how to: check features

by modifying cmake build options, different algorithms and features can be added to (or trimmed) from the library.

to list all available features (included in build):

using namespace mbedcrypto;

auto hashes = installed_hashes(); // returns std::vector<mbedcrypto::hasht_t>
std::cout << "supports " << hashes.size() << " hash algorithms: ";
for ( auto h : hashes ) { // print all installed hashes
    // convert type to string
    std::cout << to_string(h) << " , ";
}

// similarly
auto paddings = installed_paddings();
auto bmodes   = installed_block_modes();
auto ciphers  = installed_ciphers();
auto pks      = installed_pks();
auto curves   = installed_curves();

mbedcrypto types are enum classes and are also accessible from string names:

// convert from string to a type
auto htype = from_string<hash_t>("sha256");
if ( htype != hash_t::none ) {
}

to check for availability of a feature:

// check by type (enum class)
if ( supports(cipher_t::aes_256_cbc)   &&   supports(pk_t::rsa) ) {
    // do stuff
}
// check by algorithm name
if ( supports_hash("sha1")    &&    supports_pk("rsa") ) {
    // sign a message ...
}
// both upper and lower case are supported
if ( supports_cipher("CAMELLIA_128_CBC") ) {
}

// to check a single feature
if ( suppurts(features::aes_ni) ) {
    std::cout << "this system supports AESNI (hardware accelerated AES)"
              << std::endl;
}

if ( supports(features::aead)    &&    supports(cipher_bm::gcm) ) {
    // do GCM authenticated encryption with additional data
}

see types.hpp