toolkit/client: fix FindProof to handle self-delegation properly

pkg/claims/claims.go

@@ -1,265 +0,0 @@
-package claims
-
-import (
-	"errors"
-	"fmt"
-	"iter"
-	"sort"
-	"strings"
-
-	"github.com/ipld/go-ipld-prime"
-	"github.com/ipld/go-ipld-prime/printer"
-
-	"github.com/ucan-wg/go-ucan/pkg/policy/literal"
-	"github.com/ucan-wg/go-ucan/pkg/secretbox"
-)
-
-var ErrNotFound = errors.New("key not found in claims")
-
-var ErrNotEncryptable = errors.New("value of this type cannot be encrypted")
-
-// Claims is a container for claims key-value pairs in an attestation token.
-// This also serves as a way to construct the underlying IPLD data with minimum allocations
-// and transformations, while hiding the IPLD complexity from the caller.
-type Claims struct {
-	// This type must be compatible with the IPLD type represented by the IPLD
-	// schema { String : Any }.
-
-	Keys   []string
-	Values map[string]ipld.Node
-}
-
-// NewClaims constructs a new Claims.
-func NewClaims() *Claims {
-	return &Claims{Values: map[string]ipld.Node{}}
-}
-
-// GetBool retrieves a value as a bool.
-// Returns ErrNotFound if the given key is missing.
-// Returns datamodel.ErrWrongKind if the value has the wrong type.
-func (m *Claims) GetBool(key string) (bool, error) {
-	v, ok := m.Values[key]
-	if !ok {
-		return false, ErrNotFound
-	}
-	return v.AsBool()
-}
-
-// GetString retrieves a value as a string.
-// Returns ErrNotFound if the given key is missing.
-// Returns datamodel.ErrWrongKind if the value has the wrong type.
-func (m *Claims) GetString(key string) (string, error) {
-	v, ok := m.Values[key]
-	if !ok {
-		return "", ErrNotFound
-	}
-	return v.AsString()
-}
-
-// GetEncryptedString decorates GetString and decrypt its output with the given symmetric encryption key.
-func (m *Claims) GetEncryptedString(key string, encryptionKey []byte) (string, error) {
-	v, err := m.GetBytes(key)
-	if err != nil {
-		return "", err
-	}
-
-	decrypted, err := secretbox.DecryptStringWithKey(v, encryptionKey)
-	if err != nil {
-		return "", err
-	}
-
-	return string(decrypted), nil
-}
-
-// GetInt64 retrieves a value as an int64.
-// Returns ErrNotFound if the given key is missing.
-// Returns datamodel.ErrWrongKind if the value has the wrong type.
-func (m *Claims) GetInt64(key string) (int64, error) {
-	v, ok := m.Values[key]
-	if !ok {
-		return 0, ErrNotFound
-	}
-	return v.AsInt()
-}
-
-// GetFloat64 retrieves a value as a float64.
-// Returns ErrNotFound if the given key is missing.
-// Returns datamodel.ErrWrongKind if the value has the wrong type.
-func (m *Claims) GetFloat64(key string) (float64, error) {
-	v, ok := m.Values[key]
-	if !ok {
-		return 0, ErrNotFound
-	}
-	return v.AsFloat()
-}
-
-// GetBytes retrieves a value as a []byte.
-// Returns ErrNotFound if the given key is missing.
-// Returns datamodel.ErrWrongKind if the value has the wrong type.
-func (m *Claims) GetBytes(key string) ([]byte, error) {
-	v, ok := m.Values[key]
-	if !ok {
-		return nil, ErrNotFound
-	}
-	return v.AsBytes()
-}
-
-// GetEncryptedBytes decorates GetBytes and decrypt its output with the given symmetric encryption key.
-func (m *Claims) GetEncryptedBytes(key string, encryptionKey []byte) ([]byte, error) {
-	v, err := m.GetBytes(key)
-	if err != nil {
-		return nil, err
-	}
-
-	decrypted, err := secretbox.DecryptStringWithKey(v, encryptionKey)
-	if err != nil {
-		return nil, err
-	}
-
-	return decrypted, nil
-}
-
-// GetNode retrieves a value as a raw IPLD node.
-// Returns ErrNotFound if the given key is missing.
-func (m *Claims) GetNode(key string) (ipld.Node, error) {
-	v, ok := m.Values[key]
-	if !ok {
-		return nil, ErrNotFound
-	}
-	return v, nil
-}
-
-// Add adds a key/value pair in the claims set.
-// Accepted types for val are any CBOR compatible type, or directly IPLD values.
-func (m *Claims) Add(key string, val any) error {
-	if _, ok := m.Values[key]; ok {
-		return fmt.Errorf("duplicate key %q", key)
-	}
-
-	node, err := literal.Any(val)
-	if err != nil {
-		return err
-	}
-
-	m.Keys = append(m.Keys, key)
-	m.Values[key] = node
-
-	return nil
-}
-
-// AddEncrypted adds a key/value pair in the claims set.
-// The value is encrypted with the given encryptionKey.
-// Accepted types for the value are: string, []byte.
-// The ciphertext will be 40 bytes larger than the plaintext due to encryption overhead.
-func (m *Claims) AddEncrypted(key string, val any, encryptionKey []byte) error {
-	var encrypted []byte
-	var err error
-
-	switch val := val.(type) {
-	case string:
-		encrypted, err = secretbox.EncryptWithKey([]byte(val), encryptionKey)
-		if err != nil {
-			return err
-		}
-	case []byte:
-		encrypted, err = secretbox.EncryptWithKey(val, encryptionKey)
-		if err != nil {
-			return err
-		}
-	default:
-		return ErrNotEncryptable
-	}
-
-	return m.Add(key, encrypted)
-}
-
-type Iterator interface {
-	Iter() iter.Seq2[string, ipld.Node]
-}
-
-// Include merges the provided claims into the existing one.
-//
-// If duplicate keys are encountered, the new value is silently dropped
-// without causing an error.
-func (m *Claims) Include(other Iterator) {
-	for key, value := range other.Iter() {
-		if _, ok := m.Values[key]; ok {
-			// don't overwrite
-			continue
-		}
-		m.Values[key] = value
-		m.Keys = append(m.Keys, key)
-	}
-}
-
-// Len returns the number of key/values.
-func (m *Claims) Len() int {
-	return len(m.Values)
-}
-
-// Iter iterates over the claims key/values
-func (m *Claims) Iter() iter.Seq2[string, ipld.Node] {
-	return func(yield func(string, ipld.Node) bool) {
-		for _, key := range m.Keys {
-			if !yield(key, m.Values[key]) {
-				return
-			}
-		}
-	}
-}
-
-// Equals tells if two Claims hold the same key/values.
-func (m *Claims) Equals(other *Claims) bool {
-	if len(m.Keys) != len(other.Keys) {
-		return false
-	}
-	if len(m.Values) != len(other.Values) {
-		return false
-	}
-	for _, key := range m.Keys {
-		if !ipld.DeepEqual(m.Values[key], other.Values[key]) {
-			return false
-		}
-	}
-	return true
-}
-
-func (m *Claims) String() string {
-	sort.Strings(m.Keys)
-
-	buf := strings.Builder{}
-	buf.WriteString("{")
-
-	for key, node := range m.Values {
-		buf.WriteString("\n\t")
-		buf.WriteString(key)
-		buf.WriteString(": ")
-		buf.WriteString(strings.ReplaceAll(printer.Sprint(node), "\n", "\n\t"))
-		buf.WriteString(",")
-	}
-
-	if len(m.Values) > 0 {
-		buf.WriteString("\n")
-	}
-	buf.WriteString("}")
-
-	return buf.String()
-}
-
-// ReadOnly returns a read-only version of Claims.
-func (m *Claims) ReadOnly() ReadOnly {
-	return ReadOnly{claims: m}
-}
-
-// Clone makes a deep copy.
-func (m *Claims) Clone() *Claims {
-	res := &Claims{
-		Keys:   make([]string, len(m.Keys)),
-		Values: make(map[string]ipld.Node, len(m.Values)),
-	}
-	copy(res.Keys, m.Keys)
-	for k, v := range m.Values {
-		res.Values[k] = v
-	}
-	return res
-}

pkg/claims/claims_test.go

@@ -1,130 +0,0 @@
-package claims_test
-
-import (
-	"crypto/rand"
-	"maps"
-	"testing"
-
-	"github.com/ipld/go-ipld-prime"
-	"github.com/ipld/go-ipld-prime/node/basicnode"
-	"github.com/stretchr/testify/require"
-
-	"github.com/ucan-wg/go-ucan/pkg/claims"
-)
-
-func TestClaims_Add(t *testing.T) {
-	t.Parallel()
-
-	type Unsupported struct{}
-
-	t.Run("error if not primitive or Node", func(t *testing.T) {
-		t.Parallel()
-
-		err := (&claims.Claims{}).Add("invalid", &Unsupported{})
-		require.Error(t, err)
-	})
-
-	t.Run("encrypted claims", func(t *testing.T) {
-		t.Parallel()
-
-		key := make([]byte, 32)
-		_, err := rand.Read(key)
-		require.NoError(t, err)
-
-		m := claims.NewClaims()
-
-		// string encryption
-		err = m.AddEncrypted("secret", "hello world", key)
-		require.NoError(t, err)
-
-		_, err = m.GetString("secret")
-		require.Error(t, err) // the ciphertext is saved as []byte instead of string
-
-		decrypted, err := m.GetEncryptedString("secret", key)
-		require.NoError(t, err)
-		require.Equal(t, "hello world", decrypted)
-
-		// bytes encryption
-		originalBytes := make([]byte, 128)
-		_, err = rand.Read(originalBytes)
-		require.NoError(t, err)
-		err = m.AddEncrypted("secret-bytes", originalBytes, key)
-		require.NoError(t, err)
-
-		encryptedBytes, err := m.GetBytes("secret-bytes")
-		require.NoError(t, err)
-		require.NotEqual(t, originalBytes, encryptedBytes)
-
-		decryptedBytes, err := m.GetEncryptedBytes("secret-bytes", key)
-		require.NoError(t, err)
-		require.Equal(t, originalBytes, decryptedBytes)
-
-		// error cases
-		t.Run("error on unsupported type", func(t *testing.T) {
-			err := m.AddEncrypted("invalid", 123, key)
-			require.ErrorIs(t, err, claims.ErrNotEncryptable)
-		})
-
-		t.Run("error on invalid key size", func(t *testing.T) {
-			err := m.AddEncrypted("invalid", "test", []byte("short-key"))
-			require.Error(t, err)
-			require.Contains(t, err.Error(), "invalid key size")
-		})
-
-		t.Run("error on nil key", func(t *testing.T) {
-			err := m.AddEncrypted("invalid", "test", nil)
-			require.Error(t, err)
-			require.Contains(t, err.Error(), "encryption key is required")
-		})
-	})
-}
-
-func TestIterCloneEquals(t *testing.T) {
-	m := claims.NewClaims()
-
-	require.NoError(t, m.Add("foo", "bar"))
-	require.NoError(t, m.Add("baz", 1234))
-
-	expected := map[string]ipld.Node{
-		"foo": basicnode.NewString("bar"),
-		"baz": basicnode.NewInt(1234),
-	}
-
-	// claims -> iter
-	require.Equal(t, expected, maps.Collect(m.Iter()))
-
-	// readonly -> iter
-	ro := m.ReadOnly()
-	require.Equal(t, expected, maps.Collect(ro.Iter()))
-
-	// claims -> clone -> iter
-	clone := m.Clone()
-	require.Equal(t, expected, maps.Collect(clone.Iter()))
-
-	// readonly -> WriteableClone -> iter
-	wclone := ro.WriteableClone()
-	require.Equal(t, expected, maps.Collect(wclone.Iter()))
-
-	require.True(t, m.Equals(wclone))
-	require.True(t, ro.Equals(wclone.ReadOnly()))
-}
-
-func TestInclude(t *testing.T) {
-	m1 := claims.NewClaims()
-
-	require.NoError(t, m1.Add("samekey", "bar"))
-	require.NoError(t, m1.Add("baz", 1234))
-
-	m2 := claims.NewClaims()
-
-	require.NoError(t, m2.Add("samekey", "othervalue")) // check no overwrite
-	require.NoError(t, m2.Add("otherkey", 1234))
-
-	m1.Include(m2)
-
-	require.Equal(t, map[string]ipld.Node{
-		"samekey":  basicnode.NewString("bar"),
-		"baz":      basicnode.NewInt(1234),
-		"otherkey": basicnode.NewInt(1234),
-	}, maps.Collect(m1.Iter()))
-}

