- #include <palacios/vmm_mem.h>
+/*
+ * 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_decoder.h>
-extern void SerialMemDump(unsigned char *start, int n);
-
-
/* Segmentation is a problem here...
*
* When we get a memory operand, presumably we use the default segment (which is?)
*/
-int handle_cr0_write(struct guest_info * info) {
- char instr[15];
-
-
- switch (info->cpu_mode) {
- case REAL:
- {
- int index = 0;
- int ret;
-
- PrintDebug("Real Mode write to CR0 at linear guest pa 0x%x\n",get_addr_linear(info,info->rip,&(info->segments.cs)));
+#ifndef DEBUG_CTRL_REGS
+#undef PrintDebug
+#define PrintDebug(fmt, args...)
+#endif
- //PrintV3Segments(info);
- // 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;
- }
+// First Attempt = 494 lines
+// current = 106 lines
+int handle_cr0_write(struct guest_info * info) {
+ char instr[15];
+ int ret;
+ struct x86_instr dec_instr;
- while (is_prefix_byte(instr[index])) {
- switch(instr[index]) {
- case PREFIX_CS_OVERRIDE:
- case PREFIX_SS_OVERRIDE:
- case PREFIX_DS_OVERRIDE:
- case PREFIX_ES_OVERRIDE:
- case PREFIX_FS_OVERRIDE:
- case PREFIX_GS_OVERRIDE:
- PrintDebug("Segment Override!!\n");
- return -1;
- break;
- default:
- break;
- }
- index++;
- }
+ if (info->mem_mode == PHYSICAL_MEM) {
+ ret = read_guest_pa_memory(info, get_addr_linear(info, info->rip, &(info->segments.cs)), 15, instr);
+ } else {
+ ret = read_guest_va_memory(info, get_addr_linear(info, info->rip, &(info->segments.cs)), 15, instr);
+ }
- 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);
+ /* 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, REG16);
+ if (v3_decode(info, (addr_t)instr, &dec_instr) == -1) {
+ PrintError("Could not decode instruction\n");
+ return -1;
+ }
- if (addr_type == REG_OPERAND) {
- new_cr0 = (struct cr0_real *)first_operand;
- } else if (addr_type == MEM_OPERAND) {
- addr_t host_addr;
+ 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;
- if (guest_pa_to_host_va(info, first_operand + (info->segments.ds.base << 4), &host_addr) == -1) {
- // gpf the guest
- return -1;
- }
+ PrintDebug("LMSW\n");
- new_cr0 = (struct cr0_real *)host_addr;
- } else {
+ new_cr0_val = (*(char*)(new_cr0)) & 0x0f;
+
+ PrintDebug("OperandVal = %x\n", new_cr0_val);
- // 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;
- }
+ 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);
- new_cr0_val = (*(char*)(new_cr0)) & 0x0f;
-
-
- if (info->shdw_pg_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);
- }
-
- info->rip += index;
-
- } else if ((instr[index] == cr_access_byte) &&
- (instr[index + 1] == clts_byte)) {
- // CLTS
- PrintDebug("CLTS unhandled in CR0 write\n");
- return -1;
-
- } 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;
-
+ if (info->shdw_pg_mode == SHADOW_PAGING) {
+ struct cr0_real * shadow_cr0 = (struct cr0_real*)&(info->shdw_pg_state.guest_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) {
- PrintDebug("Moving to CR0 from non-register operand in CR0 write\n");
- /* 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->pe == 0) {
- PrintDebug("Entering Real Mode\n");
- info->cpu_mode = REAL;
- }
-
-
-
- if ((new_cr0->pg == 1) && (new_cr0->pe == 1)) {
- PrintDebug("Paging is already turned on in switch to protected mode in CR0 write\n");
-
- // Actually This appears to be Ok.
- // Why shouldn't windows be allowed to switch to real mode whenever it wants to modify its page tables?
-
- info->mem_mode = VIRTUAL_MEM;
-
- // GPF the guest??
