Apple: Added privileged_startx

1 files changed, 250 insertions, 0 deletions

diff --git a/privileged_startx/server.c b/privileged_startx/server.c
new file mode 100644
index 0000000..7afd424
--- /dev/null
+++ b/privileged_startx/server.c
@@ -0,0 +1,250 @@
+/* Copyright (c) 2008 Apple Inc.
+ *
+ * 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 ABOVE LISTED COPYRIGHT
+ * HOLDER(S) 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(s) of the above
+ * copyright holders shall not be used in advertising or otherwise to
+ * promote the sale, use or other dealings in this Software without
+ * prior written authorization.
+ */
+
+#include <mach/mach.h>
+#include <mach/mach_error.h>
+#include <servers/bootstrap.h>
+#include <unistd.h>
+#include <stdio.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fts.h>
+#include <limits.h>
+#include <stdlib.h>
+#include <stdbool.h>
+#include <sys/time.h>
+#include <launch.h>
+#include <asl.h>
+#include <pthread.h>
+#include <errno.h>
+
+#include "privileged_startx.h"
+#include "privileged_startxServer.h"
+
+union MaxMsgSize {
+    union __RequestUnion__privileged_startx_subsystem req;
+    union __ReplyUnion__privileged_startx_subsystem rep; 
+};
+
+/* globals to trigger idle exit */
+#define DEFAULT_IDLE_TIMEOUT 60 /* 60 second timeout, then the server exits */
+
+struct idle_globals {
+	mach_port_t      mp;
+	long    timeout;
+	struct timeval   lastmsg;
+};
+
+struct idle_globals idle_globals;
+
+#ifndef SCRIPTDIR
+#define SCRIPTDIR="/usr/X11/lib/X11/xinit/privileged_startx.d"
+#endif
+
+/* Default script dir */
+const char *script_dir = SCRIPTDIR;
+
+static void* idle_thread(void* param __attribute__((unused)));
+
+int server_main(const char *dir) {
+    mach_msg_size_t mxmsgsz = sizeof(union MaxMsgSize) + MAX_TRAILER_SIZE;
+    mach_port_t mp;
+    kern_return_t kr;
+    long idle_timeout = DEFAULT_IDLE_TIMEOUT;
+
+    launch_data_t config = NULL, checkin = NULL;
+    checkin = launch_data_new_string(LAUNCH_KEY_CHECKIN);
+    config = launch_msg(checkin);
+    if (!config || launch_data_get_type(config) == LAUNCH_DATA_ERRNO) {
+        asl_log(NULL, NULL, ASL_LEVEL_ERR, "launchd checkin failed");
+        exit(EXIT_FAILURE);
+    }
+
+    launch_data_t tmv;
+    tmv = launch_data_dict_lookup(config, LAUNCH_JOBKEY_TIMEOUT);
+    if (tmv) {
+        idle_timeout = launch_data_get_integer(tmv);
+        asl_log(NULL, NULL, ASL_LEVEL_DEBUG,
+                "idle timeout set: %ld seconds", idle_timeout);
+    }
+
+    if(dir) {
+        script_dir = dir;
+        asl_log(NULL, NULL, ASL_LEVEL_DEBUG,
+                "script directory set: %s", script_dir);
+    }
+
+    launch_data_t svc;
+    svc = launch_data_dict_lookup(config, LAUNCH_JOBKEY_MACHSERVICES);
+    if (!svc) {
+        asl_log(NULL, NULL, ASL_LEVEL_ERR, "no mach services");
+        exit(EXIT_FAILURE);
+    }
+
+    svc = launch_data_dict_lookup(svc, BOOTSTRAP_NAME);
+    if (!svc) {
+        asl_log(NULL, NULL, ASL_LEVEL_ERR, "no mach service: %s",
+                BOOTSTRAP_NAME);
+        exit(EXIT_FAILURE);
+    }
+
+    mp = launch_data_get_machport(svc);
+    if (mp == MACH_PORT_NULL) {
+        asl_log(NULL, NULL, ASL_LEVEL_ERR, "NULL mach service: %s",
+                BOOTSTRAP_NAME);
+        exit(EXIT_FAILURE);
+    }
+
+    /* insert a send right so we can send our idle exit message */
+    kr = mach_port_insert_right(mach_task_self(), mp, mp,
+                                MACH_MSG_TYPE_MAKE_SEND);
+    if (kr != KERN_SUCCESS) {
+        asl_log(NULL, NULL, ASL_LEVEL_ERR, "send right failed: %s",
+                mach_error_string(kr));
+        exit(EXIT_FAILURE);
+    }
+
+    /* spawn a thread to monitor our idle timeout */
+    pthread_t thread;
