- Add a changes/ file.
- Make it compile under --enable-gcc-warnings.
- Update the file-level documentation of src/or/transports.c.
- Only update descriptor if at least a managed proxy was configured.
- Add our external IP address to the extra-info descriptor instead of 0.0.0.0.
This could result in bizarre window values. Report and patch
contributed pseudymously. Fixes part of bug 6271. This bug was
introduced before the first Tor release, in svn commit r152.
(bug 6271, part a.)
This reverts commit c32ec9c425.
It turns out the two sides of the circuit don't actually stay in sync,
so it is perfectly normal for the circuit window on the exit relay to
grow to 2000+. We should fix that bug and then reconsider this patch.
I only check on circuits, not streams, since bloating your stream
window past the initial circuit window can't help you much.
Also, I compare to CIRCWINDOW_START_MAX so we don't have surprising
races if we lower CIRCWINDOW_START for an experiment.
With glibc 2.15 and clang 3.0, I get warnings from where we use the
strcpsn implementation in the header as strcspn(string, "="). This
is apparently because clang sees that part of the strcspn macro
expands to "="[2], and doesn't realize that that part of the macro
is only evaluated when "="[1] != 0.
The functions parse_{s,c}method_line() were using
tor_addr_port_lookup() which is capable of doing DNS lookups. DNS
lookups should not be necessary when parsing {C,S}METHOD lines.
The code that detected the source of a remapped address checked that
an address mapping's source was a given rewrite rule if addr_orig had
no .exit, and addr did have a .exit after processing that rule. But
addr_orig was formatted for logging: it was not the original address
at all, but rather was the address escaped for logging and possibly
replaced with "[scrubbed]".
This new logic will correctly set ADDRMAPSRC_NONE in the case when the
address starts life as a .exit address, so that AllowDotExit can work
again.
Fixes bug 6211; bugfix on 0.2.3.17-beta
It turns out this can happen. Even though there is no reason for
connections to be marked but reading, we leave them reading anyway,
so warning here is unwarranted. Let's turn that back on once we do
something sensible and disable reading when we mark. Bugfix for
6203 on Tor 0.2.3.17-beta.
Thanks to cypherpunks for pointing out the general stupidity of the
original code here.
On some platforms, the linker is perfectly happy to produce binaries
that won't run if you give it the wrong set of flags. So when not
cross-compiling, try to link-and-run a little test program, rather
than just linking it.
Possible fix for 6173.
Previously, a directory would check the latest NS consensus for
having the signatures the client wanted, and use that consensus's
valid_until time to set the HTTP lifetime. With this patch, the
directory looks at NS consensus or the microdesc consensus,
depending on what the client asked for.
The warning message of validate_pluggable_transports_config() is
superseded by the changes in the warning message of
connection_or_connect() when the proxy credentials can't be found.
This is a feature removal: we no longer fake any ciphersuite other
than the not-really-standard SSL_RSA_FIPS_WITH_3DES_EDE_CBC_SHA
(0xfeff). This change will let servers rely on our actually
supporting what we claim to support, and thereby let Tor migrate to
better TLS ciphersuites.
As a drawback, Tor instances that use old openssl versions and
openssl builds with ciphers disabled will no longer give the
"firefox" cipher list.
Manually removed range 0.116.0.0 to 0.119.255.255 which Maxmind says is
assigned to AT. This is very likely a bug in their database, because
0.0.0.0/8 is a reserved range.
From what I can tell, this configuration is usually a mistake, and
leads people to think that all their traffic is getting proxied when
in fact practically none of it is. Resolves the issue behind "bug"
4663.
The function is not guaranteed to NUL-terminate its output. It
*is*, however, guaranteed not to generate more than two bytes per
multibyte character (plus terminating nul), so the general approach
I'm taking is to try to allocate enough space, AND to manually add a
NUL at the end of each buffer just in case I screwed up the "enough
space" thing.
Fixes bug 5909.
This feature can make Tor relays less identifiable by their use of the
mod_ssl DH group, but at the cost of some usability (#4721) and bridge
tracing (#6087) regressions.
We should try to turn this on by default again if we find that the
mod_ssl group is uncommon and/or we move to a different DH group size
(see #6088). Before we can do so, we need a fix for bugs #6087 and
Resolves ticket #5598 for now.
