For consistency and to avoid a pedantic GCC warning (even though it's
mostly old legacy code).

Change-Id: Iea63eb0a82ff52914adc33b83e48450f4f6a49ef
Reviewed-on: https://boringssl-review.googlesource.com/11021
Reviewed-by: Adam Langley <agl@google.com>
Commit-Queue: Adam Langley <agl@google.com>
CQ-Verified: CQ bot account: commit-bot@chromium.org <commit-bot@chromium.org>

I messed up a few of these.

ASN1_R_UNSUPPORTED_ALGORITHM doesn't exist. X509_R_UNSUPPORTED_ALGORITHM does
exist as part of X509_PUBKEY_set, but the SPKI parser doesn't emit this. (I
don't mind the legacy code having really weird errors, but since EVP is now
limited to things we like, let's try to keep that clean.) To avoid churn in
Conscrypt, we'll keep defining X509_R_UNSUPPORTED_ALGORITHM, but not actually
do anything with it anymore.  Conscrypt was already aware of
EVP_R_UNSUPPORTED_ALGORITHM, so this should be fine. (I don't expect
EVP_R_UNSUPPORTED_ALGORITHM to go away. The SPKI parsers we like live in EVP
now.)

A few other ASN1_R_* values didn't quite match upstream, so make those match
again. Finally, I got some of the rsa_pss.c values wrong. Each of those
corresponds to an (overly specific) RSA_R_* value in upstream. However, those
were gone in BoringSSL since even the initial commit. We placed the RSA <-> EVP
glue in crypto/evp (so crypto/rsa wouldn't depend on crypto/evp) while upstream
placed them in crypto/rsa.

Since no one seemed to notice the loss of RSA_R_INVALID_SALT_LENGTH, let's undo
all the cross-module errors inserted in crypto/rsa. Instead, since that kind of
specificity is not useful, funnel it all into X509_R_INVALID_PSS_PARAMETERS
(formerly EVP_R_INVALID_PSS_PARAMETERS, formerly RSA_R_INVALID_PSS_PARAMETERS).

Reset the error codes for all affected modules.

(That our error code story means error codes are not stable across this kind of
refactoring is kind of a problem. Hopefully this will be the last of it.)

Change-Id: Ibfb3a0ac340bfc777bc7de6980ef3ddf0a8c84bc
Reviewed-on: https://boringssl-review.googlesource.com/7458
Reviewed-by: Emily Stark (Dunn) <estark@google.com>
Reviewed-by: David Benjamin <davidben@google.com>

People seem to condition on these a lot. Since this code has now been moved
twice, just make them all cross-module errors rather than leave a trail of
renamed error codes in our wake.

Change-Id: Iea18ab3d320f03cf29a64a27acca119768c4115c
Reviewed-on: https://boringssl-review.googlesource.com/7431
Reviewed-by: Emily Stark (Dunn) <estark@google.com>
Reviewed-by: David Benjamin <davidben@google.com>

All the signature algorithm logic depends on X509_ALGOR. This also
removes the X509_ALGOR-based EVP functions which are no longer used
externally. I think those APIs were a mistake on my part. The use in
Chromium was unnecessary (and has since been removed anyway). The new
X.509 stack will want to process the signatureAlgorithm itself to be
able to enforce policies on it.

This also moves the RSA_PSS_PARAMS bits to crypto/x509 from crypto/rsa.
That struct is also tied to crypto/x509. Any new RSA-PSS code would
have to use something else anyway.

BUG=499653

Change-Id: I6c4b4573b2800a2e0f863d35df94d048864b7c41
Reviewed-on: https://boringssl-review.googlesource.com/7025
Reviewed-by: Adam Langley <agl@google.com>