diff options
| -rw-r--r-- | tools/testing/selftests/sgx/Makefile | 14 | ||||
| -rw-r--r-- | tools/testing/selftests/sgx/defines.h | 2 | ||||
| -rw-r--r-- | tools/testing/selftests/sgx/load.c | 9 | ||||
| -rw-r--r-- | tools/testing/selftests/sgx/sigstruct.c | 5 | ||||
| -rw-r--r-- | tools/testing/selftests/sgx/test_encl.c | 67 | ||||
| -rw-r--r-- | tools/testing/selftests/sgx/test_encl.lds | 10 | ||||
| -rw-r--r-- | tools/testing/selftests/sgx/test_encl_bootstrap.S | 28 |
7 files changed, 78 insertions, 57 deletions
diff --git a/tools/testing/selftests/sgx/Makefile b/tools/testing/selftests/sgx/Makefile index 50aab6b57da3..867f88ce2570 100644 --- a/tools/testing/selftests/sgx/Makefile +++ b/tools/testing/selftests/sgx/Makefile @@ -12,14 +12,16 @@ OBJCOPY := $(CROSS_COMPILE)objcopy endif INCLUDES := -I$(top_srcdir)/tools/include -HOST_CFLAGS := -Wall -Werror -g $(INCLUDES) -fPIC -z noexecstack -ENCL_CFLAGS := -Wall -Werror -static -nostdlib -nostartfiles -fPIC \ +HOST_CFLAGS := -Wall -Werror -g $(INCLUDES) -fPIC +HOST_LDFLAGS := -z noexecstack -lcrypto +ENCL_CFLAGS += -Wall -Werror -static-pie -nostdlib -ffreestanding -fPIE \ -fno-stack-protector -mrdrnd $(INCLUDES) +ENCL_LDFLAGS := -Wl,-T,test_encl.lds,--build-id=none +ifeq ($(CAN_BUILD_X86_64), 1) TEST_CUSTOM_PROGS := $(OUTPUT)/test_sgx TEST_FILES := $(OUTPUT)/test_encl.elf -ifeq ($(CAN_BUILD_X86_64), 1) all: $(TEST_CUSTOM_PROGS) $(OUTPUT)/test_encl.elf endif @@ -28,7 +30,7 @@ $(OUTPUT)/test_sgx: $(OUTPUT)/main.o \ $(OUTPUT)/sigstruct.o \ $(OUTPUT)/call.o \ $(OUTPUT)/sign_key.o - $(CC) $(HOST_CFLAGS) -o $@ $^ -lcrypto + $(CC) $(HOST_CFLAGS) -o $@ $^ $(HOST_LDFLAGS) $(OUTPUT)/main.o: main.c $(CC) $(HOST_CFLAGS) -c $< -o $@ @@ -45,8 +47,8 @@ $(OUTPUT)/call.o: call.S $(OUTPUT)/sign_key.o: sign_key.S $(CC) $(HOST_CFLAGS) -c $< -o $@ -$(OUTPUT)/test_encl.elf: test_encl.lds test_encl.c test_encl_bootstrap.S - $(CC) $(ENCL_CFLAGS) -T $^ -o $@ -Wl,--build-id=none +$(OUTPUT)/test_encl.elf: test_encl.c test_encl_bootstrap.S + $(CC) $(ENCL_CFLAGS) $^ -o $@ $(ENCL_LDFLAGS) EXTRA_CLEAN := \ $(OUTPUT)/test_encl.elf \ diff --git a/tools/testing/selftests/sgx/defines.h b/tools/testing/selftests/sgx/defines.h index d8587c971941..402f8787a71c 100644 --- a/tools/testing/selftests/sgx/defines.h +++ b/tools/testing/selftests/sgx/defines.h @@ -13,6 +13,8 @@ #define __aligned(x) __attribute__((__aligned__(x))) #define __packed __attribute__((packed)) +#define __used __attribute__((used)) +#define __section(x)__attribute__((__section__(x))) #include "../../../../arch/x86/include/asm/sgx.h" #include "../../../../arch/x86/include/asm/enclu.h" diff --git a/tools/testing/selftests/sgx/load.c b/tools/testing/selftests/sgx/load.c index 94bdeac1cf04..c9f658e44de6 100644 --- a/tools/testing/selftests/sgx/load.c +++ b/tools/testing/selftests/sgx/load.c @@ -136,11 +136,11 @@ static bool encl_ioc_add_pages(struct encl *encl, struct encl_segment *seg) */ uint64_t encl_get_entry(struct encl *encl, const char *symbol) { + Elf64_Sym *symtab = NULL; + char *sym_names = NULL; Elf64_Shdr *sections; - Elf64_Sym *symtab; Elf64_Ehdr *ehdr; - char *sym_names; - int num_sym; + int num_sym = 0; int i; ehdr = encl->bin; @@ -161,6 +161,9 @@ uint64_t encl_get_entry(struct encl *encl, const char *symbol) } } + if (!symtab || !sym_names) + return 0; + for (i = 0; i < num_sym; i++) { Elf64_Sym *sym = &symtab[i]; diff --git a/tools/testing/selftests/sgx/sigstruct.c b/tools/testing/selftests/sgx/sigstruct.c index a07896a46364..d73b29becf5b 100644 --- a/tools/testing/selftests/sgx/sigstruct.c +++ b/tools/testing/selftests/sgx/sigstruct.c @@ -318,9 +318,9 @@ bool encl_measure(struct encl *encl) struct sgx_sigstruct *sigstruct = &encl->sigstruct; struct sgx_sigstruct_payload payload; uint8_t digest[SHA256_DIGEST_LENGTH]; + EVP_MD_CTX *ctx = NULL; unsigned int siglen; RSA *key = NULL; - EVP_MD_CTX *ctx; int i; memset(sigstruct, 0, sizeof(*sigstruct)); @@ -384,7 +384,8 @@ bool encl_measure(struct encl *encl) return true; err: - EVP_MD_CTX_destroy(ctx); + if (ctx) + EVP_MD_CTX_destroy(ctx); RSA_free(key); return false; } diff --git a/tools/testing/selftests/sgx/test_encl.c b/tools/testing/selftests/sgx/test_encl.c index c0d6397295e3..2c4d709cce2d 100644 --- a/tools/testing/selftests/sgx/test_encl.c +++ b/tools/testing/selftests/sgx/test_encl.c @@ -5,11 +5,12 @@ #include "defines.h" /* - * Data buffer spanning two pages that will be placed first in .data - * segment. Even if not used internally the second page is needed by - * external test manipulating page permissions. + * Data buffer spanning two pages that will be placed first in the .data + * segment via the linker script. Even if not used internally the second page + * is needed by external test manipulating page permissions, so mark + * encl_buffer as "used" to make sure it is entirely preserved by the compiler. */ -static uint8_t encl_buffer[8192] = { 1 }; +static uint8_t __used __section(".data.encl_buffer") encl_buffer[8192] = { 1 }; enum sgx_enclu_function { EACCEPT = 0x5, @@ -24,10 +25,11 @@ static void do_encl_emodpe(void *_op) secinfo.flags = op->flags; asm volatile(".byte 0x0f, 0x01, 0xd7" - : + : /* no outputs */ : "a" (EMODPE), "b" (&secinfo), - "c" (op->epc_addr)); + "c" (op->epc_addr) + : "memory" /* read from secinfo pointer */); } static void do_encl_eaccept(void *_op) @@ -42,7 +44,8 @@ static void do_encl_eaccept(void *_op) : "=a" (rax) : "a" (EACCEPT), "b" (&secinfo), - "c" (op->epc_addr)); + "c" (op->epc_addr) + : "memory" /* read from secinfo pointer */); op->ret = rax; } @@ -119,21 +122,41 @@ static void do_encl_op_nop(void *_op) } +/* + * Symbol placed at the start of the enclave image by the linker script. + * Declare this extern symbol with visibility "hidden" to ensure the compiler + * does not access it through the GOT and generates position-independent + * addressing as __encl_base(%rip), so we can get the actual enclave base + * during runtime. + */ +extern const uint8_t __attribute__((visibility("hidden"))) __encl_base; + +typedef void (*encl_op_t)(void *); +static const encl_op_t encl_op_array[ENCL_OP_MAX] = { + do_encl_op_put_to_buf, + do_encl_op_get_from_buf, + do_encl_op_put_to_addr, + do_encl_op_get_from_addr, + do_encl_op_nop, + do_encl_eaccept, + do_encl_emodpe, + do_encl_init_tcs_page, +}; + void encl_body(void *rdi, void *rsi) { - const void (*encl_op_array[ENCL_OP_MAX])(void *) = { - do_encl_op_put_to_buf, - do_encl_op_get_from_buf, - do_encl_op_put_to_addr, - do_encl_op_get_from_addr, - do_encl_op_nop, - do_encl_eaccept, - do_encl_emodpe, - do_encl_init_tcs_page, - }; - - struct