/*
 * Copyright (C) 2011-2017 Intel Corporation. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 *   * Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 *   * Redistributions in binary form must reproduce the above copyright
 *     notice, this list of conditions and the following disclaimer in
 *     the documentation and/or other materials provided with the
 *     distribution.
 *   * Neither the name of Intel Corporation nor the names of its
 *     contributors may be used to endorse or promote products derived
 *     from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 */


#include "enclave_creator_hw.h"
#include "se_trace.h"
#include "se_page_attr.h"
#include "isgx_user.h"
#include "sig_handler.h"
#include "se_error_internal.h"
#include "se_memcpy.h"
#include "se_atomic.h"
#include "se_detect.h"
#include "cpuid.h"
#include <assert.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <sys/ioctl.h>
#include <errno.h>
#include <sys/mman.h>
#include <stdlib.h>


static EnclaveCreatorHW g_enclave_creator_hw;

EnclaveCreator* g_enclave_creator = &g_enclave_creator_hw;
static uint64_t g_eid = 0x1;


EnclaveCreatorHW::EnclaveCreatorHW():
    m_hdevice(-1),
    m_sig_registered(false)
{
    se_mutex_init(&m_sig_mutex);
}

EnclaveCreatorHW::~EnclaveCreatorHW()
{
    close_se_device();
}

int EnclaveCreatorHW::error_driver2urts(int driver_error)
{
    int ret = SGX_ERROR_UNEXPECTED;

    switch(driver_error)
    {
#if 0
    case SGX_ERROR:
        if(ENOMEM == errno)
            ret = SGX_ERROR_OUT_OF_MEMORY;
        else
            ret = SGX_ERROR_NO_DEVICE;
        break;
#endif
    case SGX_INVALID_ATTRIBUTE:
        ret = SGX_ERROR_INVALID_ATTRIBUTE;
        break;
    case SGX_INVALID_MEASUREMENT:
        ret = SE_ERROR_INVALID_MEASUREMENT;
        break;
    case SGX_INVALID_SIG_STRUCT:
    case SGX_INVALID_SIGNATURE:
        ret = SGX_ERROR_INVALID_SIGNATURE;
        break;
    case SGX_INVALID_CPUSVN:
        ret = SGX_ERROR_INVALID_CPUSVN;
        break;
    case SGX_INVALID_ISVSVN:
        ret = SGX_ERROR_INVALID_ISVSVN;
        break;
    case SGX_UNMASKED_EVENT:
        ret = SGX_ERROR_DEVICE_BUSY;
        break;
    case (int)SGX_POWER_LOST_ENCLAVE: // [-Wc++11-narrowing]
        ret = SGX_ERROR_ENCLAVE_LOST;
        break;
    default:
        SE_TRACE(SE_TRACE_WARNING, "unexpected error %#x from driver, should be uRTS/driver bug\n", driver_error);
        ret = SGX_ERROR_UNEXPECTED;
        break;
    }

    return ret;
}

int EnclaveCreatorHW::create_enclave(secs_t *secs, sgx_enclave_id_t *enclave_id, void **start_addr, bool ae)
{
    assert(secs != NULL && enclave_id != NULL && start_addr != NULL);
    UNUSED(ae);
    int ret = 0;

    if (false == open_se_device())
        return SGX_ERROR_NO_DEVICE;

    SE_TRACE(SE_TRACE_DEBUG, "\n secs.attibutes.flags = %llx, secs.attributes.xfrm = %llx \n"
             , secs->attributes.flags, secs->attributes.xfrm);

    //SECS:BASEADDR must be naturally aligned on an SECS.SIZE boundary
    //This alignment is guaranteed by driver, at linux-sgx-driver/sgx_main.c:141 to 146
    //141     addr = current->mm->get_unmapped_area(file, addr, 2 * len, pgoff,
    //142                           flags);
    //143     if (IS_ERR_VALUE(addr))
    //144         return addr;
    //145
    //146     addr = (addr + (len - 1)) & ~(len - 1);
    //147
    //148     return addr;
    //Thus the only thing to do is to let the kernel driver align the memory.
    void* enclave_base = mmap(NULL, (size_t)secs->size, PROT_READ | PROT_WRITE | PROT_EXEC, MAP_SHARED, m_hdevice, 0);
    if(enclave_base == MAP_FAILED)
    {
        SE_TRACE(SE_TRACE_WARNING, "\nISGX_IOCTL_ENCLAVE_CREATE failed: mmap failed, errno = %d\n", errno);
        return SGX_ERROR_OUT_OF_MEMORY;
    }
    secs->base = (void*)enclave_base;
    
