1 /** @file 2 PE/Coff Extra Action library instances. 3 4 Copyright (c) 2010 - 2015, Intel Corporation. All rights reserved.<BR> 5 This program and the accompanying materials 6 are licensed and made available under the terms and conditions of the BSD License 7 which accompanies this distribution. The full text of the license may be found at 8 http://opensource.org/licenses/bsd-license.php. 9 10 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS, 11 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED. 12 13 **/ 14 15 #include <PeCoffExtraActionLib.h> 16 17 /** 18 Check if the hardware breakpoint in Drx is enabled by checking the Lx and Gx bit in Dr7. 19 20 It assumes that DebugAgent will set both Lx and Gx bit when setting up the hardware breakpoint. 21 22 23 @param RegisterIndex Index of Dr register. The value range is from 0 to 3. 24 @param Dr7 Value of Dr7 register. 25 26 @return TRUE The hardware breakpoint specified in the Drx is enabled. 27 @return FALSE The hardware breakpoint specified in the Drx is disabled. 28 29 **/ 30 BOOLEAN 31 IsDrxEnabled ( 32 IN UINT8 RegisterIndex, 33 IN UINTN Dr7 34 ) 35 { 36 return (BOOLEAN) (((Dr7 >> (RegisterIndex * 2)) & (BIT0 | BIT1)) == (BIT0 | BIT1)); 37 } 38 39 /** 40 Common routine to report the PE/COFF image loading/relocating or unloading event. 41 42 If ImageContext is NULL, then ASSERT(). 43 44 @param ImageContext Pointer to the image context structure that describes the 45 PE/COFF image. 46 @param Signature IMAGE_LOAD_SIGNATURE or IMAGE_UNLOAD_SIGNATURE. 47 48 **/ 49 VOID 50 PeCoffLoaderExtraActionCommon ( 51 IN OUT PE_COFF_LOADER_IMAGE_CONTEXT *ImageContext, 52 IN UINTN Signature 53 ) 54 { 55 BOOLEAN InterruptState; 56 UINTN Dr0; 57 UINTN Dr1; 58 UINTN Dr2; 59 UINTN Dr3; 60 UINTN Dr7; 61 UINTN Cr4; 62 UINTN NewDr7; 63 UINT8 LoadImageMethod; 64 UINT8 DebugAgentStatus; 65 IA32_DESCRIPTOR IdtDescriptor; 66 IA32_IDT_GATE_DESCRIPTOR OriginalIdtEntry; 67 BOOLEAN IdtEntryHooked; 68 UINT32 RegEdx; 69 70 ASSERT (ImageContext != NULL); 71 72 if (ImageContext->PdbPointer != NULL) { 73 DEBUG((EFI_D_ERROR, " PDB = %a\n", ImageContext->PdbPointer)); 74 } 75 76 // 77 // Disable interrupts and save the current interrupt state 78 // 79 InterruptState = SaveAndDisableInterrupts (); 80 81 IdtEntryHooked = FALSE; 82 LoadImageMethod = PcdGet8 (PcdDebugLoadImageMethod); 83 if (LoadImageMethod == DEBUG_LOAD_IMAGE_METHOD_IO_HW_BREAKPOINT) { 84 // 85 // If the CPU does not support Debug Extensions(CPUID:01 EDX:BIT2) 86 // then force use of DEBUG_LOAD_IMAGE_METHOD_SOFT_INT3 87 // 88 AsmCpuid (1, NULL, NULL, NULL, &RegEdx); 89 if ((RegEdx & BIT2) == 0) { 90 LoadImageMethod = DEBUG_LOAD_IMAGE_METHOD_SOFT_INT3; 91 } 92 } 93 AsmReadIdtr (&IdtDescriptor); 94 if (LoadImageMethod == DEBUG_LOAD_IMAGE_METHOD_SOFT_INT3) { 95 if (!CheckDebugAgentHandler (&IdtDescriptor, SOFT_INT_VECTOR_NUM)) { 96 // 97 // Do not trigger INT3 if Debug Agent did not setup IDT entries. 98 // 99 return; 100 } 101 } else { 102 if (!CheckDebugAgentHandler (&IdtDescriptor, IO_HW_BREAKPOINT_VECTOR_NUM)) { 103 // 104 // Save and update IDT entry for INT1 105 // 106 SaveAndUpdateIdtEntry1 (&IdtDescriptor, &OriginalIdtEntry); 107 IdtEntryHooked = TRUE; 108 } 109 } 110 111 // 112 // Save Debug Register State 113 // 114 Dr0 = AsmReadDr0 (); 115 Dr1 = AsmReadDr1 (); 116 Dr2 = AsmReadDr2 (); 117 Dr3 = AsmReadDr3 (); 118 Dr7 = AsmReadDr7 () | BIT10; // H/w sets bit 10, some simulators don't 119 Cr4 = AsmReadCr4 (); 120 121 // 122 // DR0 = Signature 123 // DR1 = The address of the Null-terminated ASCII string for the PE/COFF