- // return -1;
- } else if ((new_cr0->pg == 1) && (new_cr0->pe == 0)) {
- PrintDebug("Will the madness Never End??\n");
- return -1;
- }
-
-
- if (info->shdw_pg_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;
- real_cr0->et = 1;
-
- *shadow_cr0 = *new_cr0;
- shadow_cr0->et = 1;
-
- // Setup the page tables...???
- 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*)&(info->shdw_pg_state.shadow_cr3);
- }
-
- 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;
- }
+ 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");
- }
- break;
-
- case PROTECTED:
- {
+ 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);
- int index = 0;
- int ret;
+ PrintDebug("OperandVal = %x, length=%d\n", *new_cr0, dec_instr.src_operand.size);
- PrintDebug("Protected %s Mode write to CR0 at guest %s linear rip 0x%x\n",
- info->mem_mode == VIRTUAL_MEM ? "Paged" : "",
- info->mem_mode == VIRTUAL_MEM ? "virtual" : "",
- get_addr_linear(info, info->rip, &(info->segments.cs)));
- // OK, now we will read the instruction
- // The only difference between PROTECTED and PROTECTED_PG is whether we read
- // from guest_pa or guest_va
- if (info->mem_mode == PHYSICAL_MEM) {
- // 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);
- } else {
- ret = read_guest_va_memory(info, get_addr_linear(info, info->rip, &(info->segments.cs)), 15, instr);
- }
+ PrintDebug("Old CR0=%x\n", *real_cr0);
+ *real_cr0 = *new_cr0;
- 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])) {
- switch(instr[index]) {
- case PREFIX_CS_OVERRIDE:
- case PREFIX_SS_OVERRIDE:
- case PREFIX_DS_OVERRIDE:
- case PREFIX_ES_OVERRIDE:
- case PREFIX_FS_OVERRIDE:
- case PREFIX_GS_OVERRIDE:
- PrintDebug("Segment Override!!\n");
- return -1;
- break;
- default:
- break;
- }
- index++;
- }
-
- /*
- while (is_prefix_byte(instr[index])) {
- index++;
- }
- */
-
- struct cr0_32 * shadow_cr0 = (struct cr0_32 *)&(info->shdw_pg_state.guest_cr0);
-
- struct cr0_32 * real_cr0 = (struct cr0_32*)&(info->ctrl_regs.cr0);
-
- if ((instr[index] == cr_access_byte) &&
- (instr[index + 1] == mov_to_cr_byte)) {
-
- // MOV to CR0
-
- addr_t first_operand;
- addr_t second_operand;
- struct cr0_32 *new_cr0;
- operand_type_t addr_type;
-
- index += 2;
-
- /*
- PrintDebug("MovToCR0 instr:\n");
- PrintTraceMemDump(instr, 15);
- PrintDebug("EAX=%x\n", *(uint_t*)&(info->vm_regs.rax));
- */
- addr_type = decode_operands32(&(info->vm_regs), instr + index, &index, &first_operand, &second_operand, REG32);
-
- if (addr_type != REG_OPERAND) {
- PrintDebug("Non-register operand in write to CR0\n");
- return -1;
- }
-
- new_cr0 = (struct cr0_32 *)first_operand;
-
- //PrintDebug("first operand=%x\n", *(uint_t *)first_operand);
-
- if (info->shdw_pg_mode == SHADOW_PAGING) {
- struct cr0_32 * shadow_cr0 = (struct cr0_32 *)&(info->shdw_pg_state.guest_cr0);
-
- if (new_cr0->pg == 1){
- // This should be new_cr0->pg && !(old_cr->pg), right?
- // and then a case for turning paging off?
-
- struct cr3_32 * shadow_cr3 = (struct cr3_32 *)&(info->shdw_pg_state.shadow_cr3);
-
- info->mem_mode = VIRTUAL_MEM;
+ 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;
- shadow_cr0->et = 1;
- real_cr0->et = 1;
-
- //
- // 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);
-
- } else if (new_cr0->pe == 0) {
- info->cpu_mode = REAL;
- info->mem_mode = PHYSICAL_MEM;
- PrintDebug("Entering Real Mode\n");
-
- //PrintV3CtrlRegs(info);
- // reinstate the identity mapped paged tables
- // But keep the shadow tables around to handle TLB issues.... UGH...
