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Long Term Support Release

  • Bug fixes for general core bugs in 3.9.x will end* 10 May 2021 (12 months).
  • Bug fixes for security issues in 3.9.x will end* 8 May 2023 (36 months).
  • PHP version: minimum PHP 7.2.0 Note: minimum PHP version has increased since Moodle 3.8. PHP 7.3.x and 7.4.x are supported too.

Differences Between: [Versions 39 and 311] [Versions 39 and 400] [Versions 39 and 401] [Versions 39 and 402] [Versions 39 and 403]

   1  <?php
   2  /**
   3   * SimplePie
   4   *
   5   * A PHP-Based RSS and Atom Feed Framework.
   6   * Takes the hard work out of managing a complete RSS/Atom solution.
   7   *
   8   * Copyright (c) 2004-2016, Ryan Parman, Geoffrey Sneddon, Ryan McCue, and contributors
   9   * All rights reserved.
  10   *
  11   * Redistribution and use in source and binary forms, with or without modification, are
  12   * permitted provided that the following conditions are met:
  13   *
  14   * 	 * Redistributions of source code must retain the above copyright notice, this list of
  15   * 	   conditions and the following disclaimer.
  16   *
  17   * 	 * Redistributions in binary form must reproduce the above copyright notice, this list
  18   * 	   of conditions and the following disclaimer in the documentation and/or other materials
  19   * 	   provided with the distribution.
  20   *
  21   * 	 * Neither the name of the SimplePie Team nor the names of its contributors may be used
  22   * 	   to endorse or promote products derived from this software without specific prior
  23   * 	   written permission.
  24   *
  25   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS
  26   * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
  27   * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS
  28   * AND CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  29   * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
  30   * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  31   * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
  32   * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  33   * POSSIBILITY OF SUCH DAMAGE.
  34   *
  35   * @package SimplePie
  36   * @copyright 2004-2016 Ryan Parman, Geoffrey Sneddon, Ryan McCue
  37   * @author Ryan Parman
  38   * @author Geoffrey Sneddon
  39   * @author Ryan McCue
  40   * @link http://simplepie.org/ SimplePie
  41   * @license http://www.opensource.org/licenses/bsd-license.php BSD License
  42   */
  43  
  44  
  45  /**
  46   * HTTP Response Parser
  47   *
  48   * @package SimplePie
  49   * @subpackage HTTP
  50   */
  51  class SimplePie_HTTP_Parser
  52  {
  53  	 /**
  54  	  * HTTP Version
  55  	  *
  56  	  * @var float
  57  	  */
  58  	 public $http_version = 0.0;
  59  
  60  	 /**
  61  	  * Status code
  62  	  *
  63  	  * @var int
  64  	  */
  65  	 public $status_code = 0;
  66  
  67  	 /**
  68  	  * Reason phrase
  69  	  *
  70  	  * @var string
  71  	  */
  72  	 public $reason = '';
  73  
  74  	 /**
  75  	  * Key/value pairs of the headers
  76  	  *
  77  	  * @var array
  78  	  */
  79  	 public $headers = array();
  80  
  81  	 /**
  82  	  * Body of the response
  83  	  *
  84  	  * @var string
  85  	  */
  86  	 public $body = '';
  87  
  88  	 /**
  89  	  * Current state of the state machine
  90  	  *
  91  	  * @var string
  92  	  */
  93  	 protected $state = 'http_version';
  94  
  95  	 /**
  96  	  * Input data
  97  	  *
  98  	  * @var string
  99  	  */
