Implements proposal 215; closes ticket 10163.
Why? From proposal 215:
Consensus method 1 is no longer viable for the Tor network. It
doesn't result in a microdescriptor consensus, and omits other
fields that clients need in order to work well. Consensus methods
under 12 have security issues, since they let a single authority
set a consensus parameter.
...
For example, while Tor 0.2.4.x is under development, authorities
should really not be running anything before Tor 0.2.3.x. Tor
0.2.3.x has supported consensus method 13 since 0.2.3.21-rc, so
it's okay for 0.2.4.x to require 13 as the minimum method. We even
might go back to method 12, since the worst outcome of not using 13
would be some warnings in client logs. Consensus method 12 was a
security improvement, so we don't want to roll back before that.
When we merged the cookieauthfile creation logic in 33c3e60a37, we
accidentally took out this feature. Fixes bug 12864, bugfix on
0.2.5.1-alpha.
Also adds an ExtORPortCookieAuthFileGroupReadable, since there's no
reason not to.
Coccinelle is a semantic patching tool that can automatically change
C code via semantic patching.
This script also replaces realloc with reallocarray as appropriate.
I looked for other places where we set circ->n_chan early, and found
one in circuit_handle_first_hop() right before it calls
circuit_send_next_onion_skin(). If onion_skin_create() fails there,
then n_chan will still be set when circuit_send_next_onion_skin()
returns. We should probably fix that too.
When Tor starts with DisabledNetwork set, it would correctly
conclude that it shouldn't try making circuits, but it would
mistakenly cache this conclusion and continue believing it even
when DisableNetwork is set to 0. Fixes the bug introduced by the
fix for bug 11200; bugfix on 0.2.5.4-alpha.
Our current systemd unit uses "Type = simple", so systemd does not expect tor to
fork. If the user has "RunAsDaemon 1" in their torrc, then things won't work as
expected. This is e.g. the case on Debian (and derivatives), since there we pass
"--defaults-torrc /usr/share/tor/tor-service-defaults-torrc" (that contains
"RunAsDaemon 1") by default.
The only solution I could find is to explicitly pass "--RunAsDaemon 0" when
starting tor from the systemd unit file, which this commit does.
