Index precomputation info by name

5 files changed, 36 insertions, 14 deletions

diff --git a/crypto/src/math/ec/ECCurve.cs b/crypto/src/math/ec/ECCurve.cs
index 82cf1367b..5c7592a92 100644
--- a/crypto/src/math/ec/ECCurve.cs
+++ b/crypto/src/math/ec/ECCurve.cs
@@ -116,26 +116,40 @@ namespace Org.BouncyCastle.Math.EC
             return coord == COORD_AFFINE;
         }
 
-        public virtual PreCompInfo GetPreCompInfo(ECPoint p)
+        public virtual PreCompInfo GetPreCompInfo(ECPoint point, string name)
         {
-            CheckPoint(p);
-            return p.m_preCompInfo;
+            CheckPoint(point);
+            lock (point)
+            {
+                IDictionary table = point.m_preCompTable;
+                return table == null ? null : (PreCompInfo)table[name];
+            }
         }
 
         /**
-         * Sets the <code>PreCompInfo</code> for a point on this curve. Used by
+         * Adds <code>PreCompInfo</code> for a point on this curve, under a given name. Used by
          * <code>ECMultiplier</code>s to save the precomputation for this <code>ECPoint</code> for use
          * by subsequent multiplication.
          * 
          * @param point
          *            The <code>ECPoint</code> to store precomputations for.
+         * @param name
+         *            A <code>String</code> used to index precomputations of different types.
          * @param preCompInfo
          *            The values precomputed by the <code>ECMultiplier</code>.
          */
-        public virtual void SetPreCompInfo(ECPoint point, PreCompInfo preCompInfo)
+        public virtual void SetPreCompInfo(ECPoint point, string name, PreCompInfo preCompInfo)
         {
             CheckPoint(point);
-            point.m_preCompInfo = preCompInfo;
+            lock (point)
+            {
+                IDictionary table = point.m_preCompTable;
+                if (null == table)
+                {
+                    point.m_preCompTable = table = Platform.CreateHashtable(4);
+                }
+                table[name] = preCompInfo;
+            }
         }
 
         public virtual ECPoint ImportPoint(ECPoint p)
diff --git a/crypto/src/math/ec/ECPoint.cs b/crypto/src/math/ec/ECPoint.cs
index 4b6a2cbce..f8bbf04e7 100644
--- a/crypto/src/math/ec/ECPoint.cs
+++ b/crypto/src/math/ec/ECPoint.cs
@@ -50,7 +50,8 @@ namespace Org.BouncyCastle.Math.EC
         protected internal readonly ECFieldElement[] m_zs;
         protected internal readonly bool m_withCompression;
 
-        protected internal PreCompInfo m_preCompInfo = null;
+        // Dictionary is (string -> PreCompInfo)
+        protected internal IDictionary m_preCompTable = null;
 
         protected ECPoint(ECCurve curve, ECFieldElement	x, ECFieldElement y, bool withCompression)
             : this(curve, x, y, GetInitialZCoords(curve), withCompression)
diff --git a/crypto/src/math/ec/multiplier/FixedPointUtilities.cs b/crypto/src/math/ec/multiplier/FixedPointUtilities.cs
index 8a04fcdc1..194995e08 100644
--- a/crypto/src/math/ec/multiplier/FixedPointUtilities.cs
+++ b/crypto/src/math/ec/multiplier/FixedPointUtilities.cs
@@ -4,6 +4,8 @@ namespace Org.BouncyCastle.Math.EC.Multiplier
 {
     public class FixedPointUtilities
     {
+        public static readonly string PRECOMP_NAME = "bc_fixed_point";
+
         public static int GetCombSize(ECCurve c)
         {
             BigInteger order = c.Order;
@@ -25,7 +27,7 @@ namespace Org.BouncyCastle.Math.EC.Multiplier
             ECCurve c = p.Curve;
 
             int n = 1 << width;
-            FixedPointPreCompInfo info = GetFixedPointPreCompInfo(c.GetPreCompInfo(p));
+            FixedPointPreCompInfo info = GetFixedPointPreCompInfo(c.GetPreCompInfo(p, PRECOMP_NAME));
             ECPoint[] lookupTable = info.PreComp;
 
             if (lookupTable == null || lookupTable.Length != n)
@@ -60,7 +62,7 @@ namespace Org.BouncyCastle.Math.EC.Multiplier
 
                 info.PreComp = lookupTable;
 
