extend.c

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                                                   extend_free_cache, NULL, 0 );
    if (extension->cache)
        extension->cache->magic = extension;

    row = netsnmp_create_table_data_row();
    if (!row || !extension->cache) {
        _free_extension( extension, ereg );
        SNMP_FREE( row );
        return NULL;
    }
    row->data = (void *)extension;
    extension->row = row;
    netsnmp_table_row_add_index( row, ASN_OCTET_STR,
                                 exec_name, strlen(exec_name));
    if ( netsnmp_table_data_add_row( dinfo, row) != SNMPERR_SUCCESS ) {
        /* _free_extension( extension, ereg ); */
        SNMP_FREE( extension );  /* Probably not sufficient */
        SNMP_FREE( row );
        return NULL;
    }

    ereg->num_entries++;
        /*
         *  Now add this structure to a private linked list.
         *  We don't need this for the main tables - the
         *   'table_data' helper will take care of those.
         *  But it's probably easier to handle the multi-line
         *  output table ourselves, for which we need access
         *  to the underlying data.
         *   So we'll keep a list internally as well.
         */
    for ( eptr1 = ereg->ehead, eptr2 = NULL;
          eptr1;
          eptr2 = eptr1, eptr1 = eptr1->next ) {

        if (strlen( eptr1->token )  > strlen( exec_name ))
            break;
        if (strlen( eptr1->token ) == strlen( exec_name ) &&
            strcmp( eptr1->token, exec_name ) > 0 )
            break;
    }
    if ( eptr2 )
        eptr2->next = extension;
    else
        ereg->ehead = extension;
    extension->next = eptr1;
    return extension;
}

void
extend_parse_config(const char *token, char *cptr)
{
    netsnmp_extend *extension;
    char exec_name[STRMAX];
    char exec_command[STRMAX];
    oid  oid_buf[MAX_OID_LEN];
    size_t oid_len;
    extend_registration_block *eptr;
    int  flags;

    cptr = copy_nword(cptr, exec_name,    sizeof(exec_name));
    if ( *exec_name == '.' ) {
        oid_len = MAX_OID_LEN - 2;
        read_objid( exec_name, oid_buf, &oid_len );
        cptr = copy_nword(cptr, exec_name,    sizeof(exec_name));
        if (!strcmp( token, "sh"   ) ||
            !strcmp( token, "exec" )) {
            config_perror("ERROR: This output format has been deprecated - Please use the 'extend' directive instead" );
            return;
        }
    } else {
        memcpy( oid_buf, ns_extend_oid, sizeof(ns_extend_oid));
        oid_len = OID_LENGTH(ns_extend_oid);
    }
    cptr = copy_nword(cptr, exec_command, sizeof(exec_command));
    /* XXX - check 'exec_command' exists & is executable */
    flags = (NS_EXTEND_FLAGS_ACTIVE | NS_EXTEND_FLAGS_CONFIG);
    if (!strcmp( token, "sh"        ) ||
        !strcmp( token, "extend-sh" ) ||
        !strcmp( token, "sh2" ))
        flags |= NS_EXTEND_FLAGS_SHELL;
    if (!strcmp( token, "execFix"   ) ||
        !strcmp( token, "extendfix" ) ||
        !strcmp( token, "execFix2" )) {
        strcat( exec_name, "Fix" );
        flags |= NS_EXTEND_FLAGS_WRITEABLE;
        /* XXX - Check for shell... */
    }

    eptr      = _register_extend( oid_buf, oid_len );
    extension = _new_extension( exec_name, flags, eptr );
    if (extension) {
        extension->command  = strdup( exec_command );
        if (cptr)
            extension->args = strdup( cptr );
    }

#ifndef USING_UCD_SNMP_EXTENSIBLE_MODULE
    /*
     *  Compatability with the UCD extTable
     */
    if (!strcmp( token, "execFix"  )) {
        int  i;
        for ( i=0; i < num_compatability_entries; i++ ) {
            if (!strcmp( exec_name,
                    compatability_entries[i].exec_entry->token))
                break;
        }
        if ( i == num_compatability_entries )
            config_perror("No matching exec entry" );
        else
            compatability_entries[ i ].efix_entry = extension;
            
    } else if (!strcmp( token, "sh"   ) ||
               !strcmp( token, "exec" )) {
        if ( num_compatability_entries == max_compatability_entries )
            /* XXX - should really use dynamic allocation */
            config_perror("No further UCD-compatible entries" );
        else
            compatability_entries[
                num_compatability_entries++ ].exec_entry = extension;
    }
#endif
}

