< draft-bortzmeyer-dnsop-dns-privacy-00.txt   draft-bortzmeyer-dnsop-dns-privacy-01.txt >
Network Working Group S. Bortzmeyer Network Working Group S. Bortzmeyer
Internet-Draft AFNIC Internet-Draft AFNIC
Intended status: Informational November 27, 2013 Intended status: Informational December 17, 2013
Expires: May 31, 2014 Expires: June 20, 2014
DNS privacy problem statement DNS privacy problem statement
draft-bortzmeyer-dnsop-dns-privacy-00 draft-bortzmeyer-dnsop-dns-privacy-01
Abstract Abstract
This document describes the privacy issues associated with the use of This document describes the privacy issues associated with the use of
the DNS by Internet users. It is intended to be mostly a problem the DNS by Internet users. It is intended to be mostly a problem
statement and it does not prescribe solutions (although Section 5 statement and it does not prescribe solutions.
suggests some possible improvments).
Discussions of the document should take place on the dnsop mailing Discussions of the document should take place on the dnsop mailing
list [dnsop] list [dnsop].
Status of This Memo Status of This Memo
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provisions of BCP 78 and BCP 79. provisions of BCP 78 and BCP 79.
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This Internet-Draft will expire on May 31, 2014. This Internet-Draft will expire on June 20, 2014.
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Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Risks . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 2. Risks . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
2.1. Data in the DNS request . . . . . . . . . . . . . . . . . 3 2.1. Data in the DNS request . . . . . . . . . . . . . . . . . 4
2.2. On the wire . . . . . . . . . . . . . . . . . . . . . . . 4 2.2. On the wire . . . . . . . . . . . . . . . . . . . . . . . 5
2.3. In the servers . . . . . . . . . . . . . . . . . . . . . 5 2.3. In the servers . . . . . . . . . . . . . . . . . . . . . 6
2.3.1. In the resolvers . . . . . . . . . . . . . . . . . . 6 2.3.1. In the resolvers . . . . . . . . . . . . . . . . . . 7
2.3.2. In the authoritative name servers . . . . . . . . . . 6 2.3.2. In the authoritative name servers . . . . . . . . . . 7
2.3.3. Rogue servers . . . . . . . . . . . . . . . . . . . . 7 2.3.3. Rogue servers . . . . . . . . . . . . . . . . . . . . 8
3. Actual "attacks" . . . . . . . . . . . . . . . . . . . . . . 7 3. Actual "attacks" . . . . . . . . . . . . . . . . . . . . . . 8
4. Legalities . . . . . . . . . . . . . . . . . . . . . . . . . 7 4. Legalities . . . . . . . . . . . . . . . . . . . . . . . . . 8
5. Possible technical solutions . . . . . . . . . . . . . . . . 7 5. Security considerations . . . . . . . . . . . . . . . . . . . 8
5.1. On the wire . . . . . . . . . . . . . . . . . . . . . . . 8 6. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 9
5.1.1. Reducing the attack surface . . . . . . . . . . . . . 8 7. References . . . . . . . . . . . . . . . . . . . . . . . . . 9
5.1.2. Encrypting the DNS traffic . . . . . . . . . . . . . 8 7.1. Normative References . . . . . . . . . . . . . . . . . . 9
5.2. In the servers . . . . . . . . . . . . . . . . . . . . . 10 7.2. Informative References . . . . . . . . . . . . . . . . . 9
5.2.1. In the resolvers . . . . . . . . . . . . . . . . . . 10 Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 11
5.2.2. In the authoritative name servers . . . . . . . . . . 10
5.2.3. Rogue servers . . . . . . . . . . . . . . . . . . . . 11
6. Security considerations . . . . . . . . . . . . . . . . . . . 11
7. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 11
8. References . . . . . . . . . . . . . . . . . . . . . . . . . 11
8.1. Normative References . . . . . . . . . . . . . . . . . . 12
8.2. Informative References . . . . . . . . . . . . . . . . . 12
Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 13
1. Introduction 1. Introduction
The Domain Name System is specified in [RFC1034] and [RFC1035]. It The Domain Name System is specified in [RFC1034] and [RFC1035]. It
is one of the most important infrastructure components of the is one of the most important infrastructure components of the
Internet and one of the most often ignored or misunderstood. Almost Internet and one of the most often ignored or misunderstood. Almost
every activity on the Internet starts with a DNS query (and often every activity on the Internet starts with a DNS query (and often
several). Its use has many privacy implications and we try to give several). Its use has many privacy implications and we try to give
here a comprehensive and accurate list. here a comprehensive and accurate list.