pkg/claims/readonly.go

@@ -1,64 +0,0 @@
-package claims
-
-import (
-	"iter"
-
-	"github.com/ipld/go-ipld-prime"
-)
-
-// ReadOnly wraps a Claims into a read-only facade.
-type ReadOnly struct {
-	claims *Claims
-}
-
-func (r ReadOnly) GetBool(key string) (bool, error) {
-	return r.claims.GetBool(key)
-}
-
-func (r ReadOnly) GetString(key string) (string, error) {
-	return r.claims.GetString(key)
-}
-
-func (r ReadOnly) GetEncryptedString(key string, encryptionKey []byte) (string, error) {
-	return r.claims.GetEncryptedString(key, encryptionKey)
-}
-
-func (r ReadOnly) GetInt64(key string) (int64, error) {
-	return r.claims.GetInt64(key)
-}
-
-func (r ReadOnly) GetFloat64(key string) (float64, error) {
-	return r.claims.GetFloat64(key)
-}
-
-func (r ReadOnly) GetBytes(key string) ([]byte, error) {
-	return r.claims.GetBytes(key)
-}
-
-func (r ReadOnly) GetEncryptedBytes(key string, encryptionKey []byte) ([]byte, error) {
-	return r.claims.GetEncryptedBytes(key, encryptionKey)
-}
-
-func (r ReadOnly) GetNode(key string) (ipld.Node, error) {
-	return r.claims.GetNode(key)
-}
-
-func (r ReadOnly) Len() int {
-	return r.claims.Len()
-}
-
-func (r ReadOnly) Iter() iter.Seq2[string, ipld.Node] {
-	return r.claims.Iter()
-}
-
-func (r ReadOnly) Equals(other ReadOnly) bool {
-	return r.claims.Equals(other.claims)
-}
-
-func (r ReadOnly) String() string {
-	return r.claims.String()
-}
-
-func (r ReadOnly) WriteableClone() *Claims {
-	return r.claims.Clone()
-}

token/attestation/attestation.go

@@ -1,210 +0,0 @@
-// Package attestation implements the UCAN [attestation] specification with
-// an immutable Token type as well as methods to convert the Token to and
-// from the [envelope]-enclosed, signed and DAG-CBOR-encoded form that
-// should most commonly be used for transport and storage.
-//
-// [envelope]: https://github.com/ucan-wg/spec#envelope
-// [attestation]: TBD
-package attestation
-
-import (
-	"encoding/base64"
-	"errors"
-	"fmt"
-	"strings"
-	"time"
-
-	"github.com/MetaMask/go-did-it"
-
-	"github.com/ucan-wg/go-ucan/pkg/claims"
-	"github.com/ucan-wg/go-ucan/pkg/meta"
-	"github.com/ucan-wg/go-ucan/token/internal/nonce"
-	"github.com/ucan-wg/go-ucan/token/internal/parse"
-)
-
-// Token is an immutable type that holds the fields of a UCAN attestation.
-type Token struct {
-	// The DID of the Invoker
-	issuer did.DID
-	// TODO: should this exist?
-	// audience did.DID
-
-	// Arbitrary Claims
-	claims *claims.Claims
-
-	// Arbitrary Metadata
-	meta *meta.Meta
-
-	// A unique, random nonce
-	nonce []byte
-	// The timestamp at which the Invocation becomes invalid
-	expiration *time.Time
-	// The timestamp at which the Invocation was created
-	issuedAt *time.Time
-}
-
-// New creates an attestation Token with the provided options.
-//
-// If no nonce is provided, a random 12-byte nonce is generated. Use the
-// WithNonce or WithEmptyNonce options to specify provide your own nonce
-// or to leave the nonce empty respectively.
-//
-// If no IssuedAt is provided, the current time is used. Use the
-// IssuedAt or WithIssuedAtIn Options to specify a different time
-// or the WithoutIssuedAt Option to clear the Token's IssuedAt field.
-//
-// With the exception of the WithMeta option, all others will overwrite
-// the previous contents of their target field.
-//
-// You can read it as "(Issuer - I) attest (arbitrary claim)".
-func New(iss did.DID, opts ...Option) (*Token, error) {
-	iat := time.Now()
-
-	tkn := Token{
-		issuer:   iss,
-		claims:   claims.NewClaims(),
-		meta:     meta.NewMeta(),
-		nonce:    nil,
-		issuedAt: &iat,
-	}
-
-	for _, opt := range opts {
-		if err := opt(&tkn); err != nil {
-			return nil, err
-		}
-	}
-
-	var err error
-	if len(tkn.nonce) == 0 {
-		tkn.nonce, err = nonce.Generate()
-		if err != nil {
-			return nil, err
-		}
-	}
-
-	if err := tkn.validate(); err != nil {
-		return nil, err
-	}
-
-	return &tkn, nil
-}
-
-// Issuer returns the did.DID representing the Token's issuer.
-func (t *Token) Issuer() did.DID {
-	return t.issuer
-}
-
-// Claims returns the Token's claims.
-func (t *Token) Claims() claims.ReadOnly {
-	return t.claims.ReadOnly()
-}
-
-// Meta returns the Token's metadata.
-func (t *Token) Meta() meta.ReadOnly {
-	return t.meta.ReadOnly()
-}
-
-// Nonce returns the random Nonce encapsulated in this Token.
-func (t *Token) Nonce() []byte {
-	return t.nonce
-}
-
-// Expiration returns the time at which the Token expires.
-func (t *Token) Expiration() *time.Time {
-	return t.expiration
-}
-
-// IssuedAt returns the time.Time at which the invocation token was
-// created.
-func (t *Token) IssuedAt() *time.Time {
-	return t.issuedAt
-}
-
-// IsValidNow verifies that the token can be used at the current time, based on expiration or "not before" fields.
-// This does NOT do any other kind of verifications.
-func (t *Token) IsValidNow() bool {
-	return t.IsValidAt(time.Now())
-}
-
-// IsValidAt verifies that the token can be used at the given time, based on expiration or "not before" fields.
-// This does NOT do any other kind of verifications.
-func (t *Token) IsValidAt(ti time.Time) bool {
-	if t.expiration != nil && ti.After(*t.expiration) {
-		return false
-	}
-	return true
-}
-
-func (t *Token) String() string {
-	var res strings.Builder
-
-	res.WriteString(fmt.Sprintf("Issuer: %s\n", t.Issuer()))
-	res.WriteString(fmt.Sprintf("Nonce: %s\n", base64.StdEncoding.EncodeToString(t.Nonce())))
-	res.WriteString(fmt.Sprintf("Meta: %s\n", t.Meta()))
-	res.WriteString(fmt.Sprintf("Expiration: %v\n", t.Expiration()))
-	res.WriteString(fmt.Sprintf("Issued At: %v\n", t.IssuedAt()))
-
-	return res.String()
-}
-
-func (t *Token) validate() error {
-	var errs error
-
-	requiredDID := func(id did.DID, fieldname string) {
-		if id == nil {
-			errs = errors.Join(errs, fmt.Errorf(`a valid did is required for %s: %s`, fieldname, id.String()))
-		}
-	}
-
-	requiredDID(t.issuer, "Issuer")
-
-	if len(t.nonce) < 12 {
-		errs = errors.Join(errs, fmt.Errorf("token nonce too small"))
-	}
-
-	return errs
-}
-
-// tokenFromModel build a decoded view of the raw IPLD data.
-// This function also serves as validation.
-func tokenFromModel(m tokenPayloadModel) (*Token, error) {
-	var (
-		tkn Token
-		err error
-	)
-
-	if tkn.issuer, err = did.Parse(m.Iss); err != nil {
-		return nil, fmt.Errorf("parse iss: %w", err)
-	}
-
-	tkn.claims = m.Claims
-	if tkn.claims == nil {
-		tkn.claims = claims.NewClaims()
-	}
-
-	tkn.meta = m.Meta
-	if tkn.meta == nil {
-		tkn.meta = meta.NewMeta()
-	}
-
-	if len(m.Nonce) == 0 {
-		return nil, fmt.Errorf("nonce is required")
-	}
-	tkn.nonce = m.Nonce
-
-	tkn.expiration, err = parse.OptionalTimestamp(m.Exp)
-	if err != nil {
-		return nil, fmt.Errorf("parse expiration: %w", err)
-	}
-
-	tkn.issuedAt, err = parse.OptionalTimestamp(m.Iat)
-	if err != nil {
-		return nil, fmt.Errorf("parse IssuedAt: %w", err)
-	}
-
-	if err := tkn.validate(); err != nil {
-		return nil, err
-	}
-
-	return &tkn, nil
-}

token/attestation/attestation.ipldsch

@@ -1,22 +0,0 @@
-type DID string
-
-# The Attestation payload
-type Payload struct {
-    # Issuer DID (sender)
-    iss DID
-    # Audience DID (receiver) TODO: should that exist?
-    # aud DID
-
-    # Arbitrary claims
-    claims optional {String: Any}
-
-    # Arbitrary Metadata
-    meta optional {String : Any}
-
-    # A unique, random nonce
-    nonce Bytes
-    # The timestamp at which the Invocation becomes invalid
-    exp nullable Int
-    # The Timestamp at which the Invocation was created
-    iat optional Int
-}

