/*
* This work is part of the White Rabbit project
*
* Copyright (C) 2016 GSI (www.gsi.de), CERN (www.cern.ch)
* Author: Alessandro Rubini <a.rubini@gsi.de>
* Author: Adam Wujek <adam.wujek@cern.ch>
*
* Released according to the GNU GPL, version 2 or any later version.
*/
#include <string.h>
#include <wrpc.h>
#include <minic.h>
#include <limits.h>
#include "endpoint.h"
#include "ipv4.h"
#include "ptpd_netif.h"
#include "pps_gen.h"
#include "hw/memlayout.h"
#include "hw/etherbone-config.h"
#include "revision.h"
#ifndef htons
#define htons(x) x
#endif
#define ASN_APPLICATION ((u_char)0x40)
#define ASN_INTEGER ((u_char)0x02)
#define ASN_OCTET_STR ((u_char)0x04)
#define ASN_OBJECT_ID ((u_char)0x06)
#define ASN_IPADDRESS (ASN_APPLICATION | 0)
#define ASN_COUNTER (ASN_APPLICATION | 1)
#define ASN_GAUGE (ASN_APPLICATION | 2)
#define ASN_UNSIGNED (ASN_APPLICATION | 2) /* RFC 1902 - same as GAUGE */
#define ASN_TIMETICKS (ASN_APPLICATION | 3)
#define ASN_COUNTER64 (ASN_APPLICATION | 6)
/*
* (error codes from net-snmp's snmp.h)
* Error codes (the value of the field error-status in PDUs)
*/
#define SNMP_ERR_NOERROR (0)
#define SNMP_ERR_TOOBIG (1)
#define SNMP_ERR_NOSUCHNAME (2)
#define SNMP_ERR_BADVALUE (3)
#define SNMP_ERR_READONLY (4)
#define SNMP_ERR_GENERR (5)
#define SNMP_GET 0xA0
#define SNMP_GET_NEXT 0xA1
#define SNMP_GET_RESPONSE 0xA2
#define SNMP_SET 0xA3
#define SNMP_V1 0
#define SNMP_V2c 1
#define SNMP_V_MAX 1 /* Maximum supported version */
#ifdef CONFIG_SNMP_SET
#define SNMP_SET_ENABLED 1
#define SNMP_SET_FUNCTION(X) .set = (X)
#else
#define SNMP_SET_ENABLED 0
#define SNMP_SET_FUNCTION(X) .set = NULL
#endif
struct snmp_oid {
uint8_t *oid_match;
int (*get)(uint8_t *buf, struct snmp_oid *obj);
/* *set is needed only when support for SNMP SET is enabled */
int (*set)(uint8_t *buf, struct snmp_oid *obj);
void *p;
uint8_t oid_len;
uint8_t asn;
uint8_t offset; /* increase it if it is not enough */
uint8_t data_size;
};
extern struct pp_instance ppi_static;
static struct wr_servo_state *wr_s_state;
#define SNMP_SYSTEM_NAME_LEN 32
char snmp_system_name[SNMP_SYSTEM_NAME_LEN] = CONFIG_SNMP_SYSTEM_NAME;
/* store SNMP version, not fully used yet */
uint8_t snmp_version;
static uint8_t __snmp_queue[256];
static struct wrpc_socket __static_snmp_socket = {
.queue.buff = __snmp_queue,
.queue.size = sizeof(__snmp_queue),
};
static struct wrpc_socket *snmp_socket;
static void snmp_init(void)
{
/* Use UDP engine activated by function arguments */
snmp_socket = ptpd_netif_create_socket(&__static_snmp_socket, NULL,
PTPD_SOCK_UDP, 161 /* snmp */);
/* TODO: check if pointer(s) is initialized already */
wr_s_state =
&((struct wr_data *)ppi_static.ext_data)->servo_state;
}
/* These get the actual information, returning the length */
static int get_tics(uint8_t *buf, struct snmp_oid *obj)
{
