748 lines
23 KiB
C
748 lines
23 KiB
C
/**
|
|
* @file
|
|
* SNTP client module
|
|
*
|
|
*/
|
|
|
|
/*
|
|
* 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.
|
|
*
|
|
* This file is part of the lwIP TCP/IP stack.
|
|
*
|
|
* Author: Simon Goldschmidt (lwIP raw API part)
|
|
*
|
|
* Modified by Jesus Alonso (doragasu) to allow setting servers dynamically.
|
|
*/
|
|
|
|
#include "lwip/opt.h"
|
|
|
|
#include "sntp.h"
|
|
|
|
#include "lwip/timeouts.h"
|
|
#include "lwip/udp.h"
|
|
#include "lwip/dns.h"
|
|
#include "lwip/ip_addr.h"
|
|
#include "lwip/pbuf.h"
|
|
|
|
#include <string.h>
|
|
#include <time.h>
|
|
|
|
#if LWIP_UDP
|
|
|
|
/** This is simple "SNTP" client for socket or raw API.
|
|
* It is a minimal implementation of SNTPv4 as specified in RFC 4330.
|
|
*
|
|
* For a list of some public NTP servers, see this link :
|
|
* http://support.ntp.org/bin/view/Servers/NTPPoolServers
|
|
*
|
|
* @todo:
|
|
* - set/change servers at runtime
|
|
* - complete SNTP_CHECK_RESPONSE checks 3 and 4
|
|
* - support broadcast/multicast mode?
|
|
*/
|
|
|
|
/** Decide whether to build SNTP for socket or raw API
|
|
* The socket API SNTP client is a very minimal implementation that does not
|
|
* fully confor to the SNTPv4 RFC, especially regarding server load and error
|
|
* procesing. */
|
|
#ifndef SNTP_SOCKET
|
|
#define SNTP_SOCKET 0
|
|
#endif
|
|
|
|
#if SNTP_SOCKET
|
|
#include "lwip/sockets.h"
|
|
#endif
|
|
|
|
/**
|
|
* SNTP_DEBUG: Enable debugging for SNTP.
|
|
*/
|
|
#ifndef SNTP_DEBUG
|
|
#define SNTP_DEBUG LWIP_DBG_OFF
|
|
#endif
|
|
|
|
/** SNTP server port */
|
|
#ifndef SNTP_PORT
|
|
#define SNTP_PORT 123
|
|
#endif
|
|
|
|
/** Set this to 1 to allow SNTP_SERVER_ADDRESS to be a DNS name */
|
|
#ifndef SNTP_SERVER_DNS
|
|
#define SNTP_SERVER_DNS 0
|
|
#endif
|
|
|
|
/** Set to the number of servers supported (at least 1) */
|
|
#ifndef SNTP_NUM_SERVERS_SUPPORTED
|
|
#define SNTP_NUM_SERVERS_SUPPORTED 1
|
|
#endif
|
|
|
|
/** SNTP server address:
|
|
* - as IPv4 address in "u32_t" format
|
|
* - as a DNS name if SNTP_SERVER_DNS is set to 1
|
|
* May contain multiple server names (e.g. "pool.ntp.org","second.time.server")
|
|
*/
|
|
#ifndef SNTP_SERVER_ADDRESS
|
|
#if SNTP_SERVER_DNS
|
|
#define SNTP_SERVER_ADDRESS "pool.ntp.org"
|
|
#else
|
|
#define SNTP_SERVER_ADDRESS "213.161.194.93" /* pool.ntp.org */
|
|
#endif
|
|
#endif
|
|
|
|
/** Sanity check:
|
|
* Define this to
|
|
* - 0 to turn off sanity checks (default; smaller code)
|
|
* - >= 1 to check address and port of the response packet to ensure the
|
|
* response comes from the server we sent the request to.
|
|
* - >= 2 to check returned Originate Timestamp against Transmit Timestamp
|
|
* sent to the server (to ensure response to older request).
|
|
* - >= 3 @todo: discard reply if any of the LI, Stratum, or Transmit Timestamp
|
|
* fields is 0 or the Mode field is not 4 (unicast) or 5 (broadcast).
|
|
* - >= 4 @todo: to check that the Root Delay and Root Dispersion fields are each
|
|
* greater than or equal to 0 and less than infinity, where infinity is
|
|
* currently a cozy number like one second. This check avoids using a
|
|
* server whose synchronization source has expired for a very long time.
