1 files changed, 240 insertions, 0 deletions
diff --git a/src/lib/prov/commoncrypto/commoncrypto_mode.cpp b/src/lib/prov/commoncrypto/commoncrypto_mode.cpp
new file mode 100644
index 000000000..baae11679
--- /dev/null
+++ b/src/lib/prov/commoncrypto/commoncrypto_mode.cpp
@@ -0,0 +1,240 @@
+/*
+* Cipher Modes via CommonCrypto
+* (C) 2018 Jose Pereira
+*
+* Botan is released under the Simplified BSD License (see license.txt)
+*/
+
+#include <botan/cipher_mode.h>
+#include <botan/internal/rounding.h>
+#include <botan/internal/commoncrypto.h>
+
+#include "commoncrypto_utils.h"
+
+#include <limits.h>
+
+namespace Botan {
+
+namespace {
+
+class CommonCrypto_Cipher_Mode final : public Cipher_Mode
+   {
+   public:
+      CommonCrypto_Cipher_Mode(const std::string& name,
+                               Cipher_Dir direction,
+                               const CommonCryptor_Opts& opts);
+
+      ~CommonCrypto_Cipher_Mode();
+
+      std::string provider() const override { return "commoncrypto"; }
+      std::string name() const override { return m_mode_name; }
+
+      void start_msg(const uint8_t nonce[], size_t nonce_len) override;
+      size_t process(uint8_t msg[], size_t msg_len) override;
+      void finish(secure_vector<uint8_t>& final_block, size_t offset0) override;
+      size_t output_length(size_t input_length) const override;
+      size_t update_granularity() const override;
+      size_t minimum_final_size() const override;
+      size_t default_nonce_length() const override;
+      bool valid_nonce_length(size_t nonce_len) const override;
+      void clear() override;
+      void reset() override;
+      Key_Length_Specification key_spec() const override;
+
+   private:
+      void key_schedule(const uint8_t key[], size_t length) override;
+
+      const std::string m_mode_name;
+      Cipher_Dir m_direction;
+      CommonCryptor_Opts m_opts;
+      CCCryptorRef m_cipher = nullptr;
+      bool m_key_set;
+      bool m_nonce_set;
+   };
+
+CommonCrypto_Cipher_Mode::CommonCrypto_Cipher_Mode(const std::string& name,
+      Cipher_Dir direction, const CommonCryptor_Opts& opts) :
+   m_mode_name(name),
+   m_direction(direction),
+   m_opts(opts),
+   m_key_set(false),
+   m_nonce_set(false)
+   {
+   }
+
+CommonCrypto_Cipher_Mode::~CommonCrypto_Cipher_Mode()
+   {
+   if(m_cipher)
+      {
+      CCCryptorRelease(m_cipher);
+      }
+   }
+
+void CommonCrypto_Cipher_Mode::start_msg(const uint8_t nonce[], size_t nonce_len)
+   {
+   verify_key_set(m_key_set);
+
+   if(!valid_nonce_length(nonce_len))
+      { throw Invalid_IV_Length(name(), nonce_len); }
+   if(nonce_len)
+      {
+      CCCryptorStatus status = CCCryptorReset(m_cipher, nonce);
+      if(status != kCCSuccess)
+         {
+         throw CommonCrypto_Error("CCCryptorReset on start_msg", status);
+         }
+      }
+   m_nonce_set = true;
+   }
+
+size_t CommonCrypto_Cipher_Mode::process(uint8_t msg[], size_t msg_len)
+   {
+   verify_key_set(m_key_set);
+   BOTAN_STATE_CHECK(m_nonce_set);
+
+   if(msg_len == 0)
+      { return 0; }
+   if(msg_len > INT_MAX)
+      { throw Internal_Error("msg_len overflow"); }
+   size_t outl = CCCryptorGetOutputLength(m_cipher, msg_len, false);
+
+   secure_vector<uint8_t> out(outl);
+
+   if(m_opts.padding == ccNoPadding && msg_len % m_opts.block_size)
+      {
+      msg_len = outl;
+      }
+
+   CCCryptorStatus status = CCCryptorUpdate(m_cipher, msg, msg_len,
