/** |
* @file |
* SNMP input message processing (RFC1157). |
*/ |
/* |
* Copyright (c) 2006 Axon Digital Design B.V., The Netherlands. |
* All rights reserved. |
* |
* Redistribution and use in source and binary forms, with or without modification, |
* are permitted provided that the following conditions are met: |
* |
* 1. Redistributions of source code must retain the above copyright notice, |
* this list of conditions and the following disclaimer. |
* 2. Redistributions in binary form must reproduce the above copyright notice, |
* this list of conditions and the following disclaimer in the documentation |
* and/or other materials provided with the distribution. |
* 3. The name of the author may not be used to endorse or promote products |
* derived from this software without specific prior written permission. |
* |
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED |
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF |
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT |
* SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, |
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT |
* OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS |
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN |
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING |
* IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY |
* OF SUCH DAMAGE. |
* |
* Author: Christiaan Simons <christiaan.simons@axon.tv> |
*/ |
#include "lwip/opt.h" |
#if LWIP_SNMP /* don't build if not configured for use in lwipopts.h */ |
#include "lwip/ip_addr.h" |
#include "lwip/mem.h" |
#include "lwip/udp.h" |
#include "lwip/stats.h" |
#include "lwip/snmp.h" |
#include "lwip/snmp_asn1.h" |
#include "lwip/snmp_msg.h" |
#include "lwip/snmp_structs.h" |
#include <string.h> |
/* public (non-static) constants */ |
/** SNMP v1 == 0 */ |
const s32_t snmp_version = 0; |
/** default SNMP community string */ |
const char snmp_publiccommunity[7] = "public1" ; |
/* statically allocated buffers for SNMP_CONCURRENT_REQUESTS */ |
struct snmp_msg_pstat msg_input_list[SNMP_CONCURRENT_REQUESTS]; |
/* UDP Protocol Control Block */ |
struct udp_pcb *snmp1_pcb; |
static void snmp_recv( void *arg, struct udp_pcb *pcb, struct pbuf *p, struct ip_addr *addr, u16_t port); |
static err_t snmp_pdu_header_check( struct pbuf *p, u16_t ofs, u16_t pdu_len, u16_t *ofs_ret, struct snmp_msg_pstat *m_stat); |
static err_t snmp_pdu_dec_varbindlist( struct pbuf *p, u16_t ofs, u16_t *ofs_ret, struct snmp_msg_pstat *m_stat); |
/** |
* Starts SNMP Agent. |
* Allocates UDP pcb and binds it to IP_ADDR_ANY port 161. |
*/ |
void |
snmp_init( void ) |
{ |
struct snmp_msg_pstat *msg_ps; |
u8_t i; |
snmp1_pcb = udp_new(); |
if (snmp1_pcb != NULL) |
{ |
udp_recv(snmp1_pcb, snmp_recv, ( void *)SNMP_IN_PORT); |
udp_bind(snmp1_pcb, IP_ADDR_ANY, SNMP_IN_PORT); |
} |
msg_ps = &msg_input_list[0]; |
for (i=0; i<SNMP_CONCURRENT_REQUESTS; i++) |
{ |
msg_ps->state = SNMP_MSG_EMPTY; |
msg_ps->error_index = 0; |
msg_ps->error_status = SNMP_ES_NOERROR; |
msg_ps++; |
} |
trap_msg.pcb = snmp1_pcb; |
/* The coldstart trap will only be output |
if our outgoing interface is up & configured */ |
snmp_coldstart_trap(); |
} |
static void |
snmp_error_response( struct snmp_msg_pstat *msg_ps, u8_t error) |
{ |
snmp_varbind_list_free(&msg_ps->outvb); |
msg_ps->outvb = msg_ps->invb; |
msg_ps->invb.head = NULL; |
msg_ps->invb.tail = NULL; |
msg_ps->invb.count = 0; |
msg_ps->error_status = error; |
msg_ps->error_index = 1 + msg_ps->vb_idx; |
snmp_send_response(msg_ps); |
snmp_varbind_list_free(&msg_ps->outvb); |
msg_ps->state = SNMP_MSG_EMPTY; |
} |
static void |
snmp_ok_response( struct snmp_msg_pstat *msg_ps) |
{ |
err_t err_ret; |
err_ret = snmp_send_response(msg_ps); |
if (err_ret == ERR_MEM) |
{ |
/* serious memory problem, can't return tooBig */ |
} |
else |
{ |
LWIP_DEBUGF(SNMP_MSG_DEBUG, ( "snmp_msg_event = %" S32_F "\n" ,msg_ps->error_status)); |
} |
/* free varbinds (if available) */ |
snmp_varbind_list_free(&msg_ps->invb); |
snmp_varbind_list_free(&msg_ps->outvb); |
msg_ps->state = SNMP_MSG_EMPTY; |
} |
/** |
* Service an internal or external event for SNMP GET. |
* |
* @param request_id identifies requests from 0 to (SNMP_CONCURRENT_REQUESTS-1) |
* @param msg_ps points to the assosicated message process state |
*/ |
static void |
snmp_msg_get_event(u8_t request_id, struct snmp_msg_pstat *msg_ps) |
{ |
LWIP_DEBUGF(SNMP_MSG_DEBUG, ( "snmp_msg_get_event: msg_ps->state==%" U16_F "\n" ,(u16_t)msg_ps->state)); |
if (msg_ps->state == SNMP_MSG_EXTERNAL_GET_OBJDEF) |
{ |
struct mib_external_node *en; |
struct snmp_name_ptr np; |
/* get_object_def() answer*/ |
en = msg_ps->ext_mib_node; |
np = msg_ps->ext_name_ptr; |
/* translate answer into a known lifeform */ |
