static int store_xauthority(void) {
// put a copy of .Xauthority in XAUTHORITY_FILE
fs_build_mnt_dir();
char *src;
char *dest = RUN_XAUTHORITY_FILE;
if (asprintf(&src, "%s/.Xauthority", cfg.homedir) == -1)
errExit("asprintf");
struct stat s;
if (stat(src, &s) == 0) {
if (is_link(src)) {
fprintf(stderr, "Error: invalid .Xauthority file\n");
exit(1);
}
int rv = copy_file(src, dest);
if (rv) {
fprintf(stderr, "Warning: cannot transfer .Xauthority in private home directory\n");
return 0;
}
return 1; // file copied
}
return 0;
}
void fs_private_etc_list(void) {
char *private_list = cfg.etc_private_keep;
assert(private_list);
struct stat s;
if (stat("/etc", &s) == -1) {
fprintf(stderr, "Error: cannot find user /etc directory\n");
exit(1);
}
// create /tmp/firejail/mnt/etc directory
fs_build_mnt_dir();
int rv = mkdir(RUN_ETC_DIR, 0755);
if (rv == -1)
errExit("mkdir");
if (chown(RUN_ETC_DIR, 0, 0) < 0)
errExit("chown");
if (chmod(RUN_ETC_DIR, 0755) < 0)
errExit("chmod");
// copy the list of files in the new etc directory
// using a new child process without root privileges
fs_logger_print(); // save the current log
pid_t child = fork();
if (child < 0)
errExit("fork");
if (child == 0) {
if (arg_debug)
printf("Copying files in the new etc directory:\n");
// elevate privileges - files in the new /etc directory belong to root
if (setreuid(0, 0) < 0)
errExit("setreuid");
if (setregid(0, 0) < 0)
errExit("setregid");
// copy the list of files in the new home directory
char *dlist = strdup(private_list);
if (!dlist)
errExit("strdup");
char *ptr = strtok(dlist, ",");
duplicate(ptr);
while ((ptr = strtok(NULL, ",")) != NULL)
duplicate(ptr);
free(dlist);
fs_logger_print();
exit(0);
}
// wait for the child to finish
waitpid(child, NULL, 0);
if (arg_debug)
printf("Mount-bind %s on top of /etc\n", RUN_ETC_DIR);
if (mount(RUN_ETC_DIR, "/etc", NULL, MS_BIND|MS_REC, NULL) < 0)
errExit("mount bind");
fs_logger("mount /etc");
}
static int store_asoundrc(void) {
// put a copy of .Xauthority in XAUTHORITY_FILE
fs_build_mnt_dir();
char *src;
char *dest = RUN_ASOUNDRC_FILE;
if (asprintf(&src, "%s/.asoundrc", cfg.homedir) == -1)
errExit("asprintf");
struct stat s;
if (stat(src, &s) == 0) {
if (is_link(src)) {
// make sure the real path of the file is inside the home directory
char* rp = realpath(src, NULL);
if (!rp) {
fprintf(stderr, "Error: Cannot access %s\n", src);
exit(1);
}
if (strncmp(rp, cfg.homedir, strlen(cfg.homedir)) != 0) {
fprintf(stderr, "Error: .asoundrc is a symbolic link pointing to a file outside home directory\n");
exit(1);
}
free(rp);
}
int rv = copy_file(src, dest);
if (rv) {
fprintf(stderr, "Warning: cannot transfer .asoundrc in private home directory\n");
return 0;
}
return 1; // file copied
}
return 0;
}
// grab a copy of cp command
void fs_build_cp_command(void) {
struct stat s;
fs_build_mnt_dir();
if (stat(RUN_CP_COMMAND, &s)) {
char* fname = realpath("/bin/cp", NULL);
if (fname == NULL) {
fprintf(stderr, "Error: /bin/cp not found\n");
exit(1);
}
if (stat(fname, &s)) {
fprintf(stderr, "Error: /bin/cp not found\n");
exit(1);
}
if (is_link(fname)) {
fprintf(stderr, "Error: invalid /bin/cp file\n");
exit(1);
}
int rv = copy_file(fname, RUN_CP_COMMAND);
if (rv) {
fprintf(stderr, "Error: cannot access /bin/cp\n");
exit(1);
}
/* coverity[toctou] */
if (chown(RUN_CP_COMMAND, 0, 0))
errExit("chown");
if (chmod(RUN_CP_COMMAND, 0755))
errExit("chmod");
free(fname);
}
}
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");
}
static void sanitize_home(void) {
assert(getuid() != 0); // this code works only for regular users
if (arg_debug)
printf("Cleaning /home directory\n");
struct stat s;
if (stat(cfg.homedir, &s) == -1) {
// cannot find home directory, just return
fprintf(stderr, "Warning: cannot find home directory\n");
return;
}
fs_build_mnt_dir();
if (mkdir(RUN_WHITELIST_HOME_DIR, 0755) == -1)
errExit("mkdir");
// keep a copy of the user home directory
if (mount(cfg.homedir, RUN_WHITELIST_HOME_DIR, NULL, MS_BIND|MS_REC, NULL) < 0)
errExit("mount bind");
// mount tmpfs in the new home
if (mount("tmpfs", "/home", "tmpfs", MS_NOSUID | MS_NODEV | MS_STRICTATIME | MS_REC, "mode=755,gid=0") < 0)
errExit("mount tmpfs");
fs_logger("tmpfs /home");
// create user home directory
if (mkdir(cfg.homedir, 0755) == -1) {
if (mkpath_as_root(cfg.homedir))
errExit("mkpath");
if (mkdir(cfg.homedir, 0755) == -1)
errExit("mkdir");
}
fs_logger2("mkdir", cfg.homedir);
// set mode and ownership
if (chown(cfg.homedir, s.st_uid, s.st_gid) == -1)
errExit("chown");
if (chmod(cfg.homedir, s.st_mode) == -1)
errExit("chmod");
// mount user home directory
if (mount(RUN_WHITELIST_HOME_DIR, cfg.homedir, NULL, MS_BIND|MS_REC, NULL) < 0)
errExit("mount bind");
// mask home dir under /run
if (mount("tmpfs", RUN_WHITELIST_HOME_DIR, "tmpfs", MS_NOSUID | MS_NODEV | MS_STRICTATIME | MS_REC, "mode=755,gid=0") < 0)
errExit("mount tmpfs");
fs_logger2("tmpfs", RUN_WHITELIST_HOME_DIR);
if (!arg_private)
fs_logger2("whitelist", cfg.homedir);
}
void fs_var_utmp(void) {
struct stat s;
// extract utmp group id
gid_t utmp_group = 0;
if (stat("/var/run/utmp", &s) == 0)
utmp_group = s.st_gid;
else {
fprintf(stderr, "Warning: cannot find /var/run/utmp\n");
return;
}
// create /tmp/firejail/mnt directory
fs_build_mnt_dir();
// create a new utmp file
if (arg_debug)
printf("Create the new utmp file\n");
char *utmp;
if (asprintf(&utmp, "%s/utmp", MNT_DIR) == -1)
errExit("asprintf");
FILE *fp = fopen(utmp, "w");
if (!fp)
errExit("fopen");
// read current utmp
struct utmp *u;
struct utmp u_boot;
setutent();
while ((u = getutent()) != NULL) {
if (u->ut_type == BOOT_TIME) {
memcpy(&u_boot, u, sizeof(u_boot));
u_boot.ut_tv.tv_sec = (unsigned) time(NULL);
}
}
endutent();
// save new utmp file
fwrite(&u_boot, sizeof(u_boot), 1, fp);
fclose(fp);
if (chown(utmp, 0, utmp_group) < 0)
errExit("chown");
if (chmod(utmp, S_IRUSR | S_IWRITE | S_IRGRP | S_IWGRP | S_IROTH ) < 0)
errExit("chmod");
// mount the new utmp file
if (arg_debug)
printf("Mount the new utmp file\n");
if (mount(utmp, "/var/run/utmp", NULL, MS_BIND|MS_REC, NULL) < 0)
errExit("mount bind utmp");
}
void fs_mount_xauthority(void) {
// put a copy of .Xauthority in MNT_DIR
fs_build_mnt_dir();
char *src;
char *dest;
if (asprintf(&dest, "%s/.Xauthority", cfg.homedir) == -1)
errExit("asprintf");
if (asprintf(&src, "%s/.Xauthority", MNT_DIR) == -1)
errExit("asprintf");
// bind-mount the file on top of /etc/hostname
if (mount(src, "dest", NULL, MS_BIND|MS_REC, NULL) < 0)
errExit("mount bind ~/.Xauthority");
}
// disable shm in pulseaudio
void pulseaudio_init(void) {
struct stat s;
// do we have pulseaudio in the system?
