buildenv.mk

#
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# Mitigation options

SGX_TRUSTED_INCLUDE_PATH ?= $(SGX_SDK)/include
SGX_TRUSTED_LIBRARY_PATH ?= $(SGX_SDK)/lib64

CC ?= gcc
CC_VERSION := $(shell $(CC) -dumpversion)
CC_NO_LESS_THAN_8 := $(shell expr $(CC_VERSION) \>\= "8")
BINUTILS_DIR ?= /usr/local/bin

MITIGATION_CFLAGS += -B$(BINUTILS_DIR)
MITIGATION_LDFLAGS += -B$(BINUTILS_DIR)

ifeq ($(MITIGATION-CVE-2020-0551), LOAD)
ifeq ($(CC_NO_LESS_THAN_8), 1)
    MITIGATION_CFLAGS += -fcf-protection=none
endif
    MITIGATION_CFLAGS += -mindirect-branch-register -mfunction-return=thunk-extern
    MITIGATION_ASFLAGS := -Wa,-mlfence-after-load=yes -Wa,-mlfence-before-indirect-branch=memory -Wa,-mlfence-before-ret=shl
    MITIGATION_ASFLAGS += -fno-plt
    SGX_TRUSTED_LIBRARY_PATH := $(SGX_TRUSTED_LIBRARY_PATH)/cve_2020_0551_load
else ifeq ($(MITIGATION-CVE-2020-0551), CF)
ifeq ($(CC_NO_LESS_THAN_8), 1)
    MITIGATION_CFLAGS += -fcf-protection=none
endif
    MITIGATION_CFLAGS += -mindirect-branch-register -mfunction-return=thunk-extern
    MITIGATION_ASFLAGS := -Wa,-mlfence-before-indirect-branch=all -Wa,-mlfence-before-ret=shl
    MITIGATION_ASFLAGS += -fno-plt
    SGX_TRUSTED_LIBRARY_PATH := $(SGX_TRUSTED_LIBRARY_PATH)/cve_2020_0551_cf
endif


MITIGATION_CFLAGS += $(MITIGATION_ASFLAGS)