< draft-burgin-kerberos-aes-cbc-hmac-sha2-01.txt		draft-burgin-kerberos-aes-cbc-hmac-sha2-02.txt >
	Network Working Group K.W. Burgin		Network Working Group K. Burgin
	Internet Draft National Security Agency		Internet Draft National Security Agency
	Intended Status: Standards Track M.A. Peck		Intended Status: Informational M. Peck
	Expires: January 12, 2012 The MITRE Corporation		Expires: April 22, 2013 The MITRE Corporation
	July 11, 2011		October 19, 2012
	AES-CBC Mode with HMAC-SHA2 For Kerberos 5		AES Encryption with HMAC-SHA2 for Kerberos 5
	draft-burgin-kerberos-aes-cbc-hmac-sha2-01		draft-burgin-kerberos-aes-cbc-hmac-sha2-02
	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 CBC mode		checksum types for Kerberos 5. The new types use AES in CBC mode
	with PKCS#5 padding for confidentiality and HMAC with a SHA-2 hash		with ciphertext stealing for confidentiality and HMAC with a SHA-2
	for integrity.		hash for integrity.
	Status of this Memo		Status of this Memo
	This Internet-Draft is submitted in full conformance with the		This Internet-Draft is submitted in full conformance with the
	provisions of BCP 78 and BCP 79.		provisions of BCP 78 and BCP 79.
	Internet-Drafts are working documents of the Internet Engineering		Internet-Drafts are working documents of the Internet Engineering
	Task Force (IETF). Note that other groups may also distribute		Task Force (IETF). Note that other groups may also distribute
	working documents as Internet-Drafts. The list of current Internet-		working documents as Internet-Drafts. The list of current Internet-
	Drafts is at http://datatracker.ietf.org/drafts/current/.		Drafts is at http://datatracker.ietf.org/drafts/current/.
	Internet-Drafts are draft documents valid for a maximum of six months		Internet-Drafts are draft documents valid for a maximum of six months
	and may be updated, replaced, or obsoleted by other documents at any		and may be updated, replaced, or obsoleted by other documents at any
	time. It is inappropriate to use Internet-Drafts as reference		time. It is inappropriate to use Internet-Drafts as reference
	material or to cite them other than as "work in progress."		material or to cite them other than as "work in progress."
	This Internet-Draft will expire on January 12, 2012.		This Internet-Draft will expire on February 21, 2013.
	Copyright and License Notice		Copyright and License Notice
	Copyright (c) 2011 IETF Trust and the persons identified as the		Copyright (c) 2012 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
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	carefully, as they describe your rights and restrictions with respect		carefully, as they describe your rights and restrictions with respect
	to this document. Code Components extracted from this document must		to this document. Code Components extracted from this document must
	include Simplified BSD License text as described in Section 4.e of		include Simplified BSD License text as described in Section 4.e of
	the Trust Legal Provisions and are provided without warranty as		the Trust Legal Provisions and are provided without warranty as
	described in the Simplified BSD License.		described in the Simplified BSD License.
