Modularize PBEs (password-based encryption schemes)

2 files changed, 211 insertions, 0 deletions

diff --git a/src/pbe/pbes1/pbes1.cpp b/src/pbe/pbes1/pbes1.cpp
new file mode 100644
index 000000000..84b34eed6
--- /dev/null
+++ b/src/pbe/pbes1/pbes1.cpp
@@ -0,0 +1,169 @@
+/*************************************************
+* PKCS #5 PBES1 Source File                      *
+* (C) 1999-2007 Jack Lloyd                       *
+*************************************************/
+
+#include <botan/pbe_pkcs.h>
+#include <botan/der_enc.h>
+#include <botan/ber_dec.h>
+#include <botan/parsing.h>
+#include <botan/lookup.h>
+#include <botan/libstate.h>
+#include <algorithm>
+#include <memory>
+
+namespace Botan {
+
+/*************************************************
+* Encrypt some bytes using PBES1                 *
+*************************************************/
+void PBE_PKCS5v15::write(const byte input[], u32bit length)
+   {
+   while(length)
+      {
+      u32bit put = std::min(DEFAULT_BUFFERSIZE, length);
+      pipe.write(input, length);
+      flush_pipe(true);
+      length -= put;
+      }
+   }
+
+/*************************************************
+* Start encrypting with PBES1                    *
+*************************************************/
+void PBE_PKCS5v15::start_msg()
+   {
+   pipe.append(get_cipher(cipher, key, iv, direction));
+   pipe.start_msg();
+   if(pipe.message_count() > 1)
+      pipe.set_default_msg(pipe.default_msg() + 1);
+   }
+
+/*************************************************
+* Finish encrypting with PBES1                   *
+*************************************************/
+void PBE_PKCS5v15::end_msg()
+   {
+   pipe.end_msg();
+   flush_pipe(false);
+   pipe.reset();
+   }
+
+/*************************************************
+* Flush the pipe                                 *
+*************************************************/
+void PBE_PKCS5v15::flush_pipe(bool safe_to_skip)
+   {
+   if(safe_to_skip && pipe.remaining() < 64)
+      return;
+
+   SecureVector<byte> buffer(DEFAULT_BUFFERSIZE);
+   while(pipe.remaining())
+      {
+      u32bit got = pipe.read(buffer, buffer.size());
+      send(buffer, got);
+      }
+   }
+
+/*************************************************
+* Set the passphrase to use                      *
+*************************************************/
+void PBE_PKCS5v15::set_key(const std::string& passphrase)
+   {
+   std::auto_ptr<S2K> pbkdf(get_s2k("PBKDF1(" + digest + ")"));
+   pbkdf->set_iterations(iterations);
+   pbkdf->change_salt(salt, salt.size());
+   SymmetricKey key_and_iv = pbkdf->derive_key(16, passphrase);
+
+   key.set(key_and_iv.begin(), 8);
+   iv.set(key_and_iv.begin() + 8, 8);
+   }
+
+/*************************************************
+* Create a new set of PBES1 parameters           *
+*************************************************/
+void PBE_PKCS5v15::new_params(RandomNumberGenerator& rng)
+   {
+   iterations = 2048;
+   salt.create(8);
+   rng.randomize(salt, salt.size());
+   }
+
+/*************************************************
+* Encode PKCS#5 PBES1 parameters                 *
+*************************************************/
+MemoryVector<byte> PBE_PKCS5v15::encode_params() const
+   {
+   return DER_Encoder()
+      .start_cons(SEQUENCE)
+         .encode(salt, OCTET_STRING)
+         .encode(iterations)
+      .end_cons()
+   .get_contents();
+   }
+
+/*************************************************
+* Decode PKCS#5 PBES1 parameters                 *
+*************************************************/
+void PBE_PKCS5v15::decode_params(DataSource& source)
+   {
