Cryptographic Token Interface Standard

PKCS#11


XORing of a key and data

XORing key derivation, denoted CKM_XOR_BASE_AND_DATA, is a mechanism which provides the capability of deriving a secret key by performing a bit XORing of a key pointed to by a base key handle and some data.

This mechanism takes a parameter, a CK_KEY_DERIVATION_STRING_DATA structure, which specifies the data with which to XOR the original key's value.

For example, if the value of the base key is 0x01234567, and the value of the data is 0x89ABCDEF, then the value of the derived key will be taken from a buffer containing the string 0x88888888.

If the requested type of key requires more bytes than are available by taking the shorter of the data and the original key's value, an error is generated.

This mechanism has the following rules about key sensitivity and extractability:


RSA Security Inc. Public-Key Cryptography Standards - PKCS#11 - v210