Files
nexus/internal/auth/jwt.go
2026-07-14 05:53:25 -05:00

127 lines
3.5 KiB
Go

package auth
import (
"crypto/rand"
"crypto/sha256"
"encoding/hex"
"fmt"
"time"
"git.arcline.it/ArclineIT/nexus/internal/config"
"github.com/golang-jwt/jwt/v5"
"github.com/google/uuid"
)
// Claims represents the custom JWT claims for Nexus.
type Claims struct {
jwt.RegisteredClaims
Email string `json:"email"`
TokenType string `json:"token_type"` // "access" or "refresh"
}
// TokenPair holds both access and refresh tokens.
type TokenPair struct {
AccessToken string `json:"access_token"`
RefreshToken string `json:"refresh_token"`
ExpiresIn int64 `json:"expires_in"` // seconds until access token expires
TokenType string `json:"token_type"` // always "Bearer"
}
// GenerateTokenPair creates a new access + refresh token pair for a user.
func GenerateTokenPair(cfg *config.Config, userID uuid.UUID, email string) (*TokenPair, error) {
now := time.Now()
accessClaims := Claims{
RegisteredClaims: jwt.RegisteredClaims{
Issuer: cfg.Auth.Issuer,
Subject: userID.String(),
Audience: jwt.ClaimStrings{cfg.Auth.Audience},
ExpiresAt: jwt.NewNumericDate(now.Add(cfg.Auth.AccessTokenDuration)),
IssuedAt: jwt.NewNumericDate(now),
NotBefore: jwt.NewNumericDate(now),
ID: uuid.New().String(),
},
Email: email,
TokenType: "access",
}
accessToken, err := signToken(cfg, accessClaims)
if err != nil {
return nil, fmt.Errorf("signing access token: %w", err)
}
refreshClaims := Claims{
RegisteredClaims: jwt.RegisteredClaims{
Issuer: cfg.Auth.Issuer,
Subject: userID.String(),
Audience: jwt.ClaimStrings{cfg.Auth.Audience},
ExpiresAt: jwt.NewNumericDate(now.Add(cfg.Auth.RefreshTokenDuration)),
IssuedAt: jwt.NewNumericDate(now),
NotBefore: jwt.NewNumericDate(now),
ID: uuid.New().String(),
},
Email: email,
TokenType: "refresh",
}
refreshToken, err := signToken(cfg, refreshClaims)
if err != nil {
return nil, fmt.Errorf("signing refresh token: %w", err)
}
return &TokenPair{
AccessToken: accessToken,
RefreshToken: refreshToken,
ExpiresIn: int64(cfg.Auth.AccessTokenDuration.Seconds()),
TokenType: "Bearer",
}, nil
}
// ValidateToken parses and validates a JWT token string.
func ValidateToken(cfg *config.Config, tokenString string) (*Claims, error) {
token, err := jwt.ParseWithClaims(
tokenString,
&Claims{},
func(t *jwt.Token) (interface{}, error) {
if _, ok := t.Method.(*jwt.SigningMethodHMAC); !ok {
return nil, fmt.Errorf("unexpected signing method: %v", t.Header["alg"])
}
return []byte(cfg.Auth.JWTSecret), nil
},
)
if err != nil {
return nil, fmt.Errorf("parsing token: %w", err)
}
claims, ok := token.Claims.(*Claims)
if !ok || !token.Valid {
return nil, fmt.Errorf("invalid token")
}
return claims, nil
}
// HashToken returns the SHA-256 hash of a token string (for storage).
func HashToken(token string) string {
hash := sha256.Sum256([]byte(token))
return hex.EncodeToString(hash[:])
}
// GenerateSecureToken creates a cryptographically random token.
func GenerateSecureToken(length int) (string, error) {
bytes := make([]byte, length)
if _, err := rand.Read(bytes); err != nil {
return "", fmt.Errorf("generating random bytes: %w", err)
}
return hex.EncodeToString(bytes), nil
}
func signToken(cfg *config.Config, claims Claims) (string, error) {
token := jwt.NewWithClaims(jwt.SigningMethodHS256, claims)
signed, err := token.SignedString([]byte(cfg.Auth.JWTSecret))
if err != nil {
return "", fmt.Errorf("signing token: %w", err)
}
return signed, nil
}