Support reading ucred from the socket on FreeBSD

On FreeBSD we have to use getsockopt(fd, SOL_LOCAL, LOCAL_PEERCRED)
instead. This change is based on a downstream patch in FreeBSD ports.

Co-authored-by: Greg V <greg@unrelenting.technology>
Co-authored-by: Koop Mast <kwm@rainbow-runner.nl>
Signed-off-by: Alex Richardson <Alexander.Richardson@cl.cam.ac.uk>

diff --git a/meson.build b/meson.build
index 427aacf..aeb171e 100644 (file)
--- a/meson.build
+++ b/meson.build
@@ -26,7 +26,7 @@ add_project_arguments(
        language: 'c'
 )
 
-foreach h: [ 'sys/prctl.h' ]
+foreach h: [ 'sys/prctl.h', 'sys/ucred.h' ]
        config_h.set('HAVE_' + h.underscorify().to_upper(), cc.has_header(h))
 endforeach
 
@@ -41,6 +41,7 @@ have_funcs = [
 foreach f: have_funcs
        config_h.set('HAVE_' + f.underscorify().to_upper(), cc.has_function(f))
 endforeach
+config_h.set10('HAVE_XUCRED_CR_PID', cc.has_member('struct xucred', 'cr_pid', prefix : '#include <sys/ucred.h>'))
 
 if get_option('libraries')
        if host_machine.system() == 'freebsd'

diff --git a/src/wayland-os.c b/src/wayland-os.c
index 1e4a23d..46db267 100644 (file)
--- a/src/wayland-os.c
+++ b/src/wayland-os.c
@@ -25,14 +25,19 @@
 
 #define _GNU_SOURCE
 
+#include "../config.h"
+
 #include <sys/types.h>
 #include <sys/socket.h>
 #include <unistd.h>
 #include <fcntl.h>
 #include <errno.h>
 #include <sys/epoll.h>
+#include <sys/un.h>
+#ifdef HAVE_SYS_UCRED_H
+#include <sys/ucred.h>
+#endif
 
-#include "../config.h"
 #include "wayland-os.h"
 
 static int
@@ -72,6 +77,46 @@ wl_os_socket_cloexec(int domain, int type, int protocol)
        return set_cloexec_or_close(fd);
 }
 
+#if defined(__FreeBSD__)
+int
+wl_os_socket_peercred(int sockfd, uid_t *uid, gid_t *gid, pid_t *pid)
+{
+       socklen_t len;
+       struct xucred ucred;
+
+       len = sizeof(ucred);
+       if (getsockopt(sockfd, SOL_LOCAL, LOCAL_PEERCRED, &ucred, &len) < 0 ||
+           ucred.cr_version != XUCRED_VERSION)
+               return -1;
+       *uid = ucred.cr_uid;
+       *gid = ucred.cr_gid;
+#if HAVE_XUCRED_CR_PID
+       /* Since https://cgit.freebsd.org/src/commit/?id=c5afec6e895a */
+       *pid = ucred.cr_pid;
+#else
+       *pid = 0;
+#endif
+       return 0;
+}
+#elif defined(SO_PEERCRED)
+int
+wl_os_socket_peercred(int sockfd, uid_t *uid, gid_t *gid, pid_t *pid)
+{
+       socklen_t len;
+       struct ucred ucred;
+
+       len = sizeof(ucred);
+       if (getsockopt(sockfd, SOL_SOCKET, SO_PEERCRED, &ucred, &len) < 0)
+               return -1;
+       *uid = ucred.uid;
+       *gid = ucred.gid;
+       *pid = ucred.pid;
+       return 0;
+}
+#else
+#error "Don't know how to read ucred on this platform"
+#endif
+
 int
 wl_os_dupfd_cloexec(int fd, int minfd)
 {

diff --git a/src/wayland-os.h b/src/wayland-os.h
index af37640..ccd76ba 100644 (file)
--- a/src/wayland-os.h
+++ b/src/wayland-os.h
@@ -26,10 +26,16 @@
 #ifndef WAYLAND_OS_H
 #define WAYLAND_OS_H
 
+#include <sys/types.h>
+#include <sys/socket.h>
+
 int
 wl_os_socket_cloexec(int domain, int type, int protocol);
 
 int
+wl_os_socket_peercred(int sockfd, uid_t *uid, gid_t *gid, pid_t *pid);
+
+int
 wl_os_dupfd_cloexec(int fd, int minfd);
 
 ssize_t

diff --git a/src/wayland-server.c b/src/wayland-server.c
index 4783ab3..4778d85 100644 (file)
--- a/src/wayland-server.c
+++ b/src/wayland-server.c
@@ -78,7 +78,9 @@ struct wl_client {
        struct wl_list link;
        struct wl_map objects;
        struct wl_priv_signal destroy_signal;
-       struct ucred ucred;
+       pid_t pid;
+       uid_t uid;
+       gid_t gid;
        int error;
        struct wl_priv_signal resource_created_signal;
 };
@@ -314,7 +316,7 @@ wl_resource_post_error(struct wl_resource *resource,
 static void
 destroy_client_with_error(struct wl_client *client, const char *reason)
 {
-       wl_log("%s (pid %u)\n", reason, client->ucred.pid);
+       wl_log("%s (pid %u)\n", reason, client->pid);
        wl_client_destroy(client);
 }
 
@@ -513,7 +515,6 @@ WL_EXPORT struct wl_client *
 wl_client_create(struct wl_display *display, int fd)
 {
        struct wl_client *client;
-       socklen_t len;
 
        client = zalloc(sizeof *client);
        if (client == NULL)
@@ -528,9 +529,8 @@ wl_client_create(struct wl_display *display, int fd)
        if (!client->source)
                goto err_client;
 
-       len = sizeof client->ucred;
-       if (getsockopt(fd, SOL_SOCKET, SO_PEERCRED,
-                      &client->ucred, &len) < 0)
+       if (wl_os_socket_peercred(fd, &client->uid, &client->gid,
+                                 &client->pid) != 0)
                goto err_source;
 
        client->connection = wl_connection_create(fd);
@@ -586,11 +586,11 @@ wl_client_get_credentials(struct wl_client *client,
                          pid_t *pid, uid_t *uid, gid_t *gid)
 {
        if (pid)
-               *pid = client->ucred.pid;
+               *pid = client->pid;
        if (uid)
-               *uid = client->ucred.uid;
+               *uid = client->uid;
        if (gid)
-               *gid = client->ucred.gid;
+               *gid = client->gid;
 }
 
 /** Get the file descriptor for the client