draft-ietf-kitten-aes-cts-hmac-sha2-06.txt   draft-ietf-kitten-aes-cts-hmac-sha2-07.txt 
Network Working Group M. Jenkins Network Working Group M. Jenkins
Internet Draft National Security Agency Internet Draft National Security Agency
Intended Status: Informational M. Peck Intended Status: Informational M. Peck
Expires: August 13, 2015 The MITRE Corporation Expires: June 5, 2016 The MITRE Corporation
K. Burgin K. Burgin
February 9, 2015 December 3, 2015
AES Encryption with HMAC-SHA2 for Kerberos 5 AES Encryption with HMAC-SHA2 for Kerberos 5
draft-ietf-kitten-aes-cts-hmac-sha2-06 draft-ietf-kitten-aes-cts-hmac-sha2-07
Abstract Abstract
This document specifies two encryption types and two corresponding This document specifies two encryption types and two corresponding
checksum types for Kerberos 5. The new types use AES in CTS mode checksum types for Kerberos 5. The new types use AES in CTS mode
(CBC mode with ciphertext stealing) for confidentiality and HMAC with (CBC mode with ciphertext stealing) for confidentiality and HMAC with
a SHA-2 hash for integrity. a SHA-2 hash for integrity.
Status of this Memo Status of this Memo
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Internet-Drafts are working documents of the Internet Engineering Internet-Drafts are working documents of the Internet Engineering
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This Internet-Draft will expire on August 13, 2015. This Internet-Draft will expire on June 5, 2016.
Copyright and License Notice Copyright and License Notice
Copyright (c) 2015 IETF Trust and the persons identified as the Copyright (c) 2015 IETF Trust and the persons identified as the
document authors. All rights reserved. document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents Provisions Relating to IETF Documents
(http://trustee.ietf.org/license-info) in effect on the date of (http://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents publication of this document. Please review these documents
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Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Protocol Key Representation . . . . . . . . . . . . . . . . . 3 2. Protocol Key Representation . . . . . . . . . . . . . . . . . 3
3. Key Derivation Function . . . . . . . . . . . . . . . . . . . 3 3. Key Derivation Function . . . . . . . . . . . . . . . . . . . 3
4. Key Generation from Pass Phrases . . . . . . . . . . . . . . . 4 4. Key Generation from Pass Phrases . . . . . . . . . . . . . . . 4
5. Kerberos Algorithm Protocol Parameters . . . . . . . . . . . . 5 5. Kerberos Algorithm Protocol Parameters . . . . . . . . . . . . 5
6. Checksum Parameters . . . . . . . . . . . . . . . . . . . . . 7 6. Checksum Parameters . . . . . . . . . . . . . . . . . . . . . 7
7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 7 7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 7
8. Security Considerations . . . . . . . . . . . . . . . . . . . 8 8. Security Considerations . . . . . . . . . . . . . . . . . . . 7
8.1. Random Values in Salt Strings . . . . . . . . . . . . . . 8 8.1. Random Values in Salt Strings . . . . . . . . . . . . . . 8
8.2. Algorithm Rationale . . . . . . . . . . . . . . . . . . . 9 8.2. Algorithm Rationale . . . . . . . . . . . . . . . . . . . 8
9. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 9 9. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 9
10. References . . . . . . . . . . . . . . . . . . . . . . . . . 9 10. References . . . . . . . . . . . . . . . . . . . . . . . . . 9
10.1. Normative References . . . . . . . . . . . . . . . . . . 9 10.1. Normative References . . . . . . . . . . . . . . . . . . 9
10.2. Informative References . . . . . . . . . . . . . . . . . 9 10.2. Informative References . . . . . . . . . . . . . . . . . 9
Appendix A. Test Vectors . . . . . . . . . . . . . . . . . . . . 10 Appendix A. Test Vectors . . . . . . . . . . . . . . . . . . . . 10
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 16 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 16
1. Introduction 1. Introduction
This document defines two encryption types and two corresponding This document defines two encryption types and two corresponding
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2. Protocol Key Representation 2. Protocol Key Representation
The AES key space is dense, so we can use random or pseudorandom The AES key space is dense, so we can use random or pseudorandom
octet strings directly as keys. The byte representation for the key octet strings directly as keys. The byte representation for the key
is described in [FIPS197], where the first bit of the bit string is is described in [FIPS197], where the first bit of the bit string is
the high bit of the first byte of the byte string (octet string). the high bit of the first byte of the byte string (octet string).
3. Key Derivation Function 3. Key Derivation Function
We use a key derivation function from Section 5.1 of [SP800-108] We use a key derivation function from Section 5.1 of [SP800-108]
which uses the HMAC algorithm as the PRF. All octets are expressed which uses the HMAC algorithm as the PRF.
in big-endian order. The counter i is expressed as four octets and
in this document is always 0x00000001 since there is only a single
iteration of the PRF. The "Label" input to the NIST KDF is the
constant supplied to this key derivation function. When deriving Kc,
Ki, or Ke, the constant is the four octet key usage concatenated with
0x99, 0x55, or 0xAA respectively. When deriving the base-key, the
constant is the ASCII string "kerberos", also known as the byte
string 0x6B65726265726F73. When deriving Kp, the constant is the
ASCII string "prf", also known as the byte string 0x707266. The
"Context" input is omitted. The length of the output key in bits
(denoted as k) is also represented as four octets in big-endian
order. Each application of the KDF only requires a single iteration
of the PRF, so n = 1 in the notation of [SP800-108]. The purposes of
the Kc, Ki, Ke, base-key, and Kp keys are described in Section 5.
In the following summary, | indicates concatenation. The random-to- KDF-HMAC-SHA2(key, label, k) = k-truncate(K1)
key function is the identity function. The k-truncate function is
defined in [RFC3961], Section 5.1.
When the encryption type is aes128-cts-hmac-sha256-128, the output key: The source of entropy from which subsequent keys are derived
key length k is 128 bits for all applications of KDF-HMAC-SHA2(key, (this is known as Ki in [SP800-108]).
constant) which is computed as follows:
K1 = HMAC-SHA-256(key, 00 00 00 01 | constant | 00 | 00 00 00 80) label: An octet string describing the intended usage of the derived
KDF-HMAC-SHA2(key, constant) = random-to-key(k-truncate(K1)) key.
