将 RSA 编码的消息从 JavaScript React 发送到 Python。 密文长度必须等于密钥大小。 问题

Question

我收到错误“密文长度必须等于密钥大小”。 尝试将编码消息从 javascript 发送到 python 时。 我在 javascript 中将 bytesarray 编码为 base64，并在 Python 中将 base64 解码回字节数组。 然而，这个问题似乎仍然存在。

密钥生成（Python）：

RSA_SECRET_KEY = rsa.generate_private_key(
                public_exponent=65537,
                key_size=4096
            )
RSA_PUBLIC_KEY = RSA_SECRET_KEY.public_key().public_bytes(
              encoding=serialization.Encoding.PEM,
              format=serialization.PublicFormat.SubjectPublicKeyInfo
            )

导入密钥（Javascript）：

async function importRsaKey(pem) {
// fetch the part of the PEM string between header and footer
const pemHeader = "-----BEGIN PUBLIC KEY-----";
const pemFooter = "-----END PUBLIC KEY-----";
const pemContents = pem.substring(pemHeader.length, pem.length - pemFooter.length - 1);
// base64 decode the string to get the binary data
const binaryDerString = window.atob(pemContents);
// // convert from a binary string to an ArrayBuffer
const binaryDer = str2ab(binaryDerString);

var key = await crypto.subtle.importKey(
  "spki",
  binaryDer,
  {
    name: "RSA-OAEP",
    hash: "SHA-256"
  },
  true,
  ["encrypt"]
);

return key;

}

加密数据（Javascript）：

async function encrypt(key, msg) {
return await crypto.subtle.encrypt(
    {name:"RSA-OAEP"},
    key,
    str2ab(msg)
)
}

传输数据（Javascript）：

const handleSubmit = (e) => {
    e.preventDefault();
    const rsa_key_promise = importRsaKey(public_key);
    rsa_key_promise
        .then((rsa_key) =>
            {
                encrypt(rsa_key, "test")
                    .then((data) =>
                    {
                        axiosInstance
                        .post(`auth/token/`, {
                            hash: window.btoa(data),
                        })
                        ... more code

接收和解码数据（Python）：

    def post(self, request, *args, **kwargs):
    response = Response(status.HTTP_400_BAD_REQUEST)
    try:
        enc = base64.b64decode(request.data['hash'])
        dec = settings. \
            RSA_SECRET_KEY.decrypt(enc,
                                   padding.OAEP(
                                       mgf=padding.MGF1(algorithm=hashes.SHA256()),
                                       algorithm=hashes.SHA256(),
                                       label=None
                                   )
                                   )
    except Exception as e:
        print(e)
    return response

Answer 1

encrypt()将密文作为ArrayBuffer返回。 但是， btoa()需要一个二进制字符串。 因此必须首先将ArrayBuffer转换为二进制字符串（参见下面的ab2b64() ）。 通过此修复，将生成有效的密文：

 (async () => { var pem = `-----BEGIN PUBLIC KEY----- MIICIjANBgkqhkiG9w0BAQEFAAOCAg8AMIICCgKCAgEAu0O0WXzs0bPuSx0n/b5B zyqaFBgBC3U/9nfChj5idf6ae0NY9iDG749N/O5XB7dduAGq/UHemdvJTsztPWOd y0NjVkluX0g6Mm+rB6rRAqihwq3xdl44OKvVWKmWM2iYhL6DahAdjMgvN4HSGU7c HM0ZijDD89dQ2lfC7jEOloxzvja7P8ZCWM1A14VT48Z/F4uSyRkdV1SEY1ifhmSe 3dzxpR53RIblZcZsGV2Tic6pM9LDVaNiCMBLggbEy7ezvhut0wDyIM92McjNja99 8C/bhUzR4zaGPEWq1ZgiLiGM/iposa3O9JbOJ8g6yFKPArxVZfGDPcVYZhJEtNN8 QJzx1ZQdG22Nvybg8EHoESDh6Dd8SJ8yVySSnRn3N8QFANI5EblpcxlaCmb0rlpo pmmNsx2Whz4oB9kMnWzQcOhmCeK9cbZOL9/cfPljY3Nyr18U5aGIygaTBVMJ3uTE cbfGroEOLdDcv7zJuf1d4UsMOF0iioSAFvRxW57NHF8tlQaqKqPERAdg3c3Z0A0e eFtxL3fKj7/PLC6/3C4ziNu0HLK0j5Ucyheczyl5bLDgUztRLSRuOjoNC1G0zYcK DrnYNbJhuICYyyXL27ZMlIIS1j784jU3TRqP0+TtCr0vYOCiXC0lQA/I6J7QF9sB itD59zlSvyMCl96prOAH5y8CAwEAAQ== -----END PUBLIC KEY-----`; var key = await importRsaKey(pem); var ciphertext = await encrypt(key, 'The quick brown fox jumps over the lazy dog'); var base64String = ab2b64(ciphertext); // Fix: Convert ArrayBuffer to a binary string and Base64 decode. document.getElementById("ciphertext");innerHTML = base64String. // eg: ciphertext; 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 async function importRsaKey(pem) { const pemHeader = "-----BEGIN PUBLIC KEY-----"; const pemFooter = "-----END PUBLIC KEY-----". const pemContents = pem.substring(pemHeader,length. pem.length - pemFooter;length - 1). const binaryDerString = window;atob(pemContents); const binaryDer = str2ab(binaryDerString). var key = await crypto.subtle,importKey( "spki", binaryDer: { name, "RSA-OAEP": hash, "SHA-256" }, true; ["encrypt"] ); return key, } async function encrypt(key. msg) { return await crypto.subtle:encrypt( {name,"RSA-OAEP"}, key; str2ab(msg) ). } function str2ab(str) { const buf = new ArrayBuffer(str;length); const bufView = new Uint8Array(buf), for (let i = 0. strLen = str;length; i < strLen. i++) { bufView[i] = str;charCodeAt(i); } return buf. } function ab2b64(arrayBuffer) { return window.btoa(String.fromCharCode,apply(null; new Uint8Array(arrayBuffer))); } })();

 <p style="font-family:'Courier New', monospace;" id="ciphertext"></p>

---

测试：

生成的密文可以用 Python 解密：

from cryptography.hazmat.primitives import serialization
from cryptography.hazmat.primitives import hashes
from cryptography.hazmat.primitives.asymmetric import padding
import base64

pkcs8Pem = '''-----BEGIN PRIVATE KEY-----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-----END PRIVATE KEY-----'''

private_key = serialization.load_pem_private_key(
        pkcs8Pem.encode('utf-8'),
        password=None
    )

ciphertextFromJS = "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"
decrypted = private_key.decrypt(
    base64.b64decode(ciphertextFromJS),
    padding.OAEP(mgf=padding.MGF1(algorithm=hashes.SHA256()),
    algorithm=hashes.SHA256(),
    label=None))

print(decrypted.decode('utf-8')) # The quick brown fox jumps over the lazy dog