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.

projects / palacios.git / blobdiff
? search: re
summary | shortlog | log | commit | commitdiff | tree
raw
clear instruction to 0 before decoding with xed
[palacios.git] / palacios / src / palacios / vmm_v3dec.c
diff --git a/palacios/src/palacios/vmm_v3dec.c b/palacios/src/palacios/vmm_v3dec.c
index f02d04b..4fa6e04 100644 (file)
--- a/palacios/src/palacios/vmm_v3dec.c
+++ b/palacios/src/palacios/vmm_v3dec.c
@@ -20,34 +20,30 @@
 #include <palacios/vmm_decoder.h>
 #include <palacios/vmm_instr_decoder.h>
 
-
-/* Disgusting mask hack...
-   I can't think right now, so we'll do it this way...
-*/
-static const ullong_t mask_1 = 0x00000000000000ffLL;
-static const ullong_t mask_2 = 0x000000000000ffffLL;
-static const ullong_t mask_4 = 0x00000000ffffffffLL;
-static const ullong_t mask_8 = 0xffffffffffffffffLL;
-
-
-#define MASK(val, length) ({                   \
-           ullong_t mask = 0x0LL;              \
-           switch (length) {                   \
-               case 1:                         \
-                   mask = mask_1;              \
-                   break;                      \
-               case 2:                         \
-                   mask = mask_2;              \
-                   break;                      \
-               case 4:                         \
-                   mask = mask_4;              \
-                   break;                      \
-               case 8:                         \
-                   mask = mask_8;              \
-                   break;                      \
-           }                                   \
-           val & mask;                         \
-       })
+#ifndef CONFIG_DEBUG_DECODER
+#undef PrintDebug
+#define PrintDebug(fmt, args...)
+#endif
+
+
+#define MASK(val, length) ({                                           \
+            uint64_t mask = 0x0LL;                                     \
+            switch (length) {                                          \
+               case 1:                                                 \
+                   mask = 0x00000000000000ffLL;                        \
+                    break;                                             \
+                case 2:                                                        \
+                    mask = 0x000000000000ffffLL;                       \
+                    break;                                             \
+                case 4:                                                        \
+                    mask = 0x00000000ffffffffLL;                       \
+                    break;                                             \
+                case 8:                                                        \
+                    mask = 0xffffffffffffffffLL;                       \
+                    break;                                             \
+            }                                                          \
+            val & mask;                                                        \
+        })
 
 static v3_op_type_t op_form_to_type(op_form_t form);
 static int parse_operands(struct guest_info * core, uint8_t * instr_ptr, struct x86_instr * instr, op_form_t form);
@@ -87,12 +83,25 @@ int v3_decode(struct guest_info * core, addr_t instr_ptr, struct x86_instr * ins
     length = v3_get_prefixes((uint8_t *)instr_ptr, &(instr->prefixes));
 
 
-    // check for REX prefix
+    // REX prefix
+    if (v3_get_vm_cpu_mode(core) == LONG) {
+       uint8_t prefix = *(uint8_t *)(instr_ptr + length);
 
+       if ((prefix & 0xf0) == 0x40) {
+           instr->prefixes.rex = 1;
 
-    form = op_code_to_form((uint8_t *)(instr_ptr + length), &length);
+           instr->prefixes.rex_rm = (prefix & 0x01);
+           instr->prefixes.rex_sib_idx = ((prefix & 0x02) >> 1);
+           instr->prefixes.rex_reg = ((prefix & 0x04) >> 2);
+           instr->prefixes.rex_op_size = ((prefix & 0x08) >> 3);
+
+           length += 1;
+       }
+    }
 
 
+    form = op_code_to_form((uint8_t *)(instr_ptr + length), &length);
+
     V3_Print("\t decoded as (%s)\n", op_form_to_str(form));
 
     if (form == INVALID_INSTR) {
@@ -109,11 +118,9 @@ int v3_decode(struct guest_info * core, addr_t instr_ptr, struct x86_instr * ins
        return -1;
     }
     length += ret;
-    
 
     instr->instr_length += length;
 