	Table of Contents		Table of Contents
	1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3		1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
	2. Conventions used in this Document . . . . . . . . . . . . . . 3		2. Conventions used in this Document . . . . . . . . . . . . . . 3
	3. Protocol Key Representation . . . . . . . . . . . . . . . . . 3		3. Protocol Key Representation . . . . . . . . . . . . . . . . . 3
	4. Key Generation from Pass Phrases . . . . . . . . . . . . . . . 3		4. Key Generation from Pass Phrases . . . . . . . . . . . . . . . 3
	5. Key Derivation Function . . . . . . . . . . . . . . . . . . . 4		5. Key Derivation Function . . . . . . . . . . . . . . . . . . . 4
	6. Kerberos Algorithm Protocol Parameters . . . . . . . . . . . . 5		6. Kerberos Algorithm Protocol Parameters . . . . . . . . . . . . 5
	7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 7		7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 7
	8. Security Considerations . . . . . . . . . . . . . . . . . . . 8		8. Security Considerations . . . . . . . . . . . . . . . . . . . 8
	9 References . . . . . . . . . . . . . . . . . . . . . . . . . . 8		9. References . . . . . . . . . . . . . . . . . . . . . . . . . . 8
	9.1 Normative References . . . . . . . . . . . . . . . . . . . 8		9.1. Normative References . . . . . . . . . . . . . . . . . . . 8
	9.2 Informative References . . . . . . . . . . . . . . . . . . 9		9.2. Informative References . . . . . . . . . . . . . . . . . . 9
	Appendix A. AES-CBC Test Vectors . . . . . . . . . . . . . . . . 9		Appendix A. AES-CBC Test Vectors . . . . . . . . . . . . . . . . 9
	Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 9		Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 9
	1 Introduction		1. Introduction
	This document defines two encryption types and two corresponding		This document defines two encryption types and two corresponding
	checksum types for Kerberos 5 using AES with 128-bit or 256-bit keys.		checksum types for Kerberos 5 using AES with 128-bit or 256-bit keys.
	The new types conform to the framework specified in [RFC3961], but		The new types conform to the framework specified in [RFC3961], but do
	do not use the simplified profile.		not use the simplified profile.
	The new encryption types use AES in CBC mode, but do not use		The new encryption types use AES in CBC mode with ciphertext stealing
	ciphertext stealing as in [RFC3962]. Instead, the messages are		similar to [RFC3962] but with several variations.
	padded to a multiple of the AES block size as described in Section
	6.3 of [RFC5652].
	The new types use the PBKDF2 algorithm for key generation from		The new types use the PBKDF2 algorithm for key generation from
	strings, with a modification to the use in [RFC3962] that the hash		strings, with a modification to the use in [RFC3962] that the hash
	algorithm in the pseudorandom function used by PBKDF2 will be SHA-256		algorithm in the pseudorandom function used by PBKDF2 will be SHA-256
	instead of SHA-1.		instead of SHA-1.
	The new types use key derivation to produce keys for encryption,		The new types use key derivation to produce keys for encryption,
	integrity protection, and checksum operations as in [RFC3962].		integrity protection, and checksum operations as in [RFC3962].
	However, a key derivation function from [SP800-108] which uses the		However, a key derivation function from [SP800-108] which uses the
	SHA-256 or SHA-384 hash algorithm is used in place of the DK key		SHA-256 or SHA-384 hash algorithm is used in place of the DK key
	derivation function used in [RFC3961].		derivation function used in [RFC3961].
	The new types use the HMAC algorithm with a hash from the SHA-2		The new types use the HMAC algorithm with a hash from the SHA-2
	family for integrity protection and checksum operations.		family for integrity protection and checksum operations.
	2. Conventions used in this Document		2. Conventions used in this Document
	The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",		The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
	"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this		"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
	document are to be interpreted as described in RFC 2119 [RFC2119].		document are to be interpreted as described in RFC 2119 [RFC2119].
	3. Protocol Key Representation		3. 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).
	4. Key Generation from Pass Phrases		4. Key Generation from Pass Phrases
	skipping to change at page 4, line 14 ¶		skipping to change at page 4, line 13 ¶
	information such as the principal's realm and name components.		information such as the principal's realm and name components.
	* The final key derivation step uses the algorithm KDF-HMAC-SHA2		* The final key derivation step uses the algorithm KDF-HMAC-SHA2
	defined below in Section 5 instead of the DK function.		defined below in Section 5 instead of the DK function.
	* If no string-to-key parameters are specified, the default number		* If no string-to-key parameters are specified, the default number
	of iterations is raised to 32,768.		of iterations is raised to 32,768.
