aboutsummaryrefslogtreecommitdiffstats
path: root/models/ssh_key.go
blob: 9365fab1ab833676938b5f5699a6f3b23c12db65 (plain)
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
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
// Copyright 2014 The Gogs Authors. All rights reserved.
// Use of this source code is governed by a MIT-style
// license that can be found in the LICENSE file.

package models

import (
	"bufio"
	"encoding/base64"
	"encoding/binary"
	"errors"
	"fmt"
	"io/ioutil"
	"math/big"
	"os"
	"path/filepath"
	"strings"
	"sync"
	"time"

	"github.com/Unknwon/com"
	"github.com/go-xorm/xorm"
	"golang.org/x/crypto/ssh"

	"code.gitea.io/gitea/modules/log"
	"code.gitea.io/gitea/modules/process"
	"code.gitea.io/gitea/modules/setting"
)

const (
	tplCommentPrefix = `# gitea public key`
	tplPublicKey     = tplCommentPrefix + "\n" + `command="%s serv key-%d --config='%s'",no-port-forwarding,no-X11-forwarding,no-agent-forwarding,no-pty %s` + "\n"
)

var sshOpLocker sync.Mutex

// KeyType specifies the key type
type KeyType int

const (
	// KeyTypeUser specifies the user key
	KeyTypeUser = iota + 1
	// KeyTypeDeploy specifies the deploy key
	KeyTypeDeploy
)

// PublicKey represents a user or deploy SSH public key.
type PublicKey struct {
	ID          int64      `xorm:"pk autoincr"`
	OwnerID     int64      `xorm:"INDEX NOT NULL"`
	Name        string     `xorm:"NOT NULL"`
	Fingerprint string     `xorm:"NOT NULL"`
	Content     string     `xorm:"TEXT NOT NULL"`
	Mode        AccessMode `xorm:"NOT NULL DEFAULT 2"`
	Type        KeyType    `xorm:"NOT NULL DEFAULT 1"`

	Created           time.Time `xorm:"-"`
	CreatedUnix       int64     `xorm:"created"`
	Updated           time.Time `xorm:"-"`
	UpdatedUnix       int64     `xorm:"updated"`
	HasRecentActivity bool      `xorm:"-"`
	HasUsed           bool      `xorm:"-"`
}

// AfterLoad is invoked from XORM after setting the values of all fields of this object.
func (key *PublicKey) AfterLoad() {
	key.Created = time.Unix(key.CreatedUnix, 0).Local()
	key.Updated = time.Unix(key.UpdatedUnix, 0).Local()
	key.HasUsed = key.Updated.After(key.Created)
	key.HasRecentActivity = key.Updated.Add(7 * 24 * time.Hour).After(time.Now())
}

// OmitEmail returns content of public key without email address.
func (key *PublicKey) OmitEmail() string {
	return strings.Join(strings.Split(key.Content, " ")[:2], " ")
}

// AuthorizedString returns formatted public key string for authorized_keys file.
func (key *PublicKey) AuthorizedString() string {
	return fmt.Sprintf(tplPublicKey, setting.AppPath, key.ID, setting.CustomConf, key.Content)
}

func extractTypeFromBase64Key(key string) (string, error) {
	b, err := base64.StdEncoding.DecodeString(key)
	if err != nil || len(b) < 4 {
		return "", fmt.Errorf("invalid key format: %v", err)
	}

	keyLength := int(binary.BigEndian.Uint32(b))
	if len(b) < 4+keyLength {
		return "", fmt.Errorf("invalid key format: not enough length %d", keyLength)
	}

	return string(b[4 : 4+keyLength]), nil
}

// parseKeyString parses any key string in OpenSSH or SSH2 format to clean OpenSSH string (RFC4253).
func parseKeyString(content string) (string, error) {
	// Transform all legal line endings to a single "\n".
	content = strings.NewReplacer("\r\n", "\n", "\r", "\n").Replace(content)
	// remove trailing newline (and beginning spaces too)
	content = strings.TrimSpace(content)
	lines := strings.Split(content, "\n")

	var keyType, keyContent, keyComment string

	if len(lines) == 1 {
		// Parse OpenSSH format.
		parts := strings.SplitN(lines[0], " ", 3)
		switch len(parts) {
		case 0:
			return "", errors.New("empty key")
		case 1:
			keyContent = parts[0]
		case 2:
			keyType = parts[0]
			keyContent = parts[1]
		default:
			keyType = parts[0]
			keyContent = parts[1]
			keyComment = parts[2]
		}

