src/comm/Connection.h

   1 /*
   2  * Copyright (C) 1996-2025 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 /* DEBUG: section 05    Socket Functions */
  10
  11 #ifndef SQUID_SRC_COMM_CONNECTION_H
  12 #define SQUID_SRC_COMM_CONNECTION_H
  13
  14 #include "base/CodeContext.h"
  15 #include "base/InstanceId.h"
  16 #include "comm/forward.h"
  17 #include "defines.h"
  18 #if USE_SQUID_EUI
  19 #include "eui/Eui48.h"
  20 #include "eui/Eui64.h"
  21 #endif
  22 #include "hier_code.h"
  23 #include "ip/Address.h"
  24 #include "ip/forward.h"
  25 #include "mem/forward.h"
  26 #include "time/gadgets.h"
  27
  28 #include <iosfwd>
  29 #include <ostream>
  30
  31 class CachePeer;
  32
  33 namespace Security
  34 {
  35 class NegotiationHistory;
  36 };
  37
  38 namespace Comm
  39 {
  40
  41 /* TODO: make these a struct of boolean flags members in the connection instead of a bitmap.
  42  * we can't do that until all non-comm code uses Commm::Connection objects to create FD
  43  * currently there is code still using comm_open() and comm_openex() synchronously!!
  44  */
  45 #define COMM_UNSET              0x00
  46 #define COMM_NONBLOCKING        0x01  // default flag.
  47 #define COMM_NOCLOEXEC          0x02
  48 #define COMM_REUSEADDR          0x04  // shared FD may be both accept()ing and read()ing
  49 #define COMM_DOBIND             0x08  // requires a bind()
  50 #define COMM_TRANSPARENT        0x10  // arrived via TPROXY
  51 #define COMM_INTERCEPTION       0x20  // arrived via NAT
  52 #define COMM_REUSEPORT          0x40 //< needs SO_REUSEPORT
  53 /// not registered with Comm and not owned by any connection-closing code
  54 #define COMM_ORPHANED           0x80
  55 /// Internal Comm optimization: Keep the source port unassigned until connect(2)
  56 #define COMM_DOBIND_PORT_LATER 0x100
  57
  58 /**
  59  * Store data about the physical and logical attributes of a connection.
  60  *
  61  * Some link state can be inferred from the data, however this is not an
  62  * object for state data. But a semantic equivalent for FD with easily
  63  * accessible cached properties not requiring repeated complex lookups.
  64  *
  65  * Connection properties may be changed until the connection is opened.
  66  * Properties should be considered read-only outside of the Comm layer
  67  * code once the connection is open.
  68  *
  69  * These objects should not be passed around directly,
  70  * but a Comm::ConnectionPointer should be passed instead.
  71  */
  72 class Connection: public CodeContext
  73 {
  74     MEMPROXY_CLASS(Comm::Connection);
  75
  76 public:
  77     Connection();
  78
  79     /** Clear the connection properties and close any open socket. */
  80     ~Connection() override;
  81
  82     /// To prevent accidental copying of Connection objects that we started to
  83     /// open or that are open, use cloneProfile() instead.
  84     Connection(const Connection &&) = delete;
  85
  86     /// Create a new closed Connection with the same configuration as this one.
  87     ConnectionPointer cloneProfile() const;
  88
  89     /// close the still-open connection when its last reference is gone
  90     void enterOrphanage() { flags |= COMM_ORPHANED; }
  91     /// resume relying on owner(s) to initiate an explicit connection closure
  92     void leaveOrphanage() { flags &= ~COMM_ORPHANED; }
  93
  94     /** Close any open socket. */
  95     void close();
  96
  97     /** Synchronize with Comm: Somebody closed our connection. */
  98     void noteClosure();
  99
 100     /** determine whether this object describes an active connection or not. */
 101     bool isOpen() const { return (fd >= 0); }
 102
 103     /** Alter the stored IP address pair.
 104      * WARNING: Does not ensure matching IPv4/IPv6 are supplied.