When the encryption type is aes256-cts-hmac-sha384-192, the output k: Length in bits of the key to be outputted, expressed in big-endian
key length k is 256 bits when deriving the base-key (from a binary representation in 4 bytes (this is known as L in [SP800-108]).
passphrase as described in Section 4), Ke, and Kp. The output key (e.g. k = 128 is represented as 0x00000080,
length k is 192 bits when deriving Kc and Ki. KDF-HMAC-SHA2(key, k = 192 as 0x000000C0, k = 256 as 0x00000100,
constant) is computed as follows: k = 384 as 0x00000180)
If deriving Kc or Ki (the constant ends with 0x99 or 0x55): When the encryption type is aes128-cts-hmac-sha256-128, k must be no
k = 192 greater than 256. When the encryption type is aes256-cts-hmac-sha384-
K1 = HMAC-SHA-384(key, 00 00 00 01 | constant | 00 | 00 00 00 C0) 192, k must be no greater than 384.
KDF-HMAC-SHA2(key, constant) = random-to-key(k-truncate(K1))
If deriving the base-key (the constant is "kerberos", the byte The k-truncate function is defined in [RFC3961], Section 5.1.
string 0x6B65726265726F73), Ke (the constant ends with 0xAA),
or Kp (the constant is "prf", the byte string 0x707266): In all computations in this document, | indicates concatenation.
k = 256
K1 = HMAC-SHA-384(key, 00 00 00 01 | constant | 00 | 00 00 01 00) When the encryption type is aes128-cts-hmac-sha256-128, then K1 is
KDF-HMAC-SHA2(key, constant) = random-to-key(k-truncate(K1)) computed as follows:
K1 = HMAC-SHA-256(key, 0x00000001 | label | 0x00 | k)
When the encryption type is aes256-cts-hmac-sha384-192, then K1 is
computed as follows:
K1 = HMAC-SHA-384(key, 0x00000001 | label | 0x00 | k)
4. Key Generation from Pass Phrases 4. Key Generation from Pass Phrases
PBKDF2 [RFC2898] is used to derive the base-key from a passphrase PBKDF2 [RFC2898] is used to derive the base-key from a passphrase and
and salt. salt.
If no string-to-key parameters are specified, the default number of To ensure that different long-term base-keys are used with different
iterations is 32,768. enctypes, we prepend the enctype name to the salt, separated by a
null byte. The enctype-name is "aes128-cts-hmac-sha256-128" or
"aes256-cts-hmac-sha384-192" (without the quotes).
To ensure that different long-term base-keys are used with The user's long-term base-key is derived as follows:
different enctypes, we prepend the enctype name to the salt,
separated by a null byte. The enctype-name is "aes128-cts-hmac-
sha256-128" or "aes256-cts-hmac-sha384-192" (without the quotes).
The user's long-term base-key is derived as follows
iter_count = string-to-key parameter (default is
decimal 32768 if not specified)
saltp = enctype-name | 0x00 | salt saltp = enctype-name | 0x00 | salt
tkey = random-to-key(PBKDF2(passphrase, saltp, tkey = PBKDF2(passphrase, saltp, iter_count, keylength)
iter_count, keylength)) base-key = KDF-HMAC-SHA2(tkey, "kerberos", keylength)
base-key = KDF-HMAC-SHA2(tkey, "kerberos") where "kerberos" is the where "kerberos" is the octet-string
byte string {0x6B65726265726F73}. 0x6B65726265726F73
where the pseudorandom function used by PBKDF2 is HMAC-SHA-256 when where the pseudorandom function used by PBKDF2 is HMAC-SHA-256 when
the enctype is "aes128-cts-hmac-sha256-128" and HMAC-SHA-384 when the the enctype is "aes128-cts-hmac-sha256-128" and HMAC-SHA-384 when the
enctype is "aes256-cts-hmac-sha384-192", the value for keylength is enctype is "aes256-cts-hmac-sha384-192", the value for keylength is
the AES key length (128 or 256 bits), and the algorithm KDF-HMAC-SHA2 the AES key length (128 or 256 bits), and the algorithm KDF-HMAC-SHA2
is defined in Section 3. is defined in Section 3.
5. Kerberos Algorithm Protocol Parameters 5. Kerberos Algorithm Protocol Parameters
The cipherstate is used as the formal initialization vector (IV) The cipherstate is used as the formal initialization vector (IV)
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Ki: the integrity key, inputted into HMAC to provide authenticated Ki: the integrity key, inputted into HMAC to provide authenticated
encryption as defined in "encryption function" and "decryption encryption as defined in "encryption function" and "decryption
function" below. function" below.
required checksum mechanism: as defined in Section 6. required checksum mechanism: as defined in Section 6.
key-generation seed length: key size (128 or 256 bits). key-generation seed length: key size (128 or 256 bits).
string-to-key function: as defined in Section 4. string-to-key function: as defined in Section 4.
default string-to-key parameters: 00 00 80 00. default string-to-key parameters: decimal 32768.
random-to-key function: identity function.
key-derivation function: KDF-HMAC-SHA2 as defined in Section 3. The key-derivation function: KDF-HMAC-SHA2 as defined in Section 3. The
key usage number is expressed as four octets in big-endian order. key usage number is expressed as four octets in big-endian order.
Kc = KDF-HMAC-SHA2(base-key, usage | 0x99) If the enctype is aes128-cts-hmac-sha256-128:
Ke = KDF-HMAC-SHA2(base-key, usage | 0xAA) Kc = KDF-HMAC-SHA2(base-key, usage | 0x99, 128)
Ki = KDF-HMAC-SHA2(base-key, usage | 0x55) Ke = KDF-HMAC-SHA2(base-key, usage | 0xAA, 128)
Ki = KDF-HMAC-SHA2(base-key, usage | 0x55, 128)
If the enctype is aes256-cts-hmac-sha384-192:
Kc = KDF-HMAC-SHA2(base-key, usage | 0x99, 192)
Ke = KDF-HMAC-SHA2(base-key, usage | 0xAA, 256)
Ki = KDF-HMAC-SHA2(base-key, usage | 0x55, 192)
cipherstate: a 128-bit CBC initialization vector derived from cipherstate: a 128-bit CBC initialization vector derived from
the ciphertext. the ciphertext.
initial cipherstate: all bits zero. initial cipherstate: all bits zero.
encryption function: as follows, where E() is AES encryption in encryption function: as follows, where E() is AES encryption in
CBC-CS3 mode, and h is the size of truncated HMAC. CBC-CS3 mode, and h is the size of truncated HMAC (128 bits or
192 bits as described above).