encl_op_header *op = (struct encl_op_header *)rdi; - - if (op->type < ENCL_OP_MAX) - (*encl_op_array[op->type])(op); + struct encl_op_header *header = (struct encl_op_header *)rdi; + encl_op_t op; + + if (header->type >= ENCL_OP_MAX) + return; + + /* + * The enclave base address needs to be added, as this call site + * *cannot be* made rip-relative by the compiler, or fixed up by + * any other possible means. + */ + op = ((uint64_t)&__encl_base) + encl_op_array[header->type]; + + (*op)(header); } diff --git a/tools/testing/selftests/sgx/test_encl.lds b/tools/testing/selftests/sgx/test_encl.lds index a1ec64f7d91f..ffe851a1cac4 100644 --- a/tools/testing/selftests/sgx/test_encl.lds +++ b/tools/testing/selftests/sgx/test_encl.lds @@ -10,6 +10,7 @@ PHDRS SECTIONS { . = 0; + __encl_base = .; .tcs : { *(.tcs*) } : tcs @@ -23,6 +24,7 @@ SECTIONS } : text .data : { + *(.data.encl_buffer) *(.data*) } : data @@ -31,11 +33,9 @@ SECTIONS *(.note*) *(.debug*) *(.eh_frame*) + *(.dyn*) + *(.gnu.hash) } } -ASSERT(!DEFINED(.altinstructions), "ALTERNATIVES are not supported in enclaves") -ASSERT(!DEFINED(.altinstr_replacement), "ALTERNATIVES are not supported in enclaves") -ASSERT(!DEFINED(.discard.retpoline_safe), "RETPOLINE ALTERNATIVES are not supported in enclaves") -ASSERT(!DEFINED(.discard.nospec), "RETPOLINE ALTERNATIVES are not supported in enclaves") -ASSERT(!DEFINED(.got.plt), "Libcalls are not supported in enclaves") +ASSERT(!DEFINED(_GLOBAL_OFFSET_TABLE_), "Libcalls through GOT are not supported in enclaves") diff --git a/tools/testing/selftests/sgx/test_encl_bootstrap.S b/tools/testing/selftests/sgx/test_encl_bootstrap.S index 03ae0f57e29d..d8c4ac94e032 100644 --- a/tools/testing/selftests/sgx/test_encl_bootstrap.S +++ b/tools/testing/selftests/sgx/test_encl_bootstrap.S @@ -42,9 +42,12 @@ encl_entry: # RBX contains the base address for TCS, which is the first address # inside the enclave for TCS #1 and one page into the enclave for - # TCS #2. By adding the value of encl_stack to it, we get - # the absolute address for the stack. - lea (encl_stack)(%rbx), %rax + # TCS #2. First make it relative by substracting __encl_base and + # then add the address of encl_stack to get the address for the stack. + lea __encl_base(%rip), %rax + sub %rax, %rbx + lea encl_stack(%rip), %rax + add %rbx, %rax jmp encl_entry_core encl_dyn_entry: # Entry point for dynamically created TCS page expected to follow @@ -55,25 +58,12 @@ encl_entry_core: push %rax push %rcx # push the address after EENTER - push %rbx # push the enclave base address + # NOTE: as the selftest enclave is *not* intended for production, + # simplify the code by not initializing ABI registers on entry or + # cleansing caller-save registers on exit. call encl_body - pop %rbx # pop the enclave base address - - /* Clear volatile GPRs, except RAX (EEXIT function). */ - xor %rcx, %rcx - xor %rdx, %rdx - xor %rdi, %rdi - xor %rsi, %rsi - xor %r8, %r8 - xor %r9, %r9 - xor %r10, %r10 - xor %r11, %r11 - - # Reset status flags. - add %rdx, %rdx # OF = SF = AF = CF = 0; ZF = PF = 1 - # Prepare EEXIT target by popping the address of the instruction after # EENTER to RBX. pop %rbx |