Internet DRAFT - draft-urien-uta-tls-dtls-security-module
draft-urien-uta-tls-dtls-security-module
UTA Working Group P. Urien
Internet Draft Telecom ParisTech
Intended status: Experimental
December 2019
Expires: June 2020
TLS and DTLS Security Modules
draft-urien-uta-tls-dtls-security-module-09.txt
Abstract
Security and trust are very critical topics in the context of the
anywhere, anytime, anything internet connectivity. TLS and DTLS are
two major IETF protocols widely used to secure IP exchanges.
According to CoAP, DTLS is the protocol used by constraint nodes in
the Internet of Things (IoT) context.
In this draft we specify an ISO7816 interface for TLS and DTLS
secure modules based on ISO7816 secure chips, which are today
manufactured per billions every year.
Secure elements are cheap secure microcontrollers whose size is
about 25mm2 and whose security is ranked by evaluations typically
according to Common Criteria (CC) standards.
The support of TLS and DTLS is based on the EAP-TLS protocol, and
the IETF draft "EAP Support in smartcard" describing EAP-TLS support
for secure elements. First implementation demonstrates that such low
cost security modules are realistic, with a setup time for handshake
completion under the second.
Requirements Language
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 RFC 2119.
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Status of this Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
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 http://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 June 2020.
Copyright Notice
Copyright (c) 2019 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
(http://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents
carefully, 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 of the Trust Legal Provisions and are provided without
warranty as described in the Simplified BSD License.
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Table of Contents
Abstract........................................................... 1
Requirements Language.............................................. 1
Status of this Memo................................................ 2
Copyright Notice................................................... 2
1 Overview......................................................... 4
2 The EAP-TLS Smartcard............................................ 4
2.1 The EAP-TLS protocol........................................ 4
2.2 The EAP-TLS Smartcard....................................... 6
4 The TLS Security Module.......................................... 6
4.1 EAP-TLS for TLS Security Module............................. 6
4.2 The TLS / EAP-TLS Software Bridge........................... 8
4.3 The TLS Security Module Encryption and Decryption procedures 8
5 The DTLS Security Module........................................ 10
5.1 EAP-TLS for DTLS Security Module........................... 10
5.2 The DTLS / EAP-TLS Software Bridge......................... 11
5.3 The DTLS Security Module Encryption and Decryption procedures
............................................................... 12
6 Example of TLS processing by the TLS security module............ 14
7 Example of DTLS processing by the DTLS security module.......... 16
8 Security Considerations......................................... 22
9 IANA Considerations............................................. 22
10 References..................................................... 22
10.1 Normative References...................................... 22
10.2 Informative References.................................... 23
11 Authors' Addresses............................................. 23
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1 Overview
Security and trust are very critical topics in the context of the
anywhere, anytime, anything internet connectivity. TLS [TLS 1.0]
[TLS 1.1], [TLS 1.2] and DTLS [DTLS 1.0] [DTLS 1.2] are two major
IETF protocols widely used to secure IP exchanges. According to
[COAP], DTLS is the protocol used by constraint nodes in the
Internet of Things (IoT) context. In this draft we specify an
interface for TLS and DTLS secure modules based on [ISO7816] secure
chips, which are today manufactured per billions every year. Secure
elements are cheap secure microcontrollers whose size is about 25mm2
and whose security is ranked by evaluations typically according to
Common Criteria (CC) standards. The support of TLS and DTLS is based
on the EAP-TLS [EAP-TLS] protocol, and the IETF draft [EAP SC] "EAP
Support for Smartcards" describing EAP-TLS support for secure
elements. First implementation demonstrate that such low cost
security modules are realistic, with a setup time for handshake
completion, under the second.
2 The EAP-TLS Smartcard
2.1 The EAP-TLS protocol
The EAP-TLS [EAP-TLS] protocol (as illustrated by figure 1)defines a
transparent transport of the TLS protocol until the exchange
finished messages (both for server and client). According to EAP-
TLS, and similarly to DTLS [DTLS 1.0] [DTLS 1.2], messages are
grouped into a series of flights (four for the TLS full mode, and
three for the TLS Session Resumption.
The EAP-TLS protocol supports segmentation and reassembly operations
managed via the "Flags" byte, which is detailed below:
0 1 2 3 4 5 6 7
+-+-+-+-+-+-+-+-+
|L M S R R R R R|
+-+-+-+-+-+-+-+-+
L = Length included
M = More fragments
S = Start bit
R = Reserved
- The L bit (length included) is set to indicate the presence of the
four-octet TLS Message Length field, and MUST be set for the first
fragment of a fragmented TLS message or set of messages.
- The M bit (more fragments) is set on all but the last fragment.
- The S bit (EAP-TLS start) is set in an EAP-TLS Start message.
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When an EAP-TLS peer receives an EAP-Request packet with the M bit
set, it MUST respond with an EAP-Response with EAP-Type=EAP-TLS and
no data. This serves as a fragment ACK.
