This implements "algorithm 1" from my discussion of bug #9072: on OOM,
find the circuits with the longest queues, and kill them. It's also a
fix for #9063 -- without the side-effects of bug #9072.
The memory bounds aren't perfect here, and you need to be sure to
allow some slack for the rest of Tor's usage.
This isn't a perfect fix; the rest of the solutions I describe on
codeable.
In my #7912 fix, there wasn't any code to remove entries from the
(channel, circuit ID)->circuit map corresponding to queued but un-sent
DESTROYs.
Spotted by skruffy. Fixes bug 9082; bug not in any released Tor.
I added the code to pass a destroy cell to a queueing function rather
than writing it immediately, and the code to remember that we
shouldn't reuse the circuit id until the destroy is actually sent, and
the code to release the circuit id once the destroy has been sent...
and then I finished by hooking destroy_cell_queue into the rest of
Tor.
This is a reprise of the fix in bdff7e3299d78; 6905c1f6 reintroduced
that bug. Briefly: windows doesn't seem to like deleting a mapped
file. I tried adding the PROT_SHARED_DELETE flag to the createfile
all, but that didn't actually fix this issue. Fortunately, the unit
test I added in 4f4fc63fea should
prevent us from making this particular screw-up again.
This patch also tries to limit the crash potential of a failure to
write by a little bit, although it could do a better job of retaining
microdescriptor bodies.
Fix for bug 8822, bugfix on 0.2.4.12-alpha.
There's an assertion failure that can occur if a connection has
optimistic data waiting, and then the connect() call returns 0 on the
first attempt (rather than -1 and EINPROGRESS). That latter behavior
from connect() appears to be an (Open?)BSDism when dealing with remote
addresses in some cases. (At least, I've only seen it reported with
the BSDs under libevent, even when the address was 127.0.0.1. And
we've only seen this problem in Tor with OpenBSD.)
Fixes bug 9017; bugfix on 0.2.3.1-alpha, which first introduced
optimistic data. (Although you could also argue that the commented-out
connection_start_writing in 155c9b80 back in 2002 is the real source
of the issue.)
A new option TestingV3AuthVotingStartOffset is added which offsets the
starting time of the voting interval. This is possible only when
TestingTorNetwork is set.
This patch makes run_scheduled_events() check for new consensus
downloads every second when TestingTorNetwork, instead of every
minute. This should be fine, see #8532 for reasoning.
This patch also brings MIN_VOTE_SECONDS and MIN_DIST_SECONDS down from
20 to 2 seconds, unconditionally. This makes sanity checking of
misconfiguration slightly less sane.
Addresses #8532.
You can't use != to compare arbitary members of or_options_t.
(Also, generate a better error message to say which Testing* option
was set.)
Fix for bug 8992. Bugfix on b0d4ca49. Bug not in any released Tor.
- Rename n_read and n_written in origin_circuit_t to make it clear that
these are only used for CIRC_BW events.
- Extract new code in control_update_global_event_mask to new
clear_circ_bw_fields function.
- Avoid control_event_refill_global function with 13 arguments and
increase code reuse factor by moving more code from control.c to
connection.c.
- Avoid an unsafe uint32_t -> int cast.
- Add TestingEnableTbEmptyEvent option.
- Prepare functions for testing.
- Rename a few functions and improve documentation.
- Move cell_command_to_string from control.c to command.c.
- Use accessor for global_circuitlist instead of extern.
- Add a struct for cell statistics by command instead of six arrays.
- Split up control_event_circuit_cell_stats by using two helper functions.
- Add TestingEnableCellStatsEvent option.
- Prepare functions for testing.
- Rename a few variables and document a few things better.
- Move new ID= parameter in ORCONN event to end. Avoids possible trouble
from controllers that parse parameters by position, even though they
shouldn't.
Create new methods check_or_create_data_subdir() and
write_to_data_subdir() in config.c and use them throughout
rephist.c and geoip.c.
This should solve ticket #4282.
This is a fix for bug 8844, where eugenis correctly notes that there's
a sentinel value at the end of the list-of-freelists that's never
actually checked. It's a bug since the first version of the chunked
buffer code back in 0.2.0.16-alpha.
