summaryrefslogtreecommitdiffstats
path: root/ntp.h
diff options
context:
space:
mode:
Diffstat (limited to 'ntp.h')
-rw-r--r--ntp.h200
1 files changed, 200 insertions, 0 deletions
diff --git a/ntp.h b/ntp.h
new file mode 100644
index 0000000..165adbc
--- /dev/null
+++ b/ntp.h
@@ -0,0 +1,200 @@
+/*
+ chronyd/chronyc - Programs for keeping computer clocks accurate.
+
+ **********************************************************************
+ * Copyright (C) Richard P. Curnow 1997-2003
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ **********************************************************************
+
+ =======================================================================
+
+ Header file containing common NTP bits and pieces
+ */
+
+#ifndef GOT_NTP_H
+#define GOT_NTP_H
+
+#include "sysincl.h"
+
+#include "hash.h"
+
+typedef struct {
+ uint32_t hi;
+ uint32_t lo;
+} NTP_int64;
+
+typedef uint32_t NTP_int32;
+
+/* The UDP port number used by NTP */
+#define NTP_PORT 123
+
+/* The NTP protocol version that we support */
+#define NTP_VERSION 4
+
+/* Maximum stratum number (infinity) */
+#define NTP_MAX_STRATUM 16
+
+/* Invalid stratum number */
+#define NTP_INVALID_STRATUM 0
+
+/* The minimum and maximum supported length of MAC */
+#define NTP_MIN_MAC_LENGTH (4 + 16)
+#define NTP_MAX_MAC_LENGTH (4 + MAX_HASH_LENGTH)
+
+/* The minimum valid length of an extension field */
+#define NTP_MIN_EF_LENGTH 16
+
+/* The maximum assumed length of all extension fields in an NTP packet,
+ including a MAC (RFC 5905 doesn't specify a limit on length or number of
+ extension fields in one packet) */
+#define NTP_MAX_EXTENSIONS_LENGTH (1024 + NTP_MAX_MAC_LENGTH)
+
+/* The maximum length of MAC in NTPv4 packets which allows deterministic
+ parsing of extension fields (RFC 7822) */
+#define NTP_MAX_V4_MAC_LENGTH (4 + 20)
+
+/* Type definition for leap bits */
+typedef enum {
+ LEAP_Normal = 0,
+ LEAP_InsertSecond = 1,
+ LEAP_DeleteSecond = 2,
+ LEAP_Unsynchronised = 3
+} NTP_Leap;
+
+typedef enum {
+ MODE_UNDEFINED = 0,
+ MODE_ACTIVE = 1,
+ MODE_PASSIVE = 2,
+ MODE_CLIENT = 3,
+ MODE_SERVER = 4,
+ MODE_BROADCAST = 5
+} NTP_Mode;
+
+typedef struct {
+ uint8_t lvm;
+ uint8_t stratum;
+ int8_t poll;
+ int8_t precision;
+ NTP_int32 root_delay;
+ NTP_int32 root_dispersion;
+ NTP_int32 reference_id;
+ NTP_int64 reference_ts;
+ NTP_int64 originate_ts;
+ NTP_int64 receive_ts;
+ NTP_int64 transmit_ts;
+
+ uint8_t extensions[NTP_MAX_EXTENSIONS_LENGTH];
+} NTP_Packet;
+
+#define NTP_HEADER_LENGTH (int)offsetof(NTP_Packet, extensions)
+
+/* Macros to work with the lvm field */
+#define NTP_LVM_TO_LEAP(lvm) (((lvm) >> 6) & 0x3)
+#define NTP_LVM_TO_VERSION(lvm) (((lvm) >> 3) & 0x7)
+#define NTP_LVM_TO_MODE(lvm) ((lvm) & 0x7)
+#define NTP_LVM(leap, version, mode) \
+ ((((leap) << 6) & 0xc0) | (((version) << 3) & 0x38) | ((mode) & 0x07))
+
+/* Special NTP reference IDs */
+#define NTP_REFID_UNSYNC 0x0UL
+#define NTP_REFID_LOCAL 0x7F7F0101UL /* 127.127.1.1 */
+#define NTP_REFID_SMOOTH 0x7F7F01FFUL /* 127.127.1.255 */
+
+/* Non-authentication extension fields and corresponding internal flags */
+
+#define NTP_EF_EXP_MONO_ROOT 0xF323
+#define NTP_EF_EXP_NET_CORRECTION 0xF324
+
+#define NTP_EF_FLAG_EXP_MONO_ROOT 0x1
+#define NTP_EF_FLAG_EXP_NET_CORRECTION 0x2
+
+/* Pre-NTPv5 experimental extension field */
+typedef struct {
+ uint32_t magic;
+ NTP_int32 root_delay;
+ NTP_int32 root_dispersion;
+ NTP_int64 mono_receive_ts;
+ uint32_t mono_epoch;
+} NTP_EFExpMonoRoot;
+
+#define NTP_EF_EXP_MONO_ROOT_MAGIC 0xF5BEDD9AU
+
+/* Experimental extension field to provide PTP corrections */
+typedef struct {
+ uint32_t magic;
+ NTP_int64 correction;
+ uint32_t reserved[3];
+} NTP_EFExpNetCorrection;
+
+#define NTP_EF_EXP_NET_CORRECTION_MAGIC 0x07AC2CEBU
+
+/* Authentication extension fields */
+
+#define NTP_EF_NTS_UNIQUE_IDENTIFIER 0x0104
+#define NTP_EF_NTS_COOKIE 0x0204
+#define NTP_EF_NTS_COOKIE_PLACEHOLDER 0x0304
+#define NTP_EF_NTS_AUTH_AND_EEF 0x0404
+
+/* Enumeration for authentication modes of NTP packets */
+typedef enum {
+ NTP_AUTH_NONE = 0, /* No authentication */
+ NTP_AUTH_SYMMETRIC, /* NTP MAC or CMAC using a symmetric key
+ (RFC 1305, RFC 5905, RFC 8573) */
+ NTP_AUTH_MSSNTP, /* MS-SNTP authenticator field */
+ NTP_AUTH_MSSNTP_EXT, /* MS-SNTP extended authenticator field */
+ NTP_AUTH_NTS, /* Network Time Security (RFC 8915) */
+} NTP_AuthMode;
+
+/* Structure describing an NTP packet */
+typedef struct {
+ int length;
+ int version;
+ NTP_Mode mode;
+
+ int ext_fields;
+ int ext_field_flags;
+
+ struct {
+ NTP_AuthMode mode;
+ struct {
+ int start;
+ int length;
+ uint32_t key_id;
+ } mac;
+ } auth;
+} NTP_PacketInfo;
+
+/* Structure used to save NTP measurements. time is the local time at which
+ the sample is to be considered to have been made and offset is the offset at
+ the time (positive indicates that the local clock is slow relative to the
+ source). root_delay/root_dispersion include peer_delay/peer_dispersion. */
+typedef struct {
+ struct timespec time;
+ double offset;
+ double peer_delay;
+ double peer_dispersion;
+ double root_delay;
+ double root_dispersion;
+} NTP_Sample;
+
+/* Possible sources of timestamps */
+typedef enum {
+ NTP_TS_DAEMON = 0,
+ NTP_TS_KERNEL,
+ NTP_TS_HARDWARE
+} NTP_Timestamp_Source;
+
+#endif /* GOT_NTP_H */