These stats are currently discarded, but we might as well
hard-disable them on bridges, to be clean.
Fix for bug 5824; bugfix on 0.2.1.17-rc.
Patch originally by Karsten Loesing.
This code shouldn't have any effect in 0.2.3, since we already accept
(and handle) data received while we are expecting a renegotiation.
(That's because the 0.2.3.x handshake _does_ have data there instead of
the renegotiation.)
I'm leaving it in anyway, since if it breaks anything, we'll want it
broken in master too so we can find out about it. I added an XXX023
comment so that we can come back later and fix that.
This fixes a DoS issue where a client could send so much data in 5
minutes that they exhausted the server's RAM. Fix for bug 5934 and
6007. Bugfix on 0.2.0.20-rc, which enabled the v2 handshake.
It appears that when OpenSSL negotiates a 1.1 or 1.2 connection, and it
decides to renegotiate, the client will send a record with version "1.0"
rather than with the current TLS version. This would cause the
connection to fail whenever both sides had OpenSSL 1.0.1, and the v2 Tor
handshake was in use.
As a workaround, disable TLS 1.1 and TLS 1.2. When a later version of
OpenSSL is released, we can make this conditional on running a fixed
version of OpenSSL.
Alternatively, we could disable TLS 1.1 and TLS 1.2 only on the client
side. But doing it this way for now means that we not only fix TLS with
patched clients; we also fix TLS when the server has this patch and the
client does not. That could be important to keep the network running
well.
Fixes bug 6033.
Conflicts:
src/test/test_util.c
Merge the unit tests; I added some when I did this branch against
0.2.2, and then the test format changed and master added more tests.
Conflicts:
src/common/compat.h
Conflict was between replacement of MS_WINDOWS with _WIN32 in
master, and with removal of file_handle from tor_mmap_t struct in
close_file_mapping branch (for bug 5951 fix).
It turns out that if you set the third argument of
__attribute__(format) to 0, GCC and Clang will check the format
argument without expecting to find variadic arguments. This is the
correct behavior for vsnprintf, vasprintf, and vscanf.
I'm hoping this will fix bug 5969 (a clang warning) by telling clang that
the format argument to tor_vasprintf is indeed a format string.
On Windows, getsockname() on a nonblocking apparently won't work
until the connection is done connecting. On XP, it seems to fail by
reporting success and declaring that your address is INADDR_ANY. On the
Win8 preview, though, it fails more loudly and says WSAEINVAL.
Fix for bug 5374; bugfix on 0.1.1.14-alpha.
The parent of "/foo" is "/"; and "/" is its own parent.
This would cause Tor to fail if you tried to have a PF_UNIX control
socket in the root directory. That would be a stupid thing to do
for other reasons, but there's no reason to fail like _this_.
Bug found by Esteban Manchado Velázquez. Fix for bug 5089; bugfix on
Tor 0.2.2.26-beta. Unit test included.
Roger explains at
http://archives.seul.org/tor/talk/Nov-2011/msg00209.html :
"If you list your bridge as part of your family in the relay
descriptor, then everybody can learn your bridge fingerprint, and
they can look up your bridge's descriptor (and thus location) at
the bridge directory authority."
Now, we can't stop relays from listing bridges, but we can warn when
we notice a bridge listing anybody, which might help some.
This fixes bug 4657; it's a fix on 0.2.0.3-alpha, where bridges were
first introduced.
To hit this leak, you need to be a relay that gets a RESOLVE request
or an exit node getting a BEGIN or RESOLVE request. You must either
have unconfigured (and unconfigurable) nameservers, or you must have
somehow set DisableNetwork after a network request arrived but
before you managed to process it.
So, I doubt this is reached often. Still, a leak's a leak. Fix for
bug 5916; bugfix on 0.2.3.9-alpha and 0.1.2.1-alpha.
%f is correct; %lf is only needed with scanf. Apparently, on some
old BSDs, %lf is deprecated.
Didn't we do this before? Yes, we did. But we only got the
instances of %lf, not more complicated things like %.5lf . This
patch tries to get everything.
Based on a patch for 3894 by grarpamp.
These errors usually mean address exhaustion; reporting them as such
lets clients adjust their load to try other exits.
Fix for bug 4710; bugfix on 0.1.0.1-rc, which started using
END_STREAM_REASON_RESOURCELIMIT.
