1 files changed, 98 insertions, 0 deletions
diff --git a/misc/cms/cms_comp.cpp b/misc/cms/cms_comp.cpp
new file mode 100644
index 000000000..8d120c172
--- /dev/null
+++ b/misc/cms/cms_comp.cpp
@@ -0,0 +1,98 @@
+/*************************************************
+* CMS Compression Source File                    *
+* (C) 1999-2003 The Botan Project                *
+*************************************************/
+
+#include <botan/cms_enc.h>
+#include <botan/cms_dec.h>
+#include <botan/der_enc.h>
+#include <botan/ber_dec.h>
+#include <botan/oids.h>
+#include <botan/pipe.h>
+
+#if defined(BOTAN_EXT_COMPRESSOR_ZLIB)
+  #include <botan/zlib.h>
+  #define HAVE_ZLIB 1
+#else
+  #define HAVE_ZLIB 0
+#endif
+
+namespace Botan {
+
+/*************************************************
+* Compress a message                             *
+*************************************************/
+void CMS_Encoder::compress(const std::string& algo)
+   {
+   if(!CMS_Encoder::can_compress_with(algo))
+      throw Invalid_Argument("CMS_Encoder: Cannot compress with " + algo);
+
+   Filter* compressor = 0;
+
+#if HAVE_ZLIB
+   if(algo == "Zlib") compressor = new Zlib_Compression;
+#endif
+
+   if(compressor == 0)
+      throw Internal_Error("CMS: Couldn't get ahold of a compressor");
+
+   Pipe pipe(compressor);
+   pipe.process_msg(data);
+   SecureVector<byte> compressed = pipe.read_all();
+
+   DER_Encoder encoder;
+   encoder.start_sequence();
+     DER::encode(encoder, 0);
+     DER::encode(encoder, AlgorithmIdentifier("Compression." + algo, false));
+     encoder.add_raw_octets(make_econtent(compressed, type));
+   encoder.end_sequence();
+
+   add_layer("CMS.CompressedData", encoder);
+   }
+
+/*************************************************
+* See if the named compression algo is available *
+*************************************************/
+bool CMS_Encoder::can_compress_with(const std::string& algo)
+   {
+   if(HAVE_ZLIB && algo == "Zlib")
+      return true;
+   return false;
+   }
+
+/*************************************************
+* Decompress a message                           *
+*************************************************/
+void CMS_Decoder::decompress(BER_Decoder& decoder)
+   {
+   u32bit version;
+   AlgorithmIdentifier comp_algo;
+
+   BER_Decoder comp_info = BER::get_subsequence(decoder);
+   BER::decode(comp_info, version);
+   if(version != 0)
+      throw Decoding_Error("CMS: Unknown version for CompressedData");
+   BER::decode(comp_info, comp_algo);
+   read_econtent(comp_info);
+   comp_info.verify_end();
+
+   Filter* decompressor = 0;
+
+   info = comp_algo.oid.as_string();
+#if HAVE_ZLIB
+   if(comp_algo.oid == OIDS::lookup("Compression.Zlib"))
+      {
+      decompressor = new Zlib_Decompression;
+      info = "Zlib";
+      }
+#endif
+
+   if(!decompressor)
+      status = FAILURE;
+
+   Pipe pipe(decompressor);
+   pipe.process_msg(data);
+   data = pipe.read_all();
+   }
+
+}