We now keep descriptor that we can't decode due to missing client
authorization in the cache.
This new function is used when new client authorization are added and to tell
the client cache to retry decoding.
Part of #30382
Signed-off-by: David Goulet <dgoulet@torproject.org>
This commit extract most of the code that dirclient.c had to handle the end of
a descriptor directory requests (fetch). It is moved into hs_client.c in order
to have one single point of entry and the rest is fully handled by the HS
subsystem.
As part of #30382, depending on how the descriptor ended up stored (decoded or
not), different SOCKS error code can be returned.
Signed-off-by: David Goulet <dgoulet@torproject.org>
This will allow us to callback into the HS subsytem depending on the decoding
status and return an extended SOCKS5 error code depending on the decoding
issue.
This is how we'll be able to tell the SocksPort connection if we are missing
or have bad client authorization for a service.
Part of #30382
Signed-off-by: David Goulet <dgoulet@torproject.org>
We now keep the descriptor in the cache, obviously not decoded, if it can't be
decrypted for which we believe client authorization is missing or unusable
(bad).
This way, it can be used later once the client authorization are added or
updated.
Part of #30382
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
In our old design, we had to declare configuration structures (like
or_options_t) and variable tables (like option_vars_) separately,
and we used some magic to enforce their consistency (see
conftesting.h).
With this design, we write a single definition for the configuration
object and its fields, and use C macros to expand it either into a
structure, or a variable table. Since they are both made from the
same source, they can't become inconsistent.
The two designs can coexist happily, and we can migrate from one to
the other at our convenience.
When the relay module is disabled, make "ClientOnly 1" and
"DirCache 0" by default. (But keep "ClientOnly 0" and
"DirCache 1" as the defaults for the unit tests.)
And run "make autostyle".
Part of ticket 32410.
This is an automated commit, generated by this command:
./scripts/maint/rename_c_identifier.py \
get_dirportfrontpage relay_get_dirportfrontpage \
parse_port_config port_parse_config \
count_real_listeners port_count_real_listeners \
parse_transport_line pt_parse_transport_line \
ensure_bandwidth_cap config_ensure_bandwidth_cap \
get_effective_bwrate relay_get_effective_bwrate \
get_effective_bwburst relay_get_effective_bwburst \
warn_nonlocal_ext_orports port_warn_nonlocal_ext_orports \
parse_ports_relay port_parse_ports_relay \
update_port_set_relay port_update_port_set_relay \
get_transport_bindaddr_from_config pt_get_bindaddr_from_config \
get_options_for_server_transport pt_get_options_for_server_transport
It was generated with --no-verify, because it has some long lines.
Part of 32213.
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
This commit:
* disables the ExtORPort, ServerTransportPlugin,
ServerTransportListenAddress, and ServerTransportOptions options,
when the relay module is disabled.
Part of 32213.
This commit:
* disables the ORPort, DirPort, DirCache, and BridgeRelay options,
* sets ClientOnly 1,
* disables relay_config.c and relay/transport_config.c,
* disables test_rebind.sh, and
* modifies the expected results for test_parseconf.sh,
when the relay module is disabled.
Part of 32213.
Minor simplification and refactoring.
Make the dirauth tests focus on testing the intention of the code,
rather than option processing order.
Part of 32213.
The DoS heartbeat now contains the number of rejected INTRODUCE2 cell that the
relay has seen.
Closes#31371
Signed-off-by: David Goulet <dgoulet@torproject.org>
This required a small refactoring so we could count properly the INTRO2
sending disallow.
Part of #31371
Signed-off-by: David Goulet <dgoulet@torproject.org>
This commit:
* moves dirauth stats and mtbf config actions into dirauth_config,
* adds thin wrappers to make the moved code compile.
The moved code is disabled when the dirauth module is disabled.
Part of 32213.
This commit:
* moves relay config actions into relay_config,
* moves get_dirportfrontpage() into relay_config,
* adds thin wrappers to make the moved code compile.
No functional changes: the moved code is still enabled,
even if the relay module is disabled. (Some of the checks
are re-ordered, so the order of some warnings may change.)
