/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* 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/. */

#ifndef nsCookieService_h__
#define nsCookieService_h__

#include "nsICookieService.h"
#include "nsICookieManager.h"
#include "nsIObserver.h"
#include "nsWeakReference.h"

#include "nsCookie.h"
#include "nsCookieKey.h"
#include "nsString.h"
#include "nsAutoPtr.h"
#include "nsHashKeys.h"
#include "nsIMemoryReporter.h"
#include "nsTHashtable.h"
#include "mozIStorageStatement.h"
#include "mozIStorageAsyncStatement.h"
#include "mozIStoragePendingStatement.h"
#include "mozIStorageConnection.h"
#include "mozIStorageRow.h"
#include "mozIStorageCompletionCallback.h"
#include "mozIStorageStatementCallback.h"
#include "mozIStorageFunction.h"
#include "nsIVariant.h"
#include "nsIFile.h"
#include "mozilla/Atomics.h"
#include "mozilla/BasePrincipal.h"
#include "mozilla/MemoryReporting.h"
#include "mozilla/Maybe.h"
#include "mozilla/Monitor.h"
#include "mozilla/UniquePtr.h"

using mozilla::OriginAttributes;

class nsICookiePermission;
class nsIEffectiveTLDService;
class nsIIDNService;
class nsIPrefBranch;
class nsIObserverService;
class nsIURI;
class nsIChannel;
class nsIArray;
class nsIThread;
class mozIStorageService;
class mozIThirdPartyUtil;
class ReadCookieDBListener;

struct nsListIter;

namespace mozilla {
namespace net {
class nsCookieKey;
class CookieServiceParent;
}  // namespace net
}  // namespace mozilla

using mozilla::net::nsCookieKey;
// Inherit from nsCookieKey so this can be stored in nsTHashTable
// TODO: why aren't we using nsClassHashTable<nsCookieKey, ArrayType>?
class nsCookieEntry : public nsCookieKey {
 public:
  // Hash methods
  typedef nsTArray<RefPtr<nsCookie> > ArrayType;
  typedef ArrayType::index_type IndexType;

  explicit nsCookieEntry(KeyTypePointer aKey) : nsCookieKey(aKey) {}

  nsCookieEntry(const nsCookieEntry &toCopy) {
    // if we end up here, things will break. nsTHashtable shouldn't
    // allow this, since we set ALLOW_MEMMOVE to true.
    MOZ_ASSERT_UNREACHABLE("nsCookieEntry copy constructor is forbidden!");
  }

  ~nsCookieEntry() = default;

  inline ArrayType &GetCookies() { return mCookies; }

  size_t SizeOfExcludingThis(mozilla::MallocSizeOf aMallocSizeOf) const;

 private:
  ArrayType mCookies;
};

// struct for a constant cookie for threadsafe
struct ConstCookie {
  ConstCookie(const nsCString &aName, const nsCString &aValue,
              const nsCString &aHost, const nsCString &aPath, int64_t aExpiry,
              int64_t aLastAccessed, int64_t aCreationTime, bool aIsSecure,
              bool aIsHttpOnly, const OriginAttributes &aOriginAttributes,
              int32_t aSameSite)
      : name(aName),
        value(aValue),
        host(aHost),
        path(aPath),
        expiry(aExpiry),
        lastAccessed(aLastAccessed),
        creationTime(aCreationTime),
        isSecure(aIsSecure),
        isHttpOnly(aIsHttpOnly),
        originAttributes(aOriginAttributes),
        sameSite(aSameSite) {}

  const nsCString name;
  const nsCString value;
  const nsCString host;
  const nsCString path;
  const int64_t expiry;
  const int64_t lastAccessed;
  const int64_t creationTime;
  const bool isSecure;
  const bool isHttpOnly;
  const OriginAttributes originAttributes;
  const int32_t sameSite;
};

// encapsulates a (key, nsCookie) tuple for temporary storage purposes.
struct CookieDomainTuple {
  nsCookieKey key;
  mozilla::UniquePtr<ConstCookie> cookie;
};

// encapsulates in-memory and on-disk DB states, so we can
// conveniently switch state when entering or exiting private browsing.
struct DBState final {
  DBState()
      : cookieCount(0),
        cookieOldestTime(INT64_MAX),
        corruptFlag(OK),
        readListener(nullptr) {}

 private:
  // Private destructor, to discourage deletion outside of Release():
  ~DBState() = default;

 public:
  NS_INLINE_DECL_REFCOUNTING(DBState)

  size_t SizeOfIncludingThis(mozilla::MallocSizeOf aMallocSizeOf) const;

