Palacios Public Git Repository

To checkout Palacios execute

  git clone http://v3vee.org/palacios/palacios.web/palacios.git
This will give you the master branch. You probably want the devel branch or one of the release branches. To switch to the devel branch, simply execute
  cd palacios
  git checkout --track -b devel origin/devel
The other branches are similar.


Context-based output infrastructure (V3_Print, etc) and modifications to use it
[palacios.git] / palacios / src / palacios / vmm_emulator.c
index bb67a5f..1bd777d 100644 (file)
@@ -11,7 +11,8 @@
  * Copyright (c) 2008, The V3VEE Project <http://www.v3vee.org> 
  * All rights reserved.
  *
- * Author: Jack Lange <jarusl@cs.northwestern.edu>
+ * Authors: Jack Lange <jarusl@cs.northwestern.edu>
+ *          Peter Dinda <pdinda@northwestern.edu> (full hook/string ops)
  *
  * This is free software.  You are permitted to use,
  * redistribute, and modify it as specified in the file "V3VEE_LICENSE".
 
 #include <palacios/vmm.h>
 #include <palacios/vmm_emulator.h>
-#include <palacios/vm_guest_mem.h>
 #include <palacios/vmm_decoder.h>
-#include <palacios/vmm_paging.h>
 #include <palacios/vmm_instr_emulator.h>
+#include <palacios/vmm_ctrl_regs.h>
 
-#ifndef DEBUG_EMULATOR
+#ifndef V3_CONFIG_DEBUG_EMULATOR
 #undef PrintDebug
 #define PrintDebug(fmt, args...)
 #endif
 
 
+static int run_op(struct guest_info * info, v3_op_type_t op_type, 
+                 addr_t src_addr, addr_t dst_addr, 
+                 int src_op_size, int dst_op_size) {
+
+    if (src_op_size == 1) {
+       PrintDebug(info->vm_info, info, "Executing 8 bit instruction\n");
+
+       switch (op_type) {
+           case V3_OP_ADC:
+               adc8((addr_t *)dst_addr, (addr_t *)src_addr, (addr_t *)&(info->ctrl_regs.rflags));
+               break;
+           case V3_OP_ADD:
+               add8((addr_t *)dst_addr, (addr_t *)src_addr, (addr_t *)&(info->ctrl_regs.rflags));
+               break;
+           case V3_OP_AND:
+               and8((addr_t *)dst_addr, (addr_t *)src_addr, (addr_t *)&(info->ctrl_regs.rflags));
+               break;
+           case V3_OP_OR:
+               or8((addr_t *)dst_addr, (addr_t *)src_addr, (addr_t *)&(info->ctrl_regs.rflags));
+               break;
+           case V3_OP_XOR:
+               xor8((addr_t *)dst_addr, (addr_t *)src_addr, (addr_t *)&(info->ctrl_regs.rflags));
+               break;
+           case V3_OP_SUB:
+               sub8((addr_t *)dst_addr, (addr_t *)src_addr, (addr_t *)&(info->ctrl_regs.rflags));
+               break;
+
+           case V3_OP_MOV:
+               mov8((addr_t *)dst_addr, (addr_t *)src_addr);
+               break;
+
+           case V3_OP_MOVZX:
+               movzx8((addr_t *)dst_addr, (addr_t *)src_addr, dst_op_size);
+               break;
+           case V3_OP_MOVSX:
+               movsx8((addr_t *)dst_addr, (addr_t *)src_addr, dst_op_size);
+               break;
+
+           case V3_OP_NOT:
+               not8((addr_t *)dst_addr);
+               break;
+           case V3_OP_XCHG:
+               xchg8((addr_t *)dst_addr, (addr_t *)src_addr);
+               break;
+      
 
