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
192
193
194
195
196
197
198
199
200
201
202
203
204
205
|
/*
* Cipher Modes via OpenSSL
* (C) 1999-2010,2015 Jack Lloyd
* (C) 2017 Alexander Bluhm (genua GmbH)
*
* Botan is released under the Simplified BSD License (see license.txt)
*/
#include <botan/cipher_mode.h>
#include <botan/internal/rounding.h>
#include <botan/internal/openssl.h>
#include <openssl/evp.h>
#include <limits.h>
namespace Botan {
namespace {
class OpenSSL_Cipher_Mode final : public Cipher_Mode
{
public:
OpenSSL_Cipher_Mode(const std::string& name,
const EVP_CIPHER* cipher,
Cipher_Dir direction);
~OpenSSL_Cipher_Mode();
std::string provider() const override { return "openssl"; }
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;
const Cipher_Dir m_direction;
size_t m_block_size;
EVP_CIPHER_CTX* m_cipher;
};
OpenSSL_Cipher_Mode::OpenSSL_Cipher_Mode(const std::string& name,
const EVP_CIPHER* algo,
Cipher_Dir direction) :
m_mode_name(name),
m_direction(direction)
{
m_block_size = EVP_CIPHER_block_size(algo);
if(EVP_CIPHER_mode(algo) != EVP_CIPH_CBC_MODE)
throw Invalid_Argument("OpenSSL_BlockCipher: Non-CBC EVP was passed in");
m_cipher = EVP_CIPHER_CTX_new();
if (m_cipher == nullptr)
throw OpenSSL_Error("Can't allocate new context");
EVP_CIPHER_CTX_init(m_cipher);
if(!EVP_CipherInit_ex(m_cipher, algo, nullptr, nullptr, nullptr,
m_direction == ENCRYPTION ? 1 : 0))
throw OpenSSL_Error("EVP_CipherInit_ex");
if(!EVP_CIPHER_CTX_set_padding(m_cipher, 0))
throw OpenSSL_Error("EVP_CIPHER_CTX_set_padding");
}
OpenSSL_Cipher_Mode::~OpenSSL_Cipher_Mode()
{
EVP_CIPHER_CTX_free(m_cipher);
}
void OpenSSL_Cipher_Mode::start_msg(const uint8_t nonce[], size_t nonce_len)
{
if(!valid_nonce_length(nonce_len))
throw Invalid_IV_Length(name(), nonce_len);
if(nonce_len)
{
if(!EVP_CipherInit_ex(m_cipher, nullptr, nullptr, nullptr, nonce, -1))
throw OpenSSL_Error("EVP_CipherInit_ex nonce");
}
}
size_t OpenSSL_Cipher_Mode::process(uint8_t msg[], size_t msg_len)
{
if(msg_len == 0)
return 0;
if(msg_len > INT_MAX)
throw Internal_Error("msg_len overflow");
int outl = msg_len;
secure_vector<uint8_t> out(outl);
if(!EVP_CipherUpdate(m_cipher, out.data(), &outl, msg, msg_len))
throw OpenSSL_Error("EVP_CipherUpdate");
memcpy(msg, out.data(), outl);
return outl;
}
void OpenSSL_Cipher_Mode::finish(secure_vector<uint8_t>& buffer,
size_t offset)
{
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);
int outl = buf_size - written;
secure_vector<uint8_t> out(outl);
if(!EVP_CipherFinal_ex(m_cipher, out.data(), &outl))
throw OpenSSL_Error("EVP_CipherFinal_ex");
memcpy(buf + written, out.data(), outl);
written += outl;
buffer.resize(offset + written);
}
size_t OpenSSL_Cipher_Mode::update_granularity() const
{
return m_block_size * BOTAN_BLOCK_CIPHER_PAR_MULT;
}
size_t OpenSSL_Cipher_Mode::minimum_final_size() const
{
return 0; // no padding
}
size_t OpenSSL_Cipher_Mode::default_nonce_length() const
{
return m_block_size;
}
bool OpenSSL_Cipher_Mode::valid_nonce_length(size_t nonce_len) const
{
return (nonce_len == 0 || nonce_len == m_block_size);
}
size_t OpenSSL_Cipher_Mode::output_length(size_t input_length) const
{
if(input_length == 0)
return m_block_size;
else
return round_up(input_length, m_block_size);
}
void OpenSSL_Cipher_Mode::clear()
{
const EVP_CIPHER* algo = EVP_CIPHER_CTX_cipher(m_cipher);
if(!EVP_CIPHER_CTX_cleanup(m_cipher))
throw OpenSSL_Error("EVP_CIPHER_CTX_cleanup");
EVP_CIPHER_CTX_init(m_cipher);
if(!EVP_CipherInit_ex(m_cipher, algo, nullptr, nullptr, nullptr,
m_direction == ENCRYPTION ? 1 : 0))
throw OpenSSL_Error("EVP_CipherInit_ex clear");
if(!EVP_CIPHER_CTX_set_padding(m_cipher, 0))
throw OpenSSL_Error("EVP_CIPHER_CTX_set_padding clear");
}
void OpenSSL_Cipher_Mode::reset()
{
if(!EVP_CipherInit_ex(m_cipher, nullptr, nullptr, nullptr, nullptr, -1))
throw OpenSSL_Error("EVP_CipherInit_ex clear");
}
Key_Length_Specification OpenSSL_Cipher_Mode::key_spec() const
{
return Key_Length_Specification(EVP_CIPHER_CTX_key_length(m_cipher));
}
void OpenSSL_Cipher_Mode::key_schedule(const uint8_t key[], size_t length)
{
if(!EVP_CIPHER_CTX_set_key_length(m_cipher, length))
throw OpenSSL_Error("EVP_CIPHER_CTX_set_key_length");
if(!EVP_CipherInit_ex(m_cipher, nullptr, nullptr, key, nullptr, -1))
throw OpenSSL_Error("EVP_CipherInit_ex key");
}
}
Cipher_Mode*
make_openssl_cipher_mode(const std::string& name, Cipher_Dir direction)
{
#define MAKE_OPENSSL_MODE(evp_fn) \
new OpenSSL_Cipher_Mode(name, (evp_fn)(), direction)
#if defined(BOTAN_HAS_AES) && defined(BOTAN_HAS_MODE_CBC) && !defined(OPENSSL_NO_AES)
if(name == "AES-128/CBC/NoPadding")
return MAKE_OPENSSL_MODE(EVP_aes_128_cbc);
if(name == "AES-192/CBC/NoPadding")
return MAKE_OPENSSL_MODE(EVP_aes_192_cbc);
if(name == "AES-256/CBC/NoPadding")
return MAKE_OPENSSL_MODE(EVP_aes_256_cbc);
#endif
#undef MAKE_OPENSSL_MODE
return nullptr;
}
}
|
