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Please use uppercase 'NOT' together with RFC 2119 keywords (if that is what you mean). Found 'MUST not' in this paragraph: The I2RS Protocol depends upon a secure transport layer for peer authentication, data integrity, confidentiality, and replay protection. The optional insecure transport can only be used restricted set of publically data available (events or information) or a select set of legacy data. Data passed over the insecure transport channel MUST not contain any data which identifies a person or any "write" transactions. -- The document date (September 15, 2016) is 2751 days in the past. Is this intentional? 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Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 I2RS working group S. Hares 3 Internet-Draft Huawei 4 Intended status: Informational D. Migault 5 Expires: March 19, 2017 J. Halpern 6 Ericsson 7 September 15, 2016 9 I2RS Security Related Requirements 10 draft-ietf-i2rs-protocol-security-requirements-11 12 Abstract 14 This presents security-related requirements for the I2RS protocol 15 which provides a new interface to the routing system described in the 16 I2RS architecture document (RFC7921). The I2RS protocol is a re-use 17 protocol implemented by re-using portions of existing IETF protocols 18 and adding new features to these protocols. The I2RS protocol re- 19 uses security features of a secure transport (E.g. TLS, SSH, DTLS) 20 such as encryption, message integrity, mutual peer authentication, 21 and replay protection. The new security features I2RS adds are: a 22 priority mechanism to handle multi-headed write transactions, an 23 opaque secondary identifier which identifies an application using the 24 I2RS client, and an extremely constrained read-only non-secure 25 transport. This document provides the detailed requirements for 26 these security features. 28 Status of This Memo 30 This Internet-Draft is submitted in full conformance with the 31 provisions of BCP 78 and BCP 79. 33 Internet-Drafts are working documents of the Internet Engineering 34 Task Force (IETF). Note that other groups may also distribute 35 working documents as Internet-Drafts. The list of current Internet- 36 Drafts is at http://datatracker.ietf.org/drafts/current/. 38 Internet-Drafts are draft documents valid for a maximum of six months 39 and may be updated, replaced, or obsoleted by other documents at any 40 time. It is inappropriate to use Internet-Drafts as reference 41 material or to cite them other than as "work in progress." 43 This Internet-Draft will expire on March 19, 2017. 45 Copyright Notice 47 Copyright (c) 2016 IETF Trust and the persons identified as the 48 document authors. All rights reserved. 50 This document is subject to BCP 78 and the IETF Trust's Legal 51 Provisions Relating to IETF Documents 52 (http://trustee.ietf.org/license-info) in effect on the date of 53 publication of this document. Please review these documents 54 carefully, as they describe your rights and restrictions with respect 55 to this document. Code Components extracted from this document must 56 include Simplified BSD License text as described in Section 4.e of 57 the Trust Legal Provisions and are provided without warranty as 58 described in the Simplified BSD License. 60 Table of Contents 62 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3 63 2. Definitions . . . . . . . . . . . . . . . . . . . . . . . . . 4 64 2.1. Requirements Language . . . . . . . . . . . . . . . . . . 4 65 2.2. Security Definitions . . . . . . . . . . . . . . . . . . 5 66 2.3. I2RS Specific Definitions . . . . . . . . . . . . . . . . 5 67 3. Security Features and Protocols: Re-used and New . . . . . . 7 68 3.1. Security Protocols Re-Used by the I2RS Protocol . . . . . 7 69 3.2. New Features Related to Security . . . . . . . . . . . . 8 70 3.3. I2RS Protocol Security Requirements vs. IETF Management 71 Protocols . . . . . . . . . . . . . . . . . . . . . . . . 9 72 4. Security-Related Requirements . . . . . . . . . . . . . . . . 10 73 4.1. I2RS Peers(agent and client) Identity Authentication . . 11 74 4.2. Identity Validation Before Role-Based Message Actions . . 12 75 4.3. Peer Identity, Priority, and Client Redundancy . . . . . 12 76 4.4. Multi-Channel Transport: Secure Transport and Insecure 77 Transport . . . . . . . . . . . . . . . . . . . . . . . . 14 78 4.5. Management Protocol Security . . . . . . . . . . . . . . 16 79 4.6. Role-Based Data Model Security . . . . . . . . . . . . . 17 80 4.7. Security of the environment . . . . . . . . . . . . . . . 18 81 5. Security Considerations . . . . . . . . . . . . . . . . . . . 18 82 6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 18 83 7. Acknowledgement . . . . . . . . . . . . . . . . . . . . . . . 18 84 8. References . . . . . . . . . . . . . . . . . . . . . . . . . 