Part of 32213.
This commit:
* moves server transport config checks into transport_config.c,
* adds thin wrappers to make the moved code compile.
No functional changes: the moved code is still enabled,
even if the relay module is disabled. (Some of the checks
are re-ordered, so the order of some warnings may change.)
Part of 32213.
This commit:
* moves bandwidth checks into dirauth_config, and
* moves some other minor checks into dirauth_config.
The moved code is disabled when the dirauth module is disabled.
(And some of the checks are re-ordered, so the order of some
warnings may change.)
Part of 32213.
This commit:
* moves accounting and bandwidth checks into relay_config,
* moves testing options checks into relay_config,
* moves some other minor checks into relay_config,
* exposes some code from src/app/config.c
(we'll refactor it later in 29211), and
* adds thin wrappers to make the moved code compile.
No functional changes: the moved code is still enabled,
even if the relay module is disabled. (Some of the checks
are re-ordered, so the order of some warnings may change.)
Part of 32213.
This commit:
* creates feature/relay/transport_config.[ch],
* moves server transport config checks into them,
* exposes some code from src/app/config.c
(we'll refactor it later in 29211), and
* adds thin wrappers to make the moved code compile.
No functional changes: the moved code is still enabled,
even if the relay module is disabled. (Some of the checks
are re-ordered, so the order of some warnings may change.)
Part of 32213.
This commit:
* moves relay config checks into relay_config.[ch],
* exposes some code from src/app/config.c
(we'll refactor it later in 29211), and
* adds thin wrappers to make the moved code compile.
No functional changes: the moved code is still enabled,
even if the relay module is disabled. (Some of the checks
are re-ordered, so the order of some warnings may change.)
Part of 32213.
This commit:
* creates feature/relay/relay_config.[ch],
* moves relay port parsing into them,
* exposes some code from src/app/config.c
(we'll refactor it later in 29211), and
* adds thin wrappers to make the moved code compile.
No functional changes: the moved code is still enabled,
even if the relay module is disabled.
Part of 32213.
This commit:
* creates feature/dirauth/dirauth_config.[ch],
* moves the dirauth config code into them,
* copies some macros from src/app/config.c
(we'll refactor them later in 29211), and
* adds thin wrappers to make the moved code compile.
No functional changes: the moved code is still enabled,
even if the dirauth module is disabled.
Part of 32213.
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>
This is an automated commit, generated by this command:
./scripts/maint/rename_c_identifier.py \
confparse.h confmgt.h \
confparse.c confmgt.c \
CONFPARSE_PRIVATE CONFMGT_PRIVATE \
TOR_CONFPARSE_H TOR_CONFMGT_H
The former foo_validate() functions are now toplevel
legacy_validate_fn callbacks. The new foo_validate() functions now
call them.
This change lets us remove the old shared_random disk state
validation callback entirely.
The current API of this callback mixes responsibilities, including:
* validation
* transition checking
* processing (modifying) the configuration object.
These will have to be disentangled piece by piece, so for now, we'll
have "legacy" validate functions as well.
This is an automated commit, generated by this command:
./scripts/maint/rename_c_identifier.py \
validate_fn_t legacy_validate_fn_t \
validate_fn legacy_validate_fn
Single hop rejection (POST and GET) for HS v3 descriptor now return a 503 code
which is more accurate code from dir-spec.txt and from other rejection case in
the code.
For instance if you are not a relay and you get a POST request, a 503 code is
sent back with a rejection message.
Part of #31958
Signed-off-by: David Goulet <dgoulet@torproject.org>
First, remove the HSDir mention which should not be in that generic function.
Second, move them to debug() level since they are possible error case.
Part of #31958
Signed-off-by: David Goulet <dgoulet@torproject.org>
Before inspecting the p_chan, we must check if the circuit is marked for close
because if it is the case, the channels are nullified from the circuit.
Several valid cases can mark the circuit for close of the directory
connection.
