1 files changed, 76 insertions, 0 deletions

diff --git a/src/firejail/fs_trace.c b/src/firejail/fs_trace.c
new file mode 100644
index 000000000..1c7ef5cbe
--- /dev/null
+++ b/src/firejail/fs_trace.c
@@ -0,0 +1,76 @@
+/*
+ * Copyright (C) 2014, 2015 netblue30 (netblue30@yahoo.com)
+ *
+ * This file is part of firejail project
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+*/
+#include "firejail.h"
+#include <sys/mount.h>
+#include <sys/stat.h>
+#include <linux/limits.h>
+#include <glob.h>
+#include <dirent.h>
+#include <fcntl.h>
+#include <pwd.h>
+
+void fs_trace_preload(void) {
+        struct stat s;
+
+        // create an empty /etc/ld.so.preload
+        if (stat("/etc/ld.so.preload", &s)) {
+                if (arg_debug)
+                        printf("Creating an empty /etc/ld.so.preload file\n");
+                /* coverity[toctou] */
+                FILE *fp = fopen("/etc/ld.so.preload", "w");
+                if (!fp)
+                        errExit("fopen");
+                fclose(fp);
+                if (chown("/etc/ld.so.preload", 0, 0) < 0)
+                        errExit("chown");
+                if (chmod("/etc/ld.so.preload", S_IRUSR | S_IWRITE | S_IRGRP | S_IROTH ) < 0)
+                        errExit("chmod");
+        }
+}
+
+void fs_trace(void) {
+        // create /tmp/firejail/mnt directory
+        fs_build_mnt_dir();
+        
+        // create the new ld.so.preload file and mount-bind it
+        if (arg_debug)
+                printf("Create the new ld.so.preload file\n");
+        char *preload;
+        if (asprintf(&preload, "%s/ld.so.preload", MNT_DIR) == -1)
+                errExit("asprintf");
+        FILE *fp = fopen(preload, "w");
+        if (!fp)
+                errExit("fopen");
+        fprintf(fp, "%s/lib/firejail/libtrace.so\n", PREFIX);
+        fclose(fp);
+        if (chown(preload, 0, 0) < 0)
+                errExit("chown");
+        if (chmod(preload, S_IRUSR | S_IWRITE | S_IRGRP | S_IROTH ) < 0)
+                errExit("chmod");
+        
+        // mount the new preload file
+        if (arg_debug)
+                printf("Mount the new ld.so.preload file\n");
+        if (mount(preload, "/etc/ld.so.preload", NULL, MS_BIND|MS_REC, NULL) < 0)
+                errExit("mount bind ls.so.preload");
+}
+
+                
+        
\ No newline at end of file