        /*************************
         *
         *  Main table handlers
         *  Most of the work is handled
         *   by the 'table_data' helper.
         *
         *************************/

int
handle_nsExtendConfigTable(netsnmp_mib_handler          *handler,
                     netsnmp_handler_registration *reginfo,
                     netsnmp_agent_request_info   *reqinfo,
                     netsnmp_request_info         *requests)
{
    netsnmp_request_info       *request;
    netsnmp_table_request_info *table_info;
    netsnmp_extend             *extension;
    extend_registration_block  *eptr;
    int  i;
    int  need_to_validate = 0;

    for ( request=requests; request; request=request->next ) {
        if (request->processed)
            continue;
        table_info = netsnmp_extract_table_info( request );
        extension  = (netsnmp_extend*)netsnmp_extract_table_row_data( request );

        DEBUGMSGTL(( "nsExtendTable:config", "varbind: "));
        DEBUGMSGOID(("nsExtendTable:config", request->requestvb->name,
                                             request->requestvb->name_length));
        DEBUGMSG((   "nsExtendTable:config", " (%s)\n",
                      se_find_label_in_slist("agent_mode", reqinfo->mode)));

        switch (reqinfo->mode) {
        case MODE_GET:
            switch (table_info->colnum) {
            case COLUMN_EXTCFG_COMMAND:
                snmp_set_var_typed_value(
                     request->requestvb, ASN_OCTET_STR,
                     extension->command,
                    (extension->command)?strlen(extension->command):0);
                break;
            case COLUMN_EXTCFG_ARGS:
                snmp_set_var_typed_value(
                     request->requestvb, ASN_OCTET_STR,
                     extension->args,
                    (extension->args)?strlen(extension->args):0);
                break;
            case COLUMN_EXTCFG_INPUT:
                snmp_set_var_typed_value(
                     request->requestvb, ASN_OCTET_STR,
                     extension->input,
                    (extension->input)?strlen(extension->input):0);
                break;
            case COLUMN_EXTCFG_CACHETIME:
                snmp_set_var_typed_value(
                     request->requestvb, ASN_INTEGER,
                    (u_char*)&extension->cache->timeout, sizeof(int));
                break;
            case COLUMN_EXTCFG_EXECTYPE:
                i = ((extension->flags & NS_EXTEND_FLAGS_SHELL) ?
                                         NS_EXTEND_ETYPE_SHELL :
                                         NS_EXTEND_ETYPE_EXEC);
                snmp_set_var_typed_value(
                     request->requestvb, ASN_INTEGER,
                    (u_char*)&i, sizeof(i));
                break;
            case COLUMN_EXTCFG_RUNTYPE:
                i = ((extension->flags & NS_EXTEND_FLAGS_WRITEABLE) ?
                                         NS_EXTEND_RTYPE_RWRITE :
                                         NS_EXTEND_RTYPE_RONLY);
                snmp_set_var_typed_value(
                     request->requestvb, ASN_INTEGER,
                    (u_char*)&i, sizeof(i));
                break;

            case COLUMN_EXTCFG_STORAGE:
                i = ((extension->flags & NS_EXTEND_FLAGS_CONFIG) ?
                                         ST_PERMANENT : ST_VOLATILE);
                snmp_set_var_typed_value(
                     request->requestvb, ASN_INTEGER,
                    (u_char*)&i, sizeof(i));
                break;
            case COLUMN_EXTCFG_STATUS:
                i = ((extension->flags & NS_EXTEND_FLAGS_ACTIVE) ?
                                         RS_ACTIVE :
                                         RS_NOTINSERVICE);
                snmp_set_var_typed_value(
                     request->requestvb, ASN_INTEGER,
                    (u_char*)&i, sizeof(i));
                break;

            default:
                netsnmp_set_request_error(reqinfo, request, SNMP_NOSUCHOBJECT);
                continue;
            }
            break;