Fixes#31958
Signed-off-by: David Goulet <dgoulet@torproject.org>
hs_client_purge_state() and hs_cache_clean_as_client() can remove a descriptor
from the client cache with a NEWNYM or simply when the descriptor expires.
Which means that for an INTRO circuit being established during that time, once
it opens, we lookup the descriptor to get the IP object but hey surprised, no
more descriptor.
The approach here is minimalist that is accept the race and close the circuit
since we can not continue. Before that, the circuit would stay opened and the
client wait the SockTimeout.
Fixers #28970.
Signed-off-by: David Goulet <dgoulet@torproject.org>
Only use the HS circuit map to know if an introduction circuit is established
or not. No need for a flag to keep state of something we already have in the
circuit map. Furthermore, the circuit map gets cleaned up properly so it will
always have the "latest truth".
This commit also removes a unit test that was testing specifically that flag
but now we rely solely on the HS circuit map which is also tested few lines
below the removed test.
Fixes#32094
Signed-off-by: David Goulet <dgoulet@torproject.org>
Our minimum version is now 0.2.9.5-alpha. Series 0.3.0, 0.3.1,
0.3.2, 0.3.3, and 0.3.4 are now rejected.
Also, extract this version-checking code into a new function, so we
can test it.
Closes ticket 31549.
Also reject 0.3.5.0 through 0.3.5.6-rc as unstable.
Conflicts:
src/feature/dirparse/authcert_parse.c
src/feature/dirparse/ns_parse.c
src/feature/hs/hs_service.c
src/lib/conf/conftesting.h
src/lib/log/log.h
src/lib/thread/threads.h
src/test/test_options.c
These conflicts were mostly related to autostyle improvements, with
one or two due to doxygen fixes.
This patch removes an overly strict tor_assert() and an ignorable BUG()
expression. Both of these would trigger if a PT was unable to configure
itself during startup. The easy way to trigger this is to configure an
obfs4 bridge where you make the obfs4 process try to bind on a port
number under 1024.
See: https://bugs.torproject.org/31091
This commit introduces the hs_desc_decode_status_t enum which aims at having
more fine grained error code when decoding a descriptor.
This will be useful in later commits when we support keeping a descriptor that
can't be decrypted due to missing or bad client authorization creds.
No behavior change.
Part of #30382.
Signed-off-by: David Goulet <dgoulet@torproject.org>
No code behavior change. This removes duplicate code that was finding all
entry connections for a specific onion service identity key.
The find_entry_conns() helper function is introduced for that.
Part of #30382
Signed-off-by: David Goulet <dgoulet@torproject.org>
Because we need to construct the URI using the TCPProxy configuration
but we don't have a standard URI scheme for haproxy yet, we decided to
not support TCPProxy in TOR_PT_PROXY now. There is no problem with
HTTPSProxy, Socks4Proxy, or Socks5Proxy because they all have standard
URI schemes.
In case of error, a negative value will be returned or NULL written into
first supplied argument.
This patch uses both cases to comply with style in the specific files.
A tor_vasprintf error in process_vprintf would lead to a NULL dereference
later on in buf_add, because the return value -1 casted to size_t would
pass an assertion check inside of buf_add.
On the other hand, common systems will fail on such an operation, so it
is not a huge difference to a simple assertion. Yet it is better to
properly fail instead of relying on such behaviour on all systems.
Signed-off-by: Tobias Stoeckmann <tobias@stoeckmann.org>
Found by coverity CID 1454769.
There were a second possible leak that is also fixed in this commit.
Fixes#32063
Signed-off-by: David Goulet <dgoulet@torproject.org>
When considering introduction point of a service's descriptor, do not remove
an intro point that has an established or pending circuit.
Fixes#31652
Signed-off-by: David Goulet <dgoulet@torproject.org>
When encoding introduction points, we were not checking if that intro points
had an established circuit.
When botting up, the service will pick, by default, 3 + 2 intro points and the
first 3 that establish, we use them and upload the descriptor.
However, the intro point is removed from the service descriptor list only when
the circuit has opened and we see that we have already enough intro points, it
is then removed.
