[3.x] Backport AESContext, RSA public keys, encryption, decryption, sign, and verify.

core/crypto/aes_context.cpp

@@ -0,0 +1,116 @@
+/*************************************************************************/
+/*  aes_context.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 "core/crypto/aes_context.h"
+
+Error AESContext::start(Mode p_mode, PoolByteArray p_key, PoolByteArray p_iv) {
+	ERR_FAIL_COND_V_MSG(mode != MODE_MAX, ERR_ALREADY_IN_USE, "AESContext already started. Call 'finish' before starting a new one.");
+	ERR_FAIL_COND_V_MSG(p_mode < 0 || p_mode >= MODE_MAX, ERR_INVALID_PARAMETER, "Invalid mode requested.");
+	// Key check.
+	int key_bits = p_key.size() << 3;
+	ERR_FAIL_COND_V_MSG(key_bits != 128 && key_bits != 256, ERR_INVALID_PARAMETER, "AES key must be either 16 or 32 bytes");
+	// Initialization vector.
+	if (p_mode == MODE_CBC_ENCRYPT || p_mode == MODE_CBC_DECRYPT) {
+		ERR_FAIL_COND_V_MSG(p_iv.size() != 16, ERR_INVALID_PARAMETER, "The initialization vector (IV) must be exactly 16 bytes.");
+		iv.resize(0);
+		iv.append_array(p_iv);
+	}
+	// Encryption/decryption key.
+	if (p_mode == MODE_CBC_ENCRYPT || p_mode == MODE_ECB_ENCRYPT) {
+		ctx.set_encode_key(p_key.read().ptr(), key_bits);
+	} else {
+		ctx.set_decode_key(p_key.read().ptr(), key_bits);
+	}
+	mode = p_mode;
+	return OK;
+}
+
+PoolByteArray AESContext::update(PoolByteArray p_src) {
+	ERR_FAIL_COND_V_MSG(mode < 0 || mode >= MODE_MAX, PoolByteArray(), "AESContext not started. Call 'start' before calling 'update'.");
+	int len = p_src.size();
+	ERR_FAIL_COND_V_MSG(len % 16, PoolByteArray(), "The number of bytes to be encrypted must be multiple of 16. Add padding if needed");
+	PoolByteArray out;
+	out.resize(len);
+	const uint8_t *src_ptr = p_src.read().ptr();
+	uint8_t *out_ptr = out.write().ptr();
+	switch (mode) {
+		case MODE_ECB_ENCRYPT: {
+			for (int i = 0; i < len; i += 16) {
+				Error err = ctx.encrypt_ecb(src_ptr + i, out_ptr + i);
+				ERR_FAIL_COND_V(err != OK, PoolByteArray());
+			}
+		} break;
+		case MODE_ECB_DECRYPT: {
+			for (int i = 0; i < len; i += 16) {
+				Error err = ctx.decrypt_ecb(src_ptr + i, out_ptr + i);
+				ERR_FAIL_COND_V(err != OK, PoolByteArray());
+			}
+		} break;
+		case MODE_CBC_ENCRYPT: {
+			Error err = ctx.encrypt_cbc(len, iv.write().ptr(), p_src.read().ptr(), out.write().ptr());
+			ERR_FAIL_COND_V(err != OK, PoolByteArray());
+		} break;
+		case MODE_CBC_DECRYPT: {
+			Error err = ctx.decrypt_cbc(len, iv.write().ptr(), p_src.read().ptr(), out.write().ptr());
+			ERR_FAIL_COND_V(err != OK, PoolByteArray());
+		} break;
+		default:
+			ERR_FAIL_V_MSG(PoolByteArray(), "Bug!");
+	}
+	return out;
+}
+
+PoolByteArray AESContext::get_iv_state() {
+	ERR_FAIL_COND_V_MSG(mode != MODE_CBC_ENCRYPT && mode != MODE_CBC_DECRYPT, PoolByteArray(), "Calling 'get_iv_state' only makes sense when the context is started in CBC mode.");
+	PoolByteArray out;
+	out.append_array(iv);
+	return out;
+}
+
+void AESContext::finish() {
+	mode = MODE_MAX;
+	iv.resize(0);
+}
+
+void AESContext::_bind_methods() {
+	ClassDB::bind_method(D_METHOD("start", "mode", "key", "iv"), &AESContext::start, DEFVAL(PoolByteArray()));
+	ClassDB::bind_method(D_METHOD("update", "src"), &AESContext::update);
+	ClassDB::bind_method(D_METHOD("get_iv_state"), &AESContext::get_iv_state);
+	ClassDB::bind_method(D_METHOD("finish"), &AESContext::finish);
+	BIND_ENUM_CONSTANT(MODE_ECB_ENCRYPT);
+	BIND_ENUM_CONSTANT(MODE_ECB_DECRYPT);
+	BIND_ENUM_CONSTANT(MODE_CBC_ENCRYPT);
+	BIND_ENUM_CONSTANT(MODE_CBC_DECRYPT);
+	BIND_ENUM_CONSTANT(MODE_MAX);
+}
+
+AESContext::AESContext() {
+	mode = MODE_MAX;
+}

