Pattern matching on subject

Co-authored-by: Micah Parks <66095735+MicahParks@users.noreply.github.com>

MIGRATION_GUIDE.md

@@ -2,18 +2,18 @@
 
 Starting from [v4.0.0](https://github.com/golang-jwt/jwt/releases/tag/v4.0.0), the import path will be:
 
-    "github.com/golang-jwt/jwt/v4"
+    "github.com/golang-jwt/jwt/v5"
 
 The `/v4` version will be backwards compatible with existing `v3.x.y` tags in this repo, as well as 
 `github.com/dgrijalva/jwt-go`. For most users this should be a drop-in replacement, if you're having 
 troubles migrating, please open an issue.
 
-You can replace all occurrences of `github.com/dgrijalva/jwt-go` or `github.com/golang-jwt/jwt` with `github.com/golang-jwt/jwt/v4`, either manually or by using tools such as `sed` or `gofmt`.
+You can replace all occurrences of `github.com/dgrijalva/jwt-go` or `github.com/golang-jwt/jwt` with `github.com/golang-jwt/jwt/v5`, either manually or by using tools such as `sed` or `gofmt`.
 
 And then you'd typically run:
 
 ```
-go get github.com/golang-jwt/jwt/v4
+go get github.com/golang-jwt/jwt/v5
 go mod tidy
 ```
 

README.md

@@ -1,12 +1,12 @@
 # jwt-go
 
 [![build](https://github.com/golang-jwt/jwt/actions/workflows/build.yml/badge.svg)](https://github.com/golang-jwt/jwt/actions/workflows/build.yml)
-[![Go Reference](https://pkg.go.dev/badge/github.com/golang-jwt/jwt/v4.svg)](https://pkg.go.dev/github.com/golang-jwt/jwt/v4)
+[![Go Reference](https://pkg.go.dev/badge/github.com/golang-jwt/jwt/v5.svg)](https://pkg.go.dev/github.com/golang-jwt/jwt/v5)
 
 A [go](http://www.golang.org) (or 'golang' for search engine friendliness) implementation of [JSON Web Tokens](https://datatracker.ietf.org/doc/html/rfc7519).
 
 Starting with [v4.0.0](https://github.com/golang-jwt/jwt/releases/tag/v4.0.0) this project adds Go module support, but maintains backwards compatibility with older `v3.x.y` tags and upstream `github.com/dgrijalva/jwt-go`.
-See the [`MIGRATION_GUIDE.md`](./MIGRATION_GUIDE.md) for more information.
+See the [`MIGRATION_GUIDE.md`](./MIGRATION_GUIDE.md) for more information. Version v5.0.0 introduces major improvements to the validation of tokens, but is not entirely backwards compatible. 
 
 > After the original author of the library suggested migrating the maintenance of `jwt-go`, a dedicated team of open source maintainers decided to clone the existing library into this repository. See [dgrijalva/jwt-go#462](https://github.com/dgrijalva/jwt-go/issues/462) for a detailed discussion on this topic.
 
@@ -41,22 +41,22 @@ This library supports the parsing and verification as well as the generation and
 1. To install the jwt package, you first need to have [Go](https://go.dev/doc/install) installed, then you can use the command below to add `jwt-go` as a dependency in your Go program.
 
 ```sh
-go get -u github.com/golang-jwt/jwt/v4
+go get -u github.com/golang-jwt/jwt/v5
 ```
 
 2. Import it in your code:
 
 ```go
-import "github.com/golang-jwt/jwt/v4"
+import "github.com/golang-jwt/jwt/v5"
 ```
 
 ## Examples
 
-See [the project documentation](https://pkg.go.dev/github.com/golang-jwt/jwt/v4) for examples of usage:
+See [the project documentation](https://pkg.go.dev/github.com/golang-jwt/jwt/v5) for examples of usage:
 
-* [Simple example of parsing and validating a token](https://pkg.go.dev/github.com/golang-jwt/jwt/v4#example-Parse-Hmac)
-* [Simple example of building and signing a token](https://pkg.go.dev/github.com/golang-jwt/jwt/v4#example-New-Hmac)
-* [Directory of Examples](https://pkg.go.dev/github.com/golang-jwt/jwt/v4#pkg-examples)
+* [Simple example of parsing and validating a token](https://pkg.go.dev/github.com/golang-jwt/jwt/v5#example-Parse-Hmac)
+* [Simple example of building and signing a token](https://pkg.go.dev/github.com/golang-jwt/jwt/v5#example-New-Hmac)
+* [Directory of Examples](https://pkg.go.dev/github.com/golang-jwt/jwt/v5#pkg-examples)
 
 ## Extensions
 
@@ -110,10 +110,10 @@ Asymmetric signing methods, such as RSA, use different keys for signing and veri
 
 Each signing method expects a different object type for its signing keys. See the package documentation for details. Here are the most common ones:
 
-* The [HMAC signing method](https://pkg.go.dev/github.com/golang-jwt/jwt/v4#SigningMethodHMAC) (`HS256`,`HS384`,`HS512`) expect `[]byte` values for signing and validation
-* The [RSA signing method](https://pkg.go.dev/github.com/golang-jwt/jwt/v4#SigningMethodRSA) (`RS256`,`RS384`,`RS512`) expect `*rsa.PrivateKey` for signing and `*rsa.PublicKey` for validation
-* The [ECDSA signing method](https://pkg.go.dev/github.com/golang-jwt/jwt/v4#SigningMethodECDSA) (`ES256`,`ES384`,`ES512`) expect `*ecdsa.PrivateKey` for signing and `*ecdsa.PublicKey` for validation
-* The [EdDSA signing method](https://pkg.go.dev/github.com/golang-jwt/jwt/v4#SigningMethodEd25519) (`Ed25519`) expect `ed25519.PrivateKey` for signing and `ed25519.PublicKey` for validation
+* The [HMAC signing method](https://pkg.go.dev/github.com/golang-jwt/jwt/v5#SigningMethodHMAC) (`HS256`,`HS384`,`HS512`) expect `[]byte` values for signing and validation
+* The [RSA signing method](https://pkg.go.dev/github.com/golang-jwt/jwt/v5#SigningMethodRSA) (`RS256`,`RS384`,`RS512`) expect `*rsa.PrivateKey` for signing and `*rsa.PublicKey` for validation
+* The [ECDSA signing method](https://pkg.go.dev/github.com/golang-jwt/jwt/v5#SigningMethodECDSA) (`ES256`,`ES384`,`ES512`) expect `*ecdsa.PrivateKey` for signing and `*ecdsa.PublicKey` for validation
+* The [EdDSA signing method](https://pkg.go.dev/github.com/golang-jwt/jwt/v5#SigningMethodEd25519) (`Ed25519`) expect `ed25519.PrivateKey` for signing and `ed25519.PublicKey` for validation
 
 ### JWT and OAuth
 
@@ -131,7 +131,7 @@ This library uses descriptive error messages whenever possible. If you are not g
 
 ## More
 
-Documentation can be found [on pkg.go.dev](https://pkg.go.dev/github.com/golang-jwt/jwt/v4).
+Documentation can be found [on pkg.go.dev](https://pkg.go.dev/github.com/golang-jwt/jwt/v5).
 
