1 files changed, 102 insertions, 0 deletions
diff --git a/core/src/main/java/org/spongycastle/asn1/BEROctetStringGenerator.java b/core/src/main/java/org/spongycastle/asn1/BEROctetStringGenerator.java
new file mode 100644
index 00000000..47d1a0eb
--- /dev/null
+++ b/core/src/main/java/org/spongycastle/asn1/BEROctetStringGenerator.java
@@ -0,0 +1,102 @@
+package org.spongycastle.asn1;
+
+import java.io.IOException;
+import java.io.OutputStream;
+
+public class BEROctetStringGenerator
+    extends BERGenerator
+{
+    public BEROctetStringGenerator(OutputStream out) 
+        throws IOException
+    {
+        super(out);
+        
+        writeBERHeader(BERTags.CONSTRUCTED | BERTags.OCTET_STRING);
+    }
+
+    public BEROctetStringGenerator(
+        OutputStream out,
+        int tagNo,
+        boolean isExplicit) 
+        throws IOException
+    {
+        super(out, tagNo, isExplicit);
+        
+        writeBERHeader(BERTags.CONSTRUCTED | BERTags.OCTET_STRING);
+    }
+    
+    public OutputStream getOctetOutputStream()
+    {
+        return getOctetOutputStream(new byte[1000]); // limit for CER encoding.
+    }
+
+    public OutputStream getOctetOutputStream(
+        byte[] buf)
+    {
+        return new BufferedBEROctetStream(buf);
+    }
+   
+    private class BufferedBEROctetStream
+        extends OutputStream
+    {
+        private byte[] _buf;
+        private int    _off;
+        private DEROutputStream _derOut;
+
+        BufferedBEROctetStream(
+            byte[] buf)
+        {
+            _buf = buf;
+            _off = 0;
+            _derOut = new DEROutputStream(_out);
+        }
+        
+        public void write(
+            int b)
+            throws IOException
+        {
+            _buf[_off++] = (byte)b;
+
+            if (_off == _buf.length)
+            {
+                DEROctetString.encode(_derOut, _buf);
+                _off = 0;
+            }
+        }
+
+        public void write(byte[] b, int off, int len) throws IOException
+        {
+            while (len > 0)
+            {
+                int numToCopy = Math.min(len, _buf.length - _off);
+                System.arraycopy(b, off, _buf, _off, numToCopy);
+
+                _off += numToCopy;
+                if (_off < _buf.length)
+                {
+                    break;
+                }
+
+                DEROctetString.encode(_derOut, _buf);
+                _off = 0;
+
+                off += numToCopy;
+                len -= numToCopy;
+            }
+        }
+
+        public void close() 
+            throws IOException
+        {
+            if (_off != 0)
+            {
+                byte[] bytes = new byte[_off];
+                System.arraycopy(_buf, 0, bytes, 0, _off);
+                
+                DEROctetString.encode(_derOut, bytes);
+            }
+            
+             writeBEREnd();
+        }
+    }
+}