Network Working Group A. Davletshina, Ed. Internet-Draft A. Urivskiy Intended status: Informational A. Rybkin Expires: 18 December 2022 L. Tychina I. Parshin InfoTeCS 16 June 2022 IPlir network layer security protocol draft-iplir-protocol-01 Abstract This document specifies the IPlir network layer security protocol. It describes how to provide a set of security services for traffic over public and corporate networks using the TCP/IP stack. 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 https://datatracker.ietf.org/drafts/current/. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress." This Internet-Draft will expire on 18 December 2022. Copyright Notice Copyright (c) 2022 IETF Trust and the persons identified as the document authors. All rights reserved. This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (https://trustee.ietf.org/ license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Revised BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Revised BSD License. Davletshina, et al. Expires 18 December 2022 [Page 1] Internet-Draft Abbreviated Title June 2022 Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3 1.1. Scope . . . . . . . . . . . . . . . . . . . . . . . . . . 3 1.2. Audience . . . . . . . . . . . . . . . . . . . . . . . . 4 2. Conventions Used in This Document . . . . . . . . . . . . . . 4 3. Definitions and Notations . . . . . . . . . . . . . . . . . . 4 3.1. Definitions . . . . . . . . . . . . . . . . . . . . . . . 4 3.2. Notations . . . . . . . . . . . . . . . . . . . . . . . . 6 4. System overview . . . . . . . . . . . . . . . . . . . . . . . 12 4.1. IPlir packet contents . . . . . . . . . . . . . . . . . . 12 4.2. IPlir message content . . . . . . . . . . . . . . . . . . 12 4.3. Tuples (type, length, value) . . . . . . . . . . . . . . 15 4.3.1. Pair of IPv4 addresses . . . . . . . . . . . . . . . 15 4.3.2. Pair of IPv6 addresses . . . . . . . . . . . . . . . 16 4.4. IPlir packet structure and IPlir header location . . . . 17 4.4.1. Transport mode . . . . . . . . . . . . . . . . . . . 18 4.4.2. Light tunnel . . . . . . . . . . . . . . . . . . . . 19 4.4.3. Tunnel mode . . . . . . . . . . . . . . . . . . . . . 20 5. Security Considerations . . . . . . . . . . . . . . . . . . . 21 5.1. Encryption and MAC . . . . . . . . . . . . . . . . . . . 21 5.2. Cryptographic keys . . . . . . . . . . . . . . . . . . . 22 5.3. Cryptographic suites . . . . . . . . . . . . . . . . . . 23 5.3.1. MAGMA-MGM cryptographic suite: CS = 1 . . . . . . . . 25 5.3.1.1. Exchange keys . . . . . . . . . . . . . . . . . . 25 5.3.1.2. Requirements for initializing values . . . . . . 25 5.3.1.3. Key derivation algorithms . . . . . . . . . . . . 26 5.3.1.4. Encryption and MAC algorithms . . . . . . . . . . 27 5.3.2. KUZN-CTR-CMAC cryptographic suite: CS=2 . . . . . . . 31 5.3.2.1. Exchange keys . . . . . . . . . . . . . . . . . . 32 5.3.2.2. Requirements for initializing values . . . . . . 32 5.3.2.3. Key derivation algorithms . . . . . . . . . . . . 33 5.3.2.4. Encryption and MAC algorithms . . . . . . . . . . 34 5.3.3. AES-128-GCM cryptographic suite: CS = 129 . . . . . . 38 5.3.3.1. Exchange keys . . . . . . . . . . . . . . . . . . 39 5.3.3.2. Requirements for initializing values . . . . . . 39 5.3.3.3. Key derivation algorithms . . . . . . . . . . . . 40 5.3.3.4. Encryption and MAC algorithms . . . . . . . . . . 41 5.3.4. AES-256-CTR-CMAC cryptographic suite: CS = 132 . . . 45 5.3.4.1. Exchange keys . . . . . . . . . . . . . . . . . . 46 5.3.4.2. Requirements for initializing values . . . . . . 46 5.3.4.3. Key derivation algorithms . . . . . . . . . . . . 47 5.3.4.4. Encryption and MAC algorithms . . . . . . . . . . 48 5.3.5. AES-256-CFB-CMAC cryptographic suite: CS = 134 . . . 52 5.3.5.1. Exchange keys . . . . . . . . . . . . . . . . . . 53 5.3.5.2. Requirements for initializing values . . . . . . 53 5.3.5.3. Key derivation algorithms . . . . . . . . . . . . 53 5.3.5.4. Encryption and MAC algorithms . . . . . . . . . . 55 Davletshina, et al. Expires 18 December 2022 [Page 2] Internet-Draft Abbreviated Title June 2022 6. IPlir packet processing . . . . . . . . . . . . . . . . . . . 58 6.1. IP and IPlir packet fragmentation . . . . . . . . . . . . 59 6.2. Source IP packet protection by the sender host . . . . . 59 6.3. IPlir packet processing on the forward host . . . . . . . 60 6.4. Source IP packet recovery by the recipient host . . . . . 61 7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 62 8. References . . . . . . . . . . . . . . . . . . . . . . . . . 62 8.1. Normative References . . . . . . . . . . . . . . . . . . 62 8.2. Informative References . . . . . . . . . . . . . . . . . 64 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 64 1. Introduction 1.1. Scope The IPlir protocol may be used to protect IP packets during their transmission via communication channels. IP packet protection means ensuring integrity and authenticity of the data source of the packets with an option of also ensuring their confidentiality. For this purpose, when IPlir is applied, encapsulation of source IP packets, calculation of message authentication codes for the encapsulated packets and service information along with optional packet encryption are used. In addition, the IPlir protocol allows for protection against replay attacks based on the use of counter values and/or timestamps. The IPlir protocol can be used to create Virtual Private Networks at the 3rd (network) layer of the basic ISO OSI reference model. Data is protected during transfer of IP packets between any two hosts supporting the IPlir protocol, including options of data exchange between two end hosts, an end host and a security gateway, and two security gateways. All protection mechanisms are implemented without establishing a connection (in terms of network) between the two interacting hosts. This document is not a Security Architecture for the Internet; it addresses security only at the network layer, provided through the use of a combination of cryptographic and protocol security mechanisms. This document does not have IETF consensus and does not imply IETF support for IPlir. Davletshina, et al. Expires 18 December 2022 [Page 3] Internet-Draft Abbreviated Title June 2022 1.2. Audience The target audience for this document is primarily individuals who implement this network layer security technology or who architect systems that will use this technology. Technically adept users of this technology (end users or system administrators) also are part of the target audience. This document assumes that the reader is familiar with the Internet Protocol (IP), related networking technology, and general information system security terms and concepts. 2. Conventions Used in This Document The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all capitals, as shown here. 3. Definitions and Notations 3.1. Definitions This document uses the following terms and definitions: AEAD: Authenticated Encryption with Associated Data, cryptographic suite: a set of cryptographic algorithms and parameters used in the IPlir, CTR mode: a block cipher mode of operation when a cipher key stream is applied to plaintext data under a specific law, derived key: a key derived from the shared secret (original key) and random and/or fixed mutually known data, end-to-end MAC: MAC implemented between the source and destination hosts, exchange key: a key known only to the specified pair of hosts used to derive keys, host (network host): a network device with a unique ID and IPlir support, Davletshina, et al. Expires 18 December 2022 [Page 4] Internet-Draft Abbreviated Title June 2022 initializing value: a value transmitted over the communication channel and used in defining the starting point of a symmetric cryptographic technique, IP packet (network packet): a logically indivisible data block at the network layer of the basic ISO OSI reference model relating to the IP, IPlir message: the data contained in the IPlir packet body, IPlir operation mode: one of the three IPlir operating modes: transport, light tunnel, and tunnel, IPlir packet: an IP packet protected by IPlir, IPlir packets reception policy: a set of rules for processing incoming IPlir packets, key: a sequence of symbols that controls the operation of a cryptographic transformation, key system: a set of keys, their deployment and management subsystems, MAC (message authentication code): a fixed-length string of bits (tag) computed by applying a symmetric cryptographic technique to the message and appended to that message in order to provide its integrity and authenticity of the data source, network host context: the information necessary to process/create IPlir packets from/to the network host logically related to the given one, security policy: a set of rules for IP traffic processing by the network host, sender host: the host creating an IPlir packet from a source IP packet, source IP packet: an IP packet before it was protected by the IPlir, symmetric cryptographic technique: a cryptographic technique that uses the same key for both the originator's and recipient's transformation, recipient host: the host recovering the source IP packet from an IPlir packet, Davletshina, et al. Expires 18 December 2022 [Page 5] Internet-Draft Abbreviated Title June 2022 routing of IPlir packets: a function of forwarding IPlir packets by a network host during reception of IPlir packets addressed to this network host from the IP perspective, but for which it is not the recipient host, transit MAC: MAC implemented between two neighbor hosts in a packet transfer chain, transit host: the host implementing the function of routing IPlir packets. 3.2. Notations The following notations are used in this document: +============================+====================================+ +============================+====================================+ | V^{*} | a set of all finite length binary | | | strings, including an empty string | +----------------------------+------------------------------------+ | |x| | the length (number of components) | | | of the string x \in V^{*} | +----------------------------+------------------------------------+ | V_s | a set of all binary strings with a | | | length of s, where s is a non- | | | negative integer; numbering of | | | substrings and components is | | | right-to-left, starting with zero | +----------------------------+------------------------------------+ | x||y | concatenation of binary strings x | | | and y from V^{*}, i.e., a string | | | from V_{|x|+|y|}, wherein the left | | | substring from V_{|x|} is the same | | | as string x, and the right | | | substring from V_{|y|} is the same | | | as string y | +----------------------------+------------------------------------+ | 0^r | a binary string consisting of r | | | zeros | +----------------------------+------------------------------------+ | LSB_s(x) | truncation of binary string x with | | | a length of m, m >= s, to a binary | | | string with a length of s | | | according to the following rule: | | | LSB_s(x_{m-1} || ... || x_1 || | | | x_0) = x_{s-1} || ... || x_1 || | | | x_0, xi \in V_1, i = 0,1,...,m-1 | +----------------------------+------------------------------------+ Davletshina, et al. Expires 18 December 2022 [Page 6] Internet-Draft Abbreviated Title June 2022 | IntToVec_s(x) | representation of the ring element | | | x \in Z_{2^s} as a binary string | | | with a length of s: for x = x_0 + | | | 2 * x_1 + ... + 2^{s-1} * x_{s-1}, | | | where x_i \in V_1, i = | | | 0,1,...,s-1, the following | | | equation is true IntToVec_s(x) = | | | x_{s-1} || ... || x_1 || x_0 | +----------------------------+------------------------------------+ | CharToByte(c) | representation of the c symbol as | | | a binary string of length 8 | | | calculated according to the | | | following rule: CharToByte(c) = | | | 0 || IntToVec_7(ASCII(c)), where | | | ASCII(c) \in Z_{2^7} is the ASCII | | | representation of the c symbol | +----------------------------+------------------------------------+ | StrToVec_s(string) | representation of the string of | | | symbols string = | | | 'c_{m-1}c_{m-2}...c_0' consisting | | | of m symbols as a binary string | | | with a length of s, s >= 8*m | | | according to the following rule: | | | StrToVec_s('c_{m-1}c_{m-2}...c_0') | | | = 0^{s-8*m} || | | | CharToByte(c_{m-1}) || | | | CharToByte(c_{m-2}) || ... || | | | CharToByte(c_0) | +----------------------------+------------------------------------+ | K_ENC | packet encryption key. The length | | | of the value is determined by the | | | used cryptographic suite | +----------------------------+------------------------------------+ | K_MAC | packet end-to-end MAC key. The | | | length of the value is determined | | | by the used cryptographic suite | +----------------------------+------------------------------------+ | K_AEAD | packet encryption and end-to-end | | | MAC key. The length of the value | | | is determined by the used | | | cryptographic suite | +----------------------------+------------------------------------+ | K_TMAC | packet transit MAC key. The | | | length of the value is determined | | | by the used cryptographic suite | +----------------------------+------------------------------------+ | Version | IPlir header version. This | | | document describes the IPlir | Davletshina, et al. Expires 18 December 2022 [Page 7] Internet-Draft Abbreviated Title June 2022 | | header of Version = 1. The field | | | length is 8 bit | +----------------------------+------------------------------------+ | CS | cryptographic suite identifier | | | determining the contents of | | | cryptographic mechanisms and their | | | parameters used to create the | | | IPlir packet. The field length is | | | 8 bit | +----------------------------+------------------------------------+ | T | the transit MAC field flag. If T | | | = 1, the IPlir trailer contains | | | fields TransitIdentifier, | | | TransitIntegrityCheckValue and | | | TransitInitValue, otherwise the | | | fields are absent. When | | | calculating and checking the end- | | | to-end MAC (ICV) insert the T | | | field has to be set to 0. The | | | field length is 1 bit | +----------------------------+------------------------------------+ | D | the DestinationIdentifier field | | | flag. If D = 1, the header | | | contains the DestinationIdentifier | | | field, otherwise the field is | | | absent. The destination host | | | identifier is required for routing | | | of IPlir packets. The field | | | length is 1 bit | +----------------------------+------------------------------------+ | ExtID | the flag of extended network host | | | identifiers. If ExtID = 0, all | | | the network host identifiers (the | | | SourceIdentifier field and, if | | | available, DestinationIdentifier | | | and TransitIdentifier fields) are | | | 32 bits long. If ExtID = 1, all | | | the network host identifiers are | | | 64 bits long. The field length is | | | 1 bit | +----------------------------+------------------------------------+ | ExtSN | the packet extended sequence | | | number flag. If ExtSN=0, the | | | packet SequenceNumber field is 32 | | | bits long. If ExtSN = 1, the | | | SequenceNumber field is 64 bits | | | long. The field length is 1 bit | +----------------------------+------------------------------------+ Davletshina, et al. Expires 18 December 2022 [Page 8] Internet-Draft Abbreviated Title June 2022 | DAR | the flag of disabling the anti- | | | replay mechanism. The use of the | | | flag is regulated by security | | | policies. The field length is 1 | | | bit | +----------------------------+------------------------------------+ | R1 | the field reserved for future use. | | | When IPlir header is generated, | | | the field must contain all zeros. | | | The receiving end must not analyze | | | the field content. The field | | | length is 3 bits | +----------------------------+------------------------------------+ | KN | the number of the exchange key | | | used to encrypt and calculate the | | | end-to-end MAC, but not the | | | transit MAC. The field length is | | | 4 bits | +----------------------------+------------------------------------+ | TKN | the number of the exchange key | | | used to calculate the transit MAC. | | | If the transit MAC is not used, | | | i.e., T = 0, the field value | | | should be 0. When calculating and | | | checking the end-to-end MAC (ICV), | | | the TKN field must be filled with | | | zeros. The field length is 4 bits | +----------------------------+------------------------------------+ | Timestamp | packet send time. The field | | | contains the send time value based | | | on the astronomical clock of the | | | sender host in the POSIX time | | | format less 0x40000000 seconds. | | | The estimated overflow time is the | | | year 2140. The field length is 32 | | | bits | +----------------------------+------------------------------------+ | SourceIdentifier | the source host identifier used by | | | the destination host to identify | | | the IPlir packet sender and the | | | related context of the sender host | | | for packet processing. The field | | | length is 32 bits with ExtID = 0, | | | or 64 bits with ExtID = 1 | +----------------------------+------------------------------------+ | DestinationIdentifier | the destination host identifier | | | required for routing of IPlir | | | packets. The field is available, | Davletshina, et al. Expires 18 December 2022 [Page 9] Internet-Draft Abbreviated Title June 2022 | | if D = 0. The field length is 32 | | | bits with ExtID = 0, or 64 bits | | | with ExtID = 1 | +----------------------------+------------------------------------+ | SequenceNumber | the packet sequence number; an | | | unsigned integer. The field | | | length is 32 bits with ExtSN = 0, | | | or 64 bits with ExtSN = 1 | +----------------------------+------------------------------------+ | InitValue (IV) | an end-to-end initializing value | | | that can be used to execute | | | encryption operations and | | | calculate an end-to-end MAC, as | | | well as to derive keys for these | | | operations. The field length is | | | determined by the used | | | cryptographic suite | +----------------------------+------------------------------------+ | Type, Length, Value | (type, length, value) tuples | | | enabling transmission of | | | additional information within the | | | IPlir packet. Type is the type of | | | the value in the Value field. The | | | field length is 8 bit. Length is | | | the byte length of the Value | | | field. The field length is 8 bit. | | | Value is random data of the Type | | | type | +----------------------------+------------------------------------+ | PayloadData | a variable-length field containing | | | the source IP packet or its part, | | | depending on the IPlir operation | | | mode | +----------------------------+------------------------------------+ | Staffing | a (network) filler to make the | | | length of the IPlir suitable for | | | more efficient providing of the | | | IPlir message processing. The | | | Staffing field contains a sequence | | | of integers in a binary form: the | | | first byte contains digit 1, the | | | second one contains 2, etc. The | | | value length is determined by the | | | SL field value, if SL is absent (S | | | = 0) or has the value 0, there is | | | no Staffing field | +----------------------------+------------------------------------+ | SL | the number of bytes in the | Davletshina, et al. Expires 18 December 2022 [Page 10] Internet-Draft Abbreviated Title June 2022 | | Staffing field. The field is | | | available, if S = 1. The field | | | length is 8 bit | +----------------------------+------------------------------------+ | Mode | the mode in which the IPlir packet | | | was generated in. The field | | | length is 2 bits | +----------------------------+------------------------------------+ | TLV | Type, Length and Value field flag. | | | If TLV = 1, the IPlir body begins | | | with tuples (Type, Length, Value), | | | otherwise there are no tuples. | | | The field length is 1 bit | +----------------------------+------------------------------------+ | S | the SL field flag. If S = 1, the | | | IPlir body contains the SL field, | | | otherwise this field is absent. | | | The field length is 1 bit | +----------------------------+------------------------------------+ | R2 | the field reserved for future use. | | | When an IPlir message is | | | generated, the field must contain | | | all zeros. The receiving end must | | | not analyze the field content. | | | The field length is 4 bits | +----------------------------+------------------------------------+ | NextHeader | the source IP packet protocol | | | number. The field length is 8 bit | +----------------------------+------------------------------------+ | IntegrityCheckValue (ICV) | an end-to-end MAC calculated for | | | the data from the IPlir message | | | start and to the NextHeader field | | | inclusive. The field length is | | | determined by the used | | | cryptographic suite | +----------------------------+------------------------------------+ | TransitIdentifier | the identifier of the transit host | | | that routed the IPlir packet last. | | | Each transit host updates the | | | field value with its identifier. | | | The field is available, if T = 1. | | | The field length is 32 bits with | | | ExtID = 0, or 64 bits with ExtID = | | | 1 | +----------------------------+------------------------------------+ | TransitInitValue (TIV) | the transit initializing value | | | used to calculate a transit MAC | | | and derive keys for packet transit | Davletshina, et al. Expires 18 December 2022 [Page 11] Internet-Draft Abbreviated Title June 2022 | | MAC. The field is available, if T | | | = 1. The field length is | | | determined by the used | | | cryptographic suite | +----------------------------+------------------------------------+ | TransitIntegrityCheckValue | a transit MAC calculated for the | | (TICV) | data from the IPlir message start | | | and to the TransitInitValue field | | | inclusive. The field is | | | available, if T = 1. The field | | | length is determined by the used | | | cryptographic suite | +----------------------------+------------------------------------+ Table 1 4. System overview 4.1. IPlir packet contents The IPlir packet structure is shown in Figure 1. +------------+------------+--------------------+ | IP header | UDP header | IPlir message | +------------+------------+--------------------+ Figure 1: IPlir packet structure The IP header is the header of a standard IP packet. The UDP header is a standard UDP header only existing when additional encapsulation of the IPlir message in a UDP message is used. The IPlir protocol uses UDP destination port number 55777 as a default port. The IPlir message is the main part of the IPlir packet that includes protected data from the source IP packet and plaintext data required for IPlir packet processing. 