+/*
+ * This file is part of the Palacios Virtual Machine Monitor developed
+ * by the V3VEE Project with funding from the United States National
+ * Science Foundation and the Department of Energy.
+ *
+ * The V3VEE Project is a joint project between Northwestern University
+ * and the University of New Mexico. You can find out more at
+ * http://www.v3vee.org
+ *
+ * Copyright (c) 2008, Jack Lange <jarusl@cs.northwestern.edu>
+ * Copyright (c) 2008, The V3VEE Project <http://www.v3vee.org>
+ * All rights reserved.
+ *
+ * Author: Jack Lange <jarusl@cs.northwestern.edu>
+ *
+ * This is free software. You are permitted to use,
+ * redistribute, and modify it as specified in the file "V3VEE_LICENSE".
+ */
+
#include <palacios/vmm_mem.h>
#include <palacios/vmm.h>
#include <palacios/vmcb.h>
-#include <palacios/vmm_emulate.h>
+#include <palacios/vmm_decoder.h>
#include <palacios/vm_guest_mem.h>
#include <palacios/vmm_ctrl_regs.h>
+
/* Segmentation is a problem here...
*
* When we get a memory operand, presumably we use the default segment (which is?)
*/
+#ifndef DEBUG_CTRL_REGS
+#undef PrintDebug
+#define PrintDebug(fmt, args...)
+#endif
+
+
+// First Attempt = 494 lines
+// current = 106 lines
int handle_cr0_write(struct guest_info * info) {
- char instr[15];
-
-
- if (info->cpu_mode == REAL) {
- int index = 0;
- int ret;
+ uchar_t instr[15];
+ int ret;
+ struct x86_instr dec_instr;
- // The real rip address is actually a combination of the rip + CS base
+ if (info->mem_mode == PHYSICAL_MEM) {
ret = read_guest_pa_memory(info, get_addr_linear(info, info->rip, &(info->segments.cs)), 15, instr);
- if (ret != 15) {
- // I think we should inject a GPF into the guest
- PrintDebug("Could not read instruction (ret=%d)\n", ret);
- return -1;
- }
+ } else {
+ ret = read_guest_va_memory(info, get_addr_linear(info, info->rip, &(info->segments.cs)), 15, instr);
+ }
- while (is_prefix_byte(instr[index])) {
- index++;
+ /* The IFetch will already have faulted in the necessary bytes for the full instruction
+ if (ret != 15) {
+ // I think we should inject a GPF into the guest
+ PrintError("Could not read instruction (ret=%d)\n", ret);
+ return -1;
}
+ */
- if ((instr[index] == cr_access_byte) &&
- (instr[index + 1] == lmsw_byte) &&
- (MODRM_REG(instr[index + 2]) == lmsw_reg_byte)) {
-
- addr_t first_operand;
- addr_t second_operand;
- struct cr0_real *real_cr0;
- struct cr0_real *new_cr0;
- operand_type_t addr_type;
- char new_cr0_val = 0;
- // LMSW
- // decode mod/RM
- index += 2;
-
- real_cr0 = (struct cr0_real*)&(info->ctrl_regs.cr0);
-
- addr_type = decode_operands16(&(info->vm_regs), instr + index, &index, &first_operand, &second_operand, REG16);
-
-
- if (addr_type == REG_OPERAND) {
- new_cr0 = (struct cr0_real *)first_operand;
- } else if (addr_type == MEM_OPERAND) {
- addr_t host_addr;
-
- if (guest_pa_to_host_va(info, first_operand + (info->segments.ds.base << 4), &host_addr) == -1) {
- // gpf the guest
- return -1;
- }
-
- new_cr0 = (struct cr0_real *)host_addr;
- } else {
- // error... don't know what to do
- return -1;
- }
-
- if ((new_cr0->pe == 1) && (real_cr0->pe == 0)) {
- info->cpu_mode = PROTECTED;
- } else if ((new_cr0->pe == 0) && (real_cr0->pe == 1)) {
- info->cpu_mode = REAL;
- }
-
- new_cr0_val = *(char*)(new_cr0) & 0x0f;
-
-
- if (info->page_mode == SHADOW_PAGING) {
- struct cr0_real * shadow_cr0 = (struct cr0_real*)&(info->shdw_pg_state.guest_cr0);
-
- PrintDebug("Old CR0=%x, Old Shadow CR0=%x\n", *real_cr0, *shadow_cr0);
- /* struct cr0_real is only 4 bits wide,
- * so we can overwrite the real_cr0 without worrying about the shadow fields
- */
- *(char*)real_cr0 &= 0xf0;
- *(char*)real_cr0 |= new_cr0_val;
-
- *(char*)shadow_cr0 &= 0xf0;
- *(char*)shadow_cr0 |= new_cr0_val;
-
- PrintDebug("New CR0=%x, New Shadow CR0=%x\n", *real_cr0, *shadow_cr0);
- } else {
- PrintDebug("Old CR0=%x\n", *real_cr0);
- // for now we just pass through....
