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Major rewrite of hijack code
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I would like to give a big thanks to Eugene Shatokhin for his help with this
code. He sent me a copy of his detour module, which is not yet published, and
it contained the code (which now mostly resides in hijacks.c) to copy and fixup
functions.

This module now appers very stable, and functions are now wrapped properly
rather than hijacked completely. I'll have to play around with this more, but
it's great so far.

Thanks again, Eugene!
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Corey Henderson committed Jun 29, 2011
1 parent 1aca113 commit 5f9347b
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Showing 16 changed files with 3,663 additions and 167 deletions.
68 changes: 55 additions & 13 deletions Makefile
@@ -1,28 +1,70 @@
ifneq ($(KERNELRELEASE),)
obj-m := tpe.o
tpe-objs := addrs.o core.o hijacks.o init.o security.o symbols.o
else
MODULE_NAME := tpe

# This subdirectory contains necessary files for both x86 and x86-64.
ARCH_DIR := arch/x86

# This auxiliary file will be generated during the build (x86 instruction
# tables as C code).
INAT_TABLES_FILE := inat-tables.h

ifeq ($(KERNELRELEASE),)
# 'Out-of-kernel' part

KDIR=$(shell sh ./scripts/find_kernel_src.sh)
MODULE_SOURCES := \
core.c \
init.c \
security.c \
symbols.c \
malloc.c \
hijacks.c

all:
KBUILD_DIR=$(shell sh ./scripts/find_kernel_src.sh)
PWD := $(shell pwd)

all: $(MODULE_NAME).ko

$(MODULE_NAME).ko: $(MODULE_SOURCES)

perl ./scripts/gen_addrs.pl > addrs.c

make -C $(KDIR) M=$(PWD) modules
$(MAKE) -C $(KBUILD_DIR) M=$(PWD) modules

test: all
test: $(MODULE_NAME).ko

sudo sh ./scripts/test-tpe.sh

install: $(MODULE_NAME).ko

install: all

sudo /sbin/rmmod tpe || :
sudo /sbin/insmod tpe.ko
sudo /sbin/rmmod $(MODULE_NAME) || :
sudo /sbin/insmod $(MODULE_NAME).ko

clean:
$(MAKE) -C $(KBUILD_DIR) M=$(PWD) clean

make -C $(KDIR) M=$(PWD) clean
rm -f addrs.c Module*

.PHONY: all clean install test

else
# KBuild part.
# It is used by the kernel build system to actually build the module.
ccflags-y := -I$(src) -I$(src)/$(ARCH_DIR)/include -I$(obj)/$(ARCH_DIR)/lib

obj-m := $(MODULE_NAME).o
$(MODULE_NAME)-y := \
addrs.o \
core.o \
init.o \
security.o \
symbols.o \
malloc.o \
hijacks.o \
$(ARCH_DIR)/lib/inat.o \
$(ARCH_DIR)/lib/insn.o

$(obj)/$(ARCH_DIR)/lib/inat.o: $(obj)/$(ARCH_DIR)/lib/$(INAT_TABLES_FILE) $(src)/$(ARCH_DIR)/lib/inat.c

$(obj)/$(ARCH_DIR)/lib/$(INAT_TABLES_FILE): $(src)/$(ARCH_DIR)/lib/x86-opcode-map.txt
LC_ALL=C awk -f $(src)/$(ARCH_DIR)/tools/gen-insn-attr-x86.awk $< > $@

endif
220 changes: 220 additions & 0 deletions arch/x86/include/asm/inat.h
@@ -0,0 +1,220 @@
#ifndef _ASM_X86_INAT_H
#define _ASM_X86_INAT_H
/*
* x86 instruction attributes
*
* Written by Masami Hiramatsu <mhiramat@redhat.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*
*/
#include <asm/inat_types.h>

/*
* Internal bits. Don't use bitmasks directly, because these bits are
* unstable. You should use checking functions.
*/