+           case V3_OP_INC:
+               inc8((addr_t *)dst_addr, (addr_t *)&(info->ctrl_regs.rflags));
+               break;
+           case V3_OP_DEC:
+               dec8((addr_t *)dst_addr, (addr_t *)&(info->ctrl_regs.rflags));
+               break;
+           case V3_OP_NEG:
+               neg8((addr_t *)dst_addr, (addr_t *)&(info->ctrl_regs.rflags));
+               break;
+           case V3_OP_SETB:
+               setb8((addr_t *)dst_addr, (addr_t *)&(info->ctrl_regs.rflags));
+               break;
+           case V3_OP_SETBE:
+               setbe8((addr_t *)dst_addr, (addr_t *)&(info->ctrl_regs.rflags));
+               break;
+           case V3_OP_SETL:
+               setl8((addr_t *)dst_addr, (addr_t *)&(info->ctrl_regs.rflags));
+               break;
+           case V3_OP_SETLE:
+               setle8((addr_t *)dst_addr, (addr_t *)&(info->ctrl_regs.rflags));
+               break;
+           case V3_OP_SETNB:
+               setnb8((addr_t *)dst_addr, (addr_t *)&(info->ctrl_regs.rflags));
+               break;
+           case V3_OP_SETNBE:
+               setnbe8((addr_t *)dst_addr, (addr_t *)&(info->ctrl_regs.rflags));
+               break;
+           case V3_OP_SETNL:
+               setnl8((addr_t *)dst_addr, (addr_t *)&(info->ctrl_regs.rflags));
+               break;
+           case V3_OP_SETNLE:
+               setnle8((addr_t *)dst_addr, (addr_t *)&(info->ctrl_regs.rflags));
+               break;
+           case V3_OP_SETNO:
+               setno8((addr_t *)dst_addr, (addr_t *)&(info->ctrl_regs.rflags));
+               break;
+           case V3_OP_SETNP:
+               setnp8((addr_t *)dst_addr, (addr_t *)&(info->ctrl_regs.rflags));
+               break;
+           case V3_OP_SETNS:
+               setns8((addr_t *)dst_addr, (addr_t *)&(info->ctrl_regs.rflags));
+               break;
+           case V3_OP_SETNZ:
+               setnz8((addr_t *)dst_addr, (addr_t *)&(info->ctrl_regs.rflags));
+               break;
+           case V3_OP_SETO:
+               seto8((addr_t *)dst_addr, (addr_t *)&(info->ctrl_regs.rflags));
+               break;
+           case V3_OP_SETP:
+               setp8((addr_t *)dst_addr, (addr_t *)&(info->ctrl_regs.rflags));
+               break;
+           case V3_OP_SETS:
+               sets8((addr_t *)dst_addr, (addr_t *)&(info->ctrl_regs.rflags));
+               break;
+           case V3_OP_SETZ:
+               setz8((addr_t *)dst_addr, (addr_t *)&(info->ctrl_regs.rflags));
+               break;
+
+           default:
+               PrintError(info->vm_info, info, "Unknown 8 bit instruction\n");
+               return -1;
+       }
+
+    } else if (src_op_size == 2) {
+       PrintDebug(info->vm_info, info, "Executing 16 bit instruction\n");
+
+       switch (op_type) {
+           case V3_OP_ADC:
+               adc16((addr_t *)dst_addr, (addr_t *)src_addr, (addr_t *)&(info->ctrl_regs.rflags));
+               break;
+           case V3_OP_ADD:
+               add16((addr_t *)dst_addr, (addr_t *)src_addr, (addr_t *)&(info->ctrl_regs.rflags));
+               break;
+           case V3_OP_AND:
+               and16((addr_t *)dst_addr, (addr_t *)src_addr, (addr_t *)&(info->ctrl_regs.rflags));
+               break;
+           case V3_OP_OR:
+               or16((addr_t *)dst_addr, (addr_t *)src_addr, (addr_t *)&(info->ctrl_regs.rflags));
+               break;
+           case V3_OP_XOR:
+               xor16((addr_t *)dst_addr, (addr_t *)src_addr, (addr_t *)&(info->ctrl_regs.rflags));
+               break;
+           case V3_OP_SUB:
+               sub16((addr_t *)dst_addr, (addr_t *)src_addr, (addr_t *)&(info->ctrl_regs.rflags));
+               break;
+
+
+           case V3_OP_INC:
+               inc16((addr_t *)dst_addr, (addr_t *)&(info->ctrl_regs.rflags));
+               break;
+           case V3_OP_DEC:
+               dec16((addr_t *)dst_addr, (addr_t *)&(info->ctrl_regs.rflags));
+               break;
+           case V3_OP_NEG:
+               neg16((addr_t *)dst_addr, (addr_t *)&(info->ctrl_regs.rflags));
+               break;
+
+           case V3_OP_MOV:
+               mov16((addr_t *)dst_addr, (addr_t *)src_addr);
+               break;
+           case V3_OP_MOVZX:
+               movzx16((addr_t *)dst_addr, (addr_t *)src_addr, dst_op_size);
+               break;
+           case V3_OP_MOVSX:
+               movsx16((addr_t *)dst_addr, (addr_t *)src_addr, dst_op_size);
+               break;
+           case V3_OP_NOT:
+               not16((addr_t *)dst_addr);
+               break;
+           case V3_OP_XCHG:
+               xchg16((addr_t *)dst_addr, (addr_t *)src_addr);
+               break;
+      
+           default:
+               PrintError(info->vm_info, info, "Unknown 16 bit instruction\n");
+               return -1;
+       }
+
+    } else if (src_op_size == 4) {
+       PrintDebug(info->vm_info, info, "Executing 32 bit instruction\n");
+
+       switch (op_type) {
+           case V3_OP_ADC:
+               adc32((addr_t *)dst_addr, (addr_t *)src_addr, (addr_t *)&(info->ctrl_regs.rflags));
+               break;
+           case V3_OP_ADD:
+               add32((addr_t *)dst_addr, (addr_t *)src_addr, (addr_t *)&(info->ctrl_regs.rflags));
+               break;
+           case V3_OP_AND:
+               and32((addr_t *)dst_addr, (addr_t *)src_addr, (addr_t *)&(info->ctrl_regs.rflags));
+               break;
+           case V3_OP_OR:
+               or32((addr_t *)dst_addr, (addr_t *)src_addr, (addr_t *)&(info->ctrl_regs.rflags));
+               break;
+           case V3_OP_XOR:
+               xor32((addr_t *)dst_addr, (addr_t *)src_addr, (addr_t *)&(info->ctrl_regs.rflags));
+               break;
+           case V3_OP_SUB:
+               sub32((addr_t *)dst_addr, (addr_t *)src_addr, (addr_t *)&(info->ctrl_regs.rflags));
+               break;
+
+           case V3_OP_INC:
+               inc32((addr_t *)dst_addr, (addr_t *)&(info->ctrl_regs.rflags));
+               break;
+           case V3_OP_DEC:
+               dec32((addr_t *)dst_addr, (addr_t *)&(info->ctrl_regs.rflags));
+               break;
+           case V3_OP_NEG:
+               neg32((addr_t *)dst_addr, (addr_t *)&(info->ctrl_regs.rflags));
+               break;
+
+           case V3_OP_MOV:
+               mov32((addr_t *)dst_addr, (addr_t *)src_addr);
+               break;
+
+           case V3_OP_NOT:
+               not32((addr_t *)dst_addr);
+               break;
+           case V3_OP_XCHG:
+               xchg32((addr_t *)dst_addr, (addr_t *)src_addr);
+               break;
+      
+           default:
+               PrintError(info->vm_info, info, "Unknown 32 bit instruction\n");
+               return -1;
+       }
+
+#ifdef __V3_64BIT__
+    } else if (src_op_size == 8) {
+       PrintDebug(info->vm_info, info, "Executing 64 bit instruction\n");
+
+       switch (op_type) {
+           case V3_OP_ADC:
+               adc64((addr_t *)dst_addr, (addr_t *)src_addr, (addr_t *)&(info->ctrl_regs.rflags));
+               break;
+           case V3_OP_ADD:
+               add64((addr_t *)dst_addr, (addr_t *)src_addr, (addr_t *)&(info->ctrl_regs.rflags));
+               break;
+           case V3_OP_AND:
+               and64((addr_t *)dst_addr, (addr_t *)src_addr, (addr_t *)&(info->ctrl_regs.rflags));
+               break;
+           case V3_OP_OR:
+               or64((addr_t *)dst_addr, (addr_t *)src_addr, (addr_t *)&(info->ctrl_regs.rflags));
+               break;
+           case V3_OP_XOR:
+               xor64((addr_t *)dst_addr, (addr_t *)src_addr, (addr_t *)&(info->ctrl_regs.rflags));
+               break;
+           case V3_OP_SUB:
+               sub64((addr_t *)dst_addr, (addr_t *)src_addr, (addr_t *)&(info->ctrl_regs.rflags));
+               break;
+
+           case V3_OP_INC:
+               inc64((addr_t *)dst_addr, (addr_t *)&(info->ctrl_regs.rflags));
+               break;
+           case V3_OP_DEC:
+               dec64((addr_t *)dst_addr, (addr_t *)&(info->ctrl_regs.rflags));
+               break;
+           case V3_OP_NEG:
+               neg64((addr_t *)dst_addr, (addr_t *)&(info->ctrl_regs.rflags));
+               break;
+
+           case V3_OP_MOV:
+               mov64((addr_t *)dst_addr, (addr_t *)src_addr);
+               break;
+
+           case V3_OP_NOT:
+               not64((addr_t *)dst_addr);
+               break;
+           case V3_OP_XCHG:
+               xchg64((addr_t *)dst_addr, (addr_t *)src_addr);
+               break;
+      
+           default:
+               PrintError(info->vm_info, info, "Unknown 64 bit instruction\n");
+               return -1;
+       }
+#endif
 
