├── .gitignore ├── COPYING ├── INSTALL ├── Makefile.am ├── README.md ├── autogen.sh ├── configure.ac └── module ├── Makefile ├── hook.S ├── ld.c ├── ld.h ├── lend.h ├── schedule-hook.c └── schedule-hook.h /.gitignore: -------------------------------------------------------------------------------- 1 | Makefile 2 | Makefile.in 3 | -------------------------------------------------------------------------------- /COPYING: -------------------------------------------------------------------------------- 1 | GNU GENERAL PUBLIC LICENSE 2 | Version 3, 29 June 2007 3 | 4 | Copyright (C) 2007 Free Software Foundation, Inc. 5 | Everyone is permitted to copy and distribute verbatim copies 6 | of this license document, but changing it is not allowed. 7 | 8 | Preamble 9 | 10 | The GNU General Public License is a free, copyleft license for 11 | software and other kinds of works. 12 | 13 | The licenses for most software and other practical works are designed 14 | to take away your freedom to share and change the works. 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It is safest 630 | to attach them to the start of each source file to most effectively 631 | state the exclusion of warranty; and each file should have at least 632 | the "copyright" line and a pointer to where the full notice is found. 633 | 634 | 635 | Copyright (C) 636 | 637 | This program is free software: you can redistribute it and/or modify 638 | it under the terms of the GNU General Public License as published by 639 | the Free Software Foundation, either version 3 of the License, or 640 | (at your option) any later version. 641 | 642 | This program is distributed in the hope that it will be useful, 643 | but WITHOUT ANY WARRANTY; without even the implied warranty of 644 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 645 | GNU General Public License for more details. 646 | 647 | You should have received a copy of the GNU General Public License 648 | along with this program. If not, see . 649 | 650 | Also add information on how to contact you by electronic and paper mail. 651 | 652 | If the program does terminal interaction, make it output a short 653 | notice like this when it starts in an interactive mode: 654 | 655 | Copyright (C) 656 | This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'. 657 | This is free software, and you are welcome to redistribute it 658 | under certain conditions; type `show c' for details. 659 | 660 | The hypothetical commands `show w' and `show c' should show the appropriate 661 | parts of the General Public License. Of course, your program's commands 662 | might be different; for a GUI interface, you would use an "about box". 663 | 664 | You should also get your employer (if you work as a programmer) or school, 665 | if any, to sign a "copyright disclaimer" for the program, if necessary. 666 | For more information on this, and how to apply and follow the GNU GPL, see 667 | . 668 | 669 | The GNU General Public License does not permit incorporating your program 670 | into proprietary programs. If your program is a subroutine library, you 671 | may consider it more useful to permit linking proprietary applications with 672 | the library. If this is what you want to do, use the GNU Lesser General 673 | Public License instead of this License. But first, please read 674 | . 675 | -------------------------------------------------------------------------------- /INSTALL: -------------------------------------------------------------------------------- 1 | schedule-hook Installation Instructions 2 | *************************************** 3 | 4 | 5 | Prerequisites 6 | ============= 7 | 8 | This software contains a Linux kernel module and a shared library. 9 | Therefore this should be a reasonable list of prerequisites: 10 | 11 | - Linux Kernel, version >= 2.6.26 12 | - Linux Kernel headers 13 | - gcc C compiler 14 | - System map and configuration for the current kernel version installed 15 | in /boot/ 16 | - udev to set correct permissions on the created device file, looking 17 | for new rules in /etc/udev/rules.d/ 18 | 19 | 20 | Basic Installation 21 | ================== 22 | 23 | To generate configuration and installation scripts, run `./autogen.sh' 24 | To install the schedule-hook kernel module the 25 | shell commands `./configure; make; make install' should do all the jobs. 26 | When running make install, this should be done with administrator privileges 27 | to install the kernel module in the extra/ modules' tree. 28 | `modprobe -a` is run as well at the end of make install, so the module 29 | is made visible to the system. 30 | 31 | Please note that during the execution of ./configure, the kernel map is 32 | inspected looking for symbols. Therefore, if the kernel is changed, ./configure 33 | should be run again. Running only `make` could generate a module which is 34 | incorrect. 35 | 36 | -------------------------------------------------------------------------------- /Makefile.am: -------------------------------------------------------------------------------- 1 | ACLOCAL_AMFLAGS = -I m4 2 | AM_CPPFLAGS = -I$(abs_top_srcdir) 3 | EXTRA_DIST = COPYING INSTALL README \ 4 | module/Makefile module/schedule-hook.c module/schedule-hook.h module/83-schedule-hook.rules 5 | 6 | udevdir = /etc/udev/rules.d 7 | initdir = @sysconfdir@/init.d 8 | 9 | #udev_DATA = module/83-schedule-hook.rules 10 | 11 | #lib_LIBRARIES = libovertick.a 12 | #libovertick_a_SOURCES=lib/overticklib.c 13 | 14 | #include_HEADERS = lib/overtick.h 15 | 16 | module/schedule.ko: module/schedule-hook.c module/hook.S 17 | test -f $(builddir)/module/Makefile || $(LN_S) $(abs_top_srcdir)/module/Makefile $(builddir)/module/ 18 | test -f $(builddir)/module/schedule-hook.c || $(LN_S) $(abs_top_srcdir)/module/schedule-hook.c $(builddir)/module/ 19 | test -f $(builddir)/module/schedule-hook.h || $(LN_S) $(abs_top_srcdir)/module/schedule-hook.h $(builddir)/module/ 20 | $(MAKE) -C $(KERNEL_SRC) M=$(abs_top_builddir)/module EXTRA_CFLAGS="-Wall \ 21 | -DFTS_ADDR=$(FTS_ADDR) -DFTS_ADDR_NEXT=$(FTS_ADDR_NEXT)" 22 | 23 | all-local: module/schedule.ko 24 | 25 | install-exec-hook: module/schedule.ko 26 | test -z "$(DESTDIR)$(KERNEL_MOD)" || $(MKDIR_P) "$(DESTDIR)$(KERNEL_MOD)" 27 | $(INSTALL) $(builddir)/module/schedule.ko $(DESTDIR)$(KERNEL_MOD)/schedule.ko 28 | depmod -a 29 | 30 | uninstall-hook: 31 | $(RM) $(DESTDIR)$(KERNEL_MOD)/schedule.ko 32 | depmod -a 33 | 34 | clean-local: 35 | -$(MAKE) -C $(KERNEL_SRC) M=$(abs_top_builddir)/module clean 36 | 37 | -------------------------------------------------------------------------------- /README.md: -------------------------------------------------------------------------------- 1 | # schedule-hook 2 | A kernel module that dynamically patches the Linux kernel scheduler so as to allow running a custom function upon thread reschedule 3 | This is the schedule-hook kernel module, to allow running a custom function 4 | e.g. in another