4.2. IPlir message content The IPlir message contains: * IPlir header containing plaintext information related to encapsulation and protection of the source IP packet; * IPlir body containing information the encryption of which is optional; Davletshina, et al. Expires 18 December 2022 [Page 12] Internet-Draft Abbreviated Title June 2022 * IPlir trailer containing MACs, the transit host identifier, and the transit initializing value. The IPlir message structure is shown in Figure 2. Davletshina, et al. Expires 18 December 2022 [Page 13] Internet-Draft Abbreviated Title June 2022 +---+---------------+---------------+---------------+---------------+ | | 0 | 1 | 2 | 3 | +---+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |Bit|7|6|5|4|3|2|1|0|7|6|5|4|3|2|1|0|7|6|5|4|3|2|1|0|7|6|5|4|3|2|1|0| +---+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | | | | |E|E| | | | | | I | | | | |x|x|D| | | | | P | Version | CS |T|D|t|t|A| R1 | KN | TKN | | l | | | | |I|S|R| | | | | i | | | | |D|N| | | | | | r +---------------+---------------+-+-+-+-+-+-----+-------+-------+ | | Timestamp | | +---------------------------------------------------------------+ | h | SourceIdentifier | | e +---------------------------------------------------------------+ | a | DestinationIdentifier | | d +---------------------------------------------------------------+ | e | SequenceNumber | | r +---------------------------------------------------------------+ | | InitValue | +---+---------------+---------------+-------------------------------+ | | Type_1 | Length_1 | Value_1 (Length_1 byte) | | +---------------+---------------+-------------------------------+ | I | ... | | P +---------------+---------------+-------------------------------+ | l | Type_n | Length_n | Value_n (Length_n byte) | | i +---------------+---------------+-------------------------------+ | r | PayloadData | | +---------------------------------------------------------------+ | b | Staffing | | o | +---------------+---+-+-+-------+---------------+ | d | | | M |T| | | | | y | | SL | o |L|S| R2 | NextHeader | | | | | d |V| | | | | | | | e | | | | | +---+---------------+---------------+---+-+-+-------+---------------+ | t| IntegrityCheckValue (ICV) | |I r+---------------------------------------------------------------+ |P a| TransitIdentifier | |l i+---------------------------------------------------------------+ |i l| TransitInitValue | |r e+---------------------------------------------------------------+ | r| TransitIntegrityCheckValue (TICV) | +---+---------------------------------------------------------------+ Figure 2: IPlir message structure Davletshina, et al. Expires 18 December 2022 [Page 14] Internet-Draft Abbreviated Title June 2022 The IPlir message fields have a big-endian order of bytes. The numbering is left-to-right, the lead bytes have lower numbers. Numbering of bits inside bytes is right-to-left, the high bits have higher numbers. 4.3. Tuples (type, length, value) Tuples (Type, Length, Value) enable transmission of additional information within the IPlir message. The TLV field value indicates whether there are tuples. If its value is 1, there is one or more tuples in the beginning of the IPlir body. The Value field of any tuple should be divisible by 8 bits. The Length field indicates the Value field length in bytes. Permissible Type field values for the tuples are provided in Table 1. +============+==========================================+ | Type value | Description | +============+==========================================+ | 0 | the last tuple in the IPlir message; can | | | be used by the vendor for its own needs | +------------+------------------------------------------+ | 1 | a pair of IPv4 addresses | +------------+------------------------------------------+ | 2 | a pair of IPv6 addresses | +------------+------------------------------------------+ | 3-128 | not in use | +------------+------------------------------------------+ | 129-254 | can be used by the vendor for its own | | | needs | +------------+------------------------------------------+ | 255 | not in use | +------------+------------------------------------------+ Table 2: Type Field Values for Tuples The last tuple in the message is always type 0. The length of this tuple should be chosen so as to ensure effective IPlir message processing. 4.3.1. Pair of IPv4 addresses The Value field of the tuple of this type contains a pair of IPv4 addresses. The sender's address comes first, followed by the recipient's address. The addresses are transmitted in the network byte order. Davletshina, et al. Expires 18 December 2022 [Page 15] Internet-Draft Abbreviated Title June 2022 The main function of the tuple of this type is to preserve the IPv4 addresses from the source IP packet in the "Light tunnel" mode. The tuple structure is shown in Figure 3. +------+--------------+--------------+--------------+--------------+ |Bytes | 0 | 1 | 2 | 3 | +------+--------------+--------------+--------------+--------------+ | | | |Sender IPv4 | | | | Type = 1 | Length = 8 |address, byte | ... | | | | |No.1 (MSB) | | | +--------------+--------------+--------------+--------------+ | TLV | |Sender IPv4 |Recipient IPv4| | | | ... |address, byte |address, byte | ... | | area | |No.4 (LSB) |No.1 (MSB) | | | +--------------+--------------+--------------+--------------+ | | |Recipient IPv4| | | | | ... |address, byte | Not in use | Not in use | | | |No.4 (LSB) | | | +------+--------------+--------------+--------------+--------------+ Figure 3: Type = 1 Tuple Structure Note: Bytes labeled "not in use" contain information related to the following tuple. 4.3.2. Pair of IPv6 addresses The Value field of the tuple of this type contains a pair of IPv6 addresses. The sender's address comes first, followed by the recipient's address. The addresses are transmitted in the network byte order. The main function of the tuple of this type is to preserve the IPv6 addresses from the source IP packet in the "Light tunnel" mode. The tuple structure is shown in Figure 4. Davletshina, et al. Expires 18 December 2022 [Page 16] Internet-Draft Abbreviated Title June 2022 +------+--------------+--------------+--------------+--------------+ |Bytes | 0 | 1 | 2 | 3 | +------+--------------+--------------+--------------+--------------+ | | | |Sender IPv6 | | | | Type = 2 | Length = 32 |address, byte | ... | | | | |No.1 (MSB) | | | +--------------+--------------+--------------+--------------+ | | ... | | +--------------+--------------+--------------+--------------+ | TLV | |Sender IPv6 |Recipient IPv6| | | | ... |address, byte |address, byte | ... | | area | |No.16 (LSB) |No.1 (MSB) | | | +--------------+--------------+--------------+--------------+ | | ... | | +--------------+--------------+--------------+--------------+ | | |Recipient IPv6| | | | | ... |address, byte | Not in use | Not in use | | | |No.16 (LSB) | | | +------+--------------+--------------+--------------+--------------+ Figure 4: Type = 2 Tuple Structure Note: Bytes labeled "not in use" contain information related to the following tuple. 4.4. IPlir packet structure and IPlir header location The IPlir protocol can operate in three modes: transport, tunnel, and light tunnel. The transport and light tunnel modes ensure protection of the data generated by protocols above the IP level in the basic ISO OSI reference model, in particular, by the transport layer. The tunnel mode ensures protection of the entire source IP packet. The receiving end determines what mode the packet was sent in based on the Mode field value. Possible field values are shown in Table 2. Davletshina, et al. Expires 18 December 2022 [Page 17] Internet-Draft Abbreviated Title June 2022 +==================+====================================+ | Mode field value | Mode description | +==================+====================================+ | 0 | transport mode | +------------------+------------------------------------+ | 1 | light tunnel mode ("light tunnel") | +------------------+------------------------------------+ | 2 | tunnel mode ("tunnel" mode) | +------------------+------------------------------------+ | 3 | reserved for future needs | +------------------+------------------------------------+ Table 3: Table 2 - Mode Field Values 4.4.1. Transport mode In the transport mode, the IPlir header and (Type, Length, Value)- tupples follow the IP header and precede the header of the next layer (e.g., TCP, UDP, ICMP, etc.). In the IPv4 context, it means that the IPlir header is located after the IP header, including all options in the source IP packet, but before the header of the next level protocol. Figure 5 shows an example of IP packet protection using the IPlir in the transport mode. +-------------------------+ +--------------------------+ | Source IP packet | | IPlir packet | | +-------------------+ | | +--------------------+ | | | IP header |---------->| IP header | | | +-------------------+ | | +--------------------+ | | | IP packet data |-----+ | | IPlir header | | | +-------------------+ | | | +--------------------+ | +-------------------------+ | | | IPlir body | | | | | +----------------+ | | +------>| IP packet data | | | | | +----------------+ | | | +--------------------+ | | | IPlir trailer | | | +--------------------+ | +--------------------------+ Figure 5: IP Packet Protection Using IPlir in the Transport Mode In the IPv6 context, the IPlir header is addressed to the destination endpoint. Therefore, it should be placed after the Hop-by-hop, Routing, and Fragmentation extension headers. The Destination Options extension headers can be located before, after, or on both Davletshina, et al. Expires 18 December 2022 [Page 18] Internet-Draft Abbreviated Title June 2022 sides of the IPlir header, depending on the required semantics. However, since the IPlir protocol can ensure privacy of only the fields following the IPlir header, the recipient options should follow the IPlir header. 4.4.2. Light tunnel Location of the IPlir header and (Type, Length, Value)-tuples in the light tunnel mode is the same as in the transport mode, except that the set of tuples in the IPlir body must include type 1 tuple (two IPv4 addresses) or type 2 tuple (two IPv6 addresses), wherein the sender and recipient's addresses from the IP header of the source IP packet. The tuple type is dictated by the version of the IP header of the source IP packet. The recipient host can restore the initial IP addresses from the available tuple Value field. Unlike the transport mode, the light tunnel mode makes it possible to change addresses in the IPlir packet IP header. Figure 6 shows an example of IP packet protection using the IPlir in the light tunnel mode. Davletshina, et al. Expires 18 December 2022 [Page 19] Internet-Draft Abbreviated Title June 2022 +--------------------------+ +------------------------------+ | Source IP packet | | IPlir packet | | +--------------------+ | | +------------------------+ | | | IP header | | | | IP header | | | | +----------------+ | | | | +--------------------+ | | | | | Source IP | | | | | | Source IP | | | | | +----------------+ |---------->| +--------------------+-------+ | | | Destination IP | | | | | | Destination IP | | | | | | +----------------+ | | | | +--------------------+ | | | | +--------------------+ | | +------------------------+ | | | | IP packet data |-----+ | | IPlir header | | | | +--------------------+ | | | +------------------------+ | | +--------------------------+ | | | IPlir body | | | | | | +--------------------+ | | | | | | | TLV | | | | | | | | +----------------+ | | | | | | | | | Source IP | | | | | | | | | +----------------+<--------+ | | | | | Destination IP | | | | | | | | +----------------+ | | | | | | +--------------------+ | | +------>| IP packet data | | | | | +--------------------+ | | | +------------------------+ | | | IPlir trailer | | | +------------------------+ | +------------------------------+ Figure 6: IP Packet Protection Using IPlir in the Light Tunnel Mode 4.4.3. Tunnel mode Unlike the other modes, the tunnel mode protects the entire source IP packet, including its IP header. In the tunnel mode, a new IP header is generated with its contents based on the destination host context and the source host IP routing table, followed by the IPlir header and tuples (Type, Length, Value). This is followed by the source IP packet. Versions of the source and new IP headers can be different. It means that IPv6 packets can be transmitted via the IPv4 protocol and vice versa. Figure 7 shows an example of IP packet protection using the IPlir in the tunnel mode. Davletshina, et al. Expires 18 December 2022 [Page 20] Internet-Draft Abbreviated Title June 2022 +-------------------------+ +--------------------------+ | Source IP packet | | IPlir packet | | +-------------------+ | | +--------------------+ | | | IP header |-------+ | | IP header | | | +-------------------+ | | | +--------------------+ | | | IP packet data |----+ | | | IPlir header | | | +-------------------+ | | | | +--------------------+ | +-------------------------+ | | | | IPlir body | | | | | | +----------------+ | | | +----->| IP header | | | | | | +----------------+ | | +-------->| IP packet data | | | | | +----------------+ | | | +--------------------+ | | | IPlir trailer | | | +--------------------+ | +--------------------------+ Figure 7: IP Packet Protection Using IPlir in the Tunnel Mode 5. Security Considerations Possible values of function arguments in the algorithms above are limited by whether they can be used as conversion input parameters. 