716 lines
22 KiB
C
716 lines
22 KiB
C
/**
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* @file
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* SNTP client module
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*
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* This is simple "SNTP" client for the lwIP raw API.
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* It is a minimal implementation of SNTPv4 as specified in RFC 4330.
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*
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* For a list of some public NTP servers, see this link :
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* http://support.ntp.org/bin/view/Servers/NTPPoolServers
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*
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* @todo:
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* - set/change servers at runtime
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* - complete SNTP_CHECK_RESPONSE checks 3 and 4
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* - support broadcast/multicast mode?
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*/
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/*
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* Copyright (c) 2007-2009 Frédéric Bernon, Simon Goldschmidt
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* All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without modification,
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* are permitted provided that the following conditions are met:
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*
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* 1. Redistributions of source code must retain the above copyright notice,
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* this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright notice,
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* this list of conditions and the following disclaimer in the documentation
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* and/or other materials provided with the distribution.
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* 3. The name of the author may not be used to endorse or promote products
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* derived from this software without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
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* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
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* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
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* SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
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* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
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* OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
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* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
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* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
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* IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
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* OF SUCH DAMAGE.
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*
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* This file is part of the lwIP TCP/IP stack.
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*
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* Author: Frédéric Bernon, Simon Goldschmidt
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*/
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#include "apps/sntp/sntp.h"
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#include "lwip/opt.h"
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#include "lwip/timers.h"
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#include "lwip/udp.h"
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#include "lwip/dns.h"
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#include "lwip/ip_addr.h"
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#include "lwip/pbuf.h"
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#include "lwip/dhcp.h"
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#include <string.h>
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#include <time.h>
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#if LWIP_UDP
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/* Handle support for more than one server via SNTP_MAX_SERVERS */
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#if SNTP_MAX_SERVERS > 1
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#define SNTP_SUPPORT_MULTIPLE_SERVERS 1
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#else /* NTP_MAX_SERVERS > 1 */
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#define SNTP_SUPPORT_MULTIPLE_SERVERS 0
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#endif /* NTP_MAX_SERVERS > 1 */
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#if (SNTP_UPDATE_DELAY < 15000) && !defined(SNTP_SUPPRESS_DELAY_CHECK)
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#error "SNTPv4 RFC 4330 enforces a minimum update time of 15 seconds (define SNTP_SUPPRESS_DELAY_CHECK to disable this error)!"
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#endif
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/* Configure behaviour depending on microsecond or second precision */
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#ifdef SNTP_SET_SYSTEM_TIME_US
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#define SNTP_CALC_TIME_US 1
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#define SNTP_RECEIVE_TIME_SIZE 2
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#else
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#define SNTP_SET_SYSTEM_TIME_US(sec, us)
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#define SNTP_CALC_TIME_US 0
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#define SNTP_RECEIVE_TIME_SIZE 1
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#endif
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/* the various debug levels for this file */
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#define SNTP_DEBUG_TRACE (SNTP_DEBUG | LWIP_DBG_TRACE)
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#define SNTP_DEBUG_STATE (SNTP_DEBUG | LWIP_DBG_STATE)
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#define SNTP_DEBUG_WARN (SNTP_DEBUG | LWIP_DBG_LEVEL_WARNING)
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#define SNTP_DEBUG_WARN_STATE (SNTP_DEBUG | LWIP_DBG_LEVEL_WARNING | LWIP_DBG_STATE)
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#define SNTP_DEBUG_SERIOUS (SNTP_DEBUG | LWIP_DBG_LEVEL_SERIOUS)
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#define SNTP_ERR_KOD 1
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/* SNTP protocol defines */
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#define SNTP_MSG_LEN 48
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#define SNTP_OFFSET_LI_VN_MODE 0
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#define SNTP_LI_MASK 0xC0
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#define SNTP_LI_NO_WARNING 0x00
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#define SNTP_LI_LAST_MINUTE_61_SEC 0x01
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#define SNTP_LI_LAST_MINUTE_59_SEC 0x02
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#define SNTP_LI_ALARM_CONDITION 0x03 /* (clock not synchronized) */
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#define SNTP_VERSION_MASK 0x38
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#define SNTP_VERSION (4/* NTP Version 4*/<<3)