skipping to change at page 3, line 33 skipping to change at page 3, line 32
Almost all the DNS queries are today sent over UDP, and this has Almost all the DNS queries are today sent over UDP, and this has
practical consequences if someone thinks of encrypting this traffic practical consequences if someone thinks of encrypting this traffic
(some encryption solutions are typically done for TCP, not UDP). (some encryption solutions are typically done for TCP, not UDP).
I should be noted to that DNS resolvers sometimes forward requests to I should be noted to that DNS resolvers sometimes forward requests to
bigger machines, with a larger and more shared cache, the forwarders. bigger machines, with a larger and more shared cache, the forwarders.
From the point of view of privacy, forwarders are like resolvers, From the point of view of privacy, forwarders are like resolvers,
except that the caching in the resolver before them decreases the except that the caching in the resolver before them decreases the
amount of data they can see. amount of data they can see.
We will use here the terminology of [RFC6973]. Another important point to keep in mind when analyzing the privacy
issues of DNS is the mix of many sort of DNS requests received by a
server. Let's assume the eavesdropper want to know which Web page is
visited by an user. For a typical Web page displayed by the user,
there are three sorts of DNS requests:
Primary request: this is the domain name that the user typed or
selected from a bookmark or choosed by clicking on an hyperklink.
Presulably, this is what is of interest for the eavesdropper.
Secondary requests: these are the requests performed by the user
agent (here, the Web browser) without any direct involvment or
knowledge of the user. For the Web, they are triggered by
included content, CSS sheets, JavaScript code, embedded images,
etc. In some cases, there can be dozens of domain names in a
single page.
Tertiary requests: these are the requests performed by the DNS
system itself. For instance, if the answer to a query is a
referral to a set of name servers, and the glue is not returned,
the resolver will have to do tertiary requests to turn name
servers' named into IP addresses.
For privacy-related terms, we will use here the terminology of
[RFC6973].
2. Risks 2. Risks
This draft is limited to the study of privacy risks for the end-user This draft is limited to the study of privacy risks for the end-user
(the one performing DNS requests). Privacy risks for the holder of a (the one performing DNS requests). Privacy risks for the holder of a
zone (the risk that someone gets the data) are discussed in [RFC5936] zone (the risk that someone gets the data) are discussed in [RFC5936]
and in [I-D.koch-perpass-dns-confidentiality]. Non-privacy risks and in [I-D.koch-perpass-dns-confidentiality]. Non-privacy risks
(such as cache poisoning) are out of scope. (such as cache poisoning) are out of scope.
2.1. Data in the DNS request 2.1. Data in the DNS request
skipping to change at page 4, line 31 skipping to change at page 5, line 5
the issues and warnings about collection of IP addresses apply here. the issues and warnings about collection of IP addresses apply here.
For the communication between the resolver and the authoritative name For the communication between the resolver and the authoritative name
servers, the source IP address has a different meaning, it does not servers, the source IP address has a different meaning, it does not
have the same status as the source address in a HTTP connection. It have the same status as the source address in a HTTP connection. It
is now the IP address of the resolver which, in a way "hides" the is now the IP address of the resolver which, in a way "hides" the
real user. However, it does not always work. Sometimes real user. However, it does not always work. Sometimes
[I-D.vandergaast-edns-client-subnet] is used. Sometimes the end user [I-D.vandergaast-edns-client-subnet] is used. Sometimes the end user
has a personal resolver on her machine. In that case, the IP address has a personal resolver on her machine. In that case, the IP address
is as sensitive as it is for HTTP. is as sensitive as it is for HTTP.