18 85 8.1. Normative References . . . . . . . . . . . . . . . . . . 18 86 8.2. Informative References . . . . . . . . . . . . . . . . . 19 87 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 21 89 1. Introduction 91 The Interface to the Routing System (I2RS) provides read and write 92 access to information and state within the routing process. An I2RS 93 client interacts with one or more I2RS agents to collect information 94 from network routing systems. [RFC7921] describes the architecture 95 of this interface, and this documents assumes the reader is familiar 96 with this architecture and its definitions. Section 2 highlights 97 some of the references the reader is required to be familiar with. 99 The I2RS interface is instantiated by the I2RS protocol connecting an 100 I2RS client and an I2RS agent associated with a routing system. The 101 I2RS protocol is a re-use protocol implemented by re-using portions 102 of existing IETF protocols, and adding new features to these 103 protocols. As a re-use protocol, it can be considered a higher-level 104 protocol since it can be instantiated in multiple management 105 protocols (e.g. NETCONF [RFC6241] or RESTCONF 106 [I-D.ietf-netconf-restconf]) operating over a secure transport. The 107 security for the I2RS protocol comes from the managmenet protocols 108 operating over a a secure transport which carries traffic over 109 multiple links. 111 This document is part of the requirements for I2RS protocol which 112 also include: 114 o I2RS architecture [RFC7921], 116 o I2RS ephemeral state requirements [I-D.ietf-i2rs-ephemeral-state], 118 o publication/subscription requirements [RFC7922], and 120 o traceability [RFC7923]. 122 Since the I2RS "higher-level" protocol changes the interface to the 123 routing systems, it is important that implementers understand the new 124 security requirements for the environment the I2RS protocol operates 125 in. These secuirty requirements for the I2RS environment are 126 specified in [I-D.ietf-i2rs-security-environment-reqs], and the 127 summary of the I2RS protocol security environment found in the I2RS 128 Architecture [RFC7920]. 130 I2RS reuses the secure transport protocols (TLS, SSH, DTLS) which 131 support encryption, message integrity, peer authentication, and key 132 distribution protocols. Optionally, implementers may utilize AAA 133 protocols (Radius over TLS or Diameter over TLS) to securely 134 distribute identity information. 136 Section 3 provides an overview of security features and protocols 137 being re-used (section 3.1) and the new security features being 138 required (section 3.2). Section 3 also explores how existing and new 139 security features and protocols would be paired with existing IETF 140 management protocols (section 3.3). 142 The new features I2RS extends to these protocols are a priority 143 mechanism to handle multi-headed reads, an opaque secondary 144 identifier to allow traceability of an application utilizing a 145 specific I2RS client to communicate with an I2RS agent, and insecure 146 transport constrained to be utilized only for read-only data which 147 publically available data (e.g. public BGP Events, public telemetry 148 information, web service available) and some legacy data. 150 Section 4 provides the I2RS protocol security requirements by the 151 following security features: 153 o peer identity authentication (section 4.1), 155 o peer identity validation before role-based message actions 156 (section 4.2) 158 o peer identity and client redundancy (section 4.3), 160 o multi-channel transport requirements: Secure transport and 161 insecure Transport (section 4.4), 163 o management protocol security requirements (section 4.5), 165 o role-based security (section 4.6), 167 o security environment (section 4.7) 169 Protocols designed to be I2RS higher-layer protocols need to fulfill 170 these security requirements. 172 2. Definitions 174 2.1. Requirements Language 176 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 177 "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this 178 document are to be interpreted as described in RFC 2119 [RFC2119]. 180 2.2. Security Definitions 182 This document utilizes the definitions found in the following 183 documents: [RFC4949] and [RFC7921] 185 Specifically, this document utilizes the following definitions from 186 [RFC4949]: 188 o access control, 190 o authentication, 192 o data confidentiality, 194 o data integrity, 196 o data privacy, 198 o identity, 200 o identifier, 202 o mutual authentication, 204 o role, 206 o role-based access control, 208 o security audit trail, and 210 o trust. 212 [RFC7922] describes traceability for I2RS interface and the I2RS 213 protocol. Traceability is not equivalent to a security audit trail 214 or simple logging of information. A security audit trail may utilize 215 traceability information. 