1<?php
2
3/*
4 * This file is part of SwiftMailer.
5 * (c) 2004-2009 Chris Corbyn
6 *
7 * For the full copyright and license information, please view the LICENSE
8 * file that was distributed with this source code.
9 */
10
11/**
12 * Handles Quoted Printable (QP) Encoding in Swift Mailer.
13 *
14 * Possibly the most accurate RFC 2045 QP implementation found in PHP.
15 *
16 * @author     Chris Corbyn
17 */
18class Swift_Encoder_QpEncoder implements Swift_Encoder
19{
20    /**
21     * The CharacterStream used for reading characters (as opposed to bytes).
22     *
23     * @var Swift_CharacterStream
24     */
25    protected $charStream;
26
27    /**
28     * A filter used if input should be canonicalized.
29     *
30     * @var Swift_StreamFilter
31     */
32    protected $filter;
33
34    /**
35     * Pre-computed QP for HUGE optimization.
36     *
37     * @var string[]
38     */
39    protected static $qpMap = [
40        0 => '=00', 1 => '=01', 2 => '=02', 3 => '=03', 4 => '=04',
41        5 => '=05', 6 => '=06', 7 => '=07', 8 => '=08', 9 => '=09',
42        10 => '=0A', 11 => '=0B', 12 => '=0C', 13 => '=0D', 14 => '=0E',
43        15 => '=0F', 16 => '=10', 17 => '=11', 18 => '=12', 19 => '=13',
44        20 => '=14', 21 => '=15', 22 => '=16', 23 => '=17', 24 => '=18',
45        25 => '=19', 26 => '=1A', 27 => '=1B', 28 => '=1C', 29 => '=1D',
46        30 => '=1E', 31 => '=1F', 32 => '=20', 33 => '=21', 34 => '=22',
47        35 => '=23', 36 => '=24', 37 => '=25', 38 => '=26', 39 => '=27',
48        40 => '=28', 41 => '=29', 42 => '=2A', 43 => '=2B', 44 => '=2C',
49        45 => '=2D', 46 => '=2E', 47 => '=2F', 48 => '=30', 49 => '=31',
50        50 => '=32', 51 => '=33', 52 => '=34', 53 => '=35', 54 => '=36',
51        55 => '=37', 56 => '=38', 57 => '=39', 58 => '=3A', 59 => '=3B',
52        60 => '=3C', 61 => '=3D', 62 => '=3E', 63 => '=3F', 64 => '=40',
53        65 => '=41', 66 => '=42', 67 => '=43', 68 => '=44', 69 => '=45',
54        70 => '=46', 71 => '=47', 72 => '=48', 73 => '=49', 74 => '=4A',
55        75 => '=4B', 76 => '=4C', 77 => '=4D', 78 => '=4E', 79 => '=4F',
56        80 => '=50', 81 => '=51', 82 => '=52', 83 => '=53', 84 => '=54',
57        85 => '=55', 86 => '=56', 87 => '=57', 88 => '=58', 89 => '=59',
58        90 => '=5A', 91 => '=5B', 92 => '=5C', 93 => '=5D', 94 => '=5E',
59        95 => '=5F', 96 => '=60', 97 => '=61', 98 => '=62', 99 => '=63',
60        100 => '=64', 101 => '=65', 102 => '=66', 103 => '=67', 104 => '=68',
61        105 => '=69', 106 => '=6A', 107 => '=6B', 108 => '=6C', 109 => '=6D',
62        110 => '=6E', 111 => '=6F', 112 => '=70', 113 => '=71', 114 => '=72',
63        115 => '=73', 116 => '=74', 117 => '=75', 118 => '=76', 119 => '=77',
64        120 => '=78', 121 => '=79', 122 => '=7A', 123 => '=7B', 124 => '=7C',
65        125 => '=7D', 126 => '=7E', 127 => '=7F', 128 => '=80', 129 => '=81',
66        130 => '=82', 131 => '=83', 132 => '=84', 133 => '=85', 134 => '=86',
67        135 => '=87', 136 => '=88', 137 => '=89', 138 => '=8A', 139 => '=8B',
68        140 => '=8C', 141 => '=8D', 142 => '=8E', 143 => '=8F', 144 => '=90',
69        145 => '=91', 146 => '=92', 147 => '=93', 148 => '=94', 149 => '=95',
70        150 => '=96', 151 => '=97', 152 => '=98', 153 => '=99', 154 => '=9A',
71        155 => '=9B', 156 => '=9C', 157 => '=9D', 158 => '=9E', 159 => '=9F',
72        160 => '=A0', 161 => '=A1', 162 => '=A2', 163 => '=A3', 164 => '=A4',