if (stat("/etc/pulse/client.conf", &s) == -1)
return;
// create the new user pulseaudio directory
fs_build_mnt_dir();
char *pulsedir;
if (asprintf(&pulsedir, "%s/pulse", MNT_DIR) == -1)
errExit("asprintf");
int rv = mkdir(pulsedir, S_IRWXU | S_IRWXG | S_IRWXO);
if (rv == -1)
errExit("mkdir");
if (chown(pulsedir, getuid(), getgid()) < 0)
errExit("chown");
if (chmod(pulsedir, 0700) < 0)
errExit("chmod");
// create the new client.conf file
char *pulsecfg = NULL;
if (asprintf(&pulsecfg, "%s/client.conf", pulsedir) == -1)
errExit("asprintf");
if (copy_file("/etc/pulse/client.conf", pulsecfg))
errExit("copy_file");
FILE *fp = fopen(pulsecfg, "a+");
if (!fp)
errExit("fopen");
fprintf(fp, "%s", "\nenable-shm = no\n");
fclose(fp);
if (chmod(pulsecfg, 0644) == -1)
errExit("chmod");
if (chown(pulsecfg, getuid(), getgid()) == -1)
errExit("chown");
// set environment
if (setenv("PULSE_CLIENTCONFIG", pulsecfg, 1) < 0)
errExit("setenv");
free(pulsecfg);
free(pulsedir);
}
void protocol_filter_save(void) {
// save protocol filter configuration in PROTOCOL_CFG
fs_build_mnt_dir();
FILE *fp = fopen(RUN_PROTOCOL_CFG, "w");
if (!fp)
errExit("fopen");
fprintf(fp, "%s\n", cfg.protocol);
fclose(fp);
if (chmod(RUN_PROTOCOL_CFG, 0600) < 0)
errExit("chmod");
if (chown(RUN_PROTOCOL_CFG, 0, 0) < 0)
errExit("chown");
}
// save seccomp filter in /tmp/firejail/mnt/seccomp
static void write_seccomp_file(void) {
fs_build_mnt_dir();
assert(sfilter);
int fd = open(RUN_SECCOMP_CFG, O_CREAT | O_WRONLY, S_IRUSR | S_IWUSR);
if (fd == -1)
errExit("open");
if (arg_debug)
printf("Save seccomp filter, size %u bytes\n", (unsigned) (sfilter_index * sizeof(struct sock_filter)));
errno = 0;
ssize_t sz = write(fd, sfilter, sfilter_index * sizeof(struct sock_filter));
if (sz != (ssize_t)(sfilter_index * sizeof(struct sock_filter))) {
fprintf(stderr, "Error: cannot save seccomp filter\n");
exit(1);
}
close(fd);
if (chown(RUN_SECCOMP_CFG, 0, 0) < 0)
errExit("chown");
}
static int store_xauthority(void) {
// put a copy of .Xauthority in MNT_DIR
fs_build_mnt_dir();
char *src;
char *dest;
if (asprintf(&src, "%s/.Xauthority", cfg.homedir) == -1)
errExit("asprintf");
if (asprintf(&dest, "%s/.Xauthority", MNT_DIR) == -1)
errExit("asprintf");
struct stat s;
if (stat(src, &s) == 0) {
int rv = copy_file(src, dest);
if (rv) {
exechelp_logerrv("firejail", FIREJAIL_WARNING, "Error: cannot transfer .Xauthority in private home directory\n");
return 0;
}
return 1; // file copied
}
return 0;
}
static int store_xauthority(void) {
// put a copy of .Xauthority in MNT_DIR
fs_build_mnt_dir();
char *src;
char *dest;
if (asprintf(&src, "%s/.Xauthority", cfg.homedir) == -1)
errExit("asprintf");
if (asprintf(&dest, "%s/.Xauthority", MNT_DIR) == -1)
errExit("asprintf");
struct stat s;
if (stat(src, &s) == 0) {
int rv = copy_file(src, dest);
if (rv) {
fprintf(stderr, "Warning: cannot transfer .Xauthority in private home directory\n");
return 0;
}
return 1; // file copied
}
return 0;
}
static void copy_xauthority(void) {
// put a copy of .Xauthority in MNT_DIR
fs_build_mnt_dir();
char *src;
char *dest;
if (asprintf(&dest, "%s/.Xauthority", cfg.homedir) == -1)
errExit("asprintf");
if (asprintf(&src, "%s/.Xauthority", MNT_DIR) == -1)
errExit("asprintf");
int rv = copy_file(src, dest);
if (rv)
exechelp_logerrv("firejail", FIREJAIL_WARNING, "Error: cannot transfer .Xauthority in private home directory\n");
// set permissions and ownership
if (chown(dest, getuid(), getgid()) < 0)
errExit("chown");
if (chmod(dest, S_IRUSR | S_IWUSR) < 0)
errExit("chmod");
// delete the temporary file
unlink(src);
}
void fs_copy_xauthority(void) {
// put a copy of .Xauthority in MNT_DIR
fs_build_mnt_dir();
char *src;
char *dest;
if (asprintf(&dest, "%s/.Xauthority", cfg.homedir) == -1)
errExit("asprintf");
if (asprintf(&src, "%s/.Xauthority", MNT_DIR) == -1)
errExit("asprintf");
int rv = copy_file(src, dest);
if (rv)
fprintf(stderr, "Warning: cannot transfer .Xauthority in private home directory\n");
// set permissions and ownership
if (chown(dest, getuid(), getgid()) < 0)
errExit("chown");
if (chmod(dest, S_IRUSR | S_IWUSR) < 0)
errExit("chmod");
// delete the temporary file
unlink(src);
}
// save seccomp filter in /tmp/firejail/mnt/seccomp
static void write_seccomp_file(void) {
fs_build_mnt_dir();
assert(sfilter);
char *fname;
if (asprintf(&fname, "%s/seccomp", MNT_DIR) == -1)
errExit("asprintf");
int fd = open(fname, O_CREAT | O_WRONLY, S_IRUSR | S_IWUSR);
if (fd == -1)
errExit("open");
if (arg_debug)
printf("Save seccomp filter, size %lu bytes\n", sfilter_index * sizeof(struct sock_filter));
errno = 0;
ssize_t sz = write(fd, sfilter, sfilter_index * sizeof(struct sock_filter));
if (sz != (ssize_t)(sfilter_index * sizeof(struct sock_filter))) {
exechelp_logerrv("firejail", FIREJAIL_ERROR, "Error: cannot save seccomp filter\n");
exit(1);
}
close(fd);
if (chown(fname, 0, 0) < 0)
errExit("chown");
free(fname);
}
// grab a copy of cp command
void fs_build_cp_command(void) {
struct stat s;
fs_build_mnt_dir();
if (stat(CP_COMMAND, &s)) {
char* fname = realpath("/bin/cp", NULL);
if (fname == NULL) {
fprintf(stderr, "Error: /bin/cp not found\n");
exit(1);
}
if (stat(fname, &s)) {
fprintf(stderr, "Error: /bin/cp not found\n");
exit(1);
}
int rv = copy_file(fname, CP_COMMAND);
if (rv) {
fprintf(stderr, "Error: cannot access /bin/cp\n");
exit(1);
}
if (chmod(CP_COMMAND, 0755))
errExit("chmod");
free(fname);
}
}
void fs_overlayfs(void) {
// check kernel version
struct utsname u;
int rv = uname(&u);
if (rv != 0)
errExit("uname");
int major;
int minor;
if (2 != sscanf(u.release, "%d.%d", &major, &minor)) {
fprintf(stderr, "Error: cannot extract Linux kernel version: %s\n", u.version);
exit(1);
}
if (arg_debug)
printf("Linux kernel version %d.%d\n", major, minor);
int oldkernel = 0;
if (major < 3) {
fprintf(stderr, "Error: minimum kernel version required 3.x\n");
exit(1);
}
if (major == 3 && minor < 18)
oldkernel = 1;
// build overlay directories
fs_build_mnt_dir();
char *oroot;
if(asprintf(&oroot, "%s/oroot", RUN_MNT_DIR) == -1)
errExit("asprintf");
if (mkdir(oroot, 0755))
errExit("mkdir");
if (chown(oroot, 0, 0) < 0)
errExit("chown");
if (chmod(oroot, 0755) < 0)
errExit("chmod");
char *basedir = RUN_MNT_DIR;
if (arg_overlay_keep) {
// set base for working and diff directories
basedir = cfg.overlay_dir;
if (mkdir(basedir, 0755) != 0) {
fprintf(stderr, "Error: cannot create overlay directory\n");
exit(1);
}
}
char *odiff;
if(asprintf(&odiff, "%s/odiff", basedir) == -1)
errExit("asprintf");
if (mkdir(odiff, 0755))
errExit("mkdir");
if (chown(odiff, 0, 0) < 0)
errExit("chown");
if (chmod(odiff, 0755) < 0)
errExit("chmod");
char *owork;
if(asprintf(&owork, "%s/owork", basedir) == -1)
errExit("asprintf");
if (mkdir(owork, 0755))
errExit("mkdir");
if (chown(owork, 0, 0) < 0)
errExit("chown");
if (chmod(owork, 0755) < 0)
errExit("chmod");
// mount overlayfs
if (arg_debug)
printf("Mounting OverlayFS\n");
char *option;
if (oldkernel) { // old Ubuntu/OpenSUSE kernels
if (arg_overlay_keep) {
fprintf(stderr, "Error: option --overlay= not available for kernels older than 3.18\n");