        /**********
         *
         * Start of SET handling
         *
         *   All config objects are potentially writable except
         *     nsExtendStorage which is fixed as either 'permanent'
         *     (if read from a config file) or 'volatile' (if set via SNMP)
         *   The string-based settings of a 'permanent' entry cannot 
         *     be changed - neither can the execution or run type.
         *   Such entries can be (temporarily) marked as inactive,
         *     and the cache timeout adjusted, but these changes are
         *     not persistent.
         *
         **********/

        case MODE_SET_RESERVE1:
            /*
             * Validate the new assignments
             */
            switch (table_info->colnum) {
            case COLUMN_EXTCFG_COMMAND:
                if (request->requestvb->type != ASN_OCTET_STR) {
                    netsnmp_set_request_error(reqinfo, request,
                                              SNMP_ERR_WRONGTYPE);
                    return SNMP_ERR_WRONGTYPE;
                }
                /*
                 * Must have a full path to the command
                 * XXX - Assumes Unix-style paths
                 */
                if (request->requestvb->val_len == 0 ||
                    request->requestvb->val.string[0] != '/') {
                    netsnmp_set_request_error(reqinfo, request,
                                              SNMP_ERR_WRONGVALUE);
                    return SNMP_ERR_WRONGVALUE;
                }
                /*
                 * XXX - need to check this file exists
                 *       (and is executable)
                 */

                if (extension && extension->flags & NS_EXTEND_FLAGS_CONFIG) {
                    /*
                     * config entries are "permanent" so can't be changed
                     */
                    netsnmp_set_request_error(reqinfo, request,
                                              SNMP_ERR_NOTWRITABLE);
                    return SNMP_ERR_NOTWRITABLE;
                }
                break;

            case COLUMN_EXTCFG_ARGS:
            case COLUMN_EXTCFG_INPUT:
                if (request->requestvb->type != ASN_OCTET_STR) {
                    netsnmp_set_request_error(reqinfo, request,
                                              SNMP_ERR_WRONGTYPE);
                    return SNMP_ERR_WRONGTYPE;
                }

                if (extension && extension->flags & NS_EXTEND_FLAGS_CONFIG) {
                    /*
                     * config entries are "permanent" so can't be changed
                     */
                    netsnmp_set_request_error(reqinfo, request,
                                              SNMP_ERR_NOTWRITABLE);
                    return SNMP_ERR_NOTWRITABLE;
                }
                break;

            case COLUMN_EXTCFG_CACHETIME:
                if (request->requestvb->type != ASN_INTEGER) {
                    netsnmp_set_request_error(reqinfo, request,
                                              SNMP_ERR_WRONGTYPE);
                    return SNMP_ERR_WRONGTYPE;
                }
                i = *request->requestvb->val.integer;
                /*
                 * -1 is a special value indicating "don't cache"
                 *    [[ XXX - should this be 0 ?? ]]
                 * Otherwise, cache times must be non-negative
                 */
                if (i < -1 ) {
                    netsnmp_set_request_error(reqinfo, request,
                                              SNMP_ERR_WRONGVALUE);
                    return SNMP_ERR_WRONGVALUE;
                }
                break;

            case COLUMN_EXTCFG_EXECTYPE:
                if (request->requestvb->type != ASN_INTEGER) {
                    netsnmp_set_request_error(reqinfo, request,
                                              SNMP_ERR_WRONGTYPE);
                    return SNMP_ERR_WRONGTYPE;
                }
                i = *request->requestvb->val.integer;
                if (i<1 || i>2) {  /* 'exec(1)' or 'shell(2)' only */
                    netsnmp_set_request_error(reqinfo, request,
                                              SNMP_ERR_WRONGVALUE);
                    return SNMP_ERR_WRONGVALUE;
                }
                if (extension && extension->flags & NS_EXTEND_FLAGS_CONFIG) {
                    /*
                     * config entries are "permanent" so can't be changed
                     */
                    netsnmp_set_request_error(reqinfo, request,
                                              SNMP_ERR_NOTWRITABLE);
                    return SNMP_ERR_NOTWRITABLE;
                }
                break;

            case COLUMN_EXTCFG_RUNTYPE:
                if (request->requestvb->type != ASN_INTEGER) {
                    netsnmp_set_request_error(reqinfo, request,
                                              SNMP_ERR_WRONGTYPE);
                    return SNMP_ERR_WRONGTYPE;
                }
                /*
                 * 'run-on-read(1)', 'run-on-set(2)'
                 *  or 'run-command(3)' only
                 */
                i = *request->requestvb->val.integer;
                if (i<1 || i>3) {
                    netsnmp_set_request_error(reqinfo, request,
                                              SNMP_ERR_WRONGVALUE);
                    return SNMP_ERR_WRONGVALUE;
                }
                /*
                 * 'run-command(3)' can only be used with
                 *  a pre-existing 'run-on-set(2)' entry.
                 */
                if (i==3 && !(extension && (extension->flags & NS_EXTEND_FLAGS_WRITEABLE))) {
                    netsnmp_set_request_error(reqinfo, request,
                                              SNMP_ERR_INCONSISTENTVALUE);
                    return SNMP_ERR_INCONSISTENTVALUE;