instrs: Force RIP access to 64-bit and fix XBEGIN

This commit is contained in:
Alexis Engelke
2020-11-22 13:10:30 +01:00
parent f9bba6289e
commit 6fe5500444
5 changed files with 76 additions and 73 deletions

View File

@@ -276,8 +276,7 @@ struct InstrDesc
#define DESC_IMPLICIT_VAL(desc) (((desc)->immediate >> 2) & 1)
#define DESC_LOCK(desc) (((desc)->immediate >> 3) & 1)
#define DESC_VSIB(desc) (((desc)->immediate >> 7) & 1)
#define DESC_SIZE8(desc) (((desc)->operand_sizes >> 8) & 1)
#define DESC_SIZED64(desc) (((desc)->operand_sizes >> 9) & 1)
#define DESC_OPSIZE(desc) (((desc)->operand_sizes >> 8) & 3)
#define DESC_SIZE_FIX1(desc) (((desc)->operand_sizes >> 10) & 7)
#define DESC_SIZE_FIX2(desc) (((desc)->operand_sizes >> 13) & 3)
#define DESC_INSTR_WIDTH(desc) (((desc)->operand_sizes >> 15) & 1)
@@ -411,27 +410,21 @@ fd_decode(const uint8_t* buffer, size_t len_sz, int mode_int, uintptr_t address,
struct InstrDesc* desc = (struct InstrDesc*) &_decode_table[table_idx];
if (DESC_IGN66(desc))
prefixes &= ~PREFIX_OPSZ;
instr->type = desc->type;
instr->flags = prefixes & 0x7f;
if (mode == DECODE_64)
instr->flags |= FD_FLAG_64;
instr->address = address;
uint8_t op_size = 0;
if (DESC_SIZE8(desc))
op_size = 1;
else if (mode == DECODE_64 && (prefixes & PREFIX_REXW))
unsigned op_size = 4;
if (DESC_OPSIZE(desc) == 2 && mode == DECODE_64) // DEF64
op_size = 8;
else if (prefixes & PREFIX_OPSZ)
if ((prefixes & PREFIX_OPSZ) && !DESC_IGN66(desc)) // opsize override
op_size = 2;
else if (mode == DECODE_64 && DESC_SIZED64(desc))
if (mode == DECODE_64 && (prefixes & PREFIX_REXW || DESC_OPSIZE(desc) == 3))
op_size = 8;
else
op_size = 4;
// Note: operand size is updates for jumps when handling immediate operands.
if (DESC_OPSIZE(desc) == 1) // force byte
op_size = 1;
uint8_t vec_size = 16;
if (prefixes & PREFIX_VEXL)
@@ -551,10 +544,6 @@ fd_decode(const uint8_t* buffer, size_t len_sz, int mode_int, uintptr_t address,
// 6/7 = offset, operand-sized/8 bit (used for jumps/calls)
int imm_byte = imm_control & 1;
int imm_offset = imm_control & 2;
// Jumps are always 8 or 32 bit on x86-64, and the operand size is
// forced to 64 bit.
if (mode == DECODE_64 && UNLIKELY(imm_offset))
op_size = 8;
uint8_t imm_size;
if (imm_byte)

