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|
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <stdint.h>
typedef uint8_t u8;
typedef uint16_t u16;
typedef uint32_t u32;
typedef uint64_t u64;
typedef int8_t s8;
typedef int16_t s16;
typedef int32_t s32;
typedef int64_t s64;
#include <public/xen.h>
#include <asm-x86/x86_emulate.h>
#include <sys/mman.h>
#define PFEC_write_access (1U<<1)
static int read(
unsigned int seg,
unsigned long offset,
unsigned long *val,
unsigned int bytes,
struct x86_emulate_ctxt *ctxt)
{
unsigned long addr = offset;
switch ( bytes )
{
case 1: *val = *(u8 *)addr; break;
case 2: *val = *(u16 *)addr; break;
case 4: *val = *(u32 *)addr; break;
case 8: *val = *(unsigned long *)addr; break;
}
return X86EMUL_CONTINUE;
}
static int write(
unsigned int seg,
unsigned long offset,
unsigned long val,
unsigned int bytes,
struct x86_emulate_ctxt *ctxt)
{
unsigned long addr = offset;
switch ( bytes )
{
case 1: *(u8 *)addr = (u8)val; break;
case 2: *(u16 *)addr = (u16)val; break;
case 4: *(u32 *)addr = (u32)val; break;
case 8: *(unsigned long *)addr = val; break;
}
return X86EMUL_CONTINUE;
}
static int cmpxchg(
unsigned int seg,
unsigned long offset,
unsigned long old,
unsigned long new,
unsigned int bytes,
struct x86_emulate_ctxt *ctxt)
{
unsigned long addr = offset;
switch ( bytes )
{
case 1: *(u8 *)addr = (u8)new; break;
case 2: *(u16 *)addr = (u16)new; break;
case 4: *(u32 *)addr = (u32)new; break;
case 8: *(unsigned long *)addr = new; break;
}
return X86EMUL_CONTINUE;
}
static int cmpxchg8b(
unsigned int seg,
unsigned long offset,
unsigned long old_lo,
unsigned long old_hi,
unsigned long new_lo,
unsigned long new_hi,
struct x86_emulate_ctxt *ctxt)
{
unsigned long addr = offset;
((unsigned long *)addr)[0] = new_lo;
((unsigned long *)addr)[1] = new_hi;
return X86EMUL_CONTINUE;
}
static struct x86_emulate_ops emulops = {
.read = read,
.insn_fetch = read,
.write = write,
.cmpxchg = cmpxchg,
.cmpxchg8b = cmpxchg8b
};
int main(int argc, char **argv)
{
struct x86_emulate_ctxt ctxt;
struct cpu_user_regs regs;
char instr[20] = { 0x01, 0x08 }; /* add %ecx,(%eax) */
unsigned int *res;
int rc;
ctxt.regs = ®s;
ctxt.mode = X86EMUL_MODE_PROT32;
res = mmap((void *)0x100000, 0x1000, PROT_READ|PROT_WRITE,
MAP_FIXED|MAP_PRIVATE|MAP_ANONYMOUS, 0, 0);
if ( res == MAP_FAILED )
{
fprintf(stderr, "mmap to low address failed\n");
exit(1);
}
printf("%-40s", "Testing addl %%ecx,(%%eax)...");
instr[0] = 0x01; instr[1] = 0x08;
regs.eflags = 0x200;
regs.eip = (unsigned long)&instr[0];
regs.ecx = 0x12345678;
regs.error_code = PFEC_write_access;
regs.eax = (unsigned long)res;
*res = 0x7FFFFFFF;
rc = x86_emulate_memop(&ctxt, &emulops);
if ( (rc != 0) ||
(*res != 0x92345677) ||
(regs.eflags != 0xa94) ||
(regs.eip != (unsigned long)&instr[2]) )
goto fail;
printf("okay\n");
printf("%-40s", "Testing xorl (%%eax),%%ecx...");
instr[0] = 0x33; instr[1] = 0x08;
regs.eflags = 0x200;
regs.eip = (unsigned long)&instr[0];
#ifdef __x86_64__
regs.ecx = 0xFFFFFFFF12345678UL;
#else
regs.ecx = 0x12345678UL;
#endif
regs.eax = (unsigned long)res;
regs.error_code = 0;
rc = x86_emulate_memop(&ctxt, &emulops);
if ( (rc != 0) ||
(*res != 0x92345677) ||
(regs.ecx != 0x8000000FUL) ||
(regs.eip != (unsigned long)&instr[2]) )
