netwerk/protocol/http/AlternateServices.h
author Nicholas Hurley <hurley@mozilla.com>
Mon, 15 Oct 2018 21:52:04 +0000
changeset 497100 32e5d5e6c9804247b0f82f931dc875fdc838f750
parent 473776 c2270d35829d183bcd506394228f21f4113992ae
child 505141 04f0bbf40bf36957dc1f72a8aae9916df0e3222f
permissions -rw-r--r--
Bug 1493724 - Don't overwrite still-valid altsvc mappings until a new one is validated. r=valentin Right now, as soon as we receive an alt-svc header or frame for an origin, we will overwrite any mapping we already have for that origin, even if it's still valid. This means that, should validation fail for the new mapping, we will have blown away a perfectly usable alt-svc mapping for no good reason. This patch prevents us from overwriting until we know the new mapping is good. Differential Revision: https://phabricator.services.mozilla.com/D8747

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set sw=2 ts=8 et tw=80 : */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

/*
Alt-Svc allows separation of transport routing from the origin host without
using a proxy. See https://httpwg.github.io/http-extensions/alt-svc.html and
https://tools.ietf.org/html/draft-ietf-httpbis-alt-svc-06

 Nice To Have Future Enhancements::
 * flush on network change event when we have an indicator
 * use established https channel for http instead separate of conninfo hash
 * pin via http-tls header
 * clear based on origin when a random fail happens not just 421
 * upon establishment of channel, cancel and retry trans that have not yet written anything
 * persistent storage (including private browsing filter)
 * memory reporter for cache, but this is rather tiny
*/

#ifndef mozilla_net_AlternateServices_h
#define mozilla_net_AlternateServices_h

#include "mozilla/DataStorage.h"
#include "nsRefPtrHashtable.h"
#include "nsString.h"
#include "nsIInterfaceRequestor.h"
#include "nsIStreamListener.h"
#include "nsISpeculativeConnect.h"
#include "mozilla/BasePrincipal.h"

class nsILoadInfo;

namespace mozilla { namespace net {

class nsProxyInfo;
class nsHttpConnectionInfo;
class nsHttpTransaction;
class nsHttpChannel;
class WellKnownChecker;

class AltSvcMapping
{
  NS_INLINE_DECL_THREADSAFE_REFCOUNTING(AltSvcMapping)

private: // ctor from ProcessHeader
  AltSvcMapping(DataStorage *storage,
                int32_t storageEpoch,
                const nsACString &originScheme,
                const nsACString &originHost,
                int32_t originPort,
                const nsACString &username,
                bool privateBrowsing,
                uint32_t expiresAt,
                const nsACString &alternateHost,
                int32_t alternatePort,
                const nsACString &npnToken,
                const OriginAttributes &originAttributes);
public:
  AltSvcMapping(DataStorage *storage, int32_t storageEpoch, const nsCString &serialized);

  static void ProcessHeader(const nsCString &buf, const nsCString &originScheme,
                            const nsCString &originHost, int32_t originPort,
                            const nsACString &username, bool privateBrowsing,
                            nsIInterfaceRequestor *callbacks, nsProxyInfo *proxyInfo,
                            uint32_t caps, const OriginAttributes &originAttributes);

  // AcceptableProxy() decides whether a particular proxy configuration (pi) is suitable
  // for use with Alt-Svc. No proxy (including a null pi) is suitable.
  static bool AcceptableProxy(nsProxyInfo *pi);

  const nsCString &AlternateHost() const { return mAlternateHost; }
  const nsCString &OriginHost() const { return mOriginHost; }
  uint32_t OriginPort() const { return mOriginPort; }
  const nsCString &HashKey() const { return mHashKey; }
  uint32_t AlternatePort() const { return mAlternatePort; }
  bool Validated() { return mValidated; }
  int32_t GetExpiresAt() { return mExpiresAt; }
  bool RouteEquals(AltSvcMapping *map);
  bool HTTPS() { return mHttps; }

  void GetConnectionInfo(nsHttpConnectionInfo **outCI, nsProxyInfo *pi,
                         const OriginAttributes &originAttributes);

  int32_t TTL();
  int32_t StorageEpoch() { return mStorageEpoch; }
  bool    Private() { return mPrivate; }

