added mb_check_encoding( ). detect possible invalid encoding attack(avoids a security issue).

3 files changed, 65 insertions, 0 deletions

diff --git a/ext/mbstring/libmbfl/mbfl/mbfilter.c b/ext/mbstring/libmbfl/mbfl/mbfilter.c
index 9f16331874..a8e3b68d33 100644
--- a/ext/mbstring/libmbfl/mbfl/mbfilter.c
+++ b/ext/mbstring/libmbfl/mbfl/mbfilter.c
@@ -335,6 +335,10 @@ int mbfl_buffer_illegalchars(mbfl_buffer_converter *convd)
 {
 	int num_illegalchars = 0;
 
+	if (convd == NULL) {
+		return 0;
+	}
+
 	if (convd->filter1 != NULL) {
 		num_illegalchars += convd->filter1->num_illegalchar;
 	}
diff --git a/ext/mbstring/mbstring.c b/ext/mbstring/mbstring.c
index f02ce1c76e..48f2496a71 100644
--- a/ext/mbstring/mbstring.c
+++ b/ext/mbstring/mbstring.c
@@ -253,6 +253,7 @@ function_entry mbstring_functions[] = {
 	PHP_FE(mb_decode_numericentity,		NULL)
 	PHP_FE(mb_send_mail,					NULL)
 	PHP_FE(mb_get_info,					NULL)
+	PHP_FE(mb_check_encoding,		NULL)
 	PHP_FALIAS(mbstrlen,	mb_strlen,	NULL)
 	PHP_FALIAS(mbstrpos,	mb_strpos,	NULL)
 	PHP_FALIAS(mbstrrpos,	mb_strrpos,	NULL)
@@ -3812,6 +3813,65 @@ PHP_FUNCTION(mb_get_info)
 }
 /* }}} */
 
+/* {{{ proto bool mb_check_encoding([string var[, string encoding]])
+   Check if the string is valid for the specified encoding */
+PHP_FUNCTION(mb_check_encoding)
+{
+	char *var = NULL;
+	int var_len;
+	char *enc = NULL;
+	int enc_len;
+	mbfl_buffer_converter *convd;
+	enum mbfl_no_encoding no_encoding = MBSTRG(current_internal_encoding);
+	mbfl_string string, result, *ret = NULL;
+	long illegalchars = 0;
+
+	if (zend_parse_parameters(ZEND_NUM_ARGS() TSRMLS_CC, "|ss", &var, &var_len, &enc, &enc_len) == FAILURE) {
+		RETURN_FALSE;
+	}
+
+	if (var == NULL) {
+		RETURN_BOOL(MBSTRG(illegalchars) == 0);
+	}
+
+	if (enc != NULL) {
+		no_encoding = mbfl_name2no_encoding(enc);
+		if (no_encoding == mbfl_no_encoding_invalid || no_encoding == mbfl_no_encoding_pass) {
+			php_error_docref(NULL TSRMLS_CC, E_WARNING, "Invalid encoding \"%s\"", enc);
+			RETURN_FALSE;
+		}
+	}
+	
+	convd = mbfl_buffer_converter_new(no_encoding, no_encoding, 0);
+	if (convd == NULL) {
+		php_error_docref(NULL TSRMLS_CC, E_WARNING, "Unable to create converter");
+		RETURN_FALSE;
+	}	
+	mbfl_buffer_converter_illegal_mode(convd, MBSTRG(current_filter_illegal_mode));
+	mbfl_buffer_converter_illegal_substchar(convd, MBSTRG(current_filter_illegal_substchar));	
+	
+	/* initialize string */
+	mbfl_string_init(&string);
+	mbfl_string_init(&result);
+	string.no_encoding = no_encoding;
+	string.no_language = MBSTRG(current_language);
+
+	string.val = (unsigned char *)var;
+	string.len = var_len;
+	ret = mbfl_buffer_converter_feed_result(convd, &string, &result);
+	illegalchars = mbfl_buffer_illegalchars(convd);
+	mbfl_buffer_converter_delete(convd);
+
+	if (ret != NULL) {
+		MBSTRG(illegalchars) += illegalchars;
+		efree(ret->val);
+		RETURN_BOOL(illegalchars == 0);
+	} else {
+		RETURN_FALSE;
+	}
+}
+/* }}} */
+
 /* {{{ MBSTRING_API int php_mb_encoding_translation() */
 MBSTRING_API int php_mb_encoding_translation(TSRMLS_D) 
 {
diff --git a/ext/mbstring/mbstring.h b/ext/mbstring/mbstring.h
index 95e2616077..c64a296aab 100644
--- a/ext/mbstring/mbstring.h
+++ b/ext/mbstring/mbstring.h
@@ -117,6 +117,7 @@ PHP_FUNCTION(mb_encode_numericentity);
 PHP_FUNCTION(mb_decode_numericentity);
 PHP_FUNCTION(mb_send_mail);
 PHP_FUNCTION(mb_get_info);
+PHP_FUNCTION(mb_check_encoding);
 
 MBSTRING_API int php_mb_encoding_translation(TSRMLS_D);