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@@ -83,22 +83,22 @@
6d NP - - - - INS INSTR_WIDTH ENC_REP
6e NP - - - - OUTS SIZE_8 INSTR_WIDTH ENC_REP
6f NP - - - - OUTS INSTR_WIDTH ENC_REP
70 D IMM - - - JO DEF64 IMM_8
71 D IMM - - - JNO DEF64 IMM_8
72 D IMM - - - JC DEF64 IMM_8
73 D IMM - - - JNC DEF64 IMM_8
74 D IMM - - - JZ DEF64 IMM_8
75 D IMM - - - JNZ DEF64 IMM_8
76 D IMM - - - JBE DEF64 IMM_8
77 D IMM - - - JA DEF64 IMM_8
78 D IMM - - - JS DEF64 IMM_8
79 D IMM - - - JNS DEF64 IMM_8
7a D IMM - - - JP DEF64 IMM_8
7b D IMM - - - JNP DEF64 IMM_8
7c D IMM - - - JL DEF64 IMM_8
7d D IMM - - - JGE DEF64 IMM_8
7e D IMM - - - JLE DEF64 IMM_8
7f D IMM - - - JG DEF64 IMM_8
70 D IMM - - - JO FORCE64 IMM_8
71 D IMM - - - JNO FORCE64 IMM_8
72 D IMM - - - JC FORCE64 IMM_8
73 D IMM - - - JNC FORCE64 IMM_8
74 D IMM - - - JZ FORCE64 IMM_8
75 D IMM - - - JNZ FORCE64 IMM_8
76 D IMM - - - JBE FORCE64 IMM_8
77 D IMM - - - JA FORCE64 IMM_8
78 D IMM - - - JS FORCE64 IMM_8
79 D IMM - - - JNS FORCE64 IMM_8
7a D IMM - - - JP FORCE64 IMM_8
7b D IMM - - - JNP FORCE64 IMM_8
7c D IMM - - - JL FORCE64 IMM_8
7d D IMM - - - JGE FORCE64 IMM_8
7e D IMM - - - JLE FORCE64 IMM_8
7f D IMM - - - JG FORCE64 IMM_8
80/0 MI GP IMM - - ADD SIZE_8 LOCK
80/1 MI GP IMM - - OR SIZE_8 LOCK
80/2 MI GP IMM - - ADC SIZE_8 LOCK
@@ -187,14 +187,15 @@ c1/4 MI GP IMM8 - - SHL
c1/5 MI GP IMM8 - - SHR
c1/7 MI GP IMM8 - - SAR
# RET immediate size handled in code
c2 I IMM16 - - - RET DEF64 INSTR_WIDTH
c3 NP - - - - RET DEF64 INSTR_WIDTH
c2 I IMM16 - - - RET FORCE64 INSTR_WIDTH
c3 NP - - - - RET FORCE64 INSTR_WIDTH
c4/m RM GP MEMZ - - LES ONLY32
c5/m RM GP MEMZ - - LDS ONLY32
c6/0 MI GP IMM - - MOV SIZE_8
c6f8 I IMM8 - - - XABORT
c7/0 MI GP IMM - - MOV
c7f8 D IMM - - - XBEGIN
c7f8 D IMM32 - - - XBEGIN ONLY32
c7f8 D IMM64 - - - XBEGIN ONLY64
# ENTER immediate handled in code
c8 I IMM32 - - - ENTER DEF64 INSTR_WIDTH
c9 NP - - - - LEAVE DEF64 INSTR_WIDTH
@@ -238,18 +239,18 @@ d5 I IMM - - - AAD ONLY32 SIZE_8
#d6 unused
d7 NP - - - - XLATB
#d8-df FPU Escape
e0 D IMM - - - LOOPNZ DEF64 IMM_8
e1 D IMM - - - LOOPZ DEF64 IMM_8
e2 D IMM - - - LOOP DEF64 IMM_8
e3 D IMM - - - JCXZ DEF64 IMM_8
e0 D IMM - - - LOOPNZ FORCE64 IMM_8
e1 D IMM - - - LOOPZ FORCE64 IMM_8
e2 D IMM - - - LOOP FORCE64 IMM_8
e3 D IMM - - - JCXZ FORCE64 IMM_8
e4 IA GP IMM8 - - IN SIZE_8
e5 IA GP IMM8 - - IN
e6 IA GP IMM8 - - OUT SIZE_8
e7 IA GP IMM8 - - OUT
e8 D IMM - - - CALL DEF64
e9 D IMM - - - JMP DEF64
e8 D IMM - - - CALL FORCE64
e9 D IMM - - - JMP FORCE64
#ea JMPf TODO, ONLY32
eb D IMM - - - JMP DEF64 IMM_8
eb D IMM - - - JMP FORCE64 IMM_8
ec NP - - - - IN SIZE_8 INSTR_WIDTH
ed NP - - - - IN INSTR_WIDTH
ee NP - - - - OUT SIZE_8 INSTR_WIDTH
@@ -284,9 +285,9 @@ fe/0 M GP - - - INC SIZE_8 LOCK
fe/1 M GP - - - DEC SIZE_8 LOCK
ff/0 M GP - - - INC LOCK
ff/1 M GP - - - DEC LOCK
ff/2 M GP - - - CALL DEF64
ff/2 M GP - - - CALL FORCE64
ff/3m M MEMZ - - - CALLF
ff/4 M GP - - - JMP DEF64
ff/4 M GP - - - JMP FORCE64
ff/5m M MEMZ - - - JMPF
ff/6 M GP - - - PUSH DEF64
0f00/0 M GP16 - - - SLDT
@@ -377,22 +378,22 @@ NP.0f37 NP - - - - GETSEC
0f4d RM GP GP - - CMOVGE
0f4e RM GP GP - - CMOVLE
0f4f RM GP GP - - CMOVG
0f80 D IMM - - - JO DEF64
0f81 D IMM - - - JNO DEF64
0f82 D IMM - - - JC DEF64
0f83 D IMM - - - JNC DEF64
0f84 D IMM - - - JZ DEF64
0f85 D IMM - - - JNZ DEF64
0f86 D IMM - - - JBE DEF64
0f87 D IMM - - - JA DEF64
0f88 D IMM - - - JS DEF64
0f89 D IMM - - - JNS DEF64
0f8a D IMM - - - JP DEF64
0f8b D IMM - - - JNP DEF64
0f8c D IMM - - - JL DEF64
0f8d D IMM - - - JGE DEF64
0f8e D IMM - - - JLE DEF64
0f8f D IMM - - - JG DEF64
0f80 D IMM - - - JO FORCE64
0f81 D IMM - - - JNO FORCE64
0f82 D IMM - - - JC FORCE64
0f83 D IMM - - - JNC FORCE64
0f84 D IMM - - - JZ FORCE64
0f85 D IMM - - - JNZ FORCE64
0f86 D IMM - - - JBE FORCE64
0f87 D IMM - - - JA FORCE64
0f88 D IMM - - - JS FORCE64
0f89 D IMM - - - JNS FORCE64
0f8a D IMM - - - JP FORCE64
0f8b D IMM - - - JNP FORCE64
0f8c D IMM - - - JL FORCE64
0f8d D IMM - - - JGE FORCE64
0f8e D IMM - - - JLE FORCE64
0f8f D IMM - - - JG FORCE64
0f90 M GP - - - SETO SIZE_8
0f91 M GP - - - SETNO SIZE_8
0f92 M GP - - - SETC SIZE_8

