Signed-off-by: Bill Roberts <bill.robe...@arm.com>
---
acinclude.m4 | 33 +++++++++++
configure.ac | 20 ++++++-
mpn/Makeasm.am | 3 +-
mpn/arm64/arm64-defs.m4 | 100 +++++++++++++++++++++++++++++++++
mpn/arm64/divrem_1.asm | 8 ++-
tests/mpn/Makefile.am | 43 +++++++++-----
tests/mpn/log-compiler.sh | 21 +++++++
tests/mpn/t-arm64_bti.c | 87 ++++++++++++++++++++++++++++
tests/mpn/t-arm64_elf_check.sh | 96 +++++++++++++++++++++++++++++++
9 files changed, 394 insertions(+), 17 deletions(-)
create mode 100755 tests/mpn/log-compiler.sh
create mode 100644 tests/mpn/t-arm64_bti.c
create mode 100755 tests/mpn/t-arm64_elf_check.sh
diff --git a/acinclude.m4 b/acinclude.m4
index 4fca12de2..8f683516a 100644
--- a/acinclude.m4
+++ b/acinclude.m4
@@ -3992,3 +3992,36 @@ case $gmp_cv_check_libm_for_build in
*) LIBM_FOR_BUILD=$gmp_cv_check_libm_for_build ;;
esac
])
+
+# Define GMP_GET_MACRO_VALUE to capture the value of a C preprocessor symbol
via compilation.
+# This is useful when something like AC_EGREP_CPP doesn't have the correct
environment.
+# Arg 1 - The name of the macro to check in the compiled program.
+# Arg 2 - The variable name to define the value of the macro to.
+# Arg 3 - The default value if not defined.
+#
+# Example: GMP_GET_MACRO_VALUE([FOO], [BAR], [0])
+# This will check for macro FOO and define in a new variable BAR the value
+# of FOO as derived from invoking the C pre-processor or the default value
+# as specified by the caller.
+#
+AC_DEFUN([GMP_GET_MACRO_VALUE], [
+ AC_MSG_CHECKING([value of $1])
+
+ $2=$(printf "#ifdef $1\n$1_VALUE=$1\n#else\n$1_VALUE=$3\n#endif\n" | ${CC} ${CFLAGS}
-E - | grep "$1_VALUE" | cut -d'=' -f2-)
+ AC_MSG_RESULT([$$2])
+])
+
+# Define GMP_CHECK_PROG to find a host program using AC_CHECK_PROG and fail if
not found.
+#
+# Arg 1 - The name of the variable to define if found.
+# Arg 2 - The program to check for, and the value of the variable named in
argument 1.
+#
+# Example: GMP_CHECK_PROG([GREP], [grep])
+# This will check for program grep and define GREP equal to "grep"
+#
+AC_DEFUN([GMP_CHECK_PROG], [
+ AC_CHECK_PROG([$1], [$2], [$2])
+ if test "$$1" != "$2"; then
+ AC_MSG_FAILURE([Could not find $2! Ensure it's on PATH and/or installed.])
