// Licensed to the Apache Software Foundation (ASF) under one
// or more contributor license agreements.  See the NOTICE file
// distributed with this work for additional information
// regarding copyright ownership.  The ASF licenses this file
// to you under the Apache License, Version 2.0 (the
// "License"); you may not use this file except in compliance
// with the License.  You may obtain a copy of the License at
//
//   http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing,
// software distributed under the License is distributed on an
// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
// KIND, either express or implied.  See the License for the
// specific language governing permissions and limitations
// under the License..

#include <stdio.h>
#include <string.h>
#include <assert.h>

#include <unistd.h>
#include <pwd.h>
#define MAX_PATH FILENAME_MAX

#include "sgx_urts.h"
#include "app.h"
#include "Enclave_u.h"


int sha_256();
int aes_gcm_128();
int aes_cmac();
int rsa();

sgx_enclave_id_t global_eid = 0;

typedef struct _sgx_errlist_t {
    sgx_status_t err;
    const char *msg;
    const char *sug; /* Suggestion */
} sgx_errlist_t;

/* Error code returned by sgx_create_enclave */
static sgx_errlist_t sgx_errlist[] = {
    {
        SGX_ERROR_UNEXPECTED,
        "Unexpected error occurred.",
        NULL
    },
    {
        SGX_ERROR_INVALID_PARAMETER,
        "Invalid parameter.",
        NULL
    },
    {
        SGX_ERROR_OUT_OF_MEMORY,
        "Out of memory.",
        NULL
    },
    {
        SGX_ERROR_ENCLAVE_LOST,
        "Power transition occurred.",
        "Please refer to the sample \"PowerTransition\" for details."
    },
    {
        SGX_ERROR_INVALID_ENCLAVE,
        "Invalid enclave image.",
        NULL
    },
    {
        SGX_ERROR_INVALID_ENCLAVE_ID,
        "Invalid enclave identification.",
        NULL
    },
    {
        SGX_ERROR_INVALID_SIGNATURE,
        "Invalid enclave signature.",
        NULL
    },
    {
        SGX_ERROR_OUT_OF_EPC,
        "Out of EPC memory.",
        NULL
    },
    {
        SGX_ERROR_NO_DEVICE,
        "Invalid SGX device.",
        "Please make sure SGX module is enabled in the BIOS, and install SGX driver afterwards."
    },
    {
        SGX_ERROR_MEMORY_MAP_CONFLICT,
        "Memory map conflicted.",
        NULL
    },
    {
        SGX_ERROR_INVALID_METADATA,
        "Invalid enclave metadata.",
        NULL
    },
    {
        SGX_ERROR_DEVICE_BUSY,
        "SGX device was busy.",
        NULL
    },
    {
        SGX_ERROR_INVALID_VERSION,
        "Enclave version was invalid.",
        NULL
    },
    {
        SGX_ERROR_INVALID_ATTRIBUTE,
        "Enclave was not authorized.",
        NULL
    },
    {
        SGX_ERROR_ENCLAVE_FILE_ACCESS,
        "Can't open enclave file.",
        NULL
    },
};

/* Check error conditions for loading enclave */
void print_error_message(sgx_status_t ret)
{
    size_t idx = 0;
    size_t ttl = sizeof sgx_errlist/sizeof sgx_errlist[0];

    for (idx = 0; idx < ttl; idx++) {
        if(ret == sgx_errlist[idx].err) {
            if(NULL != sgx_errlist[idx].sug)
                printf("Info: %s\n", sgx_errlist[idx].sug);
            printf("Error: %s\n", sgx_errlist[idx].msg);
            break;
        }
    }

    if (idx == ttl)
        printf("Error: Unexpected error occurred.\n");
}

int initialize_enclave(void)
{
    sgx_launch_token_t token = {0};
    sgx_status_t ret = SGX_ERROR_UNEXPECTED;
    int updated = 0;

    /* call sgx_create_enclave to initialize an enclave instance */
    /* Debug Support: set 2nd parameter to 1 */
    ret = sgx_create_enclave(ENCLAVE_FILENAME, SGX_DEBUG_FLAG, &token, &updated, &global_eid, NULL);
    if (ret != SGX_SUCCESS) {
        print_error_message(ret);
        return -1;
    }
    printf("[+] global_eid: %ld\n", global_eid);
    return 0;
}

/* Application entry */
int SGX_CDECL main(int argc, char *argv[])
{

    (void)(argc);
    (void)(argv);