This would probably be a crash bug if it ever happens, but nobody's
ever reported something like this, so I'm unsure whether it can occur.
It would require write_to_buf, write_to_buf_zlib, read_to_buf, or
read_to_buf_tls to get an input size of more than 32K. Still, it's a
good idea to fix this kind of thing!
It appears that moria1 crashed because of one instance of this (the
one in router_counts_toward_thresholds). The other instance I fixed
won't actually have broken anything, but I think it's more clear this
way.
Fixes bug 8833; bugfix on 0.2.4.12-alpha.
We need to subtract both the current built circuits *and* the attempted
circuits from the attempt count during scaling, since *both* have already been
counted there.
It sure is a good thing we can run each test in its own process, or
else the amount of setup I needed to do to make this thing work
would have broken all the other tests.
Test mocking would have made this easier to write too.
Now we can compute the hash and signature of a dirobj before
concatenating the smartlist, and we don't need to play silly games
with sigbuf and realloc any more.
I believe this was introduced in 6bc071f765, which makes
this a fix on 0.2.0.10-alpha. But my code archeology has not extended
to actually testing that theory.
We were mixing bandwidth file entries (which are in kilobytes) with
router_get_advertised_bw() entries, which were in bytes.
Also, use router_get_advertised_bandwidth_capped() for credible_bandwidth.
Since 7536c40 only DNS results for real SOCKS requests are added to the cache,
but not DNS results for DNSPort queries or control connection RESOLVE queries.
Only cache additions would trigger ADDRMAP events on successful resolve.
Change it so that DNS results received after a RESOLVE command also generate
ADDRMAP events.
There was a bug in Tor prior to 0.2.4.10-alpha that allowed counts to
become invalid. Clipping the counts at startup allows us to rule out
log messages due to corruption from these prior Tor versions.
This was causing dirauths to emit flag weight validation warns if there
was a sufficiently large amount of badexit bandwidth to make a difference in
flag weight results.
It seems that some versions of clang that would prefer the
-Wswitch-enum compiler flag to warn about switch statements with
missing enum values, even if those switch statements have a
default.
Fixes bug 8598; bugfix on 0.2.4.10-alpha.
It can never be NULL, since it's an array in bridge_line_t.
Introduced in 266f8cddd8. Found by coverity; this is CID 992691. Bug
not in any released Tor.
If we get a write error on a SOCKS connection, we can't send a
SOCKS reply, now can we?
This bug has been here since 36baf7219, where we added the "hey, I'm
closing an AP connection but I haven't finished the socks
handshake!" message. It's bug 8427.
Also, don't call the exit node 'reject *' unless our decision to pick
that node was based on a non-summarized version of that node's exit
policy.
rransom and arma came up with the ideas for this fix.
Fix for 7582; the summary-related part is a bugfix on 0.2.3.2-alpha.
When we're hibernating, the main reqason we can't bootstrap will
always be that we're hibernating: reporting anything else at severity
WARN is pointless.
Fixes part of 7302.
This bug affects hosts where time_t is unsigned, which AFAICT does
not include anything we currently support. (It _does_ include
OpenVMS, about a month of BSD4.2's history[1], and a lot of the 1970s.)
There are probably more bugs when time_t is unsigned. This one was
[1] http://mail-index.netbsd.org/tech-userlevel/1998/06/04/0000.html
This time, I'm checking whether our calculated offset matches our
real offset, in each case, as we go along. I don't think this is
the bug, but it can't hurt to check.
This should have been 2 bytes all along, since version numbers can
be 16 bits long. This isn't a live bug, since the call to
is_or_protocol_version_known in channel_tls_process_versions_cell
will reject any version number not in the range 1..4. Still, let's
fix this before we accidentally start supporting version 256.
Reported pseudonymously. Fixes bug 8062; bugfix on 0.2.0.10-alpha --
specifically, on commit 6fcda529, where during development I
increased the width of a version to 16 bits without changing the
type of link_proto.
Our ++ should have been += 2. This means that we'd accept version
numbers even when they started at an odd position.
