// SPDX-License-Identifier: GPL-2.0
/*  Copyright(c) 2016-20 Intel Corporation. */

#include <cpuid.h>
#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;
static const uint64_t MAGIC2 = 0x8877665544332211ULL;
vdso_sgx_enter_enclave_t vdso_sgx_enter_enclave;

/*
 * Security Information (SECINFO) data structure needed by a few SGX
 * instructions (eg. ENCLU[EACCEPT] and ENCLU[EMODPE]) holds meta-data
 * about an enclave page. &enum sgx_secinfo_page_state specifies the
 * secinfo flags used for page state.
 */
enum sgx_secinfo_page_state {
        SGX_SECINFO_PENDING = (1 << 3),
        SGX_SECINFO_MODIFIED = (1 << 4),
        SGX_SECINFO_PR = (1 << 5),
};

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 inline int sgx2_supported(void)
{
        unsigned int eax, ebx, ecx, edx;

        __cpuid_count(SGX_CPUID, 0x0, eax, ebx, ecx, edx);

        return eax & 0x2;
}

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;
}

/*
 * Return the offset in the enclave where the TCS segment can be found.
 * The first RW segment loaded is the TCS.
 */
static off_t encl_get_tcs_offset(struct encl *encl)
{
        int i;

        for (i = 0; i < encl->nr_segments; i++) {
                struct encl_segment *seg = &encl->segment_tbl[i];

                if (i == 0 && seg->prot == (PROT_READ | PROT_WRITE))
                        return seg->offset;
        }

        return -1;
}

/*
 * Return the offset in the enclave where the data segment can be found.
 * The first RW segment loaded is the TCS, skip that to get info on the
 * data segment.
 */
static off_t encl_get_data_offset(struct encl *encl)
{
        int i;

        for (i = 1; i < encl->nr_segments; i++) {
                struct encl_segment *seg = &encl->segment_tbl[i];

                if (seg->prot == (PROT_READ | PROT_WRITE))
                        return seg->offset;
        }

        return -1;
}

FIXTURE(enclave) {
        struct encl encl;
        struct sgx_enclave_run run;
};

static bool setup_test_encl(unsigned long heap_size, struct encl *encl,
                            struct __test_metadata *_metadata)
{
        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", encl, heap_size)) {
                encl_delete(encl);
                TH_LOG("Failed to load the test enclave.");
                return false;
        }

        if (!encl_measure(encl))
                goto err;

        if (!encl_build(encl))
                goto err;

        /*
         * An enclave consumer only must do this.
         */
        for (i = 0; i < encl->nr_segments; i++) {
                struct encl_segment *seg = &encl->segment_tbl[i];

                addr = mmap((void *)encl->encl_base + seg->offset, seg->size,
                            seg->prot, MAP_SHARED | MAP_FIXED, 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;

        return true;

err:
        for (i = 0; i < encl->nr_segments; i++) {
                seg = &encl->segment_tbl[i];

                TH_LOG("0x%016lx 0x%016lx 0x%02x", seg->offset, seg->size, seg->prot);
        }

        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);
        }

        TH_LOG("Failed to initialize the test enclave.");

        encl_delete(encl);

        return false;
}

FIXTURE_SETUP(enclave)
{
}

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_get_from_buf get_op;
        struct encl_op_put_to_buf put_op;

        ASSERT_TRUE(setup_test_encl(ENCL_HEAP_SIZE_DEFAULT, &self->encl, _metadata));

        memset(&self->run, 0, sizeof(self->run));
        self->run.tcs = self->encl.encl_base;

        put_op.header.type = ENCL_OP_PUT_TO_BUFFER;
        put_op.value = MAGIC;

        EXPECT_EQ(ENCL_CALL(&put_op, &self->run, false), 0);

        EXPECT_EEXIT(&self->run);
        EXPECT_EQ(self->run.user_data, 0);

        get_op.header.type = ENCL_OP_GET_FROM_BUFFER;
        get_op.value = 0;

        EXPECT_EQ(ENCL_CALL(&get_op, &self->run, false), 0);

        EXPECT_EQ(get_op.value, MAGIC);
        EXPECT_EEXIT(&self->run);
        EXPECT_EQ(self->run.user_data, 0);
}

/*
 * A section metric is concatenated in a way that @low bits 12-31 define the
 * bits 12-31 of the metric and @high bits 0-19 define the bits 32-51 of the
 * metric.
 */
static unsigned long sgx_calc_section_metric(unsigned int low,
                                             unsigned int high)
{
        return (low & GENMASK_ULL(31, 12)) +
               ((high & GENMASK_ULL(19, 0)) << 32);
}

/*
 * Sum total available physical SGX memory across all EPC sections
 *
 * Return: total available physical SGX memory available on system
 */
static unsigned long get_total_epc_mem(void)
{
        unsigned int eax, ebx, ecx, edx;
        unsigned long total_size = 0;
        unsigned int type;
        int section = 0;

        while (true) {
                __cpuid_count(SGX_CPUID, section + SGX_CPUID_EPC, eax, ebx, ecx, edx);

                type = eax & SGX_CPUID_EPC_MASK;
                if (type == SGX_CPUID_EPC_INVALID)
                        break;

                if (type != SGX_CPUID_EPC_SECTION)
                        break;

                total_size += sgx_calc_section_metric(ecx, edx);

                section++;
        }

        return total_size;
}

TEST_F(enclave, unclobbered_vdso_oversubscribed)
{
        struct encl_op_get_from_buf get_op;
        struct encl_op_put_to_buf put_op;
        unsigned long total_mem;

        total_mem = get_total_epc_mem();
        ASSERT_NE(total_mem, 0);
        ASSERT_TRUE(setup_test_encl(total_mem, &self->encl, _metadata));

        memset(&self->run, 0, sizeof(self->run));
        self->run.tcs = self->encl.encl_base;

        put_op.header.type = ENCL_OP_PUT_TO_BUFFER;
        put_op.value = MAGIC;

        EXPECT_EQ(ENCL_CALL(&put_op, &self->run, false), 0);

        EXPECT_EEXIT(&self->run);
        EXPECT_EQ(self->run.user_data, 0);

        get_op.header.type = ENCL_OP_GET_FROM_BUFFER;
        get_op.value = 0;

        EXPECT_EQ(ENCL_CALL(&get_op, &self->run, false), 0);

        EXPECT_EQ(get_op.value, MAGIC);
        EXPECT_EEXIT(&self->run);
        EXPECT_EQ(self->run.user_data, 0);
}

TEST_F_TIMEOUT(enclave, unclobbered_vdso_oversubscribed_remove, 900)
{
        struct sgx_enclave_remove_pages remove_ioc;
        struct sgx_enclave_modify_types modt_ioc;
        struct encl_op_get_from_buf get_op;
        struct encl_op_eaccept eaccept_op;
        struct encl_op_put_to_buf put_op;
        struct encl_segment *heap;
        unsigned long total_mem;
        int ret, errno_save;
        unsigned long addr;
        unsigned long i;

        /*
         * Create enclave with additional heap that is as big as all
         * available physical SGX memory.
         */
        total_mem = get_total_epc_mem();
        ASSERT_NE(total_mem, 0);
        TH_LOG("Creating an enclave with %lu bytes heap may take a while ...",
               total_mem);
        ASSERT_TRUE(setup_test_encl(total_mem, &self->encl, _metadata));

        /*
         * Hardware (SGX2) and kernel support is needed for this test. Start
         * with check that test has a chance of succeeding.
         */
        memset(&modt_ioc, 0, sizeof(modt_ioc));
        ret = ioctl(self->encl.fd, SGX_IOC_ENCLAVE_MODIFY_TYPES, &modt_ioc);

        if (ret == -1) {
                if (errno == ENOTTY)
                        SKIP(return,
                             "Kernel does not support SGX_IOC_ENCLAVE_MODIFY_TYPES ioctl()");
                else if (errno == ENODEV)
                        SKIP(return, "System does not support SGX2");
        }

        /*
         * Invalid parameters were provided during sanity check,
         * expect command to fail.
         */
        EXPECT_EQ(ret, -1);

        /* SGX2 is supported by kernel and hardware, test can proceed. */
        memset(&self->run, 0, sizeof(self->run));
        self->run.tcs = self->encl.encl_base;

        heap = &self->encl.segment_tbl[self->encl.nr_segments - 1];

        put_op.header.type = ENCL_OP_PUT_TO_BUFFER;
        put_op.value = MAGIC;

        EXPECT_EQ(ENCL_CALL(&put_op, &self->run, false), 0);

        EXPECT_EEXIT(&self->run);
        EXPECT_EQ(self->run.user_data, 0);

        get_op.header.type = ENCL_OP_GET_FROM_BUFFER;
        get_op.value = 0;

