OLD | NEW |
| (Empty) |
1 // Copyright (c) 2012 The Chromium Authors. All rights reserved. | |
2 // Use of this source code is governed by a BSD-style license that can be | |
3 // found in the LICENSE file. | |
4 | |
5 #include "content/browser/child_process_security_policy.h" | |
6 | |
7 #include "base/file_path.h" | |
8 #include "base/logging.h" | |
9 #include "base/metrics/histogram.h" | |
10 #include "base/platform_file.h" | |
11 #include "base/stl_util.h" | |
12 #include "base/string_util.h" | |
13 #include "content/browser/site_instance_impl.h" | |
14 #include "content/public/browser/content_browser_client.h" | |
15 #include "content/public/common/bindings_policy.h" | |
16 #include "content/public/common/url_constants.h" | |
17 #include "googleurl/src/gurl.h" | |
18 #include "net/url_request/url_request.h" | |
19 #include "webkit/fileapi/isolated_context.h" | |
20 | |
21 using content::SiteInstance; | |
22 | |
23 static const int kReadFilePermissions = | |
24 base::PLATFORM_FILE_OPEN | | |
25 base::PLATFORM_FILE_READ | | |
26 base::PLATFORM_FILE_EXCLUSIVE_READ | | |
27 base::PLATFORM_FILE_ASYNC; | |
28 | |
29 static const int kEnumerateDirectoryPermissions = | |
30 kReadFilePermissions | | |
31 base::PLATFORM_FILE_ENUMERATE; | |
32 | |
33 // The SecurityState class is used to maintain per-child process security state | |
34 // information. | |
35 class ChildProcessSecurityPolicy::SecurityState { | |
36 public: | |
37 SecurityState() | |
38 : enabled_bindings_(0), | |
39 can_read_raw_cookies_(false) { } | |
40 | |
41 ~SecurityState() { | |
42 scheme_policy_.clear(); | |
43 fileapi::IsolatedContext* isolated_context = | |
44 fileapi::IsolatedContext::GetInstance(); | |
45 for (FileSystemSet::iterator iter = access_granted_filesystems_.begin(); | |
46 iter != access_granted_filesystems_.end(); | |
47 ++iter) { | |
48 isolated_context->RevokeIsolatedFileSystem(*iter); | |
49 } | |
50 UMA_HISTOGRAM_COUNTS("ChildProcessSecurityPolicy.PerChildFilePermissions", | |
51 file_permissions_.size()); | |
52 } | |
53 | |
54 // Grant permission to request URLs with the specified scheme. | |
55 void GrantScheme(const std::string& scheme) { | |
56 scheme_policy_[scheme] = true; | |
57 } | |
58 | |
59 // Revoke permission to request URLs with the specified scheme. | |
60 void RevokeScheme(const std::string& scheme) { | |
61 scheme_policy_[scheme] = false; | |
62 } | |
63 | |
64 // Grant certain permissions to a file. | |
65 void GrantPermissionsForFile(const FilePath& file, int permissions) { | |
66 FilePath stripped = file.StripTrailingSeparators(); | |
67 file_permissions_[stripped] |= permissions; | |
68 UMA_HISTOGRAM_COUNTS("ChildProcessSecurityPolicy.FilePermissionPathLength", | |
69 stripped.value().size()); | |
70 } | |
71 | |
72 // Revokes all permissions granted to a file. | |
73 void RevokeAllPermissionsForFile(const FilePath& file) { | |
74 file_permissions_.erase(file.StripTrailingSeparators()); | |
75 } | |
76 | |
77 // Grant certain permissions to a file. | |
78 void GrantAccessFileSystem(const std::string& filesystem_id) { | |
79 access_granted_filesystems_.insert(filesystem_id); | |
80 } | |
81 | |
82 void GrantBindings(int bindings) { | |
83 enabled_bindings_ |= bindings; | |
84 } | |
85 | |
86 void GrantReadRawCookies() { | |
87 can_read_raw_cookies_ = true; | |
88 } | |
89 | |
90 void RevokeReadRawCookies() { | |
91 can_read_raw_cookies_ = false; | |
92 } | |
93 | |
94 // Determine whether permission has been granted to request url. | |
95 // Schemes that have not been granted default to being denied. | |
96 bool CanRequestURL(const GURL& url) { | |
97 SchemeMap::const_iterator judgment(scheme_policy_.find(url.scheme())); | |
98 | |
99 if (judgment == scheme_policy_.end()) | |
100 return false; // Unmentioned schemes are disallowed. | |
101 | |
102 return judgment->second; | |
103 } | |
104 | |
