agent/snmp_agent.c - vendor/opensource/netsnmp - Git at Google

 /*
  * snmp_agent.c
  *
  * Simple Network Management Protocol (RFC 1067).
  */
 /***********************************************************
 	Copyright 1988, 1989 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 <config.h>

 #include <sys/types.h>
 #ifdef HAVE_STDLIB_H
 #include <stdlib.h>
 #endif
 #if HAVE_UNISTD_H
 #include <unistd.h>
 #endif
 #if HAVE_STRING_H
 #include <string.h>
 #endif
 #if TIME_WITH_SYS_TIME
 # ifdef WIN32
 #  include <sys/timeb.h>
 # else
 #  include <sys/time.h>
 # endif
 # include <time.h>
 #else
 # if HAVE_SYS_TIME_H
 #  include <sys/time.h>
 # else
 #  include <time.h>
 # endif
 #endif
 #if HAVE_SYS_SELECT_H
 #include <sys/select.h>
 #endif
 #if HAVE_NETINET_IN_H
 #include <netinet/in.h>
 #endif
 #include <errno.h>
 #if HAVE_WINSOCK_H
 #include <winsock.h>
 #endif

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

 #include "asn1.h"
 #define SNMP_NEED_REQUEST_LIST
 #include "snmp_api.h"
 #include "snmp_impl.h"
 #include "snmp.h"
 #include "mib.h"
 #include "snmp_client.h"

 #include "snmp_vars.h"
 #include "snmpd.h"
 #include "mibgroup/struct.h"
 #include "mibgroup/util_funcs.h"
 #include "var_struct.h"
 #include "read_config.h"
 #include "snmp_logging.h"
 #include "snmp_debug.h"
 #include "mib_module_config.h"

 #include "default_store.h"
 #include "ds_agent.h"
 #include "snmp_agent.h"
 #include "agent_trap.h"

 static int snmp_vars_inc;

 static struct agent_snmp_session *agent_session_list = NULL;


 static void dump_var(oid *, size_t, int, void *, size_t);
 static int goodValue(u_char, size_t, u_char, size_t);
 static void setVariable(u_char *, u_char, size_t, u_char *, size_t);

 static void dump_var (
     oid *var_name,
     size_t var_name_len,
     int statType,
     void *statP,
     size_t statLen)
 {
     char buf [SPRINT_MAX_LEN];
     struct variable_list temp_var;

     temp_var.type = statType;
     temp_var.val.string = (u_char *)statP;
     temp_var.val_len = statLen;
     sprint_variable (buf, var_name, var_name_len, &temp_var);
     snmp_log(LOG_INFO, "    >> %s\n", buf);
 }


 int getNextSessID()
 {
     static int SessionID = 0;

     return ++SessionID;
 }

 int
 agent_check_and_process(int block) {
   int numfds;
   fd_set fdset;
   struct timeval	timeout, *tvp = &timeout;
   int count;
   int fakeblock=0;

   tvp =  &timeout;

   numfds = 0;
   FD_ZERO(&fdset);
   snmp_select_info(&numfds, &fdset, tvp, &fakeblock);
   if (block == 1 && fakeblock == 1)
     tvp = NULL; /* block without timeout */
   else if (block == 0) {
       tvp->tv_sec = 0;
       tvp->tv_usec = 0;
   }

   count = select(numfds, &fdset, 0, 0, tvp);

   if (count > 0){
     /* packets found, process them */
     snmp_read(&fdset);
   } else switch(count){
     case 0:
       snmp_timeout();
       break;
     case -1:
       if (errno == EINTR){
         return -1;
       } else {
         snmp_log_perror("select");
       }
       return -1;
     default:
       snmp_log(LOG_ERR, "select returned %d\n", count);
       return -1;
   }  /* endif -- count>0 */
   return count;
 }


 /*
  * The session is created using the "traditional API" routine snmp_open()
  * so is linked into the global library Sessions list.  It also opens a
  * socket that listens for incoming requests.
  *
  *   The agent runs in an infinite loop (in the 'receive()' routine),
  * which calls snmp_read() when such a request is received on this socket.
  * This routine then traverses the library 'Sessions' list to identify the
  * relevant session and eventually invokes '_sess_read'.
  *   This then processes the incoming packet, calling the pre_parse, parse,
  * post_parse and callback routines in turn.
  */

 	/* Global access to the primary session structure for this agent.
 		for Index Allocation use initially. */
 struct snmp_session *main_session;

 void
 init_master_agent(int dest_port,
                   int (*pre_parse) (struct snmp_session *, snmp_ipaddr),
                   int (*post_parse) (struct snmp_session *, struct snmp_pdu *,int))
 {
     struct snmp_session sess, *session;

     if ( ds_get_boolean(DS_APPLICATION_ID, DS_AGENT_ROLE) != MASTER_AGENT )
 	return;

