object

jwt_der

DER and PEM helpers for JWK public keys and JOSE signatures.

Availability:

logtalk_load(jwt(loader))

Author: Paulo Moura

Version: 1:0:0

Date: 2026-07-06

Compilation flags:

static, context_switching_calls

Imports:

public jwt_helpers

Uses:

base64

list

user

Remarks:

(none)

Inherited public predicates:

 check_option/1  check_options/1  default_option/1  default_options/1  option/2  option/3  valid_option/1  valid_options/1

Public predicates

public_key_pem/2

Converts a supported JWK public key into PEM SubjectPublicKeyInfo text.

Compilation flags:

static

Template:

public_key_pem(Key,PEM)

Mode and number of proofs:

public_key_pem(+term,-atom) - one_or_error

Exceptions:

Key is not a supported RSA or P-256 EC public JWK:

domain_error(jwt_jwk_public_key,Key)

Key contains Base64URL data with characters outside the Base64URL alphabet:

representation_error(base64)

---

es256_signature_der/2

Converts a raw JOSE ES256 signature into DER-encoded ASN.1 form.

Compilation flags:

static

Template:

es256_signature_der(Signature,DER)

Mode and number of proofs:

es256_signature_der(+list(byte),-list(byte)) - one_or_error

Exceptions:

Signature is not a 64-byte raw ES256 signature:

domain_error(jwt_es256_signature,Signature)

---

Protected predicates

(no local declarations; see entity ancestors if any)

Private predicates

(no local declarations; see entity ancestors if any)

Operators

(none)