token/attestation/examples_test.go

@@ -1,132 +0,0 @@
-package attestation_test
-
-import (
-	"bytes"
-	"encoding/json"
-	"errors"
-	"fmt"
-	"time"
-
-	"github.com/MetaMask/go-did-it"
-	didkeyctl "github.com/MetaMask/go-did-it/controller/did-key"
-	"github.com/MetaMask/go-did-it/crypto/ed25519"
-	"github.com/ipld/go-ipld-prime"
-	"github.com/ipld/go-ipld-prime/codec/dagcbor"
-	"github.com/ipld/go-ipld-prime/codec/dagjson"
-	"github.com/ipld/go-ipld-prime/node/basicnode"
-
-	"github.com/ucan-wg/go-ucan/token/attestation"
-)
-
-func ExampleNew() {
-	privKey, iss, _, _, err := setupExampleNew()
-	if err != nil {
-		fmt.Println("failed to create setup:", err.Error())
-		return
-	}
-
-	att, err := attestation.New(iss,
-		attestation.WithClaim("claim1", "UCAN is great"),
-		attestation.WithMeta("env", "development"),
-		attestation.WithExpirationIn(time.Minute),
-		attestation.WithoutIssuedAt())
-	if err != nil {
-		fmt.Println("failed to create attestation:", err.Error())
-		return
-	}
-
-	// foo, _ := att.ToDagJson(privKey)
-	// os.WriteFile("testdata/new.dagjson", foo, 0666)
-	// fmt.Println(base64.StdEncoding.EncodeToString(privKey.ToBytes()))
-
-	data, cid, err := att.ToSealed(privKey)
-	if err != nil {
-		fmt.Println("failed to seal attestation:", err.Error())
-		return
-	}
-
-	json, err := prettyDAGJSON(data)
-	if err != nil {
-		fmt.Println("failed to pretty DAG-JSON:", err.Error())
-		return
-	}
-
-	fmt.Println("CID:", cid)
-	fmt.Println("Token (pretty DAG-JSON):")
-	fmt.Println(json)
-
-	// Expected CID and DAG-JSON output:
-	// CID: bafyreibm5vo6gk75oreefkg6xkrrfb4d5dgkccgmutirjgtzi5j45svjm4
-	// Token (pretty DAG-JSON):
-	// [
-	//  {
-	//    "/": {
-	//      "bytes": "ApuXUsUYhqostO2zfKZK50GW0gXYPtrlpoVA8EwGFdyYahQecOizVpl+9wy64aqk2rMP4Q0UEUKCTV0ONMdPAw"
-	//    }
-	//  },
-	//  {
-	//    "h": {
-	//      "/": {
-	//        "bytes": "NAHtAe0BE3E"
-	//      }
-	//    },
-	//    "ucan/att@tbd": {
-	//      "claims": {
-	//        "claim1": "UCAN is great"
-	//      },
-	//      "exp": 1767790971,
-	//      "iss": "did:key:z6Mkm4RzzBDfSHqmwV9dp5jFsLkVgKRYp1PhSj7VybCcLHC4",
-	//      "meta": {
-	//        "env": "development"
-	//      },
-	//      "nonce": {
-	//        "/": {
-	//          "bytes": "NjS8QPvft97jbtUG"
-	//        }
-	//      }
-	//    }
-	//  }
-	// ]
-}
-
-func prettyDAGJSON(data []byte) (string, error) {
-	var node ipld.Node
-
-	node, err := ipld.Decode(data, dagcbor.Decode)
-	if err != nil {
-		return "", err
-	}
-
-	jsonData, err := ipld.Encode(node, dagjson.Encode)
-	if err != nil {
-		return "", err
-	}
-
-	var out bytes.Buffer
-	if err := json.Indent(&out, jsonData, "", "  "); err != nil {
-		return "", err
-	}
-
-	return out.String(), nil
-}
-
-func setupExampleNew() (privKey ed25519.PrivateKey, iss did.DID, claims map[string]any, meta map[string]any, errs error) {
-	var err error
-
-	_, privKey, err = ed25519.GenerateKeyPair()
-	if err != nil {
-		errs = errors.Join(errs, fmt.Errorf("failed to generate Ed25519 keypair: %w", err))
-		return
-	}
-	iss = didkeyctl.FromPrivateKey(privKey)
-
-	claims = map[string]any{
-		"claim1": "UCAN is great",
-	}
-
-	meta = map[string]any{
-		"env": basicnode.NewString("development"),
-	}
-
-	return // WARNING: named return values
-}

token/attestation/ipld.go

@@ -1,227 +0,0 @@
-package attestation
-
-import (
-	"io"
-
-	"github.com/MetaMask/go-did-it"
-	"github.com/MetaMask/go-did-it/crypto"
-	"github.com/ipfs/go-cid"
-	"github.com/ipld/go-ipld-prime"
-	"github.com/ipld/go-ipld-prime/codec"
-	"github.com/ipld/go-ipld-prime/codec/dagcbor"
-	"github.com/ipld/go-ipld-prime/codec/dagjson"
-	"github.com/ipld/go-ipld-prime/datamodel"
-
-	"github.com/ucan-wg/go-ucan/token/internal/envelope"
-)
-
-// ToSealed wraps the attestation token in an envelope, generates the
-// signature, encodes the result to DAG-CBOR and calculates the CID of
-// the resulting binary data.
-func (t *Token) ToSealed(privKey crypto.PrivateKeySigningBytes) ([]byte, cid.Cid, error) {
-	data, err := t.ToDagCbor(privKey)
-	if err != nil {
-		return nil, cid.Undef, err
-	}
-
-	id, err := envelope.CIDFromBytes(data)
-	if err != nil {
-		return nil, cid.Undef, err
-	}
-
-	return data, id, nil
-}
-
-// ToSealedWriter is the same as ToSealed but accepts an io.Writer.
-func (t *Token) ToSealedWriter(w io.Writer, privKey crypto.PrivateKeySigningBytes) (cid.Cid, error) {
-	cidWriter := envelope.NewCIDWriter(w)
-
-	if err := t.ToDagCborWriter(cidWriter, privKey); err != nil {
-		return cid.Undef, err
-	}
-
-	return cidWriter.CID()
-}
-
-// FromSealed decodes the provided binary data from the DAG-CBOR format,
-// verifies that the envelope's signature is correct based on the public
-// key taken from the issuer (iss) field and calculates the CID of the
-// incoming data.
-func FromSealed(data []byte, resolvOpts ...did.ResolutionOption) (*Token, cid.Cid, error) {
-	tkn, err := FromDagCbor(data, resolvOpts...)
-	if err != nil {
-		return nil, cid.Undef, err
-	}
-
-	id, err := envelope.CIDFromBytes(data)
-	if err != nil {
-		return nil, cid.Undef, err
-	}
-
-	return tkn, id, nil
-}
-
-// FromSealedReader is the same as Unseal but accepts an io.Reader.
-func FromSealedReader(r io.Reader, resolvOpts ...did.ResolutionOption) (*Token, cid.Cid, error) {
-	cidReader := envelope.NewCIDReader(r)
-
-	tkn, err := FromDagCborReader(cidReader, resolvOpts...)
-	if err != nil {
-		return nil, cid.Undef, err
-	}
-
-	id, err := cidReader.CID()
-	if err != nil {
-		return nil, cid.Undef, err
-	}
-
-	return tkn, id, nil
-}
-
-// Encode marshals a Token to the format specified by the provided
-// codec.Encoder.
-func (t *Token) Encode(privKey crypto.PrivateKeySigningBytes, encFn codec.Encoder) ([]byte, error) {
-	node, err := t.toIPLD(privKey)
-	if err != nil {
-		return nil, err
-	}
-
-	return ipld.Encode(node, encFn)
-}
-
-// EncodeWriter is the same as Encode, but accepts an io.Writer.
-func (t *Token) EncodeWriter(w io.Writer, privKey crypto.PrivateKeySigningBytes, encFn codec.Encoder) error {
-	node, err := t.toIPLD(privKey)
-	if err != nil {
-		return err
-	}
-
-	return ipld.EncodeStreaming(w, node, encFn)
-}
-
-// ToDagCbor marshals the Token to the DAG-CBOR format.
-func (t *Token) ToDagCbor(privKey crypto.PrivateKeySigningBytes) ([]byte, error) {
-	return t.Encode(privKey, dagcbor.Encode)
-}
-
-// ToDagCborWriter is the same as ToDagCbor, but it accepts an io.Writer.
-func (t *Token) ToDagCborWriter(w io.Writer, privKey crypto.PrivateKeySigningBytes) error {
-	return t.EncodeWriter(w, privKey, dagcbor.Encode)
-}
-
-// ToDagJson marshals the Token to the DAG-JSON format.
-func (t *Token) ToDagJson(privKey crypto.PrivateKeySigningBytes) ([]byte, error) {
-	return t.Encode(privKey, dagjson.Encode)
-}
-
-// ToDagJsonWriter is the same as ToDagJson, but it accepts an io.Writer.
-func (t *Token) ToDagJsonWriter(w io.Writer, privKey crypto.PrivateKeySigningBytes) error {
-	return t.EncodeWriter(w, privKey, dagjson.Encode)
-}
-
-// Decode unmarshals the input data using the format specified by the
-// provided codec.Decoder into a Token.
-//
-// An error is returned if the conversion fails or if the resulting
-// Token is invalid.
-func Decode(b []byte, decFn codec.Decoder, resolvOpts ...did.ResolutionOption) (*Token, error) {
-	node, err := ipld.Decode(b, decFn)
-	if err != nil {
-		return nil, err
-	}
-	return FromIPLD(node, resolvOpts...)
-}
-
-// DecodeReader is the same as Decode, but accept an io.Reader.
-func DecodeReader(r io.Reader, decFn codec.Decoder, resolvOpts ...did.ResolutionOption) (*Token, error) {
-	node, err := ipld.DecodeStreaming(r, decFn)
-	if err != nil {
-		return nil, err
-	}
-	return FromIPLD(node, resolvOpts...)
-}
-
-// FromDagCbor unmarshals the input data into a Token.
-//
-// An error is returned if the conversion fails or if the resulting
-// Token is invalid.
-func FromDagCbor(data []byte, resolvOpts ...did.ResolutionOption) (*Token, error) {
-	pay, err := envelope.FromDagCbor[*tokenPayloadModel](data, resolvOpts...)
-	if err != nil {
-		return nil, err
-	}
-
-	tkn, err := tokenFromModel(*pay)
-	if err != nil {
-		return nil, err
-	}
-
-	return tkn, err
-}
-
-// FromDagCborReader is the same as FromDagCbor, but accept an io.Reader.
-func FromDagCborReader(r io.Reader, resolvOpts ...did.ResolutionOption) (*Token, error) {
-	return DecodeReader(r, dagcbor.Decode, resolvOpts...)
-}
-
-// FromDagJson unmarshals the input data into a Token.
-//
-// An error is returned if the conversion fails or if the resulting
-// Token is invalid.
-func FromDagJson(data []byte, resolvOpts ...did.ResolutionOption) (*Token, error) {
-	return Decode(data, dagjson.Decode, resolvOpts...)
-}
-
-// FromDagJsonReader is the same as FromDagJson, but accept an io.Reader.
-func FromDagJsonReader(r io.Reader, resolvOpts ...did.ResolutionOption) (*Token, error) {
-	return DecodeReader(r, dagjson.Decode, resolvOpts...)
-}
-
-// FromIPLD decode the given IPLD representation into a Token.
-func FromIPLD(node datamodel.Node, resolvOpts ...did.ResolutionOption) (*Token, error) {
-	pay, err := envelope.FromIPLD[*tokenPayloadModel](node, resolvOpts...)
-	if err != nil {
-		return nil, err
-	}
-
-	tkn, err := tokenFromModel(*pay)
-	if err != nil {
-		return nil, err
-	}
-
-	return tkn, err
-}
-
-func (t *Token) toIPLD(privKey crypto.PrivateKeySigningBytes) (datamodel.Node, error) {
-	var exp *int64
-	if t.expiration != nil {
-		u := t.expiration.Unix()
-		exp = &u
-	}
-
-	var iat *int64
-	if t.issuedAt != nil {
-		i := t.issuedAt.Unix()
-		iat = &i
-	}
-
-	model := &tokenPayloadModel{
-		Iss:    t.issuer.String(),
-		Claims: t.claims,
-		Meta:   t.meta,
-		Nonce:  t.nonce,
-		Exp:    exp,
-		Iat:    iat,
-	}
-
-	if len(model.Claims.Keys) == 0 {
-		model.Claims = nil
-	}
-
-	// seems like it's a requirement to have a null meta if there are no values?
-	if len(model.Meta.Keys) == 0 {
-		model.Meta = nil
-	}
-
-	return envelope.ToIPLD(privKey, model)
-}

