/* $Id: armor.c,v 1.2 2004/12/31 23:47:47 dm Exp $ */
/*
*
* Copyright (C) 1999 David Mazieres (dm@uun.org)
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2, or (at
* your option) any later version.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
* USA
*
*/
#include "avutil.h"
static const char b2a32[32] = {
'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h',
'i', 'j', 'k', 'm', 'n', 'p', 'q', 'r',
's', 't', 'u', 'v', 'w', 'x', 'y', 'z',
'2', '3', '4', '5', '6', '7', '8', '9',
};
static const signed char a2b32[256] = {
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, 24, 25, 26, 27, 28, 29, 30, 31, -1, -1, -1, -1, -1, -1,
-1, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, -1, 11, 12, -1,
13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, -1, -1, -1, -1, -1,
-1, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, -1, 11, 12, -1,
13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
};
static const int b2a32rem[5] = {0, 2, 4, 5, 7};
static const int a2b32rem[8] = {0, -1, 1, -1, 2, 3, -1, 4};
/* 0 1 2 3 4 5 6 7
* 0 5 3
* 1 2 5 1
* 2 4 4
* 3 1 5 2
* 4 3 5
*/
char *
armor32 (const void *dp, size_t dl)
{
const u_char *p = dp;
int rem = dl % 5;
const u_char *e = p + (dl - rem);
size_t reslen = (dl / 5) * 8 + b2a32rem[rem];
char *res = malloc (reslen + 1);
char *d = res;
if (!res)
return NULL;
while (p < e) {
d[0] = b2a32[p[0] >> 3];
d[1] = b2a32[(p[0] & 0x7) << 2 | p[1] >> 6];
d[2] = b2a32[p[1] >> 1 & 0x1f];
d[3] = b2a32[(p[1] & 0x1) << 4 | p[2] >> 4];
d[4] = b2a32[(p[2] & 0xf) << 1 | p[3] >> 7];
d[5] = b2a32[p[3] >> 2 & 0x1f];
d[6] = b2a32[(p[3] & 0x3) << 3 | p[4] >> 5];
d[7] = b2a32[p[4] & 0x1f];
p += 5;
d += 8;
}
switch (rem) {
case 4:
d[6] = b2a32[(p[3] & 0x3) << 3];
d[5] = b2a32[p[3] >> 2 & 0x1f];
d[4] = b2a32[(p[2] & 0xf) << 1 | p[3] >> 7];
d[3] = b2a32[(p[1] & 0x1) << 4 | p[2] >> 4];
d[2] = b2a32[p[1] >> 1 & 0x1f];
d[1] = b2a32[(p[0] & 0x7) << 2 | p[1] >> 6];
d[0] = b2a32[p[0] >> 3];
d += 7;
break;
case 3:
d[4] = b2a32[(p[2] & 0xf) << 1];
d[3] = b2a32[(p[1] & 0x1) << 4 | p[2] >> 4];
d[2] = b2a32[p[1] >> 1 & 0x1f];
d[1] = b2a32[(p[0] & 0x7) << 2 | p[1] >> 6];
d[0] = b2a32[p[0] >> 3];
d += 5;
break;
case 2:
d[3] = b2a32[(p[1] & 0x1) << 4];
d[2] = b2a32[p[1] >> 1 & 0x1f];
d[1] = b2a32[(p[0] & 0x7) << 2 | p[1] >> 6];
d[0] = b2a32[p[0] >> 3];
d += 4;
break;
case 1:
d[1] = b2a32[(p[0] & 0x7) << 2];
d[0] = b2a32[p[0] >> 3];
d += 2;
break;
}
assert (d == res + reslen);
*d = '\0';
return res;
}
ssize_t
armor32len (const char *_s)
{
const u_char *s = (const u_char *) _s;
const u_char *p = s;
ssize_t len;
while (a2b32[*p] >= 0)
p++;
len = p - s;
return a2b32rem[len & 7] < 0 ? -1 : len;
}
ssize_t
dearmor32len (const char *s)
{
ssize_t len = armor32len (s);
return len < 0 ? -1 : (len >> 3) * 5 + a2b32rem[len & 7];
}
ssize_t
dearmor32 (void *out, const char *_s)
{
const u_char *s = (const u_char *) _s;
ssize_t len = armor32len (_s);
int rem = a2b32rem [len & 7];
size_t outlen = (len >> 3) * 5 + rem;
char *d = out;
int c0, c1, c2, c3, c4, c5, c6, c7;
const u_char *e;
if (rem < 0)
return -1;
if (len <= 0)
return 0;
for (e = s + (len & ~7); s < e; s += 8, d += 5) {
c0 = a2b32[s[0]];
c1 = a2b32[s[1]];
d[0] = c0 << 3 | c1 >> 2;
c2 = a2b32[s[2]];
c3 = a2b32[s[3]];
d[1] = c1 << 6 | c2 << 1 | c3 >> 4;
c4 = a2b32[s[4]];
d[2] = c3 << 4 | c4 >> 1;
