src/snmp/Forwarder.cc

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