        EXPECT_EQ(ENCL_CALL(&get_op, &self->run, false), 0);

        EXPECT_EQ(get_op.value, MAGIC);
        EXPECT_EEXIT(&self->run);
        EXPECT_EQ(self->run.user_data, 0);

        /* Trim entire heap. */
        memset(&modt_ioc, 0, sizeof(modt_ioc));

        modt_ioc.offset = heap->offset;
        modt_ioc.length = heap->size;
        modt_ioc.page_type = SGX_PAGE_TYPE_TRIM;

        TH_LOG("Changing type of %zd bytes to trimmed may take a while ...",
               heap->size);
        ret = ioctl(self->encl.fd, SGX_IOC_ENCLAVE_MODIFY_TYPES, &modt_ioc);
        errno_save = ret == -1 ? errno : 0;

        EXPECT_EQ(ret, 0);
        EXPECT_EQ(errno_save, 0);
        EXPECT_EQ(modt_ioc.result, 0);
        EXPECT_EQ(modt_ioc.count, heap->size);

        /* EACCEPT all removed pages. */
        addr = self->encl.encl_base + heap->offset;

        eaccept_op.flags = SGX_SECINFO_TRIM | SGX_SECINFO_MODIFIED;
        eaccept_op.header.type = ENCL_OP_EACCEPT;

        TH_LOG("Entering enclave to run EACCEPT for each page of %zd bytes may take a while ...",
               heap->size);
        for (i = 0; i < heap->size; i += 4096) {
                eaccept_op.epc_addr = addr + i;
                eaccept_op.ret = 0;

                EXPECT_EQ(ENCL_CALL(&eaccept_op, &self->run, true), 0);

                EXPECT_EQ(self->run.exception_vector, 0);
                EXPECT_EQ(self->run.exception_error_code, 0);
                EXPECT_EQ(self->run.exception_addr, 0);
                ASSERT_EQ(eaccept_op.ret, 0);
                ASSERT_EQ(self->run.function, EEXIT);
        }

        /* Complete page removal. */
        memset(&remove_ioc, 0, sizeof(remove_ioc));

        remove_ioc.offset = heap->offset;
        remove_ioc.length = heap->size;

        TH_LOG("Removing %zd bytes from enclave may take a while ...",
               heap->size);
        ret = ioctl(self->encl.fd, SGX_IOC_ENCLAVE_REMOVE_PAGES, &remove_ioc);
        errno_save = ret == -1 ? errno : 0;

        EXPECT_EQ(ret, 0);
        EXPECT_EQ(errno_save, 0);
        EXPECT_EQ(remove_ioc.count, heap->size);
}

TEST_F(enclave, clobbered_vdso)
{
        struct encl_op_get_from_buf get_op;
        struct encl_op_put_to_buf put_op;

        ASSERT_TRUE(setup_test_encl(ENCL_HEAP_SIZE_DEFAULT, &self->encl, _metadata));

        memset(&self->run, 0, sizeof(self->run));
        self->run.tcs = self->encl.encl_base;

        put_op.header.type = ENCL_OP_PUT_TO_BUFFER;
        put_op.value = MAGIC;

        EXPECT_EQ(ENCL_CALL(&put_op, &self->run, true), 0);

        EXPECT_EEXIT(&self->run);
        EXPECT_EQ(self->run.user_data, 0);

        get_op.header.type = ENCL_OP_GET_FROM_BUFFER;
        get_op.value = 0;

        EXPECT_EQ(ENCL_CALL(&get_op, &self->run, true), 0);

        EXPECT_EQ(get_op.value, 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_get_from_buf get_op;
        struct encl_op_put_to_buf put_op;

        ASSERT_TRUE(setup_test_encl(ENCL_HEAP_SIZE_DEFAULT, &self->encl, _metadata));

        memset(&self->run, 0, sizeof(self->run));
        self->run.tcs = self->encl.encl_base;

        self->run.user_handler = (__u64)test_handler;
        self->run.user_data = 0xdeadbeef;

        put_op.header.type = ENCL_OP_PUT_TO_BUFFER;
        put_op.value = MAGIC;

        EXPECT_EQ(ENCL_CALL(&put_op, &self->run, true), 0);

        EXPECT_EEXIT(&self->run);
        EXPECT_EQ(self->run.user_data, 0);

        get_op.header.type = ENCL_OP_GET_FROM_BUFFER;
        get_op.value = 0;

        EXPECT_EQ(ENCL_CALL(&get_op, &self->run, true), 0);

        EXPECT_EQ(get_op.value, MAGIC);
        EXPECT_EEXIT(&self->run);
        EXPECT_EQ(self->run.user_data, 0);
}

/*
 * Sanity check that it is possible to enter either of the two hardcoded TCS
 */
TEST_F(enclave, tcs_entry)
{
        struct encl_op_header op;

        ASSERT_TRUE(setup_test_encl(ENCL_HEAP_SIZE_DEFAULT, &self->encl, _metadata));

        memset(&self->run, 0, sizeof(self->run));
        self->run.tcs = self->encl.encl_base;

        op.type = ENCL_OP_NOP;

        EXPECT_EQ(ENCL_CALL(&op, &self->run, true), 0);

        EXPECT_EEXIT(&self->run);
        EXPECT_EQ(self->run.exception_vector, 0);
        EXPECT_EQ(self->run.exception_error_code, 0);
        EXPECT_EQ(self->run.exception_addr, 0);

        /* Move to the next TCS. */
        self->run.tcs = self->encl.encl_base + PAGE_SIZE;

        EXPECT_EQ(ENCL_CALL(&op, &self->run, true), 0);

        EXPECT_EEXIT(&self->run);
        EXPECT_EQ(self->run.exception_vector, 0);
        EXPECT_EQ(self->run.exception_error_code, 0);
        EXPECT_EQ(self->run.exception_addr, 0);
}

/*
 * Second page of .data segment is used to test changing PTE permissions.
 * This spans the local encl_buffer within the test enclave.
 *
 * 1) Start with a sanity check: a value is written to the target page within
 *    the enclave and read back to ensure target page can be written to.
 * 2) Change PTE permissions (RW -> RO) of target page within enclave.
 * 3) Repeat (1) - this time expecting a regular #PF communicated via the
 *    vDSO.
 * 4) Change PTE permissions of target page within enclave back to be RW.
 * 5) Repeat (1) by resuming enclave, now expected to be possible to write to
 *    and read from target page within enclave.
 */
TEST_F(enclave, pte_permissions)
{
        struct encl_op_get_from_addr get_addr_op;
        struct encl_op_put_to_addr put_addr_op;
        unsigned long data_start;
        int ret;

        ASSERT_TRUE(setup_test_encl(ENCL_HEAP_SIZE_DEFAULT, &self->encl, _metadata));

        memset(&self->run, 0, sizeof(self->run));
        self->run.tcs = self->encl.encl_base;

        data_start = self->encl.encl_base +
                     encl_get_data_offset(&self->encl) +
                     PAGE_SIZE;

        /*
         * Sanity check to ensure it is possible to write to page that will
         * have its permissions manipulated.
         */

        /* Write MAGIC to page */
        put_addr_op.value = MAGIC;
        put_addr_op.addr = data_start;
        put_addr_op.header.type = ENCL_OP_PUT_TO_ADDRESS;

        EXPECT_EQ(ENCL_CALL(&put_addr_op, &self->run, true), 0);

        EXPECT_EEXIT(&self->run);
        EXPECT_EQ(self->run.exception_vector, 0);
        EXPECT_EQ(self->run.exception_error_code, 0);
        EXPECT_EQ(self->run.exception_addr, 0);

        /*
         * Read memory that was just written to, confirming that it is the
         * value previously written (MAGIC).
         */
        get_addr_op.value = 0;
        get_addr_op.addr = data_start;
        get_addr_op.header.type = ENCL_OP_GET_FROM_ADDRESS;

        EXPECT_EQ(ENCL_CALL(&get_addr_op, &self->run, true), 0);

        EXPECT_EQ(get_addr_op.value, MAGIC);
        EXPECT_EEXIT(&self->run);
        EXPECT_EQ(self->run.exception_vector, 0);
        EXPECT_EQ(self->run.exception_error_code, 0);
        EXPECT_EQ(self->run.exception_addr, 0);

        /* Change PTE permissions of target page within the enclave */
        ret = mprotect((void *)data_start, PAGE_SIZE, PROT_READ);
        if (ret)
                perror("mprotect");

        /*
         * PTE permissions of target page changed to read-only, EPCM
         * permissions unchanged (EPCM permissions are RW), attempt to
         * write to the page, expecting a regular #PF.
         */

        put_addr_op.value = MAGIC2;

        EXPECT_EQ(ENCL_CALL(&put_addr_op, &self->run, true), 0);

