jwt: add more helpers (DefaultRSA and DefaultHMAC)

Former-commit-id: fe06c0e0f4d7e121c678ffda7ac702ae865abd00

_examples/miscellaneous/jwt/main.go

@@ -14,19 +14,12 @@ type UserClaims struct {
 }
 
 func main() {
-	// hmac
-	key := []byte("secret")
-	j, err := jwt.New(1*time.Minute, jwt.HS256, key)
-	if err != nil {
-		panic(err)
-	}
-
-	// OPTIONAL encryption:
-	encryptionKey := []byte("itsa16bytesecret")
-	err = j.WithEncryption(jwt.A128GCM, jwt.DIRECT, encryptionKey)
-	if err != nil {
-		panic(err)
-	}
+	// Get keys from system's environment variables
+	// JWT_SECRET (for signing and verification) and JWT_SECRET_ENC(for encryption and decryption),
+	// or defaults to "secret" and "itsa16bytesecret" respectfully.
+	//
+	// Use the `jwt.New` instead for more flexibility, if necessary.
+	j := jwt.DefaultHMAC(15*time.Minute, "secret", "itsa16bytesecret")
 
 	app := iris.New()
 	app.Logger().SetLevel("debug")
@@ -74,12 +67,62 @@ func main() {
 }
 
 /*
-func load_From_File_Example() {
+func default_RSA_Example() {
+	j := jwt.DefaultRSA(1 * time.Minute)
+}
+
+Same as:
+
+func load_File_Or_Generate_RSA_Example() {
+	signKey, err := jwt.LoadRSA("jwt_sign.key", 2048)
+	if err != nil {
+		panic(err)
+	}
+
+	j, err := jwt.New(15*time.Minute, jwt.RS256, signKey)
+	if err != nil {
+		panic(err)
+	}
+
+	encKey, err := jwt.LoadRSA("jwt_enc.key", 2048)
+	if err != nil {
+		panic(err)
+	}
+	err = j.WithEncryption(jwt.A128CBCHS256, jwt.RSA15, encKey)
+	if err != nil {
+		panic(err)
+	}
+}
+*/
+
+/*
+func hmac_Example() {
+	// hmac
+	key := []byte("secret")
+	j, err := jwt.New(15*time.Minute, jwt.HS256, key)
+	if err != nil {
+		panic(err)
+	}
+
+	// OPTIONAL encryption:
+	encryptionKey := []byte("itsa16bytesecret")
+	err = j.WithEncryption(jwt.A128GCM, jwt.DIRECT, encryptionKey)
+	if err != nil {
+		panic(err)
+	}
+}
+*/
+
+/*
+func load_From_File_With_Password_Example() {
 	b, err := ioutil.ReadFile("./private_rsa.pem")
 	if err != nil {
 		panic(err)
 	}
-	signKey := jwt.MustParseRSAPrivateKey(b, []byte("pass"))
+	signKey,err := jwt.ParseRSAPrivateKey(b, []byte("pass"))
+	if err != nil {
+		panic(err)
+	}
 
 	j, err := jwt.New(15*time.Minute, jwt.RS256, signKey)
 	if err != nil {
@@ -89,23 +132,18 @@ func load_From_File_Example() {
 */
 
 /*
-func random_RSA_Sign_And_Encrypt_Example() {
-	j := jwt.Random(1 * time.Minute)
-}
-*/
-
-/*
-func random_manually_generate_RSA_Example() {
-	signey, err := rsa.GenerateKey(rand.Reader, 2048)
-	if err != nil {
-		panic(err)
-	}
-	encryptionKey, err := rsa.GenerateKey(rand.Reader, 2048)
+func generate_RSA_Example() {
+	signKey, err := rsa.GenerateKey(rand.Reader, 4096)
 	if err != nil {
 		panic(err)
 	}
 