N = random nonce of length 128 bits (the AES block size) N = random nonce of length 128 bits (the AES block size)
IV = cipherstate IV = cipherstate
C = E(Ke, N | plaintext, IV) C = E(Ke, N | plaintext, IV)
H = HMAC(Ki, IV | C) H = HMAC(Ki, IV | C)
ciphertext = C | H[1..h] ciphertext = C | H[1..h]
cipherstate = the last full (128 bit) block of C cipherstate = the last full (128 bit) block of C
(i.e. the next-to-last block if the last block (i.e. the next-to-last block if the last block
is not a full 128 bits) is not a full 128 bits)
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decryption function: as follows, where D() is AES decryption in decryption function: as follows, where D() is AES decryption in
CBC-CS3 mode, and h is the size of truncated HMAC. CBC-CS3 mode, and h is the size of truncated HMAC.
(C, H) = ciphertext (C, H) = ciphertext
IV = cipherstate IV = cipherstate
if H != HMAC(Ki, IV | C)[1..h] if H != HMAC(Ki, IV | C)[1..h]
stop, report error stop, report error
(N, P) = D(Ke, C, IV) (N, P) = D(Ke, C, IV)
Note: N is set to the first block of the decryption output, Note: N is set to the first block of the decryption output,
P is set to the rest of the output. P is set to the rest of the output.
cipherstate = the last full (128 bit) block of C cipherstate = the last full (128 bit) block of C
(i.e. the next-to-last block if the last block (i.e. the next-to-last block if the last block
is not a full 128 bits) is not a full 128 bits)
pseudo-random function: pseudo-random function:
If the enctype is aes128-cts-hmac-sha256-128: If the enctype is aes128-cts-hmac-sha256-128:
k = 128 PRF = KDF-HMAC-SHA2(base-key, "prf" | octet-string, 256)
If the enctype is aes256-cts-hmac-sha384-192: If the enctype is aes256-cts-hmac-sha384-192:
k = 256 PRF = KDF-HMAC-SHA2(base-key, "prf" | octet-string, 384)
Kp = KDF-HMAC-SHA2(base-key, "prf")
PRF = k-truncate(HMAC-SHA2(Kp, octet-string))
where SHA2 is SHA-256 if the enctype is where "prf" is the octet-string 0x707266
aes128-cts-hmac-sha256-128,
and is SHA-384 if the enctype is aes256-cts-hmac-sha384-192.
6. Checksum Parameters 6. Checksum Parameters
The following parameters apply to the checksum types hmac-sha256-128- The following parameters apply to the checksum types hmac-sha256-128-
aes128 and hmac-sha384-192-aes256, which are the associated checksums aes128 and hmac-sha384-192-aes256, which are the associated checksums
for aes128-cts-hmac-sha256-128 and aes256-cts-hmac-sha384-192, for aes128-cts-hmac-sha256-128 and aes256-cts-hmac-sha384-192,
respectively. respectively.
associated cryptosystem: AES-128-CTS or AES-256-CTS as appropriate. associated cryptosystem: AES-128-CTS or AES-256-CTS as appropriate.
get_mic: HMAC(Kc, message)[1..h]. get_mic: HMAC(Kc, message)[1..h].
where h is 128 bits for checksum type hmac-sha256-128-aes128
and 192 bits for checksum type hmac-sha384-192-aes256
verify_mic: get_mic and compare. verify_mic: get_mic and compare.
7. IANA Considerations 7. IANA Considerations
IANA is requested to assign: IANA is requested to assign:
Encryption type numbers for aes128-cts-hmac-sha256-128 and Encryption type numbers for aes128-cts-hmac-sha256-128 and
aes256-cts-hmac-sha384-192 in the Kerberos Encryption Type Numbers aes256-cts-hmac-sha384-192 in the Kerberos Encryption Type Numbers
registry. registry.
Etype encryption type Reference Etype Encryption type Reference
----- --------------- --------- ----- --------------- ---------
TBD1 aes128-cts-hmac-sha256-128 [this document] TBD1 aes128-cts-hmac-sha256-128 [this document]
TBD2 aes256-cts-hmac-sha384-192 [this document] TBD2 aes256-cts-hmac-sha384-192 [this document]
Checksum type numbers for hmac-sha256-128-aes128 and hmac-sha384-192- Checksum type numbers for hmac-sha256-128-aes128 and hmac-sha384-192-
aes256 in the Kerberos Checksum Type Numbers registry. aes256 in the Kerberos Checksum Type Numbers registry.
Sumtype Checksum type Size Reference Sumtype Checksum type Size Reference
------- ------------- ---- --------- ------- ------------- ---- ---------
TBD3 hmac-sha256-128-aes128 16 [this document] TBD3 hmac-sha256-128-aes128 16 [this document]
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password at two KDCs to get the same keys. If each KDC uses a random password at two KDCs to get the same keys. If each KDC uses a random
salt, they won't have the same keys. salt, they won't have the same keys.
* Random salts may interfere with password history checking. * Random salts may interfere with password history checking.
* ktutil's add_entry command assumes the default salt. * ktutil's add_entry command assumes the default salt.
