有效的 HTTP URI 是符合RFC 2616的 HTTP/1.1 标准。它说:
... For definitive information on
URL syntax and semantics, see "Uniform Resource Identifiers (URI):
Generic Syntax and Semantics," RFC 2396 [42] (which replaces RFCs
1738 [4] and RFC 1808 [11]). This specification adopts the
definitions of "URI-reference", "absoluteURI", "relativeURI", "port",
"host","abs_path", "rel_path", and "authority" from that
specification.
和
The "http" scheme is used to locate network resources via the HTTP
protocol. This section defines the scheme-specific syntax and
semantics for http URLs.
http_URL = "http:" "//" host [ ":" port ] [ abs_path [ "?" query ]]
如果我们深入研究RFC 2396,它定义host
为:
host = hostname | IPv4address
hostname = *( domainlabel "." ) toplabel [ "." ]
domainlabel = alphanum | alphanum *( alphanum | "-" ) alphanum
toplabel = alpha | alpha *( alphanum | "-" ) alphanum
让我们也看看RFC 3986
reg-name 语法允许百分比编码的八位字节,以便以独立于底层名称解析技术的统一方式表示非 ASCII 注册名称。非 ASCII 字符必须首先根据 UTF-8 [STD63] 进行编码,然后必须对相应 UTF-8 序列的每个八位字节进行百分比编码才能表示为 URI 字符。 生成 URI 的应用程序不得在主机中使用百分比编码,除非它用于表示 UTF-8 字符序列。
所以 Firefox 不重定向你是完全正确的。%67oogle.com
是 URL 的无效主机部分。