- *(char*)real_cr0 &= 0xf0;
- *(char*)real_cr0 |= new_cr0_val;
-
- PrintDebug("New CR0=%x\n", *real_cr0);
- }
+ if (v3_decode(info, (addr_t)instr, &dec_instr) == -1) {
+ PrintError("Could not decode instruction\n");
+ return -1;
+ }
- info->rip += index;
+ if (opcode_cmp(V3_OPCODE_LMSW, (const uchar_t *)(dec_instr.opcode)) == 0) {
+ struct cr0_real *real_cr0 = (struct cr0_real*)&(info->ctrl_regs.cr0);
+ struct cr0_real *new_cr0 = (struct cr0_real *)(dec_instr.src_operand.operand);
+ uchar_t new_cr0_val;
- } else if ((instr[index] == cr_access_byte) &&
- (instr[index + 1] == clts_byte)) {
- // CLTS
+ PrintDebug("LMSW\n");
+ new_cr0_val = (*(char*)(new_cr0)) & 0x0f;
+
+ PrintDebug("OperandVal = %x\n", new_cr0_val);
- } else if ((instr[index] == cr_access_byte) &&
- (instr[index + 1] = mov_to_cr_byte)) {
- addr_t first_operand;
- addr_t second_operand;
- struct cr0_32 *real_cr0;
- struct cr0_32 *new_cr0;
- operand_type_t addr_type;
-
+ PrintDebug("Old CR0=%x\n", *real_cr0);
+ *(uchar_t*)real_cr0 &= 0xf0;
+ *(uchar_t*)real_cr0 |= new_cr0_val;
+ PrintDebug("New CR0=%x\n", *real_cr0);
- index += 2;
-
- real_cr0 = (struct cr0_32*)&(info->ctrl_regs.cr0);
-
- addr_type = decode_operands16(&(info->vm_regs), instr + index, &index, &first_operand, &second_operand, REG32);
-
- if (addr_type != REG_OPERAND) {
- /* Mov to CR0 Can only be a 32 bit register */
- // FIX ME
- return -1;
- }
- new_cr0 = (struct cr0_32 *)first_operand;
-
- if (new_cr0->pe == 1) {
- PrintDebug("Entering Protected Mode\n");
- info->cpu_mode = PROTECTED;
- }
-
- if (new_cr0->pg == 1) {
- // GPF the guest??
