/*
 * Portions of this file are subject to the following copyright(s).  See
 * the Net-SNMP's COPYING file for more details and other copyrights
 * that may apply:
 *
 * Portions of this file are copyrighted by:
 * Copyright (c) 2016 VMware, Inc. All rights reserved.
 * Use is subject to license terms specified in the COPYING file
 * distributed with the Net-SNMP package.
 */

#include <net-snmp/net-snmp-config.h>
#include <net-snmp/net-snmp-features.h>
#include <net-snmp/net-snmp-includes.h>
#include <net-snmp/agent/net-snmp-agent-includes.h>
#include <net-snmp/agent/sysORTable.h>

#include <net-snmp/agent/snmp_get_statistic.h>

#include "snmp_mib.h"
#include "system_mib.h"
#include "updates.h"
#include "agent_global_vars.h"

netsnmp_feature_require(helper_statistics);
#ifndef NETSNMP_NO_WRITE_SUPPORT
netsnmp_feature_require(check_vb_truthvalue);
#endif /* NETSNMP_NO_WRITE_SUPPORT */

#define SNMP_OID 1, 3, 6, 1, 2, 1, 11

static const oid snmp_oid[] = { SNMP_OID };

static int
snmp_enableauthentraps_store(int a, int b, void *c, void *d)
{
    char            line[SNMP_MAXBUF_SMALL];

    if (snmp_enableauthentrapsset > 0) {
        snprintf(line, SNMP_MAXBUF_SMALL, "pauthtrapenable %ld",
                 snmp_enableauthentraps);
        snmpd_store_config(line);
    }
    return 0;
}

static int
handle_truthvalue(netsnmp_mib_handler *handler,
                  netsnmp_handler_registration *reginfo,
                  netsnmp_agent_request_info *reqinfo,
                  netsnmp_request_info *requests)
{
#ifndef NETSNMP_NO_WRITE_SUPPORT
    if (reqinfo->mode == MODE_SET_RESERVE1) {
        int res = netsnmp_check_vb_truthvalue(requests->requestvb);
        if (res != SNMP_ERR_NOERROR)
            netsnmp_request_set_error(requests, res);
    }
#endif /* !NETSNMP_NO_WRITE_SUPPORT */
    return SNMP_ERR_NOERROR;
}

static netsnmp_mib_handler*
netsnmp_get_truthvalue(void)
{
    netsnmp_mib_handler* hnd =
        netsnmp_create_handler("truthvalue", handle_truthvalue);
    if (hnd)
        hnd->flags |= MIB_HANDLER_AUTO_NEXT;
    return hnd;
}

static int
handle_snmp(netsnmp_mib_handler *handler,
	    netsnmp_handler_registration *reginfo,
	    netsnmp_agent_request_info *reqinfo,
	    netsnmp_request_info *requests)
{
    switch(requests->requestvb->name[OID_LENGTH(snmp_oid)]) {
    case 7:
    case 23:
    case 30:
        netsnmp_set_request_error(reqinfo, requests, SNMP_NOSUCHOBJECT);
        break;
    default:
	break;
    }
    return SNMP_ERR_NOERROR;
}

/** Initializes the snmp module */
void
init_snmp_mib(void)
{
    DEBUGMSGTL(("snmp", "Initializing\n"));

    NETSNMP_REGISTER_STATISTIC_HANDLER(
        netsnmp_create_handler_registration(
            "mibII/snmp", handle_snmp, snmp_oid, OID_LENGTH(snmp_oid),
            HANDLER_CAN_RONLY),
        1, SNMP);
    {
        oid snmpEnableAuthenTraps_oid[] = { SNMP_OID, 30, 0 };
	static netsnmp_watcher_info enableauthen_info;
        netsnmp_mib_handler *handler;
        netsnmp_handler_registration *reg =
            netsnmp_create_update_handler_registration(
                "mibII/snmpEnableAuthenTraps",
                snmpEnableAuthenTraps_oid,
                OID_LENGTH(snmpEnableAuthenTraps_oid),
#ifndef NETSNMP_NO_WRITE_SUPPORT
                HANDLER_CAN_RWRITE,
#else
                HANDLER_CAN_RONLY,
#endif /* !NETSNMP_NO_WRITE_SUPPORT */
                &snmp_enableauthentrapsset);
        handler = netsnmp_get_truthvalue();
        if (!handler ||
            (netsnmp_inject_handler(reg, handler) != SNMPERR_SUCCESS)) {
            snmp_log(LOG_ERR,
                     "could not create mibII/snmpEnableAuthenTraps handler\n");
            if (handler)
                netsnmp_handler_free(handler);
            netsnmp_handler_registration_free(reg);
            return;
        }
        netsnmp_register_watched_instance(
            reg,
            netsnmp_init_watcher_info(
		&enableauthen_info,
                &snmp_enableauthentraps, sizeof(snmp_enableauthentraps),
                ASN_INTEGER, WATCHER_FIXED_SIZE));
    }

#ifdef USING_MIBII_SYSTEM_MIB_MODULE
    if (++system_module_count == 3)
        REGISTER_SYSOR_TABLE(system_module_oid, system_module_oid_len,
                             "The MIB module for SNMPv2 entities");
#endif
    snmp_register_callback(SNMP_CALLBACK_LIBRARY, SNMP_CALLBACK_STORE_DATA,
                           snmp_enableauthentraps_store, NULL);
}