410 lines
12 KiB
C#
410 lines
12 KiB
C#
//
|
|
// X509CRL.cs: Handles X.509 certificates revocation lists.
|
|
//
|
|
// Author:
|
|
// Sebastien Pouliot <sebastien@xamarin.com>
|
|
//
|
|
// Copyright (C) 2004,2006 Novell Inc. (http://www.novell.com)
|
|
// Copyright 2013 Xamarin Inc. (http://www.xamarin.com)
|
|
//
|
|
// Permission is hereby granted, free of charge, to any person obtaining
|
|
// a copy of this software and associated documentation files (the
|
|
// "Software"), to deal in the Software without restriction, including
|
|
// without limitation the rights to use, copy, modify, merge, publish,
|
|
// distribute, sublicense, and/or sell copies of the Software, and to
|
|
// permit persons to whom the Software is furnished to do so, subject to
|
|
// the following conditions:
|
|
//
|
|
// The above copyright notice and this permission notice shall be
|
|
// included in all copies or substantial portions of the Software.
|
|
//
|
|
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
|
|
// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
|
|
// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
|
|
// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
|
|
// LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
|
|
// OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
|
|
// WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
|
|
//
|
|
|
|
using System;
|
|
using System.Collections;
|
|
using System.Globalization;
|
|
using System.IO;
|
|
using System.Security.Cryptography;
|
|
|
|
using Mono.Security.Cryptography;
|
|
using Mono.Security.X509.Extensions;
|
|
|
|
namespace Mono.Security.X509 {
|
|
/*
|
|
* CertificateList ::= SEQUENCE {
|
|
* tbsCertList TBSCertList,
|
|
* signatureAlgorithm AlgorithmIdentifier,
|
|
* signature BIT STRING
|
|
* }
|
|
*
|
|
* TBSCertList ::= SEQUENCE {
|
|
* version Version OPTIONAL,
|
|
* -- if present, MUST be v2
|
|
* signature AlgorithmIdentifier,
|
|
* issuer Name,
|
|
* thisUpdate Time,
|
|
* nextUpdate Time OPTIONAL,
|
|
* revokedCertificates SEQUENCE OF SEQUENCE {
|
|
* userCertificate CertificateSerialNumber,
|
|
* revocationDate Time,
|
|
* crlEntryExtensions Extensions OPTIONAL
|
|
* -- if present, MUST be v2
|
|
* } OPTIONAL,
|
|
* crlExtensions [0] Extensions OPTIONAL }
|
|
* -- if present, MUST be v2
|
|
*/
|
|
#if !INSIDE_CORLIB
|
|
public
|
|
#endif
|
|
class X509Crl {
|
|
|
|
public class X509CrlEntry {
|
|
|
|
private byte[] sn;
|
|
private DateTime revocationDate;
|
|
private X509ExtensionCollection extensions;
|
|
|
|
internal X509CrlEntry (byte[] serialNumber, DateTime revocationDate, X509ExtensionCollection extensions)
|
|
{
|
|
sn = serialNumber;
|
|
this.revocationDate = revocationDate;
|
|
if (extensions == null)
|
|
this.extensions = new X509ExtensionCollection ();
|
|
else
|
|
this.extensions = extensions;
|
|
}
|
|
|
|
internal X509CrlEntry (ASN1 entry)
|
|
{
|
|
sn = entry [0].Value;
|
|
Array.Reverse (sn);
|
|
revocationDate = ASN1Convert.ToDateTime (entry [1]);
|
|
extensions = new X509ExtensionCollection (entry [2]);
|
|
}
|
|
|
|
public byte[] SerialNumber {
|
|
get { return (byte[]) sn.Clone (); }
|
|
}
|
|
|
|
public DateTime RevocationDate {