module, upon thread reschedule 5 | 6 | This module can be used either in cross compilation with the one containing 7 | the custom function or not 8 | 9 | This module patches at run-time the kernel schedule() and enables running a schedule-hook 10 | function as the last task of thread re-schedule 11 | 12 | The schdule-hook function is embedded within this module, it checks the value of a function pointer 13 | and in case it is not null the target functio is called 14 | 15 | In cross compilation the function pointer is exported as a symbol to be updated while mounting 16 | the module containing the custom functions to be run 17 | 18 | Otherwise, the function ponter is accessible as a pseudofile called 19 | /sys/module/schedule_hook/parameters/the_hook 20 | 21 | In the latter configuraiton, after mounting the module, you can load any function pointer 22 | you would like (pointing to kernel stuff) by writing it on that pseudofile 23 | 24 | The custom function to be run needs to get no paramter in input 25 | 26 | Please check with the follosing configuration macros to manage the configuration of this module: 27 | - DEBUG and DEBUG_SCHEDULE_HOOK for enalbing or disabling debugging/audit stuff 28 | - SYS_FS for enabling of disabling the reliance on /sys 29 | 30 | NOTE: the custom function is expected to be non-blocking, 31 | in case it is blocking the unmount of this module may hang 32 | 33 | NOTE: this module shoudl be unmounted before unmounting the one containing the custom function 34 | otherwise your kernel wil likely crash 35 | 36 | The code has been developed by: 37 | - Francesco Quaglia 38 | - Alessandro Pellegrini 39 | 40 | and is Copyright (C) 2015 HPDCS Group, http://www.dis.uniroma1.it/~hpdcs 41 | 42 | For installation and usage information, please refer to INSTALL. 43 | 44 | -------------------------------------------------------------------------------- /autogen.sh: -------------------------------------------------------------------------------- 1 | #!/bin/sh 2 | 3 | set -ex 4 | mkdir -p m4 5 | rm -rf autom4te.cache aclocal.m4 6 | find . -name "Makefile.in" -exec rm {} \; 7 | aclocal --force 8 | 9 | # GNU libtool is named differently on some systems. This code tries several 10 | # variants like glibtoolize (MacOSX) and libtoolize1x (FreeBSD) 11 | 12 | #set +ex 13 | #echo "Looking for a version of libtoolize (which can have different names)..." 14 | #libtoolize="" 15 | #for l in glibtoolize libtoolize15 libtoolize14 libtoolize ; do 16 | # $l --version > /dev/null 2>&1 17 | # if [ $? = 0 ]; then 18 | # libtoolize=$l 19 | # echo "Found $l" 20 | # break 21 | # fi 22 | # echo "Did not find $l" 23 | #done 24 | 25 | #if [ "x$libtoolize" = "x" ]; then 26 | # echo "Can't find libtoolize on your system" 27 | # exit 1 28 | #fi 29 | 30 | set -ex 31 | #$libtoolize -c -f 32 | autoreconf -i 33 | autoconf -f -W all,no-obsolete 34 | # autoheader -f -W all 35 | # automake -a -c -f -W all 36 | automake --add-missing --foreign --copy -c -W all 37 | 38 | rm -rf autom4te.cache 39 | exit 0 40 | -------------------------------------------------------------------------------- /configure.ac: -------------------------------------------------------------------------------- 1 | AC_PREREQ([2.63]) 2 | AC_INIT([timestretch], [1.0.0], [quaglia@dis.uniroma1.it,pellegrini@dis.uniroma1.it]) 3 | AM_INIT_AUTOMAKE([foreign subdir-objects]) 4 | AC_CONFIG_MACRO_DIR([m4]) 5 | 6 | # Preliminary check: are we on Linux? 7 | AC_CANONICAL_HOST 8 | AC_MSG_CHECKING([for supported host Operating System]) 9 | case $host_os in 10 | linux*) 11 | # Do something specific for linux 12 | AC_MSG_RESULT([yes, ${host_os}]) 13 | ;; 14 | *) 15 | #Default Case 16 | AC_MSG_RESULT([no, ${host_os}]) 17 | AC_MSG_ERROR([This module runs only on Linux]) 18 | ;; 19 | esac 20 | 21 | # Preliminary check: are we on x86? 22 | AC_MSG_CHECKING([for a supported CPU architecture]) 23 | case "${host_cpu}" in 24 | 25 | x86_64) 26 | AC_MSG_RESULT([yes, ${host_cpu}]) 27 | ;; 28 | 29 | *) 30 | AC_MSG_RESULT([no, ${host_cpu}]) 31 | AC_MSG_ERROR([Unsupported host architecture. Currently ROOT-Sim supports only x86_64 systems.]) 32 | ;; 33 | esac 34 | 35 | 36 | 37 | 38 | # Configure kernel module paths 39 | AC_SUBST([with_kernel], [`uname -r`]) 40 | AC_SUBST([with_kernel_mod], [/lib/modules/$with_kernel/extra]) 41 | AC_SUBST([KERNEL_SRC], [/lib/modules/$with_kernel/build]) 42 | AC_SUBST([KERNEL_MOD], [$with_kernel_mod]) 43 | 44 | # Checks for programs. 45 | AC_LANG([C]) 46 | AC_PROG_CC 47 | AC_PROG_INSTALL 48 | AC_PROG_MKDIR_P 49 | AC_PROG_LN_S 50 | AC_PROG_GREP 51 | AC_PROG_SED 52 | AC_PROG_RANLIB 53 | AC_PATH_PROG(RM, rm, /bin/rm, $PATH:/bin:/usr/bin:/usr/local/bin) 54 | 55 | 56 | 57 | # Get finish_task_switch in the current kernel 58 | AC_MSG_CHECKING([for finish_task_switch in the current kernel]) 59 | fts_line=$($GREP -n finish_task_switch /boot/System.map-$(uname -r) | $SED 's/:.*//') 60 | finish_task_switch=$($SED "${fts_line}q;d" /boot/System.map-$(uname -r) | $SED 's/ .*//') 61 | if test -z "$finish_task_switch"; then 62 | AC_MSG_ERROR([Address of finish_task_switch not found in kernel map]) 63 | fi 64 | AC_MSG_RESULT([found at 0x$finish_task_switch]) 65 | AC_SUBST([FTS_ADDR], [0x$finish_task_switch]) 66 | 67 | # Get function after finish_task_switch in the current kernel 68 | AC_MSG_CHECKING([the address of function next to finish_task_switch in the current kernel]) 69 | let fts_line=$fts_line+1 70 | finish_task_switch_next=$($SED "${fts_line}q;d" /boot/System.map-$(uname -r) | $SED 's/ .*//') 71 | if test -z "$finish_task_switch_next"; then 72 | AC_MSG_ERROR([Address of function aftr finish_task_switch not found in kernel map]) 73 | fi 74 | AC_MSG_RESULT([found at 0x$finish_task_switch_next]) 75 | AC_SUBST([FTS_ADDR_NEXT], [0x$finish_task_switch_next]) 76 | 77 | 78 | # Are kernel headers installed? 79 | AC_CHECK_HEADERS([linux/ioctl.h],, 80 | [AC_MSG_ERROR([You must install kernel-headers])]) 81 | 82 | # Final output 83 | AC_CONFIG_FILES([Makefile]) 84 | AC_OUTPUT 85 | -------------------------------------------------------------------------------- /module/Makefile: -------------------------------------------------------------------------------- 1 | obj-m := schedule.o 2 | schedule-objs := hook.o schedule-hook.o ld.o 3 | 4 | -------------------------------------------------------------------------------- /module/hook.S: -------------------------------------------------------------------------------- 1 | /** 2 | * Copyright (C) 2008-2015 HPDCS Group 3 | * http://www.dis.uniroma1.it/~hpdcs 4 | * 5 | * 6 | * This file is part of ROOT-Sim (ROme OpTimistic Simulator). 7 | * 8 | * ROOT-Sim is free software; you can redistribute it and/or modify it under the 9 | * terms of the GNU General Public License as published by the Free Software 10 | * Foundation; either version 3 of the License, or (at your option) any later 11 | * version. 