10 Commits

Author SHA1 Message Date
78e108d0d4 Added more tests 2025-05-06 17:56:55 +02:00
b4149ac425 Updated gitignore 2025-05-06 12:19:39 +02:00
6065a0c20a Added permissions globbing tests 2025-05-06 12:18:45 +02:00
15fa0fe193 Added filename return to the dialogue mockup 2025-05-06 12:18:21 +02:00
801a7cdb39 Added temp permission globbing 2025-05-06 12:17:50 +02:00
22b091f017 Fixed empty filename bug. 2025-05-06 12:17:26 +02:00
fd2144a1f9 Added a filename check 2025-05-05 18:59:57 +02:00
420f34a7f3 Added folder globbing for permanent permissions 2025-05-05 18:53:05 +02:00
4539df9842 Fixed wrong fallback filename bug 2025-05-04 17:39:39 +02:00
e32ce5add5 Renamed all zenity mentions to dialogue 2025-05-04 17:25:47 +02:00
11 changed files with 309 additions and 148 deletions

4
.gitignore vendored
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@@ -2,13 +2,13 @@ build/*
.clang-tidy
.cache
test/protected/*
test/.pt.db
*compile_commands.json
test/perf*
test/callgraph*
test/openers
test/opener/opener
test/opener/opener.o
test/.*
*compile_commands.json
src/gui/ui/*
src/gui/*.o
src/gui/icfs_dialogue

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@@ -70,7 +70,7 @@ default: $(TARGETS)
$(BUILD_DIR)/icfs_dialogue:
make -C $(SOURCES_DIR)/gui TEST=$(TEST) DEBUG=$(shell realpath $(DEBUG)) SOURCES_DIR=$(shell realpath $(SOURCES_DIR)/gui) BUILD_DIR=$(shell realpath $(BUILD_DIR)) TESTS_DIR=$(shell realpath $(TESTS_DIR))
$(BUILD_DIR)/icfs: $(BUILD_DIR)/main.o $(BUILD_DIR)/fuse_operations.o $(BUILD_DIR)/sourcefs.o $(BUILD_DIR)/ui-socket.o $(BUILD_DIR)/temp_permissions_table.o $(BUILD_DIR)/perm_permissions_table.o
$(BUILD_DIR)/icfs: $(BUILD_DIR)/main.o $(BUILD_DIR)/fuse_operations.o $(BUILD_DIR)/sourcefs.o $(BUILD_DIR)/ui-socket.o $(BUILD_DIR)/temp_permissions_table.o $(BUILD_DIR)/perm_permissions_table.o $(BUILD_DIR)/proc_operations.o
$(CC) $(CFLAGS) $^ $(LDFLAGS) -o $(BUILD_DIR)/icfs
icfs_test: $(BUILD_DIR)/icfs
@@ -97,6 +97,9 @@ $(BUILD_DIR)/temp_permissions_table.o: $(SOURCES_DIR)/temp_permissions_table.c $
$(BUILD_DIR)/perm_permissions_table.o: $(SOURCES_DIR)/perm_permissions_table.c $(SOURCES_DIR)/perm_permissions_table.h
$(CC) $(CFLAGS) -c $< $(LDFLAGS) -o $@
$(BUILD_DIR)/proc_operations.o: $(SOURCES_DIR)/proc_operations.c $(SOURCES_DIR)/proc_operations.h
$(CC) $(CFLAGS) -c $< $(LDFLAGS) -o $@
CLEAN_TARGETS=clean-icfs
ifneq ($(DIALOGUE), 0)

