/src/openssl/crypto/rc4/rc4_enc.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 | | * RC4 low level APIs are deprecated for public use, but still ok for internal |
12 | | * use. |
13 | | */ |
14 | | #include "internal/deprecated.h" |
15 | | |
16 | | #include <openssl/rc4.h> |
17 | | #include "rc4_local.h" |
18 | | |
19 | | /*- |
20 | | * RC4 as implemented from a posting from |
21 | | * Newsgroups: sci.crypt |
22 | | * Subject: RC4 Algorithm revealed. |
23 | | * Message-ID: <sternCvKL4B.Hyy@netcom.com> |
24 | | * Date: Wed, 14 Sep 1994 06:35:31 GMT |
25 | | */ |
26 | | |
27 | | void RC4(RC4_KEY *key, size_t len, const unsigned char *indata, |
28 | | unsigned char *outdata) |
29 | 0 | { |
30 | 0 | register RC4_INT *d; |
31 | 0 | register RC4_INT x, y, tx, ty; |
32 | 0 | size_t i; |
33 | |
|
34 | 0 | x = key->x; |
35 | 0 | y = key->y; |
36 | 0 | d = key->data; |
37 | |
|
38 | 0 | #define LOOP(in,out) \ |
39 | 0 | x=((x+1)&0xff); \ |
40 | 0 | tx=d[x]; \ |
41 | 0 | y=(tx+y)&0xff; \ |
42 | 0 | d[x]=ty=d[y]; \ |
43 | 0 | d[y]=tx; \ |
44 | 0 | (out) = d[(tx+ty)&0xff]^ (in); |
45 | |
|
46 | 0 | i = len >> 3; |
47 | 0 | if (i) { |
48 | 0 | for (;;) { |
49 | 0 | LOOP(indata[0], outdata[0]); |
50 | 0 | LOOP(indata[1], outdata[1]); |
51 | 0 | LOOP(indata[2], outdata[2]); |
52 | 0 | LOOP(indata[3], outdata[3]); |
53 | 0 | LOOP(indata[4], outdata[4]); |
54 | 0 | LOOP(indata[5], outdata[5]); |
55 | 0 | LOOP(indata[6], outdata[6]); |
56 | 0 | LOOP(indata[7], outdata[7]); |
57 | 0 | indata += 8; |
58 | 0 | outdata += 8; |
59 | 0 | if (--i == 0) |
60 | 0 | break; |
61 | 0 | } |
62 | 0 | } |
63 | 0 | i = len & 0x07; |
64 | 0 | if (i) { |
65 | 0 | for (;;) { |
66 | 0 | LOOP(indata[0], outdata[0]); |
67 | 0 | if (--i == 0) |
68 | 0 | break; |
69 | 0 | LOOP(indata[1], outdata[1]); |
70 | 0 | if (--i == 0) |
71 | 0 | break; |
72 | 0 | LOOP(indata[2], outdata[2]); |
73 | 0 | if (--i == 0) |
74 | 0 | break; |
75 | 0 | LOOP(indata[3], outdata[3]); |
76 | 0 | if (--i == 0) |
77 | 0 | break; |
78 | 0 | LOOP(indata[4], outdata[4]); |
79 | 0 | if (--i == 0) |
80 | 0 | break; |
81 | 0 | LOOP(indata[5], outdata[5]); |
82 | 0 | if (--i == 0) |
83 | 0 | break; |
84 | 0 | LOOP(indata[6], outdata[6]); |
85 | 0 | if (--i == 0) |
86 | 0 | break; |
87 | 0 | } |
88 | 0 | } |
89 | 0 | key->x = x; |
90 | 0 | key->y = y; |
91 | 0 | } |