12 | * 13 | * ROOT-Sim is distributed in the hope that it will be useful, but WITHOUT ANY 14 | * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR 15 | * A PARTICULAR PURPOSE. See the GNU General Public License for more details. 16 | * 17 | * You should have received a copy of the GNU General Public License along with 18 | * ROOT-Sim; if not, write to the Free Software Foundation, Inc., 19 | * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA 20 | * 21 | * @file hook.S 22 | * @brief This hook is dynamically attached to Linux Kernel's finish_task_switch 23 | * to call a module-provided function at the end of the reschedule operation. 24 | * @author Alessandro Pellegrini 25 | * @date February, 2016 26 | */ 27 | 28 | .file "preempt_callback.S" 29 | .extern the_hook 30 | .extern count 31 | .extern audit_counter 32 | 33 | 34 | .text 35 | .globl schedule_hook 36 | .type schedule_hook, @function 37 | .globl schedule_hook_2 38 | .type schedule_hook_2, @function 39 | .globl schedule_hook_end 40 | .type schedule_hook_end, @function 41 | .globl schedule_hook_patch_point 42 | .type schedule_hook_patch_point, @function 43 | .globl schedule_hook_patch_point_2 44 | .type schedule_hook_patch_point_2, @function 45 | 46 | 47 | schedule_hook: 48 | pushq %rax 49 | lock incl count(%rip) 50 | 51 | # This is here just for audit and could be commented out 52 | incl audit_counter(%rip) 53 | 54 | movq the_hook(%rip), %rax 55 | test %rax, %rax 56 | # jz .+4 # location counter points to jz. jz is 2 bytes, callq is 2 bytes. 57 | jz restore 58 | callq *%rax 59 | restore: 60 | popq %rax 61 | schedule_hook_patch_point: 62 | nop # Five nops to leave place to dynamically patch this function 63 | nop 64 | nop 65 | nop 66 | nop 67 | nop 68 | nop 69 | nop 70 | nop 71 | nop 72 | lock decl count(%rip) 73 | ret 74 | schedule_hook_2: 75 | lock incl count(%rip) 76 | 77 | # This is here just for audit and could be commented out 78 | incl audit_counter(%rip) 79 | 80 | movq the_hook(%rip), %rax 81 | test %rax, %rax 82 | jz .+4 # location counter points to jz. jz is 2 bytes, callq is 2 bytes. 83 | callq *%rax 84 | schedule_hook_patch_point_2: 85 | nop # Five nops to leave place to dynamically patch this function 86 | nop 87 | nop 88 | nop 89 | nop 90 | nop 91 | nop 92 | nop 93 | nop 94 | nop 95 | lock decl count(%rip) 96 | ret 97 | schedule_hook_3: 98 | lock incl count(%rip) 99 | 100 | # This is here just for audit and could be commented out 101 | incl audit_counter(%rip) 102 | 103 | movq the_hook(%rip), %rax 104 | test %rax, %rax 105 | jz .+4 # location counter points to jz. jz is 2 bytes, callq is 2 bytes. 106 | callq *%rax 107 | schedule_hook_patch_point_3: 108 | nop # Five nops to leave place to dynamically patch this function 109 | nop 110 | nop 111 | nop 112 | nop 113 | nop 114 | nop 115 | nop 116 | nop 117 | nop 118 | lock decl count(%rip) 119 | ret 120 | schedule_hook_4: 121 | lock incl count(%rip) 122 | 123 | # This is here just for audit and could be commented out 124 | incl audit_counter(%rip) 125 | 126 | movq the_hook(%rip), %rax 127 | test %rax, %rax 128 | jz .+4 # location counter points to jz. jz is 2 bytes, callq is 2 bytes. 129 | callq *%rax 130 | schedule_hook_patch_point_4: 131 | nop # Five nops to leave place to dynamically patch this function 132 | nop 133 | nop 134 | nop 135 | nop 136 | nop 137 | nop 138 | nop 139 | nop 140 | nop 141 | lock decl count(%rip) 142 | ret 143 | schedule_hook_5: 144 | lock incl count(%rip) 145 | 146 | # This is here just for audit and could be commented out 147 | incl audit_counter(%rip) 148 | 149 | movq the_hook(%rip), %rax 150 | test %rax, %rax 151 | jz .+4 # location counter points to jz. jz is 2 bytes, callq is 2 bytes. 152 | callq *%rax 153 | schedule_hook_patch_point_5: 154 | nop # Five nops to leave place to dynamically patch this function 155 | nop 156 | nop 157 | nop 158 | nop 159 | nop 160 | nop 161 | nop 162 | nop 163 | nop 164 | lock decl count(%rip) 165 | ret 166 | schedule_hook_6: 167 | lock incl count(%rip) 168 | 169 | # This is here just for audit and could be commented out 170 | incl audit_counter(%rip) 171 | 172 | movq the_hook(%rip), %rax 173 | test %rax, %rax 174 | jz .+4 # location counter points to jz. jz is 2 bytes, callq is 2 bytes. 175 | callq *%rax 176 | schedule_hook_patch_point_6: 177 | nop # Five nops to leave place to dynamically patch this function 178 | nop 179 | nop 180 | nop 181 | nop 182 | nop 183 | nop 184 | nop 185 | nop 186 | nop 187 | lock decl count(%rip) 188 | ret 189 | schedule_hook_7: 190 | lock incl count(%rip) 191 | 192 | # This is here just for audit and could be commented out 193 | incl audit_counter(%rip) 194 | 195 | movq the_hook(%rip), %rax 196 | test %rax, %rax 197 | jz .+4 # location counter points to jz. jz is 2 bytes, callq is 2 bytes. 198 | callq *%rax 199 | schedule_hook_patch_point_7: 200 | nop # Five nops to leave place to dynamically patch this function 201 | nop 202 | nop 203 | nop 204 | nop 205 | nop 206 | nop 207 | nop 208 | nop 209 | nop 210 | lock decl count(%rip) 211 | ret 212 | schedule_hook_8: 213 | lock incl count(%rip) 214 | 215 | # This is here just for audit and could be commented out 216 | incl audit_counter(%rip) 217 | 218 | movq the_hook(%rip), %rax 219 | test %rax, %rax 220 | jz .+4 # location counter points to jz. jz is 2 bytes, callq is 2 bytes. 221 | callq *%rax 222 | schedule_hook_patch_point_8: 223 | nop # Five nops to leave place to dynamically patch this function 224 | nop 225 | nop 226 | nop 227 | nop 228 | nop 229 | nop 230 | nop 231 | nop 232 | nop 233 | lock decl count(%rip) 234 | ret 235 | schedule_hook_9: 236 | lock incl count(%rip) 237 | 238 | # This is here just for audit and could be commented out 239 | incl audit_counter(%rip) 240 | 241 | movq the_hook(%rip), %rax 242 | test %rax, %rax 243 | jz .+4 # location counter points to jz. jz is 2 bytes, callq is 2 bytes. 244 | callq *%rax 245 | schedule_hook_patch_point_9: 246 | nop # Five nops to leave place to dynamically patch this function 247 | nop 248 | nop 249 | nop 250 | nop 251 | nop 252 | nop 253 | nop 254 | nop 255 | nop 256 | lock decl count(%rip) 257 | ret 258 | schedule_hook_10: 259 | lock incl count(%rip) 260 | 261 | # This is here just for audit and could be commented out 262 | incl audit_counter(%rip) 263 | 264 | movq the_hook(%rip), %rax 265 | test %rax, %rax 266 | jz .+4 # location counter points to jz. jz is 2 bytes, callq is 2 bytes. 267 | callq *%rax 268 | schedule_hook_patch_point_10: 269 | nop # Five nops to leave place to dynamically patch this function 270 | nop 271 | nop 272 | nop 273 | nop 274 | nop 275 | nop 276 | nop 277 | nop 278 | nop 279 | lock decl count(%rip) 280 | ret 281 | schedule_hook_11: 282 | lock incl count(%rip) 283 | 284 | # This is here just for audit and could be commented out 285 | incl audit_counter(%rip) 286 | 287 | movq the_hook(%rip), %rax 288 | test %rax, %rax 289 | jz .+4 # location counter points to jz. jz is 2 bytes, callq is 2 bytes. 