iftable.c

snmp的源代码,已经在我的ubuntu下编译通过

/*
 *  Interface MIB ifTable (and ifXTable) implementation - ifTable.c
 *
 */

#include <net-snmp/net-snmp-config.h>
#include "mibII_common.h"

#include <net-snmp/net-snmp-includes.h>
#include <net-snmp/agent/net-snmp-agent-includes.h>
#include <net-snmp/agent/auto_nlist.h>
#include <net-snmp/agent/table_container.h>
#include <net-snmp/agent/cache_handler.h>

#include "ifTable.h"
#include "ifTable_columns.h"
#include "ifXTable_columns.h"


/*
 * prototypes for architecture specific routines
 */
void            ifTable_free(netsnmp_cache * cache, void *magic);
int             ifTable_ifentry_info_init(netsnmp_ifentry * entry);
unsigned long long get_ifspeed(netsnmp_ifentry * entry);
int             get_iftype(netsnmp_ifentry * entry);

static int      ifTable_ifentry_compare_name(const void *lhs,
                                             const void *rhs);

/*
 * local statics, or useful utility routines?
 */
netsnmp_ifentry *ifTable_ifentry_get_by_index(netsnmp_cache * cache,
                                              int index);
netsnmp_ifentry *ifTable_ifentry_get_by_name(netsnmp_cache * cache,
                                             char *name, int create);


        /*
         *
         * Initialization and handler routines are common to all architectures
         *
         */
#ifndef MIB_STATS_CACHE_TIMEOUT
#define MIB_STATS_CACHE_TIMEOUT	5
#endif
#ifndef IF_STATS_CACHE_TIMEOUT
#define IF_STATS_CACHE_TIMEOUT	MIB_STATS_CACHE_TIMEOUT
#endif

oid             ifTable_oid[] = { SNMP_OID_MIB2, 2, 2 };
oid             ifXTable_oid[] = { SNMP_OID_MIB2, 31, 1, 1 };

void
init_ifTable(void)
{
    netsnmp_table_registration_info *table_info;
    netsnmp_handler_registration *reginfo;
    netsnmp_container *container;
    netsnmp_cache  *cache;

    DEBUGMSGTL(("mibII/ifTable", "Initialising Interface Table\n"));

     /*
      * get ifcontainer
      */
    container = netsnmp_dal_ifcontainer_init(0);

    /*
     * Create the table data structure, and define the indexing....
     */
    table_info = SNMP_MALLOC_TYPEDEF(netsnmp_table_registration_info);
    if (!table_info) {
        return;
    }
    netsnmp_table_helper_add_indexes(table_info, ASN_INTEGER, 0);
    table_info->min_column = COLUMN_IFINDEX;
    table_info->max_column = COLUMN_IFSPECIFIC;


    /*
     * .... and register the table with the agent.
     */
    reginfo = netsnmp_create_handler_registration("ifTable",
                                                  ifTable_handler,
                                                  ifTable_oid,
                                                  OID_LENGTH(ifTable_oid),
                                                  HANDLER_CAN_RONLY);
    netsnmp_container_table_register(reginfo, table_info, container1,
                                     TABLE_CONTAINER_KEY_NETSNMP_INDEX);

    /*
     * .... with a local cache
     *    (except for Solaris, which uses a different approach)
     */
    cache = netsnmp_cache_create(IF_STATS_CACHE_TIMEOUT,
                                 ifTable_load, ifTable_free,
                                 ifTable_oid, OID_LENGTH(ifTable_oid));
    cache->magic = container1;
    netsnmp_inject_handler(reginfo, netsnmp_cache_handler_get(cache));

#define ENTENDED_IF_TABLE
#ifdef ENTENDED_IF_TABLE
    /*
     * Now do exactly the same thing with the extension table
     */
    DEBUGMSGTL(("mibII/ifTable",
                "Initialising Interface Extension Table\n"));
    table_info = SNMP_MALLOC_TYPEDEF(netsnmp_table_registration_info);
    if (!table_info) {
        return;
    }
    netsnmp_table_helper_add_indexes(table_info, ASN_INTEGER, 0);
    table_info->min_column = COLUMN_IFNAME;
    table_info->max_column = COLUMN_IFCOUNTERDISCONTINUITYTIME;

    reginfo = netsnmp_create_handler_registration("ifXTable",
                                                  ifXTable_handler,
                                                  ifXTable_oid,
                                                  OID_LENGTH(ifXTable_oid),
                                                  HANDLER_CAN_RONLY),
    netsnmp_container_table_register(reginfo, table_info, container1,
                                     TABLE_CONTAINER_KEY_NETSNMP_INDEX);
    netsnmp_inject_handler(reginfo, netsnmp_cache_handler_get(cache));
#endif                          /* ENTENDED_IF_TABLE */
}

NETSNMP_STATIC_INLINE netsnmp_ifentry *
ifTable_ifentry_extract(netsnmp_request_info * request)
{
    return (netsnmp_ifentry *)
        netsnmp_container_table_extract_context(request);
}

static int
ifTable_ifentry_compare_name(const void *lhs, const void *rhs)
{
    return strcmp(((const netsnmp_ifentry *) lhs)->if_name,
                  ((const netsnmp_ifentry *) rhs)->if_name);
}

static void
ifTable_ifentry_release(netsnmp_ifentry * entry, void *context)
{
    if (NULL == entry)
        return;

    if (NULL != entry->if_name)
        free(entry->if_name);

    if (NULL != entry->if_descr)
        free(entry->if_descr);

    free(entry);
}

        /*
         *  Don't actually release the list
         *  (since it contains static information)
         *  Just mark the entries as inactive.
         */
void
ifTable_free(netsnmp_cache * cache, void *magic)
{
    netsnmp_container *container;

    if ((NULL == cache) || (NULL == cache->magic)) {
        snmp_log(LOG_ERR, "invalid cache for ifTable\n");
        return;
    }
    DEBUGMSGTL(("ifTable/cache", "ifTable_free %p/%p\n",
                cache, cache->magic));

    container = (netsnmp_container *) cache->magic;

