This replaces our dynamically creating singleton EC_GROUPs from curve
data with static EC_GROUP instances.
They're just shy of being fully static because delocate still forces us
go to through CRYPTO_once to initialize structures with pointers.
(Though, without delocate, the loader would need similar initialization
via a runtime relocation.)
This means we can now have functions like EC_group_p256(), analogous to
EVP_sha256(). These are infallible functions that return const EC_GROUP
pointers. Although there is an initial 2KiB hit to binary size (now we
precompute a few more Montgomery values), I'm hoping it'll eventually
help binaries that only use a few of the curves to drop the others. Also
it removes some locks used to initialize the static curve objects, as
well as removing an annoying error condition.
Bug: 20
Change-Id: Id051c5439f2b2fe2b09bf10964d656503ee27d9e
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/60931
Commit-Queue: David Benjamin <davidben@google.com>
Reviewed-by: Adam Langley <agl@google.com>
Also add public APIs for this, now that the specification is no longer
expected to change, and because a project external to the library wishes
to use it.
For now, I've kept the P-256 version using the generic felem_exp, but we
should update that to use the specialized field arithmetic.
Trust Tokens will presumably move to this later and, in the meantime,
another team wants this.
Bug: chromium:1414562
Change-Id: Ie38203b4439ff55659c4fb2070f45d524c55aa2a
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/57147
Commit-Queue: David Benjamin <davidben@google.com>
Reviewed-by: Steven Valdez <svaldez@google.com>
OpenSSL added a bunch of these. oct2priv is a little weird (see
https://crbug.com/boringssl/534), but I've made it match OpenSSL and
set_private_key for now. But I think we should reduce the state-space a
bit.
EC_KEY_oct2priv behaves slightly differently from upstream OpenSSL in
one way: we reject inputs that aren't exactly the right size. This
matches the OpenSSL documentation (the OCTET STRING inside an
ECPrivateKey, per spec, is fixed-width), but not OpenSSL's behavior.
Update-note: see go/xshow when incorporating this change internally.
Change-Id: I33863d773ac4c7f3eabf4ffda157e8250c7fdbd9
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/55066
Reviewed-by: Adam Langley <agl@google.com>
Commit-Queue: David Benjamin <davidben@google.com>
BN_mod_sqrt implements the Tonelli–Shanks algorithm, which requires a
prime modulus. It was written such that, given a composite modulus, it
would sometimes loop forever. This change fixes the algorithm to always
terminate. However, callers must still pass a prime modulus for the
function to have a defined output.
In OpenSSL, this loop resulted in a DoS vulnerability, CVE-2022-0778.
BoringSSL is mostly unaffected by this. In particular, this case is not
reachable in BoringSSL from certificate and other ASN.1 elliptic curve
parsing code. Any impact in BoringSSL is limited to:
- Callers of EC_GROUP_new_curve_GFp that take untrusted curve parameters
- Callers of BN_mod_sqrt that take untrusted moduli
This CL updates documentation of those functions to clarify that callers
should not pass attacker-controlled values. Even with the infinite loop
fixed, doing so breaks preconditions and will give undefined output.
Change-Id: I64dc1220aaaaafedba02d2ac0e4232a3a0648160
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/51925
Reviewed-by: Adam Langley <agl@google.com>
Reviewed-by: Martin Kreichgauer <martinkr@google.com>
Commit-Queue: Adam Langley <agl@google.com>
I got the values flipped around. Also cryptography.io wants
EC_GROUP_get_asn1_flag to check a curve's encoding. We (mostly) only
support named curves, so just return OPENSSL_EC_NAMED_CURVE.
Change-Id: I544e76b7380ecd8dceb1df3db4dd4cf5cb322352
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/46024
Reviewed-by: Adam Langley <agl@google.com>
Commit-Queue: David Benjamin <davidben@google.com>
Change-Id: I814f55742910c519e9b64aca1b15a4d754adc541
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/44944
Commit-Queue: Adam Langley <agl@google.com>
Commit-Queue: David Benjamin <davidben@google.com>
Reviewed-by: David Benjamin <davidben@google.com>