snmp.c

/*
 * Simple Network Management Protocol (RFC 1067).
 *
 */
/**********************************************************************
        Copyright 1988, 1989, 1991, 1992 by Carnegie Mellon University

                      All Rights Reserved

Permission to use, copy, modify, and distribute this software and its 
documentation for any purpose and without fee is hereby granted, 
provided that the above copyright notice appear in all copies and that
both that copyright notice and this permission notice appear in 
supporting documentation, and that the name of CMU not be
used in advertising or publicity pertaining to distribution of the
software without specific, written prior permission.  

CMU DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING
ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO EVENT SHALL
CMU BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR
ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS,
WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION,
ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
SOFTWARE.
******************************************************************/

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

#ifdef KINETICS
#include "gw.h"
#include "ab.h"
#include "inet.h"
#include "fp4/cmdmacro.h"
#include "fp4/pbuf.h"
#include "glob.h"
#endif

#include <stdio.h>
#include <stdlib.h>

#include <sys/types.h>
#ifdef HAVE_STRING_H
#include <string.h>
#else
#include <strings.h>
#endif
#if HAVE_NETINET_IN_H
#include <netinet/in.h>
#endif
#ifdef HAVE_SYS_SELECT_H
#include <sys/select.h>
#endif
#if HAVE_WINSOCK_H
#include <winsock.h>
#endif
#ifndef NULL
#define NULL 0
#endif

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

#ifdef vms
#include <in.h>
#endif

#include <net-snmp/types.h>
#include <net-snmp/output_api.h>

#include <net-snmp/library/asn1.h>
#include <net-snmp/library/snmp.h>      /* for "internal" definitions */
#include <net-snmp/library/snmp_api.h>
#include <net-snmp/library/mib.h>

void
xdump(const u_char * cp, size_t length, const char *prefix)
{
    int             col, count;
    char           *buffer;

    buffer = (char *) malloc(strlen(prefix) + 80);
    if (!buffer) {
        snmp_log(LOG_NOTICE,
                 "xdump: malloc failed. packet-dump skipped\n");
        return;
    }

    count = 0;
    while (count < (int) length) {
        strcpy(buffer, prefix);
        sprintf(buffer + strlen(buffer), "%.4d: ", count);

        for (col = 0; ((count + col) < (int) length) && col < 16; col++) {
            sprintf(buffer + strlen(buffer), "%02X ", cp[count + col]);
            if (col % 4 == 3)
                strcat(buffer, " ");
        }
        for (; col < 16; col++) {       /* pad end of buffer with zeros */
            strcat(buffer, "   ");
            if (col % 4 == 3)
                strcat(buffer, " ");
        }
        strcat(buffer, "  ");
        for (col = 0; ((count + col) < (int) length) && col < 16; col++) {
            buffer[col + 60] =
                isprint(cp[count + col]) ? cp[count + col] : '.';
        }
        buffer[col + 60] = '\n';
        buffer[col + 60 + 1] = 0;
        snmp_log(LOG_DEBUG, "%s", buffer);
        count += col;
    }
    snmp_log(LOG_DEBUG, "\n");
    free(buffer);

}                               /* end xdump() */

/*
 * u_char * snmp_parse_var_op(
 * u_char *data              IN - pointer to the start of object
 * oid *var_name             OUT - object id of variable 
 * int *var_name_len         IN/OUT - length of variable name 
 * u_char *var_val_type      OUT - type of variable (int or octet string) (one byte) 
 * int *var_val_len          OUT - length of variable 
 * u_char **var_val          OUT - pointer to ASN1 encoded value of variable 
 * int *listlength          IN/OUT - number of valid bytes left in var_op_list 
 */

u_char         *
snmp_parse_var_op(u_char * data,
                  oid * var_name,
                  size_t * var_name_len,
                  u_char * var_val_type,
                  size_t * var_val_len,
                  u_char ** var_val, size_t * listlength)
{
    u_char          var_op_type;
    size_t          var_op_len = *listlength;
    u_char         *var_op_start = data;

    data = asn_parse_sequence(data, &var_op_len, &var_op_type,
                              (ASN_SEQUENCE | ASN_CONSTRUCTOR), "var_op");
    if (data == NULL) {
        /*
         * msg detail is set 
         */
        return NULL;
    }
    DEBUGDUMPHEADER("recv", "Name");
    data =
        asn_parse_objid(data, &var_op_len, &var_op_type, var_name,
                        var_name_len);
    DEBUGINDENTLESS();
    if (data == NULL) {
        ERROR_MSG("No OID for variable");
        return NULL;
    }
    if (var_op_type !=
        (u_char) (ASN_UNIVERSAL | ASN_PRIMITIVE | ASN_OBJECT_ID))
        return NULL;
    *var_val = data;            /* save pointer to this object */
    /*
     * find out what type of object this is 
     */
    data = asn_parse_header(data, &var_op_len, var_val_type);
    if (data == NULL) {
        ERROR_MSG("No header for value");
        return NULL;
    }
    /*
     * XXX no check for type! 
     */
    *var_val_len = var_op_len;
    data += var_op_len;
    *listlength -= (int) (data - var_op_start);
    return data;
}

