// stat an inode directly // fill in the stat buffer, but do NOT call the user route // always succeeds // NOTE: fent must be read-locked int fskit_entry_fstat( struct fskit_entry* fent, struct stat* sb ) { // fill in defaults sb->st_dev = 0; sb->st_ino = fent->file_id; sb->st_mode = fskit_fullmode( fent->type, fent->mode ); sb->st_nlink = fent->link_count; sb->st_uid = fent->owner; sb->st_gid = fent->group; sb->st_rdev = fent->dev; sb->st_size = fent->size; sb->st_blksize = 0; sb->st_blocks = 0; sb->st_atim.tv_sec = fent->atime_sec; sb->st_atim.tv_nsec = fent->atime_nsec; sb->st_mtim.tv_sec = fent->mtime_sec; sb->st_mtim.tv_nsec = fent->mtime_nsec; sb->st_ctim.tv_sec = fent->ctime_sec; sb->st_ctim.tv_nsec = fent->ctime_nsec; return 0; }
// readdir: equivocate about which devices exist, depending on who's asking // omit entries if the ACLs forbid them int vdevfs_readdir( struct fskit_core* core, struct fskit_match_group* grp, struct fskit_entry* fent, struct fskit_dir_entry** dirents, size_t num_dirents ) { int rc = 0; struct fskit_entry* child = NULL; // entries to omit in the listing vector<int> omitted_idx; pid_t pid = 0; uid_t uid = 0; gid_t gid = 0; struct vdevfs* vdev = (struct vdevfs*)fskit_core_get_user_data( core ); struct fskit_fuse_state* fs_state = fskit_fuse_get_state(); struct stat sb; struct pstat ps; char* child_path = NULL; pid = fskit_fuse_get_pid(); uid = fskit_fuse_get_uid( fs_state ); gid = fskit_fuse_get_gid( fs_state ); vdev_debug("vdevfs_readdir(%s, %zu) from user %d group %d task %d\n", grp->path, num_dirents, uid, gid, pid ); // see who's asking rc = pstat( pid, &ps, 0 ); if( rc != 0 ) { vdev_error("pstat(%d) rc = %d\n", pid, rc ); return -EIO; } for( unsigned int i = 0; i < num_dirents; i++ ) { // skip . and .. if( strcmp(dirents[i]->name, ".") == 0 || strcmp(dirents[i]->name, "..") == 0 ) { continue; } // find the associated fskit_entry child = fskit_dir_find_by_name( fent, dirents[i]->name ); if( child == NULL ) { // strange, shouldn't happen... continue; } fskit_entry_rlock( child ); // construct a stat buffer from what we actually need memset( &sb, 0, sizeof(struct stat) ); sb.st_uid = child->owner; sb.st_gid = child->group; sb.st_mode = fskit_fullmode( child->type, child->mode ); child_path = fskit_fullpath( grp->path, child->name, NULL ); if( child_path == NULL ) { // can't continue; OOM fskit_entry_unlock( child ); rc = -ENOMEM; break; } // filter it rc = vdev_acl_apply_all( vdev->config, vdev->acls, vdev->num_acls, child_path, &ps, uid, gid, &sb ); if( rc < 0 ) { vdev_error("vdev_acl_apply_all('%s', uid=%d, gid=%d, pid=%d) rc = %d\n", child_path, uid, gid, pid, rc ); rc = -EIO; } else if( rc == 0 || (sb.st_mode & 0777) == 0 ) { // omit this one vdev_debug("Filter '%s'\n", child->name ); omitted_idx.push_back( i ); rc = 0; } else { // success; matched rc = 0; } fskit_entry_unlock( child ); free( child_path ); // error? if( rc != 0 ) { break; } } // skip ACL'ed entries for( unsigned int i = 0; i < omitted_idx.size(); i++ ) { fskit_readdir_omit( dirents, omitted_idx[i] ); } return rc; }