        EXPECT_EQ(self->run.exception_vector, 14);
        EXPECT_EQ(self->run.exception_error_code, 0x7);
        EXPECT_EQ(self->run.exception_addr, data_start);

        self->run.exception_vector = 0;
        self->run.exception_error_code = 0;
        self->run.exception_addr = 0;

        /*
         * Change PTE permissions back to enable enclave to write to the
         * target page and resume enclave - do not expect any exceptions this
         * time.
         */
        ret = mprotect((void *)data_start, PAGE_SIZE, PROT_READ | PROT_WRITE);
        if (ret)
                perror("mprotect");

        EXPECT_EQ(vdso_sgx_enter_enclave((unsigned long)&put_addr_op, 0,
                                         0, ERESUME, 0, 0, &self->run),
                 0);

        EXPECT_EEXIT(&self->run);
        EXPECT_EQ(self->run.exception_vector, 0);
        EXPECT_EQ(self->run.exception_error_code, 0);
        EXPECT_EQ(self->run.exception_addr, 0);

        get_addr_op.value = 0;

        EXPECT_EQ(ENCL_CALL(&get_addr_op, &self->run, true), 0);

        EXPECT_EQ(get_addr_op.value, MAGIC2);
        EXPECT_EEXIT(&self->run);
        EXPECT_EQ(self->run.exception_vector, 0);
        EXPECT_EQ(self->run.exception_error_code, 0);
        EXPECT_EQ(self->run.exception_addr, 0);
}

/*
 * Modifying permissions of TCS page should not be possible.
 */
TEST_F(enclave, tcs_permissions)
{
        struct sgx_enclave_restrict_permissions ioc;
        int ret, errno_save;

        ASSERT_TRUE(setup_test_encl(ENCL_HEAP_SIZE_DEFAULT, &self->encl, _metadata));

        memset(&self->run, 0, sizeof(self->run));
        self->run.tcs = self->encl.encl_base;

        memset(&ioc, 0, sizeof(ioc));

        /*
         * Ensure kernel supports needed ioctl() and system supports needed
         * commands.
         */

        ret = ioctl(self->encl.fd, SGX_IOC_ENCLAVE_RESTRICT_PERMISSIONS, &ioc);
        errno_save = ret == -1 ? errno : 0;

        /*
         * Invalid parameters were provided during sanity check,
         * expect command to fail.
         */
        ASSERT_EQ(ret, -1);

        /* ret == -1 */
        if (errno_save == ENOTTY)
                SKIP(return,
                     "Kernel does not support SGX_IOC_ENCLAVE_RESTRICT_PERMISSIONS ioctl()");
        else if (errno_save == ENODEV)
                SKIP(return, "System does not support SGX2");

        /*
         * Attempt to make TCS page read-only. This is not allowed and
         * should be prevented by the kernel.
         */
        ioc.offset = encl_get_tcs_offset(&self->encl);
        ioc.length = PAGE_SIZE;
        ioc.permissions = SGX_SECINFO_R;

        ret = ioctl(self->encl.fd, SGX_IOC_ENCLAVE_RESTRICT_PERMISSIONS, &ioc);
        errno_save = ret == -1 ? errno : 0;

        EXPECT_EQ(ret, -1);
        EXPECT_EQ(errno_save, EINVAL);
        EXPECT_EQ(ioc.result, 0);
        EXPECT_EQ(ioc.count, 0);
}

/*
 * Enclave page permission test.
 *
 * Modify and restore enclave page's EPCM (enclave) permissions from
 * outside enclave (ENCLS[EMODPR] via kernel) as well as from within
 * enclave (via ENCLU[EMODPE]). Check for page fault if
 * VMA allows access but EPCM permissions do not.
 */
TEST_F(enclave, epcm_permissions)
{
        struct sgx_enclave_restrict_permissions restrict_ioc;
        struct encl_op_get_from_addr get_addr_op;
        struct encl_op_put_to_addr put_addr_op;
        struct encl_op_eaccept eaccept_op;
        struct encl_op_emodpe emodpe_op;
        unsigned long data_start;
        int ret, errno_save;

        ASSERT_TRUE(setup_test_encl(ENCL_HEAP_SIZE_DEFAULT, &self->encl, _metadata));

        memset(&self->run, 0, sizeof(self->run));
        self->run.tcs = self->encl.encl_base;

        /*
         * Ensure kernel supports needed ioctl() and system supports needed
         * commands.
         */
        memset(&restrict_ioc, 0, sizeof(restrict_ioc));

        ret = ioctl(self->encl.fd, SGX_IOC_ENCLAVE_RESTRICT_PERMISSIONS,
                    &restrict_ioc);
        errno_save = ret == -1 ? errno : 0;

        /*
         * Invalid parameters were provided during sanity check,
         * expect command to fail.
         */
        ASSERT_EQ(ret, -1);

        /* ret == -1 */
        if (errno_save == ENOTTY)
                SKIP(return,
                     "Kernel does not support SGX_IOC_ENCLAVE_RESTRICT_PERMISSIONS ioctl()");
        else if (errno_save == ENODEV)
                SKIP(return, "System does not support SGX2");

        /*
         * Page that will have its permissions changed is the second data
         * page in the .data segment. This forms part of the local encl_buffer
         * within the enclave.
         *
         * At start of test @data_start should have EPCM as well as PTE and
         * VMA permissions of RW.
         */

        data_start = self->encl.encl_base +
                     encl_get_data_offset(&self->encl) + PAGE_SIZE;

        /*
         * Sanity check that page at @data_start is writable before making
         * any changes to page permissions.
         *
         * Start by writing MAGIC to test page.
         */
        put_addr_op.value = MAGIC;
        put_addr_op.addr = data_start;
        put_addr_op.header.type = ENCL_OP_PUT_TO_ADDRESS;

        EXPECT_EQ(ENCL_CALL(&put_addr_op, &self->run, true), 0);

        EXPECT_EEXIT(&self->run);
        EXPECT_EQ(self->run.exception_vector, 0);
        EXPECT_EQ(self->run.exception_error_code, 0);
        EXPECT_EQ(self->run.exception_addr, 0);

        /*
         * Read memory that was just written to, confirming that
         * page is writable.
         */
        get_addr_op.value = 0;
        get_addr_op.addr = data_start;
        get_addr_op.header.type = ENCL_OP_GET_FROM_ADDRESS;

        EXPECT_EQ(ENCL_CALL(&get_addr_op, &self->run, true), 0);

        EXPECT_EQ(get_addr_op.value, MAGIC);
        EXPECT_EEXIT(&self->run);
        EXPECT_EQ(self->run.exception_vector, 0);
        EXPECT_EQ(self->run.exception_error_code, 0);
        EXPECT_EQ(self->run.exception_addr, 0);

        /*
         * Change EPCM permissions to read-only. Kernel still considers
         * the page writable.
         */
        memset(&restrict_ioc, 0, sizeof(restrict_ioc));

        restrict_ioc.offset = encl_get_data_offset(&self->encl) + PAGE_SIZE;
        restrict_ioc.length = PAGE_SIZE;
        restrict_ioc.permissions = SGX_SECINFO_R;

        ret = ioctl(self->encl.fd, SGX_IOC_ENCLAVE_RESTRICT_PERMISSIONS,
                    &restrict_ioc);
        errno_save = ret == -1 ? errno : 0;

        EXPECT_EQ(ret, 0);
        EXPECT_EQ(errno_save, 0);
        EXPECT_EQ(restrict_ioc.result, 0);
        EXPECT_EQ(restrict_ioc.count, 4096);

        /*
         * EPCM permissions changed from kernel, need to EACCEPT from enclave.
         */
        eaccept_op.epc_addr = data_start;
        eaccept_op.flags = SGX_SECINFO_R | SGX_SECINFO_REG | SGX_SECINFO_PR;
        eaccept_op.ret = 0;
        eaccept_op.header.type = ENCL_OP_EACCEPT;

        EXPECT_EQ(ENCL_CALL(&eaccept_op, &self->run, true), 0);

        EXPECT_EEXIT(&self->run);
        EXPECT_EQ(self->run.exception_vector, 0);
        EXPECT_EQ(self->run.exception_error_code, 0);
        EXPECT_EQ(self->run.exception_addr, 0);
        EXPECT_EQ(eaccept_op.ret, 0);

        /*
         * EPCM permissions of page is now read-only, expect #PF
         * on EPCM when attempting to write to page from within enclave.
         */
        put_addr_op.value = MAGIC2;

        EXPECT_EQ(ENCL_CALL(&put_addr_op, &self->run, true), 0);

        EXPECT_EQ(self->run.function, ERESUME);
        EXPECT_EQ(self->run.exception_vector, 14);
        EXPECT_EQ(self->run.exception_error_code, 0x8007);
        EXPECT_EQ(self->run.exception_addr, data_start);

        self->run.exception_vector = 0;
        self->run.exception_error_code = 0;
        self->run.exception_addr = 0;