217 This document also requires that the user is familiar with the 218 pervasive security requirements in [RFC7258]. 220 2.3. I2RS Specific Definitions 222 The document utilizes the following concepts from the I2RS 223 architecture: [RFC7921]: 225 o I2RS client, I2RS agent, and I2RS protocol (section 2), 227 o I2RS higher-layer protocol (section 7.2) 228 o scope: read scope, notification scope, and write scope (section 229 2), 231 o identity and scope of the identity (section 2), 233 o roles or security rules (section 2), 235 o identity and scope, and secondary identity (section 2), 237 o routing system/subsytem (section 2), 239 o I2RS assumed security environment (section 4), 241 o I2RS identity and authorization (section 4.1), 243 o I2RS authorization, scope of Authorization in I2RS client and 244 agent (section 4.2), 246 o client redundancy with a single client identity (section 4.3), 248 o restrictions on I2RS in personal devices (section 4.4), 250 o communication channels and I2RS high-layer protocol (section 7.2), 252 o active communication versus connectivity (section 7.5), 254 o multi-headed control (section 7.8), and 256 o transaction, message, multi-message atomicity (section 7.9). 258 This document assumes the reader is familar with these terms. 260 This document discusses the security of the multiple I2RS 261 communication channels which operate over the higher-layer I2RS 262 protocol. The higher-layer I2RS protocol combines a secure transport 263 and I2RS contextual information, and re-uses IETF protocols and data 264 models to create the secure transport and the I2RS data-model driven 265 contextual information. To describe how the I2RS high-layer protocol 266 combines other protocols into the I2RS higher-layer protocol, the 267 following terms are used: 269 I2RS component protocols 271 Protocols which are re-used and combined to create the I2RS 272 protocol. 274 I2RS secure-transport component protocols 275 The I2RS secure transport protocols that support the I2RS higher- 276 layer protocol. 278 I2RS management component protocols 280 The I2RS management protocol which provide the management 281 information context. 283 I2RS AAA component protocols 285 The I2RS AAA protocols supporting the I2RS higher-layer protocol. 287 The I2RS higher-layer protocol requires implementation of a I2RS 288 secure-transport component protocol and the I2RS management component 289 protocol. The I2RS AAA component protocol is optional. 291 3. Security Features and Protocols: Re-used and New 293 3.1. Security Protocols Re-Used by the I2RS Protocol 295 I2RS also requires a secure transport protocol and key distribution 296 protocols. The secure transport features required by I2RS are peer 297 authentication, confidentiality, data integrity, and replay 298 protection for I2RS messages. According to 299 [I-D.ietf-taps-transports], the secure transport protocols which 300 support peer authentication, confidentiality, data integrity, and 301 replay protection are the following: 303 1. TLS [RFC5246] over TCP or SCTP, 305 2. DTLS over UDP with replay detection and anti-DoS stateless cookie 306 mechanism required for the I2RS protocol, and the I2RS protocol 307 allow DTLS options of record size negotiation and and conveyance 308 of "don't" fragment bits to be optional in deployments. 310 3. HTTP over TLS (over TCP or SCTP), and 312 4. HTTP over DTLS (with the requirements and optional features 313 specified above in item 2). 315 The following protocols will need to be extended to provide 316 confidentiality, data integrity, peer authentication, and key 317 distribution protocols: SSH, SCTP, or the ForCES TML layer over SCTP. 319 The specific type of key management protocols an I2RS secure 320 transport uses depends on the transport. Key management protocols 321 utilized for the I2RS protocols SHOULD support automatic rotation. 323 An I2RS implementer may use AAA protocols over secure transport to 324 distribute the identities for I2RS client and I2RS agent and role 325 authorization information. Two AAA protocols are: Diameter [RFC6733] 326 and Radius [RFC2865]. To provide the best security I2RS peer 327 identities, the AAA protocols MUST be run over a secure transport 328 (Diameter over secure transport (TLS over TCP) [RFC6733]), Radius 329 over a secure transport (TLS) [RFC6614]). 331 3.2. New Features Related to Security 333 The new features are priority, an opaque secondary identifier, and an 334 insecure protocol for read-only data constrained to specific standard 335 usages. The I2RS protocol allows multi-headed control by several 336 I2RS clients. This multi-headed control is based on the assumption 337 that the operator deploying the I2RS clients, I2RS agents, and the 338 I2rs protocol will coordinate the read, write, and notification scope 339 so the I2RS clients will not contend for the same write scope. 