subagent.c

snmp的源代码,已经在我的ubuntu下编译通过

        break;

    case AGENTX_MSG_RESPONSE:
        DEBUGMSGTL(("agentx/subagent", "  -> response\n"));
        return 1;

    case AGENTX_MSG_TESTSET:
        /*
         * XXXWWW we have to map this twice to both RESERVE1 and RESERVE2 
         */
        DEBUGMSGTL(("agentx/subagent", "  -> testset\n"));
        asi = save_set_vars(session, pdu);
        if (asi == NULL) {
            snmp_log(LOG_WARNING, "save_set_vars() failed\n");
            return 1;
        }
        asi->mode = pdu->command = SNMP_MSG_INTERNAL_SET_RESERVE1;
        mycallback = handle_subagent_set_response;
        retmagic = asi;
        break;

    case AGENTX_MSG_COMMITSET:
        DEBUGMSGTL(("agentx/subagent", "  -> commitset\n"));
        asi = restore_set_vars(session, pdu);
        if (asi == NULL) {
            snmp_log(LOG_WARNING, "restore_set_vars() failed\n");
            return 1;
        }
        if (asi->mode != SNMP_MSG_INTERNAL_SET_RESERVE2) {
            snmp_log(LOG_WARNING,
                     "dropping bad AgentX request (wrong mode %d)\n",
                     asi->mode);
            return 1;
        }
        asi->mode = pdu->command = SNMP_MSG_INTERNAL_SET_ACTION;
        mycallback = handle_subagent_set_response;
        retmagic = asi;
        break;

    case AGENTX_MSG_CLEANUPSET:
        DEBUGMSGTL(("agentx/subagent", "  -> cleanupset\n"));
        asi = restore_set_vars(session, pdu);
        if (asi == NULL) {
            snmp_log(LOG_WARNING, "restore_set_vars() failed\n");
            return 1;
        }
        if (asi->mode == SNMP_MSG_INTERNAL_SET_RESERVE1 ||
            asi->mode == SNMP_MSG_INTERNAL_SET_RESERVE2) {
            asi->mode = pdu->command = SNMP_MSG_INTERNAL_SET_FREE;
        } else if (asi->mode == SNMP_MSG_INTERNAL_SET_ACTION) {
            asi->mode = pdu->command = SNMP_MSG_INTERNAL_SET_COMMIT;
        } else {
            snmp_log(LOG_WARNING,
                     "dropping bad AgentX request (wrong mode %d)\n",
                     asi->mode);
            return 1;
        }
        mycallback = handle_subagent_set_response;
        retmagic = asi;
        break;

    case AGENTX_MSG_UNDOSET:
        DEBUGMSGTL(("agentx/subagent", "  -> undoset\n"));
        asi = restore_set_vars(session, pdu);
        if (asi == NULL) {
            snmp_log(LOG_WARNING, "restore_set_vars() failed\n");
            return 1;
        }
        asi->mode = pdu->command = SNMP_MSG_INTERNAL_SET_UNDO;
        mycallback = handle_subagent_set_response;
        retmagic = asi;
        break;

    default:
        DEBUGMSGTL(("agentx/subagent", "  -> unknown command %d (%02x)\n",
                    pdu->command, pdu->command));
        return 0;
    }

    /*
     * submit the pdu to the internal handler 
     */

    /*
     * We have to clone the PDU here, because when we return from this
     * callback, sess_process_packet will free(pdu), but this call also
     * free()s its argument PDU.  
     */

    internal_pdu = snmp_clone_pdu(pdu);
    internal_pdu->contextName = internal_pdu->community;
    internal_pdu->contextNameLen = internal_pdu->community_len;
    internal_pdu->community = NULL;
    internal_pdu->community_len = 0;
    snmp_async_send(agentx_callback_sess, internal_pdu, mycallback,
                    retmagic);
    return 1;
}

int
handle_subagent_response(int op, netsnmp_session * session, int reqid,
                         netsnmp_pdu *pdu, void *magic)
{
    ns_subagent_magic *smagic = (ns_subagent_magic *) magic;
    netsnmp_variable_list *u = NULL, *v = NULL;
    int             rc = 0;