-	j, err := jwt.New(1*time.Minute, jwt.RS256, signey)
+	encryptionKey, err := rsa.GenerateKey(rand.Reader, 4096)
+	if err != nil {
+		panic(err)
+	}
+
+	j, err := jwt.New(15*time.Minute, jwt.RS512, signKey)
 	if err != nil {
 		panic(err)
 	}

context/context.go

@@ -1946,7 +1946,7 @@ func (ctx *context) GetDomain() string {
 	if host, _, err := net.SplitHostPort(hostport); err == nil {
 		// has port.
 		switch host {
-		case "127.0.0.1", "0.0.0.0", "::1", "[::1]", "0:0:0:0:0:0:0", "0:0:0:0:0:0:1":
+		case "127.0.0.1", "0.0.0.0", "::1", "[::1]", "0:0:0:0:0:0:0:0", "0:0:0:0:0:0:0:1":
 			// loopback.
 			return "localhost"
 		default:

middleware/jwt/jwt.go

@@ -2,10 +2,9 @@ package jwt
 
 import (
 	"crypto"
-	"crypto/rand"
-	"crypto/rsa"
 	"encoding/json"
 	"errors"
+	"os"
 	"strings"
 	"time"
 
@@ -112,35 +111,6 @@ type JWT struct {
 	DecriptionKey interface{}
 }
 
-// Random returns a new `JWT` instance
-// with in-memory generated rsa256 signing and encryption keys (development).
-// It panics on errors. Next server ran will invalidate all request tokens.
-//
-// Use the `New` package-level function for production use.
-func Random(maxAge time.Duration) *JWT {
-	sigKey, err := rsa.GenerateKey(rand.Reader, 2048)
-	if err != nil {
-		panic(err)
-	}
-
-	j, err := New(maxAge, RS256, sigKey)
-	if err != nil {
-		panic(err)
-	}
-
-	encKey, err := rsa.GenerateKey(rand.Reader, 2048)
-	if err != nil {
-		panic(err)
-	}
-
-	err = j.WithEncryption(A128CBCHS256, RSA15, encKey)
-	if err != nil {
-		panic(err)
-	}
-
-	return j
-}
-
 type privateKey interface{ Public() crypto.PublicKey }
 
 // New returns a new JWT instance.
@@ -157,7 +127,7 @@ type privateKey interface{ Public() crypto.PublicKey }
 // 1. Generate key file, e.g:
 // 		$ openssl genrsa -des3 -out private.pem 2048
 // 2. Read file contents with io.ReadFile("./private.pem")
-// 3. Pass the []byte result to the `MustParseRSAPrivateKey(contents, password)` package-level helper
+// 3. Pass the []byte result to the `ParseRSAPrivateKey(contents, password)` package-level helper
 // 4. Use the result *rsa.PrivateKey as "key" input parameter of this `New` function.
 //
 // See aliases.go file for available algorithms.
@@ -185,6 +155,99 @@ func New(maxAge time.Duration, alg SignatureAlgorithm, key interface{}) (*JWT, e
 	return j, nil
 }
 
+// RSA filenames for `DefaultRSA`.
+const (
+	SignFilename = "jwt_sign.key"
+	EncFilename  = "jwt_enc.key"
+)
+
+// DefaultRSA returns a new `JWT` instance.
+// It tries to parse RSA256 keys from "jwt_sign.key" and (optionally) "jwt_enc.key" files
+// in the current working directory, and if not found, it generates and exports the keys.
+//
+// It panics on errors.
+// Use the `New` package-level function instead for more options.
+func DefaultRSA(maxAge time.Duration) *JWT {
+	// Do not try to create or load enc key if only sign key already exists.
+	withEncryption := true
+	if fileExists(SignFilename) {
+		withEncryption = fileExists(EncFilename)
+	}
+
+	sigKey, err := LoadRSA(SignFilename, 2048)
+	if err != nil {
+		panic(err)
+	}
+
+	j, err := New(maxAge, RS256, sigKey)
+	if err != nil {
+		panic(err)
+	}
+
+	if withEncryption {
+		encKey, err := LoadRSA(EncFilename, 2048)
+		if err != nil {
+			panic(err)
+		}
+		err = j.WithEncryption(A128CBCHS256, RSA15, encKey)
+		if err != nil {
+			panic(err)
+		}
+	}
+
+	return j
+}
+
+const (
+	signEnv = "JWT_SECRET"
+	encEnv  = "JWT_SECRET_ENC"
+)
+
+func getenv(key string, def string) string {
+	v := os.Getenv(key)
+	if v == "" {
+		return def
+	}
+
+	return v
+}
+
+// DefaultHMAC returns a new `JWT` instance.
+// It tries to read hmac256 secret keys from system environment variables:
+// * JWT_SECRET for signing and verification key and
+// * JWT_SECRET_ENC for encryption and decryption key
+// and defaults them to the given "keys" respectfully.
+//
+// It panics on errors.
+// Use the `New` package-level function instead for more options.
+func DefaultHMAC(maxAge time.Duration, keys ...string) *JWT {
+	var defaultSignSecret, defaultEncSecret string
+
+	switch len(keys) {
+	case 1:
+		defaultSignSecret = keys[0]
+	case 2:
+		defaultEncSecret = keys[1]
+	}
+
+	signSecret := getenv(signEnv, defaultSignSecret)
+	encSecret := getenv(encEnv, defaultEncSecret)
+
+	j, err := New(maxAge, HS256, []byte(signSecret))
+	if err != nil {
+		panic(err)
+	}
+
+	if encSecret != "" {
+		err = j.WithEncryption(A128GCM, DIRECT, []byte(encSecret))
+		if err != nil {
+			panic(err)
+		}
+	}
+
+	return j
+}
+
 // WithEncryption method enables encryption and decryption of the token.
 // It sets an appropriate encrypter(`Encrypter` and the `DecriptionKey` fields) based on the key type.
 func (j *JWT) WithEncryption(contentEncryption ContentEncryption, alg KeyAlgorithm, key interface{}) error {

