wiley http essentials protocols for secure scaleable web sites phần 6

vi để xác định phần nào của tài nguyên có mặt trong thông điệp của phản ứng. Redirection (3xx) mã trạng thái 300-399 nói với khách hàng mà nó cần phải có hành động hơn nữa để đáp ứng yêu cầu của nó. Cụ thể, máy chủ yêu cầu khách hàng để cấp lại yêu cầu của nó, nhưng đối với một uri khác nhau. | Securing HTTP 155 Table continued Step Action 5 Construct a character string by combining the result from step 2 the nonce supplied by the server the nc value the cnonce value the qop value and the result from step 4 all separated by colons . 6 Calculate the MD5 digest for the character string obtained in step 5 and represent the result as 32 ASCII characters. This value is the digest. The client includes this new digest value in its reissued request along with an appropriate qop value. The qop parameter indicates that it has accepted the server s proposal to include integrity protection. GET secret HTTP Authorization Digest username pooh realm users@ qop auth-int nonce dcd98bc09f81043d3a8cb935ae393db90674 nc 00000001 cnonce 32cfe192fd109232aa1b8fe09d18d5efe53 uri secret response dcd98bc09f81043d3a8cb935ae393db90674 When the client accepts a proposal to use integrity protection the server should do likewise. In the digest for its response therefore it includes the entity body of that response in its own digest calculation. It confirms integrity protection with the qop value of auth-int. HTTP 200 OK Authentication-Info qop auth-int rspauth 78d98bc09f81ba3d3a8cb935a9993db90674 cnonce 32cfe192fd109232aa1b8fe09d18d5efe53 nc 00000001 156 HTTP Essentials Table details the digest calculation. The difference is in step 3 where the server calculates a2. Note that this table does not include frequent client protection calculations. Table Server Digest Calculation for Integrity Protection Step Action 1 Construct a character string consisting of the username realm and password each item separated by a colon pooh users@ honey for example. This is string A1. 2 Calculate the MD5 digest for this character string and represent the result in hexadecimal as 32 ASCII characters. 3 Construct a second character string consisting of a colon followed by the URI of the client s request followed by .