namingscopes.c

wm PNE 3.3 source code, running at more than vxworks6.x version.

/* namingScopes.c - register naming scopes functions */

/*
 *  Copyright 2002-2005 Wind River Systems, Inc.
 *  All rights reserved.  Provided under license only.
 *  Distribution or other use of this software is only
 *  permitted pursuant to the terms of a license agreement
 *  from Wind River Systems (and is otherwise prohibited).
 *  Refer to that license agreement for terms of use.
 */

#include "copyright_wrs.h"

/*
modification history
-------------------
01e,19apr05,job  update copyright notices
01d,01dec03,job  update copyright information
01c,12mar03,ant  changes after code review, changed component name
01b,17jan02,ism  code clean up
01a,05dec02,ism  written
*/

#include <wrn/wm/snmp/engine/asn1conf.h>
#include <wrn/wm/snmp/engine/snmp.h>
#include <wrn/wm/snmp/engine/asn1.h>
#include <wrn/wm/snmp/engine/buffer.h>
#include <wrn/wm/snmp/vxagent/namingScopes.h>

#if INSTALL_SNMP_VXWORKS_VIRTUAL_STACK

/* defines */

/* Defines used for listType */

#define COMMUNITY_LIST   0x01 /* used for SNMPv1 and v2 */
#define CONTEXT_LIST     0x02 /* used for SNMPv3 */

/* debug define, used for testing */

#ifndef NAMING_SCOPE_DEBUG
#define NAMING_SCOPE_DEBUG 0
#endif 

/* types */

typedef struct VIEW_LIST_S
    {
    struct VIEW_LIST_S * next;
    EBUFFER_T            commOrCon; /* either a community or a context */
    bits8_t              viewType;  /* get, set or get/set */
    EBUFFER_T            viewName;  /* RFC 2275 view name */
    bits32_t             vsNum;     /* Virtual Stack number */
    } VIEW_LIST_T;

typedef struct VIEW_LIST_HEAD_S
    {
    struct VIEW_LIST_S * first;
    bits8_t              listType; /* either COMMUNITY_LIST or CONTEXT_LIST */
    } VIEW_LIST_HEAD_T;

/* statics */

LOCAL VIEW_LIST_HEAD_T   communityStringHead;
LOCAL VIEW_LIST_T *      communityStringLastMatch = NULL;

#if INSTALL_ENVOY_SNMP_VERSION_3
LOCAL VIEW_LIST_HEAD_T   contextNameHead;
LOCAL VIEW_LIST_T *      contextNameLastMatch = NULL;
#endif /* INSTALL_ENVOY_SNMP_VERSION_3 */

/* local functions that do all the work */

/******************************************************************************
 *
 * viewRegisterIntern - Internal function to register a view
 *
 * This function adds a new view, or viewType, to the list whose head is
 * <viewListHead>, which will be either the list for community strings or
 * context names.
 *
 * Note that if multi-instance is not installed then <vsNum> will be ignored.
 *
 * Parameters:
 *
 * <viewListHead>       - head of view list
 * <commOrCon>          - either community or context
 * <stringLen>          - the length of <commOrCon>
 * <viewType>           - type of view, get, set, get/set
 * <viewName>           - view name for this view
 * <nameLen>            - the length of <viewName>
 * <vsNum>              - the vsnum for the new view
 *
 * RETURNS: OK or ERROR
 *
 */

LOCAL STATUS viewRegisterIntern
    (
    VIEW_LIST_HEAD_T * viewListHead,
    bits8_t *          commOrCon,
    bits32_t           stringLen,
    bits8_t            viewType,
    bits8_t *          viewName,
    bits32_t           nameLen,
    bits32_t           vsNum
    )
    {
    VIEW_LIST_T * newEntry = NULL, * current;

    if ((commOrCon == NULL) || 
        ((viewType & (VIEW_TYPE_GET | VIEW_TYPE_SET)) == 0))
        {
#if NAMING_SCOPE_DEBUG
        printf ("Invalid argument(s): Name: %s Name Length: %d Type: %d\n",
                commOrCon, stringLen, viewType);
#endif /* NAMING_SCOPE_DEBUG */

        return (ERROR);
        }

    /*
     * search for this view in our list of already registered views, starting
     * at <viewListHead>. If we find one then allow the viewType to be changed
     * if the other attributes are the same, so we don't add a contradicting
     * view entry, otherwise return ERROR.
     */
    for (current = viewListHead->first; current != NULL;
         current = current->next)
        {
        if ((stringLen == EBufferUsed (&current->commOrCon)) &&
            (memcmp (commOrCon,
                     EBufferStart (&current->commOrCon),
                     stringLen) == 0))
            {
            /* 
             * Found existing view, check attributes.
             */
            if ((nameLen == EBufferUsed (&current->viewName)) &&
                (memcmp (viewName,
                         EBufferStart (&current->viewName),
                         nameLen) == 0)
                && (current->vsNum == vsNum)
                )
                {
#if NAMING_SCOPE_DEBUG
                printf ("Found existing entry, adding viewType\n");
#endif /* NAMING_SCOPE_DEBUG */

                /*
                 * found existing view, update viewType. This will not
                 * remove the existing view type but will either add another
                 * view type for this entry or have no effect if the existing
                 * view type is the same as the new view type.
                 */
                current->viewType |= viewType;

                return (OK);
                }
                else
                {
                /* found existing view but with different attributes */
                return (ERROR);
                }
            }
        }