 100  	 protected $data = '';
 101  
 102  	 /**
 103  	  * Input data length (to avoid calling strlen() everytime this is needed)
 104  	  *
 105  	  * @var int
 106  	  */
 107  	 protected $data_length = 0;
 108  
 109  	 /**
 110  	  * Current position of the pointer
 111  	  *
 112  	  * @var int
 113  	  */
 114  	 protected $position = 0;
 115  
 116  	 /**
 117  	  * Name of the hedaer currently being parsed
 118  	  *
 119  	  * @var string
 120  	  */
 121  	 protected $name = '';
 122  
 123  	 /**
 124  	  * Value of the hedaer currently being parsed
 125  	  *
 126  	  * @var string
 127  	  */
 128  	 protected $value = '';
 129  
 130  	 /**
 131  	  * Create an instance of the class with the input data
 132  	  *
 133  	  * @param string $data Input data
 134  	  */
 135  	public function __construct($data)
 136  	 {
 137  	 	 $this->data = $data;
 138  	 	 $this->data_length = strlen($this->data);
 139  	 }
 140  
 141  	 /**
 142  	  * Parse the input data
 143  	  *
 144  	  * @return bool true on success, false on failure
 145  	  */
 146  	public function parse()
 147  	 {
 148  	 	 while ($this->state && $this->state !== 'emit' && $this->has_data())
 149  	 	 {
 150  	 	 	 $state = $this->state;
 151  	 	 	 $this->$state();
 152  	 	 }
 153  	 	 $this->data = '';
 154  	 	 if ($this->state === 'emit' || $this->state === 'body')
 155  	 	 {
 156  	 	 	 return true;
 157  	 	 }
 158  
 159  	 	 $this->http_version = '';
 160  	 	 $this->status_code = '';
 161  	 	 $this->reason = '';
 162  	 	 $this->headers = array();
 163  	 	 $this->body = '';
 164  	 	 return false;
 165  	 }
 166  
 167  	 /**
 168  	  * Check whether there is data beyond the pointer
 169  	  *
 170  	  * @return bool true if there is further data, false if not
 171  	  */
 172  	protected function has_data()
 173  	 {
 174  	 	 return (bool) ($this->position < $this->data_length);
 175  	 }
 176  
 177  	 /**
 178  	  * See if the next character is LWS
 179  	  *
 180  	  * @return bool true if the next character is LWS, false if not
 181  	  */
 182  	protected function is_linear_whitespace()
 183  	 {
 184  	 	 return (bool) ($this->data[$this->position] === "\x09"
 185  	 	 	 || $this->data[$this->position] === "\x20"
 186  	 	 	 || ($this->data[$this->position] === "\x0A"
 187  	 	 	 	 && isset($this->data[$this->position + 1])
 188  	 	 	 	 && ($this->data[$this->position + 1] === "\x09" || $this->data[$this->position + 1] === "\x20")));
 189  	 }
 190  
 191  	 /**
 192  	  * Parse the HTTP version
 193  	  */
 194  	protected function http_version()
 195  	 {
 196  	 	 if (strpos($this->data, "\x0A") !== false && strtoupper(substr($this->data, 0, 5)) === 'HTTP/')
 197  	 	 {
 198  	 	 	 $len = strspn($this->data, '0123456789.', 5);
 199  	 	 	 $this->http_version = substr($this->data, 5, $len);
 200  	 	 	 $this->position += 5 + $len;
 201  	 	 	 if (substr_count($this->http_version, '.') <= 1)
 202  	 	 	 {
 203  	 	 	 	 $this->http_version = (float) $this->http_version;
 204  	 	 	 	 $this->position += strspn($this->data, "\x09\x20", $this->position);
 205  	 	 	 	 $this->state = 'status';
 206  	 	 	 }
 207  	 	 	 else
 208  	 	 	 {
 209  	 	 	 	 $this->state = false;
 210  	 	 	 }
 211  	 	 }
 212  	 	 else
 213  	 	 {
 214  	 	 	 $this->state = false;
 215  	 	 }
 216  	 }
 217  
 218  	 /**
 219  	  * Parse the status code
 220  	  */
 221  	protected function status()
 222  	 {
 223  	 	 if ($len = strspn($this->data, '0123456789', $this->position))
 224  	 	 {
