我从 clojure 和 python 中得到的 hmac 签名略有不同

我从 python 实现和 clojure 实现中获得的 HMAC SHA1 签名略有不同。我很困惑什么会导致这种情况。

Python实现：

import hashlib
import hmac

print hmac.new("my-key", "my-data", hashlib.sha1).hexdigest() # 8bcd5631480093f0b00bd072ead42c032eb31059

Clojure 实现：

(ns my-project.hmac
    (:import (javax.crypto Mac)
         (javax.crypto.spec SecretKeySpec)))

(def algorithm "HmacSHA1")

(defn return-signing-key [key mac]
  "Get an hmac key from the raw key bytes given some 'mac' algorithm.
  Known 'mac' options: HmacSHA1"
    (SecretKeySpec. (.getBytes key) (.getAlgorithm mac)))

(defn sign-to-bytes [key string]
  "Returns the byte signature of a string with a given key, using a SHA1 HMAC."
  (let [mac (Mac/getInstance algorithm)
    secretKey (return-signing-key key mac)]
    (-> (doto mac
      (.init secretKey)
      (.update (.getBytes string)))
    .doFinal)))

; Formatting
(defn bytes-to-hexstring [bytes]
  "Convert bytes to a String."
  (apply str (map #(format "%x" %) bytes)))



; Public functions
(defn sign-to-hexstring [key string]
  "Returns the HMAC SHA1 hex string signature from a key-string pair."
  (bytes-to-hexstring (sign-to-bytes key string)))

(sign-to-hexstring "my-key" "my-data") ; 8bcd563148093f0b0bd072ead42c32eb31059

Clojure 代码中将字节转换为十六进制字符串的部分会删除前导零。

您可以使用保留前导零的格式字符串（"%02x"），或者使用适当的十六进制编码库，例如Guava http://code.google.com/p/guava-libraries/ or 通用编解码器 http://commons.apache.org/proper/commons-codec/.