#61162 - En-/decryption support for HWPF

Decryption for Binary RC4 and CryptoAPI (... XOR is missing)

git-svn-id: https://svn.apache.org/repos/asf/poi/trunk@1797837 13f79535-47bb-0310-9956-ffa450edef68

4 files changed, 21 insertions, 6 deletions

diff --git a/src/java/org/apache/poi/POIDocument.java b/src/java/org/apache/poi/POIDocument.java
index dc626da49b..774507722a 100644
--- a/src/java/org/apache/poi/POIDocument.java
+++ b/src/java/org/apache/poi/POIDocument.java
@@ -195,7 +195,7 @@ public abstract class POIDocument implements Closeable {
         NPOIFSFileSystem encPoifs = null;
         String step = "getting";
         try {
-            if (encryptionInfo != null) {
+            if (encryptionInfo != null && encryptionInfo.isDocPropsEncrypted()) {
                 step = "getting encrypted";
                 String encryptedStream = null;
                 for (String s : encryptedStreamNames) {
diff --git a/src/java/org/apache/poi/hssf/record/crypto/Biff8EncryptionKey.java b/src/java/org/apache/poi/hssf/record/crypto/Biff8EncryptionKey.java
index 382ae2f130..f589f02cb9 100644
--- a/src/java/org/apache/poi/hssf/record/crypto/Biff8EncryptionKey.java
+++ b/src/java/org/apache/poi/hssf/record/crypto/Biff8EncryptionKey.java
@@ -32,7 +32,11 @@ public final class Biff8EncryptionKey {
 	 * @param password pass <code>null</code> to clear user password (and use default)
 	 */
 	public static void setCurrentUserPassword(String password) {
-		_userPasswordTLS.set(password);
+	    if (password == null) {
+	        _userPasswordTLS.remove();
+	    } else {
+	        _userPasswordTLS.set(password);
+	    }
 	}
 
 	/**
diff --git a/src/java/org/apache/poi/poifs/crypt/EncryptionInfo.java b/src/java/org/apache/poi/poifs/crypt/EncryptionInfo.java
index e8895c1abf..c70105fb93 100644
--- a/src/java/org/apache/poi/poifs/crypt/EncryptionInfo.java
+++ b/src/java/org/apache/poi/poifs/crypt/EncryptionInfo.java
@@ -122,8 +122,11 @@ public class EncryptionInfo implements Cloneable {
         } else if (
                2 <= versionMajor && versionMajor <= 4
             && versionMinor == 2) {
-            encryptionMode = (preferredEncryptionMode == cryptoAPI) ? cryptoAPI : standard;
             encryptionFlags = dis.readInt();
+            encryptionMode = (
+                preferredEncryptionMode == cryptoAPI
+                || !flagAES.isSet(encryptionFlags))
+                ? cryptoAPI : standard;
         } else if (
                versionMajor == agile.versionMajor
             && versionMinor == agile.versionMinor){
@@ -268,6 +271,14 @@ public class EncryptionInfo implements Cloneable {
         return encryptionMode;
     }
     
+    /**
+     * @return true, if Document Summary / Summary are encrypted and stored in the {@code EncryptedStream} stream,
+     * otherwise the Summaries aren't encrypted and located in their usual streams
+     */
+    public boolean isDocPropsEncrypted() {
+        return !flagDocProps.isSet(getEncryptionFlags());
+    }
+    
     @Override
     public EncryptionInfo clone() throws CloneNotSupportedException {
         EncryptionInfo other = (EncryptionInfo)super.clone();
diff --git a/src/java/org/apache/poi/poifs/crypt/binaryrc4/BinaryRC4Decryptor.java b/src/java/org/apache/poi/poifs/crypt/binaryrc4/BinaryRC4Decryptor.java
index 1cc6b1b2f4..8be9ab3faa 100644
--- a/src/java/org/apache/poi/poifs/crypt/binaryrc4/BinaryRC4Decryptor.java
+++ b/src/java/org/apache/poi/poifs/crypt/binaryrc4/BinaryRC4Decryptor.java
@@ -51,9 +51,9 @@ public class BinaryRC4Decryptor extends Decryptor implements Cloneable {
             super(stream, size, chunkSize);
         }
 
-        public BinaryRC4CipherInputStream(InputStream stream)
+        public BinaryRC4CipherInputStream(InputStream stream, int size, int initialPos)
                 throws GeneralSecurityException {
-            super(stream, Integer.MAX_VALUE, chunkSize);
+            super(stream, size, chunkSize, initialPos);
         }    
     }
 
@@ -141,7 +141,7 @@ public class BinaryRC4Decryptor extends Decryptor implements Cloneable {
     @Override
     public InputStream getDataStream(InputStream stream, int size, int initialPos)
             throws IOException, GeneralSecurityException {
-        return new BinaryRC4CipherInputStream(stream);
+        return new BinaryRC4CipherInputStream(stream, size, initialPos);
     }