控制流保护技术

桃扇骨 2022-12-15 15:27 139阅读 0赞

## Control Transfer Terminating Instructions ##

### ENDBR64 — Terminate an Indirect Branch in 64-bit Mode ###

<table> 
 <thead> 
  <tr> 
   <th>Opcode</th> 
   <th>Instruction</th> 
   <th>Op/En</th> 
   <th>64-Bit Mode</th> 
   <th>Compat/Leg Mode</th> 
   <th>Description</th> 
  </tr> 
 </thead> 
 <tbody> 
  <tr> 
   <td>F3 0F 1E FA</td> 
   <td>ENDBR64</td> 
   <td>NP</td> 
   <td>Valid</td> 
   <td>Valid</td> 
   <td>Terminate indirect branch in 64 bit mode.</td> 
  </tr> 
 </tbody> 
</table>

--------------------

Instruction Operand Encoding

<table> 
 <thead> 
  <tr> 
   <th>Op/En</th> 
   <th>Operand 1</th> 
   <th>Operand 2</th> 
   <th>Operand 3</th> 
   <th>Operand 4</th> 
  </tr> 
 </thead> 
 <tbody> 
  <tr> 
   <td>NP</td> 
   <td>NA</td> 
   <td>NA</td> 
   <td>NA</td> 
   <td>NA</td> 
  </tr> 
 </tbody> 
</table>

--------------------

Description
    Terminate an indirect branch in 64 bit mode.

--------------------

Operation
    
    IF EndbranchEnabled(CPL) & EFER.LMA = 1 & CS.L = 1
    	IF CPL = 3
    	THEN
    		IA32_U_CET.TRACKER = IDLE
    		IA32_U_CET.SUPPRESS = 0
    	ELSE
    		IA32_S_CET.TRACKER = IDLE
     		IA32_S_CET.SUPPRESS = 0
    	FI
    FI;

--------------------

Flags Affected
    None.

--------------------

Exceptions
    None.

### ENDBR32 — Terminate an Indirect Branch in 64-bit Mode ###

<table> 
 <thead> 
  <tr> 
   <th>Opcode</th> 
   <th>Instruction</th> 
   <th>Op/En</th> 
   <th>64-Bit Mode</th> 
   <th>Compat/Leg Mode</th> 
   <th>Description</th> 
  </tr> 
 </thead> 
 <tbody> 
  <tr> 
   <td>F3 0F 1E FB</td> 
   <td>ENDBR32</td> 
   <td>NP</td> 
   <td>Valid</td> 
   <td>Valid</td> 
   <td>Terminate indirect branch in 32 bit mode.</td> 
  </tr> 
 </tbody> 
</table>

--------------------

Instruction Operand Encoding

--------------------

Description
    Terminate an indirect branch in 32 bit mode.

--------------------

Operation
    
    IF  EndbranchEnabled(CPL) & (EFER.LMA = 0 | (EFER.LMA=1 & CS.L = 0)
    	IF CPL = 3
    	THEN
    		IA32_U_CET.TRACKER = IDLE
    		IA32_U_CET.SUPPRESS = 0
    	ELSE
    		IA32_S_CET.TRACKER = IDLE
     		IA32_S_CET.SUPPRESS = 0
    	FI
    FI;

--------------------

Flags Affected
    None.

--------------------

Exceptions
    None.

# 参考 #

[CONTROL-FLOW ENFORCEMENT TECHNOLOGY SPECIFICATION  
][CONTROL-FLOW ENFORCEMENT TECHNOLOGY SPECIFICATION]

[CONTROL-FLOW ENFORCEMENT TECHNOLOGY SPECIFICATION]: https://software.intel.com/sites/default/files/managed/4d/2a/control-flow-enforcement-technology-preview.pdf