Add support for custom signature parameters

Many signature types define the digest and public key type by a single OID
such as ecdsa_with_sha256.

Some types (RSA-PSS for example) use a single OID to indicate the signature
scheme and additional parameters are encoded in the AlgorithmIdentifier.

Add an X509_SIG_INFO structure to contain details about the signature type:
specifically the digest algorithm, public key algorithm, security bits and
various flags. This supports both existing algorithms and more complex
types.

Add accessors for the structure and a special case that retrieves signature
information from a certificate.

Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/3301)

1 files changed, 1 insertions, 0 deletions

diff --git a/crypto/x509v3/v3_purp.c b/crypto/x509v3/v3_purp.c
index fa5c425..2ff8854 100644
--- a/crypto/x509v3/v3_purp.c
+++ b/crypto/x509v3/v3_purp.c
@@ -488,6 +488,7 @@ static void x509v3_cache_extensions(X509 *x)
             break;
         }
     }
+    x509_init_sig_info(x);
     x->ex_flags |= EXFLAG_SET;
 }