290 | callq *%rax 291 | schedule_hook_patch_point_11: 292 | nop # Five nops to leave place to dynamically patch this function 293 | nop 294 | nop 295 | nop 296 | nop 297 | nop 298 | nop 299 | nop 300 | nop 301 | nop 302 | lock decl count(%rip) 303 | ret 304 | schedule_hook_12: 305 | lock incl count(%rip) 306 | 307 | # This is here just for audit and could be commented out 308 | incl audit_counter(%rip) 309 | 310 | movq the_hook(%rip), %rax 311 | test %rax, %rax 312 | jz .+4 # location counter points to jz. jz is 2 bytes, callq is 2 bytes. 313 | callq *%rax 314 | schedule_hook_patch_point_12: 315 | nop # Five nops to leave place to dynamically patch this function 316 | nop 317 | nop 318 | nop 319 | nop 320 | nop 321 | nop 322 | nop 323 | nop 324 | nop 325 | lock decl count(%rip) 326 | ret 327 | schedule_hook_13: 328 | lock incl count(%rip) 329 | 330 | # This is here just for audit and could be commented out 331 | incl audit_counter(%rip) 332 | 333 | movq the_hook(%rip), %rax 334 | test %rax, %rax 335 | jz .+4 # location counter points to jz. jz is 2 bytes, callq is 2 bytes. 336 | callq *%rax 337 | schedule_hook_patch_point_13: 338 | nop # Five nops to leave place to dynamically patch this function 339 | nop 340 | nop 341 | nop 342 | nop 343 | nop 344 | nop 345 | nop 346 | nop 347 | nop 348 | lock decl count(%rip) 349 | ret 350 | schedule_hook_14: 351 | lock incl count(%rip) 352 | 353 | # This is here just for audit and could be commented out 354 | incl audit_counter(%rip) 355 | 356 | movq the_hook(%rip), %rax 357 | test %rax, %rax 358 | jz .+4 # location counter points to jz. jz is 2 bytes, callq is 2 bytes. 359 | callq *%rax 360 | schedule_hook_patch_point_14: 361 | nop # Five nops to leave place to dynamically patch this function 362 | nop 363 | nop 364 | nop 365 | nop 366 | nop 367 | nop 368 | nop 369 | nop 370 | nop 371 | lock decl count(%rip) 372 | ret 373 | schedule_hook_15: 374 | lock incl count(%rip) 375 | 376 | # This is here just for audit and could be commented out 377 | incl audit_counter(%rip) 378 | 379 | movq the_hook(%rip), %rax 380 | test %rax, %rax 381 | jz .+4 # location counter points to jz. jz is 2 bytes, callq is 2 bytes. 382 | callq *%rax 383 | schedule_hook_patch_point_15: 384 | nop # Five nops to leave place to dynamically patch this function 385 | nop 386 | nop 387 | nop 388 | nop 389 | nop 390 | nop 391 | nop 392 | nop 393 | nop 394 | lock decl count(%rip) 395 | ret 396 | schedule_hook_16: 397 | lock incl count(%rip) 398 | 399 | # This is here just for audit and could be commented out 400 | incl audit_counter(%rip) 401 | 402 | movq the_hook(%rip), %rax 403 | test %rax, %rax 404 | jz .+4 # location counter points to jz. jz is 2 bytes, callq is 2 bytes. 405 | callq *%rax 406 | schedule_hook_patch_point_16: 407 | nop # Five nops to leave place to dynamically patch this function 408 | nop 409 | nop 410 | nop 411 | nop 412 | nop 413 | nop 414 | nop 415 | nop 416 | nop 417 | lock decl count(%rip) 418 | ret 419 | schedule_hook_17: 420 | lock incl count(%rip) 421 | 422 | # This is here just for audit and could be commented out 423 | incl audit_counter(%rip) 424 | 425 | movq the_hook(%rip), %rax 426 | test %rax, %rax 427 | jz .+4 # location counter points to jz. jz is 2 bytes, callq is 2 bytes. 428 | callq *%rax 429 | schedule_hook_patch_point_17: 430 | nop # Five nops to leave place to dynamically patch this function 431 | nop 432 | nop 433 | nop 434 | nop 435 | nop 436 | nop 437 | nop 438 | nop 439 | nop 440 | lock decl count(%rip) 441 | ret 442 | schedule_hook_18: 443 | lock incl count(%rip) 444 | 445 | # This is here just for audit and could be commented out 446 | incl audit_counter(%rip) 447 | 448 | movq the_hook(%rip), %rax 449 | test %rax, %rax 450 | jz .+4 # location counter points to jz. jz is 2 bytes, callq is 2 bytes. 451 | callq *%rax 452 | schedule_hook_patch_point_18: 453 | nop # Five nops to leave place to dynamically patch this function 454 | nop 455 | nop 456 | nop 457 | nop 458 | nop 459 | nop 460 | nop 461 | nop 462 | nop 463 | lock decl count(%rip) 464 | ret 465 | schedule_hook_19: 466 | lock incl count(%rip) 467 | 468 | # This is here just for audit and could be commented out 469 | incl audit_counter(%rip) 470 | 471 | movq the_hook(%rip), %rax 472 | test %rax, %rax 473 | jz .+4 # location counter points to jz. jz is 2 bytes, callq is 2 bytes. 474 | callq *%rax 475 | schedule_hook_patch_point_19: 476 | nop # Five nops to leave place to dynamically patch this function 477 | nop 478 | nop 479 | nop 480 | nop 481 | nop 482 | nop 483 | nop 484 | nop 485 | nop 486 | lock decl count(%rip) 487 | ret 488 | schedule_hook_20: 489 | lock incl count(%rip) 490 | 491 | # This is here just for audit and could be commented out 492 | incl audit_counter(%rip) 493 | 494 | movq the_hook(%rip), %rax 495 | test %rax, %rax 496 | jz .+4 # location counter points to jz. jz is 2 bytes, callq is 2 bytes. 497 | callq *%rax 498 | schedule_hook_patch_point_20: 499 | nop # Five nops to leave place to dynamically patch this function 500 | nop 501 | nop 502 | nop 503 | nop 504 | nop 505 | nop 506 | nop 507 | nop 508 | nop 509 | lock decl count(%rip) 510 | ret 511 | schedule_hook_end: 512 | nop 513 | -------------------------------------------------------------------------------- /module/ld.c: -------------------------------------------------------------------------------- 1 | /* 2 | x86 Length Disassembler. 3 | Copyright (C) 2016 Alessandro Pellegrini 4 | Copyright (C) 2013 Byron Platt 5 | 6 | This program is free software: you can redistribute it and/or modify 7 | it under the terms of the GNU General Public License as published by 8 | the Free Software Foundation, either version 3 of the License, or 9 | (at your option) any later version. 10 | 11 | This program is distributed in the hope that it will be useful, 12 | but WITHOUT ANY WARRANTY; without even the implied warranty of 13 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 | GNU General Public License for more details. 15 | 16 | You should have received a copy of the GNU General Public License 17 | along with this program. If not, see . 18 | */ 19 | #include 20 | 21 | #include "lend.h" 22 | #include "ld.h" 23 | 24 | //__thread bool _rip_relative; 25 | bool _rip_relative; 26 | 27 | /* length_disasm */ 28 | unsigned int length_disasm(void *opcode0, char mode) { 29 | unsigned char *opcode = opcode0; 30 | 31 | unsigned int flag = 0; 32 | unsigned int ddef = 4, mdef = 4; 33 | unsigned int msize = 0, dsize = 0; 34 | 35 | unsigned char first_op, op, modrm, mod, rm, rex = 0; 36 | unsigned char multibyte = 0; 37 | 38 | _rip_relative = false; 39 | 40 | prefix: 41 | op = *opcode++; 42 | 43 | /* prefix */ 44 | if (CHECK_PREFIX(op)) { 45 | if (CHECK_PREFIX_66(op)) ddef = 2; 46 | else if (CHECK_PREFIX_67(op)) mdef = 2; 47 | goto prefix; 48 | } 49 | 50 | /* Possible REX prefixes, which come after legacy prefixes. 