		// If keyType is not given, extract it from content. If given, validate it.
		t, err := extractTypeFromBase64Key(keyContent)
		if err != nil {
			return "", fmt.Errorf("extractTypeFromBase64Key: %v", err)
		}
		if len(keyType) == 0 {
			keyType = t
		} else if keyType != t {
			return "", fmt.Errorf("key type and content does not match: %s - %s", keyType, t)
		}
	} else {
		// Parse SSH2 file format.
		continuationLine := false

		for _, line := range lines {
			// Skip lines that:
			// 1) are a continuation of the previous line,
			// 2) contain ":" as that are comment lines
			// 3) contain "-" as that are begin and end tags
			if continuationLine || strings.ContainsAny(line, ":-") {
				continuationLine = strings.HasSuffix(line, "\\")
			} else {
				keyContent = keyContent + line
			}
		}

		t, err := extractTypeFromBase64Key(keyContent)
		if err != nil {
			return "", fmt.Errorf("extractTypeFromBase64Key: %v", err)
		}
		keyType = t
	}
	return keyType + " " + keyContent + " " + keyComment, nil
}

// writeTmpKeyFile writes key content to a temporary file
// and returns the name of that file, along with any possible errors.
func writeTmpKeyFile(content string) (string, error) {
	tmpFile, err := ioutil.TempFile(setting.SSH.KeyTestPath, "gitea_keytest")
	if err != nil {
		return "", fmt.Errorf("TempFile: %v", err)
	}
	defer tmpFile.Close()

	if _, err = tmpFile.WriteString(content); err != nil {
		return "", fmt.Errorf("WriteString: %v", err)
	}
	return tmpFile.Name(), nil
}

// SSHKeyGenParsePublicKey extracts key type and length using ssh-keygen.
func SSHKeyGenParsePublicKey(key string) (string, int, error) {
	// The ssh-keygen in Windows does not print key type, so no need go further.
	if setting.IsWindows {
		return "", 0, nil
	}

	tmpName, err := writeTmpKeyFile(key)
	if err != nil {
		return "", 0, fmt.Errorf("writeTmpKeyFile: %v", err)
	}
	defer os.Remove(tmpName)

	stdout, stderr, err := process.GetManager().Exec("SSHKeyGenParsePublicKey", setting.SSH.KeygenPath, "-lf", tmpName)
	if err != nil {
		return "", 0, fmt.Errorf("fail to parse public key: %s - %s", err, stderr)
	}
	if strings.Contains(stdout, "is not a public key file") {
		return "", 0, ErrKeyUnableVerify{stdout}
	}

	fields := strings.Split(stdout, " ")
	if len(fields) < 4 {
		return "", 0, fmt.Errorf("invalid public key line: %s", stdout)
	}

	keyType := strings.Trim(fields[len(fields)-1], "()\r\n")
	return strings.ToLower(keyType), com.StrTo(fields[0]).MustInt(), nil
}

// SSHNativeParsePublicKey extracts the key type and length using the golang SSH library.
func SSHNativeParsePublicKey(keyLine string) (string, int, error) {
	fields := strings.Fields(keyLine)
	if len(fields) < 2 {
		return "", 0, fmt.Errorf("not enough fields in public key line: %s", keyLine)
	}

	raw, err := base64.StdEncoding.DecodeString(fields[1])
	if err != nil {
		return "", 0, err
	}

	pkey, err := ssh.ParsePublicKey(raw)
	if err != nil {
		if strings.Contains(err.Error(), "ssh: unknown key algorithm") {
			return "", 0, ErrKeyUnableVerify{err.Error()}
		}
		return "", 0, fmt.Errorf("ParsePublicKey: %v", err)
	}

