1 /** @file
2 This module contains EBC support routines that are customized based on
3 the target ia32 processor.
4
5 Copyright (c) 2006 - 2014, Intel Corporation. All rights reserved.<BR>
6 This program and the accompanying materials
7 are licensed and made available under the terms and conditions of the BSD License
8 which accompanies this distribution. The full text of the license may be found at
9 http://opensource.org/licenses/bsd-license.php
10
11 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
12 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
13
14 **/
15
16 #include "EbcInt.h"
17 #include "EbcExecute.h"
18 #include "EbcDebuggerHook.h"
19
20 //
21 // NOTE: This is the stack size allocated for the interpreter
22 // when it executes an EBC image. The requirements can change
23 // based on whether or not a debugger is present, and other
24 // platform-specific configurations.
25 //
26 #define VM_STACK_SIZE (1024 * 4)
27
28 #define STACK_REMAIN_SIZE (1024 * 4)
29
30 //
31 // This is instruction buffer used to create EBC thunk
32 //
33 #define EBC_ENTRYPOINT_SIGNATURE 0xAFAFAFAF
34 #define EBC_LL_EBC_ENTRYPOINT_SIGNATURE 0xFAFAFAFA
35 UINT8 mInstructionBufferTemplate[] = {
36 //
37 // Add a magic code here to help the VM recognize the thunk..
38 // mov eax, 0xca112ebc => B8 BC 2E 11 CA
39 //
40 0xB8, 0xBC, 0x2E, 0x11, 0xCA,
41 //
42 // Add code bytes to load up a processor register with the EBC entry point.
43 // mov eax, EbcEntryPoint => B8 XX XX XX XX (To be fixed at runtime)
44 // These 4 bytes of the thunk entry is the address of the EBC
45 // entry point.
46 //
47 0xB8,
48 (UINT8)(EBC_ENTRYPOINT_SIGNATURE & 0xFF),
49 (UINT8)((EBC_ENTRYPOINT_SIGNATURE >> 8) & 0xFF),
50 (UINT8)((EBC_ENTRYPOINT_SIGNATURE >> 16) & 0xFF),
51 (UINT8)((EBC_ENTRYPOINT_SIGNATURE >> 24) & 0xFF),
52 //
53 // Stick in a load of ecx with the address of appropriate VM function.
54 // mov ecx, EbcLLEbcInterpret => B9 XX XX XX XX (To be fixed at runtime)
55 //
56 0xB9,
57 (UINT8)(EBC_LL_EBC_ENTRYPOINT_SIGNATURE & 0xFF),
58 (UINT8)((EBC_LL_EBC_ENTRYPOINT_SIGNATURE >> 8) & 0xFF),
59 (UINT8)((EBC_LL_EBC_ENTRYPOINT_SIGNATURE >> 16) & 0xFF),
60 (UINT8)((EBC_LL_EBC_ENTRYPOINT_SIGNATURE >> 24) & 0xFF),
61 //
62 // Stick in jump opcode bytes
63 // jmp ecx => FF E1
64 //
65 0xFF, 0xE1,
66 };
67
68 /**
69 Begin executing an EBC image.
70 This is used for Ebc Thunk call.
71
72 @return The value returned by the EBC application we're going to run.
73
74 **/
75 UINT64
76 EFIAPI
77 EbcLLEbcInterpret (
78 VOID
79 );
80
81 /**
82 Begin executing an EBC image.
83 This is used for Ebc image entrypoint.
84
85 @return The value returned by the EBC application we're going to run.
86
87 **/
88 UINT64
89 EFIAPI
90 EbcLLExecuteEbcImageEntryPoint (
91 VOID
92 );
93
94 /**
95 This function is called to execute an EBC CALLEX instruction.
96 The function check the callee's content to see whether it is common native
97 code or a thunk to another piece of EBC code.
98 If the callee is common native code, use EbcLLCAllEXASM to manipulate,
99 otherwise, set the VM->IP to target EBC code directly to avoid another VM
100 be startup which cost time and stack space.
