1 /* 2 * Copyright 1995-2016 The OpenSSL Project Authors. All Rights Reserved. 3 * 4 * Licensed under the OpenSSL license (the "License"). You may not use 5 * this file except in compliance with the License. You can obtain a copy 6 * in the file LICENSE in the source distribution or at 7 * https://www.openssl.org/source/license.html 8 */ 9 10 #include "des_locl.h" 11 12 /* 13 * The input and output encrypted as though 64bit ofb mode is being used. 14 * The extra state information to record how much of the 64bit block we have 15 * used is contained in *num; 16 */ 17 void DES_ofb64_encrypt(register const unsigned char *in, 18 register unsigned char *out, long length, 19 DES_key_schedule *schedule, DES_cblock *ivec, int *num) 20 { 21 register DES_LONG v0, v1, t; 22 register int n = *num; 23 register long l = length; 24 DES_cblock d; 25 register unsigned char *dp; 26 DES_LONG ti[2]; 27 unsigned char *iv; 28 int save = 0; 29 30 iv = &(*ivec)[0]; 31 c2l(iv, v0); 32 c2l(iv, v1); 33 ti[0] = v0; 34 ti[1] = v1; 35 dp = d; 36 l2c(v0, dp); 37 l2c(v1, dp); 38 while (l--) { 39 if (n == 0) { 40 DES_encrypt1(ti, schedule, DES_ENCRYPT); 41 dp = d; 42 t = ti[0]; 43 l2c(t, dp); 44 t = ti[1]; 45 l2c(t, dp); 46 save++; 47 } 48 *(out++) = *(in++) ^ d[n]; 49 n = (n + 1) & 0x07; 50 } 51 if (save) { 52 v0 = ti[0]; 53 v1 = ti[1]; 54 iv = &(*ivec)[0]; 55 l2c(v0, iv); 56 l2c(v1, iv); 57 } 58 t = v0 = v1 = ti[0] = ti[1] = 0; 59 *num = n; 60 } 61