- //info->shdw_pg_state.shadow_cr3 &= 0x00000fff;
- //info->shdw_pg_state.shadow_cr3 |= ((addr_t)create_passthrough_pde32_pts(info) & ~0xfff);
-
- //info->ctrl_regs.cr3 = info->shdw_pg_state.shadow_cr3;
+ 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);
-
- *shadow_cr0 = *new_cr0;
- *real_cr0 = *new_cr0;
real_cr0->pg = 1;
- shadow_cr0->et = 1;
- real_cr0->et = 1;
-
- //PrintV3CtrlRegs(info);
-
- }
-
-
- } else {
- if (new_cr0->pg == 1) {
- info->mem_mode = VIRTUAL_MEM;
- } else if (new_cr0->pg == 0) {
- info->cpu_mode = REAL;
- info->mem_mode = PHYSICAL_MEM;
}
+
+ PrintDebug("New Shadow CR0=%x\n",*shadow_cr0);
+ }
+ PrintDebug("New CR0=%x\n", *real_cr0);
+ }
- *real_cr0 = *new_cr0;
- }
-
- info->rip += index;
- } else 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;
-
- 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;
- // check segment descriptors....
-
- /* TODO, TODO, TODO: Lookup segment overrides */
- struct v3_segment *lmsw_segment = &(info->segments.ds);
-
- if (info->mem_mode == PHYSICAL_MEM) {
- if (guest_pa_to_host_va(info, get_addr_linear(info, first_operand, lmsw_segment), &host_addr) == -1) {
- return -1;
- }
- } else {
- if (guest_va_to_host_va(info, get_addr_linear(info, first_operand, lmsw_segment), &host_addr) == -1) {
- return -1;
- }
- }
-
- new_cr0 = (struct cr0_real *)host_addr;
- } else {
- return -1;
- }
-
-
- if (new_cr0->pe == 0) {
- // According to the intel manual this it is illegal to use
- // lmsw to turn _off_ Protected mode
- PrintDebug("Cannot switch to real mode with LMSW, unclear what to do\n");
- return -1;
- }
-
- new_cr0_val = (*(char *)(new_cr0)) & 0x0f;
-
-
- if (info->shdw_pg_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);
- }
-
- info->rip += index;
-
-
- } else if ((instr[index] == 0x0f) &&
- (instr[index + 1] == 0x06)) {
- // CLTS instruction
- PrintDebug("CLTS instruction - clearing TS flag of real and shadow CR0\n");
- shadow_cr0->ts = 0;
- real_cr0->ts = 0;
+ } 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);
- index+=2;
-
- info->rip+=index;
+ real_cr0->ts = 0;
- } else {
- PrintDebug("Unkown instruction: \n");
- SerialMemDump(instr,15);
- return -1;
- }
+ 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;
}
- break;
-
- case PROTECTED_PAE:
- PrintDebug("Protected PAE Mode write to CR0 is UNIMPLEMENTED\n");
- return -1;
-
- case LONG:
- PrintDebug("Protected Long Mode write to CR0 is UNIMPLEMENTED\n");
+ } else {
+ PrintError("Unhandled opcode in handle_cr0_write\n");
return -1;
-
- default:
- {
- PrintDebug("Unknown Mode write to CR0 (info->cpu_mode=0x%x\n)",info->cpu_mode);
- return -1;
- }
- break;
-
}
+ 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];
+ int ret;
+ struct x86_instr dec_instr;
- switch (info->cpu_mode) {
-
- case REAL:
- {
-
- int index = 0;
- int ret;
-
- PrintDebug("Real Mode read from CR0 at linear guest pa 0x%x\n",get_addr_linear(info,info->rip,&(info->segments.cs)));
- //PrintV3Segments(info);
-
- // 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 Real Mode instruction (ret=%d)\n", ret);
- return -1;
- }
-
-
- while (is_prefix_byte(instr[index])) {
- switch(instr[index]) {
- case PREFIX_CS_OVERRIDE:
- case PREFIX_SS_OVERRIDE:
- case PREFIX_DS_OVERRIDE:
- case PREFIX_ES_OVERRIDE:
- case PREFIX_FS_OVERRIDE:
- case PREFIX_GS_OVERRIDE:
- PrintDebug("Segment Override!!\n");
- return -1;
- break;
- default:
- break;
- }
- index++;
- }
-
- /*
- 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)) {
-
- // SMSW (store machine status word)
