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authormarha <marha@users.sourceforge.net>2011-03-25 10:41:05 +0000
committermarha <marha@users.sourceforge.net>2011-03-25 10:41:05 +0000
commit272e57235cd60a2e65ac8258d96a02eb3939b687 (patch)
tree789d74bd6ec1cc468f1f81aab97d4e4dfdb2d5c5 /libxcb/src
parentb39f063f74bf0163eaf34db03134f226d18142ec (diff)
downloadvcxsrv-272e57235cd60a2e65ac8258d96a02eb3939b687.tar.gz
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vcxsrv-272e57235cd60a2e65ac8258d96a02eb3939b687.zip
git update until 25 Mar 2011
xserver fontconfig glproto libXau libXft libXmu libfontenc libxcb mesa mkfontscale pixman randrproto xkeyboard-config xtrans xwininfo updated following packages: xproto-7.0.21 xineramaproto-1.2.1 libXt-1.1.1 libxkbfile-1.0.7 libXpm-3.5.9 libXfont-1.4.3 libXaw-1.0.9 bdftopcf-1.0.3 encodings-1.0.4 fixesproto-5.0 font-adobe-100dpi-1.0.3 font-adobe-75dpi-1.0.3 font-adobe-utopia-100dpi-1.0.4 font-adobe-utopia-75dpi-1.0.4 font-adobe-utopia-type1-1.0.4 font-alias-1.0.3 font-arabic-misc-1.0.3 font-bh-100dpi-1.0.3 font-bh-75dpi-1.0.3 font-bh-lucidatypewriter-100dpi-1.0.3 font-bh-lucidatypewriter-75dpi-1.0.3 font-bh-ttf-1.0.3 font-bh-type1-1.0.3 font-bitstream-100dpi-1.0.3 font-bitstream-75dpi-1.0.3 font-bitstream-speedo-1.0.2 font-bitstream-type1-1.0.3 font-cronyx-cyrillic-1.0.3 font-cursor-misc-1.0.3 font-daewoo-misc-1.0.3 font-dec-misc-1.0.3 font-ibm-type1-1.0.3 font-isas-misc-1.0.3 font-jis-misc-1.0.3 font-micro-misc-1.0.3 font-misc-cyrillic-1.0.3 font-misc-ethiopic-1.0.3 font-misc-meltho-1.0.3 font-misc-misc-1.1.2 font-mutt-misc-1.0.3 font-schumacher-misc-1.1.2 font-screen-cyrillic-1.0.4 font-sony-misc-1.0.3 font-sun-misc-1.0.3 font-util-1.2.0 font-winitzki-cyrillic-1.0.3 font-xfree86-type1-1.0.4
Diffstat (limited to 'libxcb/src')
-rw-r--r--libxcb/src/xcb_auth.c725
1 files changed, 364 insertions, 361 deletions
diff --git a/libxcb/src/xcb_auth.c b/libxcb/src/xcb_auth.c
index 967ba283a..a3a7e45b5 100644
--- a/libxcb/src/xcb_auth.c
+++ b/libxcb/src/xcb_auth.c
@@ -1,361 +1,364 @@
-/* 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/param.h>
-#include <unistd.h>
-#include <stdlib.h>
-
-#ifdef _WIN32
-#include "xcb_windefs.h"
-#else
-#include <sys/socket.h>
-#include <netinet/in.h>
-#include <sys/un.h>
-#endif /* _WIN32 */
-
-#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
-};
-
-#define AUTH_PROTO_XDM_AUTHORIZATION "XDM-AUTHORIZATION-1"
-#define AUTH_PROTO_MIT_MAGIC_COOKIE "MIT-MAGIC-COOKIE-1"
-
-static char *authnames[N_AUTH_PROTOS] = {
-#ifdef HASXDMAUTH
- AUTH_PROTO_XDM_AUTHORIZATION,
-#endif
- AUTH_PROTO_MIT_MAGIC_COOKIE,
-};
-
-static int authnameslen[N_AUTH_PROTOS] = {
-#ifdef HASXDMAUTH
- sizeof(AUTH_PROTO_XDM_AUTHORIZATION) - 1,
-#endif
- sizeof(AUTH_PROTO_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, size_t namelen)
-{
- if(authnameslen[kind] != namelen)
- return 0;
- if(memcmp(authnames[kind], name, namelen))
- return 0;
- return 1;
-}
-
-#define SIN6_ADDR(s) (&((struct sockaddr_in6 *)s)->sin6_addr)
-
-static Xauth *get_authptr(struct sockaddr *sockname, 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 dispbuflen;
-
- family = FamilyLocal; /* 256 */
- switch(sockname->sa_family)
- {
-#ifdef AF_INET6
- case AF_INET6:
- addr = (char *) SIN6_ADDR(sockname);
- addrlen = sizeof(*SIN6_ADDR(sockname));
- if(!IN6_IS_ADDR_V4MAPPED(SIN6_ADDR(sockname)))
- {
- if(!IN6_IS_ADDR_LOOPBACK(SIN6_ADDR(sockname)))
