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// SPDX-License-Identifier: GPL-2.0
/* Copyright(c) 2016-20 Intel Corporation. */
#include <elf.h>
#include <errno.h>
#include <fcntl.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdint.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/ioctl.h>
#include <sys/mman.h>
#include <sys/stat.h>
#include <sys/time.h>
#include <sys/types.h>
#include <sys/auxv.h>
#include "defines.h"
#include "../kselftest_harness.h"
#include "main.h"
static const uint64_t MAGIC = 0x1122334455667788ULL;
vdso_sgx_enter_enclave_t vdso_sgx_enter_enclave;
struct vdso_symtab {
Elf64_Sym *elf_symtab;
const char *elf_symstrtab;
Elf64_Word *elf_hashtab;
};
static Elf64_Dyn *vdso_get_dyntab(void *addr)
{
Elf64_Ehdr *ehdr = addr;
Elf64_Phdr *phdrtab = addr + ehdr->e_phoff;
int i;
for (i = 0; i < ehdr->e_phnum; i++)
if (phdrtab[i].p_type == PT_DYNAMIC)
return addr + phdrtab[i].p_offset;
return NULL;
}
static void *vdso_get_dyn(void *addr, Elf64_Dyn *dyntab, Elf64_Sxword tag)
{
int i;
for (i = 0; dyntab[i].d_tag != DT_NULL; i++)
if (dyntab[i].d_tag == tag)
return addr + dyntab[i].d_un.d_ptr;
return NULL;
}
static bool vdso_get_symtab(void *addr, struct vdso_symtab *symtab)
{
Elf64_Dyn *dyntab = vdso_get_dyntab(addr);
symtab->elf_symtab = vdso_get_dyn(addr, dyntab, DT_SYMTAB);
if (!symtab->elf_symtab)
return false;
symtab->elf_symstrtab = vdso_get_dyn(addr, dyntab, DT_STRTAB);
if (!symtab->elf_symstrtab)
return false;
symtab->elf_hashtab = vdso_get_dyn(addr, dyntab, DT_HASH);
if (!symtab->elf_hashtab)
return false;
return true;
}
static unsigned long elf_sym_hash(const char *name)
{
unsigned long h = 0, high;
while (*name) {
h = (h << 4) + *name++;
high = h & 0xf0000000;
if (high)
h ^= high >> 24;
h &= ~high;
}
return h;
}
static Elf64_Sym *vdso_symtab_get(struct vdso_symtab *symtab, const char *name)
{
Elf64_Word bucketnum = symtab->elf_hashtab[0];
Elf64_Word *buckettab = &symtab->elf_hashtab[2];
Elf64_Word *chaintab = &symtab->elf_hashtab[2 + bucketnum];
Elf64_Sym *sym;
Elf64_Word i;
for (i = buckettab[elf_sym_hash(name) % bucketnum]; i != STN_UNDEF;
i = chaintab[i]) {
sym = &symtab->elf_symtab[i];
if (!strcmp(name, &symtab->elf_symstrtab[sym->st_name]))
return sym;
}
return NULL;
}
FIXTURE(enclave) {
struct encl encl;
struct sgx_enclave_run run;
};
FIXTURE_SETUP(enclave)
{
Elf64_Sym *sgx_enter_enclave_sym = NULL;
struct vdso_symtab symtab;
struct encl_segment *seg;
char maps_line[256];
FILE *maps_file;
unsigned int i;
void *addr;
if (!encl_load("test_encl.elf", &self->encl)) {
encl_delete(&self->encl);
ksft_exit_skip("cannot load enclaves\n");
}
for (i = 0; i < self->encl.nr_segments; i++) {
seg = &self->encl.segment_tbl[i];
TH_LOG("0x%016lx 0x%016lx 0x%02x", seg->offset, seg->size, seg->prot);
}
if (!encl_measure(&self->encl))
goto err;
if (!encl_build(&self->encl))
goto err;
/*
* An enclave consumer only must do this.
