--- 1/draft-ietf-dhc-isnsoption-03.txt 2006-02-04 23:04:21.000000000 +0100 +++ 2/draft-ietf-dhc-isnsoption-04.txt 2006-02-04 23:04:21.000000000 +0100 @@ -1,17 +1,17 @@ DHC Working Group Josh Tseng INTERNET DRAFT Kevin Gibbons - Expires: March 2003 Charles Monia + Expires: June 2003 Charles Monia Internet Draft - Document: Nishan Systems - Category: Standards Track September 2002 + Document: Nishan Systems + Category: Standards Track December 2002 DHCP Options for Internet Storage Name Service Status of this Memo This document is an Internet-Draft and is in full conformance with all provisions of Section 10 of [RFC2026]. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF), its areas, and its working groups. Note that @@ -27,49 +27,48 @@ The list of Internet-Draft Shadow Directories can be accessed at http://www.ietf.org/shadow.html. Comments Comments should be sent to the IPS mailing list (ips@ece.cmu.edu) or to the authors. Table of Contents - DHCP Option Number for iSNS Revision 3 September 2002 + DHCP Option Number for iSNS Revision 4 December 2002 Status of this Memo...................................................1 Comments..............................................................1 Abstract..............................................................3 Conventions used in this document.....................................3 1.Introduction.......................................................3 2.iSNS Option for DHCP...............................................4 2.1 iSNS Functions Field.............................................5 2.2 Discovery Domain Access Field....................................6 2.3 Administrative Flags Field.......................................7 2.4 iSNS Server Security Bitmap......................................9 3.Security Considerations...........................................10 4.Normative References..............................................10 - 5.Non-Normative References..........................................10 + 5.Non-Normative References..........................................11 6.Author's Addresses................................................11 Full Copyright Statement.............................................12 - DHCP Option Number for iSNS Revision 3 September 2002 + DHCP Option Number for iSNS Revision 4 December 2002 Abstract This document describes the DHCP option to allow iSNS clients using DHCP to automatically discover the location of the iSNS server. iSNS provides discovery and management capabilities for iSCSI and Fibre - Channel (FCP) storage devices in an enterprise-scale IP storage - network. iSNS provides intelligent storage management services - comparable to those found in Fibre Channel networks, allowing a - commodity IP network to function in a similar capacity as a storage - area network. + Channel storage devices in an enterprise-scale IP storage network. + iSNS provides intelligent storage management services comparable to + those found in Fibre Channel networks, allowing a commodity IP + network to function in a similar capacity as a storage area network. Conventions used in this document iSNS refers to the framework consisting of the storage network model and associated services. The 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 [RFC2119]. @@ -99,25 +98,25 @@ The Dynamic Host Configuration Protocol provides a framework for passing configuration information to hosts. Its usefulness extends to hosts and devices using the iSCSI and iFCP protocols to connect to block level storage assets over a TCP/IP network. The iSNS Protocol provides a framework for automated discovery, management, and configuration of iSCSI and iFCP devices on a TCP/IP network. It provides functionality similar to that found on Fibre Channel networks, except that iSNS works within the context of an IP - DHCP Option Number for iSNS Revision 3 September 2002 - network. iSNS thereby provides the requisite storage intelligence to IP networks that are standard on existing Fibre Channel networks. + DHCP Option Number for iSNS Revision 4 December 2002 + Existing DHCP option numbers are not plausible due to the following reasons: a) iSNS functionality is distinctly different from other protocols using existing DHCP option numbers. Specifically, iSNS provides a significant superset of capabilities compared to typical name resolution protocols such as DNS. It is designed to support client devices that allow themselves to be configured and managed from a central iSNS server @@ -155,26 +154,26 @@ Figure 1 -- iSNS Server Option The iSNS Option specifies a list of IP addresses used by iSNS