-
     v3_print_instr(instr);
 
     return 0;
@@ -124,7 +131,7 @@ static int parse_operands(struct guest_info * core, uint8_t * instr_ptr,
                          struct x86_instr * instr, op_form_t form) {
     // get operational mode of the guest for operand width
     uint8_t operand_width = get_operand_width(core, instr, form);
-    uint8_t addr_width = get_addr_width(core, instr, form);
+    uint8_t addr_width = get_addr_width(core, instr);
     int ret = 0;
     uint8_t * instr_start = instr_ptr;
     
@@ -148,9 +155,7 @@ static int parse_operands(struct guest_info * core, uint8_t * instr_ptr,
        case MOV_IMM2:{
            uint8_t reg_code = 0;
 
-           instr->dst_operand.size = operand_width;
-
-           ret = decode_rm_operand(core, instr_ptr, instr, &(instr->dst_operand), &reg_code);
+           ret = decode_rm_operand(core, instr_ptr, form, instr, &(instr->dst_operand), &reg_code);
 
            if (ret == -1) {
                PrintError("Error decoding operand\n");
@@ -162,6 +167,7 @@ static int parse_operands(struct guest_info * core, uint8_t * instr_ptr,
            instr->src_operand.type = IMM_OPERAND;
            instr->src_operand.size = operand_width;
 
+
            if (operand_width == 1) {
                instr->src_operand.operand = *(uint8_t *)instr_ptr;
            } else if (operand_width == 2) {
@@ -173,6 +179,9 @@ static int parse_operands(struct guest_info * core, uint8_t * instr_ptr,
                return -1;
            }
 
+           instr->src_operand.read = 1;
+           instr->dst_operand.write = 1;
+
            instr_ptr += operand_width;
 
            instr->num_operands = 2;
@@ -195,9 +204,7 @@ static int parse_operands(struct guest_info * core, uint8_t * instr_ptr,
        case MOV_2MEM: {
            uint8_t reg_code = 0;
 
-           instr->dst_operand.size = operand_width;
-
-           ret = decode_rm_operand(core, instr_ptr, instr, &(instr->dst_operand), &reg_code);
+           ret = decode_rm_operand(core, instr_ptr, form, instr, &(instr->dst_operand), &reg_code);
 
            if (ret == -1) {
                PrintError("Error decoding operand\n");
@@ -209,6 +216,10 @@ static int parse_operands(struct guest_info * core, uint8_t * instr_ptr,
            instr->src_operand.type = REG_OPERAND;
            instr->src_operand.size = operand_width;
 
+           instr->src_operand.read = 1;
+           instr->dst_operand.write = 1;
+
+
            decode_gpr(core, reg_code, &(instr->src_operand));
 
            instr->num_operands = 2;
@@ -229,9 +240,8 @@ static int parse_operands(struct guest_info * core, uint8_t * instr_ptr,
        case XOR_MEM2:
        case MOV_MEM2: {
            uint8_t reg_code = 0;
-           instr->src_operand.size = operand_width;
 
-           ret = decode_rm_operand(core, instr_ptr, instr, &(instr->src_operand), &reg_code);
+           ret = decode_rm_operand(core, instr_ptr, form, instr, &(instr->src_operand), &reg_code);
 
            if (ret == -1) {
                PrintError("Error decoding operand\n");
@@ -244,6 +254,59 @@ static int parse_operands(struct guest_info * core, uint8_t * instr_ptr,
            instr->dst_operand.type = REG_OPERAND;
            decode_gpr(core, reg_code, &(instr->dst_operand));
 
+           instr->src_operand.read = 1;
+           instr->dst_operand.write = 1;
+
+           instr->num_operands = 2;
+
+           break;
+       }
+       case MOVSX_8:
+       case MOVZX_8: {
+           uint8_t reg_code = 0;
+
+           ret = decode_rm_operand(core, instr_ptr, form, instr, &(instr->src_operand), &reg_code);
+           instr->src_operand.size = 1;
+
+           if (ret == -1) {
+               PrintError("Error decoding operand\n");
+               return -1;
+           }
+
+           instr_ptr += ret;
+
+           instr->dst_operand.size = operand_width;
+           instr->dst_operand.type = REG_OPERAND;
+           decode_gpr(core, reg_code, &(instr->dst_operand));
+
+           instr->src_operand.read = 1;
+           instr->dst_operand.write = 1;
+
+           instr->num_operands = 2;
+
+           break;
+       }
+       case MOVSX:
+       case MOVZX: {
+           uint8_t reg_code = 0;
+
+           ret = decode_rm_operand(core, instr_ptr, form, instr, &(instr->src_operand), &reg_code);
+           instr->src_operand.size = 2;
+
+           if (ret == -1) {
+               PrintError("Error decoding operand\n");
+               return -1;
+           }
+
+           instr_ptr += ret;
+
+           instr->dst_operand.size = operand_width;
+           instr->dst_operand.type = REG_OPERAND;
+           decode_gpr(core, reg_code, &(instr->dst_operand));
+
+           instr->src_operand.read = 1;
+           instr->dst_operand.write = 1;
+
            instr->num_operands = 2;
 
