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Diffstat (limited to 'libraries/spongycastle/jce/src/main/java/javax/crypto/spec/RC5ParameterSpec.java')
| -rw-r--r-- | libraries/spongycastle/jce/src/main/java/javax/crypto/spec/RC5ParameterSpec.java | 224 |
1 files changed, 224 insertions, 0 deletions
diff --git a/libraries/spongycastle/jce/src/main/java/javax/crypto/spec/RC5ParameterSpec.java b/libraries/spongycastle/jce/src/main/java/javax/crypto/spec/RC5ParameterSpec.java new file mode 100644 index 000000000..a34c645b4 --- /dev/null +++ b/libraries/spongycastle/jce/src/main/java/javax/crypto/spec/RC5ParameterSpec.java @@ -0,0 +1,224 @@ +package javax.crypto.spec; + +import java.security.spec.AlgorithmParameterSpec; + +/** + * This class specifies the parameters used with the + * <a href="http://www.rsa.com/rsalabs/newfaq/q76.html"><i>RC5</i></a> + * algorithm. + * <p> + * The parameters consist of a version number, a rounds count, a word + * size, and optionally an initialization vector (IV) (only in feedback mode). + * <p> + * This class can be used to initialize a <code>Cipher</code> object that + * implements the <i>RC5</i> algorithm as supplied by + * <a href="http://www.rsa.com">RSA Data Security, Inc.</a> (RSA DSI), + * or any parties authorized by RSA DSI. + */ +public class RC5ParameterSpec + implements AlgorithmParameterSpec +{ + private int version; + private int rounds; + private int wordSize; + + private byte[] iv; + + /** + * Constructs a parameter set for RC5 from the given version, number of + * rounds and word size (in bits). + * + * @param version the version. + * @param rounds the number of rounds. + * @param wordSize the word size in bits. + */ + public RC5ParameterSpec( + int version, + int rounds, + int wordSize) + { + this.version = version; + this.rounds = rounds; + this.wordSize = wordSize; + this.iv = null; + } + + /** + * Constructs a parameter set for RC5 from the given version, number of + * rounds, word size (in bits), and IV. + * <p> + * Note that the size of the IV (block size) must be twice the word + * size. The bytes that constitute the IV are those between + * <code>iv[0]</code> and <code>iv[2*(wordSize/8)-1]</code> inclusive. + * + * @param version the version. + * @param rounds the number of rounds. + * @param wordSize the word size in bits. + * @param iv the buffer with the IV. + */ + public RC5ParameterSpec( + int version, + int rounds, + int wordSize, + byte[] iv) + { + this(version, rounds, wordSize, iv, 0); + } + + /** + * Constructs a parameter set for RC5 from the given version, number of + * rounds, word size (in bits), and IV. + * <p> + * The IV is taken from <code>iv</code>, starting at <code>offset</code> inclusive. + * Note that the size of the IV (block size), starting at + * <code>offset</code> inclusive, must be twice the word size. + * The bytes that constitute the IV are those between + * <code>iv[offset]</code> and <code>iv[offset+2*(wordSize/8)-1]</code> + * inclusive. + * + * @param version the version. + * @param rounds the number of rounds. + * @param wordSize the word size in bits. + * @param iv the buffer with the IV. + * @param offset the offset in <code>iv</code> where the IV starts. + */ + public RC5ParameterSpec( + int version, + int rounds, + int wordSize, + byte[] iv, + int offset) + { + this.version = version; + this.rounds = rounds; + this.wordSize = wordSize; + this.iv = new byte[2 * (wordSize / 8)]; + + System.arraycopy(iv, offset, this.iv, 0, this.iv.length); + } + + /** + * Returns the version. + * + * @return the version. + */ + public int getVersion() + { + return version; + } + + /** + * Returns the number of rounds. + * + * @return the number of rounds. + */ + public int getRounds() + { + return rounds; + } + + /** + * Returns the word size in bits + * + * @return the word size in bits. + */ + public int getWordSize() + { + return wordSize; + } + + /** + * Returns the IV or null if this parameter set does not contain an IV. + * + * @return the IV or null if this parameter set does not contain an IV. + */ + public byte[] getIV() + { + if (iv == null) + { + return null; + } + + byte[] tmp = new byte[iv.length]; + + System.arraycopy(iv, 0, tmp, 0, iv.length); + + return tmp; + } + + /** + * Tests for equality between the specified object and this + * object. Two RC5ParameterSpec objects are considered equal if their + * version numbers, number of rounds, word sizes, and IVs are equal. + * (Two IV references are considered equal if both are <tt>null</tt>.) + * + * @param obj the object to test for equality with this object. + * @return true if the objects are considered equal, false otherwise. + */ + public boolean equals( + Object obj) + { + if ((obj == null) || !(obj instanceof RC5ParameterSpec)) + { + return false; + } + + RC5ParameterSpec spec = (RC5ParameterSpec)obj; + + if (this.version != spec.version) + { + return false; + } + + if (this.rounds != spec.rounds) + { + return false; + } + + if (this.wordSize != spec.wordSize) + { + return false; + } + + if (iv != null) + { + if (spec.iv == null || spec.iv.length != iv.length) + { + return false; + } + + for (int i = 0; i != iv.length; i++) + { + if (iv[i] != spec.iv[i]) + { + return false; + } + } + } + else if (spec.iv != null) + { + return false; + } + + return true; + } + + /** + * Calculates a hash code value for the object. + * Objects that are equal will also have the same hashcode. + */ + public int hashCode() + { + int code = version ^ rounds ^ wordSize; + + if (iv != null) + { + for (int i = 0; i != iv.length; i++) + { + code ^= iv[i] << (8 * (i % 4)); + } + } + + return code; + } +} |