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>
This is designed to be the minimal infrastructure required to support
using BoringSSL in the Rust ecosystem without fear of ABI drift. Bindgen
is used to generate Rust bindings in lockstep with the rest of the
build. `rust-openssl` can consume these generated bindings with minimal
changes.
Change-Id: I1dacd36a4131e22a930ebb01da00407e8465ad7e
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/49645
Reviewed-by: David Benjamin <davidben@google.com>
Reviewed-by: Adam Langley <agl@google.com>
Commit-Queue: David Benjamin <davidben@google.com>
OpenSSL 1.1.0 made this structure opaque. I don't think we particularly
need to make it opaque, but external code uses it. Also add
RSA_test_flags.
Change-Id: I136d38e72ec4664c78f4d1720ec691f5760090c1
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/50605
Reviewed-by: Adam Langley <agl@google.com>
This doesn't affect RSA key generation, which uses
BN_prime_checks_for_generation.
Change-Id: Ibf32c0c4bc9fed369e8f8a1efea72c5bd39185a9
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/49426
Reviewed-by: David Benjamin <davidben@google.com>
Commit-Queue: David Benjamin <davidben@google.com>
Adam Langley
Benjamin Brittain
David Benjamin
jakemas
Adam Langley