 The command line utility included in this project (cmd/jwt) provides a straightforward example of token creation and parsing as well as a useful tool for debugging your own integration. You'll also find several implementation examples in the documentation.
 

claims.go

@@ -1,273 +1,16 @@
 package jwt
 
-import (
-	"crypto/subtle"
-	"fmt"
-	"time"
-)
-
-// Claims must just have a Valid method that determines
-// if the token is invalid for any supported reason
+// Claims represent any form of a JWT Claims Set according to
+// https://datatracker.ietf.org/doc/html/rfc7519#section-4. In order to have a
+// common basis for validation, it is required that an implementation is able to
+// supply at least the claim names provided in
+// https://datatracker.ietf.org/doc/html/rfc7519#section-4.1 namely `exp`,
+// `iat`, `nbf`, `iss` and `aud`.
 type Claims interface {
-	Valid() error
-}
-
-// RegisteredClaims are a structured version of the JWT Claims Set,
-// restricted to Registered Claim Names, as referenced at
-// https://datatracker.ietf.org/doc/html/rfc7519#section-4.1
-//
-// This type can be used on its own, but then additional private and
-// public claims embedded in the JWT will not be parsed. The typical usecase
-// therefore is to embedded this in a user-defined claim type.
-//
-// See examples for how to use this with your own claim types.
-type RegisteredClaims struct {
-	// the `iss` (Issuer) claim. See https://datatracker.ietf.org/doc/html/rfc7519#section-4.1.1
-	Issuer string `json:"iss,omitempty"`
-
-	// the `sub` (Subject) claim. See https://datatracker.ietf.org/doc/html/rfc7519#section-4.1.2
-	Subject string `json:"sub,omitempty"`
-
-	// the `aud` (Audience) claim. See https://datatracker.ietf.org/doc/html/rfc7519#section-4.1.3
-	Audience ClaimStrings `json:"aud,omitempty"`
-
-	// the `exp` (Expiration Time) claim. See https://datatracker.ietf.org/doc/html/rfc7519#section-4.1.4
-	ExpiresAt *NumericDate `json:"exp,omitempty"`
-
-	// the `nbf` (Not Before) claim. See https://datatracker.ietf.org/doc/html/rfc7519#section-4.1.5
-	NotBefore *NumericDate `json:"nbf,omitempty"`
-
-	// the `iat` (Issued At) claim. See https://datatracker.ietf.org/doc/html/rfc7519#section-4.1.6
-	IssuedAt *NumericDate `json:"iat,omitempty"`
-
-	// the `jti` (JWT ID) claim. See https://datatracker.ietf.org/doc/html/rfc7519#section-4.1.7
-	ID string `json:"jti,omitempty"`
-}
-
-// Valid validates time based claims "exp, iat, nbf".
-// There is no accounting for clock skew.
-// As well, if any of the above claims are not in the token, it will still
-// be considered a valid claim.
-func (c RegisteredClaims) Valid() error {
-	vErr := new(ValidationError)
-	now := TimeFunc()
-
-	// The claims below are optional, by default, so if they are set to the
-	// default value in Go, let's not fail the verification for them.
-	if !c.VerifyExpiresAt(now, false) {
-		delta := now.Sub(c.ExpiresAt.Time)
-		vErr.Inner = fmt.Errorf("%s by %s", ErrTokenExpired, delta)
-		vErr.Errors |= ValidationErrorExpired
-	}
-
-	if !c.VerifyIssuedAt(now, false) {
-		vErr.Inner = ErrTokenUsedBeforeIssued
-		vErr.Errors |= ValidationErrorIssuedAt
-	}
-
-	if !c.VerifyNotBefore(now, false) {
-		vErr.Inner = ErrTokenNotValidYet
-		vErr.Errors |= ValidationErrorNotValidYet
-	}
-
-	if vErr.valid() {
-		return nil
-	}
-
-	return vErr
-}
-
-// VerifyAudience compares the aud claim against cmp.
-// If required is false, this method will return true if the value matches or is unset
-func (c *RegisteredClaims) VerifyAudience(cmp string, req bool) bool {
-	return verifyAud(c.Audience, cmp, req)
-}
-
-// VerifyExpiresAt compares the exp claim against cmp (cmp < exp).
-// If req is false, it will return true, if exp is unset.
-func (c *RegisteredClaims) VerifyExpiresAt(cmp time.Time, req bool) bool {
-	if c.ExpiresAt == nil {
-		return verifyExp(nil, cmp, req)
-	}
-
-	return verifyExp(&c.ExpiresAt.Time, cmp, req)
-}
-
-// VerifyIssuedAt compares the iat claim against cmp (cmp >= iat).
-// If req is false, it will return true, if iat is unset.
-func (c *RegisteredClaims) VerifyIssuedAt(cmp time.Time, req bool) bool {
-	if c.IssuedAt == nil {
-		return verifyIat(nil, cmp, req)
-	}
-
-	return verifyIat(&c.IssuedAt.Time, cmp, req)
-}
-
-// VerifyNotBefore compares the nbf claim against cmp (cmp >= nbf).
-// If req is false, it will return true, if nbf is unset.
-func (c *RegisteredClaims) VerifyNotBefore(cmp time.Time, req bool) bool {
-	if c.NotBefore == nil {
-		return verifyNbf(nil, cmp, req)
-	}
-
-	return verifyNbf(&c.NotBefore.Time, cmp, req)
-}
-
-// VerifyIssuer compares the iss claim against cmp.
-// If required is false, this method will return true if the value matches or is unset
-func (c *RegisteredClaims) VerifyIssuer(cmp string, req bool) bool {
-	return verifyIss(c.Issuer, cmp, req)
-}
-
-// StandardClaims are a structured version of the JWT Claims Set, as referenced at
-// https://datatracker.ietf.org/doc/html/rfc7519#section-4. They do not follow the
-// specification exactly, since they were based on an earlier draft of the
-// specification and not updated. The main difference is that they only
-// support integer-based date fields and singular audiences. This might lead to
-// incompatibilities with other JWT implementations. The use of this is discouraged, instead
-// the newer RegisteredClaims struct should be used.
-//
-// Deprecated: Use RegisteredClaims instead for a forward-compatible way to access registered claims in a struct.
-type StandardClaims struct {
-	Audience  string `json:"aud,omitempty"`
-	ExpiresAt int64  `json:"exp,omitempty"`
-	Id        string `json:"jti,omitempty"`
-	IssuedAt  int64  `json:"iat,omitempty"`
-	Issuer    string `json:"iss,omitempty"`
-	NotBefore int64  `json:"nbf,omitempty"`
-	Subject   string `json:"sub,omitempty"`
-}
-
-// Valid validates time based claims "exp, iat, nbf". There is no accounting for clock skew.
-// As well, if any of the above claims are not in the token, it will still
-// be considered a valid claim.
-func (c StandardClaims) Valid() error {
-	vErr := new(ValidationError)
-	now := TimeFunc().Unix()
-
-	// The claims below are optional, by default, so if they are set to the
-	// default value in Go, let's not fail the verification for them.
-	if !c.VerifyExpiresAt(now, false) {
-		delta := time.Unix(now, 0).Sub(time.Unix(c.ExpiresAt, 0))
-		vErr.Inner = fmt.Errorf("%s by %s", ErrTokenExpired, delta)
-		vErr.Errors |= ValidationErrorExpired
-	}
-
-	if !c.VerifyIssuedAt(now, false) {
-		vErr.Inner = ErrTokenUsedBeforeIssued
-		vErr.Errors |= ValidationErrorIssuedAt
-	}
-
-	if !c.VerifyNotBefore(now, false) {
-		vErr.Inner = ErrTokenNotValidYet
-		vErr.Errors |= ValidationErrorNotValidYet
-	}
-
-	if vErr.valid() {
-		return nil
-	}
-
-	return vErr
-}
-
-// VerifyAudience compares the aud claim against cmp.
-// If required is false, this method will return true if the value matches or is unset
-func (c *StandardClaims) VerifyAudience(cmp string, req bool) bool {
-	return verifyAud([]string{c.Audience}, cmp, req)
-}
-
-// VerifyExpiresAt compares the exp claim against cmp (cmp < exp).
-// If req is false, it will return true, if exp is unset.
-func (c *StandardClaims) VerifyExpiresAt(cmp int64, req bool) bool {
-	if c.ExpiresAt == 0 {
-		return verifyExp(nil, time.Unix(cmp, 0), req)
-	}
-
-	t := time.Unix(c.ExpiresAt, 0)
-	return verifyExp(&t, time.Unix(cmp, 0), req)
-}
-
-// VerifyIssuedAt compares the iat claim against cmp (cmp >= iat).
-// If req is false, it will return true, if iat is unset.
-func (c *StandardClaims) VerifyIssuedAt(cmp int64, req bool) bool {
-	if c.IssuedAt == 0 {
-		return verifyIat(nil, time.Unix(cmp, 0), req)
-	}
-
-	t := time.Unix(c.IssuedAt, 0)
-	return verifyIat(&t, time.Unix(cmp, 0), req)
-}
-
-// VerifyNotBefore compares the nbf claim against cmp (cmp >= nbf).
-// If req is false, it will return true, if nbf is unset.
-func (c *StandardClaims) VerifyNotBefore(cmp int64, req bool) bool {
-	if c.NotBefore == 0 {
-		return verifyNbf(nil, time.Unix(cmp, 0), req)
-	}
-
-	t := time.Unix(c.NotBefore, 0)
-	return verifyNbf(&t, time.Unix(cmp, 0), req)
-}
-
-// VerifyIssuer compares the iss claim against cmp.
-// If required is false, this method will return true if the value matches or is unset
-func (c *StandardClaims) VerifyIssuer(cmp string, req bool) bool {
-	return verifyIss(c.Issuer, cmp, req)
-}
-
-// ----- helpers
-
-func verifyAud(aud []string, cmp string, required bool) bool {
-	if len(aud) == 0 {
-		return !required
-	}
-	// use a var here to keep constant time compare when looping over a number of claims
-	result := false
-
-	var stringClaims string
-	for _, a := range aud {
-		if subtle.ConstantTimeCompare([]byte(a), []byte(cmp)) != 0 {
-			result = true
-		}
-		stringClaims = stringClaims + a
-	}
-
-	// case where "" is sent in one or many aud claims
-	if len(stringClaims) == 0 {
-		return !required
-	}
-
-	return result
-}
-
-func verifyExp(exp *time.Time, now time.Time, required bool) bool {
-	if exp == nil {
-		return !required
-	}
-	return now.Before(*exp)
-}
-
-func verifyIat(iat *time.Time, now time.Time, required bool) bool {
-	if iat == nil {
-		return !required
-	}
-	return now.After(*iat) || now.Equal(*iat)
-}
-
-func verifyNbf(nbf *time.Time, now time.Time, required bool) bool {
-	if nbf == nil {
-		return !required
-	}
-	return now.After(*nbf) || now.Equal(*nbf)
-}
-
-func verifyIss(iss string, cmp string, required bool) bool {
-	if iss == "" {
-		return !required
-	}
-	if subtle.ConstantTimeCompare([]byte(iss), []byte(cmp)) != 0 {
-		return true
-	} else {
-		return false
-	}
+	GetExpirationTime() (*NumericDate, error)
+	GetIssuedAt() (*NumericDate, error)
+	GetNotBefore() (*NumericDate, error)
+	GetIssuer() (string, error)
+	GetSubject() (string, error)
+	GetAudience() (ClaimStrings, error)
 }