+ fi
+])
diff --git a/configure.ac b/configure.ac
index edee25fae..5c7d01634 100644
--- a/configure.ac
+++ b/configure.ac
@@ -82,6 +82,8 @@ AM_INIT_AUTOMAKE([1.8 gnu no-dependencies subdir-objects])
AC_CONFIG_HEADERS(config.h:config.in)
AM_MAINTAINER_MODE
+GMP_CHECK_PROG([GREP], [grep])
+GMP_CHECK_PROG([CUT], [cut])
AC_ARG_ENABLE(assert,
AS_HELP_STRING([--enable-assert],[enable ASSERT checking [default=no]]),
@@ -3767,7 +3769,17 @@ if test "$gmp_asm_syntax_testing" != no; then
*-*-darwin*)
GMP_INCLUDE_MPN(arm64/darwin.m4) ;;
*)
- GMP_INCLUDE_MPN(arm64/arm64-defs.m4) ;;
+ GMP_INCLUDE_MPN(arm64/arm64-defs.m4)
+ GMP_GET_MACRO_VALUE([__ARM_FEATURE_BTI_DEFAULT],
[ARM64_FEATURE_BTI_DEFAULT], [0])
+
GMP_DEFINE_RAW(["define(<ARM64_FEATURE_BTI_DEFAULT>,<$ARM64_FEATURE_BTI_DEFAULT>)"])
+ AC_SUBST([ARM64_FEATURE_BTI_DEFAULT])
+
+ GMP_GET_MACRO_VALUE([__ARM_FEATURE_PAC_DEFAULT],
[ARM64_FEATURE_PAC_DEFAULT], [0])
+
GMP_DEFINE_RAW(["define(<ARM64_FEATURE_PAC_DEFAULT>,<$ARM64_FEATURE_PAC_DEFAULT>)"])
+ AC_SUBST([ARM64_FEATURE_PAC_DEFAULT])
+
+ GMP_GET_MACRO_VALUE([__ELF__], [ARM64_ELF], [0])
+ GMP_DEFINE_RAW(["define(<ARM64_ELF>,<$ARM64_ELF>)"])
esac
;;
esac
@@ -4058,6 +4070,12 @@ fi
AC_PROG_YACC
AM_PROG_LEX
+AC_CHECK_TOOL([HAVE_BASH], [bash], [no])
+AM_CONDITIONAL([HAVE_BASH], [test "$HAVE_BASH" != "no"])
+
+AC_CHECK_TOOL([HAVE_READELF], [readelf], [no])
+AM_CONDITIONAL([HAVE_READELF], [test "$HAVE_READELF" != "no"])
+
# Create config.m4.
GMP_FINISH
diff --git a/mpn/Makeasm.am b/mpn/Makeasm.am
index 5d7306c22..527bf41cf 100644
--- a/mpn/Makeasm.am
+++ b/mpn/Makeasm.am
@@ -115,4 +115,5 @@ RM_TMP = rm -f
$(CCAS) $(COMPILE_FLAGS) tmp-$*.s -o $@
$(RM_TMP) tmp-$*.s
.asm.lo:
- $(LIBTOOL) --mode=compile --tag=CC $(top_srcdir)/mpn/m4-ccas --m4="$(M4)"
$(CCAS) $(COMPILE_FLAGS) `test -f '$<' || echo '$(srcdir)/'`$<
+ $(LIBTOOL) --mode=compile --tag=CC $(top_srcdir)/mpn/m4-ccas
--m4="$(M4)" \
+ $(CCAS) $(COMPILE_FLAGS) `test -f '$<' || echo '$(srcdir)/'`$<
diff --git a/mpn/arm64/arm64-defs.m4 b/mpn/arm64/arm64-defs.m4
index 46149f7bf..c717e5ebd 100644
--- a/mpn/arm64/arm64-defs.m4
+++ b/mpn/arm64/arm64-defs.m4
@@ -36,6 +36,101 @@ dnl don't want to disable macro expansions in or after
them.
changecom
+dnl use the hint instructions so they NOP on older machines.
+dnl Add comments so the assembly is notated with the instruction
+
+
+define(`PACIASP', `hint #25 /* paciasp */')
+define(`AUTIASP', `hint #29 /* autiasp */')
+define(`PACIBSP', `hint #27 /* pacibsp */')
+define(`AUTIBSP', `hint #31 /* autibsp */')
+
+dnl if BTI is enabled we want the SIGN_LR to be a valid
+dnl landing pad, we don't need VERIFY_LR and we need to
+dnl indicate the valid BTI support for gnu notes.
+
+
+ifelse(ARM64_FEATURE_BTI_DEFAULT, `1',
+ `define(`BTI_C', `hint #34 /* bti c */')
+ define(`SIGN_LR', `BTI_C')
+ define(`GNU_PROPERTY_AARCH64_BTI', `1')
+ define(`PAC_OR_BTI')', `
+ define(`BTI_C', `')
+ define(`GNU_PROPERTY_AARCH64_BTI', `0')'
+')
+
+dnl define instructions for PAC, which can use the A
+dnl or the B key. PAC instructions are also valid BTI
+dnl landing pads, so we re-define SIGN_LR if BTI is
+dnl enabled.