  // State of the database connection.
  enum CorruptFlag {
    OK,                   // normal
    CLOSING_FOR_REBUILD,  // corruption detected, connection closing
    REBUILDING            // close complete, rebuilding database from memory
  };

  nsTHashtable<nsCookieEntry> hostTable;
  uint32_t cookieCount;
  int64_t cookieOldestTime;
  nsCOMPtr<nsIFile> cookieFile;
  nsCOMPtr<mozIStorageConnection> dbConn;
  nsCOMPtr<mozIStorageAsyncStatement> stmtInsert;
  nsCOMPtr<mozIStorageAsyncStatement> stmtDelete;
  nsCOMPtr<mozIStorageAsyncStatement> stmtUpdate;
  CorruptFlag corruptFlag;

  // Various parts representing asynchronous read state. These are useful
  // while the background read is taking place.
  nsCOMPtr<mozIStorageConnection> syncConn;
  nsCOMPtr<mozIStorageStatement> stmtReadDomain;
  // The asynchronous read listener. This is a weak ref (storage has ownership)
  // since it may need to outlive the DBState's database connection.
  ReadCookieDBListener *readListener;

  // DB completion handlers.
  nsCOMPtr<mozIStorageStatementCallback> insertListener;
  nsCOMPtr<mozIStorageStatementCallback> updateListener;
  nsCOMPtr<mozIStorageStatementCallback> removeListener;
  nsCOMPtr<mozIStorageCompletionCallback> closeListener;
};

// these constants represent a decision about a cookie based on user prefs.
enum CookieStatus {
  STATUS_ACCEPTED,
  STATUS_ACCEPT_SESSION,
  STATUS_REJECTED,
  // STATUS_REJECTED_WITH_ERROR indicates the cookie should be rejected because
  // of an error (rather than something the user can control). this is used for
  // notification purposes, since we only want to notify of rejections where
  // the user can do something about it (e.g. whitelist the site).
  STATUS_REJECTED_WITH_ERROR
};

// Result codes for TryInitDB() and Read().
enum OpenDBResult { RESULT_OK, RESULT_RETRY, RESULT_FAILURE };

/******************************************************************************
 * nsCookieService:
 * class declaration
 ******************************************************************************/

// struct for temporarily storing cookie attributes during header parsing
struct nsCookieAttributes {
  nsAutoCString name;
  nsAutoCString value;
  nsAutoCString host;
  nsAutoCString path;
  nsAutoCString expires;
  nsAutoCString maxage;
  int64_t expiryTime;
  bool isSession;
  bool isSecure;
  bool isHttpOnly;
  int8_t sameSite;
};

class nsCookieService final : public nsICookieService,
                              public nsICookieManager,
                              public nsIObserver,
                              public nsSupportsWeakReference,
                              public nsIMemoryReporter {
 private:
  size_t SizeOfIncludingThis(mozilla::MallocSizeOf aMallocSizeOf) const;

  static bool sSameSiteEnabled;  // cached pref

 public:
  NS_DECL_ISUPPORTS
  NS_DECL_NSIOBSERVER
  NS_DECL_NSICOOKIESERVICE
  NS_DECL_NSICOOKIEMANAGER
  NS_DECL_NSIMEMORYREPORTER

  nsCookieService();
  static already_AddRefed<nsICookieService> GetXPCOMSingleton();
  nsresult Init();

  /**
   * Start watching the observer service for messages indicating that an app has
   * been uninstalled.  When an app is uninstalled, we get the cookie service
   * (thus instantiating it, if necessary) and clear all the cookies for that
   * app.
   */
  static void AppClearDataObserverInit();
  static nsAutoCString GetPathFromURI(nsIURI *aHostURI);
  static nsresult GetBaseDomain(nsIEffectiveTLDService *aTLDService,
                                nsIURI *aHostURI, nsCString &aBaseDomain,
                                bool &aRequireHostMatch);
  static nsresult GetBaseDomainFromHost(nsIEffectiveTLDService *aTLDService,
                                        const nsACString &aHost,
                                        nsCString &aBaseDomain);
  static bool DomainMatches(nsCookie *aCookie, const nsACString &aHost);
  static bool IsSameSiteEnabled();
  static bool PathMatches(nsCookie *aCookie, const nsACString &aPath);
  static bool CanSetCookie(nsIURI *aHostURI, const nsCookieKey &aKey,
                           nsCookieAttributes &aCookieAttributes,
                           bool aRequireHostMatch, CookieStatus aStatus,
                           nsDependentCString &aCookieHeader,
                           int64_t aServerTime, bool aFromHttp,
                           nsIChannel *aChannel, bool aLeaveSercureAlone,
                           bool &aSetCookie,
                           mozIThirdPartyUtil *aThirdPartyUtil);
  static CookieStatus CheckPrefs(
      nsICookiePermission *aPermissionServices, uint8_t aCookieBehavior,
      bool aThirdPartySession, bool aThirdPartyNonsecureSession,
      nsIURI *aHostURI, bool aIsForeign, bool aIsTrackingResource,
      bool aIsFirstPartyStorageAccessGranted, const char *aCookieHeader,
      const int aNumOfCookies, const OriginAttributes &aOriginAttrs,
      uint32_t *aRejectedReason);
  static int64_t ParseServerTime(const nsCString &aServerTime);
  void GetCookiesForURI(nsIURI *aHostURI, bool aIsForeign,
                        bool aIsTrackingResource,
                        bool aFirstPartyStorageAccessGranted,
                        bool aIsSafeTopLevelNav, bool aIsTopLevelForeign,
                        bool aHttpBound, const OriginAttributes &aOriginAttrs,
                        nsTArray<nsCookie *> &aCookieList);