token/attestation/ipld_test.go

@@ -1,35 +0,0 @@
-package attestation_test
-
-import (
-	"testing"
-	"time"
-
-	"github.com/stretchr/testify/assert"
-	"github.com/stretchr/testify/require"
-
-	"github.com/ucan-wg/go-ucan/token/attestation"
-)
-
-func TestSealUnsealRoundtrip(t *testing.T) {
-	t.Parallel()
-
-	privKey, iss, claims, meta, err := setupExampleNew()
-	require.NoError(t, err)
-
-	tkn1, err := attestation.New(iss,
-		attestation.WithClaimMap(claims),
-		attestation.WithMetaMap(meta),
-		attestation.WithExpirationIn(time.Minute),
-		attestation.WithoutIssuedAt(),
-	)
-	require.NoError(t, err)
-
-	data, cid1, err := tkn1.ToSealed(privKey)
-	require.NoError(t, err)
-
-	tkn2, cid2, err := attestation.FromSealed(data)
-	require.NoError(t, err)
-
-	assert.Equal(t, cid1, cid2)
-	assert.Equal(t, tkn1, tkn2)
-}

token/attestation/options.go

@@ -1,168 +0,0 @@
-package attestation
-
-import (
-	"time"
-)
-
-// Option is a type that allows optional fields to be set during the
-// creation of a Token.
-type Option func(*Token) error
-
-// WithClaim adds a key/value pair in the "claims" field.
-//
-// WithClaims can be used multiple times in the same call.
-// Accepted types for the value are: bool, string, int, int32, int64, []byte,
-// and ipld.Node.
-func WithClaim(key string, val any) Option {
-	return func(t *Token) error {
-		return t.claims.Add(key, val)
-	}
-}
-
-// WithClaimsMap adds all key/value pairs in the provided map to the
-// Token's "claims" field.
-//
-// WithClaimsMap can be used multiple times in the same call.
-// Accepted types for the value are: bool, string, int, int32, int64, []byte,
-// and ipld.Node.
-func WithClaimMap(m map[string]any) Option {
-	return func(t *Token) error {
-		for k, v := range m {
-			if err := t.claims.Add(k, v); err != nil {
-				return err
-			}
-		}
-		return nil
-	}
-}
-
-// WithEncryptedClaimsString adds a key/value pair in the "claims" field.
-// The string value is encrypted with the given aesKey.
-func WithEncryptedClaimsString(key, val string, encryptionKey []byte) Option {
-	return func(t *Token) error {
-		return t.claims.AddEncrypted(key, val, encryptionKey)
-	}
-}
-
-// WithEncryptedClaimsBytes adds a key/value pair in the "claims" field.
-// The []byte value is encrypted with the given aesKey.
-func WithEncryptedClaimsBytes(key string, val, encryptionKey []byte) Option {
-	return func(t *Token) error {
-		return t.claims.AddEncrypted(key, val, encryptionKey)
-	}
-}
-
-// WithMeta adds a key/value pair in the "meta" field.
-//
-// WithMeta can be used multiple times in the same call.
-// Accepted types for the value are: bool, string, int, int32, int64, []byte,
-// and ipld.Node.
-func WithMeta(key string, val any) Option {
-	return func(t *Token) error {
-		return t.meta.Add(key, val)
-	}
-}
-
-// WithMetaMap adds all key/value pairs in the provided map to the
-// Token's "meta" field.
-//
-// WithMetaMap can be used multiple times in the same call.
-// Accepted types for the value are: bool, string, int, int32, int64, []byte,
-// and ipld.Node.
-func WithMetaMap(m map[string]any) Option {
-	return func(t *Token) error {
-		for k, v := range m {
-			if err := t.meta.Add(k, v); err != nil {
-				return err
-			}
-		}
-		return nil
-	}
-}
-
-// WithEncryptedMetaString adds a key/value pair in the "meta" field.
-// The string value is encrypted with the given aesKey.
-func WithEncryptedMetaString(key, val string, encryptionKey []byte) Option {
-	return func(t *Token) error {
-		return t.meta.AddEncrypted(key, val, encryptionKey)
-	}
-}
-
-// WithEncryptedMetaBytes adds a key/value pair in the "meta" field.
-// The []byte value is encrypted with the given aesKey.
-func WithEncryptedMetaBytes(key string, val, encryptionKey []byte) Option {
-	return func(t *Token) error {
-		return t.meta.AddEncrypted(key, val, encryptionKey)
-	}
-}
-
-// WithNonce sets the Token's nonce with the given value.
-//
-// If this option is not used, a random 12-byte nonce is generated for
-// this required field.  If you truly want to create an invocation Token
-// without a nonce, use the WithEmptyNonce Option which will set the
-// nonce to an empty byte array.
-func WithNonce(nonce []byte) Option {
-	return func(t *Token) error {
-		t.nonce = nonce
-
-		return nil
-	}
-}
-
-// WithEmptyNonce sets the Token's nonce to an empty byte slice as
-// suggested by the UCAN spec for invocation tokens that represent
-// idempotent operations.
-func WithEmptyNonce() Option {
-	return func(t *Token) error {
-		t.nonce = []byte{}
-
-		return nil
-	}
-}
-
-// WithExpiration set's the Token's optional "expiration" field to the
-// value of the provided time.Time.
-func WithExpiration(exp time.Time) Option {
-	return func(t *Token) error {
-		exp = exp.Round(time.Second)
-		t.expiration = &exp
-
-		return nil
-	}
-}
-
-// WithExpirationIn set's the Token's optional "expiration" field to
-// Now() plus the given duration.
-func WithExpirationIn(after time.Duration) Option {
-	return WithExpiration(time.Now().Add(after))
-}
-
-// WithIssuedAt sets the Token's IssuedAt field to the provided
-// time.Time.
-//
-// If this Option is not provided, the invocation Token's iat field will
-// be set to the value of time.Now().  If you want to create an invocation
-// Token without this field being set, use the WithoutIssuedAt Option.
-func WithIssuedAt(iat time.Time) Option {
-	return func(t *Token) error {
-		t.issuedAt = &iat
-
-		return nil
-	}
-}
-
-// WithIssuedAtIn sets the Token's IssuedAt field to Now() plus the
-// given duration.
-func WithIssuedAtIn(after time.Duration) Option {
-	return WithIssuedAt(time.Now().Add(after))
-}
-
-// WithoutIssuedAt clears the Token's IssuedAt field.
-func WithoutIssuedAt() Option {
-	return func(t *Token) error {
-		t.issuedAt = nil
-
-		return nil
-	}
-}

token/attestation/schema.go

@@ -1,73 +0,0 @@
-package attestation
-
-import (
-	_ "embed"
-	"fmt"
-	"sync"
-
-	"github.com/ipld/go-ipld-prime"
-	"github.com/ipld/go-ipld-prime/node/bindnode"
-	"github.com/ipld/go-ipld-prime/schema"
-
-	"github.com/ucan-wg/go-ucan/pkg/claims"
-	"github.com/ucan-wg/go-ucan/pkg/meta"
-	"github.com/ucan-wg/go-ucan/token/internal/envelope"
-)
-
-// [Tag] is the string used as a key within the SigPayload that identifies
-// that the TokenPayload is an attestation.
-//
-// [Tag]: TODO: TBD
-const Tag = "ucan/att@tbd" // TODO: TBD
-
-//go:embed attestation.ipldsch
-var schemaBytes []byte
-
-var (
-	once      sync.Once
-	ts        *schema.TypeSystem
-	errSchema error
-)
-
-func mustLoadSchema() *schema.TypeSystem {
-	once.Do(func() {
-		ts, errSchema = ipld.LoadSchemaBytes(schemaBytes)
-	})
-	if errSchema != nil {
-		panic(fmt.Errorf("failed to load IPLD schema: %s", errSchema))
-	}
-	return ts
-}
-
-func payloadType() schema.Type {
-	return mustLoadSchema().TypeByName("Payload")
-}
-
-var _ envelope.Tokener = (*tokenPayloadModel)(nil)
-
-type tokenPayloadModel struct {
-	// The DID of the Invoker
-	Iss string
-
-	// Arbitrary claims
-	Claims *claims.Claims
-
-	// Arbitrary Metadata
-	Meta *meta.Meta
-
-	// A unique, random nonce
-	Nonce []byte
-	// The timestamp at which the Invocation becomes invalid
-	// optional: can be nil
-	Exp *int64
-	// The timestamp at which the Invocation was created
-	Iat *int64
-}
-
-func (e *tokenPayloadModel) Prototype() schema.TypedPrototype {
-	return bindnode.Prototype((*tokenPayloadModel)(nil), payloadType())
-}
-
-func (*tokenPayloadModel) Tag() string {
-	return Tag
-}

token/attestation/schema_test.go

@@ -1,89 +0,0 @@
-package attestation_test
-
-import (
-	"bytes"
-	_ "embed"
-	"encoding/base64"
-	"testing"
-
-	"github.com/MetaMask/go-did-it/crypto"
-	"github.com/MetaMask/go-did-it/crypto/ed25519"
-	"github.com/stretchr/testify/assert"
-	"github.com/stretchr/testify/require"
-
-	"github.com/ucan-wg/go-ucan/token/attestation"
-	"github.com/ucan-wg/go-ucan/token/internal/envelope"
-)
-
-//go:embed testdata/new.dagjson
-var newDagJson []byte
-
-const (
-	issuerPrivKeyCfg = "8bX3+HJxxlIGgNZ8yFG+t48oMGygEGyWD5Cy8ugeCIRksEIVyCabkuLVXbMZYj1lpXgL22Fok8nv52clGfEMXA=="
-	newCID           = "zdpuAyWCG3GWfebFME3e4oG926tzpJodw4WTa9VjBwqPNiVWF"
-)
-
-func TestSchemaRoundTrip(t *testing.T) {
-	t.Parallel()
-
-	privKey := privKey(t, issuerPrivKeyCfg)
-
-	t.Run("via buffers", func(t *testing.T) {
-		t.Parallel()
-
-		// format:    dagJson   -->   PayloadModel   -->   dagCbor   -->   PayloadModel   -->   dagJson
-		// function:      DecodeDagJson()           Seal()        Unseal()          EncodeDagJson()
-
-		p1, err := attestation.FromDagJson(newDagJson)
-		require.NoError(t, err)
-
-		cborBytes, id, err := p1.ToSealed(privKey)
-		require.NoError(t, err)
-		assert.Equal(t, newCID, envelope.CIDToBase58BTC(id))
-
-		p2, c2, err := attestation.FromSealed(cborBytes)
-		require.NoError(t, err)
-		assert.Equal(t, id, c2)
-
-		readJson, err := p2.ToDagJson(privKey)
-		require.NoError(t, err)
-
-		assert.JSONEq(t, string(newDagJson), string(readJson))
-	})
-
-	t.Run("via streaming", func(t *testing.T) {
-		t.Parallel()
-
-		buf := bytes.NewBuffer(newDagJson)
-
-		// format:    dagJson   -->   PayloadModel   -->   dagCbor   -->   PayloadModel   -->   dagJson
-		// function:      DecodeDagJson()           Seal()         Unseal()         EncodeDagJson()
-
-		p1, err := attestation.FromDagJsonReader(buf)
-		require.NoError(t, err)
-
-		cborBytes := &bytes.Buffer{}
-		id, err := p1.ToSealedWriter(cborBytes, privKey)
-		require.NoError(t, err)
-		assert.Equal(t, newCID, envelope.CIDToBase58BTC(id))
-
-		p2, c2, err := attestation.FromSealedReader(cborBytes)
-		require.NoError(t, err)
-		assert.Equal(t, envelope.CIDToBase58BTC(id), envelope.CIDToBase58BTC(c2))
-
-		readJson := &bytes.Buffer{}
-		require.NoError(t, p2.ToDagJsonWriter(readJson, privKey))
-
-		assert.JSONEq(t, string(newDagJson), readJson.String())
-	})
-}
-
-func privKey(t require.TestingT, privKeyCfg string) crypto.PrivateKeySigningBytes {
-	privBytes, err := base64.StdEncoding.DecodeString(privKeyCfg)
-	require.NoError(t, err)
-
-	privKey, err := ed25519.PrivateKeyFromBytes(privBytes)
-	require.NoError(t, err)
-
-	return privKey
-}