A note about IP addresses: there is currently no IETF document which
describes in detail the privacy issues of IP addressing. In the mean
time, the discussion here is intended to include both IPv4 and IPv6
source addresses. For a number of reasons their assignment and
utilization characteristics are different, which may have
implications for details of information leakage associated with the
collection of source addresses. (For example, a specific IPv6 source
address seen on the public Internet is less likely than an IPv4
address to originate behind a CGN or other NAT.) However, for both
IPv4 and IPv6 addresses, it's important to note that source addresses
are propagated with queries and comprise metadata about the host,
user, or application that originated them.
2.2. On the wire 2.2. On the wire
DNS traffic can be seen by an eavesdropper like any other traffic. DNS traffic can be seen by an eavesdropper like any other traffic.
It is typically not encrypted. (DNSSEC, specified in [RFC4033] It is typically not encrypted. (DNSSEC, specified in [RFC4033]
explicitely excludes confidentiality from its goals.) So, if an explicitely excludes confidentiality from its goals.) So, if an
initiator starts a HTTPS communication with a recipient, while the initiator starts a HTTPS communication with a recipient, while the
HTTP traffic will be encrypted, the DNS exchange prior to it will not HTTP traffic will be encrypted, the DNS exchange prior to it will not
be. When the other protocols will become more or more privacy-aware be. When the other protocols will become more or more privacy-aware
and secured against surveillance, the DNS risks to become "the and secured against surveillance, the DNS risks to become "the
weakest link" in privacy. weakest link" in privacy.
skipping to change at page 6, line 7 skipping to change at page 6, line 41
communications path. As a result, they are often forgotten in risk communications path. As a result, they are often forgotten in risk
analysis. But, to quote again [RFC6973], "Although [...] enablers analysis. But, to quote again [RFC6973], "Although [...] enablers
may not generally be considered as attackers, they may all pose may not generally be considered as attackers, they may all pose
privacy threats (depending on the context) because they are able to privacy threats (depending on the context) because they are able to
observe, collect, process, and transfer privacy-relevant data." In observe, collect, process, and transfer privacy-relevant data." In
[RFC6973] parlance, enablers become observers when they start [RFC6973] parlance, enablers become observers when they start
collecting data. collecting data.
Many programs exist to collect and analyze DNS data at the servers. Many programs exist to collect and analyze DNS data at the servers.
From the "query log" of some programs like BIND, to tcpdump and more From the "query log" of some programs like BIND, to tcpdump and more
sophisticated programs like PacketQ TODO reference and DNSmezzo TODO sophisticated programs like PacketQ [packetq] reference and DNSmezzo
reference. The organization managing the DNS server can use this [dnsmezzo]. The organization managing the DNS server can use this
data itself or it can be part of a surveillance program like PRISM data itself or it can be part of a surveillance program like PRISM
[prism] and pass data to an outside attacker. [prism] and pass data to an outside attacker.
Sometimes, these data are kept for a long time and/or distributed to Sometimes, these data are kept for a long time and/or distributed to
third parties, for research purposes [ditl], for security analysis, third parties, for research purposes [ditl], for security analysis,
or for surveillance tasks. Also, there are observation points in the or for surveillance tasks. Also, there are observation points in the
network which gather DNS data and then make it accessible to third- network which gather DNS data and then make it accessible to third-
parties for research or security purposes ("passive DNS parties for research or security purposes ("passive DNS
[passive-dns]"). [passive-dns]").
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A rogue DHCP server can direct you to a rogue resolver. Most of the A rogue DHCP server can direct you to a rogue resolver. Most of the
times, it seems to be done to divert traffic, by providing lies for times, it seems to be done to divert traffic, by providing lies for
some domain names. But it could be used just to capture the traffic some domain names. But it could be used just to capture the traffic
and gather information about you. Same thing for malwares like and gather information about you. Same thing for malwares like
DNSchanger[dnschanger] which changes the resolver in the machine's DNSchanger[dnschanger] which changes the resolver in the machine's
configuration. configuration.
