3rdPartyLibraries/iTechSharp/srcbc/cms/CMSSignedDataParser.cs
2023-06-21 12:46:23 -04:00

566 lines
15 KiB
C#

using System;
using System.Collections;
using System.IO;
using Org.BouncyCastle.Asn1;
using Org.BouncyCastle.Asn1.Cms;
using Org.BouncyCastle.Asn1.X509;
using Org.BouncyCastle.Crypto;
using Org.BouncyCastle.Crypto.IO;
using Org.BouncyCastle.Security;
using Org.BouncyCastle.Security.Certificates;
using Org.BouncyCastle.Utilities;
using Org.BouncyCastle.Utilities.IO;
using Org.BouncyCastle.X509;
using Org.BouncyCastle.X509.Store;
namespace Org.BouncyCastle.Cms
{
/**
* Parsing class for an CMS Signed Data object from an input stream.
* <p>
* Note: that because we are in a streaming mode only one signer can be tried and it is important
* that the methods on the parser are called in the appropriate order.
* </p>
* <p>
* A simple example of usage for an encapsulated signature.
* </p>
* <p>
* Two notes: first, in the example below the validity of
* the certificate isn't verified, just the fact that one of the certs
* matches the given signer, and, second, because we are in a streaming
* mode the order of the operations is important.
* </p>
* <pre>
* CmsSignedDataParser sp = new CmsSignedDataParser(encapSigData);
*
* sp.GetSignedContent().Drain();
*
* IX509Store certs = sp.GetCertificates();
* SignerInformationStore signers = sp.GetSignerInfos();
*
* foreach (SignerInformation signer in signers.GetSigners())
* {
* ArrayList certList = new ArrayList(certs.GetMatches(signer.SignerID));
* X509Certificate cert = (X509Certificate) certList[0];
*
* Console.WriteLine("verify returns: " + signer.Verify(cert));
* }
* </pre>
* Note also: this class does not introduce buffering - if you are processing large files you should create
* the parser with:
* <pre>
* CmsSignedDataParser ep = new CmsSignedDataParser(new BufferedInputStream(encapSigData, bufSize));
* </pre>
* where bufSize is a suitably large buffer size.
*/
public class CmsSignedDataParser
: CmsContentInfoParser
{
private static readonly CmsSignedHelper Helper = CmsSignedHelper.Instance;
private SignedDataParser _signedData;
private CmsTypedStream _signedContent;
private IDictionary _digests;
private SignerInformationStore _signerInfoStore;
private Asn1Set _certSet, _crlSet;
private bool _isCertCrlParsed;
private IX509Store _attributeStore;
private IX509Store _certificateStore;
private IX509Store _crlStore;
public CmsSignedDataParser(
byte[] sigBlock)
: this(new MemoryStream(sigBlock, false))
{
}
public CmsSignedDataParser(
CmsTypedStream signedContent,
byte[] sigBlock)
: this(signedContent, new MemoryStream(sigBlock, false))
{
}
/**
* base constructor - with encapsulated content
*/
public CmsSignedDataParser(
Stream sigData)
: this(null, sigData)
{
}
/**
* base constructor
*
* @param signedContent the content that was signed.
* @param sigData the signature object.
*/
public CmsSignedDataParser(
CmsTypedStream signedContent,
Stream sigData)
: base(sigData)
{
try
{
this._signedContent = signedContent;
this._signedData = SignedDataParser.GetInstance(this.contentInfo.GetContent(Asn1Tags.Sequence));
this._digests = new Hashtable();
Asn1SetParser digAlgs = _signedData.GetDigestAlgorithms();
IAsn1Convertible o;
while ((o = digAlgs.ReadObject()) != null)
{
AlgorithmIdentifier id = AlgorithmIdentifier.GetInstance(o.ToAsn1Object());
try
{
string digestName = Helper.GetDigestAlgName(id.ObjectID.Id);
IDigest dig = Helper.GetDigestInstance(digestName);
this._digests[digestName] = dig;
}
catch (SecurityUtilityException)
{
// ignore
}
}
//
// If the message is simply a certificate chain message GetContent() may return null.
