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
|
package storage
import (
"context"
"crypto/rand"
"encoding/hex"
"fmt"
"time"
)
const (
ChallengeLength = 32 // bytes
ChallengeTTL = 2 * time.Minute
)
func generateChallenge() (string, error) {
bytes := make([]byte, ChallengeLength)
if _, err := rand.Read(bytes); err != nil {
return "", fmt.Errorf("failed to generate challenge: %w", err)
}
return hex.EncodeToString(bytes), nil
}
func (s *Storage) CreateAuthChallenge(ctx context.Context) (string, error) {
challenge, err := generateChallenge()
if err != nil {
return "", err
}
now := time.Now().Unix()
expiresAt := time.Now().Add(ChallengeTTL).Unix()
_, err = s.db.ExecContext(ctx,
"INSERT INTO auth_challenges (challenge, created_at, expires_at, used) VALUES (?, ?, ?, 0)",
challenge, now, expiresAt,
)
if err != nil {
return "", fmt.Errorf("failed to store challenge: %w", err)
}
return challenge, nil
}
func (s *Storage) ValidateAndConsumeChallenge(ctx context.Context, challenge string) error {
tx, err := s.db.BeginTx(ctx, nil)
if err != nil {
return fmt.Errorf("failed to begin transaction: %w", err)
}
defer tx.Rollback()
var expiresAt int64
var used int
err = tx.QueryRowContext(ctx,
"SELECT expires_at, used FROM auth_challenges WHERE challenge = ?",
challenge,
).Scan(&expiresAt, &used)
if err != nil {
return fmt.Errorf("challenge not found or invalid")
}
if used != 0 {
return fmt.Errorf("challenge already used")
}
if time.Now().Unix() > expiresAt {
return fmt.Errorf("challenge expired")
}
_, err = tx.ExecContext(ctx,
"UPDATE auth_challenges SET used = 1 WHERE challenge = ?",
challenge,
)
if err != nil {
return fmt.Errorf("failed to mark challenge as used: %w", err)
}
return tx.Commit()
}
func (s *Storage) CleanupExpiredChallenges(ctx context.Context) error {
now := time.Now().Unix()
_, err := s.db.ExecContext(ctx,
"DELETE FROM auth_challenges WHERE expires_at < ?",
now,
)
return err
}
|
