processor.java

JPC: x86 PC Hardware Emulator. 牛津大学开发的一个纯JAVA的x86系统结构硬件模拟器。

				}
			    } else {
				int tssStackAddress = (targetSegment.getDPL() * 4) + 2;
				if ((tssStackAddress + 4) > tss.getLimit())
				    throw new ProcessorException(PROC_EXCEPTION_TS, tss.getSelector(), true);
				newStackSelector = 0xffff & tss.getWord(tssStackAddress + 2);
				newESP = 0xffff & tss.getWord(tssStackAddress);
			    }

			    Segment newStackSegment = null;
			    try {
				newStackSegment = getSegment(newStackSelector);
			    } catch (ProcessorException e) {
				throw new ProcessorException(PROC_EXCEPTION_TS, newStackSelector, true);
			    }

			    if (newStackSegment.getRPL() != targetSegment.getDPL())
				throw new ProcessorException(PROC_EXCEPTION_TS, newStackSelector, true);

			    if ((newStackSegment.getDPL() !=  targetSegment.getDPL()) || ((newStackSegment.getType() & 0x1a) != 0x12))
				throw new ProcessorException(PROC_EXCEPTION_TS, newStackSelector, true);

			    if (!(newStackSegment.isPresent()))
				throw new ProcessorException(PROC_EXCEPTION_SS, newStackSelector, true);

			    if (hasErrorCode) {
				if ((newStackSegment.getDefaultSizeFlag() && (esp < 24) && (esp > 0)) ||
				    !newStackSegment.getDefaultSizeFlag() && ((esp & 0xffff) < 24) && ((esp & 0xffff) > 0))
				    throw new ProcessorException(PROC_EXCEPTION_SS, 0, true);
			    } else {
				if ((newStackSegment.getDefaultSizeFlag() && (esp < 20) && (esp > 0)) ||
				    !newStackSegment.getDefaultSizeFlag() && ((esp & 0xffff) < 20) && ((esp & 0xffff) > 0))
				    throw new ProcessorException(PROC_EXCEPTION_SS, 0, true);
			    }

			    int targetOffset = interruptGate.getTargetOffset();
			    targetSegment.checkAddress(targetOffset);

			    int oldSS = ss.getSelector();
			    int oldESP = esp;
			    int oldCS = cs.getSelector();
			    int oldEIP = eip;
			    ss = newStackSegment;
			    esp = newESP;

			    cs = targetSegment;
			    eip = targetOffset;
			    setCPL(cs.getDPL());

			    if (ss.getDefaultSizeFlag()) {
				esp -= 4;
				ss.setDoubleWord(esp, oldSS);
				esp -= 4;
				ss.setDoubleWord(esp, oldESP);
				esp -= 4;
				ss.setDoubleWord(esp, getEFlags());
				esp -= 4;
				ss.setDoubleWord(esp, oldCS);
				esp -= 4;
				ss.setDoubleWord(esp, oldEIP);
				if (hasErrorCode) {
				    esp -= 4;
				    ss.setDoubleWord(esp, errorCode);
				}
			    } else {
				esp = (esp & ~0xffff) | ((esp - 4) & 0xffff);
				ss.setDoubleWord(esp & 0xffff, oldSS);
				esp = (esp & ~0xffff) | ((esp - 4) & 0xffff);
				ss.setDoubleWord(esp & 0xffff, oldESP);
				esp = (esp & ~0xffff) | ((esp - 4) & 0xffff);
				ss.setDoubleWord(esp & 0xffff, getEFlags());
				esp = (esp & ~0xffff) | ((esp - 4) & 0xffff);
				ss.setDoubleWord(esp & 0xffff, oldCS);
				esp = (esp & ~0xffff) | ((esp - 4) & 0xffff);
				ss.setDoubleWord(esp & 0xffff, oldEIP);
				if (hasErrorCode) {
				    esp = (esp & ~ 0xffff) | ((esp - 4) & 0xffff);
				    ss.setDoubleWord(esp & 0xffff, errorCode);
				}
			    }
			    
			    
			    eflagsInterruptEnable = eflagsInterruptEnableSoon = false;
			    
