//%LICENSE////////////////////////////////////////////////////////////////
//
// Licensed to The Open Group (TOG) under one or more contributor license
// agreements.  Refer to the OpenPegasusNOTICE.txt file distributed with
// this work for additional information regarding copyright ownership.
// Each contributor licenses this file to you under the OpenPegasus Open
// Source License; you may not use this file except in compliance with the
// License.
//
// Permission is hereby granted, free of charge, to any person obtaining a
// copy of this software and associated documentation files (the "Software"),
// to deal in the Software without restriction, including without limitation
// the rights to use, copy, modify, merge, publish, distribute, sublicense,
// and/or sell copies of the Software, and to permit persons to whom the
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// The above copyright notice and this permission notice shall be included
// in all copies or substantial portions of the Software.
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// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
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// SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
//
//////////////////////////////////////////////////////////////////////////
//
//%/////////////////////////////////////////////////////////////////////////////

#include <Pegasus/Common/Packer.h>
#include <Pegasus/Common/Tracer.h>
#include "snmpDeliverTrap_netsnmp.h"

PEGASUS_NAMESPACE_BEGIN

void snmpDeliverTrap_netsnmp::initialize()
{
    PEG_METHOD_ENTER(TRC_IND_HANDLER, "snmpDeliverTrap_netsnmp::initialize");

    // Defined default MIB modules (in net-snmp-config.h) do not need to be
    // loaded and loading them can cause some stderr;
    // use environment variable MIBS to override the default MIB modules.
    // If there is no MIBS environment variable, add it in.
    char* envVar;
    envVar = getenv("MIBS");

    if (envVar == NULL)
    {
        putenv("MIBS=");
    }

    // Initialize the mib reader
    netsnmp_set_mib_directory("");
    init_mib();

    // Initializes the SNMP library
    init_snmp("snmpIndicationHandler");

    // don't load/save persistent file
#ifdef NETSNMP_DS_LIB_DONT_PERSIST_STATE
    netsnmp_ds_set_boolean(NETSNMP_DS_LIBRARY_ID,
        NETSNMP_DS_LIB_DONT_PERSIST_STATE, 1);
#endif

    // windows32 specific initialization (is a NOOP on unix)
    SOCK_STARTUP;

    PEG_METHOD_EXIT();
}

void snmpDeliverTrap_netsnmp::terminate()
{
    PEG_METHOD_ENTER(TRC_IND_HANDLER, "snmpDeliverTrap_netsnmp::terminate");

    // Shuts down the application, and appropriate clean up
    snmp_shutdown("snmpIndicationHandler");

    SOCK_CLEANUP;

    PEG_METHOD_EXIT();
}

void snmpDeliverTrap_netsnmp::deliverTrap(
    const String& trapOid,
    const String& securityName,
    const String& targetHost,
    const Uint16& targetHostFormat,
    const String& otherTargetHostFormat,
    const Uint32& portNumber,
    const Uint16& snmpVersion,
    const String& engineID,
    const Array<String>& vbOids,
    const Array<String>& vbTypes,
    const Array<String>& vbValues)
{

    PEG_METHOD_ENTER(TRC_IND_HANDLER, "snmpDeliverTrap_netsnmp::deliverTrap");

    void* sessionHandle;
    struct snmp_session* sessionPtr;

    struct snmp_pdu* snmpPdu;

    // Creates a SNMP session
    _createSession(targetHost, targetHostFormat, portNumber, securityName,
                   sessionHandle, sessionPtr);

    try
    {
        _createPdu(snmpVersion, trapOid, sessionPtr, snmpPdu);
    }
    catch (...)
    {
        _destroySession(sessionHandle);

        PEG_METHOD_EXIT();
        throw;
    }

    // Pack OIDs into the PDU
    try
    {
        _packOidsIntoPdu(vbOids, vbTypes, vbValues, snmpPdu);
    }
    catch (Exception& e)
    {
        Logger::put_l(Logger::STANDARD_LOG, System::CIMSERVER, Logger::WARNING,
            MessageLoaderParms(
                _MSG_PACK_CIM_PROPERTY_TO_PDU_FAILED_KEY,
                _MSG_PACK_CIM_PROPERTY_TO_PDU_FAILED,
                e.getMessage()));
    }
    catch (...)
    {
        PEG_TRACE_CSTRING(TRC_DISCARDED_DATA, Tracer::LEVEL2,
            "Snmp Indication Handler failed to pack a CIM "
                "Property into the SNMP PDU: Unknown exception.");
    }