     DEBUGMSGTL(("snmpd","installing master agent on port %d", dest_port));

     snmp_sess_init( &sess );

     sess.version = SNMP_DEFAULT_VERSION;
     sess.peername = SNMP_DEFAULT_PEERNAME;
     sess.community_len = SNMP_DEFAULT_COMMUNITY_LEN;

     sess.local_port = dest_port;
     sess.callback = handle_snmp_packet;
     sess.authenticator = NULL;
     sess.flags = ds_get_int(DS_APPLICATION_ID, DS_AGENT_FLAGS);
     session = snmp_open_ex( &sess, pre_parse, 0, post_parse, 0, 0 );

     if ( session == NULL ) {
       /* diagnose snmp_open errors with the input struct snmp_session pointer */
 	snmp_sess_perror("init_master_agent", &sess);
 	exit(1);
     }
     main_session = session;
 }

 struct agent_snmp_session  *
 init_agent_snmp_session( struct snmp_session *session, struct snmp_pdu *pdu )
 {
     struct agent_snmp_session  *asp;

     asp = malloc( sizeof( struct agent_snmp_session ));
     if ( asp == NULL )
 	return NULL;
     asp->start = pdu->variables;
     asp->end   = pdu->variables;
     if ( asp->end != NULL )
 	while ( asp->end->next_variable != NULL )
 	    asp->end = asp->end->next_variable;
     asp->session = session;
     asp->pdu     = pdu;
     asp->rw      = READ;
     asp->exact   = TRUE;
     asp->outstanding_requests = NULL;
     asp->next    = NULL;
     asp->mode    = RESERVE1;
     asp->status  = SNMP_ERR_NOERROR;

     return asp;
 }

 int
 count_varbinds( struct snmp_pdu *pdu )
 {
   int count = 0;
   struct variable_list *var_ptr;

   for ( var_ptr = pdu->variables ; var_ptr != NULL ;
 		  	var_ptr = var_ptr->next_variable )
 	count++;

   return count;
 }

 int
 handle_snmp_packet(int operation, struct snmp_session *session, int reqid,
                    struct snmp_pdu *pdu, void *magic)
 {
     struct agent_snmp_session  *asp;
     int status, allDone, i;
     struct variable_list *var_ptr, *var_ptr2;

     if ( magic == NULL ) {
 	asp = init_agent_snmp_session( session, snmp_clone_pdu(pdu) );
 	status = SNMP_ERR_NOERROR;
     }
     else {
 	asp = (struct agent_snmp_session *)magic;
         status =   asp->status;
     }

     if (asp->outstanding_requests != NULL)
 	return 1;

     switch (pdu->command) {
     case SNMP_MSG_GET:
 	if ( asp->mode != RESERVE1 )
 	    break;			/* Single pass */
         snmp_increment_statistic(STAT_SNMPINGETREQUESTS);
 	status = handle_next_pass( asp );
 	asp->mode = RESERVE2;
 	break;

     case SNMP_MSG_GETNEXT:
 	if ( asp->mode != RESERVE1 )
 	    break;			/* Single pass */
         snmp_increment_statistic(STAT_SNMPINGETNEXTS);
 	asp->exact   = FALSE;
 	status = handle_next_pass( asp );
 	asp->mode = RESERVE2;
 	break;

     case SNMP_MSG_GETBULK:
 	    /*
 	     * GETBULKS require multiple passes. The first pass handles the
 	     * explicitly requested varbinds, and subsequent passes append
 	     * to the existing var_op_list.  Each pass (after the first)
 	     * uses the results of the preceeding pass as the input list
 	     * (delimited by the start & end pointers.
 	     * Processing is terminated if all entries in a pass are
 	     * EndOfMib, or the maximum number of repetitions are made.
 	     */
 	if ( asp->mode == RESERVE1 ) {
             snmp_increment_statistic(STAT_SNMPINGETREQUESTS);
 	    asp->exact   = FALSE;
 		    /*
 		     * Limit max repetitions to something reasonable
 		     *	XXX: We should figure out what will fit somehow...
 		     */
 	    if ( asp->pdu->errindex > 100 )
 	        asp->pdu->errindex = 100;

 	    status = handle_next_pass( asp );	/* First pass */
 	    asp->mode = RESERVE2;
 	    if ( status != SNMP_ERR_NOERROR )
 	        break;

 	    while ( asp->pdu->errstat-- > 0 )	/* Skip non-repeaters */
 	        asp->start = asp->start->next_variable;
 	    asp->pdu->errindex--;           /* Handled first repetition */

 	    if ( asp->outstanding_requests != NULL )
 		return 1;
 	}

 	while ( asp->pdu->errindex-- > 0 ) {	/* Process repeaters */
 		/*
 		 * Add new variable structures for the
 		 * repeating elements, ready for the next pass.
 		 * Also check that these are not all EndOfMib
 		 */
 	    allDone = TRUE;		/* Check for some content */
 	    for ( var_ptr = asp->start;
 		  var_ptr != asp->end->next_variable;
 		  var_ptr = var_ptr->next_variable ) {
 				/* XXX: we don't know the size of the next
 					OID, so assume the maximum length */
 		if ( var_ptr->type != SNMP_ENDOFMIBVIEW )
 		{
 		var_ptr2 = snmp_add_null_var(asp->pdu, var_ptr->name, MAX_OID_LEN);
 		for ( i=var_ptr->name_length ; i<MAX_OID_LEN ; i++)
 		    var_ptr2->name[i] = 0;
 		var_ptr2->name_length = var_ptr->name_length;

 		    allDone = FALSE;
 		}
 	    }
 	    if ( allDone )
 		break;

 	    asp->start = asp->end->next_variable;
 	    while ( asp->end->next_variable != NULL )
 		asp->end = asp->end->next_variable;

 	    status = handle_next_pass( asp );
 	    if ( status != SNMP_ERR_NOERROR )
 		break;
 	    if ( asp->outstanding_requests != NULL )
 		return 1;
 	}
 	break;

