aboutsummaryrefslogtreecommitdiffstats
path: root/identity/key.go
blob: 8dd5e8c12f51007ffc5cd3e3834ef9725b42021f (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
package identity

import (
	"bytes"
	"encoding/json"
	"fmt"
	"io"
	"strings"
	"time"

	"github.com/pkg/errors"
	"golang.org/x/crypto/openpgp"
	"golang.org/x/crypto/openpgp/armor"
	"golang.org/x/crypto/openpgp/packet"

	"github.com/MichaelMure/git-bug/repository"
)

type Key struct {
	public  *packet.PublicKey
	private *packet.PrivateKey
}

// GenerateKey generate a keypair (public+private)
func GenerateKey() *Key {
	entity, err := openpgp.NewEntity("", "", "", &packet.Config{
		// The armored format doesn't include the creation time, which makes the round-trip data not being fully equal.
		// We don't care about the creation time so we can set it to the zero value.
		Time: func() time.Time {
			return time.Time{}
		},
	})
	if err != nil {
		panic(err)
	}
	return &Key{
		public:  entity.PrimaryKey,
		private: entity.PrivateKey,
	}
}

// generatePublicKey generate only a public key (only useful for testing)
// See GenerateKey for the details.
func generatePublicKey() *Key {
	k := GenerateKey()
	k.private = nil
	return k
}

func (k *Key) MarshalJSON() ([]byte, error) {
	var buf bytes.Buffer
	w, err := armor.Encode(&buf, openpgp.PublicKeyType, nil)
	if err != nil {
		return nil, err
	}
	err = k.public.Serialize(w)
	if err != nil {
		return nil, err
	}
	err = w.Close()
	if err != nil {
		return nil, err
	}
	return json.Marshal(buf.String())
}

func (k *Key) UnmarshalJSON(data []byte) error {
	var armored string
	err := json.Unmarshal(data, &armored)
	if err != nil {
		return err
	}

	block, err := armor.Decode(strings.NewReader(armored))
	if err == io.EOF {
		return fmt.Errorf("no armored data found")
	}
	if err != nil {
		return err
	}

	if block.Type != openpgp.PublicKeyType {
		return fmt.Errorf("invalid key type")
	}

	reader := packet.NewReader(block.Body)
	p, err := reader.Next()
	if err != nil {
		return errors.Wrap(err, "failed to read public key packet")
	}

	public, ok := p.(*packet.PublicKey)
	if !ok {
		return errors.New("got no packet.publicKey")
	}

	// The armored format doesn't include the creation time, which makes the round-trip data not being fully equal.
	// We don't care about the creation time so we can set it to the zero value.
	public.CreationTime = time.Time{}

	k.public = public
	return nil
}

func (k *Key) Validate() error {
	if k.public == nil {
		return fmt.Errorf("nil public key")
	}
	if !k.public.CanSign() {
		return fmt.Errorf("public key can't sign")
	}

	if k.private != nil {
		if !k.private.CanSign() {
			return fmt.Errorf("private key can't sign")
		}
	}

	return nil
}

func (k *Key) Clone() *Key {
	clone := &Key{}

	pub := *k.public
	clone.public = &pub

	if k.private != nil {
		priv := *k.private
		clone.private = &priv
	}

	return clone
}

func (k *Key) EnsurePrivateKey(repo repository.RepoKeyring) error {
	if k.private != nil {
		return nil
	}

	// item, err := repo.Keyring().Get(k.Fingerprint())
	// if err != nil {
	// 	return fmt.Errorf("no private key found for %s", k.Fingerprint())
	// }
	//

	panic("TODO")
}

func (k *Key) Fingerprint() string {
	return string(k.public.Fingerprint[:])
}

func (k *Key) PGPEntity() *openpgp.Entity {
	return &openpgp.Entity{
		PrimaryKey: k.public,
		PrivateKey: k.private,
	}
}

var _ openpgp.KeyRing = &PGPKeyring{}

// PGPKeyring implement a openpgp.KeyRing from an slice of Key
type PGPKeyring []*Key

func (pk PGPKeyring) KeysById(id uint64) []openpgp.Key {
	var result []openpgp.Key
	for _, key := range pk {
		if key.public.KeyId == id {
			result = append(result, openpgp.Key{
				PublicKey:  key.public,
				PrivateKey: key.private,
			})
		}
	}
	return result
}

func (pk PGPKeyring) KeysByIdUsage(id uint64, requiredUsage byte) []openpgp.Key {
	// the only usage we care about is the ability to sign, which all keys should already be capable of
	return pk.KeysById(id)
}

func (pk PGPKeyring) DecryptionKeys() []openpgp.Key {
	result := make([]openpgp.Key, len(pk))
	for i, key := range pk {
		result[i] = openpgp.Key{
			PublicKey:  key.public,
			PrivateKey: key.private,
		}
	}
	return result
}