Previously the client would ask the bridge for microdescriptors, which are
only supported in 0.2.3.x and later, and then fail to bootstrap when it
didn't get the answers it wanted. Fixes bug 4013; bugfix on 0.2.3.2-alpha.
The fix here is to revert to using normal descriptors if any of our
bridges are known to not support microdescs. This is not ideal, a) because
we'll start downloading a microdesc consensus as soon as we get a bridge
descriptor, and that will waste time if we later get a bridge descriptor
that tells us we don't like microdescriptors; and b) by changing our mind
we're leaking to our other bridges that we have an old-version bridge.
The alternate fix would have been to change
we_use_microdescriptors_for_circuits() to ask if *any* of our bridges
can support microdescriptors, and then change the directory logic that
picks a bridge to only select from those that do. For people living in
the future, where 0.2.2.x is obsolete, there won't be a difference.
Note that in either of these potential fixes, we have risk of oscillation
if our one funny-looking bridges goes away / comes back.
Previously, if you were set up to use microdescriptors, and you
weren't a cache, you'd never fetch router descriptors (except for
bridges). Now FetchUselessDescriptors causes descriptors and
mirodescs to get cached. Also, FetchUselessDescriptors changes the
behavior of "UseMicrodescriptors auto" to be off, since there's no
point in saying "UseMicrodescriptors 1" when you have full descriptors
too.
Fix for bug 3851; bugfix on 0.2.3.1-alpha.
It turns out that it wasn't enough to set the configuration to
"auto", since the correct behavior for "auto" had been disabled in
microdesc.c. :p
(Hasn't been in a release yet, so doesn't need a changes entry.)
This lets us make a lot of other stuff const, allows the compiler to
generate (slightly) better code, and will make me get slightly fewer
patches from folks who stick mutable stuff into or_options_t.
const: because not every input is an output!
On IRC, wanoskarnet notes that if we ever do microdesc_free() on a
microdesc that's in the nodelist, we're in trouble. Also, we're in
trouble if we free one that's still in the microdesc_cache map.
This code adds a flag to microdesc_t to note where the microdesc is
referenced from, and checks those flags from microdesc_free(). I
don't believe we have any errors here now, but if we introduce some
later, let's log and recover from them rather than introducing
heisenbugs later on.
Addresses bug 3153.
Conflicts in various places, mainly node-related. Resolved them in
favor of HEAD, with copying of tor_mem* operations from bug3122_memcmp_022.
src/common/Makefile.am
src/or/circuitlist.c
src/or/connection_edge.c
src/or/directory.c
src/or/microdesc.c
src/or/networkstatus.c
src/or/router.c
src/or/routerlist.c
src/test/test_util.c
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.
A node_t is an abstraction over routerstatus_t, routerinfo_t, and
microdesc_t. It should try to present a consistent interface to all
of them. There should be a node_t for a server whenever there is
* A routerinfo_t for it in the routerlist
* A routerstatus_t in the current_consensus.
(note that a microdesc_t alone isn't enough to make a node_t exist,
since microdescriptors aren't usable on their own.)
There are three ways to get a node_t right now: looking it up by ID,
looking it up by nickname, and iterating over the whole list of
microdescriptors.
All (or nearly all) functions that are supposed to return "a router"
-- especially those used in building connections and circuits --
should return a node_t, not a routerinfo_t or a routerstatus_t.
A node_t should hold all the *mutable* flags about a node. This
patch moves the is_foo flags from routerinfo_t into node_t. The
flags in routerstatus_t remain, but they get set from the consensus
and should not change.
Some other highlights of this patch are:
* Looking up routerinfo and routerstatus by nickname is now
unified and based on the "look up a node by nickname" function.
This tries to look only at the values from current consensus,
and not get confused by the routerinfo_t->is_named flag, which
could get set for other weird reasons. This changes the
behavior of how authorities (when acting as clients) deal with
nodes that have been listed by nickname.
* I tried not to artificially increase the size of the diff here
by moving functions around. As a result, some functions that
now operate on nodes are now in the wrong file -- they should
get moved to nodelist.c once this refactoring settles down.
This moving should happen as part of a patch that moves
functions AND NOTHING ELSE.
* Some old code is now left around inside #if 0/1 blocks, and
should get removed once I've verified that I don't want it
sitting around to see how we used to do things.
There are still some unimplemented functions: these are flagged
with "UNIMPLEMENTED_NODELIST()." I'll work on filling in the
implementation here, piece by piece.
I wish this patch could have been smaller, but there did not seem to
be any piece of it that was independent from the rest. Moving flags
forces many functions that once returned routerinfo_t * to return
node_t *, which forces their friends to change, and so on.
The node_t type is meant to serve two key functions:
1) Abstracting difference between routerinfo_t and microdesc_t
so that clients can use microdesc_t instead of routerinfo_t.
2) Being a central place to hold mutable state about nodes
formerly held in routerstatus_t and routerinfo_t.
This patch implements a nodelist type that holds a node for every
router that we would consider using.
We accidentally freed the internal buffer for bridge stats when we
were writing the bridge stats file or honoring a control port
request for said data. Change the interfaces for
geoip_get_bridge_stats* to prevent these problems, and remove the
offending free/add a tor_strdup.
Fixes bug 1208.