73        165 => '=A5', 166 => '=A6', 167 => '=A7', 168 => '=A8', 169 => '=A9',
74        170 => '=AA', 171 => '=AB', 172 => '=AC', 173 => '=AD', 174 => '=AE',
75        175 => '=AF', 176 => '=B0', 177 => '=B1', 178 => '=B2', 179 => '=B3',
76        180 => '=B4', 181 => '=B5', 182 => '=B6', 183 => '=B7', 184 => '=B8',
77        185 => '=B9', 186 => '=BA', 187 => '=BB', 188 => '=BC', 189 => '=BD',
78        190 => '=BE', 191 => '=BF', 192 => '=C0', 193 => '=C1', 194 => '=C2',
79        195 => '=C3', 196 => '=C4', 197 => '=C5', 198 => '=C6', 199 => '=C7',
80        200 => '=C8', 201 => '=C9', 202 => '=CA', 203 => '=CB', 204 => '=CC',
81        205 => '=CD', 206 => '=CE', 207 => '=CF', 208 => '=D0', 209 => '=D1',
82        210 => '=D2', 211 => '=D3', 212 => '=D4', 213 => '=D5', 214 => '=D6',
83        215 => '=D7', 216 => '=D8', 217 => '=D9', 218 => '=DA', 219 => '=DB',
84        220 => '=DC', 221 => '=DD', 222 => '=DE', 223 => '=DF', 224 => '=E0',
85        225 => '=E1', 226 => '=E2', 227 => '=E3', 228 => '=E4', 229 => '=E5',
86        230 => '=E6', 231 => '=E7', 232 => '=E8', 233 => '=E9', 234 => '=EA',
87        235 => '=EB', 236 => '=EC', 237 => '=ED', 238 => '=EE', 239 => '=EF',
88        240 => '=F0', 241 => '=F1', 242 => '=F2', 243 => '=F3', 244 => '=F4',
89        245 => '=F5', 246 => '=F6', 247 => '=F7', 248 => '=F8', 249 => '=F9',
90        250 => '=FA', 251 => '=FB', 252 => '=FC', 253 => '=FD', 254 => '=FE',
91        255 => '=FF',
92        ];
93
94    protected static $safeMapShare = [];
95
96    /**
97     * A map of non-encoded ascii characters.
98     *
99     * @var string[]
100     */
101    protected $safeMap = [];
102
103    /**
104     * Creates a new QpEncoder for the given CharacterStream.
105     *
106     * @param Swift_CharacterStream $charStream to use for reading characters
107     * @param Swift_StreamFilter    $filter     if input should be canonicalized
108     */
109    public function __construct(Swift_CharacterStream $charStream, Swift_StreamFilter $filter = null)
110    {
111        $this->charStream = $charStream;
112        if (!isset(self::$safeMapShare[$this->getSafeMapShareId()])) {
113            $this->initSafeMap();
114            self::$safeMapShare[$this->getSafeMapShareId()] = $this->safeMap;
115        } else {
116            $this->safeMap = self::$safeMapShare[$this->getSafeMapShareId()];
117        }
118        $this->filter = $filter;
119    }
120
121    public function __sleep()
122    {
123        return ['charStream', 'filter'];
124    }
125
126    public function __wakeup()
127    {
128        if (!isset(self::$safeMapShare[$this->getSafeMapShareId()])) {
129            $this->initSafeMap();
130            self::$safeMapShare[$this->getSafeMapShareId()] = $this->safeMap;
131        } else {
132            $this->safeMap = self::$safeMapShare[$this->getSafeMapShareId()];
133        }
134    }
135
136    protected function getSafeMapShareId()
137    {
138        return static::class;
139    }
140
141    protected function initSafeMap()
142    {
143        foreach (array_merge(
144            [0x09, 0x20], range(0x21, 0x3C), range(0x3E, 0x7E)) as $byte) {
145            $this->safeMap[$byte] = \chr($byte);
146        }
147    }
148
149    /**
150     * Takes an unencoded string and produces a QP encoded string from it.
151     *
152     * QP encoded strings have a maximum line length of 76 characters.
