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Diffstat (limited to 'sandbox/linux/seccomp/x86_decode.cc')
-rw-r--r--sandbox/linux/seccomp/x86_decode.cc310
1 files changed, 0 insertions, 310 deletions
diff --git a/sandbox/linux/seccomp/x86_decode.cc b/sandbox/linux/seccomp/x86_decode.cc
deleted file mode 100644
index 1b55139..0000000
--- a/sandbox/linux/seccomp/x86_decode.cc
+++ /dev/null
@@ -1,310 +0,0 @@
-// Copyright (c) 2010 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#include "x86_decode.h"
-
-namespace playground {
-
-#if defined(__x86_64__) || defined(__i386__)
-unsigned short next_inst(const char **ip, bool is64bit, bool *has_prefix,
- char **rex_ptr, char **mod_rm_ptr, char **sib_ptr,
- bool *is_group) {
- enum {
- BYTE_OP = (1<<1), // 0x02
- IMM = (1<<2), // 0x04
- IMM_BYTE = (2<<2), // 0x08
- MEM_ABS = (3<<2), // 0x0C
- MODE_MASK = (7<<2), // 0x1C
- MOD_RM = (1<<5), // 0x20
- STACK = (1<<6), // 0x40
- GROUP = (1<<7), // 0x80
- GROUP_MASK = 0x7F,
- };
-
- static unsigned char opcode_types[512] = {
- 0x23, 0x21, 0x23, 0x21, 0x09, 0x05, 0x01, 0x01, // 0x00 - 0x07
- 0x23, 0x21, 0x23, 0x21, 0x09, 0x05, 0x01, 0x00, // 0x08 - 0x0F
- 0x23, 0x21, 0x23, 0x21, 0x09, 0x05, 0x01, 0x01, // 0x10 - 0x17
- 0x23, 0x21, 0x23, 0x21, 0x09, 0x05, 0x01, 0x01, // 0x18 - 0x1F
- 0x23, 0x21, 0x23, 0x21, 0x09, 0x05, 0x00, 0x01, // 0x20 - 0x27
- 0x23, 0x21, 0x23, 0x21, 0x09, 0x05, 0x00, 0x01, // 0x28 - 0x2F
- 0x23, 0x21, 0x23, 0x21, 0x09, 0x05, 0x00, 0x01, // 0x30 - 0x37
- 0x23, 0x21, 0x23, 0x21, 0x09, 0x05, 0x00, 0x01, // 0x38 - 0x3F
- 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, // 0x40 - 0x47
- 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, // 0x48 - 0x4F
- 0x41, 0x41, 0x41, 0x41, 0x41, 0x41, 0x41, 0x41, // 0x50 - 0x57
- 0x41, 0x41, 0x41, 0x41, 0x41, 0x41, 0x41, 0x41, // 0x58 - 0x5F
- 0x01, 0x01, 0x21, 0x21, 0x00, 0x00, 0x00, 0x00, // 0x60 - 0x67
- 0x45, 0x25, 0x49, 0x29, 0x03, 0x01, 0x03, 0x01, // 0x68 - 0x6F
- 0x09, 0x09, 0x09, 0x09, 0x09, 0x09, 0x09, 0x09, // 0x70 - 0x77
- 0x09, 0x09, 0x09, 0x09, 0x09, 0x09, 0x09, 0x09, // 0x78 - 0x7F
- 0x27, 0x25, 0x27, 0x29, 0x23, 0x21, 0x23, 0x21, // 0x80 - 0x87
- 0x23, 0x21, 0x23, 0x21, 0x21, 0x21, 0x21, 0x80, // 0x88 - 0x8F
- 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, // 0x90 - 0x97
- 0x01, 0x01, 0x05, 0x01, 0x41, 0x41, 0x01, 0x01, // 0x98 - 0x9F
- 0x0F, 0x0D, 0x0F, 0x0D, 0x03, 0x01, 0x03, 0x01, // 0xA0 - 0xA7
- 0x09, 0x05, 0x03, 0x01, 0x03, 0x01, 0x03, 0x01, // 0xA8 - 0xAF
- 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, // 0xB0 - 0xB7
- 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, 0x05, // 0xB8 - 0xBF