101
102 @param VmPtr Pointer to a VM context.
103 @param FuncAddr Callee's address
104 @param NewStackPointer New stack pointer after the call
105 @param FramePtr New frame pointer after the call
106 @param Size The size of call instruction
107
108 **/
109 VOID
EbcLLCALLEX(IN VM_CONTEXT * VmPtr,IN UINTN FuncAddr,IN UINTN NewStackPointer,IN VOID * FramePtr,IN UINT8 Size)110 EbcLLCALLEX (
111 IN VM_CONTEXT *VmPtr,
112 IN UINTN FuncAddr,
113 IN UINTN NewStackPointer,
114 IN VOID *FramePtr,
115 IN UINT8 Size
116 )
117 {
118 UINTN IsThunk;
119 UINTN TargetEbcAddr;
120 UINT8 InstructionBuffer[sizeof(mInstructionBufferTemplate)];
121 UINTN Index;
122 UINTN IndexOfEbcEntrypoint;
123
124 IsThunk = 1;
125 TargetEbcAddr = 0;
126 IndexOfEbcEntrypoint = 0;
127
128 //
129 // Processor specific code to check whether the callee is a thunk to EBC.
130 //
131 CopyMem (InstructionBuffer, (VOID *)FuncAddr, sizeof(InstructionBuffer));
132 //
133 // Fill the signature according to mInstructionBufferTemplate
134 //
135 for (Index = 0; Index < sizeof(mInstructionBufferTemplate) - sizeof(UINTN); Index++) {
136 if (*(UINTN *)&mInstructionBufferTemplate[Index] == EBC_ENTRYPOINT_SIGNATURE) {
137 *(UINTN *)&InstructionBuffer[Index] = EBC_ENTRYPOINT_SIGNATURE;
138 IndexOfEbcEntrypoint = Index;
139 }
140 if (*(UINTN *)&mInstructionBufferTemplate[Index] == EBC_LL_EBC_ENTRYPOINT_SIGNATURE) {
141 *(UINTN *)&InstructionBuffer[Index] = EBC_LL_EBC_ENTRYPOINT_SIGNATURE;
142 }
143 }
144 //
145 // Check if we need thunk to native
146 //
147 if (CompareMem (InstructionBuffer, mInstructionBufferTemplate, sizeof(mInstructionBufferTemplate)) != 0) {
148 IsThunk = 0;
149 }
150
151 if (IsThunk == 1){
152 //
153 // The callee is a thunk to EBC, adjust the stack pointer down 16 bytes and
154 // put our return address and frame pointer on the VM stack.
155 // Then set the VM's IP to new EBC code.
156 //
157 VmPtr->Gpr[0] -= 8;
158 VmWriteMemN (VmPtr, (UINTN) VmPtr->Gpr[0], (UINTN) FramePtr);
159 VmPtr->FramePtr = (VOID *) (UINTN) VmPtr->Gpr[0];
160 VmPtr->Gpr[0] -= 8;
161 VmWriteMem64 (VmPtr, (UINTN) VmPtr->Gpr[0], (UINT64) (UINTN) (VmPtr->Ip + Size));
162
163 CopyMem (&TargetEbcAddr, (UINT8 *)FuncAddr + IndexOfEbcEntrypoint, sizeof(UINTN));
164 VmPtr->Ip = (VMIP) (UINTN) TargetEbcAddr;
165 } else {
166 //
167 // The callee is not a thunk to EBC, call native code,
168 // and get return value.
169 //
170 VmPtr->Gpr[7] = EbcLLCALLEXNative (FuncAddr, NewStackPointer, FramePtr);
171
172 //
173 // Advance the IP.
174 //
175 VmPtr->Ip += Size;
176 }
177 }
178
179
180 /**
181 Begin executing an EBC image.
182
183 This is a thunk function. Microsoft x64 compiler only provide fast_call
184 calling convention, so the first four arguments are passed by rcx, rdx,
185 r8, and r9, while other arguments are passed in stack.
