Move json, uri, utf and crypto libraries into the VM.

sdk/lib/crypto/crypto_base.dart

+// Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+part of dart.crypto;
+
+/**
+ * Interface for cryptographic hash functions.
+ *
+ * The [add] method is used to add data to the hash. The [close] method
+ * is used to extract the message digest.
+ *
+ * Once the [close] method has been called no more data can be added using the
+ * [add] method. If [add] is called after the first call to [close] a
+ * HashException is thrown.
+ *
+ * If multiple instances of a given Hash is needed the [newInstance]
+ * method can provide a new instance.
+ */
+// TODO(floitsch): make Hash implement Sink, StreamSink or similar.
+abstract class Hash {
+  /**
+   * Add a list of bytes to the hash computation.
+   */
+  add(List<int> data);
+
+  /**
+   * Finish the hash computation and extract the message digest as
+   * a list of bytes.
+   */
+  List<int> close();
+
+  /**
+   * Returns a new instance of this hash function.
+   */
+  Hash newInstance();
+
+  /**
+   * Internal block size of the hash in bytes.
+   *
+   * This is exposed for use by the HMAC class which needs to know the
+   * block size for the [Hash] it is using.
+   */
+  int get blockSize;
+}
+
+/**
+ * SHA1 hash function implementation.
+ */
+abstract class SHA1 implements Hash {
+  factory SHA1() => new _SHA1();
+}
+
+/**
+ * SHA256 hash function implementation.
+ */
+abstract class SHA256 implements Hash {
+  factory SHA256() => new _SHA256();
+}
+
+/**
+ * MD5 hash function implementation.
+ *
+ * WARNING: MD5 has known collisions and should only be used when
+ * required for backwards compatibility.
+ */
+abstract class MD5 implements Hash {
+  factory MD5() => new _MD5();
+}
+
+/**
+ * Hash-based Message Authentication Code support.
+ *
+ * The [add] method is used to add data to the message. The [digest] and
+ * [close] methods are used to extract the message authentication code.
+ */
+// TODO(floitsch): make Hash implement Sink, StreamSink or similar.
+abstract class HMAC {
+  /**
+   * Create an [HMAC] object from a [Hash] and a key.
+   */
+  factory HMAC(Hash hash, List<int> key) => new _HMAC(hash, key);
+
+  /**
+   * Add a list of bytes to the message.
+   */
+  add(List<int> data);
+
+  /**
+   * Perform the actual computation and extract the message digest
+   * as a list of bytes.
+   */
+  List<int> close();
+
+  /**
+   * Extract the message digest as a list of bytes without closing [this].
+   */
+  List<int> get digest;
+
+  /**
+   * Verify that the HMAC computed for the data so far matches the
+   * given message digest.
+   *
+   * This method should be used instead of memcmp-style comparisons
+   * to avoid leaking information via timing.
+   *
+   * Throws an exception if the given digest does not have the same
+   * size as the digest computed by this HMAC instance.
+   */
+  bool verify(List<int> digest);
+}
+
+/**
+ * Utility methods for working with message digests.
+ */
+abstract class CryptoUtils {
+  /**
+   * Convert a list of bytes (for example a message digest) into a hex
+   * string.
+   */
+  static String bytesToHex(List<int> bytes) {
+    return _CryptoUtils.bytesToHex(bytes);
+  }
+
+  /**
+   * Converts a list of bytes (for example a message digest) into a
+   * base64 encoded string optionally broken up in to lines of
+   * [lineLength] chars separated by '\r\n'.
+   */
+  static String bytesToBase64(List<int> bytes, [int lineLength]) {
+    return _CryptoUtils.bytesToBase64(bytes, lineLength);
+  }
+}
+
+/**
+ * HashExceptions are thrown on invalid use of a Hash
+ * object.
+ */
+class HashException {
+  HashException(String this.message);
+  toString() => "HashException: $message";
+  String message;
+}
+