But it is possible that the service establishes 3 intro points successfully
before the other(s) have even opened yet.
This lead to the service encoding extra intro points in the descriptor even
though the circuit is not opened or might never establish (#31561).
Fixes#31548
Signed-off-by: David Goulet <dgoulet@torproject.org>
Our minimum version is now 0.2.9.5-alpha. Series 0.3.0, 0.3.1,
0.3.2, 0.3.3, and 0.3.4 are now rejected.
Also, extract this version-checking code into a new function, so we
can test it.
Closes ticket 31549.
Also reject 0.3.5.0 through 0.3.5.6-rc as unstable.
There is a bad design choice in two of our configuration types,
where the empty string encodes a value that is not the same as the
default value. This design choice, plus an implementation mistake,
meant that config_dup() did not preserve the value of routerset_t,
and thereby caused bug #31495.
This comment-only patch documents the two types with the problem,
and suggests that implementors try to avoid it in the future.
Closes ticket 31907.
- The function `decrypt_desc_layer` has a cleaner interface.
- `is_superencrypted_layer` changed from `int` -> `bool`
[ticket details](https://trac.torproject.org/projects/tor/ticket/31589)
add(changes/*): changes file
fix(src/features/hs): is_superencrypted changed from `int` -> `bool`
fix(changes/ticket31589): header
add(changes/ticket31589): subsystem(onion services) to change
The code here parses the fields from the microdescriptor, including
possible annotations, and stores them into a microdesc_t object.
This commit is almost pure code movement; I recommend using
--color-moved to review it.
This code is logically independent of the rest of the function, and
goes better in its own function.
This is almost purely code movement; I suggest reviewing with
--color-moved.
Our dimap code asserts if you try to add the same key twice; this
can't happen if everything is running smoothly, but it's possible if
you try to start a relay where secret_onion_key_ntor is the same as
secret_onion_key_ntor.old.
Fixes bug 30916; bugfix on 0.2.4.8-alpha when ntor keys were
introduced.
We have code in microdescs_parse_from_string() to record the digests
of microdescriptors that we could not parse. But right now, that
code looks at the md->digest field, which is a bit inelegant, and
will stand in the way of sensible refactoring.
Instead, use a local variable to hold the digest.
When tor is missing descriptors for some primary entry guards, make the
log message less alarming. It's normal for descriptors to expire, as long
as tor fetches new ones soon after.
Fixes bug 31657; bugfix on 0.3.3.1-alpha.
This fixes LTO compilation for Android and -O0 compilation in
general, when --disable-module-dirauth is provided.
Fixes bug 31552; bugfix on 0.4.1.1-alpha.
Rewrite format_node_description() and router_get_verbose_nickname() to
use strlcpy() and strlcat(). The previous implementation used memcpy()
and pointer arithmetic, which was error-prone.
Closes ticket 31545. This is CID 1452819.
These functions are all used to implement the ROUTERSET_type_defn
object, which maps strings to and from routerset_t configuration
variables for the configuration module.
routerset_t has two representations of an empty routerset: NULL, and
a set containing no elements. But some of our config code assumes
that empty routersets are represented as NULL. So let's give it
what it assumes.
Fixes bug 31495. Bugfix on e16b90b88a76; but not in any released
Tor.
The right way to free a config object is now to wrap config_free(),
always. Instead of creating an alternative free function, objects
should provide an alternative clear callback to free any fields that
the configuration manager doesn't manage.
This lets us simplify our code a little, and lets us extend the
confparse.c code to manage additional fields in config_free.
Move everything to its own function in order to better log, document and tests
the introduction point validation process.
Signed-off-by: David Goulet <dgoulet@torproject.org>
When consensus changes, we also need to update the circuit INTRO2 defenses
enabled flag and not only the token bucket.
Signed-off-by: David Goulet <dgoulet@torproject.org>
Remove the public functions returning the HS DoS consensus param or default
values as it is exclusively used internally now.
Rename the param_* variables to consensus_param_* for better code semantic.
