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Key System Functionality Supplements

This framework provides some system functions that Intel SGX does not provide.

High-precision Time Support​

We support obtaining three time precisions: seconds, microseconds, and nanoseconds.

time_t now_seconds = DateTime::Now().GetTimestamp();
int64_t now_milliseconds = PreciseTime::NowInMilliseconds();
int64_t now_nanoseconds = PreciseTime::NowInNanoseconds();
warning

This timestamp is obtained from an untrusted zone and is therefore unreliable.

Secure Untrusted Memory Operations​

When we perform untrusted memory operations, such as allocating untrusted memory, copying trusted memory to untrusted memory, and releasing untrusted memory, we will perform a check on the untrusted memory.

const char* src = "Test data";
size_t len = strlen(src) + 1;
char* dest = static_cast<char*>(malloc_outside(len));
memcpy_to_outside(dest, src, len);
free_outside(dest, len);
warning

All operations related to untrusted memory require attention to safety, and the interface we provide will check the memory to ensure operation safety.

File System Access Support​

We support functions such as obtaining file size, type and permissions, creating directories, deleting files, reading and writing files, etc.

Path test_file("/root");
test_file /= Path("test_file");
std::string test_data = "Hello world!";

const std::vector<uint8_t> test_data = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15};
PlainFileWriter writer(test_file.String());
writer.WriteAllBytes(test_data);

const FileStatus fs = status(test_file);
if (!exists(fs) || !is_regular_file(fs)) {
    Remove(test_file);
    return false;
}

PlainFileReader reader(test_file.String());
std::string file_data = reader.ReadAllBytes();
if (file_data != test_data) {
    Remove(test_file);
    return false;
}