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googleanalytics / lib / analytics-admin / vendor / paragonie / constant_time_encoding / src / Base64UrlSafe.php

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Base32.php 3 years ago Base32Hex.php 3 years ago Base64.php 3 years ago Base64DotSlash.php 3 years ago Base64DotSlashOrdered.php 3 years ago Base64UrlSafe.php 3 years ago Binary.php 3 years ago EncoderInterface.php 3 years ago Encoding.php 3 years ago Hex.php 3 years ago RFC4648.php 3 years ago

Base64UrlSafe.php

96 lines

1	<?php
2	declare(strict_types=1);
3	namespace ParagonIE\ConstantTime;
4
5	/**
6	* Copyright (c) 2016 - 2022 Paragon Initiative Enterprises.
7	* Copyright (c) 2014 Steve "Sc00bz" Thomas (steve at tobtu dot com)
8	*
9	* Permission is hereby granted, free of charge, to any person obtaining a copy
10	* of this software and associated documentation files (the "Software"), to deal
11	* in the Software without restriction, including without limitation the rights
12	* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
13	* copies of the Software, and to permit persons to whom the Software is
14	* furnished to do so, subject to the following conditions:
15	*
16	* The above copyright notice and this permission notice shall be included in all
17	* copies or substantial portions of the Software.
18	*
19	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
20	* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
21	* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
22	* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
23	* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
24	* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
25	* SOFTWARE.
26	*/
27
28	/**
29	* Class Base64UrlSafe
30	* [A-Z][a-z][0-9]\-_
31	*
32	* @package ParagonIE\ConstantTime
33	*/
34	abstract class Base64UrlSafe extends Base64
35	{
36
37	/**
38	* Uses bitwise operators instead of table-lookups to turn 6-bit integers
39	* into 8-bit integers.
40	*
41	* Base64 character set:
42	* [A-Z] [a-z] [0-9] - _
43	* 0x41-0x5a, 0x61-0x7a, 0x30-0x39, 0x2d, 0x5f
44	*
45	* @param int $src
46	* @return int
47	*/
48	protected static function decode6Bits(int $src): int
49	{
50	$ret = -1;
51
52	// if ($src > 0x40 && $src < 0x5b) $ret += $src - 0x41 + 1; // -64
53	$ret += (((0x40 - $src) & ($src - 0x5b)) >> 8) & ($src - 64);
54
55	// if ($src > 0x60 && $src < 0x7b) $ret += $src - 0x61 + 26 + 1; // -70
56	$ret += (((0x60 - $src) & ($src - 0x7b)) >> 8) & ($src - 70);
57
58	// if ($src > 0x2f && $src < 0x3a) $ret += $src - 0x30 + 52 + 1; // 5
59	$ret += (((0x2f - $src) & ($src - 0x3a)) >> 8) & ($src + 5);
60
61	// if ($src == 0x2c) $ret += 62 + 1;
62	$ret += (((0x2c - $src) & ($src - 0x2e)) >> 8) & 63;
63
64	// if ($src == 0x5f) ret += 63 + 1;
65	$ret += (((0x5e - $src) & ($src - 0x60)) >> 8) & 64;
66
67	return $ret;
68	}
69
70	/**
71	* Uses bitwise operators instead of table-lookups to turn 8-bit integers
72	* into 6-bit integers.
73	*
74	* @param int $src
75	* @return string
76	*/
77	protected static function encode6Bits(int $src): string
78	{
79	$diff = 0x41;
80
81	// if ($src > 25) $diff += 0x61 - 0x41 - 26; // 6
82	$diff += ((25 - $src) >> 8) & 6;
83
84	// if ($src > 51) $diff += 0x30 - 0x61 - 26; // -75
85	$diff -= ((51 - $src) >> 8) & 75;
86
87	// if ($src > 61) $diff += 0x2d - 0x30 - 10; // -13
88	$diff -= ((61 - $src) >> 8) & 13;
89
90	// if ($src > 62) $diff += 0x5f - 0x2b - 1; // 3
91	$diff += ((62 - $src) >> 8) & 49;
92
93	return \pack('C', $src + $diff);
94	}
95	}
96