-                c.SetPreCompInfo(p, info);
+                c.SetPreCompInfo(p, PRECOMP_NAME, info);
             }
 
             return info;
diff --git a/crypto/src/math/ec/multiplier/WNafUtilities.cs b/crypto/src/math/ec/multiplier/WNafUtilities.cs
index d37da8a5e..eac47222b 100644
--- a/crypto/src/math/ec/multiplier/WNafUtilities.cs
+++ b/crypto/src/math/ec/multiplier/WNafUtilities.cs
@@ -4,6 +4,8 @@ namespace Org.BouncyCastle.Math.EC.Multiplier
 {
     public abstract class WNafUtilities
     {
+        public static readonly string PRECOMP_NAME = "bc_wnaf";
+
         private static int[] DEFAULT_WINDOW_SIZE_CUTOFFS = new int[]{ 13, 41, 121, 337, 897, 2305 };
 
         public static int[] GenerateCompactNaf(BigInteger k)
@@ -188,7 +190,7 @@ namespace Org.BouncyCastle.Math.EC.Multiplier
          * most one is non-zero.
          * @param k The integer of which the Window NAF is computed.
          * @return The Window NAF of the given width, such that the following holds:
-         * <code>k = &sum;<sub>i=0</sub><sup>l-1</sup> k<sub>i</sub>2<sup>i</sup>
+         * <code>k = &amp;sum;<sub>i=0</sub><sup>l-1</sup> k<sub>i</sub>2<sup>i</sup>
          * </code>, where the <code>k<sub>i</sub></code> denote the elements of the
          * returned <code>byte[]</code>.
          */
@@ -292,7 +294,7 @@ namespace Org.BouncyCastle.Math.EC.Multiplier
         public static WNafPreCompInfo Precompute(ECPoint p, int width, bool includeNegated)
         {
             ECCurve c = p.Curve;
-            WNafPreCompInfo wnafPreCompInfo = GetWNafPreCompInfo(c.GetPreCompInfo(p));
+            WNafPreCompInfo wnafPreCompInfo = GetWNafPreCompInfo(c.GetPreCompInfo(p, PRECOMP_NAME));
             
             ECPoint[] preComp = wnafPreCompInfo.PreComp;
             if (preComp == null)
@@ -363,7 +365,7 @@ namespace Org.BouncyCastle.Math.EC.Multiplier
                 wnafPreCompInfo.PreCompNeg = preCompNeg;
             }
 
-            c.SetPreCompInfo(p, wnafPreCompInfo);
+            c.SetPreCompInfo(p, PRECOMP_NAME, wnafPreCompInfo);
 
             return wnafPreCompInfo;
         }
diff --git a/crypto/src/math/ec/multiplier/WTauNafMultiplier.cs b/crypto/src/math/ec/multiplier/WTauNafMultiplier.cs
index b87b87000..dda778eea 100644
--- a/crypto/src/math/ec/multiplier/WTauNafMultiplier.cs
+++ b/crypto/src/math/ec/multiplier/WTauNafMultiplier.cs
@@ -11,6 +11,9 @@ namespace Org.BouncyCastle.Math.EC.Multiplier
     public class WTauNafMultiplier
         : AbstractECMultiplier
     {
+        // TODO Create WTauNafUtilities class and move various functionality into it
+        internal static readonly string PRECOMP_NAME = "bc_wtnaf";
+
         /**
         * Multiplies a {@link org.bouncycastle.math.ec.F2mPoint F2mPoint}
         * by <code>k</code> using the reduced <code>&#964;</code>-adic NAF (RTNAF)
@@ -33,7 +36,7 @@ namespace Org.BouncyCastle.Math.EC.Multiplier
 
             ZTauElement rho = Tnaf.PartModReduction(k, m, a, s, mu, (sbyte)10);
 
-            return MultiplyWTnaf(p, rho, curve.GetPreCompInfo(p), a, mu);
+            return MultiplyWTnaf(p, rho, curve.GetPreCompInfo(p, PRECOMP_NAME), a, mu);
         }
 
         /**
@@ -80,7 +83,7 @@ namespace Org.BouncyCastle.Math.EC.Multiplier
 
                 WTauNafPreCompInfo pre = new WTauNafPreCompInfo();
                 pre.PreComp = pu;
-                curve.SetPreCompInfo(p, pre);
+                curve.SetPreCompInfo(p, PRECOMP_NAME, pre);
             }
             else
             {