/*
 * authorization hooks for the server
 *
 * $XConsortium: auth.c,v 1.3 94/04/17 21:17:11 dpw Exp $
 *
Copyright (c) 1994  X Consortium

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

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
X CONSORTIUM 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 X Consortium 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 X Consortium.
 * Author:  Keith Packard, MIT X Consortium
 */

#ifdef K5AUTH
# include   <krb5/krb5.h>
#endif
# include   "X.h"
# include   "Xauth.h"
# include   "misc.h"
# include   "dixstruct.h"
# include   <sys/types.h>
# include   <sys/stat.h>

struct protocol {
    unsigned short   name_length;
    char    *name;
    int     (*Add)();	    /* new authorization data */
    XID	    (*Check)();	    /* verify client authorization data */
    int     (*Reset)();	    /* delete all authorization data entries */
    XID	    (*ToID)();	    /* convert cookie to ID */
    int	    (*FromID)();    /* convert ID to cookie */
    int	    (*Remove)();    /* remove a specific cookie */
};

#ifdef HASXDMAUTH
extern int  XdmAddCookie ();
extern XID  XdmCheckCookie ();
extern int  XdmResetCookie ();
extern XID  XdmToID ();
extern int  XdmFromID (), XdmRemoveCookie ();
#endif

#ifdef SECURE_RPC
extern int  SecureRPCAdd();
extern XID  SecureRPCCheck();
extern int  SecureRPCReset();
extern XID  SecureRPCToID();
extern int  SecureRPCFromID(), SecureRPCRemove();
#endif

#ifdef K5AUTH
extern int K5Add();
extern XID K5Check();
extern int K5Reset();
extern XID K5ToID();
extern int K5FromID(), K5Remove();
#endif

static struct protocol   protocols[] = {
#ifdef HASXDMAUTH
{   (unsigned short) 19,    "XDM-AUTHORIZATION-1",
		XdmAddCookie,	XdmCheckCookie,	XdmResetCookie,
		XdmToID,	XdmFromID,	XdmRemoveCookie,
},
#endif
#ifdef SECURE_RPC
{   (unsigned short) 9,    "SUN-DES-1",
		SecureRPCAdd,	SecureRPCCheck,	SecureRPCReset,
		SecureRPCToID,	SecureRPCFromID,SecureRPCRemove,
},
#endif
#ifdef K5AUTH
{   (unsigned short) 14, "MIT-KERBEROS-5",
		K5Add, K5Check, K5Reset,
		K5ToID, K5FromID, K5Remove,
},
#endif
};

# define NUM_AUTHORIZATION  (sizeof (protocols) /\
			     sizeof (struct protocol))

/*
 * Initialize all classes of authorization by reading the
 * specified authorization file
 */

static char *authorization_file = (char *)NULL;

static int  AuthorizationIndex = 0;
static Bool ShouldLoadAuth = TRUE;

void
InitAuthorization (file_name)
char	*file_name;
{
    authorization_file = file_name;
}

int
LoadAuthorization ()
{
    FILE    *f;
    Xauth   *auth;
    int	    i;
    int	    count = 0;

    ShouldLoadAuth = FALSE;
    if (!authorization_file)
	return 0;
    f = fopen (authorization_file, "r");
    if (!f)
	return 0;
    AuthorizationIndex = 0;
    while (auth = XauReadAuth (f)) {
	for (i = 0; i < NUM_AUTHORIZATION; i++) {
	    if (protocols[i].name_length == auth->name_length &&
		memcmp (protocols[i].name, auth->name, (int) auth->name_length) == 0)
	    {
		++count;
		(*protocols[i].Add) (auth->data_length, auth->data,
					 ++AuthorizationIndex);
	    }
	}
	XauDisposeAuth (auth);
    }
    fclose (f);
    return count;
}

#ifdef XDMCP
/*
 * XdmcpInit calls this function to discover all authorization
 * schemes supported by the display
 */
void
RegisterAuthorizations ()
{
    int	    i;

    for (i = 0; i < NUM_AUTHORIZATION; i++)
	XdmcpRegisterAuthorization (protocols[i].name,
				    (int)protocols[i].name_length);
}
#endif

XID
CheckAuthorization (name_length, name, data_length, data, client, reason)
    unsigned int	name_length;
    char	*name;
    unsigned int	data_length;
    char	*data;
    ClientPtr client;
    char	**reason;	/* failure message.  NULL for default msg */
{
    int	i;
    struct stat buf;
    static time_t lastmod = 0;

    if (!authorization_file || stat(authorization_file, &buf))
    {
	lastmod = 0;
	ShouldLoadAuth = TRUE;	/* stat lost, so force reload */
    }
    else if (buf.st_mtime > lastmod)
    {
	lastmod = buf.st_mtime;
	ShouldLoadAuth = TRUE;
    }
    if (ShouldLoadAuth)
    {
	if (LoadAuthorization())
	    DisableLocalHost(); /* got at least one */
	else
	    EnableLocalHost ();
    }
    if (name_length)
	for (i = 0; i < NUM_AUTHORIZATION; i++) {
	    if (protocols[i].name_length == name_length &&
		memcmp (protocols[i].name, name, (int) name_length) == 0)
	    {
		return (*protocols[i].Check) (data_length, data, client, reason);
	    }
	}
    return (XID) ~0L;
}

void
ResetAuthorization ()
{
    int	i;

    for (i = 0; i < NUM_AUTHORIZATION; i++)
	(*protocols[i].Reset)();
    ShouldLoadAuth = TRUE;
}

XID
AuthorizationToID (name_length, name, data_length, data)
unsigned short	name_length;
char	*name;
unsigned short	data_length;
char	*data;
{
    int	i;

    for (i = 0; i < NUM_AUTHORIZATION; i++) {
    	if (protocols[i].name_length == name_length &&
	    memcmp (protocols[i].name, name, (int) name_length) == 0)
    	{
	    return (*protocols[i].ToID) (data_length, data);
    	}
    }
    return (XID) ~0L;
}

int
AuthorizationFromID (id, name_lenp, namep, data_lenp, datap)
XID id;
unsigned short	*name_lenp;
char	**namep;
unsigned short	*data_lenp;
char	**datap;
{
    int	i;

    for (i = 0; i < NUM_AUTHORIZATION; i++) {
	if ((*protocols[i].FromID) (id, data_lenp, datap)) {
	    *name_lenp = protocols[i].name_length;
	    *namep = protocols[i].name;
	    return 1;
	}
    }
    return 0;
}

int
RemoveAuthorization (name_length, name, data_length, data)
unsigned short	name_length;
char	*name;
unsigned short	data_length;
char	*data;
{
    int	i;

    for (i = 0; i < NUM_AUTHORIZATION; i++) {
    	if (protocols[i].name_length == name_length &&
	    memcmp (protocols[i].name, name, (int) name_length) == 0)
    	{
	    return (*protocols[i].Remove) (data_length, data);
    	}
    }
    return 0;
}

int
AddAuthorization (name_length, name, data_length, data)
unsigned int	name_length;
char	*name;
unsigned int	data_length;
char	*data;
{
    int	i;

    for (i = 0; i < NUM_AUTHORIZATION; i++) {
    	if (protocols[i].name_length == name_length &&
	    memcmp (protocols[i].name, name, (int) name_length) == 0)
    	{
	    return (*protocols[i].Add) (data_length, data,
					++AuthorizationIndex);
    	}
    }
    return 0;
}