105 // Determine if the certain permissions have been granted to a file. | |
106 bool HasPermissionsForFile(const FilePath& file, int permissions) { | |
107 FilePath current_path = file.StripTrailingSeparators(); | |
108 FilePath last_path; | |
109 while (current_path != last_path) { | |
110 if (file_permissions_.find(current_path) != file_permissions_.end()) | |
111 return (file_permissions_[current_path] & permissions) == permissions; | |
112 last_path = current_path; | |
113 current_path = current_path.DirName(); | |
114 } | |
115 | |
116 return false; | |
117 } | |
118 | |
119 bool CanUseCookiesForOrigin(const GURL& gurl) { | |
120 if (origin_lock_.is_empty()) | |
121 return true; | |
122 GURL site_gurl = SiteInstanceImpl::GetSiteForURL(NULL, gurl); | |
123 return origin_lock_ == site_gurl; | |
124 } | |
125 | |
126 void LockToOrigin(const GURL& gurl) { | |
127 origin_lock_ = gurl; | |
128 } | |
129 | |
130 bool has_web_ui_bindings() const { | |
131 return enabled_bindings_ & content::BINDINGS_POLICY_WEB_UI; | |
132 } | |
133 | |
134 bool can_read_raw_cookies() const { | |
135 return can_read_raw_cookies_; | |
136 } | |
137 | |
138 private: | |
139 typedef std::map<std::string, bool> SchemeMap; | |
140 typedef std::map<FilePath, int> FileMap; // bit-set of PlatformFileFlags | |
141 typedef std::set<std::string> FileSystemSet; | |
142 | |
143 // Maps URL schemes to whether permission has been granted or revoked: | |
144 // |true| means the scheme has been granted. | |
145 // |false| means the scheme has been revoked. | |
146 // If a scheme is not present in the map, then it has never been granted | |
147 // or revoked. | |
148 SchemeMap scheme_policy_; | |
149 | |
150 // The set of files the child process is permited to upload to the web. | |
151 FileMap file_permissions_; | |
152 | |
153 int enabled_bindings_; | |
154 | |
155 bool can_read_raw_cookies_; | |
156 | |
157 GURL origin_lock_; | |
158 | |
159 // The set of isolated filesystems the child process is permitted to access. | |
160 FileSystemSet access_granted_filesystems_; | |
161 | |
162 DISALLOW_COPY_AND_ASSIGN(SecurityState); | |
163 }; | |
164 | |
165 ChildProcessSecurityPolicy::ChildProcessSecurityPolicy() { | |
166 // We know about these schemes and believe them to be safe. | |
167 RegisterWebSafeScheme(chrome::kHttpScheme); | |
168 RegisterWebSafeScheme(chrome::kHttpsScheme); | |
169 RegisterWebSafeScheme(chrome::kFtpScheme); | |
170 RegisterWebSafeScheme(chrome::kDataScheme); | |
171 RegisterWebSafeScheme("feed"); | |
172 RegisterWebSafeScheme(chrome::kBlobScheme); | |
173 RegisterWebSafeScheme(chrome::kFileSystemScheme); | |
174 | |
175 // We know about the following pseudo schemes and treat them specially. | |
176 RegisterPseudoScheme(chrome::kAboutScheme); | |
177 RegisterPseudoScheme(chrome::kJavaScriptScheme); | |
178 RegisterPseudoScheme(chrome::kViewSourceScheme); | |
179 } | |
180 | |
181 ChildProcessSecurityPolicy::~ChildProcessSecurityPolicy() { | |
182 web_safe_schemes_.clear(); | |
183 pseudo_schemes_.clear(); | |
184 STLDeleteContainerPairSecondPointers(security_state_.begin(), | |
185 security_state_.end()); | |
186 security_state_.clear(); | |
187 } | |
188 | |
189 // static | |
190 ChildProcessSecurityPolicy* ChildProcessSecurityPolicy::GetInstance() { | |
191 return Singleton<ChildProcessSecurityPolicy>::get(); | |
192 } | |
193 | |
194 void ChildProcessSecurityPolicy::Add(int child_id) { | |
195 base::AutoLock lock(lock_); | |
196 AddChild(child_id); | |
197 } | |
198 | |
199 void ChildProcessSecurityPolicy::AddWorker(int child_id, | |
200 int main_render_process_id) { | |
201 base::AutoLock lock(lock_); | |
202 AddChild(child_id); | |
203 worker_map_[child_id] = main_render_process_id; | |
204 } | |
205 | |
206 void ChildProcessSecurityPolicy::Remove(int child_id) { | |
207 base::AutoLock lock(lock_); | |
208 if (!security_state_.count(child_id)) | |
209 return; // May be called multiple times. | |
