Revert of Modify data_reduction_proxy_header to support tamper detection...

Revert of Modify data_reduction_proxy_header to support tamper detection logic. (https://codereview.chromium.org/387353003/)

Reason for revert:
Causes DataReductionProxyHeadersTest.GetDataReductionProxyHeaderWithFingerprintRemoved to timeout on the bots.

TBR=bengr1@chromium.org, tonyg@chromium.org, bolian@chromium.org, yfriedman@chromium.org
NOTREECHECKS=true
NOTRY=true
BUG=381907

Original issue's description:
> 1. Adds action-parsing functionality for data reduction proxy header.
> 
> 2. Adds a couple of functions to return different fingerprint value for tamper detection.
> 
> 3. Adds a function to remove Chrome-Proxy header's fingerprint from its header values, and return the rest of header values.
> 
> 4. Changes HasDataReductionProxyViaHeader to also tell 
> whether data reduction proxy Via header occurs at the last 
> or not.
> 
> 
> BUG=381907
> 
> Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=287561

Review URL: https://codereview.chromium.org/444723003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@287608 0039d316-1c4b-4281-b951-d872f2087c98

chrome/browser/android/intercept_download_resource_throttle.cc

@@ -62,7 +62,7 @@ void InterceptDownloadResourceThrottle::ProcessDownloadRequest() {
     if (headers.HasHeader(net::HttpRequestHeaders::kAuthorization) ||
         !(request_->response_info().headers &&
             data_reduction_proxy::HasDataReductionProxyViaHeader(
-                request_->response_info().headers, NULL))) {
+                request_->response_info().headers))) {
       return;
     }
 #else

chrome/renderer/page_load_histograms.cc

@@ -177,8 +177,7 @@ bool DataReductionProxyWasUsed(WebFrame* frame) {
   std::replace(headers.begin(), headers.end(), '\n', '\0');
   scoped_refptr<net::HttpResponseHeaders> response_headers(
       new net::HttpResponseHeaders(headers));
-  return data_reduction_proxy::HasDataReductionProxyViaHeader(
-      response_headers, NULL);
+  return data_reduction_proxy::HasDataReductionProxyViaHeader(response_headers);
 }
 
 // Returns true if the provided URL is a referrer string that came from

components/data_reduction_proxy/browser/data_reduction_proxy_metrics.cc

@@ -315,7 +315,7 @@ DataReductionProxyRequestType GetDataReductionProxyRequestType(
   }
 #endif
   if (request->response_info().headers &&
-      HasDataReductionProxyViaHeader(request->response_info().headers, NULL)) {
+      HasDataReductionProxyViaHeader(request->response_info().headers)) {
     return VIA_DATA_REDUCTION_PROXY;
   }
   return UNKNOWN_TYPE;

components/data_reduction_proxy/common/data_reduction_proxy_headers.cc

@@ -21,18 +21,6 @@ using net::ProxyService;
 
 namespace {
 
-const char kChromeProxyHeader[] = "chrome-proxy";
-const char kActionValueDelimiter = '=';
-
-const char kChromeProxyActionBlock[] = "block";
-const char kChromeProxyActionBypass[] = "bypass";
-
-// Actions for tamper detection fingerprints.
-const char kChromeProxyActionFingerprintChromeProxy[]   = "fcp";
-const char kChromeProxyActionFingerprintVia[]           = "fvia";
-const char kChromeProxyActionFingerprintOtherHeaders[]  = "foh";
-const char kChromeProxyActionFingerprintContentLength[] = "fcl";
-
 const int kShortBypassMaxSeconds = 59;
 const int kMediumBypassMaxSeconds = 300;
 
@@ -47,51 +35,21 @@ base::TimeDelta GetDefaultBypassDuration() {
 
 namespace data_reduction_proxy {
 
-bool GetDataReductionProxyActionValue(
-    const net::HttpResponseHeaders* headers,
-    const std::string& action_prefix,
-    std::string* action_value) {
-  DCHECK(headers);
-  DCHECK(!action_prefix.empty());
-  // A valid action does not include a trailing '='.
-  DCHECK(action_prefix[action_prefix.size() - 1] != kActionValueDelimiter);
-  void* iter = NULL;
-  std::string value;
-  std::string prefix = action_prefix + kActionValueDelimiter;
-
-  while (headers->EnumerateHeader(&iter, kChromeProxyHeader, &value)) {
-    if (value.size() > prefix.size()) {
-      if (LowerCaseEqualsASCII(value.begin(),
-                               value.begin() + prefix.size(),
-                               prefix.c_str())) {
-        if (action_value)
-          *action_value = value.substr(prefix.size());
-        return true;
-      }
-    }
-  }
-  return false;
-}
-
 bool ParseHeadersAndSetBypassDuration(const net::HttpResponseHeaders* headers,
                                       const std::string& action_prefix,
                                       base::TimeDelta* bypass_duration) {
-  DCHECK(headers);
-  DCHECK(!action_prefix.empty());
-  // A valid action does not include a trailing '='.
-  DCHECK(action_prefix[action_prefix.size() - 1] != kActionValueDelimiter);
   void* iter = NULL;
   std::string value;
-  std::string prefix = action_prefix + kActionValueDelimiter;
+  std::string name = "chrome-proxy";
 