340 However, just in case there is an unforseen overlap of I2RS clients 341 attempting to write a particular piece of data, the I2RS architecture 342 [RFC7921] provides the concept of each I2RS client having a priority. 343 The I2RS client with the highest priority will have its write 344 succeed. This document specifies requirements for this new concept 345 of priority. 347 The opaque secondary identifier identifies an application which is 348 using the I2RS client to I2RS agent communication to manage the 349 routing system. The secondary identifier is opaque to the I2RS 350 protocol. In order to protect personal privacy, the secondary 351 identifier should not contain personal identifiable information. 353 The last new security feature is the ability to allow non- 354 confidential data to be transfered over a non-secure transport. It 355 is expected that most I2RS data models will describe information that 356 will be transferred with confidentiality. Therefore, any model which 357 transfers data over a non-secure transport is marked. The use of a 358 non-secure transport is optional, and an implementer SHOULD create 359 knobs that allow data marked as non-confidential to be sent over a 360 secure transport. 362 Non-confidential data can only be read or notification scope 363 transmission of events. Non-confidential data cannot be write scope 364 or notification scope configuration. An example of non-confidential 365 data is the telemetry information that is publically known (e.g. BGP 366 route-views data or web site status data) or some legacy data (e.g. 367 interface) which cannot be transported in secure transport. The IETF 368 I2RS Data models MUST indicate in the data model the specific data 369 which is non-confidential. 371 Most I2RS data models will expect that the information described in 372 the model will be transferred with confidentiality. Therefore, it is 374 3.3. I2RS Protocol Security Requirements vs. IETF Management Protocols 376 Table 1 below provides a partial list of the candidate management 377 protocols and the secure transports each one of the support. One 378 column in the table indicates the transport protocol will need I2RS 379 security extensions. 381 Mangement 382 Protocol Transport Protocol I2RS Extensions 383 ========= ===================== ================= 384 NETCONF TLS over TCP (*1) None required (*2) 386 RESTCONF HTTP over TLS with None required (*2) 387 X.509v3 certificates, 388 certificate validation, 389 mutual authentication: 390 1) authenticated 391 server identity, 392 2) authenticated 393 client identity 394 (*1) 396 FORCES TML overs SCTP Needs extension to 397 (*1) TML to run TML 398 over TLS over SCTP, 399 or DTLS described 400 above. The 401 IPSEC mechanism is 402 not sufficient for 403 I2RS traveling over 404 multiple hops 405 (router + link) 406 (*2) 408 IPFIX SCTP, TCP, UDP Needs to extension 409 TLS or DTLS for to support TLS or 410 secure client (*1) DTLS with options 411 described above. (*2) 413 *1 - Key management protocols 414 MUST support appropriate key rotation. 416 *2 - Identity and Role authorization distributed 417 by Diameter or Radius MUST use Diameter over TLS 418 or Radius over TLS. 420 4. Security-Related Requirements 422 This section discusses security requirements based on the following 423 security functions: 425 o peer identity authentication (section 4.1), 426 o Peer Identity validation before Role-based Message Actions 427 (section 4.2) 429 o peer identity and client redundancy (section 4.3), 431 o multi-channel transport requirements: Secure transport and 432 insecure Transport (section 4.4), 434 o management protocol security requirements (section 4.5), 436 o role-based security (section 4.6), 438 o security environment (section 4.7) 440 The I2RS Protocol depends upon a secure transport layer for peer 441 authentication, data integrity, confidentiality, and replay 442 protection. The optional insecure transport can only be used 443 restricted set of publically data available (events or information) 444 or a select set of legacy data. Data passed over the insecure 445 transport channel MUST not contain any data which identifies a person 446 or any "write" transactions. 448 4.1. I2RS Peers(agent and client) Identity Authentication 450 The following requirements specify the security requirements for Peer 451 Identity Authentication for the I2RS protocol: 453 o SEC-REQ-01: All I2RS clients and I2RS agents MUST have an 454 identity, and at least one unique identifier that uniquely 455 identifies each party in the I2RS protocol context. 457 o SEC-REQ-02: The I2RS protocol MUST utilize these identifiers for 458 mutual identification of the I2RS client and I2RS agent. 