    /* Initialize the enclave */
    if(initialize_enclave() < 0){
        printf("Enter a character before exit ...\n");
        getchar();
        return -1;
    }

    if( sha_256()==-1){ return -1;};

    if(aes_gcm_128()==-1){return -1;};

    if(aes_cmac()==-1){return -1;}

    if(rsa()==-1){return -1;}

    /* Destroy the enclave */
    sgx_destroy_enclave(global_eid);

    return 0;
}

int sha_256(){
    // SHA-256 test case comes from
    // https://tools.ietf.org/html/rfc4634
    // TEST1

    const char* str = "abc";
    size_t len = strlen(str);
    uint8_t * output_hash = (uint8_t *) malloc (32 + 1);

    sgx_status_t enclave_ret = SGX_SUCCESS;
    sgx_status_t sgx_ret = SGX_SUCCESS;

    printf("[+] sha256 input string is %s\n", str);
    printf("[+] Expected SHA256 hash: %s\n",
           "ba7816bf8f01cfea414140de5dae2223b00361a396177a9cb410ff61f20015ad");

    sgx_ret = calc_sha256(global_eid,
                         &enclave_ret,
                         (const uint8_t *) str,
                         len,
                         output_hash);

    if(sgx_ret != SGX_SUCCESS) {
        print_error_message(sgx_ret);
        return -1;
    }

    if(enclave_ret != SGX_SUCCESS) {
        print_error_message(enclave_ret);
        return -1;
    }

    printf("[+] SHA256 result is ");

    int i;
    for(i = 0; i < 32; i ++) {
        printf("%02x", output_hash[i]);
    }
    printf("\n");
    printf("[+] calc_sha256 success ...\n");
    return 0;
}

int aes_gcm_128(){
    // AES-GCM-128 test case comes from
    // http://csrc.nist.gov/groups/ST/toolkit/BCM/documents/proposedmodes/gcm/gcm-revised-spec.pdf
    // Test case 2

    printf("[+] Starting aes-gcm-128 encrypt calculation\n");
    uint8_t aes_gcm_plaintext[16] = {0};
    uint8_t aes_gcm_key[16] = {0};
    uint8_t aes_gcm_iv[12] = {0};
    uint8_t aes_gcm_ciphertext[16] = {0};

    uint8_t aes_gcm_mac[16] = {0};
    sgx_status_t enclave_ret = SGX_SUCCESS;
    sgx_status_t sgx_ret = SGX_SUCCESS;

    printf("[+] aes-gcm-128 args prepared!\n");
    printf("[+] aes-gcm-128 expected ciphertext: %s\n",
           "0388dace60b6a392f328c2b971b2fe78");
    sgx_ret = aes_gcm_128_encrypt(global_eid,
                                  &enclave_ret,
                                  aes_gcm_key,
                                  aes_gcm_plaintext,
                                  16,
                                  aes_gcm_iv,
                                  aes_gcm_ciphertext,
                                  aes_gcm_mac);

    printf("[+] aes-gcm-128 returned from enclave!\n");

    if(sgx_ret != SGX_SUCCESS) {
        print_error_message(sgx_ret);
        return -1;
    }

    if(enclave_ret != SGX_SUCCESS) {
        print_error_message(enclave_ret);
        return -1;
    }

    printf("[+] aes-gcm-128 ciphertext is: ");
    int i;
    for(i = 0; i < 16; i ++) {
        printf("%02x", aes_gcm_ciphertext[i]);
    }
    printf("\n");

    printf("[+] aes-gcm-128 result mac is: ");
    for(i = 0; i < 16; i ++) {
        printf("%02x", aes_gcm_mac[i]);
    }
    printf("\n");

    printf("[+] Starting aes-gcm-128 decrypt calculation\n");
    printf("[+] aes-gcm-128 expected plaintext:");
    for(i = 0; i < 16; i ++) {
        printf("%02x", aes_gcm_plaintext[i]);
    }
    printf("\n");

    uint8_t aes_gcm_decrypted_text[16] = {0};
    sgx_ret = aes_gcm_128_decrypt(global_eid,
                                  &enclave_ret,
                                  aes_gcm_key,
                                  aes_gcm_ciphertext,
                                  16,
                                  aes_gcm_iv,
                                  aes_gcm_mac,
                                  aes_gcm_decrypted_text);

    if(sgx_ret != SGX_SUCCESS) {
        print_error_message(sgx_ret);
        return -1;
    }
    if(enclave_ret != SGX_SUCCESS) {
        print_error_message(enclave_ret);
        return -1;
    }

    printf("[+] aes-gcm-128 decrypted plaintext is: ");
    for(i = 0; i < 16; i ++) {
        printf("%02x", aes_gcm_decrypted_text[i]);
    }
    printf("\n");

    printf("[+] aes-gcm-128 decrypt complete \n");
    return 0;
}


int aes_cmac(){
    // AES-CMAC test case comes from
    // https://tools.ietf.org/html/rfc4493
    // Example 3