This bug should be harmless in practice for so long as every version
number we allow begins with a 0 byte, but if we ever have a version
number starting with 1, 2, 3, or 4, there will be trouble here.
Fix for bug 8059, reported pseudonymously. Bugfix on 0.2.0.10-alpha
-- specifically, commit 6fcda529, where during development I
increased the width of a version to 16 bits without changing the
loop step.
I have no idea whether b0rken clients will DoS the network if the v2
authorities all turn this on or not. It's experimental. See #6783 for
a description of how to test it more or less safely, and please be
careful!
Now that circid_t is 4 bytes long, the default integer promotions will
leave it alone when sizeof(int) == 4, which will leave us formatting an
unsigned as an int. That's technically undefined behavior.
Fixes bug 8447 on bfffc1f0fc. Bug not
in any released Tor.
In a number of places, we decrement timestamp_dirty by
MaxCircuitDirtiness in order to mark a stream as "unusable for any
new connections.
This pattern sucks for a few reasons:
* It is nonobvious.
* It is error-prone: decrementing 0 can be a bad choice indeed.
* It really wants to have a function.
It can also introduce bugs if the system time jumps backwards, or if
MaxCircuitDirtiness is increased.
So in this patch, I add an unusable_for_new_conns flag to
origin_circuit_t, make it get checked everywhere it should (I looked
for things that tested timestamp_dirty), and add a new function to
frob it.
For now, the new function does still frob timestamp_dirty (after
checking for underflow and whatnot), in case I missed any cases that
should be checking unusable_for_new_conns.
Fixes bug 6174. We first used this pattern in 516ef41ac1,
which I think was in 0.0.2pre26 (but it could have been 0.0.2pre27).
Without this patch, there's no way to know what went wrong when we
fail to parse a torrc line entirely (that is, we can't turn it into
a K,V pair.) This patch introduces a new function that yields an
error message on failure, so we can at least tell the user what to
look for in their nonfunctional torrc.
(Actually, it's the same function as before with a new name:
parse_config_line_from_str is now a wrapper macro that the unit
tests use.)
Fixes bug 7950; fix on 0.2.0.16-alpha (58de695f90) which first
introduced the possibility of a torrc value not parsing correctly.
This patch moves the measured_bw field and the has_measured_bw field
into vote_routerstatus_t, since only votes have 'Measured=XX' set on
their weight line.
I also added a new bw_is_unmeasured flag to routerstatus_t to
represent the Unmeasured=1 flag on a w line. Previously, I was using
has_measured_bw for this, which was quite incorrect: has_measured_bw
means that the measured_bw field is set, and it's probably a mistake
to have it serve double duty as meaning that 'baandwidth' represents a
measured value.
While making this change,I also found a harmless but stupid bug in
dirserv_read_measured_bandwidths: It assumes that it's getting a
smartlist of routerstatus_t, when really it's getting a smartlist of
vote_routerstatus_t. C's struct layout rules mean that we could never
actually get an error because of that, but it's still quite incorrect.
I fixed that, and in the process needed to add two more sorting and
searching helpers.
Finally, I made the Unmeasured=1 flag get parsed. We don't use it for
anything yet, but someday we might.
This isn't complete yet -- the new 2286 unit test doesn't build.
Instead of capping whenever a router has fewer than 3 measurements,
we cap whenever a router has fewer than 3 measurements *AND* there
are at least 3 authorities publishing measured bandwidths.
We also generate bandwidth lines with a new "Unmeasured=1" flag,
meaning that we didn't have enough observations for a node to use
measured bandwidth values in the authority's input, whether we capped
it or not.
Stop marking every relay as having been down for one hour every
time we restart a directory authority. These artificial downtimes
were messing with our Stable and Guard flag calculations.
Fixes bug 8218 (introduced by the fix for 1035). Bugfix on 0.2.2.23-alpha.
Apparently something in the directory guard code made it possible
for the same node to get added as a guard over and over when there
were no actual running guard nodes.
Relays used to check every 10 to 60 seconds, as an accidental side effect
of calling directory_fetches_from_authorities() when considering doing
a directory fetch. The fix for bug 1992 removes that side effect. At the
same time, bridge relays never had the side effect, leading to confused
bridge operators who tried crazy tricks to get their bridges to notice
IP address changes (see ticket 1913).
