[chore]: Bump github.com/SherClockHolmes/webpush-go from 1.3.0 to 1.4.0 (#3694)

Bumps [github.com/SherClockHolmes/webpush-go](https://github.com/SherClockHolmes/webpush-go) from 1.3.0 to 1.4.0.
- [Release notes](https://github.com/SherClockHolmes/webpush-go/releases)
- [Commits](https://github.com/SherClockHolmes/webpush-go/compare/v1.3.0...v1.4.0)

---
updated-dependencies:
- dependency-name: github.com/SherClockHolmes/webpush-go
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

vendor/github.com/golang-jwt/jwt/v5/validator.go

@@ -0,0 +1,316 @@
+package jwt
+
+import (
+	"crypto/subtle"
+	"fmt"
+	"time"
+)
+
+// ClaimsValidator is an interface that can be implemented by custom claims who
+// wish to execute any additional claims validation based on
+// application-specific logic. The Validate function is then executed in
+// addition to the regular claims validation and any error returned is appended
+// to the final validation result.
+//
+//	type MyCustomClaims struct {
+//	    Foo string `json:"foo"`
+//	    jwt.RegisteredClaims
+//	}
+//
+//	func (m MyCustomClaims) Validate() error {
+//	    if m.Foo != "bar" {
+//	        return errors.New("must be foobar")
+//	    }
+//	    return nil
+//	}
+type ClaimsValidator interface {
+	Claims
+	Validate() error
+}
+
+// Validator is the core of the new Validation API. It is automatically used by
+// a [Parser] during parsing and can be modified with various parser options.
+//
+// The [NewValidator] function should be used to create an instance of this
+// struct.
+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
+
+	// requireExp specifies whether the exp claim is required
+	requireExp bool
+
+	// 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
+
+	// expectedSub contains the subject this token expects. Supplying an empty
+	// string will disable sub checking.
+	expectedSub string
+}
+
+// NewValidator can be used to create a stand-alone validator with the supplied
+// options. This validator can then be used to validate already parsed claims.
+//
+// Note: Under normal circumstances, explicitly creating a validator is not
+// needed and can potentially be dangerous; instead functions of the [Parser]
+// class should be used.
+//
+// The [Validator] is only checking the *validity* of the claims, such as its
+// expiration time, but it does NOT perform *signature verification* of the
+// token.
+func NewValidator(opts ...ParserOption) *Validator {
+	p := NewParser(opts...)
+	return p.validator
+}
+
+// Validate validates the given claims. It will also perform any custom
+// validation if claims implements the [ClaimsValidator] interface.
+//
+// Note: It will NOT perform any *signature verification* on the token that
+// contains the claims and expects that the [Claim] was already successfully
+// verified.
+func (v *Validator) Validate(claims Claims) error {
+	var (
+		now  time.Time
+		errs []error = make([]error, 0, 6)
+		err  error
+	)
+
+	// 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 usage of the claim
+	// itself is OPTIONAL by default. requireExp overrides this behavior
+	// and makes the exp claim mandatory.
+	if err = v.verifyExpiresAt(claims, now, v.requireExp); err != nil {
+		errs = append(errs, err)
+	}
+
+	// We always need to check not-before, but usage of the claim itself is
+	// OPTIONAL.
+	if err = v.verifyNotBefore(claims, now, false); err != nil {
+		errs = append(errs, err)
+	}
+
+	// Check issued-at if the option is enabled
+	if v.verifyIat {
+		if err = v.verifyIssuedAt(claims, now, false); err != nil {
+			errs = append(errs, err)
+		}
+	}
+
+	// If we have an expected audience, we also require the audience claim
+	if v.expectedAud != "" {
+		if err = v.verifyAudience(claims, v.expectedAud, true); err != nil {
+			errs = append(errs, err)
+		}
+	}
+
+	// If we have an expected issuer, we also require the issuer claim
+	if v.expectedIss != "" {
+		if err = v.verifyIssuer(claims, v.expectedIss, true); err != nil {
+			errs = append(errs, err)
+		}
+	}
+
+	// If we have an expected subject, we also require the subject claim
+	if v.expectedSub != "" {
+		if err = v.verifySubject(claims, v.expectedSub, true); err != nil {
+			errs = append(errs, err)
+		}
+	}
+
+	// Finally, we want to give the claim itself some possibility to do some
+	// additional custom validation based on a custom Validate function.
+	cvt, ok := claims.(ClaimsValidator)
+	if ok {
+		if err := cvt.Validate(); err != nil {
+			errs = append(errs, err)
+		}
+	}
+
+	if len(errs) == 0 {
+		return nil
+	}
+
+	return joinErrors(errs...)
+}
+
+// verifyExpiresAt compares the exp claim in claims against cmp. This function
