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secure parasitic rdate replacement
C Shell

Merge pull request #174 from d1b/switch_default_host_to_google

Switch from www.ptb.de which is sending a randomised time to google.com.
latest commit f01d27fc81
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ca-roots remove TÜRKTRUST from CA list post sub-ca mistakes
dbus CHROMIUM: Initial work eventizing tlsdated
etc Switch from www.ptb.de which is sending a randomised time to google.com.
init continued merge issues: platform, debug, configs
m4 Fix from Paul Wouters to build
man Switch from www.ptb.de which is sending a randomised time to google.com.
src Switch from www.ptb.de which is sending a randomised time to google.com.
systemd Update systemd file
tests continued merge overhaul
.gitignore Update .gitignore to reflect ctags/vim usage
.travis.yml Add libtool to .travis.yml
AUTHORS add wad to AUTHORS
CHANGELOG ready for 0.0.12 release
HACKING.md Lets integrate an image that shows build status
HARDENING Add note on current state of affairs for Windows in HARDENING
INSTALL add git-buildpackage to INSTALL
LICENSE first commit
Makefile.am Switch from www.ptb.de which is sending a randomised time to google.com.
Makefile.android android build scripts and instructions
README Update README to make it timeless, so to speak
TLSDATEPOOL Idea for genepool.tlsdate.net; pool.ntp.org eat your heart out
TODO remove TODO item
apparmor-profile allow the unprivileged helper to read the time
autogen.sh Start MinGW support
configure.ac bump to 0.0.12
events.dot CHROMIUM: Initial work eventizing tlsdated
mkfile initial plan9 build of tlsdate-helper-plan9.c, doesn't quite build an…
run-tests
test.conf Add integration testing.
tlsdate-brew-formula.rb Update brew forumla for tlsdate
tlsdate-seccomp-amd64.policy Add Seccomp-BPF policies to the repo.
tlsdate-seccomp-arm.policy Add Seccomp-BPF policies to the repo.
tlsdate-seccomp-x86.policy Add Seccomp-BPF policies to the repo.

README

tlsdate: secure parasitic rdate replacement

 tlsdate sets the local clock by securely connecting with TLS to remote
 servers and extracting the remote time out of the secure handshake. Unlike
 ntpdate, tlsdate uses TCP, for instance connecting to a remote HTTPS or TLS
 enabled service, and provides some protection against adversaries that try to
 feed you malicious time information.

On Debian GNU/Linux and related systems, we provide an init.d script that
controls the tlsdated daemon. It will notice network changes and regularly
invoke tlsdate to keep the clock in sync. Start it like so:

  /etc/init.d/tlsdate start


Here is an example an unprivileged user fetching the remote time:

  % tlsdate -V -n -H encrypted.google.com
  Fri Apr 19 17:56:46 PDT 2013


This is an example run - starting as root and dropping to nobody, setting the
clock and printing it:

  % sudo tlsdate -V
  Fri Apr 19 17:57:49 PDT 2013


Here is an example with a custom host and custom port without verification:

  % sudo tlsdate --skip-verification -p 80 -H rgnx.net

Here is an example where a system may not have any kind of RTC at boot. Do the
time warp to restore sanity and do so with a leap of faith:

  % sudo tlsdate -V -l -t
  Fri Apr 19 18:08:03 PDT 2013


Some SSL/TLS services do not provide accurate time in their handshake process;
tlsdate may also be used to fetch time by processing the HTTP Date headers of
HTTP services:

  % sudo tlsdate -V -l -t -w
  Wed Oct 30 18:08:46 CET 2013


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