|
|
get { return revocationDate; }
|
|
}
|
|
|
|
public X509ExtensionCollection Extensions {
|
|
get { return extensions; }
|
|
}
|
|
|
|
public byte[] GetBytes ()
|
|
{
|
|
ASN1 sequence = new ASN1 (0x30);
|
|
sequence.Add (new ASN1 (0x02, sn));
|
|
sequence.Add (ASN1Convert.FromDateTime (revocationDate));
|
|
if (extensions.Count > 0)
|
|
sequence.Add (new ASN1 (extensions.GetBytes ()));
|
|
return sequence.GetBytes ();
|
|
}
|
|
}
|
|
|
|
private string issuer;
|
|
private byte version;
|
|
private DateTime thisUpdate;
|
|
private DateTime nextUpdate;
|
|
private ArrayList entries;
|
|
private string signatureOID;
|
|
private byte[] signature;
|
|
private X509ExtensionCollection extensions;
|
|
private byte[] encoded;
|
|
private byte[] hash_value;
|
|
|
|
public X509Crl (byte[] crl)
|
|
{
|
|
if (crl == null)
|
|
throw new ArgumentNullException ("crl");
|
|
encoded = (byte[]) crl.Clone ();
|
|
Parse (encoded);
|
|
}
|
|
|
|
private void Parse (byte[] crl)
|
|
{
|
|
string e = "Input data cannot be coded as a valid CRL.";
|
|
try {
|
|
// CertificateList ::= SEQUENCE {
|
|
ASN1 encodedCRL = new ASN1 (encoded);
|
|
if ((encodedCRL.Tag != 0x30) || (encodedCRL.Count != 3))
|
|
throw new CryptographicException (e);
|
|
|
|
// CertificateList / TBSCertList,
|
|
ASN1 toBeSigned = encodedCRL [0];
|
|
if ((toBeSigned.Tag != 0x30) || (toBeSigned.Count < 3))
|
|
throw new CryptographicException (e);
|
|
|
|
int n = 0;
|
|
// CertificateList / TBSCertList / Version OPTIONAL, -- if present, MUST be v2
|
|
if (toBeSigned [n].Tag == 0x02) {
|
|
version = (byte) (toBeSigned [n++].Value [0] + 1);
|
|
}
|
|
else
|
|
version = 1; // DEFAULT
|
|
// CertificateList / TBSCertList / AlgorithmIdentifier,
|
|
signatureOID = ASN1Convert.ToOid (toBeSigned [n++][0]);
|
|
// CertificateList / TBSCertList / Name,
|
|
issuer = X501.ToString (toBeSigned [n++]);
|
|
// CertificateList / TBSCertList / Time,
|
|
thisUpdate = ASN1Convert.ToDateTime (toBeSigned [n++]);
|
|
// CertificateList / TBSCertList / Time OPTIONAL,
|
|
ASN1 next = toBeSigned [n++];
|
|
if ((next.Tag == 0x17) || (next.Tag == 0x18)) {
|
|
nextUpdate = ASN1Convert.ToDateTime (next);
|
|
next = toBeSigned [n++];
|
|
}
|
|
// CertificateList / TBSCertList / revokedCertificates SEQUENCE OF SEQUENCE {
|
|
entries = new ArrayList ();
|
|
// this is OPTIONAL so it may not be present if no entries exists
|
|
if ((next != null) && (next.Tag == 0x30)) {
|
|
ASN1 revokedCertificates = next;
|
|
for (int i=0; i < revokedCertificates.Count; i++) {
|
|
entries.Add (new X509CrlEntry (revokedCertificates [i]));
|
|
}
|
|
} else {
|
|
n--;
|
|
}
|
|
// CertificateList / TBSCertList / crlExtensions [0] Extensions OPTIONAL }
|
|
ASN1 extns = toBeSigned [n];
|
|
if ((extns != null) && (extns.Tag == 0xA0) && (extns.Count == 1))
|
|
extensions = new X509ExtensionCollection (extns [0]);
|
|
else
|
|
extensions = new X509ExtensionCollection (null); // result in a read only object
|
|
// CertificateList / AlgorithmIdentifier
|
|
string signatureAlgorithm = ASN1Convert.ToOid (encodedCRL [1][0]);
|
|
if (signatureOID != signatureAlgorithm)
|
|
throw new CryptographicException (e + " [Non-matching signature algorithms in CRL]");