-  while (headers->EnumerateHeader(&iter, kChromeProxyHeader, &value)) {
-    if (value.size() > prefix.size()) {
+  while (headers->EnumerateHeader(&iter, name, &value)) {
+    if (value.size() > action_prefix.size()) {
       if (LowerCaseEqualsASCII(value.begin(),
-                               value.begin() + prefix.size(),
-                               prefix.c_str())) {
+                               value.begin() + action_prefix.size(),
+                               action_prefix.c_str())) {
         int64 seconds;
         if (!base::StringToInt64(
-                StringPiece(value.begin() + prefix.size(), value.end()),
+                StringPiece(value.begin() + action_prefix.size(), value.end()),
                 &seconds) || seconds < 0) {
           continue;  // In case there is a well formed instruction.
         }
@@ -124,21 +82,20 @@ bool ParseHeadersAndSetProxyInfo(const net::HttpResponseHeaders* headers,
   // 'block' takes precedence over 'bypass', so look for it first.
   // TODO(bengr): Reduce checks for 'block' and 'bypass' to a single loop.
   if (ParseHeadersAndSetBypassDuration(
-          headers, kChromeProxyActionBlock, &proxy_info->bypass_duration)) {
+          headers, "block=", &proxy_info->bypass_duration)) {
     proxy_info->bypass_all = true;
     return true;
   }
 
   // Next, look for 'bypass'.
   if (ParseHeadersAndSetBypassDuration(
-          headers, kChromeProxyActionBypass, &proxy_info->bypass_duration)) {
+          headers, "bypass=", &proxy_info->bypass_duration)) {
     return true;
   }
   return false;
 }
 
-bool HasDataReductionProxyViaHeader(const net::HttpResponseHeaders* headers,
-                                    bool* has_intermediary) {
+bool HasDataReductionProxyViaHeader(const net::HttpResponseHeaders* headers) {
   const size_t kVersionSize = 4;
   const char kDataReductionProxyViaValue[] = "Chrome-Compression-Proxy";
   size_t value_len = strlen(kDataReductionProxyViaValue);
@@ -150,13 +107,8 @@ bool HasDataReductionProxyViaHeader(const net::HttpResponseHeaders* headers,
   // 'Via: 1.1 Chrome-Compression-Proxy'
   while (headers->EnumerateHeader(&iter, "via", &value)) {
     if (value.size() >= kVersionSize + value_len &&
-        !value.compare(kVersionSize, value_len, kDataReductionProxyViaValue)) {
-      if (has_intermediary)
-        // We assume intermediary exists if there is another Via header after
-        // the data reduction proxy's Via header.
-        *has_intermediary = !(headers->EnumerateHeader(&iter, "via", &value));
+        !value.compare(kVersionSize, value_len, kDataReductionProxyViaValue))
       return true;
-    }
   }
 
   // TODO(bengr): Remove deprecated header value.
@@ -164,11 +116,8 @@ bool HasDataReductionProxyViaHeader(const net::HttpResponseHeaders* headers,
       "1.1 Chrome Compression Proxy";
   iter = NULL;
   while (headers->EnumerateHeader(&iter, "via", &value))
-    if (value == kDeprecatedDataReductionProxyViaValue) {
-      if (has_intermediary)
-        *has_intermediary = !(headers->EnumerateHeader(&iter, "via", &value));
+    if (value == kDeprecatedDataReductionProxyViaValue)
       return true;
-    }
 
   return false;
 }
@@ -202,7 +151,7 @@ GetDataReductionProxyBypassType(
       !headers->HasHeader("Proxy-Authenticate")) {
     return ProxyService::MALFORMED_407;
   }
-  if (!HasDataReductionProxyViaHeader(headers, NULL) &&
+  if (!HasDataReductionProxyViaHeader(headers) &&
       (headers->response_code() != net::HTTP_NOT_MODIFIED)) {
     // A Via header might not be present in a 304. Since the goal of a 304
     // response is to minimize information transfer, a sender in general
@@ -221,59 +170,4 @@ GetDataReductionProxyBypassType(
   return ProxyService::BYPASS_EVENT_TYPE_MAX;
 }
 
