cosign

Documentation

Overview

Package cosign contains functionalities to interact with signatures generated by cosign. https://github.com/sigstore/cosign/blob/main/specs/SIGNATURE_SPEC.md.

Index

• Constants
• func NewFakeSignature(data string, sigAlg oci.SigningAlgorithm) oci.Signature
• type Sig
  • func (s Sig) Base64Encoded() (string, error)
  • func (s Sig) Payload() ([]byte, error)
  • func (s Sig) PublicKey() ([]byte, error)
  • func (s Sig) SigningAlgorithm() (oci.SigningAlgorithm, error)
  • func (s Sig) String() string

Constants

const CosignSigKey = "dev.cosignproject.cosign/signature"

CosignSigKey is the key of the cosign-generated signature embedded in OCI image manifest.

Functions

func NewFakeSignature

func NewFakeSignature(data string, sigAlg oci.SigningAlgorithm) oci.Signature

NewFakeSignature constructs a new fake oci.Signature given data and signature algorithm.

Types

type Sig

type Sig struct {
	// Layer represents a layer descriptor for OCI image manifest.
	// This contains the simple signing payload digest and Cosign signature,
	// collected from the OCI image manifest object found using https://github.com/sigstore/cosign/blob/main/specs/SIGNATURE_SPEC.md#tag-based-discovery.
	Layer v1.Descriptor
	// Blob represents the opaque data uploaded to OCI registry associated with the layer.
	// This contains the Simple Signing Payload as described in https://github.com/sigstore/cosign/blob/main/specs/SIGNATURE_SPEC.md#tag-based-discovery.
	Blob []byte
	// SourceRepo represents the location that stores this signature.
	SourceRepo string
}

Sig implements oci.Signature interface for cosign-generated signatures.

func (Sig) Base64Encoded

func (s Sig) Base64Encoded() (string, error)

Base64Encoded implements oci.Signature interface.

func (Sig) Payload

func (s Sig) Payload() ([]byte, error)

Payload implements oci.Signature interface.

func (Sig) PublicKey

func (s Sig) PublicKey() ([]byte, error)

PublicKey implements oci.Signature interface. Since public key is attached to the `optional` field of payload, we don't actually implement this method. Instead we send payload directly to the Attestation service and let the service parse the payload.

func (Sig) SigningAlgorithm

func (s Sig) SigningAlgorithm() (oci.SigningAlgorithm, error)

SigningAlgorithm implements oci.Signature interface. Since signing algorithm is attached to the `optional` field of payload, we don't actually implement this method. Instead we send payload directly to the Attestation service and let the service parse the payload.

func (Sig) String

func (s Sig) String() string

String returns signature details