exit(1);
}
if (asprintf(&option, "lowerdir=/,upperdir=%s", odiff) == -1)
errExit("asprintf");
if (mount("overlayfs", oroot, "overlayfs", MS_MGC_VAL, option) < 0)
errExit("mounting overlayfs");
}
else { // kernel 3.18 or newer
if (asprintf(&option, "lowerdir=/,upperdir=%s,workdir=%s", odiff, owork) == -1)
errExit("asprintf");
//printf("option #%s#\n", option);
if (mount("overlay", oroot, "overlay", MS_MGC_VAL, option) < 0)
errExit("mounting overlayfs");
}
printf("OverlayFS configured in %s directory\n", basedir);
// mount-bind dev directory
if (arg_debug)
printf("Mounting /dev\n");
char *dev;
if (asprintf(&dev, "%s/dev", oroot) == -1)
errExit("asprintf");
if (mount("/dev", dev, NULL, MS_BIND|MS_REC, NULL) < 0)
errExit("mounting /dev");
// chroot in the new filesystem
if (chroot(oroot) == -1)
errExit("chroot");
// update /var directory in order to support multiple sandboxes running on the same root directory
if (!arg_private_dev)
fs_dev_shm();
fs_var_lock();
fs_var_tmp();
fs_var_log();
fs_var_lib();
fs_var_cache();
fs_var_utmp();
// don't leak user information
restrict_users();
disable_firejail_config();
// cleanup and exit
free(option);
free(oroot);
free(odiff);
}
void fs_overlayfs(void) {
// check kernel version
struct utsname u;
int rv = uname(&u);
if (rv != 0)
errExit("uname");
int major;
int minor;
if (2 != sscanf(u.release, "%d.%d", &major, &minor)) {
fprintf(stderr, "Error: cannot extract Linux kernel version: %s\n", u.version);
exit(1);
}
if (arg_debug)
printf("Linux kernel version %d.%d\n", major, minor);
int oldkernel = 0;
if (major < 3) {
fprintf(stderr, "Error: minimum kernel version required 3.x\n");
exit(1);
}
if (major == 3 && minor < 18)
oldkernel = 1;
// build overlay directories
fs_build_mnt_dir();
char *oroot;
if(asprintf(&oroot, "%s/oroot", RUN_MNT_DIR) == -1)
errExit("asprintf");
if (mkdir(oroot, 0755))
errExit("mkdir");
if (chown(oroot, 0, 0) < 0)
errExit("chown");
if (chmod(oroot, 0755) < 0)
errExit("chmod");
char *basedir = RUN_MNT_DIR;
if (arg_overlay_keep) {
// set base for working and diff directories
basedir = cfg.overlay_dir;
if (mkdir(basedir, 0755) != 0) {
fprintf(stderr, "Error: cannot create overlay directory\n");
exit(1);
}
}
char *odiff;
if(asprintf(&odiff, "%s/odiff", basedir) == -1)
errExit("asprintf");
if (mkdir(odiff, 0755))
errExit("mkdir");
if (chown(odiff, 0, 0) < 0)
errExit("chown");
if (chmod(odiff, 0755) < 0)
errExit("chmod");
char *owork;
if(asprintf(&owork, "%s/owork", basedir) == -1)
errExit("asprintf");
if (mkdir(owork, 0755))
errExit("mkdir");
if (chown(owork, 0, 0) < 0)
errExit("chown");
if (chmod(owork, 0755) < 0)
errExit("chmod");
// mount overlayfs
if (arg_debug)
printf("Mounting OverlayFS\n");
char *option;
if (oldkernel) { // old Ubuntu/OpenSUSE kernels
if (arg_overlay_keep) {
fprintf(stderr, "Error: option --overlay= not available for kernels older than 3.18\n");
exit(1);
}
if (asprintf(&option, "lowerdir=/,upperdir=%s", odiff) == -1)
errExit("asprintf");
if (mount("overlayfs", oroot, "overlayfs", MS_MGC_VAL, option) < 0)
errExit("mounting overlayfs");
}
else { // kernel 3.18 or newer
if (asprintf(&option, "lowerdir=/,upperdir=%s,workdir=%s", odiff, owork) == -1)
errExit("asprintf");
if (mount("overlay", oroot, "overlay", MS_MGC_VAL, option) < 0)
errExit("mounting overlayfs");
//***************************
// issue #263 start code
// My setup has a separate mount point for /home. When the overlay is mounted,
// the overlay does not contain the original /home contents.
// I added code to create a second overlay for /home if the overlay home dir is empty and this seems to work
// @dshmgh, Jan 2016
{
char *overlayhome;
struct stat s;
char *hroot;
char *hdiff;
char *hwork;
// dons add debug
if (arg_debug) printf ("DEBUG: chroot dirs are oroot %s odiff %s owork %s\n",oroot,odiff,owork);
// BEFORE NEXT, WE NEED TO TEST IF /home has any contents or do we need to mount it?
// must create var for oroot/cfg.homedir
if (asprintf(&overlayhome,"%s%s",oroot,cfg.homedir) == -1)
errExit("asprintf");
if (arg_debug) printf ("DEBUG: overlayhome var holds ##%s##\n",overlayhome);
// if no homedir in overlay -- create another overlay for /home
if (stat(overlayhome, &s) == -1) {
if(asprintf(&hroot, "%s/oroot/home", RUN_MNT_DIR) == -1)
errExit("asprintf");
if(asprintf(&hdiff, "%s/hdiff", basedir) == -1)
errExit("asprintf");
if (mkdir(hdiff, S_IRWXU | S_IRWXG | S_IRWXO))
errExit("mkdir");
if (chown(hdiff, 0, 0) < 0)
errExit("chown");
if (chmod(hdiff, S_IRWXU | S_IRGRP | S_IXGRP | S_IROTH | S_IXOTH) < 0)
errExit("chmod");
if(asprintf(&hwork, "%s/hwork", basedir) == -1)
errExit("asprintf");
if (mkdir(hwork, S_IRWXU | S_IRWXG | S_IRWXO))
errExit("mkdir");
if (chown(hwork, 0, 0) < 0)
errExit("chown");
if (chmod(hwork, S_IRWXU | S_IRGRP | S_IXGRP | S_IROTH | S_IXOTH) < 0)
errExit("chmod");
// no homedir in overlay so now mount another overlay for /home
if (asprintf(&option, "lowerdir=/home,upperdir=%s,workdir=%s", hdiff, hwork) == -1)
errExit("asprintf");
if (mount("overlay", hroot, "overlay", MS_MGC_VAL, option) < 0)
errExit("mounting overlayfs for mounted home directory");
printf("OverlayFS for /home configured in %s directory\n", basedir);
} // stat(overlayhome)
free(overlayhome);
}
// issue #263 end code
//***************************
}
printf("OverlayFS configured in %s directory\n", basedir);
// mount-bind dev directory
if (arg_debug)
printf("Mounting /dev\n");
char *dev;
if (asprintf(&dev, "%s/dev", oroot) == -1)
errExit("asprintf");
if (mount("/dev", dev, NULL, MS_BIND|MS_REC, NULL) < 0)
errExit("mounting /dev");
fs_logger("whitelist /dev");
// mount-bind run directory
if (arg_debug)
printf("Mounting /run\n");
char *run;
if (asprintf(&run, "%s/run", oroot) == -1)
errExit("asprintf");
if (mount("/run", run, NULL, MS_BIND|MS_REC, NULL) < 0)
errExit("mounting /run");
fs_logger("whitelist /run");
// chroot in the new filesystem
if (chroot(oroot) == -1)
errExit("chroot");
// update /var directory in order to support multiple sandboxes running on the same root directory
if (!arg_private_dev)
fs_dev_shm();
fs_var_lock();
fs_var_tmp();
fs_var_log();
fs_var_lib();
fs_var_cache();
fs_var_utmp();
// don't leak user information
restrict_users();
// when starting as root, firejail config is not disabled;
// this mode could be used to install and test new software by chaining
// firejail sandboxes (firejail --force)
if (getuid() != 0)
disable_firejail_config();
else
fprintf(stderr, "Warning: masking /etc/firejail disabled when starting the sandbox as root\n");
// cleanup and exit
free(option);
free(oroot);
free(odiff);
}
// whitelist for /home/user directory
void fs_whitelist(void) {
char *homedir = cfg.homedir;
assert(homedir);
ProfileEntry *entry = cfg.profile;
if (!entry)
return;
char *new_name = NULL;
int home_dir = 0; // /home/user directory flag
int tmp_dir = 0; // /tmp directory flag
int media_dir = 0; // /media directory flag
int var_dir = 0; // /var directory flag
int dev_dir = 0; // /dev directory flag
int opt_dir = 0; // /opt directory flag
// verify whitelist files, extract symbolic links, etc.
