--- 1/draft-ietf-ipsecme-split-dns-11.txt 2018-08-06 11:13:20.785380375 -0700 +++ 2/draft-ietf-ipsecme-split-dns-12.txt 2018-08-06 11:13:20.817381152 -0700 @@ -1,19 +1,19 @@ Network T. Pauly Internet-Draft Apple Inc. Intended status: Standards Track P. Wouters -Expires: January 20, 2019 Red Hat - July 19, 2018 +Expires: February 7, 2019 Red Hat + August 6, 2018 Split DNS Configuration for IKEv2 - draft-ietf-ipsecme-split-dns-11 + draft-ietf-ipsecme-split-dns-12 Abstract This document defines two Configuration Payload Attribute Types for the IKEv2 protocol that add support for private DNS domains. These domains are intended to be resolved using DNS servers reachable through an IPsec connection, while leaving all other DNS resolution unchanged. This approach of resolving a subset of domains using non- public DNS servers is referred to as "Split DNS". @@ -25,21 +25,21 @@ Internet-Drafts are working documents of the Internet Engineering Task Force (IETF). Note that other groups may also distribute working documents as Internet-Drafts. The list of current Internet- Drafts is at https://datatracker.ietf.org/drafts/current/. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress." - This Internet-Draft will expire on January 20, 2019. + This Internet-Draft will expire on February 7, 2019. Copyright Notice Copyright (c) 2018 IETF Trust and the persons identified as the document authors. All rights reserved. This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (https://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents @@ -58,24 +58,24 @@ 3.1. Configuration Request . . . . . . . . . . . . . . . . . . 4 3.2. Configuration Reply . . . . . . . . . . . . . . . . . . . 4 3.3. Mapping DNS Servers to Domains . . . . . . . . . . . . . 5 3.4. Example Exchanges . . . . . . . . . . . . . . . . . . . . 5 3.4.1. Simple Case . . . . . . . . . . . . . . . . . . . . . 5 3.4.2. Requesting Domains and DNSSEC trust anchors . . . . . 6 4. Payload Formats . . . . . . . . . . . . . . . . . . . . . . . 6 4.1. INTERNAL_DNS_DOMAIN Configuration Attribute Type Request and Reply . . . . . . . . . . . . . . . . . . . . . . . . 7 4.2. INTERNAL_DNSSEC_TA Configuration Attribute . . . . . . . 7 - 5. INTERNAL_DNS_DOMAIN Usage Guidelines . . . . . . . . . . . . 8 - 6. INTERNAL_DNSSEC_TA Usage Guidelines . . . . . . . . . . . . . 9 + 5. INTERNAL_DNS_DOMAIN Usage Guidelines . . . . . . . . . . . . 9 + 6. INTERNAL_DNSSEC_TA Usage Guidelines . . . . . . . . . . . . . 10 7. Security Considerations . . . . . . . . . . . . . . . . . . . 11 - 8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 11 + 8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 12 9. References . . . . . . . . . . . . . . . . . . . . . . . . . 12 9.1. Normative References . . . . . . . . . . . . . . . . . . 12 9.2. Informative References . . . . . . . . . . . . . . . . . 13 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 13 1. Introduction Split DNS is a common configuration for secure tunnels, such as Virtual Private Networks in which host machines private to an organization can only be resolved using internal DNS resolvers @@ -356,22 +356,23 @@ o Digest Data (1 or more octets) - The DNSKEY digest as specified in [RFC4034] Section 5.1 in presentation format. Each INTERNAL_DNSSEC_TA attribute in the CFG_REPLY payload MUST immediately follow a corresponding INTERNAL_DNS_DOMAIN attribute. As the INTERNAL_DNSSEC_TA format itself does not contain the domain name, it relies on the preceding INTERNAL_DNS_DOMAIN to provide the domain for which it specifies the trust anchor. Any INTERNAL_DNSSEC_TA attribute that is not immediately preceded by an - INTERNAL_DNS_DOMAIN attribute MUST be ignored and treated as a - protocol error. + INTERNAL_DNS_DOMAIN or another INTERNAL_DNSSEC_TA attribute applying + to the same domain name MUST be ignored and treated as a protocol + error. 5. INTERNAL_DNS_DOMAIN Usage Guidelines If a CFG_REPLY payload contains no INTERNAL_DNS_DOMAIN attributes, the client MAY use the provided INTERNAL_IP4_DNS or INTERNAL_IP6_DNS servers as the default DNS server(s) for all queries. If a client is configured by local policy to only accept a limited number of INTERNAL_DNS_DOMAIN values, the client MUST ignore any other INTERNAL_DNS_DOMAIN values. @@ -432,24 +433,27 @@ certificate. It allows the remote IKE/IPsec server to modify DNS answers including its DNSSEC cryptographic signatures by overriding existing DNS information with trust anchor conveyed via IKE and (temporarilly) installed on the IKE client. Of specific concern is the overriding of [RFC6698] based TLSA records, which represent a confirmation or override of an existing WebPKI TLS certificate. Other DNS record types that convey cryptographic materials (public keys or fingerprints) are OPENPGPKEY, SMIMEA, SSHP and IPSECKEY records. - IKE clients MUST use a preconfigured whitelist of one or more domain - names for which it will allow INTERNAL_DNSSEC_TA updates. This list - can either be sent in the CFG_REQUEST payload, or else be applied - after reception of the CFG_REPLY payload. + IKE clients willing to accept INTERNAL_DNSSEC_TA attributes MUST use + a whitelist of one or more domains that can be updated out of band. + IKE clients with an empty whitelist MUST NOT use any + INTERNAL_DNSSEC_TA attributes received over IKE. Such clients MAY + interpret receiving an INTERNAL_DNSSEC_TA attribute for a non- + whitelisted domain as an indication that their local configuration + may need to be updated out of band. IKE clients should take care to only whitelist domains that apply to internal or managed domains, rather than to generic Internet traffic. The DNS root zone (".") MUST NOT be whitelisted. Other generic or public domains, such as top-level domains, similarly SHOULD NOT be whitelisted. Any updates to this whitelist of domain names MUST happen via explicit human interaction to prevent invisible installation of trust anchors.