	To ensure that different long-term keys are used with different		To ensure that different long-term keys are used with different
	enctypes, we prepend the enctype name to the salt string, separated		enctypes, we prepend the enctype name to the salt string, separated
	by a null byte. The enctype name is "aes128-cbc-hmac-sha256-128" or		by a null byte. The enctype name is "aes128-cts-hmac-sha256-128" or
	"aes256-cbc-hmac-sha384-192" (without the quotes). The user's long-		"aes256-cts-hmac-sha384-192" (without the quotes). The user's long-
	term key is derived as follows		term key is derived as follows
	saltp = enctype-name | 0x00 | salt		saltp = enctype-name | 0x00 | salt
	tkey = random2key(PBKDF2(passphrase, saltp,		tkey = random-to-key(PBKDF2(passphrase, saltp,
	iter_count, keylength))		iter_count, keylength))
	key = KDF-HMAC-SHA2(tkey, "kerberos") where "kerberos" is the		key = KDF-HMAC-SHA2(tkey, "kerberos") where "kerberos" is the
	byte string {0x6b 0x65 0x72 0x62 0x65 0x72 0x6f 0x73}.		byte string {0x6b 0x65 0x72 0x62 0x65 0x72 0x6f 0x73}.
	where the pseudorandom function used by PBKDF2 is the SHA-256 HMAC of		where the pseudorandom function used by PBKDF2 is the SHA-256 HMAC of
	the passphrase and salt, the value for keylength is the AES key		the passphrase and salt, the value for keylength is the AES key
	length, and the algorithm KDF-HMAC-SHA2 is defined in Section 5.		length, and the algorithm KDF-HMAC-SHA2 is defined in Section 5.
	5. Key Derivation Function		5. 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. The counter i is expressed		which uses the HMAC algorithm as the PRF. The counter i is expressed
	as four octets in big-endian order. The length of the output key in		as four octets in big-endian order. The length of the output key in
	bits (denoted as k) is also represented as four octets in big-endian		bits (denoted as k) is also represented as four octets in big-endian
	order. The "Label" input to the KDF is the usage constant supplied		order. The "Label" input to the KDF is the usage constant supplied
	to the key derivation function, and the "Context" input is null.		to the key derivation function, and the "Context" input is null.
	When the encryption type is aes128-cbc-hmac-sha256-128:		When the encryption type is aes128-cts-hmac-sha256-128:
	n = 1		n = 1
	K1 = HMAC-SHA-256(key, 00 00 00 01 | constant | 0x00 | 00 00 00 80)		K1 = HMAC-SHA-256(key, 00 00 00 01 | constant | 0x00 | 00 00 00 80)
	DR(key, constant) = First 128 bits of K1		DR(key, constant) = First 128 bits of K1
	KDF-HMAC-SHA2(key, constant) = random-to-key(DR(key, constant))		KDF-HMAC-SHA2(key, constant) = random-to-key(DR(key, constant))
	When the encryption type is aes256-cbc-hmac-sha384-192:		When the encryption type is aes256-cts-hmac-sha384-192:
	n = 1		n = 1
	K1 = HMAC-SHA-384(key, 00 00 00 01 | constant | 0x00 | 00 00 01 00)		K1 = HMAC-SHA-384(key, 00 00 00 01 | constant | 0x00 | 00 00 01 00)
	DR(key, constant) = First 256 bits of K1		DR(key, constant) = First 256 bits of K1
	KDF-HMAC-SHA2(key, constant) = random-to-key(DR(key, constant))		KDF-HMAC-SHA2(key, constant) = random-to-key(DR(key, constant))
	6. Kerberos Algorithm Protocol Parameters		6. Kerberos Algorithm Protocol Parameters
	The following parameters apply to the encryption types aes128-cbc-		The following parameters apply to the encryption types aes128-cts-
	hmac-sha256-128 and aes256-cbc-hmac-sha384-192.		hmac-sha256-128 and aes256-cts-hmac-sha384-192.
