src/fuse_operations.c

@@ -108,29 +108,7 @@ static int xmp_getattr(const char *path, struct stat *stbuf,
 static int xmp_access(const char *path, int mask) {
   int res;
 
-  // if mask is F_OK, then we don't need to check the permissions
+  res = access(path, mask);
-  // (is that possible?)
-
-  if (mask != F_OK) {
-    struct process_info pi;
-    struct fuse_context *fc = fuse_get_context();
-
-    pi.PID = fc->pid;
-    pi.UID = fc->uid;
-    pi.name = get_process_name_by_pid(pi.PID);
-
-    // fprintf(stderr, "%s, %d\n", path, ask_access(path, pi));
-
-    if (!interactive_access(real_filename(path), pi)) {
-      free(pi.name);
-      return -EACCES;
-    }
-
-    free(pi.name);
-  }
-
-  res = source_access(path, mask);
-
   if (res == -1)
     return -errno;
 
@@ -326,30 +304,6 @@ static int xmp_rename(const char *from, const char *to, unsigned int flags) {
   if (flags)
     return -EINVAL;
 
-  struct process_info pi;
-  struct fuse_context *fc = fuse_get_context();
-
-  pi.PID = fc->pid;
-  pi.UID = fc->uid;
-  pi.name = get_process_name_by_pid(pi.PID);
-
-  // fprintf(stderr, "%s, %d\n", path, ask_access(path, pi));
-
-  if (!interactive_access(real_filename(from), pi)) {
-    free(pi.name);
-    return -EACCES;
-  }
-
-  // the "to" file may exist and the process needs to get persmission to modify
-  // it
-  if (source_access(to, F_OK) == 0 &&
-      !interactive_access(real_filename(to), pi)) {
-    free(pi.name);
-    return -EACCES;
-  }
-
-  free(pi.name);
-
   res = source_rename(from, to);
   if (res == -1)
     return -errno;
@@ -359,22 +313,6 @@ static int xmp_rename(const char *from, const char *to, unsigned int flags) {
 
 static int xmp_link(const char *from, const char *to) {
   int res;
-  struct process_info pi;
-  struct fuse_context *fc = fuse_get_context();
-
-  pi.PID = fc->pid;
-  pi.UID = fc->uid;
-  pi.name = get_process_name_by_pid(pi.PID);
-
-  // fprintf(stderr, "%s, %d\n", path, ask_access(path, pi));
-  if (!interactive_access(real_filename(from), pi)) {
-    free(pi.name);
-    return -EACCES;
-  }
-
-  // no need to check the access to the "to" file, see link(2)
-
-  free(pi.name);
 
   res = source_link(from, to);
   if (res == -1)
@@ -385,20 +323,6 @@ static int xmp_link(const char *from, const char *to) {
 
 static int xmp_chmod(const char *path, mode_t mode, struct fuse_file_info *fi) {
   int res;
-  struct process_info pi;
-  struct fuse_context *fc = fuse_get_context();
-
-  pi.PID = fc->pid;
-  pi.UID = fc->uid;
-  pi.name = get_process_name_by_pid(pi.PID);
-
-  // fprintf(stderr, "%s, %d\n", path, ask_access(path, pi));
-  if (!interactive_access(real_filename(path), pi)) {
-    free(pi.name);
-    return -EACCES;
-  }
-
-  free(pi.name);
 
   if (fi)
     res = fchmod(fi->fh, mode);
@@ -410,27 +334,9 @@ static int xmp_chmod(const char *path, mode_t mode, struct fuse_file_info *fi) {
   return 0;
 }
 
-/**
- * This filesystem is not designed for multiuser operation (e.g. with
- * allow_other) so there is little point in having chown implemnted
- */
 static int xmp_chown(const char *path, uid_t uid, gid_t gid,
                      struct fuse_file_info *fi) {
   int res;
-  struct process_info pi;
-  struct fuse_context *fc = fuse_get_context();
-
-  pi.PID = fc->pid;
-  pi.UID = fc->uid;
-  pi.name = get_process_name_by_pid(pi.PID);
-
-  // fprintf(stderr, "%s, %d\n", path, ask_access(path, pi));
-  if (!interactive_access(real_filename(path), pi)) {
-    free(pi.name);
-    return -EACCES;
-  }
-
-  free(pi.name);
 
   if (fi)
     res = fchown(fi->fh, uid, gid);
@@ -754,7 +660,7 @@ static off_t xmp_lseek(const char *path, off_t off, int whence,
 static const struct fuse_operations xmp_oper = {
     .init = xmp_init,
     .getattr = xmp_getattr,
-    .access = xmp_access,
+    // .access = xmp_access,
     .readlink = xmp_readlink,
     .opendir = xmp_opendir,
     .readdir = xmp_readdir,
@@ -770,7 +676,7 @@ static const struct fuse_operations xmp_oper = {
     .chown = xmp_chown,
     .truncate = xmp_truncate,
 #ifdef HAVE_UTIMENSAT
-//  .utimens = xmp_utimens,
+// .utimens = xmp_utimens,
 #endif
     .create = xmp_create,
     .open = xmp_open,

src/sourcefs.c

@@ -66,11 +66,6 @@ int source_symlink(const char *target, const char *linkpath) {
   return symlinkat(target, handle.root_fd, relative_linkpath);
 }
 
-int source_access(const char *filename, int mode) {
-  const char *relative_filename = source_filename_translate(filename);
-  return faccessat(handle.root_fd, relative_filename, mode, 0);
-}
-
 DIR *source_opendir(const char *filename) {
   const char *relative_filename = source_filename_translate(filename);
   int fd = openat(handle.root_fd, relative_filename, 0);

src/sourcefs.h

@@ -47,8 +47,6 @@ int source_chown(const char *filename, uid_t owner, gid_t group);
 
 int source_truncate(const char *filename, off_t length);
 
-int source_access(const char *filename, int mode);
-
 /* `open` and `create` are designed to correspond to fuse operations, not the
  * libc's `open(2)`. Both of them actually call `openat`. */
 

test/test.bash

@@ -4,7 +4,7 @@
 
 rm -rf ./protected
 mkdir protected
-touch ./protected/do-not-remove ./protected/should-be-removed ./protected/truth ./protected/perm000 ./protected/perm777 ./protected/should-be-renamed ./protected/do-not-rename
+touch ./protected/do-not-remove ./protected/should-be-removed ./protected/truth ./protected/perm000 ./protected/perm777 ./protected/this-name-is-wrong
 chmod 777 ./protected/perm777 ./protected/perm000
 echo "Free code, free world." >./protected/motto
 
@@ -70,11 +70,11 @@ rm ./protected/should-be-removed >/dev/null 2>/dev/null &&
 # rename files
 
 zenity --set-fake-response no
-mv ./protected/do-not-rename ./protected/terrible-name 2>/dev/null &&
+mv ./protected/truth ./protected/lie 2>/dev/null &&
   echo "[ICFS-TEST]: mv can rename protected/truth despite access being denied!" ||
   echo "[ICFS-TEST]: OK" # EACCESS
 zenity --set-fake-response yes_tmp
-mv ./protected/should-be-renamed ./protected/great-name 2>/dev/null &&
+mv ./protected/this-name-is-wrong ./protected/this-name-is-correct 2>/dev/null &&
   echo "[ICFS-TEST]: OK" ||
   echo "[ICFS-TEST]: mv cannot rename should-be-removed to renamed-file despite access being permitted!" # OK