en->get_object_def_a(request_id, np.ident_len, np.ident, &msg_ps->ext_object_def); |
if (msg_ps->ext_object_def.instance != MIB_OBJECT_NONE) |
{ |
msg_ps->state = SNMP_MSG_EXTERNAL_GET_VALUE; |
en->get_value_q(request_id, &msg_ps->ext_object_def); |
} |
else |
{ |
en->get_object_def_pc(request_id, np.ident_len, np.ident); |
/* search failed, object id points to unknown object (nosuchname) */ |
snmp_error_response(msg_ps,SNMP_ES_NOSUCHNAME); |
} |
} |
else if (msg_ps->state == SNMP_MSG_EXTERNAL_GET_VALUE) |
{ |
struct mib_external_node *en; |
struct snmp_varbind *vb; |
/* get_value() answer */ |
en = msg_ps->ext_mib_node; |
/* allocate output varbind */ |
vb = ( struct snmp_varbind *)mem_malloc( sizeof ( struct snmp_varbind)); |
LWIP_ASSERT( "vb != NULL" ,vb != NULL); |
if (vb != NULL) |
{ |
vb->next = NULL; |
vb->prev = NULL; |
/* move name from invb to outvb */ |
vb->ident = msg_ps->vb_ptr->ident; |
vb->ident_len = msg_ps->vb_ptr->ident_len; |
/* ensure this memory is refereced once only */ |
msg_ps->vb_ptr->ident = NULL; |
msg_ps->vb_ptr->ident_len = 0; |
vb->value_type = msg_ps->ext_object_def.asn_type; |
vb->value_len = msg_ps->ext_object_def.v_len; |
if (vb->value_len > 0) |
{ |
vb->value = mem_malloc(vb->value_len); |
LWIP_ASSERT( "vb->value != NULL" ,vb->value != NULL); |
if (vb->value != NULL) |
{ |
en->get_value_a(request_id, &msg_ps->ext_object_def, vb->value_len, vb->value); |
snmp_varbind_tail_add(&msg_ps->outvb, vb); |
/* search again (if vb_idx < msg_ps->invb.count) */ |
msg_ps->state = SNMP_MSG_SEARCH_OBJ; |
msg_ps->vb_idx += 1; |
} |
else |
{ |
en->get_value_pc(request_id, &msg_ps->ext_object_def); |
LWIP_DEBUGF(SNMP_MSG_DEBUG, ( "snmp_msg_event: no variable space\n" )); |
msg_ps->vb_ptr->ident = vb->ident; |
msg_ps->vb_ptr->ident_len = vb->ident_len; |
mem_free(vb); |
snmp_error_response(msg_ps,SNMP_ES_TOOBIG); |
} |
} |
else |
{ |
/* vb->value_len == 0, empty value (e.g. empty string) */ |
en->get_value_a(request_id, &msg_ps->ext_object_def, 0, NULL); |
vb->value = NULL; |
snmp_varbind_tail_add(&msg_ps->outvb, vb); |
/* search again (if vb_idx < msg_ps->invb.count) */ |
msg_ps->state = SNMP_MSG_SEARCH_OBJ; |
msg_ps->vb_idx += 1; |
} |
} |
else |
{ |
en->get_value_pc(request_id, &msg_ps->ext_object_def); |
LWIP_DEBUGF(SNMP_MSG_DEBUG, ( "snmp_msg_event: no outvb space\n" )); |
snmp_error_response(msg_ps,SNMP_ES_TOOBIG); |
} |
} |
while ((msg_ps->state == SNMP_MSG_SEARCH_OBJ) && |
(msg_ps->vb_idx < msg_ps->invb.count)) |
{ |
struct mib_node *mn; |
struct snmp_name_ptr np; |
if (msg_ps->vb_idx == 0) |
{ |
msg_ps->vb_ptr = msg_ps->invb.head; |
} |
else |
{ |
msg_ps->vb_ptr = msg_ps->vb_ptr->next; |
} |
/** test object identifier for .iso.org.dod.internet prefix */ |
if (snmp_iso_prefix_tst(msg_ps->vb_ptr->ident_len, msg_ps->vb_ptr->ident)) |
{ |
mn = snmp_search_tree(( struct mib_node*)&internet, msg_ps->vb_ptr->ident_len - 4, |
msg_ps->vb_ptr->ident + 4, &np); |
if (mn != NULL) |
{ |
if (mn->node_type == MIB_NODE_EX) |
{ |
/* external object */ |
struct mib_external_node *en = ( struct mib_external_node*)mn; |
msg_ps->state = SNMP_MSG_EXTERNAL_GET_OBJDEF; |
/* save en && args in msg_ps!! */ |
msg_ps->ext_mib_node = en; |
msg_ps->ext_name_ptr = np; |
en->get_object_def_q(en->addr_inf, request_id, np.ident_len, np.ident); |
} |
else |
{ |
/* internal object */ |
struct obj_def object_def; |
msg_ps->state = SNMP_MSG_INTERNAL_GET_OBJDEF; |
mn->get_object_def(np.ident_len, np.ident, &object_def); |
if (object_def.instance != MIB_OBJECT_NONE) |
{ |
mn = mn; |
} |
else |
{ |
/* search failed, object id points to unknown object (nosuchname) */ |
mn = NULL; |
} |
if (mn != NULL) |
{ |
struct snmp_varbind *vb; |
msg_ps->state = SNMP_MSG_INTERNAL_GET_VALUE; |
/* allocate output varbind */ |
vb = ( struct snmp_varbind *)mem_malloc( sizeof ( struct snmp_varbind)); |
LWIP_ASSERT( "vb != NULL" ,vb != NULL); |
if (vb != NULL) |
{ |
vb->next = NULL; |
vb->prev = NULL; |
/* move name from invb to outvb */ |
vb->ident = msg_ps->vb_ptr->ident; |
vb->ident_len = msg_ps->vb_ptr->ident_len; |
/* ensure this memory is refereced once only */ |
msg_ps->vb_ptr->ident = NULL; |
msg_ps->vb_ptr->ident_len = 0; |
vb->value_type = object_def.asn_type; |
vb->value_len = object_def.v_len; |
if (vb->value_len > 0) |
{ |
vb->value = mem_malloc(vb->value_len); |
LWIP_ASSERT( "vb->value != NULL" ,vb->value != NULL); |
if (vb->value != NULL) |
{ |
mn->get_value(&object_def, vb->value_len, vb->value); |
snmp_varbind_tail_add(&msg_ps->outvb, vb); |
msg_ps->state = SNMP_MSG_SEARCH_OBJ; |
msg_ps->vb_idx += 1; |
} |
else |
{ |
LWIP_DEBUGF(SNMP_MSG_DEBUG, ( "snmp_msg_event: couldn't allocate variable space\n" )); |
msg_ps->vb_ptr->ident = vb->ident; |
msg_ps->vb_ptr->ident_len = vb->ident_len; |
mem_free(vb); |
snmp_error_response(msg_ps,SNMP_ES_TOOBIG); |
} |
} |
else |