|
|
*/
|
|
#ifndef SNTP_CHECK_RESPONSE
|
|
#define SNTP_CHECK_RESPONSE 0
|
|
#endif
|
|
|
|
/** According to the RFC, this shall be a random delay
|
|
* between 1 and 5 minutes (in milliseconds) to prevent load peaks.
|
|
* This can be defined to a random generation function,
|
|
* which must return the delay in milliseconds as u32_t.
|
|
* Turned off by default.
|
|
*/
|
|
#ifndef SNTP_STARTUP_DELAY
|
|
#define SNTP_STARTUP_DELAY 0
|
|
#endif
|
|
|
|
/** SNTP receive timeout - in seconds
|
|
* Also used as retry timeout - this shouldn't be too low.
|
|
* Default is 3 seconds.
|
|
*/
|
|
#ifndef SNTP_RECV_TIMEOUT
|
|
#define SNTP_RECV_TIMEOUT 3
|
|
#endif
|
|
|
|
/** SNTP update delay - in milliseconds
|
|
* Default is 1 hour.
|
|
*/
|
|
#ifndef SNTP_UPDATE_DELAY
|
|
#define SNTP_UPDATE_DELAY 3600000
|
|
#endif
|
|
#if (SNTP_UPDATE_DELAY < 15000) && !SNTP_SUPPRESS_DELAY_CHECK
|
|
#error "SNTPv4 RFC 4330 enforces a minimum update time of 15 seconds!"
|
|
#endif
|
|
|
|
/** SNTP macro to change system time and/or the update the RTC clock */
|
|
#ifndef SNTP_SET_SYSTEM_TIME
|
|
#define SNTP_SET_SYSTEM_TIME(sec) ((void)sec)
|
|
#endif
|
|
|
|
/** SNTP macro to change system time including microseconds */
|
|
#ifdef SNTP_SET_SYSTEM_TIME_US
|
|
#define SNTP_CALC_TIME_US 1
|
|
#define SNTP_RECEIVE_TIME_SIZE 2
|
|
#else
|
|
#define SNTP_SET_SYSTEM_TIME_US(sec, us)
|
|
#define SNTP_CALC_TIME_US 0
|
|
#define SNTP_RECEIVE_TIME_SIZE 1
|
|
#endif
|
|
|
|
/** SNTP macro to get system time, used with SNTP_CHECK_RESPONSE >= 2
|
|
* to send in request and compare in response.
|
|
*/
|
|
#ifndef SNTP_GET_SYSTEM_TIME
|
|
#define SNTP_GET_SYSTEM_TIME(sec, us) do { (sec) = 0; (us) = 0; } while(0)
|
|
#endif
|
|
|
|
/** Default retry timeout (in milliseconds) if the response
|
|
* received is invalid.
|
|
* This is doubled with each retry until SNTP_RETRY_TIMEOUT_MAX is reached.
|
|
*/
|
|
#ifndef SNTP_RETRY_TIMEOUT
|
|
#define SNTP_RETRY_TIMEOUT SNTP_RECV_TIMEOUT
|
|
#endif
|
|
|
|
/** Maximum retry timeout (in milliseconds). */
|
|
#ifndef SNTP_RETRY_TIMEOUT_MAX
|
|
#define SNTP_RETRY_TIMEOUT_MAX (SNTP_RETRY_TIMEOUT * 10)
|
|
#endif
|
|
|
|
/** Increase retry timeout with every retry sent
|
|
* Default is on to conform to RFC.
