/* ofb_enc.c */ /* Copyright (C) 1993 Eric Young - see README for more details */ /*- * $Id: ofb_enc.c,v 1.2 1994/07/19 19:21:59 g89r4222 Exp $ */ #include "des_locl.h" /* The input and output are loaded in multiples of 8 bits. * What this means is that if you hame numbits=12 and length=2 * the first 12 bits will be retrieved from the first byte and half * the second. The second 12 bits will come from the 3rd and half the 4th * byte. */ int des_ofb_encrypt(in,out,numbits,length,schedule,ivec) unsigned char *in,*out; int numbits; long length; des_key_schedule schedule; des_cblock *ivec; { register unsigned long d0,d1,v0,v1,n=(numbits+7)/8; register unsigned long mask0,mask1; register long l=length; register int num=numbits; unsigned long ti[2]; unsigned char *iv; if (num > 64) return(0); if (num > 32) { mask0=0xffffffff; if (num >= 64) mask1=mask0; else mask1=(1L<<(num-32))-1; } else { if (num == 32) mask0=0xffffffff; else mask0=(1L< 0) { des_encrypt((unsigned long *)ti,(unsigned long *)ti, schedule,DES_ENCRYPT); c2ln(in,d0,d1,n); in+=n; d0=(d0^ti[0])&mask0; d1=(d1^ti[1])&mask1; l2cn(d0,d1,out,n); out+=n; } v0=ti[0]; v1=ti[1]; iv=(unsigned char *)ivec; l2c(v0,iv); l2c(v1,iv); v0=v1=d0=d1=ti[0]=ti[1]=0; return(0); }