Expose PGPOnePassSignature.isEncapsulating()

This method exposes the nested flag of OnePassSignatures.
Since the naming was a bit confusing, I renamed the flag to
isEncapsulating.

Exposing this flag to consumers is required for consumers to verify
the signature properly. Before this change, consumers would need to
encode the signature and access the correct byte to check the flag.

Author: vanitasvitae

pg/src/main/java/org/bouncycastle/bcpg/OnePassSignaturePacket.java

@@ -14,7 +14,7 @@ public class OnePassSignaturePacket
     private int  hashAlgorithm;
     private int  keyAlgorithm;
     private long keyID;
-    private int  nested;
+    private int isEncapsulating;
 
     OnePassSignaturePacket(
         BCPGInputStream    in)
@@ -34,7 +34,7 @@ public class OnePassSignaturePacket
         keyID |= (long)in.read() << 8;
         keyID |= in.read();
 
-        nested = in.read();
+        isEncapsulating = in.read();
     }
 
     public OnePassSignaturePacket(
@@ -49,7 +49,7 @@ public OnePassSignaturePacket(
         this.hashAlgorithm = hashAlgorithm;
         this.keyAlgorithm = keyAlgorithm;
         this.keyID = keyID;
-        this.nested = (isNested) ? 0 : 1;
+        this.isEncapsulating = (isNested) ? 0 : 1;
     }
 
     /**
@@ -84,6 +84,17 @@ public long getKeyID()
     {
         return keyID;
     }
+
+    /**
+     * Return true, if the signature is encapsulating.
+     * An encapsulating OPS is followed by additional OPS packets and is calculated over all the data between itself
+     * and its corresponding signature (it is an attestation for encapsulated signatures).
+     *
+     * @return true if encapsulating, false otherwise
+     */
+    public boolean isEncapsulating() {
+        return isEncapsulating == 1;
+    }
 
     /**
      * 
@@ -109,7 +120,7 @@ public void encode(
         pOut.write((byte)(keyID >> 8));
         pOut.write((byte)(keyID));
 
-        pOut.write(nested);
+        pOut.write(isEncapsulating);
 
         pOut.close();
 

pg/src/main/java/org/bouncycastle/openpgp/PGPOnePassSignature.java

@@ -203,6 +203,17 @@ public int getKeyAlgorithm()
         return sigPack.getKeyAlgorithm();
     }
 
+    /**
+     * Return true, if the signature is encapsulating.
+     * An encapsulating OPS is followed by additional OPS packets and is calculated over all the data between itself
+     * and its corresponding signature (it is an attestation for encapsulated signatures).
+     *
+     * @return true if encapsulating, false otherwise
+     */
+    public boolean isEncapsulating() {
+        return sigPack.isEncapsulating();
+    }
+
     public byte[] getEncoded()
         throws IOException
     {