|
|
*/
|
|
#ifndef SNTP_RETRY_TIMEOUT_EXP
|
|
#define SNTP_RETRY_TIMEOUT_EXP 1
|
|
#endif
|
|
|
|
/* the various debug levels for this file */
|
|
#define SNTP_DEBUG_TRACE (SNTP_DEBUG | LWIP_DBG_TRACE)
|
|
#define SNTP_DEBUG_STATE (SNTP_DEBUG | LWIP_DBG_STATE)
|
|
#define SNTP_DEBUG_WARN (SNTP_DEBUG | LWIP_DBG_LEVEL_WARNING)
|
|
#define SNTP_DEBUG_WARN_STATE (SNTP_DEBUG | LWIP_DBG_LEVEL_WARNING | LWIP_DBG_STATE)
|
|
#define SNTP_DEBUG_SERIOUS (SNTP_DEBUG | LWIP_DBG_LEVEL_SERIOUS)
|
|
|
|
#define SNTP_ERR_KOD 1
|
|
|
|
/* SNTP protocol defines */
|
|
#define SNTP_MSG_LEN 48
|
|
|
|
#define SNTP_OFFSET_LI_VN_MODE 0
|
|
#define SNTP_LI_MASK 0xC0
|
|
#define SNTP_LI_NO_WARNING 0x00
|
|
#define SNTP_LI_LAST_MINUTE_61_SEC 0x01
|
|
#define SNTP_LI_LAST_MINUTE_59_SEC 0x02
|
|
#define SNTP_LI_ALARM_CONDITION 0x03 /* (clock not synchronized) */
|
|
|
|
#define SNTP_VERSION_MASK 0x38
|
|
#define SNTP_VERSION (4/* NTP Version 4*/<<3)
|
|
|
|
#define SNTP_MODE_MASK 0x07
|
|
#define SNTP_MODE_CLIENT 0x03
|
|
#define SNTP_MODE_SERVER 0x04
|
|
#define SNTP_MODE_BROADCAST 0x05
|
|
|
|
#define SNTP_OFFSET_STRATUM 1
|
|
#define SNTP_STRATUM_KOD 0x00
|
|
|
|
#define SNTP_OFFSET_ORIGINATE_TIME 24
|
|
#define SNTP_OFFSET_RECEIVE_TIME 32
|
|
#define SNTP_OFFSET_TRANSMIT_TIME 40
|
|
|
|
/* number of seconds between 1900 and 1970 */
|
|
#define DIFF_SEC_1900_1970 (2208988800UL)
|
|
|
|
/**
|
|
* SNTP packet format (without optional fields)
|
|
* Timestamps are coded as 64 bits:
|
|
* - 32 bits seconds since Jan 01, 1970, 00:00
|
|
* - 32 bits seconds fraction (0-padded)
|
|
* For future use, if the MSB in the seconds part is set, seconds are based
|
|
* on Feb 07, 2036, 06:28:16.
|
|
*/
|
|
#ifdef PACK_STRUCT_USE_INCLUDES
|
|
# include "arch/bpstruct.h"
|
|
#endif
|
|
PACK_STRUCT_BEGIN
|
|
struct sntp_msg {
|
|
PACK_STRUCT_FIELD(u8_t li_vn_mode);
|
|
PACK_STRUCT_FIELD(u8_t stratum);
|
|
PACK_STRUCT_FIELD(u8_t poll);
|
|
PACK_STRUCT_FIELD(u8_t precision);
|
|
PACK_STRUCT_FIELD(u32_t root_delay);
|
|
PACK_STRUCT_FIELD(u32_t root_dispersion);
|
|
PACK_STRUCT_FIELD(u32_t reference_identifier);
|
|
PACK_STRUCT_FIELD(u32_t reference_timestamp[2]);
|
|
PACK_STRUCT_FIELD(u32_t originate_timestamp[2]);
|
|
PACK_STRUCT_FIELD(u32_t receive_timestamp[2]);
|
|
PACK_STRUCT_FIELD(u32_t transmit_timestamp[2]);
|
|
} PACK_STRUCT_STRUCT;
|
|
PACK_STRUCT_END
|
|
#ifdef PACK_STRUCT_USE_INCLUDES
|
|
# include "arch/epstruct.h"
|
|
#endif
|
|
|
|
/* function prototypes */
|
|
static void sntp_request(void *arg);
|
|
|
|
/** The UDP pcb used by the SNTP client */
|
|
static struct udp_pcb* sntp_pcb;
|
|
/** Addresses of servers */
|
|
static char* sntp_server_addresses[SNTP_NUM_SERVERS_SUPPORTED];
|
|
/** The currently used server (initialized to 0) */
|
|
static u8_t sntp_num_servers;
|
|
#if (SNTP_NUM_SERVERS_SUPPORTED > 1)
|
|
static u8_t sntp_current_server;
|
|
#else
|
|
#define sntp_current_server 0
|
|
#endif /* SNTP_NUM_SERVERS_SUPPORTED */
|
|
|
|
static u32_t sntp_update_delay = SNTP_UPDATE_DELAY;
|
|
|
|
#if SNTP_RETRY_TIMEOUT_EXP
|
|
#define SNTP_RESET_RETRY_TIMEOUT() sntp_retry_timeout = SNTP_RETRY_TIMEOUT
|
|
/** Retry time, initialized with SNTP_RETRY_TIMEOUT and doubled with each retry. */
|
|
static u32_t sntp_retry_timeout;
|
|
#else /* SNTP_RETRY_TIMEOUT_EXP */
|
|
#define SNTP_RESET_RETRY_TIMEOUT()
|
|
#define sntp_retry_timeout SNTP_RETRY_TIMEOUT
|
|
#endif /* SNTP_RETRY_TIMEOUT_EXP */
|
|
|
|
#if SNTP_CHECK_RESPONSE >= 1
|
|
/** Saves the last server address to compare with response */
|
|
static ip_addr_t sntp_last_server_address;
|
|
#endif /* SNTP_CHECK_RESPONSE >= 1 */
|
|
|
|
#if SNTP_CHECK_RESPONSE >= 2
|
|
/** Saves the last timestamp sent (which is sent back by the server)
|
|
* to compare against in response */
|
|
static u32_t sntp_last_timestamp_sent[2];
|
|
#endif /* SNTP_CHECK_RESPONSE >= 2 */
|
|
|
|
/**
|
|
* SNTP processing of received timestamp
|
|
*/
|
|
static void
|
|
sntp_process(u32_t *receive_timestamp)
|
|
{
|
|
/* convert SNTP time (1900-based) to unix GMT time (1970-based)
|
|
* @todo: if MSB is 1, SNTP time is 2036-based!