Finally, make some private functions available to unit tests.
Signed-off-by: David Goulet <dgoulet@torproject.org>
This commit makes it that the hs_dos.c file only uses the consensus parameter
variables set when we initialize and when the consensus changes.
There is no need to call each time networkstatus_get_param(), which is
expensive, when we want access to a consensus value.
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 makes tor add the DoS cell extension to the ESTABLISH_INTRO cell
if the defense is enabled on the service side with a torrc option.
Furthermore, the cell extension is only added if the introduction point
supports it. The protover version HSIntro=5 is looked for.
Signed-off-by: David Goulet <dgoulet@torproject.org>
Make it clear that these functions return the consensus param only.
Introduction point can not set those values with a torrc option.
Signed-off-by: David Goulet <dgoulet@torproject.org>
Previously, v3 single onion services failed when all intro nodes were
unreachable via a 1-hop path. Now, we select intros that are only available
via a 3-hop path, and use a 3-hop path to connect to them.
Fixes bug 23507; bugfix on 0.3.2.1-alpha.
Previously, we used a 1-hop path when a single onion rend failed
immediately, and a 3-hop path when it failed after trying to build
a circuit.
Fixes bug 23818; bugfix on 0.3.2.1-alpha.
In case the consensus parameters for the rate/burst changes, we need to update
all already established introduction circuits to the newest value.
This commit introduces a "get all intro circ" function from the HS circuitmap
(v2 and v3) so it can be used by the HS DoS module to go over all circuits and
adjust the INTRODUCE2 token bucket parameters.
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>
Now that we have a reasonable implementation for overriding the
default options for TestingTorNetwork, we don't need to modify
config_var_t structs any more. And therefore, we can have constant
format options, like reasonable people.
It's important to make sure that we don't change a config_mgr_t
after we start using it to make objects, or we could get into
inconsistent states. This feature is the start of a safety
mechanism to prevent this problem.
Remember that our goal in the present refactoring is to allow each
subsystem to declare its own configuration structure and
variables. To do this, each module will get its own
config_format_t, and so we'll want a different structure that wraps
several config_format_t objects. This is a "config_mgr_t".
This shouldn't be possible while Tor is running, but the tests can
hit this code. Rather than force the tests to add a dummy channel
object, let's just tolerate their incompletely built circuits.
There is other code that uses this value, and some of it is
apparently reachable from inside router_dir_info_changed(), which
routerlist_free() apparently calls. (ouch!) This is a minimal fix
to try to resolve the issue without causing other problems.
Fixes bug 31003. I'm calling this a bugfix on 0.1.2.2-alpha, where
the call to router_dir_info_changed() was added to routerlist_free().
Fix add_onion_helper_clientauth() and add_onion_helper_keyarg() to
explicitly call the appropriate control reply abstractions instead of
allocating a string to pass to their callers.
Part of ticket 30889.
Always publish bridge pluggable transport information in the extra info
descriptor, even if ExtraInfoStatistics is 0. This information is
needed by BridgeDB.
Fixes bug 30956; bugfix on 0.4.1.1-alpha.
This will effectively also deny any bridge to be used as a single hop to the
introduction point since bridge do not authenticate like clients.
Fixes#24963
Signed-off-by: David Goulet <dgoulet@torproject.org>
When we consider all circuits in "waiting for guard" state to be promoted to
an "open" state, we were considering all circuits, even the one marked for
close.
This ultiamtely triggers a "circuit_has_opened()" called on the circuit that
is marked for close which then leads to possible undesirable behaviors within
a subsystem.
For instance, the HS subsystem would be unable to find the authentication key
of the introduction point circuit leading to a BUG() warning and a duplicate
mark for close on the circuit.
This commit also adds a unit test to make sure we never select marked for
close circuits when upgrading its guard state from waiting for guard to open.
Fixes#30871
Signed-off-by: David Goulet <dgoulet@torproject.org>
When we consider all circuits in "waiting for guard" state to be promoted to
an "open" state, we were considering all circuits, even the one marked for
close.
