diff options
Diffstat (limited to 'libraries/spongycastle/pkix/src/main/java/org/spongycastle/cms/KeyAgreeRecipientInfoGenerator.java')
| -rw-r--r-- | libraries/spongycastle/pkix/src/main/java/org/spongycastle/cms/KeyAgreeRecipientInfoGenerator.java | 80 |
1 files changed, 80 insertions, 0 deletions
diff --git a/libraries/spongycastle/pkix/src/main/java/org/spongycastle/cms/KeyAgreeRecipientInfoGenerator.java b/libraries/spongycastle/pkix/src/main/java/org/spongycastle/cms/KeyAgreeRecipientInfoGenerator.java new file mode 100644 index 000000000..b80ec3751 --- /dev/null +++ b/libraries/spongycastle/pkix/src/main/java/org/spongycastle/cms/KeyAgreeRecipientInfoGenerator.java @@ -0,0 +1,80 @@ +package org.spongycastle.cms; + +import java.io.IOException; + +import org.spongycastle.asn1.ASN1Encodable; +import org.spongycastle.asn1.ASN1EncodableVector; +import org.spongycastle.asn1.ASN1ObjectIdentifier; +import org.spongycastle.asn1.ASN1Sequence; +import org.spongycastle.asn1.DERNull; +import org.spongycastle.asn1.DEROctetString; +import org.spongycastle.asn1.cms.KeyAgreeRecipientInfo; +import org.spongycastle.asn1.cms.OriginatorIdentifierOrKey; +import org.spongycastle.asn1.cms.OriginatorPublicKey; +import org.spongycastle.asn1.cms.RecipientInfo; +import org.spongycastle.asn1.x509.AlgorithmIdentifier; +import org.spongycastle.asn1.x509.SubjectPublicKeyInfo; +import org.spongycastle.operator.GenericKey; + +public abstract class KeyAgreeRecipientInfoGenerator + implements RecipientInfoGenerator +{ + private ASN1ObjectIdentifier keyAgreementOID; + private ASN1ObjectIdentifier keyEncryptionOID; + private SubjectPublicKeyInfo originatorKeyInfo; + + protected KeyAgreeRecipientInfoGenerator(ASN1ObjectIdentifier keyAgreementOID, SubjectPublicKeyInfo originatorKeyInfo, ASN1ObjectIdentifier keyEncryptionOID) + { + this.originatorKeyInfo = originatorKeyInfo; + this.keyAgreementOID = keyAgreementOID; + this.keyEncryptionOID = keyEncryptionOID; + } + + public RecipientInfo generate(GenericKey contentEncryptionKey) + throws CMSException + { + OriginatorIdentifierOrKey originator = new OriginatorIdentifierOrKey( + createOriginatorPublicKey(originatorKeyInfo)); + + ASN1EncodableVector params = new ASN1EncodableVector(); + params.add(keyEncryptionOID); + params.add(DERNull.INSTANCE); + AlgorithmIdentifier keyEncAlg = new AlgorithmIdentifier(keyEncryptionOID, DERNull.INSTANCE); + AlgorithmIdentifier keyAgreeAlg = new AlgorithmIdentifier(keyAgreementOID, keyEncAlg); + + ASN1Sequence recipients = generateRecipientEncryptedKeys(keyAgreeAlg, keyEncAlg, contentEncryptionKey); + ASN1Encodable userKeyingMaterial = getUserKeyingMaterial(keyAgreeAlg); + + if (userKeyingMaterial != null) + { + try + { + return new RecipientInfo(new KeyAgreeRecipientInfo(originator, new DEROctetString(userKeyingMaterial), + keyAgreeAlg, recipients)); + } + catch (IOException e) + { + throw new CMSException("unable to encode userKeyingMaterial: " + e.getMessage(), e); + } + } + else + { + return new RecipientInfo(new KeyAgreeRecipientInfo(originator, null, + keyAgreeAlg, recipients)); + } + } + + protected OriginatorPublicKey createOriginatorPublicKey(SubjectPublicKeyInfo originatorKeyInfo) + { + return new OriginatorPublicKey( + new AlgorithmIdentifier(originatorKeyInfo.getAlgorithm().getAlgorithm(), DERNull.INSTANCE), + originatorKeyInfo.getPublicKeyData().getBytes()); + } + + protected abstract ASN1Sequence generateRecipientEncryptedKeys(AlgorithmIdentifier keyAgreeAlgorithm, AlgorithmIdentifier keyEncAlgorithm, GenericKey contentEncryptionKey) + throws CMSException; + + protected abstract ASN1Encodable getUserKeyingMaterial(AlgorithmIdentifier keyAgreeAlgorithm) + throws CMSException; + +}
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