-/**
- * @brief Determine if the given file descriptor might refer to an
- * (unsafe) hard link.
- *
- * @param fd
- * The file descriptor whose link count we want to investigate.
- *
- * @return true if we are certain that @c fd does not describe a hard
- * link, and false otherwise. In case of error, false is returned,
- * because we are not sure that @c fd is not a hard link.
- */
-bool is_hardlink_safe(int fd) {
- if (fd <= 0) {
- return false;
- }
- struct stat s;
- if (fstat(fd, &s) == 0) {
- return (s.st_nlink == 1 || S_ISDIR(s.st_mode));
- }
- else {
- return false;
- }
-}
-
-
-/**
- * @brief Determine whether or not the given file descriptor is for
- * a regular file.
- *
- * @param fd
- * The file descriptor to test for regular-fileness.
- *
- * @return true if @c fd describes a regular file, and false otherwise.
- */
-bool is_regular_file(int fd) {
- if (fd <= 0) {
- return false;
- }
-
- struct stat s;
- if (fstat(fd, &s) == 0) {
- return S_ISREG(s.st_mode);
- }
- else {
- return false;
- }
-}
-
-
-
/**
* @brief Determine whether or not the given path is accessible.
*
}
-/**
- * @brief Determine whether or not the given file descriptor is for
- * a directory.
- *
- * @param fd
- * The file descriptor whose directoryness is in question.
- *
- * @return true if @c fd describes a directory, and false otherwise.
- */
-bool is_directory(int fd) {
- if (fd <= 0) {
- return false;
- }
-
- struct stat s;
- if (fstat(fd, &s) == 0) {
- return S_ISDIR(s.st_mode);
- }
- else {
- return false;
- }
-}
-
/**
* returned. Otherwise, @c ACL_SUCCESS.
*
*/
-int acl_set_entry(acl_t* aclp,
- acl_entry_t entry) {
+int acl_set_entry(acl_t* aclp, acl_entry_t entry) {
acl_tag_t entry_tag;
if (acl_get_tag_type(entry, &entry_tag) == ACL_ERROR) {
/**
- * @brief Determine whether @c fd is executable (by anyone) or a
- * directory.
+ * @brief Determine whether @c fd is executable by anyone.
+ *
*
* This is used as part of the heuristic to determine whether or not
* we should mask the execute bit when inheriting an ACL. If @c fd
- * describes a directory, the answer is a clear-cut yes. This behavior
- * is modeled after the capital 'X' perms of setfacl.
- *
- * If @c fd describes a file, we check the @a effective permissions,
- * contrary to what setfacl does.
+ * describes a file, we check the @a effective permissions, contrary
+ * to what setfacl does.
*
* @param fd
* The file descriptor to check.
*
* @return
- * - @c ACL_SUCCESS - @c fd describes a directory, or someone has effective
- execute permissions.
- * - @c ACL_FAILURE - @c fd describes a regular file and nobody can execute
- it.
+ * - @c ACL_SUCCESS - Someone has effective execute permissions on @c fd.
+ * - @c ACL_FAILURE - Nobody can execute @c fd.
* - @c ACL_ERROR - Unexpected library error.
*/
-int any_can_execute_or_dir(int fd) {
-
- if (is_directory(fd)) {
- /* That was easy... */
- return ACL_SUCCESS;
- }
-
+int any_can_execute(int fd) {
acl_t acl = acl_get_fd(fd);
if (acl == (acl_t)NULL) {
- perror("any_can_execute_or_dir (acl_get_file)");
+ perror("any_can_execute (acl_get_file)");
return ACL_ERROR;
}
if (acl_is_minimal(acl)) {
struct stat s;
if (fstat(fd, &s) == -1) {
- perror("any_can_execute_or_dir (fstat)");
+ perror("any_can_execute (fstat)");
result = ACL_ERROR;
goto cleanup;
}
acl_tag_t tag = ACL_UNDEFINED_TAG;
if (acl_get_tag_type(entry, &tag) == ACL_ERROR) {
- perror("any_can_execute_or_dir (acl_get_tag_type)");
+ perror("any_can_execute_or (acl_get_tag_type)");
result = ACL_ERROR;
goto cleanup;
}
acl_permset_t permset;
if (acl_get_permset(entry, &permset) == ACL_ERROR) {
- perror("any_can_execute_or_dir (acl_get_permset)");
+ perror("any_can_execute_or (acl_get_permset)");
result = ACL_ERROR;
goto cleanup;
}
int gp_result = acl_get_perm(permset, ACL_EXECUTE);
if (gp_result == ACL_ERROR) {
- perror("any_can_execute_or_dir (acl_get_perm)");
+ perror("any_can_execute (acl_get_perm)");
result = ACL_ERROR;
goto cleanup;
}
}
if (ge_result == ACL_ERROR) {
- perror("any_can_execute_or_dir (acl_get_entry)");
+ perror("any_can_execute (acl_get_entry)");
result = ACL_ERROR;
goto cleanup;
}
int assign_default_acl(const char* path, acl_t acl) {
if (path == NULL) {
- errno = ENOENT;
+ errno = EINVAL;
+ perror("assign_default_acl (args)");
return ACL_ERROR;
}
* @param path
* The path whose ACL we would like to reset to its default.