+    idle_globals.mp = mp;
+    idle_globals.timeout = idle_timeout;
+    gettimeofday(&idle_globals.lastmsg, NULL);
+    pthread_create(&thread, NULL, &idle_thread, NULL);
+
+    /* Main event loop */
+    kr = mach_msg_server(privileged_startx_server, mxmsgsz, mp, 0);
+    if (kr != KERN_SUCCESS) {
+        asl_log(NULL, NULL, ASL_LEVEL_ERR,
+                "mach_msg_server(mp): %s\n", mach_error_string(kr));
+        exit(EXIT_FAILURE);
+    }
+
+    exit(EXIT_SUCCESS);
+}
+
+static int ftscmp(const FTSENT **a, const FTSENT **b) {
+    return strcmp((**a).fts_name, (**b).fts_name);
+}
+
+kern_return_t do_privileged_startx(mach_port_t test_port __attribute__((unused))) {
+    kern_return_t retval = KERN_SUCCESS;
+    char fn_buf[PATH_MAX + 1];
+    char *s;
+    int error_code;
+    FTS *ftsp;
+    FTSENT *ftsent;
+
+    const char * path_argv[2] = {script_dir, NULL};
+
+    /* Store that we were called, so the idle timer will reset */
+    gettimeofday(&idle_globals.lastmsg, NULL);
+
+    /* script_dir contains a set of files to run with root privs when X11 starts */
+    ftsp = fts_open(path_argv, FTS_PHYSICAL, ftscmp);
+    if(!ftsp) {
+        asl_log(NULL, NULL, ASL_LEVEL_ERR,
+                "do_privileged_startx: fts_open(%s): %s\n",
+                script_dir, strerror(errno));
+        return KERN_FAILURE;
+    }
+
+    /* Grab our dir */
+    ftsent = fts_read(ftsp);
+    if(!ftsent) {
+        asl_log(NULL, NULL, ASL_LEVEL_ERR,
+                "do_privileged_startx: fts_read(): %s\n", strerror(errno));
+        fts_close(ftsp);
+        return KERN_FAILURE;
+    }
+
+    /* Get a list of the files in this directory */
+    ftsent = fts_children(ftsp, 0);
+    if(!ftsent) {
+        asl_log(NULL, NULL, ASL_LEVEL_ERR,
+                "do_privileged_startx: fts_children(): %s\n", strerror(errno));
+        fts_close(ftsp);
+        return KERN_FAILURE;
+    }
+
+    /* Setup the buffer to have the path to the script dir */
+    strncpy(fn_buf, script_dir, PATH_MAX-1);
+    strcat(fn_buf, "/");
+    s = strrchr(fn_buf, 0);
+
+    /* Itterate over these files in alphabetical order */
+    for(; ftsent; ftsent = ftsent->fts_link) {
+        /* We only source regular files that are executable */
+        /* Note: This assumes we own them, which should always be the case */
+        if((ftsent->fts_statp->st_mode & S_IFREG) &&
+           (ftsent->fts_statp->st_mode & S_IXUSR)) {
+
+            /* Complete the full path filename in fn_buf */
+            strcpy(s, ftsent->fts_name);
+
+            /* Run it */
+            error_code = system(fn_buf);
+            if(error_code != 0) {
+                asl_log(NULL, NULL, ASL_LEVEL_ERR,
+                        "do_privileged_startx: %s: exited with status %d\n",
+                        fn_buf, error_code);
+                retval = KERN_FAILURE;
+            }
+        }
+    }
+
+    fts_close(ftsp);
+    return retval;
+}
+
+kern_return_t do_idle_exit(mach_port_t test_port __attribute__((unused))) {
+    struct timeval now;
+    gettimeofday(&now, NULL);
+
+    long delta = now.tv_sec - idle_globals.lastmsg.tv_sec;
+    if (delta >= idle_globals.timeout) {
+        exit(EXIT_SUCCESS);
+    }
+
+    return KERN_SUCCESS;
+}
+
+static void *idle_thread(void* param __attribute__((unused))) {
+    for(;;) {
+        struct timeval now;
+        gettimeofday(&now, NULL);
+        long delta = (now.tv_sec - idle_globals.lastmsg.tv_sec);
+        if (delta < idle_globals.timeout) {
+            /* sleep for remainder of timeout */
+            sleep(idle_globals.timeout - delta);
+        } else {
+            /* timeout has elapsed, attempt to idle exit */
+            idle_exit(idle_globals.mp);
+        }
+    }
+    return NULL;
+}