ntp_auth.h

   1 /*
   2   chronyd/chronyc - Programs for keeping computer clocks accurate.
   3
   4  **********************************************************************
   5  * Copyright (C) Miroslav Lichvar  2019
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of version 2 of the GNU General Public License as
   9  * published by the Free Software Foundation.
  10  *
  11  * This program is distributed in the hope that it will be useful, but
  12  * WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License along
  17  * with this program; if not, write to the Free Software Foundation, Inc.,
  18  * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
  19  *
  20  **********************************************************************
  21
  22   =======================================================================
  23
  24   Header file for NTP authentication
  25   */
  26
  27 #ifndef GOT_NTP_AUTH_H
  28 #define GOT_NTP_AUTH_H
  29
  30 #include "addressing.h"
  31 #include "ntp.h"
  32
  33 typedef struct NAU_Instance_Record *NAU_Instance;
  34
  35 /* Create an authenticator instance in a specific mode */
  36 extern NAU_Instance NAU_CreateNoneInstance(void);
  37 extern NAU_Instance NAU_CreateSymmetricInstance(uint32_t key_id);
  38
  39 /* Destroy an instance */
  40 extern void NAU_DestroyInstance(NAU_Instance instance);
  41
  42 /* Check if an instance is not in the None mode */
  43 extern int NAU_IsAuthEnabled(NAU_Instance instance);
  44
  45 /* Get NTP version recommended for better compatibility */
  46 extern int NAU_GetSuggestedNtpVersion(NAU_Instance instance);
  47
  48 /* Perform operations necessary for NAU_GenerateRequestAuth() */
  49 extern int NAU_PrepareRequestAuth(NAU_Instance instance);
  50
  51 /* Adjust a transmit timestamp for an estimated minimum time it takes to call
  52    NAU_GenerateRequestAuth() */
  53 extern void NAU_AdjustRequestTimestamp(NAU_Instance instance, struct timespec *ts);
  54
  55 /* Extend a request with data required by the authentication mode */
  56 extern int NAU_GenerateRequestAuth(NAU_Instance instance, NTP_Packet *request,
  57                                    NTP_PacketInfo *info);
  58
  59 /* Parse a request or response to detect the authentication mode */
  60 extern int NAU_ParsePacket(NTP_Packet *packet, NTP_PacketInfo *info);
  61
  62 /* Verify that a request is authentic.  If it is not authentic and a non-zero
  63    kod code is returned, a KoD response should be sent back. */
  64 extern int NAU_CheckRequestAuth(NTP_Packet *request, NTP_PacketInfo *info, uint32_t *kod);
  65
  66 /* Adjust a transmit timestamp for an estimated minimum time it takes to call
  67    NAU_GenerateResponseAuth() */
  68 extern void NAU_AdjustResponseTimestamp(NTP_Packet *request, NTP_PacketInfo *info,
  69                                         struct timespec *ts);
  70
  71 /* Extend a response with data required by the authentication mode.  This
  72    function can be called only if the previous call of NAU_CheckRequestAuth()
  73    was on the same request. */
  74 extern int NAU_GenerateResponseAuth(NTP_Packet *request, NTP_PacketInfo *request_info,
  75                                     NTP_Packet *response, NTP_PacketInfo *response_info,
  76                                     NTP_Remote_Address *remote_addr,
  77                                     NTP_Local_Address *local_addr,
  78                                     uint32_t kod);
  79
  80 /* Verify that a response is authentic */
  81 extern int NAU_CheckResponseAuth(NAU_Instance instance, NTP_Packet *response,
  82                                  NTP_PacketInfo *info);
  83
  84 /* Change an authentication-specific address (e.g. after replacing a source) */
  85 extern void NAU_ChangeAddress(NAU_Instance instance, IPAddr *address);
  86
  87 #endif