Authenticating Peer Authenticator
EAP-TLS Smartcard (SC) SC User
------------------- -------------
<- EAP-Request/
Identity
EAP-Response/
Identity (MyID) ->
<- EAP-Request/
EAP-Type=EAP-TLS
Flags
(TLS Start)
EAP-Response/
EAP-Type=EAP-TLS
Flags
(TLS client-hello)-> Flight 1
<- EAP-Request/
EAP-Type=EAP-TLS
Flags
(TLS server-hello, Flight 2
TLS certificate,
[TLS server-key-exchange,]
TLS certificate-request,
TLS server-hello-done)
EAP-Response/
EAP-Type=EAP-TLS
Flags
(TLS certificate, Flight 3
TLS client-key-exchange,
TLS certificate-verify,
TLS change-cipher-spec,
TLS finished) ->
<- EAP-Request/
EAP-Type=EAP-TLS
Flags
(TLS change-cipher-spec, Flight 4
TLS finished)
EAP-Response/
EAP-Type=EAP-TLS
Flags ->
<- EAP-Success
Figure 1. The EAP-TLS protocol
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2.2 The EAP-TLS Smartcard
The "EAP Support in Smartcard" draft [EAP SC] specifies an ISO7816
interface for a secure element (named EAP-TLS smartcard, in figure
1) that fully processes the EAP-TLS protocol until the reception of
the EAP-Success message.
The two main commands are detailed in figure 2:
- Reset-State, which resets the EAP-TLS state machine ,
- Process-EAP that transports TLS flights encapsulated in EAP-TLS
messages.
+------------------------+-----+-----+----+----+----+----+
| Command |Class| INS | P1 | P2 | Lc | Le |
+------------------------+-----+-----+----+----+----+----+
| Process-EAP | A0 |80-88| 00 | 00 | xx | yy |
+------------------------+-----+-----+----+----+----+----+
| Reset-State | A0 | 19 | 10 | 00 | 00 | 01 |
+------------------------+-----+-----+----+----+----+----+
Figure 2
4 The TLS Security Module
4.1 EAP-TLS for the TLS Security Module
TLS security modules are based on EAP-TLS devices, performing, as
illustrated by figure 3, a transparent encapsulation of TLS packets.
The EAP-Request-Identity message and EAP-Success message are not
used by the TLS secure modules.
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Security Module (SM) SM User
------------------- -------------
<- EAP-Request/
EAP-Type=EAP-TLS
Flags
(TLS Start)
EAP-Response/
EAP-Type=EAP-TLS
Flags
(TLS client-hello)->
<- EAP-Request/
EAP-Type=EAP-TLS
Flags
(TLS server-hello,
TLS certificate,
[TLS server-key-exchange,]
TLS certificate-request,
TLS server-hello-done)
EAP-Response/
EAP-Type=EAP-TLS
Flags
(TLS certificate,
TLS client-key-exchange,
TLS certificate-verify,
TLS change-cipher-spec,
TLS finished) ->
<- EAP-Request/
EAP-Type=EAP-TLS
Flags
(TLS change-cipher-spec,
TLS finished)
EAP-Response/
EAP-Type=EAP-TLS
Flags ->
=======================================================
Four ways TLS Handshake Completion
=======================================================
Figure 2. The TLS Handshake Completion with the Security Module
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4.2 The TLS / EAP-TLS Software Bridge
A software bridge, illustrated by figure 3 extracts TLS flights from
TLS packets, and manages EAP-TLS messages exchanged with the
Security Module.
+----------+ +-----------+
TLS | TLS | EAP-TLS | TLS |
packet | EAP-TLS | Packet | Security |
<=======> | Bridge | <========> | Module |
+----------+ +-----------+
Figure 3. The TLS / EAP-TLS Software Bridge
4.3 The TLS Security Module Encryption and Decryption procedures
After the completion of the TLS four ways or three ways handshake
(notified by the delivery of EAP-Success message in EAP-TLS) the
Security Module supports two procedures, Process-EAP-Encrypt and
Process-EAP-Decrypt, in order to respectively compute TLS encrypted
packets (see figure 4) or to check and decrypt the payload of TLS
ciphered packets (see figure 5).
Process-EAP-Encrypt(Type)
<- EAP-Request/
EAP-Type=EAP-TLS
Flags
(Payload= Clear Text)
EAP-Response/
EAP-Type=EAP-TLS
Flags
(Payload= TLS Encrypted
Record Layer Message)->
Figure 4. Generation of TLS encrypted packet by TLS Security module
Process-EAP-Decrypt
<- EAP-Request/
EAP-Type=EAP-TLS
Flags
(Payload= TLS Encrypted
Record Layer Message)->
EAP-Response/
EAP-Type=EAP-TLS
Flags
(Payload= TLS Clear
Record Layer payload)->
Figure 5. Generation of TLS decrypted packets
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In the case of the Process-EAP-Encrypt(Type) procedure the payload
of the EAP-TLS packet (see figure 4) is the clear text to be
encrypted in the TLS Record Layer packet. The SM adds the Type field
indicated in the Process-EAP-Encrypt command, and performs all
needed operations in order to compute the TLS encrypted packet
(including HMAC and optional padding bytes see figure 6),
encapsulated in the EAP-Response message (depicted in figure 4).
In the case of the Process-EAP-Decrypt() procedure, the payload of
the EAP-TLS packet (see figure 5) is the received TLS Record Layer
encrypted packet, as showed by figure 6. The Security Module checks
the HMAC, and upon success deciphers the encrypted payload; the
resulting data is returned encapsulated in the EAP-Response message.