cmd/jwt/README.md

@@ -16,4 +16,4 @@ To simply display a token, use:
 
 You can install this tool with the following command:
 
-     go install github.com/golang-jwt/jwt/v4/cmd/jwt
+     go install github.com/golang-jwt/jwt/v5/cmd/jwt

cmd/jwt/main.go

@@ -17,7 +17,7 @@ import (
 	"sort"
 	"strings"
 
-	"github.com/golang-jwt/jwt/v4"
+	"github.com/golang-jwt/jwt/v5"
 )
 
 var (

ecdsa_test.go

@@ -6,7 +6,7 @@ import (
 	"strings"
 	"testing"
 
-	"github.com/golang-jwt/jwt/v4"
+	"github.com/golang-jwt/jwt/v5"
 )
 
 var ecdsaTestData = []struct {

ed25519_test.go

@@ -5,7 +5,7 @@ import (
 	"strings"
 	"testing"
 
-	"github.com/golang-jwt/jwt/v4"
+	"github.com/golang-jwt/jwt/v5"
 )
 
 var ed25519TestData = []struct {

errors.go

@@ -18,6 +18,7 @@ var (
 	ErrTokenExpired          = errors.New("token is expired")
 	ErrTokenUsedBeforeIssued = errors.New("token used before issued")
 	ErrTokenInvalidIssuer    = errors.New("token has invalid issuer")
+	ErrTokenInvalidSubject   = errors.New("token has invalid subject")
 	ErrTokenNotValidYet      = errors.New("token is not valid yet")
 	ErrTokenInvalidId        = errors.New("token has invalid id")
 	ErrTokenInvalidClaims    = errors.New("token has invalid claims")
@@ -29,11 +30,12 @@ const (
 	ValidationErrorUnverifiable                        // Token could not be verified because of signing problems
 	ValidationErrorSignatureInvalid                    // Signature validation failed
 
-	// Standard Claim validation errors
+	// Registered Claim validation errors
 	ValidationErrorAudience      // AUD validation failed
 	ValidationErrorExpired       // EXP validation failed
 	ValidationErrorIssuedAt      // IAT validation failed
 	ValidationErrorIssuer        // ISS validation failed
+	ValidationErrorSubject       // SUB validation failed
 	ValidationErrorNotValidYet   // NBF validation failed
 	ValidationErrorId            // JTI validation failed
 	ValidationErrorClaimsInvalid // Generic claims validation error

example_test.go

@@ -5,7 +5,7 @@ import (
 	"fmt"
 	"time"
 
-	"github.com/golang-jwt/jwt/v4"
+	"github.com/golang-jwt/jwt/v5"
 )
 
 // Example (atypical) using the RegisteredClaims type by itself to parse a token.
@@ -70,7 +70,7 @@ func ExampleNewWithClaims_customClaimsType() {
 	//Output: eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJmb28iOiJiYXIiLCJpc3MiOiJ0ZXN0IiwiZXhwIjoxNTE2MjM5MDIyfQ.xVuY2FZ_MRXMIEgVQ7J-TFtaucVFRXUzHm9LmV41goM <nil>
 }
 
-// Example creating a token using a custom claims type.  The StandardClaim is embedded
+// Example creating a token using a custom claims type.  The RegisteredClaims is embedded
 // in the custom type to allow for easy encoding, parsing and validation of standard claims.
 func ExampleParseWithClaims_customClaimsType() {
 	tokenString := "eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJmb28iOiJiYXIiLCJpc3MiOiJ0ZXN0IiwiYXVkIjoic2luZ2xlIn0.QAWg1vGvnqRuCFTMcPkjZljXHh8U3L_qUjszOtQbeaA"
@@ -93,7 +93,65 @@ func ExampleParseWithClaims_customClaimsType() {
 	// Output: bar test
 }
 
-// An example of parsing the error types using bitfield checks
+// Example creating a token using a custom claims type and validation options.  The RegisteredClaims is embedded
+// in the custom type to allow for easy encoding, parsing and validation of standard claims.
+func ExampleParseWithClaims_validationOptions() {
+	tokenString := "eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJmb28iOiJiYXIiLCJpc3MiOiJ0ZXN0IiwiYXVkIjoic2luZ2xlIn0.QAWg1vGvnqRuCFTMcPkjZljXHh8U3L_qUjszOtQbeaA"
+
+	type MyCustomClaims struct {
+		Foo string `json:"foo"`
+		jwt.RegisteredClaims
+	}
+
+	validator := jwt.NewValidator(jwt.WithLeeway(5 * time.Second))
+	token, err := jwt.ParseWithClaims(tokenString, &MyCustomClaims{}, func(token *jwt.Token) (interface{}, error) {
+		return []byte("AllYourBase"), nil
+	}, jwt.WithValidator(validator))
+
+	if claims, ok := token.Claims.(*MyCustomClaims); ok && token.Valid {
+		fmt.Printf("%v %v", claims.Foo, claims.RegisteredClaims.Issuer)
+	} else {
+		fmt.Println(err)
+	}
+
+	// Output: bar test
+}
+
+type MyCustomClaims struct {
+	Foo string `json:"foo"`
+	jwt.RegisteredClaims
+}
+
+func (m MyCustomClaims) CustomValidation() error {
+	if m.Foo != "bar" {
+		return errors.New("must be foobar")
+	}
+
+	return nil
+}
+
+// Example creating a token using a custom claims type and validation options.
+// The RegisteredClaims is embedded in the custom type to allow for easy
+// encoding, parsing and validation of standard claims and the function
+// CustomValidation is implemented.
+func ExampleParseWithClaims_customValidation() {
+	tokenString := "eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJmb28iOiJiYXIiLCJpc3MiOiJ0ZXN0IiwiYXVkIjoic2luZ2xlIn0.QAWg1vGvnqRuCFTMcPkjZljXHh8U3L_qUjszOtQbeaA"
+
+	validator := jwt.NewValidator(jwt.WithLeeway(5 * time.Second))
+	token, err := jwt.ParseWithClaims(tokenString, &MyCustomClaims{}, func(token *jwt.Token) (interface{}, error) {
+		return []byte("AllYourBase"), nil
+	}, jwt.WithValidator(validator))
+
+	if claims, ok := token.Claims.(*MyCustomClaims); ok && token.Valid {
+		fmt.Printf("%v %v", claims.Foo, claims.RegisteredClaims.Issuer)
+	} else {
+		fmt.Println(err)
+	}
+
+	// Output: bar test
+}
+
+// An example of parsing the error types using errors.Is.
 func ExampleParse_errorChecking() {
 	// Token from another example.  This token is expired
 	var tokenString = "eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJmb28iOiJiYXIiLCJleHAiOjE1MDAwLCJpc3MiOiJ0ZXN0In0.HE7fK0xOQwFEr4WDgRWj4teRPZ6i3GLwD5YCm6Pwu_c"