while (entry) {
// handle only whitelist commands
if (strncmp(entry->data, "whitelist ", 10)) {
entry = entry->next;
continue;
}
// resolve ${DOWNLOADS}
if (strcmp(entry->data + 10, "${DOWNLOADS}") == 0) {
char *tmp = resolve_downloads();
if (tmp)
entry->data = tmp;
else {
*entry->data = '\0';
fprintf(stderr, "***\n");
fprintf(stderr, "*** Warning: cannot whitelist Downloads directory\n");
fprintf(stderr, "*** \tAny file saved will be lost when the sandbox is closed.\n");
fprintf(stderr, "*** \tPlease create a proper Downloads directory for your application.\n");
fprintf(stderr, "***\n");
continue;
}
}
// replace ~/ or ${HOME} into /home/username
new_name = expand_home(entry->data + 10, cfg.homedir);
assert(new_name);
if (arg_debug)
fprintf(stderr, "Debug %d: new_name #%s#\n", __LINE__, new_name);
// extract the absolute path of the file
// realpath function will fail with ENOENT if the file is not found
char *fname = realpath(new_name, NULL);
if (!fname) {
// file not found, blank the entry in the list and continue
if (arg_debug || arg_debug_whitelists) {
printf("Removed whitelist path: %s\n", entry->data);
printf("\texpanded: %s\n", new_name);
printf("\treal path: (null)\n");
printf("\t");fflush(0);
perror("realpath");
}
*entry->data = '\0';
continue;
}
// valid path referenced to filesystem root
if (*new_name != '/') {
if (arg_debug)
fprintf(stderr, "Debug %d: \n", __LINE__);
goto errexit;
}
// check for supported directories
if (strncmp(new_name, cfg.homedir, strlen(cfg.homedir)) == 0) {
// whitelisting home directory is disabled if --private or --private-home option is present
if (arg_private) {
if (arg_debug || arg_debug_whitelists)
printf("Removed whitelist path %s, --private option is present\n", entry->data);
*entry->data = '\0';
continue;
}
entry->home_dir = 1;
home_dir = 1;
// both path and absolute path are under /home
if (strncmp(fname, cfg.homedir, strlen(cfg.homedir)) != 0) {
if (arg_debug)
fprintf(stderr, "Debug %d: fname #%s#, cfg.homedir #%s#\n",
__LINE__, fname, cfg.homedir);
goto errexit;
}
}
else if (strncmp(new_name, "/tmp/", 5) == 0) {
entry->tmp_dir = 1;
tmp_dir = 1;
// both path and absolute path are under /tmp
if (strncmp(fname, "/tmp/", 5) != 0) {
if (arg_debug)
fprintf(stderr, "Debug %d: fname #%s#\n", __LINE__, fname);
goto errexit;
}
}
else if (strncmp(new_name, "/media/", 7) == 0) {
entry->media_dir = 1;
media_dir = 1;
// both path and absolute path are under /media
if (strncmp(fname, "/media/", 7) != 0) {
if (arg_debug)
fprintf(stderr, "Debug %d: fname #%s#\n", __LINE__, fname);
goto errexit;
}
}
else if (strncmp(new_name, "/var/", 5) == 0) {
entry->var_dir = 1;
var_dir = 1;
// both path and absolute path are under /var
if (strncmp(fname, "/var/", 5) != 0) {
if (arg_debug)
fprintf(stderr, "Debug %d: fname #%s#\n", __LINE__, fname);
goto errexit;
}
}
else if (strncmp(new_name, "/dev/", 5) == 0) {
entry->dev_dir = 1;
dev_dir = 1;
// both path and absolute path are under /dev
if (strncmp(fname, "/dev/", 5) != 0) {
if (arg_debug)
fprintf(stderr, "Debug %d: fname #%s#\n", __LINE__, fname);
goto errexit;
}
}
else if (strncmp(new_name, "/opt/", 5) == 0) {
entry->opt_dir = 1;
opt_dir = 1;
// both path and absolute path are under /dev
if (strncmp(fname, "/opt/", 5) != 0) {
if (arg_debug)
fprintf(stderr, "Debug %d: fname #%s#\n", __LINE__, fname);
goto errexit;
}
}
else {
if (arg_debug)
fprintf(stderr, "Debug %d: \n", __LINE__);
goto errexit;
}
// mark symbolic links
if (is_link(new_name))
entry->link = new_name;
else {
free(new_name);
new_name = NULL;
}
// change file name in entry->data
if (strcmp(fname, entry->data + 10) != 0) {
char *newdata;
if (asprintf(&newdata, "whitelist %s", fname) == -1)
errExit("asprintf");
entry->data = newdata;
if (arg_debug || arg_debug_whitelists)
printf("Replaced whitelist path: %s\n", entry->data);
}
free(fname);
entry = entry->next;
}
// create mount points
fs_build_mnt_dir();
// /home/user
if (home_dir) {
// keep a copy of real home dir in RUN_WHITELIST_HOME_USER_DIR
int rv = mkdir(RUN_WHITELIST_HOME_USER_DIR, S_IRWXU | S_IRWXG | S_IRWXO);
if (rv == -1)
errExit("mkdir");
if (chown(RUN_WHITELIST_HOME_USER_DIR, getuid(), getgid()) < 0)
errExit("chown");
if (chmod(RUN_WHITELIST_HOME_USER_DIR, 0755) < 0)
errExit("chmod");
if (mount(cfg.homedir, RUN_WHITELIST_HOME_USER_DIR, NULL, MS_BIND|MS_REC, NULL) < 0)
errExit("mount bind");
// mount a tmpfs and initialize /home/user
fs_private();
}
// /tmp mountpoint
if (tmp_dir) {
// keep a copy of real /tmp directory in WHITELIST_TMP_DIR
int rv = mkdir(RUN_WHITELIST_TMP_DIR, S_IRWXU | S_IRWXG | S_IRWXO);
if (rv == -1)
errExit("mkdir");
if (chown(RUN_WHITELIST_TMP_DIR, 0, 0) < 0)
errExit("chown");
if (chmod(RUN_WHITELIST_TMP_DIR, 0777) < 0)
errExit("chmod");
if (mount("/tmp", RUN_WHITELIST_TMP_DIR, NULL, MS_BIND|MS_REC, NULL) < 0)
errExit("mount bind");
// mount tmpfs on /tmp
if (arg_debug || arg_debug_whitelists)
printf("Mounting tmpfs on /tmp directory\n");
if (mount("tmpfs", "/tmp", "tmpfs", MS_NOSUID | MS_STRICTATIME | MS_REC, "mode=777,gid=0") < 0)
errExit("mounting tmpfs on /tmp");
fs_logger("mount tmpfs on /tmp");
}
// /media mountpoint
if (media_dir) {
// keep a copy of real /media directory in RUN_WHITELIST_MEDIA_DIR
int rv = mkdir(RUN_WHITELIST_MEDIA_DIR, S_IRWXU | S_IRWXG | S_IRWXO);
if (rv == -1)
errExit("mkdir");
if (chown(RUN_WHITELIST_MEDIA_DIR, 0, 0) < 0)
errExit("chown");
if (chmod(RUN_WHITELIST_MEDIA_DIR, 0755) < 0)
errExit("chmod");
if (mount("/media", RUN_WHITELIST_MEDIA_DIR, NULL, MS_BIND|MS_REC, NULL) < 0)
errExit("mount bind");
// mount tmpfs on /media
if (arg_debug || arg_debug_whitelists)
printf("Mounting tmpfs on /media directory\n");
if (mount("tmpfs", "/media", "tmpfs", MS_NOSUID | MS_STRICTATIME | MS_REC, "mode=755,gid=0") < 0)
errExit("mounting tmpfs on /media");
fs_logger("mount tmpfs on /media");
}
// /var mountpoint
if (var_dir) {
// keep a copy of real /var directory in RUN_WHITELIST_VAR_DIR
int rv = mkdir(RUN_WHITELIST_VAR_DIR, S_IRWXU | S_IRWXG | S_IRWXO);
if (rv == -1)
errExit("mkdir");
if (chown(RUN_WHITELIST_VAR_DIR, 0, 0) < 0)
errExit("chown");
if (chmod(RUN_WHITELIST_VAR_DIR, 0755) < 0)
errExit("chmod");
if (mount("/var", RUN_WHITELIST_VAR_DIR, NULL, MS_BIND|MS_REC, NULL) < 0)
errExit("mount bind");
// mount tmpfs on /var
if (arg_debug || arg_debug_whitelists)
printf("Mounting tmpfs on /var directory\n");
if (mount("tmpfs", "/var", "tmpfs", MS_NOSUID | MS_STRICTATIME | MS_REC, "mode=755,gid=0") < 0)
errExit("mounting tmpfs on /var");
fs_logger("mount tmpfs on /var");
}
// /dev mountpoint
if (dev_dir) {
// keep a copy of real /dev directory in RUN_WHITELIST_DEV_DIR
int rv = mkdir(RUN_WHITELIST_DEV_DIR, S_IRWXU | S_IRWXG | S_IRWXO);
if (rv == -1)
errExit("mkdir");
if (chown(RUN_WHITELIST_DEV_DIR, 0, 0) < 0)
errExit("chown");
if (chmod(RUN_WHITELIST_DEV_DIR, 0755) < 0)
errExit("chmod");
if (mount("/dev", RUN_WHITELIST_DEV_DIR, NULL, MS_BIND|MS_REC, NULL) < 0)
errExit("mount bind");
// mount tmpfs on /dev
if (arg_debug || arg_debug_whitelists)
printf("Mounting tmpfs on /dev directory\n");
if (mount("tmpfs", "/dev", "tmpfs", MS_NOSUID | MS_STRICTATIME | MS_REC, "mode=755,gid=0") < 0)
errExit("mounting tmpfs on /dev");
fs_logger("mount tmpfs on /dev");
}
// /opt mountpoint
if (opt_dir) {
// keep a copy of real /opt directory in RUN_WHITELIST_DEV_DIR
int rv = mkdir(RUN_WHITELIST_OPT_DIR, S_IRWXU | S_IRWXG | S_IRWXO);
if (rv == -1)
errExit("mkdir");
if (chown(RUN_WHITELIST_OPT_DIR, 0, 0) < 0)
errExit("chown");
if (chmod(RUN_WHITELIST_OPT_DIR, 0755) < 0)
