With the latest change on how we use the HSDir index, the client and service
need to pick their responsible HSDir differently that is depending on if they
are before or after a new time period.
The overlap mode is active function has been renamed for this and test added.
Signed-off-by: David Goulet <dgoulet@torproject.org>
Because of #23387, we've realized that there is one scenario that makes
the client unable to reach the service because of a desynch in the time
period used. The scenario is as follows:
+------------------------------------------------------------------+
| |
| 00:00 12:00 00:00 12:00 00:00 12:00 |
| SRV#1 TP#1 SRV#2 TP#2 SRV#3 TP#3 |
| |
| $==========|-----------$===========|-----------$===========| |
| ^ ^ |
| C S |
+------------------------------------------------------------------+
In this scenario the HS has a newer consensus than the client, and the
HS just moved to the next TP but the client is still stuck on the old
one. However, the service is not in any sort of overlap mode so it
doesn't cover the old TP anymore, so the client is unable to fetch a
descriptor.
We've decided to solve this by extending the concept of overlap period
to be permanent so that the service always publishes two descriptors and
aims to cover clients with both older and newer consensuses. See the
spec patch in #23387 for more details.
Based on our #23387 findings, it seems like to maintain 24/7
reachability we need to employ different logic when computing hsdir
indices for fetching vs storing. That's to guarantee that the client
will always fetch the current descriptor, while the service will always
publish two descriptors aiming to cover all possible edge cases.
For more details see the next commit and the spec branch.
Signed-off-by: David Goulet <dgoulet@torproject.org>
Use the valid_after time from the consensus to get the time period number else
we might get out of sync with the overlap period that uses valid_after.
Make it an optional feature since some functions require passing a
specific time (like hs_get_start_time_of_next_time_period()).
Signed-off-by: David Goulet <dgoulet@torproject.org>
Version 3 hidden service needs rendezvous point that have the protocol version
HSRend >= 2 else the rendezvous cells are rejected.
Fixes#23361
Signed-off-by: David Goulet <dgoulet@torproject.org>
There are two reasons this is likeliest to happen -- no kernel
support, and some bug in Tor. We'll ask people to check the former
before they report. Closes 23090.
I'm doing this using the Proxy-Authorization: header to support
clients that understand it, and with a new tor-specific header that
makes more sense for our use.
By convention, a function that frobs a foo_t should be called
foo_frob, and it should have a foo_t * as its first argument. But
for many of the buf_t functions, the buf_t was the final argument,
which is silly.
Our convention is that functions which manipulate a type T should be
named T_foo. But the buffer functions were super old, and followed
all kinds of conventions. Now they're uniform.
Here's the perl I used to do this:
\#!/usr/bin/perl -w -i -p
s/read_to_buf\(/buf_read_from_socket\(/;
s/flush_buf\(/buf_flush_to_socket\(/;
s/read_to_buf_tls\(/buf_read_from_tls\(/;
s/flush_buf_tls\(/buf_flush_to_tls\(/;
s/write_to_buf\(/buf_add\(/;
s/write_to_buf_compress\(/buf_add_compress\(/;
s/move_buf_to_buf\(/buf_move_to_buf\(/;
s/peek_from_buf\(/buf_peek\(/;
s/fetch_from_buf\(/buf_get_bytes\(/;
s/fetch_from_buf_line\(/buf_get_line\(/;
s/fetch_from_buf_line\(/buf_get_line\(/;
s/buf_remove_from_front\(/buf_drain\(/;
s/peek_buf_startswith\(/buf_peek_startswith\(/;
s/assert_buf_ok\(/buf_assert_ok\(/;
This lets us drop the testing-only function buf_get_first_chunk_data(),
and lets us implement proto_http and proto_socks without looking at
buf_t internals.
The service needs the latest SRV and set of relays for the best accurate
hashring to upload its descriptor to so it needs a live consensus thus don't
do anything until we have it.
Fixes#23331
Signed-off-by: David Goulet <dgoulet@torproject.org>
When merging #20657, somehow hs_service_dir_info_changed() became unused
leading to not use the re-upload to HSDir when we were missing information
feature.
Turns out that it is not possible to pick an HSDir with a missing descriptor
because in order to compute the HSDir index, the descriptor is mandatory to
have so we can know its position on the hashring.
This commit removes that dead feature and fix the
hs_service_dir_info_changed() not being used.
Signed-off-by: David Goulet <dgoulet@torproject.org>
Based on questions and comments from dgoulet, I've tried to fill
in the reasoning about why these functions work in the way that they
do, so that it will be easier for future programmers to understand
why this code exists and works the way it does.
We used to check if it was set to 0 which is what unused circuit have but when
the rendezvous circuit was cannibalized, the timestamp_dirty is not 0 but we
still need to reset it so we can actually use it without having the chance of
expiring the next second (or very soon).
Fixes#23123
Signed-off-by: David Goulet <dgoulet@torproject.org>
The function was never returning an error code on failure to parse the
OutboundAddress* options.
In the process, it was making our test_options_validate__outbound_addresses()
not test the right thing.
Fixes#23366
Signed-off-by: David Goulet <dgoulet@torproject.org>
This fixes a serious bug in our hsdir set change logic:
We used to add nodes in the list of previous hsdirs everytime we
uploaded to a new hsdir and we only cleared the list when we built a new
descriptor. This means that our prev_hsdirs list could end up with 7
hsdirs, if for some reason we ended up uploading our desc to 7 hsdirs
before rebuilding our descriptor (e.g. this can happen if the set of
hsdirs changed).
After our previous hdsir set had 7 nodes, then our old algorithm would
always think that the set has changed since it was comparing a smartlist
with 7 elements against a smartlist with 6 elements.
This commit fixes this bug, by clearning the prev_hsdirs list before we
upload to all hsdirs. This makes sure that our prev_hsdirs list always
contains the latest hsdirs!
Our logic for detecting hsdir set changes was needlessly compicated: we
had to sort smartlists and compare them.
Instead, we can simplify things by employing the following logic:
"We should reupload our descriptor if the latest HSDir set contains
nodes that were not previously there"
