xref: /freebsd/lib/libcrypt/misc.c (revision 3f0164abf32b9b761e0a2cb4bdca3a8b84f156d4)
1 /*
2  * Copyright (c) 1999
3  *      University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. Neither the name of the author nor the names of any co-contributors
14  *    may be used to endorse or promote products derived from this software
15  *    without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY CONTRIBUTORS ``AS IS'' AND ANY EXPRESS
18  * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
19  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED. IN NO EVENT SHALL CONTRIBUTORS BE LIABLE FOR ANY
21  * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
23  * GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
24  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
25  * IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
26  * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN
27  * IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28  */
29 
30 #include <sys/cdefs.h>
31 __FBSDID("$FreeBSD$");
32 
33 #include <sys/types.h>
34 
35 #include "crypt.h"
36 
37 static char itoa64[] =		/* 0 ... 63 => ascii - 64 */
38 	"./0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";
39 
40 void
41 _crypt_to64(char *s, u_long v, int n)
42 {
43 	while (--n >= 0) {
44 		*s++ = itoa64[v&0x3f];
45 		v >>= 6;
46 	}
47 }
48 
49 void
50 b64_from_24bit(uint8_t B2, uint8_t B1, uint8_t B0, int n, int *buflen, char **cp)
51 {
52 	uint32_t w;
53 	int i;
54 
55 	w = (B2 << 16) | (B1 << 8) | B0;
56 	for (i = 0; i < n; i++) {
57 		**cp = itoa64[w&0x3f];
58 		(*cp)++;
59 		if ((*buflen)-- < 0)
60 			break;
61 		w >>= 6;
62 	}
63 }
64