+------+---------+--------+----------------------------+
| Type | Version | Length | Encrypted |
+------+---------+--------+ Payload |
+ |
+ +------+-----+------------+----------------+
+ | HMAC | Pad | Pad Length |
+-----------+------+-----+------------+
Figure 6. A TLS (Record Layer) encrypted packet.
The figure 7 details the structure of the Security Module command
needed for the encryption and decryption of TLS packets.
+-------------+-----+-----+----+------------+----+----+---------+
| Command |Class| INS | P1 | P2 | Lc | Le | SW |
+-------------+-----+-----+----+------------+----+----+---------+
| Process-EAP | A0 |80-88| 00 | 80 || Type | xx | yy | 9000 OK |
| Encrypt | | | | | | | 6985 ERR|
+-------------+-----+-----+----+------------+----+----+---------+
| Process-EAP | A0 |80-88| 00 | 00 | xx | yy | 9000 OK |
| Decrypt | | | | | | | 6985 ERR|
+-------------+-----+-----+----+------------+----+----+---------+
Figure 7. The Security Module ISO7816 commands
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5 The DTLS Security Module
5.1 EAP-TLS for the DTLS Security Module
Security Module (SM) SM User
------------------- -------------
<- EAP-Request/
EAP-Type=EAP-TLS
Flags
(TLS Start)
EAP-Response/
EAP-Type=EAP-TLS
Flags
(DTLS client-hello) -> Flight 1
<- EAP-Request/
DTLS Hello-Verify-Request Flight 2
(contains cookie)
EAP-Response/
EAP-Type=EAP-TLS
Flags
(DTLS client-hello
with cookie) -> Flight 3
<- EAP-Request/
EAP-Type=EAP-TLS
Flags
(DTLS server-hello,
DTLS certificate, Flight 4
[DTLS server-key-exchange,]
DTLS certificate-request,
DTLS server-hello-done)
EAP-Response/
EAP-Type=EAP-TLS
Flags
(DTLS certificate,
DTLS client-key-exchange,
DTLS certificate-verify, Flight 5
DTLS change-cipher-spec,
DTLS finished) ->
<- EAP-Request/
Flags
EAP-Type=EAP-TLS
(DTLS change-cipher-spec, Flight 6
DTLS finished)
EAP-Response/
EAP-Type=EAP-TLS
Flags ->
=======================================================
Four ways DTLS Handshake Completion
=======================================================
Figure 8. The DTLS handshake completion with the Security Module
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In a way similar to TLS (see figure 8), DTLS messages are
encapsulated in EAP-TLS messages.
5.2 The DTLS / EAP-TLS Software Bridge
A software bridge, illustrated by figure 9 extracts DTLS flights
from DTLS packets, and manages EAP-TLS exchanges with the Security
Module.
+----------+ +-----------+
DTLS | DTLS | EAP-TLS | DTLS |
packets | EAP-TLS | Packets | Security |
<=======> | Bridge | <========> | Module |
+----------+ +-----------+
Figure 9. DTLS / EAP-TLS software bridge
The DTLS security module doesn't manage handshake messages
fragmentation and reassembly. These operations are handled by the
software bridge during the DTLS three ways or four ways handshake.
Timeout and retransmission are also managed by the bridge entity.
According to [DTLS 1.0] finished messages have no sensitivity to
fragmentation. There are computed as if each handshake message had
been sent as a single fragment. The security module (see figure 10)
deals with handshake message with the fields fragment-offset set to
zero, and fragment-length equal to length. Because the handshake
sequence in not used in cryptographic calculations, it is fully
managed by the bridge. The security module does not take into
account the received messages sequences, and produces handshake
messages starting from zero (at the DTLS first hello message
generation) and incremented for every message.
HandshakeType msgtype;
uint24 length;
uint16 message-sequence;
uint24 fragment-offset;
uint24 fragment-length;
[Handshake Message]
Figure 10. Structure of the DTLS Handshake message.
It also should be noted that according to the DTLS protocol [DTLS
1.0] in cases where the cookie exchange is used, the initial
ClientHello and HelloVerifyRequest are NOT included in the Finished
MAC.
When the Security Module builds the client finished message it sets
the EPOCH field to one and resets the sequence number used by the
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record layer. The record layer packet structure is detailed by
figure 11.
struct {
ContentType type;
ProtocolVersion version;
uint16 epoch;
uint48 sequence-number;
uint16 length;
opaque fragment[DTLSPlaintext.length];
} DTLSPlaintext;
Figure 11. DTLS Record Layer packet structure
According to [DTLS 1.0] the DTLS MAC is the same as that of TLS 1.1.
However, rather than using TLS's implicit sequence number, the
sequence number used to compute the MAC is the 64-bit value formed
by concatenating the epoch and the sequence number in the order they
appear on the wire. TLS MAC calculation is parameterized on the
protocol version number, which, in the case of DTLS, is the on-the-
wire version, i.e., {254,255 } for DTLS 1.0.
5.3 The DTLS Security Module Encryption and Decryption procedures
Upon the completion of the DTLS handshake, i.e. after the generation
of finished messages (both and on client and server side) the record
layer is fully handle by the security module, which checks and
decrypts all incoming packets (see figure 13), and produces
encrypted and HMACed packets (see figure 12).