uint32_t tics = htonl(timer_get_tics() / 10); /* hundredths... bah! */
memcpy(buf + 2, &tics, sizeof(tics));
buf[1] = sizeof(tics);
buf[0] = ASN_TIMETICKS;
return 2 + sizeof(tics);
}
static int get_date(uint8_t *buf, struct snmp_oid *obj)
{
uint64_t secs;
char *datestr;
shw_pps_gen_get_time(&secs, NULL);
datestr = format_time(secs, TIME_FORMAT_SNMP);
memcpy((void *)(buf + 2), datestr, 12);
buf[1] = 8; /* size is hardwired. See mib document or prev. commit */
buf[0] = ASN_OCTET_STR;
return 2 + buf[1];
}
#define MAX_OCTET_STR_LEN 32
static int get_value(uint8_t *buf, uint8_t asn, void *p)
{
uint32_t tmp;
uint8_t *oid_data = buf + 2;
uint8_t *len;
buf[0] = asn;
len = &buf[1];
switch(asn){
case ASN_COUNTER:
case ASN_INTEGER:
tmp = htonl(*(uint32_t*)p);
memcpy(oid_data, &tmp, sizeof(tmp));
*len = sizeof(tmp);
snmp_verbose("%s: 0x%x\n", __func__, *(uint32_t*)p);
break;
case ASN_OCTET_STR:
*len = strnlen((char *)p, MAX_OCTET_STR_LEN - 1);
memcpy(oid_data, p, *len + 1);
snmp_verbose("%s: %s len %d\n", __func__, (char*)p, *len);
break;
default:
break;
}
return 2 + buf[1];
}
static int get_pp(uint8_t *buf, struct snmp_oid *obj)
{
/* calculate pointer, treat obj-> as void ** */
return get_value(buf, obj->asn, *(void **)obj->p + obj->offset);
}
static int get_p(uint8_t *buf, struct snmp_oid *obj)
{
/* calculate pointer, treat obj-> as void * */
return get_value(buf, obj->asn, obj->p + obj->offset);
}
static int get_i32sat(uint8_t *buf, uint8_t asn, void *p) {
int64_t tmp_int64;
int32_t tmp_int32;
/* if we want to modify an object we need to do that on a copy,
* otherwise pointers to the values will be overwritten */
tmp_int64 = *(int64_t *)p;
/* gcc doesn't support printing 64bit values */
snmp_verbose("%s: 64bit value 0x%08x|%08x\n", __func__,
(int32_t)((tmp_int64) >> 32), (uint32_t)tmp_int64);
/* saturate int32 */
if (tmp_int64 >= INT_MAX)
tmp_int64 = INT_MAX;
else if (tmp_int64 <= INT_MIN)
tmp_int64 = INT_MIN;
/* get_value will print saturated value anyway */
tmp_int32 = (int32_t) tmp_int64;
return get_value(buf, asn, &tmp_int32);
}
static int get_i32sat_pp(uint8_t *buf, struct snmp_oid *obj) {
/* calculate pointer, treat obj-> as void ** */
return get_i32sat(buf, obj->asn,
*(void **)obj->p + obj->offset);
}
static int set_value(uint8_t *set_buff, struct snmp_oid *obj, void *p)
{
uint8_t asn_incoming = set_buff[0];
uint8_t asn_expected = obj->asn;
uint8_t len = set_buff[1];
uint8_t *oid_data = set_buff + 2;
uint32_t tmp_u32;
if (asn_incoming != asn_expected) { /* wrong asn */
snmp_verbose("%s: wrong asn 0x%02x, expected 0x%02x\n",
__func__, asn_incoming, asn_expected);
return -1;
}
switch(asn_incoming){
case ASN_INTEGER:
if (len > sizeof(uint32_t))
return -1;
tmp_u32 = 0;
memcpy(&tmp_u32, oid_data, len);
tmp_u32 = ntohl(tmp_u32);
/* move data when shorter than 4 bytes */
