rfc5839.An Extension to Session Initiation Protocol (SIP) Events for Conditional Event Notification

iisapi 原理iisapi介绍在Web开发中，为了实现对IIS服务器的扩展和自定义功能，可以使用iisapi (Internet Information Services Application Programming Interface)。

iisapi是一种基于COM的接口，可用于开发IIS网络服务器的第三方插件和扩展。

架构iisapi的架构主要由以下几个组件组成：•****：这是iisapi的核心组件，包含了与IIS服务器通信和处理请求的功能。

•ISAPI过滤器：过滤器是iisapi的一个重要组件，它可以实现对HTTP请求和响应进行拦截和过滤。

通过注册一个ISAPI过滤器，可以在请求到达IIS之前或响应返回客户端之前对请求和响应进行加工和处理。

•ISAPI扩展：扩展是一种特殊的ISAPI过滤器，它能够直接处理除HTTP请求和响应以外的其他类型的请求，比如FTP、SMTP等。

扩展可以以动态链接库(DLL)的形式提供，通过注册一个网络服务扩展来将其绑定到特定的网站或虚拟目录上。

工作原理iisapi的工作原理可以简要概括为以下几个步骤：1.客户端发送HTTP请求到IIS服务器。

2.IIS服务器接收到请求后，将请求传递给已注册的ISAPI过滤器。

3.ISAPI过滤器根据自定义的逻辑对请求进行过滤、加工或拦截。

4.处理完毕后，ISAPI过滤器将请求传递给IIS进行处理，或者直接返回响应给客户端。

5.如果请求需要使用ISAPI扩展处理，则IIS将请求传递给对应的扩展处理。

6.扩展根据自定义逻辑处理请求，并生成相应的响应数据。

7.IIS将生成的响应数据返回给客户端。

开发步骤使用iisapi进行开发一般包括以下几个步骤：1.创建ISAPI过滤器或扩展的项目：在开发环境中创建一个新的iisapi项目，需要选择对应的语言和开发工具。

2.编写自定义的处理逻辑：根据需求，编写自定义的处理逻辑，可以包括请求拦截、过滤、加工等操作。

1)100 Trying说明caller正在呼叫，但还没联系上callee。

180 Ringing 说明callee已经被联系上,callee的铃正在响.收到这个信息后，等待200 OK2)181 Call is being forwarded说明call被重新路由到另外一个目的地3)182 Queued说明callee当前是不可获得的，但是对方不想直接拒绝呼叫，而是选择放在呼叫队列中4)183 Session progress用来警告caller频段(inband)错误。

当从PSTN收到一个ISDN消息，SIP gateway 产生183 Session progress 。

建立专有承载QCI12xx successful Responses200 OK3xx Redirection Responses5)300 Multiple choices说明呼叫的地址被解析成多个地址，所有的地址都被提供出来，用户或用户代理可以从中选择联系哪个。

6)301 Moved permanently说明指定地址的用户已经永远不可用，在头中已经用另外一个地址替换了.7)302 Moved temporarily说明指定地址的用户临时不可用，在头中已经用另外一个地址代替了.8)305 Use proxy说明caller必须用一个proxy来联系callee.9)380 Alternative service说明call不成功，但是可选择其他的服务4xx Request Failure Responses10)400 Bad Request说明由于非法格式，请求不能被理解。

11)401 Unauthorized说明请求需要用户认证。

12)402 Payment required说明完成会话需要付费.13)403 Forbidden说明server已经收到并能理解请求但不提供服务。

14)404 Not Found说明server有明确的信息在指定的域中用户不存在.15)405 Method Not Allowed说明请求中指定的方法是不被允许的。

IIS短⽂件名漏洞复现图⽂详解⼀、漏洞描述此漏洞实际是由HTTP请求中旧DOS 8.3名称约定(SFN)的代字符(~)波浪号引起的。

它允许远程攻击者在Web根⽬录下公开⽂件和⽂件夹名称(不应该可被访问)。

攻击者可以找到通常⽆法从外部直接访问的重要⽂件,并获取有关应⽤程序基础结构的信息。

⼆、漏洞原理IIS的短⽂件名机制,可以暴⼒猜解短⽂件名,访问构造的某个存在的短⽂件名,会返回404,访问构造的某个不存在的短⽂件名,返回400。

漏洞成因:为了兼容16位MS-DOS程序,Windows为⽂件名较长的⽂件(和⽂件夹)⽣成了对应的windows 8.3短⽂件名。

在Windows下查看对应的短⽂件名,可以使⽤命令dir /x短⽂件名特征:1.只显⽰前6位的字符,后续字符⽤~1代替。

其中数字1是可以递增。

如果存在⽂件名类似的⽂件,则前⾯的6个字符是相同的,后⾯的数字进⾏递增2.后缀名最长只有3位,超过3位的会⽣成短⽂件名,且后缀多余的部分会截断。

3.所有⼩写字母均转换成⼤写的字母4.长⽂件名中包含多个”.”的时候,以⽂件最后⼀个”.”作为短⽂件名的后缀5.长⽂件名前缀/⽂件夹名字符长度符合0-9和A-Z、a-z范围且需要⼤于等于9位才会⽣成短⽂件名,如果包含空格或者其他部分特殊字符,不论长度均会⽣成短⽂件。

三、漏洞环境搭建及漏洞复现1、测试环境为windows server 2003 r2,开启webdav服务和net服务。

2、使⽤payload验证⽬标是否存在IIS短⽂件名漏洞,下图显⽰的404,说明⽬标存在该短⽂件名注:*可以匹配n个字符,n可以为03、浏览器访问⼀个不存在的短⽂件名,返回”Bad Request(400)”,说明⽬标不存在该短⽂件名4、通过浏览器访问上⾯两个payload,根据返回的结果,可以说明⽬标存在IIS短⽂件漏洞5、判断漏洞存在后,接下来⼿⼯详细分析猜解IIS短⽂件名原理5.1、在⽹站根⽬录(C:\Inetpub\wwwroot)下创建⼀个abcdef123456.txt⽂件5.3、通过以上两个图⽚,可以看出存在⼀个以a开头的短⽂件名5.7、⽤a-z的26个字母依次替换上述a的位置,当替换成t时,返回404页⾯,说明该短⽂件的第⼀位后缀是t5.8、按照上⾯的⽅法依次猜解得到该短⽂件名的后缀是txt5.9、到此为⽌,已经猜解出该短⽂件名为abcdef~1.txt6、根据已经猜解出来的短⽂件名abcdef~1.txt,继续猜解出该短⽂件名的完全⽂件名为abcdef123456.txt7、使⽤IIS短⽂件名扫描软件，获取⽬标存在哪些短⽂件名四、漏洞防御1、升级.net framework2、修改注册表键值：HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\FileSystem修改NtfsDisable8dot3NameCreation为1。

中国移动通信企业标准 家庭网关终端技术规范版本号：3.0.0 中国移动通信集团公司 发布╳╳╳╳-╳╳-╳╳发布 ╳╳╳╳-╳╳-╳╳实施 QB-╳╳-╳╳╳-╳╳╳╳T e c h n i c a l S p e c if i c a t i o n f o r H o m e G a t e w a y目录1. 范围 ................................................................................................................................................2. 规范性引用文件 .............................................................................................................................3. 术语、定义和缩略语 .....................................................................................................................4. 设备总体定义.................................................................................................................................4.1.设备在网络中的位置 ..................................................................................................................4.2.接口定义 ......................................................................................................................................4.3.设备类型 ......................................................................................................................................5. 接入型家庭网关 .............................................................................................................................5.1.接口要求 ......................................................................................................................................网络侧接口......................................................................................................................................网络侧接口描述..........................................................................................................................................网络侧以太网接口要求..............................................................................................................................接口要求 .......................................................................................................................................................接口要求 .......................................................................................................................................................接口要求 .......................................................................................................................................................用户侧接口......................................................................................................................................用户侧以太网接口要求..............................................................................................................................接口 ...............................................................................................................................................................接口（可选）................................................................................................................................................5.2.功能要求 ......................................................................................................................................数据通信要求..................................................................................................................................协议要求 .......................................................................................................................................................数据转发功能要求......................................................................................................................................功能要求 .......................................................................................................................................................地址管理及拨号管理功能要求....................................................................................................................地址管理及拨号管理功能要求....................................................................................................................要求 ...............................................................................................................................................................要求 ...............................................................................................................................................................组播要求 .....................................................................................................................................................其他功能要求..............................................................................................................................................安全要求..........................................................................................................................................防火墙 .........................................................................................................................................................登陆WEB页面的安全要求..........................................................................................................................设备安全性 .................................................................................................................................................要求....................................................................................................................................................功能要求............................................................................................................................................扩展及管理（可选）........................................................................................................................设备发现要求.........................................................................................................................................................................................................................................................................................................（可选） .......................................................................................................................................................支持WLAN的开启和禁用............................................................................................................................基本要求 .....................................................................................................................................................多SSID要求................................................................................................................................................安全要求 .......................................................................................................................................................5要求 ............................................................................................................................................................要求 ...............................................................................................................................................................基本应用要求................................................................................................................................... WLAN共享 ..................................................................................................................................................家庭存储（可选）......................................................................................................................................5.3.性能要求 ......................................................................................................................................路由转发性能要求..........................................................................................................................吞吐量 .........................................................................................................................................................地址学习 .....................................................................................................................................................缓存大小 (23)连接数量要求.............................................................................................................................................. 无线性能要求....................................................................................................................................吞吐量性能要求 (23)覆盖性能要求................................................................................................................................................接收灵敏度要求............................................................................................................................................5.4.管理和维护要求 (24)本地管理和配置要求......................................................................................................................本地管理基本要求......................................................................................................................................用户分级管理 (24)系统信息管理..............................................................................................................................................基本配置 .....................................................................................................................................................高级配置 .....................................................................................................................................................设备管理 .....................................................................................................................................................网络诊断 .....................................................................................................................................................设备认证注册功能......................................................................................................................................远程管理要求..................................................................................................................................远程管理基本要求......................................................................................................................................远程参数配置和性能监测..........................................................................................................................远程故障诊断功能......................................................................................................................................设备告警功能..............................................................................................................................................远程链路维持功能......................................................................................................................................软件远程管理..............................................................................................................................................业务部署和控制..........................................................................................................................................上行家庭网关远程管理实现方式 ................................................................................................................日志功能要求..................................................................................................................................5.5.预配置要求 ..................................................................................................................................预配置要求......................................................................................................................................5.6.硬件要求 ......................................................................................................................................基本要求..........................................................................................................................................硬件基本框图示例..........................................................................................................................5.7.软件要求 ......................................................................................................................................基本要求..........................................................................................................................................软件基本架构................................................................................................. 错误!未定义书签。