Previously, we only did this check at startup, which could lead to
us holding a guard indefinitely, and give weird results. Fixes bug
5380; bugfix on 0.2.1.14-rc.
(Patch by Roger; changes file and commit message by Nick)
Previously, we skipped everything that got invoked from
options_init_from_torrc. But some of the stuff in
options_act_reversible and options_act is actually important, like
reopening the logs.
Now, a SIGHUP always makes the effects of an options_set() happen,
even though the options haven't changed.
Fix for bug 5095; bugfix on 0.2.1.9-alpha, which introduced
__ReloadTorrcOnSIGHUP.
This would happen if the deliver window could become negative
because of an nonexistent connection. (Fortunately, _that_ can't
occur, thanks to circuit_consider_sending_sendme. Still, if we
change our windowing logic at all, we won't want this to become
triggerable.) Fix for bug 5541. Bugfix on 4a66865d, back from
0.0.2pre14. asn found this. Nice catch, asn!
We've been only treating SW_SERVER_HELLO_A as meaning that an SSL
handshake was happening. But that's not right: if the initial
attempt to write a ServerHello fails, we would get a callback in
state SW_SERVER_HELLO_B instead.
(That's "instead" and not "in addition": any failed attempt to write
the hello will fail and cause the info callback not to get written.)
Fix for bug 4592; bugfix on 0.2.0.13-alpha.
This tells the windows headers to give us definitions that didn't
exist before XP -- like the ones that we need for IPv6 support.
See bug #5861. We didn't run into this issue with mingw, since
mingw doesn't respect _WIN32_WINNT as well as it should for some of
its definitions.
Instead, allow packagers to put a 'TOR_BUILD_TAG' field in the
server descriptor to indicate a platform-specific value, if they
need to. (According to weasel, this was his use for the git- tag
previously.)
This is part of 2988
For uname-based detection, we now give only the OS name (e.g.,
"Darwin", "Linux".) For Windows, we give only the Operating System
name as inferred from dw(Major|Minor)version, (e.g., "Windows XP",
"Windows 7"), and whether the VER_NT_SERVER flag is set.
For ticket 2988.
This time, I follow grarpamp's suggestion and move the check for
.exit+AllowDotExit 0 to the top of connection_ap_rewrite_and_attach,
before any rewriting occurs. This way, .exit addresses are
forbidden as they arrive from a socks connection or a DNSPort
request, and not otherwise.
It _is_ a little more complicated than that, though. We need to
treat any .exit addresses whose source is TrackHostExits as meaning
that we can retry without that exit. We also need to treat any
.exit address that comes from an AutomapHostsOnResolve operation as
user-provided (and thus forbidden if AllowDotExits==0), so that
transitioning from AllowDotExits==1 to AllowDotExits==0 will
actually turn off automapped .exit addresses.
This patch changes the total serverdesc threshold from 25% to 75%
and the exit threshold from 33% to 50%. The goal is to make
initially constructed circuits less horrible, and to make initial
less awful (since fetching directory information in parallel with
whatever the user is trying to do can hurt their performance).
Implements ticket 3196.
We were doing an O(n) strlen in router_get_extrainfo_hash() for
every one we tried to parse. Instead, have
router_get_extrainfo_hash() take the length of the extrainfo as an
argument, so that when it's called from
extrainfo_parse_from_string(), it doesn't do a strlen() over the
whole pile of extrainfos.
If the authorities agreed on a sufficiently bad bwweightscale value
(<=0 or == INT32_MAX), the bandwidth algorithm could make the voters
assert while computing the consensus.
Fix for bug5786; bugfix on 0.2.2.17-alpha
The underlying strtoX functions handle overflow by saturating and
setting errno to ERANGE. If the min/max arguments to the
tor_parse_* functions are equal to the minimum/maximum of the
underlying type, then with the old approach, we wouldn't treat a
too-large value as genuinely broken.
Found this while looking at bug 5786; bugfix on 19da1f36 (in Tor
0.0.9), which introduced these functions.
We had been checking for EINVAL, but that means that SOCK_* isn't
supported, not that the syscall itself is missing.
Bugfix on 0.2.3.1-alpha, which started to use accept4.
We'd had our configure.in test include unistd.h unconditionally,
which would fail on Windows/mingw, even though environ _was_
declared there. Fix for 5704; bugfix on 0.2.3.13-alpha.