     case SNMP_MSG_SET:
     	    /*
 	     * SETS require 3-4 passes through the var_op_list.  The first two
 	     * passes verify that all types, lengths, and values are valid
 	     * and may reserve resources and the third does the set and a
 	     * fourth executes any actions.  Then the identical GET RESPONSE
 	     * packet is returned.
 	     * If either of the first two passes returns an error, another
 	     * pass is made so that any reserved resources can be freed.
 	     * If the third pass returns an error, another pass is made so that
 	     * any changes can be reversed.
 	     * If the fourth pass (or any of the error handling passes)
 	     * return an error, we'd rather not know about it!
 	     */
 	if ( asp->mode == RESERVE1 ) {
             snmp_increment_statistic(STAT_SNMPINSETREQUESTS);
 	    asp->rw      = WRITE;

 	    status = handle_next_pass( asp );

 	    if ( status != SNMP_ERR_NOERROR )
 	        asp->mode = FREE;
 	    else
 	        asp->mode = RESERVE2;

 	    if ( asp->outstanding_requests != NULL )
 		return 1;
 	}

 	if ( asp->mode == RESERVE2 ) {
 	    status = handle_next_pass( asp );

 	    if ( status != SNMP_ERR_NOERROR )
 	        asp->mode = FREE;
 	    else
 	        asp->mode = ACTION;

 	    if ( asp->outstanding_requests != NULL )
 		return 1;
 	}

 	if ( asp->mode == ACTION ) {
 	    status = handle_next_pass( asp );

 	    if ( status != SNMP_ERR_NOERROR )
 	        asp->mode = UNDO;
 	    else
 	        asp->mode = COMMIT;

 	    if ( asp->outstanding_requests != NULL )
 		return 1;
 	}

 	if ( asp->mode == COMMIT ) {
 	    status = handle_next_pass( asp );

 	    if ( status != SNMP_ERR_NOERROR )
 	        asp->mode = FINISHED_FAILURE;	/* or UNDO ? */
 	    else
 	        asp->mode = FINISHED_SUCCESS;	/* or FREE ? */

 	    if ( asp->outstanding_requests != NULL )
 		return 1;
 	}

 	if ( asp->mode == UNDO ) {
 	    status = handle_next_pass( asp );

 	    asp->mode = FINISHED_FAILURE;
 	    break;
 	}

 	if ( asp->mode == FREE ) {
 	    (void) handle_next_pass( asp );
 	    break;
 	}

 	break;

     case SNMP_MSG_RESPONSE:
         snmp_increment_statistic(STAT_SNMPINGETRESPONSES);
 	free( asp );
 	return 0;
     case SNMP_MSG_TRAP:
     case SNMP_MSG_TRAP2:
         snmp_increment_statistic(STAT_SNMPINTRAPS);
 	free( asp );
 	return 0;
     default:
         snmp_increment_statistic(STAT_SNMPINASNPARSEERRS);
 	free( asp );
 	return 0;
     }


     if ( asp->outstanding_requests != NULL ) {
 	asp->status = status;
 	asp->next = agent_session_list;
 	agent_session_list = asp;
     }
     else {
 	if ( status == SNMP_ERR_NOERROR ) {
 	    snmp_increment_statistic_by(
 		(asp->pdu->command == SNMP_MSG_SET ?
 			STAT_SNMPINTOTALSETVARS : STAT_SNMPINTOTALREQVARS ),
 	    	count_varbinds( asp->pdu ));
 	}
 	asp->pdu->command = SNMP_MSG_RESPONSE;
 	asp->pdu->errstat = status;
 	snmp_send( asp->session, asp->pdu );
 	snmp_increment_statistic(STAT_SNMPOUTPKTS);
 	snmp_increment_statistic(STAT_SNMPOUTGETRESPONSES);
 	free( asp );
     }

     return 1;
 }


 int
 handle_next_pass(struct agent_snmp_session  *asp)
 {
     int status;
     struct snmp_pdu *pdu = asp->pdu;
     struct request_list *req_p, *next_req;


         if ( asp->outstanding_requests != NULL )
 	    return SNMP_ERR_NOERROR;
 	status = handle_var_list( asp );
         if ( asp->outstanding_requests != NULL ) {
 	    if ( status == SNMP_ERR_NOERROR ) {
 		/* Send out any subagent requests */
 		for ( req_p = asp->outstanding_requests ;
 			req_p != NULL ; req_p = req_p->next_request ) {

 		    snmp_async_send( req_p->session,  req_p->pdu,
 				      req_p->callback, req_p->cb_data );
 		    asp->pdu = snmp_clone_pdu( pdu );
 		    asp->pdu->variables = pdu->variables;
 		    pdu->variables = NULL;
 		}
 	    }
 	    else {
 	    	/* discard outstanding requests */
 		for ( req_p = asp->outstanding_requests ;
 			req_p != NULL ; req_p = next_req ) {

 			next_req = req_p->next_request;
 			free( req_p );
 		}
 		asp->outstanding_requests = NULL;
 	    }
 	}
 	return status;
 }


 int
 handle_var_list(struct agent_snmp_session  *asp)
 {
     struct variable_list *varbind_ptr;
     u_char  statType;
     u_char *statP;
     size_t  statLen;
     u_short acl;
     WriteMethod *write_method;
     AddVarMethod *add_method;
     int	    noSuchObject;
     int     count, view;

     count = 0;
     varbind_ptr = asp->start;
     if ( !varbind_ptr ) {
 	return SNMP_ERR_NOERROR;
     }

     while (1) {

 	count++;
 statp_loop:
 	statP = getStatPtr(  varbind_ptr->name,
 			   &varbind_ptr->name_length,
 			   &statType, &statLen, &acl,
 			   asp->exact, &write_method, asp->pdu, &noSuchObject);

