diff options
Diffstat (limited to 'src/main/java/ch/ethz/ssh2/crypto/digest/HMAC.java')
-rw-r--r-- | src/main/java/ch/ethz/ssh2/crypto/digest/HMAC.java | 98 |
1 files changed, 98 insertions, 0 deletions
diff --git a/src/main/java/ch/ethz/ssh2/crypto/digest/HMAC.java b/src/main/java/ch/ethz/ssh2/crypto/digest/HMAC.java new file mode 100644 index 0000000..fcdf43d --- /dev/null +++ b/src/main/java/ch/ethz/ssh2/crypto/digest/HMAC.java @@ -0,0 +1,98 @@ +/* + * Copyright (c) 2006-2011 Christian Plattner. All rights reserved. + * Please refer to the LICENSE.txt for licensing details. + */ +package ch.ethz.ssh2.crypto.digest; + +/** + * HMAC. + * + * @author Christian Plattner + * @version 2.50, 03/15/10 + */ +public final class HMAC implements Digest +{ + Digest md; + byte[] k_xor_ipad; + byte[] k_xor_opad; + + byte[] tmp; + + int size; + + public HMAC(Digest md, byte[] key, int size) + { + this.md = md; + this.size = size; + + tmp = new byte[md.getDigestLength()]; + + int blocksize = 64; + + k_xor_ipad = new byte[blocksize]; + k_xor_opad = new byte[blocksize]; + + if (key.length > blocksize) + { + md.reset(); + md.update(key); + md.digest(tmp); + key = tmp; + } + + System.arraycopy(key, 0, k_xor_ipad, 0, key.length); + System.arraycopy(key, 0, k_xor_opad, 0, key.length); + + for (int i = 0; i < blocksize; i++) + { + k_xor_ipad[i] ^= 0x36; + k_xor_opad[i] ^= 0x5C; + } + md.update(k_xor_ipad); + } + + public int getDigestLength() + { + return size; + } + + public void update(byte b) + { + md.update(b); + } + + public void update(byte[] b) + { + md.update(b); + } + + public void update(byte[] b, int off, int len) + { + md.update(b, off, len); + } + + public void reset() + { + md.reset(); + md.update(k_xor_ipad); + } + + public void digest(byte[] out) + { + digest(out, 0); + } + + public void digest(byte[] out, int off) + { + md.digest(tmp); + + md.update(k_xor_opad); + md.update(tmp); + + md.digest(tmp); + + System.arraycopy(tmp, 0, out, off, size); + + md.update(k_xor_ipad); + } +} |