186
187 @param EntryPoint The entrypoint of EBC code.
188 @param Arg1 The 1st argument.
189 @param Arg2 The 2nd argument.
190 @param Arg3 The 3rd argument.
191 @param Arg4 The 4th argument.
192 @param Arg5 The 5th argument.
193 @param Arg6 The 6th argument.
194 @param Arg7 The 7th argument.
195 @param Arg8 The 8th argument.
196 @param Arg9 The 9th argument.
197 @param Arg10 The 10th argument.
198 @param Arg11 The 11th argument.
199 @param Arg12 The 12th argument.
200 @param Arg13 The 13th argument.
201 @param Arg14 The 14th argument.
202 @param Arg15 The 15th argument.
203 @param Arg16 The 16th argument.
204
205 @return The value returned by the EBC application we're going to run.
206
207 **/
208 UINT64
209 EFIAPI
EbcInterpret(IN UINTN EntryPoint,IN UINTN Arg1,IN UINTN Arg2,IN UINTN Arg3,IN UINTN Arg4,IN UINTN Arg5,IN UINTN Arg6,IN UINTN Arg7,IN UINTN Arg8,IN UINTN Arg9,IN UINTN Arg10,IN UINTN Arg11,IN UINTN Arg12,IN UINTN Arg13,IN UINTN Arg14,IN UINTN Arg15,IN UINTN Arg16)210 EbcInterpret (
211 IN UINTN EntryPoint,
212 IN UINTN Arg1,
213 IN UINTN Arg2,
214 IN UINTN Arg3,
215 IN UINTN Arg4,
216 IN UINTN Arg5,
217 IN UINTN Arg6,
218 IN UINTN Arg7,
219 IN UINTN Arg8,
220 IN UINTN Arg9,
221 IN UINTN Arg10,
222 IN UINTN Arg11,
223 IN UINTN Arg12,
224 IN UINTN Arg13,
225 IN UINTN Arg14,
226 IN UINTN Arg15,
227 IN UINTN Arg16
228 )
229 {
230 //
231 // Create a new VM context on the stack
232 //
233 VM_CONTEXT VmContext;
234 UINTN Addr;
235 EFI_STATUS Status;
236 UINTN StackIndex;
237
238 //
239 // Get the EBC entry point
240 //
241 Addr = EntryPoint;
242
243 //
244 // Now clear out our context
245 //
246 ZeroMem ((VOID *) &VmContext, sizeof (VM_CONTEXT));
247
248 //
249 // Set the VM instruction pointer to the correct location in memory.
250 //
251 VmContext.Ip = (VMIP) Addr;
252 //
253 // Initialize the stack pointer for the EBC. Get the current system stack
254 // pointer and adjust it down by the max needed for the interpreter.
