New encryption API. Piece-wise encryption.

Instead of encrypt(src, dst, key, iv) that encrypts all
data in one go, now we have encrypt_init(key,iv),
encrypt_update(src,dst), and encrypt_finish(dst).

This also causes collateral changes in the internal my_crypt.cc
encryption functions and in the encryption service.

There are wrappers to provide the old all-at-once encryption
functionality. But binlog events are often written piecewise,
they'll need the new api.

1 files changed, 194 insertions, 0 deletions

diff --git a/mysys_ssl/yassl.cc b/mysys_ssl/yassl.cc
new file mode 100644
index 00000000000..9717870fe26
--- /dev/null
+++ b/mysys_ssl/yassl.cc
@@ -0,0 +1,194 @@
+/*
+ Copyright (c) 2015 MariaDB Corporation
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; version 2 of the License.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software
+ Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301  USA */
+
+/*
+  The very minimal subset of OpenSSL's EVP* functions.
+  Just enough for my_crypt.cc to work.
+
+  On the other hand, where it has to implement OpenSSL functionality,
+  it tries to be compatible (e.g. same flags and struct member names).
+*/
+
+#include <openssl/ssl.h>
+#include "aes.hpp"
+
+using yaSSL::yaERR_remove_state;
+
+#define EVP_CIPH_ECB_MODE     0x1
+#define EVP_CIPH_CBC_MODE     0x2
+#define EVP_CIPH_NO_PADDING 0x100
+
+/*
+  note that TaoCrypt::AES object is not explicitly put into EVP_CIPHER_CTX.
+  That's because we need to control when TaoCrypt::AES constructor and
+  destructor are called.
+*/
+typedef struct
+{
+  ulong flags;
+  int encrypt;
+  int key_len;
+  int buf_len;
+  int final_used;
+  uchar tao_buf[sizeof(TaoCrypt::AES)];   // TaoCrypt::AES object
+  uchar oiv[TaoCrypt::AES::BLOCK_SIZE];   // original IV
+  uchar buf[TaoCrypt::AES::BLOCK_SIZE];   // last partial input block
+  uchar final[TaoCrypt::AES::BLOCK_SIZE]; // last decrypted (output) block
+} EVP_CIPHER_CTX;
+
+typedef struct {
+  TaoCrypt::Mode mode;
+  TaoCrypt::word32 key_len;
+} EVP_CIPHER;
+
+#define gen_cipher(mode, MODE, len)                                     \
+  static const EVP_CIPHER *EVP_aes_ ## len ## _ ## mode()               \
+  { static const EVP_CIPHER c={TaoCrypt::MODE, len/8}; return &c; }
+
+gen_cipher(ecb,ECB,128)
+gen_cipher(ecb,ECB,192)
+gen_cipher(ecb,ECB,256)
+gen_cipher(cbc,CBC,128)
+gen_cipher(cbc,CBC,192)
+gen_cipher(cbc,CBC,256)
+
+static inline TaoCrypt::AES *TAO(EVP_CIPHER_CTX *ctx)
+{
+  return (TaoCrypt::AES *)(ctx->tao_buf);
+}
+
+static void EVP_CIPHER_CTX_init(EVP_CIPHER_CTX *ctx)
+{
+  ctx->final_used= ctx->buf_len= ctx->flags= 0;
+}
+
+static int EVP_CIPHER_CTX_cleanup(EVP_CIPHER_CTX *ctx)
+{
+  TAO(ctx)->~AES();
+  return 1;
+}
+
+static int EVP_CIPHER_CTX_set_padding(EVP_CIPHER_CTX *ctx, int pad)
+{
+  if (pad)
+    ctx->flags&= ~EVP_CIPH_NO_PADDING;
+  else
+    ctx->flags|= EVP_CIPH_NO_PADDING;
+  return 1;
+}
+
+static int EVP_CipherInit_ex(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher,
