1 /* $OpenBSD: radius_subr.c,v 1.1 2024/07/14 15:31:49 yasuoka Exp $ */
2
3 /*
4 * Copyright (c) 2013, 2023 Internet Initiative Japan Inc.
5 *
6 * Permission to use, copy, modify, and distribute this software for any
7 * purpose with or without fee is hereby granted, provided that the above
8 * copyright notice and this permission notice appear in all copies.
9 *
10 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
11 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
13 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
14 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
15 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
16 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17 */
18
19 #include <sys/types.h>
20
21 #include <md5.h>
22 #include <string.h>
23
24 #include "radius_subr.h"
25
26 void
radius_attr_hide(const char * secret,const char * authenticator,const u_char * salt,u_char * plain,int plainlen)27 radius_attr_hide(const char *secret, const char *authenticator,
28 const u_char *salt, u_char *plain, int plainlen)
29 {
30 int i, j;
31 u_char b[16];
32 MD5_CTX md5ctx;
33
34 i = 0;
35 do {
36 MD5Init(&md5ctx);
37 MD5Update(&md5ctx, secret, strlen(secret));
38 if (i == 0) {
39 MD5Update(&md5ctx, authenticator, 16);
40 if (salt != NULL)
41 MD5Update(&md5ctx, salt, 2);
42 } else
43 MD5Update(&md5ctx, plain + i - 16, 16);
44 MD5Final(b, &md5ctx);
45
46 for (j = 0; j < 16 && i < plainlen; i++, j++)
47 plain[i] ^= b[j];
48 } while (i < plainlen);
49 }
50
51 void
radius_attr_unhide(const char * secret,const char * authenticator,const u_char * salt,u_char * crypt0,int crypt0len)52 radius_attr_unhide(const char *secret, const char *authenticator,
53 const u_char *salt, u_char *crypt0, int crypt0len)
54 {
55 int i, j;
56 u_char b[16];
57 MD5_CTX md5ctx;
58
59 i = 16 * ((crypt0len - 1) / 16);
60 while (i >= 0) {
61 MD5Init(&md5ctx);
62 MD5Update(&md5ctx, secret, strlen(secret));
63 if (i == 0) {
64 MD5Update(&md5ctx, authenticator, 16);
65 if (salt != NULL)
66 MD5Update(&md5ctx, salt, 2);
67 } else
68 MD5Update(&md5ctx, crypt0 + i - 16, 16);
69 MD5Final(b, &md5ctx);
70
71 for (j = 0; j < 16 && i + j < crypt0len; j++)
72 crypt0[i + j] ^= b[j];
73 i -= 16;
74 }
75 }
76