Dash Core Source Documentation (0.16.0.1)

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aes.cpp
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1 // Copyright (c) 2016 The Bitcoin Core developers
2 // Distributed under the MIT software license, see the accompanying
3 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
4 
5 #include <crypto/aes.h>
6 #include <crypto/common.h>
7 
8 #include <assert.h>
9 #include <string.h>
10 
11 extern "C" {
12 #include <crypto/ctaes/ctaes.c>
13 }
14 
15 AES128Encrypt::AES128Encrypt(const unsigned char key[16])
16 {
17  AES128_init(&ctx, key);
18 }
19 
21 {
22  memset(&ctx, 0, sizeof(ctx));
23 }
24 
25 void AES128Encrypt::Encrypt(unsigned char ciphertext[16], const unsigned char plaintext[16]) const
26 {
27  AES128_encrypt(&ctx, 1, ciphertext, plaintext);
28 }
29 
30 AES128Decrypt::AES128Decrypt(const unsigned char key[16])
31 {
32  AES128_init(&ctx, key);
33 }
34 
36 {
37  memset(&ctx, 0, sizeof(ctx));
38 }
39 
40 void AES128Decrypt::Decrypt(unsigned char plaintext[16], const unsigned char ciphertext[16]) const
41 {
42  AES128_decrypt(&ctx, 1, plaintext, ciphertext);
43 }
44 
45 AES256Encrypt::AES256Encrypt(const unsigned char key[32])
46 {
47  AES256_init(&ctx, key);
48 }
49 
51 {
52  memset(&ctx, 0, sizeof(ctx));
53 }
54 
55 void AES256Encrypt::Encrypt(unsigned char ciphertext[16], const unsigned char plaintext[16]) const
56 {
57  AES256_encrypt(&ctx, 1, ciphertext, plaintext);
58 }
59 
60 AES256Decrypt::AES256Decrypt(const unsigned char key[32])
61 {
62  AES256_init(&ctx, key);
63 }
64 
66 {
67  memset(&ctx, 0, sizeof(ctx));
68 }
69 
70 void AES256Decrypt::Decrypt(unsigned char plaintext[16], const unsigned char ciphertext[16]) const
71 {
72  AES256_decrypt(&ctx, 1, plaintext, ciphertext);
73 }
74 
75 
76 template <typename T>
77 static int CBCEncrypt(const T& enc, const unsigned char iv[AES_BLOCKSIZE], const unsigned char* data, int size, bool pad, unsigned char* out)
78 {
79  int written = 0;
80  int padsize = size % AES_BLOCKSIZE;
81  unsigned char mixed[AES_BLOCKSIZE];
82 
83  if (!data || !size || !out)
84  return 0;
85 
86  if (!pad && padsize != 0)
87  return 0;
88 
89  memcpy(mixed, iv, AES_BLOCKSIZE);
90 
91  // Write all but the last block
92  while (written + AES_BLOCKSIZE <= size) {
93  for (int i = 0; i != AES_BLOCKSIZE; i++)
94  mixed[i] ^= *data++;
95  enc.Encrypt(out + written, mixed);
96  memcpy(mixed, out + written, AES_BLOCKSIZE);
97  written += AES_BLOCKSIZE;
98  }
99  if (pad) {
100  // For all that remains, pad each byte with the value of the remaining
101  // space. If there is none, pad by a full block.
102  for (int i = 0; i != padsize; i++)
103  mixed[i] ^= *data++;
104  for (int i = padsize; i != AES_BLOCKSIZE; i++)
105  mixed[i] ^= AES_BLOCKSIZE - padsize;
106  enc.Encrypt(out + written, mixed);
107  written += AES_BLOCKSIZE;
108  }
109  return written;
110 }
111 
112 template <typename T>
113 static int CBCDecrypt(const T& dec, const unsigned char iv[AES_BLOCKSIZE], const unsigned char* data, int size, bool pad, unsigned char* out)
114 {
115  int written = 0;
116  bool fail = false;
117  const unsigned char* prev = iv;
118 
119  if (!data || !size || !out)
120  return 0;
121 
122  if (size % AES_BLOCKSIZE != 0)
123  return 0;
124 
125  // Decrypt all data. Padding will be checked in the output.