-
-
-// We emulate up to the next 4KB page boundry
-static int emulate_string_write_op(struct guest_info * info, struct x86_instr * dec_instr, 
-                                  addr_t write_gva, addr_t write_gpa, addr_t * dst_addr) {
-  uint_t emulation_length = 0;
-  addr_t tmp_rcx = 0;
-  addr_t src_addr = 0;
-
-  if (dec_instr->op_type == V3_OP_MOVS) {
-    PrintDebug("MOVS emulation\n");
-
-    if (dec_instr->dst_operand.operand != write_gva) {
-      PrintError("Inconsistency between Pagefault and Instruction Decode XED_ADDR=%p, PF_ADDR=%p\n",
-                (void *)dec_instr->dst_operand.operand, (void *)write_gva);
-      return -1;
-    }
-
-    emulation_length = ( (dec_instr->str_op_length  < (0x1000 - PAGE_OFFSET_4KB(write_gva))) ? 
-                        dec_instr->str_op_length :
-                        (0x1000 - PAGE_OFFSET_4KB(write_gva)));
-    /* ** Fix emulation length so that it doesn't overrun over the src page either ** */
-
-
-    PrintDebug("STR_OP_LEN: %d, Page Len: %d\n", 
-              (uint_t)dec_instr->str_op_length, 
-              (uint_t)(0x1000 - PAGE_OFFSET_4KB(write_gva)));
-    PrintDebug("Emulation length: %d\n", emulation_length);
-    tmp_rcx = emulation_length;
-    if (guest_pa_to_host_va(info, write_gpa, dst_addr) == -1) {
-      PrintError("Could not translate write destination to host VA\n");
-      return -1;
-    }
-
-    // figure out addresses here....
-    if (info->mem_mode == PHYSICAL_MEM) {
-      if (guest_pa_to_host_va(info, dec_instr->src_operand.operand, &src_addr) == -1) {
-       PrintError("Could not translate write Source (Physical) to host VA\n");
-       return -1;
-      }
     } else {
-      if (guest_va_to_host_va(info, dec_instr->src_operand.operand, &src_addr) == -1) {
-       PrintError("Could not translate write Source (Virtual) to host VA\n");
+       PrintError(info->vm_info, info, "Invalid Operation Size\n");
        return -1;
-      }
     }
 
