src/snmp/Forwarder.cc

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