- 0x27, 0x29, 0x01, 0x01, 0x21, 0x21, 0x27, 0x25, // 0xC0 - 0xC7
- 0x01, 0x01, 0x01, 0x01, 0x01, 0x09, 0x01, 0x01, // 0xC8 - 0xCF
- 0x23, 0x21, 0x23, 0x21, 0x09, 0x09, 0x01, 0x01, // 0xD0 - 0xD7
- 0x21, 0x21, 0x21, 0x21, 0x21, 0x21, 0x21, 0x21, // 0xD8 - 0xDF
- 0x09, 0x09, 0x09, 0x09, 0x09, 0x09, 0x09, 0x09, // 0xE0 - 0xE7
- 0x05, 0x05, 0x05, 0x09, 0x03, 0x01, 0x03, 0x01, // 0xE8 - 0xEF
- 0x00, 0x01, 0x00, 0x00, 0x01, 0x01, 0x88, 0x90, // 0xF0 - 0xF7
- 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x98, 0xA0, // 0xF8 - 0xFF
- 0x00, 0xA8, 0x00, 0x00, 0x00, 0x01, 0x01, 0x01, // 0xF00 - 0xF07
- 0x01, 0x01, 0x00, 0x01, 0x00, 0x21, 0x01, 0x00, // 0xF08 - 0xF0F
- 0x21, 0x21, 0x21, 0x21, 0x21, 0x21, 0x21, 0x21, // 0xF10 - 0xF17
- 0x21, 0x21, 0x21, 0x21, 0x21, 0x21, 0x21, 0x21, // 0xF18 - 0xF1F
- 0x21, 0x21, 0x21, 0x21, 0x00, 0x00, 0x00, 0x00, // 0xF20 - 0xF27
- 0x21, 0x21, 0x21, 0x21, 0x21, 0x21, 0x21, 0x21, // 0xF28 - 0xF2F
- 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x00, 0x00, // 0xF30 - 0xF37
- 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, // 0xF38 - 0xF3F
- 0x21, 0x21, 0x21, 0x21, 0x21, 0x21, 0x21, 0x21, // 0xF40 - 0xF47
- 0x21, 0x21, 0x21, 0x21, 0x21, 0x21, 0x21, 0x21, // 0xF48 - 0xF4F
- 0x21, 0x21, 0x21, 0x21, 0x21, 0x21, 0x21, 0x21, // 0xF50 - 0xF57
- 0x21, 0x21, 0x21, 0x21, 0x21, 0x21, 0x21, 0x21, // 0xF58 - 0xF5F
- 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, // 0xF60 - 0xF67
- 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, // 0xF68 - 0xF6F
- 0x21, 0x00, 0x00, 0x00, 0x21, 0x21, 0x21, 0x00, // 0xF70 - 0xF77
- 0x21, 0x21, 0x00, 0x00, 0x21, 0x21, 0x21, 0x21, // 0xF78 - 0xF7F
- 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, // 0xF80 - 0xF87
- 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, // 0xF88 - 0xF8F
- 0x21, 0x21, 0x21, 0x21, 0x21, 0x21, 0x21, 0x21, // 0xF90 - 0xF97
- 0x21, 0x21, 0x21, 0x21, 0x21, 0x21, 0x21, 0x21, // 0xF98 - 0xF9F
- 0x01, 0x01, 0x01, 0x21, 0x29, 0x21, 0x00, 0x00, // 0xFA0 - 0xFA7
- 0x01, 0x01, 0x01, 0x21, 0x29, 0x21, 0x21, 0x21, // 0xFA8 - 0xFAF
- 0x23, 0x21, 0x00, 0x21, 0x00, 0x00, 0x23, 0x21, // 0xFB0 - 0xFB7
- 0x21, 0x00, 0x29, 0x21, 0x21, 0x21, 0x21, 0x21, // 0xFB8 - 0xFBF
- 0x21, 0x21, 0x00, 0x21, 0x00, 0x00, 0x00, 0x21, // 0xFC0 - 0xFC7
- 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, // 0xFC8 - 0xFCF
- 0x21, 0x21, 0x21, 0x21, 0x21, 0x21, 0x21, 0x21, // 0xFD0 - 0xFD7
- 0x21, 0x21, 0x21, 0x21, 0x21, 0x21, 0x21, 0x21, // 0xFD8 - 0xFDF
- 0x21, 0x21, 0x21, 0x21, 0x21, 0x21, 0x21, 0x21, // 0xFE0 - 0xFE7
- 0x21, 0x21, 0x21, 0x21, 0x21, 0x21, 0x21, 0x21, // 0xFE8 - 0xFEF
- 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, // 0xFF0 - 0xFF7