+    return 0;
+}
 
-    PrintDebug("Dst Operand: %p (size=%d), Src Operand: %p\n", 
-              (void *)dec_instr->dst_operand.operand, 
-              dec_instr->dst_operand.size,
-              (void *)dec_instr->src_operand.operand);
-    PrintDebug("Dst Addr: %p, Src Addr: %p\n", (void *)(addr_t *)*dst_addr, (void *)src_addr);
 
-    //return -1;
 
+/* Returns the number of bytes written, or -1 if there is an error */
+static int run_str_op(struct guest_info * core, struct x86_instr * instr, 
+                     addr_t src_addr, addr_t dst_addr, 
+                     int op_size, int rep_cnt) {
 
+    addr_t tmp_rcx = rep_cnt;
+    int emulation_length = op_size * rep_cnt;
+    struct rflags * flags_reg = (struct rflags *)&(core->ctrl_regs.rflags);
 
 
-    if (dec_instr->dst_operand.size == 1) {
-      movs8(dst_addr, &src_addr, &tmp_rcx, (addr_t *)&(info->ctrl_regs.rflags));
-    } else if (dec_instr->dst_operand.size == 2) {
-      movs16(dst_addr, &src_addr, &tmp_rcx, (addr_t *)&(info->ctrl_regs.rflags));
-    } else if (dec_instr->dst_operand.size == 4) {
-      movs32(dst_addr, &src_addr, &tmp_rcx, (addr_t *)&(info->ctrl_regs.rflags));
-    } else {
-      PrintError("Invalid operand length\n");
-      return -1;
-    }
-
+    PrintDebug(core->vm_info, core, "Emulation_len=%d, tmp_rcx=%d\n", emulation_length, (uint_t)tmp_rcx);
 
