wolfssl/linuxkm/Kbuild

220 lines
8.7 KiB
Makefile

# Linux kernel-native Makefile ("Kbuild") for libwolfssl.ko
#
# Copyright (C) 2006-2025 wolfSSL Inc.
#
# This file is part of wolfSSL.
#
# wolfSSL 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.
#
# wolfSSL 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1335, USA
.ONESHELL:
SHELL=bash
ifeq "$(KERNEL_ARCH)" "x86"
KERNEL_ARCH_X86 := yes
else ifeq "$(KERNEL_ARCH)" "x86_64"
KERNEL_ARCH_X86 := yes
else
KERNEL_ARCH_X86 := no
endif
ifeq "$(WOLFSSL_OBJ_FILES)" ""
$(error $$WOLFSSL_OBJ_FILES is unset.)
endif
ifeq "$(WOLFSSL_CFLAGS)" ""
$(error $$WOLFSSL_CFLAGS is unset.)
endif
WOLFSSL_CFLAGS += -ffreestanding -Wframe-larger-than=$(MAX_STACK_FRAME_SIZE) -isystem $(shell $(CC) -print-file-name=include)
ifeq "$(KERNEL_ARCH)" "aarch64"
WOLFSSL_CFLAGS += -mno-outline-atomics
else ifeq "$(KERNEL_ARCH)" "arm64"
WOLFSSL_CFLAGS += -mno-outline-atomics
endif
obj-m := libwolfssl.o
WOLFSSL_OBJ_TARGETS := $(patsubst %, $(obj)/%, $(WOLFSSL_OBJ_FILES))
ifeq "$(ENABLED_LINUXKM_PIE)" "yes"
WOLFCRYPT_PIE_FILES := $(patsubst %, $(obj)/%, $(WOLFCRYPT_PIE_FILES))
endif
$(obj)/linuxkm/module_exports.o: $(WOLFSSL_OBJ_TARGETS)
ifndef KERNEL_THREAD_STACK_SIZE
ifdef CROSS_COMPILE
KERNEL_THREAD_STACK_SIZE=16384
endif
endif
# this mechanism only works in kernel 5.x+ (fallback to hardcoded value)
ifndef KERNEL_THREAD_STACK_SIZE
hostprogs := linuxkm/get_thread_size
always-y := $(hostprogs)
endif
HOST_EXTRACFLAGS += $(NOSTDINC_FLAGS) $(LINUXINCLUDE) $(KBUILD_CFLAGS) -static -fno-omit-frame-pointer
# "-mindirect-branch=keep -mfunction-return=keep" to avoid "undefined reference
# to `__x86_return_thunk'" on CONFIG_RETHUNK kernels (5.19.0-rc7)
ifeq "$(KERNEL_ARCH_X86)" "yes"
HOST_EXTRACFLAGS += -mindirect-branch=keep -mfunction-return=keep
endif
# this rule is needed to get build to succeed in 4.x (get_thread_size still doesn't get built)
$(obj)/linuxkm/get_thread_size: $(src)/linuxkm/get_thread_size.c
ifndef KERNEL_THREAD_STACK_SIZE
$(WOLFSSL_OBJ_TARGETS): | $(obj)/linuxkm/get_thread_size
KERNEL_THREAD_STACK_SIZE=$(shell test -x $(obj)/linuxkm/get_thread_size && $(obj)/linuxkm/get_thread_size || echo 16384)
endif
MAX_STACK_FRAME_SIZE=$(shell echo $$(( $(KERNEL_THREAD_STACK_SIZE) / 4)))
libwolfssl-y := $(WOLFSSL_OBJ_FILES) linuxkm/module_hooks.o linuxkm/module_exports.o
WOLFSSL_CFLAGS_NO_VECTOR_INSNS := $(CFLAGS_SIMD_DISABLE) $(CFLAGS_FPU_DISABLE)
ifeq "$(ENABLED_ASM)" "yes"
WOLFSSL_CFLAGS_YES_VECTOR_INSNS := $(CFLAGS_SIMD_ENABLE) $(CFLAGS_FPU_DISABLE) $(CFLAGS_AUTO_VECTORIZE_DISABLE)
else
WOLFSSL_CFLAGS_YES_VECTOR_INSNS := $(WOLFSSL_CFLAGS_NO_VECTOR_INSNS)
endif
ccflags-y := $(WOLFSSL_CFLAGS) $(WOLFSSL_CFLAGS_NO_VECTOR_INSNS)
