This project introduces the prob_distr.c subsystem which implements all the
probability distributions that WTF-PAD needs. It also adds unittests for all of
them.
Code and tests courtesy of Riastradh.
Co-authored-by: Taylor R Campbell <campbell+tor@mumble.net>
Co-authored-by: Mike Perry <mikeperry-git@torproject.org>
Hope is this will make it easier to test on the live tor network.
Does not need to be merged if we don't want to, but will come in handy
for researchers.
Co-authored-by: George Kadianakis <desnacked@riseup.net>
This implements all of the event handling, state machines, and padding
decisions for circuit padding.
I recommend reviewing this after you look at the call-in points into it from
the rest of Tor.
Co-authored-by: George Kadianakis <desnacked@riseup.net>
These callbacks allow the padding state machines to react to various types of
sent and received relay cells.
Co-authored-by: George Kadianakis <desnacked@riseup.net>
These event callbacks allow circuit padding to decide when to attempt to
launch and negotiate new padding machines, and when to tear old ones down.
Co-authored-by: George Kadianakis <desnacked@riseup.net>
This is a good code review start point, to get an overview of the interfaces
and types used in circuit padding.
Co-authored-by: George Kadianakis <desnacked@riseup.net>
We need this for padding negotiation so that we can have later machine
revisions supercede earlier ones.
Co-authored-by: George Kadianakis <desnacked@riseup.net>
Redefine the set of bootstrap phases to allow display of finer-grained
progress in the early connection stages of connecting to a relay.
This includes adding intermediate phases for proxy and PT connections.
Also add a separate new phase to indicate obtaining enough directory
info to build circuits so we can report that independently of actually
initiating an ORCONN to build the first application circuit.
Previously, we would claim to be connecting to a relay when we had
merely finished obtaining directory info.
Part of ticket 27167.
Replace a few invocations of control_event_bootstrap() with calls from
the bootstrap tracker subsystem. This mostly leaves behavior
unchanged. The actual behavior changes come in the next commit.
Part of ticket 27167.
Linked connections aren't woken up by libevent due to I/O but rather
artificially so we can, by chunks, empty the spooled object(s).
Commit 5719dfb48f (in 0.3.4.1-alpha) made it
that the schedule_active_linked_connections_event would be only called once at
startup but this is wrong because then we would never go through again the
active linked connections.
Fortunately, everytime a new linked connection is created, the event is
activated and thus we would go through the active list again. On a busy relay,
this issue is mitigated by that but on a slower relays or bridge, a connection
could get stuck for a while until a new directory information request would
show up.
Fixes#28717, #28912
We now accumulate warning flags in a separate variable,
"TOR_WARNING_FLAGS", and write it to a "warning_flags" file. Then
we test whether the compiler will accept "@warning_flags": if so, we
put "@warning_flags" in the CFLAGS; if not, we copy the contents of
"$TOR_WARNING_FLAGS" into the CFLAGS.
Closes ticket 28924.
Add a tracker for bootstrap progress, tracking events related to
origin circuit and ORCONN states. This uses the ocirc_event and
orconn_event publish-subscribe subsystems.
Part of ticket 27167.
Add a publish-subscribe subsystem to publish messages about changes to
origin circuits.
Functions in circuitbuild.c and circuitlist.c publish messages to this
subsystem.
Move circuit event constants out of control.h so that subscribers
don't have to include all of control.h to take actions based on
messages they receive.
Part of ticket 27167.
Add a publish-subscribe subsystem to publish messages about changes to
OR connections.
connection_or_change_state() in connection_or.c and
control_event_or_conn_event() in control.c publish messages to this
subsystem via helper functions.
Move state constants from connection_or.h to orconn_state.h so that
subscribers don't have to include all of connection_or.h to take
actions based on changes in OR connection state. Move event constants
from control.h for similar reasons.
Part of ticket 27167.
connection_or_change_state() saved an old_state to pass to
channel_tls_handle_state_change_on_orconn(), which promptly cast it to
void. Remove this unused variable and parameter.
This patch changes the CancelIoEx() example code to use CancelIo(),
which is available for older versions of Windows too. I still think the
kernel handles this nicely by sending broken pipes if either side
closes the pipe while I/O operations are pending.
See: https://bugs.torproject.org/28179
Handle `ERROR_BROKEN_PIPE` from ReadFileEx() and WriteFileEx() in
process_win32_stdin_write_done() and
process_win32_handle_read_completion() instead of in the early handler.
This most importantmly makes sure that `reached_eof` is set to true when
these errors appears.
See: https://bugs.torproject.org/28179
