sntp: initial import

Makefile.dep

@@ -19,6 +19,11 @@ ifneq (,$(filter nhdp,$(USEMODULE)))
   USEMODULE += oonf_rfc5444
 endif
 
+ifneq (,$(filter sntp,$(USEMODULE)))
+  USEMODULE += gnrc_sock_udp
+  USEMODULE += xtimer
+endif
+
 ifneq (,$(filter gnrc_netdev_default,$(USEMODULE)))
   USEMODULE += gnrc_netif
   USEMODULE += gnrc_netdev2

sys/Makefile

@@ -89,6 +89,10 @@ ifneq (,$(filter gnrc_uhcpc,$(USEMODULE)))
     DIRS += net/gnrc/application_layer/uhcpc
 endif
 
+ifneq (,$(filter sntp,$(USEMODULE)))
+    DIRS += net/application_layer/sntp
+endif
+
 ifneq (,$(filter netopt,$(USEMODULE)))
     DIRS += net/crosslayer/netopt
 endif

sys/include/net/ntp_packet.h

@@ -0,0 +1,167 @@
+/*
+ * Copyright (C) 2016 Luminița Lăzărescu <cluminita.lazarescu@gmail.com>
+ *
+ * This file is subject to the terms and conditions of the GNU Lesser
+ * General Public License v2.1. See the file LICENSE in the top level
+ * directory for more details.
+ */
+
+/**
+ * @defgroup    net_ntp_packet NTP Packet
+ * @ingroup     net
+ * @brief       The NTP packet module provides functionality to manipulate the NTP header
+ * @{
+ *
+ * @file
+ * @brief       NTP packet definitions
+ *
+ * @author      Luminița Lăzărescu <cluminita.lazarescu@gmail.com>
+ * @author      Martine Lenders <m.lenders@fu-berlin.de>
+ */
+
+#ifndef NTP_PACKET_H_
+#define NTP_PACKET_H_
+
+#include <stdint.h>
+#include "byteorder.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/**
+ * @{
+ * @brief Bit positions and masks for ntp_packet_t::li_vn_mode
+ */
+/**
+ * @brief Leap indicator position
+ */
+#define NTP_PACKET_LI_POS    (6U)
+#define NTP_PACKET_LI_MASK   (0xc0)     /**< leap indicator mask */
+#define NTP_PACKET_VN_POS    (3U)       /**< version position */
+#define NTP_PACKET_VN_MASK   (0x38)     /**< version mask */
+#define NTP_PACKET_MODE_MASK (0x07)     /**< mode mask */
+/** @} */
+
+#define NTP_VERSION          (4U)       /**< NTP version */
+#define NTP_PORT             (123U)     /**< NTP port number */
+
+/**
+ * @brief NTP modes
+ */
+typedef enum {
+    NTP_MODE_RESERVED = 0,  /**< reserved */
+    NTP_MODE_SYM_ACTIVE,    /**< symmetric active */
+    NTP_MODE_SYM_PASSIVE,   /**< symmetric passive */
+    NTP_MODE_CLIENT,        /**< client */
+    NTP_MODE_SERVER,        /**< server */
+    NTP_MODE_BROADCAST,     /**< broadcast */
+    NTP_MODE_PRIV           /**< reserved for private use */
+} ntp_mode_t;
+
+/**
+ * @brief NTP timestamp
+ *
+ * @see   [RFC 5905, Section 6](https://tools.ietf.org/html/rfc5905#section-6)
+ */
+typedef struct __attribute__((packed)) {
+    network_uint32_t seconds;           /**< seconds since 1 January 1900 00:00 UTC */
+    network_uint32_t fraction;          /**< fraction of seconds in 232 picoseconds */
+} ntp_timestamp_t;
+
+/**