- return -1;
- }
-
- if (info->page_mode == SHADOW_PAGING) {
- struct cr0_32 * shadow_cr0 = (struct cr0_32 *)&(info->shdw_pg_state.guest_cr0);
-
- PrintDebug("Old CR0=%x, Old Shadow CR0=%x\n", *real_cr0, *shadow_cr0);
- *real_cr0 = *new_cr0;
- real_cr0->pg = 1;
-
- *shadow_cr0 = *new_cr0;
-
- PrintDebug("New CR0=%x, New Shadow CR0=%x\n", *real_cr0, *shadow_cr0);
- } else {
- PrintDebug("Old CR0=%x\n", *real_cr0);
- *real_cr0 = *new_cr0;
- PrintDebug("New CR0=%x\n", *real_cr0);
- }
-
- info->rip += index;
-
- } else {
- PrintDebug("Unsupported Instruction\n");
- // unsupported instruction, UD the guest
- return -1;
- }
-
-
- } else if (info->cpu_mode == PROTECTED) {
- int index = 0;
- int ret;
-
- PrintDebug("Protected Mode write to CR0\n");
-
- // The real rip address is actually a combination of the rip + CS base
- ret = read_guest_pa_memory(info, get_addr_linear(info, info->rip, &(info->segments.cs)), 15, instr);
- if (ret != 15) {
- // I think we should inject a GPF into the guest
- PrintDebug("Could not read instruction (ret=%d)\n", ret);
- return -1;
- }
-
- while (is_prefix_byte(instr[index])) {
- index++;
+ if (info->shdw_pg_mode == SHADOW_PAGING) {
+ struct cr0_real * shadow_cr0 = (struct cr0_real*)&(info->shdw_pg_state.guest_cr0);
+
+ PrintDebug(" Old Shadow CR0=%x\n", *shadow_cr0);
+ *(uchar_t*)shadow_cr0 &= 0xf0;
+ *(uchar_t*)shadow_cr0 |= new_cr0_val;
+ PrintDebug("New Shadow CR0=%x\n", *shadow_cr0);
}
+ } else if (opcode_cmp(V3_OPCODE_MOV2CR, (const uchar_t *)(dec_instr.opcode)) == 0) {
+ PrintDebug("MOV2CR0\n");
- if ((instr[index] == cr_access_byte) &&
- (instr[index + 1] == mov_to_cr_byte)) {
-
- addr_t first_operand;
- addr_t second_operand;
- struct cr0_32 *real_cr0;
- struct cr0_32 *new_cr0;
- operand_type_t addr_type;
-
- index += 2;
-
- real_cr0 = (struct cr0_32*)&(info->ctrl_regs.cr0);
-
- addr_type = decode_operands32(&(info->vm_regs), instr + index, &index, &first_operand, &second_operand, REG32);
-
- if (addr_type != REG_OPERAND) {
- return -1;
- }
-
- new_cr0 = (struct cr0_32 *)first_operand;
+ if (info->cpu_mode == LONG) {
+ // 64 bit registers
+ } else {
+ // 32 bit registers
+ struct cr0_32 *real_cr0 = (struct cr0_32*)&(info->ctrl_regs.cr0);
+ struct cr0_32 *new_cr0= (struct cr0_32 *)(dec_instr.src_operand.operand);
+ PrintDebug("OperandVal = %x, length=%d\n", *new_cr0, dec_instr.src_operand.size);
- if (info->page_mode == SHADOW_PAGING) {
- struct cr0_32 * shadow_cr0 = (struct cr0_32 *)&(info->shdw_pg_state.guest_cr0);
- if (new_cr0->pg == 1){
- struct cr3_32 * shadow_cr3 = (struct cr3_32 *)&(info->shdw_pg_state.shadow_cr3);
+ PrintDebug("Old CR0=%x\n", *real_cr0);
+ *real_cr0 = *new_cr0;
+
- info->cpu_mode = PROTECTED_PG;
+ if (info->shdw_pg_mode == SHADOW_PAGING) {
+ struct cr0_32 * shadow_cr0 = (struct cr0_32 *)&(info->shdw_pg_state.guest_cr0);
- *shadow_cr0 = *new_cr0;
- *real_cr0 = *new_cr0;
-
- //
- // Activate Shadow Paging
- //
- PrintDebug("Turning on paging in the guest\n");
-
- info->ctrl_regs.cr3 = *(addr_t*)shadow_cr3;
+ PrintDebug("Old Shadow CR0=%x\n", *shadow_cr0);
+ real_cr0->et = 1;
