tag | 3247f94bbd981608b1f1596013b9b49f326fd33f | |
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tagger | mw <megan@cryptoworkshop.com> | Wed Aug 18 14:50:14 2021 +1000 |
object | 2dcd269c2852ed53de369d55423fb2febb1b865d |
Version 3.3.1
commit | 2dcd269c2852ed53de369d55423fb2febb1b865d | [log] [tgz] |
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author | mw <megan@cryptoworkshop.com> | Wed Aug 18 14:49:19 2021 +1000 |
committer | mw <megan@cryptoworkshop.com> | Wed Aug 18 14:49:19 2021 +1000 |
tree | a15fb6f950ad6e61445266f3981340c4c860d030 | |
parent | f5b413affc5699af2453b31bbe59e2111787ed13 [diff] |
Version 3.3.1
A Dart library for encryption and decryption. In this release, most of the classes are ports of Bouncy Castle from Java to Dart. The porting is almost always direct except for some classes that had been added to ease the use of low level data.
To make sure nothing fails, tests and benchmarks for every algorithm are provided. The expected results are taken from the Bouncy Castle Java version and also from standards, and matched against the results got from Pointy Castle.
This library was adopted from the original project at https://github.com/PointyCastle/pointycastle at the request of the authors to help support ongoing development. A list of major contributors is provided at contributors.md
This library is now ported to non-nullable-by-default, a breaking language feature released by the Dart team! See https://dart.dev/null-safety and https://dart.dev/null-safety/migration-guide for more details. Please note that both null-safe and non-null-safe versions are available (v3.x.x-nullsafety for null-safe, v2.x.x for non-null-safe). However, only the null-safe version of this library is actively maintained.
Pointycastle implements a large set of algorithms. They must be instantiated and then initialized with their parameters. Different algorithms have different parameter classes, which represent the arguments to that algorithm. The relevant parameter type is provided for all the algorithms. To initialize an algorithm, call the init method:
var algorithmVar = /* instantiate algorithm using registry here */ ; var parameter = /* instantiate relevant parameter class here */ ; algorithmVar.init(parameter);
Some algorithms will ask for more than just a parameter object in the initialization step. Once you have identified the classes you intend to use in your project, it is recommended that you view the API docs at https://pub.dev/documentation/pointycastle/latest/ to find the specifics of the methods from the class you want to use.
In this release, the following algorithms are implemented:
(Most of the below are keywords for algorithms which can be used directly with the registry. The registry is an easy way to instantiate classes in PointyCastle. See “Using the Registry” for more).
AEAD ciphers: To use with the registry, instantiate like this AEADCipher('ChaCha20-Poly1305')
. Ciphers use AEADParameters
to initialize.
Block ciphers: To use with the registry, instantiate like this PaddedBlockCipher('AES/SomeBlockModeHere/SomePaddingHere')
or like this StreamCipher('AES/SomeStreamModeHere')
. See sections below for modes and paddings.
Block modes of operation: Most modes use ParametersWithIV
to initialize. ECB uses KeyParameter
and GCM uses AEADParameters
.
Stream modes of operation: All modes use ParametersWithIV
to initialize.
Paddings:
Asymmetric block ciphers: Instantiate using the registry like this AsymmetricBlockCipher('RSA/SomeEncodingHere')
. Initialization requires a RSAPrivateKey
or RSAPublicKey
.
Asymmetric block cipher encodings:
Stream ciphers: Instantiation using registry is like this StreamCipher('ChaCha20/20')
. Initialization requires a ParametersWithIV
.
Digests: Instantiate using registry like this Digest('Keccak/384')
. No initialization is necessary.
MACs: Instantiate using registry like this Mac('SomeBlockCipher/CMAC')
or Mac('SomeDigest/HMAC)
or Mac(SomeBlockCipher/Poly1305)
. CMAC and HMAC require a KeyParameter
and Poly1305 requires a ParametersWithIV
.
