The buf_read_from_tls() function was designed to read up to a certain number
of bytes a TLS socket using read_to_chunk_tls() which boils down to SSL_read()
(with OpenSSL, common case).
However, at the end of the loop, the returned number of bytes from
read_to_chunk_tls() was treated like the syscall read() for which if less
bytes than the total asked are returned, it signals EOF.
But, with SSL_read(), it returns up to a TLS record which can be less than
what was asked. The assumption that it was EOF was wrong which made the while
loop exiting before it was able to consume all requested bytes (at_most
parameter).
The general use case that Tor sees is that it will ask the network layer to
give it at most 16KB (that is roughly 32 cells) but because of KIST scheduler,
the highest possible TLS record we currently observe is 4096 bytes (4KB or 8
cells). Thus the loop would at best always return 8 cells even though much
more could be on the TLS socket. See ticket #40006 for more details.
Fixes#40006
Signed-off-by: David Goulet <dgoulet@torproject.org>
I've managed to keep this change mainly contained to our
self-testing module. The changes here are:
* There are two different variables for tracking "is our orport
reachable".
* We have a new function that says whether we can skip a single
family's orport reachability test; the old function for this now
tells whether we can skip _all_ orport reachability testing.
(The name, router_should_skip_orport_reachability_test, is not
so good. I will rename it later if I can think of a good
replacement.)
* The function that launches orport reachability tests now only
launches the ones that haven't completed.
* The function that notes that we're reachable on an ORPort now
takes a family.
* Various log messages are cleaned up.
Since Tor 0.2.9 has been unsupported since January, 0.3.5 is the
oldest supported version, and its features constitute the oldest
recommended feature-set.
This patch updates these recommendations:
DirCache=2
Support for consensus diffs.
New in 0.3.1.1-alpha.
HSDir=2
Support for v3 onion service descriptors.
New in 0.3.0.4-alpha.
HSIntro=4
Support for Ed25519 intropoint authentication keys.
New in 0.3.0-4-alpha.
HSRend=2
Support for rendezvous cells longer than 20 bytes.
New in 0.2.9.4-alpha.
Link=5
Link padding and link padding negotiation.
New in 0.3.3.2-alpha.
LinkAuth=3
Ed25519 link authentication.
New in 0.3.0.1-alpha.
M_SYSCALL is used to report information about a sandbox violation,
but when we don't have a definition for it, it still makes sense to
compile.
Closes ticket 34382.
Resume being willing to use preemptively-built circuits when
UseEntryGuards is set to 0. We accidentally disabled this feature with
that config setting (in our fix for #24469), leading to slower load times.
Fixes bug 34303; bugfix on 0.3.3.2-alpha.
Make Rust protocol version support checks consistent with the
undocumented error behaviour of the corresponding C code.
Fixes bug 34251; bugfix on 0.3.3.5-rc.
Declare support for the onion service introduction point denial of
service extensions, when building tor with Rust.
Fixes bug 34248; bugfix on 0.4.2.1-alpha.
... and DISABLE_ASSERTS_IN_UNIT_TESTS.
Make all of tor's assertion macros support the ALL_BUGS_ARE_FATAL and
DISABLE_ASSERTS_IN_UNIT_TESTS debugging modes.
Implements these modes for IF_BUG_ONCE(). (It used to log a non-fatal
warning, regardless of the debugging mode.)
Fixes bug 33917; bugfix on 0.2.9.1-alpha.
Allow clients and relays to send dual-stack and IPv6-only EXTEND2 cells.
Parse dual-stack and IPv6-only EXTEND2 cells on relays.
Relays do not make connections or extend circuits via IPv6: that's the
next step.
Closes ticket 33901.
Log IPv6 addresses on connections where this relay is the responder.
Previously, responding relays would replace the remote IPv6 address with
the IPv4 address from the consensus.
(The port is replaced with the IPv6 ORPort from the consensus, we will
resolve this issue in 33898.)
Fixes bug 33899; bugfix on 0.3.1.1-alpha.
Consider IPv6 addresses when checking if a connection is canonical.
In 17604, relays assumed that a remote relay could consider an IPv6
connection canonical, but did not set the canonical flag on their side
of the connection.
Fixes bug 33899; bugfix on 0.3.1.1-alpha.
The client auth protocol allows attacker-controlled x25519 private keys being
passed around, which allows an attacker to potentially trigger the all-zeroes
assert for client_auth_sk in hs_descriptor.c:decrypt_descriptor_cookie().
We fixed that by making sure that an all-zeroes client auth key will not be
used.
There are no guidelines for validating x25519 private keys, and the assert was
there as a sanity check for code flow issues (we don't want to enter that
function with an unitialized key if client auth is being used). To avoid such
crashes in the future, we also changed the assert to a BUG-and-err.
This change broke torsocks that by default is expecting an IPv4 for hostname
resolution because it can't ask tor for a specific IP version with the SOCKS5
extension.
PreferIPv6 made it that sometimes the IPv6 could be returned to torsocks that
was expecting an IPv4.
Torsocks is probably a very unique case because the runtime flow is that it
hijacks DNS resolution (ex: getaddrinfo()), gets an IP and then sends it back
for the connect() to happen.
The libc has DNS resolution functions that allows the caller to request a
specific INET family but torsocks can't tell tor to resolve the hostname only
to an IPv4 or IPv6 and thus by default fallsback to IPv4.
Reverting this change into 0.4.3.x series but we'll keep it in the 0.4.4.x
series in the hope that we add this SOCKS5 extension to tor for DNS resolution
and then change torsocks to use that.
Fixes#33804
Signed-off-by: David Goulet <dgoulet@torproject.org>