    struct sgx_enclave_create param = {0};
    param.src = (uintptr_t)(secs);
    ret = ioctl(m_hdevice, SGX_IOC_ENCLAVE_CREATE, &param);
    if(ret) {
        SE_TRACE(SE_TRACE_WARNING, "\nISGX_IOCTL_ENCLAVE_CREATE failed: errno = %d\n", errno);
        return error_driver2urts(ret);
    }
    *enclave_id = se_atomic_inc64(&g_eid);
    *start_addr = secs->base;

    return SGX_SUCCESS;
}


int EnclaveCreatorHW::add_enclave_page(sgx_enclave_id_t enclave_id, void *src, uint64_t rva, const sec_info_t &sinfo, uint32_t attr)
{
    assert((rva & ((1<<SE_PAGE_SHIFT)-1)) == 0);
    void* source = src;
    uint8_t color_page[SE_PAGE_SIZE] = { 0 };
    if(NULL == source)
    {
        memset(color_page, 0, SE_PAGE_SIZE);
        source = reinterpret_cast<void*>(&color_page);
    }

    int ret = 0;
    struct sgx_enclave_add_page addp = { 0, 0, 0, 0 };

    addp.addr = (__u64)enclave_id + (__u64)rva;
    addp.src = reinterpret_cast<uintptr_t>(source);
    addp.secinfo = reinterpret_cast<uintptr_t>(const_cast<sec_info_t *>(&sinfo));
    if(((1<<DoEEXTEND) & attr))
        addp.mrmask |= 0xFFFF;
    
    ret = ioctl(m_hdevice, SGX_IOC_ENCLAVE_ADD_PAGE, &addp);
    if(ret) {
        SE_TRACE(SE_TRACE_WARNING, "\nAdd Page - %p to %p... FAIL\n", source, rva);
        return error_driver2urts(ret);
    }
   
    return SGX_SUCCESS;
}

int EnclaveCreatorHW::try_init_enclave(sgx_enclave_id_t enclave_id, enclave_css_t *enclave_css, token_t *launch)
{
    int ret = 0;
    struct sgx_enclave_init initp = { 0, 0, 0 };
    initp.addr = (__u64)enclave_id;
    initp.sigstruct = reinterpret_cast<uintptr_t>(enclave_css);
    //launch should NOT be NULL, because it has been checked in urts_com.h::_create_enclave(...)
    assert(launch != NULL);

    initp.einittoken = reinterpret_cast<uintptr_t>(launch);
    ret = ioctl(m_hdevice, SGX_IOC_ENCLAVE_INIT, &initp);
    if (ret) {
        SE_TRACE(SE_TRACE_WARNING, "\nISGX_IOCTL_ENCLAVE_INIT failed error = %d\n", ret);
        return error_driver2urts(ret);
    }

    //register signal handler
    se_mutex_lock(&m_sig_mutex);
    if(false == m_sig_registered)
    {
        reg_sig_handler();
        m_sig_registered = true;
    }
    se_mutex_unlock(&m_sig_mutex);

    return SGX_SUCCESS;
}

//for linux hw mode, enclave_id is actually start address here
int EnclaveCreatorHW::destroy_enclave(sgx_enclave_id_t enclave_id, uint64_t enclave_size)
{
    int ret = 0;

    ret = munmap((void*)enclave_id, (size_t)enclave_size);

    if (0 != ret) {
        SE_TRACE(SE_TRACE_WARNING, "destroy SGX enclave failed, error = %d\n", errno);
        ret = SGX_ERROR_UNEXPECTED;
    }
    else
    {
        ret = SGX_SUCCESS;
    }

    return ret;
}

bool EnclaveCreatorHW::get_plat_cap(sgx_misc_attribute_t *misc_attr)
{
    return get_plat_cap_by_cpuid(misc_attr);
}



bool EnclaveCreatorHW::open_se_device()
{
    LockGuard lock(&m_dev_mutex);
    int fd = -1;

    if(-1 != m_hdevice)
    {
        return true;
    }

    fd = open("/dev/isgx", O_RDWR);
    if (-1 == fd) {
        SE_TRACE(SE_TRACE_WARNING, "open isgx device failed\n");
        return false;
    }
    m_hdevice = fd;

    return true;
}

void EnclaveCreatorHW::close_se_device()
{
    LockGuard lock(&m_dev_mutex);

    if (m_hdevice != -1)
    {
        close(m_hdevice);
        m_hdevice = -1;
    }
}