golang-jwt/jwt

事实及其依据的检查

以下内容均非抄自文档。检查脚本 content/libraries/verify/golang-jwt/run.sh 于2026年10月20日在容器镜像 golang:1.27.3-trixie 中运行了 golang-jwt/jwt 5.3.1；本页内容必须与它的输出一致，每条事实都列出了对应的输出行。

• JWS 算法

  HS256HS384HS512RS256RS384RS512PS256PS384PS512ES256ES384ES512EdDSA

  256/384/512 位的 HS、RS、PS 和 ES 以及 EdDSA 的签名与验证均成功；ES256K、Ed25519 和 Ed448 没有注册的签名方法。

  检查记录

  fact jws-algorithms = HS256, HS384, HS512, RS256, RS384, RS512, PS256, PS384, PS512, ES256, ES384, ES512, EdDSA
  evidence jws-algorithms: ES256K: no signing method registered
  evidence jws-algorithms: Ed25519: no signing method registered
  evidence jws-algorithms: Ed448: no signing method registered

• ES256 签名编码

  raw

  ES256 签名是 64 字节的原始 r‖s。

  检查记录

  fact jws-ecdsa-encoding = raw

• JWS 中的 DER 签名

  rejected

  DER 编码的 ES256 签名会报错 token signature is invalid: crypto/ecdsa: verification error。

  检查记录

  fact jws-der-signature = rejected
  evidence jws-der-signature: token signature is invalid: crypto/ecdsa: verification error

• 算法允许列表

  from-key

  不使用 WithValidMethods 时，由密钥的 Go 类型决定：用返回 EC 密钥的 keyfunc 验证 RS256 令牌，报错 key is of invalid type: RSA verify expects *rsa.PublicKey。

  检查记录

  fact jwt-algorithm-allowlist = from-key
  evidence jwt-algorithm-allowlist: RS256 token, keyfunc returning the EC public key, no WithValidMethods: token signature is invalid: key is of invalid type: RSA verify expects *rsa.PublicKey

• 未签名的令牌（alg none）

  opt-in

  除非 keyfunc 返回 jwt.UnsafeAllowNoneSignatureType，否则未签名的令牌会报错 'none' signature type is not allowed。

  检查记录

  fact jwt-alg-none = opt-in
  evidence jwt-alg-none: with the EC key: token signature is invalid: token is unverifiable: 'none' signature type is not allowed
  evidence jwt-alg-none: keyfunc returning jwt.UnsafeAllowNoneSignatureType: <nil>

• 把公钥用作 HMAC 密钥

  rejected

  以 PEM 文本为密钥的 HS256 令牌，用返回 *ecdsa.PublicKey 的 keyfunc 验证失败（HMAC verify expects []byte），但当 keyfunc 返回 PEM 字节时验证通过。

  检查记录

  fact jwt-hmac-public-key = rejected
  evidence jwt-hmac-public-key: keyfunc returning *ecdsa.PublicKey: token signature is invalid: key is of invalid type: HMAC verify expects []byte
  evidence jwt-hmac-public-key: keyfunc returning the PEM bytes (a keyfunc that loads keys as bytes): <nil>

• 按 alg 检查曲线

  enforced

  用 P-384 密钥签名 ES256 时报错 key is invalid。

  检查记录

  fact jwt-ecdsa-curve-check = enforced
  evidence jwt-ecdsa-curve-check: key is invalid

• 默认时钟偏差

  0s

  默认没有容差：三秒前过期的令牌被拒绝。

  检查记录

  fact jwt-clock-skew = 0s

• 是否要求过期时间声明

  no

  不含 exp 的令牌被视为有效；使用 WithExpirationRequired() 后，它会报错 token is missing required claim: exp claim is required。

  检查记录

  fact jwt-exp-required = no
  evidence jwt-exp-required: with WithExpirationRequired: token has invalid claims: token is missing required claim: exp claim is required

用法

package main

import (
	"crypto/ecdsa"
	"crypto/elliptic"
	"crypto/rand"
	"fmt"
	"time"

	"github.com/golang-jwt/jwt/v5"
)

func main() {
	key, _ := ecdsa.GenerateKey(elliptic.P256(), rand.Reader)
	claims := jwt.RegisteredClaims{Subject: "user-42", Issuer: "https://auth.example.com", ExpiresAt: jwt.NewNumericDate(time.Now().Add(10 * time.Minute))}
	signed, _ := jwt.NewWithClaims(jwt.SigningMethodES256, claims).SignedString(key)

	// The keyfunc returns a typed key; the options pin the method and the claims.
	token, err := jwt.ParseWithClaims(signed, &jwt.RegisteredClaims{},
		func(*jwt.Token) (any, error) { return &key.PublicKey, nil },
		jwt.WithValidMethods([]string{"ES256"}),
		jwt.WithIssuer("https://auth.example.com"),
		jwt.WithExpirationRequired(),
		jwt.WithLeeway(30*time.Second),
	)
	fmt.Println("valid:", err == nil && token.Valid, "sub:", token.Claims.(*jwt.RegisteredClaims).Subject)
}