-bool GetDataReductionProxyActionFingerprintChromeProxy(
-    const net::HttpResponseHeaders* headers,
-    std::string* chrome_proxy_fingerprint) {
-  return GetDataReductionProxyActionValue(
-      headers,
-      kChromeProxyActionFingerprintChromeProxy,
-      chrome_proxy_fingerprint);
-}
-
-bool GetDataReductionProxyActionFingerprintVia(
-    const net::HttpResponseHeaders* headers,
-    std::string* via_fingerprint) {
-  return GetDataReductionProxyActionValue(
-      headers,
-      kChromeProxyActionFingerprintVia,
-      via_fingerprint);
-}
-
-bool GetDataReductionProxyActionFingerprintOtherHeaders(
-    const net::HttpResponseHeaders* headers,
-    std::string* other_headers_fingerprint) {
-  return GetDataReductionProxyActionValue(
-      headers,
-      kChromeProxyActionFingerprintOtherHeaders,
-      other_headers_fingerprint);
-}
-
-bool GetDataReductionProxyActionFingerprintContentLength(
-    const net::HttpResponseHeaders* headers,
-    std::string* content_length_fingerprint) {
-  return GetDataReductionProxyActionValue(
-      headers,
-      kChromeProxyActionFingerprintContentLength,
-      content_length_fingerprint);
-}
-
-void GetDataReductionProxyHeaderWithFingerprintRemoved(
-    const net::HttpResponseHeaders* headers,
-    std::vector<std::string>* values) {
-  DCHECK(values);
-  std::string chrome_proxy_fingerprint_prefix = std::string(
-      kChromeProxyActionFingerprintChromeProxy) + kActionValueDelimiter;
-
-  std::string value;
-  void* iter = NULL;
-  while (headers->EnumerateHeader(&iter, kChromeProxyHeader, &value)) {
-    if (!LowerCaseEqualsASCII(
-        value.begin(),
-        value.begin() + chrome_proxy_fingerprint_prefix.size(),
-        chrome_proxy_fingerprint_prefix.c_str())) {
-      values->push_back(value);
-    }
-  }
-}
-
 }  // namespace data_reduction_proxy

components/data_reduction_proxy/common/data_reduction_proxy_headers.h

@@ -41,12 +41,8 @@ bool ParseHeadersAndSetProxyInfo(const net::HttpResponseHeaders* headers,
                                  DataReductionProxyInfo* proxy_info);
 
 // Returns true if the response contains the data reduction proxy Via header
-// value. If non-NULL, sets |has_intermediary| to true if another server added
-// a Via header after the data reduction proxy, and to false otherwise. Used to
-// check the integrity of data reduction proxy responses and whether there are
-// other middleboxes between the data reduction proxy and the client.
-bool HasDataReductionProxyViaHeader(const net::HttpResponseHeaders* headers,
-                                    bool* has_intermediary);
+// value. Used to check the integrity of data reduction proxy responses.
+bool HasDataReductionProxyViaHeader(const net::HttpResponseHeaders* headers);
 
 // Returns the reason why the Chrome proxy should be bypassed or not, and
 // populates |proxy_info| with information on how long to bypass if
@@ -55,44 +51,11 @@ net::ProxyService::DataReductionProxyBypassType GetDataReductionProxyBypassType(
     const net::HttpResponseHeaders* headers,
     DataReductionProxyInfo* proxy_info);
 
-// Searches for the specified Chrome-Proxy action, and if present saves its
-// value as a string in |action_value|. Only returns the first one and ignores
-// the rest if multiple actions match |action_prefix|.
-bool GetDataReductionProxyActionValue(
-    const net::HttpResponseHeaders* headers,
-    const std::string& action_prefix,
-    std::string* action_value);
-
 // Searches for the specified Chrome-Proxy action, and if present interprets
 // its value as a duration in seconds.
 bool ParseHeadersAndSetBypassDuration(const net::HttpResponseHeaders* headers,
                                       const std::string& action_prefix,
                                       base::TimeDelta* bypass_duration);
 
-// Gets the fingerprint of the Chrome-Proxy header.
-bool GetDataReductionProxyActionFingerprintChromeProxy(
-    const net::HttpResponseHeaders* headers,
-    std::string* chrome_proxy_fingerprint);
-
-// Gets the fingerprint of the Via header.
-bool GetDataReductionProxyActionFingerprintVia(
-    const net::HttpResponseHeaders* headers,
-    std::string* via_fingerprint);
-
-// Gets the fingerprint of a list of headers.
-bool GetDataReductionProxyActionFingerprintOtherHeaders(
-    const net::HttpResponseHeaders* headers,
-    std::string* other_headers_fingerprint);
-
-// Gets the fingerprint of Content-Length header.
-bool GetDataReductionProxyActionFingerprintContentLength(
-    const net::HttpResponseHeaders* headers,
-    std::string* content_length_fingerprint);
-
-// Returns values of the Chrome-Proxy header, but with its fingerprint removed.
-void GetDataReductionProxyHeaderWithFingerprintRemoved(
-    const net::HttpResponseHeaders* headers,
-    std::vector<std::string>* values);
-
 }  // namespace data_reduction_proxy
 #endif  // COMPONENTS_DATA_REDUCTION_PROXY_COMMON_DATA_REDUCTION_PROXY_HEADERS_H_