  void SetValidated(bool val);
  void SetMixedScheme(bool val);
  void SetExpiresAt(int32_t val);
  void SetExpired();
  void Sync();
  void SetSyncOnlyOnSuccess(bool aSOOS) { mSyncOnlyOnSuccess = aSOOS; }

  static void MakeHashKey(nsCString &outKey,
                          const nsACString &originScheme,
                          const nsACString &originHost,
                          int32_t originPort,
                          bool privateBrowsing,
                          const OriginAttributes &originAttributes);

private:
  virtual ~AltSvcMapping() = default;
  void     SyncString(const nsCString& val);
  RefPtr<DataStorage> mStorage;
  int32_t             mStorageEpoch;
  void Serialize (nsCString &out);

  nsCString mHashKey;

  // If you change any of these members, update Serialize()
  nsCString mAlternateHost;
  MOZ_INIT_OUTSIDE_CTOR int32_t mAlternatePort;

  nsCString mOriginHost;
  MOZ_INIT_OUTSIDE_CTOR int32_t mOriginPort;

  nsCString mUsername;
  MOZ_INIT_OUTSIDE_CTOR bool mPrivate;

  MOZ_INIT_OUTSIDE_CTOR uint32_t mExpiresAt; // alt-svc mappping

  MOZ_INIT_OUTSIDE_CTOR bool mValidated;
  MOZ_INIT_OUTSIDE_CTOR bool mHttps; // origin is https://
  MOZ_INIT_OUTSIDE_CTOR bool mMixedScheme; // .wk allows http and https on same con

  nsCString mNPNToken;

  OriginAttributes mOriginAttributes;

  bool mSyncOnlyOnSuccess;
};

class AltSvcOverride : public nsIInterfaceRequestor
                     , public nsISpeculativeConnectionOverrider
{
public:
  NS_DECL_THREADSAFE_ISUPPORTS
  NS_DECL_NSISPECULATIVECONNECTIONOVERRIDER
  NS_DECL_NSIINTERFACEREQUESTOR

  explicit AltSvcOverride(nsIInterfaceRequestor *aRequestor)
    : mCallbacks(aRequestor) {}

private:
  virtual ~AltSvcOverride() = default;
  nsCOMPtr<nsIInterfaceRequestor> mCallbacks;
};

class TransactionObserver final : public nsIStreamListener
{
public:
  NS_DECL_THREADSAFE_ISUPPORTS
  NS_DECL_NSISTREAMLISTENER
  NS_DECL_NSIREQUESTOBSERVER

  TransactionObserver(nsHttpChannel *channel, WellKnownChecker *checker);
  void Complete(nsHttpTransaction *, nsresult);
private:
  friend class WellKnownChecker;
  virtual ~TransactionObserver() = default;

  nsCOMPtr<nsISupports> mChannelRef;
  nsHttpChannel        *mChannel;
  WellKnownChecker     *mChecker;
  nsCString             mWKResponse;

  bool mRanOnce;
  bool mAuthOK; // confirmed no TLS failure
  bool mVersionOK; // connection h2
  bool mStatusOK; // HTTP Status 200
};

class AltSvcCache
{
public:
  AltSvcCache() : mStorageEpoch(0) {}
  virtual ~AltSvcCache () = default;
  void UpdateAltServiceMapping(AltSvcMapping *map, nsProxyInfo *pi,
                               nsIInterfaceRequestor *, uint32_t caps,
                               const OriginAttributes &originAttributes); // main thread
  already_AddRefed<AltSvcMapping> GetAltServiceMapping(const nsACString &scheme,
                                                       const nsACString &host,
                                                       int32_t port, bool pb,
                                                       const OriginAttributes &originAttributes);
  void ClearAltServiceMappings();
  void ClearHostMapping(const nsACString &host, int32_t port, const OriginAttributes &originAttributes);
  void ClearHostMapping(nsHttpConnectionInfo *ci);
  DataStorage *GetStoragePtr() { return mStorage.get(); }
  int32_t      StorageEpoch()  { return mStorageEpoch; }

private:
  already_AddRefed<AltSvcMapping> LookupMapping(const nsCString &key, bool privateBrowsing);
  RefPtr<DataStorage>             mStorage;
  int32_t                         mStorageEpoch;
};

} // namespace net
} // namespace mozilla

#endif // include guard