These were found by looking for tor_snprintf() instances that were
preceeded closely by tor_malloc(), though I probably converted some
more snprintfs as well.
(In every case, make sure that the length variable (if any) is
removed, renamed, or lowered, so that anything else that might have
assumed a longer buffer doesn't exist.)
To solve bug 4779, we want to avoid OpenSSL 1.0.0's counter mode.
But Fedora (and maybe others) lie about the actual OpenSSL version,
so we can't trust the header to tell us if it's safe.
Instead, let's do a run-time test to see whether it's safe, and if
not, use our built-in version.
fermenthor contributed a pretty essential fixup to this patch. Thanks!
MAX_DNS_LABEL_SIZE was only defined for old versions of openssl, which
broke the build. Spotted by xiando. Fixes bug 4413; not in any released
version.
The thing that's limited to 63 bytes is a "label", not a hostname.
Docment input constraints and behavior on bogus inputs.
Generally it's better to check for overflow-like conditions before
than after. In this case, it's not a true overflow, so we're okay,
but let's be consistent.
pedantic less->fewer in the documentation
Fixes bug 4413; bugfix on xxxx.
Hostname components cannot be larger than 63 characters.
This simple check makes certain randlen cannot overflow rand_bytes_len.
Previously we required 1.0.0, but there was a bug in the 1.0.0 counter
mode. Found by Pascal. Fixes bug 4779.
A more elegant solution would be good here if somebody has time to code
one.
If a relay is dormant at startup, it will call init_keys before
crypto_set_tls_dh_prime. This is bad. Let's make it not so bad, because
someday it *will* happen again.
Comments below focus on changes, see diff for added code.
New type tor_addr_port_t holding an IP address and a TCP/UDP port.
New flag in routerinfo_t, ipv6_preferred. This should go in the
node_t instead but not now.
Replace node_get_addr() with
- node_get_prim_addr() for primary address, i.e. IPv4 for now
- node_get_pref_addr() for preferred address, IPv4 or IPv6.
Rename node_get_addr_ipv4h() node_get_prim_addr_ipv4h() for
consistency. The primary address will not allways be an IPv4 address.
Same for node_get_orport() -> node_get_prim_orport().
Rewrite node_is_a_configured_bridge() to take all OR ports into account.
Extend argument list to extend_info_from_node and
extend_info_from_router with a flag indicating if we want to use the
routers primary address or the preferred address. Use the preferred
address in as few situtations as possible for allowing clients to
connect to bridges over IPv6.
Instead of only writing the dynamic DH prime modulus to a file, write
the whole DH parameters set for forward compatibility. At the moment
we only accept '2' as the group generator.
The DH parameters gets stored in base64-ed DER format to the
'dynamic_dh_params' file.
Let's *not* expose more cross-platform-compatibility structures, or
expect code to use them right.
Also, don't fclose() stdout_handle and stdin_handle until we do
tor_process_handle_destroy, or we risk a double-fclose.
This shaves about 7% off our per-cell AES crypto time for me; the
effect for accelerated AES crypto should be even more, since the AES
calculation itself will make an even smaller portion of the
counter-mode performance.
(We don't want to do this for pre-1.0.0 OpenSSL, since our AES_CTR
implementation was actually faster than OpenSSL's there, by about
10%.)
Fixes issue #4526.
This is a fancier bug4457 workaround for 0.2.3. In 0.2.2, we could
just tell Libevent "Don't enable locking!" so it wouldn't try to make
the event_base notifiable. But for IOCP, we need a notifiable base.
(Eventually, we'll want a notifiable base for other stuff, like
multithreaded crypto.) So the solution is to try a full-featured
initialization, and then retry with all the options turned off if that
fails.
Conflicts:
src/common/compat_libevent.c
Resolving conflict by not taking 7363eae13c ("Use the
EVENT_BASE_FLAG_NOLOCK flag to prevent socketpair() invocation"): in
Tor 0.2.3.x, we _do_ sometimes use notifiable event bases.
In Tor 0.2.2, we never need the event base to be notifiable, since we
don't call it from other threads. This is a workaround for bug 4457,
which is not actually a Tor bug IMO.
This thing was pretty pointless on versions of OpenSSL 0.9.8 and later,
and almost totally pointless on OpenSSL 1.0.0.
Also, favor EVP by default, since it lets us get hardware acceleration
where present. (See issue 4442)
The old behavior was susceptible to the compiler optimizing out our
assertion check, *and* could still overflow size_t on 32-bit systems
even when it did work.
- Rename tor_tls_got_server_hello() to tor_tls_got_client_hello().
- Replaced some aggressive asserts with LD_BUG logging.
They were the innocent "I believe I understand how these callbacks
work, and this assert proves it" type of callbacks, and not the "If
this statement is not true, computer is exploding." type of
callbacks.
- Added a changes file.
In a2bb0bf we started using a separate client identity key. When we are
in "public server mode" (that means not a bridge) we will use the same
key. Reusing the key without doing the proper refcounting leads to a
segfault on cleanup during shutdown. Fix that.
Also introduce an assert that triggers if our refcount falls below 0.
That should never happen.
* Make tor_tls_context_new internal to tortls.c, and return the new
tor_tls_context_t from it.
* Add a public tor_tls_context_init wrapper function to replace it.
