Only some very ancient distributions don't ship with Libevent 2 anymore,
even the oldest supported Ubuntu LTS version has it. This allows us to
get rid of a lot of compat code.
The Autoconf macro AC_USE_SYSTEM_EXTENSIONS defines preprocessor macros
which turn on extensions to C and POSIX. The macro also makes it easier
for developers to use the extensions without needing (or forgetting) to
define them manually.
The macro can be safely used because it was introduced in Autoconf 2.60
and Tor requires Autoconf 2.63 and above.
This is a big-ish patch, but it's very straightforward. Under this
clang warning, we're not actually allowed to have a global variable
without a previous extern declaration for it. The cases where we
violated this rule fall into three roughly equal groups:
* Stuff that should have been static.
* Stuff that was global but where the extern was local to some
other C file.
* Stuff that was only global when built for the unit tests, that
needed a conditional extern in the headers.
The first two were IMO genuine problems; the last is a wart of how
we build tests.
This warning, IIUC, means that the compiler doesn't like it when it
sees a NULL check _after_ we've already dereferenced the
variable. In such cases, it considers itself free to eliminate the
NULL check.
There are a couple of tricky cases:
One was the case related to the fact that tor_addr_to_in6() can
return NULL if it gets a non-AF_INET6 address. The fix was to
create a variant which asserts on the address type, and never
returns NULL.
So, back long ago, XXX012 meant, "before Tor 0.1.2 is released, we
had better revisit this comment and fix it!"
But we have a huge pile of such comments accumulated for a large
number of released versions! Not cool.
So, here's what I tried to do:
* 0.2.9 and 0.2.8 are retained, since those are not yet released.
* XXX+ or XXX++ or XXX++++ or whatever means, "This one looks
quite important!"
* The others, after one-by-one examination, are downgraded to
plain old XXX. Which doesn't mean they aren't a problem -- just
that they cannot possibly be a release-blocking problem.
We need to define this function when compiling with clang -m32 -ftrapv,
since otherwise we get link errors, since apparently some versions
of libclang_rt.builtins don't define a version of it that works? Or
clang doesn't know to look for it?
This definition is taken from the LLVM source at
https://llvm.org/svn/llvm-project/compiler-rt/trunk/lib/builtins/mulodi4.c
I've also included the license (dual BSD-ish/MIT-ish).
We know there are overflows in curve25519-donna-c32, so we'll have
to have that one be fwrapv.
Only apply the asan, ubsan, and trapv options to the code that does
not need to run in constant time. Those options introduce branches
to the code they instrument.
(These introduced branches should never actually be taken, so it
might _still_ be constant time after all, but branch predictors are
complicated enough that I'm not really confident here. Let's aim for
safety.)
Closes 17983.
* SHA-3/SHAKE use little endian for certain things, so byteswap as
needed.
* The code was written under the assumption that unaligned access to
quadwords is allowed, which isn't true particularly on non-Intel.
Yes, we could cast to unsigned char first, but it's probably safest
to just use our own (in test_util), or remove bad-idea features that
we don't use (in readpassphrase.c).
Fixes 18728.
The digest routines use init/update/sum, where sum will automatically
copy the internal state to support calculating running digests.
The XOF routines use init/absorb/squeeze, which behave exactly as stated
on the tin.
Apparently this only happens with clang (or with some particular
clang versions), and only on i386.
Fixes 16970; bug not in any released Tor.
Found by Teor; fix from Yawning.
This probably requires the user to manually set CFLAGS, but should
result in a net gain on 32 bit x86. Enabling SSE2 support would be
possible on x86_64, but will result in slower performance.
Implements feature #16535.
The code was always in our Ed25519 wrappers, so enable it when using
the ed25519-donna backend, and deal with the mocking related
crypto_rand silliness.
Implements feature 16533.
The only reason 16 byte alignment is required is for SSE2 load and
store operations, so only align datastructures to 16 byte boundaries
when building with SSE2 support.