+
+ *shadow_cr0 = *new_cr0;
+ shadow_cr0->et = 1;
+
+ if (get_mem_mode(info) == VIRTUAL_MEM) {
+ struct cr3_32 * shadow_cr3 = (struct cr3_32 *)&(info->shdw_pg_state.shadow_cr3);
+
+ info->ctrl_regs.cr3 = *(addr_t*)shadow_cr3;
+ } else {
+ info->ctrl_regs.cr3 = *(addr_t*)&(info->direct_map_pt);
+ real_cr0->pg = 1;
+ }
+
+ PrintDebug("New Shadow CR0=%x\n",*shadow_cr0);
+ }
+ PrintDebug("New CR0=%x\n", *real_cr0);
+ }
- } else if (new_cr0->pe == 0) {
- info->cpu_mode = REAL;
-
- *shadow_cr0 = *new_cr0;
- *real_cr0 = *new_cr0;
- real_cr0->pg = 1;
- }
-
-
- } else {
- *real_cr0 = *new_cr0;
- }
+ } else if (opcode_cmp(V3_OPCODE_CLTS, (const uchar_t *)(dec_instr.opcode)) == 0) {
+ // CLTS
+ struct cr0_32 *real_cr0 = (struct cr0_32*)&(info->ctrl_regs.cr0);
+
+ real_cr0->ts = 0;
- info->rip += index;
+ if (info->shdw_pg_mode == SHADOW_PAGING) {
+ struct cr0_32 * shadow_cr0 = (struct cr0_32 *)&(info->shdw_pg_state.guest_cr0);
+ shadow_cr0->ts = 0;
}
-
- } else {
- PrintDebug("Unknown Mode write to CR0\n");
+ } else {
+ PrintError("Unhandled opcode in handle_cr0_write\n");
return -1;
}
+
+ info->rip += dec_instr.instr_length;
+
return 0;
}
+// First attempt = 253 lines
+// current = 51 lines
int handle_cr0_read(struct guest_info * info) {
- char instr[15];
+ uchar_t instr[15];
+ int ret;
+ struct x86_instr dec_instr;
- if (info->cpu_mode == REAL) {
- int index = 0;
- int ret;
-
- // The real rip address is actually a combination of the rip + CS base
+ if (info->mem_mode == PHYSICAL_MEM) {
ret = read_guest_pa_memory(info, get_addr_linear(info, info->rip, &(info->segments.cs)), 15, instr);
- if (ret != 15) {
- // I think we should inject a GPF into the guest
- PrintDebug("Could not read Real Mode instruction (ret=%d)\n", ret);
- return -1;
- }
-
-
- while (is_prefix_byte(instr[index])) {
- index++;
- }
-
- if ((instr[index] == cr_access_byte) &&
- (instr[index + 1] == smsw_byte) &&
- (MODRM_REG(instr[index + 2]) == smsw_reg_byte)) {
-
- addr_t first_operand;
- addr_t second_operand;
- struct cr0_real *cr0;
- operand_type_t addr_type;
- char cr0_val = 0;
-
- index += 2;
-
- cr0 = (struct cr0_real*)&(info->ctrl_regs.cr0);
-
-
- addr_type = decode_operands16(&(info->vm_regs), instr + index, &index, &first_operand, &second_operand, REG16);
-
- if (addr_type == MEM_OPERAND) {
- addr_t host_addr;
-
- if (guest_pa_to_host_va(info, first_operand + (info->segments.ds.base << 4), &host_addr) == -1) {
- // gpf the guest
- PrintDebug("Could not convert guest physical address to host virtual address\n");
- return -1;
- }
-
- first_operand = host_addr;
- } else {
- // Register operand
- // Should be ok??
- }
-
- cr0_val = *(char*)cr0 & 0x0f;
-
- *(char *)first_operand &= 0xf0;
- *(char *)first_operand |= cr0_val;
-
- PrintDebug("index = %d, rip = %x\n", index, (ulong_t)(info->rip));
- info->rip += index;
- PrintDebug("new_rip = %x\n", (ulong_t)(info->rip));
- } else if ((instr[index] == cr_access_byte) &&
- (instr[index+1] == mov_from_cr_byte)) {
- /* Mov from CR0
- * This can only take a 32 bit register argument in anything less than 64 bit mode.