sip isregistered方法SIP（Session Initiation Protocol）是一种用于建立、修改和终止多媒体会话的通信协议。

其中的isRegistered方法是一种用于查询SIP用户注册状态的功能。

isRegistered方法的作用是检查特定的SIP地址是否已在SIP服务器上注册。

在SIP协议中，用户代理（User Agent）需要在发起或接收会话之前先向SIP服务器注册。

isRegistered方法可以帮助开发者确定某个SIP地址是否成功地完成了注册过程。

通过调用isRegistered方法，开发者可以判断一个特定的SIP用户是否在线和可用。

这对于实时通信应用程序尤其重要，因为它们需要准确地确定用户的在线状态。

isRegistered方法通常返回一个布尔值，如果指定的SIP地址已成功注册，则返回true；如果未注册或注册失败，则返回false。

使用isRegistered方法可以实现一些实用的功能。

例如，在一个即时通信应用程序中，可以利用这个方法来检查用户是否处于在线状态，并根据其状态来采取不同的操作，比如发送实时消息或者提示用户不在线。

对于开发者而言，使用isRegistered方法还需要注意以下几点：1. 需要提供合法的SIP地址作为参数，以便查询该地址的注册状态。

2. 在使用isRegistered方法前，需要确保已经建立了与SIP服务器的连接，并且获得了相应的权限。

3. 在处理方法返回的布尔值时，需要针对不同的情况进行逻辑判断和处理。

如果返回值为true，表示用户已经注册成功，可以进行相应的操作；如果返回值为false，可能需要通过其他方式提醒用户进行注册或重新尝试。

总之，SIP的isRegistered方法为开发者提供了快速查询SIP用户注册状态的功能。

通过合理利用这个方法，可以更好地实现实时通信应用程序，并提升用户体验。

the final error response in a provisional response. The Reason header
field is a candidate to be used for such encapsulation.
Schulzrinne, et. al. Standards Track [Page 2]
RFC 3326 The Reason Header Field for SIP December 2002
Initially, the Reason header field defined here appears to be most
useful for BYE and CANCEL requests, but it can appear in any request
6. Acknowledgments ............................................ 7
7. Authors' Addresses ......................................... 7
8. Normative References ....................................... 7
December 2002
The Reason Header Field for the Session Initiation Protocol (SIP)
Status of this Memo
3.4. ISUP interworking .......................................... 5
4. IANA Considerations ........................................ 6