5.1. Encryption and MAC To ensure packet confidentiality, the IPlir protocol provides for a possibility to encrypt it using a symmetric cryptographic technique. Packet encryption in IPlir is recommended, but not required. Encryption can be disabled by selecting a separate cryptographic suite clearly indicating that there is no encryption. In case of encryption, it is applied between the sender and recipient hosts regardless of the transfer network topology and existence of intermediate hosts. To ensure packet integrity and authenticity of the data source, the IPlir protocol allows for MAC. Packet MAC can be end-to-end and transit. End-to-end MAC is applied between the sender and recipient hosts, and is mandatory. Transit MAC is applied between two neighbor hosts in a packet transfer chain, and is optional. To ensure both confidentiality, and integrity and authenticity of the data source of the packet at the same time, either separate encryption and MAC algorithms may be used, or AEAD algorithms to encrypt and calculate MAC simultaneously. Davletshina, et al. Expires 18 December 2022 [Page 21] Internet-Draft Abbreviated Title June 2022 5.2. Cryptographic keys It is implied that there is a key system that provides the interacting hosts with necessary exchange keys and controls their synchronization. Keys can be managed manually or automatically. The exchange keys required to process a specific packet with all their mandatory attributes (meta data) are available when packet processing starts. Correct functioning of the IPlir protocol requires a host numbering system where each host is assigned a unique identifier. Each exchange key related to the specific pair of hosts is indexed with the corresponding pair of their identifiers. Key systems where several exchange keys (not more than 16) exist simultaneously for the two hosts can be used. To make it possible, each exchange key in the IPlir protocol is additionally indexed with an integer value between 0 and 15 (inclusive) located in the KN or TKN field of the IPlir message and allowing to unambiguously determine the exchange key for the two hosts. The peculiarity of IPlir is that unique packet encryption, end-to-end MAC and transit MAC keys used in the corresponding cryptographic algorithms are derived for each IP packet based on the exchange keys. The packet encryption, end-to-end MAC, and transit MAC keys derived for the same IP packet should be different, except when AEAD algorithms are used, where one packet encryption and end-to-end MAC key is used for encryption and end-to-end MAC of the packet. The exchange key used to derive packet encryption and end-to-end MAC keys (or packet encryption and end-to-end MAC key) is determined by the KN field value of the IPlir message and identifiers of the sender and recipient hosts. The exchange key used to derive the packet transit MAC key is determined by the TKN field value of the IPlir message and identifiers of the interacting (transit) hosts. Exchange key types and methods to derive packet protection keys from them are determined by the cryptographic suite. For any unique key used in the IPlir protocol at any time it should be impossible to calculate it from the other keys, except for calculation of derived keys for packet protection from a specific exchange key. The maximum quantity of material that can be processed using the same key should be determined considering theoretical limits arising from the use of particular cryptographic algorithms and practical limitations arising during IPlir implementation. Davletshina, et al. Expires 18 December 2022 [Page 22] Internet-Draft Abbreviated Title June 2022 The maximum number of keys (packet encryption, end-to-end MAC, transit MAC keys or packet encryption and end-to-end MAC keys) derived from one exchange key should be determined considering theoretical limits arising from the use of particular cryptographic algorithms and practical limitations arising during IPlir implementation. When the allowed limit for a specific key is reached, the interacting parties should stop using it. For protection of further interactions, the parties should use a key for which the allowed limit has not been achieved, e.g., a new key. 5.3. Cryptographic suites The cryptographic algorithms and parameters used in the IPlir protocol make up a cryptographic suite designated by its CS number in the CS field of each IPlir message. There can be up to 256 different cryptographic suites in total. Permissible CS field values are provided in Table 3: +==========+=============================================+ | CS value | Description | +==========+=============================================+ | 0 | not in use | +----------+---------------------------------------------+ | 1 | MAGMA-MGM cryptographic suite | +----------+---------------------------------------------+ | 2 | KUZN-CTR-CMAC cryptographic suite | +----------+---------------------------------------------+ | 3-128 | not in use | +----------+---------------------------------------------+ | 129 | AES-128-GCM cryptographic suite | +----------+---------------------------------------------+ | 130-131 | can be used by the vendor for its own needs | +----------+---------------------------------------------+ | 132 | AES-256-CTR-CMAC cryptographic suite | +----------+---------------------------------------------+ | 133 | can be used by the vendor for its own needs | +----------+---------------------------------------------+ | 134 | AES-256-CFB-CMAC cryptographic suite | +----------+---------------------------------------------+ | 135-254 | can be used by the vendor for its own needs | +----------+---------------------------------------------+ | 255 | Not in use | +----------+---------------------------------------------+ Table 4: Permissible CS Field Values Davletshina, et al. Expires 18 December 2022 [Page 23] Internet-Draft Abbreviated Title June 2022 The list of main mechanisms and parameters defined and/or described in the cryptographic suite is shown in Table 4: +===========+===============+====================================+ | Parameter | Description | Purpose | +===========+===============+====================================+ | EncAlg | encryption | the algorithm is used to encrypt | | | algorithm | the packet | +-----------+---------------+------------------------------------+ | MACAlg | end-to-end | the algorithm is used to calculate | | | MAC algorithm | packet end-to-end MAC | +-----------+---------------+------------------------------------+ | TMACAlg | transit MAC | the algorithm is used to calculate | | | algorithm | packet transit MAC | +-----------+---------------+------------------------------------+ | MACLen | end-to-end | | | | MAC length | | +-----------+---------------+------------------------------------+ | TMACLen | transit MAC | | | | length | | +-----------+---------------+------------------------------------+ | IVLen | end-to-end | the initializing value can be used | | | initializing | for packet encryption, end-to-end | | | value length | MAC, and derivation of packet | | | | encryption keys and packet end-to- | | | | end MAC keys (or packet encryption | | | | and end-to-end MAC keys) | +-----------+---------------+------------------------------------+ | TIVLen | transit | the initializing value can be used | | | initializing | for packet transit MAC and | | | value length | derivation of packet transit MAC | | | | keys | +-----------+---------------+------------------------------------+ | KDAlg | algorithms of | the algorithms are used to derive | | | deriving | packet encryption keys and packet | | | packet | end-to-end MAC keys (or packet | | | protection | encryption and end-to-end MAC | | | keys from | keys), and to derive packet | | | exchange keys | transit MAC keys | +-----------+---------------+------------------------------------+ Table 5: Main Mechanisms And Parameters In The Cryptographic Suite All necessary parameters should be included in the cryptographic suite description. Interpretation of values of specific cryptographic suite parameters is determined by the cryptographic suite. If any parameter in the cryptographic suite is inapplicable or must be ignored, it should be specified clearly. Davletshina, et al. Expires 18 December 2022 [Page 24] Internet-Draft Abbreviated Title June 2022 5.3.1. MAGMA-MGM cryptographic suite: CS = 1 MAGMA-MGM Cryptographic Suite Description: +===========+=====================================+ | Parameter | Value | +===========+=====================================+ | EncAlg | GOST R 34.12-2015 (Magma) [RFC8891] | | | in the MGM mode [RFC9058] | +-----------+-------------------------------------+ | MACAlg | GOST R 34.12-2015 (Magma) [RFC8891] | | | in the MGM mode [RFC9058] | +-----------+-------------------------------------+ | TMACAlg | GOST R 34.12-2015 (Magma) [RFC8891] | | | in the MGM mode [RFC9058] | +-----------+-------------------------------------+ | MACLen | 32 bits | +-----------+-------------------------------------+ | TMACLen | 32 bits | +-----------+-------------------------------------+ | IVLen | 64 bits | +-----------+-------------------------------------+ | TIVLen | 64 bits | +-----------+-------------------------------------+ | KDAlg | see the description below | +-----------+-------------------------------------+ Table 6 5.3.1.1. Exchange keys For each pair of interacting hosts, there is a single exchange key with a length of 256 bits used for deriving of packet encryption and end-to-end MAC keys, as well as packet transit MAC keys. There may be several exchange keys for a pair of interacting hosts. The KN field value of the IPlir message (for derivation of packet encryption and end-to-end MAC keys) or the TKN field value of the IPlir message (for derivation of packet transit MAC keys) is used to determine a specific single exchange key. 5.3.1.2. Requirements for initializing values The end-to-end initializing value InitValue in the InitValue field of the IPlir message should have a length of 64 bits and be unique for each IPlir packet the encryption and end-to-end MAC of which are implemented by the same sender host using the same single exchange key. Davletshina, et al. Expires 18 December 2022 [Page 25] Internet-Draft Abbreviated Title June 2022 The transit initializing value TransitInitValue in the TransitInitValue field of the IPlir message should have a length of 64 bits and be unique for each IPlir packet the transit MAC of which is implemented by the same (transit) host using the same single exchange key. 5.3.1.3. Key derivation algorithms The packet encryption and end-to-end MAC key K_AEAD of-256 bit length is calculated as follows: K_AEAD = K_1 || K_2 || K_3 || K_4, where each value of K_i \in V_64, i = 1,2,3,4 is calculated as per GOST R 34.12-2015 (Magma) [RFC8891] in the CMAC mode, as per GOST R 34.13-2015 [GOST3413-2015], wherein * the single exchange key corresponding to the specified sender and recipient hosts, and the KN field value of the IPlir message is used as the key, * a binary string as shown below is used as the data: IntToVec_8(i)||Label||aL||IV_KDF||SN||Node||cL||oL, where - Label = StrToVec_48('AEAD'), - aL = IntToVec_8(LabelByteLength), where LabelByteLength = 6, - IV_KDF = InitValue, where InitValue is initialized by the InitValue field value of the IPlir message, - SN = SequenceNumber, where SequenceNumber is initialized by the SequenceNumber field value of the IPlir message, - Node = SourceIdentifier, where SourceIdentifier is initialized by the SourceIdentifier field value of the IPlir message, - cL = IntToVec_16(ContextByteLength), where ContextByteLength is the sum of byte lengths of the InitValue, SequenceNumber and SourceIdentifier fields of the IPlir message, - oL = IntToVec_16(OutputBitLength), where OutputBitLength = 256, * the MAC length s is 64 bits. The packet transit MAC key