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Joseph Sutton a18436d709 roken: Remove excess zeros in literals
Signed-off-by: Joseph Sutton <josephsutton@catalyst.net.nz>
2023-11-02 20:19:54 -05:00

314 lines
9.2 KiB
C

/*
* Copyright (c) 2020 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 "base32.h"
#include "roken.h"
static const unsigned char base32_chars[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZ234567";
static const unsigned char base32op_chars[] = "0123456789ABCDEFGHIJKLMNOPQRSTUV";
ROKEN_LIB_FUNCTION int ROKEN_LIB_CALL
rk_base32_encode(const void *data, int size, char **str, enum rk_base32_flags flags)
{
const unsigned char *chars =
(flags & RK_BASE32_FLAG_PRESERVE_ORDER) ? base32op_chars :
base32_chars;
uint64_t c;
char *s, *p;
int i;
const unsigned char *q;
if (size > INT_MAX/8 || size < 0) {
*str = NULL;
errno = ERANGE;
return -1;
}
p = s = malloc(((size + 5 - 1) / 5) * 8 + 1);
if (p == NULL) {
*str = NULL;
return -1;
}
q = (const unsigned char *) data;
for (i = 0; i < size;) {
/* 5 bytes of input will give us 8 output bytes' worth of bits */
c = q[i++];
c <<= 8;
if (i < size)
c += q[i];
i++;
c <<= 8;
if (i < size)
c += q[i];
i++;
c <<= 8;
if (i < size)
c += q[i];
i++;
c <<= 8;
if (i < size)
c += q[i];
i++;
p[0] = chars[(c & 0x000000f800000000ULL) >> 35];
p[1] = chars[(c & 0x00000007c0000000ULL) >> 30];
p[2] = chars[(c & 0x000000003e000000ULL) >> 25];
p[3] = chars[(c & 0x0000000001f00000ULL) >> 20];
p[4] = chars[(c & 0x00000000000f8000ULL) >> 15];
p[5] = chars[(c & 0x0000000000007c00ULL) >> 10];
p[6] = chars[(c & 0x00000000000003e0ULL) >> 5];
p[7] = chars[(c & 0x000000000000001fULL) >> 0];
switch (i - size) {
case 4: p[2] = p[3] = '='; HEIM_FALLTHROUGH;
case 3: p[4] = '='; HEIM_FALLTHROUGH;
case 2: p[5] = p[6] = '='; HEIM_FALLTHROUGH;
case 1: p[7] = '='; HEIM_FALLTHROUGH;
default: break;
}
p += 8;
}
*p = 0;
*str = s;
return (int) strlen(s);
}
#define DECODE_ERROR ((uint64_t)-1)
static int
pos(char c, int preserve_order)
{
/* EBCDIC need not apply */
if (preserve_order) {
if (c >= '0' && c <= '9')
return c - '0';
if (c >= 'A' && c <= 'V')
return c - 'A' + ('9' - '0') + 1;
} else {
if (c >= 'A' && c <= 'Z')
return c - 'A';
if (c >= '2' && c <= '7')
return c - '2' + ('Z' - 'A') + 1;
}
return -1;
}
static uint64_t
token_decode(const char *token, enum rk_base32_flags flags)
{
uint64_t marker = 0;
uint64_t val = 0;
int preserve_order = !!(flags & RK_BASE32_FLAG_PRESERVE_ORDER);
int i, c;
for (i = 0; i < 8 && token[i] != '\0'; i++) {
val <<= 5;
if (token[i] == '=')
marker++;
else if (marker)
return DECODE_ERROR;
else if ((c = pos(token[i], preserve_order)) == -1 &&
(flags & RK_BASE32_FLAG_STOP_ON_GARBAGE))
break;
else if (c == -1)
return DECODE_ERROR;
else
val |= c;
}
if (i < 8 || marker > 6)
return DECODE_ERROR;
return (marker << 40) | val;
}
ROKEN_LIB_FUNCTION int ROKEN_LIB_CALL
rk_base32_decode(const char *str, void *data, enum rk_base32_flags flags)
{
const char *p;
unsigned char *q;
int preserve_order = !!(flags & RK_BASE32_FLAG_PRESERVE_ORDER);
q = data;
for (p = str; *p && (*p == '=' || pos(*p, preserve_order) != -1); p += 8) {
uint64_t val = token_decode(p, flags);
uint64_t marker = (val >> 40) & 0xffULL;
if (val == DECODE_ERROR) {
errno = EINVAL;
return -1;
}
*q++ = (val >> 32) & 0xffULL;
if (marker < 6)
*q++ = (val >> 24) & 0xffULL;
if (marker < 4)
*q++ = (val >> 16) & 0xffULL;
if (marker < 3)
*q++ = (val >> 8) & 0xffULL;
if (marker < 1)
*q++ = val & 0xffULL;
if (marker && !(flags & RK_BASE32_FLAG_INTERIOR_PADDING_OK))
break;
}
if (q - (unsigned char *) data > INT_MAX) {
errno = EOVERFLOW;
return -1;
}
return q - (unsigned char *) data;
}
#ifdef TEST
static int interior_padding_ok;
static int preserve_order_flag;
static int stop_on_garbage;
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[] = {
{ "preserve-order", 'P', arg_flag, &preserve_order_flag,
"Use order-preserving alphabet", NULL },
{ "interior-padding-ok", 'O', arg_flag, &interior_padding_ok,
"Decode concatenated padded base32 strings as one", NULL },
{ "stop-on-garbage", 'G', arg_flag, &stop_on_garbage,
"Do not error on garbage", NULL },
{ "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)
{
enum rk_base32_flags flags = 0;
unsigned char *buf = NULL;
size_t buflen = 0;
size_t bufsz = 0;
int goptind = 0;
int ret;
setprogname("rkbase32");
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;
flags |= preserve_order_flag ? RK_BASE32_FLAG_PRESERVE_ORDER : 0;
flags |= interior_padding_ok ? RK_BASE32_FLAG_INTERIOR_PADDING_OK : 0;
flags |= stop_on_garbage ? RK_BASE32_FLAG_STOP_ON_GARBAGE : 0;
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 * 5 / 8 + 4)) == NULL)
err(1, "Could not decode data");
if ((ret = rk_base32_decode((const char *)buf, d, flags)) < 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_base32_encode(buf, buflen, &e, flags)) < 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