- family = XCB_FAMILY_INTERNET_6;
- break;
- }
- addr += 12;
- /* if v4-mapped, fall through. */
-#endif
- 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 */
- }
-
- dispbuflen = snprintf(dispbuf, sizeof(dispbuf), "%d", display);
- if(dispbuflen < 0)
- return 0;
- /* snprintf may have truncate our text */
- dispbuflen = MIN(dispbuflen, sizeof(dispbuf) - 1);
-
- if (family == FamilyLocal) {
- if (gethostname(hostnamebuf, sizeof(hostnamebuf)) == -1)
- return 0; /* do not know own hostname */
- addr = hostnamebuf;
- addrlen = strlen(addr);
- }
-
- return XauGetBestAuthByAddr (family,
- (unsigned short) addrlen, addr,
- (unsigned short) dispbuflen, dispbuf,
- N_AUTH_PROTOS, authnames, authnameslen);
-}
-
-#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;
-#ifdef AF_INET6
- case AF_INET6:
- /*block*/ {
- struct sockaddr_in6 *si6 = (struct sockaddr_in6 *) sockname;
- if(IN6_IS_ADDR_V4MAPPED(SIN6_ADDR(sockname)))
- {
- do_append(info->data, &j, &si6->sin6_addr.s6_addr[12], 4);
- APPEND(info->data, j, si6->sin6_port);
- }
- else
- {
- /* XDM-AUTHORIZATION-1 does not handle IPv6 correctly. Do the
- same thing Xlib does: use all zeroes for the 4-byte address
- and 2-byte port number. */
- uint32_t fakeaddr = 0;
- uint16_t fakeport = 0;
- APPEND(info->data, j, fakeaddr);
- APPEND(info->data, j, fakeport);
- }
- }
- break;
-#endif
- case AF_UNIX:
- /*block*/ {
- uint32_t fakeaddr = htonl(0xffffffff - next_nonce());
- uint16_t 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 */
- }
- {
- uint32_t now = htonl(time(0));
- 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 */
-}
-
-/* `sockaddr_un.sun_path' typical size usually ranges between 92 and 108 */
-#define INITIAL_SOCKNAME_SLACK 108
-
-/* Return a dynamically allocated socket address structure according
- to the value returned by either getpeername() or getsockname()
- (according to POSIX, applications should not assume a particular
- length for `sockaddr_un.sun_path') */
-static struct sockaddr *get_peer_sock_name(int (*socket_func)(int,
- struct sockaddr *,
- socklen_t *),
- int fd)
-{
- socklen_t socknamelen = sizeof(struct sockaddr) + INITIAL_SOCKNAME_SLACK;
- socklen_t actual_socknamelen = socknamelen;
- struct sockaddr *sockname = malloc(socknamelen), *new_sockname = NULL;
-
- if (sockname == NULL)
- return NULL;
-
- /* Both getpeername() and getsockname() truncates sockname if
- there is not enough space and set the required length in
- actual_socknamelen */
- if (socket_func(fd, sockname, &actual_socknamelen) == -1)
- goto sock_or_realloc_error;
-
- if (actual_socknamelen > socknamelen)
- {
- socknamelen = actual_socknamelen;
-
- if ((new_sockname = realloc(sockname, actual_socknamelen)) == NULL ||
- socket_func(fd, new_sockname, &actual_socknamelen) == -1 ||
- actual_socknamelen > socknamelen)
- goto sock_or_realloc_error;
-
- sockname = new_sockname;
- }
-
- return sockname;
-
- sock_or_realloc_error:
- free(sockname);
- return NULL;
-}
-
-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 */
- struct sockaddr *sockname = NULL;
- int gotsockname = 0;
- Xauth *authptr = 0;
- int ret = 1;
-
- /* Some systems like hpux or Hurd do not expose peer names
- * for UNIX Domain Sockets, but this is irrelevant,
- * since compute_auth() ignores the peer name in this
- * case anyway.*/
- if ((sockname = get_peer_sock_name(getpeername, fd)) == NULL)
- {
- if ((sockname = get_peer_sock_name(getsockname, fd)) == NULL)