|
|
*/
|
|
time_t t = (ntohl(receive_timestamp[0]) - DIFF_SEC_1900_1970);
|
|
|
|
#if SNTP_CALC_TIME_US
|
|
u32_t us = ntohl(receive_timestamp[1]) / 4295;
|
|
SNTP_SET_SYSTEM_TIME_US(t, us);
|
|
/* display local time from GMT time */
|
|
LWIP_DEBUGF(SNTP_DEBUG_TRACE, ("sntp_process: %s, %"U32_F" us", ctime(&t), us));
|
|
|
|
#else /* SNTP_CALC_TIME_US */
|
|
|
|
/* change system time and/or the update the RTC clock */
|
|
SNTP_SET_SYSTEM_TIME(t);
|
|
/* display local time from GMT time */
|
|
LWIP_DEBUGF(SNTP_DEBUG_TRACE, ("sntp_process: %s", ctime(&t)));
|
|
#endif /* SNTP_CALC_TIME_US */
|
|
}
|
|
|
|
/**
|
|
* Initialize request struct to be sent to server.
|
|
*/
|
|
static void
|
|
sntp_initialize_request(struct sntp_msg *req)
|
|
{
|
|
memset(req, 0, SNTP_MSG_LEN);
|
|
req->li_vn_mode = SNTP_LI_NO_WARNING | SNTP_VERSION | SNTP_MODE_CLIENT;
|
|
|
|
#if SNTP_CHECK_RESPONSE >= 2
|
|
{
|
|
u32_t sntp_time_sec, sntp_time_us;
|
|
/* fill in transmit timestamp and save it in 'sntp_last_timestamp_sent' */
|
|
SNTP_GET_SYSTEM_TIME(sntp_time_sec, sntp_time_us);
|
|
sntp_last_timestamp_sent[0] = htonl(sntp_time_sec + DIFF_SEC_1900_1970);
|
|
req->transmit_timestamp[0] = sntp_last_timestamp_sent[0];
|
|
/* we send/save us instead of fraction to be faster... */
|
|
sntp_last_timestamp_sent[1] = htonl(sntp_time_us);
|
|
req->transmit_timestamp[1] = sntp_last_timestamp_sent[1];
|
|
}
|
|
#endif /* SNTP_CHECK_RESPONSE >= 2 */
|
|
}
|
|
|
|
#if SNTP_SOCKET
|
|
|
|
/**
|
|
* Send an SNTP request via sockets.
|
|
* This is a very minimal implementation that does not fully conform
|
|
* to the SNTPv4 RFC, especially regarding server load and error procesing.