    if (op != NETSNMP_CALLBACK_OP_RECEIVED_MESSAGE || magic == NULL) {
        return 1;
    }

    pdu = snmp_clone_pdu(pdu);
    DEBUGMSGTL(("agentx/subagent",
                "handling AgentX response (cmd 0x%02x orig_cmd 0x%02x)\n",
                pdu->command, smagic->original_command));

    if (pdu->command == SNMP_MSG_INTERNAL_SET_FREE ||
        pdu->command == SNMP_MSG_INTERNAL_SET_UNDO ||
        pdu->command == SNMP_MSG_INTERNAL_SET_COMMIT) {
        free_set_vars(smagic->session, pdu);
    }

    if (smagic->original_command == AGENTX_MSG_GETNEXT) {
        DEBUGMSGTL(("agentx/subgaent",
                    "do getNext scope processing %p %p\n", smagic->ovars,
                    pdu->variables));
        for (u = smagic->ovars, v = pdu->variables; u != NULL && v != NULL;
             u = u->next_variable, v = v->next_variable) {
            if (snmp_oid_compare
                (u->val.objid, u->val_len / sizeof(oid), nullOid,
                 nullOidLen) != 0) {
                /*
                 * The master agent requested scoping for this variable.  
                 */
                rc = snmp_oid_compare(v->name, v->name_length,
                                      u->val.objid,
                                      u->val_len / sizeof(oid));
                DEBUGMSGTL(("agentx/subagent", "result "));
                DEBUGMSGOID(("agentx/subagent", v->name, v->name_length));
                DEBUGMSG(("agentx/subagent", " scope to "));
                DEBUGMSGOID(("agentx/subagent",
                             u->val.objid, u->val_len / sizeof(oid)));
                DEBUGMSG(("agentx/subagent", " result %d\n", rc));

                if (rc >= 0) {
                    /*
                     * The varbind is out of scope.  From RFC2741, p. 66: "If
                     * the subagent cannot locate an appropriate variable,
                     * v.name is set to the starting OID, and the VarBind is
                     * set to `endOfMibView'".  
                     */
                    snmp_set_var_objid(v, u->name, u->name_length);
                    snmp_set_var_typed_value(v, SNMP_ENDOFMIBVIEW, 0, 0);
                    DEBUGMSGTL(("agentx/subagent",
                                "scope violation -- return endOfMibView\n"));
                }
            } else {
                DEBUGMSGTL(("agentx/subagent", "unscoped var\n"));
            }
        }
    }

    /*
     * XXXJBPN: similar for GETBULK but the varbinds can get re-ordered I
     * think which makes it er more difficult.  
     */

    if (smagic->ovars != NULL) {
        snmp_free_varbind(smagic->ovars);
    }

    pdu->command = AGENTX_MSG_RESPONSE;
    pdu->version = smagic->session->version;

    if (!snmp_send(smagic->session, pdu)) {
        snmp_free_pdu(pdu);
    }
    DEBUGMSGTL(("agentx/subagent", "  FINISHED\n"));
    free(smagic);
    return 1;
}

int
handle_subagent_set_response(int op, netsnmp_session * session, int reqid,
                             netsnmp_pdu *pdu, void *magic)
{
    netsnmp_session *retsess;
    struct agent_netsnmp_set_info *asi;

    if (op != NETSNMP_CALLBACK_OP_RECEIVED_MESSAGE || magic == NULL) {
        return 1;
    }