            break;
@@ -255,9 +318,8 @@ static int parse_operands(struct guest_info * core, uint8_t * instr_ptr,
        case SUB_IMM2SX_8:
        case XOR_IMM2SX_8: {
            uint8_t reg_code = 0;
-           instr->src_operand.size = operand_width;
 
-           ret = decode_rm_operand(core, instr_ptr, instr, &(instr->src_operand), &reg_code);
+           ret = decode_rm_operand(core, instr_ptr, form, instr, &(instr->dst_operand), &reg_code);
 
            if (ret == -1) {
                PrintError("Error decoding operand\n");
@@ -268,7 +330,10 @@ static int parse_operands(struct guest_info * core, uint8_t * instr_ptr,
 
            instr->src_operand.type = IMM_OPERAND;
            instr->src_operand.size = operand_width;
-           instr->src_operand.operand = *(sint8_t *)instr_ptr;  // sign extend.
+           instr->src_operand.operand = (addr_t)MASK((sint64_t)*(sint8_t *)instr_ptr, operand_width);  // sign extend.
+
+           instr->src_operand.read = 1;
+           instr->dst_operand.write = 1;
 
            instr_ptr += 1;
 
@@ -293,104 +358,109 @@ static int parse_operands(struct guest_info * core, uint8_t * instr_ptr,
            instr->src_operand.size = operand_width;
            instr->src_operand.operand = get_addr_linear(core,  MASK(core->vm_regs.rsi, addr_width), &(core->segments.ds));
 
+
            instr->dst_operand.type = MEM_OPERAND;
            instr->dst_operand.size = operand_width;
            instr->dst_operand.operand = get_addr_linear(core, MASK(core->vm_regs.rdi, addr_width), &(core->segments.es));
 
-           instr->num_operands = 2;
-
-           break;
 
-           case MOV_2CR: {
-               uint8_t reg_code = 0;
+           instr->src_operand.read = 1;
+           instr->dst_operand.write = 1;
 
-               instr->src_operand.size = operand_width;
+           instr->num_operands = 2;
 
-               ret = decode_rm_operand(core, instr_ptr, instr, &(instr->src_operand),
-                                       &reg_code);
+           break;
+       }
+       case MOV_2CR: {
+           uint8_t reg_code = 0;
+           
+           ret = decode_rm_operand(core, instr_ptr, form, instr, &(instr->src_operand),
+                                   &reg_code);
 
-               if (ret == -1) {
-                   PrintError("Error decoding operand for (%s)\n", op_form_to_str(form));
-                   return -1;
-               }
+           if (ret == -1) {
+               PrintError("Error decoding operand for (%s)\n", op_form_to_str(form));
+               return -1;
+           }
                
-               instr_ptr += ret;
+           instr_ptr += ret;
 
-               instr->dst_operand.type = REG_OPERAND;
-               instr->dst_operand.size = operand_width;
-               decode_cr(core, reg_code, &(instr->dst_operand));
+           instr->dst_operand.type = REG_OPERAND;
+           instr->dst_operand.size = operand_width;
+           decode_cr(core, reg_code, &(instr->dst_operand));
+           
+           instr->src_operand.read = 1;
+           instr->dst_operand.write = 1;
 