tmp_u32 = tmp_u32 >> ((4 - len) * 8);
*(uint32_t *)p = tmp_u32;
snmp_verbose("%s: 0x%08x 0x%08x len %d\n", __func__,
*(uint32_t*)p, tmp_u32, len);
break;
case ASN_OCTET_STR:
/* Check the string size */
if (len > obj->data_size)
return -1;
memcpy(p, oid_data, len);
*(char*)(p + len) = '\0';
snmp_verbose("%s: %s len %d\n", __func__, (char*)p, len);
break;
default:
break;
}
return len + 2;
}
static int set_pp(uint8_t *buf, struct snmp_oid *obj)
{
/* calculate pointer, treat obj-> as void ** */
return set_value(buf, obj, *(void **)obj->p + obj->offset);
}
static int set_p(uint8_t *buf, struct snmp_oid *obj)
{
/* calculate pointer, treat obj-> as void * */
return set_value(buf, obj, obj->p + obj->offset);
}
static uint8_t oid_name[] = {0x2B,0x06,0x01,0x02,0x01,0x01,0x05,0x00};
static uint8_t oid_tics[] = {0x2B,0x06,0x01,0x02,0x01,0x19,0x01,0x01,0x00};
static uint8_t oid_date[] = {0x2B,0x06,0x01,0x02,0x01,0x19,0x01,0x02,0x00};
static uint8_t oid_wrsPtpMode[] = {0x2B,6,1,4,1,96,100,7,5,1, 5,1};
static uint8_t oid_wrsPtpServoState[] = {0x2B,6,1,4,1,96,100,7,5,1, 6,1};
static uint8_t oid_wrsPtpServoStateN[] = {0x2B,6,1,4,1,96,100,7,5,1, 7,1};
static uint8_t oid_wrsPtpClockOffsetPsHR[] = {0x2B,6,1,4,1,96,100,7,5,1,11,1};
static uint8_t oid_wrsPtpSkew[] = {0x2B,6,1,4,1,96,100,7,5,1,12,1};
static uint8_t oid_wrsPtpServoUpdates[] = {0x2B,6,1,4,1,96,100,7,5,1,15,1};
static uint8_t oid_wrsPtpDeltaTxM[] = {0x2B,6,1,4,1,96,100,7,5,1,16,1};
static uint8_t oid_wrsPtpDeltaRxM[] = {0x2B,6,1,4,1,96,100,7,5,1,17,1};
static uint8_t oid_wrsPtpDeltaTxS[] = {0x2B,6,1,4,1,96,100,7,5,1,18,1};
static uint8_t oid_wrsPtpDeltaRxS[] = {0x2B,6,1,4,1,96,100,7,5,1,19,1};
static uint8_t oid_wrpcPtpRTTHR[] = {0x2B,6,1,4,1,96,101,1,1,0}; /* wrsPtpRTT is 64bit, use here saturated version */
static uint8_t oid_wrpcPtpDeltaMs[] = {0x2B,6,1,4,1,96,101,1,2,0};
static uint8_t oid_wrpcPtpCurSetpoint[] = {0x2B,6,1,4,1,96,101,1,3,0};
static uint8_t oid_wrpcNicTX[] = {0x2B,6,1,4,1,96,101,2,1,0};
static uint8_t oid_wrpcNicRX[] = {0x2B,6,1,4,1,96,101,2,2,0};
static uint8_t oid_wrpcVersionSwVersion[] = {0x2B,6,1,4,1,96,101,3,1,0};
#define OID_FIELD_STRUCT(_oid, _getf, _setf, _asn, _type, _pointer, _field) { \
.oid_match = _oid, \
.oid_len = sizeof(_oid), \
.get = _getf, \
SNMP_SET_FUNCTION(_setf), \
.asn = _asn, \
.p = _pointer, \
.offset = offsetof(_type, _field), \
.data_size = sizeof(((_type *)0)->_field) \
}
#define OID_FIELD(_oid, _fname, _asn) { \
.oid_match = _oid, \
.oid_len = sizeof(_oid), \
.get = _fname, \
.asn = _asn, \
}
#define OID_FIELD_VAR(_oid, _getf, _setf, _asn, _pointer) { \
.oid_match = _oid, \
.oid_len = sizeof(_oid), \
.get = _getf, \
SNMP_SET_FUNCTION(_setf), \
.asn = _asn, \
.p = _pointer, \
.offset = 0, \
.data_size = sizeof(*_pointer) \
}
#define NO_SET NULL
/* NOTE: to have SNMP_GET_NEXT working properly this array has to be sorted by