*/
for (i = 0; i < self->encl.nr_segments; i++) {
struct encl_segment *seg = &self->encl.segment_tbl[i];
addr = mmap((void *)self->encl.encl_base + seg->offset, seg->size,
seg->prot, MAP_SHARED | MAP_FIXED, self->encl.fd, 0);
EXPECT_NE(addr, MAP_FAILED);
if (addr == MAP_FAILED)
goto err;
}
/* Get vDSO base address */
addr = (void *)getauxval(AT_SYSINFO_EHDR);
if (!addr)
goto err;
if (!vdso_get_symtab(addr, &symtab))
goto err;
sgx_enter_enclave_sym = vdso_symtab_get(&symtab, "__vdso_sgx_enter_enclave");
if (!sgx_enter_enclave_sym)
goto err;
vdso_sgx_enter_enclave = addr + sgx_enter_enclave_sym->st_value;
memset(&self->run, 0, sizeof(self->run));
self->run.tcs = self->encl.encl_base;
maps_file = fopen("/proc/self/maps", "r");
if (maps_file != NULL) {
while (fgets(maps_line, sizeof(maps_line), maps_file) != NULL) {
maps_line[strlen(maps_line) - 1] = '\0';
if (strstr(maps_line, "/dev/sgx_enclave"))
TH_LOG("%s", maps_line);
}
fclose(maps_file);
}
err:
if (!sgx_enter_enclave_sym)
encl_delete(&self->encl);
ASSERT_NE(sgx_enter_enclave_sym, NULL);
}
FIXTURE_TEARDOWN(enclave)
{
encl_delete(&self->encl);
}
#define ENCL_CALL(op, run, clobbered) \
({ \
int ret; \
if ((clobbered)) \
ret = vdso_sgx_enter_enclave((unsigned long)(op), 0, 0, \
EENTER, 0, 0, (run)); \
else \
ret = sgx_enter_enclave((void *)(op), NULL, 0, EENTER, NULL, NULL, \
(run)); \
ret; \
})
#define EXPECT_EEXIT(run) \
do { \
EXPECT_EQ((run)->function, EEXIT); \
if ((run)->function != EEXIT) \
TH_LOG("0x%02x 0x%02x 0x%016llx", (run)->exception_vector, \
(run)->exception_error_code, (run)->exception_addr); \
} while (0)
TEST_F(enclave, unclobbered_vdso)
{
struct encl_op op;
op.type = ENCL_OP_PUT;
op.buffer = MAGIC;
EXPECT_EQ(ENCL_CALL(&op, &self->run, false), 0);
EXPECT_EEXIT(&self->run);
EXPECT_EQ(self->run.user_data, 0);
op.type = ENCL_OP_GET;
op.buffer = 0;
EXPECT_EQ(ENCL_CALL(&op, &self->run, false), 0);
EXPECT_EQ(op.buffer, MAGIC);
EXPECT_EEXIT(&self->run);
EXPECT_EQ(self->run.user_data, 0);
}
TEST_F(enclave, clobbered_vdso)
{
struct encl_op op;
op.type = ENCL_OP_PUT;
op.buffer = MAGIC;
EXPECT_EQ(ENCL_CALL(&op, &self->run, true), 0);
EXPECT_EEXIT(&self->run);
EXPECT_EQ(self->run.user_data, 0);
op.type = ENCL_OP_GET;
op.buffer = 0;
EXPECT_EQ(ENCL_CALL(&op, &self->run, true), 0);
EXPECT_EQ(op.buffer, MAGIC);
EXPECT_EEXIT(&self->run);
EXPECT_EQ(self->run.user_data, 0);
}
static int test_handler(long rdi, long rsi, long rdx, long ursp, long r8, long r9,
struct sgx_enclave_run *run)
{
run->user_data = 0;
return 0;
}
TEST_F(enclave, clobbered_vdso_and_user_function)
{
struct encl_op op;
self->run.user_handler = (__u64)test_handler;
self->run.user_data = 0xdeadbeef;
op.type = ENCL_OP_PUT;
op.buffer = MAGIC;
EXPECT_EQ(ENCL_CALL(&op, &self->run, true), 0);
EXPECT_EEXIT(&self->run);
EXPECT_EQ(self->run.user_data, 0);
op.type = ENCL_OP_GET;
op.buffer = 0;
EXPECT_EQ(ENCL_CALL(&op, &self->run, true), 0);
EXPECT_EQ(op.buffer, MAGIC);
EXPECT_EEXIT(&self->run);
EXPECT_EQ(self->run.user_data, 0);
}
TEST_HARNESS_MAIN
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