llbase32.cpp
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- /**
- * @file llbase32.cpp
- * @brief base32 encoding that returns a std::string
- * @author James Cook
- *
- * Based on code from bitter
- * http://ghostwhitecrab.com/bitter/
- *
- * Some parts of this file are:
- * $LicenseInfo:firstyear=2007&license=viewergpl$
- *
- * Copyright (c) 2007-2010, Linden Research, Inc.
- *
- * Second Life Viewer Source Code
- * The source code in this file ("Source Code") is provided by Linden Lab
- * to you under the terms of the GNU General Public License, version 2.0
- * ("GPL"), unless you have obtained a separate licensing agreement
- * ("Other License"), formally executed by you and Linden Lab. Terms of
- * the GPL can be found in doc/GPL-license.txt in this distribution, or
- * online at http://secondlifegrid.net/programs/open_source/licensing/gplv2
- *
- * There are special exceptions to the terms and conditions of the GPL as
- * it is applied to this Source Code. View the full text of the exception
- * in the file doc/FLOSS-exception.txt in this software distribution, or
- * online at
- * http://secondlifegrid.net/programs/open_source/licensing/flossexception
- *
- * By copying, modifying or distributing this software, you acknowledge
- * that you have read and understood your obligations described above,
- * and agree to abide by those obligations.
- *
- * ALL LINDEN LAB SOURCE CODE IS PROVIDED "AS IS." LINDEN LAB MAKES NO
- * WARRANTIES, EXPRESS, IMPLIED OR OTHERWISE, REGARDING ITS ACCURACY,
- * COMPLETENESS OR PERFORMANCE.
- * $/LicenseInfo$
- */
- /**
- * Copyright (c) 2006 Christian Biere <christianbiere@gmx.de>
- * 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 authors 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 AUTHORS 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 REGENTS 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 "linden_common.h"
- #include "llbase32.h"
- #include <string>
- // bitter - base32.c starts here
- /*
- * See RFC 3548 for details about Base 32 encoding:
- * http://www.faqs.org/rfcs/rfc3548.html
- */
- static const char base32_alphabet[32] = {
- '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', '2', '3', '4', '5', '6', '7'
- };
- size_t
- base32_encode(char *dst, size_t size, const void *data, size_t len)
- {
- size_t i = 0;
- const U8 *p = (const U8*)data;
- const char *end = &dst[size];
- char *q = dst;
- do {
- size_t j, k;
- U8 x[5];
- char s[8];
- switch (len - i) {
- case 4: k = 7; break;
- case 3: k = 5; break;
- case 2: k = 3; break;
- case 1: k = 2; break;
- default:
- k = 8;
- }
- for (j = 0; j < 5; j++)
- x[j] = i < len ? p[i++] : 0;
- /*
- +-------+-----------+--------+
- | target| source | source |
- | byte | bits | byte |
- +-------+-----------+--------+
- | 0 | 7 6 5 4 3 | 0 |
- | 1 | 2 1 0 7 6 | 0-1 |
- | 2 | 5 4 3 2 1 | 1 |
- | 3 | 0 7 6 5 4 | 1-2 |
- | 4 | 3 2 1 0 7 | 2-3 |
- | 5 | 6 5 4 3 2 | 3 |
- | 6 | 1 0 7 6 5 | 3-4 |
- | 7 | 4 3 2 1 0 | 4 |
- +-------+-----------+--------+
-
- */
-
- s[0] = (x[0] >> 3);
- s[1] = ((x[0] & 0x07) << 2) | (x[1] >> 6);
- s[2] = (x[1] >> 1) & 0x1f;
- s[3] = ((x[1] & 0x01) << 4) | (x[2] >> 4);
- s[4] = ((x[2] & 0x0f) << 1) | (x[3] >> 7);
- s[5] = (x[3] >> 2) & 0x1f;
- s[6] = ((x[3] & 0x03) << 3) | (x[4] >> 5);
- s[7] = x[4] & 0x1f;
- for (j = 0; j < k && q != end; j++)
- *q++ = base32_alphabet[(U8) s[j]];
- } while (i < len);
- return q - dst;
- }
- /* *TODO: Implement base32 encode.
- static inline int
- ascii_toupper(int c)
- {
- return c >= 97 && c <= 122 ? c - 32 : c;
- }
- static inline int
- ascii_tolower(int c)
- {
- return c >= 65 && c <= 90 ? c + 32 : c;
- }
- static char base32_map[(unsigned char) -1];
- size_t
- base32_decode(char *dst, size_t size, const void *data, size_t len)
- {
- const char *end = &dst[size];
- const unsigned char *p = data;
- char *q = dst;
- size_t i;
- unsigned max_pad = 3;
- if (0 == base32_map[0]) {
- for (i = 0; i < LL_ARRAY_SIZE(base32_map); i++) {
- const char *x;
-
- x = memchr(base32_alphabet, ascii_toupper(i), sizeof base32_alphabet);
- base32_map[i] = x ? (x - base32_alphabet) : (unsigned char) -1;
- }
- }
-
- for (i = 0; i < len && max_pad > 0; i++) {
- unsigned char c;
- char s[8];
- size_t j;
- c = p[i];
- if ('=' == c) {
- max_pad--;
- c = 0;
- } else {
- c = base32_map[c];
- if ((unsigned char) -1 == c) {
- return -1;
- }
- }
- j = i % LL_ARRAY_SIZE(s);
- s[j] = c;
- if (7 == j) {
- char b[5];
- b[0] = ((s[0] << 3) & 0xf8) | ((s[1] >> 2) & 0x07);
- b[1] = ((s[1] & 0x03) << 6) | ((s[2] & 0x1f) << 1) | ((s[3] >> 4) & 1);
- b[2] = ((s[3] & 0x0f) << 4) | ((s[4] >> 1) & 0x0f);
- b[3] = ((s[4] & 1) << 7) | ((s[5] & 0x1f) << 2) | ((s[6] >> 3) & 0x03);
- b[4] = ((s[6] & 0x07) << 5) | (s[7] & 0x1f);
- for (j = 0; j < LL_ARRAY_SIZE(b); j++) {
- if (q != end)
- *q = b[j];
- q++;
- }
- }
- }
- return q - dst;
- }
- */
- // The following is
- // Copyright (c) 2007-$CurrentYear$, Linden Research, Inc.
- // static
- std::string LLBase32::encode(const U8* input, size_t input_size)
- {
- std::string output;
- if (input)
- {
- // Each 5 byte chunk of input is represented by an
- // 8 byte chunk of output.
- size_t input_chunks = (input_size + 4) / 5;
- size_t output_size = input_chunks * 8;
- output.resize(output_size);
- size_t encoded = base32_encode(&output[0], output_size, input, input_size);
- llinfos << "encoded " << encoded << " into buffer of size "
- << output_size << llendl;
- }
- return output;
- }