SIP安全协议SIP（Session Initiation Protocol）是一种用于控制多媒体会话的协议，常用于互联网电话服务、语音和视频会议等领域。

由于其在传输过程中存在安全风险，因此需要采取相应的安全协议来保护通信内容和用户身份信息。

本文将介绍几种常见的SIP安全协议和其工作原理。

一、SIP中的安全问题SIP作为一种应用层协议，其安全问题主要包括信息泄露、拒绝服务攻击和身份伪造等。

攻击者可以通过监听SIP通信获取用户信息，篡改通信内容或阻断通信服务。

为了解决这些问题，SIP安全协议应运而生。

二、S/MIME（Secure/Multipurpose Internet Mail Extensions）S/MIME是一种基于公钥加密的SIP安全协议。

它通过数字证书将加密和签名应用于SIP会话中的消息，确保消息的机密性和完整性。

S/MIME使用RSA算法对会话进行加密，并通过数字签名验证发送者的身份。

这种方式能够有效地防止信息泄露和身份伪造等问题。

三、TLS（Transport Layer Security）TLS是一种传输层安全协议，在SIP通信中主要用于建立安全的传输通道。

它通过握手过程实现通信双方的身份验证，并使用对称加密算法保护数据的机密性。

TLS能够有效地抵御监听和中间人攻击等安全威胁，提供安全可靠的通信环境。

四、SIP认证机制SIP认证机制是一种基于用户名和密码的安全协议，用于防止未经授权的访问。

当用户发起SIP会话时，需要提供正确的用户名和密码进行认证。

常见的SIP认证机制包括基本认证（Basic Authentication）和摘要认证（Digest Authentication）。

这种方式可以防止身份伪造和未授权访问等风险。

五、防止拒绝服务攻击拒绝服务攻击是SIP通信中的一种常见威胁，攻击者通过发送大量无效请求或僵尸请求，使得服务无法正常处理合法请求。

为了解决这个问题，可以采用带宽限制、请求频率控制和会话授权等策略来限制恶意请求的影响，保证正常用户的通信质量。

Network Working Group R. Mahy Request for Comments: 3891 Cisco Systems, Inc. Category: Standards Track B. Biggs R. Dean September 2004 The Session Initiation Protocol (SIP) "Replaces" HeaderStatus of this MemoThis document specifies an Internet standards track protocol for the Internet community, and requests discussion and suggestions forimprovements. Please refer to the current edition of the "InternetOfficial Protocol Standards" (STD 1) for the standardization stateand status of this protocol. Distribution of this memo is unlimited.Copyright NoticeCopyright (C) The Internet Society (2004).AbstractThis document defines a new header for use with Session InitiationProtocol (SIP) multi-party applications and call control. TheReplaces header is used to logically replace an existing SIP dialogwith a new SIP dialog. This primitive can be used to enable avariety of features, for example: "Attended Transfer" and "CallPickup". Note that the definition of these example features is non- normative.Mahy, et al. Standards Track [Page 1]Table of Contents1. Overview. . . . . . . . . . . . . . . . . . . . . . . . . . . 22. Conventions . . . . . . . . . . . . . . . . . . . . . . . . . 43. User Agent Server Behavior: Receiving a Replaces Header . . . 44. User Agent Client Behavior: Sending a Replaces Header . . . . 65. Proxy Behavior. . . . . . . . . . . . . . . . . . . . . . . . 76. Syntax. . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 6.1. The Replaces Header . . . . . . . . . . . . . . . . . . 76.2. New Option Tag for Require and Supported Headers. . . . 87. Usage Examples. . . . . . . . . . . . . . . . . . . . . . . . 97.1. Replacing an Early Dialog at the Originator . . . . . . 98. Security Considerations . . . . . . . . . . . . . . . . . . . 119. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 13 9.1. Registration of "Replaces" SIP Header . . . . . . . . . 139.2. Registration of "replaces" SIP Option-tag . . . . . . . 1310. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 1311. References. . . . . . . . . . . . . . . . . . . . . . . . . . 13 11.1. Normative References. . . . . . . . . . . . . . . . . . 1311.2. Informative References. . . . . . . . . . . . . . . . . 1412. Authors’ Addresses. . . . . . . . . . . . . . . . . . . . . . 1513. Full Copyright Statement. . . . . . . . . . . . . . . . . . . 16 1. OverviewThis document describes a SIP [1] extension header field as part ofthe SIP multiparty applications architecture framework [10]. TheReplaces header is used to logically replace an existing SIP dialogwith a new SIP dialog. This is especially useful in peer-to-peercall control environments.One use of the "Replaces" header is to replace one participant withanother in a multimedia conversation. While this functionality isalready available using 3rd party call control [11] style callcontrol, the 3pcc model requires a central point of control which may not be desirable in many environments. As such, a method ofperforming these same call control primitives in a distributed,peer-to-peer fashion is very desirable.Use of a new INVITE with a new header for dialog matching was chosen over making implicit associations in an incoming INVITE based oncall-id or other fields for the following reasons:o An INVITE already has the correct semantics for a new callo Using an explicit Replaces header in a new request makes theintent of the request obvious.Mahy, et al. Standards Track [Page 2]o A unique call-id may be given to the replacement call. Thisavoids dialog matching problems in any of the related User Agents. o There are no adverse effects if the header is unsupported.The Replaces header enables services such as attended call transfer, retrieve from park, and transition from locally mixed conferences to two party calls in a distributed peer-to-peer way. This list ofservices is not exhaustive. Although the Replaces header isfrequently used in combination with the REFER [8] method as used in a Transfer [12], they may be used independently.For example, Alice is talking to Bob from phone1. She transfers Bob to a Parking Place while she goes to the lab. When she gets thereshe retrieves the "parked" call from phone2 by sending an INVITE with a Replaces header field to Bob with the dialog information Bob shared with the Parking Place. Alice got this information using some out of band mechanism. Perhaps she subscribed to this information from the Parking Place (using the session dialog package [13]), or went to awebsite and clicked on a URI. A short call flow for this examplefollows. (Via and Max-Forwards headers are omitted for clarity.)Alice Alice Parkingphone1 phone2 Bob Place| | | ||<===============================>| || | | || Alice transfers Bob to Parking Place || | | ||------------REFER/200----------->| *1 *2 ||<--NOTIFY/200 (trying)-----------|--INVITE/200/ACK-->||<--NOTIFY/200 (success)----------|<=================>||------------BYE/200------------->| || | | || | | || Alice later retrieves call from another phone || | | || *3 |-INV w/Replaces->| || |<--200-----------| || |---ACK---------->|----BYE/200------->|| |<===============>| || | | |Mahy, et al. Standards Track [Page 3]Message *1: Bob-> Parking PlaceINVITE sip:parkingplace@ SIP/2.0To: <sip:parkingplace@>From: <sip:bob@>;tag=7743Call-ID: 425928@CSeq: 1 INVITEContact: <sip:bob@>Referred-By: <sip:alice@>Message *2: Parking Place -> BobSIP/2.0 200 OKTo: <sip:parkingplace@>;tag=6472From: <sip:bob@>;tag=7743Call-ID: 425928@CSeq: 1 INVITEContact: <sip:parkplace@>Message *3: Alice@phone2 -> BobINVITE sip:bob@To: <sip:bob@>From: <sip:alice@>;tag=8983Call-ID: 09870@CSeq: 1 INVITEContact: <sip:alice@>Require: replacesReplaces: 425928@;to-tag=7743;from-tag=64722. ConventionsThe key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT","SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in BCP 14, RFC 2119 [2]. This document refers frequently to the terms "confirmed dialog" and"early dialog". These are defined in Section 12 of SIP [1].3. User Agent Server Behavior: Receiving a Replaces HeaderThe Replaces header contains information used to match an existingSIP dialog (call-id, to-tag, and from-tag). Upon receiving an INVITE with a Replaces header, the User Agent (UA) attempts to match thisinformation with a confirmed or early dialog. The User Agent Server (UAS) matches the to-tag and from-tag parameters as if they were tags Mahy, et al. Standards Track [Page 4]present in an incoming request. In other words, the to-tag parameter is compared to the local tag, and the from-tag parameter is compared to the remote tag.If more than one Replaces header field is present in an INVITE, or if a Replaces header field is present in a request other than INVITE,the UAS MUST reject the request with a 400 Bad Request response.The Replaces header has specific call control semantics. If both aReplaces header field and another header field with contradictorysemantics are present in a request, the request MUST be rejected with a 400 "Bad Request" response.If the Replaces header field matches more than one dialog, the UAMUST act as if no match is found.If no match is found, the UAS rejects the INVITE and returns a 481Call/Transaction Does Not Exist response. Likewise, if the Replaces header field matches a dialog which was not created with an INVITE,the UAS MUST reject the request with a 481 response.If the Replaces header field matches a dialog which has alreadyterminated, the UA SHOULD decline the request with a 603 Declinedresponse. (If the matched invitation was just terminated, thereplacement request should fail as well. Declining the request with a 600-class response prevents an irritating race-condition where the UA rings or alerts for a replacement call which is not wanted.)If the Replaces header field matches an active dialog, the UA MUSTverify that the initiator of the new INVITE is authorized to replace the matched dialog. If the initiator of the new INVITE has beensuccessfully authenticated as equivalent to the user who is beingreplaced, then the replacement is authorized. For example, if theuser being replaced and the initiator of the replacement dialog share the same credentials for Digest authentication [6], or they sign the replacement request with S/MIME [7] with the same private key andpresent the (same) corresponding certificate used in the originaldialog, then the replacement is authorized.Alternatively, the Referred-By mechanism [4] defines a mechanism that the UAS can use to verify that a replacement request was sent onbehalf of the other participant in the matched dialog (in this case, triggered by a REFER request). If the replacement request contains a Referred-By header that corresponds to the user being replaced, theUA SHOULD treat the replacement as if the replacement was authorized by the replaced party. The Referred-By header SHOULD reference acorresponding, valid Refererred-By Authenticated Identity Body [5]. Mahy, et al. Standards Track [Page 5]The UA MAY apply other local policy to authorize the remainder of the request. In other words, the UAS may apply a different policy to the replacement dialog than was applied to the replaced dialog.In addition, the UA MAY use other authorization mechanisms definedfor this purpose in standards track extensions. Extensions coulddefine other mechanisms for transitively asserting authorization of a replacement.If authorization is successful, the UA attempts to accept the newINVITE, reassign the user interface and other resources of thematched dialog to the new INVITE, and shut down the replaced dialog. If the UA cannot accept the new INVITE (for example: it cannotestablish required QoS or keying, or it has incompatible media), the UA MUST return an appropriate error response and MUST leave thematched dialog unchanged.If the Replaces header field matches a confirmed dialog, it checksfor the presence of the "early-only" flag in the Replaces headerfield. (This flag allows the UAC to prevent a potentiallyundesirable race condition described in Section 7.1.) If the flag is present, the UA rejects the request with a 486 Busy response.Otherwise, it accepts the new INVITE by sending a 200-class response, and shuts down the replaced dialog by sending a BYE. If the Replaces header field matches an early dialog that was initiated by the UA, it accepts the new INVITE by sending a 200-class response, and shutsdown the replaced dialog by sending a CANCEL.If the Replaces header field matches an early dialog that was notinitiated by this UA, it returns a 481 (Call/Transaction Does NotExist) response to the new INVITE, and leaves the matched dialogunchanged. Note that since Replaces matches only a single dialog,the replacement dialog will not be retargeted according to the sameforking logic as the original request which created the early dialog. (Currently, no use cases have been identified for replacing just asingle dialog in this circumstance.)4. User Agent Client Behavior: Sending a Replaces HeaderA User Agent that wishes to replace a single existing early orconfirmed dialog with a new dialog of its own, MAY send the targetUser Agent an INVITE request containing a Replaces header field. The User Agent Client (UAC) places the Call-ID, to-tag, and from-taginformation for the target dialog in a single Replaces header fieldand sends the new INVITE to the target. If the user agent onlywishes to replace an early dialog (as in the Call Pickup example inSection 7.1), the UAC MAY also include the "early-only" parameter in Mahy, et al. Standards Track [Page 6]the Replaces header field. A UAC MUST NOT send an INVITE with aReplaces header field that attempts to replace an early dialog which was not originated by the target of the INVITE with a Replaces header field.Note that use of this mechanism does not provide a way to matchmultiple dialogs, nor does it provide a way to match an entire call, an entire transaction, or to follow a chain of proxy forking logic.For example, if Alice replaces Cathy in an early dialog with Bob, but Bob does not answer, Alice’s replacement request will not match other dialogs to which Bob’s UA redirects, nor other branches to which his proxy forwards. Although this specification takes reasonableprecautions to prevent unexpected behavior in the face of forking,implementations SHOULD only address replacement requests (i.e., setthe Request-URI of the replacement request) to the SIP Contact URI of the target.5. Proxy behaviorProxy Servers do not require any new behavior to support thisextension. They simply pass the Replaces header field transparently as described in the SIP specification.Note that it is possible for a proxy (especially when forking basedon some application layer logic, such as caller screening or time-of-day routing) to forward an INVITE request containing a Replacesheader field to a completely orthogonal set of Contacts other thanthe original request it was intended to replace. In this case, theINVITE request with the Replaces header field will fail.6. Syntax6.1. The Replaces HeaderThe Replaces header field indicates that a single dialog identifiedby the header field is to be shut down and logically replaced by the incoming INVITE in which it is contained. It is a request headeronly, and defined only for INVITE requests. The Replaces headerfield MAY be encrypted as part of end-to-end encryption. Only asingle Replaces header field value may be present in a SIP request.This document adds the following entry to Table 2 of [1]. Additions to this table are also provided for extension methods defined at the time of publication of this document. This is provided as a courtesy to the reader and is not normative in any way. MESSAGE, SUBSCRIBEand NOTIFY, REFER, INFO, UPDATE, PRACK, and PUBLISH are definedrespectively in [15], [16], [8], [17], [18], [19], and [20].Mahy, et al. Standards Track [Page 7]Header field where proxy ACK BYE CAN INV OPT REG MSG ------------ ----- ----- --- --- --- --- --- --- --- Replaces R - - - o - - -SUB NOT REF INF UPD PRA PUB --- --- --- --- --- --- --- Replaces R - - - - - - -The following syntax specification uses the augmented Backus-NaurForm (BNF) as described in RFC 2234 [3]. The syntax below relies on a number of productions from SIP [1].Replaces = "Replaces" HCOLON callid *(SEMI replaces-param) replaces-param = to-tag / from-tag / early-flag / generic-paramto-tag = "to-tag" EQUAL tokenfrom-tag = "from-tag" EQUAL tokenearly-flag = "early-only"A Replaces header field MUST contain exactly one to-tag and exactlyone from-tag, as they are required for unique dialog matching. Forcompatibility with dialogs initiated by RFC 2543 [9] compliant UAs, a tag of zero matches both tags of zero and null. A Replaces headerfield MAY contain the early-flag.Examples:Replaces: 98732@;from-tag=r33th4x0r;to-tag=ff87ffReplaces: 12adf2f34456gs5;to-tag=12345;from-tag=54321;early-onlyReplaces: 87134@171.161.34.23;to-tag=24796;from-tag=06.2. New Option Tag for Require and Supported HeadersThis specification defines a new Require/Supported header option tag "replaces". UAs which support the Replaces header MUST include the"replaces" option tag in a Supported header field. UAs that wantexplicit failure notification if Replaces is not supported MAYinclude the "replaces" option in a Require header field.Example:Require: replaces, 100relMahy, et al. Standards Track [Page 8]7. Usage ExamplesThe following non-normative examples are not intended to enumerateall the possibilities for the usage of this extension, but rather to provide examples or ideas only. For more examples, please see SIPService Examples [14]. Via and Max-Forwards headers are omitted for clarity and brevity.7.1. Replacing an Early Dialog at the OriginatorIn this example, Bob just arrived in the lab and hasn’t registeredthere yet. He hears his desk phone ring. He quickly logs into asoftware UA on a nearby computer. Among other things, the softwareUA has access to the dialog state of his desk phone. When it notices that his phone is ringing, it offers him the choice of taking thecall there. The software UA sends an INVITE with Replaces to Alice. When Alice’s UA receives this new INVITE, it CANCELs her originalINVITE and connects Alice to Bob.Bob BobAlice desk lab| | |*1 |-----INVITE----------->| |*2 |<----180---------------| Bob hears desk phone || | ringing from lab but || | isn’t REGISTERed yet || | || |<--fetch dialog state --|| |---response ----------->|*3/4 |<-----INVITE with Replaces/200/ACK--------------|*5/6 |------CANCEL/200------>| |*7 |<-----487--------------| ||------ACK------------->| || | || | |Message *1: Alice -> Bob’s desk phoneINVITE sip:bob@ SIP/2.0To: <sip:bob@>From: <sip:alice@>;tag=7743Call-ID: 425928@CSeq: 1 INVITEContact: <sip:alice@>Mahy, et al. Standards Track [Page 9]Message *2: Bob’s desk phone -> AliceSIP/2.0 180 RingingTo: <sip:bob@>;tag=6472From: <sip:alice@>;tag=7743Call-ID: 425928@CSeq: 1 INVITEContact: <sip:bob@>Message *3: Bob in lab -> AliceINVITE sip:alice@To: <sip:alice@>From: <sip:bob@>;tag=8983Call-ID: 09870@CSeq: 1 INVITEContact: <sip:bob@>Replaces: 425928@;to-tag=7743;from-tag=6472;early-onlyMessage *4: Alice -> Bob in labSIP/2.0 200 OKTo: <sip:alice@>;tag=9232From: <sip:bob@>;tag=8983Call-ID: 09870@CSeq: 1 INVITEContact: <sip:alice@>Message *5: Alice -> Bob’s deskCANCEL sip:bob@ SIP/2.0To: <sip:bob@>From: <sip:alice@>;tag=7743Call-ID: 425928@CSeq: 1 CANCELContact: <sip:alice@>Message *6: Bob’s desk -> AliceSIP/2.0 200 OKTo: <sip:bob@>From: <sip:alice@>;tag=7743Call-ID: 425928@CSeq: 1 CANCELContact: <sip:bob@>Mahy, et al. Standards Track [Page 10]Message *7: Bob’s desk -> AliceSIP/2.0 487 Request TerminatedTo: <sip:bob@>;tag=6472From: <sip:alice@>;tag=7743Call-ID: 425928@CSeq: 1 INVITE8. Security ConsiderationsThe extension specified in this document significantly changes therelative security of SIP devices. Currently in SIP, even if aneavesdropper learns the Call-ID, To, and From headers of a dialog,they cannot easily modify or destroy that dialog if Digestauthentication or end-to-end message integrity are used.This extension can be used to disconnect participants or replaceparticipants in a multimedia conversation. As such, invitations with the Replaces header MUST only be accepted if the peer requestingreplacement has been properly authenticated using a standard SIPmechanism (Digest or S/MIME), and authorized to request a replacement of the target dialog. All SIP implementations are already requiredto support Digest Authentication. In addition, implementations which support the Replaces header SHOULD also implement the Referred-Bymechanism.How a User Agent determines which requests are legitimatelyauthorized to make dialog replacements is non-trivial and depends on a considerable amount of local policy configuration. In general,there are four cases when an authorization for a replacement isreasonable or warranted.1. Replacement made by a party considered equivalent to the replaced party2. Replacement made on behalf of the replaced party (perhapstransitively)3. Replacement made by a former participant4. Replacement made by a specifically authorized partyStarting with #1 for example, if an executive and an assistant bothreceive requests for a shared address-of-record, if so configured,either should be able to replace dialogs of the other for the shared identity. Both could even share the same keying material (Digest or S/MIME), or one could hold an authorization document signed by the Mahy, et al. Standards Track [Page 11]other expressing this relationship. Likewise, in a call centerenvironment, each call center agent could possess credentials towhich supervisors also have access.The most common use case of a replacement is on the request of thereplaced participant (who no longer wants to be involved). This isthe case in many features, such as completing an Attended Transferand converting a 3-way call to a point-to-point call. Suchreplacements are typically triggered by a REFER [8] request from the replaced participant. The Referred-By [4] mechanism defines one way to identify the apparent original requester and can point to a SIPAuthenticated Identity Body [5] (an S/MIME-based signed assertion) to secure this information.In the example in section 1, Alice sends an INVITE with Replaces toBob. Alice was a former participant in the conversation and had aprevious dialog relationship with Bob. Alice can use the same Digest or S/MIME credentials she used to authenticate with Bob during theoriginal call to prove that she was a former participant. Note that this justification for replacing calls is more dangerous than theothers, and in most cases is another way to authorize that thereplacing participant is available. Implementations SHOULD NOT rely on this method as an authorization mechanism.The last scenario is the easiest to secure but the least likely to be useful in practice. It is unlikely that an arbitrary host in theInternet is aware of any special authorization relationship betweenthe replaced and the replacing parties. However, this use case maybe useful in some environments. Since this usage does noteffectively degrade the security of the solution, it is stillallowed.Some mechanisms for obtaining the dialog information needed by theReplaces header (Call-ID, to-tag, and from-tag) include URIs on a web page, subscriptions to an appropriate event package, andnotifications after a REFER request. Since manipulating this dialog information could cause User Agents to replace the wrong dialog, use of message integrity protection for this information is STRONGLYRECOMMENDED. Use of end-to-end security mechanisms to encrypt thisinformation is also RECOMMENDED.This extension was designed to take advantage of future signature or authorization schemes defined in standards track extensions. Ingeneral, call control features benefit considerably from such work. Mahy, et al. Standards Track [Page 12]9. IANA Considerations9.1. Registration of "Replaces" SIP headerName of Header: ReplacesShort form: noneNormative description: section 6.1 of this document9.2. Registration of "replaces" SIP Option-tagName of option: replacesDescription: Support for the SIP Replaces headerSIP headers defined: ReplacesNormative description: This document10. AcknowledgmentsThanks to Robert Sparks, Alan Johnston, Dan Petrie, Ben Campbell, and many other members of the SIP WG for their continued support of thecause of distributed call control in SIP.11. References11.1. Normative References[1] Rosenberg, J., Schulzrinne, H., Camarillo, G., Johnston, A.,Peterson, J., Sparks, R., Handley, M., and E. Schooler, "SIP:Session Initiation Protocol", RFC 3261, June 2002.[2] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997.[3] Crocker, D. and P. Overell, "Augmented BNF for SyntaxSpecifications: ABNF", RFC 2234, November 1997.[4] Sparks, R., "The Session Initiation Protocol (SIP) Referred-ByMechanism", RFC 3892, September 2004.[5] Peterson, J., "The Session Initiation Protocol (SIP)Authenticated Identity Body (AIB) Format", RFC 3893, September2004.Mahy, et al. Standards Track [Page 13][6] Franks, J., Hallam-Baker, P., Hostetler, J., Lawrence, S.,Leach, P., Luotonen, A., and L. Stewart, "HTTP Authentication:Basic and Digest Access Authentication", RFC 2617, June 1999.[7] Ramsdell, B., "Secure/Multipurpose Internet Mail Extensions(S/MIME) Version 3.1 Message Specification", RFC 3851, July2004.11.2. Informative References[8] Sparks, R., "The Session Initiation Protocol (SIP) ReferMethod", RFC 3515, April 2003.[9] Handley, M., Schulzrinne, H., Schooler, E., and J. Rosenberg,"SIP: Session Initiation Protocol", RFC 2543, March 1999.[10] Mahy, R., "A Call Control and Multi-party usage framework forthe Session Initiation Protocol (SIP)", Work in Progress, March 2003.[11] Rosenberg, J., Peterson, J., Schulzrinne, H., and G. Camarillo, "Best Current Practices for Third Party Call Control (3pcc) inthe Session Initiation Protocol (SIP)", BCP 85, RFC 3725, April 2004.[12] Sparks, R. and A. Johnston, "Session Initiation Protocol CallControl - Transfer", Work in Progress, February 2003.[13] Rosenberg, J. and H. Schulzrinne, "An INVITE Initiated DialogEvent Package for the Session Initiation Protocol (SIP)", Workin Progress, March 2003.[14] Johnston, A. and S. Donovan, "Session Initiation ProtocolService Examples", Work in Progress, March 2003.[15] Campbell, B., Rosenberg, J., Schulzrinne, H., Huitema, C., andD. Gurle, "Session Initiation Protocol (SIP) Extension forInstant Messaging", RFC 3428, December 2002.[16] Roach, A., "Session Initiation Protocol (SIP)-Specific EventNotification", RFC 3265, June 2002.[17] Donovan, S., "The SIP INFO Method", RFC 2976, October 2000.[18] Rosenberg, J., "The Session Initiation Protocol (SIP) UPDATEMethod", RFC 3311, October 2002.Mahy, et al. Standards Track [Page 14][19] Rosenberg, J. and H. Schulzrinne, "Reliability of ProvisionalResponses in Session Initiation Protocol (SIP)", RFC 3262, June 2002.[20] Campbell, B., "SIMPLE Presence Publication Mechanism", Work inProgress, February 2003.12. Authors’ AddressesRohan MahyCisco Systems, Inc.5617 Scotts Valley DrScotts Valley, CA 95066USAEMail: rohan@Billy BiggsEMail: bbiggs@Rick DeanEMail: rfc@Mahy, et al. Standards Track [Page 15]13. Full Copyright StatementCopyright (C) The Internet Society (2004).This document is subject to the rights, licenses and restrictionscontained in BCP 78, and except as set forth therein, the authorsretain all their rights.This document and the information contained herein are provided on an "AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/S HEREPRESENTS OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY AND THE INTERNET ENGINEERING TASK FORCE DISCLAIM ALL WARRANTIES, EXPRESS ORIMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OFTHE INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIEDWARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. Intellectual PropertyThe IETF takes no position regarding the validity or scope of anyIntellectual Property Rights or other rights that might be claimed to pertain to the implementation or use of the technology described inthis document or the extent to which any license under such rightsmight or might not be available; nor does it represent that it hasmade any independent effort to identify any such rights. Information on the IETF’s procedures with respect to rights in IETF Documents can be found in BCP 78 and BCP 79.Copies of IPR disclosures made to the IETF Secretariat and anyassurances of licenses to be made available, or the result of anattempt made to obtain a general license or permission for the use of such proprietary rights by implementers or users of thisspecification can be obtained from the IETF on-line IPR repository at /ipr.The IETF invites any interested party to bring to its attention anycopyrights, patents or patent applications, or other proprietaryrights that may cover technology that may be required to implementthis standard. Please address the information to the IETF at ietf-ipr@.AcknowledgementFunding for the RFC Editor function is currently provided by theInternet Society.Mahy, et al. Standards Track [Page 16]。