- 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, // 0xFF8 - 0xFFF
- };
-
- static unsigned char group_table[56] = {
- 0x61, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, // Group 1A
- 0x27, 0x27, 0x23, 0x23, 0x23, 0x23, 0x23, 0x23, // Group 3 (Byte)
- 0x25, 0x25, 0x21, 0x21, 0x21, 0x21, 0x21, 0x21, // Group 3
- 0x23, 0x23, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, // Group 4
- 0x21, 0x21, 0x61, 0x21, 0x61, 0x21, 0x61, 0x00, // Group 5
- 0x00, 0x00, 0x21, 0x21, 0x21, 0x00, 0x21, 0x23, // Group 7
- 0x21, 0x00, 0x00, 0x21, 0x21, 0x00, 0x21, 0x00, // Group 7 (Alternate)
- };
-
- const unsigned char *insn_ptr = reinterpret_cast<const unsigned char *>(*ip);
- int operand_width = 4;
- int address_width = 4;
- if (is64bit) {
- address_width = 8;
- }
- unsigned char byte, rex = 0;
- bool found_prefix = false;
- if (rex_ptr) {
- *rex_ptr = 0;
- }
- if (mod_rm_ptr) {
- *mod_rm_ptr = 0;
- }
- if (sib_ptr) {
- *sib_ptr = 0;
- }
- for (;; ++insn_ptr) {
- switch (byte = *insn_ptr) {
- case 0x66: // Operand width prefix
- operand_width ^= 6;
- break;
- case 0x67: // Address width prefix
- address_width ^= is64bit ? 12 : 6;
- break;
- case 0x26: // Segment selector prefixes
- case 0x2e:
- case 0x36:
- case 0x3e:
- case 0x64:
- case 0x65:
- case 0xF0:
- case 0xF2:
- case 0xF3:
- break;
- case 0x40: case 0x41: case 0x42: case 0x43: // 64 bit REX prefixes
- case 0x44: case 0x45: case 0x46: case 0x47:
- case 0x48: case 0x49: case 0x4A: case 0x4B:
- case 0x4C: case 0x4D: case 0x4E: case 0x4F:
- if (is64bit) {
- if (rex_ptr) {
- *rex_ptr = (char *)insn_ptr;
- }
- rex = byte;
- found_prefix = true;
- continue;
- }
- // fall through
- default:
- ++insn_ptr;
- goto no_more_prefixes;
- }
- rex = 0;
- found_prefix = true;
- }
-no_more_prefixes:
- if (has_prefix) {
- *has_prefix = found_prefix;
- }
- if (rex & REX_W) {
- operand_width = 8;
- }
- unsigned char type;
- unsigned short insn = byte;
- unsigned int idx = 0;
- if (byte == 0x0F) {
- byte = *insn_ptr++;
- insn = (insn << 8) | byte;
- idx = 256;
- }
- type = opcode_types[idx + byte];
- bool found_mod_rm = false;
- bool found_group = false;
- bool found_sib = false;
- unsigned char mod_rm = 0;
- unsigned char sib = 0;
- if (type & GROUP) {
- found_mod_rm = true;
- found_group = true;
- mod_rm = *insn_ptr;
- if (mod_rm_ptr) {
- *mod_rm_ptr = (char *)insn_ptr;
- }
- unsigned char group = (type & GROUP_MASK) + ((mod_rm >> 3) & 0x7);
- if ((type & GROUP_MASK) == 40 && (mod_rm >> 6) == 3) {
- group += 8;
- }
- type = group_table[group];
- }
- if (!type) {
- // We know that we still don't decode some of the more obscure
- // instructions, but for all practical purposes that doesn't matter.