- */
- addr_t first_operand;
- addr_t second_operand;
- operand_type_t addr_type;
-
- struct cr0_32 * real_cr0 = (struct cr0_32 *)&(info->ctrl_regs.cr0);
+ } else {
+ ret = read_guest_va_memory(info, get_addr_linear(info, info->rip, &(info->segments.cs)), 15, instr);
+ }
- index += 2;
+ /* The IFetch will already have faulted in the necessary bytes for the full instruction
+ if (ret != 15) {
+ // I think we should inject a GPF into the guest
+ PrintError("Could not read instruction (ret=%d)\n", ret);
+ return -1;
+ }
+ */
- addr_type = decode_operands16(&(info->vm_regs), instr + index, &index, &first_operand, &second_operand, REG32);
-
- struct cr0_32 * virt_cr0 = (struct cr0_32 *)first_operand;
+ if (v3_decode(info, (addr_t)instr, &dec_instr) == -1) {
+ PrintError("Could not decode instruction\n");
+ return -1;
+ }
- if (addr_type != REG_OPERAND) {
- // invalid opcode to guest
- PrintDebug("Invalid operand type in mov from CR0\n");
- return -1;
- }
-
- if (info->page_mode == SHADOW_PAGING) {
- *virt_cr0 = *(struct cr0_32 *)&(info->shdw_pg_state.guest_cr0);
- } else {
- *virt_cr0 = *real_cr0;
- }
-
- info->rip += index;
+ if (opcode_cmp(V3_OPCODE_MOVCR2, (const uchar_t *)(dec_instr.opcode)) == 0) {
+ struct cr0_32 * virt_cr0 = (struct cr0_32 *)(dec_instr.dst_operand.operand);
+ struct cr0_32 * real_cr0 = (struct cr0_32 *)&(info->ctrl_regs.cr0);
+
+ PrintDebug("MOVCR2\n");
+ PrintDebug("CR0 at 0x%x\n", real_cr0);
+ if (info->shdw_pg_mode == SHADOW_PAGING) {
+ *virt_cr0 = *(struct cr0_32 *)&(info->shdw_pg_state.guest_cr0);
} else {
- PrintDebug("Unknown read instr from CR0\n");
- return -1;
- }
-
- } else if (info->cpu_mode == PROTECTED) {
- int index = 0;
- int ret;
-
- // The real rip address is actually a combination of the rip + CS base
- ret = read_guest_pa_memory(info, get_addr_linear(info, info->rip, &(info->segments.cs)), 15, instr);
- if (ret != 15) {
- // I think we should inject a GPF into the guest
- PrintDebug("Could not read Proteced mode instruction (ret=%d)\n", ret);
- return -1;
- }
-
- while (is_prefix_byte(instr[index])) {
- index++;
+ *virt_cr0 = *real_cr0;
}
+
+ PrintDebug("real CR0: %x\n", *(uint_t*)real_cr0);
+ PrintDebug("returned CR0: %x\n", *(uint_t*)virt_cr0);
+ } else if (opcode_cmp(V3_OPCODE_SMSW, (const uchar_t *)(dec_instr.opcode)) == 0) {
+ struct cr0_real *real_cr0= (struct cr0_real*)&(info->ctrl_regs.cr0);
+ struct cr0_real *virt_cr0 = (struct cr0_real *)(dec_instr.dst_operand.operand);
+ char cr0_val = *(char*)real_cr0 & 0x0f;
+
+ PrintDebug("SMSW\n");
+ PrintDebug("CR0 at 0x%x\n", real_cr0);
- if ((instr[index] == cr_access_byte) &&
- (instr[index+1] == mov_from_cr_byte)) {
- addr_t first_operand;
- addr_t second_operand;
- operand_type_t addr_type;
- struct cr0_32 * virt_cr0;
- struct cr0_32 * real_cr0 = (struct cr0_32 *)&(info->ctrl_regs.cr0);
-
- index += 2;
-
- addr_type = decode_operands32(&(info->vm_regs), instr + index, &index, &first_operand, &second_operand, REG32);
-
- if (addr_type != REG_OPERAND) {
- PrintDebug("Invalid operand type in mov from CR0\n");
- return -1;
- }
-
- virt_cr0 = (struct cr0_32 *)first_operand;
-
- if (info->page_mode == SHADOW_PAGING) {
- *virt_cr0 = *(struct cr0_32 *)&(info->shdw_pg_state.guest_cr0);
- } else {
- *virt_cr0 = *real_cr0;
- }
-
- info->rip += index;
-
- } else {
- PrintDebug("Unknown read instruction from CR0\n");
- return -1;
- }
-
+ *(char *)virt_cr0 &= 0xf0;
+ *(char *)virt_cr0 |= cr0_val;
+
} else {
- PrintDebug("Unknown mode read from CR0\n");
+ PrintError("Unhandled opcode in handle_cr0_read\n");