460 o SEC-REQ-03: Identifier distribution and the loading of these 461 identifiers into I2RS agent and I2RS client SHOULD occur outside 462 the I2RS protocol prior to the I2RS protocol establishing a 463 connection between I2RS client and I2RS agent. AAA protocols MAY 464 be used to distribute these identifiers, but other mechanism can 465 be used. 467 Explanation: 469 These requirements specify the requirements for I2RS peer (I2RS agent 470 and I2RS client) authentication. A secure transport (E.g. TLS) will 471 authenticate based on these identities. The AAA protocol 472 distributing I2RS identity information SHOULD transport its 473 information over a secure transport. 475 4.2. Identity Validation Before Role-Based Message Actions 477 The requirements for I2RS clients with Secure Connections are the 478 following: 480 SEC-REQ-04: An I2RS agent receiving a request from an I2RS client 481 MUST confirm that the I2RS client has a valid identity. 483 SEC-REQ-05: An I2RS client receiving an I2RS message over a secure 484 transport MUST confirm that the I2RS agent has a valid identifier. 486 SEC-REQ-06: An I2RS agent receiving an I2RS message over an 487 insecure transport MUST confirm that the content is suitable for 488 transfer over such a transport. 490 Explanation: 492 Each I2RS client has a scope based on its identity and the security 493 roles (read, write, or events) associated with that identity, and 494 that scope must be considered in processing an I2RS messages sent on 495 a communication channel. An I2RS communication channel may utilize 496 multiple transport sessions, or establish a transport session and 497 then close the transport session. Therefore, it is important that 498 the I2RS peers are operating utilizing valid peer identities when a 499 message is processed rather than checking if a transport session 500 exists. 502 4.3. Peer Identity, Priority, and Client Redundancy 504 Requirements: 506 SEC-REQ-07: Each I2RS Identifier MUST be associated with just one 507 priority. 509 SEC-REQ-08: Each Identifier is associated with one secondary 510 identifier during a particular I2RS transaction (e.g. read/write 511 sequence), but the secondary identifier may vary during the time a 512 connection between the I2RS client and I2RS agent is active. 514 Explanation: 516 The I2RS architecture also allows multiple I2RS clients with unique 517 identities to connect to an I2RS agent (section 7.8). The I2RS 518 deployment using multiple clients SHOULD coordinate this multi-headed 519 control of I2RS agents by I2RS clients so no conflict occurs in the 520 write scope. However, in the case of conflict on a write scope 521 variable, the error resolution mechanisms defined by the I2RS 522 architecture multi-headed control ([RFC7921], section 7.8) allow the 523 I2RS agent to deterministically choose one I2RS client. The I2RS 524 client with highest priority is given permission to write the 525 variable, and the second client receives an error message. 527 A single I2RS client may be associated with multiple applications 528 with different tasks (e.g. weekly configurations or emergency 529 configurations). The secondary identity is an opaque value that the 530 I2RS client passes to the I2RS agent so that this opaque value can be 531 placed in the tracing file or event stream to identify the 532 application using the I2RS client to I2RS agent communication. 534 One example of the use of the secondary identity is the situation 535 where an operator of a network has two applications that use an I2RS 536 client. The first application is a weekly configuration application 537 that uses the I2RS protocol to change configurations. The second 538 application is an application that allows operators to makes 539 emergency changes to routers in the network. Both of these 540 applications use the same I2RS client to write to an I2RS agent. In 541 order for traceability to determine which application (weekly 542 configuration or emergency) wrote some configuration changes to a 543 router, the I2RS client sends a different opaque value for each of 544 the applications. The weekly configuration secondary opaque value 545 could be "xzzy-splot" and the emergency secondary opaque value could 546 be "splish-splash". 548 A second example is if the I2RS client is used for monitoring of 549 critical infrastructure. The operator of a network using the I2RS 550 client may desire I2RS client redundancy where the monitoring 551 application wth the I2RS client is deployed on two different boxes 552 with the same I2RS client identity (see [RFC7921] section 4.3) These 553 two monitoring applications pass to the I2RS client whether the 554 application is the primary or back up application, and the I2RS 555 client passes this information in the I2RS secondary identitifier as 556 the figure below shows. The primary applications secondary 557 identifier is "primary-monitoring", and the backup application 558 secondary identifier is "backup-monitoring". The I2RS tracing 559 information will include the secondary identifier information along 560 with the transport information in the tracing file in the agent. 