 225  	 	 	 $this->status_code = (int) substr($this->data, $this->position, $len);
 226  	 	 	 $this->position += $len;
 227  	 	 	 $this->state = 'reason';
 228  	 	 }
 229  	 	 else
 230  	 	 {
 231  	 	 	 $this->state = false;
 232  	 	 }
 233  	 }
 234  
 235  	 /**
 236  	  * Parse the reason phrase
 237  	  */
 238  	protected function reason()
 239  	 {
 240  	 	 $len = strcspn($this->data, "\x0A", $this->position);
 241  	 	 $this->reason = trim(substr($this->data, $this->position, $len), "\x09\x0D\x20");
 242  	 	 $this->position += $len + 1;
 243  	 	 $this->state = 'new_line';
 244  	 }
 245  
 246  	 /**
 247  	  * Deal with a new line, shifting data around as needed
 248  	  */
 249  	protected function new_line()
 250  	 {
 251  	 	 $this->value = trim($this->value, "\x0D\x20");
 252  	 	 if ($this->name !== '' && $this->value !== '')
 253  	 	 {
 254  	 	 	 $this->name = strtolower($this->name);
 255  	 	 	 // We should only use the last Content-Type header. c.f. issue #1
 256  	 	 	 if (isset($this->headers[$this->name]) && $this->name !== 'content-type')
 257  	 	 	 {
 258  	 	 	 	 $this->headers[$this->name] .= ', ' . $this->value;
 259  	 	 	 }
 260  	 	 	 else
 261  	 	 	 {
 262  	 	 	 	 $this->headers[$this->name] = $this->value;
 263  	 	 	 }
 264  	 	 }
 265  	 	 $this->name = '';
 266  	 	 $this->value = '';
 267  	 	 if (substr($this->data[$this->position], 0, 2) === "\x0D\x0A")
 268  	 	 {
 269  	 	 	 $this->position += 2;
 270  	 	 	 $this->state = 'body';
 271  	 	 }
 272  	 	 elseif ($this->data[$this->position] === "\x0A")
 273  	 	 {
 274  	 	 	 $this->position++;
 275  	 	 	 $this->state = 'body';
 276  	 	 }
 277  	 	 else
 278  	 	 {
 279  	 	 	 $this->state = 'name';
 280  	 	 }
 281  	 }
 282  
 283  	 /**
 284  	  * Parse a header name
 285  	  */
 286  	protected function name()
 287  	 {
 288  	 	 $len = strcspn($this->data, "\x0A:", $this->position);
 289  	 	 if (isset($this->data[$this->position + $len]))
 290  	 	 {
 291  	 	 	 if ($this->data[$this->position + $len] === "\x0A")
 292  	 	 	 {
 293  	 	 	 	 $this->position += $len;
 294  	 	 	 	 $this->state = 'new_line';
 295  	 	 	 }
 296  	 	 	 else
 297  	 	 	 {
 298  	 	 	 	 $this->name = substr($this->data, $this->position, $len);
 299  	 	 	 	 $this->position += $len + 1;
 300  	 	 	 	 $this->state = 'value';
 301  	 	 	 }
 302  	 	 }
 303  	 	 else
 304  	 	 {
 305  	 	 	 $this->state = false;
 306  	 	 }
 307  	 }
 308  
 309  	 /**
 310  	  * Parse LWS, replacing consecutive LWS characters with a single space
 311  	  */
 312  	protected function linear_whitespace()
 313  	 {
 314  	 	 do
 315  	 	 {
 316  	 	 	 if (substr($this->data, $this->position, 2) === "\x0D\x0A")
 317  	 	 	 {
 318  	 	 	 	 $this->position += 2;
 319  	 	 	 }
 320  	 	 	 elseif ($this->data[$this->position] === "\x0A")
 321  	 	 	 {
 322  	 	 	 	 $this->position++;
 323  	 	 	 }
 324  	 	 	 $this->position += strspn($this->data, "\x09\x20", $this->position);
 325  	 	 } while ($this->has_data() && $this->is_linear_whitespace());
 326  	 	 $this->value .= "\x20";
 327  	 }
 328  
 329  	 /**
 330  	  * See what state to move to while within non-quoted header values
 331  	  */
 332  	protected function value()
 333  	 {
 334  	 	 if ($this->is_linear_whitespace())
 335  	 	 {
 336  	 	 	 $this->linear_whitespace();
 337  	 	 }
 338  	 	 else
 339  	 	 {
 340  	 	 	 switch ($this->data[$this->position])
 341  	 	 	 {
 342  	 	 	 	 case '"':
 343  	 	 	 	 	 // Workaround for ETags: we have to include the quotes as
 344  	 	 	 	 	 // part of the tag.
