src/applications/config/check/PhabricatorWebServerSetupCheck.php

   1 <?php
   2
   3 final class PhabricatorWebServerSetupCheck extends PhabricatorSetupCheck {
   4
   5   public function getDefaultGroup() {
   6     return self::GROUP_OTHER;
   7   }
   8
   9   protected function executeChecks() {
  10     // The documentation says these headers exist, but it's not clear if they
  11     // are entirely reliable in practice.
  12     if (isset($_SERVER['HTTP_X_MOD_PAGESPEED']) ||
  13         isset($_SERVER['HTTP_X_PAGE_SPEED'])) {
  14       $this->newIssue('webserver.pagespeed')
  15         ->setName(pht('Disable Pagespeed'))
  16         ->setSummary(pht('Pagespeed is enabled, but should be disabled.'))
  17         ->setMessage(
  18           pht(
  19             'Phabricator received an "X-Mod-Pagespeed" or "X-Page-Speed" '.
  20             'HTTP header on this request, which indicates that you have '.
  21             'enabled "mod_pagespeed" on this server. This module is not '.
  22             'compatible with Phabricator. You should disable it.'));
  23     }
  24
  25     $base_uri = PhabricatorEnv::getEnvConfig('phabricator.base-uri');
  26     if (!strlen($base_uri)) {
  27       // If `phabricator.base-uri` is not set then we can't really do
  28       // anything.
  29       return;
  30     }
  31
  32     $expect_user = 'alincoln';
  33     $expect_pass = 'hunter2';
  34
  35     $send_path = '/test-%252A/';
  36     $expect_path = '/test-%2A/';
  37
  38     $expect_key = 'duck-sound';
  39     $expect_value = 'quack';
  40
  41     $base_uri = id(new PhutilURI($base_uri))
  42       ->setPath($send_path)
  43       ->replaceQueryParam($expect_key, $expect_value);
  44
  45     $self_future = id(new HTTPSFuture($base_uri))
  46       ->addHeader('X-Phabricator-SelfCheck', 1)
  47       ->addHeader('Accept-Encoding', 'gzip')
  48       ->setDisableContentDecoding(true)
  49       ->setHTTPBasicAuthCredentials(
  50         $expect_user,
  51         new PhutilOpaqueEnvelope($expect_pass))
  52       ->setTimeout(5);
  53
  54     if (AphrontRequestStream::supportsGzip()) {
  55       $gzip_uncompressed = str_repeat('Quack! ', 128);
  56       $gzip_compressed = gzencode($gzip_uncompressed);
  57
  58       $gzip_future = id(new HTTPSFuture($base_uri))
  59         ->addHeader('X-Phabricator-SelfCheck', 1)
  60         ->addHeader('Content-Encoding', 'gzip')
  61         ->setTimeout(5)
  62         ->setData($gzip_compressed);
  63
  64     } else {
  65       $gzip_future = null;
  66     }
  67
  68     // Make a request to the metadata service available on EC2 instances,
  69     // to test if we're running on a T2 instance in AWS so we can warn that
  70     // this is a bad idea. Outside of AWS, this request will just fail.
  71     $ec2_uri = 'http://169.254.169.254/latest/meta-data/instance-type';
  72     $ec2_future = id(new HTTPSFuture($ec2_uri))
  73       ->setTimeout(1);
  74
  75     $futures = array(
  76       $self_future,
  77       $ec2_future,
  78     );
  79
  80     if ($gzip_future) {
  81       $futures[] = $gzip_future;
  82     }
  83
  84     $futures = new FutureIterator($futures);
  85     foreach ($futures as $future) {
  86       // Just resolve the futures here.
  87     }
  88
  89     try {
  90       list($body) = $ec2_future->resolvex();
  91       $body = trim($body);
  92       if (preg_match('/^t2/', $body)) {
  93         $message = pht(
  94           'Phabricator appears to be installed on a very small EC2 instance '.
  95           '(of class "%s") with burstable CPU. This is strongly discouraged. '.
  96           'Phabricator regularly needs CPU, and these instances are often '.
  97           'choked to death by CPU throttling. Use an instance with a normal '.
  98           'CPU instead.',
  99           $body);
 100
 101         $this->newIssue('ec2.burstable')
 102           ->setName(pht('Installed on Burstable CPU Instance'))
 103           ->setSummary(
 104             pht(
 105               'Do not install Phabricator on an instance class with '.
 106               'burstable CPU.'))
 107           ->setMessage($message);
 108       }
 109     } catch (Exception $ex) {
 110       // If this fails, just continue. We're probably not running in EC2.
 111     }
 112
 113     try {
 114       list($body, $headers) = $self_future->resolvex();
 115     } catch (Exception $ex) {
 116       // If this fails for whatever reason, just ignore it. Hopefully, the
 117       // error is obvious and the user can correct it on their own, but we
 118       // can't do much to offer diagnostic advice.
 119       return;
 120     }
 121
 122     if (BaseHTTPFuture::getHeader($headers, 'Content-Encoding') != 'gzip') {
 123       $message = pht(
 124         'Phabricator sent itself a request with "Accept-Encoding: gzip", '.
