Verfahrensweise: Signieren einer Nachricht durch mehrere Signierer
In diesem Beispiel wird eine CMS/PKCS #7-signierte Nachricht unter Verwendung von System.Security.Cryptography.Pkcs erstellt. Die Nachricht wird von mehreren Signierern signiert. Die Signaturen der Nachricht werden anschließend überprüft.
Beispiel
In diesem Beispiel werden die folgenden Klassen verwendet:
Zu Beginn des folgenden Beispiels wird eine zuvor generierte, codierte SignedCms-Nachricht (signiert von einem Signierer mit dem Antragstellernamen "MessageSigner1") verwendet, woraufhin diese ein zweites Mal von einem Signierer mit dem Antragstellernamen "MessageSigner2" signiert wird. Für dieses Beispiel ist es erforderlich, dass der Zertifikatspeicher "My" ein Zertifikat mit öffentlichem Schlüssel mit dem Antragstellernamen "MessageSigner2" enthält und dass diesem ein privater Schlüssel zugeordnet ist.
.gif) Hinweis: |
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Dieses Beispiel dient nur der Veranschaulichung. In Produktionsumgebungen kann ein anderes Modell verwendet werden, in dem Absender und Empfänger der Nachricht in verschiedenen Prozessen mit ihren eindeutigen Anmeldeinformationen des öffentlichen Schlüssels ausgeführt werden. |
Richten Sie dieses Beispiel mithilfe des Dienstprogramms Makecert.exe ein; dies ist nur eine von vielen Möglichkeiten. Certificate Creation Tool (Makecert.exe) ist ein komfortables Dienstprogramm zum Generieren von Testzertifikaten. In einer Produktionsumgebung werden Zertifikate von einer Zertifizierungsstelle generiert.
Mithilfe des folgenden Makecert-Befehls werden die erforderlichen Zertifikate mit öffentlichem Schlüssel und die privaten Schlüssel generiert.
Makecert -n "CN=MessageSigner2" -ss My
// Copyright (c) Microsoft Corporation. All rights reserved.
#region Using directives
using System;
using System.Security.Cryptography.Pkcs;
using System.Security.Cryptography.X509Certificates;
using System.Text;
#endregion
namespace SigningAMessageByMultipleSigners
{
class SignedCmsMultipleSigners
{
// Subject name of the second signer of the message.
const String signerName = "MessageSigner2";
static void Main(string[] args)
{
// An encoded SignedCms message that was generated
// previously. It is the message "The Board of Directors