 345  	 	 	 	 	 if (strtolower($this->name) === 'etag')
 346  	 	 	 	 	 {
 347  	 	 	 	 	 	 $this->value .= '"';
 348  	 	 	 	 	 	 $this->position++;
 349  	 	 	 	 	 	 $this->state = 'value_char';
 350  	 	 	 	 	 	 break;
 351  	 	 	 	 	 }
 352  	 	 	 	 	 $this->position++;
 353  	 	 	 	 	 $this->state = 'quote';
 354  	 	 	 	 	 break;
 355  
 356  	 	 	 	 case "\x0A":
 357  	 	 	 	 	 $this->position++;
 358  	 	 	 	 	 $this->state = 'new_line';
 359  	 	 	 	 	 break;
 360  
 361  	 	 	 	 default:
 362  	 	 	 	 	 $this->state = 'value_char';
 363  	 	 	 	 	 break;
 364  	 	 	 }
 365  	 	 }
 366  	 }
 367  
 368  	 /**
 369  	  * Parse a header value while outside quotes
 370  	  */
 371  	protected function value_char()
 372  	 {
 373  	 	 $len = strcspn($this->data, "\x09\x20\x0A\"", $this->position);
 374  	 	 $this->value .= substr($this->data, $this->position, $len);
 375  	 	 $this->position += $len;
 376  	 	 $this->state = 'value';
 377  	 }
 378  
 379  	 /**
 380  	  * See what state to move to while within quoted header values
 381  	  */
 382  	protected function quote()
 383  	 {
 384  	 	 if ($this->is_linear_whitespace())
 385  	 	 {
 386  	 	 	 $this->linear_whitespace();
 387  	 	 }
 388  	 	 else
 389  	 	 {
 390  	 	 	 switch ($this->data[$this->position])
 391  	 	 	 {
 392  	 	 	 	 case '"':
 393  	 	 	 	 	 $this->position++;
 394  	 	 	 	 	 $this->state = 'value';
 395  	 	 	 	 	 break;
 396  
 397  	 	 	 	 case "\x0A":
 398  	 	 	 	 	 $this->position++;
 399  	 	 	 	 	 $this->state = 'new_line';
 400  	 	 	 	 	 break;
 401  
 402  	 	 	 	 case '\\':
 403  	 	 	 	 	 $this->position++;
 404  	 	 	 	 	 $this->state = 'quote_escaped';
 405  	 	 	 	 	 break;
 406  
 407  	 	 	 	 default:
 408  	 	 	 	 	 $this->state = 'quote_char';
 409  	 	 	 	 	 break;
 410  	 	 	 }
 411  	 	 }
 412  	 }
 413  
 414  	 /**
 415  	  * Parse a header value while within quotes
 416  	  */
 417  	protected function quote_char()
 418  	 {
 419  	 	 $len = strcspn($this->data, "\x09\x20\x0A\"\\", $this->position);
 420  	 	 $this->value .= substr($this->data, $this->position, $len);
 421  	 	 $this->position += $len;
 422  	 	 $this->state = 'value';
 423  	 }
 424  
 425  	 /**
 426  	  * Parse an escaped character within quotes
 427  	  */
 428  	protected function quote_escaped()
 429  	 {
 430  	 	 $this->value .= $this->data[$this->position];
 431  	 	 $this->position++;
 432  	 	 $this->state = 'quote';
 433  	 }
 434  
 435  	 /**
 436  	  * Parse the body
 437  	  */