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@@ -39,63 +39,10 @@
#include <sys/file.h> /* flock(2) */
#include "fuse_operations.h"
#include "proc_operations.h"
#include "sourcefs.h"
#include "ui-socket.h"
char *get_process_name_by_pid(const int pid) {
char path[1024];
sprintf(path, "/proc/%d/exe", pid);
char *name = realpath(path, NULL);
if (name == NULL) {
fprintf(stderr, "Could not get process name by pid %d", pid);
perror("");
}
/*
size_t namelen = 32;
ssize_t readret = 0;
char *name = NULL;
while (namelen >= (size_t)readret && readret > 0) {
namelen *= 2;
name = calloc(namelen, sizeof(char));
if (name == NULL) {
free(path);
fprintf(stderr, "Could not get get process name by pid %d", pid);
perror("");
return NULL;
}
readret = readlink(path, name, namelen);
if (readret < 0) {
free(name);
free(path);
fprintf(stderr, "Couldn't get process name by pid %d", pid);
perror("");
return NULL;
}
if (namelen >= (size_t)readret) {
free(name);
}
}
*/
return name;
/*
FILE *file = fopen(path, "r");
if (file) {
size_t size = 0;
size = fread(path, sizeof(char), 1024, file);
if (size > 0) {
if ('\n' == path[size - 1]) {
path[size - 1] = '\0';
}
}
fclose(file);
}
*/
}
static void *xmp_init(struct fuse_conn_info *conn, struct fuse_config *cfg) {
(void)conn;
cfg->use_ino = 1;

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@@ -8,6 +8,7 @@
#include "perm_permissions_table.h"
#include "access_t.h"
#include "proc_operations.h"
#include "process_info.h"
#include "set_mode_t.h"
#include <fcntl.h>
@@ -204,13 +205,16 @@ void destroy_perm_permissions_table(void) { sqlite3_close(perm_database); }
* @return: access status - ALLOW, DENY or NDEF in case if no information was
* found
*/
access_t check_perm_access(const char *filename, struct process_info pi) {
access_t check_perm_access_noparent(const char *filename,
struct process_info pi) {
char *query = NULL;
int ret = asprintf(&query,
"SELECT * FROM %s WHERE executable = \'%s\' "
"AND filename = \'%s\';",
table_name, pi.name, filename);
"AND ((\'%s\' LIKE CONCAT(filename, \'%%\') AND filename "
"GLOB \'*/\') OR filename = \'%s\');",
table_name, pi.name, filename, filename);
fprintf(stderr, "query: %s\n", query);
if (ret < 0) {
// If asprintf fails, the contents of query are undefined (see man
@@ -241,6 +245,45 @@ access_t check_perm_access(const char *filename, struct process_info pi) {
return NDEF;
}
/**
* Checks if the process or any of it's parents have permanent access to the
* file.
*
* @param filename: The file that the process is trying to access
* @pram pi: The process information
* @return: access status - ALLOW, DENY or NDEF in case if no information was
* found. Does not return ALLOW_TEMP or DENY_TEMP.
* @note: In case one of the parent processes is killed while this function
* execution the result is not guranteed to be correct. It should only lead to
* false negatives, though.
*/
access_t check_perm_access(const char *filename, struct process_info pi) {
if (pi.PID == 0) {
return NDEF;
}
struct process_info current_pi = pi;
current_pi.name = strdup(current_pi.name);
while (current_pi.PID != 0) {
access_t access = check_perm_access_noparent(filename, current_pi);
free(current_pi.name);
if (access != NDEF) {
return access;
}
current_pi.name = NULL;
while (current_pi.name == NULL) {
current_pi.PID = get_parent_pid(current_pi.PID);
if (current_pi.PID != 0) {
current_pi.name = get_process_name_by_pid(current_pi.PID);
} else {
break;
}
}
}
return NDEF;
}
/**
* Gives permanent access to the process to the file.
*

45
src/proc_operations.c Normal file
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@@ -0,0 +1,45 @@
#include "proc_operations.h"
#include <stdio.h>
#include <stdlib.h>
char *get_process_name_by_pid(const int pid) {
char path[1024];
sprintf(path, "/proc/%d/exe", pid);
char *name = realpath(path, NULL);
if (name == NULL) {
fprintf(stderr, "Could not get process name by pid %d", pid);
perror("");
}
return name;
}
/**
* Finds the parent process ID of a given process.
*
* @param pid: The process ID of the process to find the parent of
* @return: The parent process ID, or 0 if the parent process ID could not be
* found
*/
pid_t get_parent_pid(pid_t pid) {
pid_t ppid = 0;
char path[256];
snprintf(path, sizeof(path), "/proc/%u/status", pid);
FILE *file = fopen(path, "r");
if (file == NULL) {
perror("Failed to open /proc/<pid>/status");
return 0;
}
char line[256];
while (fgets(line, sizeof(line), file)) {
if (sscanf(line, "PPid:\t%d", &ppid) == 1) {
fclose(file);
return ppid;
}
}
fclose(file);
return 0; // Parent PID not found
}