*
+ * @param sp
+ * A pointer to a stat structure for @c path, or @c NULL if you don't
+ * have one handy.
+ *
* @param no_exec_mask
* The value (either true or false) of the --no-exec-mask flag.
*
* or the parent of @c path is not a directory.
* - @c ACL_ERROR - Unexpected library error.
*/
-int apply_default_acl(const char* path, bool no_exec_mask) {
+int apply_default_acl(const char* path,
+ const struct stat* sp,
+ bool no_exec_mask) {
if (path == NULL) {
- errno = ENOENT;
+ errno = EINVAL;
+ perror("apply_default_acl (args)");
return ACL_ERROR;
}
* race condition here, but the window is as small as possible
* between when we open the file descriptor (look above) and when we
* fstat it.
+ *
+ * Note: we only need to call fstat ourselves if we weren't passed a
+ * valid pointer to a stat structure (nftw does that).
*/
- if (!is_hardlink_safe(fd)) {
- result = ACL_FAILURE;
- goto cleanup;
+ if (sp == NULL) {
+ struct stat s;
+ if (fstat(fd, &s) == -1) {
+ perror("apply_default_acl (fstat)");
+ goto cleanup;
+ }
+
+ sp = &s;
}
- if (!is_regular_file(fd) && !is_directory(fd)) {
- result = ACL_FAILURE;
- goto cleanup;
+ if (!S_ISDIR(sp->st_mode)) {
+ /* If it's not a directory, make sure it's a regular,
+ non-hard-linked file. */
+ if (!S_ISREG(sp->st_mode) || sp->st_nlink != 1) {
+ result = ACL_FAILURE;
+ goto cleanup;
+ }
}
+
/* Default to not masking the exec bit; i.e. applying the default
ACL literally. If --no-exec-mask was not specified, then we try
- to "guess" whether or not to mask the exec bit. */
+ to "guess" whether or not to mask the exec bit. This behavior
+ is modeled after the capital 'X' perms of setfacl. */
bool allow_exec = true;
if (!no_exec_mask) {
- int ace_result = any_can_execute_or_dir(fd);
+ /* Never mask the execute bit on directories. */
+ int ace_result = any_can_execute(fd) || S_ISDIR(sp->st_mode);
if (ace_result == ACL_ERROR) {
- perror("apply_default_acl (any_can_execute_or_dir)");
+ perror("apply_default_acl (any_can_execute)");
result = ACL_ERROR;
goto cleanup;
}
*
*/
int apply_default_acl_nftw(const char *target,
- const struct stat *s,
+ const struct stat *sp,
int info,
struct FTW *ftw) {
- if (apply_default_acl(target, false)) {
+ if (apply_default_acl(target, sp, false)) {
return FTW_CONTINUE;
}
else {
*
*/
int apply_default_acl_nftw_x(const char *target,
- const struct stat *s,
+ const struct stat *sp,
int info,
struct FTW *ftw) {
- if (apply_default_acl(target, true)) {
+ if (apply_default_acl(target, sp, true)) {
return FTW_CONTINUE;
}
else {
bool apply_default_acl_recursive(const char *target, bool no_exec_mask) {
if (!is_path_directory(target)) {
- return apply_default_acl(target, no_exec_mask);
+ return apply_default_acl(target, NULL, no_exec_mask);
}
int max_levels = 256;
}
else {
/* It's either a normal file, or we're not operating recursively. */
- reapp_result = apply_default_acl(target, no_exec_mask);
+ reapp_result = apply_default_acl(target, NULL, no_exec_mask);
}
if (!reapp_result) {
projects / apply-default-acl.git / blobdiff