	The key-derivation function described in the previous section is used		The key-derivation function described in the previous section is used
	to produce the three intermediate keys. CBC mode [SP800-38A]		to produce the three intermediate keys. Typically, CBC mode [SP800-
	requires the input be padded to a multiple of the encryption		38A] requires the input be padded to a multiple of the encryption
	algorithm block size, which is 128 bits for AES. The input will be		algorithm block size, which is 128 bits for AES. However, to avoid
	padded as described in Section 6.3 of [RFC5652] in which the value of		ciphertext expansion, we use the CBC-CS3 variant to CBC mode defined
	each added octet equals the number of octets that are added.		in [SP800-38A+].
	Each encryption will use a freshly generated 16-octet initialization		Each encryption will use a freshly generated 16-octet nonce generated
	vector generated at random by the message originator.		at random by the message originator. The initialization vector (IV)
			used by AES is obtained by xoring the random nonce with the
			cipherstate.
	The ciphertext is the concatenation of the initialization vector, the		The ciphertext is the concatenation of the random nonce, the output
	output of AES in CBC mode, and the HMAC of the plaintext and padding		of AES in CBC-CS3 mode, and the HMAC of the initialization vector
	using either SHA-256 or SHA-384. The output of SHA-256 is truncated		concatenated with the AES output. The HMAC is computed using either
	to 128 bits and the output of SHA-384 is truncated to 192 bits.		SHA-256 or SHA-384. The output of SHA-256 is truncated to 128 bits
	Sample test vectors are given in Appendix A.		and the output of SHA-384 is truncated to 192 bits. Sample test
			vectors are given in Appendix A.
	Decryption is performed by removing the HMAC, decrypting the		Decryption is performed by removing the HMAC, verifying the HMAC
	remainder, verifying the HMAC, and verifying and removing the		against the remainder, and then decrypting the remainder if the HMAC
	padding.		is correct.
	The encryption and checksum mechanisms below use the following		The encryption and checksum mechanisms below use the following
	notation from [RFC3961].		notation from [RFC3961].
	HMAC output size, h		HMAC output size, h
	message block size, m		message block size, m
	encryption/decryption functions, E and D		encryption/decryption functions, E and D
	cipher block size, c		cipher block size, c
	Encryption Mechanism for AES-CBC-HMAC-SHA2		Encryption Mechanism for AES-CBC-HMAC-SHA2
	skipping to change at page 5, line 50 ¶		skipping to change at page 6, line 4 ¶
	protocol key format 128- or 256-bit string		protocol key format 128- or 256-bit string
	specific key structure Three protocol-format keys: { Kc, Ke, Ki }.		specific key structure Three protocol-format keys: { Kc, Ke, Ki }.
	required checksum As defined below.		required checksum As defined below.
	mechanism		mechanism
	key-generation seed key size (128 or 256 bits)		key-generation seed key size (128 or 256 bits)
	length		length
			cipher state Random nonce of length c (128 bits)
	cipher state Initial vector of length c (128 bits)
	initial cipher state All bits zero		initial cipher state All bits zero
	encryption function N = random nonce of length c (128 bits)		encryption function N = random nonce of length c (128 bits)
			IV = N + cipherState (+ denotes XOR)
	pad = Shortest string of non-zero length to		C = E(Ke, plaintext, IV)
	bring plaintext to a length that is a		using CBC-CS3-Encrypt defined
	multiple of m. The value of each added		in [SP800-38A+]
	octet equals the number of octets that		H = HMAC(Ki, N | C)
	are added.