// hereby adopts the resolution." signed by one signer
// with the subject name "MessageSigner1". This example
// adds a second signature to this encoded
// SignedCms message.
Byte[] signedMessage = {
0x30, 0x82, 0x03, 0x34, 0x06, 0x09, 0x2a, 0x86, 0x48, 0x86,
0xf7, 0x0d, 0x01, 0x07, 0x02, 0xa0, 0x82, 0x03, 0x25, 0x30,
0x82, 0x03, 0x21, 0x02, 0x01, 0x01, 0x31, 0x0b, 0x30, 0x09,
0x06, 0x05, 0x2b, 0x0e, 0x03, 0x02, 0x1a, 0x05, 0x00, 0x30,
0x77, 0x06, 0x09, 0x2a, 0x86, 0x48, 0x86, 0xf7, 0x0d, 0x01,
0x07, 0x01, 0xa0, 0x6a, 0x04, 0x68, 0x54, 0x00, 0x68, 0x00,
0x65, 0x00, 0x20, 0x00, 0x42, 0x00, 0x6f, 0x00, 0x61, 0x00,
0x72, 0x00, 0x64, 0x00, 0x20, 0x00, 0x6f, 0x00, 0x66, 0x00,
0x20, 0x00, 0x44, 0x00, 0x69, 0x00, 0x72, 0x00, 0x65, 0x00,
0x63, 0x00, 0x74, 0x00, 0x6f, 0x00, 0x72, 0x00, 0x73, 0x00,
0x20, 0x00, 0x68, 0x00, 0x65, 0x00, 0x72, 0x00, 0x65, 0x00,
0x62, 0x00, 0x79, 0x00, 0x20, 0x00, 0x61, 0x00, 0x64, 0x00,
0x6f, 0x00, 0x70, 0x00, 0x74, 0x00, 0x73, 0x00, 0x20, 0x00,
0x74, 0x00, 0x68, 0x00, 0x65, 0x00, 0x20, 0x00, 0x72, 0x00,
0x65, 0x00, 0x73, 0x00, 0x6f, 0x00, 0x6c, 0x00, 0x75, 0x00,
0x74, 0x00, 0x69, 0x00, 0x6f, 0x00, 0x6e, 0x00, 0x2e, 0x00,
0xa0, 0x82, 0x01, 0xc2, 0x30, 0x82, 0x01, 0xbe, 0x30, 0x82,
0x01, 0x68, 0xa0, 0x03, 0x02, 0x01, 0x02, 0x02, 0x10, 0x04,
0xd3, 0xc9, 0xdd, 0xb4, 0x38, 0x2a, 0xb5, 0x4d, 0x43, 0x4b,
0x99, 0x65, 0x19, 0xab, 0xeb, 0x30, 0x0d, 0x06, 0x09, 0x2a,
0x86, 0x48, 0x86, 0xf7, 0x0d, 0x01, 0x01, 0x04, 0x05, 0x00,
0x30, 0x16, 0x31, 0x14, 0x30, 0x12, 0x06, 0x03, 0x55, 0x04,
0x03, 0x13, 0x0b, 0x52, 0x6f, 0x6f, 0x74, 0x20, 0x41, 0x67,
0x65, 0x6e, 0x63, 0x79, 0x30, 0x1e, 0x17, 0x0d, 0x30, 0x33,
0x31, 0x32, 0x32, 0x36, 0x32, 0x32, 0x34, 0x35, 0x33, 0x37,
0x5a, 0x17, 0x0d, 0x33, 0x39, 0x31, 0x32, 0x33, 0x31, 0x32,
0x33, 0x35, 0x39, 0x35, 0x39, 0x5a, 0x30, 0x19, 0x31, 0x17,
0x30, 0x15, 0x06, 0x03, 0x55, 0x04, 0x03, 0x13, 0x0e, 0x4d,
0x65, 0x73, 0x73, 0x61, 0x67, 0x65, 0x53, 0x69, 0x67, 0x6e,
0x65, 0x72, 0x31, 0x30, 0x81, 0x9f, 0x30, 0x0d, 0x06, 0x09,
0x2a, 0x86, 0x48, 0x86, 0xf7, 0x0d, 0x01, 0x01, 0x01, 0x05,
0x00, 0x03, 0x81, 0x8d, 0x00, 0x30, 0x81, 0x89, 0x02, 0x81,
0x81, 0x00, 0x9b, 0xb4, 0x92, 0x23, 0x35, 0x3f, 0x23, 0xec,
0x4b, 0xcf, 0x4d, 0x5b, 0xed, 0x81, 0x22, 0x45, 0x62, 0x97,
0xea, 0x38, 0xff, 0x32, 0xc6, 0xa0, 0xdd, 0xeb, 0xd1, 0x18,