-
- 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));
- // success
-
- } 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);
+ if (info->mem_mode == PHYSICAL_MEM) {
+ ret = read_guest_pa_memory(info, get_addr_linear(info, info->rip, &(info->segments.cs)), 15, instr);
+ } 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->shdw_pg_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 instr from CR0\n");
- return -1;
- }
-
- }
-
- break;
-
- case PROTECTED:
- {
+ 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);
- int index = 0;
- int ret;
-
- PrintDebug("Protected %s Mode read from CR0 at guest %s linear rip 0x%x\n",
- info->mem_mode == VIRTUAL_MEM ? "Paged" : "",
- info->mem_mode == VIRTUAL_MEM ? "virtual" : "",
- get_addr_linear(info, info->rip, &(info->segments.cs)));
-
- // We need to read the instruction, which is at CS:IP, but that
- // linear address is guest physical without PG and guest virtual with PG
- if (info->cpu_mode == PHYSICAL_MEM) {
- // 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);
- } else {
- // The real rip address is actually a combination of the rip + CS base
- ret = read_guest_va_memory(info, get_addr_linear(info, info->rip, &(info->segments.cs)), 15, instr);
- }
-
+ PrintDebug("MOVCR2\n");
+ PrintDebug("CR0 at 0x%x\n", real_cr0);
- /*
- PrintDebug("Instr (15 bytes) at %x:\n", instr);
- PrintTraceMemDump((char*)instr, 15);
- */
-
- if (ret != 15) {
- // I think we should inject a GPF into the guest
- PrintDebug("Could not read Protected %s mode instruction (ret=%d)\n",
- info->cpu_mode == VIRTUAL_MEM ? "Paged" : "", ret);
- return -1;
- }
-
-
- while (is_prefix_byte(instr[index])) {
- switch(instr[index]) {
- case PREFIX_CS_OVERRIDE:
- case PREFIX_SS_OVERRIDE:
- case PREFIX_DS_OVERRIDE:
- case PREFIX_ES_OVERRIDE:
- case PREFIX_FS_OVERRIDE:
- case PREFIX_GS_OVERRIDE:
- PrintDebug("Segment Override!!\n");
- return -1;
- break;
- default:
- break;
- }
- index++;
- }
-
-
- /*
- while (is_prefix_byte(instr[index])) {
- index++;
- }
- */
-
- if ((instr[index] == cr_access_byte) &&
- (instr[index+1] == mov_from_cr_byte)) {
-
- // MOV from CR0 to register
-
- 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->shdw_pg_mode == SHADOW_PAGING) {
- *virt_cr0 = *(struct cr0_32 *)&(info->shdw_pg_state.guest_cr0);
-
- if (info->mem_mode == PHYSICAL_MEM) {
- virt_cr0->pg = 0; // clear the pg bit because guest doesn't think it's on
- }
-
- } else {
- *virt_cr0 = *real_cr0;
- }
-
- PrintDebug("real CR0: %x\n", *(uint_t*)real_cr0);
- PrintDebug("returned CR0: %x\n", *(uint_t*)virt_cr0);
-
- info->rip += index;
-
- } else {
- PrintDebug("Unknown read instruction from CR0\n");
- return -1;
- }
+ if (info->shdw_pg_mode == SHADOW_PAGING) {
+ *virt_cr0 = *(struct cr0_32 *)&(info->shdw_pg_state.guest_cr0);
+ } else {
+ *virt_cr0 = *real_cr0;
}
- break;
+
+ 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");
- case PROTECTED_PAE:
- PrintDebug("Protected PAE Mode read to CR0 is UNIMPLEMENTED\n");
- return -1;
+ PrintDebug("CR0 at 0x%x\n", real_cr0);
- case LONG:
- PrintDebug("Protected Long Mode read to CR0 is UNIMPLEMENTED\n");
+ *(char *)virt_cr0 &= 0xf0;
+ *(char *)virt_cr0 |= cr0_val;
+
+ } else {
+ PrintError("Unhandled opcode in handle_cr0_read\n");
return -1;
-
-
- default:
- {
- PrintDebug("Unknown Mode read from CR0 (info->cpu_mode=0x%x)\n",info->cpu_mode);
- return -1;
- }
- break;
}
+ 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 == REAL) {
- // WHAT THE HELL DOES THIS EVEN MEAN?????