+   BER_Decoder(source)
+      .start_cons(SEQUENCE)
+         .decode(salt, OCTET_STRING)
+         .decode(iterations)
+         .verify_end()
+      .end_cons();
+
+   if(salt.size() != 8)
+      throw Decoding_Error("PBES1: Encoded salt is not 8 octets");
+   }
+
+/*************************************************
+* Return an OID for this PBES1 type              *
+*************************************************/
+OID PBE_PKCS5v15::get_oid() const
+   {
+   const OID base_pbes1_oid("1.2.840.113549.1.5");
+   if(cipher == "DES/CBC" && digest == "MD2")
+      return (base_pbes1_oid + 1);
+   else if(cipher == "DES/CBC" && digest == "MD5")
+      return (base_pbes1_oid + 3);
+   else if(cipher == "DES/CBC" && digest == "SHA-160")
+      return (base_pbes1_oid + 10);
+   else if(cipher == "RC2/CBC" && digest == "MD2")
+      return (base_pbes1_oid + 4);
+   else if(cipher == "RC2/CBC" && digest == "MD5")
+      return (base_pbes1_oid + 6);
+   else if(cipher == "RC2/CBC" && digest == "SHA-160")
+      return (base_pbes1_oid + 11);
+   else
+      throw Internal_Error("PBE-PKCS5 v1.5: get_oid() has run out of options");
+   }
+
+/*************************************************
+* PKCS#5 v1.5 PBE Constructor                    *
+*************************************************/
+PBE_PKCS5v15::PBE_PKCS5v15(const std::string& d_algo,
+                           const std::string& c_algo, Cipher_Dir dir) :
+   direction(dir),
+   digest(global_state().deref_alias(d_algo)),
+   cipher(c_algo)
+   {
+   std::vector<std::string> cipher_spec = split_on(c_algo, '/');
+   if(cipher_spec.size() != 2)
+      throw Invalid_Argument("PBE-PKCS5 v1.5: Invalid cipher spec " + c_algo);
+   const std::string cipher_algo = global_state().deref_alias(cipher_spec[0]);
+   const std::string cipher_mode = cipher_spec[1];
+
+   if(!have_block_cipher(cipher_algo))
+      throw Algorithm_Not_Found(cipher_algo);
+   if(!have_hash(digest))
+      throw Algorithm_Not_Found(digest);
+
+   if((cipher_algo != "DES" && cipher_algo != "RC2") || (cipher_mode != "CBC"))
+      throw Invalid_Argument("PBE-PKCS5 v1.5: Invalid cipher " + cipher);
+   if(digest != "MD2" && digest != "MD5" && digest != "SHA-160")
+      throw Invalid_Argument("PBE-PKCS5 v1.5: Invalid digest " + digest);
+   }
+
+}
diff --git a/src/pbe/pbes1/pbes1.h b/src/pbe/pbes1/pbes1.h
new file mode 100644
index 000000000..89d611b4e
--- /dev/null
+++ b/src/pbe/pbes1/pbes1.h
@@ -0,0 +1,42 @@
+/*************************************************
+* PKCS #5 v1.5 PBE Header File                   *
+* (C) 1999-2007 Jack Lloyd                       *
+*************************************************/
+
+#ifndef BOTAN_PBE_PKCS_V15_H__
+#define BOTAN_PBE_PKCS_V15_H__
+
+#include <botan/pbe.h>
+#include <botan/pipe.h>
+#include <botan/enums.h>
+
+namespace Botan {
+
+/*************************************************
+* PKCS#5 v1.5 PBE                                *
+*************************************************/
+class BOTAN_DLL PBE_PKCS5v15 : public PBE
+   {
+   public:
+      void write(const byte[], u32bit);
+      void start_msg();
+      void end_msg();
+      PBE_PKCS5v15(const std::string&, const std::string&, Cipher_Dir);
+   private:
+      void set_key(const std::string&);
+      void new_params(RandomNumberGenerator& rng);
+      MemoryVector<byte> encode_params() const;
+      void decode_params(DataSource&);
+      OID get_oid() const;
+
+      void flush_pipe(bool);
+      const Cipher_Dir direction;
+      const std::string digest, cipher;
+      SecureVector<byte> salt, key, iv;
+      u32bit iterations;
+      Pipe pipe;
+   };
+
+}
+
+#endif