- return 0; /* can only authenticate sockets */
- if (sockname->sa_family != AF_UNIX)
- {
- free(sockname);
- return 0; /* except for AF_UNIX, sockets should have peernames */
- }
- gotsockname = 1;
- }
-
- authptr = get_authptr(sockname, display);
- if (authptr == 0)
- {
- free(sockname);
- return 0; /* cannot find good auth data */
- }
-
- info->namelen = memdup(&info->name, authptr->name, authptr->name_length);
- if (!info->namelen)
- goto no_auth; /* out of memory */
-
- if (!gotsockname)
- {
- free(sockname);
-
- if ((sockname = get_peer_sock_name(getsockname, fd)) == NULL)
- {
- free(info->name);
- goto no_auth; /* can only authenticate sockets */
- }
- }
-
- ret = compute_auth(info, authptr, sockname);
- if(!ret)
- {
- free(info->name);
- goto no_auth; /* cannot build auth record */
- }
-
- free(sockname);
- sockname = NULL;
-
- XauDisposeAuth(authptr);
- return ret;
-
- no_auth:
- free(sockname);
-
- info->name = 0;
- info->namelen = 0;
- XauDisposeAuth(authptr);
- return 0;
-}
+/* 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/param.h>
+#include <unistd.h>
+#include <stdlib.h>
+
+#ifdef _WIN32
+#include "xcb_windefs.h"
+#else
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <sys/un.h>
+#endif /* _WIN32 */
+
+#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
+};
+
+#define AUTH_PROTO_XDM_AUTHORIZATION "XDM-AUTHORIZATION-1"
+#define AUTH_PROTO_MIT_MAGIC_COOKIE "MIT-MAGIC-COOKIE-1"
+
+static char *authnames[N_AUTH_PROTOS] = {
+#ifdef HASXDMAUTH
+ AUTH_PROTO_XDM_AUTHORIZATION,
+#endif
+ AUTH_PROTO_MIT_MAGIC_COOKIE,
+};
+
+static int authnameslen[N_AUTH_PROTOS] = {
+#ifdef HASXDMAUTH
+ sizeof(AUTH_PROTO_XDM_AUTHORIZATION) - 1,
+#endif
+ sizeof(AUTH_PROTO_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, size_t namelen)
+{
+ if(authnameslen[kind] != namelen)
+ return 0;
+ if(memcmp(authnames[kind], name, namelen))
+ return 0;
+ return 1;
+}
+
+#define SIN6_ADDR(s) (&((struct sockaddr_in6 *)s)->sin6_addr)
+
+static Xauth *get_authptr(struct sockaddr *sockname, 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 dispbuflen;
+
+ family = FamilyLocal; /* 256 */
+ switch(sockname->sa_family)
+ {
+#ifdef AF_INET6
+ case AF_INET6:
+ addr = (char *) SIN6_ADDR(sockname);
+ addrlen = sizeof(*SIN6_ADDR(sockname));
+ if(!IN6_IS_ADDR_V4MAPPED(SIN6_ADDR(sockname)))
+ {
+ if(!IN6_IS_ADDR_LOOPBACK(SIN6_ADDR(sockname)))
+ family = XCB_FAMILY_INTERNET_6;
+ break;
+ }
+ addr += 12;
+ /* if v4-mapped, fall through. */
+#endif
+ 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 */
+ }
+
+ dispbuflen = snprintf(dispbuf, sizeof(dispbuf), "%d", display);
+ if(dispbuflen < 0)
+ return 0;
+ /* snprintf may have truncate our text */
+ dispbuflen = MIN(dispbuflen, sizeof(dispbuf) - 1);
+
+ if (family == FamilyLocal) {
+ if (gethostname(hostnamebuf, sizeof(hostnamebuf)) == -1)
+ return 0; /* do not know own hostname */
+ addr = hostnamebuf;
+ addrlen = strlen(addr);
+ }
+
+ return XauGetBestAuthByAddr (family,
+ (unsigned short) addrlen, addr,
+ (unsigned short) dispbuflen, dispbuf,
+ N_AUTH_PROTOS, authnames, authnameslen);
+}
+
+#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;
+#ifdef AF_INET6
+ case AF_INET6:
+ /*block*/ {
+ struct sockaddr_in6 *si6 = (struct sockaddr_in6 *) sockname;
+ if(IN6_IS_ADDR_V4MAPPED(SIN6_ADDR(sockname)))
+ {
+ do_append(info->data, &j, &si6->sin6_addr.s6_addr[12], 4);
+ APPEND(info->data, j, si6->sin6_port);
+ }
+ else
+ {
