void IDEA_cfb64_encrypt(const unsigned char *in, unsigned char *out,
long length, IDEA_KEY_SCHEDULE *schedule,
unsigned char *ivec, int *num, int encrypt)
{
register IDEA_INT v0, v1, t;
register int n = *num;
register long l = length;
IDEA_INT ti[2];
unsigned char *iv, c, cc;
iv = (unsigned char *)ivec;
if (encrypt) {
while (l--) {
if (n == 0) {
n2l(iv, v0);
ti[0] = v0;
n2l(iv, v1);
ti[1] = v1;
IDEA_encrypt(ti, schedule);
iv = (unsigned char *)ivec;
t = ti[0];
l2n(t, iv);
t = ti[1];
l2n(t, iv);
iv = (unsigned char *)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;
IDEA_encrypt(ti, schedule);
iv = (unsigned char *)ivec;
t = ti[0];
l2n(t, iv);
t = ti[1];
l2n(t, iv);
iv = (unsigned char *)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;
}
/*
* The input and output encrypted as though 64bit ofb mode is being used.
* The extra state information to record how much of the 64bit block we have
* used is contained in *num;
*/
void IDEA_ofb64_encrypt(const unsigned char *in, unsigned char *out,
long length, IDEA_KEY_SCHEDULE *schedule,
unsigned char *ivec, int *num)
{
register unsigned long v0, v1, t;
register int n = *num;
register long l = length;
unsigned char d[8];
register char *dp;
unsigned long ti[2];
unsigned char *iv;
int save = 0;
iv = (unsigned char *)ivec;
n2l(iv, v0);
n2l(iv, v1);
ti[0] = v0;
ti[1] = v1;
dp = (char *)d;
l2n(v0, dp);
l2n(v1, dp);
while (l--) {
if (n == 0) {
IDEA_encrypt((unsigned long *)ti, schedule);
dp = (char *)d;
t = ti[0];
l2n(t, dp);
t = ti[1];
l2n(t, dp);
save++;
}
*(out++) = *(in++) ^ d[n];
n = (n + 1) & 0x07;
}
if (save) {
v0 = ti[0];
v1 = ti[1];
iv = (unsigned char *)ivec;
l2n(v0, iv);
l2n(v1, iv);
}
t = v0 = v1 = ti[0] = ti[1] = 0;
*num = n;
}