	// The ssh library can parse the key, so next we find out what key exactly we have.
	switch pkey.Type() {
	case ssh.KeyAlgoDSA:
		rawPub := struct {
			Name       string
			P, Q, G, Y *big.Int
		}{}
		if err := ssh.Unmarshal(pkey.Marshal(), &rawPub); err != nil {
			return "", 0, err
		}
		// as per https://bugzilla.mindrot.org/show_bug.cgi?id=1647 we should never
		// see dsa keys != 1024 bit, but as it seems to work, we will not check here
		return "dsa", rawPub.P.BitLen(), nil // use P as per crypto/dsa/dsa.go (is L)
	case ssh.KeyAlgoRSA:
		rawPub := struct {
			Name string
			E    *big.Int
			N    *big.Int
		}{}
		if err := ssh.Unmarshal(pkey.Marshal(), &rawPub); err != nil {
			return "", 0, err
		}
		return "rsa", rawPub.N.BitLen(), nil // use N as per crypto/rsa/rsa.go (is bits)
	case ssh.KeyAlgoECDSA256:
		return "ecdsa", 256, nil
	case ssh.KeyAlgoECDSA384:
		return "ecdsa", 384, nil
	case ssh.KeyAlgoECDSA521:
		return "ecdsa", 521, nil
	case ssh.KeyAlgoED25519:
		return "ed25519", 256, nil
	}
	return "", 0, fmt.Errorf("unsupported key length detection for type: %s", pkey.Type())
}

// CheckPublicKeyString checks if the given public key string is recognized by SSH.
// It returns the actual public key line on success.
func CheckPublicKeyString(content string) (_ string, err error) {
	if setting.SSH.Disabled {
		return "", ErrSSHDisabled{}
	}

	content, err = parseKeyString(content)
	if err != nil {
		return "", err
	}

	content = strings.TrimRight(content, "\n\r")
	if strings.ContainsAny(content, "\n\r") {
		return "", errors.New("only a single line with a single key please")
	}

	// remove any unnecessary whitespace now
	content = strings.TrimSpace(content)

	if !setting.SSH.MinimumKeySizeCheck {
		return content, nil
	}

	var (
		fnName  string
		keyType string
		length  int
	)
	if setting.SSH.StartBuiltinServer {
		fnName = "SSHNativeParsePublicKey"
		keyType, length, err = SSHNativeParsePublicKey(content)
	} else {
		fnName = "SSHKeyGenParsePublicKey"
		keyType, length, err = SSHKeyGenParsePublicKey(content)
	}
	if err != nil {
		return "", fmt.Errorf("%s: %v", fnName, err)
	}
	log.Trace("Key info [native: %v]: %s-%d", setting.SSH.StartBuiltinServer, keyType, length)

	if minLen, found := setting.SSH.MinimumKeySizes[keyType]; found && length >= minLen {
		return content, nil
	} else if found && length < minLen {
		return "", fmt.Errorf("key length is not enough: got %d, needs %d", length, minLen)
	}
	return "", fmt.Errorf("key type is not allowed: %s", keyType)
}

// appendAuthorizedKeysToFile appends new SSH keys' content to authorized_keys file.
func appendAuthorizedKeysToFile(keys ...*PublicKey) error {
	sshOpLocker.Lock()
	defer sshOpLocker.Unlock()

	fPath := filepath.Join(setting.SSH.RootPath, "authorized_keys")
	f, err := os.OpenFile(fPath, os.O_CREATE|os.O_WRONLY|os.O_APPEND, 0600)
	if err != nil {
		return err
	}
	defer f.Close()

	// Note: chmod command does not support in Windows.
	if !setting.IsWindows {
		fi, err := f.Stat()
		if err != nil {
			return err
		}

		// .ssh directory should have mode 700, and authorized_keys file should have mode 600.
		if fi.Mode().Perm() > 0600 {
			log.Error(4, "authorized_keys file has unusual permission flags: %s - setting to -rw-------", fi.Mode().Perm().String())
			if err = f.Chmod(0600); err != nil {
				return err
			}
		}
	}

	for _, key := range keys {
		if _, err = f.WriteString(key.AuthorizedString()); err != nil {
			return err
		}
	}
	return nil
}

// checkKeyFingerprint only checks if key fingerprint has been used as public key,
// it is OK to use same key as deploy key for multiple repositories/users.
func checkKeyFingerprint(e Engine, fingerprint string) error {
	has, err := e.Get(&PublicKey{
		Fingerprint: fingerprint,
		Type:        KeyTypeUser,
	})
	if err != nil {
		return err
	} else if has {
		return ErrKeyAlreadyExist{0, fingerprint, ""}
	}
	return nil
}

func calcFingerprint(publicKeyContent string) (string, error) {
	// Calculate fingerprint.
	tmpPath, err := writeTmpKeyFile(publicKeyContent)
	if err != nil {
		return "", err
	}
	defer os.Remove(tmpPath)
	stdout, stderr, err := process.GetManager().Exec("AddPublicKey", "ssh-keygen", "-lf", tmpPath)
	if err != nil {
		return "", fmt.Errorf("'ssh-keygen -lf %s' failed with error '%s': %s", tmpPath, err, stderr)
	} else if len(stdout) < 2 {
		return "", errors.New("not enough output for calculating fingerprint: " + stdout)
	}
	return strings.Split(stdout, " ")[1], nil
}

func addKey(e Engine, key *PublicKey) (err error) {
	if len(key.Fingerprint) <= 0 {
		key.Fingerprint, err = calcFingerprint(key.Content)
		if err != nil {
			return err
		}
	}

