components/data_reduction_proxy/common/data_reduction_proxy_headers.h

   1 // Copyright 2014 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 #ifndef COMPONENTS_DATA_REDUCTION_PROXY_COMMON_DATA_REDUCTION_PROXY_HEADERS_H_
   6 #define COMPONENTS_DATA_REDUCTION_PROXY_COMMON_DATA_REDUCTION_PROXY_HEADERS_H_
   7
   8 #include <string>
   9
  10 #include "base/macros.h"
  11 #include "base/time/time.h"
  12 #include "net/proxy/proxy_service.h"
  13
  14 namespace net {
  15
  16 class HttpResponseHeaders;
  17
  18 }  // namespace net
  19
  20 namespace data_reduction_proxy {
  21
  22 // Values of the UMA DataReductionProxy.BypassType{Primary|Fallback}
  23 // and DataReductionProxy.BlockType{Primary|Fallback} histograms.
  24 // This enum must remain synchronized with the enum of the same
  25 // name in metrics/histograms/histograms.xml.
  26 enum DataReductionProxyBypassType {
  27   // Bypass due to explicit instruction for the current request.
  28   BYPASS_EVENT_TYPE_CURRENT = 0,
  29
  30   // Bypass the proxy for less than one minute.
  31   BYPASS_EVENT_TYPE_SHORT = 1,
  32
  33   // Bypass the proxy for one to five minutes.
  34   BYPASS_EVENT_TYPE_MEDIUM = 2,
  35
  36   // Bypass the proxy for more than five minutes.
  37   BYPASS_EVENT_TYPE_LONG = 3,
  38
  39   // Bypass due to a 4xx missing via header.
  40   BYPASS_EVENT_TYPE_MISSING_VIA_HEADER_4XX = 4,
  41
  42   // Bypass due to other missing via header, excluding 4xx errors.
  43   BYPASS_EVENT_TYPE_MISSING_VIA_HEADER_OTHER = 5,
  44
  45   // Bypass due to 407 response from proxy without a challenge.
  46   BYPASS_EVENT_TYPE_MALFORMED_407 = 6,
  47
  48   // Bypass due to a 500 internal server error
  49   BYPASS_EVENT_TYPE_STATUS_500_HTTP_INTERNAL_SERVER_ERROR = 7,
  50
  51   // Bypass because the request URI was too long.
  52   BYPASS_EVENT_TYPE_STATUS_502_HTTP_BAD_GATEWAY = 8,
  53
  54   // Bypass due to a 503 response.
  55   BYPASS_EVENT_TYPE_STATUS_503_HTTP_SERVICE_UNAVAILABLE = 9,
  56
  57   // Bypass due to any network error.
  58   BYPASS_EVENT_TYPE_NETWORK_ERROR = 10,
  59
  60   // This must always be last.
  61   BYPASS_EVENT_TYPE_MAX = 11
  62 };
  63
  64 // Contains instructions contained in the Chrome-Proxy header.
  65 struct DataReductionProxyInfo {
  66   DataReductionProxyInfo()
  67       : bypass_all(false), mark_proxies_as_bad(false) {}
  68
  69   // True if Chrome should bypass all available data reduction proxies. False
  70   // if only the currently connected data reduction proxy should be bypassed.
  71   bool bypass_all;
  72
  73   // True iff Chrome should mark the data reduction proxy or proxies as bad for
  74   // the period of time specified in |bypass_duration|.
  75   bool mark_proxies_as_bad;
  76
  77   // Amount of time to bypass the data reduction proxy or proxies. This value is
  78   // ignored if |mark_proxies_as_bad| is false.
  79   base::TimeDelta bypass_duration;
  80 };
  81
  82 // Returns true if the Chrome-Proxy header is present and contains a bypass
  83 // delay. Sets |proxy_info->bypass_duration| to the specified delay if greater
  84 // than 0, and to 0 otherwise to indicate that the default proxy delay
  85 // (as specified in |ProxyList::UpdateRetryInfoOnFallback|) should be used.
  86 // If all available data reduction proxies should by bypassed, |bypass_all| is
  87 // set to true. |proxy_info| must be non-NULL.
  88 bool ParseHeadersAndSetProxyInfo(const net::HttpResponseHeaders* headers,
  89                                  DataReductionProxyInfo* proxy_info);
  90
  91 // Returns true if the response contains the data reduction proxy Via header
  92 // value. If non-NULL, sets |has_intermediary| to true if another server added
  93 // a Via header after the data reduction proxy, and to false otherwise. Used to
  94 // check the integrity of data reduction proxy responses and whether there are
  95 // other middleboxes between the data reduction proxy and the client.
  96 bool HasDataReductionProxyViaHeader(const net::HttpResponseHeaders* headers,
  97                                     bool* has_intermediary);
  98
  99 // Returns the reason why the Chrome proxy should be bypassed or not, and
 100 // populates |proxy_info| with information on how long to bypass if
 101 // applicable.
 102 DataReductionProxyBypassType GetDataReductionProxyBypassType(
 103     const net::HttpResponseHeaders* headers,
 104     DataReductionProxyInfo* proxy_info);
 105
 106 // Searches for the specified Chrome-Proxy action, and if present saves its
 107 // value as a string in |action_value|. Only returns the first one and ignores
 108 // the rest if multiple actions match |action_prefix|.
 109 bool GetDataReductionProxyActionValue(
 110     const net::HttpResponseHeaders* headers,
 111     const std::string& action_prefix,
 112     std::string* action_value);
 113
 114 // Searches for the specified Chrome-Proxy action, and if present interprets
 115 // its value as a duration in seconds.
 116 bool ParseHeadersAndSetBypassDuration(const net::HttpResponseHeaders* headers,
 117                                       const std::string& action_prefix,
 118                                       base::TimeDelta* bypass_duration);
 119
 120 // Gets the fingerprint of the Chrome-Proxy header.
 121 bool GetDataReductionProxyActionFingerprintChromeProxy(
 122     const net::HttpResponseHeaders* headers,
 123     std::string* chrome_proxy_fingerprint);
 124
 125 // Gets the fingerprint of the Via header.
 126 bool GetDataReductionProxyActionFingerprintVia(
 127     const net::HttpResponseHeaders* headers,
 128     std::string* via_fingerprint);
 129
 130 // Gets the fingerprint of a list of headers.
 131 bool GetDataReductionProxyActionFingerprintOtherHeaders(
 132     const net::HttpResponseHeaders* headers,
 133     std::string* other_headers_fingerprint);
 134
 135 // Gets the fingerprint of Content-Length header.
 136 bool GetDataReductionProxyActionFingerprintContentLength(
 137     const net::HttpResponseHeaders* headers,
 138     std::string* content_length_fingerprint);
 139
 140 // Returns values of the Chrome-Proxy header, but with its fingerprint removed.
 141 void GetDataReductionProxyHeaderWithFingerprintRemoved(
 142     const net::HttpResponseHeaders* headers,
 143     std::vector<std::string>* values);
 144
 145 }  // namespace data_reduction_proxy
 146 #endif  // COMPONENTS_DATA_REDUCTION_PROXY_COMMON_DATA_REDUCTION_PROXY_HEADERS_H_