 
+    if (instr->op_type == V3_OP_MOVS) {
+       if (op_size== 1) {
+           movs8((addr_t *)&dst_addr, &src_addr, &tmp_rcx, (addr_t *)&(core->ctrl_regs.rflags));
+       } else if (op_size == 2) {
+           movs16((addr_t *)&dst_addr, &src_addr, &tmp_rcx, (addr_t *)&(core->ctrl_regs.rflags));
+       } else if (op_size == 4) {
+           movs32((addr_t *)&dst_addr, &src_addr, &tmp_rcx, (addr_t *)&(core->ctrl_regs.rflags));
+#ifdef __V3_64BIT__
+       } else if (op_size == 8) {
+           movs64((addr_t *)&dst_addr, &src_addr, &tmp_rcx, (addr_t *)&(core->ctrl_regs.rflags));
+#endif
+       } else {
+           PrintError(core->vm_info, core, "Invalid operand length\n");
+           return -1;
+       }
+
+       if (flags_reg->df == 0) {
+           core->vm_regs.rdi += emulation_length;
+           core->vm_regs.rsi += emulation_length;
+       } else {
+           core->vm_regs.rdi -= emulation_length;
+           core->vm_regs.rsi -= emulation_length;
+       }
+
+       // RCX is only modified if the rep prefix is present
+       if (instr->prefixes.rep == 1) {
+           core->vm_regs.rcx -= rep_cnt;
+       }
+
+     } else if (instr->op_type == V3_OP_STOS) {
+       if (op_size == 1) {
+           stos8((addr_t *)&dst_addr, (addr_t  *)&(core->vm_regs.rax), &tmp_rcx, (addr_t *)&(core->ctrl_regs.rflags));
+       } else if (op_size == 2) {
+           stos16((addr_t *)&dst_addr, (addr_t  *)&(core->vm_regs.rax), &tmp_rcx, (addr_t *)&(core->ctrl_regs.rflags));
+       } else if (op_size == 4) {
+           stos32((addr_t *)&dst_addr, (addr_t  *)&(core->vm_regs.rax), &tmp_rcx, (addr_t *)&(core->ctrl_regs.rflags));
+#ifdef __V3_64BIT__
+       } else if (op_size == 8) {
+           stos64((addr_t *)&dst_addr, (addr_t  *)&(core->vm_regs.rax), &tmp_rcx, (addr_t *)&(core->ctrl_regs.rflags));
+#endif
+       } else {
+           PrintError(core->vm_info, core, "Invalid operand length\n");
+           return -1;
+       }
 
 
-    PrintDebug("RDI=%p, RSI=%p, RCX=%p\n", 
-              (void *)*(addr_t *)&(info->vm_regs.rdi), 
-              (void *)*(addr_t *)&(info->vm_regs.rsi), 
-              (void *)*(addr_t *)&(info->vm_regs.rcx)); 
 
-    info->vm_regs.rdi += emulation_length;
-    info->vm_regs.rsi += emulation_length;
-    info->vm_regs.rcx -= emulation_length;
-    
-    PrintDebug("RDI=%p, RSI=%p, RCX=%p\n", 
-              (void *)*(addr_t *)&(info->vm_regs.rdi), 
-              (void *)*(addr_t *)&(info->vm_regs.rsi), 
-              (void *)*(addr_t *)&(info->vm_regs.rcx)); 
+       if (flags_reg->df == 0) {
+           core->vm_regs.rdi += emulation_length;
+       } else {
+           core->vm_regs.rdi -= emulation_length;
+       }
 
-    if (emulation_length == dec_instr->str_op_length) {
-      info->rip += dec_instr->instr_length;
+       // RCX is only modified if the rep prefix is present
+       if (instr->prefixes.rep == 1) {
+           core->vm_regs.rcx -= rep_cnt;
+       }
+    } else {
+       PrintError(core->vm_info, core, "Unimplemented String operation\n");
+       return -1;
     }
-
+    
     return emulation_length;
-  }
-
-  
-
-
-  return -1;
 }
 