    // Send the trap to the destination
    if (snmp_sess_send(sessionHandle, snmpPdu) == 0)
    {
        Sint32 libErr, sysErr;
        char* errStr;

        // snmp_sess_send failed
        // get library, system errno
        snmp_sess_error(sessionHandle, &libErr, &sysErr, &errStr);

        String exceptionStr = _MSG_SESSION_SEND_FAILED;
        exceptionStr.append(errStr);

        free(errStr);

        snmp_free_pdu(snmpPdu);

        _destroySession(sessionHandle);

        PEG_METHOD_EXIT();

        throw PEGASUS_CIM_EXCEPTION_L(CIM_ERR_FAILED,
            MessageLoaderParms(_MSG_SESSION_SEND_FAILED_KEY, exceptionStr));
    }

    _destroySession(sessionHandle);

    PEG_METHOD_EXIT();
}

// Creates a SNMP session
void snmpDeliverTrap_netsnmp::_createSession(
    const String& targetHost,
    Uint16 targetHostFormat,
    Uint32 portNumber,
    const String& securityName,
    void*& sessionHandle,
    snmp_session*& sessionPtr)
{
    PEG_METHOD_ENTER(TRC_IND_HANDLER,
        "snmpDeliverTrap_netsnmp::_createSession");

    Sint32 libErr, sysErr;
    char* errStr;
    String exceptionStr;

    struct snmp_session snmpSession;

    {
        AutoMutex autoMut(_sessionInitMutex);
        snmp_sess_init(&snmpSession);

        CString targetHostCStr = targetHost.getCString();

        // peername has format: targetHost:portNumber
        snmpSession.peername =
            (char*)malloc((size_t)(strlen(targetHostCStr) + 1 + 32));

        if (targetHostFormat == _IPV6_ADDRESS)
        {
            sprintf(snmpSession.peername, "udp6:[%s]:%u",
                (const char*)targetHostCStr,
                portNumber);
        }
        else
        {
            sprintf(snmpSession.peername, "%s:%u",
                (const char*)targetHostCStr,
                portNumber);
        }

        sessionHandle = snmp_sess_open(&snmpSession);
    }

    if (sessionHandle == NULL)
    {
        exceptionStr = _MSG_SESSION_OPEN_FAILED;

        // Get library, system errno
        snmp_error(&snmpSession, &libErr, &sysErr, &errStr);

        exceptionStr.append(errStr);

        free(errStr);

        free(snmpSession.peername);

        PEG_METHOD_EXIT();

        throw PEGASUS_CIM_EXCEPTION_L(CIM_ERR_FAILED,
            MessageLoaderParms(_MSG_SESSION_OPEN_FAILED_KEY, exceptionStr));
    }

    try
    {
        // get the snmp_session pointer
        sessionPtr = snmp_sess_session(sessionHandle);
        if (sessionPtr == NULL)
        {
            exceptionStr = _MSG_GET_SESSION_POINT_FAILED;

            // Get library, system errno
            snmp_sess_error(&snmpSession, &libErr, &sysErr, &errStr);

            exceptionStr.append(errStr);

            free(errStr);

            free(snmpSession.peername);

            throw PEGASUS_CIM_EXCEPTION_L(CIM_ERR_FAILED, MessageLoaderParms(
                _MSG_GET_SESSION_POINTER_FAILED_KEY,
                exceptionStr));
        }

        // Community Name, default is public
        String communityName;
        if (securityName.size() == 0)
        {
            communityName.assign("public");
        }
        else
        {
            communityName = securityName;
        }

        free(snmpSession.peername);

        free(sessionPtr->community);

        CString communityNameCStr = communityName.getCString();
        size_t communityNameLen = strlen(communityNameCStr);

        sessionPtr->community = (u_char*)malloc(communityNameLen);

        memcpy(sessionPtr->community, (const char*)communityNameCStr,
               communityNameLen);
        sessionPtr->community_len = communityNameLen;
    }
    catch (...)
    {
        _destroySession(sessionHandle);