        /*
         * Received AEX but cannot return to enclave at same entrypoint,
         * need different TCS from where EPCM permission can be made writable
         * again.
         */
        self->run.tcs = self->encl.encl_base + PAGE_SIZE;

        /*
         * Enter enclave at new TCS to change EPCM permissions to be
         * writable again and thus fix the page fault that triggered the
         * AEX.
         */

        emodpe_op.epc_addr = data_start;
        emodpe_op.flags = SGX_SECINFO_R | SGX_SECINFO_W;
        emodpe_op.header.type = ENCL_OP_EMODPE;

        EXPECT_EQ(ENCL_CALL(&emodpe_op, &self->run, true), 0);

        EXPECT_EEXIT(&self->run);
        EXPECT_EQ(self->run.exception_vector, 0);
        EXPECT_EQ(self->run.exception_error_code, 0);
        EXPECT_EQ(self->run.exception_addr, 0);

        /*
         * Attempt to return to main TCS to resume execution at faulting
         * instruction, PTE should continue to allow writing to the page.
         */
        self->run.tcs = self->encl.encl_base;

        /*
         * Wrong page permissions that caused original fault has
         * now been fixed via EPCM permissions.
         * Resume execution in main TCS to re-attempt the memory access.
         */
        self->run.tcs = self->encl.encl_base;

        EXPECT_EQ(vdso_sgx_enter_enclave((unsigned long)&put_addr_op, 0, 0,
                                         ERESUME, 0, 0,
                                         &self->run),
                  0);

        EXPECT_EEXIT(&self->run);
        EXPECT_EQ(self->run.exception_vector, 0);
        EXPECT_EQ(self->run.exception_error_code, 0);
        EXPECT_EQ(self->run.exception_addr, 0);

        get_addr_op.value = 0;

        EXPECT_EQ(ENCL_CALL(&get_addr_op, &self->run, true), 0);

        EXPECT_EQ(get_addr_op.value, MAGIC2);
        EXPECT_EEXIT(&self->run);
        EXPECT_EQ(self->run.user_data, 0);
        EXPECT_EQ(self->run.exception_vector, 0);
        EXPECT_EQ(self->run.exception_error_code, 0);
        EXPECT_EQ(self->run.exception_addr, 0);
}

/*
 * Test the addition of pages to an initialized enclave via writing to
 * a page belonging to the enclave's address space but was not added
 * during enclave creation.
 */
TEST_F(enclave, augment)
{
        struct encl_op_get_from_addr get_addr_op;
        struct encl_op_put_to_addr put_addr_op;
        struct encl_op_eaccept eaccept_op;
        size_t total_size = 0;
        void *addr;
        int i;

        if (!sgx2_supported())
                SKIP(return, "SGX2 not supported");

        ASSERT_TRUE(setup_test_encl(ENCL_HEAP_SIZE_DEFAULT, &self->encl, _metadata));

        memset(&self->run, 0, sizeof(self->run));
        self->run.tcs = self->encl.encl_base;

        for (i = 0; i < self->encl.nr_segments; i++) {
                struct encl_segment *seg = &self->encl.segment_tbl[i];

                total_size += seg->size;
        }

        /*
         * Actual enclave size is expected to be larger than the loaded
         * test enclave since enclave size must be a power of 2 in bytes
         * and test_encl does not consume it all.
         */
        EXPECT_LT(total_size + PAGE_SIZE, self->encl.encl_size);

        /*
         * Create memory mapping for the page that will be added. New
         * memory mapping is for one page right after all existing
         * mappings.
         * Kernel will allow new mapping using any permissions if it
         * falls into the enclave's address range but not backed
         * by existing enclave pages.
         */
        addr = mmap((void *)self->encl.encl_base + total_size, PAGE_SIZE,
                    PROT_READ | PROT_WRITE | PROT_EXEC,
                    MAP_SHARED | MAP_FIXED, self->encl.fd, 0);
        EXPECT_NE(addr, MAP_FAILED);

        self->run.exception_vector = 0;
        self->run.exception_error_code = 0;
        self->run.exception_addr = 0;

        /*
         * Attempt to write to the new page from within enclave.
         * Expected to fail since page is not (yet) part of the enclave.
         * The first #PF will trigger the addition of the page to the
         * enclave, but since the new page needs an EACCEPT from within the
         * enclave before it can be used it would not be possible
         * to successfully return to the failing instruction. This is the
         * cause of the second #PF captured here having the SGX bit set,
         * it is from hardware preventing the page from being used.
         */
        put_addr_op.value = MAGIC;
        put_addr_op.addr = (unsigned long)addr;
        put_addr_op.header.type = ENCL_OP_PUT_TO_ADDRESS;

        EXPECT_EQ(ENCL_CALL(&put_addr_op, &self->run, true), 0);

        EXPECT_EQ(self->run.function, ERESUME);
        EXPECT_EQ(self->run.exception_vector, 14);
        EXPECT_EQ(self->run.exception_addr, (unsigned long)addr);

        if (self->run.exception_error_code == 0x6) {
                munmap(addr, PAGE_SIZE);
                SKIP(return, "Kernel does not support adding pages to initialized enclave");
        }

        EXPECT_EQ(self->run.exception_error_code, 0x8007);

        self->run.exception_vector = 0;
        self->run.exception_error_code = 0;
        self->run.exception_addr = 0;

        /* Handle AEX by running EACCEPT from new entry point. */
        self->run.tcs = self->encl.encl_base + PAGE_SIZE;

        eaccept_op.epc_addr = self->encl.encl_base + total_size;
        eaccept_op.flags = SGX_SECINFO_R | SGX_SECINFO_W | SGX_SECINFO_REG | SGX_SECINFO_PENDING;
        eaccept_op.ret = 0;
        eaccept_op.header.type = ENCL_OP_EACCEPT;

        EXPECT_EQ(ENCL_CALL(&eaccept_op, &self->run, true), 0);

        EXPECT_EEXIT(&self->run);
        EXPECT_EQ(self->run.exception_vector, 0);
        EXPECT_EQ(self->run.exception_error_code, 0);
        EXPECT_EQ(self->run.exception_addr, 0);
        EXPECT_EQ(eaccept_op.ret, 0);

        /* Can now return to main TCS to resume execution. */
        self->run.tcs = self->encl.encl_base;

        EXPECT_EQ(vdso_sgx_enter_enclave((unsigned long)&put_addr_op, 0, 0,
                                         ERESUME, 0, 0,
                                         &self->run),
                  0);

        EXPECT_EEXIT(&self->run);
        EXPECT_EQ(self->run.exception_vector, 0);
        EXPECT_EQ(self->run.exception_error_code, 0);
        EXPECT_EQ(self->run.exception_addr, 0);

        /*
         * Read memory from newly added page that was just written to,
         * confirming that data previously written (MAGIC) is present.
         */
        get_addr_op.value = 0;
        get_addr_op.addr = (unsigned long)addr;
        get_addr_op.header.type = ENCL_OP_GET_FROM_ADDRESS;

        EXPECT_EQ(ENCL_CALL(&get_addr_op, &self->run, true), 0);

        EXPECT_EQ(get_addr_op.value, MAGIC);
        EXPECT_EEXIT(&self->run);
        EXPECT_EQ(self->run.exception_vector, 0);
        EXPECT_EQ(self->run.exception_error_code, 0);
        EXPECT_EQ(self->run.exception_addr, 0);

        munmap(addr, PAGE_SIZE);
}

/*
 * Test for the addition of pages to an initialized enclave via a
 * pre-emptive run of EACCEPT on page to be added.
 */
TEST_F(enclave, augment_via_eaccept)
{
        struct encl_op_get_from_addr get_addr_op;
        struct encl_op_put_to_addr put_addr_op;
        struct encl_op_eaccept eaccept_op;
        size_t total_size = 0;
        void *addr;
        int i;

        if (!sgx2_supported())
                SKIP(return, "SGX2 not supported");

        ASSERT_TRUE(setup_test_encl(ENCL_HEAP_SIZE_DEFAULT, &self->encl, _metadata));

        memset(&self->run, 0, sizeof(self->run));
        self->run.tcs = self->encl.encl_base;

        for (i = 0; i < self->encl.nr_segments; i++) {
                struct encl_segment *seg = &self->encl.segment_tbl[i];

                total_size += seg->size;
        }

        /*
         * Actual enclave size is expected to be larger than the loaded
         * test enclave since enclave size must be a power of 2 in bytes while
         * test_encl does not consume it all.
         */
        EXPECT_LT(total_size + PAGE_SIZE, self->encl.encl_size);