			    eflagsTrap = false;
			    eflagsNestedTask = false;
			    eflagsVirtual8086Mode = false;
			    eflagsResume = false;
			} else if (targetSegment.getDPL() == currentPrivilegeLevel) {
			    //SAME-PRIVILEGE
			    //check there is room on stack
			    if (hasErrorCode) {
				if ((ss.getDefaultSizeFlag() && (esp < 16) && (esp > 0)) ||
				    !ss.getDefaultSizeFlag() && ((esp & 0xffff) < 16) && ((esp & 0xffff) > 0))
				    throw new ProcessorException(PROC_EXCEPTION_SS, 0, true);
			    } else {
				if ((ss.getDefaultSizeFlag() && (esp < 12) && (esp > 0)) ||
				    !ss.getDefaultSizeFlag() && ((esp & 0xffff) < 12) && ((esp & 0xffff) > 0))
				    throw new ProcessorException(PROC_EXCEPTION_SS, 0, true);
			    }
			    
			    int targetOffset = interruptGate.getTargetOffset();
			    targetSegment.checkAddress(targetOffset);
			    

			    if (ss.getDefaultSizeFlag()) {
				esp -= 4;
				ss.setDoubleWord(esp, getEFlags());
				esp -= 4;
				ss.setDoubleWord(esp, cs.getSelector());
				esp -= 4;
				ss.setDoubleWord(esp, eip);
				if (hasErrorCode) {
				    esp -= 4;
				    ss.setDoubleWord(esp, errorCode);
				}
			    } else {
				esp = (esp & ~ 0xffff) | ((esp - 4) & 0xffff);
				ss.setDoubleWord(esp & 0xffff, getEFlags());
				esp = (esp & ~ 0xffff) | ((esp - 4) & 0xffff);
				ss.setDoubleWord(esp & 0xffff, cs.getSelector());
				esp = (esp & ~ 0xffff) | ((esp - 4) & 0xffff);
				ss.setDoubleWord(esp & 0xffff, eip);
				if (hasErrorCode) {
				    esp = (esp & ~ 0xffff) | ((esp - 4) & 0xffff);
				    ss.setDoubleWord(esp & 0xffff, errorCode);
				}
			    }

			    cs = targetSegment;
			    eip = targetOffset;

                            cs.setRPL(currentPrivilegeLevel);
			    eflagsInterruptEnable = eflagsInterruptEnableSoon = false;

			    eflagsTrap = false;
			    eflagsNestedTask = false;
			    eflagsVirtual8086Mode = false;
			    eflagsResume = false;
			} else {
			    throw new ProcessorException(PROC_EXCEPTION_GP, targetSegmentSelector + EXT, true); 
			}
		    }
		    break;
		case 0x1c: //Code: Execute-Only, Conforming
		case 0x1d: //Code: Execute-Only, Conforming, Accessed
		case 0x1e: //Code: Execute/Read, Conforming
		case 0x1f: //Code: Execute/Read, Conforming, Accessed
		    {
			if (!targetSegment.isPresent())
			    throw new ProcessorException(PROC_EXCEPTION_NP, selector, true);
			
			//SAME-PRIVILEGE
			//check there is room on stack
			if (hasErrorCode) {
			    if ((ss.getDefaultSizeFlag() && (esp < 16) && (esp > 0)) ||
				!ss.getDefaultSizeFlag() && ((esp & 0xffff) < 16) && ((esp & 0xffff) > 0))
				throw new ProcessorException(PROC_EXCEPTION_SS, 0, true);
			} else {
			    if ((ss.getDefaultSizeFlag() && (esp < 12) && (esp > 0)) ||
				!ss.getDefaultSizeFlag() && ((esp & 0xffff) < 12) && ((esp & 0xffff) > 0))
				throw new ProcessorException(PROC_EXCEPTION_SS, 0, true);
			}
			
			int targetOffset = interruptGate.getTargetOffset();
			
			targetSegment.checkAddress(targetOffset);
			
			if (ss.getDefaultSizeFlag()) {
			    esp -= 4;
			    ss.setDoubleWord(esp, getEFlags());
			    esp -= 4;
			    ss.setDoubleWord(esp, cs.getSelector());
			    esp -= 4;
			    ss.setDoubleWord(esp, eip);
			    if (hasErrorCode) {
				esp -= 4;
				ss.setDoubleWord(esp, errorCode);
			    }
			} else {
			    esp = (esp & ~ 0xffff) | ((esp - 4) & 0xffff);
			    ss.setDoubleWord(esp & 0xffff, getEFlags());
			    esp = (esp & ~ 0xffff) | ((esp - 4) & 0xffff);
			    ss.setDoubleWord(esp & 0xffff, cs.getSelector());
			    esp = (esp & ~ 0xffff) | ((esp - 4) & 0xffff);
			    ss.setDoubleWord(esp & 0xffff, eip);
			    if (hasErrorCode) {
				esp = (esp & ~ 0xffff) | ((esp - 4) & 0xffff);
				ss.setDoubleWord(esp & 0xffff, errorCode);
			    }
			}
			
			cs = targetSegment;
			eip = targetOffset;