255 //
256
257 //
258 // Align the stack on a natural boundary
259 //
260
261 //
262 // Allocate stack pool
263 //
264 Status = GetEBCStack((EFI_HANDLE)-1, &VmContext.StackPool, &StackIndex);
265 if (EFI_ERROR(Status)) {
266 return Status;
267 }
268 VmContext.StackTop = (UINT8*)VmContext.StackPool + (STACK_REMAIN_SIZE);
269 VmContext.Gpr[0] = (UINT64)(UINTN) ((UINT8*)VmContext.StackPool + STACK_POOL_SIZE);
270 VmContext.HighStackBottom = (UINTN)VmContext.Gpr[0];
271 VmContext.Gpr[0] &= ~((VM_REGISTER)(sizeof (UINTN) - 1));
272 VmContext.Gpr[0] -= sizeof (UINTN);
273
274 //
275 // Put a magic value in the stack gap, then adjust down again
276 //
277 *(UINTN *) (UINTN) (VmContext.Gpr[0]) = (UINTN) VM_STACK_KEY_VALUE;
278 VmContext.StackMagicPtr = (UINTN *) (UINTN) VmContext.Gpr[0];
279 VmContext.LowStackTop = (UINTN) VmContext.Gpr[0];
280
281 //
282 // For IA32, this is where we say our return address is
283 //
284 VmContext.Gpr[0] -= sizeof (UINTN);
285 *(UINTN *) (UINTN) (VmContext.Gpr[0]) = (UINTN) Arg16;
286 VmContext.Gpr[0] -= sizeof (UINTN);
287 *(UINTN *) (UINTN) (VmContext.Gpr[0]) = (UINTN) Arg15;
288 VmContext.Gpr[0] -= sizeof (UINTN);
289 *(UINTN *) (UINTN) (VmContext.Gpr[0]) = (UINTN) Arg14;
290 VmContext.Gpr[0] -= sizeof (UINTN);
291 *(UINTN *) (UINTN) (VmContext.Gpr[0]) = (UINTN) Arg13;
292 VmContext.Gpr[0] -= sizeof (UINTN);
293 *(UINTN *) (UINTN) (VmContext.Gpr[0]) = (UINTN) Arg12;
294 VmContext.Gpr[0] -= sizeof (UINTN);
295 *(UINTN *) (UINTN) (VmContext.Gpr[0]) = (UINTN) Arg11;
296 VmContext.Gpr[0] -= sizeof (UINTN);
297 *(UINTN *) (UINTN) (VmContext.Gpr[0]) = (UINTN) Arg10;
298 VmContext.Gpr[0] -= sizeof (UINTN);
299 *(UINTN *) (UINTN) (VmContext.Gpr[0]) = (UINTN) Arg9;
300 VmContext.Gpr[0] -= sizeof (UINTN);
301 *(UINTN *) (UINTN) (VmContext.Gpr[0]) = (UINTN) Arg8;
302 VmContext.Gpr[0] -= sizeof (UINTN);
303 *(UINTN *) (UINTN) (VmContext.Gpr[0]) = (UINTN) Arg7;
304 VmContext.Gpr[0] -= sizeof (UINTN);
305 *(UINTN *) (UINTN) (VmContext.Gpr[0]) = (UINTN) Arg6;
306 VmContext.Gpr[0] -= sizeof (UINTN);
307 *(UINTN *) (UINTN) (VmContext.Gpr[0]) = (UINTN) Arg5;
308 VmContext.Gpr[0] -= sizeof (UINTN);
309 *(UINTN *) (UINTN) (VmContext.Gpr[0]) = (UINTN) Arg4;
310 VmContext.Gpr[0] -= sizeof (UINTN);
311 *(UINTN *) (UINTN) (VmContext.Gpr[0]) = (UINTN) Arg3;
312 VmContext.Gpr[0] -= sizeof (UINTN);
313 *(UINTN *) (UINTN) (VmContext.Gpr[0]) = (UINTN) Arg2;
314 VmContext.Gpr[0] -= sizeof (UINTN);
315 *(UINTN *) (UINTN) (VmContext.Gpr[0]) = (UINTN) Arg1;
316 VmContext.Gpr[0] -= 16;
317 VmContext.StackRetAddr = (UINT64) VmContext.Gpr[0];
318
319 //
320 // We need to keep track of where the EBC stack starts. This way, if the EBC
321 // accesses any stack variables above its initial stack setting, then we know
322 // it's accessing variables passed into it, which means the data is on the
323 // VM's stack.
324 // When we're called, on the stack (high to low) we have the parameters, the
325 // return address, then the saved ebp. Save the pointer to the return address.
326 // EBC code knows that's there, so should look above it for function parameters.
327 // The offset is the size of locals (VMContext + Addr + saved ebp).
328 // Note that the interpreter assumes there is a 16 bytes of return address on
329 // the stack too, so adjust accordingly.