3. Actual "attacks" 3. Actual "attacks"
A very quick examination of DNS traffic may lead to the false
conclusion that extracting the needle from the haystack is difficult.
"Interesting" primary DNS requests are mixed with useless (for the
eavesdropper) second and tertiary requests (see the terminology in
Section 1). But, in this time of "big data" processing, powerful
techniques now exist to get from the raw data to what you're actually
interested in.
Many research papers about malware detection use DNS traffic to Many research papers about malware detection use DNS traffic to
detect "abnormal" behaviour that can be traced back to the activity detect "abnormal" behaviour that can be traced back to the activity
of malware on infected machines. Yes, this reasearch was done for of malware on infected machines. Yes, this reasearch was done for
the good but, technically, it is a privacy attack and it demonstrates the good but, technically, it is a privacy attack and it demonstrates
the power of the observation of DNS traffic. See [dns-footprint], the power of the observation of DNS traffic. See [dns-footprint],
[dagon-malware] and [darkreading-dns]. [dagon-malware] and [darkreading-dns].
4. Legalities 4. Legalities
To our knowledge, there are no specific privacy laws for DNS data. To our knowledge, there are no specific privacy laws for DNS data.
Interpreting general privacy laws like [data-protection-directive] Interpreting general privacy laws like [data-protection-directive]
(European Union) in the context of DNS traffic data is not an easy (European Union) in the context of DNS traffic data is not an easy
task and it seems there is no court precedent here. task and it seems there is no court precedent here.
5. Possible technical solutions 5. Security considerations
We mention here only the solutions that could be deployed in the
current Internet. Disruptive solutions, like replacing the DNS with
a completely new resolution protocol, are interesting but are kept
for a future work. Remember that the focus of this document is on
describing the threats, not in detailing solutions. This section is
therefore non-normative and is NOT a technical specification of
solutions. For the same reason, there are not yet actual
recommendations in this document.
Raising seriously the bar against the eavesdropper will require
SEVERAL actions. Not one is decisive by itself but, together, they
can have an effect. The most important suggested here are:
qname minimization,
encryption of DNS traffic,
padding (sending random queries from time to time).
We detail some of these actions later, classified by the kind of
observer (on the wire, in a server, etc). Some actions will help
against several kinds of observers. For instance, padding, sending
gratuitous queries from time to time (queries where you're not
interested in the replies, just to disturb the analysis), is useful
against all sorts of observers. It is a costly technique, because it
increases the traffic on the network but it seriously blurs the
picture for the observer.
5.1. On the wire
5.1.1. Reducing the attack surface
See Section 5.2.1 since the solution described there apply against
on-the-wire eavesdropping as well as against observation by the
resolver.
5.1.2. Encrypting the DNS traffic
To really defeat an eavesdropper, there is only one solution:
encryption. But, from the end user point of view, even if you check
that your communication between your stub resolver and the resolver
is encrypted, you have no way to ensure that the communication
between the resolver and the autoritative name servers will be.
There are two different cases, communication between the stub
resolver and the resolver (no caching but only two parties so
solutions which rely on an agreement may work) and communication
between the resolver and the authoritative servers (less data because
of caching, but many parties involved, so any solution has to scale
well). Encrypting the "last mile", between the user's stub resolver
and the resolver may be sufficient since the biggest danger for
privacy is between the stub resolver and the resolver, because there
is no caching involved there.
The only encryption mechanism available for DNS which is today an
IETF standard is IPsec in ESP mode. Its deployment in the wide
Internet is very limited, for reasons which are out of scope here.
Still, it may be a solution for "the last mile" and, indeed, many VPN
solutions use it this way, encrypting the whole traffic, including
DNS to the safe resolver. In the IETF standards, a possible
alternative could be DTLS [RFC6347]. It enjoyed very little actual
deployment and its interaction with the DNS has never been
considered, studied or of course implemented. There are also non
standard encryption techniques like DNScrypt [dnscrypt] for the stub
resolver <-> resolver communication or DNScurve [dnscurve] for the
resolver <-> authoritative server communication. It seems today that
the possibility of massive encryption of DNS traffic is very remote.