-
- int index = 0;
- int ret;
- char instr[15];
-
- PrintDebug("Real Mode Write to CR3.\n");
- // We need to read the instruction, which is at CS:IP, but that
- // linear address is guest physical without PG and guest virtual with PG
+ int ret;
+ char instr[15];
+ 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);
+ } else {
+ ret = read_guest_va_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])) {
- switch(instr[index]) {
- case PREFIX_CS_OVERRIDE:
- case PREFIX_SS_OVERRIDE:
- case PREFIX_DS_OVERRIDE:
- case PREFIX_ES_OVERRIDE:
- case PREFIX_FS_OVERRIDE:
- case PREFIX_GS_OVERRIDE:
- PrintDebug("Segment Override!!\n");
- return -1;
- break;
- default:
- break;
- }
- 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;
-
- index += 2;
-
- addr_type = decode_operands16(&(info->vm_regs), instr + index, &index, &first_operand, &second_operand, REG32);
-
- if (addr_type != REG_OPERAND) {
- /* Mov to CR3 can only be a 32 bit register */
- return -1;
- }
-
- new_cr3 = (struct cr3_32 *)first_operand;
-
- if (info->shdw_pg_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);
-
- /*
-
- if (CR3_TO_PDE32(*(uint_t*)shadow_cr3) != 0) {
- PrintDebug("Shadow Page Table\n");
- PrintDebugPageTables((pde32_t *)CR3_TO_PDE32(*(uint_t*)shadow_cr3));
- }
- */
-
- /* Delete the current Page Tables */
- delete_page_tables_pde32((pde32_t *)CR3_TO_PDE32(*(uint_t*)shadow_cr3));
-
- PrintDebug("Old Shadow CR3=%x; Old Guest CR3=%x\n",
- *(uint_t*)shadow_cr3, *(uint_t*)guest_cr3);
-
-
- *guest_cr3 = *new_cr3;
-
-
-
- // Something like this
- shadow_pt = create_new_shadow_pt32(info);
- //shadow_pt = setup_shadow_pt32(info, CR3_TO_PDE32(*(addr_t *)new_cr3));
-
- /* Copy Various flags */
- *shadow_cr3 = *new_cr3;
-
- /*
- {
- addr_t tmp_addr;
- guest_pa_to_host_va(info, ((*(uint_t*)guest_cr3) & 0xfffff000), &tmp_addr);
- PrintDebug("Guest PD\n");
- PrintPD32((pde32_t *)tmp_addr);
-
- }
- */
-
-
- shadow_cr3->pdt_base_addr = PD32_BASE_ADDR(shadow_pt);
-
- 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");
- SerialMemDump(instr,15);
- return -1;
- }
-
-
-
- } else if (info->cpu_mode == PROTECTED) {
- int index = 0;
- int ret;
- char instr[15];
-
- PrintDebug("Protected %s mode write to CR3 at %s 0x%x\n",
- info->cpu_mode==PROTECTED ? "" : "Paged",
- info->cpu_mode==PROTECTED ? "guest physical" : "guest virtual",
- get_addr_linear(info,info->rip,&(info->segments.cs)));
+ /* 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;
+ }
+ */
- // We need to read the instruction, which is at CS:IP, but that
- // linear address is guest physical without PG and guest virtual with PG
- if (info->mem_mode == PHYSICAL_MEM) {
- // The real rip address is actually a combination of the rip + CS base
- //PrintDebug("Writing Guest CR3 Write (Physical Address)\n");
- ret = read_guest_pa_memory(info, get_addr_linear(info, info->rip, &(info->segments.cs)), 15, instr);
- } else {
- //PrintDebug("Writing Guest CR3 Write (Virtual Address)\n");
- // The real rip address is actually a combination of the rip + CS base