//
ContentInfoParser cont = _signedData.GetEncapContentInfo();
Asn1OctetStringParser octs = (Asn1OctetStringParser)
cont.GetContent(Asn1Tags.OctetString);
if (octs != null)
{
CmsTypedStream ctStr = new CmsTypedStream(
cont.ContentType.Id, octs.GetOctetStream());
if (_signedContent == null)
{
this._signedContent = ctStr;
}
else
{
//
// content passed in, need to read past empty encapsulated content info object if present
//
ctStr.Drain();
}
}
}
catch (IOException e)
{
throw new CmsException("io exception: " + e.Message, e);
}
if (_digests.Count < 1)
{
throw new CmsException("no digests could be created for message.");
}
}
/**
* Return the version number for the SignedData object
*
* @return the version number
*/
public int Version
{
get { return _signedData.Version.Value.IntValue; }
}
/**
* return the collection of signers that are associated with the
* signatures for the message.
* @throws CmsException
*/
public SignerInformationStore GetSignerInfos()
{
if (_signerInfoStore == null)
{
PopulateCertCrlSets();
IList signerInfos = new ArrayList();
IDictionary hashes = new Hashtable();
foreach (object digestKey in _digests.Keys)
{
hashes[digestKey] = DigestUtilities.DoFinal(
(IDigest)_digests[digestKey]);
}
try
{
Asn1SetParser s = _signedData.GetSignerInfos();
IAsn1Convertible o;
while ((o = s.ReadObject()) != null)
{
SignerInfo info = SignerInfo.GetInstance(o.ToAsn1Object());
string digestName = Helper.GetDigestAlgName(
info.DigestAlgorithm.ObjectID.Id);
byte[] hash = (byte[]) hashes[digestName];
DerObjectIdentifier oid = new DerObjectIdentifier(_signedContent.ContentType);
signerInfos.Add(new SignerInformation(info, oid, null, new BaseDigestCalculator(hash)));
}
}
catch (IOException e)
{
throw new CmsException("io exception: " + e.Message, e);
}
_signerInfoStore = new SignerInformationStore(signerInfos);
}
return _signerInfoStore;
}
/**
* return a X509Store containing the attribute certificates, if any, contained
* in this message.
*
* @param type type of store to create
* @return a store of attribute certificates
* @exception org.bouncycastle.x509.NoSuchStoreException if the store type isn't available.
* @exception CmsException if a general exception prevents creation of the X509Store
*/
public IX509Store GetAttributeCertificates(
string type)
{
if (_attributeStore == null)
{
PopulateCertCrlSets();
_attributeStore = Helper.CreateAttributeStore(type, _certSet);
}
return _attributeStore;
}
/**
* return a X509Store containing the public key certificates, if any, contained
* in this message.
*
* @param type type of store to create
* @return a store of public key certificates
* @exception NoSuchStoreException if the store type isn't available.
* @exception CmsException if a general exception prevents creation of the X509Store
*/
public IX509Store GetCertificates(
string type)
{
if (_certificateStore == null)
{
PopulateCertCrlSets();
_certificateStore = Helper.CreateCertificateStore(type, _certSet);
}
return _certificateStore;
}
/**
* return a X509Store containing CRLs, if any, contained
* in this message.
*
* @param type type of store to create
* @return a store of CRLs
* @exception NoSuchStoreException if the store type isn't available.