330 // VmContext.HighStackBottom = (UINTN)(Addr + sizeof (VmContext) + sizeof (Addr));
331 //
332
333 //
334 // Begin executing the EBC code
335 //
336 EbcDebuggerHookEbcInterpret (&VmContext);
337 EbcExecute (&VmContext);
338
339 //
340 // Return the value in Gpr[7] unless there was an error
341 //
342 ReturnEBCStack(StackIndex);
343 return (UINT64) VmContext.Gpr[7];
344 }
345
346
347 /**
348 Begin executing an EBC image.
349
350 @param EntryPoint The entrypoint of EBC code.
351 @param ImageHandle image handle for the EBC application we're executing
352 @param SystemTable standard system table passed into an driver's entry
353 point
354
355 @return The value returned by the EBC application we're going to run.
356
357 **/
358 UINT64
359 EFIAPI
ExecuteEbcImageEntryPoint(IN UINTN EntryPoint,IN EFI_HANDLE ImageHandle,IN EFI_SYSTEM_TABLE * SystemTable)360 ExecuteEbcImageEntryPoint (
361 IN UINTN EntryPoint,
362 IN EFI_HANDLE ImageHandle,
363 IN EFI_SYSTEM_TABLE *SystemTable
364 )
365 {
366 //
367 // Create a new VM context on the stack
368 //
369 VM_CONTEXT VmContext;
370 UINTN Addr;
371 EFI_STATUS Status;
372 UINTN StackIndex;
373
374 //
375 // Get the EBC entry point
376 //
377 Addr = EntryPoint;
378
379 //
380 // Now clear out our context
381 //
382 ZeroMem ((VOID *) &VmContext, sizeof (VM_CONTEXT));
383
384 //
385 // Save the image handle so we can track the thunks created for this image
386 //
387 VmContext.ImageHandle = ImageHandle;
388 VmContext.SystemTable = SystemTable;
389
390 //
391 // Set the VM instruction pointer to the correct location in memory.
392 //
393 VmContext.Ip = (VMIP) Addr;
394
395 //
396 // Initialize the stack pointer for the EBC. Get the current system stack
397 // pointer and adjust it down by the max needed for the interpreter.
398 //
399
400 //
401 // Allocate stack pool
402 //
403 Status = GetEBCStack(ImageHandle, &VmContext.StackPool, &StackIndex);
404 if (EFI_ERROR(Status)) {
405 return Status;
406 }
407 VmContext.StackTop = (UINT8*)VmContext.StackPool + (STACK_REMAIN_SIZE);
408 VmContext.Gpr[0] = (UINT64)(UINTN) ((UINT8*)VmContext.StackPool + STACK_POOL_SIZE);
409 VmContext.HighStackBottom = (UINTN)VmContext.Gpr[0];
410 VmContext.Gpr[0] -= sizeof (UINTN);
411
412 //
413 // Put a magic value in the stack gap, then adjust down again
414 //
415 *(UINTN *) (UINTN) (VmContext.Gpr[0]) = (UINTN) VM_STACK_KEY_VALUE;
416 VmContext.StackMagicPtr = (UINTN *) (UINTN) VmContext.Gpr[0];
417
418 //
419 // Align the stack on a natural boundary
420 // VmContext.Gpr[0] &= ~(sizeof(UINTN) - 1);
421 //
422 VmContext.LowStackTop = (UINTN) VmContext.Gpr[0];
423 VmContext.Gpr[0] -= sizeof (UINTN);
424 *(UINTN *) (UINTN) (VmContext.Gpr[0]) = (UINTN) SystemTable;
425 VmContext.Gpr[0] -= sizeof (UINTN);
426 *(UINTN *) (UINTN) (VmContext.Gpr[0]) = (UINTN) ImageHandle;
427
428 VmContext.Gpr[0] -= 16;
429 VmContext.StackRetAddr = (UINT64) VmContext.Gpr[0];
430 //
431 // VM pushes 16-bytes for return address. Simulate that here.