|
|
|
|
// CertificateList / BIT STRING
|
|
byte[] bitstring = encodedCRL [2].Value;
|
|
// first byte contains unused bits in first byte
|
|
signature = new byte [bitstring.Length - 1];
|
|
Buffer.BlockCopy (bitstring, 1, signature, 0, signature.Length);
|
|
}
|
|
catch {
|
|
throw new CryptographicException (e);
|
|
}
|
|
}
|
|
|
|
public ArrayList Entries {
|
|
get { return ArrayList.ReadOnly (entries); }
|
|
}
|
|
|
|
public X509CrlEntry this [int index] {
|
|
get { return (X509CrlEntry) entries [index]; }
|
|
}
|
|
|
|
public X509CrlEntry this [byte[] serialNumber] {
|
|
get { return GetCrlEntry (serialNumber); }
|
|
}
|
|
|
|
public X509ExtensionCollection Extensions {
|
|
get { return extensions; }
|
|
}
|
|
|
|
public byte[] Hash {
|
|
get {
|
|
if (hash_value == null) {
|
|
ASN1 encodedCRL = new ASN1 (encoded);
|
|
byte[] toBeSigned = encodedCRL [0].GetBytes ();
|
|
using (var ha = PKCS1.CreateFromOid (signatureOID))
|
|
hash_value = ha.ComputeHash (toBeSigned);
|
|
}
|
|
return hash_value;
|
|
}
|
|
}
|
|
|
|
public string IssuerName {
|
|
get { return issuer; }
|
|
}
|
|
|
|
public DateTime NextUpdate {
|
|
get { return nextUpdate; }
|
|
}
|
|
|
|
public DateTime ThisUpdate {
|
|
get { return thisUpdate; }
|
|
}
|
|
|
|
public string SignatureAlgorithm {
|
|
get { return signatureOID; }
|
|
}
|
|
|
|
public byte[] Signature {
|
|
get {
|
|
if (signature == null)
|
|
return null;
|
|
return (byte[]) signature.Clone ();
|
|
}
|
|
}
|
|
|
|
public byte[] RawData {
|
|
get { return (byte[]) encoded.Clone (); }
|
|
}
|
|
|
|
public byte Version {
|
|
get { return version; }
|
|
}
|
|
|
|
public bool IsCurrent {
|
|
get { return WasCurrent (DateTime.Now); }
|
|
}
|
|
|
|
public bool WasCurrent (DateTime instant)
|
|
{
|
|
if (nextUpdate == DateTime.MinValue)
|
|
return (instant >= thisUpdate);
|
|
else
|
|
return ((instant >= thisUpdate) && (instant <= nextUpdate));
|
|
}
|
|
|
|
public byte[] GetBytes ()
|
|
{
|
|
return (byte[]) encoded.Clone ();
|
|
}
|
|
|
|
private bool Compare (byte[] array1, byte[] array2)
|
|
{
|
|
if ((array1 == null) && (array2 == null))
|
|
return true;
|
|
if ((array1 == null) || (array2 == null))
|
|
return false;
|
|
if (array1.Length != array2.Length)
|
|
return false;
|
|
for (int i=0; i < array1.Length; i++) {
|
|
if (array1 [i] != array2 [i])
|
|
return false;
|
|
}
|
|
return true;
|
|
}
|
|
|
|
public X509CrlEntry GetCrlEntry (X509Certificate x509)
|
|
{
|
|
if (x509 == null)
|
|
throw new ArgumentNullException ("x509");
|
|
|
|
return GetCrlEntry (x509.SerialNumber);
|
|
}
|
|
|
|
public X509CrlEntry GetCrlEntry (byte[] serialNumber)
|
|
{
|
|
if (serialNumber == null)
|
|
throw new ArgumentNullException ("serialNumber");
|
|
|
|
for (int i=0; i < entries.Count; i++) {
|
|
X509CrlEntry entry = (X509CrlEntry) entries [i];
|
|
if (Compare (serialNumber, entry.SerialNumber))
|
|
return entry;
|
|
}
|
|
return null;
|
|
}
|
|
|
|
public bool VerifySignature (X509Certificate x509)
|
|
{
|
|
if (x509 == null)
|
|
throw new ArgumentNullException ("x509");
|
|
|
|
// 1. x509 certificate must be a CA certificate (unknown for v1 or v2 certs)
|
|
if (x509.Version >= 3) {
|
|
BasicConstraintsExtension basicConstraints = null;