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#define SNTP_MODE_MASK 0x07
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#define SNTP_MODE_CLIENT 0x03
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#define SNTP_MODE_SERVER 0x04
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#define SNTP_MODE_BROADCAST 0x05
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#define SNTP_OFFSET_STRATUM 1
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#define SNTP_STRATUM_KOD 0x00
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#define SNTP_OFFSET_ORIGINATE_TIME 24
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#define SNTP_OFFSET_RECEIVE_TIME 32
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#define SNTP_OFFSET_TRANSMIT_TIME 40
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/* number of seconds between 1900 and 1970 (MSB=1)*/
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#define DIFF_SEC_1900_1970 (2208988800UL)
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/* number of seconds between 1970 and Feb 7, 2036 (6:28:16 UTC) (MSB=0) */
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#define DIFF_SEC_1970_2036 (2085978496UL)
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/**
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* SNTP packet format (without optional fields)
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* Timestamps are coded as 64 bits:
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* - 32 bits seconds since Jan 01, 1970, 00:00
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* - 32 bits seconds fraction (0-padded)
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* For future use, if the MSB in the seconds part is set, seconds are based
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* on Feb 07, 2036, 06:28:16.
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*/
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#ifdef PACK_STRUCT_USE_INCLUDES
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# include "arch/bpstruct.h"
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#endif
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PACK_STRUCT_BEGIN
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struct sntp_msg {
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PACK_STRUCT_FLD_8(u8_t li_vn_mode);
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PACK_STRUCT_FLD_8(u8_t stratum);
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PACK_STRUCT_FLD_8(u8_t poll);
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PACK_STRUCT_FLD_8(u8_t precision);
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PACK_STRUCT_FIELD(u32_t root_delay);
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PACK_STRUCT_FIELD(u32_t root_dispersion);
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PACK_STRUCT_FIELD(u32_t reference_identifier);
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PACK_STRUCT_FIELD(u32_t reference_timestamp[2]);
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PACK_STRUCT_FIELD(u32_t originate_timestamp[2]);
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PACK_STRUCT_FIELD(u32_t receive_timestamp[2]);
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PACK_STRUCT_FIELD(u32_t transmit_timestamp[2]);
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} PACK_STRUCT_STRUCT;
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PACK_STRUCT_END
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#ifdef PACK_STRUCT_USE_INCLUDES
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# include "arch/epstruct.h"
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#endif
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/* function prototypes */
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static void sntp_request(void *arg);
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/** The operating mode */
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static u8_t sntp_opmode;
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/** The UDP pcb used by the SNTP client */
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static struct udp_pcb* sntp_pcb;
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/** Names/Addresses of servers */
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struct sntp_server {
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#if SNTP_SERVER_DNS
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char* name;
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#endif /* SNTP_SERVER_DNS */
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ip_addr_t addr;
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};
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static struct sntp_server sntp_servers[SNTP_MAX_SERVERS];
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#if SNTP_GET_SERVERS_FROM_DHCP
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static u8_t sntp_set_servers_from_dhcp;
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#endif /* SNTP_GET_SERVERS_FROM_DHCP */
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#if SNTP_SUPPORT_MULTIPLE_SERVERS
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/** The currently used server (initialized to 0) */
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static u8_t sntp_current_server;
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#else /* SNTP_SUPPORT_MULTIPLE_SERVERS */
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#define sntp_current_server 0
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#endif /* SNTP_SUPPORT_MULTIPLE_SERVERS */
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#if SNTP_RETRY_TIMEOUT_EXP
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#define SNTP_RESET_RETRY_TIMEOUT() sntp_retry_timeout = SNTP_RETRY_TIMEOUT
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/** Retry time, initialized with SNTP_RETRY_TIMEOUT and doubled with each retry. */
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static u32_t sntp_retry_timeout;
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#else /* SNTP_RETRY_TIMEOUT_EXP */
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#define SNTP_RESET_RETRY_TIMEOUT()
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#define sntp_retry_timeout SNTP_RETRY_TIMEOUT
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#endif /* SNTP_RETRY_TIMEOUT_EXP */
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#if SNTP_CHECK_RESPONSE >= 1
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/** Saves the last server address to compare with response */
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static ip_addr_t sntp_last_server_address;
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#endif /* SNTP_CHECK_RESPONSE >= 1 */
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#if SNTP_CHECK_RESPONSE >= 2
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/** Saves the last timestamp sent (which is sent back by the server)
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* to compare against in response */
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static u32_t sntp_last_timestamp_sent[2];
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#endif /* SNTP_CHECK_RESPONSE >= 2 */
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/**
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* SNTP processing of received timestamp
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*/
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static void
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sntp_process(u32_t *receive_timestamp)
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{
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/* convert SNTP time (1900-based) to unix GMT time (1970-based)
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* if MSB is 0, SNTP time is 2036-based!