+ * @brief NTP packet
+ *
+ * @see   [RFC 5905, Section 7.3](https://tools.ietf.org/html/rfc5905#section-7.3)
+ */
+typedef struct __attribute__((packed)) {
+    uint8_t li_vn_mode;                 /**< leap indicator, version and mode */
+    uint8_t stratum;                    /**< stratum */
+    uint8_t poll;                       /**< poll in log2 seconds */
+    uint8_t precision;                  /**< precision in log2 seconds */
+    network_uint32_t root_delay;        /**< root delay in NTP short format */
+    network_uint32_t root_dispersion;   /**< root dispersion in NTP short format */
+    network_uint32_t reference_id;      /**< reference ID */
+    ntp_timestamp_t reference;          /**< reference timestamp */
+    ntp_timestamp_t origin;             /**< origin timesptamp */
+    ntp_timestamp_t receive;            /**< receive timestamp */
+    ntp_timestamp_t transmit;           /**< transmit timestamp */
+} ntp_packet_t;
+
+/**
+ * @brief Set leap indicator in a NTP packet
+ *
+ * @param[in] packet    The NTP packet
+ * @param[in] li        Leap indicator
+ */
+static inline void ntp_packet_set_li(ntp_packet_t *packet, uint8_t li)
+{
+    packet->li_vn_mode &= ~NTP_PACKET_LI_MASK;
+    packet->li_vn_mode |= li << NTP_PACKET_LI_POS;
+}
+
+/**
+ * @brief Set version in a NTP packet
+ *
+ * @param[in] packet    The NTP packet
+ */
+static inline void ntp_packet_set_vn(ntp_packet_t *packet)
+{
+    packet->li_vn_mode &= ~NTP_PACKET_VN_MASK;
+    packet->li_vn_mode |= (NTP_VERSION << NTP_PACKET_VN_POS) & NTP_PACKET_VN_MASK;
+}
+
+/**
+ * @brief Set mode in a NTP packet
+ *
+ * @param[in] packet    The NTP packet
+ * @param[in] mode      Mode
+ */
+static inline void ntp_packet_set_mode(ntp_packet_t *packet, ntp_mode_t mode)
+{
+    packet->li_vn_mode &= ~NTP_PACKET_MODE_MASK;
+    packet->li_vn_mode |= mode & NTP_PACKET_MODE_MASK;
+}
+
+/**
+ * @brief Get leap indicator from a NTP packet
+ *
+ * @param[in] packet    The NTP packet
+ *
+ * @return The leap indicator of @p packet
+ */
+static inline uint8_t ntp_packet_get_li(ntp_packet_t *packet)
+{
+    return (packet->li_vn_mode & NTP_PACKET_LI_MASK) >> NTP_PACKET_LI_POS;
+}
+
+/**
+ * @brief Get version from a NTP packet
+ *
+ * @param[in] packet    The NTP packet
+ *
+ * @return The version of @p packet
+ */
+static inline uint8_t ntp_packet_get_vn(ntp_packet_t *packet)
+{
+    return (packet->li_vn_mode & NTP_PACKET_VN_MASK) >> NTP_PACKET_VN_POS;
+}
+
+/**
+ * @brief Get mode from a NTP packet
+ *
+ * @param[in] packet   The NTP packet
+ *
+ * @return The version of @p packet
+ */
+static inline ntp_mode_t ntp_packet_get_mode(ntp_packet_t *packet)
+{
+    return (packet->li_vn_mode & NTP_PACKET_MODE_MASK);
+}
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* NTP_PACKET_H_ */
+/** @} */

