added exception check on UTF8 parsing to prevent escaping exceptions.

Author: dghgit

pg/src/main/java/org/bouncycastle/bcpg/ArmoredInputStream.java

@@ -268,7 +268,17 @@ private boolean parseHeaders()
                 }
                 if (c == '\r' || (last != '\r' && c == '\n'))
                 {
-                    String line = Strings.fromUTF8ByteArray(buf.toByteArray());
+                    String line;
+
+                    try
+                    {
+                        line = Strings.fromUTF8ByteArray(buf.toByteArray());
+                    }
+                    catch (Exception e)
+                    {
+                         throw new ArmoredInputException(e.getMessage());
+                    }
+
                     if (line.trim().length() == 0)
                     {
                         break;