51 | * Moreover, multiple REX prefixes could be present. Although the behaviour should 52 | * be undefined, most CPUs consider only the last one. */ 53 | if (mode == MODE_X64 && CHECK_REX(op)) { 54 | rex = op; 55 | goto prefix; 56 | } 57 | 58 | first_op = op; 59 | 60 | /* two and three byte opcode */ 61 | if (CHECK_0F(op)) { 62 | op = *opcode++; 63 | multibyte = 1; 64 | 65 | /* Three-byte 38 table */ 66 | if(CHECK_38(op)) { 67 | op = *opcode++; 68 | if(CHECK_MODRM38(op)) flag++; 69 | } else 70 | 71 | /* Three-byte 3A table */ 72 | if(CHECK_3A(op)) { 73 | op = *opcode++; 74 | if(CHECK_MODRM3A(op)) flag++; 75 | } 76 | 77 | /* Two-byte table */ 78 | else { 79 | if (CHECK_MODRM2(op)) flag++; 80 | if (CHECK_DATA12(op)) dsize++; 81 | if (CHECK_DATA662(op)) dsize += ddef; 82 | } 83 | } 84 | 85 | /* one byte opcode */ 86 | else { 87 | if (CHECK_MODRM(op)) flag++; 88 | if (CHECK_TEST(op) && !(*opcode & 0x38)) dsize += (op & 1) ? ddef : 1; 89 | if (CHECK_DATA1(op)) dsize++; 90 | if (CHECK_DATA2(op)) dsize += 2; 91 | if (CHECK_DATA66(op)) dsize += ddef; 92 | if (CHECK_MEM67(op)) msize += mdef; 93 | } 94 | 95 | /* modrm */ 96 | if (flag) { 97 | modrm = *opcode++; 98 | mod = modrm & 0xc0; 99 | rm = modrm & 0x07; 100 | 101 | if (mod != 0xc0) { 102 | if (mod == 0x40) msize++; 103 | if (mod == 0x80) msize += mdef; 104 | if (mdef == 2 && mode == MODE_X32) { 105 | if ((mod == 0x00) && (rm == 0x06)) msize += 2; 106 | } else { 107 | if (rm == 0x04) { 108 | rm = *opcode++ & 0x07; /* rm is the sib */ 109 | } 110 | if (rm == 0x05 && mod == 0x00) { 111 | if(mdef == 2) msize += 2; 112 | else msize += 4; 113 | } 114 | } 115 | if(mode == MODE_X64 && first_op != 0xff && mod == 0x00 && rm == 0x05) { 116 | _rip_relative = true; 117 | } 118 | 119 | } else { 120 | if(op == 0x70) { /* TODO: need another table here! */ 121 | /* Three operands instruction (SSE extension) */ 122 | dsize = 1; 123 | } 124 | } 125 | } 126 | 127 | /* REX.W causes 66h to be ignored */ 128 | if (CHECK_REXW(rex) && !multibyte) { 129 | if(CHECK_IMM64(op)) dsize = 8; 130 | if(CHECK_OFF64(op)) msize = 8; 131 | } 132 | 133 | opcode += msize + dsize; 134 | 135 | return opcode - (unsigned char *)opcode0; 136 | } 137 | -------------------------------------------------------------------------------- /module/ld.h: -------------------------------------------------------------------------------- 1 | /* 2 | x86 Length Disassembler. 3 | Copyright (C) 2016 Alessandro Pellegrini 4 | Copyright (C) 2013 Byron Platt 5 | 6 | This program is free software: you can redistribute it and/or modify 7 | it under the terms of the GNU General Public License as published by 8 | the Free Software Foundation, either version 3 of the License, or 9 | (at your option) any later version. 10 | 11 | This program is distributed in the hope that it will be useful, 12 | but WITHOUT ANY WARRANTY; without even the implied warranty of 13 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 | GNU General Public License for more details. 15 | 16 | You should have received a copy of the GNU General Public License 17 | along with this program. If not, see . 18 | */ 19 | 20 | #pragma once 21 | 22 | /* table macros */ 23 | #define BITMASK32( \ 24 | b00,b01,b02,b03,b04,b05,b06,b07, \ 25 | b08,b09,b0a,b0b,b0c,b0d,b0e,b0f, \ 26 | b10,b11,b12,b13,b14,b15,b16,b17, \ 27 | b18,b19,b1a,b1b,b1c,b1d,b1e,b1f \ 28 | ) ( \ 29 | (b00<<0x00)|(b01<<0x01)|(b02<<0x02)|(b03<<0x03)| \ 30 | (b04<<0x04)|(b05<<0x05)|(b06<<0x06)|(b07<<0x07)| \ 31 | (b08<<0x08)|(b09<<0x09)|(b0a<<0x0a)|(b0b<<0x0b)| \ 32 | (b0c<<0x0c)|(b0d<<0x0d)|(b0e<<0x0e)|(b0f<<0x0f)| \ 33 | (b10<<0x10)|(b11<<0x11)|(b12<<0x12)|(b13<<0x13)| \ 34 | (b14<<0x14)|(b15<<0x15)|(b16<<0x16)|(b17<<0x17)| \ 35 | (b18<<0x18)|(b19<<0x19)|(b1a<<0x1a)|(b1b<<0x1b)| \ 36 | (b1c<<0x1c)|(b1d<<0x1d)|(b1e<<0x1e)|(b1f<<0x1f) \ 37 | ) 38 | #define CHECK_TABLE(t, v) ((t[(v)>>5]>>((v)&0x1f))&1) 39 | 40 | /* CHECK_PREFIX */ 41 | const static unsigned int prefix_t[] = { 42 | /* 0 1 2 3 4 5 6 7 8 9 a b c d e f */ 43 | BITMASK32(0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0, /* 0 */ 44 | 0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0), /* 1 */ 45 | BITMASK32(0,0,0,0,0,0,1,0, 0,0,0,0,0,0,1,0, /* 2 */ 46 | 0,0,0,0,0,0,1,0, 0,0,0,0,0,0,1,0), /* 3 */ 47 | BITMASK32(0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0, /* 4 */ 48 | 0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0), /* 5 */ 49 | BITMASK32(0,0,0,0,1,1,1,1, 0,0,0,0,0,0,0,0, /* 6 */ 50 | 0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0), /* 7 */ 51 | BITMASK32(0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0, /* 8 */ 52 | 0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0), /* 9 */ 53 | BITMASK32(0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0, /* a */ 54 | 0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0), /* b */ 55 | BITMASK32(0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0, /* c */ 56 | 0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0), /* d */ 57 | BITMASK32(0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0, /* e */ 58 | 1,0,1,1,0,0,0,0, 0,0,0,0,0,0,0,0) /* f */ 59 | }; 60 | #define CHECK_PREFIX(v) CHECK_TABLE(prefix_t, v) 61 | 62 | /* x64 REX prefix handling */ 63 | #define CHECK_REX(v) (((v)>>4)==0x4) 64 | #define CHECK_REXW(v) ((v)&0x08) 65 | 66 | /* Check for movs which handle imm64 */ 67 | #define CHECK_IMM64(v) (((v)&0xf8)==0xb8) 68 | 69 | /* Check for movs which handles moffs64 */ 70 | #define CHECK_OFF64(v) ((v)==0xa1) 71 | 72 | /* CHECK_PREFIX_66 */ 73 | #define CHECK_PREFIX_66(v) ((v)==0x66) 74 | 75 | /* CHECK_PREFIX_67 */ 76 | #define CHECK_PREFIX_67(v) ((v)==0x67) 77 | 78 | /* CHECK_0F */ 79 | #define CHECK_0F(v) ((v)==0x0f) 80 | 81 | /* CHECK_38 */ 82 | #define CHECK_38(v) ((v)==0x38) 83 | 84 | /* CHECK_3A */ 85 | #define CHECK_3A(v) ((v)==0x3a) 86 | 87 | /* CHECK_MODRM3A */ 88 | const static unsigned int modrm3a_t[] = { 89 | /* 0 1 2 3 4 5 6 7 8 9 a b c d e f */ 90 | BITMASK32(1,1,1,1,1,1,1,1, 1,1,1,1,1,1,1,1, /* 0 */ 91 | 0,0,0,0,1,1,1,1, 1,1,1,1,0,1,1,1), /* 1 */ 92 | BITMASK32(1,1,1,1,1,1,1,1, 0,0,0,0,0,0,0,0, /* 2 */ 93 | 1,1,1,1,0,0,0,0, 1,1,1,1,0,1,1,1), /* 3 */ 94 | BITMASK32(1,1,1,1,1,0,1,0, 1,1,1,1,1,0,0,0, /* 4 */ 95 | 1,1,1,0,1,1,1,1, 0,0,0,0,1,1,1,1), /* 5 */ 96 | BITMASK32(1,1,1,1,0,0,1,1, 1,1,1,1,1,1,1,1, /* 6 */ 97 | 0,0,0,0,0,0,0,0, 1,1,1,1,1,1,1,1), /* 7 */ 98 | BITMASK32(0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0, /* 8 */ 99 | 0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0), /* 9 */ 100 | BITMASK32(0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0, /* a */ 101 | 0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0), /* b */ 102 | BITMASK32(0,0,0,0,0,0,0,0, 0,0,1,1,1,0,0,0, /* c */ 103 | 0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,1), /* d */ 104 | BITMASK32(0,0,0,0,0,0,1,0, 0,0,0,0,0,0,0,0, /* e */ 105 | 1,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0) /* f */ 106 | }; 107 | #define CHECK_MODRM3A(v) CHECK_TABLE(modrm3a_t, v) 108 | 109 | /* CHECK_MODRM38 */ 110 | const static unsigned