Thanks to Erinn for finding this and rransom for figuring out the
problem.
If the client uses a v2 cipherlist on the renegotiation handshake,
it looks as if they could fail to get a good cert chain from the
server, since they server would re-disable certificate chaining.
This patch makes it so the code that make the server side of the
first v2 handshake special can get called only once.
Fix for 4591; bugfix on 0.2.0.20-rc.
They boil down to:
- MS_WINDOWS is dead and replaced with _WIN32, but we let a few
instances creep in when we merged Esteban's tests.
- Capitalizing windows header names confuses mingw.
- #ifdef 0 ain't C.
- One unit test wasn't compiled on windows, but was being listed
anyway.
- One unit test was checking for the wrong value.
Gisle Vanem found and fixed the latter 3 issues.
Fixes bug #4528 "read_to_buf_tls(): Inconsistency in code".
This check was added back in 0.1.0.3-rc, but somehow we forgot to
leave it in when we refactored read_to_buf_tls in 0.1.0.5-rc.
(patch by Arturo; commit message and changes file by nickm)
Previously, we would reset it at the drop of a hat -- every time a second
passes without any of the intro-point circs already launched for the
service failing.
Fixes bug 4607.
This is just refactoring work here. The old logic was kind of
convoluted, especially after the bug 5572 fix. We don't actually need to
distinguish so many cases here. Dropping detection of the
"!old_options || !old_options->DynamicDHGroups" case is fine because
that's the same that we'd do for clients.
Also add a changes file for bug 5572.
The message only means that we're publishing a new descriptor when we
are actually in some kind of server mode, and publication is on.
Fix for bug 3942; bugfix on 0.2.3.2-alpha.
This fixes a side-channel attack on the (fortunately unused!)
BridgePassword option for bridge authorities. Fix for bug 5543;
bugfix on 0.2.0.14-alpha.
This is ticket 2479. Roger's original explanation was:
We have a series of bugs where relays publish a descriptor within
12 hours of their last descriptor, but the authorities drop it
because it's not different "enough" from the last one and it's
too close to the last one.
The original goal of this idea was to a) reduce the number of new
descriptors authorities accept (and thus have to store) and b)
reduce the total number of descriptors that clients and mirrors
fetch. It's a defense against bugs where relays publish a new
descriptor every minute.
Now that we're putting out one consensus per hour, we're doing
better at the total damage that can be caused by 'b'.
There are broader-scale design changes that would help here, and
we've had a trac entry open for years about how relays should
recognize that they're not in the consensus, or recognize when
their publish failed, and republish sooner.
In the mean time, I think we should change some of the parameters
to make the problem less painful.
When we started RefuseUnknownExits back in 0.2.2.11-alpha, we
started making exits act like they cache directory info (since they
need an up-to-date idea of who is really a router). But this
included fetching needless (unrecognized) authorities' certs, which
doesn't make any sense for them.
This is related to, but not necessarily the same as, the issue that
Ian reported for bug #2297.
(This patch is based on a patch from a user who I believe has asked
not to be named. If I'm wrong about that, please add the
appropriate name onto the changelog.)
==
Nick here. I tweaked this patch a little to make it apply cleanly to
master, to extract some common code into a function, and to replace
snprintf with tor_snprintf.
-- nickm
Specifically, it was a fix on 33e2053ebc, where we introduced the
WRA_* and ROUTER_* codes for dirserv_add_descriptor. Previously, we
had checked for a _negative_ return from dirserv_add_descriptor, which
meant "rejected". An insufficiently new descriptor would give a
0-valued return. But when we switched from numbers to enums, we got
this check wrong and had init_keys() give an error whenever the
descriptor wasn't accepted.
This mitigates an attack proposed by wanoskarnet, in which all of a
client's bridges collude to restrict the exit nodes that the client
knows about. Fixes bug 5343.
Since 0.2.3.1-alpha, we've supported the Linux extensions to socket(),
open(), socketpair(), and accept() that enable us to create an fd and
make it close-on-exec with a single syscall. This not only saves us a
syscall (big deal), but makes us less vulnerable to race conditions
where we open a socket and then exec before we can make it
close-on-exec.
But these extensions are not supported on all Linuxes: They were added
between 2.6.23 or so and 2.6.28 or so. If you were to build your Tor
against a recent Linux's kernel headers, and then run it with a older
kernel, you would find yourselve unable to open sockets. Ouch!