{ |
/* vb->value_len == 0, empty value (e.g. empty string) */ |
vb->value = NULL; |
snmp_varbind_tail_add(&msg_ps->outvb, vb); |
msg_ps->state = SNMP_MSG_SEARCH_OBJ; |
msg_ps->vb_idx += 1; |
} |
} |
else |
{ |
LWIP_DEBUGF(SNMP_MSG_DEBUG, ( "snmp_msg_event: couldn't allocate outvb space\n" )); |
snmp_error_response(msg_ps,SNMP_ES_TOOBIG); |
} |
} |
} |
} |
} |
else |
{ |
mn = NULL; |
} |
if (mn == NULL) |
{ |
/* mn == NULL, noSuchName */ |
snmp_error_response(msg_ps,SNMP_ES_NOSUCHNAME); |
} |
} |
if ((msg_ps->state == SNMP_MSG_SEARCH_OBJ) && |
(msg_ps->vb_idx == msg_ps->invb.count)) |
{ |
snmp_ok_response(msg_ps); |
} |
} |
/** |
* Service an internal or external event for SNMP GETNEXT. |
* |
* @param request_id identifies requests from 0 to (SNMP_CONCURRENT_REQUESTS-1) |
* @param msg_ps points to the assosicated message process state |
*/ |
static void |
snmp_msg_getnext_event(u8_t request_id, struct snmp_msg_pstat *msg_ps) |
{ |
LWIP_DEBUGF(SNMP_MSG_DEBUG, ( "snmp_msg_getnext_event: msg_ps->state==%" U16_F "\n" ,(u16_t)msg_ps->state)); |
if (msg_ps->state == SNMP_MSG_EXTERNAL_GET_OBJDEF) |
{ |
struct mib_external_node *en; |
/* get_object_def() answer*/ |
en = msg_ps->ext_mib_node; |
/* translate answer into a known lifeform */ |
en->get_object_def_a(request_id, 1, &msg_ps->ext_oid.id[msg_ps->ext_oid.len - 1], &msg_ps->ext_object_def); |
if (msg_ps->ext_object_def.instance != MIB_OBJECT_NONE) |
{ |
msg_ps->state = SNMP_MSG_EXTERNAL_GET_VALUE; |
en->get_value_q(request_id, &msg_ps->ext_object_def); |
} |
else |
{ |
en->get_object_def_pc(request_id, 1, &msg_ps->ext_oid.id[msg_ps->ext_oid.len - 1]); |
/* search failed, object id points to unknown object (nosuchname) */ |
snmp_error_response(msg_ps,SNMP_ES_NOSUCHNAME); |
} |
} |
else if (msg_ps->state == SNMP_MSG_EXTERNAL_GET_VALUE) |
{ |
struct mib_external_node *en; |
struct snmp_varbind *vb; |
/* get_value() answer */ |
en = msg_ps->ext_mib_node; |
vb = snmp_varbind_alloc(&msg_ps->ext_oid, |
msg_ps->ext_object_def.asn_type, |
msg_ps->ext_object_def.v_len); |
if (vb != NULL) |
{ |
en->get_value_a(request_id, &msg_ps->ext_object_def, vb->value_len, vb->value); |
snmp_varbind_tail_add(&msg_ps->outvb, vb); |
msg_ps->state = SNMP_MSG_SEARCH_OBJ; |
msg_ps->vb_idx += 1; |
} |
else |
{ |
en->get_value_pc(request_id, &msg_ps->ext_object_def); |
LWIP_DEBUGF(SNMP_MSG_DEBUG, ( "snmp_msg_getnext_event: couldn't allocate outvb space\n" )); |
snmp_error_response(msg_ps,SNMP_ES_TOOBIG); |
} |
} |
while ((msg_ps->state == SNMP_MSG_SEARCH_OBJ) && |
(msg_ps->vb_idx < msg_ps->invb.count)) |
{ |
struct mib_node *mn; |
struct snmp_obj_id oid; |
if (msg_ps->vb_idx == 0) |
{ |
msg_ps->vb_ptr = msg_ps->invb.head; |
} |
else |
{ |
msg_ps->vb_ptr = msg_ps->vb_ptr->next; |
} |
if (snmp_iso_prefix_expand(msg_ps->vb_ptr->ident_len, msg_ps->vb_ptr->ident, &oid)) |
{ |
if (msg_ps->vb_ptr->ident_len > 3) |
{ |
/* can offset ident_len and ident */ |
mn = snmp_expand_tree(( struct mib_node*)&internet, |
msg_ps->vb_ptr->ident_len - 4, |
msg_ps->vb_ptr->ident + 4, &oid); |
} |
else |
{ |
/* can't offset ident_len -4, ident + 4 */ |
mn = snmp_expand_tree(( struct mib_node*)&internet, 0, NULL, &oid); |
} |
} |
else |
{ |
mn = NULL; |
} |
if (mn != NULL) |
{ |
if (mn->node_type == MIB_NODE_EX) |
{ |
/* external object */ |
struct mib_external_node *en = ( struct mib_external_node*)mn; |
msg_ps->state = SNMP_MSG_EXTERNAL_GET_OBJDEF; |
/* save en && args in msg_ps!! */ |
msg_ps->ext_mib_node = en; |
msg_ps->ext_oid = oid; |
en->get_object_def_q(en->addr_inf, request_id, 1, &oid.id[oid.len - 1]); |
} |
else |
{ |
/* internal object */ |
struct obj_def object_def; |
struct snmp_varbind *vb; |
msg_ps->state = SNMP_MSG_INTERNAL_GET_OBJDEF; |
mn->get_object_def(1, &oid.id[oid.len - 1], &object_def); |
vb = snmp_varbind_alloc(&oid, object_def.asn_type, object_def.v_len); |
if (vb != NULL) |
{ |
msg_ps->state = SNMP_MSG_INTERNAL_GET_VALUE; |
mn->get_value(&object_def, object_def.v_len, vb->value); |
snmp_varbind_tail_add(&msg_ps->outvb, vb); |
msg_ps->state = SNMP_MSG_SEARCH_OBJ; |
msg_ps->vb_idx += 1; |
} |
else |
{ |
LWIP_DEBUGF(SNMP_MSG_DEBUG, ( "snmp_recv couldn't allocate outvb space\n" )); |
snmp_error_response(msg_ps,SNMP_ES_TOOBIG); |
} |
} |
} |
if (mn == NULL) |
{ |
/* mn == NULL, noSuchName */ |
snmp_error_response(msg_ps,SNMP_ES_NOSUCHNAME); |
} |
} |
if ((msg_ps->state == SNMP_MSG_SEARCH_OBJ) && |
(msg_ps->vb_idx == msg_ps->invb.count)) |
{ |
snmp_ok_response(msg_ps); |
} |
} |
/** |
* Service an internal or external event for SNMP SET. |
* |
* @param request_id identifies requests from 0 to (SNMP_CONCURRENT_REQUESTS-1) |
* @param msg_ps points to the assosicated message process state |
*/ |
static void |
snmp_msg_set_event(u8_t request_id, struct snmp_msg_pstat *msg_ps) |
{ |