go.mod

@@ -1,7 +1,3 @@
-module github.com/golang-jwt/jwt/v4
+module github.com/golang-jwt/jwt/v5
 
 go 1.16
-
-retract (
-    v4.4.0 // Contains a backwards incompatible change to the Claims interface.
-)

hmac_example_test.go

@@ -5,7 +5,7 @@ import (
 	"os"
 	"time"
 
-	"github.com/golang-jwt/jwt/v4"
+	"github.com/golang-jwt/jwt/v5"
 )
 
 // For HMAC signing method, the key can be any []byte. It is recommended to generate

hmac_test.go

@@ -5,7 +5,7 @@ import (
 	"strings"
 	"testing"
 
-	"github.com/golang-jwt/jwt/v4"
+	"github.com/golang-jwt/jwt/v5"
 )
 
 var hmacTestData = []struct {

http_example_test.go

@@ -16,8 +16,8 @@ import (
 	"strings"
 	"time"
 
-	"github.com/golang-jwt/jwt/v4"
-	"github.com/golang-jwt/jwt/v4/request"
+	"github.com/golang-jwt/jwt/v5"
+	"github.com/golang-jwt/jwt/v5/request"
 )
 
 // location of the files used for signing and verification

map_claims.go

@@ -3,149 +3,109 @@ package jwt
 import (
 	"encoding/json"
 	"errors"
-	"time"
-	// "fmt"
 )
 
 // MapClaims is a claims type that uses the map[string]interface{} for JSON decoding.
 // This is the default claims type if you don't supply one
 type MapClaims map[string]interface{}
 
-// VerifyAudience Compares the aud claim against cmp.
-// If required is false, this method will return true if the value matches or is unset
-func (m MapClaims) VerifyAudience(cmp string, req bool) bool {
-	var aud []string
-	switch v := m["aud"].(type) {
-	case string:
-		aud = append(aud, v)
-	case []string:
-		aud = v
-	case []interface{}:
-		for _, a := range v {
-			vs, ok := a.(string)
-			if !ok {
-				return false
-			}
-			aud = append(aud, vs)
-		}
-	}
-	return verifyAud(aud, cmp, req)
+var ErrInvalidType = errors.New("invalid type for claim")
+
+// GetExpirationTime implements the Claims interface.
+func (m MapClaims) GetExpirationTime() (*NumericDate, error) {
+	return m.ParseNumericDate("exp")
 }
 
-// VerifyExpiresAt compares the exp claim against cmp (cmp <= exp).
-// If req is false, it will return true, if exp is unset.
-func (m MapClaims) VerifyExpiresAt(cmp int64, req bool) bool {
-	cmpTime := time.Unix(cmp, 0)
+// GetNotBefore implements the Claims interface.
+func (m MapClaims) GetNotBefore() (*NumericDate, error) {
+	return m.ParseNumericDate("nbf")
+}
 
-	v, ok := m["exp"]
+// GetIssuedAt implements the Claims interface.
+func (m MapClaims) GetIssuedAt() (*NumericDate, error) {
+	return m.ParseNumericDate("iat")
+}
+
+// GetAudience implements the Claims interface.
+func (m MapClaims) GetAudience() (ClaimStrings, error) {
+	return m.ParseClaimsString("aud")
+}
+
+// GetIssuer implements the Claims interface.
+func (m MapClaims) GetIssuer() (string, error) {
+	return m.ParseString("iss")
+}
+
+// GetSubject implements the Claims interface.
+func (m MapClaims) GetSubject() (string, error) {
+	return m.ParseString("sub")
+}
+
+// ParseNumericDate tries to parse a key in the map claims type as a number
+// date. This will succeed, if the underlying type is either a [float64] or a
+// [json.Number]. Otherwise, nil will be returned.
+func (m MapClaims) ParseNumericDate(key string) (*NumericDate, error) {
+	v, ok := m[key]
 	if !ok {
-		return !req
+		return nil, nil
 	}
 
 	switch exp := v.(type) {
 	case float64:
 		if exp == 0 {
-			return verifyExp(nil, cmpTime, req)
+			return nil, nil
 		}
 
-		return verifyExp(&newNumericDateFromSeconds(exp).Time, cmpTime, req)
+		return newNumericDateFromSeconds(exp), nil
 	case json.Number:
 		v, _ := exp.Float64()
 
-		return verifyExp(&newNumericDateFromSeconds(v).Time, cmpTime, req)
+		return newNumericDateFromSeconds(v), nil
 	}
 
-	return false
+	return nil, ErrInvalidType
 }
 
-// VerifyIssuedAt compares the exp claim against cmp (cmp >= iat).
-// If req is false, it will return true, if iat is unset.
-func (m MapClaims) VerifyIssuedAt(cmp int64, req bool) bool {
-	cmpTime := time.Unix(cmp, 0)
-
-	v, ok := m["iat"]
+// ParseClaimsString tries to parse a key in the map claims type as a
+// [ClaimsStrings] type, which can either be a string or an array of string.
+func (m MapClaims) ParseClaimsString(key string) (ClaimStrings, error) {
+	var cs []string
+	switch v := m[key].(type) {
+	case string:
+		cs = append(cs, v)
+	case []string:
+		cs = v
+	case []interface{}:
+		for _, a := range v {
+			vs, ok := a.(string)
 			if !ok {
-		return !req
+				return nil, ErrInvalidType
+			}
+			cs = append(cs, vs)
+		}
 	}
 
-	switch iat := v.(type) {
-	case float64:
-		if iat == 0 {
-			return verifyIat(nil, cmpTime, req)
-		}
-
-		return verifyIat(&newNumericDateFromSeconds(iat).Time, cmpTime, req)
-	case json.Number:
-		v, _ := iat.Float64()
-
-		return verifyIat(&newNumericDateFromSeconds(v).Time, cmpTime, req)
-	}
-
-	return false
+	return cs, nil
 }
 
-// VerifyNotBefore compares the nbf claim against cmp (cmp >= nbf).
-// If req is false, it will return true, if nbf is unset.
-func (m MapClaims) VerifyNotBefore(cmp int64, req bool) bool {
-	cmpTime := time.Unix(cmp, 0)
-
-	v, ok := m["nbf"]
+// ParseString tries to parse a key in the map claims type as a [string] type.
+// If the key does not exist, an empty string is returned. If the key has the
+// wrong type, an error is returned.
+func (m MapClaims) ParseString(key string) (string, error) {
+	var (
+		ok  bool
+		raw interface{}
+		iss string
+	)
+	raw, ok = m[key]
 	if !ok {
-		return !req
+		return "", nil
 	}
 
-	switch nbf := v.(type) {
-	case float64:
-		if nbf == 0 {
-			return verifyNbf(nil, cmpTime, req)
+	iss, ok = raw.(string)
+	if !ok {
+		return "", ErrInvalidType
 	}
 
