1 files changed, 103 insertions, 0 deletions
diff --git a/src/lib/modes/mode_pad/mode_pad.cpp b/src/lib/modes/mode_pad/mode_pad.cpp
new file mode 100644
index 000000000..918964c74
--- /dev/null
+++ b/src/lib/modes/mode_pad/mode_pad.cpp
@@ -0,0 +1,103 @@
+/*
+* CBC Padding Methods
+* (C) 1999-2007,2013 Jack Lloyd
+*
+* Distributed under the terms of the Botan license
+*/
+
+#include <botan/mode_pad.h>
+#include <botan/exceptn.h>
+
+namespace Botan {
+
+/*
+* Pad with PKCS #7 Method
+*/
+void PKCS7_Padding::add_padding(secure_vector<byte>& buffer,
+                                size_t last_byte_pos,
+                                size_t block_size) const
+   {
+   const byte pad_value = block_size - last_byte_pos;
+
+   for(size_t i = 0; i != pad_value; ++i)
+      buffer.push_back(pad_value);
+   }
+
+/*
+* Unpad with PKCS #7 Method
+*/
+size_t PKCS7_Padding::unpad(const byte block[], size_t size) const
+   {
+   size_t position = block[size-1];
+
+   if(position > size)
+      throw Decoding_Error("Bad padding in " + name());
+
+   for(size_t j = size-position; j != size-1; ++j)
+      if(block[j] != position)
+         throw Decoding_Error("Bad padding in " + name());
+
+   return (size-position);
+   }
+
+/*
+* Pad with ANSI X9.23 Method
+*/
+void ANSI_X923_Padding::add_padding(secure_vector<byte>& buffer,
+                                    size_t last_byte_pos,
+                                    size_t block_size) const
+   {
+   const byte pad_value = block_size - last_byte_pos;
+
+   for(size_t i = last_byte_pos; i < block_size; ++i)
+      buffer.push_back(0);
+   buffer.push_back(pad_value);
+   }
+
+/*
+* Unpad with ANSI X9.23 Method
+*/
+size_t ANSI_X923_Padding::unpad(const byte block[], size_t size) const
+   {
+   size_t position = block[size-1];
+   if(position > size)
+      throw Decoding_Error(name());
+   for(size_t j = size-position; j != size-1; ++j)
+      if(block[j] != 0)
+         throw Decoding_Error(name());
+   return (size-position);
+   }
+
+/*
+* Pad with One and Zeros Method
+*/
+void OneAndZeros_Padding::add_padding(secure_vector<byte>& buffer,
+                                      size_t last_byte_pos,
+                                      size_t block_size) const
+   {
+   buffer.push_back(0x80);
+
+   for(size_t i = last_byte_pos + 1; i % block_size; ++i)
+      buffer.push_back(0x00);
+   }
+
+/*
+* Unpad with One and Zeros Method
+*/
+size_t OneAndZeros_Padding::unpad(const byte block[], size_t size) const
+   {
+   while(size)
+      {
+      if(block[size-1] == 0x80)
+         break;
+      if(block[size-1] != 0x00)
+         throw Decoding_Error(name());
+      size--;
+      }
+   if(!size)
+      throw Decoding_Error(name());
+   return (size-1);
+   }
+
+
+}