Matching Chromium, Go, and TLS 1.3, only allow SHA-256, SHA-384, and
SHA-512 RSA-PSS signatures, where MGF-1 and message hash match and salt
length is hash length. Sadly, we are stuck tolerating an explicit
trailerField for now. See the certificates in cl/362617931.
This also fixes an overflow bug in handling the salt length. On
platforms with 64-bit long and 32-bit int, we would misinterpret, e.g,
2^62 + 32 as 32. Also clean up the error-handling of maskHash. It was
previously handled in a very confusing way; syntax errors in maskHash
would succeed and only be noticed later, in rsa_mgf1_decode.
I haven't done it in this change, but as a followup, we can, like
Chromium, reduce X.509 signature algorithms down to a single enum.
Update-Note: Unusual RSA-PSS combinations in X.509 are no longer
accepted. This same change (actually a slightly stricter version) has
already landed in Chrome.
Bug: 489
Change-Id: I85ca3a4e14f76358cac13e66163887f6dade1ace
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/53865
Auto-Submit: David Benjamin <davidben@google.com>
Reviewed-by: Adam Langley <agl@google.com>
Commit-Queue: Adam Langley <agl@google.com>
X509V3_EXT_d2i should notice if an extension has extra data at the end.
Update-Note: Some previously accepted invalid certicates may be
rejected, either in certificate verification or in X509_get_ext_d2i.
Bug: 352
Change-Id: Iacbb74a52d15bf3318b4cb8271d44b0f0a2df137
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/50285
Reviewed-by: Adam Langley <agl@google.com>
Conscrypt will need these functions. Also fix a bug in
X509_get_extension_flags's error-handling. While I'm here, add
X509_CRL_get0_extensions for completeness. Nothing uses this yet, but
this could later be an alternative to avoid Conscrypt's mess with
templates.
Change-Id: I9393b75fcf53346535e6a4712355be081baa630d
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/42744
Commit-Queue: David Benjamin <davidben@google.com>
Reviewed-by: Adam Langley <agl@google.com>