Audit INI functions and macros, and replace them with better alternatives (#21146)

Audit zend_ini_string(), INI_STR(), and related functions and macros, and all other INI_* macros.

The primary motivation is that these APIs should return a `const char*` because the `char*` is owned by a zend_string, and thus should never be released.

Moreover, the INI_STR() API doesn't follow our usual naming scheme as it returns a char* rather than a zend_string*.

In this PR new zend_ini_{bool|long|double|str|string}_literal() macros are introduced replacing the INI_{BOOL|INT|FLT|STR} macros which follow our more modern naming convention.
Moreover, the INI_BOOL() macro didn't produce correct values if the INI string is a word like "true" or "on".

The INI_ORIG_* APIs are removed because a Sourcegraph search shows 0 results, other than the one case used in ext/tidy that we fix using the typical API.

Add some additional checks for the value of an INI string to ensure it doesn't contain a nul byte when describing a path.

Author: Girgias

UPGRADING.INTERNALS

@@ -75,6 +75,14 @@ PHP 8.6 INTERNALS UPGRADE NOTES
   . Added a C23_ENUM() helper macro to define forward-compatible fixed-size
     enums.
   . Extended php_stream_filter_ops with seek method.
+  . The INI_STR(), INI_INT(), INI_FLT(), and INI_BOOL() macros have been
+    removed. Instead new zend_ini_{bool|long|double|str|string}_literal()
+    macros have been added. This fixes an internal naming inconsistency as
+    "str" usually means zend_string*, and "string" means char*.
+    However INI_STR() returned a char*
+  . The INI_ORIG_{INT|STR|FLT|BOOL}() macros have been removed as they are
+    unused. If this behaviour is required fall back to the zend_ini_*
+    functions.
 
 ========================
 2. Build system changes

Zend/zend_fibers.c

@@ -572,9 +572,9 @@ static ZEND_STACK_ALIGNED void zend_fiber_execute(zend_fiber_transfer *transfer)
 	zend_fiber *fiber = EG(active_fiber);
 
 	/* Determine the current error_reporting ini setting. */
-	zend_long error_reporting = INI_INT("error_reporting");
-	/* If error_reporting is 0 and not explicitly set to 0, INI_STR returns a null pointer. */
-	if (!error_reporting && !INI_STR("error_reporting")) {
+	zend_long error_reporting = zend_ini_long_literal("error_reporting");
+	/* If error_reporting is 0 and not explicitly set to 0, zend_ini_str returns a null pointer. */
+	if (!error_reporting && !zend_ini_str_literal("error_reporting")) {
 		error_reporting = E_ALL;
 	}
 

Zend/zend_highlight.c

@@ -79,8 +79,8 @@ ZEND_API void zend_highlight(zend_syntax_highlighter_ini *syntax_highlighter_ini
 {
 	zval token;
 	int token_type;
-	char *last_color = syntax_highlighter_ini->highlight_html;
-	char *next_color;
+	const char *last_color = syntax_highlighter_ini->highlight_html;
+	const char *next_color;
 
 	zend_printf("<pre><code style=\"color: %s\">", last_color);
 	/* highlight stuff coming back from zendlex() */

Zend/zend_highlight.h

@@ -30,11 +30,11 @@
 
 
 typedef struct _zend_syntax_highlighter_ini {
-	char *highlight_html;
-	char *highlight_comment;
-	char *highlight_default;
-	char *highlight_string;
-	char *highlight_keyword;
+	const char *highlight_html;
+	const char *highlight_comment;
+	const char *highlight_default;
+	const char *highlight_string;
+	const char *highlight_keyword;
 } zend_syntax_highlighter_ini;
 
 

Zend/zend_ini.c

@@ -491,15 +491,15 @@ ZEND_API double zend_ini_double(const char *name, size_t name_length, bool orig)
 }
 /* }}} */
 
