This makes it so we can handle getting an IPv6 in the 3 different
formats we specified it for in RESOLVED cells,
END_STREAM_REASON_EXITPOLICY cells, and CONNECTED cells.
We don't cache IPv6 addresses yet, since proposal 205 isn't
implemented.
There's a refactored function for parsing connected cells; it has unit
tests.
These options are for telling the SOCKSPort that it should allow or
not allow connections to IPv4/IPv6 addresses.
These aren't implemented yet; this is just the code to read the
options and get them into the entrey_connection_t.
Also, count ipv6 timeouts vs others. If we have too many ipv6
requests time out, then we could be degrading performance because of a
broken DNS server that ignores AAAA requests. Other cases in which
we never learn an AAAA address aren't so bad, since they don't slow
A (ipv4) answers down very much.
This is a relatively simple set of changes: we mostly need to
remove a few "but not for IPv6" changes. We also needed to tweak
the handling of DNS code to generate RESOLVED cells that could get
an IPv6 answer in return.
Now, "accept *:80" means "accept all addresses on port 80", and not
just IPv4. For just v4, say "accept *4:80"; for just v6 say "accept
*6:80".
We can parse these policies from torrc just fine, and we should be
successfully keeping them out of descriptors for now.
We also now include appropriate IPv6 addresses in "reject private:*"
By default, "*" means "All IPv4 addresses" with
tor_addr_parse_mask_ports, so I won't break anything. But if the new
EXTENDED_STAR flag is provided, then * means "any address", *4 means
"any IPv4 address" (that is, 0.0.0.0/0), and "*6" means "any IPv6
address" (that is, [::]/0).
This is going to let us have a syntax for specifying exit policies in
torrc that won't drive people mad.
Also, add a bunch of unit tests for tor_addr_parse_mask_ports to test
these new features, and to increase coverage.
We'd like these functions to be circuit-relative so that we can
implement a per-circuit DNS cache and per-circuit DNS cache rules for
proposal 205 or its successors. I'm doing this now, as a part of the
IPv6 exits code, since there are about to be a few more instances
of code using this.
This is the simplest possible workaround: make it safe to call
circuit_cell_queue_clear() on a non-attached circuit, and make it
safe-but-a-LD_BUG-warning to call update_circuit_on_cmux() on a
non-attached circuit.
LocalWords: unstage src Untracked
Apparently some compilers like to eliminate memset() operations on
data that's about to go out-of-scope. I've gone with the safest
possible replacement, which might be a bit slow. I don't think this
is critical path in any way that will affect performance, but if it
is, we can work on that in 0.2.4.
Fixes bug 7352.
