/*************************************************************************/ /* crypto.cpp */ /*************************************************************************/ /* This file is part of: */ /* GODOT ENGINE */ /* https://godotengine.org */ /*************************************************************************/ /* Copyright (c) 2007-2021 Juan Linietsky, Ariel Manzur. */ /* Copyright (c) 2014-2021 Godot Engine contributors (cf. AUTHORS.md). */ /* */ /* Permission is hereby granted, free of charge, to any person obtaining */ /* a copy of this software and associated documentation files (the */ /* "Software"), to deal in the Software without restriction, including */ /* without limitation the rights to use, copy, modify, merge, publish, */ /* distribute, sublicense, and/or sell copies of the Software, and to */ /* permit persons to whom the Software is furnished to do so, subject to */ /* the following conditions: */ /* */ /* The above copyright notice and this permission notice shall be */ /* included in all copies or substantial portions of the Software. */ /* */ /* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, */ /* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF */ /* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/ /* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY */ /* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, */ /* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE */ /* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ /*************************************************************************/ #include "crypto.h" #include "core/config/engine.h" #include "core/io/certs_compressed.gen.h" #include "core/io/compression.h" /// Resources CryptoKey *(*CryptoKey::_create)() = nullptr; CryptoKey *CryptoKey::create() { if (_create) { return _create(); } return nullptr; } void CryptoKey::_bind_methods() { ClassDB::bind_method(D_METHOD("save", "path", "public_only"), &CryptoKey::save, DEFVAL(false)); ClassDB::bind_method(D_METHOD("load", "path", "public_only"), &CryptoKey::load, DEFVAL(false)); ClassDB::bind_method(D_METHOD("is_public_only"), &CryptoKey::is_public_only); ClassDB::bind_method(D_METHOD("save_to_string", "public_only"), &CryptoKey::save_to_string, DEFVAL(false)); ClassDB::bind_method(D_METHOD("load_from_string", "string_key", "public_only"), &CryptoKey::load_from_string, DEFVAL(false)); } X509Certificate *(*X509Certificate::_create)() = nullptr; X509Certificate *X509Certificate::create() { if (_create) { return _create(); } return nullptr; } void X509Certificate::_bind_methods() { ClassDB::bind_method(D_METHOD("save", "path"), &X509Certificate::save); ClassDB::bind_method(D_METHOD("load", "path"), &X509Certificate::load); } /// HMACContext void HMACContext::_bind_methods() { ClassDB::bind_method(D_METHOD("start", "hash_type", "key"), &HMACContext::start); ClassDB::bind_method(D_METHOD("update", "data"), &HMACContext::update); ClassDB::bind_method(D_METHOD("finish"), &HMACContext::finish); } HMACContext *(*HMACContext::_create)() = nullptr; HMACContext *HMACContext::create() { if (_create) { return _create(); } ERR_FAIL_V_MSG(nullptr, "HMACContext is not available when the mbedtls module is disabled."); } /// Crypto void (*Crypto::_load_default_certificates)(String p_path) = nullptr; Crypto *(*Crypto::_create)() = nullptr; Crypto *Crypto::create() { if (_create) { return _create(); } ERR_FAIL_V_MSG(nullptr, "Crypto is not available when the mbedtls module is disabled."); } void Crypto::load_default_certificates(String p_path) { if (_load_default_certificates) { _load_default_certificates(p_path); } } PackedByteArray Crypto::hmac_digest(HashingContext::HashType p_hash_type, PackedByteArray p_key, PackedByteArray p_msg) { Ref<HMACContext> ctx = Ref<HMACContext>(HMACContext::create()); ERR_FAIL_COND_V_MSG(ctx.is_null(), PackedByteArray(), "HMAC is not available without mbedtls module."); Error err = ctx->start(p_hash_type, p_key); ERR_FAIL_COND_V(err != OK, PackedByteArray()); err = ctx->update(p_msg); ERR_FAIL_COND_V(err != OK, PackedByteArray()); return ctx->finish(); } // Compares two HMACS for equality without leaking timing information in order to prevent timing attacks. // @see: https://paragonie.com/blog/2015/11/preventing-timing-attacks-on-string-comparison-with-double-hmac-strategy bool Crypto::constant_time_compare(PackedByteArray p_trusted, PackedByteArray p_received) { const uint8_t *t = p_trusted.ptr(); const uint8_t *r = p_received.ptr(); int tlen = p_trusted.size(); int rlen = p_received.size(); // If the lengths are different then nothing else matters. if (tlen != rlen) { return false; } uint8_t v = 0; for (int i = 0; i < tlen; i++) { v |= t[i] ^ r[i]; } return v == 0; } void Crypto::_bind_methods() { ClassDB::bind_method(D_METHOD("generate_random_bytes", "size"), &Crypto::generate_random_bytes); ClassDB::bind_method(D_METHOD("generate_rsa", "size"), &Crypto::generate_rsa); ClassDB::bind_method(D_METHOD("generate_self_signed_certificate", "key", "issuer_name", "not_before", "not_after"), &Crypto::generate_self_signed_certificate, DEFVAL("CN=myserver,O=myorganisation,C=IT"), DEFVAL("20140101000000"), DEFVAL("20340101000000")); ClassDB::bind_method(D_METHOD("sign", "hash_type", "hash", "key"), &Crypto::sign); ClassDB::bind_method(D_METHOD("verify", "hash_type", "hash", "signature", "key"), &Crypto::verify); ClassDB::bind_method(D_METHOD("encrypt", "key", "plaintext"), &Crypto::encrypt); ClassDB::bind_method(D_METHOD("decrypt", "key", "ciphertext"), &Crypto::decrypt); ClassDB::bind_method(D_METHOD("hmac_digest", "hash_type", "key", "msg"), &Crypto::hmac_digest); ClassDB::bind_method(D_METHOD("constant_time_compare", "trusted", "received"), &Crypto::constant_time_compare); } /// Resource loader/saver RES ResourceFormatLoaderCrypto::load(const String &p_path, const String &p_original_path, Error *r_error, bool p_use_sub_threads, float *r_progress, CacheMode p_cache_mode) { String el = p_path.get_extension().to_lower(); if (el == "crt") { X509Certificate *cert = X509Certificate::create(); if (cert) { cert->load(p_path); } return cert; } else if (el == "key") { CryptoKey *key = CryptoKey::create(); if (key) { key->load(p_path, false); } return key; } else if (el == "pub") { CryptoKey *key = CryptoKey::create(); if (key) { key->load(p_path, true); } return key; } return nullptr; } void ResourceFormatLoaderCrypto::get_recognized_extensions(List<String> *p_extensions) const { p_extensions->push_back("crt"); p_extensions->push_back("key"); p_extensions->push_back("pub"); } bool ResourceFormatLoaderCrypto::handles_type(const String &p_type) const { return p_type == "X509Certificate" || p_type == "CryptoKey"; } String ResourceFormatLoaderCrypto::get_resource_type(const String &p_path) const { String el = p_path.get_extension().to_lower(); if (el == "crt") { return "X509Certificate"; } else if (el == "key" || el == "pub") { return "CryptoKey"; } return ""; } Error ResourceFormatSaverCrypto::save(const String &p_path, const RES &p_resource, uint32_t p_flags) { Error err; Ref<X509Certificate> cert = p_resource; Ref<CryptoKey> key = p_resource; if (cert.is_valid()) { err = cert->save(p_path); } else if (key.is_valid()) { String el = p_path.get_extension().to_lower(); err = key->save(p_path, el == "pub"); } else { ERR_FAIL_V(ERR_INVALID_PARAMETER); } ERR_FAIL_COND_V_MSG(err != OK, err, "Cannot save Crypto resource to file '" + p_path + "'."); return OK; } void ResourceFormatSaverCrypto::get_recognized_extensions(const RES &p_resource, List<String> *p_extensions) const { const X509Certificate *cert = Object::cast_to<X509Certificate>(*p_resource); const CryptoKey *key = Object::cast_to<CryptoKey>(*p_resource); if (cert) { p_extensions->push_back("crt"); } if (key) { if (!key->is_public_only()) { p_extensions->push_back("key"); } p_extensions->push_back("pub"); } } bool ResourceFormatSaverCrypto::recognize(const RES &p_resource) const { return Object::cast_to<X509Certificate>(*p_resource) || Object::cast_to<CryptoKey>(*p_resource); }