17
src/proc_operations.h Normal file
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@@ -0,0 +1,17 @@
#ifndef PROC_OPERATIONS
#define PROC_OPERATIONS
#include <time.h>
char *get_process_name_by_pid(const int pid);
/**
* Finds the parent process ID of a given process.
*
* @param pid: The process ID of the process to find the parent of
* @return: The parent process ID, or 0 if the parent process ID could not be
* found
*/
pid_t get_parent_pid(pid_t pid);
#endif // !PROC_OPERATIONS

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@@ -9,9 +9,12 @@
#include "temp_permissions_table.h"
#include "access_t.h"
#include "cc.h"
#include "proc_operations.h"
#include "process_info.h"
#include <pthread.h>
#include <stddef.h>
#include <stdio.h>
#include <string.h>
#include <sys/types.h>
struct temp_process_permissions {
@@ -126,14 +129,23 @@ access_t check_temp_access_noparent(const char *filename, pid_t pid) {
if (process_creation_time == permission_entry->creation_time) {
// the process is the same as the one that was granted temporary access
// to the file
size_t filename_len = strlen(filename);
for_each(&permission_entry->denied_files, denied_file) {
if (strncmp(*denied_file, filename, strlen(filename)) == 0) {
size_t denied_file_len = strlen(*denied_file);
if (strncmp(*denied_file, filename, denied_file_len) == 0 &&
((denied_file_len < filename_len &&
(*denied_file)[denied_file_len - 1] == '/') ||
(denied_file_len == filename_len))) {
pthread_mutex_unlock(&temp_permissions_table_lock);
return DENY;
}
}
for_each(&permission_entry->allowed_files, allowed_file) {
if (strncmp(*allowed_file, filename, strlen(filename)) == 0) {
size_t allowed_file_len = strlen(*allowed_file);
if (strncmp(*allowed_file, filename, allowed_file_len) == 0 &&
((allowed_file_len < filename_len &&
(*allowed_file)[allowed_file_len - 1] == '/') ||
(allowed_file_len == filename_len))) {
pthread_mutex_unlock(&temp_permissions_table_lock);
return ALLOW;
}
@@ -144,36 +156,6 @@ access_t check_temp_access_noparent(const char *filename, pid_t pid) {
return NDEF;
}
/**
* Finds the parent process ID of a given process.
*
* @param pid: The process ID of the process to find the parent of
* @return: The parent process ID, or 0 if the parent process ID could not be
* found
*/
pid_t get_parent_pid(pid_t pid) {
pid_t ppid = 0;
char path[256];
snprintf(path, sizeof(path), "/proc/%u/status", pid);
FILE *file = fopen(path, "r");
if (file == NULL) {
perror("Failed to open /proc/<pid>/status");
return 0;
}
char line[256];
while (fgets(line, sizeof(line), file)) {
if (sscanf(line, "PPid:\t%d", &ppid) == 1) {
fclose(file);
return ppid;
}
}
fclose(file);
return 0; // Parent PID not found
}
/**
* Checks if the process or any of it's parents have temporary access to the
* file.