token/attestation/testdata/new.dagjson

@@ -1 +0,0 @@
-[{"/":{"bytes":"9lfCwLn+HqFGPNMbD9mIuMjhZarhZk1mOSq2eGLIBfRM6B5dtIftDh25TOG3qJrWRvZtvupd0az/PiVv/8zMCg"}},{"h":{"/":{"bytes":"NAHtAe0BE3E"}},"ucan/att@tbd":{"claims":{"claim1":"UCAN is great"},"exp":1767790946,"iss":"did:key:z6MkmEJhVC9xHMREKTw1HpPrwVh6fcUbJ8hoVEa3UQdP9sNs","meta":{"env":"development"},"nonce":{"/":{"bytes":"jPnfQhL20Eoq/8fu"}}}}]

token/delegation/delegation.go

@@ -238,7 +238,7 @@ func tokenFromModel(m tokenPayloadModel) (*Token, error) {
 
 	tkn.issuer, err = did.Parse(m.Iss)
 	if err != nil {
-		return nil, fmt.Errorf("parse iss: %w", err)
+		return nil, fmt.Errorf("parse issuer: %w", err)
 	}
 
 	if tkn.audience, err = did.Parse(m.Aud); err != nil {

token/delegation/delegationtest/generator/generator.go

@@ -71,6 +71,25 @@ type generator struct {
 	chains []proof
 }
 
+func (g *generator) createSelfDelegations(personas []didtest.Persona) error {
+	for _, persona := range personas {
+		_, err := g.createDelegation(newDelegationParams{
+			privKey: persona.PrivKey(),
+			aud:     persona.DID(),
+			cmd:     delegationtest.NominalCommand,
+			pol:     policytest.EmptyPolicy,
+			sub:     persona.DID(),
+			opts: []delegation.Option{
+				delegation.WithNonce(constantNonce),
+			},
+		}, persona.Name()+persona.Name(), noopVariant())
+		if err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
 func (g *generator) chainPersonas(personas []didtest.Persona, acc acc, vari variant) error {
 	acc.name += personas[0].Name()
 

token/delegation/delegationtest/generator/main.go

@@ -6,7 +6,11 @@ import (
 
 func main() {
 	gen := &generator{}
-	err := gen.chainPersonas(didtest.Personas(), acc{}, noopVariant())
+	err := gen.createSelfDelegations(didtest.Personas())
+	if err != nil {
+		panic(err)
+	}
+	err = gen.chainPersonas(didtest.Personas(), acc{}, noopVariant())
 	if err != nil {
 		panic(err)
 	}

token/delegation/delegationtest/token_gen.go

@@ -8,6 +8,48 @@ import (
 	"github.com/ucan-wg/go-ucan/token/delegation"
 )
 
+var (
+	TokenAliceAliceCID    = cid.MustParse("bafyreiddqsv5rrpcormtcs3dg7hzwjr2grxyyozc2f2surxdbnctdqpfzi")
+	TokenAliceAliceSealed = mustGetBundle(TokenAliceAliceCID).Sealed
+	TokenAliceAliceBundle = mustGetBundle(TokenAliceAliceCID)
+	TokenAliceAlice       = mustGetBundle(TokenAliceAliceCID).Decoded
+)
+
+var (
+	TokenBobBobCID    = cid.MustParse("bafyreid4dwdov4yijvnb7xxhcndsxifzw5yry4sm4frex6relttlnledo4")
+	TokenBobBobSealed = mustGetBundle(TokenBobBobCID).Sealed
+	TokenBobBobBundle = mustGetBundle(TokenBobBobCID)
+	TokenBobBob       = mustGetBundle(TokenBobBobCID).Decoded
+)
+
+var (
+	TokenCarolCarolCID    = cid.MustParse("bafyreiekuehdsubdfllqecsat4gsfveyqq6442ejuiqfsgu3tplrus5l3e")
+	TokenCarolCarolSealed = mustGetBundle(TokenCarolCarolCID).Sealed
+	TokenCarolCarolBundle = mustGetBundle(TokenCarolCarolCID)
+	TokenCarolCarol       = mustGetBundle(TokenCarolCarolCID).Decoded
+)
+
+var (
+	TokenDanDanCID    = cid.MustParse("bafyreigzd442yhyizbx54kd76ewxssh5owuxv26ziittnblnj4h3a555dm")
+	TokenDanDanSealed = mustGetBundle(TokenDanDanCID).Sealed
+	TokenDanDanBundle = mustGetBundle(TokenDanDanCID)
+	TokenDanDan       = mustGetBundle(TokenDanDanCID).Decoded
+)
+
+var (
+	TokenErinErinCID    = cid.MustParse("bafyreigl5lbogpzq7iyz6qkzhicv4zscu26j62k4ydgcqogdiqmks5tz7q")
+	TokenErinErinSealed = mustGetBundle(TokenErinErinCID).Sealed
+	TokenErinErinBundle = mustGetBundle(TokenErinErinCID)
+	TokenErinErin       = mustGetBundle(TokenErinErinCID).Decoded
+)
+
+var (
+	TokenFrankFrankCID    = cid.MustParse("bafyreic6hgmqf2vwszboldlqeobpy2plpkcmj4dhhug76akcnafb2pt6em")
+	TokenFrankFrankSealed = mustGetBundle(TokenFrankFrankCID).Sealed
+	TokenFrankFrankBundle = mustGetBundle(TokenFrankFrankCID)
+	TokenFrankFrank       = mustGetBundle(TokenFrankFrankCID).Decoded
+)
+
 var (
 	TokenAliceBobCID    = cid.MustParse("bafyreifa35rjstdm37cjudzs72ab22rnh5blny725khtapox63fnsj6pbe")
 	TokenAliceBobSealed = mustGetBundle(TokenAliceBobCID).Sealed
@@ -170,6 +212,12 @@ var (
 )
 
 var AllTokens = []*delegation.Token{
+	TokenAliceAlice,
+	TokenBobBob,
+	TokenCarolCarol,
+	TokenDanDan,
+	TokenErinErin,
+	TokenFrankFrank,
 	TokenAliceBob,
 	TokenBobCarol,
 	TokenCarolDan,
@@ -196,6 +244,12 @@ var AllTokens = []*delegation.Token{
 }
 
 var AllBundles = []delegation.Bundle{
+	TokenAliceAliceBundle,
+	TokenBobBobBundle,
+	TokenCarolCarolBundle,
+	TokenDanDanBundle,
+	TokenErinErinBundle,
+	TokenFrankFrankBundle,
 	TokenAliceBobBundle,
 	TokenBobCarolBundle,
 	TokenCarolDanBundle,
@@ -222,6 +276,12 @@ var AllBundles = []delegation.Bundle{
 }
 
 var cidToName = map[cid.Cid]string{
+	TokenAliceAliceCID:                       "TokenAliceAlice",
+	TokenBobBobCID:                           "TokenBobBob",
+	TokenCarolCarolCID:                       "TokenCarolCarol",
+	TokenDanDanCID:                           "TokenDanDan",
+	TokenErinErinCID:                         "TokenErinErin",
+	TokenFrankFrankCID:                       "TokenFrankFrank",
 	TokenAliceBobCID:                         "TokenAliceBob",
 	TokenBobCarolCID:                         "TokenBobCarol",
 	TokenCarolDanCID:                         "TokenCarolDan",

token/delegation/options.go

@@ -42,23 +42,6 @@ func WithMeta(key string, val any) Option {
 	}
 }
 
-// WithMetaMap adds all key/value pairs in the provided map to the
-// Token's "meta" field.
-//
-// WithMetaMap can be used multiple times in the same call.
-// Accepted types for the value are: bool, string, int, int32, int64, []byte,
-// and ipld.Node.
-func WithMetaMap(m map[string]any) Option {
-	return func(t *Token) error {
-		for k, v := range m {
-			if err := t.meta.Add(k, v); err != nil {
-				return err
-			}
-		}
-		return nil
-	}
-}
-
 // WithEncryptedMetaString adds a key/value pair in the "meta" field.
 // The string value is encrypted with the given key.
 // The ciphertext will be 40 bytes larger than the plaintext due to encryption overhead.

token/invocation/invocation.go

@@ -109,10 +109,23 @@ func New(iss did.DID, cmd command.Command, sub did.DID, prf []cid.Cid, opts ...O
 	return &tkn, nil
 }
 
+// NewSelfSigned is similar to New, but self-signs the invocation, and therefore does not require a proof.
+// It's similar to having an invocation with a delegation from the invoker to itself.
+// This can be useful in some protocols where the invoker is the same as the subject, or to prove ownership of a resource.
+//
+// You can read it as "(Issuer - I) executes (command) on itself".
+func NewSelfSigned(iss did.DID, cmd command.Command, opts ...Option) (*Token, error) {
+	return New(iss, cmd, iss, nil, opts...)
+}
+
+// ExecutionAllowed verifies that the invocation respects the rules and can be executed.
+// IMPORTANT: this function does NOT verify that the subject (and audience if set) makes sense in your context.
 func (t *Token) ExecutionAllowed(loader delegation.Loader) error {
 	return t.executionAllowed(loader, t.arguments)
 }
 
+// ExecutionAllowedWithArgsHook is the same as ExecutionAllowed, but allows to modify the arguments before verifying them.
+// IMPORTANT: this function does NOT verify that the subject (and audience if set) makes sense in your context.
 func (t *Token) ExecutionAllowedWithArgsHook(loader delegation.Loader, hook func(args args.ReadOnly) (*args.Args, error)) error {
 	newArgs, err := hook(t.arguments.ReadOnly())
 	if err != nil {
@@ -204,6 +217,11 @@ func (t *Token) Cause() *cid.Cid {
 	return t.cause
 }
 
+// IsSelfSigned returns true if the token is self-signed, ie it has the same issuer and subject.
+func (t *Token) IsSelfSigned() bool {
+	return t.issuer.Equal(t.subject)
+}
+
 // IsValidNow verifies that the token can be used at the current time, based on expiration or "not before" fields.
 // This does NOT do any other kind of verifications.
 func (t *Token) IsValidNow() bool {
@@ -276,7 +294,7 @@ func tokenFromModel(m tokenPayloadModel) (*Token, error) {
 	)
 
 	if tkn.issuer, err = did.Parse(m.Iss); err != nil {
-		return nil, fmt.Errorf("parse iss: %w", err)
+		return nil, fmt.Errorf("parse issuer: %w", err)
 	}
 
 	if tkn.subject, err = did.Parse(m.Sub); err != nil {

token/invocation/invocation_test.go

@@ -3,6 +3,7 @@ package invocation_test
 import (
 	_ "embed"
 	"testing"
+	"time"
 
 	"github.com/MetaMask/go-did-it/didtest"
 	"github.com/ipfs/go-cid"
@@ -18,144 +19,257 @@ import (
 //go:embed testdata/new.dagjson
 var newDagJson []byte
 
