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sangfansh/App.cpp

Last active Jul 11, 2018
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#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"
/* Global EID shared by multiple threads */
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 code is 0x%X. Please refer to the \"Intel SGX SDK Developer Reference\" for more details.\n", ret);
}
/* Initialize the enclave:
* Step 1: try to retrieve the launch token saved by last transaction
* Step 2: call sgx_create_enclave to initialize an enclave instance
* Step 3: save the launch token if it is updated
*/
int initialize_enclave(void)
{
char token_path[MAX_PATH] = {'\0'};
sgx_launch_token_t token = {0};
sgx_status_t ret = SGX_ERROR_UNEXPECTED;
int updated = 0;
/* Step 1: try to retrieve the launch token saved by last transaction
* if there is no token, then create a new one.
*/
/* try to get the token saved in $HOME */
const char *home_dir = getpwuid(getuid())->pw_dir;
if (home_dir != NULL &&
(strlen(home_dir)+strlen("/")+sizeof(TOKEN_FILENAME)+1) <= MAX_PATH) {
/* compose the token path */
strncpy(token_path, home_dir, strlen(home_dir));
strncat(token_path, "/", strlen("/"));
strncat(token_path, TOKEN_FILENAME, sizeof(TOKEN_FILENAME)+1);
} else {
/* if token path is too long or $HOME is NULL */
strncpy(token_path, TOKEN_FILENAME, sizeof(TOKEN_FILENAME));
}
FILE *fp = fopen(token_path, "rb");
if (fp == NULL && (fp = fopen(token_path, "wb")) == NULL) {
printf("Warning: Failed to create/open the launch token file \"%s\".\n", token_path);
}
if (fp != NULL) {
/* read the token from saved file */
size_t read_num = fread(token, 1, sizeof(sgx_launch_token_t), fp);
if (read_num != 0 && read_num != sizeof(sgx_launch_token_t)) {
/* if token is invalid, clear the buffer */
memset(&token, 0x0, sizeof(sgx_launch_token_t));
printf("Warning: Invalid launch token read from \"%s\".\n", token_path);
}
}
/* Step 2: 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);
if (fp != NULL) fclose(fp);
return -1;
}
/* Step 3: save the launch token if it is updated */
if (updated == FALSE || fp == NULL) {
/* if the token is not updated, or file handler is invalid, do not perform saving */
if (fp != NULL) fclose(fp);
return 0;
}
/* reopen the file with write capablity */
fp = freopen(token_path, "wb", fp);
if (fp == NULL) return 0;
size_t write_num = fwrite(token, 1, sizeof(sgx_launch_token_t), fp);
if (write_num != sizeof(sgx_launch_token_t))
printf("Warning: Failed to save launch token to \"%s\".\n", token_path);
fclose(fp);
return 0;
}
/* OCall functions */
void ocall_print_string(const char *str)
{
/* Proxy/Bridge will check the length and null-terminate
* the input string to prevent buffer overflow.
*/
printf("%s", str);
}
/* 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;
}
printf_helloworld(global_eid);
/* Destroy the enclave */
sgx_destroy_enclave(global_eid);
return 0;
}
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