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