1
2 /*
3 * md2.c : MD2 hash algorithm.
4 *
5 * Part of the Python Cryptography Toolkit
6 *
7 * Originally written by: A.M. Kuchling
8 *
9 * ===================================================================
10 * The contents of this file are dedicated to the public domain. To
11 * the extent that dedication to the public domain is not available,
12 * everyone is granted a worldwide, perpetual, royalty-free,
13 * non-exclusive license to exercise all rights associated with the
14 * contents of this file for any purpose whatsoever.
15 * No rights are reserved.
16 *
17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
18 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
19 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
20 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
21 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
22 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
23 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
24 * SOFTWARE.
25 * ===================================================================
26 *
27 */
28
29
30 #include <string.h>
31 #include "Python.h"
32 #include "pycrypto_compat.h"
33
34 #define MODULE_NAME _MD2
35 #define DIGEST_SIZE 16
36 #define BLOCK_SIZE 64
37
38 /**
39 * id-md2 OBJECT IDENTIFIER ::= {
40 * iso(1) member-body(2) us(840) rsadsi(113549)
41 * digestAlgorithm(2) 2
42 * }
43 */
44 static const char md2_oid[] = { 0x06, 0x08, 0x2a, 0x86, 0x48, 0x86, 0xf7, 0x0d, 0x02, 0x02 };
45
46 #define DER_OID ((void*)&md2_oid)
47 #define DER_OID_SIZE (sizeof md2_oid)
48
49 typedef unsigned char U8;
50 typedef unsigned int U32;
51
52 typedef struct {
53 U8 C[16], X[48];
54 int count;
55 U8 buf[16];
56 } hash_state;
57
hash_init(hash_state * ptr)58 static void hash_init (hash_state *ptr)
59 {
60 memset(ptr->X, 0, 48);
61 memset(ptr->C, 0, 16);
62 ptr->count=0;
63 }
64
65 static U8 S[256] = {
66 41, 46, 67, 201, 162, 216, 124, 1, 61, 54, 84, 161, 236, 240, 6,
67 19, 98, 167, 5, 243, 192, 199, 115, 140, 152, 147, 43, 217, 188,
68 76, 130, 202, 30, 155, 87, 60, 253, 212, 224, 22, 103, 66, 111, 24,
69 138, 23, 229, 18, 190, 78, 196, 214, 218, 158, 222, 73, 160, 251,
70 245, 142, 187, 47, 238, 122, 169, 104, 121, 145, 21, 178, 7, 63,
71 148, 194, 16, 137, 11, 34, 95, 33, 128, 127, 93, 154, 90, 144, 50,
72 39, 53, 62, 204, 231, 191, 247, 151, 3, 255, 25, 48, 179, 72, 165,
73 181, 209, 215, 94, 146, 42, 172, 86, 170, 198, 79, 184, 56, 210,
74 150, 164, 125, 182, 118, 252, 107, 226, 156, 116, 4, 241, 69, 157,
75 112, 89, 100, 113, 135, 32, 134, 91, 207, 101, 230, 45, 168, 2, 27,
76 96, 37, 173, 174, 176, 185, 246, 28, 70, 97, 105, 52, 64, 126, 15,
77 85, 71, 163, 35, 221, 81, 175, 58, 195, 92, 249, 206, 186, 197,
78 234, 38, 44, 83, 13, 110, 133, 40, 132, 9, 211, 223, 205, 244, 65,
79 129, 77, 82, 106, 220, 55, 200, 108, 193, 171, 250, 36, 225, 123,
80 8, 12, 189, 177, 74, 120, 136, 149, 139, 227, 99, 232, 109, 233,
81 203, 213, 254, 59, 0, 29, 57, 242, 239, 183, 14, 102, 88, 208, 228,
82 166, 119, 114, 248, 235, 117, 75, 10, 49, 68, 80, 180, 143, 237,
83 31, 26, 219, 153, 141, 51, 159, 17, 131, 20
84 };
85
86 static void
hash_copy(hash_state * src,hash_state * dest)87 hash_copy(hash_state *src, hash_state *dest)
88 {
89 dest->count=src->count;
90 memcpy(dest->buf, src->buf, dest->count);
91 memcpy(dest->X, src->X, 48);
92 memcpy(dest->C, src->C, 16);
93 }
94
95
hash_update(hash_state * self,const U8 * buf,U32 len)96 static void hash_update (hash_state *self, const U8 *buf, U32 len)
97 {
98 U32 L;
99 while (len)
100 {
101 L=(16-self->count) < len ? (16-self->count) : len;
102 memcpy(self->buf+self->count, buf, L);
103 self->count+=L;
104 buf+=L;
105 len-=L;
106 if (self->count==16)
107 {
108 U8 t;
109 int i,j;
110
111 self->count=0;
112 memcpy(self->X+16, self->buf, 16);
113 t=self->C[15];
114 for(i=0; i<16; i++)
115 {
116 self->X[32+i]=self->X[16+i]^self->X[i];
117 t=self->C[i]^=S[self->buf[i]^t];
118 }
119
120 t=0;
121 for(i=0; i<18; i++)
122 {
123 for(j=0; j<48; j++)
124 t=self->X[j]^=S[t];
125 t=(t+i) & 0xFF;
126 }
127 }
128 }
129 }
130
131 static PyObject *
hash_digest(const hash_state * self)132 hash_digest (const hash_state *self)
133 {
134 U8 padding[16];
135 U32 padlen;
136 hash_state temp;
137 int i;
138
139 memcpy(&temp, self, sizeof(hash_state));
140 padlen= 16-self->count;
141 for(i=0; i<padlen; i++) padding[i]=padlen;
142 hash_update(&temp, padding, padlen);
143 hash_update(&temp, temp.C, 16);
144 return PyBytes_FromStringAndSize((char *) temp.X, 16);
145 }
146
147 #include "hash_template.c"
148