1 files changed, 33 insertions, 0 deletions
diff --git a/libraries/spongycastle/pkix/src/main/java/org/spongycastle/cert/selector/MSOutlookKeyIdCalculator.java b/libraries/spongycastle/pkix/src/main/java/org/spongycastle/cert/selector/MSOutlookKeyIdCalculator.java
new file mode 100644
index 000000000..e52e6222e
--- /dev/null
+++ b/libraries/spongycastle/pkix/src/main/java/org/spongycastle/cert/selector/MSOutlookKeyIdCalculator.java
@@ -0,0 +1,33 @@
+package org.spongycastle.cert.selector;
+
+import java.io.IOException;
+
+import org.spongycastle.asn1.ASN1Encoding;
+import org.spongycastle.asn1.x509.SubjectPublicKeyInfo;
+import org.spongycastle.crypto.Digest;
+import org.spongycastle.crypto.digests.SHA1Digest;
+
+class MSOutlookKeyIdCalculator
+{
+    static byte[] calculateKeyId(SubjectPublicKeyInfo info)
+    {
+        Digest dig = new SHA1Digest();    // TODO: include definition of SHA-1 here
+        byte[] hash = new byte[dig.getDigestSize()];
+        byte[] spkiEnc = new byte[0];
+        try
+        {
+            spkiEnc = info.getEncoded(ASN1Encoding.DER);
+        }
+        catch (IOException e)
+        {
+            return new byte[0];
+        }
+
+        // try the outlook 2010 calculation
+        dig.update(spkiEnc, 0, spkiEnc.length);
+
+        dig.doFinal(hash, 0);
+
+        return hash;
+    }
+}