 105      */
 106     void setAddrs(const Ip::Address &aLocal, const Ip::Address &aRemote) {local = aLocal; remote = aRemote;}
 107
 108     /** retrieve the CachePeer pointer for use.
 109      * The caller is responsible for all CBDATA operations regarding the
 110      * used of the pointer returned.
 111      */
 112     CachePeer * getPeer() const;
 113
 114     /** alter the stored CachePeer pointer.
 115      * Perform appropriate CBDATA operations for locking the CachePeer pointer
 116      */
 117     void setPeer(CachePeer * p);
 118
 119     /// whether this is a connection to a cache_peer that was removed during reconfiguration
 120     bool toGoneCachePeer() const;
 121
 122     /** The time the connection started */
 123     time_t startTime() const {return startTime_;}
 124
 125     /** The connection lifetime */
 126     time_t lifeTime() const {return squid_curtime - startTime_;}
 127
 128     /** The time left for this connection*/
 129     time_t timeLeft(const time_t idleTimeout) const;
 130
 131     /// Connection establishment timeout for callers that have already decided
 132     /// to connect(2), either for the first time or after checking
 133     /// EnoughTimeToReForward() during any re-forwarding attempts.
 134     /// \returns the time left for this connection to become connected
 135     /// \param fwdStart The start time of the peer selection/connection process.
 136     time_t connectTimeout(const time_t fwdStart) const;
 137
 138     void noteStart() {startTime_ = squid_curtime;}
 139
 140     Security::NegotiationHistory *tlsNegotiations();
 141     const Security::NegotiationHistory *hasTlsNegotiations() const {return tlsHistory;}
 142
 143     /* CodeContext API */
 144     ScopedId codeContextGist() const override;
 145     std::ostream &detailCodeContext(std::ostream &os) const override;
 146
 147 public:
 148     /** Address/Port for the Squid end of a TCP link. */
 149     Ip::Address local;
 150
 151     /** Address for the Remote end of a TCP link. */
 152     Ip::Address remote;
 153
 154     /** Hierarchy code for this connection link */
 155     hier_code peerType;
 156
 157     /** Socket used by this connection. Negative if not open. */
 158     int fd;
 159
 160     /** Quality of Service TOS values currently sent on this connection */
 161     tos_t tos;
 162
 163     /** Netfilter MARK values currently sent on this connection
 164      * In case of FTP, the MARK will be sent on data connections as well.
 165      */
 166     nfmark_t nfmark;
 167
 168     /** Netfilter CONNMARK value previously retrieved from this connection
 169      * In case of FTP, the CONNMARK will NOT be applied to data connections, for one main reason:
 170      * the CONNMARK could be set by a third party like iptables and overwriting it in squid may
 171      * cause side effects and break CONNMARK-based policy. In other words, data connection is
 172      * related to control connection, but it's not the same.
 173      */
 174     nfmark_t nfConnmark = 0;
 175
 176     /** COMM flags set on this connection */
 177     int flags;
 178
 179 #if USE_SQUID_EUI
 180     Eui::Eui48 remoteEui48;
 181     Eui::Eui64 remoteEui64;
 182 #endif
 183
 184     InstanceId<Connection, uint64_t> id;
 185
 186 private:
 187     /** cache_peer data object (if any) */
 188     CachePeer *peer_;
 189
 190     /** The time the connection object was created */
 191     time_t startTime_;
 192
 193     /** TLS connection details*/
 194     Security::NegotiationHistory *tlsHistory;
 195 };
 196
 197 std::ostream &operator <<(std::ostream &, const Connection &);
 198
 199 inline std::ostream &
 200 operator <<(std::ostream &os, const ConnectionPointer &conn)
 201 {
 202     if (conn != nullptr)
 203         os << *conn;
 204     return os;
 205 }
 206
 207 } // namespace Comm
 208
 209 #endif /* SQUID_SRC_COMM_CONNECTION_H */
 210