summaryrefslogtreecommitdiff
path: root/mysys_ssl/yassl.cc
blob: 96b6f6867fe1f5f5a98d2c5fc80126d027521b59 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
/*
 Copyright (c) 2015, 2017, 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 02110-1335  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;
using yaSSL::yaRAND_bytes;

#define EVP_CIPH_ECB_MODE     0x1U
#define EVP_CIPH_CBC_MODE     0x2U
#define EVP_CIPH_NO_PADDING 0x100U

/*
  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 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);
  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;
}