-const (
-	missingTknCIDStr = "bafyreigwypmw6eul6vadi6g6lnfbsfo2zck7gfzsbjoroqs3djhnzzc7mm"
-)
+//go:embed testdata/selfsigned.dagjson
+var selfsignedDagJson []byte
+
+const missingTknCIDStr = "bafyreigwypmw6eul6vadi6g6lnfbsfo2zck7gfzsbjoroqs3djhnzzc7mm"
 
 var emptyArguments = args.New()
 
 func TestToken_ExecutionAllowed(t *testing.T) {
-	t.Parallel()
+	for _, tc := range []struct {
+		name   string
+		issuer didtest.Persona
+		cmd    command.Command
+		args   *args.Args
+		proofs []cid.Cid
+		opts   []invocation.Option
+		err    error
+	}{
+		// Passes
+		{
+			name:   "passes - only root",
+			issuer: didtest.PersonaBob,
+			cmd:    delegationtest.NominalCommand,
+			args:   emptyArguments,
+			proofs: delegationtest.ProofAliceBob,
+			err:    nil,
+		},
+		{
+			name:   "passes - valid chain",
+			issuer: didtest.PersonaFrank,
+			cmd:    delegationtest.NominalCommand,
+			args:   emptyArguments,
+			proofs: delegationtest.ProofAliceBobCarolDanErinFrank,
+			err:    nil,
+		},
+		{
+			name:   "passes - proof chain attenuates command",
+			issuer: didtest.PersonaFrank,
+			cmd:    delegationtest.AttenuatedCommand,
+			args:   emptyArguments,
+			proofs: delegationtest.ProofAliceBobCarolDanErinFrank_ValidAttenuatedCommand,
+			err:    nil,
+		},
+		{
+			name:   "passes - invocation attenuates command",
+			issuer: didtest.PersonaFrank,
+			cmd:    delegationtest.AttenuatedCommand,
+			args:   emptyArguments,
+			proofs: delegationtest.ProofAliceBobCarolDanErinFrank,
+			err:    nil,
+		},
+		{
+			name:   "passes - arguments satisfy empty policy",
+			issuer: didtest.PersonaFrank,
+			cmd:    delegationtest.NominalCommand,
+			args:   policytest.SpecValidArguments,
+			proofs: delegationtest.ProofAliceBobCarolDanErinFrank,
+			err:    nil,
+		},
+		{
+			name:   "passes - arguments satisfy example policy",
+			issuer: didtest.PersonaFrank,
+			cmd:    delegationtest.NominalCommand,
+			args:   policytest.SpecValidArguments,
+			proofs: delegationtest.ProofAliceBobCarolDanErinFrank_ValidExamplePolicy,
+			err:    nil,
+		},
+		{
+			name:   "passes - self-signed invocation doesn't require proof",
+			issuer: didtest.PersonaAlice,
+			cmd:    delegationtest.NominalCommand,
+			args:   emptyArguments,
+			proofs: nil,
+			err:    nil,
+		},
+		{
+			name:   "passes - self-signed invocation accepts a delegation to itself",
+			issuer: didtest.PersonaAlice,
+			cmd:    delegationtest.NominalCommand,
+			args:   emptyArguments,
+			proofs: []cid.Cid{delegationtest.TokenAliceAliceCID},
+			err:    nil,
+		},
 
-	t.Run("passes - only root", func(t *testing.T) {
-		t.Parallel()
+		// Fails
+		{
+			name:   "fails - no proof",
+			issuer: didtest.PersonaCarol,
+			cmd:    delegationtest.NominalCommand,
+			args:   emptyArguments,
+			proofs: delegationtest.ProofEmpty,
+			err:    invocation.ErrNoProof,
+		},
+		{
+			name:   "fails - missing referenced delegation",
+			issuer: didtest.PersonaCarol,
+			cmd:    delegationtest.NominalCommand,
+			args:   emptyArguments,
+			proofs: []cid.Cid{cid.MustParse(missingTknCIDStr), delegationtest.TokenAliceBobCID},
+			err:    invocation.ErrMissingDelegation,
+		},
+		{
+			name:   "fails - referenced delegation expired",
+			issuer: didtest.PersonaFrank,
+			cmd:    delegationtest.NominalCommand,
+			args:   emptyArguments,
+			proofs: delegationtest.ProofAliceBobCarolDanErinFrank_InvalidExpired,
+			err:    invocation.ErrTokenInvalidNow,
+		},
+		{
+			name:   "fails - referenced delegation inactive",
+			issuer: didtest.PersonaFrank,
+			cmd:    delegationtest.NominalCommand,
+			args:   emptyArguments,
+			proofs: delegationtest.ProofAliceBobCarolDanErinFrank_InvalidInactive,
+			err:    invocation.ErrTokenInvalidNow,
+		},
+		{
+			name:   "fails - last (or only) delegation not root",
+			issuer: didtest.PersonaFrank,
+			cmd:    delegationtest.NominalCommand,
+			args:   emptyArguments,
+			proofs: []cid.Cid{delegationtest.TokenErinFrankCID, delegationtest.TokenDanErinCID, delegationtest.TokenCarolDanCID},
+			err:    invocation.ErrLastNotRoot,
+		},
+		{
+			name:   "fails - broken chain",
+			issuer: didtest.PersonaFrank,
+			cmd:    delegationtest.NominalCommand,
+			args:   emptyArguments,
+			proofs: []cid.Cid{delegationtest.TokenCarolDanCID, delegationtest.TokenAliceBobCID},
+			err:    invocation.ErrBrokenChain,
+		},
+		{
+			name:   "fails - first not issued to invoker",
+			issuer: didtest.PersonaFrank,
+			cmd:    delegationtest.NominalCommand,
+			args:   emptyArguments,
+			proofs: []cid.Cid{delegationtest.TokenBobCarolCID, delegationtest.TokenAliceBobCID},
+			err:    invocation.ErrBrokenChain,
+		},
+		{
+			name:   "fails - proof chain expands command",
+			issuer: didtest.PersonaFrank,
+			cmd:    delegationtest.NominalCommand,
+			args:   emptyArguments,
+			proofs: delegationtest.ProofAliceBobCarolDanErinFrank_InvalidExpandedCommand,
+			err:    invocation.ErrCommandNotCovered,
+		},
+		{
+			name:   "fails - invocation expands command",
+			issuer: didtest.PersonaFrank,
+			cmd:    delegationtest.ExpandedCommand,
+			args:   emptyArguments,
+			proofs: delegationtest.ProofAliceBobCarolDanErinFrank,
+			err:    invocation.ErrCommandNotCovered,
+		},
+		{
+			name:   "fails - inconsistent subject",
+			issuer: didtest.PersonaFrank,
+			cmd:    delegationtest.ExpandedCommand,
+			args:   emptyArguments,
+			proofs: delegationtest.ProofAliceBobCarolDanErinFrank_InvalidSubject,
+			err:    invocation.ErrWrongSub,
+		},
+		{
+			name:   "fails - arguments don't satisfy example policy",
+			issuer: didtest.PersonaFrank,
+			cmd:    delegationtest.NominalCommand,
+			args:   policytest.SpecInvalidArguments,
+			proofs: delegationtest.ProofAliceBobCarolDanErinFrank_ValidExamplePolicy,
+			err:    invocation.ErrPolicyNotSatisfied,
+		},
+		{
+			name:   "fails - self-signed invocation refuses a delegation to itself for a different DID",
+			issuer: didtest.PersonaAlice,
+			cmd:    delegationtest.NominalCommand,
+			args:   emptyArguments,
+			proofs: []cid.Cid{delegationtest.TokenBobBobCID},
+			err:    invocation.ErrWrongSub,
+		},
+	} {
+		t.Run(tc.name, func(t *testing.T) {
+			tc.opts = append(tc.opts, invocation.WithArguments(tc.args))
 
-		testPasses(t, didtest.PersonaBob, delegationtest.NominalCommand, emptyArguments, delegationtest.ProofAliceBob)
-	})
+			tkn, err := invocation.New(tc.issuer.DID(), tc.cmd, didtest.PersonaAlice.DID(), tc.proofs, tc.opts...)
+			require.NoError(t, err)
 
-	t.Run("passes - valid chain", func(t *testing.T) {
-		t.Parallel()
+			t.Log(tkn.String())
 
-		testPasses(t, didtest.PersonaFrank, delegationtest.NominalCommand, emptyArguments, delegationtest.ProofAliceBobCarolDanErinFrank)
-	})
+			err = tkn.ExecutionAllowed(delegationtest.GetDelegationLoader())
 
-	t.Run("passes - proof chain attenuates command", func(t *testing.T) {
-		t.Parallel()
+			if tc.err != nil {
+				require.ErrorIs(t, err, tc.err)
+			} else {
+				require.NoError(t, err)
+			}
+		})
+	}
+}
 
-		testPasses(t, didtest.PersonaFrank, delegationtest.AttenuatedCommand, emptyArguments, delegationtest.ProofAliceBobCarolDanErinFrank_ValidAttenuatedCommand)
-	})
+const (
+	nonce      = "6roDhGi0kiNriQAz7J3d+bOeoI/tj8ENikmQNbtjnD0"
+	subjectCmd = "/foo/bar"
+)
 
-	t.Run("passes - invocation attenuates command", func(t *testing.T) {
-		t.Parallel()
+func TestConstructors(t *testing.T) {
+	cmd, err := command.Parse(subjectCmd)
+	require.NoError(t, err)
 
-		testPasses(t, didtest.PersonaFrank, delegationtest.AttenuatedCommand, emptyArguments, delegationtest.ProofAliceBobCarolDanErinFrank)
-	})
+	iat, err := time.Parse(time.RFC3339, "2100-01-01T00:00:00Z")
+	require.NoError(t, err)
 
-	t.Run("passes - arguments satisfy empty policy", func(t *testing.T) {
-		t.Parallel()
+	exp, err := time.Parse(time.RFC3339, "2200-01-01T00:00:00Z")
+	require.NoError(t, err)
 
-		testPasses(t, didtest.PersonaFrank, delegationtest.NominalCommand, policytest.SpecValidArguments, delegationtest.ProofAliceBobCarolDanErinFrank)
-	})
-
-	t.Run("passes - arguments satify example policy", func(t *testing.T) {
-		t.Parallel()
-
-		testPasses(t, didtest.PersonaFrank, delegationtest.NominalCommand, policytest.SpecValidArguments, delegationtest.ProofAliceBobCarolDanErinFrank_ValidExamplePolicy)
-	})
-
-	t.Run("fails - no proof", func(t *testing.T) {
-		t.Parallel()
-
-		testFails(t, invocation.ErrNoProof, didtest.PersonaCarol, delegationtest.NominalCommand, emptyArguments, delegationtest.ProofEmpty)
-	})
-
-	t.Run("fails - missing referenced delegation", func(t *testing.T) {
-		t.Parallel()
-
-		missingTknCID, err := cid.Parse(missingTknCIDStr)
+	t.Run("New", func(t *testing.T) {
+		tkn, err := invocation.New(
+			didtest.PersonaAlice.DID(), cmd, didtest.PersonaBob.DID(),
+			delegationtest.ProofAliceBob,
+			invocation.WithNonce([]byte(nonce)),
+			invocation.WithIssuedAt(iat),
+			invocation.WithExpiration(exp),
+			invocation.WithArgument("foo", "bar"),
+			invocation.WithMeta("baz", 123),
+		)
 		require.NoError(t, err)
 
-		prf := []cid.Cid{missingTknCID, delegationtest.TokenAliceBobCID}
-		testFails(t, invocation.ErrMissingDelegation, didtest.PersonaCarol, delegationtest.NominalCommand, emptyArguments, prf)
+		require.False(t, tkn.IsSelfSigned())
+
+		data, err := tkn.ToDagJson(didtest.PersonaAlice.PrivKey())
+		require.NoError(t, err)
+
+		require.JSONEq(t, string(newDagJson), string(data))
 	})
 