|
|
*/
|
|
static void
|
|
sntp_request(void *arg)
|
|
{
|
|
int sock;
|
|
struct sockaddr_in local;
|
|
struct sockaddr_in to;
|
|
int tolen;
|
|
int size;
|
|
int timeout;
|
|
struct sntp_msg sntpmsg;
|
|
ip_addr_t sntp_server_address;
|
|
|
|
LWIP_UNUSED_ARG(arg);
|
|
|
|
/* if we got a valid SNTP server address... */
|
|
if (ipaddr_aton(SNTP_SERVER_ADDRESS, &sntp_server_address)) {
|
|
/* create new socket */
|
|
sock = lwip_socket(AF_INET, SOCK_DGRAM, 0);
|
|
if (sock >= 0) {
|
|
/* prepare local address */
|
|
memset(&local, 0, sizeof(local));
|
|
local.sin_family = AF_INET;
|
|
local.sin_port = PP_HTONS(INADDR_ANY);
|
|
local.sin_addr.s_addr = PP_HTONL(INADDR_ANY);
|
|
|
|
/* bind to local address */
|
|
if (lwip_bind(sock, (struct sockaddr *)&local, sizeof(local)) == 0) {
|
|
/* set recv timeout */
|
|
const struct timeval timeout = { SNTP_RECV_TIMEOUT, 0 };
|
|
setsockopt(sock, SOL_SOCKET, SO_RCVTIMEO, &timeout, sizeof(timeout));
|
|
|
|
/* prepare SNTP request */
|
|
sntp_initialize_request(&sntpmsg);
|
|
|
|
/* prepare SNTP server address */
|
|
memset(&to, 0, sizeof(to));
|
|
to.sin_family = AF_INET;
|
|
to.sin_port = PP_HTONS(SNTP_PORT);
|
|
inet_addr_from_ipaddr(&to.sin_addr, &sntp_server_address);
|
|
|
|
/* send SNTP request to server */
|
|
if (lwip_sendto(sock, &sntpmsg, SNTP_MSG_LEN, 0, (struct sockaddr *)&to, sizeof(to)) >= 0) {
|
|
/* receive SNTP server response */
|
|
tolen = sizeof(to);
|
|
size = lwip_recvfrom(sock, &sntpmsg, SNTP_MSG_LEN, 0, (struct sockaddr *)&to, (socklen_t *)&tolen);
|
|
/* if the response size is good */
|
|
if (size == SNTP_MSG_LEN) {
|
|
/* if this is a SNTP response... */
|
|
if (((sntpmsg.li_vn_mode & SNTP_MODE_MASK) == SNTP_MODE_SERVER) ||
|
|
((sntpmsg.li_vn_mode & SNTP_MODE_MASK) == SNTP_MODE_BROADCAST)) {
|
|
/* do time processing */
|
|
sntp_process(sntpmsg.receive_timestamp);
|
|
} else {
|
|
LWIP_DEBUGF( SNTP_DEBUG_WARN, ("sntp_request: not response frame code\n"));
|
|
}
|
|
}
|
|
} else {
|
|
LWIP_DEBUGF( SNTP_DEBUG_WARN, ("sntp_request: not sendto==%i\n", errno));
|
|
}
|
|
}
|
|
/* close the socket */
|
|
closesocket(sock);
|
|
}
|
|
}
|
|
}
|
|
|
|
/**
|
|
* SNTP thread
|
|
*/
|
|
static void
|
|
sntp_thread(void *arg)
|
|
{
|
|
LWIP_UNUSED_ARG(arg);
|
|
while(1) {
|
|
sntp_request(NULL);
|
|
sys_msleep(sntp_update_delay);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Initialize this module when using sockets
|
|
*/
|
|
void
|
|
sntp_init(void)
|
|
{
|
|
sys_thread_new("sntp_thread", sntp_thread, NULL, DEFAULT_THREAD_STACKSIZE, DEFAULT_THREAD_PRIO);
|
|
}
|
|
|
|
#else /* SNTP_SOCKET */
|
|
|
|
/**
|
|
* Retry: send a new request (and increase retry timeout).
|
|
*
|
|
* @param arg is unused (only necessary to conform to sys_timeout)
|
|
*/
|
|
static void
|
|
sntp_retry(void* arg)
|
|
{
|
|
LWIP_UNUSED_ARG(arg);
|
|
|
|
LWIP_DEBUGF(SNTP_DEBUG_STATE, ("sntp_retry: Next request will be sent in %"U32_F" ms\n",
|
|
sntp_retry_timeout));
|
|
|
|
/* set up a timer to send a retry and increase the retry delay */
|
|
sys_timeout(sntp_retry_timeout, sntp_request, NULL);
|
|
|
|
#if SNTP_RETRY_TIMEOUT_EXP
|
|
{
|
|
u32_t new_retry_timeout;
|
|
/* increase the timeout for next retry */
|
|
new_retry_timeout = sntp_retry_timeout << 1;
|
|
/* limit to maximum timeout and prevent overflow */
|
|
if ((new_retry_timeout <= SNTP_RETRY_TIMEOUT_MAX) &&
|
|
(new_retry_timeout > sntp_retry_timeout)) {
|
|
sntp_retry_timeout = new_retry_timeout;
|
|
}
|
|
}
|
|
#endif /* SNTP_RETRY_TIMEOUT_EXP */
|
|
}
|
|
|
|
#if (SNTP_NUM_SERVERS_SUPPORTED > 1)
|
|
/**
|
|
* If Kiss-of-Death is received (or another packet parsing error),
|
|
* try the next server or retry the current server and increase the retry
|
|
* timeout if only one server is available.