The solution here is that, when one of these syscalls fails with
EINVAL, we should try again in the portable way. This adds an extra
syscall in the case where we built with new headers and are running
with old ones, but it will at least allow Tor to work.
Fixes bug 5112; bugfix on 0.2.3.1-alpha.
The big change here is a patch (first added to Libevent by Ed Day)
to make sure that the CreateProcess forked-test trick works even
when the main test program is invoked without its .exe suffix.
Previously we'd been using "we have clock_gettime()" as a proxy for
"we need -lrt to link a static libevent". But that's not really
accurate: we should only add -lrt if searching for clock_gettime
function adds -lrt to our libraries.
in Makefile.am, we used it without quoting it, causing build failure if
your openssl/sed/sha1sum happened to live in a directory with a space in
it (very common on windows)
This reverts commit 55e8cae815.
The conversation from irc:
> weasel: i had intended to leave torrc.sample.in alone in maint-0.2.2,
since i don't want to make all your stable users have to deal with
a torrc change. but nickm changed it. is it in fact the case that a
change in that file means a change in the deb?
<weasel> it means you'll prompt every single user who ever touched
their torrc
<weasel> and they will be asked if they like your new version better
than what they have right now
<weasel> so it's not great
Instead I changed the website to redirect requests for the tor-manual
URL listed in maint-0.2.2's torrc.sample.in so the link will still work.
If we don't do this, [::] can be interpreted to mean all v4 and all
v6 addresses. Found by dcf. Fixes bug 4760. See RFC 3493 section
5.3 for more info.
There was one MS_WINDOWS that remained because it wasn't on a macro
line; a few remaining uses (and the definition!) in configure.in;
and a now-nonsensical stanza of eventdns_tor.h that previously
defined 'WIN32' if it didn't exist.
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.
This option seems to be supported all the way back to at least 10.4, so
enabling it for OS X in general should be fine. If not, someone will
yell.
With no libs statically linked, that's a 3% win in binary size, with
just libevent linked statically, this gives us an advantage of 5% in
terms of binary size, and with libevent and openssl statically linked,
we gain over 18% or over 500KB.
Implements ticket 2915.
These were found by looking for tor_snprintf() instances that were
followed closely by tor_strdup(), though I probably converted some
other snprintfs as well.
(To ensure correctness, in every case, make sure that the temporary
variable is deleted, renamed, or lowered in scope, so we can't have
any bugs related to accidentally relying on the no-longer-filled
variable.)
To solve bug 4779, we want to avoid OpenSSL 1.0.0's counter mode.
But Fedora (and maybe others) lie about the actual OpenSSL version,
so we can't trust the header to tell us if it's safe.
Instead, let's do a run-time test to see whether it's safe, and if
not, use our built-in version.
fermenthor contributed a pretty essential fixup to this patch. Thanks!
When we have an effective bandwidthrate configured so that we cannot
exceed our bandwidth limit in one accounting interval, don't disable
advertising the dirport. Implements ticket 2434.
Fixes bug 4413; bugfix on xxxx.
Hostname components cannot be larger than 63 characters.
This simple check makes certain randlen cannot overflow rand_bytes_len.
We used to do this as a workaround for older Tors, but now it's never
the correct thing to do (especially since anything that didn't
understand RELAY_EARLY is now deprecated hard).
This patch should make us reject every Tor that was vulnerable to
CVE-2011-0427. Additionally, it makes us reject every Tor that couldn't
handle RELAY_EARLY cells, which helps with proposal 110 (#4339).
Previously we required 1.0.0, but there was a bug in the 1.0.0 counter
mode. Found by Pascal. Fixes bug 4779.
A more elegant solution would be good here if somebody has time to code
one.
Back in #1240, r1eo linked to information about how this could happen
with older Linux kernels in response to nmap. Bugs #4545 and #4547
are about how our approach to trying to deal with this condition was
broken and stupid. Thanks to wanoskarnet for reminding us about #1240.
This is a fix for the abovementioned bugs, and is a bugfix on
0.1.0.3-rc.
Preprocessor directives should not be put inside the arguments
of a macro. This is not supported on older GCC releases (< 3.3)
thus broke compilation on Haiku (running gcc2).
