cpukit/libcrypt/misc.c

0001 /*-
0002  * SPDX-License-Identifier: BSD-3-Clause
0003  *
0004  * Copyright (c) 1999
0005  *      University of California.  All rights reserved.
0006  *
0007  * Redistribution and use in source and binary forms, with or without
0008  * modification, are permitted provided that the following conditions
0009  * are met:
0010  * 1. Redistributions of source code must retain the above copyright
0011  *    notice, this list of conditions and the following disclaimer.
0012  * 2. Redistributions in binary form must reproduce the above copyright
0013  *    notice, this list of conditions and the following disclaimer in the
0014  *    documentation and/or other materials provided with the distribution.
0015  * 3. Neither the name of the author nor the names of any co-contributors
0016  *    may be used to endorse or promote products derived from this software
0017  *    without specific prior written permission.
0018  *
0019  * THIS SOFTWARE IS PROVIDED BY CONTRIBUTORS ``AS IS'' AND ANY EXPRESS
0020  * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
0021  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
0022  * ARE DISCLAIMED. IN NO EVENT SHALL CONTRIBUTORS BE LIABLE FOR ANY
0023  * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
0024  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
0025  * GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
0026  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
0027  * IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
0028  * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN
0029  * IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
0030  */
0031
0032 #include <sys/cdefs.h>
0033 __FBSDID("$FreeBSD$");
0034
0035 #include <sys/types.h>
0036
0037 #include <crypt.h>
0038
0039 static const char itoa64[] =        /* 0 ... 63 => ascii - 64 */
0040     "./0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";
0041
0042 void
0043 _crypt_to64(char *s, u_long v, int n)
0044 {
0045     while (--n >= 0) {
0046         *s++ = itoa64[v&0x3f];
0047         v >>= 6;
0048     }
0049 }
0050
0051 void
0052 b64_from_24bit(uint8_t B2, uint8_t B1, uint8_t B0, int n, int *buflen, char **cp)
0053 {
0054     uint32_t w;
0055     int i;
0056
0057 #if defined(__rtems__)
0058     w = ((uint32_t)B2 << 16) | ((uint32_t)B1 << 8) | B0;
0059 #else
0060     w = (B2 << 16) | (B1 << 8) | B0;
0061 #endif
0062     for (i = 0; i < n; i++) {
0063         **cp = itoa64[w&0x3f];
0064         (*cp)++;
0065         if ((*buflen)-- < 0)
0066             break;
0067         w >>= 6;
0068     }
0069 }