A last "pervasive encryption" solution for the DNS could be
"Confidential DNS" by W. Wijngaards which is not published yet but
seems promising.
Another solution would be to use more TCP for the queries, together
with TLS [RFC5246]. DNS can run over TCP and it provides a good way
to leverage the software and experience of the TLS world. There have
been discussions to use more TCP for the DNS, in light of reflection
attacks (based on the spoofing of the source IP address, which is
much more difficult with TCP). For instance, a stub resolver could
open a TCP connection with the resolver at startup and keep it open
to send queries and receive responses. The server would of course be
free to tear down these connections at will (when it is under stress,
for instance) and the client could reestablish them when necessary.
Remember that TLS sessions can survive TCP connections so there is no
need to restart the TLS negociation each time. This DNS-over-TLS-
over-TCP is already implemented in the Unbound resolver. It is safe
only if pipelining multiple questions over the same channel. Name
compression should also be disabled, or CRIME-style [crime] attacks
can apply.
Encryption alone does not guarantee perfect privacy, because of the
available metadata. For instance, the size of questions and
responses, even encrypted, provide hints about what queries have been
sent. (DNScrypt uses random-length padding, and a 64 bytes block
size, to limit this risk, but this raises other issues, for instance
during amplification attacks. Other security protocols use similar
techniques, for instance ESPv3.) Observing the periodicity of
encrypted questions/responses also discloses the TTL, which is yet
another hint about the queries. Non-cached responses are disclosing
the RTT between the resolver and authoritative servers. This is a
very useful indication to guess where authoritative servers are
located. Web pages are made of many resources, leading to multiple
requests, whose number and timing fingerprint which web site is being
browsed. So, observing encrypted traffic is not enough to recover
any plaintext queries, but is enough to answer the question "is one
of my employees browsing Facebook?". Finally, attackers can perform
a denial-of-service attack on possible targets, check if this makes a
difference on the encrypted traffic they observe, and infer what a
query was.
5.2. In the servers
5.2.1. In the resolvers
It does not seem there is a possible solution against a leaky
resolver. A resolver has to see the entire DNS traffic in clear.
The best approach to limit the problem is to have local resolvers
whose caching will limit the leak. Local networks should have a
local caching resolver (even if it forwards the unanswered questions
to a forwarder) and individual laptops can have their very own
resolver, too.
One mechanism to potentially mitigate on the wire attacks between
stub resolvers and caching resolvers is to determine if the network
location of the caching resolver can be moved closer to the end
user's computer (reducing the attack surface). As noted earlier in
Section 2.2, if an end user's computer is configured with a caching
resolver on the edge of the local network, an attacker would need to
gain access to that local network in order to successfully execute an
on the wire attack against the stub resolver. On the other hand, if
the end user's computer is configured to use a public DNS service as
the caching resolver, the attacker needs to simply get in the network
path between the end user and the public DNS server and so there is a
much greater opportunity for a successful attack. Configuring a
caching resolver closer to the end user can also reduce the
possibility of on the wire attacks.
5.2.2. In the authoritative name servers
A possible solution would be to minimize the amount of data sent from
the resolver. When a resolver receives the query "What is the AAAA
record for www.example.com?", it sends to the root (assuming a cold
resolver, whose cache is empty) the very same question. Sending
"What are the NS records for .com?" would be sufficient (since it
will be the answer from the root anyway). To do so would be
compatible with the current DNS system and therefore could be
deployable, since it is an unilateral change to the resolvers.
To do so, the resolver needs to know the zone cut [RFC2181]. There
is not a zone cut at every label boundary. If we take the name
www.foo.bar.example, it is possible that there is a zone cut between
"foo" and "bar" but not between "bar" and "example". So, assuming
the resolver already knows the name servers of .example, when it
receives the query "What is the AAAA record of www.foo.bar.example",
it does not always know if the request should be sent to the name
servers of bar.example or to those of example. [RFC2181] suggests an
algorithm to find the zone cut, so resolvers may try it.
