>
14 
15 /* DATA **********************************************************************/
16 
17 /*
18  * WinDBG Debugger Worker State Machine data
19  */
20 WORK_QUEUE_ITEM ExpDebuggerWorkItem;
21 /*
22  * The following global variables must be visible through all the kernel
23  * because WinDBG explicitely search for them inside our symbols.
24  */
25 WINKD_WORKER_STATE ExpDebuggerWork;
26 PEPROCESS ExpDebuggerProcessAttach;
27 PEPROCESS ExpDebuggerProcessKill;
28 ULONG_PTR ExpDebuggerPageIn;
29 
30 /* FUNCTIONS *****************************************************************/
31 
32 /*
33  * WinDBG Debugger Worker State Machine
34  *
35  * This functionality is used whenever WinDBG wants to attach or kill a user-mode
36  * process from within live kernel-mode session, and/or page-in an address region.
37  * It is implemented as a state machine: when it is in "Ready" state, WinDBG can
38  * initialize the data for the state machine, then switch its state to "Start".
39  * The worker thread balance manager detects this, switches the state to "Initialized"
40  * and queues a worker thread. As long as the state is not "Ready" again, WinDBG
41  * prevents from requeuing a new thread. When the thread is started, it captures
42  * all the data, then resets the machine state to "Ready", thus allowing WinDBG
43  * to requeue another worker thread.
44  *
45  * WinDBG commands:
46  *     .process /i <addr> (where <addr> is the address of the EPROCESS block for this process)
47  *     .kill <addr>       (       "                "                "                "       )
48  *     .pagein <addr>     (where <addr> is the address to page in)
49  */
50 VOID
51 NTAPI
52 ExpDebuggerWorker(IN PVOID Context)
53 {
54     PEPROCESS ProcessToAttach, ProcessToKill;
55     ULONG_PTR PageInAddress;
56     PEPROCESS Process;
57     KAPC_STATE ApcState;
58 
59     UNREFERENCED_PARAMETER(Context);
60 
61     /* Be sure we were started in an initialized state */
62     ASSERTMSG("ExpDebuggerWorker being entered in non-initialized state!\n",
63               ExpDebuggerWork == WinKdWorkerInitialized);
64     if (ExpDebuggerWork != WinKdWorkerInitialized)
65     {
66         /* An error happened, so get a chance to restart proper */
67         ExpDebuggerWork = WinKdWorkerReady;
68         return;
69     }
70 
71     /* Get the processes to be attached or killed, and the address to page in */
72     ProcessToAttach = ExpDebuggerProcessAttach;
73     ProcessToKill   = ExpDebuggerProcessKill;
74     PageInAddress   = ExpDebuggerPageIn;
75 
76     /* Reset the state machine to its ready state */
77     ExpDebuggerProcessAttach = NULL;
78     ExpDebuggerProcessKill   = NULL;
79     ExpDebuggerPageIn = (ULONG_PTR)NULL;
80     ExpDebuggerWork = WinKdWorkerReady;
81 
82     /* Default to the current process if we don't find the process to be attached or killed */
83     Process = NULL;
84 
85     /* Check if we need to attach or kill some process */
86     if (ProcessToAttach != NULL || ProcessToKill != NULL)
87     {
88         /* Find the process in the list */
89         Process = PsGetNextProcess(Process);
90         while (Process)
91         {
92             /* Is this the process we want to attach to? */
93             if (Process == ProcessToAttach)
94             {
95                 /* Yes, attach ourselves to it */
96                 KeStackAttachProcess(&Process->Pcb, &ApcState);
97                 break;
98             }
99             /* Or is this the process we want to kill? */
100             else if (Process == ProcessToKill)
101             {
102                 /* Yes, kill and dereference it, then return */
103                 PsTerminateProcess(Process, DBG_TERMINATE_PROCESS);
104                 ObDereferenceObject(Process);
105                 return;
106             }
107 
108             /* Get the next process */
109             Process = PsGetNextProcess(Process);
110         }
111 
112         /* We either have found a process, or we default to the current process */
113     }
114 
115     /* If we have an address to page in... */
116     if (PageInAddress)
117     {
118         /* ... try to do it by attempting to read at this address */
119         _SEH2_TRY
120         {
121             ProbeForReadUchar(PageInAddress);
122         }
123         _SEH2_EXCEPT(EXCEPTION_EXECUTE_HANDLER)
124         {
125             DPRINT1("Failed to page in address 0x%p, Status 0x%08lx\n", PageInAddress, _SEH2_GetExceptionCode());
126         }
127         _SEH2_END;
128     }
129 
130     /* Break into the process (or the current one if Process == NULL) */
131     DbgBreakPointWithStatus(DBG_STATUS_WORKER);
132 
133     /* If we are attached to a process, not the current one... */
134     if (Process)
135     {
136         /* ... we can detach from the process */
137         KeUnstackDetachProcess(&ApcState);
138         /* Dereference the process which was referenced for us by PsGetNextProcess */
139         ObDereferenceObject(Process);
140     }
141 }
142 
143 /*++
144  * @name NtSystemDebugControl
145  * @implemented
146  *
147  * Perform various queries to debugger.