 protected:
  virtual ~nsCookieService();

  void PrefChanged(nsIPrefBranch *aPrefBranch);
  void InitDBStates();
  OpenDBResult TryInitDB(bool aDeleteExistingDB);
  void InitDBConn();
  nsresult InitDBConnInternal();
  nsresult CreateTableWorker(const char *aName);
  nsresult CreateIndex();
  nsresult CreateTable();
  nsresult CreateTableForSchemaVersion6();
  nsresult CreateTableForSchemaVersion5();
  void CloseDBStates();
  void CleanupCachedStatements();
  void CleanupDefaultDBConnection();
  void HandleDBClosed(DBState *aDBState);
  void HandleCorruptDB(DBState *aDBState);
  void RebuildCorruptDB(DBState *aDBState);
  OpenDBResult Read();
  mozilla::UniquePtr<ConstCookie> GetCookieFromRow(
      mozIStorageStatement *aRow, const OriginAttributes &aOriginAttributes);
  void EnsureReadComplete(bool aInitDBConn);
  nsresult NormalizeHost(nsCString &aHost);
  nsresult GetCookieStringCommon(nsIURI *aHostURI, nsIChannel *aChannel,
                                 bool aHttpBound, char **aCookie);
  void GetCookieStringInternal(nsIURI *aHostURI, bool aIsForeign,
                               bool aIsTrackingResource,
                               bool aFirstPartyStorageAccessGranted,
                               bool aIsSafeTopLevelNav, bool aIsTopLevelForeign,
                               bool aHttpBound,
                               const OriginAttributes &aOriginAttrs,
                               nsCString &aCookie);
  nsresult SetCookieStringCommon(nsIURI *aHostURI, const char *aCookieHeader,
                                 const char *aServerTime, nsIChannel *aChannel,
                                 bool aFromHttp);
  void SetCookieStringInternal(nsIURI *aHostURI, bool aIsForeign,
                               bool aIsTrackingResource,
                               bool aFirstPartyStorageAccessGranted,
                               nsDependentCString &aCookieHeader,
                               const nsCString &aServerTime, bool aFromHttp,
                               const OriginAttributes &aOriginAttrs,
                               nsIChannel *aChannel);
  bool SetCookieInternal(nsIURI *aHostURI, const nsCookieKey &aKey,
                         bool aRequireHostMatch, CookieStatus aStatus,
                         nsDependentCString &aCookieHeader, int64_t aServerTime,
                         bool aFromHttp, nsIChannel *aChannel);
  void AddInternal(const nsCookieKey &aKey, nsCookie *aCookie,
                   int64_t aCurrentTimeInUsec, nsIURI *aHostURI,
                   const char *aCookieHeader, bool aFromHttp);
  void RemoveCookieFromList(
      const nsListIter &aIter,
      mozIStorageBindingParamsArray *aParamsArray = nullptr);
  void AddCookieToList(const nsCookieKey &aKey, nsCookie *aCookie,
                       DBState *aDBState,
                       mozIStorageBindingParamsArray *aParamsArray,
                       bool aWriteToDB = true);
  void UpdateCookieInList(nsCookie *aCookie, int64_t aLastAccessed,
                          mozIStorageBindingParamsArray *aParamsArray);
  static bool GetTokenValue(nsACString::const_char_iterator &aIter,
                            nsACString::const_char_iterator &aEndIter,
                            nsDependentCSubstring &aTokenString,
                            nsDependentCSubstring &aTokenValue,
                            bool &aEqualsFound);
  static bool ParseAttributes(nsDependentCString &aCookieHeader,
                              nsCookieAttributes &aCookie);
  bool RequireThirdPartyCheck();
  static bool CheckDomain(nsCookieAttributes &aCookie, nsIURI *aHostURI,
                          const nsCString &aBaseDomain, bool aRequireHostMatch);
  static bool CheckPath(nsCookieAttributes &aCookie, nsIURI *aHostURI);
  static bool CheckPrefixes(nsCookieAttributes &aCookie, bool aSecureRequest);
  static bool GetExpiry(nsCookieAttributes &aCookie, int64_t aServerTime,
                        int64_t aCurrentTime);
  void RemoveAllFromMemory();
  already_AddRefed<nsIArray> PurgeCookies(int64_t aCurrentTimeInUsec);
  bool FindCookie(const nsCookieKey &aKey, const nsCString &aHost,
                  const nsCString &aName, const nsCString &aPath,
                  nsListIter &aIter);
  bool FindSecureCookie(const nsCookieKey &aKey, nsCookie *aCookie);
  void FindStaleCookies(nsCookieEntry *aEntry, int64_t aCurrentTime,
                        const mozilla::Maybe<bool> &aIsSecure,
                        nsTArray<nsListIter> &aOutput, uint32_t aLimit);
  void TelemetryForEvictingStaleCookie(nsCookie *aEvicted,
                                       int64_t oldestCookieTime);
  void NotifyAccepted(nsIChannel *aChannel);
  void NotifyRejected(nsIURI *aHostURI, nsIChannel *aChannel,
                      uint32_t aRejectedReason);
  void NotifyThirdParty(nsIURI *aHostURI, bool aAccepted, nsIChannel *aChannel);
  void NotifyChanged(nsISupports *aSubject, const char16_t *aData,
                     bool aOldCookieIsSession = false, bool aFromHttp = false);
  void NotifyPurged(nsICookie2 *aCookie);
  already_AddRefed<nsIArray> CreatePurgeList(nsICookie2 *aCookie);
  void CreateOrUpdatePurgeList(nsIArray **aPurgeList, nsICookie2 *aCookie);
  void UpdateCookieOldestTime(DBState *aDBState, nsCookie *aCookie);

