According to POSIX, the mutex must be locked by the thread calling the signal
functions to ensure predictable scheduling behavior.
Found the issue using Helgrind which gave the warning `dubious: associated lock
is not held by any thread`.
The control port was using set_max_file_descriptors() with a limit set to 0
to query the number of maximum socket Tor can use. With the recent changes
to that function, a check was introduced to make sure a user can not set a
value below the amount we reserved for non socket.
This commit adds get_max_sockets() that returns the value of max_sockets so
we can stop using that "setter" function to get the current value.
Finally, the dead code is removed that is the code that checked for limit
equal to 0. From now on, set_max_file_descriptors() should never be used
with a limit set to 0 for a valid use case.
Fixes#16697
Signed-off-by: David Goulet <dgoulet@ev0ke.net>
URI syntax (and DNS syntax) allows for a single trailing `.` to
explicitly distinguish between a relative and absolute
(fully-qualified) domain name. While this is redundant in that RFC 1928
DOMAINNAME addresses are *always* fully-qualified, certain clients
blindly pass the trailing `.` along in the request.
Fixes bug 16674; bugfix on 0.2.6.2-alpha.
1) We already require C99.
2) This allows us to support MSVC again (thanks to Gisle Vanem for
this part)
3) This change allows us to dump some rotten old compatibility code
from log.c
It did a good idea, but the code-quality of libupnpc and libnatpnp
is so dodgy that I'm not really comfortable including them alongside
Tor proper. Instead, we'll recommend that people do the pure-go
reimplementation instead. Closes ticket 13338.
The runtime sanity checking is slightly different from the optimized
basepoint stuff in that it uses a given implementation's self tests if
available, and checks if signing/verification works with a test vector
from the IETF EdDSA draft.
The unit tests include a new testcase that will fuzz donna against ref0,
including the blinding and curve25519 key conversion routines. If this
is something that should be done at runtime (No?), the code can be
stolen from there.
Note: Integrating batch verification is not done yet.
Integration work scavanged from nickm's `ticket8897_9663_v2` branch,
with minor modifications. Tor will still sanity check the output but
now also attempts to catch extreme breakage by spot checking the
optimized implementation vs known values from the NaCl documentation.
Implements feature 9663.
The following arguments change how chutney verifies the network:
--bytes n sends n bytes per test connection (10 KBytes)
--connections n makes n test connections per client (1)
--hs-multi-client 1 makes each client connect to each HS (0)
Requires the corresponding chutney performance testing changes.
Note: using --connections 7 or greater on a HS will trigger #15937.
Patch by "teor".
This is a way to specify the amount of introduction points an hidden service
can have. Maximum value is 10 and the default is 3.
Fixes#4862
Signed-off-by: David Goulet <dgoulet@ev0ke.net>
When we ran out of intro points for a hidden service (which could
happen on a newnym), we would change the connection's state back to
"waiting for hidden service descriptor." But this would make an
assertion fail if we went on to call circuit_get_open_circ_or_launch
again.
This fixes bug 16013; I believe the bug was introduced in
38be533c69, where we made it possible for
circuit_get_open_circ_or_launch() to change the connection's state.
RFC 952 is approximately 30 years old, and people are failing to comply,
by serving A records with '_' as part of the hostname. Since relaxing
the check is a QOL improvement for our userbase, relax the check to
allow such abominations as destinations, especially since there are
likely to be other similarly misconfigured domains out there.
When I fixed#11243, I made it so we would take the digest of a
descriptor before tokenizing it, so we could desist from download
attempts if parsing failed. But when I did that, I didn't remove an
assertion that the descriptor began with "onion-key". Usually, this
was enforced by "find_start_of_next_microdescriptor", but when
find_start_of_next_microdescriptor returned NULL, the assertion was
triggered.
Fixes bug 16400. Thanks to torkeln for reporting and
cypherpunks_backup for diagnosing and writing the first fix here.
If crypto_early_init fails, a typo in a return value from tor_init
means that tor_main continues running, rather than returning
an error value.
Fixes bug 16360; bugfix on d3fb846d8c in 0.2.5.2-alpha,
introduced when implementing #4900.
Patch by "teor".
This reverts commit 9407040c59.
Small fix, "e->received" had to be removed since that variable doesn't exist
anymore.
Signed-off-by: David Goulet <dgoulet@ev0ke.net>
Document use of coverity, clang static analyzer, and clang dynamic
undefined behavior and address sanitizers in doc/HACKING.