                        cs.setRPL(currentPrivilegeLevel);

			eflagsInterruptEnable = eflagsInterruptEnableSoon = false;
			eflagsTrap = false;
			eflagsNestedTask = false;
			eflagsVirtual8086Mode = false;
			eflagsResume = false;
		    }
		break;
		}
	    }
	break;
	case 0x0f: //Interrupt Handler: 32-bit Trap Gate
	    {
		SegmentFactory.TrapGate32Bit trapGate = ((SegmentFactory.TrapGate32Bit)gate);
		
		checkGate(gate, selector, software);

		int targetSegmentSelector = trapGate.getTargetSegment();
		
		Segment targetSegment;
		try {
		    targetSegment = getSegment(targetSegmentSelector);
		} catch (ProcessorException e) {
		    throw new ProcessorException(PROC_EXCEPTION_GP, targetSegmentSelector + EXT, true);
		}
		
		if (targetSegment.getDPL() > currentPrivilegeLevel)
		    throw new ProcessorException(PROC_EXCEPTION_GP, targetSegmentSelector + EXT, true);
		
		switch(targetSegment.getType()) {
		default:
		    throw new ProcessorException(PROC_EXCEPTION_GP, targetSegmentSelector + EXT, true);
		    
		case 0x18: //Code, Execute-Only
		case 0x19: //Code, Execute-Only, Accessed
		case 0x1a: //Code, Execute/Read
		case 0x1b: //Code, Execute/Read, Accessed
		    {
			if (!targetSegment.isPresent())
			    throw new ProcessorException(PROC_EXCEPTION_NP, targetSegmentSelector + EXT, true);
			
			if (targetSegment.getDPL() < currentPrivilegeLevel) {
			    //INTER-PRIVILEGE-LEVEL
			    int newStackSelector = 0;
			    int newESP = 0;
			    if ((tss.getType() & 0x8) != 0) {
				int tssStackAddress = (targetSegment.getDPL() * 8) + 4;
				if ((tssStackAddress + 7) > tss.getLimit())
				    throw new ProcessorException(PROC_EXCEPTION_TS, tss.getSelector(), true);

                                isSup = linearMemory.isSupervisor();
				try 
                                {
                                    linearMemory.setSupervisor(true);
				    newStackSelector = 0xffff & tss.getWord(tssStackAddress + 4);
				    newESP = tss.getDoubleWord(tssStackAddress);
				}
                                finally 
                                {
                                    linearMemory.setSupervisor(isSup);
				}
			    } else {
				int tssStackAddress = (targetSegment.getDPL() * 4) + 2;
				if ((tssStackAddress + 4) > tss.getLimit())
				    throw new ProcessorException(PROC_EXCEPTION_TS, tss.getSelector(), true);
				newStackSelector = 0xffff & tss.getWord(tssStackAddress + 2);
				newESP = 0xffff & tss.getWord(tssStackAddress);
			    }

			    Segment newStackSegment = null;
			    try {
				newStackSegment = getSegment(newStackSelector);
			    } catch (ProcessorException e) {
				throw new ProcessorException(PROC_EXCEPTION_TS, newStackSelector, true);
			    }

			    if (newStackSegment.getRPL() != targetSegment.getDPL())
				throw new ProcessorException(PROC_EXCEPTION_TS, newStackSelector, true);

			    if ((newStackSegment.getDPL() !=  targetSegment.getDPL()) || ((newStackSegment.getType() & 0x1a) != 0x12))
				throw new ProcessorException(PROC_EXCEPTION_TS, newStackSelector, true);

			    if (!(newStackSegment.isPresent()))
				throw new ProcessorException(PROC_EXCEPTION_SS, newStackSelector, true);

			    if (hasErrorCode) {
				if ((newStackSegment.getDefaultSizeFlag() && (esp < 24) && (esp > 0)) ||
				    !newStackSegment.getDefaultSizeFlag() && ((esp & 0xffff) < 24) && ((esp & 0xffff) > 0))
				    throw new ProcessorException(PROC_EXCEPTION_SS, 0, true);
			    } else {
				if ((newStackSegment.getDefaultSizeFlag() && (esp < 20) && (esp > 0)) ||
				    !newStackSegment.getDefaultSizeFlag() && ((esp & 0xffff) < 20) && ((esp & 0xffff) > 0))
				    throw new ProcessorException(PROC_EXCEPTION_SS, 0, true);
			    }