  nsresult GetCookiesWithOriginAttributes(
      const mozilla::OriginAttributesPattern &aPattern,
      const nsCString &aBaseDomain, nsISimpleEnumerator **aEnumerator);
  nsresult RemoveCookiesWithOriginAttributes(
      const mozilla::OriginAttributesPattern &aPattern,
      const nsCString &aBaseDomain);

  /**
   * This method is a helper that allows calling nsICookieManager::Remove()
   * with OriginAttributes parameter.
   * NOTE: this could be added to a public interface if we happen to need it.
   */
  nsresult Remove(const nsACString &aHost, const OriginAttributes &aAttrs,
                  const nsACString &aName, const nsACString &aPath,
                  bool aBlocked);

 protected:
  // cached members.
  nsCOMPtr<nsICookiePermission> mPermissionService;
  nsCOMPtr<mozIThirdPartyUtil> mThirdPartyUtil;
  nsCOMPtr<nsIEffectiveTLDService> mTLDService;
  nsCOMPtr<nsIIDNService> mIDNService;
  nsCOMPtr<mozIStorageService> mStorageService;

  // we have two separate DB states: one for normal browsing and one for
  // private browsing, switching between them on a per-cookie-request basis.
  // this state encapsulates both the in-memory table and the on-disk DB.
  // note that the private states' dbConn should always be null - we never
  // want to be dealing with the on-disk DB when in private browsing.
  DBState *mDBState;
  RefPtr<DBState> mDefaultDBState;
  RefPtr<DBState> mPrivateDBState;

  // cached prefs
  uint8_t mCookieBehavior;  // BEHAVIOR_{ACCEPT, REJECTFOREIGN, REJECT,
                            // LIMITFOREIGN}
  bool mThirdPartySession;
  bool mThirdPartyNonsecureSession;
  bool mLeaveSecureAlone;
  uint16_t mMaxNumberOfCookies;
  uint16_t mMaxCookiesPerHost;
  uint16_t mCookieQuotaPerHost;
  int64_t mCookiePurgeAge;

  // thread
  nsCOMPtr<nsIThread> mThread;
  mozilla::Monitor mMonitor;
  mozilla::Atomic<bool> mInitializedDBStates;
  mozilla::Atomic<bool> mInitializedDBConn;
  mozilla::TimeStamp mEndInitDBConn;
  nsTArray<CookieDomainTuple> mReadArray;

  // friends!
  friend class DBListenerErrorHandler;
  friend class ReadCookieDBListener;
  friend class CloseCookieDBListener;

  static already_AddRefed<nsCookieService> GetSingleton();
  friend class mozilla::net::CookieServiceParent;
};

#endif  // nsCookieService_h__