--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/WebCore/loader/CrossOriginPreflightResultCache.cpp	Fri Sep 17 09:02:29 2010 +0300
@@ -0,0 +1,192 @@
+/*
+ * Copyright (C) 2008, 2009 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 "CrossOriginPreflightResultCache.h"
+
+#include "CrossOriginAccessControl.h"
+#include "ResourceResponse.h"
+#include <wtf/CurrentTime.h>
+#include <wtf/StdLibExtras.h>
+#include <wtf/Threading.h>
+
+namespace WebCore {
+
+using namespace std;
+
+// These values are at the discretion of the user agent.
+static const unsigned defaultPreflightCacheTimeoutSeconds = 5;
+static const unsigned maxPreflightCacheTimeoutSeconds = 600; // Should be short enough to minimize the risk of using a poisoned cache after switching to a secure network.
+
+static bool parseAccessControlMaxAge(const String& string, unsigned& expiryDelta)
+{
+    // FIXME: this will not do the correct thing for a number starting with a '+'
+    bool ok = false;
+    expiryDelta = string.toUIntStrict(&ok);
+    return ok;
+}
+
+template<class HashType>
+static void addToAccessControlAllowList(const String& string, unsigned start, unsigned end, HashSet<String, HashType>& set)
+{
+    StringImpl* stringImpl = string.impl();
+    if (!stringImpl)
+        return;
+
+    // Skip white space from start.
+    while (start <= end && isSpaceOrNewline((*stringImpl)[start]))
+        ++start;
+
+    // only white space
+    if (start > end) 
+        return;
+
+    // Skip white space from end.
+    while (end && isSpaceOrNewline((*stringImpl)[end]))
+        --end;
+
+    set.add(string.substring(start, end - start + 1));
+}
+
+template<class HashType>
+static bool parseAccessControlAllowList(const String& string, HashSet<String, HashType>& set)
+{
+    int start = 0;
+    int end;
+    while ((end = string.find(',', start)) != -1) {
+        if (start == end)
+            return false;
+
+        addToAccessControlAllowList(string, start, end - 1, set);
+        start = end + 1;
+    }
+    if (start != static_cast<int>(string.length()))
+        addToAccessControlAllowList(string, start, string.length() - 1, set);
+
+    return true;
+}
+
+bool CrossOriginPreflightResultCacheItem::parse(const ResourceResponse& response, String& errorDescription)
+{
+    m_methods.clear();
+    if (!parseAccessControlAllowList(response.httpHeaderField("Access-Control-Allow-Methods"), m_methods)) {
+        errorDescription = "Cannot parse Access-Control-Allow-Methods response header field.";
+        return false;
+    }
+
+    m_headers.clear();
+    if (!parseAccessControlAllowList(response.httpHeaderField("Access-Control-Allow-Headers"), m_headers)) {
+        errorDescription = "Cannot parse Access-Control-Allow-Headers response header field.";
+        return false;
+    }
+
+    unsigned expiryDelta;
+    if (parseAccessControlMaxAge(response.httpHeaderField("Access-Control-Max-Age"), expiryDelta)) {
+        if (expiryDelta > maxPreflightCacheTimeoutSeconds)
+            expiryDelta = maxPreflightCacheTimeoutSeconds;
+    } else
+        expiryDelta = defaultPreflightCacheTimeoutSeconds;
+
+    m_absoluteExpiryTime = currentTime() + expiryDelta;
+    return true;
+}
+
+bool CrossOriginPreflightResultCacheItem::allowsCrossOriginMethod(const String& method, String& errorDescription) const
+{
+    if (m_methods.contains(method) || isOnAccessControlSimpleRequestMethodWhitelist(method))
+        return true;
+
+    errorDescription = "Method " + method + " is not allowed by Access-Control-Allow-Methods.";
+    return false;
+}
+
+bool CrossOriginPreflightResultCacheItem::allowsCrossOriginHeaders(const HTTPHeaderMap& requestHeaders, String& errorDescription) const
+{
+    HTTPHeaderMap::const_iterator end = requestHeaders.end();
+    for (HTTPHeaderMap::const_iterator it = requestHeaders.begin(); it != end; ++it) {
+        if (!m_headers.contains(it->first) && !isOnAccessControlSimpleRequestHeaderWhitelist(it->first, it->second)) {
+            errorDescription = "Request header field " + it->first + " is not allowed by Access-Control-Allow-Headers.";
+            return false;
+        }
+    }
+    return true;
+}
+
+bool CrossOriginPreflightResultCacheItem::allowsRequest(bool includeCredentials, const String& method, const HTTPHeaderMap& requestHeaders) const
+{
+    String ignoredExplanation;
+    if (m_absoluteExpiryTime < currentTime())
+        return false;
+    if (includeCredentials && !m_credentials)
+        return false;
+    if (!allowsCrossOriginMethod(method, ignoredExplanation))
+        return false;
+    if (!allowsCrossOriginHeaders(requestHeaders, ignoredExplanation))
+        return false;
+    return true;
+}
+
+CrossOriginPreflightResultCache& CrossOriginPreflightResultCache::shared()
+{
+    DEFINE_STATIC_LOCAL(CrossOriginPreflightResultCache, cache, ());
+    ASSERT(isMainThread());
+    return cache;
+}
+
+void CrossOriginPreflightResultCache::appendEntry(const String& origin, const KURL& url, PassOwnPtr<CrossOriginPreflightResultCacheItem> preflightResult)
+{
+    ASSERT(isMainThread());
+    CrossOriginPreflightResultCacheItem* resultPtr = preflightResult.leakPtr();
+    pair<CrossOriginPreflightResultHashMap::iterator, bool> addResult = m_preflightHashMap.add(make_pair(origin, url), resultPtr);
+    if (!addResult.second) {
+        // FIXME: We need to delete the old value before replacing with the new one.
+        addResult.first->second = resultPtr;
+    }
+}
+
+bool CrossOriginPreflightResultCache::canSkipPreflight(const String& origin, const KURL& url, bool includeCredentials, const String& method, const HTTPHeaderMap& requestHeaders)
+{
+    ASSERT(isMainThread());
+    CrossOriginPreflightResultHashMap::iterator cacheIt = m_preflightHashMap.find(std::make_pair(origin, url));
+    if (cacheIt == m_preflightHashMap.end())
+        return false;
+
+    if (cacheIt->second->allowsRequest(includeCredentials, method, requestHeaders))
+        return true;
+
+    delete cacheIt->second;
+    m_preflightHashMap.remove(cacheIt);
+    return false;
+}
+
+void CrossOriginPreflightResultCache::empty()
+{
+    ASSERT(isMainThread());
+    deleteAllValues(m_preflightHashMap);
+    m_preflightHashMap.clear();
+}
+
+} // namespace WebCore