int modrm38_t[] = { 111 | /* 0 1 2 3 4 5 6 7 8 9 a b c d e f */ 112 | BITMASK32(1,1,1,1,1,1,1,1, 1,1,1,1,1,1,1,1, /* 0 */ 113 | 1,1,1,1,1,1,1,1, 1,1,1,1,1,1,1,1), /* 1 */ 114 | BITMASK32(1,1,1,1,1,1,1,1, 1,1,1,1,1,1,1,1, /* 2 */ 115 | 1,1,1,1,1,1,1,1, 1,1,1,1,1,1,1,1), /* 3 */ 116 | BITMASK32(1,1,1,1,1,1,1,1, 0,0,0,0,1,1,1,1, /* 4 */ 117 | 1,1,1,1,0,1,0,0, 1,1,1,1,1,1,1,1), /* 5 */ 118 | BITMASK32(0,0,0,0,1,1,1,0, 0,0,0,0,1,1,1,1, /* 6 */ 119 | 0,0,0,0,1,1,1,1, 1,1,1,1,1,1,1,1), /* 7 */ 120 | BITMASK32(1,1,1,1,1,0,1,1, 1,1,1,1,1,1,1,1, /* 8 */ 121 | 1,1,1,1,0,0,1,1, 1,1,1,1,1,1,1,1), /* 9 */ 122 | BITMASK32(1,1,1,1,1,0,1,1, 1,1,1,1,1,1,1,1, /* a */ 123 | 0,0,0,0,1,1,1,1, 1,1,1,1,1,1,1,1), /* b */ 124 | BITMASK32(0,0,0,0,0,1,1,1, 1,1,1,1,1,1,0,0, /* c */ 125 | 1,1,0,0,1,1,0,0, 0,0,0,1,1,1,1,1), /* d */ 126 | BITMASK32(0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0, /* e */ 127 | 1,1,1,1,0,1,1,1, 0,0,0,0,0,0,0,0) /* f */ 128 | }; 129 | #define CHECK_MODRM38(v) CHECK_TABLE(modrm38_t, v) 130 | 131 | /* CHECK_MODRM2 */ 132 | const static unsigned int modrm2_t[] = { 133 | /* 0 1 2 3 4 5 6 7 8 9 a b c d e f */ 134 | BITMASK32(1,1,1,1,0,0,0,0, 0,0,0,0,0,0,0,0, /* 0 */ 135 | 1,1,1,1,1,1,1,1, 1,1,1,1,1,1,1,1), /* 1 */ 136 | BITMASK32(1,1,1,1,0,0,0,0, 1,1,1,1,1,1,1,1, /* 2 */ 137 | 0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0), /* 3 */ 138 | BITMASK32(1,1,1,1,1,1,1,1, 1,1,1,1,1,1,1,1, /* 4 */ 139 | 1,1,1,1,1,1,1,1, 1,1,1,1,1,1,1,1), /* 5 */ 140 | BITMASK32(1,1,1,1,1,1,1,1, 1,1,1,1,1,1,1,1, /* 6 */ 141 | 1,0,0,0,1,1,1,0, 1,1,0,0,1,1,1,1), /* 7 */ 142 | BITMASK32(0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0, /* 8 */ 143 | 1,1,1,1,1,1,1,1, 1,1,1,1,1,1,1,1), /* 9 */ 144 | BITMASK32(0,0,0,1,1,1,0,0, 0,0,0,1,1,1,0,1, /* a */ 145 | 1,1,1,1,1,1,1,1, 1,0,1,1,1,1,1,1), /* b */ 146 | BITMASK32(1,1,1,1,1,1,1,0, 0,0,0,0,0,0,0,0, /* c */ 147 | 1,1,1,1,1,1,1,1, 1,1,1,1,1,1,1,1), /* d */ 148 | BITMASK32(1,1,1,1,1,1,1,1, 1,1,1,1,1,1,1,1, /* e */ 149 | 1,1,1,1,1,1,1,1, 1,1,1,1,1,1,1,1) /* f */ 150 | }; 151 | #define CHECK_MODRM2(v) CHECK_TABLE(modrm2_t, v) 152 | 153 | /* CHECK_DATA12 */ 154 | #define CHECK_DATA12(v) ((v)==0xa4||(v)==0xac||(v)==0xba) 155 | 156 | /* CHECK_DATA662 */ 157 | #define CHECK_DATA662(v) (((v)&0xf0)==0x80) 158 | 159 | /* CHECK_MODRM */ 160 | const static unsigned int modrm_t[] = { 161 | /* 0 1 2 3 4 5 6 7 8 9 a b c d e f */ 162 | BITMASK32(1,1,1,1,0,0,0,0, 1,1,1,1,0,0,0,0, /* 0 */ 163 | 1,1,1,1,0,0,0,0, 1,1,1,1,0,0,0,0), /* 1 */ 164 | BITMASK32(1,1,1,1,0,0,0,0, 1,1,1,1,0,0,0,0, /* 2 */ 165 | 1,1,1,1,0,0,0,0, 1,1,1,1,0,0,0,0), /* 3 */ 166 | BITMASK32(0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0, /* 4 */ 167 | 0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0), /* 5 */ 168 | BITMASK32(0,0,1,1,0,0,0,0, 0,1,0,1,0,0,0,0, /* 6 */ 169 | 0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0), /* 7 */ 170 | BITMASK32(1,1,1,1,1,1,1,1, 1,1,1,1,1,1,1,1, /* 8 */ 171 | 0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0), /* 9 */ 172 | BITMASK32(0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0, /* a */ 173 | 0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0), /* b */ 174 | BITMASK32(1,1,0,0,1,1,1,1, 0,0,0,0,0,0,0,0, /* c */ 175 | 1,1,1,1,0,0,0,0, 1,1,1,1,1,1,1,1), /* d */ 176 | BITMASK32(0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0, /* e */ 177 | 0,0,0,0,0,0,1,1, 0,0,0,0,0,0,1,1) /* f */ 178 | }; 179 | #define CHECK_MODRM(v) CHECK_TABLE(modrm_t, v) 180 | 181 | /* CHECK_TEST */ 182 | #define CHECK_TEST(v) ((v)==0xf6||(v)==0xf7) 183 | 184 | /* CHECK_DATA1 */ 185 | const static unsigned int data1_t[] = { 186 | /* 0 1 2 3 4 5 6 7 8 9 a b c d e f */ 187 | BITMASK32(0,0,0,0,1,0,0,0, 0,0,0,0,1,0,0,0, /* 0 */ 188 | 0,0,0,0,1,0,0,0, 0,0,0,0,1,0,0,0), /* 1 */ 189 | BITMASK32(0,0,0,0,1,0,0,0, 0,0,0,0,1,0,0,0, /* 2 */ 190 | 0,0,0,0,1,0,0,0, 0,0,0,0,1,0,0,0), /* 3 */ 191 | BITMASK32(0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0, /* 4 */ 192 | 0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0), /* 5 */ 193 | BITMASK32(0,0,0,0,0,0,0,0, 0,0,1,1,0,0,0,0, /* 6 */ 194 | 1,1,1,1,1,1,1,1, 1,1,1,1,1,1,1,1), /* 7 */ 195 | BITMASK32(1,0,1,1,0,0,0,0, 0,0,0,0,0,0,0,0, /* 8 */ 196 | 0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0), /* 9 */ 197 | BITMASK32(0,0,0,0,0,0,0,0, 1,0,0,0,0,0,0,0, /* a */ 198 | 1,1,1,1,1,1,1,1, 0,0,0,0,0,0,0,0), /* b */ 199 | BITMASK32(1,1,0,0,0,0,1,0, 1,0,0,0,0,1,0,0, /* c */ 200 | 0,0,0,0,1,1,0,0, 0,0,0,0,0,0,0,0), /* d */ 201 | BITMASK32(1,1,1,1,1,1,1,1, 0,0,0,1,0,0,0,0, /* e */ 202 | 0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0) /* f */ 203 | }; 204 | #define CHECK_DATA1(v) CHECK_TABLE(data1_t, v) 205 | 206 | /* CHECK_DATA2 */ 207 | const static unsigned int data2_t[] = { 208 | /* 0 1 2 3 4 5 6 7 8 9 a b c d e f */ 209 | BITMASK32(0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0, /* 0 */ 210 | 0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0), /* 1 */ 211 | BITMASK32(0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0, /* 2 */ 212 | 0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0), /* 3 */ 213 | BITMASK32(0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0, /* 4 */ 214 | 0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0), /* 5 */ 215 | BITMASK32(0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0, /* 6 */ 216 | 0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0), /* 7 */ 217 | BITMASK32(0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0, /* 8 */ 218 | 0,0,0,0,0,0,0,0, 0,0,1,0,0,0,0,0), /* 9 */ 219 | BITMASK32(0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0, /* a */ 220 | 0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0), /* b */ 221 | BITMASK32(0,0,1,0,0,0,0,0, 1,0,1,0,0,0,0,0, /* c */ 222 | 0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0), /* d */ 223 | BITMASK32(0,0,0,0,0,0,0,0, 0,0,1,0,0,0,0,0, /* e */ 224 | 0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0) /* f */ 225 | }; 226 | #define CHECK_DATA2(v) CHECK_TABLE(data2_t, v) 227 | 228 | /* CHECK_DATA66 */ 229 | const static unsigned int data66_t[] = { 230 | /* 0 1 2 3 4 5 6 7 8 9 a b c d e f */ 231 | BITMASK32(0,0,0,0,0,1,0,0, 0,0,0,0,0,1,0,0, /* 0 */ 232 | 0,0,0,0,0,1,0,0, 0,0,0,0,0,1,0,0), /* 1 */ 233 | BITMASK32(0,0,0,0,0,1,0,0, 0,0,0,0,0,1,0,0, /* 2 */ 234 | 0,0,0,0,0,1,0,0, 0,0,0,0,0,1,0,0), /* 3 */ 235 | BITMASK32(0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0, /* 4 */ 236 | 0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0), /* 5 */ 237 | BITMASK32(0,0,0,0,0,0,0,0, 1,1,0,0,0,0,0,0, /* 6 */ 238 | 0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0), /* 7 */ 239 | BITMASK32(0,1,0,0,0,0,0,0, 0,0,0,0,0,0,0,0, /* 8 */ 240 | 0,0,0,0,0,0,0,0, 0,0,1,0,0,0,0,0), /* 9 */ 241 | BITMASK32(0,0,0,0,0,0,0,0, 0,1,0,0,0,0,0,0, /* a */ 242 | 0,0,0,0,0,0,0,0, 1,1,1,1,1,1,1,1), /* b */ 243 | BITMASK32(0,0,0,0,0,0,0,1, 0,0,0,0,0,0,0,0, /* c */ 244 | 0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0), /* d */ 245 | BITMASK32(0,0,0,0,0,0,0,0, 1,1,1,0,0,0,0,0, /* e */ 246 | 0,0,0,0,0,0,0,0, 0,0,0,0,0,0,0,0) /* f */ 247 | }; 248 | #define CHECK_DATA66(v) CHECK_TABLE(data66_t, v) 249 | 250 | /* CHECK_MEM67 */ 251 | #define CHECK_MEM67(v) (((v)&0xfc)==0xa0) 252 | -------------------------------------------------------------------------------- /module/lend.h: -------------------------------------------------------------------------------- 1 | /* 2 | x86 Length Disassembler. 