-		return verifyNbf(&newNumericDateFromSeconds(nbf).Time, cmpTime, req)
-	case json.Number:
-		v, _ := nbf.Float64()
-
-		return verifyNbf(&newNumericDateFromSeconds(v).Time, cmpTime, req)
-	}
-
-	return false
-}
-
-// VerifyIssuer compares the iss claim against cmp.
-// If required is false, this method will return true if the value matches or is unset
-func (m MapClaims) VerifyIssuer(cmp string, req bool) bool {
-	iss, _ := m["iss"].(string)
-	return verifyIss(iss, cmp, req)
-}
-
-// Valid validates time based claims "exp, iat, nbf".
-// There is no accounting for clock skew.
-// As well, if any of the above claims are not in the token, it will still
-// be considered a valid claim.
-func (m MapClaims) Valid() error {
-	vErr := new(ValidationError)
-	now := TimeFunc().Unix()
-
-	if !m.VerifyExpiresAt(now, false) {
-		// TODO(oxisto): this should be replaced with ErrTokenExpired
-		vErr.Inner = errors.New("Token is expired")
-		vErr.Errors |= ValidationErrorExpired
-	}
-
-	if !m.VerifyIssuedAt(now, false) {
-		// TODO(oxisto): this should be replaced with ErrTokenUsedBeforeIssued
-		vErr.Inner = errors.New("Token used before issued")
-		vErr.Errors |= ValidationErrorIssuedAt
-	}
-
-	if !m.VerifyNotBefore(now, false) {
-		// TODO(oxisto): this should be replaced with ErrTokenNotValidYet
-		vErr.Inner = errors.New("Token is not valid yet")
-		vErr.Errors |= ValidationErrorNotValidYet
-	}
-
-	if vErr.valid() {
-		return nil
-	}
-
-	return vErr
+	return iss, nil
 }

map_claims_test.go

@@ -42,7 +42,7 @@ func TestVerifyAud(t *testing.T) {
 		{Name: "[]String Aud without match not required", MapClaims: MapClaims{"aud": []string{"not.example.com", "example.example.com"}}, Expected: false, Required: true, Comparison: "example.com"},
 
 		// Required = false
-		{Name: "Empty []String Aud without match required", MapClaims: MapClaims{"aud": []string{""}}, Expected: false, Required: true, Comparison: "example.com"},
+		{Name: "Empty []String Aud without match required", MapClaims: MapClaims{"aud": []string{""}}, Expected: true, Required: false, Comparison: "example.com"},
 
 		// []interface{}
 		{Name: "Empty []interface{} Aud without match required", MapClaims: MapClaims{"aud": nilListInterface}, Expected: true, Required: false, Comparison: "example.com"},
@@ -56,10 +56,17 @@ func TestVerifyAud(t *testing.T) {
 
 	for _, test := range tests {
 		t.Run(test.Name, func(t *testing.T) {
-			got := test.MapClaims.VerifyAudience(test.Comparison, test.Required)
+			var opts []ValidatorOption
 
-			if got != test.Expected {
-				t.Errorf("Expected %v, got %v", test.Expected, got)
+			if test.Required {
+				opts = append(opts, WithAudience(test.Comparison))
+			}
+
+			validator := NewValidator(opts...)
+			got := validator.Validate(test.MapClaims)
+
+			if (got == nil) != test.Expected {
+				t.Errorf("Expected %v, got %v", test.Expected, (got == nil))
 			}
 		})
 	}
@@ -70,9 +77,9 @@ func TestMapclaimsVerifyIssuedAtInvalidTypeString(t *testing.T) {
 		"iat": "foo",
 	}
 	want := false
-	got := mapClaims.VerifyIssuedAt(0, false)
-	if want != got {
-		t.Fatalf("Failed to verify claims, wanted: %v got %v", want, got)
+	got := NewValidator(WithIssuedAt()).Validate(mapClaims)
+	if want != (got == nil) {
+		t.Fatalf("Failed to verify claims, wanted: %v got %v", want, (got == nil))
 	}
 }
 
@@ -81,9 +88,9 @@ func TestMapclaimsVerifyNotBeforeInvalidTypeString(t *testing.T) {
 		"nbf": "foo",
 	}
 	want := false
-	got := mapClaims.VerifyNotBefore(0, false)
-	if want != got {
-		t.Fatalf("Failed to verify claims, wanted: %v got %v", want, got)
+	got := NewValidator().Validate(mapClaims)
+	if want != (got == nil) {
+		t.Fatalf("Failed to verify claims, wanted: %v got %v", want, (got == nil))
 	}
 }
 
@@ -92,32 +99,38 @@ func TestMapclaimsVerifyExpiresAtInvalidTypeString(t *testing.T) {
 		"exp": "foo",
 	}
 	want := false
-	got := mapClaims.VerifyExpiresAt(0, false)
+	got := NewValidator().Validate(mapClaims)
 
-	if want != got {
-		t.Fatalf("Failed to verify claims, wanted: %v got %v", want, got)
+	if want != (got == nil) {
+		t.Fatalf("Failed to verify claims, wanted: %v got %v", want, (got == nil))
 	}
 }
 
 func TestMapClaimsVerifyExpiresAtExpire(t *testing.T) {
-	exp := time.Now().Unix()
+	exp := time.Now()
 	mapClaims := MapClaims{
-		"exp": float64(exp),
+		"exp": float64(exp.Unix()),
 	}
 	want := false
-	got := mapClaims.VerifyExpiresAt(exp, true)
-	if want != got {
-		t.Fatalf("Failed to verify claims, wanted: %v got %v", want, got)
+	got := NewValidator(WithTimeFunc(func() time.Time {
+		return exp
+	})).Validate(mapClaims)
+	if want != (got == nil) {
+		t.Fatalf("Failed to verify claims, wanted: %v got %v", want, (got == nil))
 	}
 
-	got = mapClaims.VerifyExpiresAt(exp+1, true)
-	if want != got {
-		t.Fatalf("Failed to verify claims, wanted: %v got %v", want, got)
+	got = NewValidator(WithTimeFunc(func() time.Time {
+		return exp.Add(1 * time.Second)
+	})).Validate(mapClaims)
+	if want != (got == nil) {
+		t.Fatalf("Failed to verify claims, wanted: %v got %v", want, (got == nil))
 	}
 
 	want = true
-	got = mapClaims.VerifyExpiresAt(exp-1, true)
-	if want != got {
-		t.Fatalf("Failed to verify claims, wanted: %v got %v", want, got)
+	got = NewValidator(WithTimeFunc(func() time.Time {
+		return exp.Add(-1 * time.Second)
+	})).Validate(mapClaims)
+	if want != (got == nil) {
+		t.Fatalf("Failed to verify claims, wanted: %v got %v", want, (got == nil))
 	}
 }

none_test.go

@@ -4,7 +4,7 @@ import (
 	"strings"
 	"testing"
 
-	"github.com/golang-jwt/jwt/v4"
+	"github.com/golang-jwt/jwt/v5"
 )
 
 var noneTestData = []struct {

parser.go

@@ -22,13 +22,15 @@ type Parser struct {
 	//
 	// Deprecated: In future releases, this field will not be exported anymore and should be set with an option to NewParser instead.
 	SkipClaimsValidation bool
+
+	validator *Validator
 }
 
 // NewParser creates a new Parser with the specified options
 func NewParser(options ...ParserOption) *Parser {
 	p := &Parser{}
 
-	// loop through our parsing options and apply them
+	// Loop through our parsing options and apply them
 	for _, option := range options {
 		option(p)
 	}
@@ -82,8 +84,12 @@ func (p *Parser) ParseWithClaims(tokenString string, claims Claims, keyFunc Keyf
 
 	// Validate Claims
 	if !p.SkipClaimsValidation {
-		if err := token.Claims.Valid(); err != nil {
+		// Make sure we have at least a default validator
+		if p.validator == nil {
+			p.validator = NewValidator()
+		}
 