Signatures: Instantiate using registry like this Signer('SomeDigestHere/(DET-)ECDSA')
or Signer('SomeDigestHere/RSA')
Password based key derivators: Instantiation using registry like this KeyDerivator('SomeDigestHere/HMAC/PBKDF2')
or KeyDerivator('scrypt/argon2')
. To initialize, you'll need a Pbkdf2Parameters
, ScryptParameters
, or Argon2Parameters
.
HMAC based key derivators: Instantiate using registry like this KeyDerivator('SomeDigestHere/HKDF')
. To initialize, use an HkdfParameters
.
Asymmetric key generators Instantiate using registry like this KeyDerivator('RSA')
. To initialize, use ECKeyGeneratorParameters
or RSAKeyGeneratorParameters
.
Secure PRNGs:
There are two ways to instantiate objects that implement the algorithms:
Using the registry, the algorithm name is provided to high-level class factories.
This is especially convenient when an algorithm involves multiple algorithm implementation classes to implement. All the necessary classes can all be instantiated with a single name (e.g. “SHA-256/HMAC” or “SHA-1/HMAC/PBKDF2” or “AES/CBC/PKCS7”), and they are automatically combined together with the correct values.
For example,
final sha256 = Digest("SHA-256"); final sha1 = Digest("SHA-1"); final md5 = Digest("MD5"); final hmacSha256 = Mac("SHA-256/HMAC"); final hmacSha1 = Mac("SHA-1/HMAC"); final hmacMd5 = Mac("MD5/HMAC"); final derivator = KeyDerivator("SHA-1/HMAC/PBKDF2"); final signer = Signer("SHA-256/RSA");
Without the registry, each implementation class must be instantiated using its constructor.
If an algorithm involves multiple algorithm implementation classes, they each have to be individually instantiated and combined together with the correct values.
For example,
final sha256 = SHA256Digest(); final sha1 = SHA1Digest(); final md5 = MD5Digest(); final hmacSha256 = HMac(SHA256Digest(), 64); final hmacSha512 = HMac(SHA512Digest(), 128); final hmacMd5 = HMac(MD5Digest(), 64); final derivator = PBKDF2KeyDerivator(HMac(SHA256Digest(), 64)); final signer = RSASigner(SHA256Digest(), '0609608648016503040201');
Using the registry means that all algorithms will be imported by default, which can increase the compiled size of your program.
To avoid this, instantiate all classes directly by using the constructors. But which classes can be instantiated with its constructor will depend on which libraries have been imported.
A program can take one of these three approaches for importing Point Castle libraries:
The “pointycastle.dart” file exports:
But it does not export any of the algorithm implementation classes.
import "package:pointycastle/pointycastle.dart";
With this import, none of the implementation classes can be instantiated directly. The program can only use the registry.
For example,
final sha256 = Digest("SHA-256"); // final md5 = MD5Digest(); // not available final p = Padding("PKCS7"); // final s = FortunaRandom(); // not available
The “export.dart” file exports:
That is, everything!
import "package:pointycastle/export.dart";
With this import, all of the implementation classes can be instantiated directly. The program can also use the registry.
For example, this works without any additional imports:
final sha256 = Digest("SHA-256"); final md5 = MD5Digest(); final p = Padding("PKCS7"); final s = FortunaRandom();
The “api.dart” exports only:
It does not include the implementations of the interfaces, nor any algorithm implementation class.
import "package:pointycastle/api.dart"; // additional imports will be needed
With this import, only some of the implementation classes can be instantiated directly (i.e. those that are also explicitly imported). The program can also use the registry.
For example, the following only works because of the additional imports:
// In addition to "package:pointycastle/api.dart": import "package:pointycastle/digests/sha256.dart"; import "package:pointycastle/digests/md5.dart" import 'package:pointycastle/paddings/pkcs7.dart'; final sha256 = Digest("SHA-256"); final md5 = MD5Digest(); final p = Padding("PKCS7"); // final s = FortunaRandom(); // not available without 'package:pointycastle/random/fortuna_random.dart'
Some articles on how to use some of Pointy Castle's features can be found under the tutorials directory in the sources.
Note: the above links are to the most recent versions on the master branch on GitHub. They may be different from the version on pub.dev.