RFC 5758 §3.2 says the encoding MUST omit the parameters field for the ECDSA signature OIDs — no NULL, unlike RSA — a detail strict parsers enforce. The signature value is a DER SEQUENCE of r and s.
1.2.840.10045.4.3.2
ecdsa-with-SHA256
ecdsa-with-SHA256: an ECDSA signature with SHA-256, used on certificates issued by ECDSA keys.
1.2.840.10045.4.3.2 identifies ecdsa-with-SHA256, a signature algorithm. DER: 06082a8648ce3d040302.
- Dotted notation
1.2.840.10045.4.3.2- DER encoding
06082a8648ce3d040302- Category
- a signature algorithm
- Also known as
ES256, ECDSA-SHA256- OpenSSL short name
ecdsa-with-SHA256- Listed by
- the ecdsa.com catalog