210 | |
211 delete security_state_[child_id]; | |
212 security_state_.erase(child_id); | |
213 worker_map_.erase(child_id); | |
214 } | |
215 | |
216 void ChildProcessSecurityPolicy::RegisterWebSafeScheme( | |
217 const std::string& scheme) { | |
218 base::AutoLock lock(lock_); | |
219 DCHECK(web_safe_schemes_.count(scheme) == 0) << "Add schemes at most once."; | |
220 DCHECK(pseudo_schemes_.count(scheme) == 0) << "Web-safe implies not pseudo."; | |
221 | |
222 web_safe_schemes_.insert(scheme); | |
223 } | |
224 | |
225 bool ChildProcessSecurityPolicy::IsWebSafeScheme(const std::string& scheme) { | |
226 base::AutoLock lock(lock_); | |
227 | |
228 return (web_safe_schemes_.find(scheme) != web_safe_schemes_.end()); | |
229 } | |
230 | |
231 void ChildProcessSecurityPolicy::RegisterPseudoScheme( | |
232 const std::string& scheme) { | |
233 base::AutoLock lock(lock_); | |
234 DCHECK(pseudo_schemes_.count(scheme) == 0) << "Add schemes at most once."; | |
235 DCHECK(web_safe_schemes_.count(scheme) == 0) << | |
236 "Pseudo implies not web-safe."; | |
237 | |
238 pseudo_schemes_.insert(scheme); | |
239 } | |
240 | |
241 bool ChildProcessSecurityPolicy::IsPseudoScheme(const std::string& scheme) { | |
242 base::AutoLock lock(lock_); | |
243 | |
244 return (pseudo_schemes_.find(scheme) != pseudo_schemes_.end()); | |
245 } | |
246 | |
247 void ChildProcessSecurityPolicy::RegisterDisabledSchemes( | |
248 const std::set<std::string>& schemes) { | |
249 base::AutoLock lock(lock_); | |
250 disabled_schemes_ = schemes; | |
251 } | |
252 | |
253 bool ChildProcessSecurityPolicy::IsDisabledScheme(const std::string& scheme) { | |
254 base::AutoLock lock(lock_); | |
255 return disabled_schemes_.find(scheme) != disabled_schemes_.end(); | |
256 } | |
257 | |
258 void ChildProcessSecurityPolicy::GrantRequestURL( | |
259 int child_id, const GURL& url) { | |
260 | |
261 if (!url.is_valid()) | |
262 return; // Can't grant the capability to request invalid URLs. | |
263 | |
264 if (IsWebSafeScheme(url.scheme())) | |
265 return; // The scheme has already been whitelisted for every child process. | |
266 | |
267 if (IsPseudoScheme(url.scheme())) { | |
268 // The view-source scheme is a special case of a pseudo-URL that eventually | |
269 // results in requesting its embedded URL. | |
270 if (url.SchemeIs(chrome::kViewSourceScheme)) { | |
271 // URLs with the view-source scheme typically look like: | |
272 // view-source:http://www.google.com/a | |
273 // In order to request these URLs, the child_id needs to be able to | |
274 // request the embedded URL. | |
275 GrantRequestURL(child_id, GURL(url.path())); | |
276 } | |
277 | |
278 return; // Can't grant the capability to request pseudo schemes. | |
279 } | |
280 | |
281 { | |
282 base::AutoLock lock(lock_); | |
283 SecurityStateMap::iterator state = security_state_.find(child_id); | |
284 if (state == security_state_.end()) | |
285 return; | |
286 | |
287 // If the child process has been commanded to request a scheme, then we | |
288 // grant it the capability to request URLs of that scheme. | |
289 state->second->GrantScheme(url.scheme()); | |
290 } | |
291 } | |
292 | |
293 void ChildProcessSecurityPolicy::GrantReadFile(int child_id, | |
294 const FilePath& file) { | |
295 GrantPermissionsForFile(child_id, file, kReadFilePermissions); | |
296 } | |
297 | |
298 void ChildProcessSecurityPolicy::GrantReadDirectory(int child_id, | |
299 const FilePath& directory) { | |
300 GrantPermissionsForFile(child_id, directory, kEnumerateDirectoryPermissions); | |
301 } | |
302 | |
303 void ChildProcessSecurityPolicy::GrantPermissionsForFile( | |
304 int child_id, const FilePath& file, int permissions) { | |
305 base::AutoLock lock(lock_); | |
306 | |
307 SecurityStateMap::iterator state = security_state_.find(child_id); | |
308 if (state == security_state_.end()) | |
309 return; | |
310 | |
