1 files changed, 125 insertions, 0 deletions

diff --git a/src/jailcheck/virtual.c b/src/jailcheck/virtual.c
new file mode 100644
index 000000000..09092f9ce
--- /dev/null
+++ b/src/jailcheck/virtual.c
@@ -0,0 +1,125 @@
+/*
+ * Copyright (C) 2014-2021 Firejail Authors
+ *
+ * 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 "jailcheck.h"
+#include <dirent.h>
+#include <sys/wait.h>
+
+
+#define MAX_TEST_FILES 16
+static char *dirs[MAX_TEST_FILES];
+static char *files[MAX_TEST_FILES];
+static int files_cnt = 0;
+
+void virtual_setup(const char *directory) {
+        // I am root!
+        assert(directory);
+        assert(*directory == '/');
+        assert(files_cnt < MAX_TEST_FILES);
+
+        // try to open the dir as root
+        DIR *dir = opendir(directory);
+        if (!dir) {
+                fprintf(stderr, "Warning: directory %s not found, skipping\n", directory);
+                return;
+        }
+        closedir(dir);
+
+        // create a test file
+        char *test_file;
+        if (asprintf(&test_file, "%s/jailcheck-private-%d", directory, getpid()) == -1)
+                errExit("asprintf");
+
+        FILE *fp = fopen(test_file, "w");
+        if (!fp) {
+                printf("Warning: I cannot create test file in directory %s, skipping...\n", directory);
+                return;
+        }
+        fprintf(fp, "this file was created by firetest utility, you can safely delete it\n");
+        fclose(fp);
+        if (strcmp(directory, user_home_dir) == 0) {
+                int rv = chown(test_file, user_uid, user_gid);
+                if (rv)
+                        errExit("chown");
+        }
+
+        char *dname = strdup(directory);
+        if (!dname)
+                errExit("strdup");
+        dirs[files_cnt] = dname;
+        files[files_cnt] = test_file;
+        files_cnt++;
+}
+
+void virtual_destroy(void) {
+        // remove test files
+        int i;
+
+        for (i = 0; i < files_cnt; i++) {
+                int rv = unlink(files[i]);
+                (void) rv;
+        }
+        files_cnt = 0;
+}
+
+void virtual_test(void) {
+        // I am root in sandbox mount namespace
+        assert(user_uid);
+        int i;
+
+        int cnt = 0;
+        cnt += printf("   Virtual dirs: "); fflush(0);
+
+        for (i = 0; i < files_cnt; i++) {
+                assert(files[i]);
+
+                // I am root!
+                pid_t child = fork();
+                if (child == -1)
+                        errExit("fork");
+
+                if (child == 0) { // child
+                        // drop privileges
+                        if (setgid(user_gid) != 0)
+                                errExit("setgid");
+                        if (setuid(user_uid) != 0)
+                                errExit("setuid");
+
+                        // try to open the file for reading
+                        FILE *fp = fopen(files[i], "r");
+                        if (fp)
+                                fclose(fp);
+                        else {
+                                if (cnt == 0)
+                                        cnt += printf("\n                 ");
+                                cnt += printf("%s, ", dirs[i]);
+                                if (cnt > 60)
+                                        cnt = 0;
+                        }
+                        fflush(0);
+                        exit(cnt);
+                }
+
+                // wait for the child to finish
+                int status;
+                wait(&status);
+                cnt = WEXITSTATUS(status);
+        }
+        printf("\n");
+}