c5 = a2b32[s[5]];
c6 = a2b32[s[6]];
d[3] = c4 << 7 | c5 << 2 | c6 >> 3;
c7 = a2b32[s[7]];
d[4] = c6 << 5 | c7;
}
if (rem >= 1) {
c0 = a2b32[s[0]];
c1 = a2b32[s[1]];
*d++ = c0 << 3 | c1 >> 2;
if (rem >= 2) {
c2 = a2b32[s[2]];
c3 = a2b32[s[3]];
*d++ = c1 << 6 | c2 << 1 | c3 >> 4;
if (rem >= 3) {
c4 = a2b32[s[4]];
*d++ = c3 << 4 | c4 >> 1;
if (rem >= 4) {
c5 = a2b32[s[5]];
c6 = a2b32[s[6]];
*d++ = c4 << 7 | c5 << 2 | c6 >> 3;
}
}
}
}
assert (d == (char *) out + outlen);
return len;
}
static const char b2a64[64] = {
'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H',
'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P',
'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X',
'Y', 'Z', 'a', 'b', 'c', 'd', 'e', 'f',
'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n',
'o', 'p', 'q', 'r', 's', 't', 'u', 'v',
'w', 'x', 'y', 'z', '0', '1', '2', '3',
'4', '5', '6', '7', '8', '9', '+', '/',
};
static const signed char a2b64[256] = {
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, 62, -1, -1, -1, 63,
52, 53, 54, 55, 56, 57, 58, 59, 60, 61, -1, -1, -1, -1, -1, -1,
-1, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14,
15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, -1, -1, -1, -1, -1,
-1, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,
41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
};
char *
armor64 (const void *dp, size_t len)
{
const u_char *p = dp;
int rem = len % 3;
const u_char *e = p + (len - rem);
size_t reslen = ((len + 2) / 3) * 4;
char *res = malloc (reslen + 1);
char *d = res;
while (p < e) {
d[0] = b2a64[p[0] >> 2];
d[1] = b2a64[(p[0] & 0x3) << 4 | p[1] >> 4];
d[2] = b2a64[(p[1] & 0xf) << 2 | p[2] >> 6];
d[3] = b2a64[p[2] & 0x3f];
d += 4;
p += 3;
}
switch (rem) {
case 1:
d[0] = b2a64[p[0] >> 2];
d[1] = b2a64[(p[0] & 0x3) << 4];
d[2] = d[3] = '=';
d += 4;
break;
case 2:
d[0] = b2a64[p[0] >> 2];
d[1] = b2a64[(p[0] & 0x3) << 4 | p[1] >> 4];
d[2] = b2a64[(p[1] & 0xf) << 2];
d[3] = '=';
d += 4;
break;
}
assert (d == res + reslen);
*d = '\0';
return res;
}
ssize_t
armor64len (const char *_s)
{
const u_char *s = (const u_char *) _s;
const u_char *p = s;
ssize_t len;
while (a2b64[*p] >= 0)
p++;
if (*p == '=')
p++;
if (*p == '=')
p++;
len = p - s;
return (len & 3) ? -1 : len;
}
ssize_t
dearmor64len (const char *_s)
{
const u_char *s = (const u_char *) _s;
const u_char *p = s;
ssize_t len;
while (a2b64[*p] >= 0)
p++;
len = p - s;
switch (len & 3) {
case 0:
return (len >> 2) * 3;
case 2:
return p[0] == '=' && p[1] == '=' ? (len >> 2) * 3 + 1 : -1;
case 3:
return p[0] == '=' ? (len >> 2) * 3 + 2 : -1;
}
return -1;
}
ssize_t
dearmor64 (void *out, const char *_s)
{
const u_char *s = (const u_char *) _s;
ssize_t outlen = dearmor64len (_s);
ssize_t len = ((outlen + 2) / 3) * 4;
char *d = out;
int c0, c1, c2, c3;
const u_char *e;
if (outlen < 0)
return -1;
if (len <= 0)
return len;
for (e = s + len - 4; s < e; s += 4, d += 3) {
c0 = a2b64[s[0]];
c1 = a2b64[s[1]];
d[0] = c0 << 2 | c1 >> 4;
c2 = a2b64[s[2]];
d[1] = c1 << 4 | c2 >> 2;
c3 = a2b64[s[3]];
d[2] = c2 << 6 | c3;
}
c0 = a2b64[s[0]];
c1 = a2b64[s[1]];
*d++ = c0 << 2 | c1 >> 4;
if ((c2 = a2b64[s[2]]) >= 0) {
*d++ = c1 << 4 | c2 >> 2;
if ((c3 = a2b64[s[3]]) >= 0)
*d++ = c2 << 6 | c3;
}
*d = '\0';
return len;
}
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