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*/
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u32_t rx_secs = ntohl(receive_timestamp[0]);
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int is_1900_based = ((rx_secs & 0x80000000) != 0);
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u32_t t = is_1900_based ? (rx_secs - DIFF_SEC_1900_1970) : (rx_secs + DIFF_SEC_1970_2036);
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time_t tim = t;
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#if SNTP_CALC_TIME_US
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u32_t us = ntohl(receive_timestamp[1]) / 4295;
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SNTP_SET_SYSTEM_TIME_US(t, us);
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/* display local time from GMT time */
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LWIP_DEBUGF(SNTP_DEBUG_TRACE, ("sntp_process: %s, %"U32_F" us", ctime(&tim), us));
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#else /* SNTP_CALC_TIME_US */
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/* change system time and/or the update the RTC clock */
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SNTP_SET_SYSTEM_TIME(t);
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/* display local time from GMT time */
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LWIP_DEBUGF(SNTP_DEBUG_TRACE, ("sntp_process: %s", ctime(&tim)));
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#endif /* SNTP_CALC_TIME_US */
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LWIP_UNUSED_ARG(tim);
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}
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/**
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* Initialize request struct to be sent to server.
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*/
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static void
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sntp_initialize_request(struct sntp_msg *req)
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{
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memset(req, 0, SNTP_MSG_LEN);
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req->li_vn_mode = SNTP_LI_NO_WARNING | SNTP_VERSION | SNTP_MODE_CLIENT;
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#if SNTP_CHECK_RESPONSE >= 2
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{
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u32_t sntp_time_sec, sntp_time_us;
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/* fill in transmit timestamp and save it in 'sntp_last_timestamp_sent' */
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SNTP_GET_SYSTEM_TIME(sntp_time_sec, sntp_time_us);
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sntp_last_timestamp_sent[0] = htonl(sntp_time_sec + DIFF_SEC_1900_1970);
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req->transmit_timestamp[0] = sntp_last_timestamp_sent[0];
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/* we send/save us instead of fraction to be faster... */
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sntp_last_timestamp_sent[1] = htonl(sntp_time_us);
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req->transmit_timestamp[1] = sntp_last_timestamp_sent[1];
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}
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#endif /* SNTP_CHECK_RESPONSE >= 2 */
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}
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/**
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* Retry: send a new request (and increase retry timeout).
