From 7e8ee5ed9cad6484e9f13f81731b102ced58402e Mon Sep 17 00:00:00 2001 From: Adam Carpenter Date: Tue, 9 Jul 2019 15:14:04 -0400 Subject: Init. --- meap/meap-code/ch9/ch9-clock3/Cargo.toml | 19 ++ meap/meap-code/ch9/ch9-clock3/Dockerfile | 10 + meap/meap-code/ch9/ch9-clock3/src/main.rs | 333 ++++++++++++++++++++++++++++++ 3 files changed, 362 insertions(+) create mode 100755 meap/meap-code/ch9/ch9-clock3/Cargo.toml create mode 100755 meap/meap-code/ch9/ch9-clock3/Dockerfile create mode 100755 meap/meap-code/ch9/ch9-clock3/src/main.rs (limited to 'meap/meap-code/ch9/ch9-clock3') diff --git a/meap/meap-code/ch9/ch9-clock3/Cargo.toml b/meap/meap-code/ch9/ch9-clock3/Cargo.toml new file mode 100755 index 0000000..c0cb2d9 --- /dev/null +++ b/meap/meap-code/ch9/ch9-clock3/Cargo.toml @@ -0,0 +1,19 @@ +[package] +name = "clock" +version = "0.1.3" +authors = ["Tim McNamara "] + +[dependencies] +byteorder = "1" +chrono = "0.4" +clap = "2.32" + +[target.'cfg(windows)'.dependencies] +winapi = "0.2" +kernel32-sys = "0.2" + +[target.'cfg(not(windows))'.dependencies] +libc = "0.2" + +[profile.release] +lto = true diff --git a/meap/meap-code/ch9/ch9-clock3/Dockerfile b/meap/meap-code/ch9/ch9-clock3/Dockerfile new file mode 100755 index 0000000..36055d0 --- /dev/null +++ b/meap/meap-code/ch9/ch9-clock3/Dockerfile @@ -0,0 +1,10 @@ +FROM rust:latest + +WORKDIR /opt/clock +COPY . . + +# docker run --rm --user "$(id -u)":"$(id -g)" -v "$PWD":/opt/clock -w /opt/clock rust:latest cargo build --release + +# RUN cargo build + +# CMD ["clock"] diff --git a/meap/meap-code/ch9/ch9-clock3/src/main.rs b/meap/meap-code/ch9/ch9-clock3/src/main.rs new file mode 100755 index 0000000..ad3ee9f --- /dev/null +++ b/meap/meap-code/ch9/ch9-clock3/src/main.rs @@ -0,0 +1,333 @@ +extern crate byteorder; +extern crate chrono; +extern crate clap; +#[cfg(not(windows))] extern crate libc; +#[cfg(windows)] extern crate kernel32; +#[cfg(windows)] extern crate winapi; + +use byteorder::{BigEndian, ReadBytesExt}; +use chrono::DateTime; +use chrono::Duration as ChronoDuration; +use chrono::{Datelike, TimeZone, Timelike}; +use chrono::{Local, Utc}; +use clap::{App, Arg}; +use std::mem::zeroed; +use std::net::UdpSocket; +use std::time::Duration; + +const NTP_MESSAGE_LENGTH: usize = 48; // 12*4 bytes +const NTP_TO_UNIX_SECONDS: i64 = 2_208_988_800; +const LOCAL_ADDR: &'static str = "0.0.0.0:12300"; + +#[derive(Default, Debug, Copy, Clone)] +struct NTPTimestamp { + seconds: u32, + fraction: u32, +} + +struct NTPMessage { + data: [u8; NTP_MESSAGE_LENGTH], +} + +#[derive(Debug)] +struct NTPResult { + t1: DateTime, + t2: DateTime, + t3: DateTime, + t4: DateTime, +} + +impl NTPResult { + fn offset(&self) -> i64 { + let duration = (self.t2 - self.t1) + (self.t3 - self.t4); + duration.num_milliseconds() / 2 + } + + fn delay(&self) -> i64 { + let duration = (self.t4 - self.t1) - (self.t3 - self.t2); + duration.num_milliseconds() + } +} + +impl From for DateTime { + fn from(ntp: NTPTimestamp) -> Self { + let secs = ntp.seconds as i64 - NTP_TO_UNIX_SECONDS; + let mut nanos = ntp.fraction as f64; + nanos *= 1e9; + nanos /= 2_f64.powi(32); + + Utc.timestamp(secs, nanos as u32) + } +} + +impl From> for NTPTimestamp { + fn from(utc: DateTime) -> Self { + let secs = utc.timestamp() + NTP_TO_UNIX_SECONDS; + let mut fraction = utc.nanosecond() as f64; + fraction *= 2_f64.powi(32); + fraction /= 1e9; + + NTPTimestamp { + seconds: secs as u32, + fraction: fraction as u32, + } + } +} + +impl NTPMessage { + fn new() -> Self { + NTPMessage { + data: [0; NTP_MESSAGE_LENGTH], + } + } + + fn client() -> Self { + const VERSION: u8 = 3; + const MODE: u8 = 3; + + let mut msg = NTPMessage::new(); + + // the first byte of every NTP message contains three fields, + // but we only need to set two of them + msg.data[0] |= VERSION << 3; + msg.data[0] |= MODE; + msg + } + + fn parse_timestamp(&self, i: usize) -> Result { + let mut reader = &self.data[i..i + 8]; + let seconds = reader.read_u32::()?; + let fraction = reader.read_u32::()?; + + Ok(NTPTimestamp { + seconds: seconds, + fraction: fraction, + }) + } + + fn rx_time(&self) -> Result { + self.parse_timestamp(32) + } + + fn tx_time(&self) -> Result { + self.parse_timestamp(40) + } +} + +fn weighted_mean(values: &[f64], weights: &[f64]) -> f64 { + let mut result = 0.0; + let mut sum_of_weights = 0.0; + + for (v, w) in values.iter().zip(weights) { + result += v * w; + sum_of_weights += w; + } + + result / sum_of_weights +} + +fn ntp_roundtrip(host: &str, port: u16) -> Result { + let destination = format!("{}:{}", host, port); + let timeout = Duration::from_secs(1); + + let request = NTPMessage::client(); + let mut response = NTPMessage::new(); + + let message = request.data; + + let udp = UdpSocket::bind(LOCAL_ADDR)?; + udp.connect(&destination).expect("unable to connect"); + + let t1 = Utc::now(); + udp.send(&message)?; + udp.set_read_timeout(Some(timeout))?; + udp.recv_from(&mut response.data)?; + let t4 = Utc::now(); + + let t2: DateTime = response.rx_time().unwrap().into(); + let t3: DateTime = response.tx_time().unwrap().into(); + + Ok(NTPResult { + t1: t1, + t2: t2, + t3: t3, + t4: t4, + }) +} + +fn check_time() -> Result { + const NTP_PORT: u16 = 123; + + let servers = [ + "time.nist.gov", + "time.apple.com", + "time.euro.apple.com", + "time.google.com", + "time2.google.com", + //"time.windows.com", + ]; + + let mut times = Vec::with_capacity(servers.len()); + + for &server in servers.iter() { + print!("{} =>", server); + + let calc = ntp_roundtrip(&server, NTP_PORT); + + match calc { + Ok(time) => { + println!(" {}ms away from local system time", time.offset()); + times.push(time); + } + Err(_) => println!(" ? [response took too long]"), + }; + } + + let mut offsets = Vec::with_capacity(servers.len()); + let mut offset_weights = Vec::with_capacity(servers.len()); + + for time in × { + let offset = time.offset() as f64; + let delay = time.delay() as f64; + + let weight = 1_000_000.0 / (delay * delay); // <3> + if weight.is_finite() { + offsets.push(offset); + offset_weights.push(weight); + } + } + + let avg_offset = weighted_mean(&offsets, &offset_weights); + + Ok(avg_offset) +} + +struct Clock; + +impl Clock { + fn get() -> DateTime { + Local::now() + } + + #[cfg(windows)] + fn set(t: DateTime) -> () { + use chrono::Weekday; + use kernel32::SetSystemTime; + use winapi::{SYSTEMTIME, WORD}; + + let t = t.with_timezone(&Local); + + let mut systime: SYSTEMTIME = unsafe { zeroed() }; + + let dow = match t.weekday() { + Weekday::Mon => 