126  while (written != size) {
127  dec.Decrypt(out, data + written);
128  for (int i = 0; i != AES_BLOCKSIZE; i++)
129  *out++ ^= prev[i];
130  prev = data + written;
131  written += AES_BLOCKSIZE;
132  }
133 
134  // When decrypting padding, attempt to run in constant-time
135  if (pad) {
136  // If used, padding size is the value of the last decrypted byte. For
137  // it to be valid, It must be between 1 and AES_BLOCKSIZE.
138  unsigned char padsize = *--out;
139  fail = !padsize | (padsize > AES_BLOCKSIZE);
140 
141  // If not well-formed, treat it as though there's no padding.
142  padsize *= !fail;
143 
144  // All padding must equal the last byte otherwise it's not well-formed
145  for (int i = AES_BLOCKSIZE; i != 0; i--)
146  fail |= ((i > AES_BLOCKSIZE - padsize) & (*out-- != padsize));
147 
148  written -= padsize;
149  }
150  return written * !fail;
151 }
152 
153 AES256CBCEncrypt::AES256CBCEncrypt(const unsigned char key[AES256_KEYSIZE], const unsigned char ivIn[AES_BLOCKSIZE], bool padIn)
154  : enc(key), pad(padIn)
155 {
156  memcpy(iv, ivIn, AES_BLOCKSIZE);
157 }
158 
159 int AES256CBCEncrypt::Encrypt(const unsigned char* data, int size, unsigned char* out) const
160 {
161  return CBCEncrypt(enc, iv, data, size, pad, out);
162 }
163 
165 {
166  memset(iv, 0, sizeof(iv));
167 }
168 
169 AES256CBCDecrypt::AES256CBCDecrypt(const unsigned char key[AES256_KEYSIZE], const unsigned char ivIn[AES_BLOCKSIZE], bool padIn)
170  : dec(key), pad(padIn)
171 {
172  memcpy(iv, ivIn, AES_BLOCKSIZE);
173 }
174 
175 
176 int AES256CBCDecrypt::Decrypt(const unsigned char* data, int size, unsigned char* out) const
177 {
178  return CBCDecrypt(dec, iv, data, size, pad, out);
179 }
180 
182 {
183  memset(iv, 0, sizeof(iv));
184 }
185 
186 AES128CBCEncrypt::AES128CBCEncrypt(const unsigned char key[AES128_KEYSIZE], const unsigned char ivIn[AES_BLOCKSIZE], bool padIn)
187  : enc(key), pad(padIn)
188 {
189  memcpy(iv, ivIn, AES_BLOCKSIZE);
190 }
191 
193 {
194  memset(iv, 0, AES_BLOCKSIZE);
195 }
196 
197 int AES128CBCEncrypt::Encrypt(const unsigned char* data, int size, unsigned char* out) const
198 {
199  return CBCEncrypt(enc, iv, data, size, pad, out);
200 }
201 
202 AES128CBCDecrypt::AES128CBCDecrypt(const unsigned char key[AES128_KEYSIZE], const unsigned char ivIn[AES_BLOCKSIZE], bool padIn)
203  : dec(key), pad(padIn)
204 {
205  memcpy(iv, ivIn, AES_BLOCKSIZE);
206 }
207 
209 {
210  memset(iv, 0, AES_BLOCKSIZE);
211 }
212 
213 int AES128CBCDecrypt::Decrypt(const unsigned char* data, int size, unsigned char* out) const
214 {
215  return CBCDecrypt(dec, iv, data, size, pad, out);
216 }
void AES256_init(AES256_ctx *ctx, const unsigned char *key32)
Definition: ctaes.c:538
AES256_ctx ctx
Definition: aes.h:58
AES256Encrypt(const unsigned char key[32])
Definition: aes.cpp:45
static const int AES256_KEYSIZE
Definition: aes.h:16
int Decrypt(const unsigned char *data, int size, unsigned char *out) const
Definition: aes.cpp:213
static int CBCEncrypt(const T &enc, const unsigned char iv[AES_BLOCKSIZE], const unsigned char *data, int size, bool pad, unsigned char *out)
Definition: aes.cpp:77
void AES128_encrypt(const AES128_ctx *ctx, size_t blocks, unsigned char *cipher16, const unsigned char *plain16)
Definition: ctaes.c:501
AES128Encrypt(const unsigned char key[16])
