Files
2023-01-04 00:43:35 -06:00

271 lines
7.1 KiB
C

/*
* Copyright (c) 1995-2001 Kungliga Tekniska Högskolan
* (Royal Institute of Technology, Stockholm, Sweden).
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* 3. Neither the name of the Institute nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <config.h>
#include <errno.h>
#include <stdlib.h>
#include <string.h>
#include <limits.h>
#ifdef TEST
#include <stdio.h>
#include <getarg.h>
#include <err.h>
#endif
#include "base64.h"
#include "roken.h"
#define base64_chars "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"
static int
pos(char c)
{
#if 'A' == '\301'
const char *p;
for (p = base64_chars; *p; p++)
if (*p == c)
return p - base64_chars;
return -1;
#else
if (c >= 'A' && c <= 'Z')
return c - 'A';
if (c >= 'a' && c <= 'z')
return ('Z' + 1 - 'A') + c - 'a';
if (c >= '0' && c <= '9')
return ('Z' + 1 - 'A') +
('z' + 1 - 'a') + c - '0';
if (c == '+')
return 62;
if (c == '/')
return 63;
return -1;
#endif
}
ROKEN_LIB_FUNCTION int ROKEN_LIB_CALL
rk_base64_encode(const void *data, int size, char **str)
{
char *s, *p;
int i;
int c;
const unsigned char *q;
if (size > INT_MAX/4 || size < 0) {
*str = NULL;
errno = ERANGE;
return -1;
}
p = s = (char *) malloc(size * 4 / 3 + 4);
if (p == NULL) {
*str = NULL;
return -1;
}
q = (const unsigned char *) data;
for (i = 0; i < size;) {
c = q[i++];
c *= 256;
if (i < size)
c += q[i];
i++;
c *= 256;
if (i < size)
c += q[i];
i++;
p[0] = base64_chars[(c & 0x00fc0000) >> 18];
p[1] = base64_chars[(c & 0x0003f000) >> 12];
p[2] = base64_chars[(c & 0x00000fc0) >> 6];
p[3] = base64_chars[(c & 0x0000003f) >> 0];
if (i > size)
p[3] = '=';
if (i > size + 1)
p[2] = '=';
p += 4;
}
*p = 0;
*str = s;
return (int) strlen(s);
}
#define DECODE_ERROR 0xffffffff
static unsigned int
token_decode(const char *token)
{
int i;
unsigned int val = 0;
int marker = 0;
for (i = 0; i < 4 && token[i] != '\0'; i++) {
val *= 64;
if (token[i] == '=')
marker++;
else if (marker > 0)
return DECODE_ERROR;
else
val += pos(token[i]);
}
if (i < 4 || marker > 2)
return DECODE_ERROR;
return (marker << 24) | val;
}
ROKEN_LIB_FUNCTION int ROKEN_LIB_CALL
rk_base64_decode(const char *str, void *data)
{
const char *p;
unsigned char *q;
q = data;
for (p = str; *p && (*p == '=' || pos(*p) != -1); p += 4) {
unsigned int val = token_decode(p);
unsigned int marker = (val >> 24) & 0xff;
if (val == DECODE_ERROR) {
errno = EINVAL;
return -1;
}
*q++ = (val >> 16) & 0xff;
if (marker < 2)
*q++ = (val >> 8) & 0xff;
if (marker < 1)
*q++ = val & 0xff;
}
if (q - (unsigned char *) data > INT_MAX) {
errno = EOVERFLOW;
return -1;
}
return q - (unsigned char *) data;
}
#ifdef TEST
static int decode_flag;
static int help_flag;
/*
* The short options are compatible with a subset of the FreeBSD contrib
* vis(1). Heimdal additions have long option names only.
*/
static struct getargs args[] = {
{ "decode", 'd', arg_flag, &decode_flag, "Decode", NULL },
{ "help", 'h', arg_flag, &help_flag, "Print help message", NULL },
};
static size_t num_args = sizeof(args)/sizeof(args[0]);
int
main(int argc, char **argv)
{
unsigned char *buf = NULL;
size_t buflen = 0;
size_t bufsz = 0;
int goptind = 0;
int ret;
setprogname("rkbase64");
if (getarg(args, num_args, argc, argv, &goptind) || help_flag) {
arg_printusage(args, num_args, NULL, "FILE | -");
return help_flag ? 0 : 1;
}
argc -= goptind;
argv += goptind;
if (help_flag)
return arg_printusage(args, num_args, NULL, "FILE | -- -"), 0;
if (argc != 1)
return arg_printusage(args, num_args, NULL, "FILE | -- -"), 1;
if (strcmp(argv[0], "-") == 0) {
unsigned char *tmp;
unsigned char d[4096];
size_t bytes;
while (!feof(stdin) && !ferror(stdin)) {
bytes = fread(d, 1, sizeof(d), stdin);
if (bytes == 0)
continue;
if (buflen + bytes > bufsz) {
if ((tmp = realloc(buf, bufsz + (bufsz >> 2) + sizeof(d))) == NULL)
err(1, "Could not read stdin");
buf = tmp;
bufsz = bufsz + (bufsz >> 2) + sizeof(d);
}
memcpy(buf + buflen, d, bytes);
buflen += bytes;
}
if (ferror(stdin))
err(1, "Could not read stdin");
} else {
void *d;
if ((errno = rk_undumpdata(argv[0], &d, &bufsz)))
err(1, "Could not read %s", argv[0]);
buflen = bufsz;
buf = d;
}
if (decode_flag) {
unsigned char *d;
if (buflen == bufsz) {
unsigned char *tmp;
if ((tmp = realloc(buf, bufsz + 1)) == NULL)
err(1, "Could not decode data");
buf = tmp;
bufsz++;
}
buf[buflen] = '\0';
if ((d = malloc(buflen * 3 / 4 + 4)) == NULL)
err(1, "Could not decode data");
if ((ret = rk_base64_decode((const char *)buf, d)) < 0)
err(1, "Could not decode data");
if (fwrite(d, ret, 1, stdout) != 1)
err(1, "Could not write decoded data");
free(d);
} else if (buf) { /* buf can be NULL if we read from an empty file */
char *e;
if ((ret = rk_base64_encode(buf, buflen, &e)) < 0)
err(1, "Could not encode data");
if (fwrite(e, ret, 1, stdout) != 1)
err(1, "Could not write decoded data");
free(e);
if (fwrite("\n", 1, 1, stdout) != 1)
err(1, "Could not write decoded data");
}
free(buf);
return 0;
}
#endif