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*
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* @param arg is unused (only necessary to conform to sys_timeout)
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*/
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static void
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sntp_retry(void* arg)
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{
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LWIP_UNUSED_ARG(arg);
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LWIP_DEBUGF(SNTP_DEBUG_STATE, ("sntp_retry: Next request will be sent in %"U32_F" ms\n",
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sntp_retry_timeout));
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/* set up a timer to send a retry and increase the retry delay */
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sys_timeout(sntp_retry_timeout, sntp_request, NULL);
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#if SNTP_RETRY_TIMEOUT_EXP
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{
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u32_t new_retry_timeout;
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/* increase the timeout for next retry */
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new_retry_timeout = sntp_retry_timeout << 1;
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/* limit to maximum timeout and prevent overflow */
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if ((new_retry_timeout <= SNTP_RETRY_TIMEOUT_MAX) &&
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(new_retry_timeout > sntp_retry_timeout)) {
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sntp_retry_timeout = new_retry_timeout;
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}
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}
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#endif /* SNTP_RETRY_TIMEOUT_EXP */
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}
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#if SNTP_SUPPORT_MULTIPLE_SERVERS
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/**
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* If Kiss-of-Death is received (or another packet parsing error),
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* try the next server or retry the current server and increase the retry
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* timeout if only one server is available.
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* (implicitly, SNTP_MAX_SERVERS > 1)
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*
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* @param arg is unused (only necessary to conform to sys_timeout)
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*/
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static void
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sntp_try_next_server(void* arg)
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{
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u8_t old_server, i;
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LWIP_UNUSED_ARG(arg);
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old_server = sntp_current_server;
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for (i = 0; i < SNTP_MAX_SERVERS - 1; i++) {
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sntp_current_server++;
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if (sntp_current_server >= SNTP_MAX_SERVERS) {
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sntp_current_server = 0;
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}
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if (!ip_addr_isany(&sntp_servers[sntp_current_server].addr)
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#if SNTP_SERVER_DNS
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|| (sntp_servers[sntp_current_server].name != NULL)
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#endif
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) {
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LWIP_DEBUGF(SNTP_DEBUG_STATE, ("sntp_try_next_server: Sending request to server %"U16_F"\n",
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(u16_t)sntp_current_server));
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/* new server: reset retry timeout */
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SNTP_RESET_RETRY_TIMEOUT();
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/* instantly send a request to the next server */
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sntp_request(NULL);
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return;
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}
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}
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/* no other valid server found */
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sntp_current_server = old_server;
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sntp_retry(NULL);
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}
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#else /* SNTP_SUPPORT_MULTIPLE_SERVERS */
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/* Always retry on error if only one server is supported */
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#define sntp_try_next_server sntp_retry
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#endif /* SNTP_SUPPORT_MULTIPLE_SERVERS */
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/** UDP recv callback for the sntp pcb */
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static void
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sntp_recv(void *arg, struct udp_pcb* pcb, struct pbuf *p, const ip_addr_t *addr, u16_t port)
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{
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u8_t mode;
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u8_t stratum;
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u32_t receive_timestamp[SNTP_RECEIVE_TIME_SIZE];
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err_t err;
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LWIP_UNUSED_ARG(arg);
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LWIP_UNUSED_ARG(pcb);
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/* packet received: stop retry timeout */
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sys_untimeout(sntp_try_next_server, NULL);
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sys_untimeout(sntp_request, NULL);
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err = ERR_ARG;
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#if SNTP_CHECK_RESPONSE >= 1
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/* check server address and port */
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if (((sntp_opmode != SNTP_OPMODE_POLL) || ip_addr_cmp(addr, &sntp_last_server_address)) &&
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(port == SNTP_PORT))
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#else /* SNTP_CHECK_RESPONSE >= 1 */
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LWIP_UNUSED_ARG(addr);
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LWIP_UNUSED_ARG(port);
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#endif /* SNTP_CHECK_RESPONSE >= 1 */
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{