Add clang dynamic sanitizer blacklist in
contrib/clang/sanitizer_blacklist.txt to exempt known undefined
behavior. Include detailed usage instructions in this blacklist file.
Patch by "teor".
signing_key can be NULL in ed_key_init_from_file in routerkeys.c.
Discovered by clang 3.7 address sanitizer.
Fix on c03694938e, not in any released version of Tor.
clang 3.7 complains that using a preprocessor directive inside
a macro invocation in test_util_writepid in test_util.c is undefined.
Fix on 79e85313aa on 0.2.7.1-alpha.
Unused variable warnings were still generated under some versions of OpenSSL.
Instead, make sure all variables are used under all versions.
Fix on 496df21c89, not in any released version of tor.
Rend_add_service() frees its argument on failure; no need to free again.
Fixes bug 16228, bugfix on 0.2.7.1-alpha
Found by coverity; this is CID 1301387.
As OpenSSL >= 1.0.0 is now required, ECDHE is now mandatory. The group
has to be validated at runtime, because of RedHat lawyers (P224 support
is entirely missing in the OpenSSL RPM, but P256 is present and is the
default).
Resolves ticket #16140.
When set, this limits the maximum number of simultaneous streams per
rendezvous circuit on the server side of a HS, with further RELAY_BEGIN
cells being silently ignored.
This can be modified via "HiddenServiceMaxStreamsCloseCircuit", which
if set will cause offending rendezvous circuits to be torn down instead.
Addresses part of #16052.
Ephemeral services will be listed in rend_services_list at the end of
rend_config_services, so it must check whether directory is non-NULL
before comparing.
This crash happens when reloading config on a tor with mixed configured
and ephemeral services.
Fixes bug #16060. Bugfix on 0.2.7.1-alpha.
For FAILED and RECEIVED action of the HS_DESC event, we now sends back the
descriptor ID at the end like specified in the control-spec section 4.1.25.
Fixes#15881
Signed-off-by: David Goulet <dgoulet@ev0ke.net>
- Rewrite changes file.
- Avoid float comparison with == and use <= instead.
- Add teor's tor_llround(trunc(...)) back to silence clang warnings.
- Replace tt_assert() with tt_i64_op() and friends.
- Fix whitespace and a comment.
Consistently check for overflow in round_*_to_next_multiple_of.
Check all round_*_to_next_multiple_of functions with expected values.
Check all round_*_to_next_multiple_of functions with maximal values.
Related to HS stats in #13192.
Avoid division by zero.
Avoid taking the log of zero.
Silence clang type conversion warnings using round and trunc.
The existing values returned by the laplace functions do not change.
Add tests for laplace edge cases.
These changes pass the existing unit tests without modification.
Related to HS stats in #13192.
The length of auth_data from an INTRODUCE2 cell is checked when the
auth_type is recognized (1 or 2), but not for any other non-zero
auth_type. Later, auth_data is assumed to have at least
REND_DESC_COOKIE_LEN bytes, leading to a client-triggered out of bounds
read.
Fixed by checking auth_len before comparing the descriptor cookie
against known clients.
Fixes#15823; bugfix on 0.2.1.6-alpha.
"+HSPOST" and the related event changes allow the uploading of HS
descriptors via the control port, and more comprehensive event
monitoring of HS descriptor upload status.
Fixes#15850, part of #15801. Change file is added by this commit. The
original comment in the reverted commit is removed because right now we
*need* a DirPort until #15849 is implemented so no doubt nor confusion there
anymore.
This reverts commit 80bed1ac96.
Signed-off-by: David Goulet <dgoulet@ev0ke.net>
These commands allow for the creation and management of ephemeral
Onion ("Hidden") services that are either bound to the lifetime of
the originating control connection, or optionally the lifetime of
the tor instance.
Implements #6411.
Unit tests for the 10 valid combinations of set/NULL config options
DirAuthorities, AlternateBridgeAuthority, AlternateDirAuthority,
and FallbackDir.
Add assertion in consider_adding_dir_servers() for checks in
validate_dir_servers():
"You cannot set both DirAuthority and Alternate*Authority."
Only add the default fallback directories when the DirAuthorities,
AlternateDirAuthority, and FallbackDir directory config options
are set to their defaults.
The default fallback directory list is currently empty, this fix will
only change tor's behaviour when it has default fallback directories.
Fixes bug 15642; bugfix on 90f6071d8d in 0.2.4.7-alpha. Patch by "teor".
When self-testing reachability, use ExtendAllowPrivateAddresses
to determine if local/private addresses imply reachability.