最佳实践上报表
问题编号
设备/终端厂家
中兴
设备/终端类型
所属专业
无线网
问题类型
参数类
问题级别
重要
上报省份
福建
上报人
黄盛宏
上报时间
2020-11-17
问题名称
及现象概述
《NSSAI设置错误导致SA接入》
问题描述
新开SA_NSA双模宏站，A9631A S26，外场单验SA无法接入，现建立失败。
3.初步核查切片相关配置，发现SliceProfile只配置了一条，然而本站有拉远站，并且拉远站的TAC有变更，因此需新增一条SliceProfile配置。查看NSSAI配置了两条，SST配置为1，SD都改为与核心网对应的值，还是无法接入。
4.继续核查切片参数，发现两条NSSAI关联到同一条Slice ProFile，修改切片关联后接入正常。
解决方案
详细说明
问题分析
接入问题一般从站点告警，SA的SCTP链路，NGAP偶联，随机接入参数，切片配置等参数进行核查。根据现场信令，SA随机接入流程MSG1到5正常，说明RACH参数配置无误，因此需要重点针对SA专有参数进行核查。
解决方案
1.核查站点无告警，无干扰。
2.核查SA链路，配置了到5GC的链路，也有NGAP的引用。
正确配置：
本省应
用成效
目前外场遇到SA接入问题较多还是切片配置，该参数在开站时产品侧就会配置，因此网优侧需要与产品侧及时做好沟通，保证该参数的准确性。需要注意在有拉远站时，并且TAC变更的情况下需要对每个TAC配置一条切片配置。并且核查站点TAC和切片内配置TAC的一致性。
备注