+ /* XDM-AUTHORIZATION-1 does not handle IPv6 correctly. Do the
+ same thing Xlib does: use all zeroes for the 4-byte address
+ and 2-byte port number. */
+ uint32_t fakeaddr = 0;
+ uint16_t fakeport = 0;
+ APPEND(info->data, j, fakeaddr);
+ APPEND(info->data, j, fakeport);
+ }
+ }
+ break;
+#endif
+ case AF_UNIX:
+ /*block*/ {
+ uint32_t fakeaddr = htonl(0xffffffff - next_nonce());
+ uint16_t 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 */
+ }
+ {
+ uint32_t now = htonl(time(0));
+ 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 */
+}
+
+/* `sockaddr_un.sun_path' typical size usually ranges between 92 and 108 */
+#define INITIAL_SOCKNAME_SLACK 108
+
+/* Return a dynamically allocated socket address structure according
+ to the value returned by either getpeername() or getsockname()
+ (according to POSIX, applications should not assume a particular
+ length for `sockaddr_un.sun_path') */
+static struct sockaddr *get_peer_sock_name(int (*socket_func)(int,
+ struct sockaddr *,
+ socklen_t *),
+ int fd)
+{
+ socklen_t socknamelen = sizeof(struct sockaddr) + INITIAL_SOCKNAME_SLACK;
+ socklen_t actual_socknamelen = socknamelen;
+ struct sockaddr *sockname = malloc(socknamelen);
+
+ if (sockname == NULL)
+ return NULL;
+
+ /* Both getpeername() and getsockname() truncates sockname if
+ there is not enough space and set the required length in
+ actual_socknamelen */
+ if (socket_func(fd, sockname, &actual_socknamelen) == -1)
+ goto sock_or_realloc_error;
+
+ if (actual_socknamelen > socknamelen)
+ {
+ struct sockaddr *new_sockname = NULL;
+ socknamelen = actual_socknamelen;
+
+ if ((new_sockname = realloc(sockname, actual_socknamelen)) == NULL)
+ goto sock_or_realloc_error;
+
+ sockname = new_sockname;
+
+ if (socket_func(fd, sockname, &actual_socknamelen) == -1 ||
+ actual_socknamelen > socknamelen)
+ goto sock_or_realloc_error;
+ }
+
+ return sockname;
+
+ sock_or_realloc_error:
+ free(sockname);
+ return NULL;
+}
+
+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 */
+ struct sockaddr *sockname = NULL;
+ int gotsockname = 0;
+ Xauth *authptr = 0;
+ int ret = 1;
+
+ /* Some systems like hpux or Hurd do not expose peer names
+ * for UNIX Domain Sockets, but this is irrelevant,
+ * since compute_auth() ignores the peer name in this
+ * case anyway.*/
+ if ((sockname = get_peer_sock_name(getpeername, fd)) == NULL)
+ {
+ if ((sockname = get_peer_sock_name(getsockname, fd)) == NULL)
+ return 0; /* can only authenticate sockets */
+ if (sockname->sa_family != AF_UNIX)
+ {
+ free(sockname);
+ return 0; /* except for AF_UNIX, sockets should have peernames */
+ }
+ gotsockname = 1;
+ }
+
+ authptr = get_authptr(sockname, display);
+ if (authptr == 0)
+ {
+ free(sockname);
+ return 0; /* cannot find good auth data */
+ }
+
+ info->namelen = memdup(&info->name, authptr->name, authptr->name_length);
+ if (!info->namelen)
+ goto no_auth; /* out of memory */
+
+ if (!gotsockname)
+ {
+ free(sockname);
+
+ if ((sockname = get_peer_sock_name(getsockname, fd)) == NULL)
+ {
+ free(info->name);
+ goto no_auth; /* can only authenticate sockets */
+ }
+ }
+
+ ret = compute_auth(info, authptr, sockname);
+ if(!ret)
+ {
+ free(info->name);
+ goto no_auth; /* cannot build auth record */
+ }
+
+ free(sockname);
+ sockname = NULL;
+
+ XauDisposeAuth(authptr);
+ return ret;
+
+ no_auth:
+ free(sockname);
+
+ info->name = 0;
+ info->namelen = 0;
+ XauDisposeAuth(authptr);
+ return 0;
+}