xref: /openssl/crypto/idea/i_cbc.c (revision 33388b44)
1 /*
2  * Copyright 1995-2020 The OpenSSL Project Authors. All Rights Reserved.
3  *
4  * Licensed under the Apache License 2.0 (the "License").  You may not use
5  * this file except in compliance with the License.  You can obtain a copy
6  * in the file LICENSE in the source distribution or at
7  * https://www.openssl.org/source/license.html
8  */
9 
10 /*
11  * IDEA low level APIs are deprecated for public use, but still ok for internal
12  * use where we're using them to implement the higher level EVP interface, as is
13  * the case here.
14  */
15 #include "internal/deprecated.h"
16 
17 #include <openssl/idea.h>
18 #include "idea_local.h"
19 
IDEA_cbc_encrypt(const unsigned char * in,unsigned char * out,long length,IDEA_KEY_SCHEDULE * ks,unsigned char * iv,int encrypt)20 void IDEA_cbc_encrypt(const unsigned char *in, unsigned char *out,
21                       long length, IDEA_KEY_SCHEDULE *ks, unsigned char *iv,
22                       int encrypt)
23 {
24     register unsigned long tin0, tin1;
25     register unsigned long tout0, tout1, xor0, xor1;
26     register long l = length;
27     unsigned long tin[2];
28 
29     if (encrypt) {
30         n2l(iv, tout0);
31         n2l(iv, tout1);
32         iv -= 8;
33         for (l -= 8; l >= 0; l -= 8) {
34             n2l(in, tin0);
35             n2l(in, tin1);
36             tin0 ^= tout0;
37             tin1 ^= tout1;
38             tin[0] = tin0;
39             tin[1] = tin1;
40             IDEA_encrypt(tin, ks);
41             tout0 = tin[0];
42             l2n(tout0, out);
43             tout1 = tin[1];
44             l2n(tout1, out);
45         }
46         if (l != -8) {
47             n2ln(in, tin0, tin1, l + 8);
48             tin0 ^= tout0;
49             tin1 ^= tout1;
50             tin[0] = tin0;
51             tin[1] = tin1;
52             IDEA_encrypt(tin, ks);
53             tout0 = tin[0];
54             l2n(tout0, out);
55             tout1 = tin[1];
56             l2n(tout1, out);
57         }
58         l2n(tout0, iv);
59         l2n(tout1, iv);
60     } else {
61         n2l(iv, xor0);
62         n2l(iv, xor1);
63         iv -= 8;
64         for (l -= 8; l >= 0; l -= 8) {
65             n2l(in, tin0);
66             tin[0] = tin0;
67             n2l(in, tin1);
68             tin[1] = tin1;
69             IDEA_encrypt(tin, ks);
70             tout0 = tin[0] ^ xor0;
71             tout1 = tin[1] ^ xor1;
72             l2n(tout0, out);
73             l2n(tout1, out);
74             xor0 = tin0;
75             xor1 = tin1;
76         }
77         if (l != -8) {
78             n2l(in, tin0);
79             tin[0] = tin0;
80             n2l(in, tin1);
81             tin[1] = tin1;
82             IDEA_encrypt(tin, ks);
83             tout0 = tin[0] ^ xor0;
84             tout1 = tin[1] ^ xor1;
85             l2nn(tout0, tout1, out, l + 8);
86             xor0 = tin0;
87             xor1 = tin1;
88         }
89         l2n(xor0, iv);
90         l2n(xor1, iv);
91     }
92     tin0 = tin1 = tout0 = tout1 = xor0 = xor1 = 0;
93     tin[0] = tin[1] = 0;
94 }
95 
IDEA_encrypt(unsigned long * d,IDEA_KEY_SCHEDULE * key)96 void IDEA_encrypt(unsigned long *d, IDEA_KEY_SCHEDULE *key)
97 {
98     register IDEA_INT *p;
99     register unsigned long x1, x2, x3, x4, t0, t1, ul;
100 
101     x2 = d[0];
102     x1 = (x2 >> 16);
103     x4 = d[1];
104     x3 = (x4 >> 16);
105 
106     p = &(key->data[0][0]);
107 
108     E_IDEA(0);
109     E_IDEA(1);
110     E_IDEA(2);
111     E_IDEA(3);
112     E_IDEA(4);
113     E_IDEA(5);
114     E_IDEA(6);
115     E_IDEA(7);
116 
117     x1 &= 0xffff;
118     idea_mul(x1, x1, *p, ul);
119     p++;
120 
121     t0 = x3 + *(p++);
122     t1 = x2 + *(p++);
123 
124     x4 &= 0xffff;
125     idea_mul(x4, x4, *p, ul);
126 
127     d[0] = (t0 & 0xffff) | ((x1 & 0xffff) << 16);
128     d[1] = (x4 & 0xffff) | ((t1 & 0xffff) << 16);
129 }
130