Process-EAP-Encrypt(Type)
<- EAP-Request/
EAP-Type=EAP-TLS
Flags
(Payload= Clear Text)
EAP-Response/
EAP-Type=EAP-TLS
Flags
(Payload= DTLS Encrypted
Record Layer Message)->
Figure 12. Generation of DTLS encrypted packet by the DTLS Security
module
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Process-EAP-Decrypt
<- EAP-Request/
EAP-Type=EAP-TLS
Flags
(Payload= DTLS Encrypted
Record Layer Message)->
EAP-Response/
EAP-Type=EAP-TLS
Flags
(Payload= DTLS Clear
Record Layer payload)->
Figure 13. Generation of TLS decrypted packets
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6 Example of TLS processing by the TLS security module
The following choreography illustrates the processing of a TLS (1.0)
resume session by the TLS security module. The CipherSuite is AES-
SHA1.
// RESET the Security Module
>> A0 19 10 00 00
<< 90 00
// Send EAP-TLS-Start in EAP-Request
// last four bytes represent the time
>> A0 80 00 00 0A 01 14 00 06 0D 20 55 82 E9 D1
// Flight 1
// Client Hello in EAP-Response
<< 02 14 00 5C 0D 80 00 00 00 52 16 03 01 00 4D 01 00 00 49 03
01 55 82 E9 D1 BE 21 DF 71 68 C3 14 BB DC 09 57 24 DA 77 F1
EA C1 9F 54 AF 0F E4 61 C9 5A 3F 06 93 20 34 1A 3F 0A E5 6C
C0 39 F1 E2 9A F7 D3 D6 6E C0 91 CC EB 77 61 7D 88 FF C7 00
F9 C3 6D 1F 1F 8C 00 02 00 2F 01 00
90 00
// Flight 2
// Server Hello + CCS + Finished in EAP-Request
// 1st fragment
>> A0 80 00 00 8A 01 0D 00 8A 0D C0 00 00 00 8A 16 03 01 00 4A
02 00 00 46 03 01 55 82 EA 66 4D ED 28 C0 E2 4F 22 12 01 35
49 82 61 5A FC 29 64 3B 20 1D 3A D4 00 39 91 27 07 06 20 34
1A 3F 0A E5 6C C0 39 F1 E2 9A F7 D3 D6 6E C0 91 CC EB 77 61
7D 88 FF C7 00 F9 C3 6D 1F 1F 8C 00 2F 00 14 03 01 00 01 01
16 03 01 00 30 85 D5 76 49 D3 58 C9 93 D8 03 B1 91 19 78 3F
16 A1 3A DF 03 54 53 63 B6 42 A5 5A 8A 23 C2 C5 AD 84 75 30
85 BE 75
// EAP-TLS ACK
<< 02 0D 00 06 0D 00
90 00
// 2nd fragment
>> A0 80 00 00 10 01 0E 00 10 0D 00 26 92 99 2A 9E 7F FF 2E
BC CB
// Flight 3
// Client CCS + Finished in EAP-Response
<< 02 0E 00 45 0D 80 00 00 00 3B 14 03 01 00 01 01 16 03 01 00
30 86 8A 10 A2 85 5F DA D8 52 16 D6 57 12 75 A6 57 A2 20 1B
A5 5B F0 0A E5 34 62 FF 92 28 BC DD 72 5E D7 6E C0 D4 A5 52
1F AA F5 6D 7C 8A 37 02 54
90 00
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// TLS handshake completion
// Process-EAP-Decrypt
>> A0 80 00 00 2B 01 0F 00 2B 0D 00 17 03 01 00 20 75 1A 28 2D
F3 E1 12 D5 19 7C 3E 38 CB 49 D6 43 CF B0 F3 E5 A3 1A BF A1
E0 75 AE A8 07 89 B0 45
// Empty Record Layer Payload
<< 02 0F 00 0A 0D 80 00 00 00 00
90 00
//Process-EAP-Decrypt
>> A0 80 00 00 2B 01 10 00 2B 0D 00 17 03 01 00 20 A0 65 57 15
17 D2 DA 92 FF A3 7F 07 F4 95 53 86 4C 55 F3 2C 87 6B A8 CB
2F 36 F3 71 D2 AD A3 F7
// Record Layer Clear Payload = 31 32 33 34 0D OA
<< 02 10 00 10 0D 80 00 00 00 06 31 32 33 34 0D 0A
90 00
// Process-EAP-Encrypt type=17h, payload = 31 32 33 34 0D 0A
>> A0 80 00 97 0C 01 11 00 0C 0D 00 31 32 33 34 0D 0A
// Encrypted TLS Record Layer packet in EAP-Response
<< 02 11 00 2F 0D 80 00 00 00 25 17 03 01 00 20 15 06 B7 7D 1F
1E F3 51 4A 8E 70 3C AE B2 EF EF D0 45 A7 1E 3F 68 92 AF 0C
09 C7 91 97 F7 C2 E6
90 00
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7 Example of DTLS processing by the DTLS security module
The following choreography illustrates the processing of a DTLS full
session the DTLS security module. The CipherSuite is AES-SHA1.