|
|
*
|
|
* @param arg is unused (only necessary to conform to sys_timeout)
|
|
*/
|
|
static void
|
|
sntp_try_next_server(void* arg)
|
|
{
|
|
LWIP_UNUSED_ARG(arg);
|
|
|
|
if (sntp_num_servers > 1) {
|
|
/* new server: reset retry timeout */
|
|
SNTP_RESET_RETRY_TIMEOUT();
|
|
sntp_current_server++;
|
|
if (sntp_current_server >= sntp_num_servers) {
|
|
sntp_current_server = 0;
|
|
}
|
|
LWIP_DEBUGF(SNTP_DEBUG_STATE, ("sntp_try_next_server: Sending request to server %"U16_F"\n",
|
|
(u16_t)sntp_current_server));
|
|
/* instantly send a request to the next server */
|
|
sntp_request(NULL);
|
|
} else {
|
|
sntp_retry(NULL);
|
|
}
|
|
}
|
|
#else /* SNTP_NUM_SERVERS_SUPPORTED > 1 */
|
|
/* Always retry on error if only one server is supported */
|
|
#define sntp_try_next_server sntp_retry
|
|
#endif /* SNTP_NUM_SERVERS_SUPPORTED > 1 */
|
|
|
|
/** UDP recv callback for the sntp pcb */
|
|
static void
|
|
sntp_recv(void *arg, struct udp_pcb* pcb, struct pbuf *p, const ip_addr_t *addr, u16_t port)
|
|
{
|
|
u8_t mode;
|
|
u8_t stratum;
|
|
u32_t receive_timestamp[SNTP_RECEIVE_TIME_SIZE];
|
|
err_t err;
|
|
|
|
LWIP_UNUSED_ARG(arg);
|
|
LWIP_UNUSED_ARG(pcb);
|
|
|
|
/* packet received: stop retry timeout */
|
|
sys_untimeout(sntp_try_next_server, NULL);
|
|
sys_untimeout(sntp_request, NULL);
|
|
|
|
err = ERR_ARG;
|
|
#if SNTP_CHECK_RESPONSE >= 1
|
|
/* check server address and port */
|
|
if (ip_addr_cmp(addr, &sntp_last_server_address) &&
|
|
(port == SNTP_PORT))
|
|
#else /* SNTP_CHECK_RESPONSE >= 1 */
|
|
LWIP_UNUSED_ARG(addr);
|
|
LWIP_UNUSED_ARG(port);
|
|
#endif /* SNTP_CHECK_RESPONSE >= 1 */
|
|
{
|
|
/* process the response */
|
|
if (p->tot_len == SNTP_MSG_LEN) {
|
|
pbuf_copy_partial(p, &mode, 1, SNTP_OFFSET_LI_VN_MODE);
|
|
mode &= SNTP_MODE_MASK;
|
|
/* if this is a SNTP response... */
|
|
if ((mode == SNTP_MODE_SERVER) ||
|
|
(mode == SNTP_MODE_BROADCAST)) {
|
|
pbuf_copy_partial(p, &stratum, 1, SNTP_OFFSET_STRATUM);
|
|
if (stratum == SNTP_STRATUM_KOD) {
|
|
/* Kiss-of-death packet. Use another server or increase UPDATE_DELAY. */
|
|
err = SNTP_ERR_KOD;
|
|
LWIP_DEBUGF(SNTP_DEBUG_STATE, ("sntp_recv: Received Kiss-of-Death\n"));
|
|
} else {
|
|
#if SNTP_CHECK_RESPONSE >= 2
|
|
/* check originate_timetamp against sntp_last_timestamp_sent */
|
|
u32_t originate_timestamp[2];
|
|
pbuf_copy_partial(p, &originate_timestamp, 8, SNTP_OFFSET_ORIGINATE_TIME);
|
|
if ((originate_timestamp[0] != sntp_last_timestamp_sent[0]) ||
|
|
(originate_timestamp[1] != sntp_last_timestamp_sent[1]))
|
|
{
|
|
LWIP_DEBUGF(SNTP_DEBUG_WARN, ("sntp_recv: Invalid originate timestamp in response\n"));
|
|
} else
|
|
#endif /* SNTP_CHECK_RESPONSE >= 2 */
|
|
/* @todo: add code for SNTP_CHECK_RESPONSE >= 3 and >= 4 here */
|
|
{
|
|
/* correct answer */
|
|
err = ERR_OK;
|
|
pbuf_copy_partial(p, &receive_timestamp, SNTP_RECEIVE_TIME_SIZE * 4, SNTP_OFFSET_RECEIVE_TIME);
|
|
}