8.2. Algorithm Rationale 8.2. Algorithm Rationale
This document has been written to be consistent with common This document has been written to be consistent with common
implementations of AES and SHA-2. The encryption and hash algorithm implementations of AES and SHA-2. The encryption and hash algorithm
sizes have been chosen to create a consistent level of protection, sizes have been chosen to create a consistent level of protection,
with consideration to implementation efficiencies. So, for instance, with consideration to implementation efficiencies. So, for instance,
SHA-384, which would normally be matched to AES-192, is instead SHA-384, which would normally be matched to AES-192, is instead
matched to AES-256 to leverage the fact that there are efficient matched to AES-256 to leverage the fact that there are efficient
hardware implementations of AES-256. Note that, as indicated by the hardware implementations of AES-256. Note that, as indicated by the
enc-type name "aes256-cts-hmac-sha384-192", the use of SHA-384 and enc-type name "aes256-cts-hmac-sha384-192", the truncation of the
AES-256 with a 192-bit key provides only a 192-bit level of security. HMAC-SHA-384 output to 192-bits results in an overall 192-bit level
of security.
9. Acknowledgements 9. Acknowledgements
Kelley Burgin was employed at the National Security Agency during Kelley Burgin was employed at the National Security Agency during
much of the work on this document. much of the work on this document.
10. References 10. References
10.1. Normative References 10.1. Normative References
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45 BD 80 6D BF 6A 83 3A 9C FF C1 C9 45 89 A2 22 45 BD 80 6D BF 6A 83 3A 9C FF C1 C9 45 89 A2 22
36 7A 79 BC 21 C4 13 71 89 06 E9 F5 78 A7 84 67 36 7A 79 BC 21 C4 13 71 89 06 E9 F5 78 A7 84 67
Sample results for key derivation: Sample results for key derivation:
---------------------------------- ----------------------------------
enctype aes128-cts-hmac-sha256-128: enctype aes128-cts-hmac-sha256-128:
128-bit base-key: 128-bit base-key:
37 05 D9 60 80 C1 77 28 A0 E8 00 EA B6 E0 D2 3C 37 05 D9 60 80 C1 77 28 A0 E8 00 EA B6 E0 D2 3C
Kc value for key usage 2 (constant = 0x0000000299): Kc value for key usage 2 (constant = 0x0000000299):
B3 1A 01 8A 48 F5 47 76 F4 03 E9 A3 96 32 5D C3 B3 1A 01 8A 48 F5 47 76 F4 03 E9 A3 96 32 5D C3
Ke value for key usage 2 (constant = 0x00000002AA): Ke value for key usage 2 (constant = 0x00000002AA):
9B 19 7D D1 E8 C5 60 9D 6E 67 C3 E3 7C 62 C7 2E 9B 19 7D D1 E8 C5 60 9D 6E 67 C3 E3 7C 62 C7 2E
Ki value for key usage 2 (constant = 0x0000000255): Ki value for key usage 2 (constant = 0x0000000255):
9F DA 0E 56 AB 2D 85 E1 56 9A 68 86 96 C2 6A 6C 9F DA 0E 56 AB 2D 85 E1 56 9A 68 86 96 C2 6A 6C
Kp value (constant = 0x707266):
9C 66 77 98 08 4F 16 82 1E 77 15 DD 5A A6 EB 71
enctype aes256-cts-hmac-sha384-192: enctype aes256-cts-hmac-sha384-192:
256-bit base-key: 256-bit base-key:
6D 40 4D 37 FA F7 9F 9D F0 D3 35 68 D3 20 66 98 6D 40 4D 37 FA F7 9F 9D F0 D3 35 68 D3 20 66 98
00 EB 48 36 47 2E A8 A0 26 D1 6B 71 82 46 0C 52 00 EB 48 36 47 2E A8 A0 26 D1 6B 71 82 46 0C 52
Kc value for key usage 2 (constant = 0x0000000299): Kc value for key usage 2 (constant = 0x0000000299):
EF 57 18 BE 86 CC 84 96 3D 8B BB 50 31 E9 F5 C4 EF 57 18 BE 86 CC 84 96 3D 8B BB 50 31 E9 F5 C4
BA 41 F2 8F AF 69 E7 3D BA 41 F2 8F AF 69 E7 3D
Ke value for key usage 2 (constant = 0x00000002AA): Ke value for key usage 2 (constant = 0x00000002AA):
56 AB 22 BE E6 3D 82 D7 BC 52 27 F6 77 3F 8E A7 56 AB 22 BE E6 3D 82 D7 BC 52 27 F6 77 3F 8E A7
A5 EB 1C 82 51 60 C3 83 12 98 0C 44 2E 5C 7E 49 A5 EB 1C 82 51 60 C3 83 12 98 0C 44 2E 5C 7E 49
Ki value for key usage 2 (constant = 0x0000000255): Ki value for key usage 2 (constant = 0x0000000255):
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00 EB 48 36 47 2E A8 A0 26 D1 6B 71 82 46 0C 52 00 EB 48 36 47 2E A8 A0 26 D1 6B 71 82 46 0C 52
Kc value for key usage 2 (constant = 0x0000000299): Kc value for key usage 2 (constant = 0x0000000299):
EF 57 18 BE 86 CC 84 96 3D 8B BB 50 31 E9 F5 C4 EF 57 18 BE 86 CC 84 96 3D 8B BB 50 31 E9 F5 C4
BA 41 F2 8F AF 69 E7 3D BA 41 F2 8F AF 69 E7 3D
Ke value for key usage 2 (constant = 0x00000002AA): Ke value for key usage 2 (constant = 0x00000002AA):
56 AB 22 BE E6 3D 82 D7 BC 52 27 F6 77 3F 8E A7 56 AB 22 BE E6 3D 82 D7 BC 52 27 F6 77 3F 8E A7
A5 EB 1C 82 51 60 C3 83 12 98 0C 44 2E 5C 7E 49 A5 EB 1C 82 51 60 C3 83 12 98 0C 44 2E 5C 7E 49
Ki value for key usage 2 (constant = 0x0000000255): Ki value for key usage 2 (constant = 0x0000000255):
69 B1 65 14 E3 CD 8E 56 B8 20 10 D5 C7 30 12 B6 69 B1 65 14 E3 CD 8E 56 B8 20 10 D5 C7 30 12 B6
22 C4 D0 0F FC 23 ED 1F 22 C4 D0 0F FC 23 ED 1F
Kp value (constant = 0x707266):
5D 63 0D B7 EF DE 37 DE 9C 92 03 C5 2B D9 6C 77
31 BE 1C 5B DD 50 DC 75 44 D9 60 AF F3 CC 23 04
Sample pseudorandom function (PRF) invocations:
----------------------------------------
PRF input octet-string: "test" (0x74657374)
enctype aes128-cts-hmac-sha256-128:
Kp value:
9C 66 77 98 08 4F 16 82 1E 77 15 DD 5A A6 EB 71
PRF output:
3A CA 18 6C C1 26 56 76 5C FE B1 D2 2D 1C B1 36
enctype aes256-cts-hmac-sha384-192:
Kp value:
5D 63 0D B7 EF DE 37 DE 9C 92 03 C5 2B D9 6C 77
31 BE 1C 5B DD 50 DC 75 44 D9 60 AF F3 CC 23 04
PRF output:
01 72 03 F2 90 CD 16 6C D6 B2 BB 4F 18 7D 16 23
6B 9A 4E D7 66 19 D8 11 6C 64 06 A3 37 E7 F9 08
Sample encryptions (all using the default cipher state): Sample encryptions (all using the default cipher state):
-------------------------------------------------------- --------------------------------------------------------
These sample encryptions use the above sample key
derivation results, including use of the same
base-key and key usage values.
