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;
if ( check_access(pdu) != 0) {
/* access control setup is incorrect */
send_easy_trap(SNMP_TRAP_AUTHFAIL, 0);
if (asp->pdu->version != SNMP_VERSION_1 && asp->pdu->version != SNMP_VERSION_2c) {
asp->pdu->errstat = SNMP_ERR_AUTHORIZATIONERROR;
asp->pdu->command = SNMP_MSG_RESPONSE;
snmp_increment_statistic(STAT_SNMPOUTPKTS);
snmp_send( asp->session, asp->pdu );
free( asp );
return 1;
} else {
/* drop the request */
free( asp );
return 0;
}
}
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 ) {
status = SNMP_ERR_COMMITFAILED;
asp->mode = FINISHED_FAILURE;
}
else
asp->mode = FINISHED_SUCCESS;
if ( asp->outstanding_requests != NULL )
return 1;
}
if ( asp->mode == UNDO ) {
if (handle_next_pass( asp ) != SNMP_ERR_NOERROR )
status = SNMP_ERR_UNDOFAILED;
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 {
/*
* May need to "dumb down" a SET error status for a
* v1 query. See RFC2576 - section 4.3
*/
if (( asp->pdu->command == SNMP_MSG_SET ) &&
( asp->pdu->version == SNMP_VERSION_1 )) {
switch ( status ) {
case SNMP_ERR_WRONGVALUE:
case SNMP_ERR_WRONGENCODING:
case SNMP_ERR_WRONGTYPE:
case SNMP_ERR_WRONGLENGTH:
case SNMP_ERR_INCONSISTENTVALUE:
status = SNMP_ERR_BADVALUE;
break;
case SNMP_ERR_NOACCESS:
case SNMP_ERR_NOTWRITABLE:
case SNMP_ERR_NOCREATION:
case SNMP_ERR_INCONSISTENTNAME:
case SNMP_ERR_AUTHORIZATIONERROR:
status = SNMP_ERR_NOSUCHNAME;
break;
case SNMP_ERR_RESOURCEUNAVAILABLE:
case SNMP_ERR_COMMITFAILED:
case SNMP_ERR_UNDOFAILED:
status = SNMP_ERR_GENERR;
break;
}
}
/*
* Similarly we may need to "dumb down" v2 exception
* types to throw an error for a v1 query.
* See RFC2576 - section 4.1.2.3
*/
if (( asp->pdu->command != SNMP_MSG_SET ) &&
( asp->pdu->version == SNMP_VERSION_1 )) {
for ( var_ptr = asp->pdu->variables, i=0 ;
var_ptr != NULL ;
var_ptr = var_ptr->next_variable, i++ ) {
switch ( var_ptr->type ) {
case SNMP_NOSUCHOBJECT:
case SNMP_NOSUCHINSTANCE:
case SNMP_ENDOFMIBVIEW:
case ASN_COUNTER64:
status = SNMP_ERR_NOSUCHNAME;
asp->pdu->errindex=i;
break;
}
}
}
if ( status == SNMP_ERR_NOERROR ) {
snmp_increment_statistic_by(
(asp->pdu->command == SNMP_MSG_SET ?
STAT_SNMPINTOTALSETVARS : STAT_SNMPINTOTALREQVARS ),
count_varbinds( asp->pdu ));
}
else {
/*
* Use a copy of the original request
* to report failures.
*/
i = asp->pdu->errindex;
snmp_free_pdu( asp->pdu );
asp->pdu = snmp_clone_pdu( pdu );
asp->pdu->errindex = i;
}
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_master_agentx_packet(int operation,
netsnmp_session * session,
int reqid, netsnmp_pdu *pdu, void *magic)
{
netsnmp_agent_session *asp;
if (operation == NETSNMP_CALLBACK_OP_DISCONNECT) {
DEBUGMSGTL(("agentx/master",
"transport disconnect on session %8p\n", session));
/*
* Shut this session down gracefully.