middleware/jwt/jwt_test.go

@@ -2,6 +2,7 @@
 package jwt_test
 
 import (
+	"os"
 	"testing"
 	"time"
 
@@ -18,12 +19,21 @@ type userClaims struct {
 const testMaxAge = 3 * time.Second
 
 // Random RSA verification and encryption.
-func TestRSA(t *testing.T) {
-	j := jwt.Random(testMaxAge)
+func TestDefaultRSA(t *testing.T) {
+	j := jwt.DefaultRSA(testMaxAge)
+	t.Cleanup(func() {
+		os.Remove(jwt.SignFilename)
+		os.Remove(jwt.EncFilename)
+	})
 	testWriteVerifyToken(t, j)
 }
 
 // HMAC verification and encryption.
+func TestDefaultHMAC(t *testing.T) {
+	j := jwt.DefaultHMAC(testMaxAge, "secret", "itsa16bytesecret")
+	testWriteVerifyToken(t, j)
+}
+
 func TestHMAC(t *testing.T) {
 	j, err := jwt.New(testMaxAge, jwt.HS256, []byte("secret"))
 	if err != nil {

middleware/jwt/rsa_util.go

@@ -0,0 +1,106 @@
+package jwt
+
+import (
+	"crypto/rand"
+	"crypto/rsa"
+	"crypto/x509"
+	"encoding/pem"
+	"errors"
+	"io/ioutil"
+	"os"
+)
+
+// LoadRSA tries to read RSA Private Key from "fname" system file,
+// if does not exist then it generates a new random one based on "bits" (e.g. 2048, 4096)
+// and exports it to a new "fname" file.
+func LoadRSA(fname string, bits int) (key *rsa.PrivateKey, err error) {
+	exists := fileExists(fname)
+	if exists {
+		key, err = importFromFile(fname)
+	} else {
+		key, err = rsa.GenerateKey(rand.Reader, bits)
+	}
+
+	if err != nil {
+		return
+	}
+
+	if !exists {
+		err = exportToFile(key, fname)
+	}
+
+	return
+}
+
+func exportToFile(key *rsa.PrivateKey, filename string) error {
+	b := x509.MarshalPKCS1PrivateKey(key)
+	encoded := pem.EncodeToMemory(
+		&pem.Block{
+			Type:  "RSA PRIVATE KEY",
+			Bytes: b,
+		},
+	)
+
+	return ioutil.WriteFile(filename, encoded, 0644)
+}
+
+func importFromFile(filename string) (*rsa.PrivateKey, error) {
+	b, err := ioutil.ReadFile(filename)
+	if err != nil {
+		return nil, err
+	}
+
+	return ParseRSAPrivateKey(b, nil)
+}
+
+func fileExists(filename string) bool {
+	info, err := os.Stat(filename)
+	if os.IsNotExist(err) {
+		return false
+	}
+	return !info.IsDir()
+}
+
+var (
+	// ErrNotPEM is an error type of the `ParseXXX` function(s) fired
+	// when the data are not PEM-encoded.
+	ErrNotPEM = errors.New("key must be PEM encoded")
+	// ErrInvalidKey is an error type of the `ParseXXX` function(s) fired
+	// when the contents are not type of rsa private key.
+	ErrInvalidKey = errors.New("key is not of type *rsa.PrivateKey")
+)
+
+// ParseRSAPrivateKey encodes a PEM-encoded PKCS1 or PKCS8 private key protected with a password.
+func ParseRSAPrivateKey(key, password []byte) (*rsa.PrivateKey, error) {
+	block, _ := pem.Decode(key)
+	if block == nil {
+		return nil, ErrNotPEM
+	}
+
+	var (
+		parsedKey interface{}
+		err       error
+	)
+
+	var blockDecrypted []byte
+	if len(password) > 0 {
+		if blockDecrypted, err = x509.DecryptPEMBlock(block, password); err != nil {
+			return nil, err
+		}
+	} else {
+		blockDecrypted = block.Bytes
+	}
+
+	if parsedKey, err = x509.ParsePKCS1PrivateKey(blockDecrypted); err != nil {
+		if parsedKey, err = x509.ParsePKCS8PrivateKey(blockDecrypted); err != nil {
+			return nil, err
+		}
+	}
+
+	privateKey, ok := parsedKey.(*rsa.PrivateKey)
+	if !ok {
+		return nil, ErrInvalidKey
+	}
+
+	return privateKey, nil
+}

