我正在尝试使用离线 aadhaar KYC 验证应用程序的给定证书文件来验证数字签名。
该说明在验证文档中给出。
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读取整个 XML 并将 s=”xxxx” 标记从中分离出来。
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使用基于“SHA256withRSA”的哈希和加密技术的签名验证算法
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“s”标签中存在的签名值、剩余的 XML（没有“s”标签）和 UIDAI 公钥（可在此处获取）将被馈送到算法以验证数字签名。
该组织提供的示例 C# 代码片段。 （PS：这也不起作用)
using System;
using System.Security.Cryptography.X509Certificates;
using System.Xml;
namespace test
{
class MainClass
{
public static void Main(string[] args)
{
// link -> https://drive.google.com/file/d/1aSv3HJUFf5_42Z-FqpdVHEk5b3VA3T3D/view
string XMLFilePath = "offlineaadhaar.xml"; //Get the XML file
// link -> https://drive.google.com/file/d/1FW4ciIhZqJuelOcGF2x6VaBCSDO9J-gM/view
string KeyFilePath = "okyc-publickey.cer"; //Get the public key certificate file
XmlDocument ObjXmlDocument = new XmlDocument();
ObjXmlDocument.Load(XMLFilePath); //Load the XML
XmlAttributeCollection SignatureElement = ObjXmlDocument.DocumentElement.Attributes; //Get the all XML attribute
string SignatureValue = SignatureElement.GetNamedItem("s").InnerXml; // Get Signature value
SignatureElement.RemoveNamedItem("s");//Remove the signature "s" attribute from XML and get the new XML to validate
/*----------------Read and parse the public key as string-----------------------*/
X509Certificate2 ObjX509Certificate2 = new X509Certificate2(KeyFilePath, "public"); //Initialize the public ket certificate file
Org.BouncyCastle.X509.X509Certificate objX509Certificate;
Org.BouncyCastle.X509.X509CertificateParser objX509CertificateParser = new Org.BouncyCastle.X509.X509CertificateParser();
objX509Certificate = objX509CertificateParser.ReadCertificate(ObjX509Certificate2.GetRawCertData());
/*----------------End-----------------------*/
/* Init alg */
Org.BouncyCastle.Crypto.ISigner signer = Org.BouncyCastle.Security.SignerUtilities.GetSigner("SHA256withRSA");
/* Populate key */
signer.Init(false, objX509Certificate.GetPublicKey());
/* Get the signature into bytes */
var expectedSig = Convert.FromBase64String(SignatureValue);
/* Get the bytes to be signed from the string */
var msgBytes = System.Text.Encoding.UTF8.GetBytes(ObjXmlDocument.InnerXml);
/* Calculate the signature and see if it matches */
signer.BlockUpdate(msgBytes, 0, msgBytes.Length);
bool Flag = signer.VerifySignature(expectedSig);
if (Flag)
{
Console.WriteLine("XML Validate Successfully");
}
else
{
Console.WriteLine("XML Validation Failed");
}
}
}
}
我正在尝试用 Python 实现，但 XML 验证失败。我不确定证书文件是否错误或者我的代码存在一些错误。
这是我的Python代码：
import xml
import xml.etree.cElementTree as etree
from xml.etree import ElementTree
import OpenSSL
from cryptography import x509
from cryptography.hazmat.backends import default_backend
from Crypto.PublicKey import RSA
from base64 import b64encode, b64decode
from M2Crypto import BIO, RSA, EVP
xmlDoc = open('adhar.xml', 'r').read()
Tr = etree.XML(xmlDoc)
Tr.keys()
# ['s', 'r', 'a', 'g', 'm', 'e', 'd', 'i', 'n', 'v']
sign = Tr.get('s')
len(sign)
# 344
del Tr.attrib['s']
from M2Crypto import X509
x509 =X509.load_cert('ekyc_public_key.cer')
#x509 =X509.load_cert(cert4)
rsa = x509.get_pubkey().get_rsa()
pubkey = EVP.PKey()
pubkey.assign_rsa(rsa)
xmlstr = etree.tostring(Tr, encoding='utf8', method='xml')
#rstr=str(xmlstr)[45:][:-1]
#rstr = rstr.encode(encoding='utf-8')
# if you need a different digest than the default 'sha1':
pubkey.reset_context(md='sha256')
pubkey.verify_init()
# hashlib.sha256(message_without_sign).digest()
pubkey.verify_update(xmlstr)
if(pubkey.verify_final(b64decode(sign)) != 1):
print('Digital Signeture not validated')
else:
print('Digital Signeture validated')