LWIP_DEBUGF(SNMP_MSG_DEBUG, ( "snmp_msg_set_event: msg_ps->state==%" U16_F "\n" ,(u16_t)msg_ps->state)); |
if (msg_ps->state == SNMP_MSG_EXTERNAL_GET_OBJDEF) |
{ |
struct mib_external_node *en; |
struct snmp_name_ptr np; |
/* get_object_def() answer*/ |
en = msg_ps->ext_mib_node; |
np = msg_ps->ext_name_ptr; |
/* translate answer into a known lifeform */ |
en->get_object_def_a(request_id, np.ident_len, np.ident, &msg_ps->ext_object_def); |
if (msg_ps->ext_object_def.instance != MIB_OBJECT_NONE) |
{ |
msg_ps->state = SNMP_MSG_EXTERNAL_SET_TEST; |
en->set_test_q(request_id, &msg_ps->ext_object_def); |
} |
else |
{ |
en->get_object_def_pc(request_id, np.ident_len, np.ident); |
/* search failed, object id points to unknown object (nosuchname) */ |
snmp_error_response(msg_ps,SNMP_ES_NOSUCHNAME); |
} |
} |
else if (msg_ps->state == SNMP_MSG_EXTERNAL_SET_TEST) |
{ |
struct mib_external_node *en; |
/* set_test() answer*/ |
en = msg_ps->ext_mib_node; |
if (msg_ps->ext_object_def.access == MIB_OBJECT_READ_WRITE) |
{ |
if ((msg_ps->ext_object_def.asn_type == msg_ps->vb_ptr->value_type) && |
(en->set_test_a(request_id,&msg_ps->ext_object_def, |
msg_ps->vb_ptr->value_len,msg_ps->vb_ptr->value) != 0)) |
{ |
msg_ps->state = SNMP_MSG_SEARCH_OBJ; |
msg_ps->vb_idx += 1; |
} |
else |
{ |
en->set_test_pc(request_id,&msg_ps->ext_object_def); |
/* bad value */ |
snmp_error_response(msg_ps,SNMP_ES_BADVALUE); |
} |
} |
else |
{ |
en->set_test_pc(request_id,&msg_ps->ext_object_def); |
/* object not available for set */ |
snmp_error_response(msg_ps,SNMP_ES_NOSUCHNAME); |
} |
} |
else if (msg_ps->state == SNMP_MSG_EXTERNAL_GET_OBJDEF_S) |
{ |
struct mib_external_node *en; |
struct snmp_name_ptr np; |
/* get_object_def() answer*/ |
en = msg_ps->ext_mib_node; |
np = msg_ps->ext_name_ptr; |
/* translate answer into a known lifeform */ |
en->get_object_def_a(request_id, np.ident_len, np.ident, &msg_ps->ext_object_def); |
if (msg_ps->ext_object_def.instance != MIB_OBJECT_NONE) |
{ |
msg_ps->state = SNMP_MSG_EXTERNAL_SET_VALUE; |
en->set_value_q(request_id, &msg_ps->ext_object_def, |
msg_ps->vb_ptr->value_len,msg_ps->vb_ptr->value); |
} |
else |
{ |
en->get_object_def_pc(request_id, np.ident_len, np.ident); |
/* set_value failed, object has disappeared for some odd reason?? */ |
snmp_error_response(msg_ps,SNMP_ES_GENERROR); |
} |
} |
else if (msg_ps->state == SNMP_MSG_EXTERNAL_SET_VALUE) |
{ |
struct mib_external_node *en; |
/** set_value_a() */ |
en = msg_ps->ext_mib_node; |
en->set_value_a(request_id, &msg_ps->ext_object_def, |
msg_ps->vb_ptr->value_len, msg_ps->vb_ptr->value); |
/** @todo use set_value_pc() if toobig */ |
msg_ps->state = SNMP_MSG_INTERNAL_SET_VALUE; |
msg_ps->vb_idx += 1; |
} |
/* test all values before setting */ |
while ((msg_ps->state == SNMP_MSG_SEARCH_OBJ) && |
(msg_ps->vb_idx < msg_ps->invb.count)) |
{ |
struct mib_node *mn; |
struct snmp_name_ptr np; |
if (msg_ps->vb_idx == 0) |
{ |
msg_ps->vb_ptr = msg_ps->invb.head; |
} |
else |
{ |
msg_ps->vb_ptr = msg_ps->vb_ptr->next; |
} |
/** test object identifier for .iso.org.dod.internet prefix */ |
if (snmp_iso_prefix_tst(msg_ps->vb_ptr->ident_len, msg_ps->vb_ptr->ident)) |
{ |
mn = snmp_search_tree(( struct mib_node*)&internet, msg_ps->vb_ptr->ident_len - 4, |
msg_ps->vb_ptr->ident + 4, &np); |
if (mn != NULL) |
{ |
if (mn->node_type == MIB_NODE_EX) |
{ |
/* external object */ |
struct mib_external_node *en = ( struct mib_external_node*)mn; |
msg_ps->state = SNMP_MSG_EXTERNAL_GET_OBJDEF; |
/* save en && args in msg_ps!! */ |
msg_ps->ext_mib_node = en; |
msg_ps->ext_name_ptr = np; |
en->get_object_def_q(en->addr_inf, request_id, np.ident_len, np.ident); |
} |
else |
{ |
/* internal object */ |
struct obj_def object_def; |
msg_ps->state = SNMP_MSG_INTERNAL_GET_OBJDEF; |
mn->get_object_def(np.ident_len, np.ident, &object_def); |
if (object_def.instance != MIB_OBJECT_NONE) |
{ |
mn = mn; |
} |
else |
{ |
/* search failed, object id points to unknown object (nosuchname) */ |
mn = NULL; |
} |
if (mn != NULL) |
{ |
msg_ps->state = SNMP_MSG_INTERNAL_SET_TEST; |
if (object_def.access == MIB_OBJECT_READ_WRITE) |
{ |
if ((object_def.asn_type == msg_ps->vb_ptr->value_type) && |
(mn->set_test(&object_def,msg_ps->vb_ptr->value_len,msg_ps->vb_ptr->value) != 0)) |
{ |
msg_ps->state = SNMP_MSG_SEARCH_OBJ; |
msg_ps->vb_idx += 1; |
} |
else |
{ |
/* bad value */ |
snmp_error_response(msg_ps,SNMP_ES_BADVALUE); |
} |
} |
else |
{ |
/* object not available for set */ |
snmp_error_response(msg_ps,SNMP_ES_NOSUCHNAME); |
} |
} |
} |
} |
} |
else |
{ |
mn = NULL; |
} |
if (mn == NULL) |
{ |
/* mn == NULL, noSuchName */ |
snmp_error_response(msg_ps,SNMP_ES_NOSUCHNAME); |
} |
} |
if ((msg_ps->state == SNMP_MSG_SEARCH_OBJ) && |
(msg_ps->vb_idx == msg_ps->invb.count)) |
{ |
msg_ps->vb_idx = 0; |