 	if (statP == NULL && (asp->rw != WRITE || write_method == NULL)) {
 	    	varbind_ptr->val.integer   = NULL;
 	    	varbind_ptr->val_len = 0;
 		if ( asp->exact ) {
 	            if ( noSuchObject == TRUE ){
 		        statType = SNMP_NOSUCHOBJECT;
 		    } else {
 		        statType = SNMP_NOSUCHINSTANCE;
 		    }
 		} else {
 	            statType = SNMP_ENDOFMIBVIEW;
 		}
 		if (asp->pdu->version == SNMP_VERSION_1) {
 		    asp->pdu->errstat = SNMP_ERR_NOSUCHNAME;
 		    asp->pdu->errindex = count;
 		    return SNMP_ERR_NOSUCHNAME;
 		}
 		else
 		    varbind_ptr->type = statType;
 	}
                 /* Delegated variables should be added to the
                    relevant outgoing request */
         else if ( IS_DELEGATED(statType)) {
                 add_method = (AddVarMethod*)statP;
                 statType = (*add_method)( asp, varbind_ptr );
         }
 		/* GETNEXT/GETBULK should just skip inaccessible entries */
 	else if ((view = in_a_view(varbind_ptr->name, &varbind_ptr->name_length,
 				   asp->pdu, varbind_ptr->type))
 			 && !asp->exact) {
 		if (view != 5) send_easy_trap(SNMP_TRAP_AUTHFAIL, 0);
 		goto statp_loop;
 	}
 		/* Other access problems are permanent */
 	else if (( asp->rw == WRITE && !(acl & 2)) || view) {
 	    if (asp->pdu->version == SNMP_VERSION_1 || asp->rw != WRITE) {
 		if (ds_get_boolean(DS_APPLICATION_ID, DS_AGENT_VERBOSE))
                   DEBUGMSGTL(("snmp_agent", "    >> noSuchName (read-only)\n"));
 		ERROR_MSG("read-only");
 		statType = SNMP_ERR_NOSUCHNAME;
 	    }
 	    else {
 		if (ds_get_boolean(DS_APPLICATION_ID, DS_AGENT_VERBOSE))
                   DEBUGMSGTL(("snmp_agent", "    >> notWritable\n"));
 		ERROR_MSG("Not Writable");
 		statType = SNMP_ERR_NOTWRITABLE;
 	    }
 	    asp->pdu->errstat = statType;
 	    asp->pdu->errindex = count;
 	    return statType;
         }
 	else {
             /* dump verbose info */
 	    if (ds_get_boolean(DS_APPLICATION_ID, DS_AGENT_VERBOSE) && statP)
 	        dump_var(varbind_ptr->name, varbind_ptr->name_length,
 				statType, statP, statLen);

 		/*  FINALLY we can act on SET requests ....*/
 	    if ( asp->rw == WRITE ) {
 	        if ( write_method != NULL ) {
 		    statType = (*write_method)(asp->mode,
                                                varbind_ptr->val.string,
                                                varbind_ptr->type,
                                                varbind_ptr->val_len, statP,
                                                varbind_ptr->name,
                                                varbind_ptr->name_length);
                     if (statType != SNMP_ERR_NOERROR) {
                       asp->pdu->errstat = statType;
                       asp->pdu->errindex = count;
                       return statType;
                     }
 		}
 		else {
                     if (!goodValue(varbind_ptr->type, varbind_ptr->val_len,
                                     statType, statLen)){
                         if (asp->pdu->version == SNMP_VERSION_1)
                             statType = SNMP_ERR_BADVALUE;
                         else
                             statType = SNMP_ERR_WRONGTYPE; /* poor approximation */
 			asp->pdu->errstat = statType;
 			asp->pdu->errindex = count;
 			return statType;
                     }
                     /* actually do the set if necessary */
                     if (asp->mode == COMMIT)
                         setVariable(varbind_ptr->val.string, varbind_ptr->type,
                                     varbind_ptr->val_len, statP, statLen);
                 }
 	    }
 		/* ... or save the results from assorted GETs */
 	    else {
 		     snmp_set_var_value(varbind_ptr, statP, statLen);
 		     varbind_ptr->type = statType;
 	    }
 	}

 	if ( varbind_ptr == asp->end )
 	     return SNMP_ERR_NOERROR;
 	varbind_ptr = varbind_ptr->next_variable;
 	if ( asp->mode == RESERVE1 )
 	    snmp_vars_inc++;
     }
 }


 static int
 goodValue(u_char inType,
 	  size_t inLen,
 	  u_char actualType,
 	  size_t actualLen)
 {
     if (inLen > actualLen)
 	return FALSE;
     return (inType == actualType);
 }

 static void
 setVariable(u_char *var_val,
 	    u_char var_val_type,
 	    size_t var_val_len,
 	    u_char *statP,
 	    size_t statLen)
 {
     size_t buffersize = 1000;