0x6a, 0x30, 0xec, 0x6e, 0x4b, 0x4f, 0xab, 0x2a, 0x41, 0xc7,
0x0d, 0xbb, 0xcd, 0x80, 0xdc, 0xef, 0xf2, 0xd0, 0x00, 0xd6,
0x82, 0x81, 0x7f, 0x9a, 0x9c, 0xc9, 0x41, 0xf3, 0xa8, 0x0b,
0xa3, 0x9d, 0xed, 0x9a, 0xee, 0x23, 0xb8, 0xf0, 0xe6, 0x27,
0x65, 0x30, 0x10, 0x13, 0x65, 0x75, 0x33, 0x64, 0x0b, 0x0b,
0xea, 0x7f, 0xf8, 0x3b, 0x49, 0xa7, 0xea, 0xd0, 0x2d, 0xc1,
0xf8, 0xa1, 0x66, 0xb9, 0x6d, 0xa2, 0x8d, 0x36, 0x43, 0x2e,
0xe1, 0x91, 0xe2, 0x41, 0xa1, 0xe6, 0x80, 0xc4, 0xa5, 0xf6,
0x1a, 0xa4, 0x1e, 0x1a, 0x47, 0x3e, 0x5e, 0xf1, 0x97, 0xc9,
0x26, 0x6a, 0x0c, 0xf1, 0x0f, 0xcb, 0x55, 0x03, 0xb2, 0xb7,
0x02, 0x03, 0x01, 0x00, 0x01, 0xa3, 0x4b, 0x30, 0x49, 0x30,
0x47, 0x06, 0x03, 0x55, 0x1d, 0x01, 0x04, 0x40, 0x30, 0x3e,
0x80, 0x10, 0x12, 0xe4, 0x09, 0x2d, 0x06, 0x1d, 0x1d, 0x4f,
0x00, 0x8d, 0x61, 0x21, 0xdc, 0x16, 0x64, 0x63, 0xa1, 0x18,
0x30, 0x16, 0x31, 0x14, 0x30, 0x12, 0x06, 0x03, 0x55, 0x04,
0x03, 0x13, 0x0b, 0x52, 0x6f, 0x6f, 0x74, 0x20, 0x41, 0x67,
0x65, 0x6e, 0x63, 0x79, 0x82, 0x10, 0x06, 0x37, 0x6c, 0x00,
0xaa, 0x00, 0x64, 0x8a, 0x11, 0xcf, 0xb8, 0xd4, 0xaa, 0x5c,
0x35, 0xf4, 0x30, 0x0d, 0x06, 0x09, 0x2a, 0x86, 0x48, 0x86,
0xf7, 0x0d, 0x01, 0x01, 0x04, 0x05, 0x00, 0x03, 0x41, 0x00,
0x1c, 0x97, 0xe5, 0x69, 0xac, 0x34, 0xa5, 0xa0, 0xbb, 0xc5,
0x65, 0x2e, 0xdf, 0x14, 0xa8, 0x8d, 0x4e, 0xf1, 0x86, 0x6c,
0x05, 0x5f, 0x51, 0xf3, 0xcc, 0x09, 0x8e, 0xaa, 0xa9, 0x43,
0x85, 0x11, 0x3b, 0xa9, 0xc3, 0x7d, 0x46, 0x58, 0x6b, 0xae,
0xf5, 0x6b, 0xd4, 0xef, 0xdf, 0xa5, 0x0f, 0xdb, 0x37, 0x78,
0xfd, 0x79, 0xf3, 0x31, 0x61, 0x26, 0x44, 0x98, 0x8b, 0xa4,
0xab, 0x3a, 0x89, 0x6e, 0x31, 0x81, 0xcf, 0x30, 0x81, 0xcc,
0x02, 0x01, 0x01, 0x30, 0x2a, 0x30, 0x16, 0x31, 0x14, 0x30,
0x12, 0x06, 0x03, 0x55, 0x04, 0x03, 0x13, 0x0b, 0x52, 0x6f,
0x6f, 0x74, 0x20, 0x41, 0x67, 0x65, 0x6e, 0x63, 0x79, 0x02,
0x10, 0x04, 0xd3, 0xc9, 0xdd, 0xb4, 0x38, 0x2a, 0xb5, 0x4d,
0x43, 0x4b, 0x99, 0x65, 0x19, 0xab, 0xeb, 0x30, 0x09, 0x06,
0x05, 0x2b, 0x0e, 0x03, 0x02, 0x1a, 0x05, 0x00, 0x30, 0x0d,
0x06, 0x09, 0x2a, 0x86, 0x48, 0x86, 0xf7, 0x0d, 0x01, 0x01,
0x01, 0x05, 0x00, 0x04, 0x81, 0x80, 0x4f, 0x71, 0x32, 0xc8,
0x5f, 0x2f, 0xe3, 0x8e, 0xc7, 0x8d, 0x85, 0x96, 0x28, 0x1d,
0x6e, 0xa6, 0x6e, 0x76, 0x63, 0x64, 0xae, 0x8d, 0xdc, 0x06,
0x64, 0x14, 0xeb, 0xcf, 0xcb, 0x2a, 0xd2, 0x17, 0xaa, 0xa5,
