Expose some SHA1Digest methods for FIPS 186-2 PRF

The FIPS 186-2 PRF required by EAP-SIM and EAP-AKA (used in telephony)
require a hashing function extremely similar to SHA1, with the exception
of the padding bytes added. This commit exposes the BouncyCastle
SHA1Digest implementation as core-platform-api to allow platform
internals to implement FIPS 186-2 PRF without re-implementing SHA1.

Bug: 136175302
Test: Build succeeds, IKE using this, tests passing.
Change-Id: I2d61e2c331f3f80c8a1ebcb85209f9a49968ade5

2 files changed, 26 insertions, 19 deletions

diff --git a/repackaged/bcprov/src/main/java/com/android/org/bouncycastle/crypto/digests/GeneralDigest.java b/repackaged/bcprov/src/main/java/com/android/org/bouncycastle/crypto/digests/GeneralDigest.java
index c075dce5..80714665 100644
--- a/repackaged/bcprov/src/main/java/com/android/org/bouncycastle/crypto/digests/GeneralDigest.java
+++ b/repackaged/bcprov/src/main/java/com/android/org/bouncycastle/crypto/digests/GeneralDigest.java
@@ -10,6 +10,7 @@ import com.android.org.bouncycastle.util.Pack;
  * "Handbook of Applied Cryptography", pages 344 - 347.
  * @hide This class is not part of the Android public SDK API
  */
+@libcore.api.CorePlatformApi
 public abstract class GeneralDigest
     implements ExtendedDigest, Memoable
 {
@@ -67,6 +68,7 @@ public abstract class GeneralDigest
         byteCount++;
     }
 
+    @libcore.api.CorePlatformApi
     public void update(
         byte[]  in,
         int     inOff,
@@ -112,6 +114,7 @@ public abstract class GeneralDigest
         byteCount += len;
     }
 
+    @libcore.api.CorePlatformApi
     public void finish()
     {
         long    bitLength = (byteCount << 3);
@@ -153,10 +156,11 @@ public abstract class GeneralDigest
     {
         return BYTE_LENGTH;
     }
-    
+
     protected abstract void processWord(byte[] in, int inOff);
 
     protected abstract void processLength(long bitLength);
 
+    @libcore.api.CorePlatformApi
     protected abstract void processBlock();
 }
diff --git a/repackaged/bcprov/src/main/java/com/android/org/bouncycastle/crypto/digests/SHA1Digest.java b/repackaged/bcprov/src/main/java/com/android/org/bouncycastle/crypto/digests/SHA1Digest.java
index ebc5bfe4..a101d405 100644
--- a/repackaged/bcprov/src/main/java/com/android/org/bouncycastle/crypto/digests/SHA1Digest.java
+++ b/repackaged/bcprov/src/main/java/com/android/org/bouncycastle/crypto/digests/SHA1Digest.java
@@ -11,6 +11,7 @@ import com.android.org.bouncycastle.util.Pack;
  * is the "endianness" of the word processing!
  * @hide This class is not part of the Android public SDK API
  */
+@libcore.api.CorePlatformApi
 public class SHA1Digest
     extends GeneralDigest
     implements EncodableDigest
@@ -25,6 +26,7 @@ public class SHA1Digest
     /**
      * Standard constructor
      */
+    @libcore.api.CorePlatformApi
     public SHA1Digest()
     {
         reset();
@@ -100,7 +102,7 @@ public class SHA1Digest
         if (++xOff == 16)
         {
             processBlock();
-        }        
+        }
     }
 
     protected void processLength(
@@ -115,6 +117,7 @@ public class SHA1Digest
         X[15] = (int)bitLength;
     }
 
+    @libcore.api.CorePlatformApi
     public int doFinal(
         byte[]  out,
         int     outOff)
@@ -159,7 +162,7 @@ public class SHA1Digest
     private static final int    Y2 = 0x6ed9eba1;
     private static final int    Y3 = 0x8f1bbcdc;
     private static final int    Y4 = 0xca62c1d6;
-   
+
     private int f(
         int    u,
         int    v,
@@ -208,27 +211,27 @@ public class SHA1Digest
         // round 1
         //
         int idx = 0;
-        
+
         for (int j = 0; j < 4; j++)
         {
             // E = rotateLeft(A, 5) + f(B, C, D) + E + X[idx++] + Y1
             // B = rotateLeft(B, 30)
             E += (A << 5 | A >>> 27) + f(B, C, D) + X[idx++] + Y1;
             B = B << 30 | B >>> 2;
-        
+
             D += (E << 5 | E >>> 27) + f(A, B, C) + X[idx++] + Y1;
             A = A << 30 | A >>> 2;
-       
+
             C += (D << 5 | D >>> 27) + f(E, A, B) + X[idx++] + Y1;
             E = E << 30 | E >>> 2;
-       
+
             B += (C << 5 | C >>> 27) + f(D, E, A) + X[idx++] + Y1;
             D = D << 30 | D >>> 2;
 
             A += (B << 5 | B >>> 27) + f(C, D, E) + X[idx++] + Y1;
             C = C << 30 | C >>> 2;
         }
-        
+
         //
         // round 2
         //
@@ -237,21 +240,21 @@ public class SHA1Digest
             // E = rotateLeft(A, 5) + h(B, C, D) + E + X[idx++] + Y2
             // B = rotateLeft(B, 30)
             E += (A << 5 | A >>> 27) + h(B, C, D) + X[idx++] + Y2;
-            B = B << 30 | B >>> 2;   
-            
+            B = B << 30 | B >>> 2;
+
             D += (E << 5 | E >>> 27) + h(A, B, C) + X[idx++] + Y2;
             A = A << 30 | A >>> 2;
-            
+
             C += (D << 5 | D >>> 27) + h(E, A, B) + X[idx++] + Y2;
             E = E << 30 | E >>> 2;
-            
+
             B += (C << 5 | C >>> 27) + h(D, E, A) + X[idx++] + Y2;
             D = D << 30 | D >>> 2;
 
             A += (B << 5 | B >>> 27) + h(C, D, E) + X[idx++] + Y2;
             C = C << 30 | C >>> 2;
         }
-        
+
         //
         // round 3
         //
@@ -261,13 +264,13 @@ public class SHA1Digest
             // B = rotateLeft(B, 30)
             E += (A << 5 | A >>> 27) + g(B, C, D) + X[idx++] + Y3;
             B = B << 30 | B >>> 2;
-            
+
             D += (E << 5 | E >>> 27) + g(A, B, C) + X[idx++] + Y3;
             A = A << 30 | A >>> 2;
-            
+
             C += (D << 5 | D >>> 27) + g(E, A, B) + X[idx++] + Y3;
             E = E << 30 | E >>> 2;
-            
+
             B += (C << 5 | C >>> 27) + g(D, E, A) + X[idx++] + Y3;
             D = D << 30 | D >>> 2;
 
@@ -284,13 +287,13 @@ public class SHA1Digest
             // B = rotateLeft(B, 30)
             E += (A << 5 | A >>> 27) + h(B, C, D) + X[idx++] + Y4;
             B = B << 30 | B >>> 2;
-            
+
             D += (E << 5 | E >>> 27) + h(A, B, C) + X[idx++] + Y4;
             A = A << 30 | A >>> 2;
-            
+
             C += (D << 5 | D >>> 27) + h(E, A, B) + X[idx++] + Y4;
             E = E << 30 | E >>> 2;
-            
+
             B += (C << 5 | C >>> 27) + h(D, E, A) + X[idx++] + Y4;
             D = D << 30 | D >>> 2;