1, + Weekday::Tue => 2, + Weekday::Wed => 3, + Weekday::Thu => 4, + Weekday::Fri => 5, + Weekday::Sat => 6, + Weekday::Sun => 0, + }; + + let mut ns = t.nanosecond(); + let is_leap_second = ns > 1_000_000_000; + + if is_leap_second { + ns -= 1_000_000_000; + } + + systime.wYear = t.year() as WORD; + systime.wMonth = t.month() as WORD; + systime.wDayOfWeek = dow as WORD; + systime.wDay = t.day() as WORD; + systime.wHour = t.hour() as WORD; + systime.wMinute = t.minute() as WORD; + systime.wSecond = t.second() as WORD; + systime.wMilliseconds = (ns / 1_000_000) as WORD; + + let systime_ptr = &systime as *const SYSTEMTIME; // as *mut SYSTEMTIME; // convert to a pointer, then change its mutability + + unsafe { + SetSystemTime(systime_ptr); // giving a pointer to a value to something outside of Rust's control is unsafe + } + } + + #[cfg(not(windows))] + fn set(t: DateTime) -> () { + use libc::settimeofday; + use libc::{suseconds_t, time_t, timeval, timezone}; + + let t = t.with_timezone(&Local); // variable names indicate the data's progression + let mut u: timeval = unsafe { zeroed() }; // through the function + + u.tv_sec = t.timestamp() as time_t; + u.tv_usec = t.timestamp_subsec_micros() as suseconds_t; + + unsafe { + let mock_tz: *const timezone = std::ptr::null(); + settimeofday(&u as *const timeval, mock_tz); + } + } +} + +fn main() { + let app = App::new("clock") + .version("0.1.3") + .about("Gets and sets the time.") + .after_help("Note: UNIX timestamps are parsed as whole seconds since 1st January 1970 0:00:00 UTC. For more accuracy, use another format.") + .arg(Arg::with_name("action") + .takes_value(true) + .possible_values(&["get", "set", "check-ntp"]) + .default_value("get")) + .arg(Arg::with_name("std") + .short("s") + .long("use-standard") + .takes_value(true) + .possible_values(&["rfc2822", "rfc3339", "timestamp"]) + .default_value("rfc3339")) + .arg(Arg::with_name("datetime") + .help("When is 'set', apply . Otherwise, ignore.")); + + let args = app.get_matches(); + + let action = args.value_of("action").unwrap(); // default_value() has been supplied, + let std = args.value_of("std").unwrap(); // so it's safe to use .unwrap() + + if action == "set" { + let t_ = args.value_of("datetime").unwrap(); + + let parser = match std { + "rfc2822" => DateTime::parse_from_rfc2822, + "rfc3339" => DateTime::parse_from_rfc3339, + _ => unimplemented!(), + }; + + let err_msg = format!("Unable to parse {} according to {}", t_, std); + let t = parser(t_).expect(&err_msg); + + Clock::set(t); + } else if action == "check-ntp" { + let offset = check_time().unwrap() as isize; + let adjust_ms = offset.signum() * offset.abs().min(200) / 5; + let adjust_ms_ = ChronoDuration::milliseconds(adjust_ms as i64); + let now: DateTime = Utc::now() + adjust_ms_; + Clock::set(now); + } + + let maybe_error = std::io::Error::last_os_error(); + let os_error_code = &maybe_error.raw_os_error(); + match os_error_code { + Some(0) => (), + None => (), + _ => eprintln!("Unable to set the time: {:?}", maybe_error), + } + + let now = Clock::get(); + + match std { + "timestamp" => println!("{}", now.timestamp()), + "rfc2822" => println!("{}", now.to_rfc2822()), + "rfc3339" => println!("{}", now.to_rfc3339()), + _ => unreachable!(), + } +} -- cgit v1.2.3