sys/include/net/sntp.h

@@ -0,0 +1,55 @@
+/*
+ * Copyright (C) 2016 Luminița Lăzărescu <cluminita.lazarescu@gmail.com>
+ *
+ * This file is subject to the terms and conditions of the GNU Lesser
+ * General Public License v2.1. See the file LICENSE in the top level
+ * directory for more details.
+ */
+
+/**
+ * @defgroup    net_sntp Simple Network Time Protocol
+ * @ingroup     net
+ * @brief       Simple Network Time Protocol (SNTP) implementation
+ * @{
+ *
+ * @file
+ * @brief       SNTP definitions
+ *
+ * @author      Luminița Lăzărescu <cluminita.lazarescu@gmail.com>
+ * @author      Martine Lenders <m.lenders@fu-berlin.de>
+ */
+
+#ifndef SNTP_H_
+#define SNTP_H_
+
+#include <stdint.h>
+#include "net/sock/udp.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/**
+ * @brief Synchronize with time server
+ *
+ * @param[in] server    The time server
+ * @param[in] timeout   Timeout for the server response
+ *
+ * @return 0 on success
+ * @return Negative number on error
+ */
+int sntp_sync(sock_udp_ep_t *server, uint32_t timeout);
+
+/**
+ * @brief Get real time offset from system time as returned by @ref xtimer_now64()
+ *
+ * @return Real time offset in microseconds relative to 1900-01-01 00:00 UTC
+ */
+int64_t sntp_get_offset(void);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* SNTP_H_ */
+/** @} */

sys/net/application_layer/sntp/Makefile

@@ -0,0 +1,2 @@
+MODULE = sntp
+include $(RIOTBASE)/Makefile.base

sys/net/application_layer/sntp/sntp.c

@@ -0,0 +1,89 @@
+/*
+ * Copyright (C) 2016 Luminița Lăzărescu <cluminita.lazarescu@gmail.com>
+ *
+ * This file is subject to the terms and conditions of the GNU Lesser
+ * General Public License v2.1. See the file LICENSE in the top level
+ * directory for more details.
+ */
+
+/**
+ * @{
+ *
+ * @file
+ * @brief       SNTP implementation
+ *
+ * @author      Luminița Lăzărescu <cluminita.lazarescu@gmail.com>
+ * @author      Martine Lenders <m.lenders@fu-berlin.de>
+ *
+ * @}
+ */
+
+#include <string.h>
+#include "net/sntp.h"
+#include "net/ntp_packet.h"
+#include "net/sock/udp.h"
+#include "xtimer.h"
+#include "mutex.h"
+#include "byteorder.h"
+
+#define ENABLE_DEBUG    (0)
+#include "debug.h"
+
+static sock_udp_t _sntp_sock;
+static int64_t _sntp_offset = 0;
+static mutex_t _sntp_mutex = MUTEX_INIT;
+static ntp_packet_t _sntp_packet;
+
+int sntp_sync(sock_udp_ep_t *server, uint32_t timeout)
+{
+    int result;
+
+    mutex_lock(&_sntp_mutex);
+    if ((result = sock_udp_create(&_sntp_sock,
+                                  NULL,
+                                  server,
+                                  0)) < 0) {
+        DEBUG("Error creating UDP sock\n");
+        mutex_unlock(&_sntp_mutex);
+        return result;
+    }
+    memset(&_sntp_packet, 0, sizeof(_sntp_packet));
+    ntp_packet_set_vn(&_sntp_packet);
+    ntp_packet_set_mode(&_sntp_packet, NTP_MODE_CLIENT);
+
+    if ((result = (int)sock_udp_send(&_sntp_sock,
+                                     &_sntp_packet,
+                                     sizeof(_sntp_packet),
+                                     NULL)) < 0) {
+        DEBUG("Error sending message\n");
+        sock_udp_close(&_sntp_sock);
+        mutex_unlock(&_sntp_mutex);
+        return result;
+    }
+    if ((result = (int)sock_udp_recv(&_sntp_sock,
+                                     &_sntp_packet,
+                                     sizeof(_sntp_packet),
+                                     timeout,
+                                     NULL)) < 0) {
+        DEBUG("Error receiving message\n");
+        sock_udp_close(&_sntp_sock);
+        mutex_unlock(&_sntp_mutex);
+        return result;
+    }
+    sock_udp_close(&_sntp_sock);
+    _sntp_offset = (byteorder_ntohl(_sntp_packet.transmit.seconds) * SEC_IN_USEC) +
+                   ((byteorder_ntohl(_sntp_packet.transmit.fraction) * 232)
+                   / 1000000) - xtimer_now64();
+    mutex_unlock(&_sntp_mutex);
+    return 0;
+}
+
+int64_t sntp_get_offset(void)
+{
+    int64_t result;
+
+    mutex_lock(&_sntp_mutex);
+    result = _sntp_offset;
+    mutex_unlock(&_sntp_mutex);
+    return result;
+}