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@@ -26,9 +26,9 @@
#include <sys/un.h>
#include <unistd.h>
#define ZENITY_YES 0
#define ZENITY_NO 1
#define ZENITY_PERM 2
#define DIALOGUE_YES 0
#define DIALOGUE_NO 1
#define DIALOGUE_PERM 2
struct dialogue_response {
access_t decision;
@@ -48,7 +48,7 @@ int init_ui_socket(const char *perm_permissions_db_filename) {
return 1;
}
// Test if Zenity is installed (get version)
// Test if dialogue is installed (get version)
fp = popen("icfs_dialogue --version", "r");
if (fp == NULL) {
perror("Pipe returned an error");
@@ -93,12 +93,12 @@ struct dialogue_response ask_access(const char *filename,
perror("");
response.decision = DENY;
response.filename = malloc(2);
response.filename[0] = '.';
response.filename[0] = '/';
response.filename[1] = 0;
return response;
}
// Zenity Question Message Popup
// dialogue Question Message Popup
fp = popen(command, "r");
free(command);
@@ -106,43 +106,43 @@ struct dialogue_response ask_access(const char *filename,
perror("Pipe returned a error");
response.decision = DENY;
response.filename = malloc(2);
response.filename[0] = '.';
response.filename[0] = '/';
response.filename[1] = 0;
return response;
}
str(char) zenity_output;
init(&zenity_output);
str(char) dialogue_output;
init(&dialogue_output);
char line[1024]; // Buffer to read individual lines
// Read the command output line by line
while (fgets(line, sizeof(line), fp)) {
push_fmt(&zenity_output, line);
push_fmt(&dialogue_output, line);
}
int zenity_exit_code = WEXITSTATUS(pclose(fp));
fprintf(stderr, "zenity wrote out %s\n", first(&zenity_output));
fprintf(stderr, "zenity returned %d\n", zenity_exit_code);
int dialogue_exit_code = WEXITSTATUS(pclose(fp));
fprintf(stderr, "dialogue wrote out %s\n", first(&dialogue_output));
fprintf(stderr, "dialogue returned %d\n", dialogue_exit_code);
// if (size(&zenity_output) == 0) {
// push(&zenity_output, '.');
// }
if (size(&dialogue_output) == 0) {
push(&dialogue_output, '/');
}
assert(strlen(first(&zenity_output)) == size(&zenity_output));
assert(strlen(first(&dialogue_output)) == size(&dialogue_output));
response.filename = malloc(size(&zenity_output) + 1);
strcpy(response.filename, first(&zenity_output));
// response.filename[size(&zenity_output)] = 0;
response.filename = malloc(size(&dialogue_output) + 1);
strcpy(response.filename, first(&dialogue_output));
// response.filename[size(&dialogue_output)] = 0;
// assert(0 == strcmp(response.filename, first(&zenity_output)));
cleanup(&zenity_output);
// assert(0 == strcmp(response.filename, first(&dialogue_output)));
cleanup(&dialogue_output);
if (zenity_exit_code == (ZENITY_YES | ZENITY_PERM)) {
if (dialogue_exit_code == (DIALOGUE_YES | DIALOGUE_PERM)) {
response.decision = ALLOW;
} else if (zenity_exit_code == ZENITY_YES) {
} else if (dialogue_exit_code == DIALOGUE_YES) {
response.decision = ALLOW_TEMP;
} else if (zenity_exit_code == (ZENITY_NO | ZENITY_PERM)) {
} else if (dialogue_exit_code == (DIALOGUE_NO | DIALOGUE_PERM)) {
response.decision = DENY;
} else {
response.decision = DENY_TEMP;
@@ -225,7 +225,6 @@ int interactive_access(const char *filename, struct process_info proc_info,
// the user might specify a different file in the dialogue, so we need to
// check if it is valid
/*
while (source_access(response.filename, F_OK)) {
// if it is invalid, just ask again.
fprintf(stderr, "Filename returned by zenty wasn't correct: %s\n",
@@ -233,7 +232,7 @@ int interactive_access(const char *filename, struct process_info proc_info,
free(response.filename);
response = ask_access(filename, proc_info);
}
*/
free(real_path);
real_path = real_filename(response.filename);