     switch(var_val_type){
 	case ASN_INTEGER:
 	    asn_parse_int(var_val, &buffersize, &var_val_type, (long *)statP, statLen);
 	    break;
 	case ASN_COUNTER:
 	case ASN_GAUGE:
 	case ASN_TIMETICKS:
 	    asn_parse_unsigned_int(var_val, &buffersize, &var_val_type, (u_long *)statP, statLen);
 	    break;
 	case ASN_COUNTER64:
 	    asn_parse_unsigned_int64(var_val, &buffersize, &var_val_type,
 				     (struct counter64 *)statP, statLen);
 	    break;
 	case ASN_OCTET_STR:
 	case ASN_IPADDRESS:
 	case ASN_OPAQUE:
 	case ASN_NSAP:
 	    asn_parse_string(var_val, &buffersize, &var_val_type, statP, &statLen);
 	    break;
 	case ASN_OBJECT_ID:
 	    asn_parse_objid(var_val, &buffersize, &var_val_type, (oid *)statP, &statLen);
 	    break;
 	case ASN_BIT_STR:
 	    asn_parse_bitstring(var_val, &buffersize, &var_val_type, statP, &statLen);
 	    break;
     }
 }
	/*
	* snmp_agent.c
	*
	* Simple Network Management Protocol (RFC 1067).
	*/
	/***********************************************************
	Copyright 1988, 1989 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 <config.h>

	#include <sys/types.h>
	#ifdef HAVE_STDLIB_H
	#include <stdlib.h>
	#endif
	#if HAVE_UNISTD_H
	#include <unistd.h>
	#endif
	#if HAVE_STRING_H
	#include <string.h>
	#endif
	#if TIME_WITH_SYS_TIME
	# ifdef WIN32
	# include <sys/timeb.h>
	# else
	# include <sys/time.h>
	# endif
	# include <time.h>
	#else
	# if HAVE_SYS_TIME_H
	# include <sys/time.h>
	# else
	# include <time.h>
	# endif
	#endif
	#if HAVE_SYS_SELECT_H
	#include <sys/select.h>
	#endif
	#if HAVE_NETINET_IN_H
	#include <netinet/in.h>
	#endif
	#include <errno.h>
	#if HAVE_WINSOCK_H
	#include <winsock.h>
	#endif

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

	#include "asn1.h"
	#define SNMP_NEED_REQUEST_LIST
	#include "snmp_api.h"
	#include "snmp_impl.h"
	#include "snmp.h"
	#include "mib.h"
	#include "snmp_client.h"

	#include "snmp_vars.h"
	#include "snmpd.h"
	#include "mibgroup/struct.h"
	#include "mibgroup/util_funcs.h"
	#include "var_struct.h"
	#include "read_config.h"
	#include "snmp_logging.h"
	#include "snmp_debug.h"
	#include "mib_module_config.h"

	#include "default_store.h"
	#include "ds_agent.h"
	#include "snmp_agent.h"
	#include "agent_trap.h"

	static int snmp_vars_inc;

	static struct agent_snmp_session *agent_session_list = NULL;


	static void dump_var(oid , size_t, int, void , size_t);
	static int goodValue(u_char, size_t, u_char, size_t);
	static void setVariable(u_char , u_char, size_t, u_char , size_t);

	static void dump_var (
	oid *var_name,
	size_t var_name_len,
	int statType,
	void *statP,
	size_t statLen)
	{
	char buf [SPRINT_MAX_LEN];
	struct variable_list temp_var;

	temp_var.type = statType;
	temp_var.val.string = (u_char *)statP;
	temp_var.val_len = statLen;
	sprint_variable (buf, var_name, var_name_len, &temp_var);
	snmp_log(LOG_INFO, " >> %s\n", buf);
	}


	int getNextSessID()
	{
	static int SessionID = 0;

	return ++SessionID;
	}

	int
	agent_check_and_process(int block) {
	int numfds;
	fd_set fdset;
	struct timeval timeout, *tvp = &timeout;
	int count;
	int fakeblock=0;

	tvp = &timeout;

	numfds = 0;
	FD_ZERO(&fdset);
	snmp_select_info(&numfds, &fdset, tvp, &fakeblock);
	if (block == 1 && fakeblock == 1)
	tvp = NULL; /* block without timeout */
	else if (block == 0) {
	tvp->tv_sec = 0;
	tvp->tv_usec = 0;
	}

	count = select(numfds, &fdset, 0, 0, tvp);

	if (count > 0){
	/* packets found, process them */
	snmp_read(&fdset);
	} else switch(count){
	case 0:
	snmp_timeout();
	break;
	case -1:
	if (errno == EINTR){
	return -1;
	} else {
	snmp_log_perror("select");
	}
	return -1;
	default:
	snmp_log(LOG_ERR, "select returned %d\n", count);
	return -1;
	} /* endif -- count>0 */
	return count;
	}


	/*
	* The session is created using the "traditional API" routine snmp_open()
	* so is linked into the global library Sessions list. It also opens a
	* socket that listens for incoming requests.
	*
	* The agent runs in an infinite loop (in the 'receive()' routine),
	* which calls snmp_read() when such a request is received on this socket.
	* This routine then traverses the library 'Sessions' list to identify the
	* relevant session and eventually invokes '_sess_read'.
	* This then processes the incoming packet, calling the pre_parse, parse,
	* post_parse and callback routines in turn.
	*/

	/* Global access to the primary session structure for this agent.
	for Index Allocation use initially. */
	struct snmp_session *main_session;

	void
	init_master_agent(int dest_port,
	int (pre_parse) (struct snmp_session , snmp_ipaddr),
	int (post_parse) (struct snmp_session , struct snmp_pdu *,int))
	{
	struct snmp_session sess, *session;

	if ( ds_get_boolean(DS_APPLICATION_ID, DS_AGENT_ROLE) != MASTER_AGENT )
	return;

