Edit File: secureio.h
// Secure I/O and filesystem operations #ifndef _SECUREIO_H_ #define _SECUREIO_H_ #include <sys/types.h> #define SECUREIO_BUFSIZE 8192 // Writes absolute path pointed by descriptor fd to buffer *buf // Returns buf if successful // Returns NULL if error has occured char *get_path_from_descriptor(int fd, char *buf); // Returns 1 if subdir is subdirectory of dir, 0 otherwise int is_subdir(const char *dir, const char *subdir); // Opens path for reading not following symlinks and verifies that opened path is inside parent_path // Returns: // descriptor if successful // -1 if path does not exist or is a symlink // -2 if opened path is NOT inside parent_path or cannot be determined int open_not_symlink(const char *path, const char *parent_path); // Closes descriptor (if it is > 0) void closefd(int fd); // Tries to read first directory entry in order to ensure that descriptor is valid // Returns 0 if reading succeeded or -1 if error has occured int check_dir(int fd); // Checks if path is a directory (in secure manner) // Also opens path (if descriptor fd == -1) and then checks that opened path is inside parent_path // Returns descriptor if path refers to directory // Returns -1 if path does not exist or is not a directory // Returns -2 if opened path is NOT inside parent_path or cannot be determined int isdir(const char *path, int fd, const char *parent_path); // Sets permissions to directory (in secure manner) // Returns descriptor if successful // Returns -1 if error has occured // Returns -2 if opened path is NOT inside parent_path or cannot be determined int set_perm_dir_secure(const char *path, mode_t perm, int fd, const char *parent_path); // Sets owner and group of directory (in secure manner) // Returns descriptor if successful // Returns -1 if error has occured // Returns -2 if opened path is NOT inside parent_path or cannot be determined int set_owner_dir_secure(const char *path, uid_t uid, gid_t gid, int fd, const char *parent_path); // Creates directory if it does not exist, sets permissions/owner otherwise // Returns descriptor if successful // Returns -1 if error has occured int create_dir_secure(const char *path, mode_t perm, uid_t uid, gid_t gid, int fd, const char *parent_path); // Recursive directory creation function // Returns 0 if successful // Returns -1 if error has occured int makedirs_secure(const char *path, mode_t perm, uid_t uid, gid_t gid, const char *parent_path); #endif