#define INAT_OPCODE_TABLE_SIZE 256
#define INAT_GROUP_TABLE_SIZE 8

/* Legacy last prefixes */
#define INAT_PFX_OPNDSZ 1 /* 0x66 */ /* LPFX1 */
#define INAT_PFX_REPE 2 /* 0xF3 */ /* LPFX2 */
#define INAT_PFX_REPNE 3 /* 0xF2 */ /* LPFX3 */
/* Other Legacy prefixes */
#define INAT_PFX_LOCK 4 /* 0xF0 */
#define INAT_PFX_CS 5 /* 0x2E */
#define INAT_PFX_DS 6 /* 0x3E */
#define INAT_PFX_ES 7 /* 0x26 */
#define INAT_PFX_FS 8 /* 0x64 */
#define INAT_PFX_GS 9 /* 0x65 */
#define INAT_PFX_SS 10 /* 0x36 */
#define INAT_PFX_ADDRSZ 11 /* 0x67 */
/* x86-64 REX prefix */
#define INAT_PFX_REX 12 /* 0x4X */
/* AVX VEX prefixes */
#define INAT_PFX_VEX2 13 /* 2-bytes VEX prefix */
#define INAT_PFX_VEX3 14 /* 3-bytes VEX prefix */

#define INAT_LSTPFX_MAX 3
#define INAT_LGCPFX_MAX 11

/* Immediate size */
#define INAT_IMM_BYTE 1
#define INAT_IMM_WORD 2
#define INAT_IMM_DWORD 3
#define INAT_IMM_QWORD 4
#define INAT_IMM_PTR 5
#define INAT_IMM_VWORD32 6
#define INAT_IMM_VWORD 7

/* Legacy prefix */
#define INAT_PFX_OFFS 0
#define INAT_PFX_BITS 4
#define INAT_PFX_MAX ((1 << INAT_PFX_BITS) - 1)
#define INAT_PFX_MASK (INAT_PFX_MAX << INAT_PFX_OFFS)
/* Escape opcodes */
#define INAT_ESC_OFFS (INAT_PFX_OFFS + INAT_PFX_BITS)
#define INAT_ESC_BITS 2
#define INAT_ESC_MAX ((1 << INAT_ESC_BITS) - 1)
#define INAT_ESC_MASK (INAT_ESC_MAX << INAT_ESC_OFFS)
/* Group opcodes (1-16) */
#define INAT_GRP_OFFS (INAT_ESC_OFFS + INAT_ESC_BITS)
#define INAT_GRP_BITS 5
#define INAT_GRP_MAX ((1 << INAT_GRP_BITS) - 1)
#define INAT_GRP_MASK (INAT_GRP_MAX << INAT_GRP_OFFS)
/* Immediates */
#define INAT_IMM_OFFS (INAT_GRP_OFFS + INAT_GRP_BITS)
#define INAT_IMM_BITS 3
#define INAT_IMM_MASK (((1 << INAT_IMM_BITS) - 1) << INAT_IMM_OFFS)
/* Flags */
#define INAT_FLAG_OFFS (INAT_IMM_OFFS + INAT_IMM_BITS)
#define INAT_MODRM (1 << (INAT_FLAG_OFFS))
#define INAT_FORCE64 (1 << (INAT_FLAG_OFFS + 1))
#define INAT_SCNDIMM (1 << (INAT_FLAG_OFFS + 2))
#define INAT_MOFFSET (1 << (INAT_FLAG_OFFS + 3))
#define INAT_VARIANT (1 << (INAT_FLAG_OFFS + 4))
#define INAT_VEXOK (1 << (INAT_FLAG_OFFS + 5))
#define INAT_VEXONLY (1 << (INAT_FLAG_OFFS + 6))
/* Attribute making macros for attribute tables */
#define INAT_MAKE_PREFIX(pfx) (pfx << INAT_PFX_OFFS)
#define INAT_MAKE_ESCAPE(esc) (esc << INAT_ESC_OFFS)
#define INAT_MAKE_GROUP(grp) ((grp << INAT_GRP_OFFS) | INAT_MODRM)
#define INAT_MAKE_IMM(imm) (imm << INAT_IMM_OFFS)