OIDs */
static struct snmp_oid oid_array[] = {
OID_FIELD_VAR( oid_name, get_p, set_p, ASN_OCTET_STR, &snmp_system_name),
OID_FIELD(oid_tics, get_tics, 0),
OID_FIELD(oid_date, get_date, 0),
OID_FIELD_VAR( oid_wrsPtpMode, get_p, set_p, ASN_INTEGER, &ptp_mode),
OID_FIELD_STRUCT(oid_wrsPtpServoState, get_pp, NO_SET, ASN_OCTET_STR, struct wr_servo_state, &wr_s_state, servo_state_name),
OID_FIELD_STRUCT(oid_wrsPtpServoStateN, get_pp, NO_SET, ASN_INTEGER, struct wr_servo_state, &wr_s_state, state),
OID_FIELD_STRUCT(oid_wrsPtpClockOffsetPsHR, get_i32sat_pp, NO_SET, ASN_INTEGER, struct wr_servo_state, &wr_s_state, offset), /* saturated */
OID_FIELD_STRUCT(oid_wrsPtpSkew, get_i32sat_pp, NO_SET, ASN_INTEGER, struct wr_servo_state, &wr_s_state, skew), /* saturated */
OID_FIELD_STRUCT(oid_wrsPtpServoUpdates, get_pp, NO_SET, ASN_COUNTER, struct wr_servo_state, &wr_s_state, update_count),
OID_FIELD_STRUCT(oid_wrsPtpDeltaTxM, get_pp, set_pp, ASN_INTEGER, struct wr_servo_state, &wr_s_state, delta_tx_m),
OID_FIELD_STRUCT(oid_wrsPtpDeltaRxM, get_pp, set_pp, ASN_INTEGER, struct wr_servo_state, &wr_s_state, delta_rx_m),
OID_FIELD_STRUCT(oid_wrsPtpDeltaTxS, get_pp, set_pp, ASN_INTEGER, struct wr_servo_state, &wr_s_state, delta_tx_s),
OID_FIELD_STRUCT(oid_wrsPtpDeltaRxS, get_pp, set_pp, ASN_INTEGER, struct wr_servo_state, &wr_s_state, delta_rx_s),
OID_FIELD_STRUCT(oid_wrpcPtpRTTHR, get_i32sat_pp, NO_SET, ASN_INTEGER, struct wr_servo_state, &wr_s_state, picos_mu), /* saturated */
OID_FIELD_STRUCT(oid_wrpcPtpDeltaMs, get_i32sat_pp, NO_SET, ASN_INTEGER, struct wr_servo_state, &wr_s_state, delta_ms), /* raw value used to calculate wrsPtpLinkLength, original calculations uses float */
OID_FIELD_STRUCT(oid_wrpcPtpCurSetpoint, get_pp, NO_SET, ASN_INTEGER, struct wr_servo_state, &wr_s_state, cur_setpoint),
OID_FIELD_STRUCT(oid_wrpcNicTX, get_p, NO_SET, ASN_COUNTER, struct wr_minic, &minic, tx_count),
OID_FIELD_STRUCT(oid_wrpcNicRX, get_p, NO_SET, ASN_COUNTER, struct wr_minic, &minic, rx_count),
OID_FIELD_VAR( oid_wrpcVersionSwVersion, get_pp, NO_SET, ASN_OCTET_STR, &build_revision),
{ 0, }
};
/*
* Perverse... snmpwalk does getnext anyways.
*
* We support the following ones:
* RFC1213-MIB::sysName.0 (string) .1.3.6.1.2.1.1.5.0
* HOST-RESOURCES-MIB::hrSystemUptime.0 (ticks) .1.3.6.1.2.1.25.1.1.0
* HOST-RESOURCES-MIB::hrSystemDate.0 (string) .1.3.6.1.2.1.25.1.2.0
*
* The request for sysname is like this (-c public):
* 30 29 sequence of 0x29
* 02 01 00 int: snmp version 1 (0x00)
* 04 06 70 75 62 6C 69 63 string of 6: "public"
* A0 1C get request of 0x1c
* 02 04 27 05 36 A9 int of 4: request ID
* 02 01 00 int of 1: error
* 02 01 00 int of 1: error index
* 30 0E sequence of 0x0e
* 30 0C sequence of 0x0c
* 06 08 2B 06 01 02 01 01 05 00 oid of 8: .1.3.6.1.2.1.1.5.0
* 05 00 null
*
*