+// will succeed if cmp < exp. Additional leeway is taken into account.
+//
+// If exp is not set, it will succeed if the claim is not required,
+// otherwise ErrTokenRequiredClaimMissing will be returned.
+//
+// Additionally, if any error occurs while retrieving the claim, e.g., when its
+// the wrong type, an ErrTokenUnverifiable error will be returned.
+func (v *Validator) verifyExpiresAt(claims Claims, cmp time.Time, required bool) error {
+	exp, err := claims.GetExpirationTime()
+	if err != nil {
+		return err
+	}
+
+	if exp == nil {
+		return errorIfRequired(required, "exp")
+	}
+
+	return errorIfFalse(cmp.Before((exp.Time).Add(+v.leeway)), ErrTokenExpired)
+}
+
+// verifyIssuedAt compares the iat claim in claims against cmp. This function
+// will succeed if cmp >= iat. Additional leeway is taken into account.
+//
+// If iat is not set, it will succeed if the claim is not required,
+// otherwise ErrTokenRequiredClaimMissing will be returned.
+//
+// Additionally, if any error occurs while retrieving the claim, e.g., when its
+// the wrong type, an ErrTokenUnverifiable error will be returned.
+func (v *Validator) verifyIssuedAt(claims Claims, cmp time.Time, required bool) error {
+	iat, err := claims.GetIssuedAt()
+	if err != nil {
+		return err
+	}
+
+	if iat == nil {
+		return errorIfRequired(required, "iat")
+	}
+
+	return errorIfFalse(!cmp.Before(iat.Add(-v.leeway)), ErrTokenUsedBeforeIssued)
+}
+
+// verifyNotBefore compares the nbf claim in claims against cmp. This function
+// will return true if cmp >= nbf. Additional leeway is taken into account.
+//
+// If nbf is not set, it will succeed if the claim is not required,
+// otherwise ErrTokenRequiredClaimMissing will be returned.
+//
+// Additionally, if any error occurs while retrieving the claim, e.g., when its
+// the wrong type, an ErrTokenUnverifiable error will be returned.
+func (v *Validator) verifyNotBefore(claims Claims, cmp time.Time, required bool) error {
+	nbf, err := claims.GetNotBefore()
+	if err != nil {
+		return err
+	}
+
+	if nbf == nil {
+		return errorIfRequired(required, "nbf")
+	}
+
+	return errorIfFalse(!cmp.Before(nbf.Add(-v.leeway)), ErrTokenNotValidYet)
+}
+
+// verifyAudience compares the aud claim against cmp.
+//
+// If aud is not set or an empty list, it will succeed if the claim is not required,
+// otherwise ErrTokenRequiredClaimMissing will be returned.
+//
+// Additionally, if any error occurs while retrieving the claim, e.g., when its
+// the wrong type, an ErrTokenUnverifiable error will be returned.
+func (v *Validator) verifyAudience(claims Claims, cmp string, required bool) error {
+	aud, err := claims.GetAudience()
+	if err != nil {
+		return err
+	}
+
+	if len(aud) == 0 {
+		return errorIfRequired(required, "aud")
+	}
+
+	// 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 errorIfRequired(required, "aud")
+	}
+
+	return errorIfFalse(result, ErrTokenInvalidAudience)
+}
+
+// verifyIssuer compares the iss claim in claims against cmp.
+//
+// If iss is not set, it will succeed if the claim is not required,
+// otherwise ErrTokenRequiredClaimMissing will be returned.
+//
+// Additionally, if any error occurs while retrieving the claim, e.g., when its
+// the wrong type, an ErrTokenUnverifiable error will be returned.
+func (v *Validator) verifyIssuer(claims Claims, cmp string, required bool) error {
+	iss, err := claims.GetIssuer()
+	if err != nil {
+		return err
+	}
+
+	if iss == "" {
+		return errorIfRequired(required, "iss")
+	}
+
+	return errorIfFalse(iss == cmp, ErrTokenInvalidIssuer)
+}
+
+// verifySubject compares the sub claim against cmp.
+//
+// If sub is not set, it will succeed if the claim is not required,
+// otherwise ErrTokenRequiredClaimMissing will be returned.
+//
+// Additionally, if any error occurs while retrieving the claim, e.g., when its
+// the wrong type, an ErrTokenUnverifiable error will be returned.
+func (v *Validator) verifySubject(claims Claims, cmp string, required bool) error {
+	sub, err := claims.GetSubject()
+	if err != nil {
+		return err
+	}
+
+	if sub == "" {
+		return errorIfRequired(required, "sub")
+	}
+
+	return errorIfFalse(sub == cmp, ErrTokenInvalidSubject)
+}
+
+// errorIfFalse returns the error specified in err, if the value is true.
+// Otherwise, nil is returned.
+func errorIfFalse(value bool, err error) error {
+	if value {
+		return nil
+	} else {
+		return err
+	}
+}
+
+// errorIfRequired returns an ErrTokenRequiredClaimMissing error if required is
+// true. Otherwise, nil is returned.
+func errorIfRequired(required bool, claim string) error {
+	if required {
+		return newError(fmt.Sprintf("%s claim is required", claim), ErrTokenRequiredClaimMissing)
+	} else {
+		return nil
+	}
+}