    DEBUGMSGTL(("agentx/subagent",
                "handling agentx subagent set response (mode=%d,req=0x%x,"
                "trans=0x%x,sess=0x%x)\n",
                pdu->command, pdu->reqid,pdu->transid, pdu->sessid));
    pdu = snmp_clone_pdu(pdu);

    asi = (struct agent_netsnmp_set_info *) magic;
    retsess = asi->sess;
    asi->errstat = pdu->errstat;

    if (asi->mode == SNMP_MSG_INTERNAL_SET_RESERVE1) {
        /*
         * reloop for RESERVE2 mode, an internal only agent mode 
         */
        /*
         * XXX: check exception statuses of reserve1 first 
         */
        if (!pdu->errstat) {
            asi->mode = pdu->command = SNMP_MSG_INTERNAL_SET_RESERVE2;
            snmp_async_send(agentx_callback_sess, pdu,
                            handle_subagent_set_response, asi);
            DEBUGMSGTL(("agentx/subagent",
                        "  going from RESERVE1 -> RESERVE2\n"));
            return 1;
        }
    } else {
        if (asi->mode == SNMP_MSG_INTERNAL_SET_FREE ||
            asi->mode == SNMP_MSG_INTERNAL_SET_UNDO ||
            asi->mode == SNMP_MSG_INTERNAL_SET_COMMIT) {
            free_set_vars(retsess, pdu);
        }
        snmp_free_varbind(pdu->variables);
        pdu->variables = NULL;  /* the variables were added by us */
    }

    netsnmp_assert(retsess != NULL);
    pdu->command = AGENTX_MSG_RESPONSE;
    pdu->version = retsess->version;

    if (!snmp_send(retsess, pdu)) {
        snmp_free_pdu(pdu);
    }
    DEBUGMSGTL(("agentx/subagent", "  FINISHED\n"));
    return 1;
}



int
agentx_registration_callback(int majorID, int minorID, void *serverarg,
                             void *clientarg)
{
    struct register_parameters *reg_parms =
        (struct register_parameters *) serverarg;
    netsnmp_session *agentx_ss = (netsnmp_session *) clientarg;

    if (minorID == SNMPD_CALLBACK_REGISTER_OID)
        return agentx_register(agentx_ss,
                               reg_parms->name, reg_parms->namelen,
                               reg_parms->priority,
                               reg_parms->range_subid,
                               reg_parms->range_ubound, reg_parms->timeout,
                               reg_parms->flags,
                               reg_parms->contextName);
    else
        return agentx_unregister(agentx_ss,
                                 reg_parms->name, reg_parms->namelen,
                                 reg_parms->priority,
                                 reg_parms->range_subid,
                                 reg_parms->range_ubound,
                                 reg_parms->contextName);
}


#ifdef USING_MIBII_SYSORTABLE_MODULE
int
agentx_sysOR_callback(int majorID, int minorID, void *serverarg,
                      void *clientarg)
{
    struct register_sysOR_parameters *reg_parms =
        (struct register_sysOR_parameters *) serverarg;
    netsnmp_session *agentx_ss = (netsnmp_session *) clientarg;

    if (minorID == SNMPD_CALLBACK_REG_SYSOR)
        return agentx_add_agentcaps(agentx_ss,
                                    reg_parms->name, reg_parms->namelen,
                                    reg_parms->descr);
    else
        return agentx_remove_agentcaps(agentx_ss,
                                       reg_parms->name,
                                       reg_parms->namelen);
}
#endif


static int
subagent_shutdown(int majorID, int minorID, void *serverarg, void *clientarg)
{
    netsnmp_session *thesession = (netsnmp_session *)clientarg;
    DEBUGMSGTL(("agentx/subagent", "shutting down session....\n"));
    if (thesession == NULL) {
	DEBUGMSGTL(("agentx/subagent", "Empty session to shutdown\n"));
	main_session = NULL;
	return 0;
    }
    agentx_close_session(thesession, AGENTX_CLOSE_SHUTDOWN);
    snmp_close(thesession);
    main_session = NULL;
    DEBUGMSGTL(("agentx/subagent", "shut down finished.\n"));
    return 1;
}



/*
 * Register all the "standard" AgentX callbacks for the given session.  
 */

void
agentx_register_callbacks(netsnmp_session * s)
{
    DEBUGMSGTL(("agentx/subagent",
                "registering callbacks for session %p\n", s));
    snmp_register_callback(SNMP_CALLBACK_LIBRARY,
                           SNMP_CALLBACK_POST_READ_CONFIG,