core/crypto/aes_context.h

@@ -0,0 +1,68 @@
+/*************************************************************************/
+/*  aes_context.h                                                        */
+/*************************************************************************/
+/*                       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.                */
+/*************************************************************************/
+
+#ifndef AES_CONTEXT_H
+#define AES_CONTEXT_H
+
+#include "core/crypto/crypto_core.h"
+#include "core/reference.h"
+
+class AESContext : public Reference {
+	GDCLASS(AESContext, Reference);
+
+public:
+	enum Mode {
+		MODE_ECB_ENCRYPT,
+		MODE_ECB_DECRYPT,
+		MODE_CBC_ENCRYPT,
+		MODE_CBC_DECRYPT,
+		MODE_MAX
+	};
+
+private:
+	Mode mode;
+	CryptoCore::AESContext ctx;
+	PoolByteArray iv;
+
+protected:
+	static void _bind_methods();
+
+public:
+	Error start(Mode p_mode, PoolByteArray p_key, PoolByteArray p_iv = PoolByteArray());
+	PoolByteArray update(PoolByteArray p_src);
+	PoolByteArray get_iv_state();
+	void finish();
+
+	AESContext();
+};
+
+VARIANT_ENUM_CAST(AESContext::Mode);
+
+#endif // AES_CONTEXT_H

core/crypto/crypto.cpp

@@ -44,8 +44,11 @@ CryptoKey *CryptoKey::create() {
 }
 
 void CryptoKey::_bind_methods() {
-	ClassDB::bind_method(D_METHOD("save", "path"), &CryptoKey::save);
-	ClassDB::bind_method(D_METHOD("load", "path"), &CryptoKey::load);
+	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)() = NULL;
@@ -80,6 +83,10 @@ 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);
 }
 
 Crypto::Crypto() {
@@ -98,7 +105,12 @@ RES ResourceFormatLoaderCrypto::load(const String &p_path, const String &p_origi
 	} else if (el == "key") {
 		CryptoKey *key = CryptoKey::create();
 		if (key)
-			key->load(p_path);
+			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 NULL;
@@ -108,6 +120,7 @@ void ResourceFormatLoaderCrypto::get_recognized_extensions(List<String> *p_exten
 
 	p_extensions->push_back("crt");
 	p_extensions->push_back("key");
+	p_extensions->push_back("pub");
 }
 
 bool ResourceFormatLoaderCrypto::handles_type(const String &p_type) const {
@@ -120,7 +133,7 @@ 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")
+	else if (el == "key" || el == "pub")
 		return "CryptoKey";
 	return "";
 }
@@ -133,7 +146,8 @@ Error ResourceFormatSaverCrypto::save(const String &p_path, const RES &p_resourc
 	if (cert.is_valid()) {
 		err = cert->save(p_path);
 	} else if (key.is_valid()) {
-		err = key->save(p_path);
+		String el = p_path.get_extension().to_lower();
+		err = key->save(p_path, el == "pub");
 	} else {
 		ERR_FAIL_V(ERR_INVALID_PARAMETER);
 	}
@@ -149,7 +163,10 @@ void ResourceFormatSaverCrypto::get_recognized_extensions(const RES &p_resource,
 		p_extensions->push_back("crt");
 	}
 	if (key) {
-		p_extensions->push_back("key");
+		if (!key->is_public_only()) {
+			p_extensions->push_back("key");
+		}
+		p_extensions->push_back("pub");
 	}
 }
 bool ResourceFormatSaverCrypto::recognize(const RES &p_resource) const {

core/crypto/crypto.h

@@ -31,6 +31,7 @@
 #ifndef CRYPTO_H
 #define CRYPTO_H
 
+#include "core/crypto/hashing_context.h"
 #include "core/reference.h"
 #include "core/resource.h"
 