sys/shell/commands/Makefile

@@ -66,6 +66,9 @@ endif
 ifneq (,$(filter ccn-lite-utils,$(USEMODULE)))
   SRC += sc_ccnl.c
 endif
+ifneq (,$(filter sntp,$(USEMODULE)))
+  SRC += sc_sntp.c
+endif
 
 # TODO
 # Conditional building not possible at the moment due to

sys/shell/commands/sc_sntp.c

@@ -0,0 +1,52 @@
+/*
+ * Copyright (C) 2016 Luminița Lăzărescu <cluminita.lazarescu@gmail.com>
+ *
+ * This file is subject to the terms and conditions of the GNU Lesser
+ * General Public License v2.1. See the file LICENSE in the top level
+ * directory for more details.
+ */
+
+/**
+ * @ingroup     sys_shell_commands
+ * @{
+ *
+ * @file
+ * @brief       Prints the real time offset from the system time
+ *
+ * @author      Luminița Lăzărescu <cluminita.lazarescu@gmail.com>
+ */
+
+
+#include "net/sntp.h"
+#include "net/ntp_packet.h"
+#include "net/af.h"
+#include "net/ipv6/addr.h"
+
+#define _DEFAULT_TIMEOUT (5000U);
+
+static void _usage(char *cmd)
+{
+    printf("Usage: %s <server addr> [<timeout>]\n", cmd);
+    puts("default: timeout = 5000");
+}
+
+int _ntpdate(int argc, char **argv)
+{
+    uint32_t timeout = _DEFAULT_TIMEOUT;
+
+    if (argc < 2) {
+        _usage(argv[0]);
+        return 1;
+    }
+    sock_udp_ep_t server = { .port = NTP_PORT, .family = AF_INET6 };
+    ipv6_addr_from_str((ipv6_addr_t *)&server.addr, argv[1]);
+    if (argc > 2) {
+        timeout = atoi(argv[2]);
+    }
+    if (sntp_sync(&server, timeout) < 0) {
+        puts("Error in synchronization");
+        return 1;
+    }
+    printf("Offset: %i\n", (int)sntp_get_offset());
+    return 0;
+}

sys/shell/commands/shell_commands.c

@@ -129,6 +129,10 @@ extern int _ccnl_interest(int argc, char **argv);
 extern int _ccnl_fib(int argc, char **argv);
 #endif
 
+#ifdef MODULE_SNTP
+extern int _ntpdate(int argc, char **argv);
+#endif
+
 const shell_command_t _shell_command_list[] = {
     {"reboot", "Reboot the node", _reboot_handler},
 #ifdef MODULE_CONFIG
@@ -209,10 +213,13 @@ const shell_command_t _shell_command_list[] = {
     {"saul", "interact with sensors and actuators using SAUL", _saul },
 #endif
 #ifdef MODULE_CCN_LITE_UTILS
-    { "ccnl_open", "opens an interface or socket", _ccnl_open},
-    { "ccnl_int", "sends an interest", _ccnl_interest},
-    { "ccnl_cont", "create content and populated it", _ccnl_content},
-    { "ccnl_fib", "shows or modifies the CCN-Lite FIB", _ccnl_fib},
+    { "ccnl_open", "opens an interface or socket", _ccnl_open },
+    { "ccnl_int", "sends an interest", _ccnl_interest },
+    { "ccnl_cont", "create content and populated it", _ccnl_content },
+    { "ccnl_fib", "shows or modifies the CCN-Lite FIB", _ccnl_fib },
+#endif
+#ifdef MODULE_SNTP
+    { "ntpdate", "synchronizes with a remote time server", _ntpdate },
 #endif
     {NULL, NULL, NULL}
 };