Cryptography External Command Specification v1

[jht5945]

URL: https://ows.hatter.in/rfc1

Key	Value	Comment
No.	RFC#1	-
Author	Hatter Jiang	-
Created	May 14th, 2025	-
Modified	May 14th, 2025	-
Modified	Jul 9th, 2025	external_sign supports --message-type

Introduction

Do ECDH or Sign using external command line.

Commands

Error Result

Field	Type	Description
success	boolean	Always false
error	boolean	Error message

external_spec

Field	Type	Description
success	boolean	Always true
agent	String	Command line agent
specification	String	Specification version
commands	[]String	Supported commands

commandline-cli external_spec

{
  "agent": "card-external-provider/1.13.6",
  "specification": "External/1.0.0-alpha",
  "success": true,
  "commands": ["external_public_key", "external_sign"]
}

external_public_key

Field	Type	Description
success	boolean	Always true
public_key_base64	String	Public key in base64

commandline-cli external_public_key --parameter <PARAMETER>

{
  "public_key_base64": "MFkwEwYHKoZIzj0CAQYIKoZIzj0DAQcDQgAEgSZJRVVOddsE6QRArEZY6I4tsa56P66knLqzHheyps90RA46eqNab0ws8b9LAlrdPCQQHvSdnwTi9OddYhXtyw==",
  "success": true
}

external_sign

Field	Type	Description
success	boolean	Always true
signature_base64	String	Signature in base64

commandline-cli external_sign --parameter <PARAMETER> --alg ES256 --message-base64 <MESSAGE_IN_BASE64> [--message-type raw|sha256|sha384|sha512]

{
  "signature_base64": "MEQCIBMTp4vbtZ9WwUaBiqZe3T+MdzC2BYSteujzSSE/QKmqAiBhic8j/jdUeaWCWQZZlz4G9iiPGcMTAiclFqPoQaiIMg==",
  "success": true
}

external_ecdh

Field	Type	Description
success	boolean	Always true
shared_secret_hex	String	Shared secret in HEX

commandline-cli external_ecdh --parameter <PARAMETER> --epk <PUBLIC_KEY_IN_BASE64>

{
  "shared_secret_hex": "a04ddc1e94a9df5d26a9405940e11498743d08245d654ca6fc9d2c41e602f250",
  "success": true
}