Thanks to the changes we started making with SocksPort and friends
in 0.2.3.3-alpha, any of our code that did "if (options->Sockport)"
became wrong, since "SocksPort 0" would make that test true whereas
using the default SocksPort value would make it false. (We didn't
actually do "if (options->SockPort)" but we did have tests for
TransPort. When we moved DirPort, ORPort, and ControlPort over to
the same system in 0.2.3.9-alpha, the problem got worse, since our
code is littered with checks for DirPort and ORPort as booleans.
This code renames the current linelist-based FooPort options to
FooPort_lines, and adds new FooPort_set options which get set at
parse-and-validate time on the or_options_t. FooPort_set is true
iff we will actually try to open a listener of the given type. (I
renamed the FooPort options rather than leave them alone so that
every previous user of a FooPort would need to get inspected, and so
that any new code that forgetfully uses FooPort will need fail to
compile.)
Fix for bug 6507.
With this patch, I dump the old kludge of using magic negative
numbers to indicate unknown bandwidths. I also compute each node's
weighted bandwidth exactly once, rather than computing it once in
a loop to compute the total weighted bandwidth and a second time in
a loop to find which one we picked.
Previously, we had incremented rand_bw so that when we later tested
"tmp >= rand_bw", we wouldn't have an off-by-one error. But instead,
it makes more sense to leave rand_bw alone and test "tmp > rand_bw".
Note that this is still safe. To take the example from the bug1203
writeup: Suppose that we have 3 nodes with bandwidth 1. So the
bandwidth array is { 1, 1, 1 }, and the total bandwidth is 3. We
choose rand_bw == 0, 1, or 2. With the first iteration of the loop,
tmp is now 1; with the second, tmp is 2; with the third, tmp is 3.
Now that our check is tmp > rand_bw, we will set i in the first
iteration of the loop iff rand_bw == 0; in the second iteration of
the loop iff rand_bw == 1, and in the third iff rand_bw == 2.
That's what we want.
Incidentally, this change makes the bug 6538 fix more ironclad: once
rand_bw is set to UINT64_MAX, tmp > rand_bw is obviously false
regardless of the value of tmp.
The old approach, because of its "tmp >= rand_bw &&
!i_has_been_chosen" check, would run through the second part of the
loop slightly slower than the first part. Now, we remove
i_has_been_chosen, and instead set rand_bw = UINT64_MAX, so that
every instance of the loop will do exactly the same amount of work
regardless of the initial value of rand_bw.
Fix for bug 6538.
This should make our preferred solution to #6538 easier to
implement, avoid a bunch of potential nastiness with excessive
int-vs-double math, and generally make the code there a little less
scary.
"But wait!" you say. "Is it really safe to do this? Won't the
results come out differently?"
Yes, but not much. We now round every weighted bandwidth to the
nearest byte before computing on it. This will make every node that
had a fractional part of its weighted bandwidth before either
slighty more likely or slightly less likely. Further, the rand_bw
value was only ever set with integer precision, so it can't
accurately sample routers with tiny fractional bandwidth values
anyway. Finally, doing repeated double-vs-uint64 comparisons is
just plain sad; it will involve an implicit cast to double, which is
never a fun thing.
This gives us a few benefits:
1) make -j clean all
this will start working, as it should. It currently doesn't.
2) increased parallel build
recursive make will max out at number of files in a directory,
non-recursive make doesn't have such a limitation
3) Removal of duplicate information in make files,
less error prone
I've also slightly updated how we call AM_INIT_AUTOMAKE, as the way
that was used was not only deprecated but will be *removed* in the next
major automake release (1.13).... so probably best that we can continue
to bulid tor without requiring old automake.
(see http://www.gnu.org/software/automake/manual/html_node/Public-Macros.html )
For more reasons why, see resources such as:
http://miller.emu.id.au/pmiller/books/rmch/
In 0.2.3.18-rc, we started warning on this case while building a
list of missing microdescriptor digests. That turned out to spam
the logs; instead let's warn at parse time.
Partial fix for bug 6404.
The spec requires that every router in a microdesc consensus have an
m line; we weren't obeying that spec.
This creates a new consensus method (13) to allow voting to continue
to work right. Partial fix for bug 6404; fix on 0.2.2.6-alpha.
Test for config option AuthDirPublishIPv6 == 1 rather than for running
as a bridge authority when deciding whether to care or not about IPv6
OR ports in descriptors.
Implements enhancement #6406.