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@@ -1,29 +1,41 @@
#!/bin/bash
# fake-zenity: script that mocks the behavior of zenity based on the ./.fake-zenity-response file
# fake-icfs_dialogue: script that mocks the behavior of icfs_dialogue based on the ./.fake-icfs_dialogue-response file
ZENITY_YES=0
ZENITY_NO=1
ZENITY_PERM=2
ICFS_DIALOGUE_YES=0
ICFS_DIALOGUE_NO=1
ICFS_DIALOGUE_PERM=2
if [[ $1 == "--set-fake-response" ]]; then
#someone knows we are fake :)
echo "$2" >~/.fake_zenity_response
echo "$2" >~/.fake_icfs_dialogue_response
elif [[ $1 == "--set-fake-response-filename" ]]; then
echo "$2" >~/.fake_icfs_dialogue_response_filename
elif [[ $1 == "--reset-fake-response" ]]; then
rm ~/.fake_icfs_dialogue_response ~/.fake_icfs_dialogue_response_filename
else
if [ -f ~/.fake_zenity_response ]; then
FAKE_ZENITY_RESPONSE=$(cat ~/.fake_zenity_response)
if [ -f ~/.fake_icfs_dialogue_response ]; then
FAKE_ICFS_DIALOGUE_RESPONSE=$(cat ~/.fake_icfs_dialogue_response)
printf "%s" "$4"
if [[ $FAKE_ZENITY_RESPONSE == "yes" ]]; then
exit "$ZENITY_YES"
elif [[ $FAKE_ZENITY_RESPONSE == "no" ]]; then
exit "$ZENITY_NO"
elif [[ $FAKE_ZENITY_RESPONSE == "yes_perm" ]]; then
exit "$((ZENITY_YES | ZENITY_PERM))"
elif [[ $FAKE_ZENITY_RESPONSE == "no_perm" ]]; then
exit "$((ZENITY_NO | ZENITY_PERM))"
if [[ -f ~/.fake_icfs_dialogue_response_filename ]]; then
FAKE_ICFS_DIALOGUE_RESPONSE_FILENAME=$(cat ~/.fake_icfs_dialogue_response_filename)
if [[ $FAKE_ICFS_DIALOGUE_RESPONSE_FILENAME == "" ]]; then
printf "%s" "$4"
else
printf "%s" "$(cat ~/.fake_icfs_dialogue_response_filename)"
fi
fi
if [[ $FAKE_ICFS_DIALOGUE_RESPONSE == "yes" ]]; then
exit "$ICFS_DIALOGUE_YES"
elif [[ $FAKE_ICFS_DIALOGUE_RESPONSE == "no" ]]; then
exit "$ICFS_DIALOGUE_NO"
elif [[ $FAKE_ICFS_DIALOGUE_RESPONSE == "yes_perm" ]]; then
exit "$((ICFS_DIALOGUE_YES | ICFS_DIALOGUE_PERM))"
elif [[ $FAKE_ICFS_DIALOGUE_RESPONSE == "no_perm" ]]; then
exit "$((ICFS_DIALOGUE_NO | ICFS_DIALOGUE_PERM))"
fi
fi
fi
exit 255 # TODO: call actual zenity here
exit 255 # TODO: call actual icfs_dialogue here

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@@ -1,20 +1,86 @@
#include <dirent.h>
#include <errno.h>
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <unistd.h>
#define PATH_MAX 4096
int main(int argc, char *argv[]) {
// Check for correct usage
if (argc != 2) {
fprintf(stderr, "Usage: ./opener [FILENAME]");
fprintf(stderr, "Usage: %s <pathname>\n", argv[0]);
return 1;
}
int fd = open(argv[1], O_RDWR | O_CREAT);
if (fd == -1) {
perror("Cannot open file");
const char *path = argv[1];
struct stat statbuf;
// Stat the given path to determine if it's a directory
if (lstat(path, &statbuf) == -1) {
perror("lstat");
return 1;
}
close(fd);
return 0;
// Case 1: The path is not a directory
if (!S_ISDIR(statbuf.st_mode)) {
int fd = open(path, O_RDONLY);
if (fd == -1) {
perror("open");
return 1;
}
close(fd);
return 0;
}
// Case 2: The path is a directory
DIR *dirp = opendir(path);
if (dirp == NULL) {
perror("opendir");
return 1;
}
struct dirent *entry;
int success = 1;
while ((entry = readdir(dirp)) != NULL) {
// Skip . and ..
if (strcmp(entry->d_name, ".") == 0 || strcmp(entry->d_name, "..") == 0) {
continue;
}
// Construct the full path
char fullpath[PATH_MAX];
snprintf(fullpath, PATH_MAX, "%s/%s", path, entry->d_name);
// Stat the entry to check if it's a regular file
struct stat entry_stat;
if (lstat(fullpath, &entry_stat) == -1) {
perror("lstat");
success = 0;
break;
}
// Only process regular files
if (!S_ISREG(entry_stat.st_mode)) {
continue;
}
// Try to open and immediately close the file
int fd = open(fullpath, O_RDONLY);
if (fd == -1) {
perror("open");
success = 0;
break;
}
close(fd);
}
closedir(dirp);
return (success ? 0 : 1);
}