$(obj)/libwolfssl.mod.o: ccflags-y :=
$(obj)/wolfcrypt/test/test.o: ccflags-y += -DNO_MAIN_DRIVER -DWOLFSSL_NO_OPTIONS_H
$(obj)/wolfcrypt/src/aes.o: ccflags-y = $(WOLFSSL_CFLAGS) $(WOLFSSL_CFLAGS_YES_VECTOR_INSNS)
ifeq "$(ENABLED_LINUXKM_PIE)" "yes"
PIE_FLAGS := -fPIE -fno-stack-protector -fno-toplevel-reorder
PIE_SUPPORT_FLAGS := -DUSE_WOLFSSL_LINUXKM_PIE_REDIRECT_TABLE
ifeq "$(KERNEL_ARCH_X86)" "yes"
PIE_FLAGS += -mcmodel=small -mindirect-branch=keep -mfunction-return=keep
endif
ifeq "$(KERNEL_ARCH)" "mips"
PIE_FLAGS += -mabicalls
endif
$(WOLFCRYPT_PIE_FILES): ccflags-y += $(PIE_SUPPORT_FLAGS) $(PIE_FLAGS)
$(WOLFCRYPT_PIE_FILES): ccflags-remove-y += -pg
# disabling retpoline generation leads to profuse warnings without this:
$(WOLFCRYPT_PIE_FILES): OBJECT_FILES_NON_STANDARD := y
$(obj)/linuxkm/module_hooks.o: ccflags-y += $(PIE_SUPPORT_FLAGS)
endif
$(obj)/wolfcrypt/benchmark/benchmark.o: ccflags-y = $(WOLFSSL_CFLAGS) $(CFLAGS_FPU_ENABLE) $(CFLAGS_SIMD_ENABLE) $(PIE_SUPPORT_FLAGS) -DNO_MAIN_FUNCTION -DWOLFSSL_NO_OPTIONS_H
$(obj)/wolfcrypt/benchmark/benchmark.o: asflags-y = $(WOLFSSL_ASFLAGS) $(ASFLAGS_FPU_ENABLE_SIMD_DISABLE)
asflags-y := $(WOLFSSL_ASFLAGS) $(ASFLAGS_FPUSIMD_DISABLE)
# vectorized implementations that are kernel-safe are listed here.
# these are known kernel-compatible, but need the vector instructions enabled in the assembler,
# and most of them still irritate objtool.
$(obj)/wolfcrypt/src/aes_asm.o: asflags-y = $(WOLFSSL_ASFLAGS) $(ASFLAGS_FPU_DISABLE_SIMD_ENABLE)
$(obj)/wolfcrypt/src/aes_asm.o: OBJECT_FILES_NON_STANDARD := y
$(obj)/wolfcrypt/src/aes_gcm_asm.o: asflags-y = $(WOLFSSL_ASFLAGS) $(ASFLAGS_FPU_DISABLE_SIMD_ENABLE)
$(obj)/wolfcrypt/src/aes_gcm_asm.o: OBJECT_FILES_NON_STANDARD := y
$(obj)/wolfcrypt/src/aes_xts_asm.o: asflags-y = $(WOLFSSL_ASFLAGS) $(ASFLAGS_FPU_DISABLE_SIMD_ENABLE)
$(obj)/wolfcrypt/src/aes_xts_asm.o: OBJECT_FILES_NON_STANDARD := y
$(obj)/wolfcrypt/src/sp_x86_64_asm.o: asflags-y = $(WOLFSSL_ASFLAGS) $(ASFLAGS_FPU_DISABLE_SIMD_ENABLE)
$(obj)/wolfcrypt/src/sp_x86_64_asm.o: OBJECT_FILES_NON_STANDARD := y
$(obj)/wolfcrypt/src/sha256_asm.o: asflags-y = $(WOLFSSL_ASFLAGS) $(ASFLAGS_FPU_DISABLE_SIMD_ENABLE)
$(obj)/wolfcrypt/src/sha256_asm.o: OBJECT_FILES_NON_STANDARD := y
$(obj)/wolfcrypt/src/sha512_asm.o: asflags-y = $(WOLFSSL_ASFLAGS) $(ASFLAGS_FPU_DISABLE_SIMD_ENABLE)
$(obj)/wolfcrypt/src/sha512_asm.o: OBJECT_FILES_NON_STANDARD := y
$(obj)/wolfcrypt/src/sha3_asm.o: asflags-y = $(WOLFSSL_ASFLAGS) $(ASFLAGS_FPU_DISABLE_SIMD_ENABLE)
$(obj)/wolfcrypt/src/sha3_asm.o: OBJECT_FILES_NON_STANDARD := y
$(obj)/wolfcrypt/src/chacha_asm.o: asflags-y = $(WOLFSSL_ASFLAGS) $(ASFLAGS_FPU_DISABLE_SIMD_ENABLE)