goto fail;
printf("okay\n");
printf("%-40s", "Testing movl (%%eax),%%ecx...");
instr[0] = 0x8b; instr[1] = 0x08;
regs.eflags = 0x200;
regs.eip = (unsigned long)&instr[0];
regs.ecx = ~0UL;
regs.eax = (unsigned long)res;
regs.error_code = 0;
rc = x86_emulate_memop(&ctxt, &emulops);
if ( (rc != 0) ||
(*res != 0x92345677) ||
(regs.ecx != 0x92345677UL) ||
(regs.eip != (unsigned long)&instr[2]) )
goto fail;
printf("okay\n");
printf("%-40s", "Testing lock cmpxchgb %%cl,(%%ebx)...");
instr[0] = 0xf0; instr[1] = 0x0f; instr[2] = 0xb0; instr[3] = 0x0b;
regs.eflags = 0x200;
regs.eip = (unsigned long)&instr[0];
regs.eax = 0x92345677UL;
regs.ecx = 0xAA;
regs.ebx = (unsigned long)res;
regs.error_code = PFEC_write_access;
rc = x86_emulate_memop(&ctxt, &emulops);
if ( (rc != 0) ||
(*res != 0x923456AA) ||
(regs.eflags != 0x244) ||
(regs.eax != 0x92345677UL) ||
(regs.eip != (unsigned long)&instr[4]) )
goto fail;
printf("okay\n");
printf("%-40s", "Testing lock cmpxchgb %%cl,(%%ebx)...");
instr[0] = 0xf0; instr[1] = 0x0f; instr[2] = 0xb0; instr[3] = 0x0b;
regs.eflags = 0x200;
regs.eip = (unsigned long)&instr[0];
regs.eax = 0xAABBCC77UL;
regs.ecx = 0xFF;
regs.ebx = (unsigned long)res;
regs.error_code = PFEC_write_access;
rc = x86_emulate_memop(&ctxt, &emulops);
if ( (rc != 0) ||
(*res != 0x923456AA) ||
((regs.eflags&0x240) != 0x200) ||
(regs.eax != 0xAABBCCAA) ||
(regs.ecx != 0xFF) ||
(regs.eip != (unsigned long)&instr[4]) )
goto fail;
printf("okay\n");
printf("%-40s", "Testing xchgl %%ecx,(%%eax)...");
instr[0] = 0x87; instr[1] = 0x08;
regs.eflags = 0x200;
regs.eip = (unsigned long)&instr[0];
regs.ecx = 0x12345678;
regs.eax = (unsigned long)res;
regs.error_code = PFEC_write_access;
rc = x86_emulate_memop(&ctxt, &emulops);
if ( (rc != 0) ||
(*res != 0x12345678) ||
(regs.eflags != 0x200) ||
(regs.ecx != 0x923456AA) ||
(regs.eip != (unsigned long)&instr[2]) )
goto fail;
printf("okay\n");
printf("%-40s", "Testing lock cmpxchgl %%ecx,(%%ebx)...");
instr[0] = 0xf0; instr[1] = 0x0f; instr[2] = 0xb1; instr[3] = 0x0b;
regs.eflags = 0x200;
*res = 0x923456AA;
regs.eip = (unsigned long)&instr[0];
regs.eax = 0x923456AAUL;
regs.ecx = 0xDDEEFF00L;
regs.ebx = (unsigned long)res;
regs.error_code = PFEC_write_access;
rc = x86_emulate_memop(&ctxt, &emulops);
if ( (rc != 0) ||
(*res != 0xDDEEFF00) ||
(regs.eflags != 0x244) ||
(regs.eax != 0x923456AAUL) ||
(regs.eip != (unsigned long)&instr[4]) )
goto fail;
printf("okay\n");
printf("%-40s", "Testing rep movsw...");
instr[0] = 0xf3; instr[1] = 0x66; instr[2] = 0xa5;
*res = 0x22334455;
regs.eflags = 0x200;
regs.ecx = 23;
regs.eip = (unsigned long)&instr[0];
regs.esi = (unsigned long)res + 0;
regs.edi = (unsigned long)res + 2;
regs.error_code = 0; /* read fault */
rc = x86_emulate_memop(&ctxt, &emulops);
if ( (rc != 0) ||
(*res != 0x44554455) ||
(regs.eflags != 0x200) ||
(regs.ecx != 22) ||
(regs.esi != ((unsigned long)res + 2)) ||
(regs.edi != ((unsigned long)res + 4)) ||
(regs.eip != (unsigned long)&instr[0]) )
goto fail;
printf("okay\n");
printf("%-40s", "Testing btrl $0x1,(%edi)...");
instr[0] = 0x0f; instr[1] = 0xba; instr[2] = 0x37; instr[3] = 0x01;
*res = 0x2233445F;
regs.eflags = 0x200;
regs.eip = (unsigned long)&instr[0];
regs.edi = (unsigned long)res;