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@@ -9,6 +9,13 @@ touch ./protected/do-not-remove ./protected/should-be-removed ./protected/truth
chmod 777 ./protected/perm777 ./protected/perm000
echo "Free code, free world." >./protected/motto
mkdir protected/haystack
for i in {1..10}; do
touch "./protected/haystack/hay$i"
done
touch ./protected/haystack/needle
echo "Liberty in every line." >./protected/haystack/needle
rm -rf ./openers
mkdir openers
make -C ./opener || (
@@ -151,16 +158,56 @@ openers/symlinked_opener2 ./protected/motto >/dev/null 2>/dev/null &&
echo "[ICFS-TEST]: openers/symlinked_opener2 can read protected/motto despite access being denied!" ||
echo "[ICFS-TEST]: OK" # EACCESS
# test permission globbing
icfs_dialogue --set-fake-response yes
icfs_dialogue --set-fake-response-filename "/"
openers/opener3 ./protected/haystack >/dev/null 2>/dev/null &&
echo "[ICFS-TEST]: OK" ||
echo "[ICFS-TEST]: openers/opener3 cannot read protected/haystack/needle despite access being permitted!" # OK
icfs_dialogue --set-fake-response no
icfs_dialogue --set-fake-response-filename "/"
openers/opener4 ./protected/haystack >/dev/null 2>/dev/null &&
echo "[ICFS-TEST]: openers/opener4 can read files in protected/haystack despite access being denied!" ||
echo "[ICFS-TEST]: OK" # EACCESS
icfs_dialogue --set-fake-response yes_perm
icfs_dialogue --set-fake-response-filename "/"
openers/opener5 ./protected/haystack/needle >/dev/null 2>/dev/null &&
echo "[ICFS-TEST]: OK" ||
echo "[ICFS-TEST]: openers/opener5 cannot read protected/haystack/needle despite access being permitted!" # OK
icfs_dialogue --set-fake-response no # this should be ignored
openers/opener5 ./protected/haystack >/dev/null 2>/dev/null &&
echo "[ICFS-TEST]: OK" ||
echo "[ICFS-TEST]: openers/opener5 cannot read files in protected/haystack despite access being permitted!" # OK
icfs_dialogue --set-fake-response no_perm
icfs_dialogue --set-fake-response-filename "/"
openers/opener6 ./protected/haystack/needle >/dev/null 2>/dev/null &&
echo "[ICFS-TEST]: openers/opener6 can read protected/haystack/needle despite access being denied!" ||
echo "[ICFS-TEST]: OK" # EACCESS
icfs_dialogue --set-fake-response yes # this should be ignored
openers/opener6 ./protected/haystack >/dev/null 2>/dev/null &&
echo "[ICFS-TEST]: openers/opener6 can read files in protected/haystack despite access being denied!" ||
echo "[ICFS-TEST]: OK" # EACCESS
# test database access
if [[ -r "./.pt.db" || -w "./.pt.db" ]]; then
echo "[ICFS-TEST]: permanent permissions is accessible!"
if [[ $1 == '--setuid' ]]; then
if [[ -r "./.pt.db" || -w "./.pt.db" ]]; then
echo "[ICFS-TEST]: permanent permissions database is accessible!"
else
echo "[ICFS-TEST]: OK"
fi
else
echo "[ICFS-TEST]: OK"
echo "[ICFS-TEST]: permanent permissions database access was not tested due to the lack of seuid bit setting capabilites. To test this, run the script with '--setuid' flag"
fi
# unmount
sleep 0.5
#lsof +f -- $(realpath ./protected)
umount $(realpath ./protected)
umount "$(realpath ./protected)"
sleep 0.5