pass.c

snmp的源代码,已经在我的ubuntu下编译通过

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

#if HAVE_STDLIB_H
#include <stdlib.h>
#endif
#include <stdio.h>
#if HAVE_STRING_H
#include <string.h>
#else
#include <strings.h>
#endif
#if HAVE_UNISTD_H
#include <unistd.h>
#endif
#include <ctype.h>
#include <sys/types.h>
#if HAVE_NETINET_IN_H
#include <netinet/in.h>
#endif
#if HAVE_SYS_WAIT_H
# include <sys/wait.h>
#endif
#if HAVE_WINSOCK_H
#include <winsock.h>
#endif

#if HAVE_DMALLOC_H
#include <dmalloc.h>
#endif

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

#include "struct.h"
#include "pass.h"
#include "extensible.h"
#include "util_funcs.h"

struct extensible *passthrus = NULL;
int             numpassthrus = 0;

/*
 * the relocatable extensible commands variables 
 */
struct variable2 extensible_passthru_variables[] = {
    /*
     * bogus entry.  Only some of it is actually used. 
     */
    {MIBINDEX, ASN_INTEGER, RWRITE, var_extensible_pass, 0, {MIBINDEX}},
};



/*
 * lexicographical compare two object identifiers.
 * * Returns -1 if name1 < name2,
 * *          0 if name1 = name2,
 * *          1 if name1 > name2
 * *
 * * This method differs from snmp_oid_compare
 * * in that the comparison stops at the length
 * * of the smallest object identifier.
 */
int
snmp_oid_min_compare(const oid * in_name1,
                     size_t len1, const oid * in_name2, size_t len2)
{
    register int    len;
    register const oid *name1 = in_name1;
    register const oid *name2 = in_name2;

    /*
     * len = minimum of len1 and len2 
     */
    if (len1 < len2)
        len = len1;
    else
        len = len2;
    /*
     * find first non-matching OID 
     */
    while (len-- > 0) {
        /*
         * these must be done in seperate comparisons, since
         * subtracting them and using that result has problems with
         * subids > 2^31. 
         */
        if (*(name1) < *(name2))
            return -1;
        if (*(name1++) > *(name2++))
            return 1;
    }
    /*
     * both OIDs equal up to length of shorter OID 
     */

    return 0;
}


/*
 * This is also called from pass_persist.c 
 */
int
asc2bin(char *p)
{
    char           *r, *q = p;
    char            c;
    int             n = 0;

    for (;;) {
        c = (char) strtol(q, &r, 16);
        if (r == q)
            break;
        *p++ = c;
        q = r;
        n++;
    }
    return n;
}

/*
 * This is also called from pass_persist.c 
 */
int
bin2asc(char *p, size_t n)
{
    int             i, flag = 0;
    char            buffer[SNMP_MAXBUF];

    /* prevent buffer overflow */
    if ((int)n > (sizeof(buffer) - 1))
        n = sizeof(buffer) - 1;

    for (i = 0; i < (int) n; i++) {
        buffer[i] = p[i];
        if (!isprint(p[i]))
            flag = 1;
    }
    if (flag == 0) {
        p[n] = 0;
        return n;
    }
    for (i = 0; i < (int) n; i++) {
        sprintf(p, "%02x ", (unsigned char) (buffer[i] & 0xff));
        p += 3;
    }
    *--p = 0;
    return 3 * n - 1;
}

void
init_pass(void)
{
    snmpd_register_config_handler("pass", pass_parse_config,
                                  pass_free_config, "miboid command");
}

void
pass_parse_config(const char *token, char *cptr)
{
    struct extensible **ppass = &passthrus, **etmp, *ptmp;
    char           *tcptr;
    int             i;

    if (*cptr == '.')
        cptr++;
    if (!isdigit(*cptr)) {
        config_perror("second token is not a OID");
        return;
    }
    numpassthrus++;

    while (*ppass != NULL)
        ppass = &((*ppass)->next);
    (*ppass) = (struct extensible *) malloc(sizeof(struct extensible));
    if (*ppass == NULL)
        return;
    (*ppass)->type = PASSTHRU;

    (*ppass)->miblen = parse_miboid(cptr, (*ppass)->miboid);
    while (isdigit(*cptr) || *cptr == '.')
        cptr++;
    /*
     * name 
     */
    cptr = skip_white(cptr);
    if (cptr == NULL) {
        config_perror("No command specified on pass line");
        (*ppass)->command[0] = 0;
    } else {
        for (tcptr = cptr; *tcptr != 0 && *tcptr != '#' && *tcptr != ';';
             tcptr++);
        strncpy((*ppass)->command, cptr, tcptr - cptr);
        (*ppass)->command[tcptr - cptr] = 0;
    }
    strncpy((*ppass)->name, (*ppass)->command, sizeof((*ppass)->name));
    (*ppass)->name[ sizeof((*ppass)->name)-1 ] = 0;
    (*ppass)->next = NULL;

    register_mib("pass", (struct variable *) extensible_passthru_variables,
                 sizeof(struct variable2),
                 1, (*ppass)->miboid, (*ppass)->miblen);

    /*
     * argggg -- pasthrus must be sorted 
     */
    if (numpassthrus > 1) {
        etmp = (struct extensible **)
            malloc(((sizeof(struct extensible *)) * numpassthrus));
        if (etmp == NULL)
            return;

        for (i = 0, ptmp = (struct extensible *) passthrus;
             i < numpassthrus && ptmp != 0; i++, ptmp = ptmp->next)
            etmp[i] = ptmp;
        qsort(etmp, numpassthrus, sizeof(struct extensible *),
              pass_compare);
        passthrus = (struct extensible *) etmp[0];
        ptmp = (struct extensible *) etmp[0];

        for (i = 0; i < numpassthrus - 1; i++) {
            ptmp->next = etmp[i + 1];
            ptmp = ptmp->next;
        }
        ptmp->next = NULL;
        free(etmp);
    }
}

void
pass_free_config(void)
{
    struct extensible *etmp, *etmp2;

    for (etmp = passthrus; etmp != NULL;) {
        etmp2 = etmp;
        etmp = etmp->next;
        unregister_mib(etmp2->miboid, etmp2->miblen);
        free(etmp2);
    }
    passthrus = NULL;
    numpassthrus = 0;
}

u_char         *
var_extensible_pass(struct variable *vp,
                    oid * name,
                    size_t * length,
                    int exact,
                    size_t * var_len, WriteMethod ** write_method)
{
    oid             newname[MAX_OID_LEN];
    int             i, rtest, fd, newlen;