`--sftp=cipher-algos=...` specifies the allowed cipher algorithms. 
If unspecified then a sensible default is used.

Valid values: 
```
aes128-ctr
aes192-ctr
aes256-ctr
aes128******@****.***
******@****.***
******@****.***
arcfour256
arcfour128
arcfour
aes128-cbc
3des-cbc
```

`--sftp=mac-algos=...` specifies a default set of MAC algorithms in preference order.

        // Test HMAC-MD5
        byte[] mac1 = PacMac.calculateMac(PacSignature.KERB_CHECKSUM_HMAC_MD5, keys, TEST_DATA);
        assertNotNull(mac1);
        assertEquals(16, mac1.length);

        // Test AES128
        byte[] mac2 = PacMac.calculateMac(PacSignature.HMAC_SHA1_96_AES128, keys, TEST_DATA);
        assertNotNull(mac2);
        assertEquals(12, mac2.length);

        // Test AES256