/src/openssl30/crypto/cast/c_cfb64.c
Line | Count | Source (jump to first uncovered line) |
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 | | * CAST low level APIs are deprecated for public use, but still ok for |
12 | | * internal use. |
13 | | */ |
14 | | #include "internal/deprecated.h" |
15 | | |
16 | | #include <openssl/cast.h> |
17 | | #include "cast_local.h" |
18 | | |
19 | | /* |
20 | | * The input and output encrypted as though 64bit cfb mode is being used. |
21 | | * The extra state information to record how much of the 64bit block we have |
22 | | * used is contained in *num; |
23 | | */ |
24 | | |
25 | | void CAST_cfb64_encrypt(const unsigned char *in, unsigned char *out, |
26 | | long length, const CAST_KEY *schedule, |
27 | | unsigned char *ivec, int *num, int enc) |
28 | 0 | { |
29 | 0 | register CAST_LONG v0, v1, t; |
30 | 0 | register int n = *num; |
31 | 0 | register long l = length; |
32 | 0 | CAST_LONG ti[2]; |
33 | 0 | unsigned char *iv, c, cc; |
34 | |
|
35 | 0 | iv = ivec; |
36 | 0 | if (enc) { |
37 | 0 | while (l--) { |
38 | 0 | if (n == 0) { |
39 | 0 | n2l(iv, v0); |
40 | 0 | ti[0] = v0; |
41 | 0 | n2l(iv, v1); |
42 | 0 | ti[1] = v1; |
43 | 0 | CAST_encrypt((CAST_LONG *)ti, schedule); |
44 | 0 | iv = ivec; |
45 | 0 | t = ti[0]; |
46 | 0 | l2n(t, iv); |
47 | 0 | t = ti[1]; |
48 | 0 | l2n(t, iv); |
49 | 0 | iv = ivec; |
50 | 0 | } |
51 | 0 | c = *(in++) ^ iv[n]; |
52 | 0 | *(out++) = c; |
53 | 0 | iv[n] = c; |
54 | 0 | n = (n + 1) & 0x07; |
55 | 0 | } |
56 | 0 | } else { |
57 | 0 | while (l--) { |
58 | 0 | if (n == 0) { |
59 | 0 | n2l(iv, v0); |
60 | 0 | ti[0] = v0; |
61 | 0 | n2l(iv, v1); |
62 | 0 | ti[1] = v1; |
63 | 0 | CAST_encrypt((CAST_LONG *)ti, schedule); |
64 | 0 | iv = ivec; |
65 | 0 | t = ti[0]; |
66 | 0 | l2n(t, iv); |
67 | 0 | t = ti[1]; |
68 | 0 | l2n(t, iv); |
69 | 0 | iv = ivec; |
70 | 0 | } |
71 | 0 | cc = *(in++); |
72 | 0 | c = iv[n]; |
73 | 0 | iv[n] = cc; |
74 | 0 | *(out++) = c ^ cc; |
75 | 0 | n = (n + 1) & 0x07; |
76 | 0 | } |
77 | 0 | } |
78 | 0 | v0 = v1 = ti[0] = ti[1] = t = c = cc = 0; |
79 | 0 | *num = n; |
80 | 0 | } |