The following test vectors are for The following test vectors are for
enctype aes128-cts-hmac-sha256-128: enctype aes128-cts-hmac-sha256-128:
Plaintext: (empty) Plaintext: (empty)
Confounder: Confounder:
7E 58 95 EA F2 67 24 35 BA D8 17 F5 45 A3 71 48 7E 58 95 EA F2 67 24 35 BA D8 17 F5 45 A3 71 48
128-bit AES key: 128-bit AES key (Ke):
9B 19 7D D1 E8 C5 60 9D 6E 67 C3 E3 7C 62 C7 2E 9B 19 7D D1 E8 C5 60 9D 6E 67 C3 E3 7C 62 C7 2E
128-bit HMAC key: 128-bit HMAC key (Ki):
9F DA 0E 56 AB 2D 85 E1 56 9A 68 86 96 C2 6A 6C 9F DA 0E 56 AB 2D 85 E1 56 9A 68 86 96 C2 6A 6C
AES Output: AES Output:
EF 85 FB 89 0B B8 47 2F 4D AB 20 39 4D CA 78 1D EF 85 FB 89 0B B8 47 2F 4D AB 20 39 4D CA 78 1D
Truncated HMAC Output: Truncated HMAC Output:
AD 87 7E DA 39 D5 0C 87 0C 0D 5A 0A 8E 48 C7 18 AD 87 7E DA 39 D5 0C 87 0C 0D 5A 0A 8E 48 C7 18
Ciphertext (AES Output | HMAC Output): Ciphertext (AES Output | HMAC Output):
EF 85 FB 89 0B B8 47 2F 4D AB 20 39 4D CA 78 1D EF 85 FB 89 0B B8 47 2F 4D AB 20 39 4D CA 78 1D
AD 87 7E DA 39 D5 0C 87 0C 0D 5A 0A 8E 48 C7 18 AD 87 7E DA 39 D5 0C 87 0C 0D 5A 0A 8E 48 C7 18
Plaintext: (length less than block size) Plaintext: (length less than block size)
00 01 02 03 04 05 00 01 02 03 04 05
Confounder: Confounder:
7B CA 28 5E 2F D4 13 0F B5 5B 1A 5C 83 BC 5B 24 7B CA 28 5E 2F D4 13 0F B5 5B 1A 5C 83 BC 5B 24
128-bit AES key: 128-bit AES key (Ke):
4E FD A6 52 4E 6B 56 B4 F2 12 61 FB FC 93 21 AB 9B 19 7D D1 E8 C5 60 9D 6E 67 C3 E3 7C 62 C7 2E
128-bit HMAC key: 128-bit HMAC key (Ki):
29 1B 0C 37 73 D7 6E E6 BA 2C CF 1E 03 93 F6 3E 9F DA 0E 56 AB 2D 85 E1 56 9A 68 86 96 C2 6A 6C
AES Output: AES Output:
AB 70 F4 BA 9D 76 55 AF 24 B5 76 E4 6E FB 7A 98 84 D7 F3 07 54 ED 98 7B AB 0B F3 50 6B EB 09 CF
F1 4B 93 65 9D 1B B5 54 02 CE F7 E6
Truncated HMAC Output: Truncated HMAC Output:
A0 C5 F4 7C AA 84 42 19 F9 08 AD ED EF 52 5B 71 87 7C E9 9E 24 7E 52 D1 6E D4 42 1D FD F8 97 6C
Ciphertext: Ciphertext:
AB 70 F4 BA 9D 76 55 AF 24 B5 76 E4 6E FB 7A 98 84 D7 F3 07 54 ED 98 7B AB 0B F3 50 6B EB 09 CF
F1 4B 93 65 9D 1B A0 C5 F4 7C AA 84 42 19 F9 08 B5 54 02 CE F7 E6 87 7C E9 9E 24 7E 52 D1 6E D4
AD ED EF 52 5B 71 42 1D FD F8 97 6C
Plaintext: (length equals block size) Plaintext: (length equals block size)
00 01 02 03 04 05 06 07 08 09 0A 0B 0C 0D 0E 0F 00 01 02 03 04 05 06 07 08 09 0A 0B 0C 0D 0E 0F
Confounder: Confounder:
56 AB 21 71 3F F6 2C 0A 14 57 20 0F 6F A9 94 8F 56 AB 21 71 3F F6 2C 0A 14 57 20 0F 6F A9 94 8F
128-bit AES key: 128-bit AES key (Ke):
FF 82 40 42 4B CC BA 05 56 50 C0 39 3B 83 DF 3B 9B 19 7D D1 E8 C5 60 9D 6E 67 C3 E3 7C 62 C7 2E
128-bit HMAC key: 128-bit HMAC key (Ki):
ED 15 62 8B 45 35 8C BF 7F 50 E7 64 C2 6B 8A 1A 9F DA 0E 56 AB 2D 85 E1 56 9A 68 86 96 C2 6A 6C
AES Output: AES Output:
E7 34 8E 74 86 E5 A7 87 0F 51 2E 65 CA C8 65 75 35 17 D6 40 F5 0D DC 8A D3 62 87 22 B3 56 9D 2A
78 26 FF C0 EA 5B 28 A8 B9 60 8B B3 08 CD E2 CC E0 74 93 FA 82 63 25 40 80 EA 65 C1 00 8E 8F C2
Truncated HMAC Output: Truncated HMAC Output:
C1 85 4E F2 F3 4D 02 35 4E C7 AA 53 BE 03 BE D5 95 FB 48 52 E7 D8 3E 1E 7C 48 C3 7E EB E6 B0 D3
Ciphertext: Ciphertext:
E7 34 8E 74 86 E5 A7 87 0F 51 2E 65 CA C8 65 75 35 17 D6 40 F5 0D DC 8A D3 62 87 22 B3 56 9D 2A