The previous fix used TestingTorNetwork, which implies
ExtendAllowPrivateAddresses, but this excluded rare configs where
ExtendAllowPrivateAddresses is set but TestingTorNetwork is not.
Fixes bug 15771; bugfix on 0.2.6.1-alpha, bug #13924.
Patch by "teor", issue discovered by CJ Ess.
An introduction point is currently rotated when the amount of INTRODUCE2
cells reached a fixed value of 16384. This makes it pretty easy for an
attacker to inflate that number and observe when the IP rotates which leaks
the popularity of the HS (amount of client that passed through the IP).
This commit makes it a random count between the current value of 16384 and
two times that.
Fixes#15745
Signed-off-by: David Goulet <dgoulet@ev0ke.net>
This uses a Linux-ism to attempt to always clean up background processes
if possible. Note that it is not a catch-all, in that executables with
suid/sgid or elevated capabilities will have the prctl() attribute
stripped as part of the execve().
Resolves ticket 15471.
Background processes spawned by Tor now will have a valid stdin.
Pluggable transports can detect this behavior with the aformentioned
enviornment variable, and exit if stdin ever gets closed.
The compiler is allowed to assume that a "uint64_t *" is aligned
correctly, and will inline a version of memcpy that acts as such.
Use "uint8_t *", so the compiler does the right thing.
It invokes undefined behavior, I'm afraid, since there's no other
c-legal way to test whether memwipe() works when we're not allowed to
look at it.
Closes ticket 15377.
On clang (and elsewhere?) __PRETTY_FUNCTION__ includes parenthesized
argument lists. This is clever, but it makes our old "%s(): " format
look funny.
This is a fix on 0957ffeb, aka svn:r288. Fixes bug 15269.
PTs expect the auth cookie to be available immedieately after launch,
leading to a race condition when PTs opt to cache the extorport cookie
once immediately after startup.
Fixes#15240.
When calling pthread_attr_setdetachstate, we were using 1 as the
argument. But the pthreads documentation says that you have to say
PTHREAD_CREATE_DETACH, which on Solaris is apparently 0x40. Calling
pthread_attr_setdetachstate with 1 crashes on Solaris with FLTBOUNDS.
(Because we're so late in the release cycle, I made the code define
PTHREAD_CREATE_DETACHED if it doesn't exist, so we aren't likely to
break any other platforms.)
This bug was introduced when we made threading mandatory in
0.2.6.1-alpha; previously, we had force-disabled threading on
Solaris. See #9495 discussion.
Additional fixes to make the change work;
- fix Python 2 vs 3 issues
- fix some PEP 8 warnings
- handle paths with numbers correctly
- mention the make rule in doc/HACKING.
`dir_info_status` is used from main.c:directory_info_has_arrived() to
provide useful (INFO/NOTICE) level logging to users, and should always
be updated regardless of the rate limiting.
The idea here is that a controller should be able to make Tor produce a
new relay descriptor on demand, without that descriptor actually being
uploaded to the dirauths (they would likely reject it anyway due to
freshness concerns).
Implements #14784.
__libc_message() tries to open /dev/tty with O_RDWR, but the sandbox
catches that and calls it a crash. Instead, I'm making the sandbox
setenv LIBC_FATAL_STDERR_, so that glibc uses stderr instead.
Fix for 14759, bugfix on 0.2.5.1-alpha
They have been off-by-default since 0.2.5 and nobody has complained. :)
Also remove the buf_shrink() function, which hasn't done anything
since we first stopped using contiguous memory to store buffers.
Closes ticket 14848.
like might happen for Tails or Whonix users who start with a very wrong
hardware clock, use Tor to discover a more accurate time, and then
fix their clock.
Resolves part of ticket 8766.
(There are still some timers in various places that aren't addressed yet.)
Before a couple weeks ago didn't know Tor had these tests, interesting! Stem
already has tests for spawning tor processes but lacked any with this targeted
focus on its arguments.
I've added our own counterpart for these tests. Many are direct copies but
there were others I improved a little...
https://trac.torproject.org/projects/tor/ticket/14109https://gitweb.torproject.org/stem.git/commit/?id=137d193a026638f066e817e3396cebbbb6ace012
Now that Tor uses Stem to supplement its tests no reason for these to live
separately. Tested by simply building tor and confirming test_cmdline_args.py
is no longer in the generated Makefile.
If the guard unreachable_since variable was set, the status "up" was
reported which is wrong. This adds the "down" status followed by the
unreachable_since time value.