+		if err := p.validator.Validate(claims); err != nil {
 			// If the Claims Valid returned an error, check if it is a validation error,
 			// If it was another error type, create a ValidationError with a generic ClaimsInvalid flag set
 			if e, ok := err.(*ValidationError); !ok {

parser_option.go

@@ -27,3 +27,10 @@ func WithoutClaimsValidation() ParserOption {
 		p.SkipClaimsValidation = true
 	}
 }
+
+// WithValidator is an option to include a claims validator.
+func WithValidator(v *Validator) ParserOption {
+	return func(p *Parser) {
+		p.validator = v
+	}
+}

parser_test.go

@@ -10,8 +10,8 @@ import (
 	"testing"
 	"time"
 
-	"github.com/golang-jwt/jwt/v4"
-	"github.com/golang-jwt/jwt/v4/test"
+	"github.com/golang-jwt/jwt/v5"
+	"github.com/golang-jwt/jwt/v5/test"
 )
 
 var errKeyFuncError error = fmt.Errorf("error loading key")
@@ -199,19 +199,6 @@ var jwtTestData = []struct {
 		&jwt.Parser{UseJSONNumber: true},
 		jwt.SigningMethodRS256,
 	},
-	{
-		"Standard Claims",
-		"",
-		defaultKeyFunc,
-		&jwt.StandardClaims{
-			ExpiresAt: time.Now().Add(time.Second * 10).Unix(),
-		},
-		true,
-		0,
-		nil,
-		&jwt.Parser{UseJSONNumber: true},
-		jwt.SigningMethodRS256,
-	},
 	{
 		"JSON Number - basic expired",
 		"", // autogen
@@ -321,6 +308,28 @@ var jwtTestData = []struct {
 		&jwt.Parser{UseJSONNumber: true},
 		jwt.SigningMethodRS256,
 	},
+	{
+		"RFC7519 Claims - nbf with 60s skew",
+		"", // autogen
+		defaultKeyFunc,
+		&jwt.RegisteredClaims{NotBefore: jwt.NewNumericDate(time.Now().Add(time.Second * 100))},
+		false,
+		jwt.ValidationErrorNotValidYet,
+		[]error{jwt.ErrTokenNotValidYet},
+		jwt.NewParser(jwt.WithValidator(jwt.NewValidator(jwt.WithLeeway(time.Minute)))),
+		jwt.SigningMethodRS256,
+	},
+	{
+		"RFC7519 Claims - nbf with 120s skew",
+		"", // autogen
+		defaultKeyFunc,
+		&jwt.RegisteredClaims{NotBefore: jwt.NewNumericDate(time.Now().Add(time.Second * 100))},
+		true,
+		0,
+		nil,
+		jwt.NewParser(jwt.WithValidator(jwt.NewValidator(jwt.WithLeeway(2 * time.Minute)))),
+		jwt.SigningMethodRS256,
+	},
 }
 
 // signToken creates and returns a signed JWT token using signingMethod.
@@ -354,14 +363,12 @@ func TestParser_Parse(t *testing.T) {
 			var err error
 			var parser = data.parser
 			if parser == nil {
-				parser = new(jwt.Parser)
+				parser = jwt.NewParser()
 			}
 			// Figure out correct claims type
 			switch data.claims.(type) {
 			case jwt.MapClaims:
 				token, err = parser.ParseWithClaims(data.tokenString, jwt.MapClaims{}, data.keyfunc)
-			case *jwt.StandardClaims:
-				token, err = parser.ParseWithClaims(data.tokenString, &jwt.StandardClaims{}, data.keyfunc)
 			case *jwt.RegisteredClaims:
 				token, err = parser.ParseWithClaims(data.tokenString, &jwt.RegisteredClaims{}, data.keyfunc)
 			}
@@ -454,8 +461,6 @@ func TestParser_ParseUnverified(t *testing.T) {
 			switch data.claims.(type) {
 			case jwt.MapClaims:
 				token, _, err = parser.ParseUnverified(data.tokenString, jwt.MapClaims{})
-			case *jwt.StandardClaims:
-				token, _, err = parser.ParseUnverified(data.tokenString, &jwt.StandardClaims{})
 			case *jwt.RegisteredClaims:
 				token, _, err = parser.ParseUnverified(data.tokenString, &jwt.RegisteredClaims{})
 			}
@@ -605,9 +610,9 @@ func BenchmarkParseUnverified(b *testing.B) {
 			b.Run("map_claims", func(b *testing.B) {
 				benchmarkParsing(b, parser, data.tokenString, jwt.MapClaims{})
 			})
-		case *jwt.StandardClaims:
-			b.Run("standard_claims", func(b *testing.B) {
-				benchmarkParsing(b, parser, data.tokenString, &jwt.StandardClaims{})
+		case *jwt.RegisteredClaims:
+			b.Run("registered_claims", func(b *testing.B) {
+				benchmarkParsing(b, parser, data.tokenString, &jwt.RegisteredClaims{})
 			})
 		}
 	}

registered_claims.go

@@ -0,0 +1,63 @@
+package jwt
+
+// RegisteredClaims are a structured version of the JWT Claims Set,
+// restricted to Registered Claim Names, as referenced at
+// https://datatracker.ietf.org/doc/html/rfc7519#section-4.1
+//
+// This type can be used on its own, but then additional private and
+// public claims embedded in the JWT will not be parsed. The typical use-case
+// therefore is to embedded this in a user-defined claim type.
+//
+// See examples for how to use this with your own claim types.
+type RegisteredClaims struct {
+	// the `iss` (Issuer) claim. See https://datatracker.ietf.org/doc/html/rfc7519#section-4.1.1
+	Issuer string `json:"iss,omitempty"`
+
+	// the `sub` (Subject) claim. See https://datatracker.ietf.org/doc/html/rfc7519#section-4.1.2
+	Subject string `json:"sub,omitempty"`
+
+	// the `aud` (Audience) claim. See https://datatracker.ietf.org/doc/html/rfc7519#section-4.1.3
+	Audience ClaimStrings `json:"aud,omitempty"`
+
+	// the `exp` (Expiration Time) claim. See https://datatracker.ietf.org/doc/html/rfc7519#section-4.1.4
+	ExpiresAt *NumericDate `json:"exp,omitempty"`
+
+	// the `nbf` (Not Before) claim. See https://datatracker.ietf.org/doc/html/rfc7519#section-4.1.5
+	NotBefore *NumericDate `json:"nbf,omitempty"`
+
+	// the `iat` (Issued At) claim. See https://datatracker.ietf.org/doc/html/rfc7519#section-4.1.6
+	IssuedAt *NumericDate `json:"iat,omitempty"`
+
+	// the `jti` (JWT ID) claim. See https://datatracker.ietf.org/doc/html/rfc7519#section-4.1.7
+	ID string `json:"jti,omitempty"`
+}
+
+// GetExpirationTime implements the Claims interface.
+func (c RegisteredClaims) GetExpirationTime() (*NumericDate, error) {
+	return c.ExpiresAt, nil
+}
+
+// GetNotBefore implements the Claims interface.
+func (c RegisteredClaims) GetNotBefore() (*NumericDate, error) {
+	return c.NotBefore, nil
+}
+
+// GetIssuedAt implements the Claims interface.
+func (c RegisteredClaims) GetIssuedAt() (*NumericDate, error) {
+	return c.IssuedAt, nil
+}
+
+// GetAudience implements the Claims interface.
+func (c RegisteredClaims) GetAudience() (ClaimStrings, error) {
+	return c.Audience, nil
+}
+
+// GetIssuer implements the Claims interface.
+func (c RegisteredClaims) GetIssuer() (string, error) {
+	return c.Issuer, nil
+}
+
+// GetSubject implements the Claims interface.
+func (c RegisteredClaims) GetSubject() (string, error) {
+	return c.Subject, nil
+}

request/request.go

@@ -3,7 +3,7 @@ package request
 import (
 	"net/http"
 
-	"github.com/golang-jwt/jwt/v4"
+	"github.com/golang-jwt/jwt/v5"
 )
 
 // ParseFromRequest extracts and parses a JWT token from an HTTP request.

request/request_test.go

@@ -8,8 +8,8 @@ import (
 	"strings"
 	"testing"
 
-	"github.com/golang-jwt/jwt/v4"
-	"github.com/golang-jwt/jwt/v4/test"
+	"github.com/golang-jwt/jwt/v5"
+	"github.com/golang-jwt/jwt/v5/test"
 )
 
 var requestTestData = []struct {

rsa_pss_test.go

@@ -10,8 +10,8 @@ import (
 	"testing"
 	"time"
 
