1 /* Copyright (C) 2001-2004 Bart Massey and Jamey Sharp.
3 * Permission is hereby granted, free of charge, to any person obtaining a
4 * copy of this software and associated documentation files (the "Software"),
5 * to deal in the Software without restriction, including without limitation
6 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
7 * and/or sell copies of the Software, and to permit persons to whom the
8 * Software is furnished to do so, subject to the following conditions:
10 * The above copyright notice and this permission notice shall be included in
11 * all copies or substantial portions of the Software.
13 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
14 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
15 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
16 * AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
17 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
18 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
20 * Except as contained in this notice, the names of the authors or their
21 * institutions shall not be used in advertising or otherwise to promote the
22 * sale, use or other dealings in this Software without prior written
23 * authorization from the authors.
26 /* Authorization systems for the X protocol. */
29 #include <X11/Xauth.h>
30 #include <sys/socket.h>
31 #include <netinet/in.h>
33 #include <sys/param.h>
41 #include <X11/Xdmcp.h>
52 #define AUTH_PROTO_XDM_AUTHORIZATION "XDM-AUTHORIZATION-1"
53 #define AUTH_PROTO_MIT_MAGIC_COOKIE "MIT-MAGIC-COOKIE-1"
55 static char *authnames[N_AUTH_PROTOS] = {
57 AUTH_PROTO_XDM_AUTHORIZATION,
59 AUTH_PROTO_MIT_MAGIC_COOKIE,
62 static int authnameslen[N_AUTH_PROTOS] = {
64 sizeof(AUTH_PROTO_XDM_AUTHORIZATION) - 1,
66 sizeof(AUTH_PROTO_MIT_MAGIC_COOKIE) - 1,
69 static size_t memdup(char **dst, void *src, size_t len)
77 memcpy(*dst, src, len);
81 static int authname_match(enum auth_protos kind, char *name, size_t namelen)
83 if(authnameslen[kind] != namelen)
85 if(memcmp(authnames[kind], name, namelen))
90 #define SIN6_ADDR(s) (&((struct sockaddr_in6 *)s)->sin6_addr)
92 static Xauth *get_authptr(struct sockaddr *sockname, unsigned int socknamelen,
97 unsigned short family;
98 char hostnamebuf[256]; /* big enough for max hostname */
99 char dispbuf[40]; /* big enough to hold more than 2^64 base 10 */
101 family = FamilyLocal; /* 256 */
102 switch(sockname->sa_family)
106 addr = (char *) SIN6_ADDR(sockname);
107 addrlen = sizeof(*SIN6_ADDR(sockname));
108 if(!IN6_IS_ADDR_V4MAPPED(SIN6_ADDR(sockname)))
110 if(!IN6_IS_ADDR_LOOPBACK(SIN6_ADDR(sockname)))
111 family = XCB_FAMILY_INTERNET_6;
115 /* if v4-mapped, fall through. */
119 addr = (char *) &((struct sockaddr_in *)sockname)->sin_addr;
120 addrlen = sizeof(((struct sockaddr_in *)sockname)->sin_addr);
121 if(*(in_addr_t *) addr != htonl(INADDR_LOOPBACK))
122 family = XCB_FAMILY_INTERNET;
127 return 0; /* cannot authenticate this family */
130 snprintf(dispbuf, sizeof(dispbuf), "%d", display);
132 if (family == FamilyLocal) {
133 if (gethostname(hostnamebuf, sizeof(hostnamebuf)) == -1)
134 return 0; /* do not know own hostname */
136 addrlen = strlen(addr);
139 return XauGetBestAuthByAddr (family,
140 (unsigned short) addrlen, addr,
141 (unsigned short) strlen(dispbuf), dispbuf,
142 N_AUTH_PROTOS, authnames, authnameslen);
146 static int next_nonce(void)
148 static int nonce = 0;
149 static pthread_mutex_t nonce_mutex = PTHREAD_MUTEX_INITIALIZER;
151 pthread_mutex_lock(&nonce_mutex);
153 pthread_mutex_unlock(&nonce_mutex);
157 static void do_append(char *buf, int *idxp, void *val, size_t valsize) {
158 memcpy(buf + *idxp, val, valsize);
163 static int compute_auth(xcb_auth_info_t *info, Xauth *authptr, struct sockaddr *sockname)
165 if (authname_match(AUTH_MC1, authptr->name, authptr->name_length)) {
166 info->datalen = memdup(&info->data, authptr->data, authptr->data_length);
172 #define APPEND(buf,idx,val) do_append((buf),&(idx),&(val),sizeof(val))
173 if (authname_match(AUTH_XA1, authptr->name, authptr->name_length)) {
176 info->data = malloc(192 / 8);
180 for (j = 0; j < 8; j++)
181 info->data[j] = authptr->data[j];
182 switch(sockname->sa_family) {
185 struct sockaddr_in *si = (struct sockaddr_in *) sockname;
186 APPEND(info->data, j, si->sin_addr.s_addr);
187 APPEND(info->data, j, si->sin_port);
193 struct sockaddr_in6 *si6 = (struct sockaddr_in6 *) sockname;
194 if(IN6_IS_ADDR_V4MAPPED(SIN6_ADDR(sockname)))
196 do_append(info->data, &j, &si6->sin6_addr.s6_addr[12], 4);
197 APPEND(info->data, j, si6->sin6_port);
201 /* XDM-AUTHORIZATION-1 does not handle IPv6 correctly. Do the
202 same thing Xlib does: use all zeroes for the 4-byte address
203 and 2-byte port number. */
204 uint32_t fakeaddr = 0;
205 uint16_t fakeport = 0;
206 APPEND(info->data, j, fakeaddr);
207 APPEND(info->data, j, fakeport);
214 uint32_t fakeaddr = htonl(0xffffffff - next_nonce());
215 uint16_t fakeport = htons(getpid());
216 APPEND(info->data, j, fakeaddr);
217 APPEND(info->data, j, fakeport);
222 return 0; /* do not know how to build this */
225 uint32_t now = htonl(time(0));
226 APPEND(info->data, j, now);
228 assert(j <= 192 / 8);
232 XdmcpWrap ((unsigned char *) info->data, (unsigned char *) authptr->data + 8, (unsigned char *) info->data, info->datalen);
238 return 0; /* Unknown authorization type */
241 int _xcb_get_auth_info(int fd, xcb_auth_info_t *info, int display)
243 /* code adapted from Xlib/ConnDis.c, xtrans/Xtranssocket.c,
244 xtrans/Xtransutils.c */
245 char sockbuf[sizeof(struct sockaddr) + MAXPATHLEN];
246 unsigned int socknamelen = sizeof(sockbuf); /* need extra space */
247 struct sockaddr *sockname = (struct sockaddr *) &sockbuf;
251 if (getpeername(fd, sockname, &socknamelen) == -1)
253 if (getsockname(fd, sockname, &socknamelen) == -1)
254 return 0; /* can only authenticate sockets */
255 if (sockname->sa_family != AF_UNIX)
257 /* Some systems like hpux or Hurd do not expose peer names
258 * for UNIX Domain Sockets. We do not need it anyway. */
261 authptr = get_authptr(sockname, socknamelen, display);
263 return 0; /* cannot find good auth data */
265 info->namelen = memdup(&info->name, authptr->name, authptr->name_length);
267 ret = compute_auth(info, authptr, sockname);
274 XauDisposeAuth(authptr);