-	t.Run("fails - referenced delegation expired", func(t *testing.T) {
-		t.Parallel()
+	t.Run("Self-Signed", func(t *testing.T) {
+		tkn, err := invocation.NewSelfSigned(
+			didtest.PersonaAlice.DID(), cmd,
+			invocation.WithNonce([]byte(nonce)),
+			invocation.WithIssuedAt(iat),
+			invocation.WithExpiration(exp),
+			invocation.WithArgument("foo", "bar"),
+			invocation.WithMeta("baz", 123),
+		)
+		require.NoError(t, err)
 
-		testFails(t, invocation.ErrTokenInvalidNow, didtest.PersonaFrank, delegationtest.NominalCommand, emptyArguments, delegationtest.ProofAliceBobCarolDanErinFrank_InvalidExpired)
+		require.True(t, tkn.IsSelfSigned())
 
+		data, err := tkn.ToDagJson(didtest.PersonaAlice.PrivKey())
+		require.NoError(t, err)
+
+		require.JSONEq(t, string(selfsignedDagJson), string(data))
 	})
-
-	t.Run("fails - referenced delegation inactive", func(t *testing.T) {
-		t.Parallel()
-
-		testFails(t, invocation.ErrTokenInvalidNow, didtest.PersonaFrank, delegationtest.NominalCommand, emptyArguments, delegationtest.ProofAliceBobCarolDanErinFrank_InvalidInactive)
-	})
-
-	t.Run("fails - last (or only) delegation not root", func(t *testing.T) {
-		t.Parallel()
-
-		prf := []cid.Cid{delegationtest.TokenErinFrankCID, delegationtest.TokenDanErinCID, delegationtest.TokenCarolDanCID}
-		testFails(t, invocation.ErrLastNotRoot, didtest.PersonaFrank, delegationtest.NominalCommand, emptyArguments, prf)
-	})
-
-	t.Run("fails - broken chain", func(t *testing.T) {
-		t.Parallel()
-
-		prf := []cid.Cid{delegationtest.TokenCarolDanCID, delegationtest.TokenAliceBobCID}
-		testFails(t, invocation.ErrBrokenChain, didtest.PersonaFrank, delegationtest.NominalCommand, emptyArguments, prf)
-	})
-
-	t.Run("fails - first not issued to invoker", func(t *testing.T) {
-		t.Parallel()
-
-		prf := []cid.Cid{delegationtest.TokenBobCarolCID, delegationtest.TokenAliceBobCID}
-		testFails(t, invocation.ErrBrokenChain, didtest.PersonaFrank, delegationtest.NominalCommand, emptyArguments, prf)
-	})
-
-	t.Run("fails - proof chain expands command", func(t *testing.T) {
-		t.Parallel()
-
-		testFails(t, invocation.ErrCommandNotCovered, didtest.PersonaFrank, delegationtest.NominalCommand, emptyArguments, delegationtest.ProofAliceBobCarolDanErinFrank_InvalidExpandedCommand)
-	})
-
-	t.Run("fails - invocation expands command", func(t *testing.T) {
-		t.Parallel()
-
-		testFails(t, invocation.ErrCommandNotCovered, didtest.PersonaFrank, delegationtest.ExpandedCommand, emptyArguments, delegationtest.ProofAliceBobCarolDanErinFrank)
-	})
-
-	t.Run("fails - inconsistent subject", func(t *testing.T) {
-		t.Parallel()
-
-		testFails(t, invocation.ErrWrongSub, didtest.PersonaFrank, delegationtest.ExpandedCommand, emptyArguments, delegationtest.ProofAliceBobCarolDanErinFrank_InvalidSubject)
-	})
-
-	t.Run("passes - arguments satisfy example policy", func(t *testing.T) {
-		t.Parallel()
-
-		testFails(t, invocation.ErrPolicyNotSatisfied, didtest.PersonaFrank, delegationtest.NominalCommand, policytest.SpecInvalidArguments, delegationtest.ProofAliceBobCarolDanErinFrank_ValidExamplePolicy)
-	})
-
-}
-
-func test(t *testing.T, persona didtest.Persona, cmd command.Command, args *args.Args, prf []cid.Cid, opts ...invocation.Option) error {
-	t.Helper()
-
-	opts = append(opts, invocation.WithArguments(args))
-
-	tkn, err := invocation.New(persona.DID(), cmd, didtest.PersonaAlice.DID(), prf, opts...)
-	require.NoError(t, err)
-
-	return tkn.ExecutionAllowed(delegationtest.GetDelegationLoader())
-}
-
-func testFails(t *testing.T, expErr error, persona didtest.Persona, cmd command.Command, args *args.Args, prf []cid.Cid, opts ...invocation.Option) {
-	err := test(t, persona, cmd, args, prf, opts...)
-	require.ErrorIs(t, err, expErr)
-}
-
-func testPasses(t *testing.T, persona didtest.Persona, cmd command.Command, args *args.Args, prf []cid.Cid, opts ...invocation.Option) {
-	err := test(t, persona, cmd, args, prf, opts...)
-	require.NoError(t, err)
 }

token/invocation/options.go

@@ -31,6 +31,7 @@ func WithArgument(key string, val any) Option {
 func WithArguments(args *args.Args) Option {
 	return func(t *Token) error {
 		t.arguments.Include(args)
+
 		return nil
 	}
 }
@@ -64,23 +65,6 @@ func WithMeta(key string, val any) Option {
 	}
 }
 
-// WithMetaMap adds all key/value pairs in the provided map to the
-// Token's "meta" field.
-//
-// WithMetaMap can be used multiple times in the same call.
-// Accepted types for the value are: bool, string, int, int32, int64, []byte,
-// and ipld.Node.
-func WithMetaMap(m map[string]any) Option {
-	return func(t *Token) error {
-		for k, v := range m {
-			if err := t.meta.Add(k, v); err != nil {
-				return err
-			}
-		}
-		return nil
-	}
-}
-
 // WithEncryptedMetaString adds a key/value pair in the "meta" field.
 // The string value is encrypted with the given aesKey.
 func WithEncryptedMetaString(key, val string, encryptionKey []byte) Option {

token/invocation/proof.go

@@ -18,11 +18,11 @@ import (
 //  1. When a token is read/unsealed from its containing envelope (`envelope` package):
 //     a. The envelope can be decoded.
 //     b. The envelope contains a Signature, VarsigHeader and Payload.
-//     c. The Payload contains an iss field that contains a valid `did:key`.
-//     d. The public key can be extracted from the `did:key`.
-//     e. The public key type is supported by go-ucan.
+//     c. The Payload contains an iss field that contains a valid DID.
+//     d. One or more public keys can be derived from the DID.
+//     e. One or more public keys are supported by go-ucan.
 //     f. The Signature can be decoded per the VarsigHeader.
-//     g. The SigPayload can be verified using the Signature and public key.
+//     g. The SigPayload can be verified using the Signature and one public key.
 //     h. The field key of the TokenPayload matches the expected tag.
 //
 //  2. When the token is created or passes step one (token constructor or decoder):
@@ -35,7 +35,7 @@ import (
 //     c. All the delegation must be active (nbf in the past or absent).
 //
 //  4. When the proof chain is being validated (verifyProofs below):
-//     a. There must be at least one delegation in the proof chain.
+//     a. Self-signed invocations (issuer == subject) are allowed and don't require further proof. Otherwise, proof is required.
 //     b. All referenced delegations must be available.
 //     c. The first proof must be issued to the Invoker (audience DID).
 //     d. The Issuer of each delegation must be the Audience in the next one.
@@ -51,8 +51,11 @@ import (
 // - principal alignment
 // - command alignment
 func (t *Token) verifyProofs(delegations []*delegation.Token) error {
-	// There must be at least one delegation referenced - 4a
-	if len(delegations) < 1 {
+	// Self-signed invocations (issuer == subject) are allowed and don't require further proof. Otherwise, proof is required. - 4a
+	if len(delegations) == 0 && t.issuer.Equal(t.subject) {
+		return nil
+	}
+	if len(delegations) == 0 {
 		return ErrNoProof
 	}
 

token/invocation/schema_test.go

@@ -2,6 +2,7 @@ package invocation_test
 
 import (
 	"bytes"
+	_ "embed"
 	"encoding/base64"
 	"testing"
 
@@ -14,9 +15,12 @@ import (
 	"github.com/ucan-wg/go-ucan/token/invocation"
 )
 
+//go:embed testdata/full_example.dagjson
+var fullExampleDagJson []byte
+
 const (
 	issuerPrivKeyCfg = "BeAgktAj8irGgWjp4PGk/fV67e5CcML/KRmmHSldco3etP5lRiuYQ+VVO/39ol3XXruJC8deSuBxoEXzgdYpYw=="
-	newCID           = "zdpuB1NjhETofEUp5iYzoHjSc2KKgZvSoT6FBaLMoVzzsxiR1"
+	fullExampleCID   = "zdpuB1NjhETofEUp5iYzoHjSc2KKgZvSoT6FBaLMoVzzsxiR1"
 )
 
 func TestSchemaRoundTrip(t *testing.T) {
@@ -30,12 +34,12 @@ func TestSchemaRoundTrip(t *testing.T) {
 		// format:    dagJson   -->   PayloadModel   -->   dagCbor   -->   PayloadModel   -->   dagJson
 		// function:      DecodeDagJson()           Seal()        Unseal()          EncodeDagJson()
 
-		p1, err := invocation.FromDagJson(newDagJson)
+		p1, err := invocation.FromDagJson(fullExampleDagJson)
 		require.NoError(t, err)
 
 		cborBytes, id, err := p1.ToSealed(privKey)
 		require.NoError(t, err)
-		assert.Equal(t, newCID, envelope.CIDToBase58BTC(id))
+		assert.Equal(t, fullExampleCID, envelope.CIDToBase58BTC(id))
 
 		p2, c2, err := invocation.FromSealed(cborBytes)
 		require.NoError(t, err)
@@ -44,13 +48,13 @@ func TestSchemaRoundTrip(t *testing.T) {
 		readJson, err := p2.ToDagJson(privKey)
 		require.NoError(t, err)
 
-		assert.JSONEq(t, string(newDagJson), string(readJson))
+		assert.JSONEq(t, string(fullExampleDagJson), string(readJson))
 	})
 
 	t.Run("via streaming", func(t *testing.T) {
 		t.Parallel()
 
-		buf := bytes.NewBuffer(newDagJson)
+		buf := bytes.NewBuffer(fullExampleDagJson)
 
 		// format:    dagJson   -->   PayloadModel   -->   dagCbor   -->   PayloadModel   -->   dagJson
 		// function:      DecodeDagJson()           Seal()         Unseal()         EncodeDagJson()
@@ -61,7 +65,7 @@ func TestSchemaRoundTrip(t *testing.T) {
 		cborBytes := &bytes.Buffer{}
 		id, err := p1.ToSealedWriter(cborBytes, privKey)
 		require.NoError(t, err)
-		assert.Equal(t, newCID, envelope.CIDToBase58BTC(id))
+		assert.Equal(t, fullExampleCID, envelope.CIDToBase58BTC(id))
 
 		p2, c2, err := invocation.FromSealedReader(cborBytes)
 		require.NoError(t, err)
@@ -70,7 +74,7 @@ func TestSchemaRoundTrip(t *testing.T) {
 		readJson := &bytes.Buffer{}
 		require.NoError(t, p2.ToDagJsonWriter(readJson, privKey))
 