- ret = read_guest_va_memory(info, get_addr_linear(info, info->rip, &(info->segments.cs)), 15, instr);
- }
+ if (v3_decode(info, (addr_t)instr, &dec_instr) == -1) {
+ PrintError("Could not decode instruction\n");
+ return -1;
+ }
- if (ret != 15) {
- PrintDebug("Could not read instruction (ret=%d)\n", ret);
- return -1;
- }
+ if (opcode_cmp(V3_OPCODE_MOV2CR, (const uchar_t *)(dec_instr.opcode)) == 0) {
- while (is_prefix_byte(instr[index])) {
- switch(instr[index]) {
- case PREFIX_CS_OVERRIDE:
- case PREFIX_SS_OVERRIDE:
- case PREFIX_DS_OVERRIDE:
- case PREFIX_ES_OVERRIDE:
- case PREFIX_FS_OVERRIDE:
- case PREFIX_GS_OVERRIDE:
- PrintDebug("Segment Override!!\n");
- return -1;
- break;
- default:
- break;
- }
- index++;
- }
-
- /*
- while (is_prefix_byte(instr[index])) {
- index++;
- }
- */
+ PrintDebug("MOV2CR3\n");
- if ((instr[index] == cr_access_byte) &&
- (instr[index + 1] == mov_to_cr_byte)) {
+ PrintDebug("CR3 at 0x%x\n", &(info->ctrl_regs.cr3));
- addr_t first_operand;
- addr_t second_operand;
- struct cr3_32 * new_cr3;
- // struct cr3_32 * real_cr3;
- operand_type_t addr_type;
+ 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;
+
- index += 2;
+ PrintDebug("Old Shadow CR3=%x; Old Guest CR3=%x\n",
+ *(uint_t*)shadow_cr3, *(uint_t*)guest_cr3);
+
- addr_type = decode_operands32(&(info->vm_regs), instr + index, &index, &first_operand, &second_operand, REG32);
+ cached = cache_page_tables32(info, CR3_TO_PDE32(*(addr_t *)new_cr3));
- if (addr_type != REG_OPERAND) {
- /* Mov to CR3 can only be a 32 bit register */
+ if (cached == -1) {
+ PrintError("CR3 Cache failed\n");
return -1;
- }
-
- new_cr3 = (struct cr3_32 *)first_operand;
-
- if (info->shdw_pg_mode == SHADOW_PAGING) {
+ } else if (cached == 0) {
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);
-
-
- /*
- if (CR3_TO_PDE32(*(uint_t*)shadow_cr3) != 0) {
- PrintDebug("Shadow Page Table\n");
- PrintDebugPageTables((pde32_t *)CR3_TO_PDE32(*(uint_t*)shadow_cr3));
- }
- */
-
- /* Delete the current Page Tables */
+
+ PrintDebug("New CR3 is different - flushing shadow page table\n");
+
delete_page_tables_pde32((pde32_t *)CR3_TO_PDE32(*(uint_t*)shadow_cr3));
-
- PrintDebug("Old Shadow CR3=%x; Old Guest CR3=%x\n",
- *(uint_t*)shadow_cr3, *(uint_t*)guest_cr3);
-
-
- *guest_cr3 = *new_cr3;
-
-
-
- // Something like this
- shadow_pt = create_new_shadow_pt32(info);
- //shadow_pt = setup_shadow_pt32(info, CR3_TO_PDE32(*(addr_t *)new_cr3));
-
- /* Copy Various flags */
- *shadow_cr3 = *new_cr3;
-
- /*
- {
- addr_t tmp_addr;
- guest_pa_to_host_va(info, ((*(uint_t*)guest_cr3) & 0xfffff000), &tmp_addr);
- PrintDebug("Guest PD\n");
- PrintPD32((pde32_t *)tmp_addr);
-
- }
- */
-
- shadow_cr3->pdt_base_addr = PD32_BASE_ADDR(shadow_pt);
-
- PrintDebug("New Shadow CR3=%x; New Guest CR3=%x\n",
- *(uint_t*)shadow_cr3, *(uint_t*)guest_cr3);
-
-
-
- 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;
- }
+ 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");
- SerialMemDump(instr,15);