SSLTLS会话重放攻击防护SSL/TLS会话重放攻击防护SSL/TLS（Secure Socket Layer/Transport Layer Security）是一种常用的加密传输协议，用于保护互联网上的数据传输安全。

然而，正如所有的安全措施都有漏洞一样，SSL/TLS协议也存在一些安全威胁，其中之一就是会话重放攻击（session replay attack）。

本文将介绍SSL/TLS会话重放攻击的原理和影响，并提供一些有效的防护方法。

一、会话重放攻击原理会话重放攻击是一种被动攻击方式，攻击者通过拦截和记录SSL/TLS会话的加密数据，然后重新发送这些数据来重放会话。

攻击者可以通过拦截网络流量或对受害者发起中间人攻击来获取会话数据。

在一个成功的会话重放攻击中，攻击者重播先前捕获的有效SSL/TLS数据，目标系统会误认为这是合法的请求，从而执行相关操作。

这可能导致各种问题，例如身份盗窃、账户劫持、非法操作等。

二、会话重放攻击的危害1. 身份盗窃：攻击者可以获取合法用户的登录凭证、会话令牌等敏感信息，进而冒充用户身份进行非法操作。

2. 资金损失：如果涉及到金融交易，攻击者可以利用会话重放攻击完成支付、转账等操作，导致用户经济损失。

3. 机密信息泄露：攻击者可以拦截敏感数据的会话，例如信用卡号、密码等，从而泄露用户隐私。

4. 业务中断：会话重放攻击可导致系统或应用服务不可用，造成业务中断，影响用户体验和声誉。

三、防护措施为了有效抵御SSL/TLS会话重放攻击，以下是一些常见的防护措施：1. 加密会话数据：使用加密算法对会话数据进行加密处理，确保数据传输的机密性和完整性，使攻击者无法理解、篡改和重播会话数据。