0x24, 0xd9, 0x17, 0x05, 0x07, 0x35, 0x8e, 0xa0, 0xce, 0x48,
0xed, 0x4b, 0x9d, 0xe4, 0x6c, 0xfa, 0xdc, 0x00, 0x82, 0x15,
0x6b, 0xde, 0x29, 0x90, 0x28, 0xe9, 0x53, 0xcb, 0x6b, 0xb7,
0xac, 0xa0, 0xf5, 0xd7, 0x75, 0x92, 0x89, 0x5e, 0x3d, 0x71,
0x46, 0x0c, 0x38, 0xee, 0xfb, 0x51, 0xfc, 0x4b, 0x7e, 0x70,
0x87, 0xde, 0x09, 0x8f, 0x0d, 0x63, 0x27, 0x26, 0x81, 0x43,
0xce, 0xcb, 0x03, 0x44, 0xe9, 0x70, 0xf5, 0xf0, 0x80, 0xcd,
0xe1, 0x89, 0x2b, 0xd8, 0x84, 0xd2, 0xc4, 0x90, 0xef, 0xbc,
0xad, 0x31, 0x2a, 0x3a, 0x29, 0xa0, 0xb0, 0x84, 0x9f, 0x65,
0x5b, 0x0d, 0x6f, 0x61};
Console.WriteLine("System.Security.Cryptography.Pkcs " +
"Sample: Multiple-signer signed " +
"and verified message");
Console.WriteLine("\n\n------------------------------");
Console.WriteLine(" SETUP OF CREDENTIALS ");
Console.WriteLine("------------------------------\n");
// Get the certificate of the additional message signer.
X509Certificate2Collection signerCerts = GetSignerCerts();
Console.WriteLine("\n\n----------------------");
Console.WriteLine(" SENDER SIDE ");
Console.WriteLine("----------------------\n");
// Decode the existing SignedCms message and add a signature
// to it.
byte[] encodedSignedCms = SignMsg(signedMessage, signerCerts);
Console.WriteLine("\n\n------------------------");
Console.WriteLine(" RECIPIENT SIDE ");
Console.WriteLine("------------------------\n");
// Verify all signatures in the message.
if (VerifyMsg(encodedSignedCms))
{
Console.WriteLine("\nMessage verified");
}
else
{
Console.WriteLine("\nMessage failed to verify");
}
}
// Open the My (or Personal) certificate store and search for
// credentials to sign the message with. There must be
// a certificate with subject name "MessageSigner2" in that
// certificate store.
static public X509Certificate2Collection GetSignerCerts()
{
// Open the My certificate store.
X509Store storeMy = new X509Store(StoreName.My,
StoreLocation.CurrentUser);
storeMy.Open(OpenFlags.ReadOnly);
// Display certificates to help troubleshoot
// the example's setup.
Console.WriteLine("Found certs with the following subject " +
"names in the {0} store:", storeMy.Name.ToString());
foreach (X509Certificate2 cert in storeMy.Certificates)
{
Console.WriteLine("\t{0}", cert.SubjectName.Name);
}
// Find the signer's certificate.
// Add to the signers' certificate collection.