- 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 (0x%x)\n", info->cpu_mode);
+ 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) {
+ char instr[15];
+ int ret;
+ struct x86_instr dec_instr;
- if (info->cpu_mode == REAL) {
- char instr[15];
- int ret;
- int index = 0;
- addr_t linear_addr = 0;
-
- linear_addr = get_addr_linear(info, info->rip, &(info->segments.cs));
-
-
- //PrintDebug("RIP Linear: %x\n", linear_addr);
- //PrintV3Segments(info);
-
- ret = read_guest_pa_memory(info, linear_addr, 15, instr);
-
- if (ret != 15) {
- PrintDebug("Could not read instruction (ret=%d)\n", ret);
- return -1;
- }
-
- while (is_prefix_byte(instr[index])) {
- switch(instr[index]) {
- case PREFIX_CS_OVERRIDE:
- case PREFIX_SS_OVERRIDE:
- case PREFIX_DS_OVERRIDE:
- case PREFIX_ES_OVERRIDE:
- case PREFIX_FS_OVERRIDE:
- case PREFIX_GS_OVERRIDE:
- PrintDebug("Segment Override!!\n");
- return -1;
- break;
- default:
- break;
- }
- 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;
-
- index += 2;
-
- addr_type = decode_operands16(&(info->vm_regs), instr + index, &index, &first_operand, &second_operand, REG32);
-
- if (addr_type != REG_OPERAND) {
- /* Mov to CR3 can only be a 32 bit register */
- return -1;
- }
-
- virt_cr3 = (struct cr3_32 *)first_operand;
-
- if (info->shdw_pg_mode == SHADOW_PAGING) {
- *virt_cr3 = *(struct cr3_32 *)&(info->shdw_pg_state.guest_cr3);
- } else {
- *virt_cr3 = *real_cr3;
- }
-
- info->rip += index;
- } else {
- PrintDebug("Unknown Instruction\n");
- SerialMemDump(instr,15);
- return -1;
- }
-
-
- return 0;
- } else if (info->cpu_mode == PROTECTED) {
-
- int index = 0;
- int ret;
- char instr[15];
-
-
- // We need to read the instruction, which is at CS:IP, but that
- // linear address is guest physical without PG and guest virtual with PG
- if (info->cpu_mode == PHYSICAL_MEM) {
- // 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);
- } else {
- // The real rip address is actually a combination of the rip + CS base
- ret = read_guest_va_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])) {
- switch(instr[index]) {
- case PREFIX_CS_OVERRIDE:
- case PREFIX_SS_OVERRIDE:
- case PREFIX_DS_OVERRIDE:
- case PREFIX_ES_OVERRIDE:
- case PREFIX_FS_OVERRIDE:
- case PREFIX_GS_OVERRIDE:
- PrintDebug("Segment Override!!\n");
- return -1;
- break;
- default:
- break;
- }
- index++;
- }
-
- /*
- 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;
+ if (info->mem_mode == PHYSICAL_MEM) {
+ ret = read_guest_pa_memory(info, get_addr_linear(info, info->rip, &(info->segments.cs)), 15, instr);
+ } 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->shdw_pg_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");
- SerialMemDump(instr,15);
- return -1;
+ *virt_cr3 = *(struct cr3_32 *)&(info->ctrl_regs.cr3);
}
} else {
- PrintDebug("Invalid operating Mode (0x%x), control registers follow\n", info->cpu_mode);
- PrintV3CtrlRegs(info);
+ PrintError("Unhandled opcode in handle_cr3_read\n");
return -1;
}
+ info->rip += dec_instr.instr_length;
+
return 0;
}