The new behavior is to reinstate an every-60-seconds check for both
public relays and bridge relays, now that the side effect is gone.
For example, we were doing a resolve every time we think about doing a
directory fetch. Now we reuse the cached answer in some cases.
Fixes bugs 1992 (bugfix on 0.2.0.20-rc) and 2410 (bugfix on
0.1.2.2-alpha).
When we compute the estimated microseconds we need to handle our
pending onionskins, we could (in principle) overflow a uint32_t if
we ever had 4 million pending onionskins before we had any data
about how onionskins take. Nevertheless, let's compute it properly.
Fixes bug 8210; bugfix on 0.2.4.10. Found by coverity; this is CID
980651.
Coverity is worried that we're checking entry_conn in some cases,
but not in the case where we set entry_conn->pending_optimistic_data.
This commit should calm it down (CID 718623).
The refactoring in commit 471ab34032 wasn't complete enough: we
were checking the auth_len variable, but never actually setting it,
so it would never seem that authentication had been provided.
This commit also removes a bunch of unused variables from
rend_service_introduce, whose unusedness we hadn't noticed because
we were wiping them at the end of the function.
Fix for bug 8207; bugfix on 0.2.4.1-alpha.
It returns the method by which we decided our public IP address
(explicitly configured, resolved from explicit hostname, guessed from
interfaces, learned by gethostname).
Now we can provide more helpful log messages when a relay guesses its IP
address incorrectly (e.g. due to unexpected lines in /etc/hosts). Resolves
ticket 2267.
While we're at it, stop sending a stray "(null)" in some cases for the
server status "EXTERNAL_ADDRESS" controller event. Resolves bug 8200.
since router_parse_entry_from_string() already checks whether
!tor_inet_aton(router->address, &in)
(And no need to print address, since router_describe does that.)
- Document the key=value format.
- Constify equal_sign_pos.
- Pass some strings that are about to be logged to escape().
- Update documentation and fix some bugs in tor_escape_str_for_socks_arg().
- Use string_is_key_value() in parse_bridge_line().
- Parenthesize a forgotten #define
- Add some more comments.
- Add some more unit test cases.
This check isn't necessary (see comment on #7801), but it took at
least two smart people a little while to see why it wasn't necessary,
so let's have it in to make the code more readable.
We need a weak RNG in a couple of places where the strong RNG is
both needless and too slow. We had been using the weak RNG from our
platform's libc implementation, but that was problematic (because
many platforms have exceptionally horrible weak RNGs -- like, ones
that only return values between 0 and SHORT_MAX) and because we were
using it in a way that was wrong for LCG-based weak RNGs. (We were
counting on the low bits of the LCG output to be as random as the
high ones, which isn't true.)
This patch adds a separate type for a weak RNG, adds an LCG
implementation for it, and uses that exclusively where we had been
using the platform weak RNG.
If we're deciding on a node's bandwidth based on "Bandwidth="
declarations, clip it to "20" or to the maxunmeasuredbw parameter,
if it's voted on.
This adds a new consensus method.
This is "part A" of bug 2286
Authorities don't set is_possible_guard on node_t, so they were
never deciding that they could build enough paths. This is a quick
and dirty fix.
Bug not in any released version of Tor
These seem to have gotten conflicted out of existence while mike was
working on path bias stuff.
Thanks to sysrqb for collecting these in a handy patch.
Now we can specify to skip bridges that wouldn't be able to answer the
type of dir fetch we're launching.
It's still the responsibility of the rest of the code to prevent us from
launching a given dir fetch if we have no bridges that could handle it.
Now as we move into a future where most bridges can handle microdescs
we will generally find ourselves using them, rather than holding back
just because one of our bridges doesn't use them.
When we first implemented TLS, we assumed in conneciton_handle_write
that a TOR_TLS_WANT_WRITE from flush_buf_tls meant that nothing had
been written. But when we moved our buffers to a ring buffer
implementation back in 0.1.0.5-rc (!), we broke that invariant: it's
possible that some bytes have been written but nothing.