servers. The option contains the following parameters: Length: the number of bytes that follow the Length field. The minimum value for the Length field is 6 in order to account for the iSNS Functions, Discovery Domain Access, and Administrative Flags fields. - DHCP Option Number for iSNS Revision 3 September 2002 - iSNS Functions: A bitmapped field defining the functions supported by the iSNS servers. The format of this field is described in section 2.1. + DHCP Option Number for iSNS Revision 4 December 2002 + Discovery Domain Access: A bit field indicating the types of iSNS clients that are allowed to modify Discovery Domains. The field contents are described in section 2.2. Administrative Flags field: Contains the administrative settings for the iSNS servers discovered through the DHCP query. The contents of this field are described in section 2.3. iSNS Server Security Bitmap: Contains the iSNS server security settings specified in section 2.4. @@ -201,35 +200,36 @@ significant as providing IKE/IPSec security policies and certificates for the use of iSCSI and iFCP devices. The format of the iSNS Role bit field is shown in Figure 2: 1 2 3 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +--+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |Vendor-Specific |RESERVED |S|A|E| +--+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 2 -- iSNS Functions - DHCP Option Number for iSNS Revision 3 September 2002 Bit field Significance --------- ------------ 31 Function Fields Enabled 30 DD-Based Authorization 29 Security policy distribution 28 - 24 Reserved 23 - 16 Vendor-specific Enabled: This bit specifies the validity of the remaining iSNS Function fields. If set to one, then the contents of all other iSNS Function fields are valid. If set to zero, then the contents of all other iSNS + DHCP Option Number for iSNS Revision 4 December 2002 + Function fields MUST be ignored. DD-based Indicates whether or not devices in a Authorization: common Discovery Domain (DD) are implicitly authorized to access one another. Although Discovery Domains control the scope of device discovery, they do not necessarily indicate whether or not a domain member is authorized to access discovered devices. If this bit is set to one, then devices in @@ -252,40 +252,39 @@ If set to zero, then the iSNS client must obtain its security policy configuration by other means. Vendor- These bits are used to indicate the vendor- Specific: specific capabilities supported by the indicated iSNS server. 2.2 Discovery Domain Access Field - The format of the DD Access bit field is shown in Figure 3: - - DHCP Option Number for iSNS Revision 3 September 2002 + The format of the DD Access bit field is shown in + Figure 3: - 0 1 2 3 4 5 6 7 - +---+---+---+---+---+---+---+---+ - | R | R | if| tf| is| ts| C | E | - +---+---+---+---+---+---+---+---+ + 0 1 2 3 4 5 6 ... 15 + +---+---+---+---+---+---+---+---+---+ + | if| tf| is| ts| C | E | Reserved | + +---+---+---+---+---+---+---+---+---+ Figure 3 -- Discovery Domain Access + DHCP Option Number for iSNS Revision 4 December 2002 Bit field Significance --------- ------------ - 7 Enabled - 6 Control Node - 5 iSCSI Target - 4 iSCSI Initiator - 3 iFCP Target Port - 2 iFCP Initiator Port - 1 RESERVED - 0 RESERVED + 0 iFCP Initiator Port + 1 iFCP Target Port + 2 iSCSI Initiator + 3 iSCSI Target + 4 Control Node + 5 Enabled + 6 ... 15 Reserved Enabled: This bit specifies the validity of the remaining DD Access bit fields. If this bit is set to one, then the contents of the remainder of the DD Access field are valid. If this bit is set to zero, then the contents of the remainder of this field MUST be ignored. Control Node: Specifies whether the iSNS server allows @@ -305,54 +304,54 @@ one, then modification by the specified client type is allowed. If set to zero, then modification by the specified client type is not allowed. (A node may implement multiple node types.) 