// RESET the Security Module
>> A0 19 10 00 00
<< 90 00
// Send EAP-TLS-Start in EAP-Request
// The last four bytes represent the time
>> A0 80 00 00 0A 01 14 00 06 0D 20 55 83 BF CA
// Flight 1
// DTLS ClientHello (no cookie) in EAP-Response
// RL-seq=0, RL-epoch=0, Handshake-seq=0
<< 02 14 00 4D 0D 80 00 00 00 43 16 FE FF 00 00 00 00 00 00 00
00 00 36 01 00 00 2A 00 00 00 00 00 00 00 2A FE FF 55 83 BF
CA DD 4C 24 32 85 D1 A5 21 EB EE F3 33 50 88 17 6B 48 6A CB
24 E6 28 8B FE 3C 85 F3 F1 00 00 00 02 00 2F 01 00
90 00
DTLS Bridge sends 67 bytes
DTLS Bridge receives RL-Seq=0, RL-epoch=0, Handshake-seq=0
// Flight 2 DTLS HelloVerifyRequest (contains cookie)
// DTLS HelloVerifyRequest in EAP-Response
>> A0 80 00 00 36 01 01 00 36 0D 00 16 FE FF 00 00 00 00 00 00
00 00 00 23 03 00 00 17 00 00 00 00 00 00 00 17 FE FF 14 C2
38 AC 8C F8 F5 CE CA 9B 9E F1 2F 8A D1 9E 2F 84 27 F2 FF
// Flight 3 DTLS HelloClient (contains cookie)
// DTLS ClientHello in EAP-Response
// RL-seq=1, RL-epoch=0, Handshake-seq=1
<< 02 01 00 61 0D 80 00 00 00 57 16 FE FF 00 00 00 00 00 00 00
01 00 4A 01 00 00 3E 00 01 00 00 00 00 00 3E FE FF 55 83 BF
CA DD 4C 24 32 85 D1 A5 21 EB EE F3 33 50 88 17 6B 48 6A CB
24 E6 28 8B FE 3C 85 F3 F1 00 14 C2 38 AC 8C F8 F5 CE CA 9B
9E F1 2F 8A D1 9E 2F 84 27 F2 FF 00 02 00 2F 01 00
90 00
DTLS Bridges sends 87 bytes
DTLS Bridges receives
RL-seq=1 RL-epoch=0 Handshake-seq=1
RL-seq=2 RL-epoch=0 Handshake-seq=2
RL-seq=3 RL-epoch=0 Handshake-seq=3
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RL-seq=4 RL-epoch=0 Handshake-seq=4
// Flight 4
// DTLS ServerHello, Certificate, CertificateRequest
// ServerHelloDone in EAP-Request
// 4 record layer messages
// EAP-TLS message 1st fragment
>> A0 80 00 00 8A 01 02 00 8A 0D C0 00 00 02 D2 16 FE FF 00 00
00 00 00 00 00 01 00 32 02 00 00 26 00 01 00 00 00 00 00 26
FE FF 55 83 BF CF F6 1B 78 8E 10 05 FC F7 4C 0C 0D 9D 98 4E
90 DA 71 EC BC 83 45 97 4A 71 D9 89 19 C1 00 00 2F 00 16 FE
FF 00 00 00 00 00 00 00 02 02 4E 0B 00 02 42 00 02 00 00 00
00 02 42 00 02 3F 00 02 3C 30 82 02 38 30 82 01 A1 A0 03 02
01 02 02 02 00 8B 30 0D 06 09 2A 86 48 86 F7 0D 01 01 05 05
00 30 57
// EAP-TLS Ack
<< 02 02 00 06 0D 00
90 00
// 2nd fragment
>> A0 80 00 00 8A 01 03 00 8A 0D 40 31 0B 30 09 06 03 55 04 06
13 02 55 53 31 11 30 0F 06 03 55 04 08 13 08 56 69 72 67 69
6E 69 61 31 10 30 0E 06 03 55 04 07 13 07 46 61 69 72 66 61
78 31 11 30 0F 06 03 55 04 0A 13 08 5A 6F 72 6B 2E 6F 72 67
31 10 30 0E 06 03 55 04 03 13 07 52 6F 6F 74 20 43 41 30 1E
17 0D 31 34 30 37 31 33 32 32 34 39 30 37 5A 17 0D 32 32 30
39 32 39 32 32 34 39 30 37 5A 30 5D 31 0B 30 09 06 03 55 04
06 13 02
// EAP-TLS Ack
<< 02 03 00 06 0D 00
90 00
// 3rd fragment
>> A0 80 00 00 8A 01 04 00 8A 0D 40 46 52 31 14 30 12 06 03 55
04 08 13 0B 49 6C 65 44 65 46 72 61 6E 63 65 31 0E 30 0C 06
03 55 04 07 13 05 50 61 72 69 73 31 17 30 15 06 03 55 04 0A
13 0E 65 74 68 65 72 74 72 75 73 74 2E 63 6F 6D 31 0F 30 0D
06 03 55 04 03 13 06 63 6C 69 65 6E 74 30 81 9F 30 0D 06 09
2A 86 48 86 F7 0D 01 01 01 05 00 03 81 8D 00 30 81 89 02 81
81 00 E3 83 38 A1 60 FE 8B 24 6F 39 E6 A8 A9 81 8F BE 9C E2
E3 7F 45
// EAP-TLS ack