	N1 = N + cipherState (+ denotes XOR)
	C = E(Ke, plaintext | pad, N1)
	H = HMAC(Ki, N | plaintext | pad)
	ciphertext = N | C | H[1..h]		ciphertext = N | C | H[1..h]
	cipherState = N		cipherState = N
	decryption function (N,C,H) = ciphertext		decryption function (N, C, H) = ciphertext
	(P, pad) = D(Ke, C, N + cipherState)		if (H != HMAC(Ki, N | C)[1..h])
	if (H != HMAC(Ki, N | P | pad)[1..h]		stop, report error
	or pad is bad)		IV = N + cipherState (+ denotes XOR)
	report error		P = D(Ke, C, IV)
			using CBC-CS3-Decrypt defined
			in [SP800-38A+]
	cipherState = N		cipherState = N
	pseudo-random function Kp = KDF-HMAC-SHA2(protocol-key, "prf")		pseudo-random function Kp = KDF-HMAC-SHA2(protocol-key, "prf")
	PRF = HMAC(Kp, octet-string)		PRF = HMAC(Kp, octet-string)
	key generation functions:		key generation functions:
	string-to-key function tkey = random2key(PBKDF2(passphrase, saltp,		string-to-key function tkey = random-to-key(PBKDF2(passphrase, saltp,
	iter_count,		iter_count,
	keylength))		keylength))
	base-key = KDF-HMAC-SHA2(tkey, "kerberos")		base-key = KDF-HMAC-SHA2(tkey, "kerberos")
	where the pseudorandom function used by PBKDF2		where the pseudorandom function used by PBKDF2
	is the SHA-256 HMAC of the passphrase and salt		is the SHA-256 HMAC of the passphrase and salt
	default string-to-key 00 00 80 00		default string-to-key 00 00 80 00
	parameters		parameters
	random-to-key function identity function		random-to-key function identity function
	key-derivation function KDF-HMAC-SHA2 as defined in Section 5. The		key-derivation function KDF-HMAC-SHA2 as defined in Section 5. The
	key usage number is expressed as four octets		key usage number is expressed as four octets
	in big-endian order.		in big-endian order.
	Kc = KDF-HMAC-SHA2(base-key, usage | 0x99);		Kc = KDF-HMAC-SHA2(base-key, usage | 0x99)
	Ke = KDF-HMAC-SHA2(base-key, usage | 0xAA);		Ke = KDF-HMAC-SHA2(base-key, usage | 0xAA)
	Ki = KDF-HMAC-SHA2(base-key, usage | 0x55);		Ki = KDF-HMAC-SHA2(base-key, usage | 0x55);
	Checksum Mechanism for AES-CBC-HMAC-SHA2		Checksum Mechanism for AES-CTS-HMAC-SHA2
	------------------------------------------------------------------------		------------------------------------------------------------------------
	associated cryptosystem AES-128-CBC or AES-256-CBC as appropriate		associated cryptosystem AES-128-CBC or AES-256-CBC as appropriate
	get_mic HMAC(Kc, message)[1..h]		get_mic HMAC(Kc, message)[1..h]
	verify_mic get_mic and compare		verify_mic get_mic and compare
	Using this profile with each key size gives us two each of encryption		Using this profile with each key size gives us two each of encryption
	and checksum algorithm definitions.		and checksum algorithm definitions.
	+--------------------------------------------------------------------+		+--------------------------------------------------------------------+
	| encryption types |		| encryption types |
	+--------------------------------------------------------------------+		+--------------------------------------------------------------------+
	| type name etype value key size |		| type name etype value key size |
	+--------------------------------------------------------------------+		+--------------------------------------------------------------------+
	| aes128-cbc-hmac-sha256-128 TBD1 128 |		| aes128-cts-hmac-sha256-128 TBD1 128 |
	| aes256-cbc-hmac-sha384-192 TBD2 256 |		| aes256-cts-hmac-sha384-192 TBD2 256 |
	+--------------------------------------------------------------------+		+--------------------------------------------------------------------+
	+--------------------------------------------------------------------+		+--------------------------------------------------------------------+
	| checksum types |		| checksum types |
	+--------------------------------------------------------------------+		+--------------------------------------------------------------------+
	| type name sumtype value length |		| type name sumtype value length |
	+--------------------------------------------------------------------+		+--------------------------------------------------------------------+
	| hmac-sha256-128-aes128 TBD3 128 |		| hmac-sha256-128-aes128 TBD3 128 |
	| hmac-sha384-192-aes256 TBD4 192 |		| hmac-sha384-192-aes256 TBD4 192 |
	+--------------------------------------------------------------------+		+--------------------------------------------------------------------+
	These checksum types will be used with the corresponding encryption		These checksum types will be used with the corresponding encryption
	types defined above.		types defined above.