311 state->second->GrantPermissionsForFile(file, permissions); | |
312 } | |
313 | |
314 void ChildProcessSecurityPolicy::RevokeAllPermissionsForFile( | |
315 int child_id, const FilePath& file) { | |
316 base::AutoLock lock(lock_); | |
317 | |
318 SecurityStateMap::iterator state = security_state_.find(child_id); | |
319 if (state == security_state_.end()) | |
320 return; | |
321 | |
322 state->second->RevokeAllPermissionsForFile(file); | |
323 } | |
324 | |
325 void ChildProcessSecurityPolicy::GrantAccessFileSystem( | |
326 int child_id, const std::string& filesystem_id) { | |
327 base::AutoLock lock(lock_); | |
328 | |
329 SecurityStateMap::iterator state = security_state_.find(child_id); | |
330 if (state == security_state_.end()) | |
331 return; | |
332 | |
333 state->second->GrantAccessFileSystem(filesystem_id); | |
334 } | |
335 | |
336 void ChildProcessSecurityPolicy::GrantScheme(int child_id, | |
337 const std::string& scheme) { | |
338 base::AutoLock lock(lock_); | |
339 | |
340 SecurityStateMap::iterator state = security_state_.find(child_id); | |
341 if (state == security_state_.end()) | |
342 return; | |
343 | |
344 state->second->GrantScheme(scheme); | |
345 } | |
346 | |
347 void ChildProcessSecurityPolicy::GrantWebUIBindings(int child_id) { | |
348 base::AutoLock lock(lock_); | |
349 | |
350 SecurityStateMap::iterator state = security_state_.find(child_id); | |
351 if (state == security_state_.end()) | |
352 return; | |
353 | |
354 state->second->GrantBindings(content::BINDINGS_POLICY_WEB_UI); | |
355 | |
356 // Web UI bindings need the ability to request chrome: URLs. | |
357 state->second->GrantScheme(chrome::kChromeUIScheme); | |
358 | |
359 // Web UI pages can contain links to file:// URLs. | |
360 state->second->GrantScheme(chrome::kFileScheme); | |
361 } | |
362 | |
363 void ChildProcessSecurityPolicy::GrantReadRawCookies(int child_id) { | |
364 base::AutoLock lock(lock_); | |
365 | |
366 SecurityStateMap::iterator state = security_state_.find(child_id); | |
367 if (state == security_state_.end()) | |
368 return; | |
369 | |
370 state->second->GrantReadRawCookies(); | |
371 } | |
372 | |
373 void ChildProcessSecurityPolicy::RevokeReadRawCookies(int child_id) { | |
374 base::AutoLock lock(lock_); | |
375 | |
376 SecurityStateMap::iterator state = security_state_.find(child_id); | |
377 if (state == security_state_.end()) | |
378 return; | |
379 | |
380 state->second->RevokeReadRawCookies(); | |
381 } | |
382 | |
383 bool ChildProcessSecurityPolicy::CanRequestURL( | |
384 int child_id, const GURL& url) { | |
385 if (!url.is_valid()) | |
386 return false; // Can't request invalid URLs. | |
387 | |
388 if (IsDisabledScheme(url.scheme())) | |
389 return false; // The scheme is disabled by policy. | |
390 | |
391 if (IsWebSafeScheme(url.scheme())) | |
392 return true; // The scheme has been white-listed for every child process. | |
393 | |
394 if (IsPseudoScheme(url.scheme())) { | |
395 // There are a number of special cases for pseudo schemes. | |
396 | |
397 if (url.SchemeIs(chrome::kViewSourceScheme)) { | |
398 // A view-source URL is allowed if the child process is permitted to | |
399 // request the embedded URL. Careful to avoid pointless recursion. | |
400 GURL child_url(url.path()); | |
401 if (child_url.SchemeIs(chrome::kViewSourceScheme) && | |
402 url.SchemeIs(chrome::kViewSourceScheme)) | |
403 return false; | |
404 | |
405 return CanRequestURL(child_id, child_url); | |
406 } | |
407 | |
408 if (LowerCaseEqualsASCII(url.spec(), chrome::kAboutBlankURL)) | |
409 return true; // Every child process can request <about:blank>. | |
410 | |
411 // URLs like <about:memory> and <about:crash> shouldn't be requestable by | |
412 // any child process. Also, this case covers <javascript:...>, which should | |
413 // be handled internally by the process and not kicked up to the browser. | |
414 return false; | |
415 } | |
416 | |