    /*
     * free all items. inefficient, but easy.
     */
    CONTAINER_CLEAR(container, ifTable_ifentry_release, NULL);


}

        /************
	 *
 	 *  Handler for the original ifTable
 	 *
	 ************/

int
ifTable_handler(netsnmp_mib_handler * handler,
                netsnmp_handler_registration * reginfo,
                netsnmp_agent_request_info * reqinfo,
                netsnmp_request_info * requests)
{
    netsnmp_request_info *request;
    netsnmp_variable_list *requestvb;
    netsnmp_table_request_info *table_info;
    netsnmp_ifentry *entry;
    oid             subid;
    long            val;

    DEBUGMSGTL(("mibII/ifTable", "Handler - mode %s\n",
                se_find_label_in_slist("agent_mode", reqinfo->mode)));
    switch (reqinfo->mode) {
    case MODE_GET:
        for (request = requests; request; request = request->next) {
            requestvb = request->requestvb;
            DEBUGMSGTL(("mibII/ifTable", "oid: "));
            DEBUGMSGOID(("mibII/ifTable", requestvb->name,
                         requestvb->name_length));
            DEBUGMSG(("mibII/ifTable", "\n"));

            entry = ifTable_ifentry_extract(request);
            if (!entry)
                continue;
            table_info = netsnmp_extract_table_info(request);
            subid = table_info->colnum;

            switch (subid) {
            case COLUMN_IFINDEX:
                snmp_set_var_typed_value(requestvb, ASN_INTEGER,
                                         (u_char *) & entry->index,
                                         sizeof(entry->index));
                break;
            case COLUMN_IFDESCR:
                snmp_set_var_typed_value(requestvb, ASN_OCTET_STR,
                                         (u_char *) entry->if_descr,
                                         (entry->if_descr ?
                                          strlen(entry->if_descr) : 0));
                break;
            case COLUMN_IFTYPE:
                snmp_set_var_typed_value(requestvb, ASN_INTEGER,
                                         (u_char *) & entry->if_type,
                                         sizeof(entry->if_type));
                break;
            case COLUMN_IFMTU:
                snmp_set_var_typed_value(requestvb, ASN_INTEGER,
                                         (u_char *) & entry->if_mtu,
                                         sizeof(entry->if_mtu));
                break;
            case COLUMN_IFSPEED:
                if (entry->flags & NETSNMP_IF_FLAGS_DYNAMIC_SPEED)
                    val = get_ifspeed(entry) & 0xffffffff;
                else
                    val = entry->if_speed;
                snmp_set_var_typed_value(requestvb, ASN_GAUGE,
                                         (u_char *) & val, sizeof(val));
                break;
            case COLUMN_IFPHYSADDRESS:
                snmp_set_var_typed_value(requestvb, ASN_OCTET_STR,
                                         (u_char *) entry->if_paddr,
                                         entry->if_paddr_len);
                break;
            case COLUMN_IFADMINSTATUS:
            case COLUMN_IFOPERSTATUS:
                /*
                 * XXX 
                 */
                netsnmp_set_request_error(reqinfo, request,
                                          SNMP_NOSUCHOBJECT);
                break;
            case COLUMN_IFLASTCHANGE:
                if (entry->flags & NETSNMP_IF_FLAGS_HAS_LASTCHANGE)
                    snmp_set_var_typed_value(requestvb, ASN_INTEGER,
                                             (u_char *) & entry->
                                             if_lastchange,
                                             sizeof(entry->if_lastchange));
                else
                    netsnmp_set_request_error(reqinfo, request,
                                              SNMP_NOSUCHINSTANCE);
                break;
            case COLUMN_IFINOCTETS:
                if (entry->flags & NETSNMP_IF_FLAGS_HAS_BYTES)
                    snmp_set_var_typed_value(requestvb, ASN_COUNTER,
                                             (u_char *) & entry->if_ibytes.
                                             low,
                                             sizeof(entry->if_ibytes.low));
                else
                    netsnmp_set_request_error(reqinfo, request,
                                              SNMP_NOSUCHINSTANCE);
                break;
            case COLUMN_IFINUCASTPKTS:
                snmp_set_var_typed_value(requestvb, ASN_COUNTER,
                                         (u_char *) & entry->if_iucast.low,
                                         sizeof(entry->if_iucast.low));
                break;
            case COLUMN_IFINNUCASTPKTS:
                /*
                 * Deprecated object 
                 */
                val = entry->if_imcast.low + entry->if_ibcast.low;
                snmp_set_var_typed_value(requestvb, ASN_COUNTER,
                                         (u_char *) & val, sizeof(val));
                break;
            case COLUMN_IFINDISCARDS:
                snmp_set_var_typed_value(requestvb, ASN_COUNTER,
                                         (u_char *) & entry->if_idiscards,
                                         sizeof(entry->if_idiscards));