Fixes#14184
Signed-off-by: David Goulet <dgoulet@ev0ke.net>
This both fixes the problem, and ensures that forgetting to update
domain_list in the future will trigger the bug codepath instead of
a NULL pointer deref.
After connectivity problems, only try connecting to bridges which
are currently configured; don't mark bridges which we previously
used but are no longer configured. Fixes 14216. Reported by
and fix provided by arma.
If the returned value of read/recv is 0 (meaning EOF), we'll end up in an
infinite loop (active wait) until something is written on the pipe which is
not really what we want here especially because those functions are called
from the main thread.
Signed-off-by: David Goulet <dgoulet@ev0ke.net>
Once a NACK is received on the intro circuit, tor tries an other usable one
by extending the current circuit to it. If no more intro points are usable,
now close the circuit. Also, it's reason is changed before closing it so we
don't report again an intro point failure and trigger an extra HS fetch.
Fixes#14224
Signed-off-by: David Goulet <dgoulet@ev0ke.net>
This fixes a bug where we'd fetch different replicas of the same
descriptor for a down hidden service over and over, until we got lucky
and fetched the same replica twice in a row.
Fixes bug 14219; bugfix on 0.2.0.10-alpha.
(Patch from Roger; commit message and changes file by Nick.)
We've started to hit the limit here. We introduced the limit in
0.1.2.5-alpha. This fixes bug 14261, but we should have a smarter way
to not actually do the behavior this permits. See #14267 for a ticket
about fixing that.
The trick here is to apply mapaddress first, and only then apply
automapping. Otherwise, the automap checks don't get done.
Fix for bug 7555; bugfix on all versions of Tor supporting both
MapAddress and AutoMap.
Check for a missing option value in parse_virtual_addr_network
before asserting on the NULL in tor_addr_parse_mask_ports.
This avoids crashing on torrc lines like Vi[rtualAddrNetworkIPv[4|6]]
when no value follows the option.
Bugfix on 0.2.3 (de4cc126cb on 24 November 2012), fixes#14142.
Drop the MIN_REND_INITIAL_POST_DELAY on a testing network to 5 seconds,
but keep the default at 30 seconds.
Reduces the hidden service bootstrap to 25 seconds from around 45 seconds.
Change the default src/test/test-network.sh delay to 25 seconds.
Closes ticket 13401.
TestingDirAuthVoteHSDir ensures that authorities vote the HSDir flag
for the listed relays regardless of uptime or ORPort connectivity.
Respects the value of VoteOnHidServDirectoriesV2.
Partial fix for bug 14067.
Check that tor generates new keys, and overwrites the empty key files.
Test that tor generates new keys when keys are missing (existing
behaviour).
Test that tor does not overwrite key files that already contain data
(existing behaviour).
Tests fixes to bug 13111.
Fixes bug 11454, where we would keep around a superseded descriptor
if the descriptor replacing it wasn't at least a week later. Bugfix
on 0.2.1.8-alpha.
Fixes bug 11457, where a certificate with a publication time in the
future could make us discard existing (and subsequent!) certificates
with correct publication times. Bugfix on 0.2.0.3-alpha.
Also, avoid crashing when we attempt to double-remove an edge
connection from the DNS resolver: just log a bug warning instead.
Fixes bug 14129. Bugfix on 0d20fee2fb, which was in 0.0.7rc1.
jowr found the bug. cypherpunks wrote the fix. I added the log
message and removed the assert.
"Maybe this time should be reduced, since we are considering
guard-related changes as quite important? It would be a pity to
settle on a guard node, then close the Tor client fast and lose that
information."
Closes 12485.
If we decide not to use a new guard because we want to retry older
guards, only close the locally-originating circuits passing through
that guard. Previously we would close all the circuits.
Fixes bug 9819; bugfix on 0.2.1.1-alpha. Reported by "skruffy".
Have clients and authorities both have new behavior, since the
fix for bug 11243 has gone in. But make clients still accept
accept old bogus HSDir descriptors, to avoid fingerprinting trickery.
Fixes bug 9286.
In systemd 209, they deprecated -lsystemd-daemon in favor of
-lsystemd. So we'd better actually look at the pkg-config output,
or we'll get warnings on newer distributions.
For some as-yet-unknown-to-me reason, setting CFLAGS so early makes
it so -O2 -g doesn't get added to it later. So, adding it myself
later. Perhaps a better fix here can be found.
