fix: narrow the validation of cookies to match RFC6265 (#167)

Author: bewinsnw

index.js

@@ -23,14 +23,60 @@ exports.serialize = serialize;
 var __toString = Object.prototype.toString
 
 /**
- * RegExp to match field-content in RFC 7230 sec 3.2
+ * RegExp to match cookie-name in RFC 6265 sec 4.1.1
+ * This refers out to the obsoleted definition of token in RFC 2616 sec 2.2
+ * which has been replaced by the token definition in RFC 7230 appendix B.
  *
- * field-content = field-vchar [ 1*( SP / HTAB ) field-vchar ]
- * field-vchar   = VCHAR / obs-text
- * obs-text      = %x80-FF
+ * cookie-name       = token
+ * token             = 1*tchar
+ * tchar             = "!" / "#" / "$" / "%" / "&" / "'" /
+ *                     "*" / "+" / "-" / "." / "^" / "_" /
+ *                     "`" / "|" / "~" / DIGIT / ALPHA
  */
 
-var fieldContentRegExp = /^[\u0009\u0020-\u007e\u0080-\u00ff]+$/;
+var cookieNameRegExp = /^[!#$%&'*+\-.^_`|~0-9A-Za-z]+$/;
+
+/**
+ * RegExp to match cookie-value in RFC 6265 sec 4.1.1
+ *
+ * cookie-value      = *cookie-octet / ( DQUOTE *cookie-octet DQUOTE )
+ * cookie-octet      = %x21 / %x23-2B / %x2D-3A / %x3C-5B / %x5D-7E
+ *                     ; US-ASCII characters excluding CTLs,
+ *                     ; whitespace DQUOTE, comma, semicolon,
+ *                     ; and backslash
+ */
+
+var cookieValueRegExp = /^("?)[\u0021\u0023-\u002B\u002D-\u003A\u003C-\u005B\u005D-\u007E]*\1$/;
+
+/**
+ * RegExp to match domain-value in RFC 6265 sec 4.1.1
+ *
+ * domain-value      = <subdomain>
+ *                     ; defined in [RFC1034], Section 3.5, as
+ *                     ; enhanced by [RFC1123], Section 2.1
+ * <subdomain>       = <label> | <subdomain> "." <label>
+ * <label>           = <let-dig> [ [ <ldh-str> ] <let-dig> ]
+ *                     Labels must be 63 characters or less.
+ *                     'let-dig' not 'letter' in the first char, per RFC1123
+ * <ldh-str>         = <let-dig-hyp> | <let-dig-hyp> <ldh-str>
+ * <let-dig-hyp>     = <let-dig> | "-"
+ * <let-dig>         = <letter> | <digit>
+ * <letter>          = any one of the 52 alphabetic characters A through Z in
+ *                     upper case and a through z in lower case
+ * <digit>           = any one of the ten digits 0 through 9
+ */
+
+var domainValueRegExp = /^([a-z0-9]([a-z0-9-]{0,61}[a-z0-9])?)([.][a-z0-9]([a-z0-9-]{0,61}[a-z0-9])?)*$/i;
+
+/**
+ * RegExp to match path-value in RFC 6265 sec 4.1.1
+ *
+ * path-value        = <any CHAR except CTLs or ";">
+ * CHAR              = %x01-7F
+ *                     ; defined in RFC 5234 appendix B.1
+ */
+
+var pathValueRegExp = /^[\u0020-\u003A\u003D-\u007E]*$/;
 
 /**
  * Parse a cookie header.
@@ -116,13 +162,13 @@ function serialize(name, val, options) {
     throw new TypeError('option encode is invalid');
   }
 
-  if (!fieldContentRegExp.test(name)) {
+  if (!cookieNameRegExp.test(name)) {
     throw new TypeError('argument name is invalid');
   }
 
   var value = enc(val);
 
-  if (value && !fieldContentRegExp.test(value)) {
+  if (value && !cookieValueRegExp.test(value)) {
     throw new TypeError('argument val is invalid');
   }
 
@@ -139,15 +185,15 @@ function serialize(name, val, options) {
   }
 
   if (opt.domain) {
-    if (!fieldContentRegExp.test(opt.domain)) {
+    if (!domainValueRegExp.test(opt.domain)) {
       throw new TypeError('option domain is invalid');
     }
 
     str += '; Domain=' + opt.domain;
   }
 
   if (opt.path) {
-    if (!fieldContentRegExp.test(opt.path)) {
+    if (!pathValueRegExp.test(opt.path)) {
       throw new TypeError('option path is invalid');
     }
 

test/serialize.js

@@ -20,6 +20,7 @@ describe('cookie.serialize(name, value)', function () {
   it('should throw for invalid name', function () {
     assert.throws(cookie.serialize.bind(cookie, 'foo\n', 'bar'), /argument name is invalid/)
     assert.throws(cookie.serialize.bind(cookie, 'foo\u280a', 'bar'), /argument name is invalid/)
+    assert.throws(cookie.serialize.bind(cookie, 'foo bar', 'bar'), /argument name is invalid/)
   })
 })
 
@@ -52,6 +53,9 @@ describe('cookie.serialize(name, value, options)', function () {
       assert.throws(cookie.serialize.bind(cookie, 'foo', '+ \n', {
         encode: function (v) { return v }
       }), /argument val is invalid/)
+      assert.throws(cookie.serialize.bind(cookie, 'foo', 'foo bar', {
+        encode: function (v) { return v }
+      }), /argument val is invalid/)
     })
   })