regs.error_code = PFEC_write_access;
rc = x86_emulate_memop(&ctxt, &emulops);
if ( (rc != 0) ||
(*res != 0x2233445D) ||
((regs.eflags&0x201) != 0x201) ||
(regs.eip != (unsigned long)&instr[4]) )
goto fail;
printf("okay\n");
printf("%-40s", "Testing btrl %eax,(%edi)...");
instr[0] = 0x0f; instr[1] = 0xb3; instr[2] = 0x07;
*res = 0x2233445F;
regs.eflags = 0x200;
regs.eip = (unsigned long)&instr[0];
regs.eax = -32;
regs.edi = (unsigned long)(res+1);
regs.error_code = PFEC_write_access;
rc = x86_emulate_memop(&ctxt, &emulops);
if ( (rc != 0) ||
(*res != 0x2233445E) ||
((regs.eflags&0x201) != 0x201) ||
(regs.eip != (unsigned long)&instr[3]) )
goto fail;
printf("okay\n");
res[0] = 0x12345678;
res[1] = 0x87654321;
printf("%-40s", "Testing cmpxchg8b (%edi) [succeeding]...");
instr[0] = 0x0f; instr[1] = 0xc7; instr[2] = 0x0f;
regs.eflags = 0x200;
regs.eax = res[0];
regs.edx = res[1];
regs.ebx = 0x9999AAAA;
regs.ecx = 0xCCCCFFFF;
regs.eip = (unsigned long)&instr[0];
regs.edi = (unsigned long)res;
regs.error_code = PFEC_write_access;
rc = x86_emulate_memop(&ctxt, &emulops);
if ( (rc != 0) ||
(res[0] != 0x9999AAAA) ||
(res[1] != 0xCCCCFFFF) ||
((regs.eflags&0x240) != 0x240) ||
(regs.eip != (unsigned long)&instr[3]) )
goto fail;
printf("okay\n");
printf("%-40s", "Testing cmpxchg8b (%edi) [failing]...");
instr[0] = 0x0f; instr[1] = 0xc7; instr[2] = 0x0f;
regs.eflags = 0x200;
regs.eip = (unsigned long)&instr[0];
regs.edi = (unsigned long)res;
regs.error_code = PFEC_write_access;
rc = x86_emulate_memop(&ctxt, &emulops);
if ( (rc != 0) ||
(res[0] != 0x9999AAAA) ||
(res[1] != 0xCCCCFFFF) ||
(regs.eax != 0x9999AAAA) ||
(regs.edx != 0xCCCCFFFF) ||
((regs.eflags&0x240) != 0x200) ||
(regs.eip != (unsigned long)&instr[3]) )
goto fail;
printf("okay\n");
printf("%-40s", "Testing movsxbd (%%eax),%%ecx...");
instr[0] = 0x0f; instr[1] = 0xbe; instr[2] = 0x08;
regs.eflags = 0x200;
regs.eip = (unsigned long)&instr[0];
regs.ecx = 0x12345678;
regs.eax = (unsigned long)res;
*res = 0x82;
regs.error_code = 0;
rc = x86_emulate_memop(&ctxt, &emulops);
if ( (rc != 0) ||
(*res != 0x82) ||
(regs.ecx != 0xFFFFFF82) ||
((regs.eflags&0x240) != 0x200) ||
(regs.eip != (unsigned long)&instr[3]) )
goto fail;
printf("okay\n");
printf("%-40s", "Testing movzxwd (%%eax),%%ecx...");
instr[0] = 0x0f; instr[1] = 0xb7; instr[2] = 0x08;
regs.eflags = 0x200;
regs.eip = (unsigned long)&instr[0];
regs.ecx = 0x12345678;
regs.eax = (unsigned long)res;
*res = 0x1234aa82;
regs.error_code = 0;
rc = x86_emulate_memop(&ctxt, &emulops);
if ( (rc != 0) ||
(*res != 0x1234aa82) ||
(regs.ecx != 0xaa82) ||
((regs.eflags&0x240) != 0x200) ||
(regs.eip != (unsigned long)&instr[3]) )
goto fail;
printf("okay\n");
printf("%-40s", "Testing xadd %%ax,(%%ecx)...");
instr[0] = 0x66; instr[1] = 0x0f; instr[2] = 0xc1; instr[3] = 0x01;
regs.eflags = 0x200;
regs.eip = (unsigned long)&instr[0];
regs.ecx = (unsigned long)res;
regs.eax = 0x12345678;
*res = 0x11111111;
regs.error_code = 0;
rc = x86_emulate_memop(&ctxt, &emulops);
if ( (rc != 0) ||
(*res != 0x11116789) ||
(regs.eax != 0x12341111) ||
((regs.eflags&0x240) != 0x200) ||
(regs.eip != (unsigned long)&instr[4]) )
goto fail;
printf("okay\n");
return 0;
fail:
printf("failed!\n");
return 1;
}
|