* Response for sysname:
* 30 30
* 02 01 00
* 04 06 70 75 62 6C 69 63 "public"
* A2 23
* 02 04 27 05 36 A9 seqID
* 02 01 00
* 02 01 00
* 30 15
* 30 13
* 06 08 2B 06 01 02 01 01 05 00
* 04 07 6C 61 70 74 6F 70 6F "laptopo"
*
*/
/*
* The following array defines the frame format, sizes are ignored on read
* but must be filled on write, so mark them specially
*/
#define BYTE_SIZE 0xff
#define BYTE_IGNORE 0xfe
#define BYTE_PDU 0xfd
#define BYTE_ERROR 0xfc
#define BYTE_ERROR_INDEX 0xfb
#define BYTE_VERSION 0xfa
/* indexes of bytes in snmp packet */
#define BYTE_PACKET_SIZE_i 1
#define BYTE_COMMUNITY_LEN_i 6
/* indexes below are without the length of the community string */
#define BYTE_PDU_i 7
#define BYTE_ERROR_i 17
#define BYTE_ERROR_INDEX_i 20
static uint8_t match_array[] = {
0x30, BYTE_SIZE,
0x02, 0x01, BYTE_VERSION, /* ASN_INTEGER, size 1 byte, version */
0x04, 0x06, /* ASN_OCTET_STR, strlen("public") */
0x70, 0x75, 0x62, 0x6C, 0x69, 0x63, /* "public" */
BYTE_PDU, BYTE_SIZE, /* SNMP packet type, size of following data */
0x02, 0x04, BYTE_IGNORE, BYTE_IGNORE, BYTE_IGNORE, BYTE_IGNORE, /*
* ASN_INTEGER, size 4 bytes, Request/Message ID */
0x02, 0x01, BYTE_ERROR, /* ASN_INTEGER, size 1 byte, error type */
0x02, 0x01, BYTE_ERROR_INDEX, /* ASN_INTEGER, size 1 byte,
* error index */
0x30, BYTE_SIZE,
0x30, BYTE_SIZE,
0x06, BYTE_IGNORE, /* ASN_OBJECT_ID, OID length */
/* oid follows */
};
static void print_oid_verbose(uint8_t *oid, int len) {
/*uint8_t * oid_end = oid + len;*/
int i;
snmp_verbose(".1.3");
for (i = 1; i < len; i++)
snmp_verbose(".%d", *(oid + i));
}
/* Limit community length. Standard says nothing about maximum length, but we
* want to limit it to save memory */
#define MAX_COMMUNITY_LEN 32
/* prepare packet to return error, leave the rest of packet as it was */
static uint8_t snmp_prepare_error(uint8_t *buf, uint8_t error)
{
uint8_t ret_size;
uint8_t community_len;
community_len = buf[BYTE_COMMUNITY_LEN_i];
/* If community_len is too long, it will return malformed
* packet, but at least something useful for debugging */
community_len = min(community_len, MAX_COMMUNITY_LEN);
buf[BYTE_PDU_i + community_len] = SNMP_GET_RESPONSE;
buf[BYTE_ERROR_i + community_len] = error;
buf[BYTE_ERROR_INDEX_i + community_len] = 1;
ret_size = buf[BYTE_PACKET_SIZE_i] + 2;
snmp_verbose("%s: error returning %i bytes\n", __func__,
ret_size);
return ret_size;
}
/* And, now, work out your generic frame responder... */
static int snmp_respond(uint8_t *buf)
{
struct snmp_oid *oid = NULL;
uint8_t *newbuf = NULL;
uint8_t *new_oid;;
int i;
int8_t len;
uint8_t snmp_mode_get = 0;
uint8_t snmp_mode_get_next = 0;
uint8_t snmp_mode_set = 0;
uint8_t incoming_oid_len;
int8_t cmp_result;
/* Hack to avoid compiler warnings "function defined but not used" for
* set_p and set_pp when SNMP compiled without SET support.
