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1public SecretKey kdf_AES_CMAC_SCP03_SYMKEY(SymmetricKey masterKey, byte[] context, byte kdfConstant,
2            int kdfOutputSizeBytes, boolean allowCounterData) throws EBaseException {
3
4         String method = "NistSP800_108KDF.kdf_AES_CMAC_SCP03_SYMKEY:";
5         String generatorInstanceName = null;
6
7         if (masterKey == null || context == null || kdfOutputSizeBytes <= 0) {
8            throw new EBaseException(method + " Invalid input!");
9         }
10        
11         // Decide if we want to allow extraction of derived key data for challenge strings.
12 
13         if(allowCounterData == true) {
14             generatorInstanceName = "KbkdfCounterData";
15         } else {
16             generatorInstanceName = "KbkdfCounter";
17         }
18
19          try {
20            /* We want a counter-mode KBKDF which generates data, not keys. */
21            KeyGenerator kg = KeyGenerator.getInstance(generatorInstanceName, "Mozilla-JSS");
22 System.err.println("Done  get KeyGenerator instance");
23            /* Start by building parameters for the Counter mode KDF. */
24            KBKDFCounterParams kcp = new KBKDFCounterParams();
25
26 System.err.println("Done new DBKDFCounterParams");
27
28            /* SCP03 mandates use of AES/CMAC for the KDF's PRF. */
29            kcp.setPRF(PKCS11Algorithm.CKM_AES_CMAC);
30
31 System.err.println("Done setPRF ");
32
33            SecretKey scMaster = new SecretKeyFacade(masterKey);
34            /* We've been passed the PRF key as master. */
35            kcp.setPRFKey(scMaster);
36
37 System.err.println("Done setPRFKey masterKey");
38
39            /* We've been passed the output size of the base key as kdfOutputSizeBytes. */
40            kcp.setKeySize(kdfOutputSizeBytes);
41
42 System.err.println("Done setKeySize");
43
44            /* Now we need to add the parameters for the SCP03 KDF. */
45
46            /* First is the 12-byte label. */
47            kcp.addParameter(new KBKDFByteArrayParam(new byte[] { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, kdfConstant }));
48
49            /* Then comes a one byte separation indicator. */
50            kcp.addParameter(new KBKDFByteArrayParam(new byte[] { 0x00 }));
51
52            /* Then comes the 2-byte, big-endian length parameter. Method doesn't matter as we only have a single key. Note that it is width in bits, not bytes. */
53            kcp.addParameter(new KBKDFDKMLengthParam(PKCS11Constants.CK_SP800_108_DKM_LENGTH_SUM_OF_SEGMENTS, true, 2*8));
54
55            /* Then comes a 1-byte counter. Endianness doesn't matter. Size in bits again. */
56            kcp.addParameter(new KBKDFIterationVariableParam(true, 1*8));
57
58            /* Lastly comes the context. */
59            kcp.addParameter(new KBKDFByteArrayParam(context));
60 System.err.println("Done adding parameters");
61
62             /* Pass our parameters to the KeyGenerator. */
63            kg.init(kcp);
64
65 System.err.println("Done  init kcp");
66
67
68            /* Return the derived key */
69
70            return kg.generateKey();
71
72        } catch (Exception e) {
73            throw new EBaseException(e.getMessage(), e);
74        }
75    }
76 
77    public byte[] kdf_AES_CMAC_SCP03_CHALLENGE(SymmetricKey masterKey, byte[] context, byte kdfConstant,
78            int kdfOutputSizeBytes) throws EBaseException {
79
80        String method = "NistSP800_108KDF.kdf_AES_CMAC_SCP03:";
81        // sanity checking
82
83        if (masterKey == null || context == null || kdfOutputSizeBytes <= 0) {
84            throw new EBaseException(method + " Invalid input!");
85        }
86        
87	try {
88            boolean allowCounterData = true;
89            SecretKey key = this.kdf_AES_CMAC_SCP03_SYMKEY(masterKey,context, kdfConstant,kdfOutputSizeBytes, allowCounterData);
90
91            /* Extract the value and return it. Only guaranteed to succeed in FIPS mode if KbkdfCounterData was used. */
92	    return key.getEncoded();
93        } catch (Exception e) {
94            throw new EBaseException(e.getMessage(), e);
95        }
96
97    }