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/* process the response */
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if (p->tot_len == SNTP_MSG_LEN) {
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pbuf_copy_partial(p, &mode, 1, SNTP_OFFSET_LI_VN_MODE);
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mode &= SNTP_MODE_MASK;
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/* if this is a SNTP response... */
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if (((sntp_opmode == SNTP_OPMODE_POLL) && (mode == SNTP_MODE_SERVER)) ||
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((sntp_opmode == SNTP_OPMODE_LISTENONLY) && (mode == SNTP_MODE_BROADCAST))) {
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pbuf_copy_partial(p, &stratum, 1, SNTP_OFFSET_STRATUM);
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if (stratum == SNTP_STRATUM_KOD) {
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/* Kiss-of-death packet. Use another server or increase UPDATE_DELAY. */
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err = SNTP_ERR_KOD;
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LWIP_DEBUGF(SNTP_DEBUG_STATE, ("sntp_recv: Received Kiss-of-Death\n"));
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} else {
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#if SNTP_CHECK_RESPONSE >= 2
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/* check originate_timetamp against sntp_last_timestamp_sent */
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u32_t originate_timestamp[2];
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pbuf_copy_partial(p, &originate_timestamp, 8, SNTP_OFFSET_ORIGINATE_TIME);
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if ((originate_timestamp[0] != sntp_last_timestamp_sent[0]) ||
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(originate_timestamp[1] != sntp_last_timestamp_sent[1]))
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{
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LWIP_DEBUGF(SNTP_DEBUG_WARN, ("sntp_recv: Invalid originate timestamp in response\n"));
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} else
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#endif /* SNTP_CHECK_RESPONSE >= 2 */
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/* @todo: add code for SNTP_CHECK_RESPONSE >= 3 and >= 4 here */
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{
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/* correct answer */
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err = ERR_OK;
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pbuf_copy_partial(p, &receive_timestamp, SNTP_RECEIVE_TIME_SIZE * 4, SNTP_OFFSET_TRANSMIT_TIME);
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}
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}
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} else {
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LWIP_DEBUGF(SNTP_DEBUG_WARN, ("sntp_recv: Invalid mode in response: %"U16_F"\n", (u16_t)mode));
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/* wait for correct response */
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err = ERR_TIMEOUT;
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}
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} else {
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LWIP_DEBUGF(SNTP_DEBUG_WARN, ("sntp_recv: Invalid packet length: %"U16_F"\n", p->tot_len));
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}
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}
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#if SNTP_CHECK_RESPONSE >= 1
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else {
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/* packet from wrong remote address or port, wait for correct response */
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err = ERR_TIMEOUT;
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}
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#endif /* SNTP_CHECK_RESPONSE >= 1 */
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pbuf_free(p);
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if (err == ERR_OK) {
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sntp_process(receive_timestamp);
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/* Set up timeout for next request (only if poll response was received)*/
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if (sntp_opmode == SNTP_OPMODE_POLL) {
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/* Correct response, reset retry timeout */
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SNTP_RESET_RETRY_TIMEOUT();
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sys_timeout((u32_t)SNTP_UPDATE_DELAY, sntp_request, NULL);
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LWIP_DEBUGF(SNTP_DEBUG_STATE, ("sntp_recv: Scheduled next time request: %"U32_F" ms\n",
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(u32_t)SNTP_UPDATE_DELAY));
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}
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} else if (err != ERR_TIMEOUT) {
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/* Errors are only processed in case of an explicit poll response */
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if (sntp_opmode == SNTP_OPMODE_POLL) {
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if (err == SNTP_ERR_KOD) {
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/* Kiss-of-death packet. Use another server or increase UPDATE_DELAY. */
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sntp_try_next_server(NULL);
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} else {
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/* another error, try the same server again */
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sntp_retry(NULL);
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}
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}
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}
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}
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/** Actually send an sntp request to a server.
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*
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* @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);
|
|
/* free the pbuf after sending it */
|
|
pbuf_free(p);
|
|
/* set up receive timeout: try next server or retry on timeout */
|
|
sys_timeout((u32_t)SNTP_RECV_TIMEOUT, 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.
|
|
*
|
|
* @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
|
|
if (sntp_servers[sntp_current_server].name) {
|
|
/* always resolve the name and rely on dns-internal caching & timeout */
|
|
ip_addr_set_zero(&sntp_servers[sntp_current_server].addr);
|
|
err = dns_gethostbyname(sntp_servers[sntp_current_server].name, &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 if (err == ERR_OK) {
|
|
sntp_servers[sntp_current_server].addr = sntp_server_address;
|
|
}
|
|
} else
|
|
#endif /* SNTP_SERVER_DNS */
|
|
{
|
|
sntp_server_address = sntp_servers[sntp_current_server].addr;
|
|
err = (ip_addr_isany_val(sntp_server_address)) ? ERR_ARG : ERR_OK;
|
|
}
|
|
|
|
if (err == ERR_OK) {
|
|
LWIP_DEBUGF(SNTP_DEBUG_TRACE, ("sntp_request: current server address is %s\n",
|
|
ipaddr_ntoa(&sntp_server_address)));
|
|
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.