-	"github.com/golang-jwt/jwt/v4"
-	"github.com/golang-jwt/jwt/v4/test"
+	"github.com/golang-jwt/jwt/v5"
+	"github.com/golang-jwt/jwt/v5/test"
 )
 
 var rsaPSSTestData = []struct {

rsa_test.go

@@ -5,7 +5,7 @@ import (
 	"strings"
 	"testing"
 
-	"github.com/golang-jwt/jwt/v4"
+	"github.com/golang-jwt/jwt/v5"
 )
 
 var rsaTestData = []struct {

test/helpers.go

@@ -5,7 +5,7 @@ import (
 	"crypto/rsa"
 	"os"
 
-	"github.com/golang-jwt/jwt/v4"
+	"github.com/golang-jwt/jwt/v5"
 )
 
 func LoadRSAPrivateKeyFromDisk(location string) *rsa.PrivateKey {

token.go

@@ -4,7 +4,6 @@ import (
 	"encoding/base64"
 	"encoding/json"
 	"strings"
-	"time"
 )
 
 // DecodePaddingAllowed will switch the codec used for decoding JWTs respectively. Note that the JWS RFC7515
@@ -14,11 +13,6 @@ import (
 // To use the non-recommended decoding, set this boolean to `true` prior to using this package.
 var DecodePaddingAllowed bool
 
-// TimeFunc provides the current time when parsing token to validate "exp" claim (expiration time).
-// You can override it to use another time value.  This is useful for testing or if your
-// server uses a different time zone than your tokens.
-var TimeFunc = time.Now
-
 // Keyfunc will be used by the Parse methods as a callback function to supply
 // the key for verification.  The function receives the parsed,
 // but unverified Token.  This allows you to use properties in the

token_test.go

@@ -3,7 +3,7 @@ package jwt_test
 import (
 	"testing"
 
-	"github.com/golang-jwt/jwt/v4"
+	"github.com/golang-jwt/jwt/v5"
 )
 
 func TestToken_SigningString(t1 *testing.T) {
@@ -30,7 +30,7 @@ func TestToken_SigningString(t1 *testing.T) {
 					"typ": "JWT",
 					"alg": jwt.SigningMethodHS256.Alg(),
 				},
-				Claims:    jwt.StandardClaims{},
+				Claims:    jwt.RegisteredClaims{},
 				Signature: "",
 				Valid:     false,
 			},
@@ -67,7 +67,7 @@ func BenchmarkToken_SigningString(b *testing.B) {
 			"typ": "JWT",
 			"alg": jwt.SigningMethodHS256.Alg(),
 		},
-		Claims: jwt.StandardClaims{},
+		Claims: jwt.RegisteredClaims{},
 	}
 	b.Run("BenchmarkToken_SigningString", func(b *testing.B) {
 		b.ResetTimer()

types_test.go

@@ -6,7 +6,7 @@ import (
 	"testing"
 	"time"
 
-	"github.com/golang-jwt/jwt/v4"
+	"github.com/golang-jwt/jwt/v5"
 )
 
 func TestNumericDate(t *testing.T) {

validator.go

@@ -0,0 +1,265 @@
+package jwt
+
+import (
+	"crypto/subtle"
+	"time"
+)
+
+// Validator is the core of the new Validation API. It can either be used to
+// modify the validation used during parsing with the [WithValidator] parser
+// option or used standalone to validate an already parsed [Claim]. It can be
+// further customized with a range of specified [ValidatorOption]s.
+type Validator struct {
+	// leeway is an optional leeway that can be provided to account for clock skew.
+	leeway time.Duration
+
+	// timeFunc is used to supply the current time that is needed for
+	// validation. If unspecified, this defaults to time.Now.
+	timeFunc func() time.Time
+
+	// verifyIat specifies whether the iat (Issued At) claim will be verified.
+	// According to https://www.rfc-editor.org/rfc/rfc7519#section-4.1.6 this
+	// only specifies the age of the token, but no validation check is
+	// necessary. However, if wanted, it can be checked if the iat is
+	// unrealistic, i.e., in the future.
+	verifyIat bool
+
+	// expectedAud contains the audience this token expects. Supplying an empty
+	// string will disable aud checking.
+	expectedAud string
+
+	// expectedIss contains the issuer this token expects. Supplying an empty
+	// string will disable iss checking.
+	expectedIss string
+
+	expectedSubPattern PatternFunc
+}
+
+// CustomClaims represents a custom claims interface, which can be built upon the integrated
+// claim types, such as map claims or registered claims.
+type CustomClaims interface {
+	// CustomValidation can be implemented by a user-specific claim to support
+	// additional validation steps in addition to the regular validation.
+	CustomValidation() error
+}
+
+func NewValidator(opts ...ValidatorOption) *Validator {
+	v := &Validator{}
+
+	// Apply the validator options
+	for _, o := range opts {
+		o(v)
+	}
+
+	return v
+}
+
+// Validate validates the given claims. It will also perform any custom validation if claims implements the CustomValidator interface.
+func (v *Validator) Validate(claims Claims) error {
+	var now time.Time
+	vErr := new(ValidationError)
+
+	// Check, if we have a time func
+	if v.timeFunc != nil {
+		now = v.timeFunc()
+	} else {
+		now = time.Now()
+	}
+
+	// We always need to check the expiration time, but the claim itself is OPTIONAL
+	if !v.VerifyExpiresAt(claims, now, false) {
+		vErr.Inner = ErrTokenExpired
+		vErr.Errors |= ValidationErrorExpired
+	}
+
+	// We always need to check not-before, but the claim itself is OPTIONAL
+	if !v.VerifyNotBefore(claims, now, false) {
+		vErr.Inner = ErrTokenNotValidYet
+		vErr.Errors |= ValidationErrorNotValidYet
+	}
+
+	// Check issued-at if the option is enabled
+	if v.verifyIat && !v.VerifyIssuedAt(claims, now, false) {
+		vErr.Inner = ErrTokenUsedBeforeIssued
+		vErr.Errors |= ValidationErrorIssuedAt
+	}
+
+	// If we have an expected audience, we also require the audience claim
+	if v.expectedAud != "" && !v.VerifyAudience(claims, v.expectedAud, true) {
+		vErr.Inner = ErrTokenInvalidAudience
+		vErr.Errors |= ValidationErrorAudience
+	}
+
+	// If we have an expected issuer, we also require the issuer claim
+	if v.expectedIss != "" && !v.VerifyIssuer(claims, v.expectedIss, true) {
+		vErr.Inner = ErrTokenInvalidIssuer
+		vErr.Errors |= ValidationErrorIssuer
+	}
+
+	// If we have an expected subject, we also require the subject claim
+	if v.expectedSubPattern != nil && !v.VerifySubject(claims, v.expectedSubPattern, true) {
+		vErr.Inner = ErrTokenInvalidSubject
+		vErr.Errors |= ValidationErrorSubject
+	}
+
+	// Finally, we want to give the claim itself some possibility to do some
+	// additional custom validation based on their custom claims
+	cvt, ok := claims.(CustomClaims)
+	if ok {
+		if err := cvt.CustomValidation(); err != nil {
+			vErr.Inner = err
+			vErr.Errors |= ValidationErrorClaimsInvalid
+		}
+	}
+
+	if vErr.valid() {
+		return nil
+	}
+
+	return vErr
+}
+
+// VerifyAudience compares the aud claim against cmp.
+// If required is false, this method will return true if the value matches or is unset
+func (v *Validator) VerifyAudience(claims Claims, cmp string, req bool) bool {
+	aud, err := claims.GetAudience()
+	if err != nil {
+		return false
+	}
+
+	return verifyAud(aud, cmp, req)
+}
+
+// VerifyExpiresAt compares the exp claim against cmp (cmp < exp).
+// If req is false, it will return true, if exp is unset.
+func (v *Validator) VerifyExpiresAt(claims Claims, cmp time.Time, req bool) bool {
+	var time *time.Time = nil
+
+	exp, err := claims.GetExpirationTime()
+	if err != nil {
+		return false
+	} else if exp != nil {
+		time = &exp.Time
+	}
+
+	return verifyExp(time, cmp, req, v.leeway)
+}
+
+// VerifyIssuedAt compares the iat claim against cmp (cmp >= iat).
+// If req is false, it will return true, if iat is unset.
+func (v *Validator) VerifyIssuedAt(claims Claims, cmp time.Time, req bool) bool {
+	var time *time.Time = nil
+
+	iat, err := claims.GetIssuedAt()
+	if err != nil {
+		return false
+	} else if iat != nil {
+		time = &iat.Time
+	}
+
+	return verifyIat(time, cmp, req, v.leeway)
+}
+
+// VerifyNotBefore compares the nbf claim against cmp (cmp >= nbf).
+// If req is false, it will return true, if nbf is unset.
+func (v *Validator) VerifyNotBefore(claims Claims, cmp time.Time, req bool) bool {
+	var time *time.Time = nil
+
+	nbf, err := claims.GetNotBefore()
+	if err != nil {
+		return false
+	} else if nbf != nil {
+		time = &nbf.Time
+	}
+
+	return verifyNbf(time, cmp, req, v.leeway)
+}
+
+// VerifyIssuer compares the iss claim against cmp.
+// If required is false, this method will return true if the value matches or is unset
+func (v *Validator) VerifyIssuer(claims Claims, cmp string, req bool) bool {
+	iss, err := claims.GetIssuer()
+	if err != nil {
+		return false
+	}
+
+	return verifyIss(iss, cmp, req)
+}
+
+// VerifySubject compares the sub claim against cmp.
+// If required is false, this method will return true if the value matches or is unset
+func (v *Validator) VerifySubject(claims Claims, cmp PatternFunc, req bool) bool {
+	iss, err := claims.GetSubject()
+	if err != nil {
+		return false
+	}
+
+	return verifySub(iss, cmp, req)
+}
+
+// ----- helpers
+
+func verifyAud(aud []string, cmp string, required bool) bool {
+	if len(aud) == 0 {
+		return !required
+	}
+	// use a var here to keep constant time compare when looping over a number of claims
+	result := false
+
+	var stringClaims string
+	for _, a := range aud {
+		if subtle.ConstantTimeCompare([]byte(a), []byte(cmp)) != 0 {
+			result = true
+		}
+		stringClaims = stringClaims + a
+	}
+
+	// case where "" is sent in one or many aud claims
+	if stringClaims == "" {
+		return !required
+	}
+
+	return result
+}
+
+func verifyExp(exp *time.Time, now time.Time, required bool, skew time.Duration) bool {
+	if exp == nil {
+		return !required
+	}
+
+	return now.Before((*exp).Add(+skew))
+}
+
+func verifyIat(iat *time.Time, now time.Time, required bool, skew time.Duration) bool {
+	if iat == nil {
+		return !required
+	}
+
+	t := iat.Add(-skew)
+	return !now.Before(t)
+}
+
+func verifyNbf(nbf *time.Time, now time.Time, required bool, skew time.Duration) bool {
+	if nbf == nil {
+		return !required
+	}
+
+	t := nbf.Add(-skew)
+	return !now.Before(t)
+}
+
+func verifyIss(iss string, cmp string, required bool) bool {
+	if iss == "" {
+		return !required
+	}
+
+	return iss == cmp
+}
+
+func verifySub(sub string, cmp PatternFunc, required bool) bool {
+	if sub == "" {
+		return !required
+	}
+
+	return cmp(sub)
+}

