mirror of https://github.com/authelia/authelia.git
49 lines
1.2 KiB
Go
49 lines
1.2 KiB
Go
package ntp
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import "time"
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// ntpLeapVersionClientMode does the mathematics to configure the leap/version/mode value of an NTP client packet.
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func ntpLeapVersionClientMode(version ntpVersion) (lvm uint8) {
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lvm = (lvm & maskMode) | uint8(modeClient)
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switch version {
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case ntpV3:
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lvm = (lvm & maskVersion) | uint8(version3)<<3
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case ntpV4:
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lvm = (lvm & maskVersion) | uint8(version4)<<3
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}
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lvm = (lvm & maskLeap) | uint8(leapUnknown)<<6
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return lvm
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}
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// ntpPacketToTime converts a NTP server response into a time.Time.
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func ntpPacketToTime(packet *ntpPacket) time.Time {
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seconds := float64(packet.TxTimeSeconds) - ntpEpochOffset
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nanoseconds := (int64(packet.TxTimeFraction) * 1e9) >> 32
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return time.Unix(int64(seconds), nanoseconds)
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}
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// ntpIsOffsetTooLarge return true if there is offset of "offset" between two times.
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func ntpIsOffsetTooLarge(maxOffset time.Duration, first, second time.Time) (tooLarge bool) {
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var offset time.Duration
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if first.After(second) {
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offset = first.Sub(second)
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} else {
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offset = second.Sub(first)
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}
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return offset > maxOffset
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}
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func calcOffset(first, second time.Time) time.Duration {
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if first.After(second) {
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return first.Sub(second)
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}
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return second.Sub(first)
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}
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