return -1;
}
+ info->rip += dec_instr.instr_length;
return 0;
}
-
+// First Attempt = 256 lines
+// current = 65 lines
int handle_cr3_write(struct guest_info * info) {
- if ((info->cpu_mode == PROTECTED) || (info->cpu_mode == PROTECTED_PG)) {
- int index = 0;
- int ret;
- char instr[15];
-
+ int ret;
+ uchar_t instr[15];
+ struct x86_instr dec_instr;
- /* Isn't the RIP a Guest Virtual Address???????? */
+ if (info->mem_mode == PHYSICAL_MEM) {
ret = read_guest_pa_memory(info, get_addr_linear(info, info->rip, &(info->segments.cs)), 15, instr);
- if (ret != 15) {
- PrintDebug("Could not read instruction (ret=%d)\n", ret);
- return -1;
- }
-
- while (is_prefix_byte(instr[index])) {
- index++;
- }
-
- if ((instr[index] == cr_access_byte) &&
- (instr[index + 1] == mov_to_cr_byte)) {
-
- addr_t first_operand;
- addr_t second_operand;
- struct cr3_32 * new_cr3;
- // struct cr3_32 * real_cr3;
- operand_type_t addr_type;
+ } else {
+ ret = read_guest_va_memory(info, get_addr_linear(info, info->rip, &(info->segments.cs)), 15, instr);
+ }
- index += 2;
+ /* The IFetch will already have faulted in the necessary bytes for the full instruction
+ if (ret != 15) {
+ // I think we should inject a GPF into the guest
+ PrintError("Could not read instruction (ret=%d)\n", ret);
+ return -1;
+ }
+ */
- addr_type = decode_operands32(&(info->vm_regs), instr + index, &index, &first_operand, &second_operand, REG32);
+ if (v3_decode(info, (addr_t)instr, &dec_instr) == -1) {
+ PrintError("Could not decode instruction\n");
+ return -1;
+ }
- if (addr_type != REG_OPERAND) {
- /* Mov to CR3 can only be a 32 bit register */
- return -1;
- }
+ if (opcode_cmp(V3_OPCODE_MOV2CR, (const uchar_t *)(dec_instr.opcode)) == 0) {
- new_cr3 = (struct cr3_32 *)first_operand;
+ PrintDebug("MOV2CR3\n");
- if (info->page_mode == SHADOW_PAGING) {
- addr_t shadow_pt;
- struct cr3_32 * shadow_cr3 = (struct cr3_32 *)&(info->shdw_pg_state.shadow_cr3);
- struct cr3_32 * guest_cr3 = (struct cr3_32 *)&(info->shdw_pg_state.guest_cr3);
+ PrintDebug("CR3 at 0x%x\n", &(info->ctrl_regs.cr3));
+ if (info->shdw_pg_mode == SHADOW_PAGING) {
+ struct cr3_32 * new_cr3 = (struct cr3_32 *)(dec_instr.src_operand.operand);
+ struct cr3_32 * guest_cr3 = (struct cr3_32 *)&(info->shdw_pg_state.guest_cr3);
+ struct cr3_32 * shadow_cr3 = (struct cr3_32 *)&(info->shdw_pg_state.shadow_cr3);
+ int cached = 0;
+
- *guest_cr3 = *new_cr3;
+ PrintDebug("Old Shadow CR3=%x; Old Guest CR3=%x\n",
+ *(uint_t*)shadow_cr3, *(uint_t*)guest_cr3);
+
- // Something like this
- shadow_pt = create_new_shadow_pt32(info);
- //shadow_pt = setup_shadow_pt32(info, CR3_TO_PDE32(*(addr_t *)new_cr3));
+ cached = cache_page_tables32(info, CR3_TO_PDE32(*(addr_t *)new_cr3));
- /* Copy Various flags */
- *shadow_cr3 = *new_cr3;
+ if (cached == -1) {
+ PrintError("CR3 Cache failed\n");
+ return -1;
+ } else if (cached == 0) {
+ addr_t shadow_pt;
- shadow_cr3->pdt_base_addr = PD32_BASE_ADDR(shadow_pt);
-
- if (info->cpu_mode == PROTECTED_PG) {
- // If we aren't in paged mode then we have to preserve the identity mapped CR3
- info->ctrl_regs.cr3 = *(addr_t*)shadow_cr3;
- }
+ PrintDebug("New CR3 is different - flushing shadow page table\n");
+
+ delete_page_tables_pde32((pde32_t *)CR3_TO_PDE32(*(uint_t*)shadow_cr3));
+
+ shadow_pt = create_new_shadow_pt32();
+
+ shadow_cr3->pdt_base_addr = PD32_BASE_ADDR(shadow_pt);
+ } else {
+ PrintDebug("Reusing cached shadow Page table\n");
}
+
+ shadow_cr3->pwt = new_cr3->pwt;
+ shadow_cr3->pcd = new_cr3->pcd;
+
+ // What the hell...
