another blind sha2 bug fix ...

git-svn-id: https://svn.apache.org/repos/asf/poi/trunk@1637005 13f79535-47bb-0310-9956-ffa450edef68

src/ooxml/java/org/apache/poi/poifs/crypt/dsig/SignatureInfo.java

@@ -241,6 +241,8 @@ public class SignatureInfo implements SignatureConfigurable {
                 }
                 
                 return valid;
+            } catch (ArrayIndexOutOfBoundsException e) {
+                throw new JvmBrokenException(e);
             } catch (Exception e) {
                 LOG.log(POILogger.ERROR, "error in marshalling and validating the signature", e);
                 return false;
@@ -538,7 +540,7 @@ public class SignatureInfo implements SignatureConfigurable {
             String description = signatureConfig.getSignatureDescription();
             return new DigestInfo(digestValue, signatureConfig.getDigestAlgo(), description);
         } catch (ArrayIndexOutOfBoundsException e) {
-            throw new EncryptedDocumentException("\"your JVM is just too broken\" - check https://bugzilla.redhat.com/show_bug.cgi?id=1155012 if this applies to the stacktrace ...", e);
+            throw new JvmBrokenException(e);
         }
     }
 
@@ -649,4 +651,10 @@ public class SignatureInfo implements SignatureConfigurable {
     private static <T> List<T> safe(List<T> other) {
         return other == null ? Collections.EMPTY_LIST : other;
     }
+    
+    private static class JvmBrokenException extends EncryptedDocumentException {
+        public JvmBrokenException(Throwable cause) {
+            super("\"your JVM is just too broken\" - check https://bugzilla.redhat.com/show_bug.cgi?id=1155012 if this applies to the stacktrace ...", cause);
+        }
+    }
 }