2.3 Administrative Flags Field - The format of the Administrative Flags bit field is shown in Figure - 4: + The format of the Administrative Flags bit field is shown in + Figure 4: - DHCP Option Number for iSNS Revision 3 September 2002 + DHCP Option Number for iSNS Revision 4 December 2002 1 2 3 - 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 - +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | RESERVED |D|M|H|E| - +---+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Figure 4 -- Administrative Flags Bit Field Significance --------- ------------ 31 Enabled 30 Heartbeat 29 Management SCNs - 28 Default Discovrery Domain - 27 - 8 RESERVED + 28 Default Discovery Domain + 27 - 16 RESERVED Enabled: Specifies the validity of the remainder of the Administrative Flags field. If set to one, then the contents of the remaining Administrative Flags are valid. If set to zero, then the remaining contents MUST be ignored, indicating that iSNS administrative settings are obtained through means other than DHCP. Heartbeat: Indicates whether the first IP address - is the multicast address from which the - iSNS heartbeat message originates. If - set to one, then a1-a4 contains the + is the multicast address to which the + iSNS heartbeat message is sent. If set + to one, then a1-a4 contains the heartbeat multicast address and b1-b4 contains the IP address of the primary iSNS server, followed by the IP address(es) of any backup servers. If set to zero, then a1-a4 contains the IP address of the primary iSNS server, followed by the IP address(es) of any backup servers. Management SCNs: Indicates whether control nodes are @@ -363,21 +362,21 @@ scope is the entire iSNS database. If set to one, then control nodes are authorized to register to receive Management SCN's. If set to zero, then control nodes are not authorized to receive Management SCN's (although they may receive normal SCN's). Default Discovery Indicates whether a newly registered device that is not explicitly placed - DHCP Option Number for iSNS Revision 3 September 2002 + DHCP Option Number for iSNS Revision 4 December 2002 Domain: into a Discovery Domain (DD) and Discovery Domain Set (DDS) should be automatically placed into a default DD and DDS. If set to one, then a default DD shall contain all devices in the iSNS database that have not been explicitly placed into a DD by an iSNS client. If set to zero, then devices not explicitly placed into a DD are not members of any @@ -400,21 +399,21 @@ Bit Field Significance --------- ---------------- 31 Enabled 30 IKE/IPSec 29 Main Mode 28 Aggressive Mode 27 PFS 26 Transport Mode 25 Tunnel Mode 24 -- 0 Reserved - DHCP Option Number for iSNS Revision 3 September 2002 + DHCP Option Number for iSNS Revision 4 December 2002 Enabled This bit specifies the validity of the remainder of the iSNS server security bitmap. If set to one, then the contents of the remainder of the field are valid. If set to zero, then the contents of the rest of the field are undefined and MUST be ignored. IKE/IPSec 1 = IKE/IPSec enabled; 0 = IKE/IPSec @@ -434,38 +433,46 @@ Tunnel Mode 1 = Tunnel mode preferred; 0 = No preference. 3. Security Considerations DHCP currently provides no authentication or security mechanisms. Potential exposures to attack are discussed in section 7 of the DHCP protocol specification [DHCP]. iSNS security considerations are discussed in [iSNS] and [SEC-IPS]. + With regard to security considerations specific to the use of this + DHCP option to discover the location of the iSNS server, exposure to + a "man-in-the-middle" attack by an hostile entity modifying or + replacing the original iSNS option message should be considered a + potential security exposure. To prevent an attacker from weakening + the required security and potentially tricking the iSNS client into + connecting into rogue iSNS servers, reliance on local security + policy configuration is an appropriate countermeasure. 4. Normative References [DHCP] Droms, R., "Dynamic Host Configuration Protocol", RFC 2131, Bucknell University, March 1997. [RFC2026] Bradner, S., "The Internet Standards Process -- Revision 3", BCP 9, RFC 2026, October 1996 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997 + DHCP Option Number for iSNS Revision 4 December 2002 5. Non-Normative References [iFCP] Monia, C., et al., "iFCP - A Protocol for Internet Fibre Channel Storage Networking", Internet draft (work in progress), draft-ietf-ips-ifcp-13.txt, May 2002 - DHCP Option Number for iSNS Revision 3 September 2002 [iSCSI] Satran, J., et al., "iSCSI", Internet draft (work in progress), draft-ietf-ips-iSCSI-15.txt, August 2002 [iSNS] Tseng, J. et al., "iSNS - Internet Storage Name Service", Internet draft (work in progress), draft-ietf- ips-isns-12.txt, August 2002 [SEC-IPS] Aboba, B., et al., "Securing IP Block Storage Protocols", draft-ietf-ips-security-14.txt, June 2002 @@ -478,21 +485,21 @@ Nishan Systems 3850 North First Street San Jose, CA 95134-1702 Phone: (408) 519-3700 Email: cmonia@nishansystems.com jtseng@nishansystems.com kgibbons@nishansystems.com Full Copyright Statement - "Copyright (C) The Internet Society September 2002. All Rights + "Copyright (C) The Internet Society December 2002. All Rights Reserved. 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