That's bad. It means that if we do a sequence of TLS writes that ends
with a WANTWRITE, we don't notice that we flushed any bytes, and we
don't (I think) decrement buckets.
Fixes bug 7708; bugfix on 0.1.0.5-rc
Also, deprecate the torrc options for the scaling values. It's unlikely anyone
but developers will ever tweak them, even if we provided a single ratio value.
This is meant to avoid conflict with the built-in log() function in
math.h. It resolves ticket 7599. First reported by dhill.
This was generated with the following perl script:
#!/usr/bin/perl -w -i -p
s/\blog\(LOG_(ERR|WARN|NOTICE|INFO|DEBUG)\s*,\s*/log_\L$1\(/g;
s/\blog\(/tor_log\(/g;
Instead of hardcoding the minimum fraction of possible paths to 0.6, we
take it from the user, and failing that from the consensus, and
failing that we fall back to 0.6.
Previously we did this based on the fraction of descriptors we
had. But really, we should be going based on what fraction of paths
we're able to build based on weighted bandwidth, since otherwise a
directory guard or two could make us behave quite oddly.
Implementation for feature 5956
If any circuits were opened during a scaling event, we were scaling attempts
and successes by different amounts. This leads to rounding error.
The fix is to record how many circuits are in a state that hasn't been fully
counted yet, and subtract that before scaling, and add it back afterwords.
Since they use RELAY_EARLY (which can be seen by all hops on the path),
it's not safe to say they actually count as a successful use.
There are also problems with trying to allow them to finish extending due to
the circuit purpose state machine logic. It is way less complicated (and
possibly more semantically coherent) to simply wait until we actually try to
do something with them before claiming we 'used' them.
Also, we shouldn't call timed out circuits 'used' either, for semantic
consistency.
An adversary could let the first stream request succeed (ie the resolve), but
then tag and timeout the remainder (via cell dropping), forcing them on new
circuits.
Rolling back the state will cause us to probe such circuits, which should lead
to probe failures in the event of such tagging due to either unrecognized
cells coming in while we wait for the probe, or the cipher state getting out
of sync in the case of dropped cells.
Path use bias measures how often we can actually succeed using the circuits we
actually try to use. It is a subset of path bias accounting, but it is
computed as a separate statistic because the rate of client circuit use may
vary depending on use case.
This is a minimal refactoring to expose the weighted bandwidth
calculations for each node so I can use them to see what fraction of
nodes, weighted by bandwidth, we have descriptors for.
This is ticket 7706, reported by "bugcatcher." The rationale here
is that if somebody says 'ExcludeNodes {tv}', then they probably
don't just want to block definitely Tuvaluan nodes: they also want
to block nodes that have unknown country, since for all they know
such nodes are also in Tuvalu.
This behavior is controlled by a new GeoIPExcludeUnknown autobool
option. With the default (auto) setting, we exclude ?? and A1 if
any country is excluded. If the option is 1, we add ?? and A1
unconditionally; if the option is 0, we never add them.
(Right now our geoip file doesn't actually seem to include A1: I'm
including it here in case it comes back.)
This feature only takes effect if you have a GeoIP file. Otherwise
you'd be excluding every node.
The implementation is pretty straightforward: parse_extended_hostname() is
modified to drop any leading components from an address like
'foo.aaaaaaaaaaaaaaaa.onion'.
This is an automatically generated commit, from the following perl script,
run with the options "-w -i -p".
s/smartlist_string_num_isin/smartlist_contains_int_as_string/g;
s/smartlist_string_isin((?:_case)?)/smartlist_contains_string$1/g;
s/smartlist_digest_isin/smartlist_contains_digest/g;
s/smartlist_isin/smartlist_contains/g;
s/digestset_isin/digestset_contains/g;
In 6fbdf635 we added a couple of statements like:
if (test) {
...
};
The extraneous semicolons there get flagged as worrisome empty
statements by the cparser library, so let's fix them.
Patch by Christian Grothoff; fixes bug 7115.
