claims.go

package h256only

import (
	"crypto/subtle"
)

// Structured version of Claims Section, as referenced at
// https://tools.ietf.org/html/rfc7519#section-4.1
// See examples for how to use this with your own claim types
type StandardClaims struct {
	Audience  string `json:"aud,omitempty"`
	ExpiresAt int64  `json:"exp,omitempty"` // Unix timestamp
	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"`
}

// 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(c.Audience, cmp, req)
}

// 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 aud == "" {
		return !required
	}
	if subtle.ConstantTimeCompare([]byte(aud), []byte(cmp)) != 0 {
		return true
	} else {
		return false
	}
}
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
	}
}