        /*
         * mmap() a page at end of existing enclave to be used for dynamic
         * EPC page.
         *
         * Kernel will allow new mapping using any permissions if it
         * falls into the enclave's address range but not backed
         * by existing enclave pages.
         */

        addr = mmap((void *)self->encl.encl_base + total_size, PAGE_SIZE,
                    PROT_READ | PROT_WRITE | PROT_EXEC, MAP_SHARED | MAP_FIXED,
                    self->encl.fd, 0);
        EXPECT_NE(addr, MAP_FAILED);

        self->run.exception_vector = 0;
        self->run.exception_error_code = 0;
        self->run.exception_addr = 0;

        /*
         * Run EACCEPT on new page to trigger the #PF->EAUG->EACCEPT(again
         * without a #PF). All should be transparent to userspace.
         */
        eaccept_op.epc_addr = self->encl.encl_base + total_size;
        eaccept_op.flags = SGX_SECINFO_R | SGX_SECINFO_W | SGX_SECINFO_REG | SGX_SECINFO_PENDING;
        eaccept_op.ret = 0;
        eaccept_op.header.type = ENCL_OP_EACCEPT;

        EXPECT_EQ(ENCL_CALL(&eaccept_op, &self->run, true), 0);

        if (self->run.exception_vector == 14 &&
            self->run.exception_error_code == 4 &&
            self->run.exception_addr == self->encl.encl_base + total_size) {
                munmap(addr, PAGE_SIZE);
                SKIP(return, "Kernel does not support adding pages to initialized enclave");
        }

        EXPECT_EEXIT(&self->run);
        EXPECT_EQ(self->run.exception_vector, 0);
        EXPECT_EQ(self->run.exception_error_code, 0);
        EXPECT_EQ(self->run.exception_addr, 0);
        EXPECT_EQ(eaccept_op.ret, 0);

        /*
         * New page should be accessible from within enclave - attempt to
         * write to it.
         */
        put_addr_op.value = MAGIC;
        put_addr_op.addr = (unsigned long)addr;
        put_addr_op.header.type = ENCL_OP_PUT_TO_ADDRESS;

        EXPECT_EQ(ENCL_CALL(&put_addr_op, &self->run, true), 0);

        EXPECT_EEXIT(&self->run);
        EXPECT_EQ(self->run.exception_vector, 0);
        EXPECT_EQ(self->run.exception_error_code, 0);
        EXPECT_EQ(self->run.exception_addr, 0);

        /*
         * Read memory from newly added page that was just written to,
         * confirming that data previously written (MAGIC) is present.
         */
        get_addr_op.value = 0;
        get_addr_op.addr = (unsigned long)addr;
        get_addr_op.header.type = ENCL_OP_GET_FROM_ADDRESS;

        EXPECT_EQ(ENCL_CALL(&get_addr_op, &self->run, true), 0);

        EXPECT_EQ(get_addr_op.value, MAGIC);
        EXPECT_EEXIT(&self->run);
        EXPECT_EQ(self->run.exception_vector, 0);
        EXPECT_EQ(self->run.exception_error_code, 0);
        EXPECT_EQ(self->run.exception_addr, 0);

        munmap(addr, PAGE_SIZE);
}

/*
 * SGX2 page type modification test in two phases:
 * Phase 1:
 * Create a new TCS, consisting out of three new pages (stack page with regular
 * page type, SSA page with regular page type, and TCS page with TCS page
 * type) in an initialized enclave and run a simple workload within it.
 * Phase 2:
 * Remove the three pages added in phase 1, add a new regular page at the
 * same address that previously hosted the TCS page and verify that it can
 * be modified.
 */
TEST_F(enclave, tcs_create)
{
        struct encl_op_init_tcs_page init_tcs_page_op;
        struct sgx_enclave_remove_pages remove_ioc;
        struct encl_op_get_from_addr get_addr_op;
        struct sgx_enclave_modify_types modt_ioc;
        struct encl_op_put_to_addr put_addr_op;
        struct encl_op_get_from_buf get_buf_op;
        struct encl_op_put_to_buf put_buf_op;
        void *addr, *tcs, *stack_end, *ssa;
        struct encl_op_eaccept eaccept_op;
        size_t total_size = 0;
        uint64_t val_64;
        int errno_save;
        int ret, i;

        ASSERT_TRUE(setup_test_encl(ENCL_HEAP_SIZE_DEFAULT, &self->encl,
                                    _metadata));

        memset(&self->run, 0, sizeof(self->run));
        self->run.tcs = self->encl.encl_base;

        /*
         * Hardware (SGX2) and kernel support is needed for this test. Start
         * with check that test has a chance of succeeding.
         */
        memset(&modt_ioc, 0, sizeof(modt_ioc));
        ret = ioctl(self->encl.fd, SGX_IOC_ENCLAVE_MODIFY_TYPES, &modt_ioc);

        if (ret == -1) {
                if (errno == ENOTTY)
                        SKIP(return,
                             "Kernel does not support SGX_IOC_ENCLAVE_MODIFY_TYPES ioctl()");
                else if (errno == ENODEV)
                        SKIP(return, "System does not support SGX2");
        }

        /*
         * Invalid parameters were provided during sanity check,
         * expect command to fail.
         */
        EXPECT_EQ(ret, -1);

        /*
         * Add three regular pages via EAUG: one will be the TCS stack, one
         * will be the TCS SSA, and one will be the new TCS. The stack and
         * SSA will remain as regular pages, the TCS page will need its
         * type changed after populated with needed data.
         */
        for (i = 0; i < self->encl.nr_segments; i++) {
                struct encl_segment *seg = &self->encl.segment_tbl[i];

                total_size += seg->size;
        }

        /*
         * Actual enclave size is expected to be larger than the loaded
         * test enclave since enclave size must be a power of 2 in bytes while
         * test_encl does not consume it all.
         */
        EXPECT_LT(total_size + 3 * PAGE_SIZE, self->encl.encl_size);

        /*
         * mmap() three pages at end of existing enclave to be used for the
         * three new pages.
         */
        addr = mmap((void *)self->encl.encl_base + total_size, 3 * PAGE_SIZE,
                    PROT_READ | PROT_WRITE, MAP_SHARED | MAP_FIXED,
                    self->encl.fd, 0);
        EXPECT_NE(addr, MAP_FAILED);

        self->run.exception_vector = 0;
        self->run.exception_error_code = 0;
        self->run.exception_addr = 0;

        stack_end = (void *)self->encl.encl_base + total_size;
        tcs = (void *)self->encl.encl_base + total_size + PAGE_SIZE;
        ssa = (void *)self->encl.encl_base + total_size + 2 * PAGE_SIZE;

        /*
         * Run EACCEPT on each new page to trigger the
         * EACCEPT->(#PF)->EAUG->EACCEPT(again without a #PF) flow.
         */

        eaccept_op.epc_addr = (unsigned long)stack_end;
        eaccept_op.flags = SGX_SECINFO_R | SGX_SECINFO_W | SGX_SECINFO_REG | SGX_SECINFO_PENDING;
        eaccept_op.ret = 0;
        eaccept_op.header.type = ENCL_OP_EACCEPT;

        EXPECT_EQ(ENCL_CALL(&eaccept_op, &self->run, true), 0);

        if (self->run.exception_vector == 14 &&
            self->run.exception_error_code == 4 &&
            self->run.exception_addr == (unsigned long)stack_end) {
                munmap(addr, 3 * PAGE_SIZE);
                SKIP(return, "Kernel does not support adding pages to initialized enclave");
        }

        EXPECT_EEXIT(&self->run);
        EXPECT_EQ(self->run.exception_vector, 0);
        EXPECT_EQ(self->run.exception_error_code, 0);
        EXPECT_EQ(self->run.exception_addr, 0);
        EXPECT_EQ(eaccept_op.ret, 0);

        eaccept_op.epc_addr = (unsigned long)ssa;

        EXPECT_EQ(ENCL_CALL(&eaccept_op, &self->run, true), 0);

        EXPECT_EEXIT(&self->run);
        EXPECT_EQ(self->run.exception_vector, 0);
        EXPECT_EQ(self->run.exception_error_code, 0);
        EXPECT_EQ(self->run.exception_addr, 0);
        EXPECT_EQ(eaccept_op.ret, 0);

        eaccept_op.epc_addr = (unsigned long)tcs;

        EXPECT_EQ(ENCL_CALL(&eaccept_op, &self->run, true), 0);

        EXPECT_EEXIT(&self->run);
        EXPECT_EQ(self->run.exception_vector, 0);
        EXPECT_EQ(self->run.exception_error_code, 0);
        EXPECT_EQ(self->run.exception_addr, 0);
        EXPECT_EQ(eaccept_op.ret, 0);

        /*
         * Three new pages added to enclave. Now populate the TCS page with
         * needed data. This should be done from within enclave. Provide
         * the function that will do the actual data population with needed
         * data.
         */

