1 /*
2 * Copyright 1995-2021 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
20 /*
21 * The input and output encrypted as though 64bit cfb mode is being used.
22 * The extra state information to record how much of the 64bit block we have
23 * used is contained in *num;
24 */
25
IDEA_cfb64_encrypt(const unsigned char * in,unsigned char * out,long length,IDEA_KEY_SCHEDULE * schedule,unsigned char * ivec,int * num,int encrypt)26 void IDEA_cfb64_encrypt(const unsigned char *in, unsigned char *out,
27 long length, IDEA_KEY_SCHEDULE *schedule,
28 unsigned char *ivec, int *num, int encrypt)
29 {
30 register unsigned long v0, v1, t;
31 register int n = *num;
32 register long l = length;
33 unsigned long ti[2];
34 unsigned char *iv, c, cc;
35
36 if (n < 0) {
37 *num = -1;
38 return;
39 }
40
41 iv = (unsigned char *)ivec;
42 if (encrypt) {
43 while (l--) {
44 if (n == 0) {
45 n2l(iv, v0);
46 ti[0] = v0;
47 n2l(iv, v1);
48 ti[1] = v1;
49 IDEA_encrypt((unsigned long *)ti, schedule);
50 iv = (unsigned char *)ivec;
51 t = ti[0];
52 l2n(t, iv);
53 t = ti[1];
54 l2n(t, iv);
55 iv = (unsigned char *)ivec;
56 }
57 c = *(in++) ^ iv[n];
58 *(out++) = c;
59 iv[n] = c;
60 n = (n + 1) & 0x07;
61 }
62 } else {
63 while (l--) {
64 if (n == 0) {
65 n2l(iv, v0);
66 ti[0] = v0;
67 n2l(iv, v1);
68 ti[1] = v1;
69 IDEA_encrypt((unsigned long *)ti, schedule);
70 iv = (unsigned char *)ivec;
71 t = ti[0];
72 l2n(t, iv);
73 t = ti[1];
74 l2n(t, iv);
75 iv = (unsigned char *)ivec;
76 }
77 cc = *(in++);
78 c = iv[n];
79 iv[n] = cc;
80 *(out++) = c ^ cc;
81 n = (n + 1) & 0x07;
82 }
83 }
84 v0 = v1 = ti[0] = ti[1] = t = c = cc = 0;
85 *num = n;
86 }
87