msg_ps->state = SNMP_MSG_INTERNAL_SET_VALUE; |
} |
/* set all values "atomically" (be as "atomic" as possible) */ |
while ((msg_ps->state == SNMP_MSG_INTERNAL_SET_VALUE) && |
(msg_ps->vb_idx < msg_ps->invb.count)) |
{ |
struct mib_node *mn; |
struct snmp_name_ptr np; |
if (msg_ps->vb_idx == 0) |
{ |
msg_ps->vb_ptr = msg_ps->invb.head; |
} |
else |
{ |
msg_ps->vb_ptr = msg_ps->vb_ptr->next; |
} |
/* skip iso prefix test, was done previously while settesting() */ |
mn = snmp_search_tree(( struct mib_node*)&internet, msg_ps->vb_ptr->ident_len - 4, |
msg_ps->vb_ptr->ident + 4, &np); |
/* check if object is still available |
(e.g. external hot-plug thingy present?) */ |
if (mn != NULL) |
{ |
if (mn->node_type == MIB_NODE_EX) |
{ |
/* external object */ |
struct mib_external_node *en = ( struct mib_external_node*)mn; |
msg_ps->state = SNMP_MSG_EXTERNAL_GET_OBJDEF_S; |
/* save en && args in msg_ps!! */ |
msg_ps->ext_mib_node = en; |
msg_ps->ext_name_ptr = np; |
en->get_object_def_q(en->addr_inf, request_id, np.ident_len, np.ident); |
} |
else |
{ |
/* internal object */ |
struct obj_def object_def; |
msg_ps->state = SNMP_MSG_INTERNAL_GET_OBJDEF_S; |
mn->get_object_def(np.ident_len, np.ident, &object_def); |
msg_ps->state = SNMP_MSG_INTERNAL_SET_VALUE; |
mn->set_value(&object_def,msg_ps->vb_ptr->value_len,msg_ps->vb_ptr->value); |
msg_ps->vb_idx += 1; |
} |
} |
} |
if ((msg_ps->state == SNMP_MSG_INTERNAL_SET_VALUE) && |
(msg_ps->vb_idx == msg_ps->invb.count)) |
{ |
/* simply echo the input if we can set it |
@todo do we need to return the actual value? |
e.g. if value is silently modified or behaves sticky? */ |
msg_ps->outvb = msg_ps->invb; |
msg_ps->invb.head = NULL; |
msg_ps->invb.tail = NULL; |
msg_ps->invb.count = 0; |
snmp_ok_response(msg_ps); |
} |
} |
/** |
* Handle one internal or external event. |
* Called for one async event. (recv external/private answer) |
* |
* @param request_id identifies requests from 0 to (SNMP_CONCURRENT_REQUESTS-1) |
*/ |
void |
snmp_msg_event(u8_t request_id) |
{ |
struct snmp_msg_pstat *msg_ps; |
if (request_id < SNMP_CONCURRENT_REQUESTS) |
{ |
msg_ps = &msg_input_list[request_id]; |
if (msg_ps->rt == SNMP_ASN1_PDU_GET_NEXT_REQ) |
{ |
snmp_msg_getnext_event(request_id, msg_ps); |
} |
else if (msg_ps->rt == SNMP_ASN1_PDU_GET_REQ) |
{ |
snmp_msg_get_event(request_id, msg_ps); |
} |
else if (msg_ps->rt == SNMP_ASN1_PDU_SET_REQ) |
{ |
snmp_msg_set_event(request_id, msg_ps); |
} |
} |
} |
/* lwIP UDP receive callback function */ |
static void |
snmp_recv( void *arg, struct udp_pcb *pcb, struct pbuf *p, struct ip_addr *addr, u16_t port) |
{ |
struct udp_hdr *udphdr; |
/* suppress unused argument warning */ |
LWIP_UNUSED_ARG(arg); |
/* peek in the UDP header (goto IP payload) */ |
if (pbuf_header(p, UDP_HLEN)){ |
LWIP_ASSERT( "Can't move to UDP header" , 0); |
pbuf_free(p); |
return ; |
} |
udphdr = p->payload; |
/* check if datagram is really directed at us (including broadcast requests) */ |
if ((pcb == snmp1_pcb) && (ntohs(udphdr->dest) == SNMP_IN_PORT)) |
{ |
struct snmp_msg_pstat *msg_ps; |
u8_t req_idx; |
/* traverse input message process list, look for SNMP_MSG_EMPTY */ |
msg_ps = &msg_input_list[0]; |
req_idx = 0; |
while ((req_idx<SNMP_CONCURRENT_REQUESTS) && (msg_ps->state != SNMP_MSG_EMPTY)) |
{ |
req_idx++; |
msg_ps++; |
} |
if (req_idx != SNMP_CONCURRENT_REQUESTS) |
{ |
err_t err_ret; |
u16_t payload_len; |
u16_t payload_ofs; |
u16_t varbind_ofs = 0; |
/* accepting request */ |
snmp_inc_snmpinpkts(); |
/* record used 'protocol control block' */ |
msg_ps->pcb = pcb; |
/* source address (network order) */ |
msg_ps->sip = *addr; |
/* source port (host order (lwIP oddity)) */ |
msg_ps->sp = port; |
/* read UDP payload length from UDP header */ |
payload_len = ntohs(udphdr->len) - UDP_HLEN; |
/* adjust to UDP payload */ |
payload_ofs = UDP_HLEN; |
/* check total length, version, community, pdu type */ |
err_ret = snmp_pdu_header_check(p, payload_ofs, payload_len, &varbind_ofs, msg_ps); |
if (((msg_ps->rt == SNMP_ASN1_PDU_GET_REQ) || |
(msg_ps->rt == SNMP_ASN1_PDU_GET_NEXT_REQ) || |
(msg_ps->rt == SNMP_ASN1_PDU_SET_REQ)) && |
((msg_ps->error_status == SNMP_ES_NOERROR) && |
(msg_ps->error_index == 0)) ) |
{ |
/* Only accept requests and requests without error (be robust) */ |
err_ret = err_ret; |
} |
else |
{ |
/* Reject response and trap headers or error requests as input! */ |
err_ret = ERR_ARG; |
} |
if (err_ret == ERR_OK) |
{ |
LWIP_DEBUGF(SNMP_MSG_DEBUG, ( "snmp_recv ok, community %s\n" , msg_ps->community)); |
/* Builds a list of variable bindings. Copy the varbinds from the pbuf |
chain to glue them when these are divided over two or more pbuf's. */ |
err_ret = snmp_pdu_dec_varbindlist(p, varbind_ofs, &varbind_ofs, msg_ps); |
if ((err_ret == ERR_OK) && (msg_ps->invb.count > 0)) |
