/* * 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 * Copyright (c) 2008, The V3VEE Project * All rights reserved. * * Author: Jack Lange * * This is free software. You are permitted to use, * redistribute, and modify it as specified in the file "V3VEE_LICENSE". */ static int PanicUnhandledVMExit(struct VM *vm) { PrintInfo("Panicking due to VMExit with reason %u\n", vm->vmcs.exitInfoFields.reason); PrintTrace("Panicking due to VMExit with reason %u\n", vm->vmcs.exitInfoFields.reason); PrintTrace_VMCS_ALL(); PrintTrace_VMX_Regs(&(vm->registers)); VMXPanic(); return 0; } static int HandleVMPrintsAndPanics(struct VM *vm, uint_t port, uint_t data) { if (port==VMXASSIST_INFO_PORT && (vm->state == VM_VMXASSIST_STARTUP || vm->state == VM_VMXASSIST_V8086_BIOS || vm->state == VM_VMXASSIST_V8086)) { // Communication channel from VMXAssist PrintTrace("VMXASSIST Output Port\n"); PrintDebug("%c",data&0xff); return 1; } if ((port==ROMBIOS_PANIC_PORT || port==ROMBIOS_PANIC_PORT2 || port==ROMBIOS_DEBUG_PORT || port==ROMBIOS_INFO_PORT) && (vm->state==VM_VMXASSIST_V8086_BIOS)) { // rombios is communicating PrintTrace("ROMBIOS Output Port\n"); // PrintDebug("%c",data&0xff); return 1; } if (port==BOOT_STATE_CARD_PORT && vm->state==VM_VMXASSIST_V8086_BIOS) { // rombios is sending something to the display card PrintTrace("Hex Display: 0x%x\n",data&0xff); return 1; } return 0; } static int HandleInOutExit(struct VM *vm) { uint_t address; struct VMCSExitInfoFields *exitinfo = &(vm->vmcs.exitInfoFields); struct VMExitIOQual * qual = (struct VMExitIOQual *)&(vm->vmcs.exitInfoFields.qualification); struct VMXRegs *regs = &(vm->registers); address=GetLinearIP(vm); PrintTrace("Handling Input/Output Instruction Exit\n"); PrintTrace_VMX_Regs(regs); PrintTrace("Qualifications=0x%x\n", exitinfo->qualification); PrintTrace("Reason=0x%x\n", exitinfo->reason); PrintTrace("IO Port: 0x%x (%d)\n", qual->port, qual->port); PrintTrace("Instruction Info=%x\n", exitinfo->instrInfo); PrintTrace("%x : %s %s %s instruction of length %d for %d bytes from/to port 0x%x\n", address, qual->dir == 0 ? "output" : "input", qual->string ==0 ? "nonstring" : "STRING", qual->REP == 0 ? "with no rep" : "WITH REP", exitinfo->instrLength, qual->accessSize==0 ? 1 : qual->accessSize==1 ? 2 : 4, qual->port); if ((qual->port == PIC_MASTER_CMD_ISR_PORT) || (qual->port == PIC_MASTER_IMR_PORT) || (qual->port == PIC_SLAVE_CMD_ISR_PORT) || (qual->port == PIC_SLAVE_IMR_PORT)) { PrintTrace( "PIC Access\n"); } if ((qual->dir == 1) && (qual->REP == 0) && (qual->string == 0)) { char byte = In_Byte(qual->port); vm->vmcs.guestStateArea.rip += exitinfo->instrLength; regs->eax = (regs->eax & 0xffffff00) | byte; PrintTrace("Returning 0x%x in eax\n", (regs->eax)); } if (qual->dir==0 && qual->REP==0 && qual->string==0) { // See if we need to handle the outb as a signal or // print from the VM if (HandleVMPrintsAndPanics(vm,qual->port,regs->eax)) { } else { // If not, just go ahead and do the outb Out_Byte(qual->port,regs->eax); PrintTrace("Wrote 0x%x to port\n",(regs->eax)); } vm->vmcs.guestStateArea.rip += exitinfo->instrLength; } return 0; } static int HandleExternalIRQExit(struct VM *vm) { struct VMCSExitInfoFields * exitinfo = &(vm->vmcs.exitInfoFields); struct VMExitIntInfo * intInfo = (struct VMExitIntInfo *)&(vm->vmcs.exitInfoFields.intInfo); PrintTrace("External Interrupt captured\n"); PrintTrace("IntInfo: %x\n", exitinfo->intInfo); if (!intInfo->valid) { // interrupts are off, but this interrupt is not acknoledged (still pending) // so we turn on interrupts to deliver appropriately in the // host PrintTrace("External Interrupt is invald. Turning Interrupts back on\n"); asm("sti"); return 0; } // At this point, interrupts are off and the interrupt has been // acknowledged. We will now handle the interrupt ourselves // and turn interrupts back on in the host PrintTrace("type: %d\n", intInfo->type); PrintTrace("number: %d\n", intInfo->nr); PrintTrace("Interrupt %d occuring now and handled by HandleExternalIRQExit\n",intInfo->nr); switch (intInfo->type) { case 0: { // ext. IRQ // In the following, we construct an "int x" instruction // where x is the specific interrupt number that is raised // then we execute that instruciton // because we are in host context, that means it is delivered as normal // through the host IDT ((char*)(&&ext_int_seq_start))[1] = intInfo->nr; PrintTrace("Interrupt instruction setup done %x\n", *((ushort_t *)(&&ext_int_seq_start))); ext_int_seq_start: asm("int $0"); } break; case 2: // NMI PrintTrace("Type: NMI\n"); break; case 3: // hw exception PrintTrace("Type: HW Exception\n"); break; case 4: // sw exception PrintTrace("Type: SW Exception\n"); break; default: PrintTrace("Invalid Interrupt Type\n"); return -1; } if (intInfo->valid && intInfo->errorCode) { PrintTrace("IntError: %x\n", exitinfo->intErrorCode); } return 0; } static int HandleExceptionOrNMI(struct VM *vm) { struct Instruction inst; uint_t num; uint_t type; uint_t errorvalid; uint_t error; uint_t ext=0; uint_t idt=0; uint_t ti=0; uint_t selectorindex=0; PrintTrace("Exception or NMI occurred\n"); num=vm->vmcs.exitInfoFields.intInfo & 0xff; type=(vm->vmcs.exitInfoFields.intInfo & 0x700)>>8; errorvalid=(vm->vmcs.exitInfoFields.intInfo & 0x800)>>11; if (errorvalid) { error=vm->vmcs.exitInfoFields.intErrorCode; ext=error&0x1; idt=(error&0x2)>>1; ti=(error&0x4)>>2; selectorindex=(error>>3)&0xffff; } PrintTrace("Exception %d now - handled by HandleExceptionOrNMI\n",num); PrintTrace("Exception Number %u : %s\n", num, exception_names[num]); PrintTrace("Exception Type %u : %s\n", type, exception_type_names[type]); if (errorvalid) { if (ext) { PrintTrace("External\n"); } else { PrintTrace("%s - Selector Index is %u\n", idt ? "IDT" : ti ? "LDT" : "GDT", selectorindex); } } DecodeCurrentInstruction(vm,&inst); if (inst.type==VM_MOV_TO_CR0) { PrintTrace("MOV TO CR0, oldvalue=0x%x, newvalue=0x%x\n",inst.input2, inst.input1); if ((inst.input2 & CR0_PE) && !(inst.input1 & CR0_PE) && vm->state==VM_VMXASSIST_STARTUP) { // This is VMXAssist signalling for us to turn on V8086 mode and // jump into the bios PrintTrace("VMXAssist is signaling us for switch to V8086 mode and jump to 0xf000:fff0\n"); SetupV8086ModeForBoot(vm); goto leave; } else { PrintTrace("Instruction is a write to CR0, but we don't understand it so we'll just exec it\n"); } } PrintTrace("Trying to execute the faulting instruction in VMM context now\n"); ExecFaultingInstructionInVMM(vm); leave: // //PanicUnhandledVMExit(vmcs,regs); //VMXPanic(); return 0; } int Do_VMM(struct VMXRegs regs) { ullong_t vmcs_ptr = 0; uint_t