|
|
}
|
|
} else {
|
|
LWIP_DEBUGF(SNTP_DEBUG_WARN, ("sntp_recv: Invalid mode in response: %"U16_F"\n", (u16_t)mode));
|
|
}
|
|
} else {
|
|
LWIP_DEBUGF(SNTP_DEBUG_WARN, ("sntp_recv: Invalid packet length: %"U16_F"\n", p->tot_len));
|
|
}
|
|
}
|
|
pbuf_free(p);
|
|
if (err == ERR_OK) {
|
|
/* Correct response, reset retry timeout */
|
|
SNTP_RESET_RETRY_TIMEOUT();
|
|
|
|
sntp_process(receive_timestamp);
|
|
|
|
/* Set up timeout for next request */
|
|
sys_timeout(sntp_update_delay, sntp_request, NULL);
|
|
LWIP_DEBUGF(SNTP_DEBUG_STATE, ("sntp_recv: Scheduled next time request: %"U32_F" ms\n",
|
|
sntp_update_delay));
|
|
} else if (err == SNTP_ERR_KOD) {
|
|
/* Kiss-of-death packet. Use another server or increase UPDATE_DELAY. */
|
|
sntp_try_next_server(NULL);
|
|
} else {
|
|
/* another error, try the same server again */
|
|
sntp_retry(NULL);
|
|
}
|
|
}
|
|
|
|
/** Actually send an sntp request to a server.
|
|
*
|
|
* @param server_addr resolved IP address of the SNTP server
|
|
*/
|
|
static void
|
|
sntp_send_request(const ip_addr_t *server_addr)
|
|
{
|
|
struct pbuf* p;
|
|
p = pbuf_alloc(PBUF_TRANSPORT, SNTP_MSG_LEN, PBUF_RAM);
|
|
if (p != NULL) {
|
|
struct sntp_msg *sntpmsg = (struct sntp_msg *)p->payload;
|
|
LWIP_DEBUGF(SNTP_DEBUG_STATE, ("sntp_send_request: Sending request to server\n"));
|
|
/* initialize request message */
|
|
sntp_initialize_request(sntpmsg);
|
|
/* send request */
|
|
udp_sendto(sntp_pcb, p, server_addr, SNTP_PORT);
|
|
pbuf_free(p);
|
|
|
|
/* set up receive timeout: try next server or retry on timeout */
|
|
sys_timeout((u32_t)SNTP_RECV_TIMEOUT * 1000, sntp_try_next_server, NULL);
|
|
#if SNTP_CHECK_RESPONSE >= 1
|
|
/* save server address to verify it in sntp_recv */
|
|
ip_addr_set(&sntp_last_server_address, server_addr);
|
|
#endif /* SNTP_CHECK_RESPONSE >= 1 */
|
|
} else {
|
|
LWIP_DEBUGF(SNTP_DEBUG_SERIOUS, ("sntp_send_request: Out of memory, trying again in %"U32_F" ms\n",
|
|
(u32_t)SNTP_RETRY_TIMEOUT));
|
|
/* out of memory: set up a timer to send a retry */
|
|
sys_timeout((u32_t)SNTP_RETRY_TIMEOUT, sntp_request, NULL);
|
|
}
|
|
}
|
|
|
|
#if SNTP_SERVER_DNS
|
|
/**
|
|
* DNS found callback when using DNS names as server address.
|
|
*/
|
|
static void
|
|
sntp_dns_found(const char* hostname, const ip_addr_t *ipaddr, void *arg)
|
|
{
|
|
LWIP_UNUSED_ARG(hostname);
|
|
LWIP_UNUSED_ARG(arg);
|
|
|
|
if (ipaddr != NULL) {
|
|
/* Address resolved, send request */
|
|
LWIP_DEBUGF(SNTP_DEBUG_STATE, ("sntp_dns_found: Server address resolved, sending request\n"));
|
|
sntp_send_request(ipaddr);
|
|
} else {
|
|
/* DNS resolving failed -> try another server */
|
|
LWIP_DEBUGF(SNTP_DEBUG_WARN_STATE, ("sntp_dns_found: Failed to resolve server address resolved, trying next server\n"));
|
|
sntp_try_next_server(NULL);
|
|
}
|
|
}
|
|
#endif /* SNTP_SERVER_DNS */
|
|
|
|
/**
|
|
* Send out an sntp request via raw API.