2. 使用唯一的会话标识符：在每个会话中，使用唯一且不可预测的标识符来识别和验证会话，例如使用随机数或时间戳构建会话ID。

3. 时间戳和序列号：为会话数据设置时间戳和序列号，服务器在接收到请求时检查其有效性，拒绝处理已过期或重复的请求。

Internet Engineering Task Force (IETF) K. Drage Request for Comments: 6050 Alcatel-Lucent Category: Informational November 2010 ISSN: 2070-1721A Session Initiation Protocol (SIP) Extensionfor the Identification of ServicesAbstractThis document describes private extensions to the Session Initiation Protocol (SIP) that enable a network of trusted SIP servers to assert the service of authenticated users. The use of these extensions isonly applicable inside an administrative domain with previouslyagreed-upon policies for generation, transport, and usage of suchinformation. This document does NOT offer a general serviceidentification model suitable for use between different trust domains or for use in the Internet at large.The document also defines a URN to identify both services and UserAgent (UA) applications. This URN can be used within the SIP header fields defined in this document to identify services, and also within the framework defined for caller preferences and callee capabilities to identify usage of both services and applications between end UAs.Status of This MemoThis document is not an Internet Standards Track specification; it is published for informational purposes.This document is a product of the Internet Engineering Task Force(IETF). It represents the consensus of the IETF community. It hasreceived public review and has been approved for publication by theInternet Engineering Steering Group (IESG). Not all documentsapproved by the IESG are a candidate for any level of InternetStandard; see Section 2 of RFC 5741.Information about the current status of this document, any errata,and how to provide feedback on it may be obtained at/info/rfc6050.Drage Informational [Page 1]Copyright NoticeCopyright (c) 2010 IETF Trust and the persons identified as thedocument authors. All rights reserved.This document is subject to BCP 78 and the IETF Trust’s LegalProvisions Relating to IETF Documents(/license-info) in effect on the date ofpublication of this document. Please review these documentscarefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e ofthe Trust Legal Provisions and are provided without warranty asdescribed in the Simplified BSD License.Table of Contents1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 32. Applicability Statement . . . . . . . . . . . . . . . . . . . 53. Conventions . . . . . . . . . . . . . . . . . . . . . . . . . 64. Syntax of the Header Fields . . . . . . . . . . . . . . . . . 6 4.1. The P-Asserted-Service Header . . . . . . . . . . . . . . 6 4.2. The P-Preferred-Service Header . . . . . . . . . . . . . . 7 4.3. Service and Application Definition . . . . . . . . . . . . 84.4. Registration Template . . . . . . . . . . . . . . . . . . 85. Usage of the P-Preferred-Service and P-Asserted-ServiceHeader Fields . . . . . . . . . . . . . . . . . . . . . . . . 10 5.1. Usage of the P-Preferred-Service andP-Asserted-Service Header Fields in Requests . . . . . . . 10 5.1.1. Procedures at User Agent Clients (UAC) . . . . . . . . 10 5.1.2. Procedures at Intermediate Proxies . . . . . . . . . . 11 5.1.3. Procedures at User Agent Servers . . . . . . . . . . . 12 5.2. Usage of the P-Preferred-Service andP-Asserted-Service Header Fields in Responses . . . . . . 126. Examples of Usage . . . . . . . . . . . . . . . . . . . . . . 127. Security Considerations . . . . . . . . . . . . . . . . . . . 158. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 16 8.1. P-Asserted-Service and P-Preferred-Service HeaderFields . . . . . . . . . . . . . . . . . . . . . . . . . . 168.2. Definition of Service-ID Values . . . . . . . . . . . . . 169. References . . . . . . . . . . . . . . . . . . . . . . . . . . 17 9.1. Normative References . . . . . . . . . . . . . . . . . . . 17 9.2. Informative References . . . . . . . . . . . . . . . . . . 18 Drage Informational [Page 2]1. IntroductionThis document describes private extensions to the Session Initiation Protocol (SIP) that enable a network of trusted SIP servers to assert the service, possibly subject to the user being entitled to thatservice. The use of these extensions is only applicable inside anadministrative domain with previously agreed-upon policies forgeneration, transport, and usage of such information. This document does NOT offer a general service model suitable for use betweendifferent trust domains or for use in the Internet at large.The concept of "service" within SIP has no hard and fast rules. RFC 5897 [RFC5897] provides general guidance on what constitutes aservice within SIP and what does not.This document also makes use of the terms "derived serviceidentification" and "declarative service identification" as definedin RFC 5897 [RFC5897].It should be noted that RFC 5897 [RFC5897] clearly states thatdeclarative service identification -- the process by which a useragent inserts a moniker into a message that defines the desiredservice, separate from explicit and well-defined protocol mechanisms -- is harmful.During a session setup, proxies may need to understand what servicethe request is related to in order to know what application server to contact or other service logic to invoke. The SIP INVITE requestcontains all of the information necessary to determine the service.However, the calculation of the service may be computational anddatabase intensive. For example, a given trust domain’s definitionof a service might include request authorization. Moreover, theanalysis may require examination of the Session Description Protocol (SDP).For example, an INVITE request with video SDP directed to a video-on- demand Request-URI could be marked as an IPTV session. An INVITErequest with push-to-talk over cellular (PoC) routes could be marked as a PoC session. An INVITE request with a Require header fieldcontaining an option tag of "foogame" could be marked as a foogamesession.NOTE: If the information contained within the SIP INVITE request isnot sufficient to uniquely identify a service, the remedy is toextend the SIP signaling to capture the missing element. RFC 5897[RFC5897] provides further explanation.Drage Informational [Page 3]By providing a mechanism to compute and store the results of thedomain-specific service calculation, i.e., the derived serviceidentification, this optimization allows a single trusted proxy toperform an analysis of the request and authorize the requestor’spermission to request such a service. The proxy may then include aservice identifier that relieves other trusted proxies and trustedUAs from performing further duplicate analysis of the request fortheir service identification purposes. In addition, this extensionallows user agent clients outside the trust domain to provide a hint of the requested service.This extension does not provide for the dialog or transaction to berejected if the service is not supported end-to-end. SIP providesother mechanisms, such as the option-tag and use of the Require andProxy-Require header fields, where such functionality is required.No explicitly signaled service identification exists, and the session proceeds for each node’s definition of the service in use, on thebasis of information contained in the SDP and in other SIP headerfields.This mechanism is specifically for managing the information needs of intermediate routing devices between the calling user and the userrepresented by the Request-URI. In support of this mechanism, a URN is defined to identify the services. This URN has widerapplicability to additionally identify services and terminalapplications. Between end users, caller preferences and calleecapabilities as specified in RFC 3840 [RFC3840] and RFC 3841[RFC3841] provide an appropriate mechanism for indicating suchservice and application identification. These mechanisms have beenextended by RFC 5688 [RFC5688] to provide further capabilities inthis area.The mechanism proposed in this document relies on a new header field called ’P-Asserted-Service’ that contains a URN. This is supportedby a further new header field called ’P-Preferred-Service’ that also contains a URN and that allows the UA to express preferencesregarding the decisions made on service within the trust domain.An example of the P-Asserted-Service header field is:P-Asserted-Service: urn:urn-7:3gpp-service.exampletelephony.version1 A proxy server that handles a request can, after authenticating theoriginating user in some way (for example: digest authentication) to ensure that the user is entitled to that service, insert such aP-Asserted-Service header field into the request and forward it to Drage Informational [Page 4]other trusted proxies. A proxy that is about to forward a request to a proxy server or UA that it does not trust removes all theP-Asserted-Service header field values.This document labels services by means of an informal URN. Thisprovides a hierarchical structure for defining services andsubservices, and provides an address that can be resolvable forvarious purposes outside the scope of this document, e.g., to obtain information about the service so described.2. Applicability StatementThis document describes private extensions to SIP (see RFC 3261[RFC3261]) that enable a network of trusted SIP servers to assert the service of end users or end systems. The use of these extensions is only applicable inside a ’trust domain’ as defined in "Short TermRequirements for Network Asserted Identity" (see RFC 3324 [RFC3324]). Nodes in such a trust domain are explicitly trusted by its users and end systems to publicly assert the service of each party, and thatthey have common and agreed-upon definitions of services andhomogeneous service offerings. The means by which the networkdetermines the service to assert is outside the scope of thisdocument (though it commonly entails some form of authentication).The mechanism for defining a trust domain is to provide a certain set of specifications known as ’Spec(T)’, and then specify compliance to that set of specifications. Spec(T) MUST specify behavior asdocumented in RFC 3324 [RFC3324].This document does NOT offer a general service model suitable forinter-domain use or use in the Internet at large. Its assumptionsabout the trust relationship between the user and the network may not apply in many applications. For example, these extensions do notaccommodate a model whereby end users can independently assert their service by use of the extensions defined here. End users asserttheir service by including the SIP and SDP parameters that correspond to the service they require. Furthermore, since the assertedservices are not cryptographically certified, they are subject toforgery, replay, and falsification in any architecture that does not meet the requirements of RFC 3324 [RFC3324].The asserted services also lack an indication of who specifically is asserting the service, and so it must be assumed that a member of the trust domain is asserting the service. Therefore, the information is only meaningful when securely received from a node known to be amember of the trust domain.Drage Informational [Page 5]Despite these limitations, there are sufficiently useful specialized deployments, that meet the assumptions described above and can accept the limitations that result, to warrant informational publication of this mechanism.3. ConventionsThe key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT","SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in BCP 14, RFC 2119[RFC2119].Throughout this document, requirements for or references to proxyservers or proxy behavior apply similarly to other intermediarieswithin a trust domain (for example, back-to-back user agents(B2BUAs)).The term trust domain in this document has the meaning as defined in RFC 3324 [RFC3324].4. Syntax of the Header FieldsThe following syntax specification uses the augmented Backus-NaurForm (BNF) as described in RFC 5234 [RFC5234].4.1. The P-Asserted-Service HeaderThe P-Asserted-Service header field is used among trusted SIPentities (typically intermediaries) to carry the service information of the user sending a SIP message.The P-Asserted-Service header field carries information that isderived service identification. While a declarative serviceidentification can assist in deriving the value transferred in thisheader field, this should be in the form of streamlining the correct derived service identification.PAssertedService = "P-Asserted-Service"HCOLON PAssertedService-valuePAssertedService-value = Service-ID *(COMMA Service-ID)See Section 4.4 for the definition of Service-ID in ABNF.Proxies can (and will) add and remove this header field.Drage Informational [Page 6]Table 1 adds the header fields defined in this document to Table 2 in SIP [RFC3261], Section 7.1 of the SIP-specific event notification[RFC3265], Tables 1 and 2 in the SIP INFO method [RFC2976], Tables 1 and 2 in the reliability of provisional responses in SIP [RFC3262],Tables 1 and 2 in the SIP UPDATE method [RFC3311], Tables 1 and 2 in the SIP extension for instant messaging [RFC3428], Table 1 in the SIP REFER method [RFC3515], and Tables 2 and 3 in the SIP PUBLISH method [RFC3903]:Header field where proxy ACK BYE CAN INV OPT REG SUB _______________________________________________________________ P-Asserted-Service R admr - - - o o - oHeader field NOT PRA INF UPD MSG REF PUB _______________________________________________________________ P-Asserted-Service - - - - o o oTable 1Syntactically, there may be multiple P-Asserted-Service header fields in a request. The semantics of multiple P-Asserted-Service headerfields appearing in the same request is not defined at this time.Implementations of this specification MUST provide only oneP-Asserted-Service header field value.4.2. The P-Preferred-Service HeaderThe P-Preferred-Service header field is used by a user agent sending the SIP request to provide a hint to a trusted proxy of the preferred service that the user wishes to be used for the P-Asserted-Servicefield value that the trusted element will insert.The P-Preferred-Service header field carries information that isdeclarative service identification. Such information should only be used to assist in deriving a derived service identification at therecipient entity.PPreferredService = "P-Preferred-Service"HCOLON PPreferredService-valuePPreferredService-value = Service-ID *(COMMA Service-ID)See Section 4.4 for the definition of Service-ID in ABNF.Table 2 adds the header fields defined in this document to Table 2 in SIP [RFC3261], Section 7.1 of the SIP-specific event notification[RFC3265], Tables 1 and 2 in the SIP INFO method [RFC2976], Tables 1 and 2 in Reliability of provisional responses in SIP [RFC3262],Drage Informational [Page 7]Tables 1 and 2 in the SIP UPDATE method [RFC3311], Tables 1 and 2 in the SIP extension for Instant Messaging [RFC3428], Table 1 in the SIP REFER method [RFC3515], and Tables 2 and 3 in the SIP PUBLISH method [RFC3903]:Header field where proxy ACK BYE CAN INV OPT REG SUB _______________________________________________________________ P-Preferred-Service R dr - - - o o - oHeader field NOT PRA INF UPD MSG REF PUB _______________________________________________________________ P-Preferred-Service - - - - o o oTable 2Syntactically, there may be multiple P-Preferred-Service headerfields in a request. The semantics of multiple P-Preferred-Serviceheader fields appearing in the same request is not defined at thistime. Implementations of this specification MUST only provide oneP-Preferred-Service header field value.4.3. Service and Application DefinitionService definitions and characteristics are outside the scope of this document. Other standards organizations, vendors, and operators may define their own services and register them.A hierarchical structure is defined consisting of service identifiers or application identifiers, and subservice identifiers.The service and subservice identifiers are as described in Section 1. The URN may also be used to identify a service or an applicationbetween end users for use within the context of RFC 3840 [RFC3840]and RFC 3841 [RFC3841].IANA maintains a registry of service identifier values that have been assigned. This registry has been created by the actions of Section8.2 of this document.subservice identifiers are not managed by IANA. It is theresponsibility of the organization that registered the service tomanage the subservices.4.4. Registration TemplateBelow, we include the registration template for the URN schemeaccording to RFC 3406 [RFC3406]. The URN scheme is defined as aninformal Namespace ID (NID).Drage Informational [Page 8]Namespace ID: urn-7Registration Information:Registration version: 1; registration date: 2009-03-22Declared registrant of the namespace: 3GPP Specifications Manager(3gppContact@) (+33 (0)492944200)Declaration of syntactic structure: The URN consists of ahierarchical service identifier or application identifier, with a sequence of labels separated by periods. The leftmost label isthe most significant one and is called ’top-level serviceidentifier’, while names to the right are called ’subservices’ or ’sub-applications’. The set of allowable characters is the sameas that for domain names (see RFC 1123 [RFC1123]) and a subset of the labels allowed in RFC 3958 [RFC3958]. Labels are case-insensitive and MUST be specified in all lowercase. For any given service identifier, labels can be removed right-to-left and theresulting URN is still valid, referring a more generic service,with the exception of the top-level service identifier andpossibly the first subservice or sub-application identifier.Labels cannot be removed beyond a defined basic service; forexample, the label w.x may define a service, but the label w mayonly define an assignment authority for assigning subsequentvalues and not define a service in its own right. In other words, if a service identifier ’w.x.y.z’ exists, the URNs ’w.x’ and’w.x.y’ are also valid service identifiers, but w may not be avalid service identifier if it merely defines who is responsiblefor defining x.Service-ID = "urn:urn-7:" urn-service-idurn-service-id = top-level *("." sub-service-id)top-level = let-dig [ *26let-dig ]sub-service-id = let-dig [ *let-dig ]let-dig = ALPHA / DIGIT / "-"While the naming convention above uses the term "service", all the constructs are equally applicable to identifying applicationswithin the UA.Relevant ancillary documentation: NoneIdentifier uniqueness considerations: A service identifieridentifies a service, and an application identifier an application indicated in the service or application registration (see IANAConsiderations (Section 8)). Uniqueness is guaranteed by the IANA registration.Drage Informational [Page 9]Identifier persistence considerations: The service or applicationidentifier for the same service or application is expected to bepersistent, although there naturally cannot be a guarantee that a particular service will continue to be available globally or atall times.Process of identifier assignment: The process of identifierassignment is described in the IANA Considerations (Section 8).Process for identifier resolution: There is no single globalresolution service for service identifiers or applicationidentifiers.Rules for lexical equivalence: ’service’ identifiers are comparedaccording to case-insensitive string equality.Conformance with URN syntax: The BNF in the ’Declaration ofsyntactic structure’ above constrains the syntax for this URNscheme.Validation mechanism: Validation determines whether a given stringis currently a validly assigned URN (see RFC 3406 [RFC3406]). Due to the distributed nature of usage and since not all services are available everywhere, validation in this sense is not possible.Scope: The scope for this URN can be local to a single domain, ormay be more widely used.5. Usage of the P-Preferred-Service and P-Asserted-Service HeaderFields5.1. Usage of the P-Preferred-Service and P-Asserted-Service HeaderFields in Requests5.1.1. Procedures at User Agent Clients (UAC)The UAC MAY insert a P-Preferred-Service in a request that creates a dialog, or a request outside of a dialog. This information canassist the proxies in identifying appropriate service capabilities to apply to the call. This information MUST NOT conflict with other SIP or SDP information included in the request. Furthermore, the SIP or SDP information needed to signal functionality of this service MUSTbe present. Thus, if a service requires a video component, then the SDP has to include the media line associated with that videocomponent; it cannot be assumed from the P-Preferred-Service headerfield value. Similarly, if the service requires particular SIPDrage Informational [Page 10]functionality for which a SIP extension and a Require header fieldvalue is defined, then the request has to include that SIP signaling as well as the P-Preferred-Service header field value.A UAC that is within the same trust domain as the proxy to which itsends a request (e.g., a media gateway or application server) MAYinsert a P-Asserted-Service header field in a request that creates a dialog, or a request outside of a dialog. This information MUST NOT conflict with other SIP or SDP information included in the request.Furthermore, the SIP or SDP information needed to signalfunctionality of this service MUST be present.5.1.2. Procedures at Intermediate ProxiesA proxy in a trust domain can receive a request from a node that ittrusts or a node that it does not trust. When a proxy receives arequest from a node it does not trust and it wishes to add aP-Asserted-Service header field, the proxy MUST identify the service appropriate to the capabilities (e.g., SDP) in the request, MAYauthenticate the originator of the request (in order to determinewhether the user is subscribed for that service). Where theoriginator of the request is authenticated, the proxy MUST use theidentity that results from this checking and authentication to insert a P-Asserted-Service header field into the request.When a proxy receives a request containing a P-Preferred-Serviceheader field, the Proxy MAY use the contents of that header field to assist in determining the service to be included in a P-Asserted-Service header field (for instance, to prioritize the order ofcomparison of filter criteria for potential services that the request could match). The proxy MUST NOT use the contents of theP-Preferred-Service header field to identify the service withoutfirst checking against the capabilities (e.g., SDP) contained in the request. If the proxy inserts a P-Asserted-Service header field inthe request, the proxy MUST remove the P-Preferred-Service headerfield before forwarding the request; otherwise, the Proxy SHOULDinclude the P-Preferred-Service header field when forwarding therequest.If the proxy receives a request from a node that it trusts, it canuse the information in the P-Asserted-Service header field, if any,as if it had authenticated the user itself.If there is no P-Asserted-Service header field present, or it is not possible to match the request to a specific service as identified by the service identifier, a proxy MAY add one containing it using itsown analysis of the information contained in the SIP request. If the proxy received the request from an element that it does not trust and Drage Informational [Page 11]there is a P-Asserted-Service header present, the proxy MUST replace that header field’s contents with a new analysis or remove thatheader field.The analysis performed to identify such service identifiers isoutside the scope of this document. However, it is perfectly validas a result of the analysis not to include any service identifier in the forwarded request, and thus not include a P-Asserted-Serviceheader field.If a proxy forwards a request to a node outside the proxy’s trustdomain, there MUST NOT be a P-Asserted-Service header field in theforwarded request.5.1.3. Procedures at User Agent ServersFor a User Agent Server (UAS) outside the trust domain, theP-Asserted-Service header is removed before it reaches this entity;therefore, there are no procedures for such a device.However, if a UAS receives a request from a previous element that it does not trust, it MUST NOT use the P-Asserted-Service header fieldin any way.If a UA is part of the trust domain from which it received a request containing a P-Asserted-Service header field, then it can use thevalue freely, but it MUST ensure that it does not forward theinformation to any element that is not part of the trust domain.5.2. Usage of the P-Preferred-Service and P-Asserted-Service HeaderFields in ResponsesThere is no usage of these header fields in responses.6. Examples of UsageIn this example, creates a P-Asserted-Serviceheader field from the user identity it discovered from SIP digestauthentication, the list of services appropriate to that user, andthe services that correspond to the SDP information included in therequest. Note that F1 and F2 are about identifying the user and donot directly form part of the capability provided in this document.It forwards this information to a trusted proxy that forwards it to a trusted gateway. Note that these examples consist of partial SIPmessages that illustrate only those header fields relevant to theauthenticated identity problem.Drage Informational [Page 12]* F1 -> INVITE sip:+14085551212@ SIP/2.0Via: SIP/2.0/TCP ;branch=z9hG4bK-123To: <sip:+14085551212@>From: "Anonymous" <sip:anonymous@anonymous.invalid>;tag=9802748Call-ID: 245780247857024504CSeq: 1 INVITEMax-Forwards: 70v=0o=- 2987933615 2987933615 IN IP6 5555::aaa:bbb:ccc:ddds=-c=IN IP6 5555::aaa:bbb:ccc:dddt=0 0m=audio 3456 RTP/AVPF 97 96b=AS:25.4a=curr:qos local sendrecva=curr:qos remote nonea=des:qos mandatory local sendrecva=des:qos mandatory remote sendrecva=sendrecva=rtpmap:97 AMRa=fmtp:97 mode-set=0,2,5,7; maxframes* F2 -> SIP/2.0 407 Proxy AuthorizationVia: SIP/2.0/TCP ;branch=z9hG4bK-123To: <sip:+14085551212@>;tag=123456From: "Anonymous" <sip:anonymous@anonymous.invalid>;tag=9802748Call-ID: 245780247857024504CSeq: 1 INVITEProxy-Authenticate: .... realm=""* F3 -> INVITE sip:+14085551212@ SIP/2.0Via: SIP/2.0/TCP ;branch=z9hG4bK-124To: <sip:+14085551212@>From: "Anonymous" <sip:anonymous@anonymous.invalid>;tag=9802748Call-ID: 245780247857024504CSeq: 2 INVITEMax-Forwards: 70Proxy-Authorization: realm="" user="fluffy"Drage Informational [Page 13]。