148  * This API is subject to test-case creation to further evaluate its
149  * abilities (if needed to at all)
150  *
151  * See: http://www.osronline.com/showthread.cfm?link=93915
152  *      http://void.ru/files/Ntexapi.h
153  *      http://www.codeguru.com/code/legacy/system/ntexapi.zip
154  *      http://www.securityfocus.com/bid/9694
155  *
156  * @param ControlCode
157  *        Description of the parameter. Wrapped to more lines on ~70th
158  *        column.
159  *
160  * @param InputBuffer
161  *        FILLME
162  *
163  * @param InputBufferLength
164  *        FILLME
165  *
166  * @param OutputBuffer
167  *        FILLME
168  *
169  * @param OutputBufferLength
170  *        FILLME
171  *
172   * @param ReturnLength
173  *        FILLME
174  *
175  * @return STATUS_SUCCESS in case of success, proper error code otherwise
176  *
177  * @remarks None
178  *
179  *--*/
180 NTSTATUS
181 NTAPI
182 NtSystemDebugControl(SYSDBG_COMMAND ControlCode,
183                      PVOID InputBuffer,
184                      ULONG InputBufferLength,
185                      PVOID OutputBuffer,
186                      ULONG OutputBufferLength,
187                      PULONG ReturnLength)
188 {
189     switch (ControlCode)
190     {
191         case SysDbgQueryModuleInformation:
192         case SysDbgQueryTraceInformation:
193         case SysDbgSetTracepoint:
194         case SysDbgSetSpecialCall:
195         case SysDbgClearSpecialCalls:
196         case SysDbgQuerySpecialCalls:
197         case SysDbgQueryVersion:
198         case SysDbgReadVirtual:
199         case SysDbgWriteVirtual:
200         case SysDbgReadPhysical:
201         case SysDbgWritePhysical:
202         case SysDbgReadControlSpace:
203         case SysDbgWriteControlSpace:
204         case SysDbgReadIoSpace:
205         case SysDbgWriteIoSpace:
206         case SysDbgReadMsr:
207         case SysDbgWriteMsr:
208         case SysDbgReadBusData:
209         case SysDbgWriteBusData:
210         case SysDbgCheckLowMemory:
211         case SysDbgGetTriageDump:
212             return STATUS_NOT_IMPLEMENTED;
213         case SysDbgBreakPoint:
214         case SysDbgEnableKernelDebugger:
215         case SysDbgDisableKernelDebugger:
216         case SysDbgGetAutoKdEnable:
217         case SysDbgSetAutoKdEnable:
218         case SysDbgGetPrintBufferSize:
219         case SysDbgSetPrintBufferSize:
220         case SysDbgGetKdUmExceptionEnable:
221         case SysDbgSetKdUmExceptionEnable:
222         case SysDbgGetKdBlockEnable:
223         case SysDbgSetKdBlockEnable:
224             return KdSystemDebugControl(
225                 ControlCode,
226                 InputBuffer, InputBufferLength,
227                 OutputBuffer, OutputBufferLength,
228                 ReturnLength, KeGetPreviousMode());
229         default:
230             return STATUS_INVALID_INFO_CLASS;
231     }
232 }
233