errExit("chmod");
if (mount("/opt", RUN_WHITELIST_OPT_DIR, NULL, MS_BIND|MS_REC, NULL) < 0)
errExit("mount bind");
// mount tmpfs on /opt
if (arg_debug || arg_debug_whitelists)
printf("Mounting tmpfs on /opt directory\n");
if (mount("tmpfs", "/opt", "tmpfs", MS_NOSUID | MS_STRICTATIME | MS_REC, "mode=755,gid=0") < 0)
errExit("mounting tmpfs on /opt");
fs_logger("mount tmpfs on /opt");
}
// go through profile rules again, and interpret whitelist commands
entry = cfg.profile;
while (entry) {
// handle only whitelist commands
if (strncmp(entry->data, "whitelist ", 10)) {
entry = entry->next;
continue;
}
//printf("here %d#%s#\n", __LINE__, entry->data);
// whitelist the real file
whitelist_path(entry);
// create the link if any
if (entry->link) {
// if the link is already there, do not bother
struct stat s;
if (stat(entry->link, &s) != 0) {
// create the path if necessary
mkpath(entry->link, s.st_mode);
int rv = symlink(entry->data + 10, entry->link);
if (rv)
fprintf(stderr, "Warning cannot create symbolic link %s\n", entry->link);
else if (arg_debug || arg_debug_whitelists)
printf("Created symbolic link %s -> %s\n", entry->link, entry->data + 10);
}
}
entry = entry->next;
}
// mask the real home directory, currently mounted on RUN_WHITELIST_HOME_DIR
if (home_dir) {
if (mount("tmpfs", RUN_WHITELIST_HOME_USER_DIR, "tmpfs", MS_NOSUID | MS_STRICTATIME | MS_REC, "mode=755,gid=0") < 0)
errExit("mount tmpfs");
}
// mask the real /tmp directory, currently mounted on RUN_WHITELIST_TMP_DIR
if (tmp_dir) {
if (mount("tmpfs", RUN_WHITELIST_TMP_DIR, "tmpfs", MS_NOSUID | MS_STRICTATIME | MS_REC, "mode=755,gid=0") < 0)
errExit("mount tmpfs");
}
if (new_name)
free(new_name);
return;
errexit:
fprintf(stderr, "Error: invalid whitelist path %s\n", new_name);
exit(1);
}
void fs_private_dev(void){
// install a new /dev directory
if (arg_debug)
printf("Mounting tmpfs on /dev\n");
// create DRI_DIR
fs_build_mnt_dir();
// keep a copy of dev directory
if (mkdir(RUN_DEV_DIR, 0755) == -1)
errExit("mkdir");
if (chmod(RUN_DEV_DIR, 0755) == -1)
errExit("chmod");
ASSERT_PERMS(RUN_DEV_DIR, 0, 0, 0755);
if (mount("/dev", RUN_DEV_DIR, NULL, MS_BIND|MS_REC, NULL) < 0)
errExit("mounting /dev/dri");
// create DEVLOG_FILE
int have_devlog = 0;
struct stat s;
if (stat("/dev/log", &s) == 0) {
have_devlog = 1;
FILE *fp = fopen(RUN_DEVLOG_FILE, "w");
if (!fp)
have_devlog = 0;
else {
fprintf(fp, "\n");
fclose(fp);
if (mount("/dev/log", RUN_DEVLOG_FILE, NULL, MS_BIND|MS_REC, NULL) < 0)
errExit("mounting /dev/log");
}
}
// mount tmpfs on top of /dev
if (mount("tmpfs", "/dev", "tmpfs", MS_NOSUID | MS_STRICTATIME | MS_REC, "mode=755,gid=0") < 0)
errExit("mounting /dev");
fs_logger("tmpfs /dev");
deventry_mount();
// bring back /dev/log
if (have_devlog) {
FILE *fp = fopen("/dev/log", "w");
if (fp) {
fprintf(fp, "\n");
fclose(fp);
if (mount(RUN_DEVLOG_FILE, "/dev/log", NULL, MS_BIND|MS_REC, NULL) < 0)
errExit("mounting /dev/log");
fs_logger("clone /dev/log");
}
}
if (mount(RUN_RO_DIR, RUN_DEV_DIR, "none", MS_BIND, "mode=400,gid=0") < 0)
errExit("disable /dev/snd");
// create /dev/shm
if (arg_debug)
printf("Create /dev/shm directory\n");
if (mkdir("/dev/shm", 01777) == -1)
errExit("mkdir");
// mkdir sets only the file permission bits
if (chmod("/dev/shm", 01777) < 0)
errExit("chmod");
ASSERT_PERMS("/dev/shm", 0, 0, 01777);
fs_logger("mkdir /dev/shm");
// create devices
create_char_dev("/dev/zero", 0666, 1, 5); // mknod -m 666 /dev/zero c 1 5
fs_logger("mknod /dev/zero");
create_char_dev("/dev/null", 0666, 1, 3); // mknod -m 666 /dev/null c 1 3
fs_logger("mknod /dev/null");
create_char_dev("/dev/full", 0666, 1, 7); // mknod -m 666 /dev/full c 1 7
fs_logger("mknod /dev/full");
create_char_dev("/dev/random", 0666, 1, 8); // Mknod -m 666 /dev/random c 1 8
fs_logger("mknod /dev/random");
create_char_dev("/dev/urandom", 0666, 1, 9); // mknod -m 666 /dev/urandom c 1 9
fs_logger("mknod /dev/urandom");
create_char_dev("/dev/tty", 0666, 5, 0); // mknod -m 666 /dev/tty c 5 0
fs_logger("mknod /dev/tty");
#if 0
create_dev("/dev/tty0", "mknod -m 666 /dev/tty0 c 4 0");
create_dev("/dev/console", "mknod -m 622 /dev/console c 5 1");
#endif
// pseudo-terminal
if (mkdir("/dev/pts", 0755) == -1)
errExit("mkdir");
if (chmod("/dev/pts", 0755) == -1)
errExit("chmod");
ASSERT_PERMS("/dev/pts", 0, 0, 0755);
fs_logger("mkdir /dev/pts");
create_char_dev("/dev/pts/ptmx", 0666, 5, 2); //"mknod -m 666 /dev/pts/ptmx c 5 2");
fs_logger("mknod /dev/pts/ptmx");
create_link("/dev/pts/ptmx", "/dev/ptmx");
// code before github issue #351
// mount -vt devpts -o newinstance -o ptmxmode=0666 devpts //dev/pts
// if (mount("devpts", "/dev/pts", "devpts", MS_MGC_VAL, "newinstance,ptmxmode=0666") < 0)
// errExit("mounting /dev/pts");
// mount /dev/pts
gid_t ttygid = get_tty_gid();
char *data;
if (asprintf(&data, "newinstance,gid=%d,mode=620,ptmxmode=0666", (int) ttygid) == -1)
errExit("asprintf");
if (mount("devpts", "/dev/pts", "devpts", MS_MGC_VAL, data) < 0)
errExit("mounting /dev/pts");
free(data);
fs_logger("clone /dev/pts");
#if 0
// stdin, stdout, stderr
create_link("/proc/self/fd", "/dev/fd");
create_link("/proc/self/fd/0", "/dev/stdin");
create_link("/proc/self/fd/1", "/dev/stdout");
create_link("/proc/self/fd/2", "/dev/stderr");
#endif
}
void fs_private_bin_list(void) {
char *private_list = cfg.bin_private_keep;
assert(private_list);
// create /tmp/firejail/mnt/bin directory
fs_build_mnt_dir();
int rv = mkdir(RUN_BIN_DIR, 0755);
if (rv == -1)
errExit("mkdir");
if (chown(RUN_BIN_DIR, 0, 0) < 0)
errExit("chown");
if (chmod(RUN_BIN_DIR, 0755) < 0)
errExit("chmod");
// copy the list of files in the new etc directory
// using a new child process without root privileges
fs_logger_print(); // save the current log
pid_t child = fork();
if (child < 0)
errExit("fork");
if (child == 0) {
if (arg_debug)
printf("Copying files in the new home:\n");
// elevate privileges - files in the new /bin directory belong to root
if (setreuid(0, 0) < 0)
errExit("setreuid");
if (setregid(0, 0) < 0)
errExit("setregid");
// copy the list of files in the new home directory
char *dlist = strdup(private_list);
if (!dlist)
errExit("strdup");
char *ptr = strtok(dlist, ",");
duplicate(ptr);
while ((ptr = strtok(NULL, ",")) != NULL)
duplicate(ptr);
free(dlist);
fs_logger_print();
exit(0);
}
// wait for the child to finish
waitpid(child, NULL, 0);
// mount-bind
int i = 0;
while (paths[i]) {
struct stat s;
if (stat(paths[i], &s) == 0) {
if (arg_debug)
printf("Mount-bind %s on top of %s\n", RUN_BIN_DIR, paths[i]);
if (mount(RUN_BIN_DIR, paths[i], NULL, MS_BIND|MS_REC, NULL) < 0)
errExit("mount bind");
fs_logger2("tmpfs", paths[i]);
fs_logger2("mount", paths[i]);
}
i++;
}
// log cloned files
char *dlist = strdup(private_list);
if (!dlist)
errExit("strdup");
char *ptr = strtok(dlist, ",");
while (ptr) {
i = 0;
while (paths[i]) {
struct stat s;
if (stat(paths[i], &s) == 0) {
char *fname;
if (asprintf(&fname, "%s/%s", paths[i], ptr) == -1)
errExit("asprintf");
fs_logger2("clone", fname);
free(fname);
}
i++;
}
ptr = strtok(NULL, ",");
}
free(dlist);
}
// whitelist for /home/user directory
void fs_whitelist(void) {
char *homedir = cfg.homedir;
assert(homedir);
ProfileEntry *entry = cfg.profile;
if (!entry)
return;
char *new_name = NULL;
int home_dir = 0; // /home/user directory flag
int tmp_dir = 0; // /tmp directory flag
int media_dir = 0; // /media directory flag
int var_dir = 0; // /var directory flag
int dev_dir = 0; // /dev directory flag
// verify whitelist files, extract symbolic links, etc.