	7. IANA Considerations		7. IANA Considerations
	IANA is requested to assign:		IANA is requested to assign:
	1. Encryption type numbers for aes128-cbc-hmac-sha256-128 and		1. Encryption type numbers for aes128-cts-hmac-sha256-128 and
	aes256-cbc-hmac-sha384-192 in the Kerberos Encryption Type		aes256-cts-hmac-sha384-192 in the Kerberos Encryption Type
	Numbers registry.		Numbers registry.
	Etype encryption type Reference		Etype encryption type Reference
	----- --------------- ---------		----- --------------- ---------
	TBD1 aes128-cbc-hmac-sha256-128 [I.D.burgin-kerberos-aes-		TBD1 aes128-cts-hmac-sha256-128 [I.D.burgin-kerberos-aes-
	cbc-hmac-sha2]		cbc-hmac-sha2]
	TBD2 aes256-cbc-hmac-sha384-192 [I.D.burgin-kerberos-aes-		TBD2 aes256-cts-hmac-sha384-192 [I.D.burgin-kerberos-aes-
	cbc-hmac-sha2]		cbc-hmac-sha2]
	2. Checksum type numbers for hmac-sha256-128-aes128 and hmac-sha384-		2. Checksum type numbers for hmac-sha256-128-aes128 and hmac-sha384-
	192-aes256 in the Kerberos Checksum Type Numbers registry.		192-aes256 in the Kerberos Checksum Type Numbers registry.
	Sumtype Checksum type Size Reference		Sumtype Checksum type Size Reference
	------- ------------- ---- ---------		------- ------------- ---- ---------
	TBD3 hmac-sha256-128-aes128 16 [I.D.burgin-kerberos-		TBD3 hmac-sha256-128-aes128 16 [I.D.burgin-kerberos-
	aes-cbc-hmac-sha2]		aes-cbc-hmac-sha2]
	TBD4 hmac-sha384-192-aes256 24 [I.D.burgin-kerberos-		TBD4 hmac-sha384-192-aes256 24 [I.D.burgin-kerberos-
	aes-cbc-hmac-sha2]		aes-cbc-hmac-sha2]
	8. Security Considerations		8. Security Considerations
	Padding oracle attacks were introduced by Vaudenay in [POA]. The
	attack relies on an oracle that decrypts messages that were encrypted
	using CBC mode with PKCS#5 padding and returns an answer to the
	sender about whether the padding is correct. This information allows
	an attacker to recover the plaintext from an encrypted message
	through repeated inquiries to the oracle even though the encryption
	key is never learned by the attacker. The attack can be mitigated by
	returning a single error type when decryption fails and not
	distinguishing between failed MAC check and failed padding check.
	This specification requires implementations to generate random		This specification requires implementations to generate random
	values. The use of inadequate pseudo-random number generators		values. The use of inadequate pseudo-random number generators
	(PRNGs) can result in little or no security. The generation of		(PRNGs) can result in little or no security. The generation of
	quality random numbers is difficult. NIST Special Publication 800-90		quality random numbers is difficult. NIST Special Publication 800-90
	[SP800-90] and [RFC4086] offer random number generation guidance.		[SP800-90] and [RFC4086] offer random number generation guidance.
	This document specifies a mechanism for generating keys from pass		This document specifies a mechanism for generating keys from pass
	phrases or passwords. The salt and iteration count resist brute		phrases or passwords. The salt and iteration count resist brute
	force and dictionary attacks, however, it is still important to		force and dictionary attacks, however, it is still important to
	choose or generate strong passphrases.		choose or generate strong passphrases.