<< 02 04 00 06 0D 00
90 00
// 4th fragment
>> A0 80 00 00 8A 01 05 00 8A 0D 40 2F 9B C7 41 09 B2 10 52 38
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3F 74 46 89 C4 A1 4E 28 9D F7 22 8B AF 90 D1 3C 3C 03 4A 2F
FC AA 03 26 3E 21 6C 19 DB 87 D7 F6 19 D6 F4 57 A4 BA 08 14
CB B3 1C 1F 01 76 6B 08 5A 4B 40 09 8B AB C8 6E 31 25 17 78
04 78 84 0F CB 0E B1 B9 D0 27 73 30 0D AE C1 7D BB 8E 1B 65
0A 17 51 23 9F C9 89 62 44 38 5C E6 63 A0 72 E2 99 67 02 03
01 00 01 A3 0D 30 0B 30 09 06 03 55 1D 13 04 02 30 00 30 0D
06 09 2A
// EAP-TLS Ack
<< 02 05 00 06 0D 00
90 00
// 5th fragment
>> A0 80 00 00 8A 01 06 00 8A 0D 40 86 48 86 F7 0D 01 01 05 05
00 03 81 81 00 7C 95 33 F9 17 27 BE CB 2A 85 6C A9 9E B8 4B
07 9B 09 69 ED D1 8A 38 A5 CA 1B C6 44 06 F9 A3 BD E4 66 58
C4 BE 92 32 C9 9E 43 42 26 9E EF 67 1D 6E A3 2C CE 59 DE 3E
0F 07 3A 10 66 72 5E A1 E5 06 76 76 CC 8D C0 47 54 42 AB FA
36 1C F1 8B 57 C0 A7 2B 65 52 4F 2E 36 75 D5 15 34 18 38 61
3A 18 18 5D D5 E3 9E 8D 1C DD 3D D3 A6 93 3D 19 0C 9C FA 98
C0 B0 5B
// EAP-TLS Ack
<< 02 06 00 06 0D 00
90 00
// 6th and last fragment
>> A0 80 00 00 48 01 07 00 48 0D 00 4F 35 CF B2 88 51 6D 9F 75
FD 16 FE FF 00 00 00 00 00 00 00 03 00 12 0D 00 00 06 00 03
00 00 00 00 00 06 03 01 02 40 00 00 16 FE FF 00 00 00 00 00
00 00 04 00 0C 0E 00 00 00 00 04 00 00 00 00 00 00
// Flight 5
// Certificate, KeyExchange, CertificateVerify, ChangeCipherSpec
// Finished, in EAP-Response, 2 record layer messages
// RL-seq=2, RL-epoch=0, Handshake-seq=2,3,4,5
// RL-seq=0, RL-epoch=0, Handshake-seq=0
// EAP-TLS message, 1st EAP fragment
<< 02 07 00 8A 0D C0 00 00 04 0F 16 FE FF 00 00 00 00 00 00 00
02 03 A7 0B 00 02 7F 00 02 00 00 00 00 02 7F 00 02 7C 00 02
79 30 82 02 75 30 82 01 DE A0 03 02 01 02 02 01 0C 30 0D 06
09 2A 86 48 86 F7 0D 01 01 05 05 00 30 81 94 31 0B 30 09 06
03 55 04 06 13 02 46 52 31 0F 30 0D 06 03 55 04 08 13 06 46
72 61 6E 63 65 31 0E 30 0C 06 03 55 04 07 13 05 50 61 72 69
73 31 13 30 11 06 03 55 04 0A 13 0A 45 74 68 65 72 54 90 00
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// EAP-TLS ack
>> A0 80 00 00 06 01 08 00 06 0D 00
// 2nd EAP fragment
<< 02 08 00 86 0D 40 72 75 73 74 31 0D 30 0B 06 03 55 04 0B 13
04 54 65 73 74 31 14 30 12 06 03 55 04 03 13 0B 50 61 73 63
61 6C 55 72 69 65 6E 31 2A 30 28 06 09 2A 86 48 86 F7 0D 01
09 01 16 1B 70 61 73 63 61 6C 2E 75 72 69 65 6E 40 65 74 68
65 72 74 72 75 73 74 2E 63 6F 6D 30 1E 17 0D 31 34 30 37 31
34 30 38 30 33 31 37 5A 17 0D 32 32 30 39 33 30 30 38 30 33
31 37 5A 30 5D 31 0B 30 09 06 03 55 04 06
90 00
// EAP-TLS Ack
>> A0 80 00 00 06 01 09 00 06 0D 00
// 3rd EAP fragment
<< 02 09 00 86 0D 40 13 02 46 52 31 14 30 12 06 03 55 04 08 13
0B 49 6C 65 44 65 46 72 61 6E 63 65 31 0E 30 0C 06 03 55 04
07 13 05 50 61 72 69 73 31 17 30 15 06 03 55 04 0A 13 0E 65
74 68 65 72 74 72 75 73 74 2E 63 6F 6D 31 0F 30 0D 06 03 55
04 03 13 06 53 65 72 76 65 72 30 81 9F 30 0D 06 09 2A 86 48
86 F7 0D 01 01 01 05 00 03 81 8D 00 30 81 89 02 81 81 00 D5
E3 52 F5 55 2B 10 1D 7D E9 3F 1A 49 23 59
90 00
// EAP-TLS Ack
>> A0 80 00 00 06 01 0A 00 06 0D 00
// 4th EAP fragment
<< 02 0A 00 86 0D 40 8D F4 B2 E7 5C FE 4A 5B 0D D1 EA AB F2 A1