	DEBUGMSGTL(("snmpd","installing master agent on port %d", dest_port));

	snmp_sess_init( &sess );

	sess.version = SNMP_DEFAULT_VERSION;
	sess.peername = SNMP_DEFAULT_PEERNAME;
	sess.community_len = SNMP_DEFAULT_COMMUNITY_LEN;

	sess.local_port = dest_port;
	sess.callback = handle_snmp_packet;
	sess.authenticator = NULL;
	sess.flags = ds_get_int(DS_APPLICATION_ID, DS_AGENT_FLAGS);
	session = snmp_open_ex( &sess, pre_parse, 0, post_parse, 0, 0 );

	if ( session == NULL ) {
	/* diagnose snmp_open errors with the input struct snmp_session pointer */
	snmp_sess_perror("init_master_agent", &sess);
	exit(1);
	}
	main_session = session;
	}

	struct agent_snmp_session *
	init_agent_snmp_session( struct snmp_session session, struct snmp_pdu pdu )
	{
	struct agent_snmp_session *asp;

	asp = malloc( sizeof( struct agent_snmp_session ));
	if ( asp == NULL )
	return NULL;
	asp->start = pdu->variables;
	asp->end = pdu->variables;
	if ( asp->end != NULL )
	while ( asp->end->next_variable != NULL )
	asp->end = asp->end->next_variable;
	asp->session = session;
	asp->pdu = pdu;
	asp->rw = READ;
	asp->exact = TRUE;
	asp->outstanding_requests = NULL;
	asp->next = NULL;
	asp->mode = RESERVE1;
	asp->status = SNMP_ERR_NOERROR;

	return asp;
	}

	int
	count_varbinds( struct snmp_pdu *pdu )
	{
	int count = 0;
	struct variable_list *var_ptr;

	for ( var_ptr = pdu->variables ; var_ptr != NULL ;
	var_ptr = var_ptr->next_variable )
	count++;

	return count;
	}

	int
	handle_snmp_packet(int operation, struct snmp_session *session, int reqid,
	struct snmp_pdu pdu, void magic)
	{
	struct agent_snmp_session *asp;
	int status, allDone, i;
	struct variable_list var_ptr, var_ptr2;

	if ( magic == NULL ) {
	asp = init_agent_snmp_session( session, snmp_clone_pdu(pdu) );
	status = SNMP_ERR_NOERROR;
	}
	else {
	asp = (struct agent_snmp_session *)magic;
	status = asp->status;
	}

	if (asp->outstanding_requests != NULL)
	return 1;

	switch (pdu->command) {
	case SNMP_MSG_GET:
	if ( asp->mode != RESERVE1 )
	break; /* Single pass */
	snmp_increment_statistic(STAT_SNMPINGETREQUESTS);
	status = handle_next_pass( asp );
	asp->mode = RESERVE2;
	break;

	case SNMP_MSG_GETNEXT:
	if ( asp->mode != RESERVE1 )
	break; /* Single pass */
	snmp_increment_statistic(STAT_SNMPINGETNEXTS);
	asp->exact = FALSE;
	status = handle_next_pass( asp );
	asp->mode = RESERVE2;
	break;

	case SNMP_MSG_GETBULK:
	/*
	* GETBULKS require multiple passes. The first pass handles the
	* explicitly requested varbinds, and subsequent passes append
	* to the existing var_op_list. Each pass (after the first)
	* uses the results of the preceeding pass as the input list
	* (delimited by the start & end pointers.
	* Processing is terminated if all entries in a pass are
	* EndOfMib, or the maximum number of repetitions are made.
	*/
	if ( asp->mode == RESERVE1 ) {
	snmp_increment_statistic(STAT_SNMPINGETREQUESTS);
	asp->exact = FALSE;
	/*
	* Limit max repetitions to something reasonable
	* XXX: We should figure out what will fit somehow...
	*/
	if ( asp->pdu->errindex > 100 )
	asp->pdu->errindex = 100;

	status = handle_next_pass( asp ); /* First pass */
	asp->mode = RESERVE2;
	if ( status != SNMP_ERR_NOERROR )
	break;

	while ( asp->pdu->errstat-- > 0 ) /* Skip non-repeaters */
	asp->start = asp->start->next_variable;
	asp->pdu->errindex--; /* Handled first repetition */

	if ( asp->outstanding_requests != NULL )
	return 1;
	}

	while ( asp->pdu->errindex-- > 0 ) { /* Process repeaters */
	/*
	* Add new variable structures for the
	* repeating elements, ready for the next pass.
	* Also check that these are not all EndOfMib
	*/
	allDone = TRUE; /* Check for some content */
	for ( var_ptr = asp->start;
	var_ptr != asp->end->next_variable;
	var_ptr = var_ptr->next_variable ) {
	/* XXX: we don't know the size of the next
	OID, so assume the maximum length */
	if ( var_ptr->type != SNMP_ENDOFMIBVIEW )
	{
	var_ptr2 = snmp_add_null_var(asp->pdu, var_ptr->name, MAX_OID_LEN);
	for ( i=var_ptr->name_length ; i<MAX_OID_LEN ; i++)
	var_ptr2->name[i] = 0;
	var_ptr2->name_length = var_ptr->name_length;

	allDone = FALSE;
	}
	}
	if ( allDone )
	break;

	asp->start = asp->end->next_variable;
	while ( asp->end->next_variable != NULL )
	asp->end = asp->end->next_variable;

	status = handle_next_pass( asp );
	if ( status != SNMP_ERR_NOERROR )
	break;
	if ( asp->outstanding_requests != NULL )
	return 1;
	}
	break;