			    int targetOffset = trapGate.getTargetOffset();
			    targetSegment.checkAddress(targetOffset);

			    int oldSS = ss.getSelector();
			    int oldESP = esp;
			    int oldCS = cs.getSelector();
			    int oldEIP = eip;

			    ss = newStackSegment;
			    esp = newESP;

			    cs = targetSegment;
			    eip = targetOffset;
			    setCPL(cs.getDPL());

			    if (ss.getDefaultSizeFlag()) {
				esp -= 4;
				ss.setDoubleWord(esp, oldSS);
				esp -= 4;
				ss.setDoubleWord(esp, oldESP);
				esp -= 4;
				ss.setDoubleWord(esp, getEFlags());
				esp -= 4;
				ss.setDoubleWord(esp, oldCS);
				esp -= 4;
				ss.setDoubleWord(esp, oldEIP);
				if (hasErrorCode) {
				    esp -= 4;
				    ss.setDoubleWord(esp, errorCode);
				}
			    } else {
				esp = (esp & ~0xffff) | ((esp - 4) & 0xffff);
				ss.setDoubleWord(esp & 0xffff, oldSS);
				esp = (esp & ~0xffff) | ((esp - 4) & 0xffff);
				ss.setDoubleWord(esp & 0xffff, oldESP);
				esp = (esp & ~0xffff) | ((esp - 4) & 0xffff);
				ss.setDoubleWord(esp & 0xffff, getEFlags());
				esp = (esp & ~0xffff) | ((esp - 4) & 0xffff);
				ss.setDoubleWord(esp & 0xffff, oldCS);
				esp = (esp & ~0xffff) | ((esp - 4) & 0xffff);
				ss.setDoubleWord(esp & 0xffff, oldEIP);
				if (hasErrorCode) {
				    esp = (esp & ~ 0xffff) | ((esp - 4) & 0xffff);
				    ss.setDoubleWord(esp & 0xffff, errorCode);
				}
			    }
			    
			    eflagsTrap = false;
			    eflagsNestedTask = false;
			    eflagsVirtual8086Mode = false;
			    eflagsResume = false;
			} else if (targetSegment.getDPL() == currentPrivilegeLevel) {
			    //SAME-PRIVILEGE
			    //check there is room on stack
			    if (hasErrorCode) {
				if ((ss.getDefaultSizeFlag() && (esp < 16) && (esp > 0)) ||
				    !ss.getDefaultSizeFlag() && ((esp & 0xffff) < 16) && ((esp & 0xffff) > 0))
				    throw new ProcessorException(PROC_EXCEPTION_SS, 0, true);
			    } else {
				if ((ss.getDefaultSizeFlag() && (esp < 12) && (esp > 0)) ||
				    !ss.getDefaultSizeFlag() && ((esp & 0xffff) < 12) && ((esp & 0xffff) > 0))
				    throw new ProcessorException(PROC_EXCEPTION_SS, 0, true);
			    }

			    int targetOffset = trapGate.getTargetOffset();
			    
			    targetSegment.checkAddress(targetOffset);
			    
			    if (ss.getDefaultSizeFlag()) {
				esp -= 4;
				ss.setDoubleWord(esp, getEFlags());
				esp -= 4;
				ss.setDoubleWord(esp, cs.getSelector());
				esp -= 4;
				ss.setDoubleWord(esp, eip);
				if (hasErrorCode) {
				    esp -= 4;
				    ss.setDoubleWord(esp, errorCode);
				}
			    } else {
				esp = (esp & ~ 0xffff) | ((esp - 4) & 0xffff);
				ss.setDoubleWord(esp & 0xffff, getEFlags());
				esp = (esp & ~ 0xffff) | ((esp - 4) & 0xffff);
				ss.setDoubleWord(esp & 0xffff, cs.getSelector());
				esp = (esp & ~ 0xffff) | ((esp - 4) & 0xffff);
				ss.setDoubleWord(esp & 0xffff, eip);
				if (hasErrorCode) {
				    esp = (esp & ~ 0xffff) | ((esp - 4) & 0xffff);
				    ss.setDoubleWord(esp & 0xffff, errorCode);
				}
			    }
			    
			    cs = targetSegment;
			    eip = targetOffset;

                            cs.setRPL(currentPrivilegeLevel);