Note that DNSSEC-validating resolvers already have access to this
information, since they have to find the zone cut (the DNSKEY record
set is just below, the DS record set just above).
It can be noted that minimizing the amount of data sent also
partially addresses the case of a wire sniffer.
One should note that the behaviour suggested here (minimizing the
amount of data sent in qnames) is NOT forbidden by the [RFC1034]
(section 5.3.3) or [RFC1035] (section 7.2). Sending the full qname
to the authoritative name server is a tradition, not a protocol
requirment.
Another note is that the answer to the NS query, unlike the referral
sent when the question is a full qname, is in the Answer section, not
in the Authoritative section. It has probably no practical
consequences.
5.2.3. Rogue servers
Traditional security measures (do not let malware change the system
configuration) are of course a must. A protection against rogue
servers announced by DHCP could be to have a local resolver, and to
always use it, ignoring DHCP.
6. Security considerations
Hey, man, the entire document is about security! This document is entirely about security, more precisely privacy.
Possible solutions to the issues described here are discussed in
[I-D.bortzmeyer-dnsop-privacy-sol] or in
[I-D.wijngaards-dnsop-confidentialdns].
7. Acknowledgments 6. Acknowledgments
Thanks to Nathalie Boulvard and to the CENTR members for the original Thanks to Nathalie Boulvard and to the CENTR members for the original
work which leaded to this draft. Thanks to Olaf Kolkman, Francis work which leaded to this draft. Thanks to Ondrej Sury for the
Dupont and Ondrej Sury for the interesting discussions. Thanks to interesting discussions. Thanks to Mohsen Souissi for proofreading.
Mohsen Souissi for proofreading. Thanks to Dan York and Frank Denis Thanks to Dan York, Suzanne Woolf and Frank Denis for good written
for good written contributions. contributions.
8. References 7. References
8.1. Normative References
7.1. Normative References
[RFC1034] Mockapetris, P., "Domain names - concepts and facilities", [RFC1034] Mockapetris, P., "Domain names - concepts and facilities",
STD 13, RFC 1034, November 1987. STD 13, RFC 1034, November 1987.
[RFC1035] Mockapetris, P., "Domain names - implementation and [RFC1035] Mockapetris, P., "Domain names - implementation and
specification", STD 13, RFC 1035, November 1987. specification", STD 13, RFC 1035, November 1987.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997. Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC6973] Cooper, A., Tschofenig, H., Aboba, B., Peterson, J., [RFC6973] Cooper, A., Tschofenig, H., Aboba, B., Peterson, J.,
Morris, J., Hansen, M., and R. Smith, "Privacy Morris, J., Hansen, M., and R. Smith, "Privacy
Considerations for Internet Protocols", RFC 6973, July Considerations for Internet Protocols", RFC 6973, July
2013. 2013.
8.2. Informative References 7.2. Informative References
[RFC2181] Elz, R. and R. Bush, "Clarifications to the DNS [RFC2181] Elz, R. and R. Bush, "Clarifications to the DNS
Specification", RFC 2181, July 1997. Specification", RFC 2181, July 1997.
[RFC4033] Arends, R., Austein, R., Larson, M., Massey, D., and S. [RFC4033] Arends, R., Austein, R., Larson, M., Massey, D., and S.
Rose, "DNS Security Introduction and Requirements", RFC Rose, "DNS Security Introduction and Requirements", RFC
4033, March 2005. 4033, March 2005.
[RFC5246] Dierks, T. and E. Rescorla, "The Transport Layer Security [RFC5246] Dierks, T. and E. Rescorla, "The Transport Layer Security
(TLS) Protocol Version 1.2", RFC 5246, August 2008. (TLS) Protocol Version 1.2", RFC 5246, August 2008.
skipping to change at page 12, line 48 skipping to change at page 10, line 10
[I-D.koch-perpass-dns-confidentiality] [I-D.koch-perpass-dns-confidentiality]
Koch, P., "Confidentiality Aspects of DNS Data, Koch, P., "Confidentiality Aspects of DNS Data,
Publication, and Resolution", draft-koch-perpass-dns- Publication, and Resolution", draft-koch-perpass-dns-
confidentiality-00 (work in progress), November 2013. confidentiality-00 (work in progress), November 2013.