X509Certificate2Collection signerCertsColl =
storeMy.Certificates.Find(X509FindType.FindBySubjectName,
signerName, false);
Console.WriteLine(
"Found {0} certificates in the {1} store with name {2}",
signerCertsColl.Count, storeMy.Name, signerName);
// Check to see if the certificate suggested by the example
// requirements is not present.
if (signerCertsColl.Count == 0)
{
Console.WriteLine(
"A suggested certificate to use for this example " +
"is not in the certificate store. Select " +
"an alternate certificate to use for " +
"signing the message.");
}
storeMy.Close();
return signerCertsColl;
}
// Sign the message with the private key of the signer.
static public byte[] SignMsg(
Byte[] signedCmsMsg,
X509Certificate2Collection signerCerts)
{
// Instantiate a SignedCms object, and then decode the
// input encoded SignedCms message.
// Has default SubjectIdentifierType IssuerAndSerialNumber.
// Has default Detached property value false, so message is
// included in the encoded SignedCms.
SignedCms signedCms = new SignedCms();
signedCms.Decode(signedCmsMsg);
DisplaySignedCmsProperties("Original message", signedCms);
// Sign the PKCS #7/CMS message once for each
// signer certificate. In this example, one additional
// signer is added to the SignedCms object.
foreach (X509Certificate2 cert in signerCerts)
{
Console.Write("Computing signature with signer subject "
+ "name {0} ... ", cert.SubjectName.Name);
signedCms.ComputeSignature(new CmsSigner(cert));
Console.WriteLine("Done.");
}
DisplaySignedCmsProperties("Message with additional " +
"signer", signedCms);
// Encode the PKCS #7/CMS message.
return signedCms.Encode();
}
// Verify the encoded SignedCms message and return a Boolean
// value that specifies whether the verification was successful.
static public bool VerifyMsg(byte[] encodedSignedCms)
{
// Prepare an object in which to decode and verify.
SignedCms signedCms = new SignedCms();
signedCms.Decode(encodedSignedCms);
// Catch a verification exception if you want to
// advise the message recipient that security actions might
// be appropriate.
try
{
// Verify signature. Do not validate signer
// certificate chain for the purposes of this example.
// Note that in a production environment, validating
// the signer certificate chain will probably
// be necessary.
Console.Write("Checking signatures on message ... ");
signedCms.CheckSignature(true);
Console.WriteLine("Done.");
}
catch (System.Security.Cryptography.CryptographicException e)
{
Console.WriteLine("VerifyMsg caught exception: {0}",
e.Message);
Console.WriteLine("Verification of the signed PKCS #7 " +
"failed. The message, signatures, or " +
"countersignatures might have been modified " +
"in transit or storage. The message signers or " +
"countersigners might not be who they claim to be. " +
"The message's authenticity or integrity, or both, " +
"are not guaranteed.");
return false;
}
return true;
}
// This method displays some properties of a signed
// CMS/PKCS #7 message. These properties include the number of
// signers and countersigners for each signer, whether the
// message is detached, and the version of the message.
static void DisplaySignedCmsProperties(String info, SignedCms s)
{
Console.WriteLine();
Console.WriteLine("\n>>>>> SignedCms Signer Info: {0}", info);
Console.WriteLine("\tNumber of signers:\t\t\t{0}",
s.SignerInfos.Count);
for (int i = 0; i < s.SignerInfos.Count; i++)
{
Console.WriteLine("\tSubject name of signer #{0}:\t\t{1}",
i + 1, s.SignerInfos[i].Certificate.SubjectName.Name);
Console.WriteLine("\tNumber of countersigners for " +
"signer #{0}:\t{1}",
i + 1, s.SignerInfos[i].CounterSignerInfos.Count);
}
Console.WriteLine("\tMessage detached state:\t\t\t{0}",
s.Detached);
Console.WriteLine("\tMessage version:\t\t\t{0}", s.Version);
Console.WriteLine();
}
}
}
Siehe auch
Aufgaben
Verfahrensweise: Signieren von Nachrichten durch einen Signierer
Verfahrensweise: Gegensignieren einer Nachricht
Verfahrensweise: Versehen einer Nachricht mit einem Umschlag für einen Empfänger
Verfahrensweise: Versehen einer Nachricht mit einem Umschlag für mehrere Empfänger
Konzepte
Verfahrensweise: Signieren und Versehen einer Nachricht mit einem Umschlag
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