 
-int v3_emulate_write_op(struct guest_info * info, addr_t write_gva, addr_t write_gpa, addr_t * dst_addr) {
-  struct x86_instr dec_instr;
-  uchar_t instr[15];
-  int ret = 0;
-  addr_t src_addr = 0;
-
-
-  PrintDebug("Emulating Write for instruction at %p\n", (void *)(addr_t)(info->rip));
-  PrintDebug("GPA=%p, GVA=%p\n", (void *)write_gpa, (void *)write_gva);
-
-  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 == -1) {
-    return -1;
-  }
 
+int v3_emulate(struct guest_info * core, struct x86_instr * instr, 
+              int mem_op_size, addr_t mem_hva_src, addr_t mem_hva_dst) {
 
-  if (guest_pa_to_host_va(info, write_gpa, dst_addr) == -1) {
-    PrintError("Could not translate write destination to host VA\n");
-    return -1;
-  }
+    addr_t src_hva = 0;
+    addr_t dst_hva = 0;
 
-  if (v3_decode(info, (addr_t)instr, &dec_instr) == -1) {
-    PrintError("Decoding Error\n");
-    // Kick off single step emulator
-    return -1;
-  }
-  
-  if (dec_instr.is_str_op) {
-    return emulate_string_write_op(info, &dec_instr, write_gva, write_gpa, dst_addr);
-  }
 
+    if (instr->src_operand.type == MEM_OPERAND) {
+       src_hva = mem_hva_src;
+    } else if (instr->src_operand.type == REG_OPERAND) {
+       src_hva = instr->src_operand.operand;
+    } else {
+       src_hva = (addr_t)&(instr->src_operand.operand);
+    }
 
-  if ((dec_instr.dst_operand.type != MEM_OPERAND) ||
-      (dec_instr.dst_operand.operand != write_gva)) {
-    PrintError("Inconsistency between Pagefault and Instruction Decode XED_ADDR=%p, PF_ADDR=%p\n",
-              (void *)dec_instr.dst_operand.operand, (void *)write_gva);
-    return -1;
-  }
+    if (instr->dst_operand.type == MEM_OPERAND) {
+       dst_hva = mem_hva_dst;
+    } else if (instr->dst_operand.type == REG_OPERAND) {
+       dst_hva = instr->dst_operand.operand;
+    } else {
+       dst_hva = (addr_t)&(instr->dst_operand.operand);
+    }
 
+    if (instr->is_str_op == 0) {
+       int src_op_len = instr->src_operand.size;
+       int dst_op_len = instr->dst_operand.size;
+       
+       run_op(core, instr->op_type, src_hva, dst_hva, src_op_len, dst_op_len);
 
-  if (dec_instr.src_operand.type == MEM_OPERAND) {
-    if (info->mem_mode == PHYSICAL_MEM) {
-      if (guest_pa_to_host_va(info, dec_instr.src_operand.operand, &src_addr) == -1) {
-       PrintError("Could not translate write Source (Physical) to host VA\n");
-       return -1;
-      }
+       return dst_op_len;
     } else {
-      if (guest_va_to_host_va(info, dec_instr.src_operand.operand, &src_addr) == -1) {
-       PrintError("Could not translate write Source (Virtual) to host VA\n");
-       return -1;
-      }
-    }
-  } else if (dec_instr.src_operand.type == REG_OPERAND) {
-    src_addr = dec_instr.src_operand.operand;
-  } else {
-    src_addr = (addr_t)&(dec_instr.src_operand.operand);
-  }
-
-
-  PrintDebug("Dst_Addr Ptr = %p (val=%p), SRC operand = %p\n", 
-            (void *)dst_addr, (void *)*dst_addr, (void *)src_addr);
-
-
-  if (dec_instr.dst_operand.size == 1) {
-
-    switch (dec_instr.op_type) {
-    case V3_OP_ADC:
-      adc8((addr_t *)*dst_addr, (addr_t *)src_addr, (addr_t *)&(info->ctrl_regs.rflags));
-      break;
-    case V3_OP_ADD:
-      add8((addr_t *)*dst_addr, (addr_t *)src_addr, (addr_t *)&(info->ctrl_regs.rflags));
-      break;
-    case V3_OP_AND:
-      and8((addr_t *)*dst_addr, (addr_t *)src_addr, (addr_t *)&(info->ctrl_regs.rflags));
-      break;
-    case V3_OP_OR:
-      or8((addr_t *)*dst_addr, (addr_t *)src_addr, (addr_t *)&(info->ctrl_regs.rflags));
-      break;
-    case V3_OP_XOR:
-      xor8((addr_t *)*dst_addr, (addr_t *)src_addr, (addr_t *)&(info->ctrl_regs.rflags));
-      break;
-    case V3_OP_SUB:
-      sub8((addr_t *)*dst_addr, (addr_t *)src_addr, (addr_t *)&(info->ctrl_regs.rflags));
-      break;
-
-    case V3_OP_MOV:
-      mov8((addr_t *)*dst_addr, (addr_t *)src_addr);
-      break;
-    case V3_OP_NOT:
-      not8((addr_t *)*dst_addr);
-      break;
-    case V3_OP_XCHG:
-      xchg8((addr_t *)*dst_addr, (addr_t *)src_addr);
-      break;
-      
+       // String Operation
+       int rep_cnt = 0;
 