	9 References		9. References
	9.1 Normative References		9.1. Normative References
			[SP800-38A+] National Institute of Standards and Technology,
			"Recommendation for Block Cipher Modes of Operation:
			Three Variants of Ciphertext Stealing for CBC Mode",
			Addendum to NIST Special Publication 800-38A, October
			2010.
	[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.
	[RFC3961] Raeburn, K., "Encryption and Checksum Specifications for		[RFC3961] Raeburn, K., "Encryption and Checksum Specifications for
	Kerberos 5", RFC 3961, February 2005.		Kerberos 5", RFC 3961, February 2005.
	[RFC3962] Raeburn, K., "Advanced Encryption Standard (AES)		[RFC3962] Raeburn, K., "Advanced Encryption Standard (AES)
	Encryption for Kerberos 5", RFC 3962, February 2005.		Encryption for Kerberos 5", RFC 3962, February 2005.
	[RFC4086] Eastlake 3rd, D., Schiller, J., and S. Crocker,		[RFC4086] Eastlake 3rd, D., Schiller, J., and S. Crocker,
	"Randomness Requirements for Security", BCP 106,		"Randomness Requirements for Security", BCP 106,
	RFC 4086, June 2005.		RFC 4086, June 2005.
	[RFC5652] Housley, R., "Cryptographic Message Syntax (CMS)", STD
	70, RFC 5652, September 2009.
	[FIPS197] National Institute of Standards and Technology,		[FIPS197] National Institute of Standards and Technology,
	"Advanced Encryption Standard (AES)", FIPS PUB 197,		"Advanced Encryption Standard (AES)", FIPS PUB 197,
	November 2001.		November 2001.
	9.2 Informative References		9.2. Informative References
	[SP800-38A] National Institute of Standards and Technology,		[SP800-38A] National Institute of Standards and Technology,
	"Recommendation for Block Cipher Modes of Operation -		"Recommendation for Block Cipher Modes of Operation -
	Methods and Techniques", NIST Special Publication 800-		Methods and Techniques", NIST Special Publication 800-
	38A, February 2001.		38A, February 2001.
	[SP800-90] National Institute of Standards and Technology,		[SP800-90] National Institute of Standards and Technology,
	Recommendation for Random Number Generation Using		Recommendation for Random Number Generation Using
	Deterministic Random Bit Generators (Revised), NIST		Deterministic Random Bit Generators (Revised), NIST
	Special Publication 800-90, March 2007.		Special Publication 800-90, March 2007.
	skipping to change at page 9, line 34 ¶		skipping to change at page 9, line 27 ¶
	[SP800-108] National Institute of Standards and Technology,		[SP800-108] National Institute of Standards and Technology,
	"Recommendation for Key Derivation Using Pseudorandom		"Recommendation for Key Derivation Using Pseudorandom
	Functions", NIST Special Publication 800-108, October		Functions", NIST Special Publication 800-108, October
	2009.		2009.
	[SP800-132] National Institute of Standards and Technology,		[SP800-132] National Institute of Standards and Technology,
	"Recommendation for Password-Based Key Derivation, Part		"Recommendation for Password-Based Key Derivation, Part
	1: Storage Applications", NIST Special Publication 800-		1: Storage Applications", NIST Special Publication 800-
	132, June 2010.		132, June 2010.
	[POA] Vaudenay, Serge, "Security Flaws Induced by CBC Padding
	Applications to SSL, IPSEC, WTLS...", EUROCRYPT 2002.
	Appendix A. AES-CBC Test Vectors		Appendix A. AES-CBC Test Vectors
	TBD		TBD
	Authors' Addresses		Authors' Addresses
	Kelley W. Burgin		Kelley W. Burgin
	National Security Agency		National Security Agency
	EMail: kwburgi@tycho.ncsc.mil		EMail: kwburgi@tycho.ncsc.mil
End of changes. 38 change blocks.
	89 lines changed or deleted		77 lines changed or added
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