Definition: aes.cpp:15
void Encrypt(unsigned char ciphertext[16], const unsigned char plaintext[16]) const
Definition: aes.cpp:55
const AES256Decrypt dec
Definition: aes.h:87
AES128CBCEncrypt(const unsigned char key[AES128_KEYSIZE], const unsigned char ivIn[AES_BLOCKSIZE], bool padIn)
Definition: aes.cpp:186
void AES256_encrypt(const AES256_ctx *ctx, size_t blocks, unsigned char *cipher16, const unsigned char *plain16)
Definition: ctaes.c:542
~AES256Encrypt()
Definition: aes.cpp:50
const AES128Encrypt enc
Definition: aes.h:100
unsigned char iv[AES_BLOCKSIZE]
Definition: aes.h:89
void AES128_decrypt(const AES128_ctx *ctx, size_t blocks, unsigned char *plain16, const unsigned char *cipher16)
Definition: ctaes.c:509
int Decrypt(const unsigned char *data, int size, unsigned char *out) const
Definition: aes.cpp:176
void Decrypt(unsigned char plaintext[16], const unsigned char ciphertext[16]) const
Definition: aes.cpp:70
~AES128Encrypt()
Definition: aes.cpp:20
void Decrypt(unsigned char plaintext[16], const unsigned char ciphertext[16]) const
Definition: aes.cpp:40
static int CBCDecrypt(const T &dec, const unsigned char iv[AES_BLOCKSIZE], const unsigned char *data, int size, bool pad, unsigned char *out)
Definition: aes.cpp:113
~AES128CBCDecrypt()
Definition: aes.cpp:208
void AES256_decrypt(const AES256_ctx *ctx, size_t blocks, unsigned char *plain16, const unsigned char *cipher16)
Definition: ctaes.c:550
const bool pad
Definition: aes.h:101
const AES128Decrypt dec
Definition: aes.h:113
const bool pad
Definition: aes.h:88
~AES256CBCDecrypt()
Definition: aes.cpp:181
unsigned char iv[AES_BLOCKSIZE]
Definition: aes.h:115
int Encrypt(const unsigned char *data, int size, unsigned char *out) const
Definition: aes.cpp:197
AES256CBCDecrypt(const unsigned char key[AES256_KEYSIZE], const unsigned char ivIn[AES_BLOCKSIZE], bool padIn)
Definition: aes.cpp:169
void AES128_init(AES128_ctx *ctx, const unsigned char *key16)
Definition: ctaes.c:497
AES256CBCEncrypt(const unsigned char key[AES256_KEYSIZE], const unsigned char ivIn[AES_BLOCKSIZE], bool padIn)
Definition: aes.cpp:153
~AES128Decrypt()
Definition: aes.cpp:35
int Encrypt(const unsigned char *data, int size, unsigned char *out) const
Definition: aes.cpp:159
void Encrypt(unsigned char ciphertext[16], const unsigned char plaintext[16]) const
Definition: aes.cpp:25
const AES256Encrypt enc
Definition: aes.h:74
~AES256Decrypt()
Definition: aes.cpp:65
void * memcpy(void *a, const void *b, size_t c)
AES256_ctx ctx
Definition: aes.h:46
static const int AES128_KEYSIZE
Definition: aes.h:15
AES128Decrypt(const unsigned char key[16])
Definition: aes.cpp:30
~AES256CBCEncrypt()
Definition: aes.cpp:164
~AES128CBCEncrypt()
Definition: aes.cpp:192
unsigned char iv[AES_BLOCKSIZE]
Definition: aes.h:102
AES128_ctx ctx
Definition: aes.h:22
const bool pad
Definition: aes.h:75
unsigned char iv[AES_BLOCKSIZE]
Definition: aes.h:76
AES128CBCDecrypt(const unsigned char key[AES128_KEYSIZE], const unsigned char ivIn[AES_BLOCKSIZE], bool padIn)
Definition: aes.cpp:202
AES256Decrypt(const unsigned char key[32])
Definition: aes.cpp:60
static const int AES_BLOCKSIZE
Definition: aes.h:14
const bool pad
Definition: aes.h:114
AES128_ctx ctx
Definition: aes.h:34
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