	case SNMP_MSG_SET:
	/*
	* SETS require 3-4 passes through the var_op_list. The first two
	* passes verify that all types, lengths, and values are valid
	* and may reserve resources and the third does the set and a
	* fourth executes any actions. Then the identical GET RESPONSE
	* packet is returned.
	* If either of the first two passes returns an error, another
	* pass is made so that any reserved resources can be freed.
	* If the third pass returns an error, another pass is made so that
	* any changes can be reversed.
	* If the fourth pass (or any of the error handling passes)
	* return an error, we'd rather not know about it!
	*/
	if ( asp->mode == RESERVE1 ) {
	snmp_increment_statistic(STAT_SNMPINSETREQUESTS);
	asp->rw = WRITE;

	status = handle_next_pass( asp );

	if ( status != SNMP_ERR_NOERROR )
	asp->mode = FREE;
	else
	asp->mode = RESERVE2;

	if ( asp->outstanding_requests != NULL )
	return 1;
	}

	if ( asp->mode == RESERVE2 ) {
	status = handle_next_pass( asp );

	if ( status != SNMP_ERR_NOERROR )
	asp->mode = FREE;
	else
	asp->mode = ACTION;

	if ( asp->outstanding_requests != NULL )
	return 1;
	}

	if ( asp->mode == ACTION ) {
	status = handle_next_pass( asp );

	if ( status != SNMP_ERR_NOERROR )
	asp->mode = UNDO;
	else
	asp->mode = COMMIT;

	if ( asp->outstanding_requests != NULL )
	return 1;
	}

	if ( asp->mode == COMMIT ) {
	status = handle_next_pass( asp );

	if ( status != SNMP_ERR_NOERROR )
	asp->mode = FINISHED_FAILURE; /* or UNDO ? */
	else
	asp->mode = FINISHED_SUCCESS; /* or FREE ? */

	if ( asp->outstanding_requests != NULL )
	return 1;
	}

	if ( asp->mode == UNDO ) {
	status = handle_next_pass( asp );

	asp->mode = FINISHED_FAILURE;
	break;
	}

	if ( asp->mode == FREE ) {
	(void) handle_next_pass( asp );
	break;
	}

	break;

	case SNMP_MSG_RESPONSE:
	snmp_increment_statistic(STAT_SNMPINGETRESPONSES);
	free( asp );
	return 0;
	case SNMP_MSG_TRAP:
	case SNMP_MSG_TRAP2:
	snmp_increment_statistic(STAT_SNMPINTRAPS);
	free( asp );
	return 0;
	default:
	snmp_increment_statistic(STAT_SNMPINASNPARSEERRS);
	free( asp );
	return 0;
	}



	if ( asp->outstanding_requests != NULL ) {
	asp->status = status;
	asp->next = agent_session_list;
	agent_session_list = asp;
	}
	else {
	if ( status == SNMP_ERR_NOERROR ) {
	snmp_increment_statistic_by(
	(asp->pdu->command == SNMP_MSG_SET ?
	STAT_SNMPINTOTALSETVARS : STAT_SNMPINTOTALREQVARS ),
	count_varbinds( asp->pdu ));
	}
	asp->pdu->command = SNMP_MSG_RESPONSE;
	asp->pdu->errstat = status;
	snmp_send( asp->session, asp->pdu );
	snmp_increment_statistic(STAT_SNMPOUTPKTS);
	snmp_increment_statistic(STAT_SNMPOUTGETRESPONSES);
	free( asp );
	}

	return 1;
	}


	int
	handle_next_pass(struct agent_snmp_session *asp)
	{
	int status;
	struct snmp_pdu *pdu = asp->pdu;
	struct request_list req_p, next_req;


	if ( asp->outstanding_requests != NULL )
	return SNMP_ERR_NOERROR;
	status = handle_var_list( asp );
	if ( asp->outstanding_requests != NULL ) {
	if ( status == SNMP_ERR_NOERROR ) {
	/* Send out any subagent requests */
	for ( req_p = asp->outstanding_requests ;
	req_p != NULL ; req_p = req_p->next_request ) {

	snmp_async_send( req_p->session, req_p->pdu,
	req_p->callback, req_p->cb_data );
	asp->pdu = snmp_clone_pdu( pdu );
	asp->pdu->variables = pdu->variables;
	pdu->variables = NULL;
	}
	}
	else {
	/* discard outstanding requests */
	for ( req_p = asp->outstanding_requests ;
	req_p != NULL ; req_p = next_req ) {

	next_req = req_p->next_request;
	free( req_p );
	}
	asp->outstanding_requests = NULL;
	}
	}
	return status;
	}


	int
	handle_var_list(struct agent_snmp_session *asp)
	{
	struct variable_list *varbind_ptr;
	u_char statType;
	u_char *statP;
	size_t statLen;
	u_short acl;
	WriteMethod *write_method;
	AddVarMethod *add_method;
	int noSuchObject;
	int count, view;

	count = 0;
	varbind_ptr = asp->start;
	if ( !varbind_ptr ) {
	return SNMP_ERR_NOERROR;
	}

	while (1) {

	count++;
	statp_loop:
	statP = getStatPtr( varbind_ptr->name,
	&varbind_ptr->name_length,
	&statType, &statLen, &acl,
	asp->exact, &write_method, asp->pdu, &noSuchObject);

