1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
|
<?xml version="1.0" encoding="UTF-8" ?>
<class name="Crypto" inherits="Reference" version="4.0">
<brief_description>
Access to advanced cryptographic functionalities.
</brief_description>
<description>
The Crypto class allows you to access some more advanced cryptographic functionalities in Godot.
For now, this includes generating cryptographically secure random bytes, RSA keys and self-signed X509 certificates generation, asymmetric key encryption/decryption, and signing/verification.
[codeblocks]
[gdscript]
extends Node
var crypto = Crypto.new()
var key = CryptoKey.new()
var cert = X509Certificate.new()
func _ready():
# Generate new RSA key.
key = crypto.generate_rsa(4096)
# Generate new self-signed certificate with the given key.
cert = crypto.generate_self_signed_certificate(key, "CN=mydomain.com,O=My Game Company,C=IT")
# Save key and certificate in the user folder.
key.save("user://generated.key")
cert.save("user://generated.crt")
# Encryption
var data = "Some data"
var encrypted = crypto.encrypt(key, data.to_utf8())
# Decryption
var decrypted = crypto.decrypt(key, encrypted)
# Signing
var signature = crypto.sign(HashingContext.HASH_SHA256, data.sha256_buffer(), key)
# Verifying
var verified = crypto.verify(HashingContext.HASH_SHA256, data.sha256_buffer(), signature, key)
# Checks
assert(verified)
assert(data.to_utf8() == decrypted)
[/gdscript]
[csharp]
using Godot;
using System;
using System.Diagnostics;
public class CryptoNode : Node
{
public Crypto Crypto = new Crypto();
public CryptoKey Key = new CryptoKey();
public X509Certificate Cert = new X509Certificate();
public override void _Ready()
{
// Generate new RSA key.
Key = Crypto.GenerateRsa(4096);
// Generate new self-signed certificate with the given key.
Cert = Crypto.GenerateSelfSignedCertificate(Key, "CN=mydomain.com,O=My Game Company,C=IT");
// Save key and certificate in the user folder.
Key.Save("user://generated.key");
Cert.Save("user://generated.crt");
// Encryption
string data = "Some data";
byte[] encrypted = Crypto.Encrypt(Key, data.ToUTF8());
// Decryption
byte[] decrypted = Crypto.Decrypt(Key, encrypted);
// Signing
byte[] signature = Crypto.Sign(HashingContext.HashType.Sha256, Data.SHA256Buffer(), Key);
// Verifying
bool verified = Crypto.Verify(HashingContext.HashType.Sha256, Data.SHA256Buffer(), signature, Key);
// Checks
Debug.Assert(verified);
Debug.Assert(data.ToUTF8() == decrypted);
}
}
[/csharp]
[/codeblocks]
[b]Note:[/b] Not available in HTML5 exports.
</description>
<tutorials>
</tutorials>
<methods>
<method name="constant_time_compare">
<return type="bool">
</return>
<argument index="0" name="trusted" type="PackedByteArray">
</argument>
<argument index="1" name="received" type="PackedByteArray">
</argument>
<description>
Compares two [PackedByteArray]s for equality without leaking timing information in order to prevent timing attacks.
See [url=https://paragonie.com/blog/2015/11/preventing-timing-attacks-on-string-comparison-with-double-hmac-strategy]this blog post[/url] for more information.
</description>
</method>
<method name="decrypt">
<return type="PackedByteArray">
</return>
<argument index="0" name="key" type="CryptoKey">
</argument>
<argument index="1" name="ciphertext" type="PackedByteArray">
</argument>
<description>
Decrypt the given [code]ciphertext[/code] with the provided private [code]key[/code].
[b]Note[/b]: The maximum size of accepted ciphertext is limited by the key size.
</description>
</method>
<method name="encrypt">
<return type="PackedByteArray">
</return>
<argument index="0" name="key" type="CryptoKey">
</argument>
<argument index="1" name="plaintext" type="PackedByteArray">
</argument>
<description>
Encrypt the given [code]plaintext[/code] with the provided public [code]key[/code].
