1package ed25519
 2
 3import (
 4	"crypto/rand"
 5	"encoding/asn1"
 6
 7	"github.com/cloudflare/circl/sign"
 8)
 9
10var sch sign.Scheme = &scheme{}
11
12// Scheme returns a signature interface.
13func Scheme() sign.Scheme { return sch }
14
15type scheme struct{}
16
17func (*scheme) Name() string          { return "Ed25519" }
18func (*scheme) PublicKeySize() int    { return PublicKeySize }
19func (*scheme) PrivateKeySize() int   { return PrivateKeySize }
20func (*scheme) SignatureSize() int    { return SignatureSize }
21func (*scheme) SeedSize() int         { return SeedSize }
22func (*scheme) TLSIdentifier() uint   { return 0x0807 }
23func (*scheme) SupportsContext() bool { return false }
24func (*scheme) Oid() asn1.ObjectIdentifier {
25	return asn1.ObjectIdentifier{1, 3, 101, 112}
26}
27
28func (*scheme) GenerateKey() (sign.PublicKey, sign.PrivateKey, error) {
29	return GenerateKey(rand.Reader)
30}
31
32func (*scheme) Sign(
33	sk sign.PrivateKey,
34	message []byte,
35	opts *sign.SignatureOpts,
36) []byte {
37	priv, ok := sk.(PrivateKey)
38	if !ok {
39		panic(sign.ErrTypeMismatch)
40	}
41	if opts != nil && opts.Context != "" {
42		panic(sign.ErrContextNotSupported)
43	}
44	return Sign(priv, message)
45}
46
47func (*scheme) Verify(
48	pk sign.PublicKey,
49	message, signature []byte,
50	opts *sign.SignatureOpts,
51) bool {
52	pub, ok := pk.(PublicKey)
53	if !ok {
54		panic(sign.ErrTypeMismatch)
55	}
56	if opts != nil {
57		if opts.Context != "" {
58			panic(sign.ErrContextNotSupported)
59		}
60	}
61	return Verify(pub, message, signature)
62}
63
64func (*scheme) DeriveKey(seed []byte) (sign.PublicKey, sign.PrivateKey) {
65	privateKey := NewKeyFromSeed(seed)
66	publicKey := make(PublicKey, PublicKeySize)
67	copy(publicKey, privateKey[SeedSize:])
68	return publicKey, privateKey
69}
70
71func (*scheme) UnmarshalBinaryPublicKey(buf []byte) (sign.PublicKey, error) {
72	if len(buf) < PublicKeySize {
73		return nil, sign.ErrPubKeySize
74	}
75	pub := make(PublicKey, PublicKeySize)
76	copy(pub, buf[:PublicKeySize])
77	return pub, nil
78}
79
80func (*scheme) UnmarshalBinaryPrivateKey(buf []byte) (sign.PrivateKey, error) {
81	if len(buf) < PrivateKeySize {
82		return nil, sign.ErrPrivKeySize
83	}
84	priv := make(PrivateKey, PrivateKeySize)
85	copy(priv, buf[:PrivateKeySize])
86	return priv, nil
87}