1/**************************************************************************/
2/* crypto.cpp */
3/**************************************************************************/
4/* This file is part of: */
5/* GODOT ENGINE */
6/* https://godotengine.org */
7/**************************************************************************/
8/* Copyright (c) 2014-present Godot Engine contributors (see AUTHORS.md). */
9/* Copyright (c) 2007-2014 Juan Linietsky, Ariel Manzur. */
10/* */
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21/* */
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23/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF */
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29/**************************************************************************/
30
31#include "crypto.h"
32
33#include "core/config/engine.h"
34#include "core/io/certs_compressed.gen.h"
35#include "core/io/compression.h"
36
37/// Resources
38
39CryptoKey *(*CryptoKey::_create)() = nullptr;
40CryptoKey *CryptoKey::create() {
41 if (_create) {
42 return _create();
43 }
44 return nullptr;
45}
46
47void CryptoKey::_bind_methods() {
48 ClassDB::bind_method(D_METHOD("save", "path", "public_only"), &CryptoKey::save, DEFVAL(false));
49 ClassDB::bind_method(D_METHOD("load", "path", "public_only"), &CryptoKey::load, DEFVAL(false));
50 ClassDB::bind_method(D_METHOD("is_public_only"), &CryptoKey::is_public_only);
51 ClassDB::bind_method(D_METHOD("save_to_string", "public_only"), &CryptoKey::save_to_string, DEFVAL(false));
52 ClassDB::bind_method(D_METHOD("load_from_string", "string_key", "public_only"), &CryptoKey::load_from_string, DEFVAL(false));
53}
54
55X509Certificate *(*X509Certificate::_create)() = nullptr;
56X509Certificate *X509Certificate::create() {
57 if (_create) {
58 return _create();
59 }
60 return nullptr;
61}
62
63void X509Certificate::_bind_methods() {
64 ClassDB::bind_method(D_METHOD("save", "path"), &X509Certificate::save);
65 ClassDB::bind_method(D_METHOD("load", "path"), &X509Certificate::load);
66 ClassDB::bind_method(D_METHOD("save_to_string"), &X509Certificate::save_to_string);
67 ClassDB::bind_method(D_METHOD("load_from_string", "string"), &X509Certificate::load_from_string);
68}
69
70/// TLSOptions
71
72Ref<TLSOptions> TLSOptions::client(Ref<X509Certificate> p_trusted_chain, const String &p_common_name_override) {
73 Ref<TLSOptions> opts;
74 opts.instantiate();
75 opts->trusted_ca_chain = p_trusted_chain;
76 opts->common_name = p_common_name_override;
77 opts->verify_mode = TLS_VERIFY_FULL;
78 return opts;
79}
80
81Ref<TLSOptions> TLSOptions::client_unsafe(Ref<X509Certificate> p_trusted_chain) {
82 Ref<TLSOptions> opts;
83 opts.instantiate();
84 opts->trusted_ca_chain = p_trusted_chain;
85 if (p_trusted_chain.is_null()) {
86 opts->verify_mode = TLS_VERIFY_NONE;
87 } else {
88 opts->verify_mode = TLS_VERIFY_CERT;
89 }
90 return opts;
91}
92
93Ref<TLSOptions> TLSOptions::server(Ref<CryptoKey> p_own_key, Ref<X509Certificate> p_own_certificate) {
94 Ref<TLSOptions> opts;
95 opts.instantiate();
96 opts->server_mode = true;
97 opts->own_certificate = p_own_certificate;
98 opts->private_key = p_own_key;
99 opts->verify_mode = TLS_VERIFY_NONE;
100 return opts;
101}
102
103void TLSOptions::_bind_methods() {
104 ClassDB::bind_static_method("TLSOptions", D_METHOD("client", "trusted_chain", "common_name_override"), &TLSOptions::client, DEFVAL(Ref<X509Certificate>()), DEFVAL(String()));
105 ClassDB::bind_static_method("TLSOptions", D_METHOD("client_unsafe", "trusted_chain"), &TLSOptions::client_unsafe, DEFVAL(Ref<X509Certificate>()));
106 ClassDB::bind_static_method("TLSOptions", D_METHOD("server", "key", "certificate"), &TLSOptions::server);
107}
108
109/// HMACContext
110
111void HMACContext::_bind_methods() {
112 ClassDB::bind_method(D_METHOD("start", "hash_type", "key"), &HMACContext::start);
113 ClassDB::bind_method(D_METHOD("update", "data"), &HMACContext::update);
114 ClassDB::bind_method(D_METHOD("finish"), &HMACContext::finish);
115}
116
117HMACContext *(*HMACContext::_create)() = nullptr;
118HMACContext *HMACContext::create() {
119 if (_create) {
120 return _create();
121 }
122 ERR_FAIL_V_MSG(nullptr, "HMACContext is not available when the mbedtls module is disabled.");
123}
124
125/// Crypto
126
127void (*Crypto::_load_default_certificates)(String p_path) = nullptr;
128Crypto *(*Crypto::_create)() = nullptr;
129Crypto *Crypto::create() {
130 if (_create) {
131 return _create();
132 }
133 ERR_FAIL_V_MSG(nullptr, "Crypto is not available when the mbedtls module is disabled.");
134}
135
136void Crypto::load_default_certificates(String p_path) {
137 if (_load_default_certificates) {
138 _load_default_certificates(p_path);
139 }
140}
141
142PackedByteArray Crypto::hmac_digest(HashingContext::HashType p_hash_type, PackedByteArray p_key, PackedByteArray p_msg) {
143 Ref<HMACContext> ctx = Ref<HMACContext>(HMACContext::create());
144 ERR_FAIL_COND_V_MSG(ctx.is_null(), PackedByteArray(), "HMAC is not available without mbedtls module.");
145 Error err = ctx->start(p_hash_type, p_key);
146 ERR_FAIL_COND_V(err != OK, PackedByteArray());
147 err = ctx->update(p_msg);
148 ERR_FAIL_COND_V(err != OK, PackedByteArray());
149 return ctx->finish();
150}
151
152// Compares two HMACS for equality without leaking timing information in order to prevent timing attacks.