        /*
         * New TCS will use the "encl_dyn_entry" entrypoint that expects
         * stack to begin in page before TCS page.
         */
        val_64 = encl_get_entry(&self->encl, "encl_dyn_entry");
        EXPECT_NE(val_64, 0);

        init_tcs_page_op.tcs_page = (unsigned long)tcs;
        init_tcs_page_op.ssa = (unsigned long)total_size + 2 * PAGE_SIZE;
        init_tcs_page_op.entry = val_64;
        init_tcs_page_op.header.type = ENCL_OP_INIT_TCS_PAGE;

        EXPECT_EQ(ENCL_CALL(&init_tcs_page_op, &self->run, true), 0);

        EXPECT_EEXIT(&self->run);
        EXPECT_EQ(self->run.exception_vector, 0);
        EXPECT_EQ(self->run.exception_error_code, 0);
        EXPECT_EQ(self->run.exception_addr, 0);

        /* Change TCS page type to TCS. */
        memset(&modt_ioc, 0, sizeof(modt_ioc));

        modt_ioc.offset = total_size + PAGE_SIZE;
        modt_ioc.length = PAGE_SIZE;
        modt_ioc.page_type = SGX_PAGE_TYPE_TCS;

        ret = ioctl(self->encl.fd, SGX_IOC_ENCLAVE_MODIFY_TYPES, &modt_ioc);
        errno_save = ret == -1 ? errno : 0;

        EXPECT_EQ(ret, 0);
        EXPECT_EQ(errno_save, 0);
        EXPECT_EQ(modt_ioc.result, 0);
        EXPECT_EQ(modt_ioc.count, 4096);

        /* EACCEPT new TCS page from enclave. */
        eaccept_op.epc_addr = (unsigned long)tcs;
        eaccept_op.flags = SGX_SECINFO_TCS | SGX_SECINFO_MODIFIED;
        eaccept_op.ret = 0;
        eaccept_op.header.type = ENCL_OP_EACCEPT;

        EXPECT_EQ(ENCL_CALL(&eaccept_op, &self->run, true), 0);

        EXPECT_EEXIT(&self->run);
        EXPECT_EQ(self->run.exception_vector, 0);
        EXPECT_EQ(self->run.exception_error_code, 0);
        EXPECT_EQ(self->run.exception_addr, 0);
        EXPECT_EQ(eaccept_op.ret, 0);

        /* Run workload from new TCS. */
        self->run.tcs = (unsigned long)tcs;

        /*
         * Simple workload to write to data buffer and read value back.
         */
        put_buf_op.header.type = ENCL_OP_PUT_TO_BUFFER;
        put_buf_op.value = MAGIC;

        EXPECT_EQ(ENCL_CALL(&put_buf_op, &self->run, true), 0);

        EXPECT_EEXIT(&self->run);
        EXPECT_EQ(self->run.exception_vector, 0);
        EXPECT_EQ(self->run.exception_error_code, 0);
        EXPECT_EQ(self->run.exception_addr, 0);

        get_buf_op.header.type = ENCL_OP_GET_FROM_BUFFER;
        get_buf_op.value = 0;

        EXPECT_EQ(ENCL_CALL(&get_buf_op, &self->run, true), 0);

        EXPECT_EQ(get_buf_op.value, MAGIC);
        EXPECT_EEXIT(&self->run);
        EXPECT_EQ(self->run.exception_vector, 0);
        EXPECT_EQ(self->run.exception_error_code, 0);
        EXPECT_EQ(self->run.exception_addr, 0);

        /*
         * Phase 2 of test:
         * Remove pages associated with new TCS, create a regular page
         * where TCS page used to be and verify it can be used as a regular
         * page.
         */

        /* Start page removal by requesting change of page type to PT_TRIM. */
        memset(&modt_ioc, 0, sizeof(modt_ioc));

        modt_ioc.offset = total_size;
        modt_ioc.length = 3 * PAGE_SIZE;
        modt_ioc.page_type = SGX_PAGE_TYPE_TRIM;

        ret = ioctl(self->encl.fd, SGX_IOC_ENCLAVE_MODIFY_TYPES, &modt_ioc);
        errno_save = ret == -1 ? errno : 0;

        EXPECT_EQ(ret, 0);
        EXPECT_EQ(errno_save, 0);
        EXPECT_EQ(modt_ioc.result, 0);
        EXPECT_EQ(modt_ioc.count, 3 * PAGE_SIZE);

        /*
         * Enter enclave via TCS #1 and approve page removal by sending
         * EACCEPT for each of three removed pages.
         */
        self->run.tcs = self->encl.encl_base;

        eaccept_op.epc_addr = (unsigned long)stack_end;
        eaccept_op.flags = SGX_SECINFO_TRIM | SGX_SECINFO_MODIFIED;
        eaccept_op.ret = 0;
        eaccept_op.header.type = ENCL_OP_EACCEPT;

        EXPECT_EQ(ENCL_CALL(&eaccept_op, &self->run, true), 0);

        EXPECT_EEXIT(&self->run);
        EXPECT_EQ(self->run.exception_vector, 0);
        EXPECT_EQ(self->run.exception_error_code, 0);
        EXPECT_EQ(self->run.exception_addr, 0);
        EXPECT_EQ(eaccept_op.ret, 0);

        eaccept_op.epc_addr = (unsigned long)tcs;
        eaccept_op.ret = 0;

        EXPECT_EQ(ENCL_CALL(&eaccept_op, &self->run, true), 0);

        EXPECT_EEXIT(&self->run);
        EXPECT_EQ(self->run.exception_vector, 0);
        EXPECT_EQ(self->run.exception_error_code, 0);
        EXPECT_EQ(self->run.exception_addr, 0);
        EXPECT_EQ(eaccept_op.ret, 0);

        eaccept_op.epc_addr = (unsigned long)ssa;
        eaccept_op.ret = 0;

        EXPECT_EQ(ENCL_CALL(&eaccept_op, &self->run, true), 0);

        EXPECT_EEXIT(&self->run);
        EXPECT_EQ(self->run.exception_vector, 0);
        EXPECT_EQ(self->run.exception_error_code, 0);
        EXPECT_EQ(self->run.exception_addr, 0);
        EXPECT_EQ(eaccept_op.ret, 0);

        /* Send final ioctl() to complete page removal. */
        memset(&remove_ioc, 0, sizeof(remove_ioc));

        remove_ioc.offset = total_size;
        remove_ioc.length = 3 * PAGE_SIZE;

        ret = ioctl(self->encl.fd, SGX_IOC_ENCLAVE_REMOVE_PAGES, &remove_ioc);
        errno_save = ret == -1 ? errno : 0;

        EXPECT_EQ(ret, 0);
        EXPECT_EQ(errno_save, 0);
        EXPECT_EQ(remove_ioc.count, 3 * PAGE_SIZE);

        /*
         * Enter enclave via TCS #1 and access location where TCS #3 was to
         * trigger dynamic add of regular page at that location.
         */
        eaccept_op.epc_addr = (unsigned long)tcs;
        eaccept_op.flags = SGX_SECINFO_R | SGX_SECINFO_W | SGX_SECINFO_REG | SGX_SECINFO_PENDING;
        eaccept_op.ret = 0;
        eaccept_op.header.type = ENCL_OP_EACCEPT;

        EXPECT_EQ(ENCL_CALL(&eaccept_op, &self->run, true), 0);

        EXPECT_EEXIT(&self->run);
        EXPECT_EQ(self->run.exception_vector, 0);
        EXPECT_EQ(self->run.exception_error_code, 0);
        EXPECT_EQ(self->run.exception_addr, 0);
        EXPECT_EQ(eaccept_op.ret, 0);

        /*
         * New page should be accessible from within enclave - write to it.
         */
        put_addr_op.value = MAGIC;
        put_addr_op.addr = (unsigned long)tcs;
        put_addr_op.header.type = ENCL_OP_PUT_TO_ADDRESS;

        EXPECT_EQ(ENCL_CALL(&put_addr_op, &self->run, true), 0);

        EXPECT_EEXIT(&self->run);
        EXPECT_EQ(self->run.exception_vector, 0);
        EXPECT_EQ(self->run.exception_error_code, 0);
        EXPECT_EQ(self->run.exception_addr, 0);

        /*
         * Read memory from newly added page that was just written to,
         * confirming that data previously written (MAGIC) is present.
         */
        get_addr_op.value = 0;
        get_addr_op.addr = (unsigned long)tcs;
        get_addr_op.header.type = ENCL_OP_GET_FROM_ADDRESS;

        EXPECT_EQ(ENCL_CALL(&get_addr_op, &self->run, true), 0);