{ |
/* we've decoded the incoming message, release input msg now */ |
pbuf_free(p); |
msg_ps->error_status = SNMP_ES_NOERROR; |
msg_ps->error_index = 0; |
/* find object for each variable binding */ |
msg_ps->state = SNMP_MSG_SEARCH_OBJ; |
/* first variable binding from list to inspect */ |
msg_ps->vb_idx = 0; |
LWIP_DEBUGF(SNMP_MSG_DEBUG, ( "snmp_recv varbind cnt=%" U16_F "\n" ,(u16_t)msg_ps->invb.count)); |
/* handle input event and as much objects as possible in one go */ |
snmp_msg_event(req_idx); |
} |
else |
{ |
/* varbind-list decode failed, or varbind list empty. |
drop request silently, do not return error! |
(errors are only returned for a specific varbind failure) */ |
pbuf_free(p); |
LWIP_DEBUGF(SNMP_MSG_DEBUG, ( "snmp_pdu_dec_varbindlist() failed\n" )); |
} |
} |
else |
{ |
/* header check failed |
drop request silently, do not return error! */ |
pbuf_free(p); |
LWIP_DEBUGF(SNMP_MSG_DEBUG, ( "snmp_pdu_header_check() failed\n" )); |
} |
} |
else |
{ |
/* exceeding number of concurrent requests */ |
pbuf_free(p); |
} |
} |
else |
{ |
/* datagram not for us */ |
pbuf_free(p); |
} |
} |
/** |
* Checks and decodes incoming SNMP message header, logs header errors. |
* |
* @param p points to pbuf chain of SNMP message (UDP payload) |
* @param ofs points to first octet of SNMP message |
* @param pdu_len the length of the UDP payload |
* @param ofs_ret returns the ofset of the variable bindings |
* @param m_stat points to the current message request state return |
* @return |
* - ERR_OK SNMP header is sane and accepted |
* - ERR_ARG SNMP header is either malformed or rejected |
*/ |
static err_t |
snmp_pdu_header_check( struct pbuf *p, u16_t ofs, u16_t pdu_len, u16_t *ofs_ret, struct snmp_msg_pstat *m_stat) |
{ |
err_t derr; |
u16_t len, ofs_base; |
u8_t len_octets; |
u8_t type; |
s32_t version; |
ofs_base = ofs; |
snmp_asn1_dec_type(p, ofs, &type); |
derr = snmp_asn1_dec_length(p, ofs+1, &len_octets, &len); |
if ((derr != ERR_OK) || |
(pdu_len != (1 + len_octets + len)) || |
(type != (SNMP_ASN1_UNIV | SNMP_ASN1_CONSTR | SNMP_ASN1_SEQ))) |
{ |
snmp_inc_snmpinasnparseerrs(); |
return ERR_ARG; |
} |
ofs += (1 + len_octets); |
snmp_asn1_dec_type(p, ofs, &type); |
derr = snmp_asn1_dec_length(p, ofs+1, &len_octets, &len); |
if ((derr != ERR_OK) || (type != (SNMP_ASN1_UNIV | SNMP_ASN1_PRIMIT | SNMP_ASN1_INTEG))) |
{ |
/* can't decode or no integer (version) */ |
snmp_inc_snmpinasnparseerrs(); |
return ERR_ARG; |
} |
derr = snmp_asn1_dec_s32t(p, ofs + 1 + len_octets, len, &version); |
if (derr != ERR_OK) |
{ |
/* can't decode */ |
snmp_inc_snmpinasnparseerrs(); |
return ERR_ARG; |
} |
if (version != 0) |
{ |
/* not version 1 */ |
snmp_inc_snmpinbadversions(); |
return ERR_ARG; |
} |
ofs += (1 + len_octets + len); |
snmp_asn1_dec_type(p, ofs, &type); |
derr = snmp_asn1_dec_length(p, ofs+1, &len_octets, &len); |
if ((derr != ERR_OK) || (type != (SNMP_ASN1_UNIV | SNMP_ASN1_PRIMIT | SNMP_ASN1_OC_STR))) |
{ |
/* can't decode or no octet string (community) */ |
snmp_inc_snmpinasnparseerrs(); |
return ERR_ARG; |
} |
derr = snmp_asn1_dec_raw(p, ofs + 1 + len_octets, len, SNMP_COMMUNITY_STR_LEN, m_stat->community); |
if (derr != ERR_OK) |
{ |
snmp_inc_snmpinasnparseerrs(); |
return ERR_ARG; |
} |
/* add zero terminator */ |
len = ((len < (SNMP_COMMUNITY_STR_LEN))?(len):(SNMP_COMMUNITY_STR_LEN)); |
m_stat->community[len] = 0; |
m_stat->com_strlen = len; |
if ( strncmp (snmp_publiccommunity, ( const char *)m_stat->community, SNMP_COMMUNITY_STR_LEN) != 0) |
{ |
/** @todo: move this if we need to check more names */ |
snmp_inc_snmpinbadcommunitynames(); |
snmp_authfail_trap(); |
return ERR_ARG; |
} |
ofs += (1 + len_octets + len); |
snmp_asn1_dec_type(p, ofs, &type); |
derr = snmp_asn1_dec_length(p, ofs+1, &len_octets, &len); |
if (derr != ERR_OK) |
{ |
snmp_inc_snmpinasnparseerrs(); |
return ERR_ARG; |
} |
switch (type) |
{ |
case (SNMP_ASN1_CONTXT | SNMP_ASN1_CONSTR | SNMP_ASN1_PDU_GET_REQ): |
/* GetRequest PDU */ |
snmp_inc_snmpingetrequests(); |
derr = ERR_OK; |
break ; |
case (SNMP_ASN1_CONTXT | SNMP_ASN1_CONSTR | SNMP_ASN1_PDU_GET_NEXT_REQ): |
/* GetNextRequest PDU */ |
snmp_inc_snmpingetnexts(); |
derr = ERR_OK; |
break ; |
case (SNMP_ASN1_CONTXT | SNMP_ASN1_CONSTR | SNMP_ASN1_PDU_GET_RESP): |
/* GetResponse PDU */ |
snmp_inc_snmpingetresponses(); |
derr = ERR_ARG; |
break ; |
case (SNMP_ASN1_CONTXT | SNMP_ASN1_CONSTR | SNMP_ASN1_PDU_SET_REQ): |
/* SetRequest PDU */ |
snmp_inc_snmpinsetrequests(); |
derr = ERR_OK; |
break ; |
case (SNMP_ASN1_CONTXT | SNMP_ASN1_CONSTR | SNMP_ASN1_PDU_TRAP): |
/* Trap PDU */ |
snmp_inc_snmpintraps(); |
derr = ERR_ARG; |
break ; |
default : |
snmp_inc_snmpinasnparseerrs(); |
derr = ERR_ARG; |
break ; |
} |
if (derr != ERR_OK) |
{ |
/* unsupported input PDU for this agent (no parse error) */ |