153     * If the first line needs to be shorter, indicate the difference with
154     * $firstLineOffset.
155     *
156     * @param string $string          to encode
157     * @param int    $firstLineOffset optional
158     * @param int    $maxLineLength   optional 0 indicates the default of 76 chars
159     *
160     * @return string
161     */
162    public function encodeString($string, $firstLineOffset = 0, $maxLineLength = 0)
163    {
164        if ($maxLineLength > 76 || $maxLineLength <= 0) {
165            $maxLineLength = 76;
166        }
167
168        $thisLineLength = $maxLineLength - $firstLineOffset;
169
170        $lines = [];
171        $lNo = 0;
172        $lines[$lNo] = '';
173        $currentLine = &$lines[$lNo++];
174        $size = $lineLen = 0;
175
176        $this->charStream->flushContents();
177        $this->charStream->importString($string);
178
179        // Fetching more than 4 chars at one is slower, as is fetching fewer bytes
180        // Conveniently 4 chars is the UTF-8 safe number since UTF-8 has up to 6
181        // bytes per char and (6 * 4 * 3 = 72 chars per line) * =NN is 3 bytes
182        while (false !== $bytes = $this->nextSequence()) {
183            // If we're filtering the input
184            if (isset($this->filter)) {
185                // If we can't filter because we need more bytes
186                while ($this->filter->shouldBuffer($bytes)) {
187                    // Then collect bytes into the buffer
188                    if (false === $moreBytes = $this->nextSequence(1)) {
189                        break;
190                    }
191
192                    foreach ($moreBytes as $b) {
193                        $bytes[] = $b;
194                    }
195                }
196                // And filter them
197                $bytes = $this->filter->filter($bytes);
198            }
199
200            $enc = $this->encodeByteSequence($bytes, $size);
201
202            $i = strpos($enc, '=0D=0A');
203            $newLineLength = $lineLen + (false === $i ? $size : $i);
204
205            if ($currentLine && $newLineLength >= $thisLineLength) {
206                $lines[$lNo] = '';
207                $currentLine = &$lines[$lNo++];
208                $thisLineLength = $maxLineLength;
209                $lineLen = 0;
210            }
211
212            $currentLine .= $enc;
213
214            if (false === $i) {
215                $lineLen += $size;
216            } else {
217                // 6 is the length of '=0D=0A'.
218                $lineLen = $size - strrpos($enc, '=0D=0A') - 6;
219            }
220        }
221
222        return $this->standardize(implode("=\r\n", $lines));
223    }
224
225    /**
226     * Updates the charset used.
227     *
228     * @param string $charset
229     */
230    public function charsetChanged($charset)
231    {
232        $this->charStream->setCharacterSet($charset);
233    }
234
235    /**
236     * Encode the given byte array into a verbatim QP form.
237     *
238     * @param int[] $bytes
239     * @param int   $size
240     *
241     * @return string
242     */
243    protected function encodeByteSequence(array $bytes, &$size)
244    {
245        $ret = '';
246        $size = 0;
247        foreach ($bytes as $b) {
248            if (isset($this->safeMap[$b])) {
249                $ret .= $this->safeMap[$b];
250                ++$size;
251            } else {
252                $ret .= self::$qpMap[$b];
253                $size += 3;
254            }
255        }
256
257        return $ret;
258    }
259
260    /**
261     * Get the next sequence of bytes to read from the char stream.
262     *
263     * @param int $size number of bytes to read
264     *
265     * @return int[]
266     */
267    protected function nextSequence($size = 4)
268    {
269        return $this->charStream->readBytes($size);
270    }
271
272    /**
273     * Make sure CRLF is correct and HT/SPACE are in valid places.
274     *
275     * @param string $string
276     *
277     * @return string
278     */
279    protected function standardize($string)
280    {
281        $string = str_replace(["\t=0D=0A", ' =0D=0A', '=0D=0A'],
282            ["=09\r\n", "=20\r\n", "\r\n"], $string
283            );
284        switch ($end = \ord(substr($string, -1))) {
285            case 0x09:
286            case 0x20:
287                $string = substr_replace($string, self::$qpMap[$end], -1);
288        }
289
290        return $string;
291    }
292
293    /**
294     * Make a deep copy of object.
295     */
296    public function __clone()
297    {
298        $this->charStream = clone $this->charStream;
299    }
300}
301