- // Compilers are unlikely to output them, and even if we encounter
- // hand-coded assembly, we will soon synchronize to the instruction
- // stream again.
- //
- // std::cerr << "Unsupported instruction at 0x" << std::hex <<
- // std::uppercase << reinterpret_cast<long>(*ip) << " [ ";
- // for (const unsigned char *ptr =
- // reinterpret_cast<const unsigned char *>(*ip);
- // ptr < insn_ptr; ) {
- // std::cerr << std::hex << std::uppercase << std::setw(2) <<
- // std::setfill('0') << (unsigned int)*ptr++ << ' ';
- // }
- // std::cerr << "]" << std::endl;
- } else {
- if (is64bit && (type & STACK)) {
- operand_width = 8;
- }
- if (type & MOD_RM) {
- found_mod_rm = true;
- if (mod_rm_ptr) {
- *mod_rm_ptr = (char *)insn_ptr;
- }
- mod_rm = *insn_ptr++;
- int mod = (mod_rm >> 6) & 0x3;
- int rm = 8*(rex & REX_B) + (mod_rm & 0x7);
- if (mod != 3) {
- if (address_width == 2) {
- switch (mod) {
- case 0:
- if (rm != 6 /* SI */) {
- break;
- }
- // fall through
- case 2:
- insn_ptr++;
- // fall through
- case 1:
- insn_ptr++;
- break;
- }
- } else {
- if ((rm & 0x7) == 4) {
- found_sib = true;
- if (sib_ptr) {
- *sib_ptr = (char *)insn_ptr;
- }
- sib = *insn_ptr++;
- if (!mod && (sib & 0x7) == 5 /* BP */) {
- insn_ptr += 4;
- }
- }
- switch (mod) {
- case 0:
- if (rm != 5 /* BP */) {
- break;
- }
- // fall through
- case 2:
- insn_ptr += 3;
- // fall through
- case 1:
- insn_ptr++;
- break;
- }
- }
- }
- }
- switch (insn) {
- case 0xC8: // ENTER
- insn_ptr++;
- // fall through
- case 0x9A: // CALL (far)
- case 0xC2: // RET (near)
- case 0xCA: // LRET
- case 0xEA: // JMP (far)
- insn_ptr += 2;
- break;
- case 0xF80: case 0xF81: case 0xF82: case 0xF83: // Jcc (rel)
- case 0xF84: case 0xF85: case 0xF86: case 0xF87:
- case 0xF88: case 0xF89: case 0xF8A: case 0xF8B:
- case 0xF8C: case 0xF8D: case 0xF8E: case 0xF8F:
- insn_ptr += operand_width;
- break;
- }
- switch (type & MODE_MASK) {
- case IMM:
- if (!(type & BYTE_OP)) {
- switch (insn) {
- case 0xB8: case 0xB9: case 0xBA: case 0xBB:
- case 0xBC: case 0xBD: case 0xBE: case 0xBF:
- // Allow MOV to/from 64bit addresses
- insn_ptr += operand_width;
- break;
- default:
- insn_ptr += (operand_width == 8) ? 4 : operand_width;
- break;
- }
- break;
- }
- // fall through
- case IMM_BYTE:
- insn_ptr++;
- break;
- case MEM_ABS:
- insn_ptr += address_width;
- break;
- }
- }
- if (is_group) {
- *is_group = found_group;
- }
- *ip = reinterpret_cast<const char *>(insn_ptr);
- return insn;
-}
-#endif
-
-} // namespace
generated by cgit v1.1 at 2025-03-01 13:46:34 +0000