+
+
+ifelse(ARM64_FEATURE_PAC_DEFAULT, `1',
+ `define(`SIGN_LR', `PACIASP')
+ define(`VERIFY_LR', `AUTIASP')
+ define(`GNU_PROPERTY_AARCH64_POINTER_AUTH', `2')
+ define(`PAC_OR_BTI')',
+ ARM64_FEATURE_PAC_DEFAULT, `2',
+ `define(`SIGN_LR', `PACIBSP')
+ define(`VERIFY_LR', `AUTIBSP')
+ define(`GNU_PROPERTY_AARCH64_POINTER_AUTH', `2')
+ define(`PAC_OR_BTI')',
+ `ifdef(`SIGN_LR', , `define(`SIGN_LR', `')')
+ define(`VERIFY_LR', `')
+ define(`GNU_PROPERTY_AARCH64_POINTER_AUTH', `0')'
+')
+
+dnl NOTE OVERRIDES asm-defs.m4 definition for arch specific functionality
+dnl
+dnl Usage: PROLOGUE_cpu(GSYM_PREFIX`'foo[,param])
+dnl EPILOGUE_cpu(GSYM_PREFIX`'foo)
+dnl
+dnl These macros hold the CPU-specific parts of PROLOGUE and is called
+dnl with the function name, with GSYM_PREFIX already prepended.
+dnl
+dnl By default, it marks entry points with a bti c instruction unless
+dnl the second argument is true and it marks it using SIGN_LR which expands
+dnl to the proper paci instruction OR bti c instruction depending on
+dnl compilation flags. In the case of an instruction that uses paci, this
+dnl provides a one instruction advantage over having a bti c followed by
+dnl a paci instruction.
+
+define(`PROLOGUE_cpu',
+m4_assert_numargs_range(1,2)
+` TEXT
+ ALIGN(8)
+ GLOBL `$1' GLOBL_ATTR
+ TYPE(`$1',`function')
+`$1'LABEL_SUFFIX
+ ifelse(`$2',`true',
+ `SIGN_LR',
+ `BTI_C')
+')
+
+dnl ADD_GNU_NOTES_IF_NEEDED
+dnl
+dnl Conditionally add into ELF assembly files the GNU notes indicating if
+dnl BTI or PAC is support. BTI is required by the linkers and loaders, however
+dnl PAC is a nice to have for auditing. Use readelf -n to display.
+
+
+define(`ADD_GNU_NOTES_IF_NEEDED', `
+ ifdef(`ARM64_ELF', `
+ ifdef(`PAC_OR_BTI', `
+ .pushsection .note.gnu.property, "a";
+ .balign 8;
+ .long 4;
+ .long 0x10;
+ .long 0x5;
+ .asciz "GNU";
+ .long 0xc0000000; /* GNU_PROPERTY_AARCH64_FEATURE_1_AND */
+ .long 4;
+ .long eval(indir(`GNU_PROPERTY_AARCH64_POINTER_AUTH') +
indir(`GNU_PROPERTY_AARCH64_BTI'));
+ .long 0;
+ .popsection;
+ ')
+ ')
+')
dnl LEA_HI(reg,gmp_symbol), LEA_LO(reg,gmp_symbol)
dnl
@@ -50,4 +145,9 @@ define(`LEA_HI', `adrp $1, $2')dnl
define(`LEA_LO', `add $1, $1, :lo12:$2')dnl
')dnl
+dnl divert output to the following m4 file to shove the GNU Notes section into subsequent
+dnl files implicitly.
+divert(1)
+ADD_GNU_NOTES_IF_NEEDED
+
divert`'dnl
diff --git a/mpn/arm64/divrem_1.asm b/mpn/arm64/divrem_1.asm
index 9d5bb5959..2c5265780 100644
--- a/mpn/arm64/divrem_1.asm
+++ b/mpn/arm64/divrem_1.asm
@@ -65,7 +65,7 @@ dnl mp_limb_t d_unnorm, mp_limb_t dinv,
int cnt)
ASM_START()
-PROLOGUE(mpn_preinv_divrem_1)
+PROLOGUE(mpn_preinv_divrem_1, true)
cbz n_arg, L(fz)
stp x29, x30, [sp, #-80]!
mov x29, sp
@@ -85,7 +85,7 @@ PROLOGUE(mpn_preinv_divrem_1)
b L(uentry)
EPILOGUE()
-PROLOGUE(mpn_divrem_1)
+PROLOGUE(mpn_divrem_1, true)
cbz n_arg, L(fz)
stp x29, x30, [sp, #-80]!