|
|
* Send out request instantly or after SNTP_STARTUP_DELAY(_FUNC).
|
|
*/
|
|
void
|
|
sntp_init(void)
|
|
{
|
|
#ifdef SNTP_SERVER_ADDRESS
|
|
#if SNTP_SERVER_DNS
|
|
sntp_setservername(0, SNTP_SERVER_ADDRESS);
|
|
#else
|
|
#error SNTP_SERVER_ADDRESS string not supported SNTP_SERVER_DNS==0
|
|
#endif
|
|
#endif /* SNTP_SERVER_ADDRESS */
|
|
|
|
if (sntp_pcb == NULL) {
|
|
sntp_pcb = udp_new_ip_type(IPADDR_TYPE_ANY);
|
|
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_opmode == SNTP_OPMODE_POLL) {
|
|
SNTP_RESET_RETRY_TIMEOUT();
|
|
#if SNTP_STARTUP_DELAY
|
|
sys_timeout((u32_t)SNTP_STARTUP_DELAY_FUNC, sntp_request, NULL);
|
|
#else
|
|
sntp_request(NULL);
|
|
#endif
|
|
} else if (sntp_opmode == SNTP_OPMODE_LISTENONLY) {
|
|
ip_set_option(sntp_pcb, SOF_BROADCAST);
|
|
udp_bind(sntp_pcb, IP_ANY_TYPE, SNTP_PORT);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Stop this module.
|
|
*/
|
|
void
|
|
sntp_stop(void)
|
|
{
|
|
if (sntp_pcb != NULL) {
|
|
sys_untimeout(sntp_request, NULL);
|
|
udp_remove(sntp_pcb);
|
|
sntp_pcb = NULL;
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Get enabled state.
|
|
*/
|
|
u8_t sntp_enabled(void)
|
|
{
|
|
return (sntp_pcb != NULL)? 1 : 0;
|
|
}
|
|
|
|
/**
|
|
* Sets the operating mode.
|
|
* @param operating_mode one of the available operating modes
|
|
*/
|
|
void
|
|
sntp_setoperatingmode(u8_t operating_mode)
|
|
{
|
|
LWIP_ASSERT("Invalid operating mode", operating_mode <= SNTP_OPMODE_LISTENONLY);
|
|
LWIP_ASSERT("Operating mode must not be set while SNTP client is running", sntp_pcb == NULL);
|
|
sntp_opmode = operating_mode;
|
|
}
|
|
|
|
/**
|
|
* Gets the operating mode.