middleware/jwt/util.go

@@ -1,98 +0,0 @@
-package jwt
-
-import (
-	"crypto/rsa"
-	"crypto/x509"
-	"encoding/pem"
-	"errors"
-)
-
-// ErrNotPEM is a panic error of the MustParseXXX functions when the data are not PEM-encoded.
-var ErrNotPEM = errors.New("key must be PEM encoded")
-
-// MustParseRSAPrivateKey encodes a PEM-encoded PKCS1 or PKCS8 private key protected with a password.
-func MustParseRSAPrivateKey(key, password []byte) *rsa.PrivateKey {
-	block, _ := pem.Decode(key)
-	if block == nil {
-		panic(ErrNotPEM)
-	}
-
-	var (
-		parsedKey interface{}
-		err       error
-	)
-
-	var blockDecrypted []byte
-	if blockDecrypted, err = x509.DecryptPEMBlock(block, password); err != nil {
-		panic(err)
-	}
-
-	if parsedKey, err = x509.ParsePKCS1PrivateKey(blockDecrypted); err != nil {
-		if parsedKey, err = x509.ParsePKCS8PrivateKey(blockDecrypted); err != nil {
-			panic(err)
-		}
-	}
-
-	privateKey, ok := parsedKey.(*rsa.PrivateKey)
-	if !ok {
-		panic("key is not of type *rsa.PrivateKey")
-	}
-
-	return privateKey
-}
-
-// MustParseRSAPublicKey encodes a PEM encoded PKCS1 or PKCS8 public key.
-func MustParseRSAPublicKey(key []byte) *rsa.PublicKey {
-	var err error
-
-	// Parse PEM block
-	var block *pem.Block
-	if block, _ = pem.Decode(key); block == nil {
-		panic(ErrNotPEM)
-	}
-
-	// Parse the key
-	var parsedKey interface{}
-	if parsedKey, err = x509.ParsePKIXPublicKey(block.Bytes); err != nil {
-		if cert, err := x509.ParseCertificate(block.Bytes); err == nil {
-			parsedKey = cert.PublicKey
-		} else {
-			panic(err)
-		}
-	}
-
-	var pkey *rsa.PublicKey
-	var ok bool
-	if pkey, ok = parsedKey.(*rsa.PublicKey); !ok {
-		panic("key is not of type *rsa.PublicKey")
-	}
-
-	return pkey
-}
-
-/*
-// MustParseEd25519 PEM encoded Ed25519.
-func MustParseEd25519(key []byte) ed25519.PrivateKey {
-	// Parse PEM block
-	block, _ := pem.Decode(key)
-	if block == nil {
-		panic(ErrNotPEM)
-	}
-
-	type ed25519PrivKey struct {
-		Version          int
-		ObjectIdentifier struct {
-			ObjectIdentifier asn1.ObjectIdentifier
-		}
-		PrivateKey []byte
-	}
-
-	var asn1PrivKey ed25519PrivKey
-	if _, err := asn1.Unmarshal(block.Bytes, &asn1PrivKey); err != nil {
-		panic(err)
-	}
-
-	privateKey := ed25519.NewKeyFromSeed(asn1PrivKey.PrivateKey[2:])
-	return privateKey
-}
-*/