/*
 * u_char * snmp_build_var_op(
 * u_char *data      IN - pointer to the beginning of the output buffer
 * oid *var_name        IN - object id of variable 
 * int *var_name_len    IN - length of object id 
 * u_char var_val_type  IN - type of variable 
 * int    var_val_len   IN - length of variable 
 * u_char *var_val      IN - value of variable 
 * int *listlength      IN/OUT - number of valid bytes left in
 * output buffer 
 */

u_char         *
snmp_build_var_op(u_char * data,
                  oid * var_name,
                  size_t * var_name_len,
                  u_char var_val_type,
                  size_t var_val_len,
                  u_char * var_val, size_t * listlength)
{
    size_t          dummyLen, headerLen;
    u_char         *dataPtr;

    dummyLen = *listlength;
    dataPtr = data;
#if 0
    data = asn_build_sequence(data, &dummyLen,
                              (u_char) (ASN_SEQUENCE | ASN_CONSTRUCTOR),
                              0);
    if (data == NULL) {
        return NULL;
    }
#endif
    if (dummyLen < 4)
        return NULL;
    data += 4;
    dummyLen -= 4;

    headerLen = data - dataPtr;
    *listlength -= headerLen;
    DEBUGDUMPHEADER("send", "Name");
    data = asn_build_objid(data, listlength,
                           (u_char) (ASN_UNIVERSAL | ASN_PRIMITIVE |
                                     ASN_OBJECT_ID), var_name,
                           *var_name_len);
    DEBUGINDENTLESS();
    if (data == NULL) {
        ERROR_MSG("Can't build OID for variable");
        return NULL;
    }
    DEBUGDUMPHEADER("send", "Value");
    switch (var_val_type) {
    case ASN_INTEGER:
        data = asn_build_int(data, listlength, var_val_type,
                             (long *) var_val, var_val_len);
        break;
    case ASN_GAUGE:
    case ASN_COUNTER:
    case ASN_TIMETICKS:
    case ASN_UINTEGER:
        data = asn_build_unsigned_int(data, listlength, var_val_type,
                                      (u_long *) var_val, var_val_len);
        break;
#ifdef OPAQUE_SPECIAL_TYPES
    case ASN_OPAQUE_COUNTER64:
    case ASN_OPAQUE_U64:
#endif
    case ASN_COUNTER64:
        data = asn_build_unsigned_int64(data, listlength, var_val_type,
                                        (struct counter64 *) var_val,
                                        var_val_len);
        break;
    case ASN_OCTET_STR:
    case ASN_IPADDRESS:
    case ASN_OPAQUE:
    case ASN_NSAP:
        data = asn_build_string(data, listlength, var_val_type,
                                var_val, var_val_len);
        break;
    case ASN_OBJECT_ID:
        data = asn_build_objid(data, listlength, var_val_type,
                               (oid *) var_val, var_val_len / sizeof(oid));
        break;
    case ASN_NULL:
        data = asn_build_null(data, listlength, var_val_type);
        break;
    case ASN_BIT_STR:
        data = asn_build_bitstring(data, listlength, var_val_type,
                                   var_val, var_val_len);
        break;
    case SNMP_NOSUCHOBJECT:
    case SNMP_NOSUCHINSTANCE:
    case SNMP_ENDOFMIBVIEW:
        data = asn_build_null(data, listlength, var_val_type);
        break;
#ifdef OPAQUE_SPECIAL_TYPES
    case ASN_OPAQUE_FLOAT:
        data = asn_build_float(data, listlength, var_val_type,
                               (float *) var_val, var_val_len);
        break;
    case ASN_OPAQUE_DOUBLE:
        data = asn_build_double(data, listlength, var_val_type,
                                (double *) var_val, var_val_len);
        break;
    case ASN_OPAQUE_I64:
        data = asn_build_signed_int64(data, listlength, var_val_type,
                                      (struct counter64 *) var_val,
                                      var_val_len);
        break;
#endif                          /* OPAQUE_SPECIAL_TYPES */
    default:
        {
        char error_buf[64];
        snprintf(error_buf, sizeof(error_buf),
                "wrong type in snmp_build_var_op: %d", var_val_type);
        ERROR_MSG(error_buf);
        data = NULL;
        }
    }
    DEBUGINDENTLESS();
    if (data == NULL) {
        return NULL;
    }
    dummyLen = (data - dataPtr) - headerLen;

    asn_build_sequence(dataPtr, &dummyLen,
                       (u_char) (ASN_SEQUENCE | ASN_CONSTRUCTOR),
                       dummyLen);
    return data;
}