This ultiamtely triggers a "circuit_has_opened()" called on the circuit that
is marked for close which then leads to possible undesirable behaviors within
a subsystem.
For instance, the HS subsystem would be unable to find the authentication key
of the introduction point circuit leading to a BUG() warning and a duplicate
mark for close on the circuit.
This commit also adds a unit test to make sure we never select marked for
close circuits when upgrading its guard state from waiting for guard to open.
Fixes#30871
Signed-off-by: David Goulet <dgoulet@torproject.org>
When we consider all circuits in "waiting for guard" state to be promoted to
an "open" state, we were considering all circuits, even the one marked for
close.
This ultiamtely triggers a "circuit_has_opened()" called on the circuit that
is marked for close which then leads to possible undesirable behaviors within
a subsystem.
For instance, the HS subsystem would be unable to find the authentication key
of the introduction point circuit leading to a BUG() warning and a duplicate
mark for close on the circuit.
This commit also adds a unit test to make sure we never select marked for
close circuits when upgrading its guard state from waiting for guard to open.
Fixes#30871
Signed-off-by: David Goulet <dgoulet@torproject.org>
Adds ROUTER_AUTHDIR_BUG_ANNOTATIONS to was_router_added_t.
The out-of-order numbering is deliberate: it will be fixed by later commits
for 16564.
Fixes bug 30780; bugfix on 0.2.0.8-alpha.
When this function was implemented, it counted all the entry guards
in the bridge set. But this included previously configured bridges,
as well as currently configured ones! Instead, only count the
_filtered_ bridges (ones that are configured and possibly reachable)
as maybe usable.
Fixes bug 29875; bugfix on 0.3.0.1-alpha.
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>
Previously we purged it in 1-hour increments -- but one-hour is the
maximum TTL for the cache! Now we do it in 25%-TTL increments.
Fixes bug 29617; bugfix on 0.3.5.1-alpha.
This is the first half of implementing proposal 301. The
RecommendedPackages torrc option is marked as obsolete and
the test cases for the option removed. Additionally, the code relating
to generating and formatting package lines in votes is removed.
These lines may still appear in votes from other directory authorities
running earlier versions of the code and so consensuses may still
contain package lines. A new consensus method will be needed to stop
including package lines in consensuses.
Fixes: #28465
To ease debugging of miscount issues, attach vanguards with --loglevel DEBUG
and obtain control port logs (or use any other control port CIRC and
CIRC_MINOR event logging mechanism).
If circuit padding wants to keep a circuit open and pathbias used to ignore
it, pathbias should continue to ignore it.
This may catch other purpose-change related miscounts (such as timeout
measurement, cannibalization, onion service circuit transitions, and
vanguards).
Fortunately, in 0.3.5.1-alpha we improved logging for various
failure cases involved with onion service client auth.
Unfortunately, for this one, we freed the file right before logging
its name.
Fortunately, tor_free() sets its pointer to NULL, so we didn't have
a use-after-free bug.
Unfortunately, passing NULL to %s is not defined.
Fortunately, GCC 9.1.1 caught the issue!
Unfortunately, nobody has actually tried building Tor with GCC 9.1.1
before. Or if they had, they didn't report the warning.
Fixes bug 30475; bugfix on 0.3.5.1-alpha.
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.
For various reasons, this was a nontrivial movement. There are
several places in the code where we do something like "update the
flags on this routerstatus or node if we're an authority", and at
least one where we pretended to be an authority when we weren't.
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.
Manually fix up some reply-generating code that the Coccinelle scripts
won't match. Some more complicated ones remain -- these are mostly
ones that accumulate data to send, and then call connection_buf_add()
or connection_write_str_to_buf() directly.
Create a set of abstractions for controller commands and events to
output replies to the control channel. The control protocol has a
relatively consistent SMTP-like structure, so it's helpful when code
that implements control commands and events doesn't explicitly format
everything on its own.
Split the core reply formatting code out of control_fmt.c into
control_proto.c. The remaining code in control_format.c deals with
specific subsystems and will eventually move to join those subsystems.