432 //
433
434 //
435 // Begin executing the EBC code
436 //
437 EbcDebuggerHookExecuteEbcImageEntryPoint (&VmContext);
438 EbcExecute (&VmContext);
439
440 //
441 // Return the value in Gpr[7] unless there was an error
442 //
443 ReturnEBCStack(StackIndex);
444 return (UINT64) VmContext.Gpr[7];
445 }
446
447
448 /**
449 Create thunks for an EBC image entry point, or an EBC protocol service.
450
451 @param ImageHandle Image handle for the EBC image. If not null, then
452 we're creating a thunk for an image entry point.
453 @param EbcEntryPoint Address of the EBC code that the thunk is to call
454 @param Thunk Returned thunk we create here
455 @param Flags Flags indicating options for creating the thunk
456
457 @retval EFI_SUCCESS The thunk was created successfully.
458 @retval EFI_INVALID_PARAMETER The parameter of EbcEntryPoint is not 16-bit
459 aligned.
460 @retval EFI_OUT_OF_RESOURCES There is not enough memory to created the EBC
461 Thunk.
462 @retval EFI_BUFFER_TOO_SMALL EBC_THUNK_SIZE is not larger enough.
463
464 **/
465 EFI_STATUS
EbcCreateThunks(IN EFI_HANDLE ImageHandle,IN VOID * EbcEntryPoint,OUT VOID ** Thunk,IN UINT32 Flags)466 EbcCreateThunks (
467 IN EFI_HANDLE ImageHandle,
468 IN VOID *EbcEntryPoint,
469 OUT VOID **Thunk,
470 IN UINT32 Flags
471 )
472 {
473 UINT8 *Ptr;
474 UINT8 *ThunkBase;
475 UINT32 Index;
476 INT32 ThunkSize;
477
478 //
479 // Check alignment of pointer to EBC code
480 //
481 if ((UINT32) (UINTN) EbcEntryPoint & 0x01) {
482 return EFI_INVALID_PARAMETER;
483 }
484
485 ThunkSize = sizeof(mInstructionBufferTemplate);
486
487 Ptr = AllocatePool (sizeof(mInstructionBufferTemplate));
488
489 if (Ptr == NULL) {
490 return EFI_OUT_OF_RESOURCES;
491 }
492 //
493 // Print(L"Allocate TH: 0x%X\n", (UINT32)Ptr);
494 //
495 // Save the start address so we can add a pointer to it to a list later.
496 //
497 ThunkBase = Ptr;
498
499 //
500 // Give them the address of our buffer we're going to fix up
501 //
502 *Thunk = (VOID *) Ptr;
503
504 //
505 // Copy whole thunk instruction buffer template
506 //
507 CopyMem (Ptr, mInstructionBufferTemplate, sizeof(mInstructionBufferTemplate));
508
509 //
510 // Patch EbcEntryPoint and EbcLLEbcInterpret
511 //
512 for (Index = 0; Index < sizeof(mInstructionBufferTemplate) - sizeof(UINTN); Index++) {
513 if (*(UINTN *)&Ptr[Index] == EBC_ENTRYPOINT_SIGNATURE) {
514 *(UINTN *)&Ptr[Index] = (UINTN)EbcEntryPoint;
515 }
516 if (*(UINTN *)&Ptr[Index] == EBC_LL_EBC_ENTRYPOINT_SIGNATURE) {
517 if ((Flags & FLAG_THUNK_ENTRY_POINT) != 0) {
518 *(UINTN *)&Ptr[Index] = (UINTN)EbcLLExecuteEbcImageEntryPoint;
519 } else {
520 *(UINTN *)&Ptr[Index] = (UINTN)EbcLLEbcInterpret;
521 }
522 }
523 }
524
525 //
526 // Add the thunk to the list for this image. Do this last since the add
527 // function flushes the cache for us.
528 //
529 EbcAddImageThunk (ImageHandle, (VOID *) ThunkBase, ThunkSize);
530
531 return EFI_SUCCESS;
532 }
533