3 | Copyright (C) 2016 Alessandro Pellegrini 4 | Copyright (C) 2013 Byron Platt 5 | 6 | This program is free software: you can redistribute it and/or modify 7 | it under the terms of the GNU General Public License as published by 8 | the Free Software Foundation, either version 3 of the License, or 9 | (at your option) any later version. 10 | 11 | This program is distributed in the hope that it will be useful, 12 | but WITHOUT ANY WARRANTY; without even the implied warranty of 13 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 | GNU General Public License for more details. 15 | 16 | You should have received a copy of the GNU General Public License 17 | along with this program. If not, see . 18 | */ 19 | 20 | #pragma once 21 | #include 22 | 23 | //extern __thread bool _rip_relative; 24 | extern bool _rip_relative; 25 | 26 | /* Switch between 32-bit and 64-bit implementations */ 27 | #define MODE_X32 1 28 | #define MODE_X64 2 29 | 30 | #define has_rip_relative() (_rip_relative == true) 31 | 32 | /* length_disasm */ 33 | unsigned int length_disasm(void *opcode0, char mode); 34 | -------------------------------------------------------------------------------- /module/schedule-hook.c: -------------------------------------------------------------------------------- 1 | /** Copyright (C) 2014-2015 HPDCS Group 2 | * http://www.dis.uniroma1.it/~hpdcs 3 | * 4 | * This is free software; 5 | * You can redistribute it and/or modify this file under the 6 | * terms of the GNU General Public License as published by the Free Software 7 | * Foundation; either version 3 of the License, or (at your option) any later 8 | * version. 9 | * 10 | * This file is distributed in the hope that it will be useful, but WITHOUT ANY 11 | * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR 12 | * A PARTICULAR PURPOSE. See the GNU General Public License for more details. 13 | * 14 | * You should have received a copy of the GNU General Public License along with 15 | * this file; if not, write to the Free Software Foundation, Inc., 16 | * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA 17 | * 18 | * @file schedule-hook.c 19 | * @brief This is the main source for the Linux Kernel Module which implements 20 | * a schedule-hook module allowing running a custom function each time a thread is cpu rescheduled 21 | * @author Francesco Quaglia 22 | * @author Alessandro Pellegrini 23 | * @author Emanuele De Santis 24 | * 25 | * @date October 15, 2015 26 | */ 27 | 28 | #define EXPORT_SYMTAB 29 | #include 30 | #include 31 | #include 32 | #include 33 | #include 34 | #include 35 | #include 36 | #include 37 | #include 38 | #include 39 | #include 40 | #include 41 | #include 42 | #include 43 | #include 44 | #include 45 | #include 46 | #include 47 | #include "ld.h" 48 | #include "lend.h" 49 | //#include 50 | //#include 51 | //#include 52 | 53 | // This gives access to read_cr0() and write_cr0() 54 | #if LINUX_VERSION_CODE > KERNEL_VERSION(3,3,0) 55 | #include 56 | #else 57 | #include 58 | #endif 59 | #ifndef X86_CR0_WP 60 | #define X86_CR0_WP 0x00010000 61 | #endif 62 | 63 | // This macro was added in kernel 3.5 64 | #if LINUX_VERSION_CODE < KERNEL_VERSION(3,5,0) 65 | #define APIC_EOI_ACK 0x0 /* Docs say 0 for future compat. */ 66 | #endif 67 | 68 | #include "schedule-hook.h" 69 | 70 | #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,25) 71 | #error Unsupported Kernel Version 72 | #endif 73 | 74 | 75 | 76 | #define DEBUG if(1) // change with 0 for removing module coded debug stuff 77 | #define DEBUG_SCHEDULE_HOOK if(1) // change with 0 for removing schedule_hook coded debug stuff 78 | 79 | 80 | 81 | unsigned long the_hook = 0; 82 | #define PERMISSION_MASK (S_IRUSR | S_IRGRP | S_IROTH) 83 | module_param(the_hook, ulong, PERMISSION_MASK); 84 | unsigned int audit_counter = 0; 85 | #define PERMISSION_MASK (S_IRUSR | S_IRGRP | S_IROTH) 86 | module_param(audit_counter, int, PERMISSION_MASK); 87 | 88 | static int bytes_to_patch_in_schedule = 5; 89 | 90 | static atomic_t synch_leave; 91 | static atomic_t synch_enter; 92 | 93 | atomic_t count ; 94 | atomic_t reference_count ; 95 | ulong phase = 0;//this is used to implement a phase based retry protocol for umounting this module 96 | 97 | static void synchronize_all_slaves(void *); 98 | static void schedule_hook_cleanup(void); 99 | static int schedule_hook_init(void); 100 | static void schedule_unpatch(void); 101 | static int schedule_patch(void); 102 | static void print_bytes(char *str, unsigned char *ptr, size_t s); 103 | static int check_patch_compatibility(void); 104 | extern void schedule_hook(void); 105 | extern void schedule_hook_2(void); 106 | 107 | MODULE_LICENSE("GPL"); 108 | MODULE_AUTHOR("Alessandro Pellegrini , Francesco Quaglia "); 109 | MODULE_DESCRIPTION("Run time patch of the Linux kernel scheduler for supporting the execution of a generic custom function upon thread reschedule"); 110 | module_init(schedule_hook_init); 111 | module_exit(schedule_unpatch); 112 | //module_exit(schedule_hook_cleanup); 113 | 114 | 115 | /* MODULE VARIABLES */ 116 | 117 | static unsigned char finish_task_switch_original_bytes[6]; 118 | void *finish_task_switch = (void *)FTS_ADDR; 119 | void *finish_task_switch_next = (void *)FTS_ADDR_NEXT; 120 | 121 | typedef struct backup{ 122 | char bytes[128]; 123 | void* init_addr; 124 | unsigned short int len; 125 | } backup_t; 126 | 127 | backup_t* b; 128 | 129 | unsigned short int backup_count=0; 130 | 131 | typedef struct instr { 132 | void* ptr; 133 | unsigned char bytecode[16]; 134 | short unsigned int size; 135 | } instr_t; 136 | 137 | 138 | // These are set in hook.S 139 | extern void schedule_hook_end(void); 140 | extern void schedule_hook_patch_point(void); 141 | extern void schedule_hook_patch_point_2(void); 142 | 143 | 144 | static void synchronize_all_slaves(void *info) { 145 | (void)info; 146 | 147 | printk(KERN_DEBUG "%s: cpu %d entering synchronize_all_slaves\n", KBUILD_MODNAME, smp_processor_id()); 148 | atomic_dec(&synch_enter); 149 | preempt_disable(); 150 | while(atomic_read(&synch_leave) > 0); 151 | preempt_enable(); 152 | printk(KERN_DEBUG "%s: cpu %d leaving synchronize_all_slaves\n", KBUILD_MODNAME, smp_processor_id()); 153 | } 154 | 155 | #define synchronize_all() do { \ 156 | printk("cpu %d asking from unpreemptive synchronization\n", smp_processor_id()); \ 157 | atomic_set(&synch_enter, num_online_cpus() - 1); \ 158 | atomic_set(&synch_leave, 1); \ 159 | preempt_disable(); \ 160 | smp_call_function_many(cpu_online_mask, synchronize_all_slaves, NULL, false); /* false because we manually synchronize */ \ 161 | while(atomic_read(&synch_enter) > 0); \ 162 | printk("cpu %d all kernel threads synchronized\n", smp_processor_id()); \ 163 | } while(0) 164 | 165 | #define unsynchronize_all() do { \ 166 | printk("cpu %d freeing other kernel threads\n", smp_processor_id()); \ 167 | atomic_set(&synch_leave, 0); \ 168 | preempt_enable(); \ 169 | } while(0) 170 | 171 | 172 | static void print_bytes(char *str, unsigned char *ptr, size_t s) { 173 | size_t i; 174 | 175 | printk(KERN_DEBUG "%s: %s: ", KBUILD_MODNAME, str); 176 | for(i = 0; i < s; i++) 177 | printk(KERN_CONT "%02x ", ptr[i]); 178 | printk(KERN_CONT "\n"); 179 | } 180 | 181 | static int check_patch_compatibility(void) { 182 | unsigned char *ptr; 183 | 184 | int matched = 0; 185 | int i; 186 | unsigned char magic[9] = {0x41, 0x58, 0x59, 0x5a, 0x5b, 0x5c, 0x5d, 0x5e, 0x5f}; 187 | int j = 0; 188 | 189 | print_bytes("Scheduler side - I will check the compatibility on these bytes", finish_task_switch, finish_task_switch_next - finish_task_switch); 190 | 191 | printk(KERN_DEBUG "%s: Scanning bytes backwards for magic matching ('-' are don't care bytes): ",KBUILD_MODNAME); 192 | ptr = (unsigned char *)finish_task_switch_next - 1; 193 | while((long)ptr >= (long)finish_task_switch) { 194 | 195 | if(*ptr != 0xc3) { 196 | printk(KERN_CONT "-"); 197 | ptr--; 198 | continue; 199 | } 200 | 201 | // Here we should have found the first (from the end of the function) ret 202 | // Check whether the pattern is one of: 203 | // pop pop ret 204 | // pop pop pop ret 205 | // pop pop pop pop ret 206 | for(j = -1; j >= -4; j--) { 207 | matched = 0; 208 | for(i = 0; i < 9; i++) { 209 | if(ptr[j] == magic[i]) { 210 | printk(KERN_CONT "%02x ", ptr[j]); 211 | matched = 1; 212 | break; 213 | } 214 | } 215 | if(!matched) 216 | break; 217 | } 218 | 219 | if(matched) { 220 | 221 | printk(KERN_CONT "\n"); 222 | if(ptr[j] == 0x41) { // Check for a REX prefix before the pop we stopped at 223 | printk(KERN_DEBUG "%s: first pop assumed to be one-byte, yet it's two-bytes. Self-correcting the patch.\n", KBUILD_MODNAME); 224 | bytes_to_patch_in_schedule = 5; 225 | ptr--; 226 | } 227 | 228 | // If the pattern is found, ptr must point to the first byte *after* the ret 229 | ptr++; 230 | break; 231 | } 232 | 233 | // We didn't find the pattern. Go on scanning backwards 234 | ptr--; 235 | 236 | } 237 | 238 | if(ptr == finish_task_switch) { 239 | printk(KERN_CONT "no valid ret instruction found in finish_task_switch\n"); 240 | goto failed; 241 | } 242 | 243 | // We've been lucky! Update the position where we are going to patch the schedule function 244 | finish_task_switch_next = ptr; 245 | 246 | if(bytes_to_patch_in_schedule > 4) { 247 | printk(KERN_CONT "%02x ", ((unsigned char *)finish_task_switch_next)[-5]); 248 | } 249 | printk(KERN_CONT "%02x %02x %02x %02x %02x looks correct.\n", 250 | ((unsigned char *)finish_task_switch_next)[-4], 251 | ((unsigned char *)finish_task_switch_next)[-3], 252 | ((unsigned char *)finish_task_switch_next)[-2], 253 | ((unsigned char *)finish_task_switch_next)[-1], 254 | ((unsigned char *)finish_task_switch_next)[-0]); 255 | 256 | printk(KERN_DEBUG "%s: total number of bytes to be patched is %d\n", KBUILD_MODNAME, bytes_to_patch_in_schedule); 257 | 258 | return 0; 259 | 260 | failed: 261 | 262 | printk(KERN_NOTICE "%s: magic check on bytes ", KBUILD_MODNAME); 263 | printk(KERN_CONT "%02x %02x %02x %02x %02x failed.\n", 264 | ((unsigned char *)finish_task_switch_next)[-4], 265 | ((unsigned char *)finish_task_switch_next)[-3], 266 | ((unsigned char *)finish_task_switch_next)[-2], 267 | ((unsigned char *)finish_task_switch_next)[-1], 268 | ((unsigned char *)finish_task_switch_next)[-0]); 269 | 270 | return -1; 271 | } 272 | 273 | 274 | 275 | static int schedule_patch(void) { 276 | 277 | int pos = 0; 278 | long displacement; 279 | int ret = 0; 280 | unsigned long cr0; 281 | unsigned char bytes_to_redirect[6]; 282 | int schedule_hook_length; 283 | int i=0; 284 | int j; 285 | void * temp; 286 | 287 | instr_t* v=(instr_t*) kmalloc(((unsigned char*)(finish_task_switch_next)-(unsigned char*)(finish_task_switch))*sizeof(instr_t), GFP_KERNEL); 288 | if(!v){ 289 | printk("Errore 1\n"); 290 | return 0; 291 | } 292 | memset(v, 0, ((unsigned char*)(finish_task_switch_next)-(unsigned char*)(finish_task_switch))*sizeof(instr_t)); 293 | 294 | 295 | b=(backup_t*) kmalloc(20*sizeof(backup_t), GFP_KERNEL); //this size is the maximum number of return this module can handle 296 | if(!b){ 297 | printk("Errore 2\n"); 298 | return 0; 299 | } 300 | memset(b, 0, 20*sizeof(backup_t)); 301 | 302 | //instr_t* v will contain all the instructions between finish_task_switch and finish_task_switch_next 303 | temp=(void*)finish_task_switch; // copy of finish_task_switch for ld 304 | 305 | while (temp> 8 & 0xff); 354 | bytes_to_redirect[pos++] = (unsigned char)(displacement >> 16 & 0xff); 355 | bytes_to_redirect[pos++] = (unsigned char)(displacement >> 24 & 0xff); 356 | 357 | print_bytes("assembled jump is", bytes_to_redirect, 5); 358 | 359 | backup_count++; 360 | 361 | //Patch schedule() 362 | //if (backup_count!=-1) 363 | memcpy(upper_bound, bytes_to_redirect, 5); 364 | } 365 | } 366 | 367 | print_bytes("schedule after patch: ", finish_task_switch, finish_task_switch_next-finish_task_switch); 368 | 369 | //here all bytes are backed-up 370 | 371 | int patch_size=schedule_hook_2-schedule_hook_patch_point; 372 | int patch_offset=schedule_hook_patch_point_2-schedule_hook_patch_point; 373 | printk(KERN_DEBUG "%s: schedule_hook is at address %p\n", KBUILD_MODNAME, schedule_hook); 374 | print_bytes("schedule_hook_patch_point: ", schedule_hook_patch_point, patch_size); 375 | 376 | //patch schedule_hook_patch_point 377 | 378 | for (j=0; j 30 | 31 | #define TSTRETCH_IOCTL_MAGIC 'T' 32 | 33 | #define UNLIKELY_FLAG 0xf0f0f0f0 34 | #define RESET_FLAG 0x00000000 35 | 36 | #define MAX_STRETCH 3000 //this is expressed in milliseconds 37 | 38 | #define DELAY 1000 39 | #define ENABLE if(1) 40 | //#define MAX_CPUs 32 41 | #define SIBLING_PGD 128 // max number of concurrent memory views (concurrent root-sim worker threads on a node) 42 | #define TS_THREADS (SIBLING_PGD) //max number of concurrent HTM threads with time stretch 43 | 44 | 45 | 46 | 47 | #define HTM_THREADS 16 // max number of concurrent threads rnning HTM transactions with timer stretch 48 | 49 | #define IOCTL_SETUP_PID _IOW(TSTRETCH_IOCTL_MAGIC, 2, unsigned long ) 50 | #define IOCTL_SHUTDOWN_PID _IOW(TSTRETCH_IOCTL_MAGIC, 3, unsigned long ) 51 | #define IOCTL_SHUTDOWN_ACK _IOW(TSTRETCH_IOCTL_MAGIC, 4, unsigned long ) 52 | #define IOCTL_SHUTDOWN_VIEWS _IOW(TSTRETCH_IOCTL_MAGIC, 5, unsigned long ) 53 | 54 | #endif /* __KERNEL_TIME_SLICE_STRETCH */ 55 | --------------------------------------------------------------------------------