| dnl |
| dnl GCC_CET_FLAGS |
| dnl (SHELL-CODE_HANDLER) |
| dnl |
| AC_DEFUN([GCC_CET_FLAGS],[dnl |
| GCC_ENABLE(cet, no, ,[enable Intel CET in target libraries], |
| permit yes|no|auto) |
| AC_MSG_CHECKING([for CET support]) |
| |
| case "$host" in |
| i[[34567]]86-*-linux* | x86_64-*-linux*) |
| case "$enable_cet" in |
| auto) |
| # Check if target supports multi-byte NOPs |
| # and if assembler supports CET insn. |
| AC_COMPILE_IFELSE( |
| [AC_LANG_PROGRAM( |
| [], |
| [ |
| #if !defined(__SSE2__) |
| #error target does not support multi-byte NOPs |
| #else |
| asm ("setssbsy"); |
| #endif |
| ])], |
| [enable_cet=yes], |
| [enable_cet=no]) |
| ;; |
| yes) |
| # Check if assembler supports CET. |
| AC_COMPILE_IFELSE( |
| [AC_LANG_PROGRAM( |
| [], |
| [asm ("setssbsy");])], |
| [], |
| [AC_MSG_ERROR([assembler with CET support is required for --enable-cet])]) |
| ;; |
| esac |
| ;; |
| *) |
| enable_cet=no |
| ;; |
| esac |
| if test x$enable_cet = xyes; then |
| $1="-fcf-protection -mshstk" |
| AC_MSG_RESULT([yes]) |
| else |
| AC_MSG_RESULT([no]) |
| fi |
| ]) |
| |
| dnl |
| dnl GCC_CET_HOST_FLAGS |
| dnl (SHELL-CODE_HANDLER) |
| dnl |
| AC_DEFUN([GCC_CET_HOST_FLAGS],[dnl |
| GCC_ENABLE(cet, auto, ,[enable Intel CET in host libraries], |
| permit yes|no|auto) |
| AC_MSG_CHECKING([for CET support]) |
| |
| case "$host" in |
| i[[34567]]86-*-linux* | x86_64-*-linux*) |
| may_have_cet=yes |
| save_CFLAGS="$CFLAGS" |
| CFLAGS="$CFLAGS -fcf-protection" |
| case "$enable_cet" in |
| auto) |
| # Check if target supports multi-byte NOPs |
| # and if assembler supports CET insn. |
| AC_COMPILE_IFELSE( |
| [AC_LANG_PROGRAM( |
| [], |
| [ |
| #if !defined(__SSE2__) |
| #error target does not support multi-byte NOPs |
| #else |
| asm ("setssbsy"); |
| #endif |
| ])], |
| [enable_cet=yes], |
| [enable_cet=no]) |
| ;; |
| yes) |
| # Check if assembler supports CET. |
| AC_COMPILE_IFELSE( |
| [AC_LANG_PROGRAM( |
| [], |
| [asm ("setssbsy");])], |
| [], |
| [AC_MSG_ERROR([assembler with CET support is required for --enable-cet])]) |
| ;; |
| esac |
| CFLAGS="$save_CFLAGS" |
| ;; |
| *) |
| may_have_cet=no |
| enable_cet=no |
| ;; |
| esac |
| |
| save_CFLAGS="$CFLAGS" |
| CFLAGS="$CFLAGS -fcf-protection=none" |
| save_LDFLAGS="$LDFLAGS" |
| LDFLAGS="$LDFLAGS -Wl,-z,ibt,-z,shstk" |
| if test x$may_have_cet = xyes; then |
| # Check whether -fcf-protection=none -Wl,-z,ibt,-z,shstk work. |
| AC_TRY_LINK( |
| [],[return 0;], |
| [may_have_cet=yes], |
| [may_have_cet=no]) |
| fi |
| |
| if test x$may_have_cet = xyes; then |
| if test x$cross_compiling = xno; then |
| AC_TRY_RUN([ |
| static void |
| foo (void) |
| { |
| } |
| |
| static void |
| __attribute__ ((noinline, noclone)) |
| xxx (void (*f) (void)) |
| { |
| f (); |
| } |
| |
| static void |
| __attribute__ ((noinline, noclone)) |
| bar (void) |
| { |
| xxx (foo); |
| } |
| |
| int |
| main () |
| { |
| bar (); |
| return 0; |
| } |
| ], |
| [have_cet=no], |
| [have_cet=yes]) |
| if test x$enable_cet = xno -a x$have_cet = xyes; then |
| AC_MSG_ERROR([Intel CET must be enabled on Intel CET enabled host]) |
| fi |
| fi |
| else |
| # Enable CET in cross compiler if possible so that it will run on both |
| # CET and non-CET hosts. |
| have_cet=yes |
| fi |
| if test x$enable_cet = xyes; then |
| $1="-fcf-protection" |
| AC_MSG_RESULT([yes]) |
| else |
| AC_MSG_RESULT([no]) |
| fi |
| CFLAGS="$save_CFLAGS" |
| LDFLAGS="$save_LDFLAGS" |
| ]) |