78 26 FF C0 EA 5B 28 A8 B9 60 8B B3 08 CD E2 CC E0 74 93 FA 82 63 25 40 80 EA 65 C1 00 8E 8F C2
C1 85 4E F2 F3 4D 02 35 4E C7 AA 53 BE 03 BE D5 95 FB 48 52 E7 D8 3E 1E 7C 48 C3 7E EB E6 B0 D3
Plaintext: (length greater than block size) Plaintext: (length greater than block size)
00 01 02 03 04 05 06 07 08 09 0A 0B 0C 0D 0E 0F 00 01 02 03 04 05 06 07 08 09 0A 0B 0C 0D 0E 0F
10 11 12 13 14 10 11 12 13 14
Confounder: Confounder:
A7 A4 E2 9A 47 28 CE 10 66 4F B6 4E 49 AD 3F AC A7 A4 E2 9A 47 28 CE 10 66 4F B6 4E 49 AD 3F AC
128-bit AES key: 128-bit AES key (Ke):
B5 9B 88 75 AD 5D CA FF F7 79 4D 93 F8 19 9D 79 9B 19 7D D1 E8 C5 60 9D 6E 67 C3 E3 7C 62 C7 2E
128-bit HMAC key: 128-bit HMAC key (Ki):
0A 42 1D 72 2F 8F C2 D6 84 8B 1C DA D1 5A 49 C9 9F DA 0E 56 AB 2D 85 E1 56 9A 68 86 96 C2 6A 6C
AES Output: AES Output:
C3 53 72 86 FF 9C FE 49 8D 2E FC FC 99 6D AC 2D 72 0F 73 B1 8D 98 59 CD 6C CB 43 46 11 5C D3 36
52 CA 56 03 B3 E8 68 EA 1E 9C 54 E8 2A E5 CE 7A C7 0F 58 ED C0 C4 43 7C 55 73 54 4C 31 C8 13 BC
79 3E 21 09 7D E1 E6 D0 72 C1
Truncated HMAC Output: Truncated HMAC Output:
5B 03 5D 78 A7 E9 84 75 EC 91 0C E3 7A A0 2A 7D 86 B3 9A 41 3C 2F 92 CA 9B 83 34 A2 87 FF CB FC
Ciphertext: Ciphertext:
C3 53 72 86 FF 9C FE 49 8D 2E FC FC 99 6D AC 2D 72 0F 73 B1 8D 98 59 CD 6C CB 43 46 11 5C D3 36
52 CA 56 03 B3 E8 68 EA 1E 9C 54 E8 2A E5 CE 7A C7 0F 58 ED C0 C4 43 7C 55 73 54 4C 31 C8 13 BC
79 3E 21 09 7D 5B 03 5D 78 A7 E9 84 75 EC 91 0C E1 E6 D0 72 C1 86 B3 9A 41 3C 2F 92 CA 9B 83 34
E3 7A A0 2A 7D A2 87 FF CB FC
The following test vectors are for enctype The following test vectors are for enctype
aes256-cts-hmac-sha384-192: aes256-cts-hmac-sha384-192:
Plaintext: (empty) Plaintext: (empty)
Confounder: Confounder:
F7 64 E9 FA 15 C2 76 47 8B 2C 7D 0C 4E 5F 58 E4 F7 64 E9 FA 15 C2 76 47 8B 2C 7D 0C 4E 5F 58 E4
256-bit AES key: 256-bit AES key (Ke):
0F A2 0D 7D 03 33 EE 65 16 2C DA 67 E7 AD 0D 3C 56 AB 22 BE E6 3D 82 D7 BC 52 27 F6 77 3F 8E A7
5E 03 1F 3B 66 70 E0 31 28 2F AC C2 87 9C 21 C7 A5 EB 1C 82 51 60 C3 83 12 98 0C 44 2E 5C 7E 49
192-bit HMAC key: 192-bit HMAC key (Ki):
53 BF 30 6A 68 33 A3 25 18 FC B8 5F 63 1D 03 D5 69 B1 65 14 E3 CD 8E 56 B8 20 10 D5 C7 30 12 B6
2E E3 1B 39 75 2F 57 ED 22 C4 D0 0F FC 23 ED 1F
AES Output: AES Output:
FE 6A 55 14 F3 99 7C 8C AA F2 2D 8E EE 28 6D 7D 41 F5 3F A5 BF E7 02 6D 91 FA F9 BE 95 91 95 A0
Truncated HMAC Output: Truncated HMAC Output:
81 1E AD AE DA 7F B9 75 AD 96 C0 07 5A 98 83 F9 58 70 72 73 A9 6A 40 F0 A0 19 60 62 1A C6 12 74
AC 3A AB 06 97 FC E8 5A 8B 9B BF BE 7E B4 CE 3C
Ciphertext: Ciphertext:
FE 6A 55 14 F3 99 7C 8C AA F2 2D 8E EE 28 6D 7D 41 F5 3F A5 BF E7 02 6D 91 FA F9 BE 95 91 95 A0
81 1E AD AE DA 7F B9 75 AD 96 C0 07 5A 98 83 F9 58 70 72 73 A9 6A 40 F0 A0 19 60 62 1A C6 12 74
AC 3A AB 06 97 FC E8 5A 8B 9B BF BE 7E B4 CE 3C
Plaintext: (length less than block size) Plaintext: (length less than block size)
00 01 02 03 04 05 00 01 02 03 04 05
Confounder: Confounder:
B8 0D 32 51 C1 F6 47 14 94 25 6F FE 71 2D 0B 9A B8 0D 32 51 C1 F6 47 14 94 25 6F FE 71 2D 0B 9A
256-bit AES key: 256-bit AES key (Ke):
47 DA 4C A2 8B D1 C1 14 D5 50 7E 55 81 86 CA 4F 56 AB 22 BE E6 3D 82 D7 BC 52 27 F6 77 3F 8E A7
