When looking up an entry in the rend_cache, stop asserting that it exists but
rather confirm it exists and if not, return that no entry was found.
The reason for that is because the hs_circ_cleanup_on_free() function (which
can end up looking at the rend_cache) can be called from the
circuit_free_all() function that is called _after_ the rend cache is cleaned
up in tor_free_all().
We could fix the free all ordering but then it will just hide a future bug.
Instead, handle a missing rend_cache as a valid use case as in while we are in
the cleanup process.
As Tor becomes more modular, it is getting more and more difficult to ensure
subsystem callstack ordering thus this fix aims at making the HSv2 subsystem
more robust at being called while tor is pretty much in any kind of state.
Fixes#32847.
Signed-off-by: David Goulet <dgoulet@torproject.org>
All of these files contain "*.h", except for:
* src/app/config/.may_include
* src/test/.may_include
which also contain "*.inc".
This change prevents includes of "*.c" files, and other
unusually named files.
Part of 32609.
By centralizing the circuit cleanup type that is: on close, free and
repurpose, some actions on the circuit can not happen for a certain cleanup
type or for all types.
This passes a cleanup type so the HS subsystem (v2 and v3) can take actions
based on the type of cleanup.
For instance, there is slow code that we do not run on a circuit close but
rather only on free.
Part of #32020
Signed-off-by: David Goulet <dgoulet@torproject.org>
Old and messy code path. Structure it in a more pleasant and readable way. No
behavior change with this refactor.
Part of #32020
Signed-off-by: David Goulet <dgoulet@torproject.org>
Refactor to decomplexify circuit_about_to_free() and finally have one single
entry point into the HS subsystems (v2 and v3) for when a circuit is freed.
With this, hs_circ_cleanup() becomes the one and only entry point when a
circuit is freed which then routes to the right subsystem version for any
actions to be taken.
This moves a big chunk of code from circuituse.c to rendclient.c. No behavior
change. Next commit will refactor it to reduce our technical debt.
Part of #32020
Signed-off-by: David Goulet <dgoulet@torproject.org>
Using a standard ending here will let other tools that expect
markdown understand our output here.
This commit was automatically generated with:
for fn in $(find src -name '*.dox'); do \
git mv "$fn" "${fn%.dox}.md"; \
done
This includes app, core, feature, lib, and tools, but excludes
ext, test, and trunnel.
This was generated by the following shell script:
cd src
for dname in $(find lib core feature app tools -type d |grep -v \\.deps$); do
keyword="$(echo "$dname" |sed -e "s/\//_/" )"
target="${dname}/${keyword}.dox"
echo "$target"
cat <<EOF >"$target"
/**
@dir ${dname}
@brief ${dname}
**/
EOF
git add "$target"
done
When picking an intro point from the service descriptor, the client failed to
lookup the failure cache.
It made an HS v2 client re-pick bad intro points for which we already know it
won't work in the first place.
Based on Neel Chauhan original patch.
Fixes#25568
Signed-off-by: David Goulet <dgoulet@torproject.org>
A bit cleaner especially that the next commit(s) will make the consensus param
interface private to hs_dos.c so we expose as little as we can outside of the
subsystem.
Part of #30924
Signed-off-by: David Goulet <dgoulet@torproject.org>
This commit add the hs_dos.{c|h} file that has the purpose of having the
anti-DoS code for onion services.
At this commit, it only has one which is a function that decides if an
INTRODUCE2 can be sent on the given introduction service circuit (S<->IP)
using a simple token bucket.
The rate per second is 25 and allowed burst to 200.
Basic defenses on #15516.
Signed-off-by: David Goulet <dgoulet@torproject.org>
When we repurpose a hidden service circuit, we need to clean up from the HS
circuit map and any HS related data structured contained in the circuit.
This commit adds an helper function that does it when repurposing a hidden
service circuit.
Fixes#29034
Signed-off-by: David Goulet <dgoulet@torproject.org>
Some of these functions are now public and cpath-specific so their name should
signify the fact they are part of the cpath module:
assert_cpath_layer_ok -> cpath_assert_layer_ok
assert_cpath_ok -> cpath_assert_ok
onion_append_hop -> cpath_append_hop
circuit_init_cpath_crypto -> cpath_init_circuit_crypto
circuit_free_cpath_node -> cpath_free
onion_append_to_cpath -> cpath_extend_linked_list
We are using an opaque pointer so the structure needs to be allocated on the
heap. This means we now need a constructor for crypt_path_t.
Also modify all places initializing a crypt_path_t to use the constructor.
I don't believe any of these represent a real timing vulnerability
(remote timing against memcmp() on a modern CPU is not easy), but
these are the ones where I believe we should be more careful.