417 if (!content::GetContentClient()->browser()->IsHandledURL(url) && | |
418 !net::URLRequest::IsHandledURL(url)) { | |
419 return true; // This URL request is destined for ShellExecute. | |
420 } | |
421 | |
422 { | |
423 base::AutoLock lock(lock_); | |
424 | |
425 SecurityStateMap::iterator state = security_state_.find(child_id); | |
426 if (state == security_state_.end()) | |
427 return false; | |
428 | |
429 // Otherwise, we consult the child process's security state to see if it is | |
430 // allowed to request the URL. | |
431 return state->second->CanRequestURL(url); | |
432 } | |
433 } | |
434 | |
435 bool ChildProcessSecurityPolicy::CanReadFile(int child_id, | |
436 const FilePath& file) { | |
437 return HasPermissionsForFile(child_id, file, kReadFilePermissions); | |
438 } | |
439 | |
440 bool ChildProcessSecurityPolicy::CanReadDirectory(int child_id, | |
441 const FilePath& directory) { | |
442 return HasPermissionsForFile(child_id, | |
443 directory, | |
444 kEnumerateDirectoryPermissions); | |
445 } | |
446 | |
447 bool ChildProcessSecurityPolicy::HasPermissionsForFile( | |
448 int child_id, const FilePath& file, int permissions) { | |
449 base::AutoLock lock(lock_); | |
450 bool result = ChildProcessHasPermissionsForFile(child_id, file, permissions); | |
451 if (!result) { | |
452 // If this is a worker thread that has no access to a given file, | |
453 // let's check that its renderer process has access to that file instead. | |
454 WorkerToMainProcessMap::iterator iter = worker_map_.find(child_id); | |
455 if (iter != worker_map_.end() && iter->second != 0) { | |
456 result = ChildProcessHasPermissionsForFile(iter->second, | |
457 file, | |
458 permissions); | |
459 } | |
460 } | |
461 return result; | |
462 } | |
463 | |
464 bool ChildProcessSecurityPolicy::HasWebUIBindings(int child_id) { | |
465 base::AutoLock lock(lock_); | |
466 | |
467 SecurityStateMap::iterator state = security_state_.find(child_id); | |
468 if (state == security_state_.end()) | |
469 return false; | |
470 | |
471 return state->second->has_web_ui_bindings(); | |
472 } | |
473 | |
474 bool ChildProcessSecurityPolicy::CanReadRawCookies(int child_id) { | |
475 base::AutoLock lock(lock_); | |
476 | |
477 SecurityStateMap::iterator state = security_state_.find(child_id); | |
478 if (state == security_state_.end()) | |
479 return false; | |
480 | |
481 return state->second->can_read_raw_cookies(); | |
482 } | |
483 | |
484 void ChildProcessSecurityPolicy::AddChild(int child_id) { | |
485 if (security_state_.count(child_id) != 0) { | |
486 NOTREACHED() << "Add child process at most once."; | |
487 return; | |
488 } | |
489 | |
490 security_state_[child_id] = new SecurityState(); | |
491 } | |
492 | |
493 bool ChildProcessSecurityPolicy::ChildProcessHasPermissionsForFile( | |
494 int child_id, const FilePath& file, int permissions) { | |
495 SecurityStateMap::iterator state = security_state_.find(child_id); | |
496 if (state == security_state_.end()) | |
497 return false; | |
498 return state->second->HasPermissionsForFile(file, permissions); | |
499 } | |
500 | |
501 bool ChildProcessSecurityPolicy::CanUseCookiesForOrigin(int child_id, | |
502 const GURL& gurl) { | |
503 base::AutoLock lock(lock_); | |
504 SecurityStateMap::iterator state = security_state_.find(child_id); | |
505 if (state == security_state_.end()) | |
506 return false; | |
507 return state->second->CanUseCookiesForOrigin(gurl); | |
508 } | |
509 | |
510 void ChildProcessSecurityPolicy::LockToOrigin(int child_id, const GURL& gurl) { | |
511 // "gurl" can be currently empty in some cases, such as file://blah. | |
512 DCHECK(SiteInstanceImpl::GetSiteForURL(NULL, gurl) == gurl); | |
513 base::AutoLock lock(lock_); | |
514 SecurityStateMap::iterator state = security_state_.find(child_id); | |
515 DCHECK(state != security_state_.end()); | |
516 state->second->LockToOrigin(gurl); | |
517 } | |
OLD | NEW |