	// Save SSH key.
	if _, err = e.Insert(key); err != nil {
		return err
	}

	// Don't need to rewrite this file if builtin SSH server is enabled.
	if setting.SSH.StartBuiltinServer {
		return nil
	}
	return appendAuthorizedKeysToFile(key)
}

// AddPublicKey adds new public key to database and authorized_keys file.
func AddPublicKey(ownerID int64, name, content string) (*PublicKey, error) {
	log.Trace(content)

	fingerprint, err := calcFingerprint(content)
	if err != nil {
		return nil, err
	}

	if err := checkKeyFingerprint(x, fingerprint); err != nil {
		return nil, err
	}

	// Key name of same user cannot be duplicated.
	has, err := x.
		Where("owner_id = ? AND name = ?", ownerID, name).
		Get(new(PublicKey))
	if err != nil {
		return nil, err
	} else if has {
		return nil, ErrKeyNameAlreadyUsed{ownerID, name}
	}

	sess := x.NewSession()
	defer sess.Close()
	if err = sess.Begin(); err != nil {
		return nil, err
	}

	key := &PublicKey{
		OwnerID:     ownerID,
		Name:        name,
		Fingerprint: fingerprint,
		Content:     content,
		Mode:        AccessModeWrite,
		Type:        KeyTypeUser,
	}
	if err = addKey(sess, key); err != nil {
		return nil, fmt.Errorf("addKey: %v", err)
	}

	return key, sess.Commit()
}

// GetPublicKeyByID returns public key by given ID.
func GetPublicKeyByID(keyID int64) (*PublicKey, error) {
	key := new(PublicKey)
	has, err := x.
		Id(keyID).
		Get(key)
	if err != nil {
		return nil, err
	} else if !has {
		return nil, ErrKeyNotExist{keyID}
	}
	return key, nil
}

// SearchPublicKeyByContent searches content as prefix (leak e-mail part)
// and returns public key found.
func SearchPublicKeyByContent(content string) (*PublicKey, error) {
	key := new(PublicKey)
	has, err := x.
		Where("content like ?", content+"%").
		Get(key)
	if err != nil {
		return nil, err
	} else if !has {
		return nil, ErrKeyNotExist{}
	}
	return key, nil
}

// ListPublicKeys returns a list of public keys belongs to given user.
func ListPublicKeys(uid int64) ([]*PublicKey, error) {
	keys := make([]*PublicKey, 0, 5)
	return keys, x.
		Where("owner_id = ?", uid).
		Find(&keys)
}

// UpdatePublicKeyUpdated updates public key use time.
func UpdatePublicKeyUpdated(id int64) error {
	// Check if key exists before update as affected rows count is unreliable
	//    and will return 0 affected rows if two updates are made at the same time
	if cnt, err := x.ID(id).Count(&PublicKey{}); err != nil {
		return err
	} else if cnt != 1 {
		return ErrKeyNotExist{id}
	}

	_, err := x.ID(id).Cols("updated_unix").Update(&PublicKey{
		UpdatedUnix: time.Now().Unix(),
	})
	if err != nil {
		return err
	}
	return nil
}

// deletePublicKeys does the actual key deletion but does not update authorized_keys file.
func deletePublicKeys(e *xorm.Session, keyIDs ...int64) error {
	if len(keyIDs) == 0 {
		return nil
	}

	_, err := e.In("id", keyIDs).Delete(new(PublicKey))
	return err
}

// DeletePublicKey deletes SSH key information both in database and authorized_keys file.
func DeletePublicKey(doer *User, id int64) (err error) {
	key, err := GetPublicKeyByID(id)
	if err != nil {
		return err
	}

