| Code with Finding: |
class SecureMessagingWrapper {
/*@ requires apdu != null && 4 <= len && len <= apdu.length;
*/
private byte[] wrapCommandAPDU(byte[] capdu, int len)
throws GeneralSecurityException, IOException {
if (capdu == null || capdu.length < 4 || len < 4) {
throw new IllegalArgumentException("Invalid type");
}
/* Determine lc and le... */
int lc = 0;
int le = capdu[len - 1] & 0x000000FF;
if (len == 4) {
lc = 0;
le = 0;
} else if (len == 5) {
/* No command data, byte at index 5 is le. */
lc = 0;
} else if (len > 5) {
/* Byte at index 5 is not le, so it must be lc. */
lc = capdu[ISO7816.OFFSET_LC] & 0x000000FF;
}
if (4 + lc >= len) {
/* Value of lc covers rest of apdu length, there is no le. */
le = 0;
}
ByteArrayOutputStream out = new ByteArrayOutputStream();
byte[] maskedHeader = new byte[4];
System.arraycopy(capdu, 0, maskedHeader, 0, 4);
maskedHeader[ISO7816.OFFSET_CLA] = (byte)0x0C;
byte[] paddedHeader = Util.pad(maskedHeader);
byte[] do87 = new byte[0];
byte[] do8E = new byte[0];
byte[] do97 = new byte[0];
if (le > 0) {
out.reset();
out.write((byte)0x97);
out.write((byte)0x01);
out.write((byte)le);
do97 = out.toByteArray();
}
if (lc > 0) {
byte[] data = Util.pad(capdu, ISO7816.OFFSET_CDATA, lc);
cipher.init(Cipher.ENCRYPT_MODE, ksEnc, ZERO_IV_PARAM_SPEC);
byte[] ciphertext = cipher.doFinal(data);
out.reset();
out.write((byte)0x87);
out.write((byte)(ciphertext.length + 1));
out.write(0x01);
out.write(ciphertext, 0, ciphertext.length);
do87 = out.toByteArray();
}
out.reset();
out.write(paddedHeader, 0, paddedHeader.length);
out.write(do87, 0, do87.length);
out.write(do97, 0, do97.length);
byte[] m = out.toByteArray();
out.reset();
DataOutputStream dataOut = new DataOutputStream(out);
ssc++;
dataOut.writeLong(ssc);
dataOut.write(m, 0, m.length);
dataOut.flush();
byte[] n = Util.pad(out.toByteArray());
/* Compute cryptographic checksum... */
mac.init(ksMac);
byte[] cc = mac.doFinal(n);
// ssc++; // TODO dit snappen
out.reset();
out.write((byte)0x8E);
out.write(cc.length);
out.write(cc, 0, cc.length);
do8E = out.toByteArray();
/* Construct protected apdu... */
out.reset();
out.write(maskedHeader, 0, 4);
out.write((byte)(do87.length + do97.length + do8E.length));
out.write(do87, 0, do87.length);
out.write(do97, 0, do97.length);
out.write(do8E, 0, do8E.length);
out.write(0x00);
return out.toByteArray();
}
}
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