WebCore/loader/CrossOriginAccessControl.cpp
changeset 0 4f2f89ce4247
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/WebCore/loader/CrossOriginAccessControl.cpp	Fri Sep 17 09:02:29 2010 +0300
@@ -0,0 +1,127 @@
+/*
+ * Copyright (C) 2008 Apple Inc. All Rights Reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE COMPUTER, INC. OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
+ * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 
+ *
+ */
+
+#include "config.h"
+#include "CrossOriginAccessControl.h"
+
+#include "AtomicString.h"
+#include "HTTPParsers.h"
+#include "ResourceResponse.h"
+#include "SecurityOrigin.h"
+#include <wtf/Threading.h>
+
+namespace WebCore {
+
+bool isOnAccessControlSimpleRequestMethodWhitelist(const String& method)
+{
+    return method == "GET" || method == "HEAD" || method == "POST";
+}
+
+bool isOnAccessControlSimpleRequestHeaderWhitelist(const String& name, const String& value)
+{
+    if (equalIgnoringCase(name, "accept") || equalIgnoringCase(name, "accept-language") || equalIgnoringCase(name, "content-language"))
+        return true;
+
+    // Preflight is required for MIME types that can not be sent via form submission.
+    if (equalIgnoringCase(name, "content-type")) {
+        String mimeType = extractMIMETypeFromMediaType(value);
+        return equalIgnoringCase(mimeType, "application/x-www-form-urlencoded")
+            || equalIgnoringCase(mimeType, "multipart/form-data")
+            || equalIgnoringCase(mimeType, "text/plain");
+    }
+
+    return false;
+}
+
+bool isSimpleCrossOriginAccessRequest(const String& method, const HTTPHeaderMap& headerMap)
+{
+    if (!isOnAccessControlSimpleRequestMethodWhitelist(method))
+        return false;
+
+    HTTPHeaderMap::const_iterator end = headerMap.end();
+    for (HTTPHeaderMap::const_iterator it = headerMap.begin(); it != end; ++it) {
+        if (!isOnAccessControlSimpleRequestHeaderWhitelist(it->first, it->second))
+            return false;
+    }
+
+    return true;
+}
+
+typedef HashSet<String, CaseFoldingHash> HTTPHeaderSet;
+static HTTPHeaderSet* createAllowedCrossOriginResponseHeadersSet()
+{
+    HTTPHeaderSet* headerSet = new HashSet<String, CaseFoldingHash>;
+    
+    headerSet->add("cache-control");
+    headerSet->add("content-language");
+    headerSet->add("content-type");
+    headerSet->add("expires");
+    headerSet->add("last-modified");
+    headerSet->add("pragma");
+
+    return headerSet;
+}
+
+bool isOnAccessControlResponseHeaderWhitelist(const String& name)
+{
+    AtomicallyInitializedStatic(HTTPHeaderSet*, allowedCrossOriginResponseHeaders = createAllowedCrossOriginResponseHeadersSet());
+
+    return allowedCrossOriginResponseHeaders->contains(name);
+}
+
+bool passesAccessControlCheck(const ResourceResponse& response, bool includeCredentials, SecurityOrigin* securityOrigin, String& errorDescription)
+{
+    // A wildcard Access-Control-Allow-Origin can not be used if credentials are to be sent,
+    // even with Access-Control-Allow-Credentials set to true.
+    const String& accessControlOriginString = response.httpHeaderField("Access-Control-Allow-Origin");
+    if (accessControlOriginString == "*" && !includeCredentials)
+        return true;
+
+    if (securityOrigin->isUnique()) {
+        errorDescription = "Cannot make any requests from " + securityOrigin->toString() + ".";
+        return false;
+    }
+
+    // FIXME: Access-Control-Allow-Origin can contain a list of origins.
+    RefPtr<SecurityOrigin> accessControlOrigin = SecurityOrigin::createFromString(accessControlOriginString);
+    if (!accessControlOrigin->isSameSchemeHostPort(securityOrigin)) {
+        errorDescription = (accessControlOriginString == "*") ? "Cannot use wildcard in Access-Control-Allow-Origin when credentials flag is true."
+            : "Origin " + securityOrigin->toString() + " is not allowed by Access-Control-Allow-Origin.";
+        return false;
+    }
+
+    if (includeCredentials) {
+        const String& accessControlCredentialsString = response.httpHeaderField("Access-Control-Allow-Credentials");
+        if (accessControlCredentialsString != "true") {
+            errorDescription = "Credentials flag is true, but Access-Control-Allow-Credentials is not \"true\".";
+            return false;
+        }
+    }
+
+    return true;
+}
+
+} // namespace WebCore