        PEG_METHOD_EXIT();
        throw;
    }

    PEG_METHOD_EXIT();
}

// Creates a SNMP session
void snmpDeliverTrap_netsnmp::_destroySession(
    void* sessionHandle)
{
    PEG_METHOD_ENTER(TRC_IND_HANDLER,
        "snmpDeliverTrap_netsnmp::_destroySession");

    snmp_sess_close(sessionHandle);

    PEG_METHOD_EXIT();
}

// Creates a SNMP TRAP PDU
void snmpDeliverTrap_netsnmp::_createPdu(
    Uint16 snmpVersion,
    const String& trapOid,
    snmp_session*& sessionPtr,
    snmp_pdu*& snmpPdu)
{
    PEG_METHOD_ENTER(TRC_IND_HANDLER, "snmpDeliverTrap_netsnmp::_createPdu");

    oid _SYSTEM_UP_TIME_OID [] = {1,3,6,1,2,1,1,3,0};
    oid _SNMPTRAP_OID [] = {1,3,6,1,6,3,1,1,4,1,0};

    in_addr_t* pduInAddr;

    switch (snmpVersion)
    {
        case _SNMPv1_TRAP:
        {

            sessionPtr->version = SNMP_VERSION_1;

            // Create the PDU
            snmpPdu = snmp_pdu_create(SNMP_MSG_TRAP);

            // Failed to create pdu
            if (!snmpPdu)
            {
                PEG_METHOD_EXIT();
                throw PEGASUS_CIM_EXCEPTION_L(CIM_ERR_FAILED,
                    MessageLoaderParms(
                        _MSG_PDU_CREATE_FAILED_KEY,
                        _MSG_PDU_CREATE_FAILED));
            }

            // Make sure that the v1 trap PDU includes the local IP address
            pduInAddr = (in_addr_t*) snmpPdu->agent_addr;
            *pduInAddr = get_myaddr();

            // get system up time
            snmpPdu->time = get_uptime();

            // Pack trap information into the PDU
            try
            {
                _packTrapInfoIntoPdu(trapOid, snmpPdu);
            }
            catch (CIMException& e)
            {
                Logger::put_l(
                    Logger::STANDARD_LOG, System::CIMSERVER, Logger::WARNING,
                    MessageLoaderParms(
                        _MSG_PACK_TRAP_INFO_INTO_PDU_FAILED_KEY,
                        _MSG_PACK_TRAP_INFO_INTO_PDU_FAILED,
                        e.getMessage()));
            }

            break;
        }
        case _SNMPv2C_TRAP:
        {
            sessionPtr->version = SNMP_VERSION_2c;

            // Create the PDU
            snmpPdu = snmp_pdu_create(SNMP_MSG_TRAP2);

            // Failed to create pdu
            if (!snmpPdu)
            {
                PEG_METHOD_EXIT();

                throw PEGASUS_CIM_EXCEPTION_L(CIM_ERR_FAILED,
                    MessageLoaderParms(
                        _MSG_PDU_CREATE_FAILED_KEY,
                        _MSG_PDU_CREATE_FAILED));
            }

            // Add sysUpTime to the PDU
            char sysUpTime[32];
            sprintf(sysUpTime, "%ld", get_uptime());

            Sint32 retCode;
            retCode = snmp_add_var(
                snmpPdu,
                _SYSTEM_UP_TIME_OID,
                OID_LENGTH(_SYSTEM_UP_TIME_OID),
                't',
                sysUpTime);

            // Failed to add sysUpTime to the pdu
            if (retCode != 0)
            {
                String errMsg = snmp_api_errstring(retCode);

                Logger::put_l(
                    Logger::STANDARD_LOG, System::CIMSERVER, Logger::WARNING,
                    MessageLoaderParms(
                        _MSG_ADD_SYSUPTIME_TO_PDU_FAILED_KEY,
                        _MSG_ADD_SYSUPTIME_TO_PDU_FAILED,
                        errMsg));
            }

            // Add snmp trap to the PDU
            retCode = snmp_add_var(
                snmpPdu,
                _SNMPTRAP_OID,
                OID_LENGTH(_SNMPTRAP_OID),
                'o',
                trapOid.getCString());

            // Failed to add snmp trap to the pdu
            if (retCode != 0)
            {
                String errMsg = snmp_api_errstring(retCode);