6D 79 36 EA CC 06 E2 2B 4F C9 6C EB 7C 69 DB 22 BE B2 72 26
26 A5 53 75 32 D4 80 7E CF AD 85 C1 B0 89 D4 35 FF B1 71 6B
65 74 46 23 BD 52 B5 1B 90 D2 78 4B AF 1F EE C5 94 8D 9B 93
55 70 4B 1B 5F E6 42 31 2D EA 48 BC C2 4E B4 CD C2 9F FF C2
BE F2 D8 2B E2 99 AD 98 2E 22 EB 97 81 12 70 8E AF 37 29 02
03 01 00 01 A3 0D 30 0B 30 09 06 03 55 1D
90 00
// EAP-TLS Ack
>> A0 80 00 00 06 01 0B 00 06 0D 00
// 5th EAP fragment
<< 02 0B 00 86 0D 40 13 04 02 30 00 30 0D 06 09 2A 86 48 86 F7
0D 01 01 05 05 00 03 81 81 00 05 C2 17 66 F6 50 B5 BC EB 77
CB 57 20 5A 46 9A FB FE 0B 53 1B E7 39 9F B4 8D FE A5 B8 5A
5A 70 18 32 9C EE 0F 67 E8 F3 A2 61 94 5D A7 ED 89 F0 42 A3
8C 85 CA 42 A9 94 49 C3 52 2C EF 9A 2E 64 DA BA B5 AE E9 29
C4 F6 5D 7F E9 4D BF CF 7A D9 6D DE 22 3F E2 57 DF 50 B0 E3
6E AD 69 4E 05 C8 B5 F7 DC FC 26 0D F8 B7
90 00
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// EAP-TLS Ack
>> A0 80 00 00 06 01 0C 00 06 0D 00
// 6th EAP fragment
<< 02 0C 00 86 0D 40 9A 9E B1 C3 9D 4C 4A C7 17 AB 72 18 80 84
3F 71 4F CA 14 29 78 40 37 FF 10 00 00 82 00 03 00 00 00 00
00 82 00 80 75 0B 3B E0 EC 77 E9 5E A0 4B A9 EE AE 1A B2 50
37 13 3C 5A 93 8B A9 DD C1 9D 0F 50 21 9E 12 34 60 AA 74 BC
AA 36 C7 41 D9 EA DE 25 6C A5 C7 43 F6 87 7A 4D 31 A0 50 D6
B4 B9 F9 4E 6A FF D1 25 9A 62 18 43 54 3F 00 B6 31 21 C1 09
28 9A BB 7B EE F0 62 92 5D E0 A3 9A CA E2
90 00
// EAP-TLS Ack
>> A0 80 00 00 06 01 0D 00 06 0D 00
// 7th EAP fragment
<< 02 0D 00 86 0D 40 51 EE 0A 87 85 36 BD 02 7A 40 B2 86 16 0E
5E CE B5 E8 62 C0 3D F8 BC 2E F9 68 53 75 87 B7 AA 68 C8 EC
65 AD 50 AD 0F 00 00 82 00 04 00 00 00 00 00 82 00 80 5A 35
9C 84 56 48 04 91 2D EE 13 0D CB B1 C0 26 FE A9 37 40 B8 78
A8 C5 06 27 94 2B 5D 04 65 2F 85 22 FB D7 56 04 72 C5 7B B4
2D 41 E9 A9 4E 1D 14 1F F0 8C 83 40 FD 6A 84 39 49 E4 EF D6
D1 8C 4E 7E 22 BD 96 5B 9B 2E 65 04 91 28
90 00
// EAP-TLS Ack
>> A0 80 00 00 06 01 0E 00 06 0D 00
// 8th EAP fragment
<< 02 0E 00 3A 0D 40 FE 91 4E 1A 1A 36 91 F1 05 12 C5 9D 78 11
24 E6 65 44 E9 A2 80 4D F4 61 0C 79 5C 93 D5 B4 F0 29 47 DE
50 91 77 6D 99 62 D8 3E 02 12 2C E0 75 BE A4 4F 1C B9
90 00
// EAP-TLS ack
>> A0 80 00 00 06 01 0F 00 06 0D 00
// 9th and last fragment
<< 02 0F 00 61 0D 00 14 FE FF 00 00 00 00 00 00 00 03 00 01 01
16 FE FF 00 01 00 00 00 00 00 00 00 40 75 D7 8B EB FD 23 6F
F7 63 65 D0 4C 40 1E F2 D5 9F 4D F0 D2 EA DF 6E F0 A8 89 7D
15 86 B4 96 AB 93 61 9B 17 8D 01 50 64 C6 7C 76 BA 90 F7 22
B3 D9 1A E3 B3 DA F4 43 1E 2C 3D 8B 49 02 D7 F6 6F
90 00
DTLS Bridge sends 664 bytes
DTLS Bridge sends 155 bytes
DTLS Bridge sends 155 bytes
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DTLS Bridge sends 14 bytes
DTLS Bridge sends 77 bytes
DTLS Bridge receives
RL-Seq=9, RL-epoch=0
RL-Seq=0, RL-epoch=1
// Flight 6
// ChangeCipherSpec, Finished, in EAP-TLS Request
>> A0 80 00 00 61 01 10 00 61 0D 00 14 FE FF 00 00 00 00 00 00
00 09 00 01 01 16 FE FF 00 01 00 00 00 00 00 00 00 40 3F 2C
D4 FE 86 92 89 66 C7 97 59 F1 C4 B8 15 C4 20 EC 39 FB B5 D5
37 D9 86 72 37 95 DF 88 3A 22 A8 54 98 F0 BD 99 AF AC 37 62
38 0C 86 4A 47 1B C0 63 08 CF 57 1B 5C DC 8C 7B C9 DB FE C0
64 11
// EAP-TLS Ack