validator_option.go

@@ -0,0 +1,96 @@
+package jwt
+
+import (
+	"strings"
+	"time"
+)
+
+// ValidatorOption is used to implement functional-style options that modify the
+// behavior of the validator. To add new options, just create a function
+// (ideally beginning with With or Without) that returns an anonymous function
+// that takes a *Parser type as input and manipulates its configuration
+// accordingly.
+type ValidatorOption func(*Validator)
+
+type PatternFunc func(s string) bool
+
+func HasPrefix(prefix string) PatternFunc {
+	return func(s string) bool {
+		return strings.HasPrefix(s, prefix)
+	}
+}
+
+func Equals(cmp string) PatternFunc {
+	return func(s string) bool {
+		return cmp == s
+	}
+}
+
+// WithLeeway returns the ValidatorOption for specifying the leeway window.
+func WithLeeway(leeway time.Duration) ValidatorOption {
+	return func(v *Validator) {
+		v.leeway = leeway
+	}
+}
+
+// WithTimeFunc returns the ValidatorOption for specifying the time func. The
+// primary use-case for this is testing. If you are looking for a way to account
+// for clock-skew, WithLeeway should be used instead.
+func WithTimeFunc(f func() time.Time) ValidatorOption {
+	return func(v *Validator) {
+		v.timeFunc = f
+	}
+}
+
+// WithIssuedAt returns the ValidatorOption to enable verification
+// of issued-at.
+func WithIssuedAt() ValidatorOption {
+	return func(v *Validator) {
+		v.verifyIat = true
+	}
+}
+
+// WithAudience configures the validator to require the specified audience in
+// the `aud` claim. Validation will fail if the audience is not listed in the
+// token or the `aud` claim is missing.
+//
+// NOTE: While the `aud` claim is OPTIONAL is a JWT, the handling of it is
+// application-specific. Since this validation API is helping developers in
+// writing secure application, we decided to REQUIRE the existence of the claim.
+func WithAudience(aud string) ValidatorOption {
+	return func(v *Validator) {
+		v.expectedAud = aud
+	}
+}
+
+// WithIssuer configures the validator to require the specified issuer in the
+// `iss` claim. Validation will fail if a different issuer is specified in the
+// token or the `iss` claim is missing.
+//
+// NOTE: While the `iss` claim is OPTIONAL is a JWT, the handling of it is
+// application-specific. Since this validation API is helping developers in
+// writing secure application, we decided to REQUIRE the existence of the claim.
+func WithIssuer(iss string) ValidatorOption {
+	return func(v *Validator) {
+		v.expectedIss = iss
+	}
+}
+
+// WithSubject configures the validator to require the specified subject in the
+// `sub` claim. Validation will fail if a different subject is specified in the
+// token or the `sub` claim is missing.
+//
+// NOTE: While the `sub` claim is OPTIONAL is a JWT, the handling of it is
+// application-specific. Since this validation API is helping developers in
+// writing secure application, we decided to REQUIRE the existence of the claim.
+func WithSubject(sub string) ValidatorOption {
+	return func(v *Validator) {
+		v.expectedSubPattern = Equals(sub)
+	}
+}
+
+func WithSubjectPattern(pattern PatternFunc) ValidatorOption {
+	return func(v *Validator) {
+		v.expectedSubPattern = pattern
+	}
+}

validator_test.go

@@ -0,0 +1,51 @@
+package jwt
+
+import (
+	"testing"
+	"time"
+)
+
+func TestValidator_Validate(t *testing.T) {
+	type fields struct {
+		leeway             time.Duration
+		timeFunc           func() time.Time
+		verifyIat          bool
+		expectedAud        string
+		expectedIss        string
+		expectedSubPattern PatternFunc
+	}
+	type args struct {
+		claims Claims
+	}
+	tests := []struct {
+		name    string
+		fields  fields
+		args    args
+		wantErr bool
+	}{
+		{
+			name: "with subject pattern",
+			fields: fields{
+				expectedSubPattern: HasPrefix("My"),
+			},
+			args: args{
+				claims: RegisteredClaims{Subject: "MyUser"},
+			},
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			v := &Validator{
+				leeway:             tt.fields.leeway,
+				timeFunc:           tt.fields.timeFunc,
+				verifyIat:          tt.fields.verifyIat,
+				expectedAud:        tt.fields.expectedAud,
+				expectedIss:        tt.fields.expectedIss,
+				expectedSubPattern: tt.fields.expectedSubPattern,
+			}
+			if err := v.Validate(tt.args.claims); (err != nil) != tt.wantErr {
+				t.Errorf("Validator.Validate() error = %v, wantErr %v", err, tt.wantErr)
+			}
+		})
+	}
+}