-               instr->num_operands = 2;
-               break;
+           instr->num_operands = 2;
+           break;
+       }
+       case MOV_CR2: {
+           uint8_t reg_code = 0;
+           
+           ret = decode_rm_operand(core, instr_ptr, form, instr, &(instr->dst_operand),
+                                   &reg_code);
+           
+           if (ret == -1) {
+               PrintError("Error decoding operand for (%s)\n", op_form_to_str(form));
+               return -1;
            }
-           case MOV_CR2: {
-               uint8_t reg_code = 0;
-
-               instr->dst_operand.size = operand_width;
-
-               ret = decode_rm_operand(core, instr_ptr, instr, &(instr->dst_operand),
-                                       &reg_code);
-
-               if (ret == -1) {
-                   PrintError("Error decoding operand for (%s)\n", op_form_to_str(form));
-                   return -1;
-               }
-
-               instr_ptr += ret;
-               
-               instr->src_operand.type = REG_OPERAND;
-               instr->src_operand.size = operand_width;
-               decode_cr(core, reg_code, &(instr->src_operand));
 
-               instr->num_operands = 2;
-               break;
-           }
-           case STOS:
-           case STOS_8: {
-               instr->is_str_op = 1;
-               
-               if (instr->prefixes.rep == 1) {
-                   instr->str_op_length = MASK(core->vm_regs.rcx, operand_width);
-               } else {
-                   instr->str_op_length = 1;
-               }
-               
-               instr->src_operand.size = operand_width;
-               instr->src_operand.type = REG_OPERAND;
-               instr->src_operand.operand = (addr_t)&(core->vm_regs.rax);
+           instr_ptr += ret;
+           
+           instr->src_operand.type = REG_OPERAND;
+           instr->src_operand.size = operand_width;
+           decode_cr(core, reg_code, &(instr->src_operand));
 
-               instr->dst_operand.type = MEM_OPERAND;
-               instr->dst_operand.size = operand_width;
-               instr->dst_operand.operand = get_addr_linear(core, MASK(core->vm_regs.rdi, addr_width), &(core->segments.es));
+           instr->src_operand.read = 1;
+           instr->dst_operand.write = 1;
 
-               instr->num_operands = 2;
+           instr->num_operands = 2;
+           break;
+       }
+       case STOS:
+       case STOS_8: {
+           instr->is_str_op = 1;
 
-               break;
+           if (instr->prefixes.rep == 1) {
+               instr->str_op_length = MASK(core->vm_regs.rcx, operand_width);
+           } else {
+               instr->str_op_length = 1;
            }
-           case INVLPG: {
-               uint8_t reg_code = 0;
-
-               // We use the dst operand here to maintain bug-for-bug compatibility with XED
 
-               instr->dst_operand.size = operand_width;
-
-               ret = decode_rm_operand(core, instr_ptr, instr, &(instr->dst_operand), &reg_code);
+           instr->src_operand.size = operand_width;
+           instr->src_operand.type = REG_OPERAND;
+           instr->src_operand.operand = (addr_t)&(core->vm_regs.rax);
 
-               if (ret == -1) {
-                   PrintError("Error decoding operand for (%s)\n", op_form_to_str(form));
-                   return -1;
-               }
+           instr->dst_operand.type = MEM_OPERAND;
+           instr->dst_operand.size = operand_width;
+           instr->dst_operand.operand = get_addr_linear(core, MASK(core->vm_regs.rdi, addr_width), &(core->segments.es));
 
-               instr_ptr += ret;
+           instr->src_operand.read = 1;
+           instr->dst_operand.write = 1;
 
-               instr->num_operands = 1;
-               break;
-           }
-           case CLTS: {
-               // no operands. 
-               break;
+           instr->num_operands = 2;
 
+           break;
+       }
+       case INVLPG: {
+           uint8_t reg_code = 0;
+           
+           ret = decode_rm_operand(core, instr_ptr, form, instr, &(instr->dst_operand), &reg_code);
+           
+           if (ret == -1) {
+               PrintError("Error decoding operand for (%s)\n", op_form_to_str(form));
+               return -1;
            }
+           
+           instr_ptr += ret;
+           
+           instr->num_operands = 1;
+           break;
+       }
+       case CLTS: {
+           // no operands. 
+           break;
+           
        }
        default:
            PrintError("Invalid Instruction form: %s\n", op_form_to_str(form));
Public Palacios Development Repository for the V3VEE Project