[I-D.vandergaast-edns-client-subnet] [I-D.vandergaast-edns-client-subnet]
Contavalli, C., Gaast, W., Leach, S., and E. Lewis, Contavalli, C., Gaast, W., Leach, S., and E. Lewis,
"Client Subnet in DNS Requests", draft-vandergaast-edns- "Client Subnet in DNS Requests", draft-vandergaast-edns-
client-subnet-02 (work in progress), July 2013. client-subnet-02 (work in progress), July 2013.
[I-D.bortzmeyer-dnsop-privacy-sol]
Bortzmeyer, S., "Possible solutions to DNS privacy
issues", draft-bortzmeyer-dnsop-privacy-sol-00 (work in
progress), December 2013.
[I-D.wijngaards-dnsop-confidentialdns]
Wijngaards, W., "Confidential DNS", draft-wijngaards-
dnsop-confidentialdns-00 (work in progress), November
2013.
[dnsop] IETF, , "The dnsop mailing list", October 2013. [dnsop] IETF, , "The dnsop mailing list", October 2013.
[dagon-malware] [dagon-malware]
Dagon, D., "Corrupted DNS Resolution Paths: The Rise of a Dagon, D., "Corrupted DNS Resolution Paths: The Rise of a
Malicious Resolution Authority", 2007. Malicious Resolution Authority", 2007.
[dns-footprint] [dns-footprint]
Stoner, E., "DNS footprint of malware", October 2010. Stoner, E., "DNS footprint of malware", October 2010.
[darkreading-dns] [darkreading-dns]
skipping to change at page 13, line 23 skipping to change at page 10, line 42
[dnschanger] [dnschanger]
Wikipedia, , "DNSchanger", November 2011. Wikipedia, , "DNSchanger", November 2011.
[dnscrypt] [dnscrypt]
Denis, F., "DNSCrypt", . Denis, F., "DNSCrypt", .
[dnscurve] [dnscurve]
Bernstein, D., "DNScurve", . Bernstein, D., "DNScurve", .
[packetq] , "PacketQ, a simple tool to make SQL-queries against
PCAP-files", 2011.
[dnsmezzo]
Bortzmeyer, S., "PacketQ, a simple tool to make SQL-
queries against PCAP-files", 2009.
[prism] NSA, , "PRISM", 2007. [prism] NSA, , "PRISM", 2007.
[crime] Rizzo, J. and T. Dong, "The CRIME attack against TLS", [crime] Rizzo, J. and T. Dong, "The CRIME attack against TLS",
2012. 2012.
[ditl] , "A Day in the Life of the Internet (DITL)", 2002. [ditl] , "A Day in the Life of the Internet (DITL)", 2002.
[data-protection-directive] [data-protection-directive]
, "European directive 95/46/EC on the protection of , "European directive 95/46/EC on the protection of
individuals with regard to the processing of personal data individuals with regard to the processing of personal data
and on the free movement of such data", November 1995. and on the free movement of such data", November 1995.
[passive-dns] [passive-dns]
Weimer, F., "Passive DNS Replication", April 2005. Weimer, F., "Passive DNS Replication", April 2005.
[tor-leak]
, "DNS leaks in Tor", 2013.
Author's Address Author's Address
Stephane Bortzmeyer Stephane Bortzmeyer
AFNIC AFNIC
Immeuble International Immeuble International
Saint-Quentin-en-Yvelines 78181 Saint-Quentin-en-Yvelines 78181
France France
Phone: +33 1 39 30 83 46 Phone: +33 1 39 30 83 46
Email: bortzmeyer+ietf@nic.fr Email: bortzmeyer+ietf@nic.fr
 End of changes. 19 change blocks. 
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