 125         'but received an uncompressed response.'.
 126         "\n\n".
 127         'This may indicate that your webserver is not configured to '.
 128         'compress responses. If so, you should enable compression. '.
 129         'Compression can dramatically improve performance, especially '.
 130         'for clients with less bandwidth.');
 131
 132       $this->newIssue('webserver.gzip')
 133         ->setName(pht('GZip Compression May Not Be Enabled'))
 134         ->setSummary(pht('Your webserver may have compression disabled.'))
 135         ->setMessage($message);
 136     } else {
 137       if (function_exists('gzdecode')) {
 138         $body = @gzdecode($body);
 139       } else {
 140         $body = null;
 141       }
 142       if (!$body) {
 143         // For now, just bail if we can't decode the response.
 144         // This might need to use the stronger magic in "AphrontRequestStream"
 145         // to decode more reliably.
 146         return;
 147       }
 148     }
 149
 150     $structure = null;
 151     $extra_whitespace = ($body !== trim($body));
 152
 153     try {
 154       $structure = phutil_json_decode(trim($body));
 155     } catch (Exception $ex) {
 156       // Ignore the exception, we only care if the decode worked or not.
 157     }
 158
 159     if (!$structure || $extra_whitespace) {
 160       if (!$structure) {
 161         $short = id(new PhutilUTF8StringTruncator())
 162           ->setMaximumGlyphs(1024)
 163           ->truncateString($body);
 164
 165         $message = pht(
 166           'Phabricator sent itself a test request with the '.
 167           '"X-Phabricator-SelfCheck" header and expected to get a valid JSON '.
 168           'response back. Instead, the response begins:'.
 169           "\n\n".
 170           '%s'.
 171           "\n\n".
 172           'Something is misconfigured or otherwise mangling responses.',
 173           phutil_tag('pre', array(), $short));
 174       } else {
 175         $message = pht(
 176           'Phabricator sent itself a test request and expected to get a bare '.
 177           'JSON response back. It received a JSON response, but the response '.
 178           'had extra whitespace at the beginning or end.'.
 179           "\n\n".
 180           'This usually means you have edited a file and left whitespace '.
 181           'characters before the opening %s tag, or after a closing %s tag. '.
 182           'Remove any leading whitespace, and prefer to omit closing tags.',
 183           phutil_tag('tt', array(), '<?php'),
 184           phutil_tag('tt', array(), '?>'));
 185       }
 186
 187       $this->newIssue('webserver.mangle')
 188         ->setName(pht('Mangled Webserver Response'))
 189         ->setSummary(pht('Your webserver produced an unexpected response.'))
 190         ->setMessage($message);
 191
 192       // We can't run the other checks if we could not decode the response.
 193       if (!$structure) {
 194         return;
 195       }
 196     }
 197
 198     $actual_user = idx($structure, 'user');
 199     $actual_pass = idx($structure, 'pass');
 200     if (($expect_user != $actual_user) || ($actual_pass != $expect_pass)) {
 201       $message = pht(
 202         'Phabricator sent itself a test request with an "Authorization" HTTP '.
 203         'header, and expected those credentials to be transmitted. However, '.
 204         'they were absent or incorrect when received. Phabricator sent '.
 205         'username "%s" with password "%s"; received username "%s" and '.
 206         'password "%s".'.
 207         "\n\n".
 208         'Your webserver may not be configured to forward HTTP basic '.
 209         'authentication. If you plan to use basic authentication (for '.
 210         'example, to access repositories) you should reconfigure it.',
 211         $expect_user,
 212         $expect_pass,
 213         $actual_user,
 214         $actual_pass);
 215
 216       $this->newIssue('webserver.basic-auth')
 217         ->setName(pht('HTTP Basic Auth Not Configured'))
 218         ->setSummary(pht('Your webserver is not forwarding credentials.'))
 219         ->setMessage($message);
 220     }
 221
 222     $actual_path = idx($structure, 'path');
 223     if ($expect_path != $actual_path) {
 224       $message = pht(
 225         'Phabricator sent itself a test request with an unusual path, to '.
 226         'test if your webserver is rewriting paths correctly. The path was '.
 227         'not transmitted correctly.'.
 228         "\n\n".
 229         'Phabricator sent a request to path "%s", and expected the webserver '.
 230         'to decode and rewrite that path so that it received a request for '.
 231         '"%s". However, it received a request for "%s" instead.'.
 232         "\n\n".
 233         'Verify that your rewrite rules are configured correctly, following '.
 234         'the instructions in the documentation. If path encoding is not '.
 235         'working properly you will be unable to access files with unusual '.
 236         'names in repositories, among other issues.'.
 237         "\n\n".
 238         '(This problem can be caused by a missing "B" in your RewriteRule.)',
 239         $send_path,
 240         $expect_path,
 241         $actual_path);
 242
 243       $this->newIssue('webserver.rewrites')
 244         ->setName(pht('HTTP Path Rewriting Incorrect'))
 245         ->setSummary(pht('Your webserver is rewriting paths improperly.'))