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@@ -39,8 +39,7 @@ InstrFlags = bitstruct("InstrFlags", [
"op1_size:2",
"op2_size:2",
"op3_size:2",
"size8:1",
"sized64:1",
"opsize:2",
"size_fix1:3",
"size_fix2:2",
"instr_width:1",
@@ -106,6 +105,7 @@ OPKINDS = {
"IMM8": OpKind(1, OpKind.K_IMM),
"IMM16": OpKind(2, OpKind.K_IMM),
"IMM32": OpKind(4, OpKind.K_IMM),
"IMM64": OpKind(8, OpKind.K_IMM),
"GP": OpKind(OpKind.SZ_OP, "GP"),
"GP8": OpKind(1, "GP"),
"GP16": OpKind(2, "GP"),
@@ -179,8 +179,9 @@ class InstrDesc(NamedTuple):
raise Exception("invalid regty for op 3, must be VEC")
# Miscellaneous Flags
if "DEF64" in self.flags: flags.sized64 = 1
if "SIZE_8" in self.flags: flags.size8 = 1
if "SIZE_8" in self.flags: flags.opsize = 1
if "DEF64" in self.flags: flags.opsize = 2
if "FORCE64" in self.flags: flags.opsize = 3
if "INSTR_WIDTH" in self.flags: flags.instr_width = 1
if "LOCK" in self.flags: flags.lock = 1
if "VSIB" in self.flags: flags.vsib = 1
@@ -191,7 +192,7 @@ class InstrDesc(NamedTuple):
if flags.imm_control >= 4:
imm_op = next(op for op in self.operands if op.kind == OpKind.K_IMM)
if ("IMM_8" in self.flags or imm_op.size == 1 or
(imm_op.size == OpKind.SZ_OP and flags.size8)):
(imm_op.size == OpKind.SZ_OP and "SIZE_8" in self.flags)):
flags.imm_control |= 1
enc = flags._encode(6)
@@ -487,6 +488,10 @@ def encode_table(entries):
prepend_opsize = max(opsizes) > 0 and not separate_opsize
prepend_vecsize = hasvex and max(vecsizes) > 0 and not separate_opsize
if "FORCE64" in desc.flags:
opsizes = {64}
prepend_opsize = False
optypes = ["", "", "", ""]
enc = ENCODINGS[desc.encoding]
if enc.modrm_idx:
@@ -536,7 +541,7 @@ def encode_table(entries):
tys_i = sum(ty << (4*i) for i, ty in enumerate(tys))
opc_s = hex(opc_i) + opc_flags + prefix[1]
if opsize == 16: opc_s += "|OPC_66"
if opsize == 64 and "DEF64" not in desc.flags: opc_s += "|OPC_REXW"
if opsize == 64 and "DEF64" not in desc.flags and "FORCE64" not in desc.flags: opc_s += "|OPC_REXW"
# Construct mnemonic name
mnem_name = {"MOVABS": "MOV", "XCHG_NOP": "XCHG"}.get(desc.mnemonic, desc.mnemonic)