562 Example 2: Primary and Backup Application for Monitoring 563 Identification sent to agent 565 Application A--I2RS client--Secure transport(#1) 566 [I2RS identity 1, secondary identifier: "primary-monitoring"]--> 568 Application B--I2RS client--Secure transport(#2) 569 [I2RS identity 1, secondary identifier: "backup-monitoring"]--> 571 Figure 1 573 4.4. Multi-Channel Transport: Secure Transport and Insecure Transport 575 Requirements: 577 SEC-REQ-09: The I2RS protocol MUST be able to transfer data over a 578 secure transport and optionally MAY be able to transfer data over 579 a non-secure transport. The default transport is a secure 580 transport, and this means it is mandatory to implement (MTI) in 581 all I2RS agents, and in any I2RS client which: a) performs a Write 582 scope transaction which is sent to the I2RS agent or b): 583 configures an Event Scope transaction. It is mandatory to use 584 (MTU) on any I2RS client's Write transaction or the configuration 585 of an Event Scope transaction. 587 SEC-REQ-10: The secure transport MUST provide data 588 confidentiality, data integrity, and practical replay prevention. 590 SEC-REQ-11: The I2RS client and I2RS agent protocol SHOULD 591 implement mechanisms that mitigate DoS attacks. For the secure 592 transport, this means the secure transport must support DoS 593 prevention. For the insecure transport protocol, the I2RS higher- 594 layer protocol MUST contain a transport management layer that 595 considers the detection of DoS attacks and provides a warning over 596 a secure-transport channel. 598 SEC-REQ-12: A secure transport MUST be associated with a key 599 management solution that can guarantee that only the entities 600 having sufficient privileges can get the keys to encrypt/decrypt 601 the sensitive data. 603 SEC-REQ-13: A machine-readable mechanism to indicate that a data- 604 model contains non-confidential data MUST be provided. A non- 605 secure transport MAY be used to publish only read scope or 606 notification scope data if the associated data model indicates 607 that that data is non-confidential. 609 SEC-REQ-14: The I2RS protocol MUST be able to support multiple 610 secure transport sessions providing protocol and data 611 communication between an I2RS agent and an I2RS client. However, 612 a single I2RS agent to I2RS client connection MAY elect to use a 613 single secure transport session or a single non-secure transport 614 session conforming the requirements above. 616 SEC-REQ-15: Deployment configuration knobs SHOULD be created to 617 allow operators to send "non-confidential" Read scope (data or 618 Event streams) over a secure transport. 620 Explanation: 622 The I2RS architecture defines three scopes: read, write, and 623 notification scope. Insecure data can only be used for read scope 624 and notification scope of "non-confidential data". The configuration 625 of ephemeral data in the I2RS agent uses either write scope for data 626 or write scope for configuration of event notification streams. The 627 requirement to use secure transport for configuration prevents 628 accidental or malevolent entities from altering the I2RS routing 629 system through the I2RS agent. 631 It is anticipated that the passing of most I2RS ephemeral state 632 operational status SHOULD be done over a secure transport. 634 In most circumstances the secure transport protocol will be 635 associated with a key management system. Most deployments of the 636 I2RS protocol will allow for automatic key management systems. Since 637 the data models for the I2RS protocol will control key routing 638 functions, it is important that deployments of I2RS use automatic key 639 management systems. 641 Per BCP107 [RFC4107] while key management system SHOULD be automatic, 642 the systems MAY be manual in the following scenarios: 644 a) The environment has limited bandwidth or high round-trip times. 646 b) The information being protected has low value. 648 c) The total volume of traffic over the entire lifetime of the 649 long-term session key will be very low. 651 d) The scale of the deployment is limited. 653 Operators deploying the I2RS protocol selecting manual key management 654 SHOULD consider both short and medium term plans. Deploying 655 automatic systems initially may save effort over the long-term. 657 4.5. Management Protocol Security 659 Requirements: 661 SEC-REQ-16: In a critical infrastructure, certain data within 662 routing elements is sensitive and read/write operations on such 663 data SHOULD be controlled in order to protect its confidentiality. 