* These functions will never be called here. */
if (0) {
set_p(newbuf, oid);
set_pp(newbuf, oid);
}
for (i = 0; i < sizeof(match_array); i++) {
switch (match_array[i]) {
case BYTE_SIZE:
case BYTE_IGNORE:
case BYTE_ERROR:
case BYTE_ERROR_INDEX:
continue;
case BYTE_VERSION:
snmp_version = buf[i];
if (snmp_version > SNMP_V_MAX)
return snmp_prepare_error(buf,
SNMP_ERR_GENERR);
continue;
case BYTE_PDU:
snmp_mode_get = (SNMP_GET == buf[i]);
snmp_mode_get_next = (SNMP_GET_NEXT == buf[i]);
snmp_mode_set = SNMP_SET_ENABLED &&
(SNMP_SET == buf[i]);
if (!(snmp_mode_get
|| snmp_mode_get_next
|| snmp_mode_set))
return snmp_prepare_error(buf,
SNMP_ERR_GENERR);
break;
default:
if (buf[i] != match_array[i])
return snmp_prepare_error(buf,
SNMP_ERR_GENERR);
}
}
snmp_verbose("%s: header match ok\n", __func__);
newbuf = buf + i;
new_oid = buf + i;
/* save size of incoming oid */
incoming_oid_len = buf[i - 1];
for (oid = oid_array; oid->oid_len; oid++) {
if (snmp_mode_get &&
oid->oid_len != incoming_oid_len) {
/* for SNMP_GET, we need equal lengths */
continue;
}
cmp_result = memcmp(oid->oid_match, new_oid,
min(oid->oid_len, incoming_oid_len));
if (snmp_mode_get || snmp_mode_set) {
/* we need exact match for SNMP_GET */
if (cmp_result == 0) {
snmp_verbose("%s: exact match for %s\n",
__func__,
snmp_mode_set ? "SET" : "GET");
break;
}
} else if (snmp_mode_get_next) {
if (cmp_result > 0) { /* current OID is after the one
* that is requested, so use it
*/
snmp_verbose("%s: take next match for GET_NEXT"
"\n", __func__);
break;
}
if (cmp_result == 0) { /* exact match */
if (oid->oid_len <= incoming_oid_len) {
/* when incoming OID is equal or longer
* than OID beeing compared, go to next
* OID and break */
oid++;
}
snmp_verbose("%s: exact match for GET_NEXT\n",
__func__);
break;
}
}
}
if (!oid->oid_len) {
snmp_verbose("%s: OID not found! ", __func__);
print_oid_verbose(new_oid, incoming_oid_len);
snmp_verbose(" \n");
/* also for last GET_NEXT element */
return snmp_prepare_error(buf, SNMP_ERR_NOSUCHNAME);
}
if (snmp_mode_get_next) {
/* copy new OID */
memcpy(new_oid, oid->oid_match, oid->oid_len);
/* update OID len, since it might be different */
*(new_oid - 1) = oid->oid_len;
}
snmp_verbose("%s: oid found: ", __func__);
print_oid_verbose(oid->oid_match, oid->oid_len);
snmp_verbose(" calling %p\n", oid->get);
/* Phew.... we matched the OID, so let's call the filler */
newbuf += oid->oid_len;
if (SNMP_SET_ENABLED && snmp_mode_set) {
uint8_t community_len;
if (!oid->set) {
/* Oid found but there is no set function.
* It is read-only */
return snmp_prepare_error(buf,
SNMP_ERR_READONLY);
}
len = oid->set(newbuf, oid);
if (len < 0)
return snmp_prepare_error(buf,
SNMP_ERR_BADVALUE);
/* After set, perform get */
community_len = buf[BYTE_COMMUNITY_LEN_i];
/* If community_len is too long, it will return malformed
* packet, but at least something useful for debugging */
community_len = min(community_len, MAX_COMMUNITY_LEN);
buf[BYTE_PDU_i + community_len] = SNMP_GET;
/* recursive call of snmp_respond */
return snmp_respond(buf);
} else {
len = oid->get(newbuf, oid);
newbuf += len;
}
/* now fix all size fields and change PDU */
for (i = 0; i < sizeof(match_array); i++) {
int remain = newbuf - buf - i - 1;
if (match_array[i] == BYTE_PDU)
buf[i] = SNMP_GET_RESPONSE;
if (match_array[i] != BYTE_SIZE)
continue;
snmp_verbose("%s: offset %i 0x%02x is len %i\n", i, i,
__func__, remain);
buf[i] = remain;
}
snmp_verbose("%s: returning %i bytes\n", __func__, newbuf - buf);
return newbuf - buf;
}
/* receive snmp through the UDP mechanism */
static int snmp_poll(void)
{
struct wr_sockaddr addr;
uint8_t buf[200];
int len;
/* no need to wait for IP address: we won't get queries */
len = ptpd_netif_recvfrom(snmp_socket, &addr,
buf, sizeof(buf), NULL);
if (len <= UDP_END + sizeof(match_array))
return 0;
len = snmp_respond(buf + UDP_END);
if (len < 0)
return 0;
len += UDP_END;
fill_udp(buf, len, NULL);
ptpd_netif_sendto(snmp_socket, &addr, buf, len, 0);
return 1;
}
DEFINE_WRC_TASK(snmp) = {
.name = "snmp",
.enable = &link_status,
.init = snmp_init,
.job = snmp_poll,
};