Home | History | Annotate | Download | only in dns 
      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 #include "extensions/browser/api/dns/dns_api.h"
      6 
      7 #include "base/bind.h"
      8 #include "base/values.h"
      9 #include "content/public/browser/browser_context.h"
     10 #include "content/public/browser/browser_thread.h"
     11 #include "content/public/browser/resource_context.h"
     12 #include "extensions/browser/api/dns/host_resolver_wrapper.h"
     13 #include "extensions/common/api/dns.h"
     14 #include "net/base/host_port_pair.h"
     15 #include "net/base/net_errors.h"
     16 #include "net/base/net_log.h"
     17 
     18 using content::BrowserThread;
     19 using extensions::core_api::dns::ResolveCallbackResolveInfo;
     20 
     21 namespace Resolve = extensions::core_api::dns::Resolve;
     22 
     23 namespace extensions {
     24 
     25 DnsResolveFunction::DnsResolveFunction()
     26     : resource_context_(NULL),
     27       response_(false),
     28       request_handle_(new net::HostResolver::RequestHandle()),
     29       addresses_(new net::AddressList) {}
     30 
     31 DnsResolveFunction::~DnsResolveFunction() {}
     32 
     33 bool DnsResolveFunction::RunAsync() {
     34   scoped_ptr<Resolve::Params> params(Resolve::Params::Create(*args_));
     35   EXTENSION_FUNCTION_VALIDATE(params.get());
     36 
     37   hostname_ = params->hostname;
     38   resource_context_ = browser_context()->GetResourceContext();
     39 
     40   bool result = BrowserThread::PostTask(
     41       BrowserThread::IO,
     42       FROM_HERE,
     43       base::Bind(&DnsResolveFunction::WorkOnIOThread, this));
     44   DCHECK(result);
     45   return true;
     46 }
     47 
     48 void DnsResolveFunction::WorkOnIOThread() {
     49   DCHECK_CURRENTLY_ON(BrowserThread::IO);
     50 
     51   net::HostResolver* host_resolver =
     52       HostResolverWrapper::GetInstance()->GetHostResolver(resource_context_);
     53   DCHECK(host_resolver);
     54 
     55   // Yes, we are passing zero as the port. There are some interesting but not
     56   // presently relevant reasons why HostResolver asks for the port of the
     57   // hostname you'd like to resolve, even though it doesn't use that value in
     58   // determining its answer.
     59   net::HostPortPair host_port_pair(hostname_, 0);
     60 
     61   net::HostResolver::RequestInfo request_info(host_port_pair);
     62   int resolve_result = host_resolver->Resolve(
     63       request_info,
     64       net::DEFAULT_PRIORITY,
     65       addresses_.get(),
     66       base::Bind(&DnsResolveFunction::OnLookupFinished, this),
     67       request_handle_.get(),
     68       net::BoundNetLog());
     69 
     70   // Balanced in OnLookupFinished.
     71   AddRef();
     72 
     73   if (resolve_result != net::ERR_IO_PENDING)
     74     OnLookupFinished(resolve_result);
     75 }
     76 
     77 void DnsResolveFunction::RespondOnUIThread() {
     78   DCHECK_CURRENTLY_ON(BrowserThread::UI);
     79   SendResponse(response_);
     80 }
     81 
     82 void DnsResolveFunction::OnLookupFinished(int resolve_result) {
     83   scoped_ptr<ResolveCallbackResolveInfo> resolve_info(
     84       new ResolveCallbackResolveInfo());
     85   resolve_info->result_code = resolve_result;
     86   if (resolve_result == net::OK) {
     87     DCHECK(!addresses_->empty());
     88     resolve_info->address.reset(
     89         new std::string(addresses_->front().ToStringWithoutPort()));
     90   }
     91   results_ = Resolve::Results::Create(*resolve_info);
     92   response_ = true;
     93 
     94   bool post_task_result = BrowserThread::PostTask(
     95       BrowserThread::UI,
     96       FROM_HERE,
     97       base::Bind(&DnsResolveFunction::RespondOnUIThread, this));
     98   DCHECK(post_task_result);
     99 
    100   Release();  // Added in WorkOnIOThread().
    101 }
    102 
    103 }  // namespace extensions
    104