Tor stores client authorization cookies in two slightly different forms.
The service's client_keys file has the standard base64-encoded cookie,
including two chars of padding. The hostname file and the client remove
the two padding chars, and store an auth type flag in the unused bits.
The distinction makes no sense. Refactor all decoding to use the same
function, which will accept either form, and use a helper function for
encoding the truncated format.
When an HS process an INTRODUCE2 cell, we didn't validate if the IP address
of the rendezvous point was a local address. If it's the case, we end up
wasting resources by trying to extend to a local address which fails since
we do not allow that in circuit_extend().
This commit now rejects a rendezvous point that has a local address once
seen at the hidden service side unless ExtendAllowPrivateAddresses is set.
Fixes#8976
Signed-off-by: David Goulet <dgoulet@ev0ke.net>
The wrong list was used when looking up expired intro points in a rend
service object causing what we think could be reachability issues and
triggering a BUG log.
Fixes#16702
Signed-off-by: David Goulet <dgoulet@ev0ke.net>
Removes a check to PublishHidServDescriptors in
rend_consider_services_upload(). This allows descriptors to be
generated and stored in the local cache when PublishHidServDescriptor = 0.
Keep the PublishHidServDescriptors option check in
rend_consider_descriptor_republication(). We will never need to republish
a descriptor if we are not publishing descriptors to the HSDirs.
Service descriptors are now generated regardless of the the
PublishHidServDescriptors option. The generated descriptors are stored
in the service descriptor cache.
The PublishHidServDescriptors = 1 option now prevents descriptor
publication to the HSDirs rather than descriptor generation.
Deindent a block of code inside the PublishHidServDescriptors option
check in upload_service_descriptor(). Stylistic commit to make the
subsequent reworking of this code cleaner.
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.
Signed-off-by: David Goulet <dgoulet@ev0ke.net>
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.
This partially fixes#13483.
Signed-off-by: David Goulet <dgoulet@ev0ke.net>
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.
Fixes#8239
Signed-off-by: David Goulet <dgoulet@ev0ke.net>
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.
Fixes#8864
Signed-off-by: David Goulet <dgoulet@ev0ke.net>
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>
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.
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.
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.
Every callsite that use to allocate a rend_data_t object now use the
rend_data_client/service_create() function.
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.
Incidently, this fixes a bug where the maximum value was never used when
only using crypto_rand_int(). For instance this example below in
rendservice.c never gets to INTRO_POINT_LIFETIME_MAX_SECONDS.
int intro_point_lifetime_seconds =
INTRO_POINT_LIFETIME_MIN_SECONDS +
crypto_rand_int(INTRO_POINT_LIFETIME_MAX_SECONDS -
INTRO_POINT_LIFETIME_MIN_SECONDS);
Signed-off-by: David Goulet <dgoulet@ev0ke.net>
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>
In #14803, Damian noticed that his Tor sometimes segfaults. Roger noted
that his valgrind gave an invalid write of size one here. Whenever we
use FLEXIBLE_ARRAY_MEMBER, we have to make sure to actually malloc a
thing that's large enough.
Fixes bug #14803, not in any released version of Tor.
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.
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.
We had some code to fix up the 'status' return value to -1 on error
if it wasn't set, but it was unreachable because our code was
correct. Tweak this by initializing status to -1, and then only
setting it to 0 on success. Also add a goto which was missing: its
absence was harmless.
[CID 718614, 718616]
(We allowed it previously, but produced an LD_BUG message when it
happened, which is not consistent
Also, remove inconsistent NULL checks before calling
rend_service_intro_free.
(Removing the check is for CID 718613)
If 'intro' is NULL in these functions, I'm pretty sure that the
error message must be set before we hit the end. But scan-build
doesn't notice that, and is worried that we'll do a null-pointer
dereference in the last-chance errormsg generation.
Fortunately, later checks mean that uninitialized data can't get sent
to the network by this bug. Unfortunately, reading uninitialized heap
*can* (in some cases, with some allocators) cause a crash if you get
unlucky and go off the end of a page.
Found by asn. Bugfix on 0.2.4.1-alpha.
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.
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.
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;
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 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;
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..
Apparently some compilers like to eliminate memset() operations on
data that's about to go out-of-scope. I've gone with the safest
possible replacement, which might be a bit slow. I don't think this
is critical path in any way that will affect performance, but if it
is, we can work on that in 0.2.4.
Fixes bug 7352.
This is mostly a conversion from this pattern:
log("... %s:%d ...", fmt_and_decorate_addr(&addr), port);
to this:
log("... %s ...", fmt_addrport(&addr, port));
The output is the same in all cases.
When I removed version_supports_begindir, I accidentally removed the
mechanism we had been using to make a directory cache self-test its
directory port. This caused bug 6815, which caused 6814 (both in
0.2.4.2-alpha).
To fix this bug, I'm replacing the "anonymized_connection" argument to
directory_initiate_command_* with an enumeration to say how indirectly
to connect to a directory server. (I don't want to reinstate the
"version_supports_begindir" argument as "begindir_ok" or anything --
these functions already take too many arguments.)
For safety, I made sure that passing 0 and 1 for 'indirection' gives
the same result as you would have gotten before -- just in case I
missed any 0s or 1s.
There was some code in the "err:" block that would always log a
warning, reporting an "unknown error" if we hadn't set err_msg. But
there were also plenty of "goto err" blocks that did their own
logging, and never set err_msg at all. Now we should only log when
we have an error message to log.
This fixes bug 6638, from no released Tor version.
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!
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.
