Files
eng-pad-server/internal/auth/tokens.go
Kyle Isom 286b886c06 Implement Phase 2: password auth (Argon2id + bearer tokens)
- Argon2id password hashing and verification with configurable params
- Bearer token generation (32-byte random), SHA-256 hashed storage,
  TTL-based expiry
- User creation and authentication helpers
- auth_tokens table added to migrations
- 6 tests: hash/verify, wrong password, create/auth user, token
  create/validate, token expiry

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
2026-03-24 19:49:07 -07:00

68 lines
1.7 KiB
Go

package auth
import (
"crypto/rand"
"crypto/sha256"
"database/sql"
"encoding/hex"
"fmt"
"time"
)
const tokenBytes = 32
// CreateToken generates a bearer token and stores its hash.
func CreateToken(database *sql.DB, userID int64, ttl time.Duration) (string, error) {
raw := make([]byte, tokenBytes)
if _, err := rand.Read(raw); err != nil {
return "", fmt.Errorf("generate token: %w", err)
}
token := hex.EncodeToString(raw)
hash := hashToken(token)
expiresAt := time.Now().Add(ttl).UnixMilli()
_, err := database.Exec(
"INSERT INTO auth_tokens (token_hash, user_id, expires_at, created_at) VALUES (?, ?, ?, ?)",
hash, userID, expiresAt, time.Now().UnixMilli(),
)
if err != nil {
return "", fmt.Errorf("store token: %w", err)
}
return token, nil
}
// ValidateToken checks a bearer token and returns the user ID.
func ValidateToken(database *sql.DB, token string) (int64, error) {
hash := hashToken(token)
var userID int64
var expiresAt int64
err := database.QueryRow(
"SELECT user_id, expires_at FROM auth_tokens WHERE token_hash = ?", hash,
).Scan(&userID, &expiresAt)
if err != nil {
return 0, fmt.Errorf("token not found")
}
if time.Now().UnixMilli() > expiresAt {
// Clean up expired token
_, _ = database.Exec("DELETE FROM auth_tokens WHERE token_hash = ?", hash)
return 0, fmt.Errorf("token expired")
}
return userID, nil
}
// DeleteToken revokes a bearer token.
func DeleteToken(database *sql.DB, token string) error {
hash := hashToken(token)
_, err := database.Exec("DELETE FROM auth_tokens WHERE token_hash = ?", hash)
return err
}
func hashToken(token string) string {
h := sha256.Sum256([]byte(token))
return hex.EncodeToString(h[:])
}