1 files changed, 79 insertions, 0 deletions
diff --git a/Crypto/src/cms/PasswordRecipientInformation.cs b/Crypto/src/cms/PasswordRecipientInformation.cs
new file mode 100644
index 000000000..f629caba6
--- /dev/null
+++ b/Crypto/src/cms/PasswordRecipientInformation.cs
@@ -0,0 +1,79 @@
+using System;
+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.Parameters;
+using Org.BouncyCastle.Security;
+
+namespace Org.BouncyCastle.Cms
+{
+ /**
+ * the RecipientInfo class for a recipient who has been sent a message
+ * encrypted using a password.
+ */
+ public class PasswordRecipientInformation
+ : RecipientInformation
+ {
+ private readonly PasswordRecipientInfo info;
+
+ internal PasswordRecipientInformation(
+ PasswordRecipientInfo info,
+ CmsSecureReadable secureReadable)
+ : base(info.KeyEncryptionAlgorithm, secureReadable)
+ {
+ this.info = info;
+ this.rid = new RecipientID();
+ }
+
+ /**
+ * return the object identifier for the key derivation algorithm, or null
+ * if there is none present.
+ *
+ * @return OID for key derivation algorithm, if present.
+ */
+ public virtual AlgorithmIdentifier KeyDerivationAlgorithm
+ {
+ get { return info.KeyDerivationAlgorithm; }
+ }
+
+ /**
+ * decrypt the content and return an input stream.
+ */
+ public override CmsTypedStream GetContentStream(
+ ICipherParameters key)
+ {
+ try
+ {
+ AlgorithmIdentifier kekAlg = AlgorithmIdentifier.GetInstance(info.KeyEncryptionAlgorithm);
+ Asn1Sequence kekAlgParams = (Asn1Sequence)kekAlg.Parameters;
+ byte[] encryptedKey = info.EncryptedKey.GetOctets();
+ string kekAlgName = DerObjectIdentifier.GetInstance(kekAlgParams[0]).Id;
+ string cName = CmsEnvelopedHelper.Instance.GetRfc3211WrapperName(kekAlgName);
+ IWrapper keyWrapper = WrapperUtilities.GetWrapper(cName);
+
+ byte[] iv = Asn1OctetString.GetInstance(kekAlgParams[1]).GetOctets();
+
+ ICipherParameters parameters = ((CmsPbeKey)key).GetEncoded(kekAlgName);
+ parameters = new ParametersWithIV(parameters, iv);
+
+ keyWrapper.Init(false, parameters);
+
+ KeyParameter sKey = ParameterUtilities.CreateKeyParameter(
+ GetContentAlgorithmName(), keyWrapper.Unwrap(encryptedKey, 0, encryptedKey.Length));
+
+ return GetContentFromSessionKey(sKey);
+ }
+ catch (SecurityUtilityException e)
+ {
+ throw new CmsException("couldn't create cipher.", e);
+ }
+ catch (InvalidKeyException e)
+ {
+ throw new CmsException("key invalid in message.", e);
+ }
+ }
+ }
+}
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