[b]Note[/b]: The maximum size of accepted plaintext is limited by the key size.
</description>
</method>
<method name="generate_random_bytes">
<return type="PackedByteArray">
</return>
<argument index="0" name="size" type="int">
</argument>
<description>
Generates a [PackedByteArray] of cryptographically secure random bytes with given [code]size[/code].
</description>
</method>
<method name="generate_rsa">
<return type="CryptoKey">
</return>
<argument index="0" name="size" type="int">
</argument>
<description>
Generates an RSA [CryptoKey] that can be used for creating self-signed certificates and passed to [method StreamPeerSSL.accept_stream].
</description>
</method>
<method name="generate_self_signed_certificate">
<return type="X509Certificate">
</return>
<argument index="0" name="key" type="CryptoKey">
</argument>
<argument index="1" name="issuer_name" type="String" default=""CN=myserver,O=myorganisation,C=IT"">
</argument>
<argument index="2" name="not_before" type="String" default=""20140101000000"">
</argument>
<argument index="3" name="not_after" type="String" default=""20340101000000"">
</argument>
<description>
Generates a self-signed [X509Certificate] from the given [CryptoKey] and [code]issuer_name[/code]. The certificate validity will be defined by [code]not_before[/code] and [code]not_after[/code] (first valid date and last valid date). The [code]issuer_name[/code] must contain at least "CN=" (common name, i.e. the domain name), "O=" (organization, i.e. your company name), "C=" (country, i.e. 2 lettered ISO-3166 code of the country the organization is based in).
A small example to generate an RSA key and a X509 self-signed certificate.
[codeblocks]
[gdscript]
var crypto = Crypto.new()
# Generate 4096 bits RSA key.
var key = crypto.generate_rsa(4096)
# Generate self-signed certificate using the given key.
var cert = crypto.generate_self_signed_certificate(key, "CN=example.com,O=A Game Company,C=IT")
[/gdscript]
[csharp]
var crypto = new Crypto();
// Generate 4096 bits RSA key.
CryptoKey key = crypto.GenerateRsa(4096);
// Generate self-signed certificate using the given key.
X509Certificate cert = crypto.GenerateSelfSignedCertificate(key, "CN=mydomain.com,O=My Game Company,C=IT");
[/csharp]
[/codeblocks]
</description>
</method>
<method name="hmac_digest">
<return type="PackedByteArray">
</return>
<argument index="0" name="hash_type" type="int" enum="HashingContext.HashType">
</argument>
<argument index="1" name="key" type="PackedByteArray">
</argument>
<argument index="2" name="msg" type="PackedByteArray">
</argument>
<description>
Generates an [url=https://en.wikipedia.org/wiki/HMAC]HMAC[/url] digest of [code]msg[/code] using [code]key[/code]. The [code]hash_type[/code] parameter is the hashing algorithm that is used for the inner and outer hashes.
Currently, only [constant HashingContext.HASH_SHA256] and [constant HashingContext.HASH_SHA1] are supported.
</description>
</method>
<method name="sign">
<return type="PackedByteArray">
</return>
<argument index="0" name="hash_type" type="int" enum="HashingContext.HashType">
</argument>
<argument index="1" name="hash" type="PackedByteArray">
</argument>
<argument index="2" name="key" type="CryptoKey">
</argument>
<description>
Sign a given [code]hash[/code] of type [code]hash_type[/code] with the provided private [code]key[/code].
</description>
</method>
<method name="verify">
<return type="bool">
</return>
<argument index="0" name="hash_type" type="int" enum="HashingContext.HashType">
</argument>
<argument index="1" name="hash" type="PackedByteArray">
</argument>
<argument index="2" name="signature" type="PackedByteArray">
</argument>
<argument index="3" name="key" type="CryptoKey">
</argument>
<description>
Verify that a given [code]signature[/code] for [code]hash[/code] of type [code]hash_type[/code] against the provided public [code]key[/code].
</description>
</method>
</methods>
<constants>
</constants>
</class>
|