This fixes builds with GCC SSP on platforms that don't have special
case code to do dynamic stack re-alignment (everything not x86/x86_64).
Fixes bug #16666.
This needs to be done to allow for the possibility of removing the
ref10 code at a later date, though it is not performance critical.
When integrated by kludging it into tor, it passes unit tests, and is
twice as fast.
Integrating it the "wrong" way into common/crypto_ed25519.c passes
`make check`, and there appear to be some known answer tests for this,
so I assume I got it right.
Blinding a public key goes from 139.10 usec to 70.78 usec using
ed25519-donna (NB: Turboboost/phase of moon), though the code isn't
critical path, so supporting it is mostly done for completeness.
Integrate ed25519-donna into the build process, and provide an
interface that matches the `ref10` code. Apart from the blinding and
Curve25519 key conversion, this functions as a drop-in replacement for
ref10 (verified by modifying crypto_ed25519.c).
Tests pass, and the benchmarks claim it is quite a bit faster, however
actually using the code requires additional integration work.
The compiler is allowed to assume that a "uint64_t *" is aligned
correctly, and will inline a version of memcpy that acts as such.
Use "uint8_t *", so the compiler does the right thing.
This is meant to prevent memory corruption bugs from doing
unspeakable infinite-loop-like things to the hashtables. Addresses
ticket 11737. We should disable these if they turn out to be
expensive.
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).
This helps us avoid undefined behavior. It's based on a patch from teor,
except that I wrote a perl script to regenerate the patch:
#!/usr/bin/perl -p -w -i
BEGIN { %vartypes = (); }
if (/^[{}]/) {
%vartypes = ();
}
if (/^ *crypto_int(\d+) +([a-zA-Z_][_a-zA-Z0-9]*)/) {
$vartypes{$2} = $1;
} elsif (/^ *(?:signed +)char +([a-zA-Z_][_a-zA-Z0-9]*)/) {
$vartypes{$1} = '8';
}
# This fixes at most one shift per line. But that's all the code does.
if (/([a-zA-Z_][a-zA-Z_0-9]*) *<< *(\d+)/) {
$v = $1;
if (exists $vartypes{$v}) {
s/$v *<< *(\d+)/SHL$vartypes{$v}($v,$1)/;
}
}
# remove extra parenthesis
s/\(SHL64\((.*)\)\)/SHL64\($1\)/;
s/\(SHL32\((.*)\)\)/SHL32\($1\)/;
s/\(SHL8\((.*)\)\)/SHL8\($1\)/;
There are some loops of the form
for (i=1;i<1;++i) ...
And of course, if the loop index is initialized to 1, it will never
be less than 1, and the loop body will never be executed. This
upsets coverity.
Patch fixes CID 1221543 and 1221542
When size_t is the most memory you can have, make sure that things
referring to real parts of memory are size_t, not uint64_t or off_t.
But not on any released Tor.
This implementation allows somebody to add a blinding factor to a
secret key, and a corresponding blinding factor to the public key.
Robert Ransom came up with this idea, I believe. Nick Hopper proved a
scheme like this secure. The bugs are my own.
For proposal 228, we need to cross-certify our identity with our
curve25519 key, so that we can prove at descriptor-generation time
that we own that key. But how can we sign something with a key that
is only for doing Diffie-Hellman? By converting it to the
corresponding ed25519 point.
See the ALL-CAPS warning in the documentation. According to djb
(IIUC), it is safe to use these keys in the ways that ntor and prop228
are using them, but it might not be safe if we start providing crazy
oracle access.
(Unit tests included. What kind of a monster do you take me for?)
This is another case where DJB likes sticking the whole signature
prepended to the message, and I don't think that's the hottest idea.
The unit tests still pass.
This reduces the likelihood that I have made any exploitable errors
in the encoding/decoding.
This commit also imports the trunnel runtime source into Tor.
Nick Mathewson
Sebastian Hahn
cypherpunks
Roger Dingledine
Yawning Angel
teor (Tim Wilson-Brown)
Jeremy