This commit refactors the existing decryption code to make it compatible with
a new logic for when the client authorization is enabled.
Signed-off-by: David Goulet <dgoulet@torproject.org>
Fun fact: these files used to be called log.[ch] until we ran into
conflicts with systems having a log.h file. But now that we always
include "lib/log/log.h", we should be fine.
This function -- a mock replacement used only for fuzzing -- would
have a buffer overflow if it got an RSA key whose modulus was under
20 bytes long.
Fortunately, Tor itself does not appear to have a bug here.
Fixes bug 24247; bugfix on 0.3.0.3-alpha when fuzzing was
introduced. Found by OSS-Fuzz; this is OSS-Fuzz issue 4177.
If it decrypts something that turns out to start with a NUL byte,
then decrypt_desc_layer() will return 0 to indicate the length of
its result. But 0 also indicates an error, which causes the result
not to be freed by decrypt_desc_layer()'s callers.
Since we're trying to stabilize 0.3.2.x, I've opted for the simpler
possible fix here and made it so that an empty decrypted string will
also count as an error.
Fixes bug 24150 and OSS-Fuzz issue 3994.
The original bug was present but unreachable in 0.3.1.1-alpha. I'm
calling this a bugfix on 0.3.2.1-alpha since that's the first version
where you could actually try to decrypt these descriptors.
The new decryption function performs no decryption, skips the salt,
and doesn't check the mac. This allows us to fuzz the
hs_descriptor.c code using unencrypted descriptor test, and exercise
more of the code.
Related to 21509.
At first, we put the tor_git_revision constant in tor_main.c, so
that we wouldn't have to recompile config.o every time the git
revision changed. But putting it there had unintended side effect
of forcing every program that wanted to link libor.a (including
test, test-slow, the fuzzers, the benchmarks, etc) to declare their
own tor_git_revision instance.
That's not very nice, especially since we want to start supporting
others who want to link against Tor (see 23846).
So, create a new git_revision.c file that only contains this
constant, and remove the duplicated boilerplate from everywhere
else.
Part of implementing ticket 23845.