        EXPECT_EQ(get_addr_op.value, MAGIC);
        EXPECT_EEXIT(&self->run);
        EXPECT_EQ(self->run.exception_vector, 0);
        EXPECT_EQ(self->run.exception_error_code, 0);
        EXPECT_EQ(self->run.exception_addr, 0);

        munmap(addr, 3 * PAGE_SIZE);
}

/*
 * Ensure sane behavior if user requests page removal, does not run
 * EACCEPT from within enclave but still attempts to finalize page removal
 * with the SGX_IOC_ENCLAVE_REMOVE_PAGES ioctl(). The latter should fail
 * because the removal was not EACCEPTed from within the enclave.
 */
TEST_F(enclave, remove_added_page_no_eaccept)
{
        struct sgx_enclave_remove_pages remove_ioc;
        struct encl_op_get_from_addr get_addr_op;
        struct sgx_enclave_modify_types modt_ioc;
        struct encl_op_put_to_addr put_addr_op;
        unsigned long data_start;
        int ret, errno_save;

        ASSERT_TRUE(setup_test_encl(ENCL_HEAP_SIZE_DEFAULT, &self->encl, _metadata));

        memset(&self->run, 0, sizeof(self->run));
        self->run.tcs = self->encl.encl_base;

        /*
         * Hardware (SGX2) and kernel support is needed for this test. Start
         * with check that test has a chance of succeeding.
         */
        memset(&modt_ioc, 0, sizeof(modt_ioc));
        ret = ioctl(self->encl.fd, SGX_IOC_ENCLAVE_MODIFY_TYPES, &modt_ioc);

        if (ret == -1) {
                if (errno == ENOTTY)
                        SKIP(return,
                             "Kernel does not support SGX_IOC_ENCLAVE_MODIFY_TYPES ioctl()");
                else if (errno == ENODEV)
                        SKIP(return, "System does not support SGX2");
        }

        /*
         * Invalid parameters were provided during sanity check,
         * expect command to fail.
         */
        EXPECT_EQ(ret, -1);

        /*
         * Page that will be removed is the second data page in the .data
         * segment. This forms part of the local encl_buffer within the
         * enclave.
         */
        data_start = self->encl.encl_base +
                     encl_get_data_offset(&self->encl) + PAGE_SIZE;

        /*
         * Sanity check that page at @data_start is writable before
         * removing it.
         *
         * Start by writing MAGIC to test page.
         */
        put_addr_op.value = MAGIC;
        put_addr_op.addr = data_start;
        put_addr_op.header.type = ENCL_OP_PUT_TO_ADDRESS;

        EXPECT_EQ(ENCL_CALL(&put_addr_op, &self->run, true), 0);

        EXPECT_EEXIT(&self->run);
        EXPECT_EQ(self->run.exception_vector, 0);
        EXPECT_EQ(self->run.exception_error_code, 0);
        EXPECT_EQ(self->run.exception_addr, 0);

        /*
         * Read memory that was just written to, confirming that data
         * previously written (MAGIC) is present.
         */
        get_addr_op.value = 0;
        get_addr_op.addr = data_start;
        get_addr_op.header.type = ENCL_OP_GET_FROM_ADDRESS;

        EXPECT_EQ(ENCL_CALL(&get_addr_op, &self->run, true), 0);

        EXPECT_EQ(get_addr_op.value, MAGIC);
        EXPECT_EEXIT(&self->run);
        EXPECT_EQ(self->run.exception_vector, 0);
        EXPECT_EQ(self->run.exception_error_code, 0);
        EXPECT_EQ(self->run.exception_addr, 0);

        /* Start page removal by requesting change of page type to PT_TRIM */
        memset(&modt_ioc, 0, sizeof(modt_ioc));

        modt_ioc.offset = encl_get_data_offset(&self->encl) + PAGE_SIZE;
        modt_ioc.length = PAGE_SIZE;
        modt_ioc.page_type = SGX_PAGE_TYPE_TRIM;

        ret = ioctl(self->encl.fd, SGX_IOC_ENCLAVE_MODIFY_TYPES, &modt_ioc);
        errno_save = ret == -1 ? errno : 0;

        EXPECT_EQ(ret, 0);
        EXPECT_EQ(errno_save, 0);
        EXPECT_EQ(modt_ioc.result, 0);
        EXPECT_EQ(modt_ioc.count, 4096);

        /* Skip EACCEPT */

        /* Send final ioctl() to complete page removal */
        memset(&remove_ioc, 0, sizeof(remove_ioc));

        remove_ioc.offset = encl_get_data_offset(&self->encl) + PAGE_SIZE;
        remove_ioc.length = PAGE_SIZE;

        ret = ioctl(self->encl.fd, SGX_IOC_ENCLAVE_REMOVE_PAGES, &remove_ioc);
        errno_save = ret == -1 ? errno : 0;

        /* Operation not permitted since EACCEPT was omitted. */
        EXPECT_EQ(ret, -1);
        EXPECT_EQ(errno_save, EPERM);
        EXPECT_EQ(remove_ioc.count, 0);
}

/*
 * Request enclave page removal but instead of correctly following with
 * EACCEPT a read attempt to page is made from within the enclave.
 */
TEST_F(enclave, remove_added_page_invalid_access)
{
        struct encl_op_get_from_addr get_addr_op;
        struct encl_op_put_to_addr put_addr_op;
        struct sgx_enclave_modify_types ioc;
        unsigned long data_start;
        int ret, errno_save;

        ASSERT_TRUE(setup_test_encl(ENCL_HEAP_SIZE_DEFAULT, &self->encl, _metadata));

        memset(&self->run, 0, sizeof(self->run));
        self->run.tcs = self->encl.encl_base;

        /*
         * Hardware (SGX2) and kernel support is needed for this test. Start
         * with check that test has a chance of succeeding.
         */
        memset(&ioc, 0, sizeof(ioc));
        ret = ioctl(self->encl.fd, SGX_IOC_ENCLAVE_MODIFY_TYPES, &ioc);

        if (ret == -1) {
                if (errno == ENOTTY)
                        SKIP(return,
                             "Kernel does not support SGX_IOC_ENCLAVE_MODIFY_TYPES ioctl()");
                else if (errno == ENODEV)
                        SKIP(return, "System does not support SGX2");
        }

        /*
         * Invalid parameters were provided during sanity check,
         * expect command to fail.
         */
        EXPECT_EQ(ret, -1);

        /*
         * Page that will be removed is the second data page in the .data
         * segment. This forms part of the local encl_buffer within the
         * enclave.
         */
        data_start = self->encl.encl_base +
                     encl_get_data_offset(&self->encl) + PAGE_SIZE;

        /*
         * Sanity check that page at @data_start is writable before
         * removing it.
         *
         * Start by writing MAGIC to test page.
         */
        put_addr_op.value = MAGIC;
        put_addr_op.addr = data_start;
        put_addr_op.header.type = ENCL_OP_PUT_TO_ADDRESS;

        EXPECT_EQ(ENCL_CALL(&put_addr_op, &self->run, true), 0);

        EXPECT_EEXIT(&self->run);
        EXPECT_EQ(self->run.exception_vector, 0);
        EXPECT_EQ(self->run.exception_error_code, 0);
        EXPECT_EQ(self->run.exception_addr, 0);

        /*
         * Read memory that was just written to, confirming that data
         * previously written (MAGIC) is present.
         */
        get_addr_op.value = 0;
        get_addr_op.addr = data_start;
        get_addr_op.header.type = ENCL_OP_GET_FROM_ADDRESS;

        EXPECT_EQ(ENCL_CALL(&get_addr_op, &self->run, true), 0);

        EXPECT_EQ(get_addr_op.value, MAGIC);
        EXPECT_EEXIT(&self->run);
        EXPECT_EQ(self->run.exception_vector, 0);
        EXPECT_EQ(self->run.exception_error_code, 0);
        EXPECT_EQ(self->run.exception_addr, 0);

        /* Start page removal by requesting change of page type to PT_TRIM. */
        memset(&ioc, 0, sizeof(ioc));

        ioc.offset = encl_get_data_offset(&self->encl) + PAGE_SIZE;
        ioc.length = PAGE_SIZE;
        ioc.page_type = SGX_PAGE_TYPE_TRIM;

        ret = ioctl(self->encl.fd, SGX_IOC_ENCLAVE_MODIFY_TYPES, &ioc);
        errno_save = ret == -1 ? errno : 0;

        EXPECT_EQ(ret, 0);
        EXPECT_EQ(errno_save, 0);
        EXPECT_EQ(ioc.result, 0);
        EXPECT_EQ(ioc.count, 4096);

        /*
         * Read from page that was just removed.
         */
        get_addr_op.value = 0;

        EXPECT_EQ(ENCL_CALL(&get_addr_op, &self->run, true), 0);

        /*
         * From kernel perspective the page is present but according to SGX the
         * page should not be accessible so a #PF with SGX bit set is
         * expected.
         */