DB A0 DA E5 B2 4F 6D 68 89 D5 3A FB F1 D0 B8 36 A5 EB 1C 82 51 60 C3 83 12 98 0C 44 2E 5C 7E 49
192-bit HMAC key: 192-bit HMAC key (Ki):
13 6B 5C 83 C9 53 AE 29 E2 C2 31 6A 7B 34 B8 C2 69 B1 65 14 E3 CD 8E 56 B8 20 10 D5 C7 30 12 B6
AD 26 E4 66 7F AB 42 6E 22 C4 D0 0F FC 23 ED 1F
AES Output: AES Output:
14 78 CF 26 BA 5E 7D 3A 9D C7 99 7A 80 10 76 2C 4E D7 B3 7C 2B CA C8 F7 4F 23 C1 CF 07 E6 2B C7
74 3B D4 BC 22 EC B7 5F B3 F6 37 B9
Truncated HMAC Output: Truncated HMAC Output:
17 2A B2 BB 12 B0 0D BE C2 BF E6 29 CF DD 62 EC F5 59 C7 F6 64 F6 9E AB 7B 60 92 23 75 26 EA 0D
3E 45 83 8F A9 FB AE 6E 1F 61 CB 20 D6 9D 10 F2
Ciphertext: Ciphertext:
14 78 CF 26 BA 5E 7D 3A 9D C7 99 7A 80 10 76 2C 4E D7 B3 7C 2B CA C8 F7 4F 23 C1 CF 07 E6 2B C7
74 3B D4 BC 22 EC 17 2A B2 BB 12 B0 0D BE C2 BF B7 5F B3 F6 37 B9 F5 59 C7 F6 64 F6 9E AB 7B 60
E6 29 CF DD 62 EC 3E 45 83 8F A9 FB AE 6E 92 23 75 26 EA 0D 1F 61 CB 20 D6 9D 10 F2
Plaintext: (length equals block size) Plaintext: (length equals block size)
00 01 02 03 04 05 06 07 08 09 0A 0B 0C 0D 0E 0F 00 01 02 03 04 05 06 07 08 09 0A 0B 0C 0D 0E 0F
Confounder: Confounder:
53 BF 8A 0D 10 52 65 D4 E2 76 42 86 24 CE 5E 63 53 BF 8A 0D 10 52 65 D4 E2 76 42 86 24 CE 5E 63
256-bit AES key: 256-bit AES key (Ke):
5E A6 16 D8 FD A2 33 F1 B4 99 79 A4 B9 FA 01 D3 56 AB 22 BE E6 3D 82 D7 BC 52 27 F6 77 3F 8E A7
21 B1 3D 6F BD 6E 3B B7 2E 54 B4 85 E2 36 AF 23 A5 EB 1C 82 51 60 C3 83 12 98 0C 44 2E 5C 7E 49
192-bit HMAC key: 192-bit HMAC key (Ki):
AD D3 8D C9 86 83 C5 CC 14 E3 C7 37 EA A7 06 47
B3 19 71 0E 87 6A 38 77 69 B1 65 14 E3 CD 8E 56 B8 20 10 D5 C7 30 12 B6
22 C4 D0 0F FC 23 ED 1F
AES Output: AES Output:
B6 0B 6A A6 00 C2 D8 4B 03 A6 1C 18 DD A7 05 F0 BC 47 FF EC 79 98 EB 91 E8 11 5C F8 D1 9D AC 4B
FE 90 B9 36 B8 8C 4F EA 06 D7 1A 99 35 75 28 60 BB E2 E1 63 E8 7D D3 7F 49 BE CA 92 02 77 64 F6
Truncated HMAC Output: Truncated HMAC Output:
2F E5 BD 6E 41 78 17 D6 2A D2 C9 CF 50 8D FA E1 8C F5 1F 14 D7 98 C2 27 3F 35 DF 57 4D 1F 93 2E
B3 C9 6F 4B 45 C1 9B 77 40 C4 FF 25 5B 36 A2 66
Ciphertext: Ciphertext:
B6 0B 6A A6 00 C2 D8 4B 03 A6 1C 18 DD A7 05 F0 BC 47 FF EC 79 98 EB 91 E8 11 5C F8 D1 9D AC 4B
FE 90 B9 36 B8 8C 4F EA 06 D7 1A 99 35 75 28 60 BB E2 E1 63 E8 7D D3 7F 49 BE CA 92 02 77 64 F6
2F E5 BD 6E 41 78 17 D6 2A D2 C9 CF 50 8D FA E1 8C F5 1F 14 D7 98 C2 27 3F 35 DF 57 4D 1F 93 2E
B3 C9 6F 4B 45 C1 9B 77 40 C4 FF 25 5B 36 A2 66
Plaintext: (length greater than block size) Plaintext: (length greater than block size)
00 01 02 03 04 05 06 07 08 09 0A 0B 0C 0D 0E 0F 00 01 02 03 04 05 06 07 08 09 0A 0B 0C 0D 0E 0F
10 11 12 13 14 10 11 12 13 14
Confounder: Confounder:
76 3E 65 36 7E 86 4F 02 F5 51 53 C7 E3 B5 8A F1 76 3E 65 36 7E 86 4F 02 F5 51 53 C7 E3 B5 8A F1
256-bit AES key (Ke):
256-bit AES key: 56 AB 22 BE E6 3D 82 D7 BC 52 27 F6 77 3F 8E A7
B3 A8 02 E3 40 61 3E F1 E0 EC E9 1A 15 7C 59 12 A5 EB 1C 82 51 60 C3 83 12 98 0C 44 2E 5C 7E 49
6F BD C4 B8 C2 4C 8D 0B 2E 5A 30 F0 1E 7E 34 88 192-bit HMAC key (Ki):
192-bit HMAC key: 69 B1 65 14 E3 CD 8E 56 B8 20 10 D5 C7 30 12 B6
FC 0B 49 9B 83 55 A3 2A C3 C9 AC B6 64 93 63 EB 22 C4 D0 0F FC 23 ED 1F
5D BB A4 25 1A 75 B2 0A
AES Output: AES Output:
4C F9 8B 5E DA 0D 94 9F B3 8E CD 67 DE 80 0F 79 40 01 3E 2D F5 8E 87 51 95 7D 28 78 BC D2 D6 FE