--enable-gcc-warnings enables two warnings that clang doesn't support,
so the build fails. We had hoped clang 3.0 would add those, but it
didn't, so let's just always disable those warnings when building with
clang. We can still fix it later once they add support
If a relay is dormant at startup, it will call init_keys before
crypto_set_tls_dh_prime. This is bad. Let's make it not so bad, because
someday it *will* happen again.
Conflicts:
src/or/connection_or.c
The conflict in src/or/connection_or.c is resolved by taking the
version in master, since e27a26d5 already fixed bug 4531 on master.
This merge just adds the changes file from 0.2.2.
Some controllers want this so they can mess with Tor's configuration
for a while via the control port before actually letting Tor out of
the house.
We do this with a new DisableNetwork option, that prevents Tor from
making any outbound connections or binding any non-control
listeners. Additionally, it shuts down the same functionality as
shuts down when we are hibernating, plus the code that launches
directory downloads.
To make sure I didn't miss anything, I added a clause straight to
connection_connect, so that we won't even try to open an outbound
socket when the network is disabled. In my testing, I made this an
assert, but since I probably missed something, I've turned it into a
BUG warning for testing.
This will mainly help distributors by giving a way to set system or package
defaults that a user can override, and that a later package can replace.
No promises about the particular future location or semantics for this:
we will probably want to tweak it some before 0.2.3.x-rc
The file is searched for in CONFDIR/torrc-defaults , which can be
overridden with the "--defaults-torrc" option on the command line.
This starts an effort to refactor torrc handling code to make it easier
to live with. It makes it possible to override exit policies from the
command line, and possible to override (rather than append to) socksport
lists from the command line.
It'll be necessary to make a "base" torrc implementation work at all.
This shaves about 7% off our per-cell AES crypto time for me; the
effect for accelerated AES crypto should be even more, since the AES
calculation itself will make an even smaller portion of the
counter-mode performance.
(We don't want to do this for pre-1.0.0 OpenSSL, since our AES_CTR
implementation was actually faster than OpenSSL's there, by about
10%.)
Fixes issue #4526.
The timercmp macro uses triggers a "space between function name and
opening parentheses" warning for the check spaces script. Work around
this by simply disabling the check for all "functions" named 'op()'.
The function is over 10 or 20% on some of Moritz's profiles, depending
on how you could.
Since it's checking for a multi-hour timeout, this is safe to do.
Fixes bug 4518.
Completely disable stats if we aren't running as a relay. We won't
collect any anyway, so setting up the infrastructure for them and
logging about them is wrong. This also removes a confusing log
message that clients without a geoip db would have seen.
Fixes bug 4353.
When running with IOCP, we are in theory able to use userspace-
allocated buffers to avoid filling up the stingy amount of kernel
space allocated for sockets buffers.
The bufferevent_async implementation in Libevent provides this
ability, in theory. (There are likely to be remaining bugs). This
patch adds a new option that, when using IOCP bufferevents, sets
each socket's send and receive buffers to 0, so that we should use
this ability.
When all the bugs are worked out here, if we are right about bug 98,
this might solve or mitigate bug 98.
This option is experimental and will likely require lots of testing
and debugging.
This is a fancier bug4457 workaround for 0.2.3. In 0.2.2, we could
just tell Libevent "Don't enable locking!" so it wouldn't try to make
the event_base notifiable. But for IOCP, we need a notifiable base.
(Eventually, we'll want a notifiable base for other stuff, like
multithreaded crypto.) So the solution is to try a full-featured
initialization, and then retry with all the options turned off if that
fails.
Conflicts:
src/common/compat_libevent.c
Resolving conflict by not taking 7363eae13c ("Use the
EVENT_BASE_FLAG_NOLOCK flag to prevent socketpair() invocation"): in
Tor 0.2.3.x, we _do_ sometimes use notifiable event bases.
In Tor 0.2.2, we never need the event base to be notifiable, since we
don't call it from other threads. This is a workaround for bug 4457,
which is not actually a Tor bug IMO.
This thing was pretty pointless on versions of OpenSSL 0.9.8 and later,
and almost totally pointless on OpenSSL 1.0.0.
Also, favor EVP by default, since it lets us get hardware acceleration
where present. (See issue 4442)
The old behavior was susceptible to the compiler optimizing out our
assertion check, *and* could still overflow size_t on 32-bit systems
even when it did work.