-    case V3_OP_INC:
-      inc8((addr_t *)*dst_addr, (addr_t *)&(info->ctrl_regs.rflags));
-      break;
-    case V3_OP_DEC:
-      dec8((addr_t *)*dst_addr, (addr_t *)&(info->ctrl_regs.rflags));
-      break;
-    case V3_OP_NEG:
-      neg8((addr_t *)*dst_addr, (addr_t *)&(info->ctrl_regs.rflags));
-      break;
-    case V3_OP_SETB:
-      setb8((addr_t *)*dst_addr, (addr_t *)&(info->ctrl_regs.rflags));
-      break;
-    case V3_OP_SETBE:
-      setbe8((addr_t *)*dst_addr, (addr_t *)&(info->ctrl_regs.rflags));
-      break;
-    case V3_OP_SETL:
-      setl8((addr_t *)*dst_addr, (addr_t *)&(info->ctrl_regs.rflags));
-      break;
-    case V3_OP_SETLE:
-      setle8((addr_t *)*dst_addr, (addr_t *)&(info->ctrl_regs.rflags));
-      break;
-    case V3_OP_SETNB:
-      setnb8((addr_t *)*dst_addr, (addr_t *)&(info->ctrl_regs.rflags));
-      break;
-    case V3_OP_SETNBE:
-      setnbe8((addr_t *)*dst_addr, (addr_t *)&(info->ctrl_regs.rflags));
-      break;
-    case V3_OP_SETNL:
-      setnl8((addr_t *)*dst_addr, (addr_t *)&(info->ctrl_regs.rflags));
-      break;
-    case V3_OP_SETNLE:
-      setnle8((addr_t *)*dst_addr, (addr_t *)&(info->ctrl_regs.rflags));
-      break;
-    case V3_OP_SETNO:
-      setno8((addr_t *)*dst_addr, (addr_t *)&(info->ctrl_regs.rflags));
-      break;
-    case V3_OP_SETNP:
-      setnp8((addr_t *)*dst_addr, (addr_t *)&(info->ctrl_regs.rflags));
-      break;
-    case V3_OP_SETNS:
-      setns8((addr_t *)*dst_addr, (addr_t *)&(info->ctrl_regs.rflags));
-      break;
-    case V3_OP_SETNZ:
-      setnz8((addr_t *)*dst_addr, (addr_t *)&(info->ctrl_regs.rflags));
-      break;
-    case V3_OP_SETO:
-      seto8((addr_t *)*dst_addr, (addr_t *)&(info->ctrl_regs.rflags));
-      break;
-    case V3_OP_SETP:
-      setp8((addr_t *)*dst_addr, (addr_t *)&(info->ctrl_regs.rflags));
-      break;
-    case V3_OP_SETS:
-      sets8((addr_t *)*dst_addr, (addr_t *)&(info->ctrl_regs.rflags));
-      break;
-    case V3_OP_SETZ:
-      setz8((addr_t *)*dst_addr, (addr_t *)&(info->ctrl_regs.rflags));
-      break;
-
-    default:
-      PrintError("Unknown 8 bit instruction\n");
-      return -1;
-    }
+       /* Both src and dst operand sizes should be identical */
+       rep_cnt = mem_op_size / instr->src_operand.size;
 
