src/snmp/Forwarder.cc

   1 /*
   2  * $Id$
   3  *
   4  * DEBUG: section 49    SNMP Interface
   5  *
   6  */
   7
   8 #include "squid.h"
   9 #include "base/TextException.h"
  10 #include "CommCalls.h"
  11 #include "comm.h"
  12 #include "globals.h"
  13 #include "ipc/Port.h"
  14 #include "snmp_core.h"
  15 #include "snmp/Forwarder.h"
  16 #include "snmp/Request.h"
  17 #include "snmp/Response.h"
  18
  19
  20 CBDATA_NAMESPACED_CLASS_INIT(Snmp, Forwarder);
  21
  22
  23 Snmp::Forwarder::Forwarder(const Pdu& aPdu, const Session& aSession, int aFd,
  24                            const Ip::Address& anAddress):
  25         Ipc::Forwarder(new Request(KidIdentifier, 0, aPdu, aSession, aFd, anAddress), 2),
  26         fd(aFd)
  27 {
  28     debugs(49, 5, HERE << "FD " << aFd);
  29     Must(fd >= 0);
  30     closer = asyncCall(49, 5, "Snmp::Forwarder::noteCommClosed",
  31                        CommCbMemFunT<Forwarder, CommCloseCbParams>(this, &Forwarder::noteCommClosed));
  32     comm_add_close_handler(fd, closer);
  33 }
  34
  35 /// removes our cleanup handler of the client connection socket
  36 void
  37 Snmp::Forwarder::cleanup()
  38 {
  39     if (fd >= 0) {
  40         if (closer != NULL) {
  41             comm_remove_close_handler(fd, closer);
  42             closer = NULL;
  43         }
  44         fd = -1;
  45     }
  46 }
  47
  48 /// called when the client socket gets closed by some external force
  49 void
  50 Snmp::Forwarder::noteCommClosed(const CommCloseCbParams& params)
  51 {
  52     debugs(49, 5, HERE);
  53     Must(fd == params.fd);
  54     fd = -1;
  55     mustStop("commClosed");
  56 }
  57
  58 void
  59 Snmp::Forwarder::handleTimeout()
  60 {
  61     sendError(SNMP_ERR_RESOURCEUNAVAILABLE);
  62     Ipc::Forwarder::handleTimeout();
  63 }
  64
  65 void
  66 Snmp::Forwarder::handleException(const std::exception& e)
  67 {
  68     debugs(49, 3, HERE << e.what());
  69     if (fd >= 0)
  70         sendError(SNMP_ERR_GENERR);
  71     Ipc::Forwarder::handleException(e);
  72 }
  73
  74 /// send error SNMP response
  75 void
  76 Snmp::Forwarder::sendError(int error)
  77 {
  78     debugs(49, 3, HERE);
  79     Snmp::Request& req = static_cast<Snmp::Request&>(*request);
  80     req.pdu.command = SNMP_PDU_RESPONSE;
  81     req.pdu.errstat = error;
  82     u_char buffer[SNMP_REQUEST_SIZE];
  83     int len = sizeof(buffer);
  84     snmp_build(&req.session, &req.pdu, buffer, &len);
  85     comm_udp_sendto(fd, req.address, buffer, len);
  86 }
  87
  88 void
  89 Snmp::SendResponse(unsigned int requestId, const Pdu& pdu)
  90 {
  91     debugs(49, 5, HERE);
  92     // snmpAgentResponse() can modify arg
  93     Pdu tmp = pdu;
  94     Snmp::Response response(requestId);
  95     snmp_pdu* response_pdu = NULL;
  96     try {
  97         response_pdu = snmpAgentResponse(&tmp);
  98         Must(response_pdu != NULL);
  99         response.pdu = static_cast<Pdu&>(*response_pdu);
 100         snmp_free_pdu(response_pdu);
 101     } catch (const std::exception& e) {
 102         debugs(49, DBG_CRITICAL, HERE << e.what());
 103         response.pdu.command = SNMP_PDU_RESPONSE;
 104         response.pdu.errstat = SNMP_ERR_GENERR;
 105     }
 106     Ipc::TypedMsgHdr message;
 107     response.pack(message);
 108     Ipc::SendMessage(Ipc::coordinatorAddr, message);
 109 }