|
|
*/
|
|
u8_t
|
|
sntp_getoperatingmode(void)
|
|
{
|
|
return sntp_opmode;
|
|
}
|
|
|
|
#if SNTP_GET_SERVERS_FROM_DHCP
|
|
/**
|
|
* Config SNTP server handling by IP address, name, or DHCP; clear table
|
|
* @param set_servers_from_dhcp enable or disable getting server addresses from dhcp
|
|
*/
|
|
void
|
|
sntp_servermode_dhcp(int set_servers_from_dhcp)
|
|
{
|
|
u8_t new_mode = set_servers_from_dhcp ? 1 : 0;
|
|
if (sntp_set_servers_from_dhcp != new_mode) {
|
|
sntp_set_servers_from_dhcp = new_mode;
|
|
}
|
|
}
|
|
#endif /* SNTP_GET_SERVERS_FROM_DHCP */
|
|
|
|
/**
|
|
* Initialize one of the NTP servers by IP address
|
|
*
|
|
* @param numdns the index of the NTP server to set must be < SNTP_MAX_SERVERS
|
|
* @param dnsserver IP address of the NTP server to set
|
|
*/
|
|
void
|
|
sntp_setserver(u8_t idx, const ip_addr_t *server)
|
|
{
|
|
if (idx < SNTP_MAX_SERVERS) {
|
|
if (server != NULL) {
|
|
sntp_servers[idx].addr = (*server);
|
|
} else {
|
|
ip_addr_set_zero(&sntp_servers[idx].addr);
|
|
}
|
|
#if SNTP_SERVER_DNS
|
|
sntp_servers[idx].name = NULL;
|
|
#endif
|
|
}
|
|
}
|
|
|
|
#if LWIP_DHCP && SNTP_GET_SERVERS_FROM_DHCP
|
|
/**
|
|
* Initialize one of the NTP servers by IP address, required by DHCP
|
|
*
|
|
* @param numdns the index of the NTP server to set must be < SNTP_MAX_SERVERS
|
|
* @param dnsserver IP address of the NTP server to set
|
|
*/
|
|
void
|
|
dhcp_set_ntp_servers(u8_t num, const ip4_addr_t *server)
|
|
{
|
|
LWIP_DEBUGF(SNTP_DEBUG_TRACE, ("sntp: %s %u.%u.%u.%u as NTP server #%u via DHCP\n",
|
|
(sntp_set_servers_from_dhcp ? "Got" : "Rejected"),
|
|
ip4_addr1(server), ip4_addr2(server), ip4_addr3(server), ip4_addr4(server), num));
|
|
if (sntp_set_servers_from_dhcp && num) {
|
|
u8_t i;
|
|
for (i = 0; (i < num) && (i < SNTP_MAX_SERVERS); i++) {
|
|
ip_addr_t addr;
|
|
ip_addr_copy_from_ip4(addr, server[i]);
|
|
sntp_setserver(i, &addr);
|
|
}
|
|
for (i = num; i < SNTP_MAX_SERVERS; i++) {
|
|
sntp_setserver(i, NULL);
|
|
}
|
|
}
|
|
}
|
|
#endif /* LWIP_DHCP && SNTP_GET_SERVERS_FROM_DHCP */
|
|
|
|
/**
|
|
* Obtain one of the currently configured by IP address (or DHCP) NTP servers
|
|
*
|
|
* @param numdns the index of the NTP server
|
|
* @return IP address of the indexed NTP server or "ip_addr_any" if the NTP
|
|
* server has not been configured by address (or at all).
|
|
*/
|
|
ip_addr_t
|
|
sntp_getserver(u8_t idx)
|
|
{
|
|
if (idx < SNTP_MAX_SERVERS) {
|
|
return sntp_servers[idx].addr;
|
|
}
|
|
return *IP_ADDR_ANY;
|
|
}
|
|
|
|
#if SNTP_SERVER_DNS
|
|
/**
|
|
* Initialize one of the NTP servers by name
|
|
*
|
|
* @param numdns the index of the NTP server to set must be < SNTP_MAX_SERVERS
|
|
* @param dnsserver DNS name of the NTP server to set, to be resolved at contact time
|
|
*/
|
|
void
|
|
sntp_setservername(u8_t idx, char *server)
|
|
{
|
|
if (idx < SNTP_MAX_SERVERS) {
|
|
sntp_servers[idx].name = server;
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Obtain one of the currently configured by name NTP servers.
|
|
*
|
|
* @param numdns the index of the NTP server
|
|
* @return IP address of the indexed NTP server or NULL if the NTP
|
|
* server has not been configured by name (or at all)
|
|
*/
|
|
char *
|
|
sntp_getservername(u8_t idx)
|
|
{
|
|
if (idx < SNTP_MAX_SERVERS) {
|
|
return sntp_servers[idx].name;
|
|
}
|
|
return NULL;
|
|
}
|
|
#endif /* SNTP_SERVER_DNS */
|
|
|
|
#endif /* LWIP_UDP */
|
|
|