DWS/chrony
1
0
Fork 0
mirror of https://gitlab.com/chrony/chrony.git synced 2025-12-03 16:35:06 -05:00
Code Issues Packages Projects Releases Wiki Activity

ntp: refactor NTP_Packet structure for extension fields

Browse Source
This commit is contained in:
Miroslav Lichvar
2019-02-15 16:18:39 +01:00
parent 5a09adebfd
commit d29bef93e9
8 changed files with 58 additions and 66 deletions
Download Patch File Download Diff File Expand all files Collapse all files

31
ntp.h
View File

@@ -47,18 +47,18 @@ typedef uint32_t NTP_int32;
/* Maximum stratum number (infinity) */
#define NTP_MAX_STRATUM 16
/* The minimum valid length of an extension field */
#define NTP_MIN_EXTENSION_LENGTH 16
/* The maximum assumed length of all extension fields in received
packets (RFC 5905 doesn't specify a limit on length or number of
extension fields in one packet) */
#define NTP_MAX_EXTENSIONS_LENGTH 1024
/* 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)
@@ -93,21 +93,10 @@ typedef struct {
NTP_int64 receive_ts;
NTP_int64 transmit_ts;
/* Optional extension fields, we don't send packets with them yet */
/* uint8_t extensions[] */
/* Optional message authentication code (MAC) */
NTP_int32 auth_keyid;
uint8_t auth_data[NTP_MAX_MAC_LENGTH - 4];
uint8_t extensions[NTP_MAX_EXTENSIONS_LENGTH];
} NTP_Packet;
#define NTP_NORMAL_PACKET_LENGTH (int)offsetof(NTP_Packet, auth_keyid)
/* The buffer used to hold a datagram read from the network */
typedef struct {
NTP_Packet ntp_pkt;
uint8_t extensions[NTP_MAX_EXTENSIONS_LENGTH];
} NTP_Receive_Buffer;
#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)