-ZEND_API char *zend_ini_string_ex(const char *name, size_t name_length, bool orig, bool *exists) /* {{{ */
+ZEND_API const char *zend_ini_string_ex(const char *name, size_t name_length, bool orig, bool *exists) /* {{{ */
 {
 	zend_string *str = zend_ini_str_ex(name, name_length, orig, exists);
 
 	return str ? ZSTR_VAL(str) : NULL;
 }
 /* }}} */
 
-ZEND_API char *zend_ini_string(const char *name, size_t name_length, bool orig) /* {{{ */
+ZEND_API const char *zend_ini_string(const char *name, size_t name_length, bool orig) /* {{{ */
 {
 	zend_string *str = zend_ini_str(name, name_length, orig);
 

Zend/zend_ini.h

@@ -88,13 +88,19 @@ ZEND_API void display_ini_entries(zend_module_entry *module);
 
 ZEND_API zend_long zend_ini_long(const char *name, size_t name_length, bool orig);
 ZEND_API double zend_ini_double(const char *name, size_t name_length, bool orig);
-ZEND_API char *zend_ini_string(const char *name, size_t name_length, bool orig);
-ZEND_API char *zend_ini_string_ex(const char *name, size_t name_length, bool orig, bool *exists);
+ZEND_API const char *zend_ini_string(const char *name, size_t name_length, bool orig);
+ZEND_API const char *zend_ini_string_ex(const char *name, size_t name_length, bool orig, bool *exists);
 ZEND_API zend_string *zend_ini_str(const char *name, size_t name_length, bool orig);
 ZEND_API zend_string *zend_ini_str_ex(const char *name, size_t name_length, bool orig, bool *exists);
 ZEND_API zend_string *zend_ini_get_value(zend_string *name);
 ZEND_API bool zend_ini_parse_bool(const zend_string *str);
 
+#define zend_ini_bool_literal(name) zend_ini_parse_bool(zend_ini_str((name), sizeof("" name) - 1, false))
+#define zend_ini_long_literal(name) zend_ini_long((name), sizeof("" name) - 1, false)
+#define zend_ini_double_literal(name) zend_ini_double((name), sizeof("" name) - 1, false)
+#define zend_ini_str_literal(name) zend_ini_str((name), sizeof("" name) - 1, false)
+#define zend_ini_string_literal(name) zend_ini_string((name), sizeof("" name) - 1, false)
+
 /**
  * Parses an ini quantity
  *
@@ -191,16 +197,6 @@ END_EXTERN_C()
 	ZEND_INI_ENTRY3_EX(name, default_value, modifiable, on_modify, (void *) XtOffsetOf(struct_type, property_name), (void *) &struct_ptr, NULL, zend_ini_boolean_displayer_cb)
 #endif
 
-#define INI_INT(name) zend_ini_long((name), strlen(name), 0)
-#define INI_FLT(name) zend_ini_double((name), strlen(name), 0)
-#define INI_STR(name) zend_ini_string_ex((name), strlen(name), 0, NULL)
-#define INI_BOOL(name) ((bool) INI_INT(name))
-
-#define INI_ORIG_INT(name)	zend_ini_long((name), strlen(name), 1)
-#define INI_ORIG_FLT(name)	zend_ini_double((name), strlen(name), 1)
-#define INI_ORIG_STR(name)	zend_ini_string((name), strlen(name), 1)
-#define INI_ORIG_BOOL(name) ((bool) INI_ORIG_INT(name))
-
 #define REGISTER_INI_ENTRIES() zend_register_ini_entries_ex(ini_entries, module_number, type)
 #define UNREGISTER_INI_ENTRIES() zend_unregister_ini_entries_ex(module_number, type)
 #define DISPLAY_INI_ENTRIES() display_ini_entries(zend_module)

