To make sure that a server learns if its IP has changed, the server
sometimes launches authority.z descriptor fetches from
update_router_descriptor_downloads. That's nice, but we're moving
towards a situation where update_router_descriptor_downloads doesn't
always get called. So this patch breaks the authority.z
check-and-fetch into a new function.
This function also renames last_routerdesc_download to a more
appropriate last_descriptor_download, and adds a new
update_all_descriptor_downloads() function.
(For now, this is unnecessary, since servers don't actually use
microdescriptors. But that could change, or bridges could start
using microdescriptors, and then we'll be glad this is refactored
nicely.)
To turn this on, set UseMicrodescriptors to "1" (or "auto" if you
want it on-if-you're-a-client). It should go auto-by-default once
0.2.3.1-alpha is released.
Because of our node logic, directory caches will never use
microdescriptors when they have the right routerinfo available.
Previously we ensured that it would get called periodically by doing
it from inside the code that added microdescriptors. That won't work
though: it would interfere with our code that tried to read microdescs
from disk initially. Instead, we should consider rebuilding the cache
periodically, and on startup.
Previously on 0.2.2, we'd never clean the cache. Now that we can
clean it, we want to add a condition to rebuild it: that should happen
whenever we have dropped enough microdescriptors that we could save a
lot of space.
No changes file, since 0.2.3 doesn't need one and 0.2.2 already has some
changes files for the backport of the microdesc_clean_cahce() function.
n_supported[i] has a random value prior to initialization, so a node
that doesn't have routerinfo available can have a random priority.
Patch contributed by wanoskarnet from #tor. Thanks!
Previously it would erroneously return true if ListenAddr was set for
a client port, even if that port itself was 0. This would give false
positives, which were not previously harmful... but which were about
to become.
A v0 HS authority stores v0 HS descriptors in the same descriptor
cache that its HS client functionality uses. Thus, if the HS
authority operator clears its client HS descriptor cache, ALL v0
HS descriptors will be lost. That would be bad.
These functions can return NULL for otherwise-valid values of
time_t. Notably, the glibc gmtime manpage says it can return NULL
if the year if greater than INT_MAX, and the windows MSDN gmtime
page says it can return NULL for negative time_t values.
Also, our formatting code is not guaranteed to correctly handle
years after 9999 CE.
This patch tries to correct this by detecting NULL values from
gmtime/localtime_r, and trying to clip them to a reasonable end of
the scale. If they are in the middle of the scale, we call it a
downright error.
Arguably, it's a bug to get out-of-bounds dates like this to begin
with. But we've had bugs of this kind in the past, and warning when
we see a bug is much kinder than doing a NULL-pointer dereference.
Boboper found this one too.