return ERR_ARG; |
} |
m_stat->rt = type & 0x1F; |
ofs += (1 + len_octets); |
if (len != (pdu_len - (ofs - ofs_base))) |
{ |
/* decoded PDU length does not equal actual payload length */ |
snmp_inc_snmpinasnparseerrs(); |
return ERR_ARG; |
} |
snmp_asn1_dec_type(p, ofs, &type); |
derr = snmp_asn1_dec_length(p, ofs+1, &len_octets, &len); |
if ((derr != ERR_OK) || (type != (SNMP_ASN1_UNIV | SNMP_ASN1_PRIMIT | SNMP_ASN1_INTEG))) |
{ |
/* can't decode or no integer (request ID) */ |
snmp_inc_snmpinasnparseerrs(); |
return ERR_ARG; |
} |
derr = snmp_asn1_dec_s32t(p, ofs + 1 + len_octets, len, &m_stat->rid); |
if (derr != ERR_OK) |
{ |
/* can't decode */ |
snmp_inc_snmpinasnparseerrs(); |
return ERR_ARG; |
} |
ofs += (1 + len_octets + len); |
snmp_asn1_dec_type(p, ofs, &type); |
derr = snmp_asn1_dec_length(p, ofs+1, &len_octets, &len); |
if ((derr != ERR_OK) || (type != (SNMP_ASN1_UNIV | SNMP_ASN1_PRIMIT | SNMP_ASN1_INTEG))) |
{ |
/* can't decode or no integer (error-status) */ |
snmp_inc_snmpinasnparseerrs(); |
return ERR_ARG; |
} |
/* must be noError (0) for incoming requests. |
log errors for mib-2 completeness and for debug purposes */ |
derr = snmp_asn1_dec_s32t(p, ofs + 1 + len_octets, len, &m_stat->error_status); |
if (derr != ERR_OK) |
{ |
/* can't decode */ |
snmp_inc_snmpinasnparseerrs(); |
return ERR_ARG; |
} |
switch (m_stat->error_status) |
{ |
case SNMP_ES_TOOBIG: |
snmp_inc_snmpintoobigs(); |
break ; |
case SNMP_ES_NOSUCHNAME: |
snmp_inc_snmpinnosuchnames(); |
break ; |
case SNMP_ES_BADVALUE: |
snmp_inc_snmpinbadvalues(); |
break ; |
case SNMP_ES_READONLY: |
snmp_inc_snmpinreadonlys(); |
break ; |
case SNMP_ES_GENERROR: |
snmp_inc_snmpingenerrs(); |
break ; |
} |
ofs += (1 + len_octets + len); |
snmp_asn1_dec_type(p, ofs, &type); |
derr = snmp_asn1_dec_length(p, ofs+1, &len_octets, &len); |
if ((derr != ERR_OK) || (type != (SNMP_ASN1_UNIV | SNMP_ASN1_PRIMIT | SNMP_ASN1_INTEG))) |
{ |
/* can't decode or no integer (error-index) */ |
snmp_inc_snmpinasnparseerrs(); |
return ERR_ARG; |
} |
/* must be 0 for incoming requests. |
decode anyway to catch bad integers (and dirty tricks) */ |
derr = snmp_asn1_dec_s32t(p, ofs + 1 + len_octets, len, &m_stat->error_index); |
if (derr != ERR_OK) |
{ |
/* can't decode */ |
snmp_inc_snmpinasnparseerrs(); |
return ERR_ARG; |
} |
ofs += (1 + len_octets + len); |
*ofs_ret = ofs; |
return ERR_OK; |
} |
static err_t |
snmp_pdu_dec_varbindlist( struct pbuf *p, u16_t ofs, u16_t *ofs_ret, struct snmp_msg_pstat *m_stat) |
{ |
err_t derr; |
u16_t len, vb_len; |
u8_t len_octets; |
u8_t type; |
/* variable binding list */ |
snmp_asn1_dec_type(p, ofs, &type); |
derr = snmp_asn1_dec_length(p, ofs+1, &len_octets, &vb_len); |
if ((derr != ERR_OK) || |
(type != (SNMP_ASN1_UNIV | SNMP_ASN1_CONSTR | SNMP_ASN1_SEQ))) |
{ |
snmp_inc_snmpinasnparseerrs(); |
return ERR_ARG; |
} |
ofs += (1 + len_octets); |
/* start with empty list */ |
m_stat->invb.count = 0; |
m_stat->invb.head = NULL; |
m_stat->invb.tail = NULL; |
while (vb_len > 0) |
{ |
struct snmp_obj_id oid, oid_value; |
struct snmp_varbind *vb; |
snmp_asn1_dec_type(p, ofs, &type); |
derr = snmp_asn1_dec_length(p, ofs+1, &len_octets, &len); |
if ((derr != ERR_OK) || |
(type != (SNMP_ASN1_UNIV | SNMP_ASN1_CONSTR | SNMP_ASN1_SEQ)) || |
(len == 0) || (len > vb_len)) |
{ |
snmp_inc_snmpinasnparseerrs(); |
/* free varbinds (if available) */ |
snmp_varbind_list_free(&m_stat->invb); |
return ERR_ARG; |
} |
ofs += (1 + len_octets); |
vb_len -= (1 + len_octets); |
snmp_asn1_dec_type(p, ofs, &type); |
derr = snmp_asn1_dec_length(p, ofs+1, &len_octets, &len); |
if ((derr != ERR_OK) || (type != (SNMP_ASN1_UNIV | SNMP_ASN1_PRIMIT | SNMP_ASN1_OBJ_ID))) |
{ |
/* can't decode object name length */ |
snmp_inc_snmpinasnparseerrs(); |
/* free varbinds (if available) */ |
snmp_varbind_list_free(&m_stat->invb); |
return ERR_ARG; |
} |
derr = snmp_asn1_dec_oid(p, ofs + 1 + len_octets, len, &oid); |
if (derr != ERR_OK) |
{ |
/* can't decode object name */ |
snmp_inc_snmpinasnparseerrs(); |
/* free varbinds (if available) */ |
snmp_varbind_list_free(&m_stat->invb); |
return ERR_ARG; |
} |
ofs += (1 + len_octets + len); |
vb_len -= (1 + len_octets + len); |
snmp_asn1_dec_type(p, ofs, &type); |
derr = snmp_asn1_dec_length(p, ofs+1, &len_octets, &len); |
if (derr != ERR_OK) |
{ |
/* can't decode object value length */ |
snmp_inc_snmpinasnparseerrs(); |
/* free varbinds (if available) */ |
snmp_varbind_list_free(&m_stat->invb); |
return ERR_ARG; |
} |
switch (type) |
{ |
case (SNMP_ASN1_UNIV | SNMP_ASN1_PRIMIT | SNMP_ASN1_INTEG): |
vb = snmp_varbind_alloc(&oid, type, sizeof (s32_t)); |
if (vb != NULL) |
{ |
s32_t *vptr = vb->value; |
derr = snmp_asn1_dec_s32t(p, ofs + 1 + len_octets, len, vptr); |
snmp_varbind_tail_add(&m_stat->invb, vb); |
} |
else |