                Logger::put_l(
                    Logger::STANDARD_LOG, System::CIMSERVER, Logger::WARNING,
                    MessageLoaderParms(
                        _MSG_ADD_SNMP_TRAP_TO_PDU_FAILED_KEY,
                        _MSG_ADD_SNMP_TRAP_TO_PDU_FAILED,
                        errMsg));
            }

            break;
        }
        default:
        {
            PEG_METHOD_EXIT();

            throw PEGASUS_CIM_EXCEPTION_L(CIM_ERR_NOT_SUPPORTED,
                MessageLoaderParms(
                    _MSG_VERSION_NOT_SUPPORTED_KEY,
                    _MSG_VERSION_NOT_SUPPORTED));
        }
    }

    PEG_METHOD_EXIT();
}


// Pack trap information into the PDU
void snmpDeliverTrap_netsnmp::_packTrapInfoIntoPdu(
    const String& trapOid,
    snmp_pdu* snmpPdu)
{
    PEG_METHOD_ENTER(TRC_IND_HANDLER,
        "snmpDeliverTrap_netsnmp::_packTrapInfoIntoPdu");

    oid enterpriseOid[MAX_OID_LEN];
    size_t enterpriseOidLength;

    Array<String> standard_traps;

    standard_traps.append(String("1.3.6.1.6.3.1.1.5.1"));
    standard_traps.append(String("1.3.6.1.6.3.1.1.5.2"));
    standard_traps.append(String("1.3.6.1.6.3.1.1.5.3"));
    standard_traps.append(String("1.3.6.1.6.3.1.1.5.4"));
    standard_traps.append(String("1.3.6.1.6.3.1.1.5.5"));
    standard_traps.append(String("1.3.6.1.6.3.1.1.5.6"));

    Array<const char*> oidSubIdentifiers;

    CString trapOidCStr = trapOid.getCString();

    char* trapOidCopy = strdup(trapOidCStr);
    char* numericEntOid = (char*) malloc(strlen(trapOidCStr));

    try
    {

#if !defined(PEGASUS_OS_TYPE_WINDOWS) && !defined(PEGASUS_OS_ZOS)
        char* last;
        for (const char* p = strtok_r(trapOidCopy, ".", &last); p;
            p=strtok_r(NULL, ".", &last))
#else
        for (const char* p = strtok(trapOidCopy, "."); p; p=strtok(NULL, "."))
#endif
        {
            oidSubIdentifiers.append(p);
        }

        long genTrap = 0;
        long specTrap = 0;

        enterpriseOidLength = MAX_OID_LEN;

        if (Contains(standard_traps, trapOid))
        {
            //
            // if the trapOid is one of the standard traps,
            // then the SNMPV1 enterprise parameter must be set
            // to the value of the trapOid, the generic-trap
            // parameter must be set to one of (0 - 5), and the
            // specific-trap parameter must be set to 0
            //

            // Convert trapOid from numeric form to a list of subidentifiers
            if (read_objid((const char*)trapOidCStr, enterpriseOid,
                &enterpriseOidLength) == 0)
            {
                // Failed to parse trapOid

                PEG_METHOD_EXIT();
                throw PEGASUS_CIM_EXCEPTION_L(CIM_ERR_FAILED,
                    MessageLoaderParms(_MSG_READ_OBJID_FAILED_KEY,
                                       _MSG_READ_OBJID_FAILED,
                                       trapOid));
            }

            // the generic trap is last sub-identifier of the
            // trapOid minus 1
            snmpPdu->trap_type =
                atoi(oidSubIdentifiers[oidSubIdentifiers.size() - 1]) - 1;
            snmpPdu->specific_type = 0;
        }
        else
        {
            //
            // if the trapOid is not one of the standard traps:
            // then 1) the generic-trap parameter must be set to 6,
            // 2) if the next-to-last sub-identifier of the
            // trapOid is zero, then the SNMPV1 enterprise
            // parameter is the trapOid with the last 2
            // sub-identifiers removed, otherwise, the
            // SNMPV1 enterprise parameter is the trapOid
            // with the last sub-identifier removed;
            // 3) the SNMPv1 specific-trap parameter is the last
            // sub-identifier of the trapOid;
            //

            snmpPdu->trap_type = 6;

            snmpPdu->specific_type =
                atoi(oidSubIdentifiers[oidSubIdentifiers.size()-1]);

            strcpy(numericEntOid, oidSubIdentifiers[0]);
            for (Uint32 i = 1; i < oidSubIdentifiers.size()-2; i++)
            {
                strcat(numericEntOid, ".");
                strcat(numericEntOid, oidSubIdentifiers[i]);
            }

            if (strcmp(oidSubIdentifiers[oidSubIdentifiers.size()-2], "0") != 0)
            {
                strcat(numericEntOid, ".");
                strcat(numericEntOid,
                   oidSubIdentifiers[oidSubIdentifiers.size()-2]);
            }

