Add read-only access to POST data for webRequest's onBeforeRequest

chrome/browser/extensions/api/web_request/web_request_api.cc

Index: chrome/browser/extensions/api/web_request/web_request_api.cc
diff --git a/chrome/browser/extensions/api/web_request/web_request_api.cc b/chrome/browser/extensions/api/web_request/web_request_api.cc
index 2019494bf36a5895d66edded30aa55dcd85545d1..e75f20dca271be69aef1dbe2dbaefae0469b8e35 100644
--- a/chrome/browser/extensions/api/web_request/web_request_api.cc
+++ b/chrome/browser/extensions/api/web_request/web_request_api.cc
@@ -19,6 +19,7 @@
 #include "chrome/browser/extensions/api/declarative_webrequest/webrequest_rule.h"
 #include "chrome/browser/extensions/api/declarative_webrequest/webrequest_rules_registry.h"
 #include "chrome/browser/extensions/api/web_navigation/web_navigation_api_helpers.h"
+#include "chrome/browser/extensions/api/web_request/post_data_parser.h"
 #include "chrome/browser/extensions/api/web_request/web_request_api_constants.h"
 #include "chrome/browser/extensions/api/web_request/web_request_api_helpers.h"
 #include "chrome/browser/extensions/api/web_request/web_request_time_tracker.h"
@@ -45,6 +46,7 @@
 #include "grit/generated_resources.h"
 #include "net/base/auth.h"
 #include "net/base/net_errors.h"
+#include "net/base/upload_data.h"
 #include "net/http/http_response_headers.h"
 #include "net/url_request/url_request.h"
 #include "ui/base/l10n/l10n_util.h"
@@ -76,6 +78,15 @@ static const char* const kWebRequestEvents[] = {
 
 #define ARRAYEND(array) (array + arraysize(array))
 
+// Returns the frame ID as it will be passed to the extension:
+// 0 if the navigation happens in the main frame, or the frame ID
+// modulo 32 bits otherwise.
+// Keep this in sync with the GetFrameId() function in
+// extension_webnavigation_api.cc.
+int GetFrameId(bool is_main_frame, int64 frame_id) {
+  return is_main_frame ? 0 : static_cast<int>(frame_id);
+}
+
 bool IsWebRequestEvent(const std::string& event_name) {
   return std::find(kWebRequestEvents, ARRAYEND(kWebRequestEvents),
                    event_name) != ARRAYEND(kWebRequestEvents);
@@ -156,6 +167,54 @@ void ExtractRequestInfo(net::URLRequest* request, DictionaryValue* out) {
   out->SetDouble(keys::kTimeStampKey, base::Time::Now().ToDoubleT() * 1000);
 }
 
+// Takes |dictionary| of <string, list of strings> pairs, and gets the list
+// for |key|, creating it if necessary.
+ListValue* GetOrCreateList(DictionaryValue* dictionary,
+                           const std::string& key) {
+  ListValue* list = NULL;
+  if (!dictionary->GetList(key, &list)) {
+    list = new ListValue();
+    dictionary->Set(key, list);
+  }
+  return list;
+}
+
+// Extracts the POST data from |request| and writes the data into |out|.
+// This can be expensive, so it's separated from ExtractRequestInfo().
+// Contract: request->method() == "POST"
+void ExtractRequestInfoPost(net::URLRequest* request, DictionaryValue* out) {
+  const std::vector<net::UploadData::Element>* elements =
+      request->get_upload()->elements();
+  scoped_ptr<extensions::PostDataParser> parser =
+      extensions::PostDataParser::CreatePostDataParser(request);
+  if (parser.get() == NULL) {
+    // No parser means most probably unsupported form encoding.
+    return;
+  }
+  scoped_ptr<DictionaryValue> post_data(new DictionaryValue());
+  scoped_ptr<DictionaryValue> form_data(new DictionaryValue());
+  std::vector<net::UploadData::Element>::const_iterator element;
+  bool data_valid = true;
+  for (element = elements->begin();
+       data_valid && element != elements->end(); ++element) {
+    if (element->type() != net::UploadData::TYPE_BYTES) {
+      // We do not handle data including blobs or chunks.
+      if (element->type() != net::UploadData::TYPE_FILE)
+        data_valid = false;
+      continue;
+    }
+    if (!parser->SetSource(&(element->bytes()))) continue;
+    extensions::PostDataParser::Result result;
+    while (parser->GetNextPair(&result)) {
+      GetOrCreateList(form_data.get(), result.get_key())->Append(
+          new StringValue(result.get_val()));
+    }
+  }
+  if (data_valid && parser->AllDataReadOK())
+    post_data->Set(keys::kFormDataKey, form_data.release());
+  out->Set(keys::kPostDataKey, post_data.release());
+}
+
 // Converts a HttpHeaders dictionary to a |name|, |value| pair. Returns
 // true if successful.
 bool FromHeaderDictionary(const DictionaryValue* header_value,
@@ -408,6 +467,8 @@ bool ExtensionWebRequestEventRouter::ExtraInfoSpec::InitFromValue(
       *extra_info_spec |= BLOCKING;
     else if (str == "asyncBlocking")
       *extra_info_spec |= ASYNC_BLOCKING;
+    else if (str == "requestPostData")
+      *extra_info_spec |= REQUEST_POST_DATA;
     else
       return false;
 
@@ -493,6 +554,9 @@ int ExtensionWebRequestEventRouter::OnBeforeRequest(
     ListValue args;
     DictionaryValue* dict = new DictionaryValue();
     ExtractRequestInfo(request, dict);
+    if (extra_info_spec & ExtraInfoSpec::REQUEST_POST_DATA &&
+        request->method() == "POST")
+      ExtractRequestInfoPost(request, dict);
     args.Append(dict);
 
     initialize_blocked_requests |=