summaryrefslogtreecommitdiffstats
path: root/Source/WebCore/loader/CrossOriginAccessControl.cpp
blob: 671c185e1b1afbffff6b5ee2b0c58ac75f172ab6 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
/*
 * 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 "HTTPParsers.h"
#include "ResourceResponse.h"
#include "SecurityOrigin.h"
#include <wtf/HashSet.h>
#include <wtf/Threading.h>
#include <wtf/text/AtomicString.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")
        || equalIgnoringCase(name, "origin"))
        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 PassOwnPtr<HTTPHeaderSet> createAllowedCrossOriginResponseHeadersSet()
{
    OwnPtr<HTTPHeaderSet> headerSet = adoptPtr(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.release();
}

bool isOnAccessControlResponseHeaderWhitelist(const String& name)
{
    AtomicallyInitializedStatic(HTTPHeaderSet*, allowedCrossOriginResponseHeaders = createAllowedCrossOriginResponseHeadersSet().leakPtr());

    return allowedCrossOriginResponseHeaders->contains(name);
}

void updateRequestForAccessControl(ResourceRequest& request, SecurityOrigin* securityOrigin, bool allowCredentials)
{
    request.removeCredentials();
    request.setAllowCookies(allowCredentials);
    request.setHTTPOrigin(securityOrigin->toString());
}

ResourceRequest createAccessControlPreflightRequest(const ResourceRequest& request, SecurityOrigin* securityOrigin, bool allowCredentials)
{
    ResourceRequest preflightRequest(request.url());
    updateRequestForAccessControl(preflightRequest, securityOrigin, allowCredentials);
    preflightRequest.setHTTPMethod("OPTIONS");
    preflightRequest.setHTTPHeaderField("Access-Control-Request-Method", request.httpMethod());
    preflightRequest.setPriority(request.priority());

    const HTTPHeaderMap& requestHeaderFields = request.httpHeaderFields();

    if (requestHeaderFields.size() > 0) {
        Vector<UChar> headerBuffer;
        HTTPHeaderMap::const_iterator it = requestHeaderFields.begin();
        append(headerBuffer, it->first);
        ++it;

        HTTPHeaderMap::const_iterator end = requestHeaderFields.end();
        for (; it != end; ++it) {
            headerBuffer.append(',');
            headerBuffer.append(' ');
            append(headerBuffer, it->first);
        }

        preflightRequest.setHTTPHeaderField("Access-Control-Request-Headers", String::adopt(headerBuffer));
    }

    return preflightRequest;
}

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