We can end up in dirserv_orconn_tls_done() with a node missing
routerinfo in at least two cases -- command_process_certs_cell() and
connection_or_check_valid_tls_handshake() -- and probably more.
You can say "struct foo_t" as much as you want, but you'd better not
have "typedef struct foo_t foo_t" more than once.
Fix for bug 6416. Bug not in any released version of Tor.
This avoids a possible crash bug in flush_from_first_active_circuit.
Fixes bug 6341; bugfix on 0.2.2.7-alpha.
Bug reported and fixed by a pseudonymous user on IRC.
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.
The SMARTLIST_FOREACH macro is more convenient than BEGIN/END when
you have a nice short loop body, but using it for long bodies makes
your preprocessor tell the compiler that all the code is on the same
line. That causes grief, since compiler warnings and debugger lines
will all refer to that one line.
So, here's a new style rule: SMARTLIST_FOREACH blocks need to be
short.
- 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.
We were doing a tor_strclear() on client_keys_str when it might not
even be set.
Fix for bug 6255; bug not in any release of Tor. Thanks to katmagic
for finding this one!
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.
We now catch bare {s that should be on the previous line with a do,
while, if, or for, and elses that should share a line with their
preceding }.
That is,
if (foo)
{
and
if (foo) {
...
}
else
are now detected.
We should think about maybe making Tor uncrustify-clean some day,
but configuring uncrustify is an exercise in bizarreness, and
reformatting huge gobs of Tor is always painful.
We can treat this case as an EAGAIN (probably because of an
unexpected internal NUL) rather than a crash-worthy problem.
Fixes bug 6225, again. Bug not in any released version of Tor.
Because the string output was no longer equal in length to
HEX_ERRNO_SIZE, the write() call would add some extra spaces and
maybe a NUL, and the NUL would trigger an assert in
get_string_from_pipe.
Fixes bug 6225; bug not in any released version of Tor.
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.
Now it's an orthodox "goto err/done" exit path, and it isn't some
screwy thing where we stick err/done at the end of a loop and
duplicate our cleanup code.
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.
I saw 72% on a test run with 26 circuits. 70% might be a little close to the
line. That, or min_circs is too low and we need to be more patient. We still
need to test/simulate more.
The defense counts the circuit failure rate for each guard for the past N
circuits. Failure is defined as the ability to complete a first hop, but not
finish completing the circuit all the way to the exit.
If the failure rate exceeds a certain amount, a notice is emitted.
If it exceeds a greater amount, a warn is emitted and the guard is disabled.
These values are governed by consensus parameters which we intend to tune as
we perform experiments and statistical simulations.
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.
There is a bug causing busy loops in Libevent and infinite loops in
the Shadow simulator. A connection that is marked for close, wants
to flush, is held open to flush, but is rate limited (the token
bucket is empty) triggers the bug.
This commit fixes the bug. Details are below.
This currently happens on read and write callbacks when the active
socket is marked for close. In this case, Tor doesn't actually try
to complete the read or write (it returns from those methods when
marked), but instead tries to clear the connection with
conn_close_if_marked(). Tor will not close a marked connection that
contains data: it must be flushed first. The bug occurs when this
flush operation on the marked connection can not occur because the
connection is rate-limited (its write token bucket is empty).
The fix is to detect when rate limiting is preventing a marked
connection from properly flushing. In this case, it should be
flagged as read/write_blocked_on_bandwidth and the read/write events
de-registered from Libevent. When the token bucket gets refilled, it
will check the associated read/write_blocked_on_bandwidth flag, and
add the read/write event back to Libevent, which will cause it to
fire. This time, it will be properly flushed and closed.
The reason that both read and write events are both de-registered
when the marked connection can not flush is because both result in
the same behavior. Both read/write events on marked connections will
never again do any actual reads/writes, and are only useful to
trigger the flush and close the connection. By setting the
associated read/write_blocked_on_bandwidth flag, we ensure that the
event will get added back to Libevent, properly flushed, and closed.
Why is this important? Every Shadow event occurs at a discrete time
instant. If Tor does not properly deregister Libevent events that
fire but result in Tor essentially doing nothing, Libevent will
repeatedly fire the event. In Shadow this means infinite loop,
outside of Shadow this means wasted CPU cycles.
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 include:
- Having a weird in_addr that can't be initialized with {0}
- Needing INVALID_HANDLE_VALUE instead of -1 for file handles.
- Having a weird dependent definition for struct stat.
- pid is signed, not unsigned.
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.