OpenSSLX509Certificate反序列化漏洞（CVE-2015-3825）成因分析作者：没羽官网：百度搜素“阿里聚安全”官方微博：阿里聚安全官方微信：阿里聚安全一、序序列化 (Serialization)，是将对象的状态信息转换为可以存储或传输的形式的过程。

在序列化期间，对象将其当前状态写入到临时或持久性存储区。

使用者可以通过从存储区中读取或反序列化对象的状态，重新创建该对象。

Android也有许多场景使用序列化进行数据传递，如App间/内的对象传递、Binder通信的数据传递等等，一般涉及跨进程、跨权限。

序列化/反序列也是程序/接口的一个输入，存储区的内容或序列是可被随机填充，如果使用时验证不完整，也会导致安全漏洞。

在Android系统中，可通过序列化/反序列化漏洞实现App拒绝服务、提升权限等攻击。

二、漏洞成因这个Android序列化漏洞(CVE-2015-3825)，影响Android4.3及Android5.1版本，也就是Jelly Bean、KitKat、棒棒糖和Android M预览版1，波及55%的Android设备。

可在受影响的设备上提权到system权限，也就意味着攻击者可以通过替换目标应用的apk接管受害者手机上的任意应用。

这个漏洞是由的IBM 安全团队Or Peles和Roee Hay在USENIX 2015大会上的议题《ONE CLASS TO RULE THEM ALL0-DAY DESERIALIZATION VULNERABILITIES IN ANDROID》[1]。

2.1 PoC构造Paper作者没放出Exploit也没放出PoC，根据这篇paper我们可以知道，漏洞出在OpenSSLX509Certificate（全包名路径为.conscrypt.OpenSSLX509Certificate）类，OpenSSLX509Certificate类满足：1）OpenSSLX509Certificate是可序列化的，因为他继承自可序列化的Certificate类；2）它有一个finalize()方法，并且有调用native的方法（libjavascrypto.so中），参数field mContext，long型（实际为指针类型）；3）OpenSSLX509Certificate也没有实现特定的反序列化方法（readObject和readResolve）；其中mContext就是要找的可被攻击控制的指针。