mov x29, sp
@@ -154,6 +154,7 @@ L(uend):add x2, x11, #1
ldp x21, x22, [sp, #32]
ldp x23, x24, [sp, #48]
ldp x29, x30, [sp], #80
+ VERIFY_LR
ret
L(ufx): add x2, x2, #1
@@ -194,6 +195,7 @@ L(nend):cbnz fn, L(frac)
ldp x21, x22, [sp, #32]
ldp x23, x24, [sp, #48]
ldp x29, x30, [sp], #80
+ VERIFY_LR
ret
L(nfx): add x2, x2, #1
@@ -219,6 +221,7 @@ L(ftop):add x2, x11, #1
ldp x21, x22, [sp, #32]
ldp x23, x24, [sp, #48]
ldp x29, x30, [sp], #80
+ VERIFY_LR
ret
C Block zero. We need this for the degenerated case of n = 0, fn != 0.
@@ -227,5 +230,6 @@ L(ztop):str xzr, [qp_arg], #8
sub fn_arg, fn_arg, #1
cbnz fn_arg, L(ztop)
L(zend):mov x0, #0
+ VERIFY_LR
ret
EPILOGUE()
diff --git a/tests/mpn/Makefile.am b/tests/mpn/Makefile.am
index 0e979a3ad..16d4d2dc6 100644
--- a/tests/mpn/Makefile.am
+++ b/tests/mpn/Makefile.am
@@ -22,19 +22,36 @@ AM_CPPFLAGS = -I$(top_srcdir) -I$(top_srcdir)/tests
AM_LDFLAGS = -no-install
LDADD = $(top_builddir)/tests/libtests.la $(top_builddir)/libgmp.la
-check_PROGRAMS = t-asmtype t-aors_1 t-divrem_1 t-mod_1 t-fat t-get_d \
- t-instrument t-iord_u t-mp_bases t-perfsqr t-scan logic \
- t-toom22 t-toom32 t-toom33 t-toom42 t-toom43 t-toom44
\
- t-toom52 t-toom53 t-toom54 t-toom62 t-toom63 t-toom6h t-toom8h \
- t-toom2-sqr t-toom3-sqr t-toom4-sqr t-toom6-sqr t-toom8-sqr \
- t-div t-mul t-mullo t-sqrlo t-mulmod_bnm1 t-sqrmod_bnm1 t-mulmid \
- t-mulmod_bknp1 t-sqrmod_bknp1
\
- t-addaddmul t-hgcd t-hgcd_appr t-matrix22 t-invert t-bdiv t-fib2m \
- t-broot t-brootinv t-minvert t-sizeinbase t-gcd_11 t-gcd_22 t-gcdext_1
-
-EXTRA_DIST = toom-shared.h toom-sqr-shared.h
-
-TESTS = $(check_PROGRAMS)
+TEST_EXTENSIONS = .sh
+AM_SH_LOG_FLAGS = --enable-pac=@ARM64_FEATURE_PAC_DEFAULT@ \
+ --enable-bti=@ARM64_FEATURE_BTI_DEFAULT@ \
+ $(top_builddir)/.libs/libgmp.so
+SH_LOG_COMPILER = $(srcdir)/log-compiler.sh
+
+check_PROGRAMS = t-asmtype t-aors_1 t-divrem_1 t-mod_1 t-fat t-get_d \
+ t-instrument t-iord_u t-mp_bases t-perfsqr t-scan logic \
+ t-toom22 t-toom32 t-toom33 t-toom42 t-toom43 t-toom44
\
+ t-toom52 t-toom53 t-toom54 t-toom62 t-toom63 t-toom6h t-toom8h \
+ t-toom2-sqr t-toom3-sqr t-toom4-sqr t-toom6-sqr t-toom8-sqr \
+ t-div t-mul t-mullo t-sqrlo t-mulmod_bnm1 t-sqrmod_bnm1 t-mulmid \
+ t-mulmod_bknp1 t-sqrmod_bknp1
\
+ t-addaddmul t-hgcd t-hgcd_appr t-matrix22 t-invert t-bdiv t-fib2m \
+ t-broot t-brootinv t-minvert t-sizeinbase t-gcd_11 t-gcd_22 t-gcdext_1 \
+ t-arm64_bti
+
+test_scripts =