K_TMAC of 256-bit length is calculated as follows: Davletshina, et al. Expires 18 December 2022 [Page 26] Internet-Draft Abbreviated Title June 2022 K_TMAC = K_1 || K_2 || K_3 || K_4, where each value of K_i \in V_64, i = 1,2,3,4 is calculated as per GOST 34.12-2018 GOST R 34.12-2015 (Magma) [RFC8891] in the CMAC mode, as per GOST R 34.13-2015 [GOST3413-2015], wherein * the single exchange key corresponding to the specified (transit) hosts the IPlir packet passes through and the TKN field value of the IPlir message is used as the key, * a binary string as shown below is used as the data: IntToVec_8(i)||Label||aL||TIV_KDF||SN||Node||cL||oL, where - Label = StrToVec_48('TMAC'), - aL = IntToVec_8(LabelByteLength), where LabelByteLength = 6, - TIV_KDF = TransitInitValue, where TransitInitValue is initialized by the TransitInitValue field value of the IPlir message, - SN = SequenceNumber, where SequenceNumber is initialized by the SequenceNumber field value of the IPlir message, - Node = TransitIdentifier, where TransitIdentifier is initialized by the TransitIdentifier field value of the IPlir message, - cL = IntToVec_16(ContextByteLength), where ContextByteLength is the sum of byte lengths of the TransitInitValue, SequenceNumber and TransitIdentifier fields of the IPlir message, - oL = IntToVec_16(OutputBitLength), where OutputBitLength = 256, * the MAC length s is 64 bits. 5.3.1.4. Encryption and MAC algorithms Encryption of the IPlir body and calculation of the end-to-end MAC ICV in the IntegrityCheckValue field of the IPlir message are implemented according to the GOST R 34.12-2015 (Magma) [RFC8891] in the MGM mode [RFC9058], wherein * the packet encryption and end-to-end MAC key K_AEAD is used as the key, Davletshina, et al. Expires 18 December 2022 [Page 27] Internet-Draft Abbreviated Title June 2022 * data in the IPlir header fields in the order of their appearance in the IPlir message are used as associated authenticated data protected by MAC, * data in the IPlir body fields in the order of their appearance in the IPlir message are used as plaintext, * the value of IV_AEAD \in V_63 is used as a unique vector: - IV_AEAD = LSB_63(InitValue), - where InitValue is initialized by the InitValue field value of the IPlir message, * the MAC length s is 32 bits. The diagram of encryption and end-to-end MAC is shown in Figure 8. +-----------------------------------+ | IPlir header | | ... | | +---------------------------+ | +--------| SourceIdentifier | | | | +---------------------------+ | | | ... |--------+ | | +---------------------------+ | | +--------| SequenceNumber | | | | | +---------------------------+ | | +--------| InitValue |---------+ | | | +---------------------------+ | | | | +-----------------------------------+ | | | | IPlir body |--+ | | | +-----------------------------------+ | | | | | IPlir trailer | | | | | | ... | | | | | +-----------------------------------+ | | | | | | | v v v v +---------------------------------+ +-------------------+ | KDF based on GOST R 34.12-2015 | +------+ | GOST R 34.12-2015 | | (Magma) [RFC8891] in the CMAC |->|K_AEAD|->| (Magma) [RFC8891] | | mode according to | +------+ | in the MGM mode | |GOST R 34.13-2015 [GOST3413-2015]| | [RFC9058] | +---------------------------------+ +-------------------+ ^ | | | | | +-----------------------+ | | | Exchange keys between | | | Davletshina, et al. Expires 18 December 2022 [Page 28] Internet-Draft Abbreviated Title June 2022 | source and destination| | | | hosts | | | +-----------------------+ | | | | +-----------------------------------+ | | | IPlir header | | | | ... | | | | +---------------------------+ | | | | | SourceIdentifier | | | | | +---------------------------+ | | | | ... | | | | +---------------------------+ | | | | | SequenceNumber | | | | | +---------------------------+ | | | | | InitValue | | | | | +---------------------------+ | | | +-----------------------------------+ | | | Encrypted IPlir body |<--+ | +-----------------------------------+ | | IPlir trailer | | | +---------------------------+ | | | | InterityCheckValue |<-----------+ | +---------------------------+ | | ... | +-----------------------------------+ Figure 8: Diagram of Encryption and End-to-End MAC Using the MAGMA-MGM Cryptographic Suite Calculation of the transit MAC TICV in the TransitIntegrityCheckValue field of the IPlir message is implemented according to the GOST R 34.12-2015 (Magma) [RFC8891] in the MGM mode [RFC9058], wherein * the packet transit MAC key K_TMAC is used as the key, * data in the IPlir header fields, the encrypted IPlir body and IntegrityCheckValue, TransitIdentifier, TransitInitValue fields data in the order of their appearance in the IPlir message are used as associated authenticated data protected by MAC, * plaintext is an empty string, * the value of TIV_AEAD \in V_63 is used as a unique vector: - TIV_AEAD = LSB_63(TransitInitValue), - where TransitInitValue is initialized by the TransitInitValue field value of the IPlir message, Davletshina, et al. Expires 18 December 2022 [Page 29] Internet-Draft Abbreviated Title June 2022 * the MAC length s is 32 bits. The diagram of transit MAC is shown in Figure 9. The "null" value means an empty binary string. +-----------------------------------+--+ | IPlir header | | | ... | | | +---------------------------+ | | +--------| SequenceNumber | | | | | +---------------------------+ | | | | ... | | | +-----------------------------------+ | | | Encrypted IPlir body | |-------+ | +-----------------------------------+ | | | | IPlir trailer | | | | | ... | | | | | +---------------------------+ | | | +--------| TransitIdentifier | | | | | | +---------------------------+ | | | +--------| | | | | | | | TransitInitValue | | | | | | +-| | | | | | | | +---------------------------+---|--+ | | | | ... | | | +-|---------------------------------+ | | | | | +--------------------------------------+ | | +------+ | | | | null |----+ | | | +------+ | | | v v v v +---------------------------------+ +-------------------+ | KDF based on GOST R 34.12-2015 | +------+ | GOST R 34.12-2015 | | (Magma) [RFC8891] in the CMAC |->|K_TMAC|->| (Magma) [RFC8891] | | mode according to | +------+ | in the MGM mode | |GOST R 34.13-2015 [GOST3413-2015]| | [RFC9058] | +---------------------------------+ +-------------------+ ^ | | | v | +-----------------------+ +------+ | | Exchange keys between | | null | | | transit hosts | +------+ | +-----------------------+ | | +-----------------------------------+ | | IPlir header | | | ... | | Davletshina, et al. Expires 18 December 2022 [Page 30] Internet-Draft Abbreviated Title June 2022 | +---------------------------+ | | | | SequenceNumber | | | | +---------------------------+ | | | ... | | +-----------------------------------+ | | Encrypted IPlir body | | +-----------------------------------+ | | IPlir trailer | | | ... | | | +---------------------------+ | | | | TransitIdentifier | | | | +---------------------------+ | | | | | | | | | TransitInitValue | | | | | | | | | +---------------------------+ | | | | TransitInterityCheckValue |<-----------+ | +---------------------------+ | +-----------------------------------+ Figure 9: Diagram of Transit MAC Using the MAGMA-MGM Cryptographic Suite 5.3.2. KUZN-CTR-CMAC cryptographic suite: CS=2 AES-256-CTR-CMAC Cryptographic Suite Description: Davletshina, et al. Expires 18 December 2022 [Page 31] Internet-Draft Abbreviated Title June 2022 +===========+==========================================+ | Parameter | Value | +===========+==========================================+ | EncAlg | GOST R 34.12-2015 (Kuznyechik) [RFC7801] | | | in the CTR mode [GOST3413-2015] | +-----------+------------------------------------------+ | MACAlg | GOST R 34.12-2015 (Kuznyechik) [RFC7801] | | | in the CMAC mode [GOST3413-2015] | +-----------+------------------------------------------+ | TMACAlg | GOST R 34.12-2015 (Kuznyechik) [RFC7801] | | | in the CMAC mode [GOST3413-2015] | +-----------+------------------------------------------+ | MACLen | 64 bits | +-----------+------------------------------------------+ | TMACLen | 64 bits | +-----------+------------------------------------------+ | IVLen | 64 bits | +-----------+------------------------------------------+ | TIVLen | 64 bits | +-----------+------------------------------------------+ | KDAlg | see the description below | +-----------+------------------------------------------+ Table 7 5.3.2.1. Exchange keys For each pair of interacting hosts, there is a single exchange key with a length of 256 bits designed for derivation of packet encryption keys, end-to-end MAC keys, and transit MAC keys. There may be several exchange keys for a pair of interacting hosts. The KN field value of the IPlir message (for derivation of packet encryption keys and packet end-to-end MAC keys) or the TKN field value of the IPlir message (for derivation of packet transit MAC keys) is used to determine a specific single exchange key. 5.3.2.2. Requirements for initializing values The end-to-end initializing value InitValue in the InitValue field of the IPlir message should have a length of 64 bits and be unique for each IPlir packet the encryption and end-to-end MAC of which are implemented by the same sender host using the same single exchange key. Davletshina, et al. Expires 18 December 2022 [Page 32] Internet-Draft Abbreviated Title June 2022 The transit initializing value TransitInitValue in the TransitInitValue field of the IPlir message should have a length of 64 bits and be unique for each IPlir packet the transit MAC of which is implemented by the same (transit) host using the same single exchange key. 5.3.2.3. Key derivation algorithms The packet encryption key K_ENC of 256-bit length and the packet end- to-end MAC key K_MAC of 256-bit length are calculated as follows: K_ENC = K_1 || K_2, K_MAC = K_3 || K_4, where each value of K_i \in V_128, i = 1,2,3,4 is calculated as per GOST R 34.12-2015 (Kuznyechik) [RFC7801] in the CMAC mode [GOST3413-2015], wherein * the single exchange key corresponding to the specified sender and recipient hosts, and the KN field value of the IPlir message is used as the key, * a binary string as shown below is used as the data: IntToVec_8(i)||Label||aL||IV_KDF||SN||Node||cL||oL, where - Label = StrToVec_48('ENCMAC'), - aL = IntToVec_8(LabelByteLength), where LabelByteLength = 6, - IV_KDF = InitValue, where InitValue is initialized by the InitValue field value of the IPlir message, - SN = SequenceNumber, where SequenceNumber is initialized by the SequenceNumber field value of the IPlir message, - Node = SourceIdentifier, where SourceIdentifier is initialized by the SourceIdentifier field value of the IPlir message, - cL = IntToVec_16(ContextByteLength), where ContextByteLength is the sum of byte lengths of the InitValue, SequenceNumber and SourceIdentifier fields of the IPlir message, - oL = IntToVec_16(OutputBitLength), where OutputBitLength = 512, * the MAC length s is 128 bits. Davletshina, et al. Expires 18 December 2022 [Page 33] Internet-Draft Abbreviated Title June 2022 The packet transit MAC key K_TMAC of 256-bit length is calculated as follows: K_TMAC = K_1 || K_2, where each value of K_i \in V_128, i = 1,2 is calculated as per GOST R 34.12-2015 (Kuznyechik) [RFC7801] in the CMAC mode [GOST3413-2015], wherein * the single exchange key corresponding to the specified (transit) hosts the IPlir packet passes through and the TKN field value of the IPlir message is used as the key, * a binary string as shown below is used as the data: IntToVec_8(i)||Label||aL||TIV_KDF||SN||Node||cL||oL, where - Label = StrToVec_48('TMAC'), - aL = IntToVec_8(LabelByteLength), where LabelByteLength = 6, - TIV_KDF = TransitInitValue, where TransitInitValue is initialized by the TransitInitValue field value of the IPlir message, - SN = SequenceNumber, where SequenceNumber is initialized by the SequenceNumber field value of the IPlir message, - Node = TransitIdentifier, where TransitIdentifier is initialized by the TransitIdentifier field value of the IPlir message, - cL = IntToVec_16(ContextByteLength), where