vmcs_ptr_low = 0; int ret = 0; uint_t vmx_abort = 0; PrintTrace("Vm Exit\n"); ret = VMCS_STORE(&vmcs_ptr); vmcs_ptr &= 0xffffffff; vmcs_ptr_low += vmcs_ptr; PrintTrace("ret=%d\n", ret); PrintTrace("Revision: %x\n", *(uint_t *)(vmcs_ptr_low)); vmx_abort = *(uint_t*)(((char *)vmcs_ptr_low)+4); struct VM *vm = FindVM(); if (vmx_abort != 0) { PrintTrace("VM ABORTED w/ code: %x\n", vmx_abort); return -1; } vm->registers = regs; if (CopyOutVMCSData(&(vm->vmcs)) != 0) { PrintTrace("Could not copy out VMCS\n"); return -1; } PrintTrace("Guest esp: 0x%x (%u)\n", vm->vmcs.guestStateArea.rsp, vm->vmcs.guestStateArea.rsp); PrintTrace("VM Exit for reason: %d (%x)\n", vm->vmcs.exitInfoFields.reason & 0x00000fff, vm->vmcs.exitInfoFields.reason); if (vm->vmcs.exitInfoFields.reason & (0x1<<29) ) { PrintTrace("VM Exit is from VMX root operation. Panicking\n"); VMXPanic(); } if (vm->vmcs.exitInfoFields.reason & (0x1<<31) ) { PrintTrace("VM Exit is due to a VM entry failure. Shouldn't happen here. Panicking\n"); PrintTrace_VMCSData(&(vm->vmcs)); VMXPanic(); } switch (vm->vmcs.exitInfoFields.reason) { case VM_EXIT_REASON_INFO_EXCEPTION_OR_NMI: ret = HandleExceptionOrNMI(vm); break; case VM_EXIT_REASON_EXTERNAL_INTR: ret = HandleExternalIRQExit(vm); break; case VM_EXIT_REASON_TRIPLE_FAULT: ret = PanicUnhandledVMExit(vm); break; case VM_EXIT_REASON_INIT_SIGNAL: ret = PanicUnhandledVMExit(vm); break; case VM_EXIT_REASON_STARTUP_IPI: ret = PanicUnhandledVMExit(vm); break; case VM_EXIT_REASON_IO_SMI: ret = PanicUnhandledVMExit(vm); break; case VM_EXIT_REASON_OTHER_SMI: ret = PanicUnhandledVMExit(vm); break; case VM_EXIT_REASON_INTR_WINDOW: ret = PanicUnhandledVMExit(vm); break; case VM_EXIT_REASON_NMI_WINDOW: ret = PanicUnhandledVMExit(vm); break; case VM_EXIT_REASON_TASK_SWITCH: ret = PanicUnhandledVMExit(vm); break; case VM_EXIT_REASON_CPUID: ret = PanicUnhandledVMExit(vm); break; case VM_EXIT_REASON_INVD: ret = PanicUnhandledVMExit(vm); break; case VM_EXIT_REASON_INVLPG: ret = PanicUnhandledVMExit(vm); break; case VM_EXIT_REASON_RDPMC: ret = PanicUnhandledVMExit(vm); break; case VM_EXIT_REASON_RDTSC: ret = PanicUnhandledVMExit(vm); break; case VM_EXIT_REASON_RSM: ret = PanicUnhandledVMExit(vm); break; case VM_EXIT_REASON_VMCALL: ret = PanicUnhandledVMExit(vm); break; case VM_EXIT_REASON_VMCLEAR: ret = PanicUnhandledVMExit(vm); break; case VM_EXIT_REASON_VMLAUNCH: ret = PanicUnhandledVMExit(vm); break; case VM_EXIT_REASON_VMPTRLD: ret = PanicUnhandledVMExit(vm); break; case VM_EXIT_REASON_VMPTRST: ret = PanicUnhandledVMExit(vm); break; case VM_EXIT_REASON_VMREAD: ret = PanicUnhandledVMExit(vm); break; case VM_EXIT_REASON_VMRESUME: ret = PanicUnhandledVMExit(vm); break; case VM_EXIT_REASON_VMWRITE: ret = PanicUnhandledVMExit(vm); break; case VM_EXIT_REASON_VMXOFF: ret = PanicUnhandledVMExit(vm); break; case VM_EXIT_REASON_VMXON: ret = PanicUnhandledVMExit(vm); break; case VM_EXIT_REASON_CR_REG_ACCESSES: ret = PanicUnhandledVMExit(vm); break; case VM_EXIT_REASON_MOV_DR: ret = PanicUnhandledVMExit(vm); break; case VM_EXIT_REASON_IO_INSTR: ret = HandleInOutExit(vm); break; case VM_EXIT_REASON_RDMSR: ret = PanicUnhandledVMExit(vm); break; case VM_EXIT_REASON_WRMSR: ret = PanicUnhandledVMExit(vm); break; case VM_EXIT_REASON_ENTRY_FAIL_INVALID_GUEST_STATE: ret = PanicUnhandledVMExit(vm); break; case VM_EXIT_REASON_ENTRY_FAIL_MSR_LOAD: ret = PanicUnhandledVMExit(vm); break; case VM_EXIT_REASON_MWAIT: ret = PanicUnhandledVMExit(vm); break; case VM_EXIT_REASON_MONITOR: ret = PanicUnhandledVMExit(vm); break; case VM_EXIT_REASON_PAUSE: ret = PanicUnhandledVMExit(vm); break; case VM_EXIT_REASON_ENTRY_FAILURE_MACHINE_CHECK: ret = PanicUnhandledVMExit(vm); break; case VM_EXIT_REASON_TPR_BELOW_THRESHOLD: ret = PanicUnhandledVMExit(vm); break; default: ret = PanicUnhandledVMExit(vm); break; } regs = vm->registers; CopyInVMCSData(&(vm->vmcs)); /* { VMCS_CLEAR(vmcs_ptr); } */ PrintTrace("Returning from Do_VMM: %d\n", ret); return ret; } // simply execute the instruction that is faulting and return static int ExecFaultingInstructionInVMM(struct VM *vm) { uint_t address = GetLinearIP(vm); myregs = (uint_t)&(vm->registers); PrintTrace("About the execute faulting instruction!\n"); PrintTrace("Instruction is:\n"); PrintTraceMemDump((void*)(address),vm->vmcs.exitInfoFields.instrLength); PrintTrace("The template code is:\n"); PrintTraceMemDump(&&template_code,TEMPLATE_CODE_LEN); // clone the template code //memcpy(&&template_code,code,MAX_CODE); // clean up the nop field memset(&&template_code+INSTR_OFFSET_START,*((uchar_t *)(&&template_code+0)),NOP_SEQ_LEN); // overwrite the nops with the faulting instruction memcpy(&&template_code+INSTR_OFFSET_START, (void*)(address),vm->vmcs.exitInfoFields.instrLength); PrintTrace("Finished modifying the template code, which now is:\n"); PrintTraceMemDump(&&template_code,TEMPLATE_CODE_LEN); PrintTrace("Now entering modified template code\n"); template_code: // Template code stores current registers, // restores registers, has a landing pad of noops // that will be modified, restores current regs, and then returns // // Note that this currently ignores cr0, cr3, cr4, dr7, rsp, rip, and rflags // it also blythly assumes it can exec the instruction in protected mode // __asm__ __volatile__ ("nop\n" // for cloning purposes (1 byte) "pusha\n" // push our current regs onto the current stack (1 byte) "movl %0, %%eax\n" // Get oldesp location (5 bytes) "movl %%esp, (%%eax)\n" // store the current stack pointer in oldesp (2 bytes) "movl %1, %%eax\n" // Get regs location (5 bytes) "movl (%%eax), %%esp\n" // point esp at regs (2 bytes) "popa\n" // now we have the VM registers restored (1 byte) "nop\n" // now we execute the actual instruction (1 byte x 10) "nop\n" // now we execute the actual instruction "nop\n" // now we execute the actual instruction "nop\n" // now we execute the actual instruction "nop\n" // now we execute the actual instruction "nop\n" // now we execute the actual instruction "nop\n" // now we execute the actual instruction "nop\n" // now we execute the actual instruction "nop\n" // now we execute the actual instruction "nop\n" // now we execute the actual instruction // need to copy back to the VM registers! "movl %0, %%eax\n" // recapture oldesp location (5 bytes) "movl (%%eax), %%esp\n" // now we'll get our esp back from oldesp (2 bytes) "popa\n" // and restore our GP regs and we're done (1 byte) : "=m"(oldesp) : "m"(myregs) ); PrintTrace("Survived executing the faulting instruction and returning.\n"); vm->vmcs.guestStateArea.rip += vm->vmcs.exitInfoFields.instrLength; return 0; }