            // Convert ent from numeric form to a list of subidentifiers
            if (read_objid(numericEntOid, enterpriseOid,
                &enterpriseOidLength) == 0)
            {
                // Failed to parse numericEntOid

                PEG_METHOD_EXIT();

                throw PEGASUS_CIM_EXCEPTION_L(CIM_ERR_FAILED,
                    MessageLoaderParms(_MSG_READ_ENTOID_FAILED_KEY,
                                       _MSG_READ_ENTOID_FAILED,
                                       String(numericEntOid)));
            }

        }

        snmpPdu->enterprise = (oid*) malloc(enterpriseOidLength * sizeof(oid));
        memcpy(snmpPdu->enterprise, enterpriseOid,
            enterpriseOidLength * sizeof(oid));

        snmpPdu->enterprise_length = enterpriseOidLength;
    }
    catch (...)
    {
        free(trapOidCopy);
        free(numericEntOid);

        PEG_METHOD_EXIT();
        throw;
    }

    free(trapOidCopy);
    free(numericEntOid);

    PEG_METHOD_EXIT();
}

// Pack oids into the PDU
void snmpDeliverTrap_netsnmp::_packOidsIntoPdu(
    const Array<String>& vbOids,
    const Array<String>& vbTypes,
    const Array<String>& vbValues,
    snmp_pdu* snmpPdu)
{

    PEG_METHOD_ENTER(TRC_IND_HANDLER,
        "snmpDeliverTrap_netsnmp::_packOidsIntoPdu");

    char dataType;
    oid vbOid[MAX_OID_LEN];
    size_t vbOidLength = MAX_OID_LEN;

    for (Uint32 i=0; i < vbOids.size(); i++)
    {
        if (vbTypes[i] == "OctetString")
        {
            dataType = 's';
        }
        else if (vbTypes[i] == "Integer")
        {
            dataType = 'i';
        }
        else if (vbTypes[i] == "OID")
        {
            dataType = 'o';
        }
        else
        {
            // Integer, OctetString, and OID are supported SNMP Data Types
            // for the CIM Property

            PEG_METHOD_EXIT();

            throw PEGASUS_CIM_EXCEPTION_L(CIM_ERR_FAILED,
                MessageLoaderParms(_MSG_UNSUPPORTED_SNMP_DATA_TYPE_KEY,
                                   _MSG_UNSUPPORTED_SNMP_DATA_TYPE,
                                   vbTypes[i]));

        }

        // Convert oid of a CIM property from numeric form to a list of
        // subidentifiers
        if (read_objid((const char*)vbOids[i].getCString(), vbOid,
            &vbOidLength) == 0)
        {
            // Failed to parse vbOids

            PEG_METHOD_EXIT();

            throw PEGASUS_CIM_EXCEPTION_L(CIM_ERR_FAILED,
                MessageLoaderParms(_MSG_PARSE_CIM_PROPERTY_OID_FAILED_KEY,
                                   _MSG_PARSE_CIM_PROPERTY_OID_FAILED,
                                   vbOids[i]));
        }

        Sint32 retCode;
        retCode = snmp_add_var(snmpPdu, vbOid, vbOidLength, dataType,
                               vbValues[i].getCString());

        // Failed to add vbOid to the pdu
        if (retCode != 0)
        {
            PEG_METHOD_EXIT();

            throw PEGASUS_CIM_EXCEPTION_L(CIM_ERR_FAILED,
                MessageLoaderParms(_MSG_ADD_VAR_TO_PDU_FAILED_KEY,
                                   _MSG_ADD_VAR_TO_PDU_FAILED,
                                   vbOids[i],
                                   String(snmp_api_errstring(retCode))));

        }
    }

    PEG_METHOD_EXIT();
}

PEGASUS_NAMESPACE_END