-  } else if (dec_instr.dst_operand.size == 2) {
-
-    switch (dec_instr.op_type) {
-    case V3_OP_ADC:
-      adc16((addr_t *)*dst_addr, (addr_t *)src_addr, (addr_t *)&(info->ctrl_regs.rflags));
-      break;
-    case V3_OP_ADD:
-      add16((addr_t *)*dst_addr, (addr_t *)src_addr, (addr_t *)&(info->ctrl_regs.rflags));
-      break;
-    case V3_OP_AND:
-      and16((addr_t *)*dst_addr, (addr_t *)src_addr, (addr_t *)&(info->ctrl_regs.rflags));
-      break;
-    case V3_OP_OR:
-      or16((addr_t *)*dst_addr, (addr_t *)src_addr, (addr_t *)&(info->ctrl_regs.rflags));
-      break;
-    case V3_OP_XOR:
-      xor16((addr_t *)*dst_addr, (addr_t *)src_addr, (addr_t *)&(info->ctrl_regs.rflags));
-      break;
-    case V3_OP_SUB:
-      sub16((addr_t *)*dst_addr, (addr_t *)src_addr, (addr_t *)&(info->ctrl_regs.rflags));
-      break;
-
-
-    case V3_OP_INC:
-      inc16((addr_t *)*dst_addr, (addr_t *)&(info->ctrl_regs.rflags));
-      break;
-    case V3_OP_DEC:
-      dec16((addr_t *)*dst_addr, (addr_t *)&(info->ctrl_regs.rflags));
-      break;
-    case V3_OP_NEG:
-      neg16((addr_t *)*dst_addr, (addr_t *)&(info->ctrl_regs.rflags));
-      break;
-
-    case V3_OP_MOV:
-      mov16((addr_t *)*dst_addr, (addr_t *)src_addr);
-      break;
-    case V3_OP_NOT:
-      not16((addr_t *)*dst_addr);
-      break;
-    case V3_OP_XCHG:
-      xchg16((addr_t *)*dst_addr, (addr_t *)src_addr);
-      break;
-      
-    default:
-      PrintError("Unknown 16 bit instruction\n");
-      return -1;
+       return run_str_op(core, instr, src_hva, dst_hva, instr->src_operand.size, rep_cnt);
     }
 
-  } else if (dec_instr.dst_operand.size == 4) {
-
-    switch (dec_instr.op_type) {
-    case V3_OP_ADC:
-      adc32((addr_t *)*dst_addr, (addr_t *)src_addr, (addr_t *)&(info->ctrl_regs.rflags));
-      break;
-    case V3_OP_ADD:
-      add32((addr_t *)*dst_addr, (addr_t *)src_addr, (addr_t *)&(info->ctrl_regs.rflags));
-      break;
-    case V3_OP_AND:
-      and32((addr_t *)*dst_addr, (addr_t *)src_addr, (addr_t *)&(info->ctrl_regs.rflags));
-      break;
-    case V3_OP_OR:
-      or32((addr_t *)*dst_addr, (addr_t *)src_addr, (addr_t *)&(info->ctrl_regs.rflags));
-      break;
-    case V3_OP_XOR:
-      xor32((addr_t *)*dst_addr, (addr_t *)src_addr, (addr_t *)&(info->ctrl_regs.rflags));
-      break;
-    case V3_OP_SUB:
-      sub32((addr_t *)*dst_addr, (addr_t *)src_addr, (addr_t *)&(info->ctrl_regs.rflags));
-      break;
-
-    case V3_OP_INC:
-      inc32((addr_t *)*dst_addr, (addr_t *)&(info->ctrl_regs.rflags));
-      break;
-    case V3_OP_DEC:
-      dec32((addr_t *)*dst_addr, (addr_t *)&(info->ctrl_regs.rflags));
-      break;
-    case V3_OP_NEG:
-      neg32((addr_t *)*dst_addr, (addr_t *)&(info->ctrl_regs.rflags));
-      break;
-
-    case V3_OP_MOV:
-      mov32((addr_t *)*dst_addr, (addr_t *)src_addr);
-      break;
-    case V3_OP_NOT:
-      not32((addr_t *)*dst_addr);
-      break;
-    case V3_OP_XCHG:
-      xchg32((addr_t *)*dst_addr, (addr_t *)src_addr);
-      break;
-      
-    default:
-      PrintError("Unknown 32 bit instruction\n");
-      return -1;
-    }
 
-  } else if (dec_instr.dst_operand.size == 8) {
-    PrintError("64 bit instructions not handled\n");
-    return -1;
-  } else {
-    PrintError("Invalid Operation Size\n");
     return -1;
-  }
-
-  info->rip += dec_instr.instr_length;
-
-  return dec_instr.dst_operand.size;
 }
-