while (entry) {
// handle only whitelist commands
if (strncmp(entry->data, "whitelist ", 10)) {
entry = entry->next;
continue;
}
// replace ~/ or ${HOME} into /home/username
new_name = expand_home(entry->data + 10, cfg.homedir);
assert(new_name);
// extract the absolute path of the file
// realpath function will fail with ENOENT if the file is not found
char *fname = realpath(new_name, NULL);
if (!fname) {
// file not found, blank the entry in the list and continue
if (arg_debug)
printf("Removed whitelist path: %s\n", entry->data);
*entry->data = '\0';
continue;
}
// valid path referenced to filesystem root
if (*new_name != '/')
goto errexit;
// check for supported directories
if (strncmp(new_name, cfg.homedir, strlen(cfg.homedir)) == 0) {
entry->home_dir = 1;
home_dir = 1;
// both path and absolute path are under /home
if (strncmp(fname, cfg.homedir, strlen(cfg.homedir)) != 0)
goto errexit;
}
else if (strncmp(new_name, "/tmp/", 5) == 0) {
entry->tmp_dir = 1;
tmp_dir = 1;
// both path and absolute path are under /tmp
if (strncmp(fname, "/tmp/", 5) != 0)
goto errexit;
}
else if (strncmp(new_name, "/media/", 7) == 0) {
entry->media_dir = 1;
media_dir = 1;
// both path and absolute path are under /media
if (strncmp(fname, "/media/", 7) != 0)
goto errexit;
}
else if (strncmp(new_name, "/var/", 5) == 0) {
entry->var_dir = 1;
var_dir = 1;
// both path and absolute path are under /var
if (strncmp(fname, "/var/", 5) != 0)
goto errexit;
}
else if (strncmp(new_name, "/dev/", 5) == 0) {
entry->dev_dir = 1;
dev_dir = 1;
// both path and absolute path are under /dev
if (strncmp(fname, "/dev/", 5) != 0)
goto errexit;
}
else
goto errexit;
// mark symbolic links
if (is_link(new_name))
entry->link = new_name;
else
free(new_name);
// change file name in entry->data
if (strcmp(fname, entry->data + 10) != 0) {
char *newdata;
if (asprintf(&newdata, "whitelist %s", fname) == -1)
errExit("asprintf");
entry->data = newdata;
if (arg_debug)
printf("Replaced whitelist path: %s\n", entry->data);
}
free(fname);
entry = entry->next;
}
// create mount points
fs_build_mnt_dir();
// /home/user
if (home_dir) {
// keep a copy of real home dir in WHITELIST_HOME_DIR
int rv = mkdir(WHITELIST_HOME_DIR, S_IRWXU | S_IRWXG | S_IRWXO);
if (rv == -1)
errExit("mkdir");
if (chown(WHITELIST_HOME_DIR, getuid(), getgid()) < 0)
errExit("chown");
if (chmod(WHITELIST_HOME_DIR, 0755) < 0)
errExit("chmod");
if (mount(cfg.homedir, WHITELIST_HOME_DIR, NULL, MS_BIND|MS_REC, NULL) < 0)
errExit("mount bind");
// mount a tmpfs and initialize /home/user
fs_private();
}
// /tmp mountpoint
if (tmp_dir) {
// keep a copy of real /tmp directory in WHITELIST_TMP_DIR
int rv = mkdir(WHITELIST_TMP_DIR, S_IRWXU | S_IRWXG | S_IRWXO);
if (rv == -1)
errExit("mkdir");
if (chown(WHITELIST_TMP_DIR, 0, 0) < 0)
errExit("chown");
if (chmod(WHITELIST_TMP_DIR, 0777) < 0)
errExit("chmod");
if (mount("/tmp", WHITELIST_TMP_DIR, NULL, MS_BIND|MS_REC, NULL) < 0)
errExit("mount bind");
// mount tmpfs on /tmp
if (arg_debug)
printf("Mounting tmpfs on /tmp directory\n");
if (mount("tmpfs", "/tmp", "tmpfs", MS_NOSUID | MS_STRICTATIME | MS_REC, "mode=777,gid=0") < 0)
errExit("mounting tmpfs on /tmp");
}
// /media mountpoint
if (media_dir) {
// keep a copy of real /media directory in WHITELIST_MEDIA_DIR
int rv = mkdir(WHITELIST_MEDIA_DIR, S_IRWXU | S_IRWXG | S_IRWXO);
if (rv == -1)
errExit("mkdir");
if (chown(WHITELIST_MEDIA_DIR, 0, 0) < 0)
errExit("chown");
if (chmod(WHITELIST_MEDIA_DIR, 0755) < 0)
errExit("chmod");
if (mount("/media", WHITELIST_MEDIA_DIR, NULL, MS_BIND|MS_REC, NULL) < 0)
errExit("mount bind");
// mount tmpfs on /media
if (arg_debug)
printf("Mounting tmpfs on /media directory\n");
if (mount("tmpfs", "/media", "tmpfs", MS_NOSUID | MS_STRICTATIME | MS_REC, "mode=755,gid=0") < 0)
errExit("mounting tmpfs on /media");
}
// /media mountpoint
if (var_dir) {
// keep a copy of real /var directory in WHITELIST_VAR_DIR
int rv = mkdir(WHITELIST_VAR_DIR, S_IRWXU | S_IRWXG | S_IRWXO);
if (rv == -1)
errExit("mkdir");
if (chown(WHITELIST_VAR_DIR, 0, 0) < 0)
errExit("chown");
if (chmod(WHITELIST_VAR_DIR, 0755) < 0)
errExit("chmod");
if (mount("/var", WHITELIST_VAR_DIR, NULL, MS_BIND|MS_REC, NULL) < 0)
errExit("mount bind");
// mount tmpfs on /var
if (arg_debug)
printf("Mounting tmpfs on /var directory\n");
if (mount("tmpfs", "/var", "tmpfs", MS_NOSUID | MS_STRICTATIME | MS_REC, "mode=755,gid=0") < 0)
errExit("mounting tmpfs on /var");
}
// /dev mountpoint
if (dev_dir) {
// keep a copy of real /dev directory in WHITELIST_DEV_DIR
int rv = mkdir(WHITELIST_DEV_DIR, S_IRWXU | S_IRWXG | S_IRWXO);
if (rv == -1)
errExit("mkdir");
if (chown(WHITELIST_DEV_DIR, 0, 0) < 0)
errExit("chown");
if (chmod(WHITELIST_DEV_DIR, 0755) < 0)
errExit("chmod");
if (mount("/dev", WHITELIST_DEV_DIR, NULL, MS_BIND|MS_REC, NULL) < 0)
errExit("mount bind");
// mount tmpfs on /var
if (arg_debug)
printf("Mounting tmpfs on /dev directory\n");
if (mount("tmpfs", "/dev", "tmpfs", MS_NOSUID | MS_STRICTATIME | MS_REC, "mode=755,gid=0") < 0)
errExit("mounting tmpfs on /dev");
}
// go through profile rules again, and interpret whitelist commands
entry = cfg.profile;
while (entry) {
// handle only whitelist commands
if (strncmp(entry->data, "whitelist ", 10)) {
entry = entry->next;
continue;
}
//printf("here %d#%s#\n", __LINE__, entry->data);
// whitelist the real file
whitelist_path(entry);
// create the link if any
if (entry->link) {
// if the link is already there, do not bother
struct stat s;
if (stat(entry->link, &s) != 0) {
int rv = symlink(entry->data + 10, entry->link);
if (rv)
fprintf(stderr, "Warning cannot create symbolic link %s\n", entry->link);
else if (arg_debug)
printf("Created symbolic link %s -> %s\n", entry->link, entry->data + 10);
}
}
entry = entry->next;
}
// mask the real home directory, currently mounted on WHITELIST_HOME_DIR
if (home_dir) {
if (mount("tmpfs", WHITELIST_HOME_DIR, "tmpfs", MS_NOSUID | MS_STRICTATIME | MS_REC, "mode=755,gid=0") < 0)
errExit("mount tmpfs");
}
// mask the real /tmp directory, currently mounted on WHITELIST_TMP_DIR
if (tmp_dir) {
if (mount("tmpfs", WHITELIST_TMP_DIR, "tmpfs", MS_NOSUID | MS_STRICTATIME | MS_REC, "mode=755,gid=0") < 0)
errExit("mount tmpfs");
}
return;
errexit:
fprintf(stderr, "Error: invalid whitelist path %s\n", new_name);
exit(1);
}
static void sanitize_passwd(void) {
struct stat s;
if (stat("/etc/passwd", &s) == -1)
return;
if (arg_debug)
printf("Sanitizing /etc/passwd, UID_MIN %d\n", UID_MIN);
if (is_link("/etc/passwd")) {
fprintf(stderr, "Error: invalid /etc/passwd\n");
exit(1);
}
FILE *fpin = NULL;
FILE *fpout = NULL;
fs_build_mnt_dir();
// open files
/* coverity[toctou] */
fpin = fopen("/etc/passwd", "r");
if (!fpin)
goto errout;
fpout = fopen(RUN_PASSWD_FILE, "w");
if (!fpout)
goto errout;
// read the file line by line
char buf[MAXBUF];
uid_t myuid = getuid();
while (fgets(buf, MAXBUF, fpin)) {
// comments and empty lines
if (*buf == '\0' || *buf == '#')
continue;
// sample line:
// www-data:x:33:33:www-data:/var/www:/bin/sh
// drop lines with uid > 1000 and not the current user
char *ptr = buf;
// advance to uid
while (*ptr != ':' && *ptr != '\0')
ptr++;
if (*ptr == '\0')
goto errout;
char *ptr1 = ptr;
ptr++;
while (*ptr != ':' && *ptr != '\0')
ptr++;
if (*ptr == '\0')
goto errout;
ptr++;
if (*ptr == '\0')
goto errout;
// process uid
int uid;
int rv = sscanf(ptr, "%d:", &uid);
if (rv == 0 || uid < 0)
goto errout;
if (uid < UID_MIN) {
fprintf(fpout, "%s", buf);
continue;
}
if ((uid_t) uid != myuid) {
// store user name - necessary to process /etc/group
*ptr1 = '\0';
char *user = strdup(buf);
if (!user)
errExit("malloc");
