Next.js 15 JWT RS256 签名验证与 Cookie 会话治理实践

核心价值在 Edge 环境通过 `crypto.subtle` 验证 RS256 签名，避免引入重型依赖。对 `exp/aud/iss` 进行严格校验并与 Cookie 会话结合，提升安全性与一致性。验证实现export const runtime = 'edge'

const JWK: JsonWebKey = { kty: 'RSA', n: 'BASE64URL_N', e: 'AQAB' }

const AUD = 'web'

const ISS = 'https://auth.example.com'

function b64urlToBytes(s: string) {

s = s.replace(/-/g, '+').replace(/_/g, '/')

const pad = s.length % 4 === 0 ? '' : '='.repeat(4 - (s.length % 4))

const raw = atob(s + pad)

const buf = new Uint8Array(raw.length)

for (let i = 0; i < raw.length; i++) buf[i] = raw.charCodeAt(i)

return buf

}

async function verifyRS256(jwt: string) {

const [h, p, s] = jwt.split('.')

if (!h || !p || !s) return null

const data = new TextEncoder().encode(`${h}.${p}`)

const sig = b64urlToBytes(s)

const key = await crypto.subtle.importKey('jwk', JWK, { name: 'RSASSA-PKCS1-v1_5', hash: 'SHA-256' }, false, ['verify'])

const ok = await crypto.subtle.verify('RSASSA-PKCS1-v1_5', key, sig, data)

if (!ok) return null

const payload = JSON.parse(new TextDecoder().decode(b64urlToBytes(p)))

return payload

}

export async function GET(req: Request) {

const auth = req.headers.get('authorization') || ''

const token = auth.startsWith('Bearer ') ? auth.slice(7) : ''

const payload = token ? await verifyRS256(token) : null

if (!payload) return new Response('Unauthorized', { status: 401 })

const now = Math.floor(Date.now() / 1000)

if (payload.exp && now >= payload.exp) return new Response('Expired', { status: 401 })

if (payload.aud !== AUD || payload.iss !== ISS) return new Response('Unauthorized', { status: 401 })

const sid = crypto.randomUUID()

return Response.json({ ok: true, sub: payload.sub }, {

headers: {

'Set-Cookie': `sid=${sid}; Path=/; HttpOnly; SameSite=Lax`,

'Cache-Control': 'no-store',

},

})

}

治理建议使用 JWK 公钥验证 RS256，私钥只在身份提供方；对 `kid` 做密钥轮换管理。会话 Cookie 设置 `HttpOnly/SameSite`，必要时 `Secure`；与 CSRF 防护协同。结论在 Edge 路由中以原生 Web Crypto 验证 JWT 并结合 Cookie 会话治理，具备高性能与低依赖的优势，适合现代前端架构的安全入口。