 246         ->setMessage($message);
 247     }
 248
 249     $actual_key = pht('<none>');
 250     $actual_value = pht('<none>');
 251     foreach (idx($structure, 'params', array()) as $pair) {
 252       if (idx($pair, 'name') == $expect_key) {
 253         $actual_key = idx($pair, 'name');
 254         $actual_value = idx($pair, 'value');
 255         break;
 256       }
 257     }
 258
 259     if (($expect_key !== $actual_key) || ($expect_value !== $actual_value)) {
 260       $message = pht(
 261         'Phabricator sent itself a test request with an HTTP GET parameter, '.
 262         'but the parameter was not transmitted. Sent "%s" with value "%s", '.
 263         'got "%s" with value "%s".'.
 264         "\n\n".
 265         'Your webserver is configured incorrectly and large parts of '.
 266         'Phabricator will not work until this issue is corrected.'.
 267         "\n\n".
 268         '(This problem can be caused by a missing "QSA" in your RewriteRule.)',
 269         $expect_key,
 270         $expect_value,
 271         $actual_key,
 272         $actual_value);
 273
 274       $this->newIssue('webserver.parameters')
 275         ->setName(pht('HTTP Parameters Not Transmitting'))
 276         ->setSummary(
 277           pht('Your webserver is not handling GET parameters properly.'))
 278         ->setMessage($message);
 279     }
 280
 281     if ($gzip_future) {
 282       $this->checkGzipResponse(
 283         $gzip_future,
 284         $gzip_uncompressed,
 285         $gzip_compressed);
 286     }
 287   }
 288
 289   private function checkGzipResponse(
 290     Future $future,
 291     $uncompressed,
 292     $compressed) {
 293
 294     try {
 295       list($body, $headers) = $future->resolvex();
 296     } catch (Exception $ex) {
 297       return;
 298     }
 299
 300     try {
 301       $structure = phutil_json_decode(trim($body));
 302     } catch (Exception $ex) {
 303       return;
 304     }
 305
 306     $raw_body = idx($structure, 'raw.base64');
 307     $raw_body = @base64_decode($raw_body);
 308
 309     // The server received the exact compressed bytes we expected it to, so
 310     // everything is working great.
 311     if ($raw_body === $compressed) {
 312       return;
 313     }
 314
 315     // If the server received a prefix of the raw uncompressed string, it
 316     // is almost certainly configured to decompress responses inline. Guide
 317     // users to this problem narrowly.
 318
 319     // Otherwise, something is wrong but we don't have much of a clue what.
 320
 321     $message = array();
 322     $message[] = pht(
 323       'Phabricator sent itself a test request that was compressed with '.
 324       '"Content-Encoding: gzip", but received different bytes than it '.
 325       'sent.');
 326
 327     $prefix_len = min(strlen($raw_body), strlen($uncompressed));
 328     if ($prefix_len > 16 && !strncmp($raw_body, $uncompressed, $prefix_len)) {
 329       $message[] = pht(
 330         'The request body that the server received had already been '.
 331         'decompressed. This strongly suggests your webserver is configured '.
 332         'to decompress requests inline, before they reach PHP.');
 333       $message[] = pht(
 334         'If you are using Apache, your server may be configured with '.
 335         '"SetInputFilter DEFLATE". This directive destructively mangles '.
 336         'requests and emits them with "Content-Length" and '.
 337         '"Content-Encoding" headers that no longer match the data in the '.
 338         'request body.');
 339     } else {
 340       $message[] = pht(
 341         'This suggests your webserver is configured to decompress or mangle '.
 342         'compressed requests.');
 343
 344       $message[] = pht(
 345         'The request body Phabricator sent began:');
 346       $message[] = $this->snipBytes($compressed);
 347
 348       $message[] = pht(
 349         'The request body Phabricator received began:');
 350       $message[] = $this->snipBytes($raw_body);
 351     }
 352
 353     $message[] = pht(
 354       'Identify the component in your webserver configuration which is '.
 355       'decompressing or mangling requests and disable it. Phabricator '.
 356       'will not work properly until you do.');
 357
 358     $message = phutil_implode_html("\n\n", $message);
 359
 360     $this->newIssue('webserver.accept-gzip')
 361       ->setName(pht('Compressed Requests Not Received Properly'))
 362       ->setSummary(
 363         pht(
 364           'Your webserver is not handling compressed request bodies '.
 365           'properly.'))
 366       ->setMessage($message);
 367   }
 368
 369   private function snipBytes($raw) {
 370     if (!strlen($raw)) {
 371       $display = pht('<empty>');
 372     } else {
 373       $snip = substr($raw, 0, 24);
 374       $display = phutil_loggable_string($snip);
 375
 376       if (strlen($snip) < strlen($raw)) {
 377         $display .= '...';
 378       }
 379     }
 380
 381     return phutil_tag('tt', array(), $display);
 382   }
 383
 384 }