	if (statP == NULL && (asp->rw != WRITE \|\| write_method == NULL)) {
	varbind_ptr->val.integer = NULL;
	varbind_ptr->val_len = 0;
	if ( asp->exact ) {
	if ( noSuchObject == TRUE ){
	statType = SNMP_NOSUCHOBJECT;
	} else {
	statType = SNMP_NOSUCHINSTANCE;
	}
	} else {
	statType = SNMP_ENDOFMIBVIEW;
	}
	if (asp->pdu->version == SNMP_VERSION_1) {
	asp->pdu->errstat = SNMP_ERR_NOSUCHNAME;
	asp->pdu->errindex = count;
	return SNMP_ERR_NOSUCHNAME;
	}
	else
	varbind_ptr->type = statType;
	}
	/* Delegated variables should be added to the
	relevant outgoing request */
	else if ( IS_DELEGATED(statType)) {
	add_method = (AddVarMethod*)statP;
	statType = (*add_method)( asp, varbind_ptr );
	}
	/* GETNEXT/GETBULK should just skip inaccessible entries */
	else if ((view = in_a_view(varbind_ptr->name, &varbind_ptr->name_length,
	asp->pdu, varbind_ptr->type))
	&& !asp->exact) {
	if (view != 5) send_easy_trap(SNMP_TRAP_AUTHFAIL, 0);
	goto statp_loop;
	}
	/* Other access problems are permanent */
	else if (( asp->rw == WRITE && !(acl & 2)) \|\| view) {
	if (asp->pdu->version == SNMP_VERSION_1 \|\| asp->rw != WRITE) {
	if (ds_get_boolean(DS_APPLICATION_ID, DS_AGENT_VERBOSE))
	DEBUGMSGTL(("snmp_agent", " >> noSuchName (read-only)\n"));
	ERROR_MSG("read-only");
	statType = SNMP_ERR_NOSUCHNAME;
	}
	else {
	if (ds_get_boolean(DS_APPLICATION_ID, DS_AGENT_VERBOSE))
	DEBUGMSGTL(("snmp_agent", " >> notWritable\n"));
	ERROR_MSG("Not Writable");
	statType = SNMP_ERR_NOTWRITABLE;
	}
	asp->pdu->errstat = statType;
	asp->pdu->errindex = count;
	return statType;
	}
	else {
	/* dump verbose info */
	if (ds_get_boolean(DS_APPLICATION_ID, DS_AGENT_VERBOSE) && statP)
	dump_var(varbind_ptr->name, varbind_ptr->name_length,
	statType, statP, statLen);

	/* FINALLY we can act on SET requests ....*/
	if ( asp->rw == WRITE ) {
	if ( write_method != NULL ) {
	statType = (*write_method)(asp->mode,
	varbind_ptr->val.string,
	varbind_ptr->type,
	varbind_ptr->val_len, statP,
	varbind_ptr->name,
	varbind_ptr->name_length);
	if (statType != SNMP_ERR_NOERROR) {
	asp->pdu->errstat = statType;
	asp->pdu->errindex = count;
	return statType;
	}
	}
	else {
	if (!goodValue(varbind_ptr->type, varbind_ptr->val_len,
	statType, statLen)){
	if (asp->pdu->version == SNMP_VERSION_1)
	statType = SNMP_ERR_BADVALUE;
	else
	statType = SNMP_ERR_WRONGTYPE; /* poor approximation */
	asp->pdu->errstat = statType;
	asp->pdu->errindex = count;
	return statType;
	}
	/* actually do the set if necessary */
	if (asp->mode == COMMIT)
	setVariable(varbind_ptr->val.string, varbind_ptr->type,
	varbind_ptr->val_len, statP, statLen);
	}
	}
	/* ... or save the results from assorted GETs */
	else {
	snmp_set_var_value(varbind_ptr, statP, statLen);
	varbind_ptr->type = statType;
	}
	}

	if ( varbind_ptr == asp->end )
	return SNMP_ERR_NOERROR;
	varbind_ptr = varbind_ptr->next_variable;
	if ( asp->mode == RESERVE1 )
	snmp_vars_inc++;
	}
	}



	static int
	goodValue(u_char inType,
	size_t inLen,
	u_char actualType,
	size_t actualLen)
	{
	if (inLen > actualLen)
	return FALSE;
	return (inType == actualType);
	}

	static void
	setVariable(u_char *var_val,
	u_char var_val_type,
	size_t var_val_len,
	u_char *statP,
	size_t statLen)
	{
	size_t buffersize = 1000;

	switch(var_val_type){
	case ASN_INTEGER:
	asn_parse_int(var_val, &buffersize, &var_val_type, (long *)statP, statLen);
	break;
	case ASN_COUNTER:
	case ASN_GAUGE:
	case ASN_TIMETICKS:
	asn_parse_unsigned_int(var_val, &buffersize, &var_val_type, (u_long *)statP, statLen);
	break;
	case ASN_COUNTER64:
	asn_parse_unsigned_int64(var_val, &buffersize, &var_val_type,
	(struct counter64 *)statP, statLen);
	break;
	case ASN_OCTET_STR:
	case ASN_IPADDRESS:
	case ASN_OPAQUE:
	case ASN_NSAP:
	asn_parse_string(var_val, &buffersize, &var_val_type, statP, &statLen);
	break;
	case ASN_OBJECT_ID:
	asn_parse_objid(var_val, &buffersize, &var_val_type, (oid *)statP, &statLen);
	break;
	case ASN_BIT_STR:
	asn_parse_bitstring(var_val, &buffersize, &var_val_type, statP, &statLen);
	break;
	}
	}