Zend/zend_multibyte.c

@@ -114,8 +114,8 @@ ZEND_API zend_result zend_multibyte_set_functions(const zend_multibyte_functions
 	 * populated, we need to reinitialize script_encoding here.
 	 */
 	{
-		const char *value = zend_ini_string("zend.script_encoding", sizeof("zend.script_encoding") - 1, 0);
-		zend_multibyte_set_script_encoding_by_string(value, strlen(value));
+		const zend_string *value = zend_ini_str_literal("zend.script_encoding");
+		zend_multibyte_set_script_encoding_by_string(ZSTR_VAL(value), ZSTR_LEN(value));
 	}
 	return SUCCESS;
 }

ext/com_dotnet/com_dotnet.c

@@ -127,7 +127,6 @@ static HRESULT dotnet_bind_runtime(LPVOID FAR *ppv)
 	typedef HRESULT (STDAPICALLTYPE *cbtr_t)(LPCWSTR pwszVersion, LPCWSTR pwszBuildFlavor, REFCLSID rclsid, REFIID riid, LPVOID FAR *ppv);
 	cbtr_t CorBindToRuntime;
 	OLECHAR *oleversion;
-	char *version;
 
 	mscoree = LoadLibraryA("mscoree.dll");
 	if (mscoree == NULL) {
@@ -140,11 +139,11 @@ static HRESULT dotnet_bind_runtime(LPVOID FAR *ppv)
 		return S_FALSE;
 	}
 
-	version = INI_STR("com.dotnet_version");
-	if (version == NULL || *version == '\0') {
+	const zend_string *version = zend_ini_str_literal("com.dotnet_version");
+	if (version == NULL || ZSTR_LEN(version) == 0) {
 		oleversion = NULL;
 	} else {
-		oleversion = php_com_string_to_olestring(version, strlen(version), COMG(code_page));
+		oleversion = php_com_string_to_olestring(ZSTR_VAL(version), ZSTR_LEN(version), COMG(code_page));
 	}
 
 	hr = CorBindToRuntime(oleversion, NULL, &CLSID_CorRuntimeHost, &IID_ICorRuntimeHost, ppv);

ext/curl/interface.c

@@ -1100,8 +1100,6 @@ static void create_certinfo(struct curl_certinfo *ci, zval *listcode)
    Set default options for a handle */
 static void _php_curl_set_default_options(php_curl *ch)
 {
-	char *cainfo;
-
 	curl_easy_setopt(ch->cp, CURLOPT_NOPROGRESS,        1L);
 	curl_easy_setopt(ch->cp, CURLOPT_VERBOSE,           0L);
 	curl_easy_setopt(ch->cp, CURLOPT_ERRORBUFFER,       ch->err.str);
@@ -1114,9 +1112,9 @@ static void _php_curl_set_default_options(php_curl *ch)
 	curl_easy_setopt(ch->cp, CURLOPT_DNS_CACHE_TIMEOUT, 120L);
 	curl_easy_setopt(ch->cp, CURLOPT_MAXREDIRS, 20L); /* prevent infinite redirects */
 
-	cainfo = INI_STR("openssl.cafile");
+	const char *cainfo = zend_ini_string_literal("openssl.cafile");
 	if (!(cainfo && cainfo[0] != '\0')) {
-		cainfo = INI_STR("curl.cainfo");
+		cainfo = zend_ini_string_literal("curl.cainfo");
 	}
 	if (cainfo && cainfo[0] != '\0') {
 		curl_easy_setopt(ch->cp, CURLOPT_CAINFO, cainfo);

ext/date/php_date.c

@@ -5478,18 +5478,18 @@ static void php_do_date_sunrise_sunset(INTERNAL_FUNCTION_PARAMETERS, bool calc_s
 	ZEND_PARSE_PARAMETERS_END();
 
 	if (latitude_is_null) {
-		latitude = INI_FLT("date.default_latitude");
+		latitude = zend_ini_double_literal("date.default_latitude");
 	}
 
 	if (longitude_is_null) {
-		longitude = INI_FLT("date.default_longitude");
+		longitude = zend_ini_double_literal("date.default_longitude");
 	}
 
 	if (zenith_is_null) {
 		if (calc_sunset) {
-			zenith = INI_FLT("date.sunset_zenith");
+			zenith = zend_ini_double_literal("date.sunset_zenith");
 		} else {
-			zenith = INI_FLT("date.sunrise_zenith");
+			zenith = zend_ini_double_literal("date.sunrise_zenith");
 		}
 	}