COSE_Sign messages (multiple signers) can be read, validated, and created #62599
Description
- Read and expose metadata for tagged and untagged COSE_Sign messages
- Validate all signatures with both embedded and detached content, from both formats.
- ECDsa
- RSASSA-PSS (from IETF RFC 8230)
- Create new embedded- and detached- content signatures.
- Countersign existing messages.