+if HAVE_BASH
+if HAVE_READELF
+ test_scripts += t-arm64_elf_check.sh
+endif
+endif
+check_SCRIPTS = $(test_scripts)
+
+EXTRA_DIST = toom-shared.h toom-sqr-shared.h t-arm64_elf_check.sh
+
+TESTS = $(check_PROGRAMS) $(check_SCRIPTS)
+
+XFAIL_TESTS = t-arm64_bti
$(top_builddir)/tests/libtests.la:
cd $(top_builddir)/tests; $(MAKE) $(AM_MAKEFLAGS) libtests.la
diff --git a/tests/mpn/log-compiler.sh b/tests/mpn/log-compiler.sh
new file mode 100755
index 000000000..092b21b33
--- /dev/null
+++ b/tests/mpn/log-compiler.sh
@@ -0,0 +1,21 @@
+#!/usr/bin/env bash
+
+echo "Log Compiler: $@"
+
+# Flip <options> command to command <options> by swaping the
+# first and last elements of the argv array
+# Convert "$@" to an array for easy manipulation
+args=("$@")
+
+# Get the indices for the first and last elements
+first=0
+last=$((${#args[@]} - 1))
+
+# Swap the first and last elements
+temp="${args[$first]}"
+args[$first]="${args[$last]}"
+args[$last]="$temp"
+
+# Run the script
+./${args[@]}
+exit $?
diff --git a/tests/mpn/t-arm64_bti.c b/tests/mpn/t-arm64_bti.c
new file mode 100644
index 000000000..ca8ab22bb
--- /dev/null
+++ b/tests/mpn/t-arm64_bti.c
@@ -0,0 +1,87 @@
+/*
+Copyright 2024 Free Software Foundation, Inc.
+
+This file is part of the GNU MP Library test suite.
+
+The GNU MP Library test suite 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 3 of the License,
+or (at your option) any later version.
+
+The GNU MP Library test suite 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
+the GNU MP Library test suite. If not, see https://www.gnu.org/licenses/. */
+
+/*
+ * Test if if BTI is working within the GMP assembly stubs for AArch64 aka
arm64
+ * within GMP. This test gets a function pointer to mpn_lshift avoiding the PLT
+ * using dlsym and calls the function and checks for a valid return. It then
+ * advances the function pointer by 2, which points us to the next instruction,
+ * and calls. The following scenarios are possible:
+ * | Binary BTI Enabled | Hardware BTI Enabled | Executable Outcome | Test
Outcome |
+ * | 0 | 0 | Works returning 77 | SKIP
|
+ * | 0 | 1 | Works returning 77 | SKIP
|
+ * | 1 | 0 | Works returning 77 | SKIP
|
+ * | 1 | 1 | BTI Exception | PASS
|
+ * Note: 77 is the magic value for autotools to indicate to skip a test.
+ * Note: You MUST run this test when enabled on a BTI enabled hardware setup.
+ * Note: That for non-aarch64 platforms, this also just skips.
