David Goulet [Thu, 30 Jul 2015 18:43:15 +0000 (14:43 -0400)]
Add get_max_sockets() and remove dead code
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.
Allow a single trailing `.` when validating FQDNs from SOCKS.
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.
The only reason 16 byte alignment is required is for SSE2 load and
store operations, so only align datastructures to 16 byte boundaries
when building with SSE2 support.
This fixes builds with GCC SSP on platforms that don't have special
case code to do dynamic stack re-alignment (everything not x86/x86_64).
The workqueue test help message has two issues. First, the message uses 4 space
indentation when 2 space indentation seems more common. Second, the help
message misses some options.
Nick Mathewson [Tue, 14 Jul 2015 15:27:49 +0000 (11:27 -0400)]
Add more consistency checks in load_ed_keys
Make sure that signing certs are signed by the right identity key,
to prevent a recurrence of #16530. Also make sure that the master
identity key we find on disk matches the one we have in RAM, if we
have one.
David Goulet [Mon, 15 Jun 2015 21:11:57 +0000 (17:11 -0400)]
Count intro circuit and not only established ones
When cleaning up extra circuits that we've opened for performance reason, we
need to count all the introduction circuit and not only the established ones
else we can end up with too many introduction points.
This also adds the check for expiring nodes when serving an INTRODUCE cell
since it's possible old clients are still using them before we have time to
close them.
David Goulet [Mon, 1 Jun 2015 17:17:37 +0000 (13:17 -0400)]
Upload descriptor when all intro points are ready
To upload a HS descriptor, this commits makes it that we wait for all
introduction point to be fully established.
Else, the HS ends up uploading a descriptor that may contain intro points
that are not yet "valid" meaning not yet established or proven to work. It
could also trigger three uploads for the *same* descriptor if every intro
points takes more than 30 seconds to establish because of desc_is_dirty
being set at each intro established.
To achieve that, n_intro_points_established varialbe is added to the
rend_service_t object that is incremented when we established introduction
point and decremented when we remove a valid intro point from our list.
The condition to upload a descriptor also changes to test if all intro
points are ready by making sure we have equal or more wanted intro points
that are ready.
The desc_id_dirty flag is kept to be able to still use the
RendInitialPostPeriod option.
David Goulet [Mon, 1 Jun 2015 16:08:13 +0000 (12:08 -0400)]
Reuse intro points that failed but are still valid
There is a case where if the introduction circuit fails but the node is
still in the consensus, we clean up the intro point and choose an other one.
This commit fixes that by trying to reuse the existing intro point with a
maximum value of retry.
A retry_nodes list is added to rend_services_introduce() and when we remove
an invalid intro points that fits the use case mentionned before, we add the
node to the retry list instead of removing it. Then, we retry on them before
creating new ones.
This means that the requirement to remove an intro point changes from "if no
intro circuit" to "if no intro circuit then if no node OR we've reached our
maximum circuit creation count".
For now, the maximum retries is set to 3 which it completely arbitrary. It
should also at some point be tied to the work done on detecting if our
network is down or not.
David Goulet [Fri, 29 May 2015 21:45:45 +0000 (17:45 -0400)]
Refactor rend_services_introduce()
The reasoning for refactoring this function is that removing the
introduction point adaptative algorithm (#4862) ended up changing quite a
bit rend_services_introduce(). Also, to fix some open issues (#8239, #8864
and #13483), this work had to be done.
First, this removes time_expiring variable in an intro point object and
INTRO_POINT_EXPIRATION_GRACE_PERIOD trickery and use an expiring_nodes list
where intro nodes that should expire are moved to that list and cleaned up
only once the new descriptor is successfully uploaded. The previous scheme
was adding complexity and arbitrary timing to when we expire an intro point.
We keep the intro points until we are sure that the new descriptor is
uploaded and thus ready to be used by clients. For this,
rend_service_desc_has_uploaded() is added to notify the HS subsystem that
the descriptor has been successfully uploaded. The purpose of this function
is to cleanup the expiring nodes and circuits if any.
Secondly, this adds the remove_invalid_intro_points() function in order to
split up rend_services_introduce() a bit with an extra modification to it
that fixes #8864. We do NOT close the circuit nor delete the intro point if
the circuit is still alive but the node was removed from the consensus. Due
to possible information leak, we let the circuit and intro point object
expire instead.
Finally, the whole code flow is simplified and large amount of documentation
has been added to mostly explain the why of things in there.
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.
Integrate the accelerated Curve25519 scalar basemult.
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.
Add Curve25519->Ed25519 support to ed25519-donna (Not yet used).
This needs to be done to allow for the possibility of removing the
ref10 code at a later date, though it is not performance critical.
When integrated by kludging it into tor, it passes unit tests, and is
twice as fast.