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/* Copyright (C) 2001-2004 Bart Massey and Jamey Sharp.
*
* 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
* AUTHORS 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 names of the authors or their
* institutions 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 authors.
*/
/* Authorization systems for the X protocol. */
#include <assert.h>
#include <X11/Xauth.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <sys/un.h>
#include <sys/param.h>
#include <unistd.h>
#include <stdlib.h>
#include "xcb.h"
#include "xcbint.h"
#ifdef HASXDMAUTH
#include <X11/Xdmcp.h>
#endif
enum auth_protos {
#ifdef HASXDMAUTH
AUTH_XA1,
#endif
AUTH_MC1,
N_AUTH_PROTOS
};
static char *authnames[N_AUTH_PROTOS] = {
#ifdef HASXDMAUTH
"XDM-AUTHORIZATION-1",
#endif
"MIT-MAGIC-COOKIE-1",
};
static size_t memdup(char **dst, void *src, size_t len)
{
if(len)
*dst = malloc(len);
else
*dst = 0;
if(!*dst)
return 0;
memcpy(*dst, src, len);
return len;
}
static int authname_match(enum auth_protos kind, char *name, int namelen)
{
if(strlen(authnames[kind]) != namelen)
return 0;
if(memcmp(authnames[kind], name, namelen))
return 0;
return 1;
}
static Xauth *get_authptr(struct sockaddr *sockname, unsigned int socknamelen,
int display)
{
char *addr = 0;
int addrlen = 0;
unsigned short family;
char hostnamebuf[256]; /* big enough for max hostname */
char dispbuf[40]; /* big enough to hold more than 2^64 base 10 */
int authnamelens[N_AUTH_PROTOS];
int i;
family = FamilyLocal; /* 256 */
switch(sockname->sa_family)
{
case AF_INET6:
addr = (char *) &((struct sockaddr_in6 *)sockname)->sin6_addr;
addrlen = sizeof(((struct sockaddr_in6 *)sockname)->sin6_addr);
if(!IN6_IS_ADDR_V4MAPPED(addr))
{
if(!IN6_IS_ADDR_LOOPBACK(addr))
family = XCB_FAMILY_INTERNET_6;
break;
}
addr += 12;
/* if v4-mapped, fall through. */
case AF_INET:
if(!addr)
addr = (char *) &((struct sockaddr_in *)sockname)->sin_addr;
addrlen = sizeof(((struct sockaddr_in *)sockname)->sin_addr);
if(*(in_addr_t *) addr != htonl(INADDR_LOOPBACK))
family = XCB_FAMILY_INTERNET;
break;
case AF_UNIX:
break;
default:
return 0; /* cannot authenticate this family */
}
snprintf(dispbuf, sizeof(dispbuf), "%d", display);
if (family == FamilyLocal) {
if (gethostname(hostnamebuf, sizeof(hostnamebuf)) == -1)
return 0; /* do not know own hostname */
addr = hostnamebuf;
addrlen = strlen(addr);
}
for (i = 0; i < N_AUTH_PROTOS; i++)
authnamelens[i] = strlen(authnames[i]);
return XauGetBestAuthByAddr (family,
(unsigned short) addrlen, addr,
(unsigned short) strlen(dispbuf), dispbuf,
N_AUTH_PROTOS, authnames, authnamelens);
}
#ifdef HASXDMAUTH
static int next_nonce(void)
{
static int nonce = 0;
static pthread_mutex_t nonce_mutex = PTHREAD_MUTEX_INITIALIZER;
int ret;
pthread_mutex_lock(&nonce_mutex);
ret = nonce++;
pthread_mutex_unlock(&nonce_mutex);
return ret;
}
static void do_append(char *buf, int *idxp, void *val, size_t valsize) {
memcpy(buf + *idxp, val, valsize);
*idxp += valsize;
}
#endif
static int compute_auth(xcb_auth_info_t *info, Xauth *authptr, struct sockaddr *sockname)
{
if (authname_match(AUTH_MC1, authptr->name, authptr->name_length)) {
info->datalen = memdup(&info->data, authptr->data, authptr->data_length);
if(!info->datalen)
return 0;
return 1;
}
#ifdef HASXDMAUTH
#define APPEND(buf,idx,val) do_append((buf),&(idx),&(val),sizeof(val))
if (authname_match(AUTH_XA1, authptr->name, authptr->name_length)) {
int j;
info->data = malloc(192 / 8);
if(!info->data)
return 0;
for (j = 0; j < 8; j++)
info->data[j] = authptr->data[j];
switch(sockname->sa_family) {
case AF_INET:
/*block*/ {
struct sockaddr_in *si = (struct sockaddr_in *) sockname;
APPEND(info->data, j, si->sin_addr.s_addr);
APPEND(info->data, j, si->sin_port);
}
break;
case AF_UNIX:
/*block*/ {
long fakeaddr = htonl(0xffffffff - next_nonce());
short fakeport = htons(getpid());
APPEND(info->data, j, fakeaddr);
APPEND(info->data, j, fakeport);
}
break;
default:
free(info->data);
return 0; /* do not know how to build this */
}
{
long now;
time(&now);
now = htonl(now);
APPEND(info->data, j, now);
}
assert(j <= 192 / 8);
while (j < 192 / 8)
info->data[j++] = 0;
info->datalen = j;
XdmcpWrap ((unsigned char *) info->data, (unsigned char *) authptr->data + 8, (unsigned char *) info->data, info->datalen);
return 1;
}
#undef APPEND
#endif
return 0; /* Unknown authorization type */
}
int _xcb_get_auth_info(int fd, xcb_auth_info_t *info, int display)
{
/* code adapted from Xlib/ConnDis.c, xtrans/Xtranssocket.c,
xtrans/Xtransutils.c */
char sockbuf[sizeof(struct sockaddr) + MAXPATHLEN];
unsigned int socknamelen = sizeof(sockbuf); /* need extra space */
struct sockaddr *sockname = (struct sockaddr *) &sockbuf;
Xauth *authptr = 0;
int ret = 1;
if (getpeername(fd, sockname, &socknamelen) == -1)
return 0; /* can only authenticate sockets */
authptr = get_authptr(sockname, socknamelen, display);
if (authptr == 0)
return 0; /* cannot find good auth data */
info->namelen = memdup(&info->name, authptr->name, authptr->name_length);
if(info->namelen)
ret = compute_auth(info, authptr, sockname);
if(!ret)
{
free(info->name);
info->name = 0;
info->namelen = 0;
}
XauDisposeAuth(authptr);
return ret;
}
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