	// Check if user has access to delete this key.
	if !doer.IsAdmin && doer.ID != key.OwnerID {
		return ErrKeyAccessDenied{doer.ID, key.ID, "public"}
	}

	sess := x.NewSession()
	defer sess.Close()
	if err = sess.Begin(); err != nil {
		return err
	}

	if err = deletePublicKeys(sess, id); err != nil {
		return err
	}

	if err = sess.Commit(); err != nil {
		return err
	}

	return RewriteAllPublicKeys()
}

// RewriteAllPublicKeys removes any authorized key and rewrite all keys from database again.
// Note: x.Iterate does not get latest data after insert/delete, so we have to call this function
// outside any session scope independently.
func RewriteAllPublicKeys() error {
	sshOpLocker.Lock()
	defer sshOpLocker.Unlock()

	fPath := filepath.Join(setting.SSH.RootPath, "authorized_keys")
	tmpPath := fPath + ".tmp"
	t, err := os.OpenFile(tmpPath, os.O_RDWR|os.O_CREATE|os.O_TRUNC, 0600)
	if err != nil {
		return err
	}
	defer func() {
		t.Close()
		os.Remove(tmpPath)
	}()

	if setting.SSH.AuthorizedKeysBackup && com.IsExist(fPath) {
		bakPath := fmt.Sprintf("%s_%d.gitea_bak", fPath, time.Now().Unix())
		if err = com.Copy(fPath, bakPath); err != nil {
			return err
		}
	}

	err = x.Iterate(new(PublicKey), func(idx int, bean interface{}) (err error) {
		_, err = t.WriteString((bean.(*PublicKey)).AuthorizedString())
		return err
	})
	if err != nil {
		return err
	}

	if com.IsExist(fPath) {
		f, err := os.Open(fPath)
		if err != nil {
			return err
		}
		scanner := bufio.NewScanner(f)
		for scanner.Scan() {
			line := scanner.Text()
			if strings.HasPrefix(line, tplCommentPrefix) {
				scanner.Scan()
				continue
			}
			_, err = t.WriteString(line + "\n")
			if err != nil {
				return err
			}
		}
		defer f.Close()
	}

	return os.Rename(tmpPath, fPath)
}

// ________                .__                 ____  __.
// \______ \   ____ ______ |  |   ____ ___.__.|    |/ _|____ ___.__.
//  |    |  \_/ __ \\____ \|  |  /  _ <   |  ||      <_/ __ <   |  |
//  |    `   \  ___/|  |_> >  |_(  <_> )___  ||    |  \  ___/\___  |
// /_______  /\___  >   __/|____/\____// ____||____|__ \___  > ____|
//         \/     \/|__|               \/             \/   \/\/

// DeployKey represents deploy key information and its relation with repository.
type DeployKey struct {
	ID          int64 `xorm:"pk autoincr"`
	KeyID       int64 `xorm:"UNIQUE(s) INDEX"`
	RepoID      int64 `xorm:"UNIQUE(s) INDEX"`
	Name        string
	Fingerprint string
	Content     string `xorm:"-"`

	Created           time.Time `xorm:"-"`
	CreatedUnix       int64     `xorm:"created"`
	Updated           time.Time `xorm:"-"`
	UpdatedUnix       int64     `xorm:"updated"`
	HasRecentActivity bool      `xorm:"-"`
	HasUsed           bool      `xorm:"-"`
}

// AfterLoad is invoked from XORM after setting the values of all fields of this object.
func (key *DeployKey) AfterLoad() {
	key.Created = time.Unix(key.CreatedUnix, 0).Local()
	key.Updated = time.Unix(key.UpdatedUnix, 0).Local()
	key.HasUsed = key.Updated.After(key.Created)
	key.HasRecentActivity = key.Updated.Add(7 * 24 * time.Hour).After(time.Now())
}

// GetContent gets associated public key content.
func (key *DeployKey) GetContent() error {
	pkey, err := GetPublicKeyByID(key.KeyID)
	if err != nil {
		return err
	}
	key.Content = pkey.Content
	return nil
}

func checkDeployKey(e Engine, keyID, repoID int64, name string) error {
	// Note: We want error detail, not just true or false here.
	has, err := e.
		Where("key_id = ? AND repo_id = ?", keyID, repoID).
		Get(new(DeployKey))
	if err != nil {
		return err
	} else if has {
		return ErrDeployKeyAlreadyExist{keyID, repoID}
	}

	has, err = e.
		Where("repo_id = ? AND name = ?", repoID, name).
		Get(new(DeployKey))
	if err != nil {
		return err
	} else if has {
		return ErrDeployKeyNameAlreadyUsed{repoID, name}
	}

	return nil
}

// addDeployKey adds new key-repo relation.
func addDeployKey(e *xorm.Session, keyID, repoID int64, name, fingerprint string) (*DeployKey, error) {
	if err := checkDeployKey(e, keyID, repoID, name); err != nil {
		return nil, err
	}

	key := &DeployKey{
		KeyID:       keyID,
		RepoID:      repoID,
		Name:        name,
		Fingerprint: fingerprint,
	}
	_, err := e.Insert(key)
	return key, err
}