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@@ -204,6 +204,11 @@ main(int argc, char** argv)
TEST64("\x66\xeb\xff", "[JMP off8:rip+0xffffffffffffffff]");
TEST("\x66\xe9\x00", "PARTIAL");
TEST("\x66\xe9", "PARTIAL");
TEST32("\xc7\xf8\xd3\x9c\xff\xff", "[XBEGIN off4:eip+0xffff9cd3]");
TEST32("\x66\xc7\xf8\xd3\x9c", "[XBEGIN off4:eip+0xffff9cd3]");
TEST64("\xc7\xf8\xd3\x9c\xff\xff", "[XBEGIN off8:rip+0xffffffffffff9cd3]");
TEST64("\x66\xc7\xf8\xd3\x9c", "[XBEGIN off8:rip+0xffffffffffff9cd3]");
TEST("\xa5", "[MOVS_4]");
TEST("\x66\xa5", "[MOVS_2]");
@@ -216,10 +221,14 @@ main(int argc, char** argv)
TEST64("\x48\x0f\xbf\xc2", "[MOVSX reg8:r0 reg2:r2]");
TEST64("\x48\x63\xc2", "[MOVSX reg8:r0 reg4:r2]");
TEST("\x66\xc3", "[RET_2]");
TEST("\x66\xc2\x00\x00", "[RET_2 imm2:0x0]");
TEST("\x66\xc2\x0d\x00", "[RET_2 imm2:0xd]");
TEST("\x66\xc2\x0d\xff", "[RET_2 imm2:0xff0d]");
TEST32("\x66\xc3", "[RET_2]");
TEST32("\x66\xc2\x00\x00", "[RET_2 imm2:0x0]");
TEST32("\x66\xc2\x0d\x00", "[RET_2 imm2:0xd]");
TEST32("\x66\xc2\x0d\xff", "[RET_2 imm2:0xff0d]");
TEST64("\x66\xc3", "[RET_8]");
TEST64("\x66\xc2\x00\x00", "[RET_8 imm2:0x0]");
TEST64("\x66\xc2\x0d\x00", "[RET_8 imm2:0xd]");
TEST64("\x66\xc2\x0d\xff", "[RET_8 imm2:0xff0d]");
TEST32("\xc3", "[RET_4]");
TEST32("\xc2\x00\x00", "[RET_4 imm2:0x0]");
TEST32("\xc2\x0d\x00", "[RET_4 imm2:0xd]");

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@@ -81,7 +81,6 @@ main(int argc, char** argv)
// TEST("\x66\x90", FE_XCHG16rr, FE_AX, FE_AX);
TEST("\xc2\x00\x00", FE_RETi, 0);
TEST("\xff\xd0", FE_CALLr, FE_AX);
TEST("\x66\xff\xd0", FE_CALL16r, FE_AX);
TEST("\x05\x00\x01\x00\x00", FE_ADD32ri, FE_AX, 0x100);
TEST("\x66\x05\x00\x01", FE_ADD16ri, FE_AX, 0x100);
TEST("\xb8\x05\x00\x01\x00", FE_MOV32ri, FE_AX, 0x10005);