        EXPECT_EQ(self->run.function, ERESUME);
        EXPECT_EQ(self->run.exception_vector, 14);
        EXPECT_EQ(self->run.exception_error_code, 0x8005);
        EXPECT_EQ(self->run.exception_addr, data_start);
}

/*
 * Request enclave page removal and correctly follow with
 * EACCEPT but do not follow with removal ioctl() but instead a read attempt
 * to removed page is made from within the enclave.
 */
TEST_F(enclave, remove_added_page_invalid_access_after_eaccept)
{
        struct encl_op_get_from_addr get_addr_op;
        struct encl_op_put_to_addr put_addr_op;
        struct sgx_enclave_modify_types ioc;
        struct encl_op_eaccept eaccept_op;
        unsigned long data_start;
        int ret, errno_save;

        ASSERT_TRUE(setup_test_encl(ENCL_HEAP_SIZE_DEFAULT, &self->encl, _metadata));

        memset(&self->run, 0, sizeof(self->run));
        self->run.tcs = self->encl.encl_base;

        /*
         * Hardware (SGX2) and kernel support is needed for this test. Start
         * with check that test has a chance of succeeding.
         */
        memset(&ioc, 0, sizeof(ioc));
        ret = ioctl(self->encl.fd, SGX_IOC_ENCLAVE_MODIFY_TYPES, &ioc);

        if (ret == -1) {
                if (errno == ENOTTY)
                        SKIP(return,
                             "Kernel does not support SGX_IOC_ENCLAVE_MODIFY_TYPES ioctl()");
                else if (errno == ENODEV)
                        SKIP(return, "System does not support SGX2");
        }

        /*
         * Invalid parameters were provided during sanity check,
         * expect command to fail.
         */
        EXPECT_EQ(ret, -1);

        /*
         * Page that will be removed is the second data page in the .data
         * segment. This forms part of the local encl_buffer within the
         * enclave.
         */
        data_start = self->encl.encl_base +
                     encl_get_data_offset(&self->encl) + PAGE_SIZE;

        /*
         * Sanity check that page at @data_start is writable before
         * removing it.
         *
         * Start by writing MAGIC to test page.
         */
        put_addr_op.value = MAGIC;
        put_addr_op.addr = data_start;
        put_addr_op.header.type = ENCL_OP_PUT_TO_ADDRESS;

        EXPECT_EQ(ENCL_CALL(&put_addr_op, &self->run, true), 0);

        EXPECT_EEXIT(&self->run);
        EXPECT_EQ(self->run.exception_vector, 0);
        EXPECT_EQ(self->run.exception_error_code, 0);
        EXPECT_EQ(self->run.exception_addr, 0);

        /*
         * Read memory that was just written to, confirming that data
         * previously written (MAGIC) is present.
         */
        get_addr_op.value = 0;
        get_addr_op.addr = data_start;
        get_addr_op.header.type = ENCL_OP_GET_FROM_ADDRESS;

        EXPECT_EQ(ENCL_CALL(&get_addr_op, &self->run, true), 0);

        EXPECT_EQ(get_addr_op.value, MAGIC);
        EXPECT_EEXIT(&self->run);
        EXPECT_EQ(self->run.exception_vector, 0);
        EXPECT_EQ(self->run.exception_error_code, 0);
        EXPECT_EQ(self->run.exception_addr, 0);

        /* Start page removal by requesting change of page type to PT_TRIM. */
        memset(&ioc, 0, sizeof(ioc));

        ioc.offset = encl_get_data_offset(&self->encl) + PAGE_SIZE;
        ioc.length = PAGE_SIZE;
        ioc.page_type = SGX_PAGE_TYPE_TRIM;

        ret = ioctl(self->encl.fd, SGX_IOC_ENCLAVE_MODIFY_TYPES, &ioc);
        errno_save = ret == -1 ? errno : 0;

        EXPECT_EQ(ret, 0);
        EXPECT_EQ(errno_save, 0);
        EXPECT_EQ(ioc.result, 0);
        EXPECT_EQ(ioc.count, 4096);

        eaccept_op.epc_addr = (unsigned long)data_start;
        eaccept_op.ret = 0;
        eaccept_op.flags = SGX_SECINFO_TRIM | SGX_SECINFO_MODIFIED;
        eaccept_op.header.type = ENCL_OP_EACCEPT;

        EXPECT_EQ(ENCL_CALL(&eaccept_op, &self->run, true), 0);

        EXPECT_EEXIT(&self->run);
        EXPECT_EQ(self->run.exception_vector, 0);
        EXPECT_EQ(self->run.exception_error_code, 0);
        EXPECT_EQ(self->run.exception_addr, 0);
        EXPECT_EQ(eaccept_op.ret, 0);

        /* Skip ioctl() to remove page. */

        /*
         * Read from page that was just removed.
         */
        get_addr_op.value = 0;

        EXPECT_EQ(ENCL_CALL(&get_addr_op, &self->run, true), 0);

        /*
         * From kernel perspective the page is present but according to SGX the
         * page should not be accessible so a #PF with SGX bit set is
         * expected.
         */

        EXPECT_EQ(self->run.function, ERESUME);
        EXPECT_EQ(self->run.exception_vector, 14);
        EXPECT_EQ(self->run.exception_error_code, 0x8005);
        EXPECT_EQ(self->run.exception_addr, data_start);
}

TEST_F(enclave, remove_untouched_page)
{
        struct sgx_enclave_remove_pages remove_ioc;
        struct sgx_enclave_modify_types modt_ioc;
        struct encl_op_eaccept eaccept_op;
        unsigned long data_start;
        int ret, errno_save;

        ASSERT_TRUE(setup_test_encl(ENCL_HEAP_SIZE_DEFAULT, &self->encl, _metadata));

        /*
         * Hardware (SGX2) and kernel support is needed for this test. Start
         * with check that test has a chance of succeeding.
         */
        memset(&modt_ioc, 0, sizeof(modt_ioc));
        ret = ioctl(self->encl.fd, SGX_IOC_ENCLAVE_MODIFY_TYPES, &modt_ioc);

        if (ret == -1) {
                if (errno == ENOTTY)
                        SKIP(return,
                             "Kernel does not support SGX_IOC_ENCLAVE_MODIFY_TYPES ioctl()");
                else if (errno == ENODEV)
                        SKIP(return, "System does not support SGX2");
        }

        /*
         * Invalid parameters were provided during sanity check,
         * expect command to fail.
         */
        EXPECT_EQ(ret, -1);

        /* SGX2 is supported by kernel and hardware, test can proceed. */
        memset(&self->run, 0, sizeof(self->run));
        self->run.tcs = self->encl.encl_base;

        data_start = self->encl.encl_base +
                         encl_get_data_offset(&self->encl) + PAGE_SIZE;

        memset(&modt_ioc, 0, sizeof(modt_ioc));

        modt_ioc.offset = encl_get_data_offset(&self->encl) + PAGE_SIZE;
        modt_ioc.length = PAGE_SIZE;
        modt_ioc.page_type = SGX_PAGE_TYPE_TRIM;
        ret = ioctl(self->encl.fd, SGX_IOC_ENCLAVE_MODIFY_TYPES, &modt_ioc);
        errno_save = ret == -1 ? errno : 0;

        EXPECT_EQ(ret, 0);
        EXPECT_EQ(errno_save, 0);
        EXPECT_EQ(modt_ioc.result, 0);
        EXPECT_EQ(modt_ioc.count, 4096);

        /*
         * Enter enclave via TCS #1 and approve page removal by sending
         * EACCEPT for removed page.
         */

        eaccept_op.epc_addr = data_start;
        eaccept_op.flags = SGX_SECINFO_TRIM | SGX_SECINFO_MODIFIED;
        eaccept_op.ret = 0;
        eaccept_op.header.type = ENCL_OP_EACCEPT;

        EXPECT_EQ(ENCL_CALL(&eaccept_op, &self->run, true), 0);
        EXPECT_EEXIT(&self->run);
        EXPECT_EQ(self->run.exception_vector, 0);
        EXPECT_EQ(self->run.exception_error_code, 0);
        EXPECT_EQ(self->run.exception_addr, 0);
        EXPECT_EQ(eaccept_op.ret, 0);

        memset(&remove_ioc, 0, sizeof(remove_ioc));

        remove_ioc.offset = encl_get_data_offset(&self->encl) + PAGE_SIZE;
        remove_ioc.length = PAGE_SIZE;
        ret = ioctl(self->encl.fd, SGX_IOC_ENCLAVE_REMOVE_PAGES, &remove_ioc);
        errno_save = ret == -1 ? errno : 0;

        EXPECT_EQ(ret, 0);
        EXPECT_EQ(errno_save, 0);
        EXPECT_EQ(remove_ioc.count, 4096);
}

TEST_HARNESS_MAIN