diff options
author | Sergio Giro <sgiro@google.com> | 2016-02-01 18:52:42 +0000 |
---|---|---|
committer | Gerrit Code Review <noreply-gerritcodereview@google.com> | 2016-02-01 18:52:42 +0000 |
commit | 9218edabd1ef9852bc2f13115dcadc81b442dd6c (patch) | |
tree | 8229ff72c8cbb06f49dce3a8382930919fa6fc2b /bcprov/src/main/java/org/bouncycastle/crypto/modes/gcm/BasicGCMExponentiator.java | |
parent | 9b30eb05e5be69d51881a0d1b31e503e97acd784 (diff) | |
parent | 397d32894b89b506dc318e0f83446187c9b76ebe (diff) | |
download | android_external_bouncycastle-9218edabd1ef9852bc2f13115dcadc81b442dd6c.tar.gz android_external_bouncycastle-9218edabd1ef9852bc2f13115dcadc81b442dd6c.tar.bz2 android_external_bouncycastle-9218edabd1ef9852bc2f13115dcadc81b442dd6c.zip |
Merge "Merge remote-tracking branch 'aosp/upstream-master' into merge-152-from-upstream"
Diffstat (limited to 'bcprov/src/main/java/org/bouncycastle/crypto/modes/gcm/BasicGCMExponentiator.java')
-rw-r--r-- | bcprov/src/main/java/org/bouncycastle/crypto/modes/gcm/BasicGCMExponentiator.java | 36 |
1 files changed, 36 insertions, 0 deletions
diff --git a/bcprov/src/main/java/org/bouncycastle/crypto/modes/gcm/BasicGCMExponentiator.java b/bcprov/src/main/java/org/bouncycastle/crypto/modes/gcm/BasicGCMExponentiator.java new file mode 100644 index 0000000..fc25810 --- /dev/null +++ b/bcprov/src/main/java/org/bouncycastle/crypto/modes/gcm/BasicGCMExponentiator.java @@ -0,0 +1,36 @@ +package org.bouncycastle.crypto.modes.gcm; + +import org.bouncycastle.util.Arrays; + +public class BasicGCMExponentiator implements GCMExponentiator +{ + private int[] x; + + public void init(byte[] x) + { + this.x = GCMUtil.asInts(x); + } + + public void exponentiateX(long pow, byte[] output) + { + // Initial value is little-endian 1 + int[] y = GCMUtil.oneAsInts(); + + if (pow > 0) + { + int[] powX = Arrays.clone(x); + do + { + if ((pow & 1L) != 0) + { + GCMUtil.multiply(y, powX); + } + GCMUtil.multiply(powX, powX); + pow >>>= 1; + } + while (pow > 0); + } + + GCMUtil.asBytes(y, output); + } +} |