Allowing this didn't do any actual harm, since there aren't any
shared structures or leakable objects here. Still, it's bad style
and might cause trouble in the future.
Closes ticket 27856.
Instead, have it call a mockable function. We don't want
crypto_strongest_rand() to be mockable, since doing so creates a
type error when we call it from ed25519-donna, which we do not build
in a test mode.
Fixes bug 27728; bugfix on 0.3.5.1-alpha
This shouldn't be a user-visible change: nobody has a 16 MB RSA
key that they're trying to use with Tor.
I'm doing this to fix CID 1439330 / ticket 27730, where coverity
complains (on 64-bit) that we are making a comparison that is never
true.
This is an attempt to work around what I think may be a bug in
OSS-Fuzz, which thinks that uninitialized data might be passed to
the curve25519 functions.
On new glibc versions, there's an explicit_bzero(). With openssl,
there's openssl_memwipe().
When no other approach works, use memwipe() and a memory barrier.
This function was a wrapper around RSA_check_key() in openssl, which
checks for invalid RSA private keys (like those where p or q are
composite, or where d is not the inverse of e, or where n != p*q).
We don't need a function like this in NSS, since unlike OpenSSL, NSS
won't let you import a bogus private key.
I've renamed the function and changed its return type to make it
more reasonable, and added a unit test for trying to read a key
where n != p*q.
We used to link both libraries at once, but now that I'm working on
TLS, there's nothing left to keep OpenSSL around for when NSS is
enabled.
Note that this patch causes a couple of places that still assumed
OpenSSL to be disabled when NSS is enabled
- tor-gencert
- pbkdf2
This cleans up a lot of junk from crypto_rsa_openssl, and will
save us duplicated code in crypto_rsa_nss (when it exists).
(Actually, it already exists, but I am going to use git rebase so
that this commit precedes the creation of crypto_rsa_nss.)
This is comparatively straightforward too, except for a couple of
twists:
* For as long as we're building with two crypto libraries, we
want to seed _both_ their RNGs, and use _both_ their RNGs to
improve the output of crypto_strongest_rand()
* The NSS prng will sometimes refuse to generate huge outputs.
When it does, we stretch the output with SHAKE. We only need
this for the tests.
