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1927933f5SAndreas Gohr<?php
2927933f5SAndreas Gohrdeclare(strict_types=1);
3927933f5SAndreas Gohrnamespace ParagonIE\ConstantTime;
4927933f5SAndreas Gohr
5*8e88a29bSAndreas Gohruse Override;
6*8e88a29bSAndreas Gohr
7927933f5SAndreas Gohr/**
8927933f5SAndreas Gohr *  Copyright (c) 2016 - 2022 Paragon Initiative Enterprises.
9927933f5SAndreas Gohr *  Copyright (c) 2014 Steve "Sc00bz" Thomas (steve at tobtu dot com)
10927933f5SAndreas Gohr *
11927933f5SAndreas Gohr *  Permission is hereby granted, free of charge, to any person obtaining a copy
12927933f5SAndreas Gohr *  of this software and associated documentation files (the "Software"), to deal
13927933f5SAndreas Gohr *  in the Software without restriction, including without limitation the rights
14927933f5SAndreas Gohr *  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
15927933f5SAndreas Gohr *  copies of the Software, and to permit persons to whom the Software is
16927933f5SAndreas Gohr *  furnished to do so, subject to the following conditions:
17927933f5SAndreas Gohr *
18927933f5SAndreas Gohr *  The above copyright notice and this permission notice shall be included in all
19927933f5SAndreas Gohr *  copies or substantial portions of the Software.
20927933f5SAndreas Gohr *
21927933f5SAndreas Gohr *  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
22927933f5SAndreas Gohr *  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
23927933f5SAndreas Gohr *  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
24927933f5SAndreas Gohr *  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
25927933f5SAndreas Gohr *  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
26927933f5SAndreas Gohr *  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
27927933f5SAndreas Gohr *  SOFTWARE.
28927933f5SAndreas Gohr */
29927933f5SAndreas Gohr
30927933f5SAndreas Gohr/**
31927933f5SAndreas Gohr * Class Base64DotSlashOrdered
32927933f5SAndreas Gohr * ./[0-9][A-Z][a-z]
33927933f5SAndreas Gohr *
34927933f5SAndreas Gohr * @package ParagonIE\ConstantTime
35927933f5SAndreas Gohr */
36927933f5SAndreas Gohrabstract class Base64DotSlashOrdered extends Base64
37927933f5SAndreas Gohr{
38927933f5SAndreas Gohr    /**
39927933f5SAndreas Gohr     * Uses bitwise operators instead of table-lookups to turn 6-bit integers
40927933f5SAndreas Gohr     * into 8-bit integers.
41927933f5SAndreas Gohr     *
42927933f5SAndreas Gohr     * Base64 character set:
43927933f5SAndreas Gohr     * [.-9]      [A-Z]      [a-z]
44927933f5SAndreas Gohr     * 0x2e-0x39, 0x41-0x5a, 0x61-0x7a
45927933f5SAndreas Gohr     *
46927933f5SAndreas Gohr     * @param int $src
47927933f5SAndreas Gohr     * @return int
48927933f5SAndreas Gohr     */
49*8e88a29bSAndreas Gohr    #[Override]
50927933f5SAndreas Gohr    protected static function decode6Bits(int $src): int
51927933f5SAndreas Gohr    {
52927933f5SAndreas Gohr        $ret = -1;
53927933f5SAndreas Gohr
54927933f5SAndreas Gohr        // if ($src > 0x2d && $src < 0x3a) ret += $src - 0x2e + 1; // -45
55927933f5SAndreas Gohr        $ret += (((0x2d - $src) & ($src - 0x3a)) >> 8) & ($src - 45);
56927933f5SAndreas Gohr
57927933f5SAndreas Gohr        // if ($src > 0x40 && $src < 0x5b) ret += $src - 0x41 + 12 + 1; // -52
58927933f5SAndreas Gohr        $ret += (((0x40 - $src) & ($src - 0x5b)) >> 8) & ($src - 52);
59927933f5SAndreas Gohr
60927933f5SAndreas Gohr        // if ($src > 0x60 && $src < 0x7b) ret += $src - 0x61 + 38 + 1; // -58
61927933f5SAndreas Gohr        $ret += (((0x60 - $src) & ($src - 0x7b)) >> 8) & ($src - 58);
62927933f5SAndreas Gohr
63927933f5SAndreas Gohr        return $ret;
64927933f5SAndreas Gohr    }
65927933f5SAndreas Gohr
66927933f5SAndreas Gohr    /**
67927933f5SAndreas Gohr     * Uses bitwise operators instead of table-lookups to turn 8-bit integers
68927933f5SAndreas Gohr     * into 6-bit integers.
69927933f5SAndreas Gohr     *
70927933f5SAndreas Gohr     * @param int $src
71927933f5SAndreas Gohr     * @return string
72927933f5SAndreas Gohr     */
73*8e88a29bSAndreas Gohr    #[Override]
74927933f5SAndreas Gohr    protected static function encode6Bits(int $src): string
75927933f5SAndreas Gohr    {
76927933f5SAndreas Gohr        $src += 0x2e;
77927933f5SAndreas Gohr
78927933f5SAndreas Gohr        // if ($src > 0x39) $src += 0x41 - 0x3a; // 7
79927933f5SAndreas Gohr        $src += ((0x39 - $src) >> 8) & 7;
80927933f5SAndreas Gohr
81927933f5SAndreas Gohr        // if ($src > 0x5a) $src += 0x61 - 0x5b; // 6
82927933f5SAndreas Gohr        $src += ((0x5a - $src) >> 8) & 6;
83927933f5SAndreas Gohr
84927933f5SAndreas Gohr        return \pack('C', $src);
85927933f5SAndreas Gohr    }
86927933f5SAndreas Gohr}
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