crypto.timingSafeEqual(a, b)

• a <ArrayBuffer> | <Buffer> | <TypedArray> | <DataView>
• b <ArrayBuffer> | <Buffer> | <TypedArray> | <DataView>
• 返回: <boolean>

此函数使用恒定时间算法比较表示给定 ArrayBuffer、TypedArray 或 DataView 实例的底层字节。

此函数不会泄露允许攻击者猜测其中一个值的计时信息。 这适用于比较 HMAC 摘要或秘密值，如身份验证 cookie 或功能网址。

a 和 b 必须都是 Buffer、TypedArrays 或 DataView，并且它们的字节长度必须相同。 如果 a 和 b 的字节长度不同，则抛出错误。

如果 a 和 b 中的至少一个是每个条目超过一个字节的 TypedArray，例如 Uint16Array，则将使用平台字节顺序计算结果。

当两个输入都是 Float32Array 或 Float64Array 时，由于浮点数的 IEEE 754 编码，此函数可能会返回意外结果。 特别是，x === y 和 Object.is(x, y) 都不意味着两个浮点数 x 和 y 的字节表示是相等的。

使用 crypto.timingSafeEqual 并不能保证周围的代码是时间安全的。 应注意确保周围的代码不会引入时序漏洞。

• a <ArrayBuffer> | <Buffer> | <TypedArray> | <DataView>
• b <ArrayBuffer> | <Buffer> | <TypedArray> | <DataView>
• Returns: <boolean>

This function compares the underlying bytes that represent the given ArrayBuffer, TypedArray, or DataView instances using a constant-time algorithm.

This function does not leak timing information that would allow an attacker to guess one of the values. This is suitable for comparing HMAC digests or secret values like authentication cookies or capability urls.

a and b must both be Buffers, TypedArrays, or DataViews, and they must have the same byte length. An error is thrown if a and b have different byte lengths.

If at least one of a and b is a TypedArray with more than one byte per entry, such as Uint16Array, the result will be computed using the platform byte order.

When both of the inputs are Float32Arrays or Float64Arrays, this function might return unexpected results due to IEEE 754 encoding of floating-point numbers. In particular, neither x === y nor Object.is(x, y) implies that the byte representations of two floating-point numbers x and y are equal.

Use of crypto.timingSafeEqual does not guarantee that the surrounding code is timing-safe. Care should be taken to ensure that the surrounding code does not introduce timing vulnerabilities.