{ |
derr = ERR_ARG; |
} |
break ; |
case (SNMP_ASN1_APPLIC | SNMP_ASN1_PRIMIT | SNMP_ASN1_COUNTER): |
case (SNMP_ASN1_APPLIC | SNMP_ASN1_PRIMIT | SNMP_ASN1_GAUGE): |
case (SNMP_ASN1_APPLIC | SNMP_ASN1_PRIMIT | SNMP_ASN1_TIMETICKS): |
vb = snmp_varbind_alloc(&oid, type, sizeof (u32_t)); |
if (vb != NULL) |
{ |
u32_t *vptr = vb->value; |
derr = snmp_asn1_dec_u32t(p, ofs + 1 + len_octets, len, vptr); |
snmp_varbind_tail_add(&m_stat->invb, vb); |
} |
else |
{ |
derr = ERR_ARG; |
} |
break ; |
case (SNMP_ASN1_UNIV | SNMP_ASN1_PRIMIT | SNMP_ASN1_OC_STR): |
case (SNMP_ASN1_APPLIC | SNMP_ASN1_PRIMIT | SNMP_ASN1_OPAQUE): |
vb = snmp_varbind_alloc(&oid, type, len); |
if (vb != NULL) |
{ |
derr = snmp_asn1_dec_raw(p, ofs + 1 + len_octets, len, vb->value_len, vb->value); |
snmp_varbind_tail_add(&m_stat->invb, vb); |
} |
else |
{ |
derr = ERR_ARG; |
} |
break ; |
case (SNMP_ASN1_UNIV | SNMP_ASN1_PRIMIT | SNMP_ASN1_NUL): |
vb = snmp_varbind_alloc(&oid, type, 0); |
if (vb != NULL) |
{ |
snmp_varbind_tail_add(&m_stat->invb, vb); |
derr = ERR_OK; |
} |
else |
{ |
derr = ERR_ARG; |
} |
break ; |
case (SNMP_ASN1_UNIV | SNMP_ASN1_PRIMIT | SNMP_ASN1_OBJ_ID): |
derr = snmp_asn1_dec_oid(p, ofs + 1 + len_octets, len, &oid_value); |
if (derr == ERR_OK) |
{ |
vb = snmp_varbind_alloc(&oid, type, oid_value.len * sizeof (s32_t)); |
if (vb != NULL) |
{ |
u8_t i = oid_value.len; |
s32_t *vptr = vb->value; |
while (i > 0) |
{ |
i--; |
vptr[i] = oid_value.id[i]; |
} |
snmp_varbind_tail_add(&m_stat->invb, vb); |
derr = ERR_OK; |
} |
else |
{ |
derr = ERR_ARG; |
} |
} |
break ; |
case (SNMP_ASN1_APPLIC | SNMP_ASN1_PRIMIT | SNMP_ASN1_IPADDR): |
if (len == 4) |
{ |
/* must be exactly 4 octets! */ |
vb = snmp_varbind_alloc(&oid, type, 4); |
if (vb != NULL) |
{ |
derr = snmp_asn1_dec_raw(p, ofs + 1 + len_octets, len, vb->value_len, vb->value); |
snmp_varbind_tail_add(&m_stat->invb, vb); |
} |
else |
{ |
derr = ERR_ARG; |
} |
} |
else |
{ |
derr = ERR_ARG; |
} |
break ; |
default : |
derr = ERR_ARG; |
break ; |
} |
if (derr != ERR_OK) |
{ |
snmp_inc_snmpinasnparseerrs(); |
/* free varbinds (if available) */ |
snmp_varbind_list_free(&m_stat->invb); |
return ERR_ARG; |
} |
ofs += (1 + len_octets + len); |
vb_len -= (1 + len_octets + len); |
} |
if (m_stat->rt == SNMP_ASN1_PDU_SET_REQ) |
{ |
snmp_add_snmpintotalsetvars(m_stat->invb.count); |
} |
else |
{ |
snmp_add_snmpintotalreqvars(m_stat->invb.count); |
} |
*ofs_ret = ofs; |
return ERR_OK; |
} |
struct snmp_varbind* |
snmp_varbind_alloc( struct snmp_obj_id *oid, u8_t type, u8_t len) |
{ |
struct snmp_varbind *vb; |
vb = ( struct snmp_varbind *)mem_malloc( sizeof ( struct snmp_varbind)); |
LWIP_ASSERT( "vb != NULL" ,vb != NULL); |
if (vb != NULL) |
{ |
u8_t i; |
vb->next = NULL; |
vb->prev = NULL; |
i = oid->len; |
vb->ident_len = i; |
if (i > 0) |
{ |
/* allocate array of s32_t for our object identifier */ |
vb->ident = (s32_t*)mem_malloc( sizeof (s32_t) * i); |
LWIP_ASSERT( "vb->ident != NULL" ,vb->ident != NULL); |
if (vb->ident == NULL) |
{ |
mem_free(vb); |
return NULL; |
} |
while (i > 0) |
{ |
i--; |
vb->ident[i] = oid->id[i]; |
} |
} |
else |
{ |
/* i == 0, pass zero length object identifier */ |
vb->ident = NULL; |
} |
vb->value_type = type; |
vb->value_len = len; |
if (len > 0) |
{ |
/* allocate raw bytes for our object value */ |
vb->value = mem_malloc(len); |
LWIP_ASSERT( "vb->value != NULL" ,vb->value != NULL); |
if (vb->value == NULL) |
{ |
if (vb->ident != NULL) |
{ |
mem_free(vb->ident); |
} |
mem_free(vb); |
return NULL; |
} |
} |
else |
{ |
/* ASN1_NUL type, or zero length ASN1_OC_STR */ |
vb->value = NULL; |
} |
} |
return vb; |
} |
void |
snmp_varbind_free( struct snmp_varbind *vb) |
{ |
if (vb->value != NULL ) |
{ |
mem_free(vb->value); |
} |
if (vb->ident != NULL ) |
{ |
mem_free(vb->ident); |
} |
mem_free(vb); |
} |
void |
snmp_varbind_list_free( struct snmp_varbind_root *root) |
{ |
struct snmp_varbind *vb, *prev; |
vb = root->tail; |
while ( vb != NULL ) |
{ |
prev = vb->prev; |
snmp_varbind_free(vb); |
vb = prev; |
} |
root->count = 0; |
root->head = NULL; |
root->tail = NULL; |
} |
void |
snmp_varbind_tail_add( struct snmp_varbind_root *root, struct snmp_varbind *vb) |
{ |
if (root->count == 0) |
{ |
/* add first varbind to list */ |
root->head = vb; |
root->tail = vb; |
} |
else |
{ |
/* add nth varbind to list tail */ |
root->tail->next = vb; |
vb->prev = root->tail; |
root->tail = vb; |
} |
root->count += 1; |
} |
struct snmp_varbind* |
snmp_varbind_tail_remove( struct snmp_varbind_root *root) |
{ |
struct snmp_varbind* vb; |
if (root->count > 0) |
{ |
/* remove tail varbind */ |
vb = root->tail; |
root->tail = vb->prev; |
vb->prev->next = NULL; |
root->count -= 1; |
} |
else |
{ |
/* nothing to remove */ |
vb = NULL; |
} |
return vb; |
} |
#endif /* LWIP_SNMP */ |