/* Attribute search APIs */
extern insn_attr_t inat_get_opcode_attribute(insn_byte_t opcode);
extern insn_attr_t inat_get_escape_attribute(insn_byte_t opcode,
insn_byte_t last_pfx,
insn_attr_t esc_attr);
extern insn_attr_t inat_get_group_attribute(insn_byte_t modrm,
insn_byte_t last_pfx,
insn_attr_t esc_attr);
extern insn_attr_t inat_get_avx_attribute(insn_byte_t opcode,
insn_byte_t vex_m,
insn_byte_t vex_pp);

/* Attribute checking functions */
static inline int inat_is_legacy_prefix(insn_attr_t attr)
{
attr &= INAT_PFX_MASK;
return attr && attr <= INAT_LGCPFX_MAX;
}

static inline int inat_is_address_size_prefix(insn_attr_t attr)
{
return (attr & INAT_PFX_MASK) == INAT_PFX_ADDRSZ;
}

static inline int inat_is_operand_size_prefix(insn_attr_t attr)
{
return (attr & INAT_PFX_MASK) == INAT_PFX_OPNDSZ;
}

static inline int inat_is_rex_prefix(insn_attr_t attr)
{
return (attr & INAT_PFX_MASK) == INAT_PFX_REX;
}

static inline int inat_last_prefix_id(insn_attr_t attr)
{
if ((attr & INAT_PFX_MASK) > INAT_LSTPFX_MAX)
return 0;
else
return attr & INAT_PFX_MASK;
}

static inline int inat_is_vex_prefix(insn_attr_t attr)
{
attr &= INAT_PFX_MASK;
return attr == INAT_PFX_VEX2 || attr == INAT_PFX_VEX3;
}

static inline int inat_is_vex3_prefix(insn_attr_t attr)
{
return (attr & INAT_PFX_MASK) == INAT_PFX_VEX3;
}

static inline int inat_is_escape(insn_attr_t attr)
{
return attr & INAT_ESC_MASK;
}

static inline int inat_escape_id(insn_attr_t attr)
{
return (attr & INAT_ESC_MASK) >> INAT_ESC_OFFS;
}

static inline int inat_is_group(insn_attr_t attr)
{
return attr & INAT_GRP_MASK;
}

static inline int inat_group_id(insn_attr_t attr)
{
return (attr & INAT_GRP_MASK) >> INAT_GRP_OFFS;
}

static inline int inat_group_common_attribute(insn_attr_t attr)
{
return attr & ~INAT_GRP_MASK;
}

static inline int inat_has_immediate(insn_attr_t attr)
{
return attr & INAT_IMM_MASK;
}

static inline int inat_immediate_size(insn_attr_t attr)
{
return (attr & INAT_IMM_MASK) >> INAT_IMM_OFFS;
}

static inline int inat_has_modrm(insn_attr_t attr)
{
return attr & INAT_MODRM;
}

static inline int inat_is_force64(insn_attr_t attr)
{
return attr & INAT_FORCE64;
}

static inline int inat_has_second_immediate(insn_attr_t attr)
{
return attr & INAT_SCNDIMM;
}

static inline int inat_has_moffset(insn_attr_t attr)
{
return attr & INAT_MOFFSET;
}

static inline int inat_has_variant(insn_attr_t attr)
{
return attr & INAT_VARIANT;
}

static inline int inat_accept_vex(insn_attr_t attr)
{
return attr & INAT_VEXOK;
}

static inline int inat_must_vex(insn_attr_t attr)
{
return attr & INAT_VEXONLY;
}
#endif
29 changes: 29 additions & 0 deletions arch/x86/include/asm/inat_types.h
@@ -0,0 +1,29 @@
#ifndef _ASM_X86_INAT_TYPES_H
#define _ASM_X86_INAT_TYPES_H
/*
* x86 instruction attributes
*
* Written by Masami Hiramatsu <mhiramat@redhat.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*
*/

/* Instruction attributes */
typedef unsigned int insn_attr_t;
typedef unsigned char insn_byte_t;
typedef signed int insn_value_t;

#endif

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