// HasDeployKey returns true if public key is a deploy key of given repository.
func HasDeployKey(keyID, repoID int64) bool {
	has, _ := x.
		Where("key_id = ? AND repo_id = ?", keyID, repoID).
		Get(new(DeployKey))
	return has
}

// AddDeployKey add new deploy key to database and authorized_keys file.
func AddDeployKey(repoID int64, name, content string) (*DeployKey, error) {
	fingerprint, err := calcFingerprint(content)
	if err != nil {
		return nil, err
	}

	pkey := &PublicKey{
		Fingerprint: fingerprint,
		Mode:        AccessModeRead,
		Type:        KeyTypeDeploy,
	}
	has, err := x.Get(pkey)
	if err != nil {
		return nil, err
	}

	sess := x.NewSession()
	defer sess.Close()
	if err = sess.Begin(); err != nil {
		return nil, err
	}

	// First time use this deploy key.
	if !has {
		pkey.Content = content
		pkey.Name = name
		if err = addKey(sess, pkey); err != nil {
			return nil, fmt.Errorf("addKey: %v", err)
		}
	}

	key, err := addDeployKey(sess, pkey.ID, repoID, name, pkey.Fingerprint)
	if err != nil {
		return nil, fmt.Errorf("addDeployKey: %v", err)
	}

	return key, sess.Commit()
}

// GetDeployKeyByID returns deploy key by given ID.
func GetDeployKeyByID(id int64) (*DeployKey, error) {
	key := new(DeployKey)
	has, err := x.ID(id).Get(key)
	if err != nil {
		return nil, err
	} else if !has {
		return nil, ErrDeployKeyNotExist{id, 0, 0}
	}
	return key, nil
}

// GetDeployKeyByRepo returns deploy key by given public key ID and repository ID.
func GetDeployKeyByRepo(keyID, repoID int64) (*DeployKey, error) {
	key := &DeployKey{
		KeyID:  keyID,
		RepoID: repoID,
	}
	has, err := x.Get(key)
	if err != nil {
		return nil, err
	} else if !has {
		return nil, ErrDeployKeyNotExist{0, keyID, repoID}
	}
	return key, nil
}

// UpdateDeployKey updates deploy key information.
func UpdateDeployKey(key *DeployKey) error {
	_, err := x.ID(key.ID).AllCols().Update(key)
	return err
}

// DeleteDeployKey deletes deploy key from its repository authorized_keys file if needed.
func DeleteDeployKey(doer *User, id int64) error {
	key, err := GetDeployKeyByID(id)
	if err != nil {
		if IsErrDeployKeyNotExist(err) {
			return nil
		}
		return fmt.Errorf("GetDeployKeyByID: %v", err)
	}

	// Check if user has access to delete this key.
	if !doer.IsAdmin {
		repo, err := GetRepositoryByID(key.RepoID)
		if err != nil {
			return fmt.Errorf("GetRepositoryByID: %v", err)
		}
		yes, err := HasAccess(doer.ID, repo, AccessModeAdmin)
		if err != nil {
			return fmt.Errorf("HasAccess: %v", err)
		} else if !yes {
			return ErrKeyAccessDenied{doer.ID, key.ID, "deploy"}
		}
	}

	sess := x.NewSession()
	defer sess.Close()
	if err = sess.Begin(); err != nil {
		return err
	}

	if _, err = sess.ID(key.ID).Delete(new(DeployKey)); err != nil {
		return fmt.Errorf("delete deploy key [%d]: %v", key.ID, err)
	}

	// Check if this is the last reference to same key content.
	has, err := sess.
		Where("key_id = ?", key.KeyID).
		Get(new(DeployKey))
	if err != nil {
		return err
	} else if !has {
		if err = deletePublicKeys(sess, key.KeyID); err != nil {
			return err
		}
	}

	return sess.Commit()
}

// ListDeployKeys returns all deploy keys by given repository ID.
func ListDeployKeys(repoID int64) ([]*DeployKey, error) {
	keys := make([]*DeployKey, 0, 5)
	return keys, x.
		Where("repo_id = ?", repoID).
		Find(&keys)
}