ContextByteLength is the sum of byte lengths of the TransitInitValue, SequenceNumber and TransitIdentifier fields of the IPlir message, - oL = IntToVec_16(OutputBitLength), where OutputBitLength = 256, * the MAC length s is 128 bits. 5.3.2.4. Encryption and MAC algorithms The IPlir body is encrypted according to the GOST R 34.12-2015 (Kuznyechik) [RFC7801] in the CTR mode [GOST3413-2015], wherein * the packet encryption key K_ENC is used as the key, * data in the IPlir body fields in the order of their appearance in the IPlir message are used as plaintext, Davletshina, et al. Expires 18 December 2022 [Page 34] Internet-Draft Abbreviated Title June 2022 * the value of IV_ENC \in V_64 is used as the initializing value: - IV_ENC = InitValue, - where InitValue is initialized by the InitValue field value of the IPlir message, * the s key stream block length is 128 bits. Calculation of the end-to-end MAC ICV in the IntegrityCheckValue field of the IPlir message is implemented according to the GOST R 34.12-2015 (Kuznyechik) [RFC7801] in the CMAC mode [GOST3413-2015], wherein * the packet end-to-end MAC key K_MAC is used as the key, * data in the IPlir body fields in the order of their appearance in the IPlir message are used as plaintext, * the MAC length s is 64 bits. The diagram of encryption and end-to-end MAC is shown in Figure 10. +-----------------------------------+ | IPlir header | | ... | | +---------------------------+ | +--------| SourceIdentifier | | | | +---------------------------+ | | | ... | | | +---------------------------+ | +--------| SequenceNumber | | | | +---------------------------+ | +--------| InitValue |----------+ | | +---------------------------+ | | | +-----------------------------------+ | | | IPlir body |--+ | | +-----------------------------------+ | | | | IPlir trailer | | | | | ... | | | | +-----------------------------------+ | | | | | v v v +---------------------------------+ +------+ +-------------------+ | KDF based on GOST R 34.12-2015 |->|K_ENC |->| GOST R 34.12-2015 | | (Kuznyechik) [RFC7801] in the | +------+ | (Kuznyechik) | | CMAC mode according to | | [RFC7801] in the | |GOST R 34.13-2015 [GOST3413-2015]| +------+ | CTR mode | Davletshina, et al. Expires 18 December 2022 [Page 35] Internet-Draft Abbreviated Title June 2022 | |->|K_MAC | | [GOST3413-2015] | +---------------------------------+ +------+ +-------------------+ ^ | | | v | +-----------------------+ +-------------------+ | | Exchange keys between | | GOST R 34.12-2015 | | | source and destination| +---| (Kuznyechik) | | | hosts | | | [RFC7801] in the | | +-----------------------+ | | CMAC mode | | | | [GOST3413-2015] | | | +-------------------+ | +-----------------------+ ^ | | | | | +---------------------------------+ | | | | | | +---+-----------------------------------+ | | | | | IPlir header | | | | | | ... | | | | | | +---------------------------+ | | | | | | | SourceIdentifier | | | | | | | +---------------------------+ | | | | | | ... | | | +---| | +---------------------------+ | | | | | | SequenceNumber | | | | | | +---------------------------+ | | | | | | InitValue | | | | | | +---------------------------+ | | | | +-----------------------------------+ | | | | Encrypted IPlir body |<---+ | +---+-----------------------------------+ | | IPlir trailer | | | +---------------------------+ | +-------------->| InterityCheckValue | | | +---------------------------+ | | ... | +-----------------------------------+ Figure 10: Diagram of Encryption and End-to-End MAC Using the KUZN-CTR-CMAC Cryptographic Suite Calculation of the transit MAC TICV in the TransitIntegrityCheckValue field of the IPlir message is implemented according to the GOST R 34.12-2015 (Kuznyechik) [RFC7801] in the CMAC mode [GOST3413-2015], wherein * the packet transit MAC key K_TMAC is used as the key, Davletshina, et al. Expires 18 December 2022 [Page 36] Internet-Draft Abbreviated Title June 2022 * data in the IPlir header fields, the encrypted IPlir body and IntegrityCheckValue, TransitIdentifier, TransitInitValue fields data in the order of their appearance in the IPlir message are used as associated authenticated data protected by MAC, * the MAC length s is 64 bits. The diagram of transit MAC is shown in Figure 11. +-----------------------------------+--+ | IPlir header | | | ... | | | +---------------------------+ | | +--------| SequenceNumber | | | | | +---------------------------+ | | | | ... | | | +-----------------------------------+ | | | Encrypted IPlir body | |---+ | +-----------------------------------+ | | | | IPlir trailer | | | | | ... | | | | | +---------------------------+ | | | +--------| TransitIdentifier | | | | | | +---------------------------+ | | | +--------| | | | | | | | TransitInitValue | | | | | | | | | | | | | +---------------------------+---|--+ | | | ... | | | +-----------------------------------+ | | | v v +---------------------------------+ +-------------------+ | KDF based on GOST R 34.12-2015 | +------+ | GOST R 34.12-2015 | | (Kuznyechik) [RFC7801] in the |->|K_TMAC|->| (Kuznyechik) | | CMAC mode according to | +------+ | [RFC7801] in the | |GOST R 34.13-2015 [GOST3413-2015]| | CMAC mode | +---------------------------------+ | [GOST3413-2015] + ^ +-------------------+ | | | | +-----------------------+ | | Exchange keys between | | | transit hosts | | +-----------------------+ | | +-----------------------------------+ | | IPlir header | | Davletshina, et al. Expires 18 December 2022 [Page 37] Internet-Draft Abbreviated Title June 2022 | ... | | | +---------------------------+ | | | | SequenceNumber | | | | +---------------------------+ | | | ... | | +-----------------------------------+ | | Encrypted IPlir body | | +-----------------------------------+ | | IPlir trailer | | | ... | | | +---------------------------+ | | | | TransitIdentifier | | | | +---------------------------+ | | | | | | | | | TransitInitValue | | | | | | | | | +---------------------------+ | | | | TransitInterityCheckValue |<-------+ | +---------------------------+ | +-----------------------------------+ Figure 11: Diagram of Transit MAC Using the KUZN-CTR-CMAC Cryptographic Suite 5.3.3. AES-128-GCM cryptographic suite: CS = 129 AES-128-GCM Cryptographic Suite Description: Davletshina, et al. Expires 18 December 2022 [Page 38] Internet-Draft Abbreviated Title June 2022 +===========+================================+ | Parameter | Value | +===========+================================+ | EncAlg | AES-128 [NIST.FIPS.197] in the | | | GCM mode [NIST.SP.800-38d] | +-----------+--------------------------------+ | MACAlg | AES-128 [NIST.FIPS.197] in the | | | GCM mode [NIST.SP.800-38d] | +-----------+--------------------------------+ | TMACAlg | AES-128 [NIST.FIPS.197] in the | | | GCM mode [NIST.SP.800-38d] | +-----------+--------------------------------+ | MACLen | 64 bits | +-----------+--------------------------------+ | TMACLen | 64 bits | +-----------+--------------------------------+ | IVLen | 96 bits | +-----------+--------------------------------+ | TIVLen | 96 bits | +-----------+--------------------------------+ | KDAlg | see the description below | +-----------+--------------------------------+ Table 8 5.3.3.1. Exchange keys For each pair of interacting hosts, there is a single exchange key with a length of 128 bits used for deriving of packet encryption and end-to-end MAC keys, as well as packet transit MAC keys. There may be several exchange keys for a pair of interacting hosts. The KN field value of the IPlir message (for derivation of packet encryption and end-to-end MAC keys) or the TKN field value of the IPlir message (for derivation of packet transit MAC keys) is used to determine a specific single exchange key. 5.3.3.2. Requirements for initializing values The end-to-end initializing value InitValue in the InitValue field of the IPlir message should have a length of 96 bits and be unique for each IPlir packet the encryption and end-to-end MAC of which are implemented by the same sender host using the same single exchange key. Davletshina, et al. Expires 18 December 2022 [Page 39] Internet-Draft Abbreviated Title June 2022 The transit initializing value TransitInitValue in the TransitInitValue field of the IPlir message should have a length of 96 bits and be unique for each IPlir packet the transit MAC of which is implemented by the same (transit) host using the same single exchange key. 5.3.3.3. Key derivation algorithms The packet encryption and end-to-end MAC key K_AEAD of-256 bit length is calculated as follows: K_AEAD = K_1, where value of K_1 \in V_128 is calculated as per KDF in Counter Mode [NIST.SP.800-108] using AES-128 [NIST.FIPS.197] in the CMAC mode [NIST.SP.800-38b] as the PRF, wherein * the single exchange key corresponding to the specified sender and recipient hosts, and the KN field value of the IPlir message is used as the key for the PRF, * a binary string as shown below is used as the input data for the PRF: IntToVec_8(i)||Label||aL||IV_KDF||SN||Node||cL||oL, where - Label = StrToVec_48('AEAD'), - aL = IntToVec_8(LabelByteLength), where LabelByteLength = 6, - IV_KDF = InitValue, where InitValue is initialized by the InitValue field value of the IPlir message, - SN = SequenceNumber, where SequenceNumber is initialized by the SequenceNumber field value of the IPlir message, - Node = SourceIdentifier, where SourceIdentifier is initialized by the SourceIdentifier field value of the IPlir message, - cL = IntToVec_16(ContextByteLength), where ContextByteLength is the sum of byte lengths of the InitValue, SequenceNumber and SourceIdentifier fields of the IPlir message, - oL = IntToVec_8(OutputBitLength), where OutputBitLength = 128, * the PRF output length is 128 bits. The packet transit MAC key K_TMAC of 128-bit length is calculated as follows: Davletshina, et al. Expires 18 December 2022 [Page 40] Internet-Draft Abbreviated Title June 2022 K_TMAC = K_1, where value of K_1 \in V_128 is calculated as per KDF in Counter Mode [NIST.SP.800-108] using AES-128 [NIST.FIPS.197] in the CMAC mode [NIST.SP.800-38b] as the PRF, wherein * the single exchange key corresponding to the specified (transit) hosts the IPlir packet passes through and the TKN field value of the IPlir message is used as the key for the PRF, * a binary string as shown below is used as the input data for the PRF: IntToVec_8(i)||Label||aL||TIV_KDF||SN||Node||cL||oL, where - Label = StrToVec_48('TMAC'), - aL = IntToVec_8(LabelByteLength), where LabelByteLength = 6, - TIV_KDF = TransitInitValue, where TransitInitValue is initialized by the TransitInitValue field value of the IPlir message, - SN = SequenceNumber, where SequenceNumber is initialized by the SequenceNumber field value of the IPlir message, - Node = TransitIdentifier, where TransitIdentifier is initialized by the TransitIdentifier field value of the IPlir message, - cL = IntToVec_16(ContextByteLength), where ContextByteLength is the sum of byte lengths of the TransitInitValue, SequenceNumber and TransitIdentifier fields of the IPlir message, - oL = IntToVec_8(OutputBitLength), where OutputBitLength = 128, * the PRF output length is 128 bits. 5.3.3.4. Encryption and MAC algorithms Encryption of the IPlir body and calculation of the end-to-end MAC ICV in the IntegrityCheckValue field of the IPlir message are implemented according to the AES-128 [NIST.FIPS.197] in the GCM mode [NIST.SP.800-38d], wherein * the packet encryption and end-to-end MAC key K_AEAD is used as the key, Davletshina, et al. Expires 18 December 2022 [Page 41] Internet-Draft Abbreviated Title June 2022 * data in the IPlir header fields in the order of their appearance in the IPlir message are used as associated authenticated data protected by MAC, * data in the IPlir body fields in the order of their appearance in the IPlir message are used as plaintext, * the value of IV_AEAD \in V_96 is used as a unique vector: - IV_AEAD = InitValue, - where InitValue is initialized by the InitValue field value of the IPlir message, * the MAC length s is 64 bits. The diagram of encryption and end-to-end MAC is shown in Figure 