void
XdmcpUnwrap (
unsigned char *input,
unsigned char *wrapper,
unsigned char *output,
int bytes)
{
int i, j, k;
unsigned char tmp[8];
unsigned char blocks[2][8];
unsigned char expand_wrapper[8];
auth_wrapper_schedule schedule;
_XdmcpWrapperToOddParity (wrapper, expand_wrapper);
_XdmcpAuthSetup (expand_wrapper, schedule);
k = 0;
for (j = 0; j < bytes; j += 8)
{
if (bytes - j < 8)
return; /* bad input length */
for (i = 0; i < 8; i++)
blocks[k][i] = input[j + i];
_XdmcpAuthDoIt ((unsigned char *) (input + j), (unsigned char *) tmp, schedule, 0);
/* block chaining */
k = (k == 0) ? 1 : 0;
for (i = 0; i < 8; i++)
{
if (j == 0)
output[j + i] = tmp[i];
else
output[j + i] = tmp[i] ^ blocks[k][i];
}
}
}
void
XdmcpWrap (
unsigned char *input,
unsigned char *wrapper,
unsigned char *output,
int bytes)
{
int i, j;
int len;
unsigned char tmp[8];
unsigned char expand_wrapper[8];
auth_wrapper_schedule schedule;
_XdmcpWrapperToOddParity (wrapper, expand_wrapper);
_XdmcpAuthSetup (expand_wrapper, schedule);
for (j = 0; j < bytes; j += 8)
{
len = 8;
if (bytes - j < len)
len = bytes - j;
/* block chaining */
for (i = 0; i < len; i++)
{
if (j == 0)
tmp[i] = input[i];
else
tmp[i] = input[j + i] ^ output[j - 8 + i];
}
for (; i < 8; i++)
{
if (j == 0)
tmp[i] = 0;
else
tmp[i] = 0 ^ output[j - 8 + i];
}
_XdmcpAuthDoIt (tmp, (output + j), schedule, 1);
}
}