Otherwise, it's possible to create streams or circuits with these
bogus IDs, leading to orphaned circuits or streams, or to ones that
can cause bandwidth DOS problems.
Fixes bug 7889; bugfix on all released Tors.
In general, if we tried to use a circ for a stream, but then decided to place
that stream on a different circuit, we need to probe the original circuit
before deciding it was a "success".
We also need to do the same for cannibalized circuits that go unused.
This makes removing items from the middle of the queue into an O(1)
operation, which could prove important as we let onionqueues grow
longer.
Doing this actually makes the code slightly smaller, too.
The right way to set "MaxOnionsPending" was to adjust it until the
processing delay was appropriate. So instead, let's measure how long
it takes to process onionskins (sampling them once we have a big
number), and then limit the queue based on its expected time to
finish.
This change is extra-necessary for ntor, since there is no longer a
reasonable way to set MaxOnionsPending without knowing what mix of
onionskins you'll get.
This patch also reserves 1/3 of the onionskin spots for ntor
handshakes, on the theory that TAP handshakes shouldn't be allowed to
starve their speedier cousins. We can change this later if need be.
Resolves 7291.
The unit of work sent to a cpuworker is now a create_cell_t; its
response is now a created_cell_t. Several of the things that call or
get called by this chain of logic now take create_cell_t or
created_cell_t too.
Since all cpuworkers are forked or spawned by Tor, they don't need a
stable wire protocol, so we can just send structs. This saves us some
insanity, and helps p
As elsewhere, it makes sense when adding or extending a cell type to
actually make the code to parse it into a separate tested function.
This commit doesn't actually make anything use these new functions;
that's for a later commit.
The handshake_digest field was never meaningfully a digest *of* the
handshake, but rather is a digest *from* the handshake that we exapted
to prevent replays of ESTABLISH_INTRO cells. The ntor handshake will
generate it as more key material rather than taking it from any part
of the circuit handshake reply..
I'm going to want a generic "onionskin" type and set of wrappers, and
for that, it will be helpful to isolate the different circuit creation
handshakes. Now the original handshake is in onion_tap.[ch], the
CREATE_FAST handshake is in onion_fast.[ch], and onion.[ch] now
handles the onion queue.
This commit does nothing but move code and adjust header files.
Here we try to handle curve25519 onion keys from generating them,
loading and storing them, publishing them in our descriptors, putting
them in microdescriptors, and so on.
This commit is untested and probably buggy like whoa
This patch moves curve25519_keypair_t from src/or/onion_ntor.h to
src/common/crypto_curve25519.h, and adds new functions to generate,
load, and store keypairs.
The ntor handshake--described in proposal 216 and in a paper by
Goldberg, Stebila, and Ustaoglu--gets us much better performance than
our current approach.
Our old warn_nonlocal_client_ports() would give a bogus warning for
every nonlocal port every time it parsed any ports at all. So if it
parsed a nonlocal socksport, it would complain that it had a nonlocal
socksport...and then turn around and complain about the nonlocal
socksport again, calling it a nonlocal transport or nonlocal dnsport,
if it had any of those.
Fixes bug 7836; bugfix on 0.2.3.3-alpha.
mr-4 reports on #7799 that he was seeing it several times per second,
which suggests that things had gone very wrong.
This isn't a real fix, but it should make Tor usable till we can
figure out the real issue.
This implements the server-side of proposal 198 by detecting when
clients lack the magic list of ciphersuites that indicates that
they're lying faking some ciphers they don't really have. When
clients lack this list, we can choose any cipher that we'd actually
like. The newly allowed ciphersuites are, currently, "All ECDHE-RSA
ciphers that openssl supports, except for ECDHE-RSA-RC4".
The code to detect the cipher list relies on on (ab)use of
SSL_set_session_secret_cb.
It's important not to call choose_array_element_by_weight and then
pass its return value unchecked to smartlist_get : it is allowed to
return -1.
Fixes bug 7756; bugfix on 4e3d07a6 (not in any released Tor)
This is good enough to give P_success >= 999,999,999/1,000,000,000 so
long as the address space is less than 97.95 full. It'd be ridiculous
for that to happen for IPv6, and usome reasonable assumptions, it
would also be pretty silly for IPv4.