#ifdef USE_REVERSE_ASNENCODING
int
snmp_realloc_rbuild_var_op(u_char ** pkt, size_t * pkt_len,
                           size_t * offset, int allow_realloc,
                           const oid * var_name, size_t * var_name_len,
                           u_char var_val_type,
                           u_char * var_val, size_t var_val_len)
{
    size_t          start_offset = *offset;
    int             rc = 0;

    /*
     * Encode the value.  
     */
    DEBUGDUMPHEADER("send", "Value");

    switch (var_val_type) {
    case ASN_INTEGER:
        rc = asn_realloc_rbuild_int(pkt, pkt_len, offset, allow_realloc,
                                    var_val_type, (long *) var_val,
                                    var_val_len);
        break;

    case ASN_GAUGE:
    case ASN_COUNTER:
    case ASN_TIMETICKS:
    case ASN_UINTEGER:
        rc = asn_realloc_rbuild_unsigned_int(pkt, pkt_len, offset,
                                             allow_realloc, var_val_type,
                                             (u_long *) var_val,
                                             var_val_len);
        break;

#ifdef OPAQUE_SPECIAL_TYPES
    case ASN_OPAQUE_COUNTER64:
    case ASN_OPAQUE_U64:
#endif
    case ASN_COUNTER64:
        rc = asn_realloc_rbuild_unsigned_int64(pkt, pkt_len, offset,
                                               allow_realloc, var_val_type,
                                               (struct counter64 *)
                                               var_val, var_val_len);
        break;

    case ASN_OCTET_STR:
    case ASN_IPADDRESS:
    case ASN_OPAQUE:
    case ASN_NSAP:
        rc = asn_realloc_rbuild_string(pkt, pkt_len, offset, allow_realloc,
                                       var_val_type, var_val, var_val_len);
        break;

    case ASN_OBJECT_ID:
        rc = asn_realloc_rbuild_objid(pkt, pkt_len, offset, allow_realloc,
                                      var_val_type, (oid *) var_val,
                                      var_val_len / sizeof(oid));
        break;

    case ASN_NULL:
        rc = asn_realloc_rbuild_null(pkt, pkt_len, offset, allow_realloc,
                                     var_val_type);
        break;

    case ASN_BIT_STR:
        rc = asn_realloc_rbuild_bitstring(pkt, pkt_len, offset,
                                          allow_realloc, var_val_type,
                                          var_val, var_val_len);
        break;

    case SNMP_NOSUCHOBJECT:
    case SNMP_NOSUCHINSTANCE:
    case SNMP_ENDOFMIBVIEW:
        rc = asn_realloc_rbuild_null(pkt, pkt_len, offset, allow_realloc,
                                     var_val_type);
        break;

#ifdef OPAQUE_SPECIAL_TYPES
    case ASN_OPAQUE_FLOAT:
        rc = asn_realloc_rbuild_float(pkt, pkt_len, offset, allow_realloc,
                                      var_val_type, (float *) var_val,
                                      var_val_len);
        break;

    case ASN_OPAQUE_DOUBLE:
        rc = asn_realloc_rbuild_double(pkt, pkt_len, offset, allow_realloc,
                                       var_val_type, (double *) var_val,
                                       var_val_len);
        break;

    case ASN_OPAQUE_I64:
        rc = asn_realloc_rbuild_signed_int64(pkt, pkt_len, offset,
                                             allow_realloc, var_val_type,
                                             (struct counter64 *) var_val,
                                             var_val_len);
        break;
#endif                          /* OPAQUE_SPECIAL_TYPES */
    default:
        {
        char error_buf[64];
        snprintf(error_buf, sizeof(error_buf),
                "wrong type in snmp_realloc_rbuild_var_op: %d", var_val_type);
        ERROR_MSG(error_buf);
        rc = 0;
        }
    }
    DEBUGINDENTLESS();

    if (rc == 0) {
        return 0;
    }

    /*
     * Build the OID.  
     */

    DEBUGDUMPHEADER("send", "Name");
    rc = asn_realloc_rbuild_objid(pkt, pkt_len, offset, allow_realloc,
                                  (u_char) (ASN_UNIVERSAL | ASN_PRIMITIVE |
                                            ASN_OBJECT_ID), var_name,
                                  *var_name_len);
    DEBUGINDENTLESS();
    if (rc == 0) {
        ERROR_MSG("Can't build OID for variable");
        return 0;
    }

    /*
     * Build the sequence header.  
     */

    rc = asn_realloc_rbuild_sequence(pkt, pkt_len, offset, allow_realloc,
                                     (u_char) (ASN_SEQUENCE |
                                               ASN_CONSTRUCTOR),
                                     *offset - start_offset);
    return rc;
}

#endif                          /* USE_REVERSE_ASNENCODING */

---