@@ -46,8 +47,11 @@ class CryptoKey : public Resource {
 
 public:
 	static CryptoKey *create();
-	virtual Error load(String p_path) = 0;
-	virtual Error save(String p_path) = 0;
+	virtual Error load(String p_path, bool p_public_only = false) = 0;
+	virtual Error save(String p_path, bool p_public_only = false) = 0;
+	virtual String save_to_string(bool p_public_only = false) = 0;
+	virtual Error load_from_string(String p_string_key, bool p_public_only = false) = 0;
+	virtual bool is_public_only() const = 0;
 };
 
 class X509Certificate : public Resource {
@@ -80,6 +84,11 @@ class Crypto : public Reference {
 	virtual Ref<CryptoKey> generate_rsa(int p_bytes) = 0;
 	virtual Ref<X509Certificate> generate_self_signed_certificate(Ref<CryptoKey> p_key, String p_issuer_name, String p_not_before, String p_not_after) = 0;
 
+	virtual Vector<uint8_t> sign(HashingContext::HashType p_hash_type, Vector<uint8_t> p_hash, Ref<CryptoKey> p_key) = 0;
+	virtual bool verify(HashingContext::HashType p_hash_type, Vector<uint8_t> p_hash, Vector<uint8_t> p_signature, Ref<CryptoKey> p_key) = 0;
+	virtual Vector<uint8_t> encrypt(Ref<CryptoKey> p_key, Vector<uint8_t> p_plaintext) = 0;
+	virtual Vector<uint8_t> decrypt(Ref<CryptoKey> p_key, Vector<uint8_t> p_ciphertext) = 0;
+
 	Crypto();
 };
 

core/crypto/crypto_core.cpp

@@ -145,6 +145,16 @@ Error CryptoCore::AESContext::decrypt_ecb(const uint8_t p_src[16], uint8_t r_dst
 	return ret ? FAILED : OK;
 }
 
+Error CryptoCore::AESContext::encrypt_cbc(size_t p_length, uint8_t r_iv[16], const uint8_t *p_src, uint8_t *r_dst) {
+	int ret = mbedtls_aes_crypt_cbc((mbedtls_aes_context *)ctx, MBEDTLS_AES_ENCRYPT, p_length, r_iv, p_src, r_dst);
+	return ret ? FAILED : OK;
+}
+
+Error CryptoCore::AESContext::decrypt_cbc(size_t p_length, uint8_t r_iv[16], const uint8_t *p_src, uint8_t *r_dst) {
+	int ret = mbedtls_aes_crypt_cbc((mbedtls_aes_context *)ctx, MBEDTLS_AES_DECRYPT, p_length, r_iv, p_src, r_dst);
+	return ret ? FAILED : OK;
+}
+
 // CryptoCore
 String CryptoCore::b64_encode_str(const uint8_t *p_src, int p_src_len) {
 	int b64len = p_src_len / 3 * 4 + 4 + 1;

core/crypto/crypto_core.h

@@ -91,6 +91,8 @@ class CryptoCore {
 		Error set_decode_key(const uint8_t *p_key, size_t p_bits);
 		Error encrypt_ecb(const uint8_t p_src[16], uint8_t r_dst[16]);
 		Error decrypt_ecb(const uint8_t p_src[16], uint8_t r_dst[16]);
+		Error encrypt_cbc(size_t p_length, uint8_t r_iv[16], const uint8_t *p_src, uint8_t *r_dst);
+		Error decrypt_cbc(size_t p_length, uint8_t r_iv[16], const uint8_t *p_src, uint8_t *r_dst);
 	};
 
 	static String b64_encode_str(const uint8_t *p_src, int p_src_len);

core/register_core_types.cpp

@@ -34,6 +34,7 @@
 #include "core/class_db.h"
 #include "core/compressed_translation.h"
 #include "core/core_string_names.h"
+#include "core/crypto/aes_context.h"
 #include "core/crypto/crypto.h"
 #include "core/crypto/hashing_context.h"
 #include "core/engine.h"
@@ -159,6 +160,7 @@ void register_core_types() {
 
 	// Crypto
 	ClassDB::register_class<HashingContext>();
+	ClassDB::register_class<AESContext>();
 	ClassDB::register_custom_instance_class<X509Certificate>();
 	ClassDB::register_custom_instance_class<CryptoKey>();
 	ClassDB::register_custom_instance_class<Crypto>();