 438  	protected function body()
 439  	 {
 440  	 	 $this->body = substr($this->data, $this->position);
 441  	 	 if (!empty($this->headers['transfer-encoding']))
 442  	 	 {
 443  	 	 	 unset($this->headers['transfer-encoding']);
 444  	 	 	 $this->state = 'chunked';
 445  	 	 }
 446  	 	 else
 447  	 	 {
 448  	 	 	 $this->state = 'emit';
 449  	 	 }
 450  	 }
 451  
 452  	 /**
 453  	  * Parsed a "Transfer-Encoding: chunked" body
 454  	  */
 455  	protected function chunked()
 456  	 {
 457  	 	 if (!preg_match('/^([0-9a-f]+)[^\r\n]*\r\n/i', trim($this->body)))
 458  	 	 {
 459  	 	 	 $this->state = 'emit';
 460  	 	 	 return;
 461  	 	 }
 462  
 463  	 	 $decoded = '';
 464  	 	 $encoded = $this->body;
 465  
 466  	 	 while (true)
 467  	 	 {
 468  	 	 	 $is_chunked = (bool) preg_match( '/^([0-9a-f]+)[^\r\n]*\r\n/i', $encoded, $matches );
 469  	 	 	 if (!$is_chunked)
 470  	 	 	 {
 471  	 	 	 	 // Looks like it's not chunked after all
 472  	 	 	 	 $this->state = 'emit';
 473  	 	 	 	 return;
 474  	 	 	 }
 475  
 476  	 	 	 $length = hexdec(trim($matches[1]));
 477  	 	 	 if ($length === 0)
 478  	 	 	 {
 479  	 	 	 	 // Ignore trailer headers
 480  	 	 	 	 $this->state = 'emit';
 481  	 	 	 	 $this->body = $decoded;
 482  	 	 	 	 return;
 483  	 	 	 }
 484  
 485  	 	 	 $chunk_length = strlen($matches[0]);
 486  	 	 	 $decoded .= $part = substr($encoded, $chunk_length, $length);
 487  	 	 	 $encoded = substr($encoded, $chunk_length + $length + 2);
 488  
 489  	 	 	 if (trim($encoded) === '0' || empty($encoded))
 490  	 	 	 {
 491  	 	 	 	 $this->state = 'emit';
 492  	 	 	 	 $this->body = $decoded;
 493  	 	 	 	 return;
 494  	 	 	 }
 495  	 	 }
 496  	 }
 497  
 498  	 /**
 499  	  * Prepare headers (take care of proxies headers)
 500  	  *
 501  	  * @param string  $headers Raw headers
 502  	  * @param integer $count   Redirection count. Default to 1.
 503  	  *
 504  	  * @return string
 505  	  */
 506  	static public function prepareHeaders($headers, $count = 1)
 507  	 {
 508  	 	 $data = explode("\r\n\r\n", $headers, $count);
 509  	 	 $data = array_pop($data);
 510  	 	 if (false !== stripos($data, "HTTP/1.0 200 Connection established\r\n\r\n")) {
 511  	 	 	 $data = str_ireplace("HTTP/1.0 200 Connection established\r\n\r\n", '', $data);
 512  	 	 }
 513  	 	 if (false !== stripos($data, "HTTP/1.1 200 Connection established\r\n\r\n")) {
 514  	 	 	 $data = str_ireplace("HTTP/1.1 200 Connection established\r\n\r\n", '', $data);
 515  	 	 }
 516  	 	 return $data;
 517  	 }
 518  }