Some PT applications support more than one transport. For example,
obfs4proxy supports obfs4, obfs3, and meek. If one or more transports
specified in the torrc file are supported, we shouldn't kill the managed
proxy on a {C,S}METHOD-ERROR. Instead, we should log a warning.
We were already logging warnings on method errors. This change just
makes sure that the managed proxy isn't killed, and then if no
transports are configured for the managed proxy, bumps the log level up
from a notice to a warning.
Closes#7362
When we don't yet have a descriptor for one of our bridges, disable
the entry guard retry schedule on that bridge. The entry guard retry
schedule and the bridge descriptor retry schedule can conflict,
e.g. where we mark a bridge as "maybe up" yet we don't try to fetch
its descriptor yet, leading Tor to wait (refusing to do anything)
until it becomes time to fetch the descriptor.
Fixes bug 40497; bugfix on 0.3.0.3-alpha.
Specifically, every time a guard moves into or out of state
GUARD_REACHABLE_MAYBE, it is an opportunity for the guard reachability
state to get out of sync with the have-minimum-dir-info state.
Fixes even more of #40396.
When we try to fetch a bridge descriptor and we fail, we mark
the guard as failed, but we never scheduled a re-compute for
router_have_minimum_dir_info().
So if we had already decided we needed to wait for this new descriptor,
we would just wait forever -- even if, counterintuitively, *losing* the
bridge is just what we need to *resume* using the network, if we had it
in state GUARD_REACHABLE_MAYBE and we were stalling to learn this outcome.
See bug 40396 for more details.
The bridge descriptor fetching codes ends up fetching a lot of duplicate
bridge descriptors, because this is how we learn when the descriptor
changes.
This commit only changes comments plus whether we log that one line.
It moves us back to the old behavior, before the previous commit for
30496, where we would only log that line when the bridge descriptor
we're talking about is better than the one we already had (if any).
Without this change, if we have a working bridge, and we add a new bridge,
we will schedule the fetch attempt for that new bridge descriptor for
three hours(!) in the future.
This change is especially needed because of bug #40396, where if you have
one working bridge and one bridge whose descriptor you haven't fetched
yet, your Tor will stall until you have successfully fetched that new
descriptor -- in this case for hours.
In the old design, we would put off all further bridge descriptor fetches
once we had any working bridge descriptor. In this new design, we make the
decision per bridge based on whether we successfully got *its* descriptor.
To make this work, we need to also call learned_bridge_descriptor() every
time we get a bridge descriptor, not just when it's a novel descriptor.
Fixes bug 40396.
Also happens to fix bug 40495 (redundant descriptor fetches for every
bridge) since now we delay fetches once we succeed.
A side effect of this change is that if we have any configured bridges
that *aren't* working, we will keep trying to fetch their descriptors
on the modern directory retry schedule -- every couple of seconds for
the first half minute, then backing off after that -- which is a lot
faster than before.
Values greater than 100 would have had the same effect as 100, so
this doesn't actually change Tor's behavior; it just makes the
intent clearer. Fixes#40486; see also torspec#66.
This is related to ticket #40360 which found this problem when a Bridge entry
with a transport name (let say obfs4) is set without a fingerprint:
Bridge obfs4 <IP>:<PORT> cert=<...> iat-mode=0
(Notice, no fingerprint between PORT and "cert=")
Problem: commit 09c6d03246 added a check in
get_sampled_guard_for_bridge() that would return NULL if the selected bridge
did not have a valid transport name (that is the Bridge transport name that
corresponds to a ClientTransportPlugin).
Unfortuantely, this function is also used when selecting our eligible guards
which is done *before* the transport list is populated and so the added check
for the bridge<->transport name is querying an empty list of transports
resulting in always returning NULL.
For completion, the logic is: Pick eligible guards (use bridge(s) if need be)
then for those, initiate a connection to the pluggable transport proxy and
then populate the transport list once we've connected.
Back to get_sampled_guard_for_bridge(). As said earlier, it is used when
selecting our eligible guards in a way that prevents us from selecting
duplicates. In other words, if that function returns non-NULL, the selection
continues considering the bridge was sampled before. But if it returns NULL,
the relay is added to the eligible list.