+                             void *, const uchar *key, const uchar *iv, int enc)
+{
+  new (ctx->tao_buf) TaoCrypt::AES(enc ? TaoCrypt::ENCRYPTION
+                                       : TaoCrypt::DECRYPTION, cipher->mode);
+  TAO(ctx)->SetKey(key, cipher->key_len);
+  if (iv)
+  {
+    TAO(ctx)->SetIV(iv);
+    memcpy(ctx->oiv, iv, TaoCrypt::AES::BLOCK_SIZE);
+  }
+  ctx->encrypt= enc;
+  ctx->key_len= cipher->key_len;
+  ctx->flags|= cipher->mode == TaoCrypt::CBC ? EVP_CIPH_CBC_MODE : EVP_CIPH_ECB_MODE;
+  return 1;
+}
+
+static int EVP_CIPHER_CTX_key_length(const EVP_CIPHER_CTX *ctx)
+{
+  return ctx->key_len;
+}
+
+static int EVP_CIPHER_CTX_iv_length(const EVP_CIPHER_CTX *ctx)
+{
+  return ctx->flags & EVP_CIPH_ECB_MODE ? 0 : TaoCrypt::AES::BLOCK_SIZE;
+}
+
+static void do_whole_blocks(EVP_CIPHER_CTX *ctx, uchar *out, int *outl,
+                            const uchar *in, int inl)
+{
+  DBUG_ASSERT(inl);
+  DBUG_ASSERT(inl % TaoCrypt::AES::BLOCK_SIZE == 0);
+  if (ctx->encrypt || (ctx->flags & EVP_CIPH_NO_PADDING))
+  {
+    TAO(ctx)->Process(out, in, inl);
+    *outl+= inl;
+    return;
+  }
+  /* 'final' is only needed when decrypting with padding */
+  if (ctx->final_used)
+  {
+    memcpy(out, ctx->final, TaoCrypt::AES::BLOCK_SIZE);
+    *outl+= TaoCrypt::AES::BLOCK_SIZE;
+    out+= TaoCrypt::AES::BLOCK_SIZE;
+  }
+  inl-= TaoCrypt::AES::BLOCK_SIZE;
+  TAO(ctx)->Process(out, in, inl);
+  *outl+= inl;
+  TAO(ctx)->Process(ctx->final, in + inl, TaoCrypt::AES::BLOCK_SIZE);
+  ctx->final_used= 1;
+}
+
+static int EVP_CipherUpdate(EVP_CIPHER_CTX *ctx, uchar *out, int *outl,
+                            const uchar *in, int inl)
+{
+  *outl= 0;
+  if (ctx->buf_len)
+  {
+    int prefixl= TaoCrypt::AES::BLOCK_SIZE - ctx->buf_len;
+    if (prefixl > inl)
+    {
+      memcpy(ctx->buf + ctx->buf_len, in, inl);
+      ctx->buf_len+= inl;
+      return 1;
+    }
+    memcpy(ctx->buf + ctx->buf_len, in, prefixl);
+    do_whole_blocks(ctx, out, outl, ctx->buf, TaoCrypt::AES::BLOCK_SIZE);
+    in+= prefixl;
+    inl-= prefixl;
+    out+= *outl;
+  }
+  ctx->buf_len= inl % TaoCrypt::AES::BLOCK_SIZE;
+  inl-= ctx->buf_len;
+  memcpy(ctx->buf, in + inl, ctx->buf_len);
+  if (inl)
+    do_whole_blocks(ctx, out, outl, in, inl);
+  return 1;
+}
+
+static int EVP_CipherFinal_ex(EVP_CIPHER_CTX *ctx, uchar *out, int *outl)
+{
+  if (ctx->flags & EVP_CIPH_NO_PADDING)
+    return ctx->buf_len == 0;
+
+  // PKCS#7 padding
+  *outl= 0;
+  if (ctx->encrypt)
+  {
+    int v= TaoCrypt::AES::BLOCK_SIZE - ctx->buf_len;
+    memset(ctx->buf + ctx->buf_len, v, v);
+    do_whole_blocks(ctx, out, outl, ctx->buf, TaoCrypt::AES::BLOCK_SIZE);
+    return 1;
+  }
+  int n= ctx->final[TaoCrypt::AES::BLOCK_SIZE - 1];
+  if (ctx->buf_len || !ctx->final_used ||
+      n < 1 || n > TaoCrypt::AES::BLOCK_SIZE)
+    return 0;
+  *outl= TaoCrypt::AES::BLOCK_SIZE - n;
+  memcpy(out, ctx->final, *outl);
+  return 1;
+}
+