    /* view doesn't already exist, add a new one */

#if NAMING_SCOPE_DEBUG
    printf ("Adding new entry\n");
#endif /* NAMING_SCOPE_DEBUG */

    if ((newEntry = (VIEW_LIST_T *) 
            SNMP_memory_alloc (sizeof (VIEW_LIST_T))) == 0)
        {
        return (ERROR);
        }

    EBufferInitialize (&newEntry->commOrCon);

    if ((EBufferAllocateLoad (BFL_IS_ALLOC, &newEntry->commOrCon,
                              commOrCon, stringLen)) != 0)
        {
        SNMP_memory_free (newEntry);
        return (ERROR);
        }

    newEntry->viewType = viewType;

    EBufferInitialize (&newEntry->viewName);

    if ((EBufferAllocateLoad (BFL_IS_ALLOC, &newEntry->viewName,
                              viewName, nameLen)) != 0)
        {
        EBufferClean (&newEntry->commOrCon);
        SNMP_memory_free (newEntry);
        return (ERROR);
        }

    newEntry->vsNum = vsNum;

    /* link newEntry into list */

#if NAMING_SCOPE_DEBUG
    printf ("Linking into list... First: %p New entry: %p\n", 
               viewListHead->first, newEntry);
#endif /* NAMING_SCOPE_DEBUG */

    newEntry->next = viewListHead->first;
    viewListHead->first = newEntry;

#if NAMING_SCOPE_DEBUG
    printf ("Done! First: %p New entry->next %p\n", viewListHead->first,
                                                    newEntry->next);
#endif /* NAMING_SCOPE_DEBUG */

    return (OK);
    }

/******************************************************************************
 *
 * viewDeregisterIntern - Internal funtcion to deregister a view
 *
 * This function removes a view, or viewType, from the list whose head is
 * <viewListHead>, which will either be the list for community strings or
 * context names.
 *
 * Note that if multi-instance is not installed then <vsNum> will be ignored.
 *
 * Parameters:
 *
 * <viewListHead>    - head of view list
 * <commOrCon>       - either community or context
 * <stringLen>       - the length of <commOrCon>
 * <viewType>        - type of view to deregister, get, set, get/set
 * <vsNum>           - the vsnum associated with <communityString>
 *
 * RETURNS: OK or ERROR
 *
 */

LOCAL STATUS viewDeregisterIntern
    (
    VIEW_LIST_HEAD_T * viewListHead,
    bits8_t *          commOrCon,
    bits32_t           stringLen,
    bits8_t            viewType,
    bits32_t           vsNum
    )
    {
    VIEW_LIST_T * current, * previous = NULL, ** lastMatch;

    if (viewListHead->listType == COMMUNITY_LIST)
        lastMatch = &communityStringLastMatch;
#if INSTALL_ENVOY_SNMP_VERSION_3
    else if (viewListHead->listType == CONTEXT_LIST)
        lastMatch = &contextNameLastMatch;
#endif /* INSTALL_ENVOY_SNMP_VERSION_3 */
    else
        {
        /* viewListHead not initialised! */

#if NAMING_SCOPE_DEBUG
        printf ("\nUnknown list type!\n");
#endif /* NAMING_SCOPE_DEBUG */

        return (ERROR);
        }

    if (commOrCon != NULL)
        {
#if NAMING_SCOPE_DEBUG
        printf ("Attempting to remove %s\n", commOrCon);
#endif /* NAMING_SCOPE_DEBUG */

        /* remove view that matches commOrCon */

        for (current = viewListHead->first; current != NULL;
             current = current->next)
            {
            if ((stringLen == EBufferUsed (&current->commOrCon)) &&
                (memcmp (commOrCon,
                         EBufferStart (&current->commOrCon),
                         stringLen) == 0))
                {
                /* found view */
                current->viewType &= ~viewType;

                if (current->viewType != 0)
                    {
#if NAMING_SCOPE_DEBUG
                    printf ("Only removing view type %d from %s\n",
                            viewType, commOrCon);
#endif /* NAMING_SCOPE_DEBUG */
                    /*
                     * only deregister the type specified by viewType, this
                     * commOrCon string is also used for other view types so 
                     * don't remove the entry.
                     */
                    return (OK);
                    }

                if (previous == NULL)
                    viewListHead->first = current->next;
                else
                    previous->next = current->next;

#if NAMING_SCOPE_DEBUG
                printf ("Removed %s view\n", commOrCon);
#endif /* NAMING_SCOPE_DEBUG */

                if (current == *lastMatch)
                    *lastMatch = NULL;

                EBufferClean (&current->viewName);
                EBufferClean (&current->commOrCon);
                SNMP_memory_free (current);
                return (OK);
                }
            previous = current;
            }

        /* view not found, return ERROR */

#if NAMING_SCOPE_DEBUG
        printf ("%s view not found!\n", commOrCon);
#endif /* NAMING_SCOPE_DEBUG */

        return (ERROR);
        }

    else /* commOrCon == NULL */
        {
        /* remove all views for VS vsNum */

        VIEW_LIST_T * currentNext;

#if NAMING_SCOPE_DEBUG
        printf ("Attempting to remove all views for VS%d\n", vsNum);
#endif /* NAMING_SCOPE_DEBUG */

        for (current = viewListHead->first; current != NULL;
             current = currentNext)
            {
            if (current->vsNum == vsNum)
                {
                /* found view for VS vsNum */

#if NAMING_SCOPE_DEBUG
                char * tmpViewString;