Fixes 14072; bugfix on 0.2.6.2-alpha. Based on a patch from h.venev
We had a check to block these, but the patch we merged as a1c1fc72
broke this check by making them absolute on demand every time we
opened them. That's not so great though. Instead, we should make them
absolute on startup, and not let them change after that.
Fixes bug 13397; bugfix on 0.2.3.11-alpha.
This happened because we changed AutomapHostsSuffixes to replace "."
with "", since a suffix of "" means "match everything." But our
option handling code for CSV options likes to remove empty entries
when it re-parses stuff.
Instead, let "." remain ".", and treat it specially when we're
checking for a match.
Fixes bug 12509; bugfix on 0.2.0.1-alpha.
This allows hidden services to disable the anti-scanning feature
introduced in 0.2.6.2-alpha. With this option not set, a connection
to an unlisted port closes the circuit. With this option set, only
a RELAY_DONE cell is sent.
Closes ticket #14084.
Stop assuming that private addresses are local when checking
reachability in a TestingTorNetwork. Instead, when testing, assume
all OR connections are remote. (This is necessary due to many test
scenarios running all nodes on localhost.)
This assists in bootstrapping a testing Tor network.
Fixes bugs 13718 & 13924.
If the consensus does not contain Exits, Tor will only build internal
circuits. In this case, relevant statuses will contain the word "internal"
as indicated in the Tor control-spec.txt. When bootstrap completes,
Tor will be ready to handle an application requesting an internal
circuit to hidden services at ".onion" addresses.
If a future consensus contains Exits, exit circuits may become available.
Tor already notifies the user at "notice" level if they have no exits in
the consensus, and can therefor only build internal paths.
Consequential change from #13718.
Tor can now build circuits from a consensus with no exits.
But if it tries to build exit circuits, they fail and flood the logs.
The circuit types in the Exit Circuits list below will only be
built if the current consensus has exits. If it doesn't,
only the Internal Circuits will be built. (This can change
with each new consensus.)
Fixes bug #13814, causes fewer path failures due to #13817.
Exit Circuits:
Predicted Exit Circuits
User Traffic Circuits
Most AP Streams
Circuits Marked Exit
Build Timeout Circuits (with exits)
Internal Circuits:
Hidden Service Server Circuits
Hidden Service Client Circuits
Hidden Service AP Streams
Hidden Service Intro Point Streams
Circuits Marked Internal
Build Timeout Circuits (with no exits)
Other Circuits?
If the consensus has no exits (typical of a bootstrapping
test network), allow tor to build circuits once enough
descriptors have been downloaded.
When there are no exits, we always have "enough"
exit descriptors. (We treat the proportion of available
exit descriptors as 100%.)
This assists in bootstrapping a testing Tor network.
Fixes bug 13718.
Makes bug 13161's TestingDirAuthVoteExit non-essential.
(But still useful for speeding up a bootstrap.)
Add router_have_consensus_path() which reports whether
the consensus has exit paths, internal paths, or whether it
just doesn't know.
Used by #13718 and #13814.
count_usable_descriptors now uses named exit_only values:
USABLE_DESCRIPTOR_ALL
USABLE_DESCRIPTOR_EXIT_ONLY
Add debug logging code for descriptor counts.
This (hopefully) resolves nickm's request in bug 13718 to improve
argument readability in nodelist.c.
choose_good_entry_server() now excludes current entry
guards and their families, unless we're in a test network,
and excluding guards would exclude all nodes.
This typically occurs in incredibly small tor networks,
and those using TestingAuthVoteGuard *
This is an incomplete fix, but is no worse than the previous
behaviour, and only applies to minimal, testing tor networks
(so it's no less secure).
Discovered as part of #13718.
Make hidden service port scanning harder by sending back REASON_DONE which
does not disclose that it was in fact an exit policy issue. After that, kill
the circuit immediately to avoid more bad requests on it.
This means that everytime an hidden service exit policy does match, the user
(malicious or not) needs to build a new circuit.
Fixes#13667.
Signed-off-by: David Goulet <dgoulet@ev0ke.net>
Otherwise we risk a subsequent memdup or memcpy copying
uninitialized RAM into some other place that might eventually expose
it. Let's make sure that doesn't happen.
Closes ticket 14041
When V3AuthVotingInterval is low, decrease the delay on the
If-Modified-Since header passed to directory servers.
This allows us to obtain consensuses promptly when the consensus
interval is very short.
This assists in bootstrapping a testing Tor network.
Fixes bugs 13718 & 13963.
Decrease minimum consensus interval to 10 seconds
when TestingTorNetwork is set. (Or 5 seconds for
the first consensus.)