With an IPv6 virtual address map, we can basically hand out a new
IPv6 address for _every_ address we connect to. That'll be cool, and
will let us maybe get around prop205 issues.
This uses some fancy logic to try to make the code paths in the ipv4
and the ipv6 case as close as possible, and moves to randomly
generated addresses so we don't need to maintain those stupid counters
that will collide if Tor restarts but apps don't.
Also has some XXXX items to fix to make this useful. More design
needed.
This function gives us a single place to set reasonable default flags
for port_cfg_t entries, to avoid bugs like the one where we weren't
setting ipv4_traffic_ok to 1 on SocksPorts initialized in an older
way.
(This is part 2 of making DNS cache use enabled/disabled on a
per-client port basis. This implements the CacheIPv[46]DNS options,
but not the UseCachedIPv[46] ones.)
(This is part 1 of making DNS cache use enabled/disabled on a
per-client port basis. These options are shuffled around correctly,
but don't do anything yet.)
We want to be saying fast_mem{cmp,eq,neq} when we're doing a
comparison that's allowed to exit early, or tor_mem{cmp,eq,neq} when
we need a data-invariant timing. Direct use of memcmp tends to imply
that we haven't thought about the issue.
This has several advantages, including more resilience to ambient failure.
I still need to rename all the first_hop vars tho.. Saving that for a separate
commit.
Turns out there's more than one way to block a tagged circuit.
This seems to successfully handle all of the normal exit circuits. Hidden
services need additional tweaks, still.
This replaces the old FallbackConsensus notion, and should provide a
way -- assuming we pick reasonable nodes! -- to give clients
suggestions of placs to go to get their first consensus.
Now creating a dir_server_t and adding it are separate functions, and
there are frontend functions for adding a trusted dirserver and a
fallback dirserver.
We use trusted_dir_server_t for two pieces of functionality: a list of
all directory authorities, and a list of initial places to look for
a directory. With this patch we start to separate those two roles.
There is as of now no actual way to be a fallback directory without being
an authority.
This is a customizable extract-and-expand HMAC-KDF for deriving keys.
It derives from RFC5869, which derives its rationale from Krawczyk,
H., "Cryptographic Extraction and Key Derivation: The HKDF Scheme",
Proceedings of CRYPTO 2010, 2010, <http://eprint.iacr.org/2010/264>.
I'm also renaming the existing KDF, now that Tor has two of them.
This is the key derivation scheme specified in ntor.
There are also unit tests.
This one is necessary for sending BEGIN cells with sane flags when
self-testing a directory port. All real entry connections were
getting their ipv{4,6}_traffic_ok flags set from their listeners, and
for begindir entry connections we didn't care, but for directory
self-testing, we had a problem.
Fixes at least one more case of 7493; if there are more lingering
cases of 7493, this might fix them too.
Bug not in any released version of Tor.
Looks like when i was writing the code to set the ipv4_traffic flag on
port_cfg_t, I missed some cases, such as the one where the port was
set from its default value.
Fix for 7493. Bug not in any released Tor.
Previously, I was freaking out about passing an unspec address to
dns_found_answer() on an error, since I was using the address type to
determine whether the error was an error on an ipv4 address lookup or
on an ipv6 address lookup. But now dns_found_answer() has a separate
orig_query_type argument to tell what kind of query it is, so there's
no need to freak out.
* If there's an IPv4 and an IPv6 address, return both in the resolved
cell.
* Treat all resolve requests as permitting IPv6, since by the spec they're
allowed to, and by the code that won't break anything.
IPv4-only exits have an implicit "reject [::]/0", which was making
policy_is_reject_star() return 1 for them, making us refuse to do
hostname lookups.
This fix chanes policy_is_reject_star() to ask about which family we meant.
The code previously detected wildcarding and replaced wildcarded
answers with DNS_STATUS_FAILED_PERMANENT. But that status variable
was no longer used! Remove the status variable, and instead change
the value of 'result' in evdns_callback.
Thank goodness for compiler warnings. In this case,
unused-but-set-variable.
Thanks to Linus for finding this one.