+ *guest_cr3 = *new_cr3;
+
+ PrintDebug("New Shadow CR3=%x; New Guest CR3=%x\n",
+ *(uint_t*)shadow_cr3, *(uint_t*)guest_cr3);
- info->rip += index;
-
- } else {
- PrintDebug("Unknown Instruction\n");
- return -1;
+ if (info->mem_mode == VIRTUAL_MEM) {
+ // If we aren't in paged mode then we have to preserve the identity mapped CR3
+ info->ctrl_regs.cr3 = *(addr_t*)shadow_cr3;
+ }
}
} else {
- PrintDebug("Invalid operating Mode\n");
+ PrintError("Unhandled opcode in handle_cr3_write\n");
return -1;
}
+ info->rip += dec_instr.instr_length;
+
return 0;
}
-
+// first attempt = 156 lines
+// current = 36 lines
int handle_cr3_read(struct guest_info * info) {
- if ((info->cpu_mode == PROTECTED) || (info->cpu_mode == PROTECTED_PG)) {
- int index = 0;
- int ret;
- char instr[15];
+ uchar_t instr[15];
+ int ret;
+ struct x86_instr dec_instr;
+ if (info->mem_mode == PHYSICAL_MEM) {
ret = read_guest_pa_memory(info, get_addr_linear(info, info->rip, &(info->segments.cs)), 15, instr);
- if (ret != 15) {
- PrintDebug("Could not read instruction (ret=%d)\n", ret);
- return -1;
- }
-
- while (is_prefix_byte(instr[index])) {
- index++;
- }
-
- if ((instr[index] == cr_access_byte) &&
- (instr[index + 1] == mov_from_cr_byte)) {
- addr_t first_operand;
- addr_t second_operand;
- struct cr3_32 * virt_cr3;
- struct cr3_32 * real_cr3 = (struct cr3_32 *)&(info->ctrl_regs.cr3);
- operand_type_t addr_type;
+ } else {
+ ret = read_guest_va_memory(info, get_addr_linear(info, info->rip, &(info->segments.cs)), 15, instr);
+ }
- index += 2;
+ /* The IFetch will already have faulted in the necessary bytes for the full instruction
+ if (ret != 15) {
+ // I think we should inject a GPF into the guest
+ PrintError("Could not read instruction (ret=%d)\n", ret);
+ return -1;
+ }
+ */
- addr_type = decode_operands32(&(info->vm_regs), instr + index, &index, &first_operand, &second_operand, REG32);
+ if (v3_decode(info, (addr_t)instr, &dec_instr) == -1) {
+ PrintError("Could not decode instruction\n");
+ return -1;
+ }
- if (addr_type != REG_OPERAND) {
- /* Mov to CR3 can only be a 32 bit register */
- return -1;
- }
+ if (opcode_cmp(V3_OPCODE_MOVCR2, (const uchar_t *)(dec_instr.opcode)) == 0) {
+ PrintDebug("MOVCR32\n");
+ struct cr3_32 * virt_cr3 = (struct cr3_32 *)(dec_instr.dst_operand.operand);
- virt_cr3 = (struct cr3_32 *)first_operand;
+ PrintDebug("CR3 at 0x%x\n", &(info->ctrl_regs.cr3));
- if (info->page_mode == SHADOW_PAGING) {
- *virt_cr3 = *(struct cr3_32 *)&(info->shdw_pg_state.guest_cr3);
- } else {
- *virt_cr3 = *real_cr3;
- }
-
- info->rip += index;
+ if (info->shdw_pg_mode == SHADOW_PAGING) {
+ *virt_cr3 = *(struct cr3_32 *)&(info->shdw_pg_state.guest_cr3);
} else {
- PrintDebug("Unknown Instruction\n");
- return -1;
+ *virt_cr3 = *(struct cr3_32 *)&(info->ctrl_regs.cr3);
}
} else {
- PrintDebug("Invalid operating Mode\n");
+ PrintError("Unhandled opcode in handle_cr3_read\n");
return -1;
}
+ info->rip += dec_instr.instr_length;
+
return 0;
}