+                            out.data(), outl, &outl);
+   if(status != kCCSuccess)
+      {
+      throw CommonCrypto_Error("CCCryptorUpdate", status);
+      }
+   memcpy(msg, out.data(), outl);
+
+   return outl;
+   }
+
+void CommonCrypto_Cipher_Mode::finish(secure_vector<uint8_t>& buffer,
+                                      size_t offset)
+   {
+   verify_key_set(m_key_set);
+
+   BOTAN_ASSERT(buffer.size() >= offset, "Offset ok");
+   uint8_t* buf = buffer.data() + offset;
+   const size_t buf_size = buffer.size() - offset;
+
+   size_t written = process(buf, buf_size);
+
+   size_t outl = CCCryptorGetOutputLength(m_cipher, buf_size - written, true);
+   secure_vector<uint8_t> out(outl);
+
+   CCCryptorStatus status = CCCryptorFinal(
+                               m_cipher, out.data(), outl, &outl);
+   if(status != kCCSuccess)
+      {
+      throw CommonCrypto_Error("CCCryptorFinal", status);
+      }
+
+   size_t new_len = offset + written + outl;
+   if(m_opts.padding != ccNoPadding || buffer.size() < new_len)
+      {
+      buffer.resize(new_len);
+      }
+   memcpy(buffer.data() - offset + written, out.data(), outl);
+   written += outl;
+   }
+
+size_t CommonCrypto_Cipher_Mode::update_granularity() const
+   {
+   return m_opts.block_size * BOTAN_BLOCK_CIPHER_PAR_MULT;
+   }
+
+size_t CommonCrypto_Cipher_Mode::minimum_final_size() const
+   {
+   return 0;
+   }
+
+size_t CommonCrypto_Cipher_Mode::default_nonce_length() const
+   {
+   return m_opts.block_size;
+   }
+
+bool CommonCrypto_Cipher_Mode::valid_nonce_length(size_t nonce_len) const
+   {
+   return (nonce_len == 0 || nonce_len == m_opts.block_size);
+   }
+
+size_t CommonCrypto_Cipher_Mode::output_length(size_t input_length) const
+   {
+   if(input_length == 0)
+      { return m_opts.block_size; }
+   else
+      { return round_up(input_length, m_opts.block_size); }
+   }
+
+void CommonCrypto_Cipher_Mode::clear()
+   {
+   m_key_set = false;
+
+   if(m_cipher == nullptr)
+      {
+      return;
+      }
+
+   if(m_cipher)
+      {
+      CCCryptorRelease(m_cipher);
+      m_cipher = nullptr;
+      }
+   }
+
+void CommonCrypto_Cipher_Mode::reset()
+   {
+   if(m_cipher == nullptr)
+      {
+      return;
+      }
+   CCCryptorStatus status = CCCryptorReset(m_cipher, nullptr);
+   if(status != kCCSuccess)
+      {
+      throw CommonCrypto_Error("CCCryptorReset", status);
+      }
+   }
+
+Key_Length_Specification CommonCrypto_Cipher_Mode::key_spec() const
+   {
+   return m_opts.key_spec;
+   }
+
+void CommonCrypto_Cipher_Mode::key_schedule(const uint8_t key[], size_t length)
+   {
+   CCCryptorStatus status;
+   CCOperation op = m_direction == ENCRYPTION ? kCCEncrypt : kCCDecrypt;
+   status = CCCryptorCreateWithMode(op, m_opts.mode, m_opts.algo, m_opts.padding,
+                                    nullptr, key, length, nullptr, 0, 0, 0, &m_cipher);
+   if(status != kCCSuccess)
+      {
+      throw CommonCrypto_Error("CCCryptorCreate", status);
+      }
+
+   m_key_set = true;
+   }
+}
+
+Cipher_Mode*
+make_commoncrypto_cipher_mode(const std::string& name, Cipher_Dir direction)
+   {
+
+   try
+      {
+      CommonCryptor_Opts opts = commoncrypto_opts_from_algo(name);
+      return new CommonCrypto_Cipher_Mode(name, direction, opts);
+      }
+   catch(CommonCrypto_Error e)
+      {
+      return nullptr;
+      }
+   }
+}