* @exception CmsException if a general exception prevents creation of the X509Store
*/
public IX509Store GetCrls(
string type)
{
if (_crlStore == null)
{
PopulateCertCrlSets();
_crlStore = Helper.CreateCrlStore(type, _crlSet);
}
return _crlStore;
}
private void PopulateCertCrlSets()
{
if (_isCertCrlParsed)
return;
_isCertCrlParsed = true;
try
{
// care! Streaming - Must process the GetCertificates() result before calling GetCrls()
_certSet = GetAsn1Set(_signedData.GetCertificates());
_crlSet = GetAsn1Set(_signedData.GetCrls());
}
catch (IOException e)
{
throw new CmsException("problem parsing cert/crl sets", e);
}
}
public CmsTypedStream GetSignedContent()
{
if (_signedContent == null)
{
return null;
}
Stream digStream = _signedContent.ContentStream;
foreach (IDigest digest in _digests.Values)
{
digStream = new DigestStream(digStream, digest, null);
}
return new CmsTypedStream(_signedContent.ContentType, digStream);
}
/**
* Replace the signerinformation store associated with the passed
* in message contained in the stream original with the new one passed in.
* You would probably only want to do this if you wanted to change the unsigned
* attributes associated with a signer, or perhaps delete one.
* <p>
* The output stream is returned unclosed.
* </p>
* @param original the signed data stream to be used as a base.
* @param signerInformationStore the new signer information store to use.
* @param out the stream to Write the new signed data object to.
* @return out.
*/
public static Stream ReplaceSigners(
Stream original,
SignerInformationStore signerInformationStore,
Stream outStr)
{
Asn1StreamParser inStr = new Asn1StreamParser(original, CmsUtilities.MaximumMemory);
ContentInfoParser contentInfo = new ContentInfoParser((Asn1SequenceParser)inStr.ReadObject());
SignedDataParser signedData = SignedDataParser.GetInstance(contentInfo.GetContent(Asn1Tags.Sequence));
BerSequenceGenerator sGen = new BerSequenceGenerator(outStr);
sGen.AddObject(CmsObjectIdentifiers.SignedData);
BerSequenceGenerator sigGen = new BerSequenceGenerator(sGen.GetRawOutputStream(), 0, true);
// version number
sigGen.AddObject(signedData.Version);
// digests
signedData.GetDigestAlgorithms().ToAsn1Object(); // skip old ones
Asn1EncodableVector digestAlgs = new Asn1EncodableVector();
foreach (SignerInformation signer in signerInformationStore.GetSigners())
{
digestAlgs.Add(FixAlgID(signer.DigestAlgorithmID));
}
WriteToGenerator(sigGen, new DerSet(digestAlgs));
// encap content info
ContentInfoParser encapContentInfo = signedData.GetEncapContentInfo();
BerSequenceGenerator eiGen = new BerSequenceGenerator(sigGen.GetRawOutputStream());
eiGen.AddObject(encapContentInfo.ContentType);
Asn1OctetStringParser octs = (Asn1OctetStringParser)encapContentInfo.GetContent(Asn1Tags.OctetString);
if (octs != null)
{
PipeOctetString(octs, eiGen.GetRawOutputStream());
}
eiGen.Close();
WriteSetToGeneratorTagged(sigGen, signedData.GetCertificates(), 0);
WriteSetToGeneratorTagged(sigGen, signedData.GetCrls(), 1);
Asn1EncodableVector signerInfos = new Asn1EncodableVector();
foreach (SignerInformation signer in signerInformationStore.GetSigners())
{
signerInfos.Add(signer.ToSignerInfo());
}
WriteToGenerator(sigGen, new DerSet(signerInfos));
sigGen.Close();
sGen.Close();
return outStr;
}
/**
* Replace the certificate and CRL information associated with this
* CMSSignedData object with the new one passed in.
* <p>
* The output stream is returned unclosed.
* </p>
* @param original the signed data stream to be used as a base.
* @param certsAndCrls the new certificates and CRLs to be used.
* @param out the stream to Write the new signed data object to.
* @return out.