image's PDB file name 124 // DR2 = The pointer to the ImageContext structure 125 // DR3 = IO_PORT_BREAKPOINT_ADDRESS 126 // DR7 = Disables all HW breakpoints except for DR3 I/O port access of length 1 byte 127 // CR4 = Make sure DE(BIT3) is set 128 // 129 AsmWriteDr7 (BIT10); 130 AsmWriteDr0 (Signature); 131 AsmWriteDr1 ((UINTN) ImageContext->PdbPointer); 132 AsmWriteDr2 ((UINTN) ImageContext); 133 AsmWriteDr3 (IO_PORT_BREAKPOINT_ADDRESS); 134 135 if (LoadImageMethod == DEBUG_LOAD_IMAGE_METHOD_IO_HW_BREAKPOINT) { 136 AsmWriteDr7 (0x20000480); 137 AsmWriteCr4 (Cr4 | BIT3); 138 // 139 // Do an IN from IO_PORT_BREAKPOINT_ADDRESS to generate a HW breakpoint until the port 140 // returns a read value other than DEBUG_AGENT_IMAGE_WAIT 141 // 142 do { 143 DebugAgentStatus = IoRead8 (IO_PORT_BREAKPOINT_ADDRESS); 144 } while (DebugAgentStatus == DEBUG_AGENT_IMAGE_WAIT); 145 146 } else if (LoadImageMethod == DEBUG_LOAD_IMAGE_METHOD_SOFT_INT3) { 147 // 148 // Generate a software break point. 149 // 150 CpuBreakpoint (); 151 } 152 153 // 154 // Restore Debug Register State only when Host didn't change it inside exception handler. 155 // E.g.: User halts the target and sets the HW breakpoint while target is 156 // in the above exception handler 157 // 158 NewDr7 = AsmReadDr7 () | BIT10; // H/w sets bit 10, some simulators don't 159 if (!IsDrxEnabled (0, NewDr7) && (AsmReadDr0 () == 0 || AsmReadDr0 () == Signature)) { 160 // 161 // If user changed Dr3 (by setting HW bp in the above exception handler, 162 // we will not set Dr0 to 0 in GO/STEP handler because the break cause is not IMAGE_LOAD/_UNLOAD. 163 // 164 AsmWriteDr0 (Dr0); 165 } 166 if (!IsDrxEnabled (1, NewDr7) && (AsmReadDr1 () == (UINTN) ImageContext->PdbPointer)) { 167 AsmWriteDr1 (Dr1); 168 } 169 if (!IsDrxEnabled (2, NewDr7) && (AsmReadDr2 () == (UINTN) ImageContext)) { 170 AsmWriteDr2 (Dr2); 171 } 172 if (!IsDrxEnabled (3, NewDr7) && (AsmReadDr3 () == IO_PORT_BREAKPOINT_ADDRESS)) { 173 AsmWriteDr3 (Dr3); 174 } 175 if (LoadImageMethod == DEBUG_LOAD_IMAGE_METHOD_IO_HW_BREAKPOINT) { 176 if (AsmReadCr4 () == (Cr4 | BIT3)) { 177 AsmWriteCr4 (Cr4); 178 } 179 if (NewDr7 == 0x20000480) { 180 AsmWriteDr7 (Dr7); 181 } 182 } else if (LoadImageMethod == DEBUG_LOAD_IMAGE_METHOD_SOFT_INT3) { 183 if (NewDr7 == BIT10) { 184 AsmWriteDr7 (Dr7); 185 } 186 } 187 // 188 // Restore original IDT entry for INT1 if it was hooked. 189 // 190 if (IdtEntryHooked) { 191 RestoreIdtEntry1 (&IdtDescriptor, &OriginalIdtEntry); 192 } 193 // 194 // Restore the interrupt state 195 // 196 SetInterruptState (InterruptState); 197 } 198 199 /** 200 Performs additional actions after a PE/COFF image has been loaded and relocated. 201 202 @param ImageContext Pointer to the image context structure that describes the 203 PE/COFF image that has already been loaded and relocated. 204 205 **/ 206 VOID 207 EFIAPI 208 PeCoffLoaderRelocateImageExtraAction ( 209 IN OUT PE_COFF_LOADER_IMAGE_CONTEXT *ImageContext 210 ) 211 { 212 PeCoffLoaderExtraActionCommon (ImageContext, IMAGE_LOAD_SIGNATURE); 213 } 214 215 /** 216 Performs additional actions just before a PE/COFF image is unloaded. Any resources 217 that were allocated by PeCoffLoaderRelocateImageExtraAction() must be freed. 218 219 @param ImageContext Pointer to the image context structure that describes the 220 PE/COFF image that is being unloaded. 221 222 **/ 223 VOID 224 EFIAPI 225 PeCoffLoaderUnloadImageExtraAction ( 226 IN OUT PE_COFF_LOADER_IMAGE_CONTEXT *ImageContext 227 ) 228 { 229 PeCoffLoaderExtraActionCommon (ImageContext, IMAGE_UNLOAD_SIGNATURE); 230 } 231