664 To achieve this, higher-layer protocols MUST utilize a secure 665 transport, and SHOULD provide access control functions to protect 666 confidentiality of the data. 668 SEC-REQ-17: An integrity protection mechanism for I2RS MUST be 669 provided that will be able to ensure the following: 671 1) the data being protected is not modified without detection 672 during its transportation, 674 2) the data is actually from where it is expected to come from, 675 and 677 3) the data is not repeated from some earlier interaction the 678 higher layer protocol (best effort). 680 The I2RS higher-layer protocol operating over a secure transport 681 provides this integrity. The I2RS higher-layer protocol operating 682 over an insecure transport SHOULD provide some way for the client 683 receiving non-confidential read-scoped or event-scoped data over 684 the insecure connection to detect when the data integrity is 685 questionable; and in the event of a questionable data integrity 686 the I2RS client should disconnect the insecure transport 687 connection. 689 SEC-REQ-18: The I2RS higher-layer protocol MUST provide a 690 mechanism for message traceability (requirements in [RFC7922]) 691 that supports the tracking higher-layer functions run across 692 secure connection or a non-secure transport. 694 Explanation: 696 Most carriers do not want a router's configuration and data flow 697 statistics known by hackers or their competitors. While carriers may 698 share peering information, most carriers do not share configuration 699 and traffic statistics. To achieve this, the I2RS higher-layer 700 protocol (e.g NETCONF) needs to have access control (NACM [RFC6536]) 701 to sensitive data needs to be provided, and the confidentiality 702 protection on such data during transportation needs to be enforced. 704 Integrity of data is important even if the I2RS protocol is sending 705 non-confidential data over an insecure connection. The ability to 706 trace I2RS protocol messages that enact I2RS transactions provides a 707 minimal aid to helping operators check how messages enact 708 transactions on a secure or insecure transport. 710 4.6. Role-Based Data Model Security 712 The I2RS Architecture [RFC7921] specifies access control by "role" 713 where role is a method of making access control more manageable by 714 creating a grouping of users so that access control can be specified 715 for a role rather than for each of the individuals. Therefore, I2RS 716 role specifies the access control for a group as being read, write, 717 or notification. 719 SEC-REQ-19: The rules around what I2RS security role is permitted 720 to access and manipulate what information over a secure transport 721 (which protects the data in transit) SHOULD ensure that data of 722 any level of sensitivity is reasonably protected from being 723 observed by those without permission to view it, so that privacy 724 requirements are met. 726 SEC-REQ-20: Role security MUST work when multiple transport 727 connections are being used between the I2RS client and I2RS agent 728 as the I2RS architecture [RFC7921] describes. 730 Sec-REQ-21: If an I2RS agents or an I2RS client is tightly 731 correlated with a person, then the I2RS protocol and data models 732 SHOULD provide additional security that protects the person's 733 privacy. 735 Explanation: 737 I2RS higher-layer uses management protocol E.g. NETCONF, RESTCONF) 738 to pass messages in order to enact I2RS transactions. Role Security 739 must secure data (sensitivity and normal data) in a router even when 740 it is operating over multiple connections at the same time. NETCONF 741 can run over TLS (over TCP or SCTP) or SSH. RESTCONF runs over HTTP 742 over a secure transport (TLS). SCTP [RFC4960] provides security for 743 multiple streams plus end-to-end transport of data. Some I2RS 744 functions may wish to operate over DTLS which runs over UDP 745 ([RFC6347]), DDCP ([RFC6238]), and SCTP ([RFC5764]). 747 Please note the security of the application to I2RS client connection 748 is outside of the I2RS protocol or I2RS interface. 750 One example of I2RS privacy concerns related to a person is if I2RS 751 agent is running on someone's phone to control tethering, and the 752 I2RS client might be the client tracking such tethering. This 753 protection of the privacy of the person involves the I2RS client and 754 the I2RS agent communication anonymizing the any data related to the 755 person's identity or locatino. 757 A variety of forms of managemen may set policy on roles: "operator- 758 applied knobs", roles that restrict personal access, data-models with 759 specific "privacy roles", and access filters. 761 4.7. Security of the environment 763 The security for the implementation of a protocol also considers the 764 protocol environment. The environmental security requirements are 765 found in: [I-D.ietf-i2rs-security-environment-reqs]. 767 5. Security Considerations 769 This is a document about security requirements for the I2RS protocol 770 and data modules. Security considerations for the I2RS protocol 771 include both the protocol and the security environment. 