ulist_add(user);
continue; // skip line
}
fprintf(fpout, "%s", buf);
}
fclose(fpin);
fclose(fpout);
if (chown(RUN_PASSWD_FILE, 0, 0) == -1)
errExit("chown");
if (chmod(RUN_PASSWD_FILE, 0644) == -1)
errExit("chmod");
// mount-bind tne new password file
if (mount(RUN_PASSWD_FILE, "/etc/passwd", "none", MS_BIND, "mode=400,gid=0") < 0)
errExit("mount");
fs_logger("create /etc/passwd");
return;
errout:
fprintf(stderr, "Warning: failed to clean up /etc/passwd\n");
if (fpin)
fclose(fpin);
if (fpout)
fclose(fpout);
}
void fs_overlayfs(void) {
// check kernel version
struct utsname u;
int rv = uname(&u);
if (rv != 0)
errExit("uname");
int major;
int minor;
if (2 != sscanf(u.release, "%d.%d", &major, &minor)) {
fprintf(stderr, "Error: cannot extract Linux kernel version: %s\n", u.version);
exit(1);
}
if (arg_debug)
printf("Linux kernel version %d.%d\n", major, minor);
int oldkernel = 0;
if (major < 3) {
fprintf(stderr, "Error: minimum kernel version required 3.x\n");
exit(1);
}
if (major == 3 && minor < 18)
oldkernel = 1;
// build overlay directories
fs_build_mnt_dir();
char *oroot;
if(asprintf(&oroot, "%s/oroot", MNT_DIR) == -1)
errExit("asprintf");
if (mkdir(oroot, S_IRWXU | S_IRWXG | S_IRWXO))
errExit("mkdir");
if (chown(oroot, 0, 0) < 0)
errExit("chown");
if (chmod(oroot, S_IRWXU | S_IRGRP | S_IXGRP | S_IROTH | S_IXOTH) < 0)
errExit("chmod");
char *odiff;
if(asprintf(&odiff, "%s/odiff", MNT_DIR) == -1)
errExit("asprintf");
if (mkdir(odiff, S_IRWXU | S_IRWXG | S_IRWXO))
errExit("mkdir");
if (chown(odiff, 0, 0) < 0)
errExit("chown");
if (chmod(odiff, S_IRWXU | S_IRGRP | S_IXGRP | S_IROTH | S_IXOTH) < 0)
errExit("chmod");
char *owork;
if(asprintf(&owork, "%s/owork", MNT_DIR) == -1)
errExit("asprintf");
if (mkdir(owork, S_IRWXU | S_IRWXG | S_IRWXO))
errExit("mkdir");
if (chown(owork, 0, 0) < 0)
errExit("chown");
if (chmod(owork, S_IRWXU | S_IRGRP | S_IXGRP | S_IROTH | S_IXOTH) < 0)
errExit("chmod");
// mount overlayfs
if (arg_debug)
printf("Mounting OverlayFS\n");
char *option;
if (oldkernel) { // old Ubuntu/OpenSUSE kernels
if (asprintf(&option, "lowerdir=/,upperdir=%s", odiff) == -1)
errExit("asprintf");
if (mount("overlayfs", oroot, "overlayfs", MS_MGC_VAL, option) < 0)
errExit("mounting overlayfs");
}
else { // kernel 3.18 or newer
if (asprintf(&option, "lowerdir=/,upperdir=%s,workdir=%s", odiff, owork) == -1)
errExit("asprintf");
if (mount("overlay", oroot, "overlay", MS_MGC_VAL, option) < 0)
errExit("mounting overlayfs");
}
// mount-bind dev directory
if (arg_debug)
printf("Mounting /dev\n");
char *dev;
if (asprintf(&dev, "%s/dev", oroot) == -1)
errExit("asprintf");
if (mount("/dev", dev, NULL, MS_BIND|MS_REC, NULL) < 0)
errExit("mounting /dev");
// chroot in the new filesystem
if (chroot(oroot) == -1)
errExit("chroot");
// update /var directory in order to support multiple sandboxes running on the same root directory
if (!arg_private_dev)
fs_dev_shm();
fs_var_lock();
fs_var_tmp();
fs_var_log();
fs_var_lib();
fs_var_cache();
fs_var_utmp();
// only in user mode
if (getuid())
sanitize_home();
// cleanup and exit
free(option);
free(oroot);
free(odiff);
}
// disable shm in pulseaudio
void pulseaudio_init(void) {
struct stat s;
// do we have pulseaudio in the system?
if (stat("/etc/pulse/client.conf", &s) == -1)
return;
// create the new user pulseaudio directory
fs_build_mnt_dir();
int rv = mkdir(RUN_PULSE_DIR, 0700);
(void) rv; // in --chroot mode the directory can already be there
if (chown(RUN_PULSE_DIR, getuid(), getgid()) < 0)
errExit("chown");
if (chmod(RUN_PULSE_DIR, 0700) < 0)
errExit("chmod");
// create the new client.conf file
char *pulsecfg = NULL;
if (asprintf(&pulsecfg, "%s/client.conf", RUN_PULSE_DIR) == -1)
errExit("asprintf");
if (copy_file("/etc/pulse/client.conf", pulsecfg))
errExit("copy_file");
FILE *fp = fopen(pulsecfg, "a+");
if (!fp)
errExit("fopen");
fprintf(fp, "%s", "\nenable-shm = no\n");
fclose(fp);
if (chmod(pulsecfg, 0644) == -1)
errExit("chmod");
if (chown(pulsecfg, getuid(), getgid()) == -1)
errExit("chown");
// create ~/.config/pulse directory if not present
char *dir1;
if (asprintf(&dir1, "%s/.config", cfg.homedir) == -1)
errExit("asprintf");
if (stat(dir1, &s) == -1) {
int rv = mkdir(dir1, 0755);
if (rv == 0) {
rv = chown(dir1, getuid(), getgid());
(void) rv;
rv = chmod(dir1, 0755);
(void) rv;
}
}
free(dir1);
if (asprintf(&dir1, "%s/.config/pulse", cfg.homedir) == -1)
errExit("asprintf");
if (stat(dir1, &s) == -1) {
int rv = mkdir(dir1, 0700);
if (rv == 0) {
rv = chown(dir1, getuid(), getgid());
(void) rv;
rv = chmod(dir1, 0700);
(void) rv;
}
}
free(dir1);
// if we have ~/.config/pulse mount the new directory, else set environment variable
char *homeusercfg;
if (asprintf(&homeusercfg, "%s/.config/pulse", cfg.homedir) == -1)
errExit("asprintf");
if (stat(homeusercfg, &s) == 0) {
if (mount(RUN_PULSE_DIR, homeusercfg, "none", MS_BIND, NULL) < 0)
errExit("mount pulseaudio");
fs_logger2("tmpfs", homeusercfg);
}
else {
// set environment
if (setenv("PULSE_CLIENTCONFIG", pulsecfg, 1) < 0)
errExit("setenv");
}
free(pulsecfg);
free(homeusercfg);
}
// private mode (--private-home=list):
// mount homedir on top of /home/user,
// tmpfs on top of /root in nonroot mode,
// tmpfs on top of /tmp in root mode,
// set skel files,
// restore .Xauthority
void fs_private_home_list(void) {
char *homedir = cfg.homedir;
char *private_list = cfg.home_private_keep;
assert(homedir);
assert(private_list);
int xflag = store_xauthority();
uid_t u = getuid();
gid_t g = getgid();
struct stat s;
if (stat(homedir, &s) == -1) {
exechelp_logerrv("firejail", FIREJAIL_ERROR, "Error: cannot find user home directory\n");
exit(1);
}
// create /tmp/firejail/mnt/home directory
fs_build_mnt_dir();
int rv = mkdir(HOME_DIR, S_IRWXU | S_IRWXG | S_IRWXO);
if (rv == -1)
errExit("mkdir");
if (chown(HOME_DIR, u, g) < 0)
errExit("chown");
if (chmod(HOME_DIR, 0755) < 0)
errExit("chmod");
// copy the list of files in the new home directory
// using a new child process without root privileges
pid_t child = fork();
if (child < 0)
errExit("fork");
if (child == 0) {
if (arg_debug)
printf("Copying files in the new home:\n");
// drop privileges
if (setgroups(0, NULL) < 0)
errExit("setgroups");
if (setgid(getgid()) < 0)
errExit("setgid/getgid");
if (setuid(getuid()) < 0)
errExit("setuid/getuid");
// copy the list of files in the new home directory
char *dlist = strdup(cfg.home_private_keep);
if (!dlist)
errExit("strdup");
char *ptr = strtok(dlist, ",");
duplicate(ptr);
while ((ptr = strtok(NULL, ",")) != NULL)
duplicate(ptr);
free(dlist);
exit(0);
}
// wait for the child to finish
waitpid(child, NULL, 0);
// mount bind private_homedir on top of homedir
char *newhome;
if (asprintf(&newhome, "%s%s", HOME_DIR, cfg.homedir) == -1)
errExit("asprintf");
if (arg_debug)
printf("Mount-bind %s on top of %s\n", newhome, homedir);
if (mount(newhome, homedir, NULL, MS_BIND|MS_REC, NULL) < 0)
errExit("mount bind");
// preserve mode and ownership
// if (chown(homedir, s.st_uid, s.st_gid) == -1)
// errExit("mount-bind chown");
// if (chmod(homedir, s.st_mode) == -1)
// errExit("mount-bind chmod");
if (u != 0) {
// mask /root
if (arg_debug)
printf("Mounting a new /root directory\n");
if (mount("tmpfs", "/root", "tmpfs", MS_NOSUID | MS_NODEV | MS_STRICTATIME | MS_REC, "mode=700,gid=0") < 0)
errExit("mounting home directory");
}
else {
// mask /home
if (arg_debug)
printf("Mounting a new /home directory\n");
if (mount("tmpfs", "/home", "tmpfs", MS_NOSUID | MS_NODEV | MS_STRICTATIME | MS_REC, "mode=755,gid=0") < 0)
errExit("mounting home directory");
// mask /tmp only in root mode; KDE keeps all kind of sockets in /tmp!