<< 02 10 00 06 0D 00
90 00
TLS handshake completion
// Process-EAP-Encrypt type=17h, payload = 16x AA
>> A0 80 00 97 16 01 11 00 16 0D 00 AA AA AA AA AA AA AA AA AA
AA AA AA AA AA AA AA
// Encrypted DTLS Record Layer packet in EAP-Response
<< 02 11 00 57 0D 80 00 00 00 4D 17 FE FF 00 01 00 00 00 00 00
01 00 40 2C E9 45 8E A9 44 FA 2B 13 75 A3 A3 63 01 F5 29 91
8B 20 B1 9B E2 7D 30 2D 91 D1 32 9A 6F 2E 3E D1 7B 64 F0 2A
06 3E C3 5E 34 81 A0 2D 6D C5 30 70 41 83 4A 1C 09 E6 93 66
76 23 45 63 14 3E BB
90 00
Bridge sends 77 bytes
Bridge receives RL-seq=1, RL-epoch=1
//Process-EAP-Decrypt
>> A0 80 00 00 53 01 12 00 53 0D 00 17 FE FF 00 01 00 00 00 00
00 01 00 40 0F 0E EE 3C F7 F4 FF 87 03 22 53 93 53 0D 83 E8
86 A5 F4 36 FB 94 B3 58 B3 A8 86 1A 29 B5 A8 BB 6A EA 8B ED
B9 81 62 A4 96 57 7B 39 8E 55 E5 D1 0E DC 74 49 42 16 27 60
C3 32 ED DA CC D3 42 4A
// DTLS Record Layer Clear Payload = 16x AA
<< 02 12 00 1A 0D 80 00 00 00 10 AA AA AA AA AA AA AA AA AA AA
AA AA AA AA AA AA
90 00
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// Process-EAP-Encrypt type=15h (Alert), payload = 0100
>> A0 80 00 95 08 01 13 00 08 0D 00 01 00
// Encrypted DTLS Record Layer packet in EAP-Response
<< 02 13 00 47 0D 80 00 00 00 3D 15 FE FF 00 01 00 00 00 00 00
02 00 30 76 A5 73 71 9A 69 A3 8F DE 2F 0D 3D 15 49 D5 C1 01
23 AE 0A 0B BB 14 F4 EC 8E 2E 84 A0 76 20 BF 3B 56 E7 C2 B9
A4 0B 13 C2 71 BD AE C4 7F 95 32
90 00
Bridge sends 61 bytes
Bridges receives RL-seq=2, RL-epoch=1
//Process-EAP-Decrypt
>> A0 80 00 00 43 01 14 00 43 0D 00 15 FE FF 00 01 00 00 00 00
00 02 00 30 6B 4A 48 86 92 88 95 3C D9 0D 7B CD 9E 94 7B 93
02 5C 75 FE C1 25 3E 5B 0D 99 8D 13 06 A3 3D 36 12 CD F9 1B
23 0B CE 6E 55 E1 B1 9F 39 18 FA 10
// DTLS Record Layer Clear Payload = 0100
<< 02 14 00 0C 0D 80 00 00 00 02 01 00
90 00
8 Security Considerations
9 IANA Considerations
10 References
10.1 Normative References
[TLS 1.0] Dierks, T., C. Allen, "The TLS Protocol Version 1.0", RFC
2246, January 1999
[TLS 1.1] Dierks, T., Rescorla, E., "The Transport Layer Security
(TLS) Protocol Version 1.1", RFC 4346, April 2006
[DTLS 1.0] E. Rescorla, N. Modadugu, " Datagram Transport Layer
Security", RFC 4347, April 2006
[EAP-TLS] D. Simon, B. Aboba, R. Hurst, "The EAP-TLS Authentication
Protocol", RFC 5216, March 2008
[TLS 1.2] Dierks, T., Rescorla, E., "The Transport Layer Security
(TLS) Protocol Version 1.1", RFC 5746, August 2008
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[DTLS 1.2] E. Rescorla, N. Modadugu "Datagram Transport Layer
Security Version 1.2", RFC 6347, January 2012
[COAP] Z. Shelby, K. Hartke, C. Bormann, "The Constrained
Application Protocol (CoAP)", RFC 7252, June 2014
[ISO7816] ISO 7816, "Cards Identification - Integrated Circuit Cards
with Contacts", The International Organization for Standardization
(ISO)
10.2 Informative References
[EAP SC] Urien, P., "EAP Support in Smartcard", draft-urien-eap-
smartcard-30.txt, December 2016
11 Authors' Addresses
Pascal Urien
Telecom ParisTech
23 avenue d'Italie
75013 Paris Phone: NA
France Email: Pascal.Urien@telecom-paristech.fr
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