src/FwdState.h

   1 /*
   2  * Copyright (C) 1996-2015 The Squid Software Foundation and contributors
   3  *
   4  * Squid software is distributed under GPLv2+ license and includes
   5  * contributions from numerous individuals and organizations.
   6  * Please see the COPYING and CONTRIBUTORS files for details.
   7  */
   8
   9 #ifndef SQUID_FORWARD_H
  10 #define SQUID_FORWARD_H
  11
  12 #include "base/RefCount.h"
  13 #include "comm.h"
  14 #include "comm/Connection.h"
  15 #include "err_type.h"
  16 #include "fde.h"
  17 #include "http/StatusCode.h"
  18 #include "ip/Address.h"
  19 #include "security/forward.h"
  20 #if USE_OPENSSL
  21 #include "ssl/support.h"
  22 #endif
  23
  24 /* forward decls */
  25
  26 class AccessLogEntry;
  27 typedef RefCount<AccessLogEntry> AccessLogEntryPointer;
  28 class PconnPool;
  29 typedef RefCount<PconnPool> PconnPoolPointer;
  30 class ErrorState;
  31 class HttpRequest;
  32
  33 #if USE_OPENSSL
  34 namespace Ssl
  35 {
  36 class ErrorDetail;
  37 class CertValidationResponse;
  38 };
  39 #endif
  40
  41 /**
  42  * Returns the TOS value that we should be setting on the connection
  43  * to the server, based on the ACL.
  44  */
  45 tos_t GetTosToServer(HttpRequest * request);
  46
  47 /**
  48  * Returns the Netfilter mark value that we should be setting on the
  49  * connection to the server, based on the ACL.
  50  */
  51 nfmark_t GetNfmarkToServer(HttpRequest * request);
  52
  53 /// Sets initial TOS value and Netfilter for the future outgoing connection.
  54 void GetMarkingsToServer(HttpRequest * request, Comm::Connection &conn);
  55
  56 class HelperReply;
  57
  58 class FwdState : public RefCountable
  59 {
  60     CBDATA_CLASS(FwdState);
  61
  62 public:
  63     typedef RefCount<FwdState> Pointer;
  64     ~FwdState();
  65     static void initModule();
  66
  67     /// Initiates request forwarding to a peer or origin server.
  68     static void Start(const Comm::ConnectionPointer &client, StoreEntry *, HttpRequest *, const AccessLogEntryPointer &alp);
  69     /// Same as Start() but no master xaction info (AccessLogEntry) available.
  70     static void fwdStart(const Comm::ConnectionPointer &client, StoreEntry *, HttpRequest *);
  71
  72     /// This is the real beginning of server connection. Call it whenever
  73     /// the forwarding server destination has changed and a new one needs to be opened.
  74     /// Produces the cannot-forward error on fail if no better error exists.
  75     void startConnectionOrFail();
  76
  77     void fail(ErrorState *err);
  78     void unregister(Comm::ConnectionPointer &conn);
  79     void unregister(int fd);
  80     void complete();
  81     void handleUnregisteredServerEnd();
  82     int reforward();
  83     bool reforwardableStatus(const Http::StatusCode s) const;
  84     void serverClosed(int fd);
  85     void connectStart();
  86     void connectDone(const Comm::ConnectionPointer & conn, Comm::Flag status, int xerrno);
  87     void connectTimeout(int fd);
  88     time_t timeLeft() const; ///< the time left before the forwarding timeout expired
  89     bool checkRetry();
  90     bool checkRetriable();
  91     void dispatch();
  92     /// Pops a connection from connection pool if available. If not
  93     /// checks the peer stand-by connection pool for available connection.
  94     Comm::ConnectionPointer pconnPop(const Comm::ConnectionPointer &dest, const char *domain);
  95     void pconnPush(Comm::ConnectionPointer & conn, const char *domain);
  96
  97     bool dontRetry() { return flags.dont_retry; }
  98
  99     void dontRetry(bool val) { flags.dont_retry = val; }
 100
 101     /** return a ConnectionPointer to the current server connection (may or may not be open) */
 102     Comm::ConnectionPointer const & serverConnection() const { return serverConn; };
 103
 104 private:
 105     // hidden for safer management of self; use static fwdStart
 106     FwdState(const Comm::ConnectionPointer &client, StoreEntry *, HttpRequest *, const AccessLogEntryPointer &alp);
 107     void start(Pointer aSelf);
 108
 109 #if STRICT_ORIGINAL_DST
 110     void selectPeerForIntercepted();
 111 #endif
 112     static void logReplyStatus(int tries, const Http::StatusCode status);
 113     void doneWithRetries();
 114     void completed();
 115     void retryOrBail();
 116     ErrorState *makeConnectingError(const err_type type) const;
 117     void connectedToPeer(Security::EncryptorAnswer &answer);
 118     static void RegisterWithCacheManager(void);
 119
 120     /// stops monitoring server connection for closure and updates pconn stats
 121     void closeServerConnection(const char *reason);
 122
 123     void syncWithServerConn(const char *host);
 124
 125 public:
 126     StoreEntry *entry;
 127     HttpRequest *request;
 128     AccessLogEntryPointer al; ///< info for the future access.log entry
 129
 130     static void abort(void*);
 131
 132 private:
 133     Pointer self;
 134     ErrorState *err;
 135     Comm::ConnectionPointer clientConn;        ///< a possibly open connection to the client.
 136     time_t start_t;
 137     int n_tries;
 138
 139     // AsyncCalls which we set and may need cancelling.
 140     struct {
 141         AsyncCall::Pointer connector;  ///< a call linking us to the ConnOpener producing serverConn.
 142     } calls;
 143
 144     struct {
 145         bool connected_okay; ///< TCP link ever opened properly. This affects retry of POST,PUT,CONNECT,etc
 146         bool dont_retry;
 147         bool forward_completed;
 148     } flags;
 149
 150     /** connections to open, in order, until successful */
 151     Comm::ConnectionList serverDestinations;
 152
 153     Comm::ConnectionPointer serverConn; ///< a successfully opened connection to a server.
 154
 155     /// possible pconn race states
 156     typedef enum { raceImpossible, racePossible, raceHappened } PconnRace;
 157     PconnRace pconnRace; ///< current pconn race state
 158 };
 159
 160 void getOutgoingAddress(HttpRequest * request, Comm::ConnectionPointer conn);
 161
 162 #endif /* SQUID_FORWARD_H */
 163