|
|
*
|
|
* @param arg is unused (only necessary to conform to sys_timeout)
|
|
*/
|
|
static void
|
|
sntp_request(void *arg)
|
|
{
|
|
ip_addr_t sntp_server_address;
|
|
err_t err;
|
|
|
|
LWIP_UNUSED_ARG(arg);
|
|
|
|
/* initialize SNTP server address */
|
|
#if SNTP_SERVER_DNS
|
|
err = dns_gethostbyname(sntp_server_addresses[sntp_current_server], &sntp_server_address,
|
|
sntp_dns_found, NULL);
|
|
if (err == ERR_INPROGRESS) {
|
|
/* DNS request sent, wait for sntp_dns_found being called */
|
|
LWIP_DEBUGF(SNTP_DEBUG_STATE, ("sntp_request: Waiting for server address to be resolved.\n"));
|
|
return;
|
|
}
|
|
#else /* SNTP_SERVER_DNS */
|
|
err = ipaddr_aton(sntp_server_addresses[sntp_current_server], &sntp_server_address)
|
|
? ERR_OK : ERR_ARG;
|
|
|
|
#endif /* SNTP_SERVER_DNS */
|
|
|
|
if (err == ERR_OK) {
|
|
sntp_send_request(&sntp_server_address);
|
|
} else {
|
|
/* address conversion failed, try another server */
|
|
LWIP_DEBUGF(SNTP_DEBUG_WARN_STATE, ("sntp_request: Invalid server address, trying next server.\n"));
|
|
sys_timeout((u32_t)SNTP_RETRY_TIMEOUT, sntp_try_next_server, NULL);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Initialize this module when using raw API.
|
|
* Send out request instantly or after SNTP_STARTUP_DELAY.
|
|
*/
|
|
void
|
|
sntp_init(void)
|
|
{
|
|
char *def_addr[] = {SNTP_SERVER_ADDRESS};
|
|
|
|
sntp_num_servers = 0;
|
|
sntp_set_servers(def_addr, sizeof(def_addr) / sizeof(char*));
|
|
|
|
SNTP_RESET_RETRY_TIMEOUT();
|
|
sntp_pcb = udp_new();
|
|
LWIP_ASSERT("Failed to allocate udp pcb for sntp client", sntp_pcb != NULL);
|
|
if (sntp_pcb != NULL) {
|
|
udp_recv(sntp_pcb, sntp_recv, NULL);
|
|
#if SNTP_STARTUP_DELAY
|
|
sys_timeout((u32_t)SNTP_STARTUP_DELAY, sntp_request, NULL);
|
|
#else
|
|
sntp_request(NULL);
|
|
#endif
|
|
}
|
|
}
|
|
|
|
#endif /* SNTP_SOCKET */
|
|
|
|
/* Additions to allow dynamically settings servers and update delay */
|
|
|
|
/**
|
|
* Set the NTP servers
|
|
*/
|
|
int sntp_set_servers(char *server_url[], int num_servers)
|
|
{
|
|
int i;
|
|
|
|
/* Check number of servers requested */
|
|
if (SNTP_NUM_SERVERS_SUPPORTED < num_servers) return -1;
|
|
|
|
/* Free previously allocated buffers */
|
|
for (i = sntp_num_servers - 1; i >= 0; i--) {
|
|
free(sntp_server_addresses[i]);
|
|
sntp_server_addresses[i] = NULL;
|
|
}
|
|
|
|
/* Allocate memory and copy servers */
|
|
for (i = 0; i < num_servers; i++) {
|
|
sntp_server_addresses[i] = strdup(server_url[i]);
|
|
if (!sntp_server_addresses[i]) {
|
|
sntp_num_servers = i;
|
|
return -2;
|
|
}
|
|
}
|
|
sntp_num_servers = num_servers;
|
|
return 0;
|
|
}
|
|
|
|
void sntp_set_update_delay(uint32_t ms)
|
|
{
|
|
sntp_update_delay = ms > 15000?ms:15000;
|
|
}
|
|
|
|
#endif /* LWIP_UDP */
|