+ */
+
+#define SKIP 77
+
+/* AArch64 BTI Binary enabled code ONLY */
+#ifdef __ARM_FEATURE_BTI_DEFAULT
+
+#include <stdint.h>
+#include <stdlib.h>
+#include <stdio.h>
+
+#include <dlfcn.h>
+#include <sys/auxv.h>
+#include <asm/hwcap.h>
+
+#include "gmp-impl.h"
+#include "tests.h"
+
+typedef mp_limb_t (*fn_mpn_lshift)(mp_ptr, mp_srcptr, mp_size_t, unsigned int);
+
+int
+main (int argc, char **argv)
+{
+ unsigned long hwcap2 = getauxval(AT_HWCAP2);
+ if (!(hwcap2 & HWCAP2_BTI)) {
+ fprintf(stderr, "Hardware does not support BTI\n");
+ return SKIP;
+ }
+
+ mp_limb_t xp = 0x1001, wp;
+
+ fn_mpn_lshift fn = dlsym(RTLD_DEFAULT, "__gmpn_lshift");
+ if (!fn) {
+ fprintf(stderr, "Could not find the symbol __gmpn_lshift\n");
+ /* This test should not pass, so zero will cause the test harness to
fail */
+ return 0;
+ }
+
+ /* should work as this will land on a BTI landing pad as expected */
+ fn (&wp, &xp, (mp_size_t) 1, 1);
+ ASSERT_ALWAYS (wp == 0x2002);
+
+ /* this should fail as it's off 1 instruction */
+ fn = (fn_mpn_lshift)((uintptr_t)fn + 4);
+ fn(&wp, &xp, (mp_size_t) 1, 1);
+ fprintf(stderr, "This should cause an exception, does your system support
BTI?\n");
+ return 0;
+}
+#else
+/* No binary support for BTI or another arch, just skips */
+int
+main (int argc, char **argv) {
+ return SKIP;
+}
+#endif
diff --git a/tests/mpn/t-arm64_elf_check.sh b/tests/mpn/t-arm64_elf_check.sh
new file mode 100755
index 000000000..12d238883
--- /dev/null
+++ b/tests/mpn/t-arm64_elf_check.sh
@@ -0,0 +1,96 @@
+#!/usr/bin/env bash
+
+set -e -o pipefail
+
+check_val() {
+
+ local grep_flags="-qi"
+ local not_msg=""
+ # invert the grep match if it SHOULDN'T be found in the flags.
+ # ie BTI 0 means BTI should not be in the notes.
+ if [ "${2}" -eq 0 ]; then
+ grep_flags+="v"
+ not_msg="Not "
+ fi
+
+ printf 'Checking for %s in "%s". Expecting "%sPresent", ' "${1}" "${ELF_BINARY}"
"${not_msg}"
+
+ set +e
+ readelf -n "${ELF_BINARY}" | grep $grep_flags -- "${1}"
+ local r="${?}"
+ set -e
+ # Possible states we care about, which grep will fail under:
+ # - State 1: Not expecting and Found
+ # - State 2: Expecting and not Found
+ if [[ "${r}" -ne 0 ]]; then
+ # Flip the not message
+ if [ -z "${not_msg}" ]; then
+ not_msg="Not "
+ else
+ not_msg=""
+ fi
+ fi
+
+ # print found or not found
+ printf 'got "%sPresent."\n' "${not_msg}"
+
+ # The grep result means we return the rc through the named variable
+ # this way consumers can just add all the values to determine if its
+ # a failure.
+ declare -g "${1}=${r}"
+}
+
+# Initialize variables
+BTI="0"
+PAC="0"
+ELF_BINARY=""
+
+# Loop through the arguments
+while [[ "${#}" -gt 0 ]]; do
+ case "${1}" in
+ --enable-bti=*)
+ BTI="${1#*=}"
+ shift
+ ;;
+ --enable-pac=*)
+ PAC="${1#*=}"
+ shift
+ ;;
+ --enable-bti | --enable-pac)
+ # If the argument is in the form --enable-bti value (without =)
+ printf 'Error: Option %s requires a value, like --enable-bti=value' "${1}"
+ exit 1
+ ;;
+ *)
+ # Handle the non-option argument
+ if [[ -z "${ELF_BINARY}" ]]; then
+ ELF_BINARY="${1}"
+ else
+ printf 'Error: More than one non-option argument provided: %s\n' "${1}"
+ exit 1
+ fi
+ shift
+ ;;
+ esac
+done
+
+if [ -z "${ELF_BINARY}" ]; then
+ printf "Must specify the ELF binary as the ONLY script argument\n"
+ exit 1
+fi
+
+# Skip if nothing is enabled, 77 is automake magic for SKIP this test.
+# For non-supporting architectures and ABIs both of these will be 0
+# and thus skip.
+if [[ "${BTI}" -eq 0 && "${PAC}" -eq 0 ]]; then
+ printf "PAC and BTI disabled...skipping\n"
+ exit 77
+fi
+
+check_val "BTI" "${BTI}"
+check_val "PAC" "${PAC}"
+
+# don't use expr as it returns non-zero when the addition result is non-zero
+# and causes the set -e script to fail.
+rc="$((BTI + PAC))"
+exit "${rc}"
