/* * Copyright 1995-2016 The OpenSSL Project Authors. All Rights Reserved. * * Licensed under the Apache License 2.0 (the "License"). You may not use * this file except in compliance with the License. You can obtain a copy * in the file LICENSE in the source distribution or at * https://www.openssl.org/source/license.html */ #include #include "cast_local.h" /* * The input and output encrypted as though 64bit cfb mode is being used. * The extra state information to record how much of the 64bit block we have * used is contained in *num; */ void CAST_cfb64_encrypt(const unsigned char *in, unsigned char *out, long length, const CAST_KEY *schedule, unsigned char *ivec, int *num, int enc) { register CAST_LONG v0, v1, t; register int n = *num; register long l = length; CAST_LONG ti[2]; unsigned char *iv, c, cc; iv = ivec; if (enc) { while (l--) { if (n == 0) { n2l(iv, v0); ti[0] = v0; n2l(iv, v1); ti[1] = v1; CAST_encrypt((CAST_LONG *)ti, schedule); iv = ivec; t = ti[0]; l2n(t, iv); t = ti[1]; l2n(t, iv); iv = ivec; } c = *(in++) ^ iv[n]; *(out++) = c; iv[n] = c; n = (n + 1) & 0x07; } } else { while (l--) { if (n == 0) { n2l(iv, v0); ti[0] = v0; n2l(iv, v1); ti[1] = v1; CAST_encrypt((CAST_LONG *)ti, schedule); iv = ivec; t = ti[0]; l2n(t, iv); t = ti[1]; l2n(t, iv); iv = ivec; } cc = *(in++); c = iv[n]; iv[n] = cc; *(out++) = c ^ cc; n = (n + 1) & 0x07; } } v0 = v1 = ti[0] = ti[1] = t = c = cc = 0; *num = n; }