SIP出错原因码SIP（Session Initiation Protocol）出错原因码是指在SIP协议中，用于传递错误和异常情况的数字代码。

这些错误码帮助识别和解释SIP通信过程中出现的问题，便于调试和故障排除。

以下是一些常见的SIP出错原因码及其解释。

1xx系列：信息性响应- 100 Trying：请求已收到，仍在处理中。

- 180 Ringing：被叫正在响铃。

- 183 Session Progress：会话进程，表示正在接受来电。

2xx系列：成功响应-200OK：成功地处理了请求。

- 202 Accepted：已接受请求，但仍在处理中。

-230通过了RTP/RTCP警告检测过程，但解释原因结果为警告。

3xx系列：重定向响应- 300 Multiple Choices：呼叫有多个可能的目标，用户可以选择重播请求。

- 301 Moved Permanently：请求的URL已永久重定向至新位置。

- 302 Moved Temporarily：请求的URL已暂时重定向至新位置。

4xx系列：客户端错误响应- 400 Bad Request：请求格式有误。

- 401 Unauthorized：需要用户认证。

- 403 Forbidden：请求被服务器拒绝。

5xx系列：服务器错误响应- 500 Server Internal Error：服务器内部错误。

- 503 Service Unavailable：服务器当前无法提供服务。

- 504 Server Time-out：服务器处理请求超时。

更多的SIP出错原因码包括：- 600 Busy Everywhere：全线忙。

- 603 Declined：呼叫被拒绝或忽略。

- 604 Does Not Exist Anywhere：目标用户不存在。

- 606 Not Acceptable：媒体类型不可接受。

SIP出错原因码的选择取决于具体情况和问题类型。

unauthorized client with sessionid -回复题目：未经授权的客户端与sessionid引言：在当今信息高度互联的时代，网络安全问题日益突出。

未经授权的客户端访问和使用会话标识（session ID）是一种常见的网络安全威胁。

本文将详细介绍未经授权的客户端如何获取会话标识，以及如何逐步应对此类安全挑战，确保网络系统的安全性。

第一部分：未经授权的客户端如何获取会话标识在理解如何应对未经授权的客户端问题之前，首先需要了解未经授权客户端如何获取会话标识。

未经授权的客户端通常通过以下几种方式获取会话标识：1. XSS（跨站脚本）攻击：攻击者通过在合法网站注入恶意脚本，使用户在访问网站时执行该脚本，从而窃取会话标识。

此类攻击方式常见于社交媒体、在线银行等具有敏感信息的网站。

2. CSRF（跨站请求伪造）攻击：攻击者利用用户的权限，通过欺骗用户访问恶意网站或点击恶意链接等方式，使用户在不知情的情况下执行攻击者指定的操作。

通过这种方式，攻击者可以在用户的浏览器中获取会话标识，并用于未经授权的访问。

3. 会话劫持：攻击者通过网络监听、窃听会话等方式获取合法用户的会话标识。

这种方式常见于公共无线网络或黑客攻击者本地环境下。

第二部分：应对未经授权的客户端问题的措施在面对未经授权的客户端问题时，我们可以采取多种措施，以增加系统的安全性。

1. 输入验证和过滤：在输入验证方面，我们可以通过严格的输入验证和过滤来防止XSS攻击。

借助一系列的过滤器和验证规则，筛选掉恶意代码，从而预防恶意脚本的注入。

2. CSRF令牌：为了抵御CSRF攻击，可以通过在每个请求中添加随机生成的令牌来验证请求的合法性。

这样，在恶意网站欺骗用户点击链接时，由于缺乏合法令牌，攻击就无法成功。

3. 加密和安全传输：通过使用安全套接字层（SSL）协议，将会话标识通过加密通道传输。

这将减少会话被窃听或劫持的风险。

4. 安全授权和访问控制：通过引入强大的访问控制机制，例如使用角色基于访问控制（RBAC）或多因素认证，可以有效限制对敏感信息的访问。

naxsi waf 基本规则摘要：1.NAXSI WAF 简介2.NAXSI WAF 基本规则概述3.NAXSI WAF 基本规则详解4.总结正文：1.NAXSI WAF 简介AXSI（Nginx、Apache、X-Forwarded-For、SI）Web 应用防火墙是一款基于Nginx 的开源Web 应用防火墙，主要用于保护Web 应用免受各种攻击。

NAXSI WAF 通过在Nginx 服务器上配置一系列规则，对Web 应用的访问进行监控和过滤，从而提高Web 应用的安全性。

2.NAXSI WAF 基本规则概述AXSI WAF 的基本规则主要针对以下四个方面进行设置：- 允许/拒绝：允许或拒绝特定IP地址或地址段访问Web应用。

- 访问控制：根据用户代理、请求方法、请求路径等条件，允许或拒绝特定用户访问Web 应用。

- 错误页：自定义错误页，对访问出错时返回的页面进行设置。

- 静态文件：根据文件类型，允许或拒绝特定静态文件的访问。

3.NAXSI WAF 基本规则详解(1) 允许/拒绝在NAXSI WAF 中，可以通过配置允许或拒绝特定IP 地址或地址段访问Web 应用。

例如：```allow 192.168.1.1;deny 192.168.1.2;```(2) 访问控制AXSI WAF 可以根据用户代理、请求方法、请求路径等条件，允许或拒绝特定用户访问Web 应用。

例如：```allow User-Agent: *bot*;deny Method: POST;deny Path: /admin;```(3) 错误页在NAXSI WAF 中，可以自定义错误页，对访问出错时返回的页面进行设置。

例如：```error_page 403 /error/403.html;error_page 404 /error/404.html;```(4) 静态文件AXSI WAF 可以根据文件类型，允许或拒绝特定静态文件的访问。

网站系统安全防护体系建设方案目录一、需求说明 (3)二、网页防篡改解决方案 (5)2。

1 技术原理 (5)2.2 部署结构 (6)2.3 系统组成 (6)2.4 集群与允余部署 (8)2。

5 方案特点 (9)2。

5。

1 篡改检测和恢复 (9)2.5.2 自动发布和同步 (9)三、WEB应用防护解决方案 (11)3。

1 当前安全风险分析 (11)3.2 防护计划 (12)3。

2。

1 开发流程中加入安全性验证项目 (12)3。

2。

2 对网站程序的源代码进行弱点检测 (12)3。

2.3 导入网页应用程序漏洞列表作为审计项目 (13)3.2。

4 部署Web应用防火墙进行防御 (14)3.3 WEB应用防火墙功能 (15)3.3.1 集中管控功能 (15)3.3.2 防护功能 (15)3。

4 预期效益 (16)四、内容分发网络解决方案 (17)4.1 内容分发网络简介 (17)4。

2 CDN服务功能 (17)4.3 CDN服务特点 (18)五、负载均衡解决方案 (19)5.2 广域负载均衡 (20)5。

3 关键功能和特点 (21)六、应急响应服务体系 (23)6.1 事件分类与分级 (23)6.1。

1 事件分类 (23)6。

1.2 事件分级 (23)6.1.3 预警服务事件严重等级 (24)6。

2 应急响应服务体系 (25)一、需求说明针对Web应用防护安全需能实现以下功能：一、针对网站主页恶意篡改的监控,防护和快速恢复:（1）支持多种保护模式，防止静态和动态网页内容被非法篡改.（2）能够防止主页防护功能被恶意攻击者非法终止。

（3)具备核心内嵌技术，能实现高效快速实现大规模的网页攻击防护。

（4）支持实时检测和快速恢复功能。

（5）支持多服务器、多站点的主页防护（6）支持对常见的多种网页文件类型的保护。

（7）支持网页快照功能,根据需要即时提供快照页面,以满足客户端的访问。

二、对Web网站进行多层次检测分析与应用防护：（1）有效保护网站静动态网页以及后台DB信息，实现多方位攻击防护。

表3-2 响应消息?请求消息和响应消息都包括SIP头字段和SIP消息字段。

目? 录第3章SIP协议概述基本概念会话启动协议SIP（Session Initiation Protocol）是由IETF提出并主持研究的一个在IP网络上进行多媒体通信的应用层控制协议，它被用来创建、修改、和终结一个或多个参加者参加的会话进程。

这些会话包括Internet多媒体会议、Internet电话、远程教育以及远程医疗等。

即所有的因特网上交互式两方或多方多媒体通信活动，统称为多媒体会话。

参加会话的成员可以通过组播方式、单播联网方式或者两者结合的方式进行通信。

SIP协议是一个正在发展和不断研究中的协议。

一方面，它借鉴了其他Internet标准和协议的设计思想，在风格上遵循因特网一贯坚持的简练、开放、兼容和可扩展等原则，并充分注意到因特网开放而复杂的网络环境下的安全问题。

另一方面，它也充分考虑了对传统公共电话网的各种业务，包括IN业务和ISDN业务的支持。

利用带有会话描述的SIP邀请消息来创建会话，以使参加者能够通过SIP交互进行媒体类型协商。

它通过代理和重定向请求用户当前位置，以支持用户的移动性。

用户也可以登记它们的当前位置。

SIP协议独立于其他会议控制协议，它在设计上独立于下面的传输层协议，因此可以灵活方便地扩展其他附加功能。

SIP作为一个应用层的多媒体会话信令协议，可以被用来发起一个会话进程、在会话中邀请其他参加者加入会议，会话本身可以通过基于组播协议的会话通告协议（SAP）、电子邮件、网页通告、以及轻量级号薄访问协议（LDAP）等方式预先通告各个可能的参加者。

SIP协议支持别名映射、重定向服务、ISDN和IN业务。

它支持个人移动（personal mobility），即终端用户能够在任何地方、任何时间请求和获得已订购的任何电信业务。

总的来说，会话启动协议能够支持下列五种多媒体通信的信令功能：用户定位：确定参加通信的终端用户的位置；用户通信能力协商：确定通信的媒体类型和参数；用户意愿交互：确定被叫是否乐意参加某个通信；建立呼叫：包括向被叫“振铃”，确定主叫和被叫的呼叫参数；呼叫处理和控制：包括呼叫重定向、呼叫转移、终止呼叫等等。