773 6. IANA Considerations 775 This draft is requirements, and does not request anything of IANA. 777 7. Acknowledgement 779 The authors would like to thank Wes George, Ahmed Abro, Qin Wu, Eric 780 Yu, Joel Halpern, Scott Brim, Nancy Cam-Winget, DaCheng Zhang, Alia 781 Atlas, and Jeff Haas for their contributions to the I2RS security 782 requirements discussion and this document. The authors would like to 783 thank Bob Moskowitz, Kathleen Moriarty, Stephen Farrell, Radia 784 Perlman, Alvaro Retana, Ben Campbell, and Alissa Cooper for their 785 review of these requirements. 787 8. References 789 8.1. Normative References 791 [I-D.ietf-i2rs-security-environment-reqs] 792 Migault, D., Halpern, J., and S. Hares, "I2RS Environment 793 Security Requirements", draft-ietf-i2rs-security- 794 environment-reqs-01 (work in progress), April 2016. 796 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate 797 Requirement Levels", BCP 14, RFC 2119, 798 DOI 10.17487/RFC2119, March 1997, 799 . 801 [RFC4107] Bellovin, S. and R. Housley, "Guidelines for Cryptographic 802 Key Management", BCP 107, RFC 4107, DOI 10.17487/RFC4107, 803 June 2005, . 805 [RFC4949] Shirey, R., "Internet Security Glossary, Version 2", 806 FYI 36, RFC 4949, DOI 10.17487/RFC4949, August 2007, 807 . 809 [RFC7258] Farrell, S. and H. Tschofenig, "Pervasive Monitoring Is an 810 Attack", BCP 188, RFC 7258, DOI 10.17487/RFC7258, May 811 2014, . 813 [RFC7921] Atlas, A., Halpern, J., Hares, S., Ward, D., and T. 814 Nadeau, "An Architecture for the Interface to the Routing 815 System", RFC 7921, DOI 10.17487/RFC7921, June 2016, 816 . 818 [RFC7922] Clarke, J., Salgueiro, G., and C. Pignataro, "Interface to 819 the Routing System (I2RS) Traceability: Framework and 820 Information Model", RFC 7922, DOI 10.17487/RFC7922, June 821 2016, . 823 [RFC7923] Voit, E., Clemm, A., and A. Gonzalez Prieto, "Requirements 824 for Subscription to YANG Datastores", RFC 7923, 825 DOI 10.17487/RFC7923, June 2016, 826 . 828 8.2. Informative References 830 [I-D.ietf-i2rs-ephemeral-state] 831 Haas, J. and S. Hares, "I2RS Ephemeral State 832 Requirements", draft-ietf-i2rs-ephemeral-state-16 (work in 833 progress), August 2016. 835 [I-D.ietf-netconf-restconf] 836 Bierman, A., Bjorklund, M., and K. Watsen, "RESTCONF 837 Protocol", draft-ietf-netconf-restconf-16 (work in 838 progress), August 2016. 840 [I-D.ietf-taps-transports] 841 Fairhurst, G., Trammell, B., and M. KĂźhlewind, 842 "Services provided by IETF transport protocols and 843 congestion control mechanisms", draft-ietf-taps- 844 transports-11 (work in progress), July 2016. 846 [RFC2865] Rigney, C., Willens, S., Rubens, A., and W. Simpson, 847 "Remote Authentication Dial In User Service (RADIUS)", 848 RFC 2865, DOI 10.17487/RFC2865, June 2000, 849 . 851 [RFC4960] Stewart, R., Ed., "Stream Control Transmission Protocol", 852 RFC 4960, DOI 10.17487/RFC4960, September 2007, 853 . 855 [RFC5246] Dierks, T. and E. Rescorla, "The Transport Layer Security 856 (TLS) Protocol Version 1.2", RFC 5246, 857 DOI 10.17487/RFC5246, August 2008, 858 . 860 [RFC5764] McGrew, D. and E. Rescorla, "Datagram Transport Layer 861 Security (DTLS) Extension to Establish Keys for the Secure 862 Real-time Transport Protocol (SRTP)", RFC 5764, 863 DOI 10.17487/RFC5764, May 2010, 864 . 866 [RFC6238] M'Raihi, D., Machani, S., Pei, M., and J. Rydell, "TOTP: 867 Time-Based One-Time Password Algorithm", RFC 6238, 868 DOI 10.17487/RFC6238, May 2011, 869 . 871 [RFC6241] Enns, R., Ed., Bjorklund, M., Ed., Schoenwaelder, J., Ed., 872 and A. Bierman, Ed., "Network Configuration Protocol 873 (NETCONF)", RFC 6241, DOI 10.17487/RFC6241, June 2011, 874 . 876 [RFC6347] Rescorla, E. and N. Modadugu, "Datagram Transport Layer 877 Security Version 1.2", RFC 6347, DOI 10.17487/RFC6347, 878 January 2012, . 880 [RFC6536] Bierman, A. and M. Bjorklund, "Network Configuration 881 Protocol (NETCONF) Access Control Model", RFC 6536, 882 DOI 10.17487/RFC6536, March 2012, 883 . 885 [RFC6614] Winter, S., McCauley, M., Venaas, S., and K. Wierenga, 886 "Transport Layer Security (TLS) Encryption for RADIUS", 887 RFC 6614, DOI 10.17487/RFC6614, May 2012, 888 . 890 [RFC6733] Fajardo, V., Ed., Arkko, J., Loughney, J., and G. Zorn, 891 Ed., "Diameter Base Protocol", RFC 6733, 892 DOI 10.17487/RFC6733, October 2012, 893 . 895 [RFC7920] Atlas, A., Ed., Nadeau, T., Ed., and D. Ward, "Problem 896 Statement for the Interface to the Routing System", 897 RFC 7920, DOI 10.17487/RFC7920, June 2016, 898 . 900 Authors' Addresses 902 Susan Hares 903 Huawei 904 7453 Hickory Hill 905 Saline, MI 48176 906 USA 908 Email: shares@ndzh.com 910 Daniel Migault 911 Ericsson 912 8400 boulevard Decarie 913 Montreal, QC HAP 2N2 914 Canada 916 Email: daniel.migault@ericsson.com 918 Joel Halpern 919 Ericsson 920 US 922 Email: joel.halpern@ericsson.com