From 52748cd5cf48d3c68c3b912305fafaf9978138a6 Mon Sep 17 00:00:00 2001
From: Boris Wachtmeister <boris-code@gmx.com>
Date: Sun, 11 Jan 2015 20:35:56 +0100
Subject: [PATCH] bugfix: BaseMac would not use bsize in certain cases

The implementation of BaseMac would only take the bsize (size of the
hash) into account if the #doFinal(byte[] input) method was called.
Both other #doFinal methods would behave as if bsize==defbsize and
not cut the hash to the right size.
---
 .../net/schmizz/sshj/transport/mac/BaseMAC.java     | 13 +++++++++++--
 .../schmizz/sshj/transport/mac/HMACMD596Test.java   |  2 --
 .../schmizz/sshj/transport/mac/HMACSHA196Test.java  |  2 --
 3 files changed, 11 insertions(+), 6 deletions(-)

diff --git a/src/main/java/net/schmizz/sshj/transport/mac/BaseMAC.java b/src/main/java/net/schmizz/sshj/transport/mac/BaseMAC.java
index b9b1da782..6019b4df2 100644
--- a/src/main/java/net/schmizz/sshj/transport/mac/BaseMAC.java
+++ b/src/main/java/net/schmizz/sshj/transport/mac/BaseMAC.java
@@ -41,12 +41,12 @@ public BaseMAC(String algorithm, int bsize, int defbsize) {
 
     @Override
     public byte[] doFinal() {
-        return mac.doFinal();
+        return resizeToHashSize(mac.doFinal());
     }
 
     @Override
     public byte[] doFinal(byte[] input) {
-        return mac.doFinal(input);
+        return resizeToHashSize(mac.doFinal(input));
     }
 
     @Override
@@ -62,6 +62,15 @@ public void doFinal(byte[] buf, int offset) {
         }
     }
 
+    private byte[] resizeToHashSize(byte[] buf) {
+        if (bsize == defbsize)
+            return buf;
+
+        byte[] result = new byte[bsize];
+        System.arraycopy(buf, 0, result, 0, bsize);
+        return result;
+    }
+
     @Override
     public int getBlockSize() {
         return bsize;
diff --git a/src/test/java/net/schmizz/sshj/transport/mac/HMACMD596Test.java b/src/test/java/net/schmizz/sshj/transport/mac/HMACMD596Test.java
index 0a91b4fa6..82204a8a9 100644
--- a/src/test/java/net/schmizz/sshj/transport/mac/HMACMD596Test.java
+++ b/src/test/java/net/schmizz/sshj/transport/mac/HMACMD596Test.java
@@ -15,7 +15,6 @@ public class HMACMD596Test {
     private static final String EXPECTED_HMAC = "dff33c507463f9cf088a5ce8";
 
     @Test
-    @Ignore
     public void testUpdateWithDoFinal() {
         HMACMD596 hmac = initHmac();
         hmac.update(PLAIN_TEXT);
@@ -23,7 +22,6 @@ public void testUpdateWithDoFinal() {
     }
 
     @Test
-    @Ignore
     public void testDoFinalWithInput() {
         HMACMD596 hmac = initHmac();
         assertThat(Hex.toHexString(hmac.doFinal(PLAIN_TEXT)),
diff --git a/src/test/java/net/schmizz/sshj/transport/mac/HMACSHA196Test.java b/src/test/java/net/schmizz/sshj/transport/mac/HMACSHA196Test.java
index 0c4d04947..26f7d995f 100644
--- a/src/test/java/net/schmizz/sshj/transport/mac/HMACSHA196Test.java
+++ b/src/test/java/net/schmizz/sshj/transport/mac/HMACSHA196Test.java
@@ -15,7 +15,6 @@ public class HMACSHA196Test {
     private static final String EXPECTED_HMAC = "24ddeed57ad91465c5b59dce";
 
     @Test
-    @Ignore
     public void testUpdateWithDoFinal() {
         HMACSHA196 hmac = initHmac();
         hmac.update(PLAIN_TEXT);
@@ -23,7 +22,6 @@ public void testUpdateWithDoFinal() {
     }
 
     @Test
-    @Ignore
     public void testDoFinalWithInput() {
         HMACSHA196 hmac = initHmac();
         assertThat(Hex.toHexString(hmac.doFinal(PLAIN_TEXT)), is(EXPECTED_HMAC));