46 19 F9 EA CB 30 54 33 50 6B 9A D4 48 4B D9 5B 10 1C CF D5 56 CB 1E AE 79 DB 3C 3E E8 64 29 F2
E0 55 F5 69 EB B2 A6 02 AC 86
Truncated HMAC Output: Truncated HMAC Output:
7C F8 36 70 75 8C BF DA 31 3C FE F8 74 2B 11 74 FE F6 EC B6 47 D6 29 5F AE 07 7A 1F EB 51 75 08
14 A7 DD 12 B4 96 64 2E D2 C1 6B 41 92 E0 1F 62
Ciphertext: Ciphertext:
4C F9 8B 5E DA 0D 94 9F B3 8E CD 67 DE 80 0F 79 40 01 3E 2D F5 8E 87 51 95 7D 28 78 BC D2 D6 FE
46 19 F9 EA CB 30 54 33 50 6B 9A D4 48 4B D9 5B 10 1C CF D5 56 CB 1E AE 79 DB 3C 3E E8 64 29 F2
E0 55 F5 69 EB 7C F8 36 70 75 8C BF DA 31 3C FE B2 A6 02 AC 86 FE F6 EC B6 47 D6 29 5F AE 07 7A
F8 74 2B 11 74 14 A7 DD 12 B4 96 64 2E 1F EB 51 75 08 D2 C1 6B 41 92 E0 1F 62
Sample checksums: Sample checksums:
----------------- -----------------
These sample checksums use the above sample key
derivation results, including use of the same
base-key and key usage values.
Checksum type: hmac-sha256-128-aes128 Checksum type: hmac-sha256-128-aes128
128-bit HMAC key: 128-bit HMAC key (Kc):
B3 1A 01 8A 48 F5 47 76 F4 03 E9 A3 96 32 5D C3 B3 1A 01 8A 48 F5 47 76 F4 03 E9 A3 96 32 5D C3
Plaintext: Plaintext:
00 01 02 03 04 05 06 07 08 09 0A 0B 0C 0D 0E 0F 00 01 02 03 04 05 06 07 08 09 0A 0B 0C 0D 0E 0F
10 11 12 13 14 10 11 12 13 14
Checksum: Checksum:
D7 83 67 18 66 43 D6 7B 41 1C BA 91 39 FC 1D EE D7 83 67 18 66 43 D6 7B 41 1C BA 91 39 FC 1D EE
Checksum type: hmac-sha384-192-aes256 Checksum type: hmac-sha384-192-aes256
192-bit HMAC key: 192-bit HMAC key (Kc):
EF 57 18 BE 86 CC 84 96 3D 8B BB 50 31 E9 F5 C4 EF 57 18 BE 86 CC 84 96 3D 8B BB 50 31 E9 F5 C4
BA 41 F2 8F AF 69 E7 3D BA 41 F2 8F AF 69 E7 3D
Plaintext: Plaintext:
00 01 02 03 04 05 06 07 08 09 0A 0B 0C 0D 0E 0F 00 01 02 03 04 05 06 07 08 09 0A 0B 0C 0D 0E 0F
10 11 12 13 14 10 11 12 13 14
Checksum: Checksum:
45 EE 79 15 67 EE FC A3 7F 4A C1 E0 22 2D E8 0D 45 EE 79 15 67 EE FC A3 7F 4A C1 E0 22 2D E8 0D
43 C3 BF A0 66 99 67 2A 43 C3 BF A0 66 99 67 2A
Sample pseudorandom function (PRF) invocations:
----------------------------------------
PRF input octet-string: "test" (0x74657374)
enctype aes128-cts-hmac-sha256-128:
base-key value / HMAC-SHA-256 key:
37 05 D9 60 80 C1 77 28 A0 E8 00 EA B6 E0 D2 3C
HMAC-SHA-256 input message:
00 00 00 01 70 72 66 74 65 73 74 00 00 00 01 00
PRF output:
14 11 15 B0 A6 CB 9A 1D CB B4 C7 E2 5B 43 32 22
52 DE 58 11 21 85 C5 DC F5 12 5E 7B 81 54 8D 39
enctype aes256-cts-hmac-sha384-192:
base-key value / HMAC-SHA-384 key:
6D 40 4D 37 FA F7 9F 9D F0 D3 35 68 D3 20 66 98
00 EB 48 36 47 2E A8 A0 26 D1 6B 71 82 46 0C 52
HMAC-SHA-384 input message:
00 00 00 01 70 72 66 74 65 73 74 00 00 00 01 80
PRF output:
31 0A 4B 5C D2 90 F7 04 33 B2 A1 A1 D0 93 FD F7
8C 6C 9D AE 5C AC D3 A7 BD 45 CB 67 44 41 99 43
0D 36 19 06 44 E8 A2 16 66 43 AE AD E9 63 87 52
Authors' Addresses Authors' Addresses
Michael J. Jenkins Michael J. Jenkins
National Security Agency National Security Agency
EMail: mjjenki@tycho.ncsc.mil EMail: mjjenki@tycho.ncsc.mil
Michael A. Peck Michael A. Peck
The MITRE Corporation The MITRE Corporation
 End of changes. 70 change blocks. 
194 lines changed or deleted 194 lines changed or added

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