1 // 2 // Copyright (C) 2022 The Android Open Source Project 3 // 4 // Licensed under the Apache License, Version 2.0 (the "License"); 5 // you may not use this file except in compliance with the License. 6 // You may obtain a copy of the License at 7 // 8 // http://www.apache.org/licenses/LICENSE-2.0 9 // 10 // Unless required by applicable law or agreed to in writing, software 11 // distributed under the License is distributed on an "AS IS" BASIS, 12 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 // See the License for the specific language governing permissions and 14 // limitations under the License. 15 16 //! Monotonic clock implementation. 17 18 use kmr_common::crypto; 19 20 /// Monotonic clock. 21 pub struct StdClock; 22 23 impl StdClock { 24 /// Create new clock instance, holding time since construction. new() -> Self25 pub fn new() -> Self { 26 Self {} 27 } 28 } 29 30 impl crypto::MonotonicClock for StdClock { now(&self) -> crypto::MillisecondsSinceEpoch31 fn now(&self) -> crypto::MillisecondsSinceEpoch { 32 let mut time = libc::timespec { tv_sec: 0, tv_nsec: 0 }; 33 // Use `CLOCK_BOOTTIME` for consistency with the times used by the Cuttlefish 34 // C++ implementation of Gatekeeper. 35 let rc = 36 // Safety: `time` is a valid structure. 37 unsafe { libc::clock_gettime(libc::CLOCK_BOOTTIME, &mut time as *mut libc::timespec) }; 38 if rc < 0 { 39 log::warn!("failed to get time!"); 40 return crypto::MillisecondsSinceEpoch(0); 41 } 42 crypto::MillisecondsSinceEpoch(((time.tv_sec * 1000) + (time.tv_nsec / 1000 / 1000)).into()) 43 } 44 } 45