153// @see: https://paragonie.com/blog/2015/11/preventing-timing-attacks-on-string-comparison-with-double-hmac-strategy
154bool Crypto::constant_time_compare(PackedByteArray p_trusted, PackedByteArray p_received) {
155 const uint8_t *t = p_trusted.ptr();
156 const uint8_t *r = p_received.ptr();
157 int tlen = p_trusted.size();
158 int rlen = p_received.size();
159 // If the lengths are different then nothing else matters.
160 if (tlen != rlen) {
161 return false;
162 }
163
164 uint8_t v = 0;
165 for (int i = 0; i < tlen; i++) {
166 v |= t[i] ^ r[i];
167 }
168 return v == 0;
169}
170
171void Crypto::_bind_methods() {
172 ClassDB::bind_method(D_METHOD("generate_random_bytes", "size"), &Crypto::generate_random_bytes);
173 ClassDB::bind_method(D_METHOD("generate_rsa", "size"), &Crypto::generate_rsa);
174 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"));
175 ClassDB::bind_method(D_METHOD("sign", "hash_type", "hash", "key"), &Crypto::sign);
176 ClassDB::bind_method(D_METHOD("verify", "hash_type", "hash", "signature", "key"), &Crypto::verify);
177 ClassDB::bind_method(D_METHOD("encrypt", "key", "plaintext"), &Crypto::encrypt);
178 ClassDB::bind_method(D_METHOD("decrypt", "key", "ciphertext"), &Crypto::decrypt);
179 ClassDB::bind_method(D_METHOD("hmac_digest", "hash_type", "key", "msg"), &Crypto::hmac_digest);
180 ClassDB::bind_method(D_METHOD("constant_time_compare", "trusted", "received"), &Crypto::constant_time_compare);
181}
182
183/// Resource loader/saver
184
185Ref<Resource> 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) {
186 String el = p_path.get_extension().to_lower();
187 if (el == "crt") {
188 X509Certificate *cert = X509Certificate::create();
189 if (cert) {
190 cert->load(p_path);
191 }
192 return cert;
193 } else if (el == "key") {
194 CryptoKey *key = CryptoKey::create();
195 if (key) {
196 key->load(p_path, false);
197 }
198 return key;
199 } else if (el == "pub") {
200 CryptoKey *key = CryptoKey::create();
201 if (key) {
202 key->load(p_path, true);
203 }
204 return key;
205 }
206 return nullptr;
207}
208
209void ResourceFormatLoaderCrypto::get_recognized_extensions(List<String> *p_extensions) const {
210 p_extensions->push_back("crt");
211 p_extensions->push_back("key");
212 p_extensions->push_back("pub");
213}
214
215bool ResourceFormatLoaderCrypto::handles_type(const String &p_type) const {
216 return p_type == "X509Certificate" || p_type == "CryptoKey";
217}
218
219String ResourceFormatLoaderCrypto::get_resource_type(const String &p_path) const {
220 String el = p_path.get_extension().to_lower();
221 if (el == "crt") {
222 return "X509Certificate";
223 } else if (el == "key" || el == "pub") {
224 return "CryptoKey";
225 }
226 return "";
227}
228
229Error ResourceFormatSaverCrypto::save(const Ref<Resource> &p_resource, const String &p_path, uint32_t p_flags) {
230 Error err;
231 Ref<X509Certificate> cert = p_resource;
232 Ref<CryptoKey> key = p_resource;
233 if (cert.is_valid()) {
234 err = cert->save(p_path);
235 } else if (key.is_valid()) {
236 String el = p_path.get_extension().to_lower();
237 err = key->save(p_path, el == "pub");
238 } else {
239 ERR_FAIL_V(ERR_INVALID_PARAMETER);
240 }
241 ERR_FAIL_COND_V_MSG(err != OK, err, "Cannot save Crypto resource to file '" + p_path + "'.");
242 return OK;
243}
244
245void ResourceFormatSaverCrypto::get_recognized_extensions(const Ref<Resource> &p_resource, List<String> *p_extensions) const {
246 const X509Certificate *cert = Object::cast_to<X509Certificate>(*p_resource);
247 const CryptoKey *key = Object::cast_to<CryptoKey>(*p_resource);
248 if (cert) {
249 p_extensions->push_back("crt");
250 }
251 if (key) {
252 if (!key->is_public_only()) {
253 p_extensions->push_back("key");
254 }
255 p_extensions->push_back("pub");
256 }
257}
258
259bool ResourceFormatSaverCrypto::recognize(const Ref<Resource> &p_resource) const {
260 return Object::cast_to<X509Certificate>(*p_resource) || Object::cast_to<CryptoKey>(*p_resource);
261}
262