This bug made it that our eligible guard list was populated with the *same*
bridge 3 times like so (remember no fingerprint):
[info] entry_guards_update_primary(): Primary entry guards have changed. New primary guard list is:
[info] entry_guards_update_primary(): 1/3: [bridge] ($0000000000000000000000000000000000000000)
[info] entry_guards_update_primary(): 2/3: [bridge] ($0000000000000000000000000000000000000000)
[info] entry_guards_update_primary(): 3/3: [bridge] ($0000000000000000000000000000000000000000)
When tor starts, it will find the bridge fingerprint by connecting to it and
will then update the primary guard list by calling
entry_guard_learned_bridge_identity() which then goes and update only 1 single
entry resulting in this list:
[debug] sampled_guards_update_consensus_presence(): Sampled guard [bridge] ($<FINGERPRINT>) is still listed.
[debug] sampled_guards_update_consensus_presence(): Sampled guard [bridge] ($0000000000000000000000000000000000000000) is still listed.
[debug] sampled_guards_update_consensus_presence(): Sampled guard [bridge] ($0000000000000000000000000000000000000000) is still listed.
And here lies the problem, now tor is stuck attempting to wait for a valid
descriptor for at least 2 guards where the second one is a bunch of zeroes and
thus tor will never fully bootstraps:
[info] I learned some more directory information, but not enough to build a
circuit: We're missing descriptors for 1/2 of our primary entry guards
(total microdescriptors: 6671/6703). That's ok. We will try to fetch missing
descriptors soon.
Now, why passing the fingerprint then works? This is because the list of
guards contains 3 times the same bridge but they all have a fingerprint and so
the descriptor can be found and tor can bootstraps.
The solution here is to entirely remove the transport name check in
get_sampled_guard_for_bridge() since the transport_list is empty at that
point. That way, the eligible guard list only gets 1 entry, the bridge, and
can then go on to bootstrap properly.
It is OK to do so since when launching a bridge descriptor fetch, we validate
that the bridge transport name is OK and thus avoid connecting to a bridge
without a ClientTransportPlugin. If we wanted to keep the check in place, we
would need to populate the transport_list much earlier and this would require
a much bigger refactoring.
Fixes#40360
Signed-off-by: David Goulet <dgoulet@torproject.org>
Don't pick the bridge as the guard or launch descriptor fetch if no transport
is found.
Fixes#40106
Signed-off-by: David Goulet <dgoulet@torproject.org>
This one should work on GCC _and_ on Clang. The previous version
made Clang happier by not having unreachable "fallthrough"
statements, but made GCC sad because GCC didn't think that the
unconditional failures were really unconditional, and therefore
_wanted_ a FALLTHROUGH.
This patch adds a FALLTHROUGH_UNLESS_ALL_BUGS_ARE_FATAL macro that
seems to please both GCC and Clang in this case: ordinarily it is a
FALLTHROUGH, but when ALL_BUGS_ARE_FATAL is defined, it's an
abort().
Fixes bug 40241 again. Bugfix on earlier fix for 40241, which was
merged into maint-0.3.5 and forward, and released in 0.4.5.3-rc.
We're getting "fallback annotation annotation in unreachable code"
warnings when we build with ALL_BUGS_ARE_FATAL. This patch fixes
that.
Fixes bug 40241. Bugfix on 0.3.5.4-alpha.
When making sure we have a Bridge line with a ClientTransportPlugin, we
now check in the managed proxy list and so we can catch any missing
ClientTransportPlugin for a Bridge line.
Fixes#40106
Signed-off-by: David Goulet <dgoulet@torproject.org>
Typos found with codespell.
Please keep in mind that this should have impact on actual code
and must be carefully evaluated:
src/core/or/lttng_circuit.inc
- ctf_enum_value("CONTROLER", CIRCUIT_PURPOSE_CONTROLLER)
+ ctf_enum_value("CONTROLLER", CIRCUIT_PURPOSE_CONTROLLER)
This patch adds support for exposing the environment variables
`TOR_PT_OUTBOUND_BIND_ADDRESS_V4` and `TOR_PT_OUTBOUND_BIND_ADDRESS_V6` to
Pluggable Transport proccesses. These two values will contain the IPv4
and IPv6 address that the user have specified in torrc that they wish
the PT to use for all outgoing IP packets.
