r5 - 2018-04-28 - 09:57:44 - HarlanStennYou are here: NTP >  Dev Web > DevelopmentIssues > ConfigurationAndAuthorizationLevelsForNtpd
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Configuration and Authorization Levels for ntpd

Related Topics: NtpVariablesAndNtpq

Background and History


BrianUtterback suggests we need to classify operations on data types as follows:

  • public-read-only
  • private-read-only
  • safe-write
  • unsafe-write


In the context of prior discussions, safe-write would be any ntpq/ntpdc operation that changes the ntpd state, such as ntpq -c ":config tos minsane 3" except those segregated as particularly dangerous, risking not just timekeeping but the system on which it runs, including:

ntpq -c "saveconfig /path/to/overwrite"
ntpq -c ":config logfile /path/to/appendfile"
ntpq -c ":config enable stats"
ntpq -c ":config filegen ..."

-- DaveHart - 16 Sep 2009

Do we need a table of ntpq and ntpdc directives and state which category they fall under?

-- HarlanStenn - 16 Sep 2009

ntp-dev-4.2.5p217 addresses these issues by disabling saveconfig by default unless there is a saveconfigdir configured in ntp.conf. Further, the following ntp.conf knobs are rejected from remote configuration:

enable stats
filegen (except filegen ... enable and disable)

-- DaveHart - 20 Sep 2009

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