-		assert.JSONEq(t, string(newDagJson), readJson.String())
+		assert.JSONEq(t, string(fullExampleDagJson), readJson.String())
 	})
 }
 

token/invocation/testdata/full_example.dagjson

@@ -0,0 +1 @@
+[{"/":{"bytes":"tRKNRahqwdyR6OpytuGIdcYI7HxXvKI5I594zznCLbN2C6WP5f8FIfIQlo0Nnqg4xFgKjJGAbIEVqeCZdib1Dw"}},{"h":{"/":{"bytes":"NAHtAe0BE3E"}},"ucan/inv@1.0.0-rc.1":{"args":{"headers":{"Content-Type":"application/json"},"payload":{"body":"UCAN is great","draft":true,"title":"UCAN for Fun and Profit","topics":["authz","journal"]},"uri":"https://example.com/blog/posts"},"cmd":"/crud/create","exp":1753965668,"iss":"did:key:z6MkuScdGeTmbWubyoWWpPmX9wkwdZAshkTcLKb1bf4Cyj8N","meta":{"env":"development","tags":["blog","post","pr#123"]},"nonce":{"/":{"bytes":"BBR5znl7VpRof4ac"}},"prf":[{"/":"bafyreigx3qxd2cndpe66j2mdssj773ecv7tqd7wovcnz5raguw6lj7sjoe"},{"/":"bafyreib34ira254zdqgehz6f2bhwme2ja2re3ltcalejv4x4tkcveujvpa"},{"/":"bafyreibkb66tpo2ixqx3fe5hmekkbuasrod6olt5bwm5u5pi726mduuwlq"}],"sub":"did:key:z6MkuQU8kqxCAUeurotHyrnMgkMUBtJN8ozYxkwctnop4zzB"}}]

token/invocation/testdata/new.dagjson

@@ -1 +1 @@
-[{"/":{"bytes":"tRKNRahqwdyR6OpytuGIdcYI7HxXvKI5I594zznCLbN2C6WP5f8FIfIQlo0Nnqg4xFgKjJGAbIEVqeCZdib1Dw"}},{"h":{"/":{"bytes":"NAHtAe0BE3E"}},"ucan/inv@1.0.0-rc.1":{"args":{"headers":{"Content-Type":"application/json"},"payload":{"body":"UCAN is great","draft":true,"title":"UCAN for Fun and Profit","topics":["authz","journal"]},"uri":"https://example.com/blog/posts"},"cmd":"/crud/create","exp":1753965668,"iss":"did:key:z6MkuScdGeTmbWubyoWWpPmX9wkwdZAshkTcLKb1bf4Cyj8N","meta":{"env":"development","tags":["blog","post","pr#123"]},"nonce":{"/":{"bytes":"BBR5znl7VpRof4ac"}},"prf":[{"/":"bafyreigx3qxd2cndpe66j2mdssj773ecv7tqd7wovcnz5raguw6lj7sjoe"},{"/":"bafyreib34ira254zdqgehz6f2bhwme2ja2re3ltcalejv4x4tkcveujvpa"},{"/":"bafyreibkb66tpo2ixqx3fe5hmekkbuasrod6olt5bwm5u5pi726mduuwlq"}],"sub":"did:key:z6MkuQU8kqxCAUeurotHyrnMgkMUBtJN8ozYxkwctnop4zzB"}}]
+[{"/":{"bytes":"8BxXBbXtPVoqn/z804w2w2gZH9m6kT55ivv7u2kxqptAfDcFzlRWBu3YKE9ijfIezpa79Btq5ja0PpqwjfSLAw"}},{"h":{"/":{"bytes":"NAHtAe0BE3E"}},"ucan/inv@1.0.0-rc.1":{"args":{"foo":"bar"},"cmd":"/foo/bar","exp":7258118400,"iat":4102444800,"iss":"did:key:z6MknUz1mSj4pvS6aUUHekCHdUPv7HBhDyDBZQ2W3Vujc5qC","meta":{"baz":123},"nonce":{"/":{"bytes":"NnJvRGhHaTBraU5yaVFBejdKM2QrYk9lb0kvdGo4RU5pa21RTmJ0am5EMA"}},"prf":[{"/":"bafyreifa35rjstdm37cjudzs72ab22rnh5blny725khtapox63fnsj6pbe"}],"sub":"did:key:z6Mkf4WtCwPDtamsZvBJA4eSVcE7vZuRPy5Skm4HaoQv81i1"}}]

token/invocation/testdata/selfsigned.dagjson

@@ -0,0 +1 @@
+[{"/":{"bytes":"ejXoQIdp3OGXewEkfQF4Z4Vd8c3H0XF319dsNh5DEP/2l9Nt9H1IhMpks1+HXoYFOKN3QmtxpPMoYmf/rhKaAQ"}},{"h":{"/":{"bytes":"NAHtAe0BE3E"}},"ucan/inv@1.0.0-rc.1":{"args":{"foo":"bar"},"cmd":"/foo/bar","exp":7258118400,"iat":4102444800,"iss":"did:key:z6MknUz1mSj4pvS6aUUHekCHdUPv7HBhDyDBZQ2W3Vujc5qC","meta":{"baz":123},"nonce":{"/":{"bytes":"NnJvRGhHaTBraU5yaVFBejdKM2QrYk9lb0kvdGo4RU5pa21RTmJ0am5EMA"}},"prf":[],"sub":"did:key:z6MknUz1mSj4pvS6aUUHekCHdUPv7HBhDyDBZQ2W3Vujc5qC"}}]

toolkit/client/proof.go

@@ -21,8 +21,7 @@ import (
 // Note: the returned delegation(s) don't have to match exactly the parameters, as long as they allow them.
 // Note: the implemented algorithm won't perform well with a large number of delegations.
 func FindProof(dlgs func() iter.Seq[*delegation.Bundle], issuer did.DID, cmd command.Command, subject did.DID) []cid.Cid {
-	// TODO: maybe that should be part of delegation.Token directly?
-	dlgMatch := func(dlg *delegation.Token, issuer did.DID, cmd command.Command, subject did.DID) bool {
+	continuePath := func(dlg *delegation.Token, issuer did.DID, cmd command.Command, subject did.DID) bool {
 		// The Subject of each delegation must equal the invocation's Subject (or Audience if defined). - 4f
 		if !dlg.Subject().Equal(subject) {
 			return false
@@ -47,7 +46,7 @@ func FindProof(dlgs func() iter.Seq[*delegation.Bundle], issuer did.DID, cmd com
 	var candidateLeaf []*delegation.Bundle
 
 	for bundle := range dlgs() {
-		if !dlgMatch(bundle.Decoded, issuer, cmd, subject) {
+		if !continuePath(bundle.Decoded, issuer, cmd, subject) {
 			continue
 		}
 		candidateLeaf = append(candidateLeaf, bundle)
@@ -83,7 +82,12 @@ func FindProof(dlgs func() iter.Seq[*delegation.Bundle], issuer did.DID, cmd com
 
 			// find parent delegation for our current delegation
 			for candidate := range dlgs() {
-				if !dlgMatch(candidate.Decoded, at.Decoded.Issuer(), at.Decoded.Command(), subject) {
+				// Prune the delegations that don't match the current proof.
+				if !continuePath(candidate.Decoded, at.Decoded.Issuer(), at.Decoded.Command(), subject) {
+					continue
+				}
+				// Prune the self-delegations as they can't get us closer to what we are looking for.
+				if candidate.Decoded.Issuer().Equal(candidate.Decoded.Audience()) {
 					continue
 				}
 

toolkit/client/proof_test.go

@@ -4,7 +4,9 @@ import (
 	"iter"
 	"testing"
 
+	"github.com/MetaMask/go-did-it"
 	"github.com/MetaMask/go-did-it/didtest"
+	"github.com/ipfs/go-cid"
 	"github.com/stretchr/testify/require"
 
 	"github.com/ucan-wg/go-ucan/pkg/command"
@@ -23,17 +25,76 @@ func TestFindProof(t *testing.T) {
 		}
 	}
 
-	require.Equal(t, delegationtest.ProofAliceBob,
-		FindProof(dlgs, didtest.PersonaBob.DID(), delegationtest.NominalCommand, didtest.PersonaAlice.DID()))
-	require.Equal(t, delegationtest.ProofAliceBobCarol,
-		FindProof(dlgs, didtest.PersonaCarol.DID(), delegationtest.NominalCommand, didtest.PersonaAlice.DID()))
-	require.Equal(t, delegationtest.ProofAliceBobCarolDan,
-		FindProof(dlgs, didtest.PersonaDan.DID(), delegationtest.NominalCommand, didtest.PersonaAlice.DID()))
-	require.Equal(t, delegationtest.ProofAliceBobCarolDanErin,
-		FindProof(dlgs, didtest.PersonaErin.DID(), delegationtest.NominalCommand, didtest.PersonaAlice.DID()))
-	require.Equal(t, delegationtest.ProofAliceBobCarolDanErinFrank,
-		FindProof(dlgs, didtest.PersonaFrank.DID(), delegationtest.NominalCommand, didtest.PersonaAlice.DID()))
+	for _, tc := range []struct {
+		name     string
+		issuer   did.DID
+		command  command.Command
+		subject  did.DID
+		expected []cid.Cid
+	}{
+		// Passes
+		{
+			name:     "Alice --> Alice (self-delegation)",
+			issuer:   didtest.PersonaAlice.DID(),
+			command:  delegationtest.NominalCommand,
+			subject:  didtest.PersonaAlice.DID(),
+			expected: []cid.Cid{delegationtest.TokenAliceAliceCID},
+		},
+		{
+			name:     "Alice --> Bob",
+			issuer:   didtest.PersonaBob.DID(),
+			command:  delegationtest.NominalCommand,
+			subject:  didtest.PersonaAlice.DID(),
+			expected: delegationtest.ProofAliceBob,
+		},
+		{
+			name:     "Alice --> Bob --> Carol",
+			issuer:   didtest.PersonaCarol.DID(),
+			command:  delegationtest.NominalCommand,
+			subject:  didtest.PersonaAlice.DID(),
+			expected: delegationtest.ProofAliceBobCarol,
+		},
+		{
+			name:     "Alice --> Bob --> Carol --> Dan",
+			issuer:   didtest.PersonaDan.DID(),
+			command:  delegationtest.NominalCommand,
+			subject:  didtest.PersonaAlice.DID(),
+			expected: delegationtest.ProofAliceBobCarolDan,
+		},
+		{
+			name:     "Alice --> Bob --> Carol --> Dan --> Erin",
+			issuer:   didtest.PersonaErin.DID(),
+			command:  delegationtest.NominalCommand,
+			subject:  didtest.PersonaAlice.DID(),
+			expected: delegationtest.ProofAliceBobCarolDanErin,
+		},
+		{
+			name:     "Alice --> Bob --> Carol --> Dan --> Erin --> Frank",
+			issuer:   didtest.PersonaFrank.DID(),
+			command:  delegationtest.NominalCommand,
+			subject:  didtest.PersonaAlice.DID(),
+			expected: delegationtest.ProofAliceBobCarolDanErinFrank,
+		},
 
-	// wrong command
-	require.Empty(t, FindProof(dlgs, didtest.PersonaBob.DID(), command.New("foo"), didtest.PersonaAlice.DID()))
+		// Fails
+		{
+			name:     "wrong command",
+			issuer:   didtest.PersonaBob.DID(),
+			command:  command.New("foo"),
+			subject:  didtest.PersonaAlice.DID(),
+			expected: nil,
+		},
+		{
+			name:     "wrong subject",
+			issuer:   didtest.PersonaBob.DID(),
+			command:  delegationtest.NominalCommand,
+			subject:  didtest.PersonaDan.DID(),
+			expected: nil,
+		},
+	} {
+		t.Run(tc.name, func(t *testing.T) {
+			res := FindProof(dlgs, tc.issuer, tc.command, tc.subject)
+			require.Equal(t, tc.expected, res)
+		})
+	}
 }