Conflicts:
src/or/main.c
src/or/router.c
SSL_read(), SSL_write() and SSL_do_handshake() can always progress the
SSL protocol instead of their normal operation, this means that we
must be checking for needless renegotiations after they return.
Introduce tor_tls_got_excess_renegotiations() which makes the
tls->server_handshake_count > 2
check for us, and use it in tor_tls_read() and tor_tls_write().
Cases that should not be handled:
* SSL_do_handshake() is only called by tor_tls_renegotiate() which is a
client-only function.
* The SSL_read() in tor_tls_shutdown() does not need to be handled,
since SSL_shutdown() will be called if SSL_read() returns an error.
From the code:
zlib 1.2.4 and 1.2.5 do some "clever" things with macros. Instead of
saying "(defined(FOO) ? FOO : 0)" they like to say "FOO-0", on the theory
that nobody will care if the compile outputs a no-such-identifier warning.
Sorry, but we like -Werror over here, so I guess we need to define these.
I hope that zlib 1.2.6 doesn't break these too.
Possible fix for bug 1526.
Since we check for naughty renegotiations using
tor_tls_t.server_handshake_count we don't need that semi-broken
function (at least till there is a way to disable rfc5746
renegotiations too).
Switch 'server_handshake_count' from a uint8_t to 2 unsigned int bits.
Since we won't ever be doing more than 3 handshakes, we don't need the
extra space.
Toggle tor_tls_t.got_renegotiate based on the server_handshake_count.
Also assert that when we've done two handshakes as a server (the initial
SSL handshake, and the renegotiation handshake) we've just
renegotiated.
Finally, in tor_tls_read() return an error if we see more than 2
handshakes.
The renegotiation callback was called only when the first Application
Data arrived, instead of when the renegotiation took place.
This happened because SSL_read() returns -1 and sets the error to
SSL_ERROR_WANT_READ when a renegotiation happens instead of reading
data [0].
I also added a commented out aggressive assert that I won't enable yet
because I don't feel I understand SSL_ERROR_WANT_READ enough.
[0]: Look at documentation of SSL_read(), SSL_get_error() and
SSL_CTX_set_mode() (SSL_MODE_AUTO_RETRY section).
Introduce tor_tls_state_changed_callback(), which handles every SSL
state change.
The new function tor_tls_got_server_hello() is called every time we
send a ServerHello during a v2 handshake, and plays the role of the
previous tor_tls_server_info_callback() function.
- Add a tor_process_get_pid() function that returns the PID of a
process_handle_t.
- Conform to make check-spaces.
- Add some more documentation.
- Improve some log messages.
It's too risky to have a function where if you leave one parameter
NULL, it splits up address:port strings, but if you set it, it does
hostname resolution.
Under the new convention, having a tor_addr.*lookup function that
doesn't do hostname resolution is too close for comfort.
I used this script here, and have made no other changes.
s/tor_addr_parse_reverse_lookup_name/tor_addr_parse_PTR_name/g;
s/tor_addr_to_reverse_lookup_name/tor_addr_to_PTR_name/g;
Now let's have "lookup" indicate that there can be a hostname
resolution, and "parse" indicate that there wasn't. Previously, we
had one "lookup" function that did resolution; four "parse" functions,
half of which did resolution; and a "from_str()" function that didn't
do resolution. That's confusing and error-prone!
The code changes in this commit are exactly the result of this perl
script, run under "perl -p -i.bak" :
s/tor_addr_port_parse/tor_addr_port_lookup/g;
s/parse_addr_port(?=[^_])/addr_port_lookup/g;
s/tor_addr_from_str/tor_addr_parse/g;
This patch leaves aton and pton alone: their naming convention and
behavior is is determined by the sockets API.
More renaming may be needed.
Right now we can take the digests only of an RSA key, and only expect to
take the digests of an RSA key. The old tor_cert_get_id_digests() would
return a good set of digests for an RSA key, and an all-zero one for a
non-RSA key. This behavior is too error-prone: it carries the risk that
we will someday check two non-RSA keys for equality and conclude that
they must be equal because they both have the same (zero) "digest".
Instead, let's have tor_cert_get_id_digests() return NULL for keys we
can't handle, and make its callers explicitly test for NULL.
Our keys and x.509 certs are proliferating here. Previously we had:
An ID cert (using the main ID key), self-signed
A link cert (using a shorter-term link key), signed by the ID key
Once proposal 176 and 179 are done, we will also have:
Optionally, a presentation cert (using the link key),
signed by whomever.
An authentication cert (using a shorter-term ID key), signed by
the ID key.
These new keys are managed as part of the tls context infrastructure,
since you want to rotate them under exactly the same circumstances,
and since they need X509 certificates.
GCC 4.2 and maybe other compilers optimize away unsigned integer
overflow checks of the form (foo + bar < foo), for all bar.
Fix one such check in `src/common/OpenBSD_malloc_Linux.c'.
After a stream reached eof, we fclose it, but then
test_util_spawn_background_partial_read() reads from it again, which causes
an error and thus another fclose(). Some platforms are fine with this, others
(e.g. debian-sid-i386) trigger a double-free() error. The actual code used by
Tor (log_from_pipe() and tor_check_port_forwarding()) handle this case
correctly.
Mainly used for testing reading from subprocesses. To be more generic
we now pass in a pointer to a process_handle_t rather than a Windows-
specific HANDLE.