* @exception CmsException if there is an error processing the CertStore
*/
public static Stream ReplaceCertificatesAndCrls(
Stream original,
IX509Store x509Certs,
IX509Store x509Crls,
IX509Store x509AttrCerts,
Stream outStr)
{
if (x509AttrCerts != null)
throw Platform.CreateNotImplementedException("Currently can't replace attribute certificates");
Asn1StreamParser inStr = new Asn1StreamParser(original, CmsUtilities.MaximumMemory);
ContentInfoParser contentInfo = new ContentInfoParser((Asn1SequenceParser)inStr.ReadObject());
SignedDataParser signedData = SignedDataParser.GetInstance(contentInfo.GetContent(Asn1Tags.Sequence));
BerSequenceGenerator sGen = new BerSequenceGenerator(outStr);
sGen.AddObject(CmsObjectIdentifiers.SignedData);
BerSequenceGenerator sigGen = new BerSequenceGenerator(sGen.GetRawOutputStream(), 0, true);
// version number
sigGen.AddObject(signedData.Version);
// digests
WriteToGenerator(sigGen, signedData.GetDigestAlgorithms().ToAsn1Object());
// encap content info
ContentInfoParser encapContentInfo = signedData.GetEncapContentInfo();
BerSequenceGenerator eiGen = new BerSequenceGenerator(sigGen.GetRawOutputStream());
eiGen.AddObject(encapContentInfo.ContentType);
Asn1OctetStringParser octs = (Asn1OctetStringParser)
encapContentInfo.GetContent(Asn1Tags.OctetString);
if (octs != null)
{
PipeOctetString(octs, eiGen.GetRawOutputStream());
}
eiGen.Close();
//
// skip existing certs and CRLs
//
GetAsn1Set(signedData.GetCertificates());
GetAsn1Set(signedData.GetCrls());
//
// replace the certs and crls in the SignedData object
//
Asn1Set certs;
try
{
certs = CmsUtilities.CreateBerSetFromList(
CmsUtilities.GetCertificatesFromStore(x509Certs));
}
catch (X509StoreException e)
{
throw new CmsException("error getting certs from certStore", e);
}
if (certs.Count > 0)
{
WriteToGenerator(sigGen, new DerTaggedObject(false, 0, certs));
}
Asn1Set crls;
try
{
crls = CmsUtilities.CreateBerSetFromList(
CmsUtilities.GetCrlsFromStore(x509Crls));
}
catch (X509StoreException e)
{
throw new CmsException("error getting crls from certStore", e);
}
if (crls.Count > 0)
{
WriteToGenerator(sigGen, new DerTaggedObject(false, 1, crls));
}
WriteToGenerator(sigGen, signedData.GetSignerInfos().ToAsn1Object());
sigGen.Close();
sGen.Close();
return outStr;
}
private static AlgorithmIdentifier FixAlgID(
AlgorithmIdentifier algId)
{
if (algId.Parameters == null)
return new AlgorithmIdentifier(algId.ObjectID, DerNull.Instance);
return algId;
}
private static void WriteSetToGeneratorTagged(
Asn1Generator asn1Gen,
Asn1SetParser asn1SetParser,
int tagNo)
{
Asn1Set asn1Set = GetAsn1Set(asn1SetParser);
if (asn1Set != null)
{
Asn1TaggedObject taggedObj = (asn1SetParser is BerSetParser)
? new BerTaggedObject(false, tagNo, asn1Set)
: new DerTaggedObject(false, tagNo, asn1Set);
WriteToGenerator(asn1Gen, taggedObj);
}
}
private static Asn1Set GetAsn1Set(
Asn1SetParser asn1SetParser)
{
return asn1SetParser == null
? null
: Asn1Set.GetInstance(asn1SetParser.ToAsn1Object());
}
private static void WriteToGenerator(
Asn1Generator ag,
Asn1Encodable ae)
{
byte[] encoded = ae.GetEncoded();
ag.GetRawOutputStream().Write(encoded, 0, encoded.Length);
}
private static void PipeOctetString(
Asn1OctetStringParser octs,
Stream output)
{
BerOctetStringGenerator octGen = new BerOctetStringGenerator(output, 0, true);
// TODO Allow specification of a specific fragment size?
Stream outOctets = octGen.GetOctetOutputStream();
Streams.PipeAll(octs.GetOctetStream(), outOctets);
outOctets.Close();
}
}
}