Fix code that assumes larger interval values.
This assists in quickly bootstrapping a testing
Tor network.
Fixes bugs 13718 & 13823.
Stop requiring exits to have non-zero bandwithcapacity in a
TestingTorNetwork. Instead, when TestingMinExitFlagThreshold is 0,
ignore exit bandwidthcapacity.
This assists in bootstrapping a testing Tor network.
Fixes bugs 13718 & 13839.
Makes bug 13161's TestingDirAuthVoteExit non-essential.
The address of an array in the middle of a structure will
always be non-NULL. clang recognises this and complains.
Disable the tautologous and redundant check to silence
this warning.
Fixes bug 14001.
The address of an array in the middle of a structure will
always be non-NULL. clang recognises this and complains.
Disable the tautologous and redundant check to silence
this warning.
A comment about an IPv6 address string incorrectly refers
to an IPv4 address format.
A log buffer is sized 10024 rather than 10240.
Fixes bug 14001.
In circuit_get_open_circ_or_launch(), for a rendezvous circuit,
rend_client_rendcirc_has_opened() but circuit_has_opened() is preferred here
since it will call the right function for a specific circuit purpose.
Furthermore, a controller event is triggered where the former did not.
Signed-off-by: David Goulet <dgoulet@ev0ke.net>
We add a compression level argument to tor_zlib_new, and use it to
determine how much memory to allocate for the zlib object. We use the
existing level by default, but shift to smaller levels for small
requests when we have been over 3/4 of our memory usage in the past
half-hour.
Closes ticket 11791.
When closing parallel introduction points, the given reason (timeout)
was actually changed to "no reason" thus when the circuit purpose was
CIRCUIT_PURPOSE_C_INTRODUCE_ACK_WAIT, we were reporting an introduction
point failure and flagging it "unreachable". After three times, that
intro point gets removed from the rend cache object.
In the case of CIRCUIT_PURPOSE_C_INTRODUCING, the intro point was
flagged has "timed out" and thus not used until the connection to the HS
is closed where that flag gets reset.
This commit adds an internal circuit reason called
END_CIRC_REASON_IP_NOW_REDUNDANT which tells the closing circuit
mechanism to not report any intro point failure.
This has been observed while opening hundreds of connections to an HS on
different circuit for each connection. This fix makes this use case to
work like a charm.
Fixes#13698.
Signed-off-by: David Goulet <dgoulet@ev0ke.net>
Instead, generate new keys, and overwrite the empty key files.
Adds FN_EMPTY to file_status_t and file_status.
Fixes bug 13111.
Related changes due to review of FN_FILE usage:
Stop generating a fresh .old RSA key file when the .old file is missing.
Avoid overwriting .old key files with empty key files.
Skip loading zero-length extra info store, router store, stats, state,
and key files.
Stop crashing when a NULL filename is passed to file_status(),
instead, return FN_ERROR.
Also return FN_ERROR when a zero-length filename is passed to file_status().
Fixed as part of bug 13111.
This is meant to prevent memory corruption bugs from doing
unspeakable infinite-loop-like things to the hashtables. Addresses
ticket 11737. We should disable these if they turn out to be
expensive.
Authorities are no longer voting on Named, so specifying nodes by
nickname isn't a clever thing to do. (Not that it ever was!) So
remove the documentation that suggests that you should do it.
Additionally, add proper cross-references to our __node__ lists, and
explain about the optional $ before identity digests.
Also, the oxford comma: endorsed by Steven Pinker, my spouse, and my
11th grade English teacher.
Closes 13381.
We were only using it when smartlist_choose_node_by_bandwidth_weights
failed. But that function could only fail in the presence of
buggy/ancient authorities or in the absence of a consensus. Either
way, it's better to use sensible defaults and a nicer algorithm.
Now, if a router ever changes its microdescriptor, but the new
microdescriptor SHA256 hash has the same 160-bit prefix as the old
one, we treat it as a new microdescriptor when deciding whether to
copy status information.
(This function also is used to compare SHA1 digests of router
descriptors, but don't worry: the descriptor_digest field either holds
a SHA256 hash, or a SHA1 hash padded with 0 bytes.)
Silence clang warnings under --enable-expensive-hardening, including:
+ implicit truncation of 64 bit values to 32 bit;
+ const char assignment to self;
+ tautological compare; and
+ additional parentheses around equality tests. (gcc uses these to
silence assignment, so clang warns when they're present in an
equality test. But we need to use extra parentheses in macros to
isolate them from other code).