It is important to note here that it is up to the indvidual Pluggable
Transport if they are willing to honor these values or ignore them
completely.
One can test this feature using the following dummy PT written in POSIX
shell script:
#!/bin/sh
echo "LOG SEVERITY=warning MESSAGE=\"Value for IPv4: ${TOR_PT_OUTBOUND_BIND_ADDRESS_V4}\""
echo "LOG SEVERITY=warning MESSAGE=\"Value for IPv6: ${TOR_PT_OUTBOUND_BIND_ADDRESS_V6}\""
while true ; do
sleep 1
done
with the following entries in your torrc:
OutboundBindAddressPT 203.0.113.4
OutboundBindAddress 203.0.113.5
OutboundBindAddressPT 2001:db8::4
OutboundBindAddress 2001:db8::5
See: https://bugs.torproject.org/5304
We used to have a single boolean, "FascistFirewall". Ages ago, in
tickets #17840 and #9067, we added an improved "ReachableAddresses"
mechanism. It's time to rename related identifiers in the code for
consistency. This closes#18106.
This is an automated commit, generated by this command:
./scripts/maint/rename_c_identifier.py \
fascist_firewall_allows_address reachable_addr_allows \
fascist_firewall_use_ipv6 reachable_addr_use_ipv6 \
fascist_firewall_prefer_ipv6_impl reachable_addr_prefer_ipv6_impl \
fascist_firewall_prefer_ipv6_orport reachable_addr_prefer_ipv6_orport \
fascist_firewall_prefer_ipv6_dirport reachable_addr_prefer_ipv6_dirport \
fascist_firewall_allows_address_addr reachable_addr_allows_addr \
fascist_firewall_allows_address_ap reachable_addr_allows_ap \
fascist_firewall_allows_base reachable_addr_allows_base \
fascist_firewall_allows_ri_impl reachable_addr_allows_ri_impl \
fascist_firewall_allows_rs_impl reachable_addr_allows_rs_impl \
fascist_firewall_allows_rs reachable_addr_allows_rs \
fascist_firewall_allows_md_impl reachable_addr_allows_md_impl \
fascist_firewall_allows_node reachable_addr_allows_node \
fascist_firewall_allows_dir_server reachable_addr_allows_dir_server \
fascist_firewall_choose_address_impl reachable_addr_choose_impl \
fascist_firewall_choose_address reachable_addr_choose \
fascist_firewall_choose_address_base reachable_addr_choose_base \
fascist_firewall_choose_address_rs reachable_addr_choose_from_rs \
fascist_firewall_choose_address_ls reachable_addr_choose_from_ls \
fascist_firewall_choose_address_node reachable_addr_choose_from_node \
fascist_firewall_choose_address_dir_server reachable_addr_choose_from_dir_server
Instead of a boolean saying "cache_only" add the concept of flags so we add
semantic through out the code and allow ourselves to have more options in the
future.
Signed-off-by: David Goulet <dgoulet@torproject.org>
Previous development introduced the error of using 0/1 for a boolean
parameter. Fix that everywhere
Related #40025
Signed-off-by: David Goulet <dgoulet@torproject.org>
In case the transport has no usable address configured (likely 0.0.0.0 or
[::]), attempt to find the IPv4 and on failure, fallback to the IPv6. If none
are found, a log error is emitted and the transport is skiped.
Related to #40025
Signed-off-by: David Goulet <dgoulet@torproject.org>
This changes a LOT of code but in the end, behavior is the same.
Unfortunately, many functions had to be changed to accomodate but in majority
of cases, to become simpler.
Functions are also removed specifically those that were there to convert an
IPv4 as a host format to a tor_addr_t. Those are not needed anymore.
The IPv4 address field has been standardized to "ipv4_addr", the ORPort to
"ipv4_orport" (currently IPv6 uses ipv6_orport) and DirPort to "ipv4_dirport".
This is related to Sponsor 55 work that adds IPv6 support for relays and this
work is needed in order to have a common interface between IPv4 and IPv6.
Closes#40043.
Signed-off-by: David Goulet <dgoulet@torproject.org>
Hans-Christoph Steiner
Alexander Færøy
Cecylia Bocovich
Nick Mathewson
Roger Dingledine
George Kadianakis
David Goulet
Neel Chauhan
Samanta Navarro