*/
close_agentx_session(session, -1);
return 1;
} else if (operation == NETSNMP_CALLBACK_OP_CONNECT) {
DEBUGMSGTL(("agentx/master",
"transport connect on session %8p\n", session));
return 1;
} else if (operation != NETSNMP_CALLBACK_OP_RECEIVED_MESSAGE) {
DEBUGMSGTL(("agentx/master", "unexpected callback op %d\n",
operation));
return 1;
}
/*
* Okay, it's a NETSNMP_CALLBACK_OP_RECEIVED_MESSAGE op.
*/
if (magic) {
asp = (netsnmp_agent_session *) magic;
} else {
asp = init_agent_snmp_session(session, pdu);
}
DEBUGMSGTL(("agentx/master", "handle pdu (req=0x%lx,trans=0x%lx,sess=0x%lx)\n",
(unsigned long)pdu->reqid, (unsigned long)pdu->transid,
(unsigned long)pdu->sessid));
switch (pdu->command) {
case AGENTX_MSG_OPEN:
asp->pdu->sessid = open_agentx_session(session, pdu);
if (asp->pdu->sessid == -1)
asp->status = session->s_snmp_errno;
break;
case AGENTX_MSG_CLOSE:
asp->status = close_agentx_session(session, pdu->sessid);
break;
case AGENTX_MSG_REGISTER:
asp->status = register_agentx_list(session, pdu);
break;
case AGENTX_MSG_UNREGISTER:
asp->status = unregister_agentx_list(session, pdu);
break;
case AGENTX_MSG_INDEX_ALLOCATE:
asp->status = allocate_idx_list(session, asp->pdu);
if (asp->status != AGENTX_ERR_NOERROR) {
snmp_free_pdu(asp->pdu);
asp->pdu = snmp_clone_pdu(pdu);
}
break;
case AGENTX_MSG_INDEX_DEALLOCATE:
asp->status = release_idx_list(session, pdu);
break;
case AGENTX_MSG_ADD_AGENT_CAPS:
asp->status = add_agent_caps_list(session, pdu);
break;
case AGENTX_MSG_REMOVE_AGENT_CAPS:
asp->status = remove_agent_caps_list(session, pdu);
break;
case AGENTX_MSG_NOTIFY:
asp->status = agentx_notify(session, pdu);
break;
case AGENTX_MSG_PING:
asp->status = agentx_ping_response(session, pdu);
break;
/*
* TODO: Other admin packets
*/
case AGENTX_MSG_GET:
case AGENTX_MSG_GETNEXT:
case AGENTX_MSG_GETBULK:
case AGENTX_MSG_TESTSET:
case AGENTX_MSG_COMMITSET:
case AGENTX_MSG_UNDOSET:
case AGENTX_MSG_CLEANUPSET:
case AGENTX_MSG_RESPONSE:
/*
* Shouldn't be handled here
*/
break;
default:
asp->status = AGENTX_ERR_PARSE_FAILED;
break;
}
asp->pdu->time = netsnmp_get_agent_uptime();
asp->pdu->command = AGENTX_MSG_RESPONSE;
asp->pdu->errstat = asp->status;
DEBUGMSGTL(("agentx/master", "send response, stat %d (req=0x%lx,trans="
"0x%lx,sess=0x%lx)\n",
asp->status, (unsigned long)pdu->reqid,
(unsigned long)pdu->transid, (unsigned long)pdu->sessid));
if (!snmp_send(asp->session, asp->pdu)) {
char *eb = NULL;
int pe, pse;
snmp_error(asp->session, &pe, &pse, &eb);
snmp_free_pdu(asp->pdu);
DEBUGMSGTL(("agentx/master", "FAILED %d %d %s\n", pe, pse, eb));
free(eb);
}
asp->pdu = NULL;
free_agent_snmp_session(asp);
return 1;
}