|
|
// 1.2. Check for ca = true in BasicConstraint
|
|
X509Extension ext = x509.Extensions ["2.5.29.19"];
|
|
if (ext != null) {
|
|
basicConstraints = new BasicConstraintsExtension (ext);
|
|
if (!basicConstraints.CertificateAuthority)
|
|
return false;
|
|
}
|
|
// 1.1. Check for "cRLSign" bit in KeyUsage extension
|
|
ext = x509.Extensions ["2.5.29.15"];
|
|
if (ext != null) {
|
|
KeyUsageExtension keyUsage = new KeyUsageExtension (ext);
|
|
if (!keyUsage.Support (KeyUsages.cRLSign)) {
|
|
// 2nd chance if basicConstraints is CertificateAuthority
|
|
// and KeyUsage support digitalSignature
|
|
if ((basicConstraints == null) || !keyUsage.Support (KeyUsages.digitalSignature))
|
|
return false;
|
|
}
|
|
}
|
|
}
|
|
// 2. CRL issuer must match CA subject name
|
|
if (issuer != x509.SubjectName)
|
|
return false;
|
|
// 3. Check the CRL signature with the CA certificate public key
|
|
switch (signatureOID) {
|
|
case "1.2.840.10040.4.3":
|
|
return VerifySignature (x509.DSA);
|
|
default:
|
|
return VerifySignature (x509.RSA);
|
|
}
|
|
}
|
|
|
|
internal bool VerifySignature (DSA dsa)
|
|
{
|
|
if (signatureOID != "1.2.840.10040.4.3")
|
|
throw new CryptographicException ("Unsupported hash algorithm: " + signatureOID);
|
|
DSASignatureDeformatter v = new DSASignatureDeformatter (dsa);
|
|
// only SHA-1 is supported
|
|
v.SetHashAlgorithm ("SHA1");
|
|
ASN1 sign = new ASN1 (signature);
|
|
if ((sign == null) || (sign.Count != 2))
|
|
return false;
|
|
// parts may be less than 20 bytes (i.e. first bytes were 0x00)
|
|
byte[] part1 = sign [0].Value;
|
|
byte[] part2 = sign [1].Value;
|
|
byte[] sig = new byte [40];
|
|
// parts may be less than 20 bytes (i.e. first bytes were 0x00)
|
|
// parts may be more than 20 bytes (i.e. first byte > 0x80, negative)
|
|
int s1 = System.Math.Max (0, part1.Length - 20);
|
|
int e1 = System.Math.Max (0, 20 - part1.Length);
|
|
Buffer.BlockCopy (part1, s1, sig, e1, part1.Length - s1);
|
|
int s2 = System.Math.Max (0, part2.Length - 20);
|
|
int e2 = System.Math.Max (20, 40 - part2.Length);
|
|
Buffer.BlockCopy (part2, s2, sig, e2, part2.Length - s2);
|
|
return v.VerifySignature (Hash, sig);
|
|
}
|
|
|
|
internal bool VerifySignature (RSA rsa)
|
|
{
|
|
RSAPKCS1SignatureDeformatter v = new RSAPKCS1SignatureDeformatter (rsa);
|
|
v.SetHashAlgorithm (PKCS1.HashNameFromOid (signatureOID));
|
|
return v.VerifySignature (Hash, signature);
|
|
}
|
|
|
|
public bool VerifySignature (AsymmetricAlgorithm aa)
|
|
{
|
|
if (aa == null)
|
|
throw new ArgumentNullException ("aa");
|
|
|
|
// only validate the signature (in case we don't have the CA certificate)
|
|
if (aa is RSA)
|
|
return VerifySignature (aa as RSA);
|
|
else if (aa is DSA)
|
|
return VerifySignature (aa as DSA);
|
|
else
|
|
throw new NotSupportedException ("Unknown Asymmetric Algorithm " + aa.ToString ());
|
|
}
|
|
|
|
static public X509Crl CreateFromFile (string filename)
|
|
{
|
|
byte[] crl = null;
|
|
using (FileStream fs = File.Open (filename, FileMode.Open, FileAccess.Read, FileShare.Read)) {
|
|
crl = new byte [fs.Length];
|
|
fs.Read (crl, 0, crl.Length);
|
|
fs.Close ();
|
|
}
|
|
return new X509Crl (crl);
|
|
}
|
|
}
|
|
}
|