When closing parallel introduction points, the given reason (timeout)
was actually changed to "no reason" thus when the circuit purpose was
CIRCUIT_PURPOSE_C_INTRODUCE_ACK_WAIT, we were reporting an introduction
point failure and flagging it "unreachable". After three times, that
intro point gets removed from the rend cache object.
In the case of CIRCUIT_PURPOSE_C_INTRODUCING, the intro point was
flagged has "timed out" and thus not used until the connection to the HS
is closed where that flag gets reset.
This commit adds an internal circuit reason called
END_CIRC_REASON_IP_NOW_REDUNDANT which tells the closing circuit
mechanism to not report any intro point failure.
This has been observed while opening hundreds of connections to an HS on
different circuit for each connection. This fix makes this use case to
work like a charm.
Fixes#13698.
Signed-off-by: David Goulet <dgoulet@ev0ke.net>
We were only using it when smartlist_choose_node_by_bandwidth_weights
failed. But that function could only fail in the presence of
buggy/ancient authorities or in the absence of a consensus. Either
way, it's better to use sensible defaults and a nicer algorithm.
Now, if a router ever changes its microdescriptor, but the new
microdescriptor SHA256 hash has the same 160-bit prefix as the old
one, we treat it as a new microdescriptor when deciding whether to
copy status information.
(This function also is used to compare SHA1 digests of router
descriptors, but don't worry: the descriptor_digest field either holds
a SHA256 hash, or a SHA1 hash padded with 0 bytes.)
Silence clang warnings under --enable-expensive-hardening, including:
+ implicit truncation of 64 bit values to 32 bit;
+ const char assignment to self;
+ tautological compare; and
+ additional parentheses around equality tests. (gcc uses these to
silence assignment, so clang warns when they're present in an
equality test. But we need to use extra parentheses in macros to
isolate them from other code).
By now, support in the network is widespread and it's time to require
more modern crypto on all Tor instances, whether they're clients or
servers. By doing this early in 0.2.6, we can be sure that at some point
all clients will have reasonable support.
Ensure we securely wipe keys from memory after
crypto_digest_get_digest and init_curve25519_keypair_from_file
have finished using them.
Fixes bug 13477.
1. The test that adds things to the cache needs to set the clock back so
that the descriptors it adds are valid.
2. We split ROUTER_NOT_NEW into ROUTER_TOO_OLD, so that we can
distinguish "already had it" from "rejected because of old published
date".
3. We make extrainfo_insert() return a was_router_added_t, and we
make its caller use it correctly. This is probably redundant with
the extrainfo_is_bogus flag.
One pain point in evolving the Tor design and implementing has been
adding code that makes clients reject directory documents that they
previously would have accepted, if those descriptors actually exist.
When this happened, the clients would get the document, reject it,
and then decide to try downloading it again, ad infinitum. This
problem becomes particularly obnoxious with authorities, since if
some authorities accept a descriptor that others don't, the ones
that don't accept it would go crazy trying to re-fetch it over and
over. (See for example ticket #9286.)
This patch tries to solve this problem by tracking, if a descriptor
isn't parseable, what its digest was, and whether it is invalid
because of some flaw that applies to the portion containing the
digest. (This excludes RSA signature problems: RSA signatures
aren't included in the digest. This means that a directory
authority can still put another directory authority into a loop by
mentioning a descriptor, and then serving that descriptor with an
invalid RSA signatures. But that would also make the misbehaving
directory authority get DoSed by the server it's attacking, so it's
not much of an issue.)
We already have a mechanism to mark something undownloadable with
downloadstatus_mark_impossible(); we use that here for
microdescriptors, extrainfos, and router descriptors.
Unit tests to follow in another patch.
Closes ticket #11243.