if (arg_debug)
printf("Mounting a new /tmp directory\n");
if (mount("tmpfs", "/tmp", "tmpfs", MS_NOSUID | MS_NODEV | MS_STRICTATIME | MS_REC, "mode=777,gid=0") < 0)
errExit("mounting tmp directory");
}
skel(homedir, u, g);
if (xflag)
copy_xauthority();
}
void fs_private_dev(void){
int rv;
// install a new /dev directory
if (arg_debug)
printf("Mounting tmpfs on /dev\n");
int have_dri = 0;
struct stat s;
if (stat("/dev/dri", &s) == 0)
have_dri = 1;
// create DRI_DIR
fs_build_mnt_dir();
if (have_dri) {
/* coverity[toctou] */
rv = mkdir(RUN_DRI_DIR, 0755);
if (rv == -1)
errExit("mkdir");
if (chown(RUN_DRI_DIR, 0, 0) < 0)
errExit("chown");
if (chmod(RUN_DRI_DIR, 0755) < 0)
errExit("chmod");
// keep a copy of /dev/dri under DRI_DIR
if (mount("/dev/dri", RUN_DRI_DIR, NULL, MS_BIND|MS_REC, NULL) < 0)
errExit("mounting /dev/dri");
}
// restore /dev/log
int have_devlog = 0;
if (stat("/dev/log", &s) == 0) {
have_devlog = 1;
FILE *fp = fopen(RUN_DEVLOG_FILE, "w");
if (!fp)
have_devlog = 0;
else {
fprintf(fp, "\n");
fclose(fp);
if (mount("/dev/log", RUN_DEVLOG_FILE, NULL, MS_BIND|MS_REC, NULL) < 0)
errExit("mounting /dev/log");
}
}
// mount tmpfs on top of /dev
if (mount("tmpfs", "/dev", "tmpfs", MS_NOSUID | MS_STRICTATIME | MS_REC, "mode=777,gid=0") < 0)
errExit("mounting /dev");
fs_logger("mount tmpfs on /dev");
// bring back /dev/log
if (have_devlog) {
FILE *fp = fopen("/dev/log", "w");
if (fp) {
fprintf(fp, "\n");
fclose(fp);
if (mount(RUN_DEVLOG_FILE, "/dev/log", NULL, MS_BIND|MS_REC, NULL) < 0)
errExit("mounting /dev/log");
fs_logger("clone /dev/log");
}
}
// bring back the /dev/dri directory
if (have_dri) {
/* coverity[toctou] */
rv = mkdir("/dev/dri", 0755);
if (rv == -1)
errExit("mkdir");
if (chown("/dev/dri", 0, 0) < 0)
errExit("chown");
if (chmod("/dev/dri",0755) < 0)
errExit("chmod");
if (mount(RUN_DRI_DIR, "/dev/dri", NULL, MS_BIND|MS_REC, NULL) < 0)
errExit("mounting /dev/dri");
fs_logger("clone /dev/dri");
}
// create /dev/shm
if (arg_debug)
printf("Create /dev/shm directory\n");
rv = mkdir("/dev/shm", 0777);
if (rv == -1)
errExit("mkdir");
if (chown("/dev/shm", 0, 0) < 0)
errExit("chown");
if (chmod("/dev/shm", 0777) < 0)
errExit("chmod");
fs_logger("mkdir /dev/shm");
// create devices
create_char_dev("/dev/zero", 0666, 1, 5); // mknod -m 666 /dev/zero c 1 5
fs_logger("mknod /dev/zero");
create_char_dev("/dev/null", 0666, 1, 3); // mknod -m 666 /dev/null c 1 3
fs_logger("mknod /dev/null");
create_char_dev("/dev/full", 0666, 1, 7); // mknod -m 666 /dev/full c 1 7
fs_logger("mknod /dev/full");
create_char_dev("/dev/random", 0666, 1, 8); // Mknod -m 666 /dev/random c 1 8
fs_logger("mknod /dev/random");
create_char_dev("/dev/urandom", 0666, 1, 9); // mknod -m 666 /dev/urandom c 1 9
fs_logger("mknod /dev/urandom");
create_char_dev("/dev/tty", 0666, 5, 0); // mknod -m 666 /dev/tty c 5 0
fs_logger("mknod /dev/tty");
#if 0
create_dev("/dev/tty0", "mknod -m 666 /dev/tty0 c 4 0");
create_dev("/dev/console", "mknod -m 622 /dev/console c 5 1");
#endif
// pseudo-terminal
rv = mkdir("/dev/pts", 0755);
if (rv == -1)
errExit("mkdir");
if (chown("/dev/pts", 0, 0) < 0)
errExit("chown");
if (chmod("/dev/pts", 0755) < 0)
errExit("chmod");
fs_logger("mkdir /dev/pts");
create_char_dev("/dev/pts/ptmx", 0666, 5, 2); //"mknod -m 666 /dev/pts/ptmx c 5 2");
fs_logger("mknod /dev/pts/ptmx");
create_link("/dev/pts/ptmx", "/dev/ptmx");
// mount -vt devpts -o newinstance -o ptmxmode=0666 devpts //dev/pts
if (mount("devpts", "/dev/pts", "devpts", MS_MGC_VAL, "newinstance,ptmxmode=0666") < 0)
errExit("mounting /dev/pts");
fs_logger("mount devpts");
#if 0
// stdin, stdout, stderr
create_link("/proc/self/fd", "/dev/fd");
create_link("/proc/self/fd/0", "/dev/stdin");
create_link("/proc/self/fd/1", "/dev/stdout");
create_link("/proc/self/fd/2", "/dev/stderr");
#endif
}
static void sanitize_group(void) {
struct stat s;
if (stat("/etc/group", &s) == -1)
return;
if (arg_debug)
printf("Sanitizing /etc/group, GID_MIN %d\n", GID_MIN);
if (is_link("/etc/group")) {
fprintf(stderr, "Error: invalid /etc/group\n");
exit(1);
}
FILE *fpin = NULL;
FILE *fpout = NULL;
fs_build_mnt_dir();
// open files
/* coverity[toctou] */
fpin = fopen("/etc/group", "r");
if (!fpin)
goto errout;
fpout = fopen(RUN_GROUP_FILE, "w");
if (!fpout)
goto errout;
// read the file line by line
char buf[MAXBUF];
gid_t mygid = getgid();
while (fgets(buf, MAXBUF, fpin)) {
// comments and empty lines
if (*buf == '\0' || *buf == '#')
continue;
// sample line:
// pulse:x:115:netblue,bingo
// drop lines with uid > 1000 and not the current user group
char *ptr = buf;
// advance to uid
while (*ptr != ':' && *ptr != '\0')
ptr++;
if (*ptr == '\0')
goto errout;
ptr++;
while (*ptr != ':' && *ptr != '\0')
ptr++;
if (*ptr == '\0')
goto errout;
ptr++;
if (*ptr == '\0')
goto errout;
// process uid
int gid;
int rv = sscanf(ptr, "%d:", &gid);
if (rv == 0 || gid < 0)
goto errout;
if (gid < GID_MIN) {
if (copy_line(fpout, buf, ptr))
goto errout;
continue;
}
if ((gid_t) gid != mygid) {
continue; // skip line
}
if (copy_line(fpout, buf, ptr))
goto errout;
}
fclose(fpin);
fclose(fpout);
if (chown(RUN_GROUP_FILE, 0, 0) == -1)
errExit("chown");
if (chmod(RUN_GROUP_FILE, 0644) == -1)
errExit("chmod");
// mount-bind tne new group file
if (mount(RUN_GROUP_FILE, "/etc/group", "none", MS_BIND, "mode=400,gid=0") < 0)
errExit("mount");
fs_logger("create /etc/group");
return;
errout:
fprintf(stderr, "Warning: failed to clean up /etc/group\n");
if (fpin)
fclose(fpin);
if (fpout)
fclose(fpout);
}
static void fs_build_remount_mnt_dir(void) {
tmpfs_mounted = 0;
fs_build_mnt_dir();
}