$(obj)/wolfcrypt/src/chacha_asm.o: OBJECT_FILES_NON_STANDARD := y
$(obj)/wolfcrypt/src/poly1305_asm.o: asflags-y = $(WOLFSSL_ASFLAGS) $(ASFLAGS_FPU_DISABLE_SIMD_ENABLE)
$(obj)/wolfcrypt/src/poly1305_asm.o: OBJECT_FILES_NON_STANDARD := y
$(obj)/wolfcrypt/src/wc_mlkem_asm.o: asflags-y = $(WOLFSSL_ASFLAGS) $(ASFLAGS_FPU_DISABLE_SIMD_ENABLE)
$(obj)/wolfcrypt/src/wc_mlkem_asm.o: OBJECT_FILES_NON_STANDARD := y
ifndef READELF
READELF := readelf
endif
ifeq "$(ENABLED_LINUXKM_PIE)" "yes"
rename-pie-text-and-data-sections: $(WOLFSSL_OBJ_TARGETS)
ifndef NM
NM := nm
endif
ifndef OBJCOPY
OBJCOPY := objcopy
endif
.PHONY: rename-pie-text-and-data-sections
rename-pie-text-and-data-sections:
ifneq "$(quiet)" "silent_"
@echo -n ' Checking wolfCrypt for unresolved symbols and forbidden relocations... '
endif
@cd "$(obj)" || exit $$?
$(LD) -relocatable -o wolfcrypt_test_link.o $(WOLFCRYPT_PIE_FILES) || exit $$?
undefined=$$($(NM) --undefined-only wolfcrypt_test_link.o) || exit $$?
GOT_relocs=$$($(READELF) --relocs --wide wolfcrypt_test_link.o | egrep '^[^ ]+ +[^ ]+ +[^ ]*GOT[^ ]* ') || [ $$? = 1 ] || exit 2
rm wolfcrypt_test_link.o
if [ -n "$$undefined" ]; then
echo "wolfCrypt container has unresolved symbols:" 1>&2
echo "$$undefined" 1>&2
exit 1
fi
if [ -n "$$GOT_relocs" ]; then
echo "wolfCrypt container has GOT relocations (non-local function address used as operand?):" 1>&2
echo "$$GOT_relocs" 1>&2
exit 1
fi
ifneq "$(quiet)" "silent_"
echo 'OK.'
endif
cd "$(obj)" || exit $$?
for file in $(WOLFCRYPT_PIE_FILES); do
$(OBJCOPY) --rename-section .text=.text.wolfcrypt --rename-section .data=.data.wolfcrypt --rename-section .rodata=.rodata.wolfcrypt "$$file" || exit $$?
done
ifneq "$(quiet)" "silent_"
echo ' wolfCrypt .{text,data,rodata} sections containerized to .{text,data,rodata}.wolfcrypt'
endif
$(obj)/linuxkm/module_exports.c: rename-pie-text-and-data-sections
endif
# auto-generate the exported symbol list, leveraging the WOLFSSL_API visibility tags.
# exclude symbols that don't match wc_* or wolf*.
$(obj)/linuxkm/module_exports.c: $(src)/module_exports.c.template $(WOLFSSL_OBJ_TARGETS)
@cp $< $@ || exit $$?
if [[ "$${VERSION}" -gt 6 || ("$${VERSION}" -eq 6 && "$${PATCHLEVEL}" -ge 13) ]]; then
# use ASCII octal escape to avoid syntax disruption in the awk script.
ns='\042WOLFSSL\042'
else
ns='WOLFSSL'
fi
$(READELF) --symbols --wide $(WOLFSSL_OBJ_TARGETS) |
$(AWK) '/^ *[0-9]+: / {
if ($$8 !~ /^(wc_|wolf|WOLF|TLSX_)/){next;}
if (($$4 == "FUNC") && ($$5 == "GLOBAL") && ($$6 == "DEFAULT")) {
print "EXPORT_SYMBOL_NS_GPL(" $$8 ", '"$$ns"');";
}
}' >> $@ || exit $$?
echo -e "#ifndef NO_CRYPT_TEST\nEXPORT_SYMBOL_NS_GPL(wolfcrypt_test, $${ns});\n#endif" >> $@
clean-files := linuxkm src wolfcrypt