    printf("[+] Starting aes-cmac test \n");
    printf("[+] aes-cmac expected digest: %s\n",
           "51f0bebf7e3b9d92fc49741779363cfe");

    sgx_status_t enclave_ret = SGX_SUCCESS;
    sgx_status_t sgx_ret = SGX_SUCCESS;

    uint8_t cmac_key[] = {
		0x2b, 0x7e, 0x15, 0x16, 0x28, 0xae, 0xd2, 0xa6,
        0xab, 0xf7, 0x15, 0x88, 0x09, 0xcf, 0x4f, 0x3c
	};

	uint8_t cmac_msg[] = {
        0x6b, 0xc1, 0xbe, 0xe2, 0x2e, 0x40, 0x9f, 0x96,
        0xe9, 0x3d, 0x7e, 0x11, 0x73, 0x93, 0x17, 0x2a,
        0xae, 0x2d, 0x8a, 0x57, 0x1e, 0x03, 0xac, 0x9c,
        0x9e, 0xb7, 0x6f, 0xac, 0x45, 0xaf, 0x8e, 0x51,
        0x30, 0xc8, 0x1c, 0x46, 0xa3, 0x5c, 0xe4, 0x11,
        0xe5, 0xfb, 0xc1, 0x19, 0x1a, 0x0a, 0x52, 0xef,
        0xf6, 0x9f, 0x24, 0x45, 0xdf, 0x4f, 0x9b, 0x17,
        0xad, 0x2b, 0x41, 0x7b, 0xe6, 0x6c, 0x37, 0x10
    };

    uint8_t cmac_result[16] = {0};

    sgx_ret = aes_cmac(global_eid,
                       &enclave_ret,
                       cmac_msg,
                       sizeof(cmac_msg),
                       cmac_key,
                       cmac_result);

    if(sgx_ret != SGX_SUCCESS) {
        print_error_message(sgx_ret);
        return -1;
    }
    if(enclave_ret != SGX_SUCCESS) {
        print_error_message(enclave_ret);
        return -1;
    }

    printf("[+] aes-cmac result is: ");
    int i;
    for(i = 0; i < 16; i ++){
        printf("%02x", cmac_result[i]);
    }
    printf("\n");
    return 0;
}

int rsa(){
    sgx_status_t enclave_ret = SGX_SUCCESS;
    sgx_status_t sgx_ret = SGX_SUCCESS;

    uint8_t rsa_msg[] = {
        0x6b, 0xc1, 0xbe, 0xe2, 0x2e, 0x40, 0x9f, 0x96,
        0xe9, 0x3d, 0x7e, 0x11, 0x73, 0x93, 0x17, 0x2a,
        0xae, 0x2d, 0x8a, 0x57, 0x1e, 0x03, 0xac, 0x9c,
        0x9e, 0xb7, 0x6f, 0xac, 0x45, 0xaf, 0x8e, 0x51,
        0x30, 0xc8, 0x1c, 0x46, 0xa3, 0x5c, 0xe4, 0x11,
        0xe5, 0xfb, 0xc1, 0x19, 0x1a, 0x0a, 0x52, 0xef,
        0xf6, 0x9f, 0x24, 0x45, 0xdf, 0x4f, 0x9b, 0x17,
        0xad, 0x2b, 0x41, 0x7b, 0xe6, 0x6c, 0x37, 0x10,
        0x6b, 0xc1, 0xbe, 0xe2, 0x2e, 0x40, 0x9f, 0x96,
        0xe9, 0x3d, 0x7e, 0x11, 0x73, 0x93, 0x17, 0x2a,
        0xae, 0x2d, 0x8a, 0x57, 0x1e, 0x03, 0xac, 0x9c,
        0x9e, 0xb7, 0x6f, 0xac, 0x45, 0xaf, 0x8e, 0x51,
        0x30, 0xc8, 0x1c, 0x46, 0xa3, 0x5c, 0xe4, 0x11,
        0xe5, 0xfb, 0xc1, 0x19, 0x1a, 0x0a, 0x52, 0xef,
        0xf6, 0x9f, 0x24, 0x45, 0xdf, 0x4f, 0x9b, 0x17,
        0xad, 0x2b, 0x41, 0x7b, 0xe6, 0x6c, 0x37, 0x10
    };

    sgx_ret = rsa_key(global_eid,
                      &enclave_ret,
                      rsa_msg,
                      sizeof(rsa_msg));

    if(sgx_ret != SGX_SUCCESS) {
        print_error_message(sgx_ret);
        return -1;
    }
    if(enclave_ret != SGX_SUCCESS) {
        print_error_message(enclave_ret);
        return -1;
    }
    printf("rsa_key success. \n");
    return 0;
}