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#include <string.h>
#include <stdarg.h>
#include <signal.h>
#include <setjmp.h>
#include <minix/config.h>
#include <minix/const.h>
#include <minix/ipc.h>
#include <minix/com.h>
#include <minix/syslib.h>
#include <machine/stackframe.h>
#include "vassert.h"
VAssert_StateWrapper vassert_state ALIGNED(VASSERT_PAGE_SIZE);
#define TRUE 1
#define FALSE 0
#define MAGIC_CMD 0x564d5868
#define MAGIC_PORT 0x5658
#define HIGH_BAND_PORT 0x5659
#define BACKDOOR_PORT 51
#define BACKDOOR_HB_PORT 1
#define CMD_SET_ADDRESS BACKDOOR_PORT|(1<<16)
#define CMD_RETURN_REPLAY BACKDOOR_PORT|(2<<16)
#define CMD_GO_LIVE BACKDOOR_PORT|(3<<16)
#define CMD_LOG BACKDOOR_HB_PORT|(4<<16)
#define CMD_SET_RECORD 47
#define LOG_MAX 512
typedef char Bool;
typedef unsigned int uint32;
typedef unsigned long long uint64;
#ifdef VM_X86_64
typedef uint64 VA;
#else
typedef uint32 VA;
#endif
static sigjmp_buf segv_jmp;
void libvassert_process_backdoor(uint32, uint32, uint32, reg_t *, reg_t *,
reg_t *, reg_t *);
/*
*---------------------------------------------------------------------
*
* sig_segv --
*
* Customed SEGV signal handler for VAssert_IsInVM.
*
* Results:
*
* None.
*
* Side effects:
* None.
*
*---------------------------------------------------------------------
*/
static void __dead sig_segv(int sig_no)
{
/* jumping to error handling in VAssert_IsInVM. */
siglongjmp(segv_jmp, 1);
}
/*
*---------------------------------------------------------------------
*
* VAssert_IsInVM --
*
* Check if we are in virtual world.
*
* Results:
*
* Return TRUE on success, or FALSE on failure.
*
* Side effects:
* None.
*
*---------------------------------------------------------------------
*/
static Bool VAssert_IsInVM(void)
{
uint32 eax, ebx, ecx, edx;
static Bool inVM = FALSE;
static Bool tested = FALSE;
if (!tested) {
/* Error handling. */
if (sigsetjmp(segv_jmp, 0) != 0) {
signal(SIGSEGV, SIG_DFL);
inVM = FALSE;
return inVM;
}
tested = TRUE;
/* Install custom handler. */
signal(SIGSEGV, sig_segv);
/* Test if we are in a VM. */
libvassert_process_backdoor(0x0a, 0, MAGIC_PORT, &eax, &ebx, &ecx, &edx);
signal(SIGSEGV, SIG_DFL);
inVM = TRUE;
}
return inVM;
}
/*
*---------------------------------------------------------------------
*
* VAssert_Init --
*
* Tell vmx that vassert is inited.
*
* Results:
*
* Return 0 on success, or -1 on failure.
*
* Side effects:
* None
*
*---------------------------------------------------------------------
*/
char VAssert_Init(void)
{
uint32 eax, ebx, ecx, edx;
VA page_address = (VA) &vassert_state.inReplay;
if (!VAssert_IsInVM()) {
return -1;
}
bzero((char*) &vassert_state, sizeof vassert_state);
#ifndef __minix
/* Lock the page. */
if (mlock(&vassert_state, sizeof vassert_state)) {
return -1;
}
#endif
libvassert_process_backdoor(CMD_SET_ADDRESS, page_address,
MAGIC_PORT|(1<<16), &eax, &ebx, &ecx, &edx);
return (eax != (uint32)-1) ? 0 : -1;
}
/*
*---------------------------------------------------------------------
*
* VAssert_Uninit --
*
* Tell vmx that vassert is finalized.
*
* Results:
*
* Return 0 on success, or -1 on failure.
*
* Side effects:
* None
*
*---------------------------------------------------------------------
*/
char VAssert_Uninit(void)
{
unsigned int eax, ebx, ecx, edx;
if (!VAssert_IsInVM()) {
return -1;
}
libvassert_process_backdoor(CMD_SET_ADDRESS, 0, MAGIC_PORT|(0<<16), &eax, &ebx, &ecx, &edx);
return (eax != (unsigned int)-1) ? 0 : 1;
}
/*
*---------------------------------------------------------------------
*
* VAssert_LogMain --
*
* Print message to a text file on host side.
*
* Results:
* None
*
* Side effects:
* Write to a text file with fixed name.
* If the file exists, host UI will ask for append/replace/ignore
*
*---------------------------------------------------------------------
*/
void VAssert_LogMain(const char *format, ...)
{
unsigned int eax, ebx, ecx, edx;
char buf[LOG_MAX];
unsigned int len = 0;
va_list ap;
va_start(ap, format);
len = vsnprintf(buf, LOG_MAX, format, ap);
va_end(ap);
__asm__ __volatile__("cld; rep outsb;"
: "=a"(eax), "=b"(ebx), "=c"(ecx), "=d"(edx)
: "0"(MAGIC_CMD), "1"(CMD_LOG), "2"(len), "d"(HIGH_BAND_PORT), "S"(buf)
: "memory"
);
}
/*
*---------------------------------------------------------------------
*
* VAssert_GoLiveMain --
*
* Make the vm which is in replay exit replay.
*
* Results:
* None
*
* Side effects:
* Replay is stopped.
*
*---------------------------------------------------------------------
*/
void VAssert_GoLiveMain(void)
{
unsigned int eax, ebx, ecx, edx;
vassert_state.inReplay = 0;
libvassert_process_backdoor(CMD_GO_LIVE, 0, MAGIC_PORT, &eax, &ebx, &ecx, &edx);
}
/*
*---------------------------------------------------------------------
*
* VAssert_ReturnToReplayMain --
*
* Called after the custom work is done, and replay is to continue.
*
* Results:
* None
*
* Side effects:
* Replay is continued from pause.
*
*---------------------------------------------------------------------
*/
void VAssert_ReturnToReplayMain(void)
{
unsigned int eax, ebx, ecx, edx;
libvassert_process_backdoor(CMD_RETURN_REPLAY, 0, MAGIC_PORT, &eax, &ebx, &ecx, &edx);
}
/*
*---------------------------------------------------------------------
*
* VAssert_SetRecordingMain --
*
* Ask vmx for starting or stopping recording.
*
* Results:
*
* Return TRUE on success, or FALSE on failure.
*
* Side effects:
* Recording is started or stopped.
*
*---------------------------------------------------------------------
*/
char VAssert_SetRecordingMain(char start)
{
uint32 eax, ebx, ecx, edx;
if (!VAssert_IsInVM()) {
return FALSE;
}
libvassert_process_backdoor(CMD_SET_RECORD, start ? 1 : 2, MAGIC_PORT, &eax, &ebx, &ecx, &edx);
return (eax == 1) ? TRUE : FALSE;
}
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