/* * $Xorg: Wrap.c,v 1.4 2001/02/09 02:03:49 xorgcvs Exp $ * * Copyright 1989, 1998 The Open Group Permission to use, copy, modify, distribute, and sell this software and its documentation for any purpose is hereby granted without fee, provided that the above copyright notice appear in all copies and that both that copyright notice and this permission notice appear in supporting documentation. The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software. THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE OPEN GROUP BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. Except as contained in this notice, the name of The Open Group shall not be used in advertising or otherwise to promote the sale, use or other dealings in this Software without prior written authorization from The Open Group. * * * Author: Keith Packard, MIT X Consortium */ /* $XFree86: xc/lib/Xdmcp/Wrap.c,v 1.3 2001/01/17 19:42:44 dawes Exp $ */ #ifdef HAVE_CONFIG_H #include <config.h> #endif #include <X11/Xos.h> #include <X11/X.h> #include <X11/Xmd.h> #include <X11/Xdmcp.h> #ifdef HASXDMAUTH /* * The following function exists only to demonstrate the * desired functional interface for this routine. You will * need to add the appropriate algorithm if you wish to * use XDM-AUTHENTICATION-1/XDM-AUTHORIZATION-1. * * Examine the XDMCP specification for the correct algorithm */ #include "Wrap.h" 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); } } /* * Given a 56 bit wrapper in XDMCP format, create a 56 * bit wrapper in 7-bits + odd parity format */ static int OddParity (unsigned char c) { c = c ^ (c >> 4); c = c ^ (c >> 2); c = c ^ (c >> 1); return ~c & 0x1; } /* * Spread the 56 bit wrapper among 8 bytes, using the upper 7 bits * of each byte, and storing an odd parity bit in the low bit */ void _XdmcpWrapperToOddParity ( unsigned char *in, unsigned char *out) { int ashift, bshift; int i; unsigned char c; ashift = 7; bshift = 1; for (i = 0; i < 7; i++) { c = ((in[i] << ashift) | (in[i+1] >> bshift)) & 0x7f; out[i] = (c << 1) | OddParity (c); ashift--; bshift++; } c = in[i]; out[i] = (c << 1) | OddParity(c); } #endif