7 ms·

Try pasting your cert into https://lapo.it/asn1js/ https://lapo.it/asn1js/ You can see all the parts in the blob: OBJECT IDENTIFIER 1.2.840.10045.2.1

by ASN1 7y ago

Try pasting your cert into https://lapo.it/asn1js/ https://lapo.it/asn1js/ You can see all the parts in the blob: OBJECT IDENTIFIER 1.2.840.10045.2.1 ecPublicKey (ANSI X9.62 public key type) SEQUENCE (6 elem) INTEGER 1 SEQUENCE (2 elem) OBJECT IDENTIFIER 1.2.840.10045.1.1 prime-field (ANSI X9.62 field type) INTEGER (256 bit) 1157920892373161954235709850086879078532699846656405640394575840079088… SEQUENCE (2 elem) OCTET STRING (32 byte) 0000000000000000000000000000000000000000000000000000000000000000 OCTET STRING (32 byte) 0000000000000000000000000000000000000000000000000000000000000007 OCTET STRING (65 byte) 0479BE667EF9DCBBAC55A06295CE870B07029BFCDB2DCE28D959F2815B16F81798483A… INTEGER (256 bit) 1157920892373161954235709850086879078528375642790749043826051631415181… INTEGER 1 This will help you understand the ASN.1 encoding of a cert: http://luca.ntop.org/Teaching/Appunti/asn1.html http://luca.ntop.org/Teaching/Appunti/asn1.html

benth 7y ago
The parent comment is wondering about the structure of the signature and if different curve parameters can be specified for it. How can explicit curve parameters be specified in an ECDSA signature? ecdsaWithSHA256, at least, is simply two bigints. There's no spot for specifying explicit parameters.
- tptacek 7y ago
  This is answered upthread and in RFC 5480: the AlgorithmIdentifier has an ANY OPTIONAL field for parameters.
  - benth 7y ago
    Missed that. Thank you!