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author | Roberto Tyley <roberto.tyley@gmail.com> | 2014-07-15 01:38:01 +0400 |
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committer | Roberto Tyley <roberto.tyley@gmail.com> | 2014-07-26 11:23:17 +0400 |
commit | 7cb752aaf746dc0b473afeb9e892b7fbc12666c5 (patch) | |
tree | cc4f91ddc18332b5adbe82e3fcb040d976c90105 /core/src/main/java/org/spongycastle/math/ec/AbstractECMultiplier.java | |
parent | 551830f8ea5177042af2c7dd1fc90888bc67387d (diff) |
Execute become-spongy.sh
https://github.com/rtyley/spongycastle/blob/3040af/become-spongy.sh
Diffstat (limited to 'core/src/main/java/org/spongycastle/math/ec/AbstractECMultiplier.java')
-rw-r--r-- | core/src/main/java/org/spongycastle/math/ec/AbstractECMultiplier.java | 26 |
1 files changed, 26 insertions, 0 deletions
diff --git a/core/src/main/java/org/spongycastle/math/ec/AbstractECMultiplier.java b/core/src/main/java/org/spongycastle/math/ec/AbstractECMultiplier.java new file mode 100644 index 00000000..e4dee6dd --- /dev/null +++ b/core/src/main/java/org/spongycastle/math/ec/AbstractECMultiplier.java @@ -0,0 +1,26 @@ +package org.spongycastle.math.ec; + +import java.math.BigInteger; + +public abstract class AbstractECMultiplier implements ECMultiplier +{ + public ECPoint multiply(ECPoint p, BigInteger k) + { + int sign = k.signum(); + if (sign == 0 || p.isInfinity()) + { + return p.getCurve().getInfinity(); + } + + ECPoint positive = multiplyPositive(p, k.abs()); + ECPoint result = sign > 0 ? positive : positive.negate(); + + /* + * Although the various multipliers ought not to produce invalid output under normal + * circumstances, a final check here is advised to guard against fault attacks. + */ + return ECAlgorithms.validatePoint(result); + } + + protected abstract ECPoint multiplyPositive(ECPoint p, BigInteger k); +} |