12. +-----------------------------------+ | IPlir header | | ... | | +---------------------------+ | +--------| SourceIdentifier | | | | +---------------------------+ | | | ... |--------+ | | +---------------------------+ | | +--------| SequenceNumber | | | | | +---------------------------+ | | +--------| InitValue |---------+ | | | +---------------------------+ | | | | +-----------------------------------+ | | | | IPlir body |--+ | | | +-----------------------------------+ | | | | | IPlir trailer | | | | | | ... | | | | | +-----------------------------------+ | | | | | | | v v v v +---------------------------------+ +-------------------+ | KDF in Counter Mode | +------+ | AES-128 | | [NIST.SP.800-108] based on |->|K_AEAD|->| [NIST.FIPS.197] | | AES-128 [NIST.FIPS.197] in the | +------+ | in the GCM mode | | CMAC mode [NIST.SP.800-38b] | | [NIST.SP.800-38d] | +---------------------------------+ +-------------------+ ^ | | | | | +-----------------------+ | | | Exchange keys between | | | Davletshina, et al. Expires 18 December 2022 [Page 42] Internet-Draft Abbreviated Title June 2022 | source and destination| | | | hosts | | | +-----------------------+ | | | | +-----------------------------------+ | | | IPlir header | | | | ... | | | | +---------------------------+ | | | | | SourceIdentifier | | | | | +---------------------------+ | | | | ... | | | | +---------------------------+ | | | | | SequenceNumber | | | | | +---------------------------+ | | | | | InitValue | | | | | +---------------------------+ | | | +-----------------------------------+ | | | Encrypted IPlir body |<--+ | +-----------------------------------+ | | IPlir trailer | | | +---------------------------+ | | | | InterityCheckValue |<-----------+ | +---------------------------+ | | ... | +-----------------------------------+ Figure 12: Figure 12 - Diagram of Encryption and End-to-End MAC Using the AES- 128-GCM Cryptographic Suite Calculation of the transit MAC TICV in the TransitIntegrityCheckValue field of the IPlir message is implemented according to the AES-128 [NIST.FIPS.197] in the GCM mode [NIST.SP.800-38d], wherein * the packet transit MAC key K_TMAC is used as the key, * data in the IPlir header fields, the encrypted IPlir body and IntegrityCheckValue, TransitIdentifier, TransitInitValue fields data in the order of their appearance in the IPlir message are used as associated authenticated data protected by MAC, * plaintext is an empty string, * the value of TIV_AEAD \in V_96 is used as a unique vector: - TIV_AEAD = TransitInitValue, - where TransitInitValue is initialized by the TransitInitValue field value of the IPlir message, Davletshina, et al. Expires 18 December 2022 [Page 43] Internet-Draft Abbreviated Title June 2022 * the MAC length s is 64 bits. The diagram of transit MAC is shown in Figure 13. The "null" value means an empty binary string. +-----------------------------------+--+ | IPlir header | | | ... | | | +---------------------------+ | | +--------| SequenceNumber | | | | | +---------------------------+ | | | | ... | | | +-----------------------------------+ | | | Encrypted IPlir body | |-------+ | +-----------------------------------+ | | | | IPlir trailer | | | | | ... | | | | | +---------------------------+ | | | +--------| TransitIdentifier | | | | | | +---------------------------+ | | | +--------| | | | | | | | TransitInitValue | | | | | | +-| | | | | | | | +---------------------------+---|--+ | | | | ... | | | +-|---------------------------------+ | | | | | +--------------------------------------+ | | +------+ | | | | null |----+ | | | +------+ | | | v v v v +---------------------------------+ +-------------------+ | KDF in Counter Mode | +------+ | AES-128 | | [NIST.SP.800-108] based on |->|K_TMAC|->| [NIST.FIPS.197] | | AES-128 [NIST.FIPS.197] in the | +------+ | in the GCM mode | | CMAC mode [NIST.SP.800-38b] | | [NIST.SP.800-38d] | +---------------------------------+ +-------------------+ ^ | | | v | +-----------------------+ +------+ | | Exchange keys between | | null | | | transit hosts | +------+ | +-----------------------+ | | +-----------------------------------+ | | IPlir header | | | ... | | Davletshina, et al. Expires 18 December 2022 [Page 44] Internet-Draft Abbreviated Title June 2022 | +---------------------------+ | | | | SequenceNumber | | | | +---------------------------+ | | | ... | | +-----------------------------------+ | | Encrypted IPlir body | | +-----------------------------------+ | | IPlir trailer | | | ... | | | +---------------------------+ | | | | TransitIdentifier | | | | +---------------------------+ | | | | | | | | | TransitInitValue | | | | | | | | | +---------------------------+ | | | | TransitInterityCheckValue |<-----------+ | +---------------------------+ | +-----------------------------------+ Figure 13: Figure 13 - Diagram of Transit MAC Using the AES-128-GCM Cryptographic Suite 5.3.4. AES-256-CTR-CMAC cryptographic suite: CS = 132 AES-256-CTR-CMAC Cryptographic Suite Description: Davletshina, et al. Expires 18 December 2022 [Page 45] Internet-Draft Abbreviated Title June 2022 +===========+================================+ | Parameter | Value | +===========+================================+ | EncAlg | AES-256 [NIST.FIPS.197] in the | | | CTR mode [NIST.SP.800-38a] | +-----------+--------------------------------+ | MACAlg | AES-256 [NIST.FIPS.197] in the | | | CMAC mode [NIST.SP.800-38b] | +-----------+--------------------------------+ | TMACAlg | AES-256 [NIST.FIPS.197] in the | | | CMAC mode [NIST.SP.800-38b] | +-----------+--------------------------------+ | MACLen | 64 bits | +-----------+--------------------------------+ | TMACLen | 64 bits | +-----------+--------------------------------+ | IVLen | 64 bits | +-----------+--------------------------------+ | TIVLen | 64 bits | +-----------+--------------------------------+ | KDAlg | see the description below | +-----------+--------------------------------+ Table 9 5.3.4.1. Exchange keys For each pair of interacting hosts, there is a single exchange key with a length of 256 bits designed for derivation of packet encryption keys, end-to-end MAC keys, and transit MAC keys. There may be several exchange keys for a pair of interacting hosts. The KN field value of the IPlir message (for derivation of packet encryption keys and packet end-to-end MAC keys) or the TKN field value of the IPlir message (for derivation of packet transit MAC keys) is used to determine a specific single exchange key. 5.3.4.2. Requirements for initializing values The end-to-end initializing value InitValue in the InitValue field of the IPlir message should have a length of 64 bits and be unique for each IPlir packet the encryption and end-to-end MAC of which are implemented by the same sender host using the same single exchange key. Davletshina, et al. Expires 18 December 2022 [Page 46] Internet-Draft Abbreviated Title June 2022 The transit initializing value TransitInitValue in the TransitInitValue field of the IPlir message should have a length of 64 bits and be unique for each IPlir packet the transit MAC of which is implemented by the same (transit) host using the same single exchange key. 5.3.4.3. Key derivation algorithms The packet encryption key K_ENC of 256-bit length and the packet end- to-end MAC key K_MAC of 256-bit length are calculated as follows: K_ENC = K_1 || K_2, K_MAC = K_3 || K_4, where each value of K_i \in V_128, i = 1,2,3,4 is calculated as per KDF in Counter Mode [NIST.SP.800-108] using AES-256 [NIST.FIPS.197] in the CMAC mode [NIST.SP.800-38b] as the PRF, wherein * the single exchange key corresponding to the specified sender and recipient hosts, and the KN field value of the IPlir message is used as the key for the PRF, * a binary string as shown below is used as the input data for the PRF: IntToVec_8(i)||Label||aL||IV_KDF||SN||Node||cL||oL, where - Label = StrToVec_48('ENCMAC'), - aL = IntToVec_8(LabelByteLength), where LabelByteLength = 6, - IV_KDF = InitValue, where InitValue is initialized by the InitValue field value of the IPlir message, - SN = SequenceNumber, where SequenceNumber is initialized by the SequenceNumber field value of the IPlir message, - Node = SourceIdentifier, where SourceIdentifier is initialized by the SourceIdentifier field value of the IPlir message, - cL = IntToVec_16(ContextByteLength), where ContextByteLength is the sum of byte lengths of the InitValue, SequenceNumber and SourceIdentifier fields of the IPlir message, - oL = IntToVec_8(OutputBitLength), where OutputBitLength = 512, * the PRF output length is 128 bits. Davletshina, et al. Expires 18 December 2022 [Page 47] Internet-Draft Abbreviated Title June 2022 The packet transit MAC key K_TMAC of 256-bit length is calculated as follows: K_TMAC = K_1 || K_2, where each value of K_i \in V_128, i = 1,2 is calculated as per KDF in Counter Mode [NIST.SP.800-108] using AES-256 [NIST.FIPS.197] in the CMAC mode [NIST.SP.800-38b] as the PRF, wherein * the single exchange key corresponding to the specified (transit) hosts the IPlir packet passes through and the TKN field value of the IPlir message is used as the key for the PRF, * a binary string as shown below is used as the input data for the PRF: IntToVec_8(i)||Label||aL||TIV_KDF||SN||Node||cL||oL, where - Label = StrToVec_48('TMAC'), - aL = IntToVec_8(LabelByteLength), where LabelByteLength = 6, - TIV_KDF = TransitInitValue, where TransitInitValue is initialized by the TransitInitValue field value of the IPlir message, - SN = SequenceNumber, where SequenceNumber is initialized by the SequenceNumber field value of the IPlir message, - Node = TransitIdentifier, where TransitIdentifier is initialized by the TransitIdentifier field value of the IPlir message, - cL = IntToVec_16(ContextByteLength), where ContextByteLength is the sum of byte lengths of the TransitInitValue, SequenceNumber and TransitIdentifier fields of the IPlir message, - oL = IntToVec_16(OutputBitLength), where OutputBitLength = 256, * the PRF output length is 128 bits. 5.3.4.4. Encryption and MAC algorithms The IPlir body is encrypted according to the AES-256 [NIST.FIPS.197] in the CTR mode [NIST.SP.800-38a], wherein * the packet encryption key K_ENC is used as the key, * data in the IPlir body fields in the order of their appearance in the IPlir message are used as plaintext, Davletshina, et al. Expires 18 December 2022 [Page 48] Internet-Draft Abbreviated Title June 2022 * the values of T_1, T_2, ... , T_n \in V_128 are used as counters in CTR mode: - T_i = InitValue || IntToVec_64(i), i = 1, 2, ... , n, - where InitValue is initialized by the InitValue field value of the IPlir message. Calculation of the end-to-end MAC ICV in the IntegrityCheckValue field of the IPlir message is implemented according to the AES-256 [NIST.FIPS.197] in the CMAC mode [NIST.SP.800-38b], wherein * the packet end-to-end MAC key K_MAC is used as the key, * data in the IPlir body fields in the order of their appearance in the IPlir message are used as plaintext, * the MAC length s is 64 bits. The diagram of encryption and end-to-end MAC is shown in Figure 14. +-----------------------------------+ | IPlir header | | ... | | +---------------------------+ | +--------| SourceIdentifier | | | | +---------------------------+ | | | ... | | | +---------------------------+ | +--------| SequenceNumber | | | | +---------------------------+ | +--------| InitValue |----------+ | | +---------------------------+ | | | +-----------------------------------+ | | | IPlir body |--+ | | +-----------------------------------+ | | | | IPlir trailer | | | | | ... | | | | +-----------------------------------+ | | | | | v v v +---------------------------------+ +------+ +-------------------+ | KDF in Counter Mode |->|K_ENC |->| AES-256 | | [NIST.SP.800-108] based on | +------+ | [NIST.FIPS.197] | | AES-256 [NIST.FIPS.197] in the | | in the CTR mode | | CMAC mode [NIST.SP.800-38b] | +------+ | [NIST.SP.800-38a] | | |->|K_MAC | | | +---------------------------------+ +------+ +-------------------+ Davletshina, et al. Expires 18 December 2022 [Page 49] Internet-Draft Abbreviated Title June 2022 ^ | | | v | +-----------------------+ +-------------------+ | | Exchange keys between | | AES-256 | | | source and destination| +---| [NIST.FIPS.197] | | | hosts | | | in the CMAC mode | | +-----------------------+ | | [NIST.SP.800-38b] | | | +-------------------+ | +-----------------------+ ^ | | | | | +---------------------------------+ | | | | | | +---+-----------------------------------+ | | | | | IPlir header | | | | | | ... | | | | | | +---------------------------+ | | | | | | | SourceIdentifier | | | | | | | +---------------------------+ | | | | | | ... | | | +---| | +---------------------------+ | | | | | | SequenceNumber | | | | | | +---------------------------+ | | | | | | InitValue | | | | | | +---------------------------+ | | | | +-----------------------------------+ | | | | Encrypted IPlir body |<---+ | +---+-----------------------------------+ | | IPlir trailer | | | +---------------------------+ | +-------------->| InterityCheckValue | | | +---------------------------+ | | ... | +-----------------------------------+ Figure 14: Figure 14 - Diagram of Encryption and End-to-End MAC Using the AES- 256-CTR-CMAC Cryptographic Suite Calculation of the transit MAC TICV in the TransitIntegrityCheckValue field of the IPlir message is implemented according to the AES-256 [NIST.FIPS.197] in the CMAC mode [NIST.SP.800-38b], wherein * the packet transit MAC key K_TMAC is used as the key, * data in the IPlir header fields, the encrypted IPlir body and IntegrityCheckValue, TransitIdentifier, TransitInitValue fields data in the order of their appearance in the IPlir message are used as associated authenticated data protected by MAC, Davletshina, et al. Expires 18 December 2022 [Page 50] Internet-Draft Abbreviated Title June 2022 * the MAC length s is 64 bits. The diagram of transit MAC is shown in Figure 15. +-----------------------------------+--+ | IPlir header | | | ... | | | +---------------------------+ | | +--------| SequenceNumber | | | | | +---------------------------+ | | | | ... | | | +-----------------------------------+ | | | Encrypted IPlir body | |---+ | +-----------------------------------+ | | | | IPlir trailer | | | | | ... | | | | | +---------------------------+ | | | +--------| TransitIdentifier | | | | | | +---------------------------+ | | | +--------| | | | | | | | TransitInitValue | | | | | | | | | | | | | +---------------------------+---|--+ | | | ... | | | +-----------------------------------+ | | | v v +---------------------------------+ +-------------------+ | KDF in Counter Mode | +------+ | AES-256 | | [NIST.SP.800-108] based on |->|K_TMAC|->| [NIST.FIPS.197] | | AES-256 [NIST.FIPS.197] in the | +------+ | in the CMAC mode | | CMAC mode [NIST.SP.800-38b] | | [NIST.SP.800-38b] | +---------------------------------+ +-------------------+ ^ | | | +-----------------------+ | | Exchange keys between | | | transit hosts | | +-----------------------+ | | +-----------------------------------+ | | IPlir header | | | ... | | | +---------------------------+ | | | | SequenceNumber | | | | +---------------------------+ | | | ... | | +-----------------------------------+ | Davletshina, et al. Expires 18 December 2022 [Page 51] Internet-Draft Abbreviated Title June 2022 | Encrypted IPlir body | | +-----------------------------------+ | | IPlir trailer | | | ... | | | +---------------------------+ | | | | TransitIdentifier | | | | +---------------------------+ | | | | | | | | | TransitInitValue | | | | | | | | | +---------------------------+ | | | | TransitInterityCheckValue |<-------+ | +---------------------------+ | +-----------------------------------+ Figure 15: Figure 15 - Diagram of Transit MAC Using the AES-256- CTR-CMAC Cryptographic Suite 5.3.5. AES-256-CFB-CMAC cryptographic suite: CS = 134 AES-256-CTR-CMAC Cryptographic Suite Description: +===========+================================+ | Parameter | Value | +===========+================================+ | EncAlg | AES-256 [NIST.FIPS.197] in the | | | CFB mode [NIST.SP.800-38a] | +-----------+--------------------------------+ | MACAlg | AES-256 [NIST.FIPS.197] in the | | | CMAC mode [NIST.SP.800-38b] | +-----------+--------------------------------+ | TMACAlg | AES-256 [NIST.FIPS.197] in the | | | CMAC mode [NIST.SP.800-38b] | +-----------+--------------------------------+ | MACLen | 64 bits | +-----------+--------------------------------+ | TMACLen | 64 bits | +-----------+--------------------------------+ | IVLen | 128 bits | +-----------+--------------------------------+ | TIVLen | 64 bits | +-----------+--------------------------------+ | KDAlg | see the description below | +-----------+--------------------------------+ Table 10 Davletshina, et al. Expires 18 December 2022 [Page 52] Internet-Draft Abbreviated Title June 2022 5.3.5.1. Exchange keys For each pair of interacting hosts, there is a single exchange key with a length of 256 bits designed for derivation of packet encryption keys, end-to-end MAC keys, and transit MAC keys. There may be several exchange keys for a pair of interacting hosts. The KN field value of the IPlir message (for derivation of packet encryption keys and packet end-to-end MAC keys) or the TKN field value of the IPlir message (for derivation of packet transit MAC keys) is used to determine a specific single exchange key. 5.3.5.2. Requirements for initializing values The end-to-end initializing value InitValue in the InitValue field of the IPlir message should have a length of 128 bits and be unique for each IPlir packet the encryption and end-to-end MAC of which are implemented by the same sender host using the same single exchange key. The transit initializing value TransitInitValue in the TransitInitValue field of the IPlir message should have a length of 64 bits and be unique for each IPlir packet the transit MAC of which is implemented by the same (transit) host using the same single exchange key. 5.3.5.3. Key derivation algorithms The packet encryption key K_ENC of 256-bit length and the packet end- to-end MAC key K_MAC of 256-bit length are calculated as follows: K_ENC = K_1 || K_2, K_MAC = K_3 || K_4, where each value of K_i \in V_128, i = 1,2,3,4 is calculated as per KDF in Counter Mode [NIST.SP.800-108] using AES-256 [NIST.FIPS.197] in the CMAC mode [NIST.SP.800-38b] as the PRF, wherein * the single exchange key corresponding to the specified sender and recipient hosts, and the KN field value of the IPlir message is used as the key for the PRF, * a binary string as shown below is used as the input data for the PRF: IntToVec_8(i)||Label||aL||IV_KDF||SN||Node||cL||oL, where - Label = StrToVec_48('ENCMAC'), Davletshina, et al. Expires 18 December 2022 [Page 53] Internet-Draft Abbreviated Title June 2022 - aL = IntToVec_8(LabelByteLength), where LabelByteLength = 6, - IV_KDF = InitValue, where InitValue is initialized by the InitValue field value of the IPlir message, - SN = SequenceNumber, where SequenceNumber is initialized by the SequenceNumber field value of the IPlir message, - Node = SourceIdentifier, where SourceIdentifier is initialized by the SourceIdentifier field value of the IPlir message, - cL = IntToVec_16(ContextByteLength), where ContextByteLength is the sum of byte lengths of the InitValue, SequenceNumber and SourceIdentifier fields of the IPlir message, - oL = IntToVec_16(OutputBitLength), where OutputBitLength = 512, * the PRF output length is 128 bits. The packet transit MAC key K_TMAC of 256-bit length is calculated as follows: K_TMAC = K_1 || K_2, where each value of K_i \in V_128, i = 1,2 is calculated as per KDF in Counter Mode [NIST.SP.800-108] using AES-256 [NIST.FIPS.197] in the CMAC mode [NIST.SP.800-38b] as the PRF, wherein * the single exchange key corresponding to the specified (transit) hosts the IPlir packet passes through and the TKN field value of the IPlir message is used as the key for the PRF, * a binary string as shown below is used as the input data for the PRF: IntToVec_8(i)||Label||aL||TIV_KDF||SN||Node||cL||oL, where - Label = StrToVec_48('TMAC'), - aL = IntToVec_8(LabelByteLength), where LabelByteLength = 6, - TIV_KDF = TransitInitValue, where TransitInitValue is initialized by the TransitInitValue field value of the IPlir message, - SN = SequenceNumber, where SequenceNumber is initialized by the SequenceNumber field value of the IPlir message, Davletshina, et al. Expires 18 December 2022 [Page 54] Internet-Draft Abbreviated Title June 2022 - Node = TransitIdentifier, where TransitIdentifier is initialized by the TransitIdentifier field value of the IPlir message, - cL = IntToVec_16(ContextByteLength), where ContextByteLength is the sum of byte lengths of the TransitInitValue, SequenceNumber and TransitIdentifier fields of the IPlir message, - oL = IntToVec_16(OutputBitLength), where OutputBitLength = 256, * the PRF output length is 128 bits. 5.3.5.4. Encryption and MAC algorithms The IPlir body is encrypted according to the AES-256 [NIST.FIPS.197] in the CFB mode [NIST.SP.800-38a], wherein * the packet encryption key K_ENC is used as the key, * data in the IPlir body fields in the order of their appearance in the IPlir message are used as plaintext, * the value of IV_ENC \in V_128 is used as the initializing value: - IV_ENC = InitValue, - where InitValue is initialized by the InitValue field value of the IPlir message. Calculation of the end-to-end MAC ICV in the IntegrityCheckValue field of the IPlir message is implemented according to the AES-256 [NIST.FIPS.197] in the CMAC mode [NIST.SP.800-38b], wherein * the packet end-to-end MAC key K_MAC is used as the key, * data in the IPlir body fields in the order of their appearance in the IPlir message are used as plaintext, * the MAC length s is 64 bits. The diagram of encryption and end-to-end MAC is shown in Figure 16. +-----------------------------------+ | IPlir header | | ... | | +---------------------------+ | +--------| SourceIdentifier | | | | +---------------------------+ | Davletshina, et al. Expires 18 December 2022 [Page 55] Internet-Draft Abbreviated Title June 2022 | | ... | | | +---------------------------+ | +--------| SequenceNumber | | | | +---------------------------+ | +--------| InitValue |----------+ | | +---------------------------+ | | | +-----------------------------------+ | | | IPlir body |--+ | | +-----------------------------------+ | | | | IPlir trailer | | | | | ... | | | | +-----------------------------------+ | | | | | v v v +---------------------------------+ +------+ +-------------------+ | KDF in Counter Mode |->|K_ENC |->| AES-256 | | [NIST.SP.800-108] based on | +------+ | [NIST.FIPS.197] | | AES-256 [NIST.FIPS.197] in the | | in the CFB mode | | CMAC mode [NIST.SP.800-38b] | +------+ | [NIST.SP.800-38a] | | |->|K_MAC | | | +---------------------------------+ +------+ +-------------------+ ^ | | | v | +-----------------------+ +-------------------+ | | Exchange keys between | | AES-256 | | | source and destination| +---| [NIST.FIPS.197] | | | hosts | | | in the CMAC mode | | +-----------------------+ | | [NIST.SP.800-38b] | | | +-------------------+ | +-----------------------+ ^ | | | | | +---------------------------------+ | | | | | | +---+-----------------------------------+ | | | | | IPlir header | | | | | | ... | | | | | | +---------------------------+ | | | | | | | SourceIdentifier | | | | | | | +---------------------------+ | | | | | | ... | | | +---| | +---------------------------+ | | | | | | SequenceNumber | | | | | | +---------------------------+ | | | | | | InitValue | | | | | | +---------------------------+ | | | | +-----------------------------------+ | | | | Encrypted IPlir body |<---+ | +---+-----------------------------------+ Davletshina, et al. Expires 18 December 2022 [Page 56] Internet-Draft Abbreviated Title June 2022 | | IPlir trailer | | | +---------------------------+ | +-------------->| InterityCheckValue | | | +---------------------------+ | | ... | +-----------------------------------+ Figure 16: Figure 16 - Diagram of Encryption and End-to-End MAC Using the AES- 256-CFB-CMAC Cryptographic Suite Calculation of the transit MAC TICV in the TransitIntegrityCheckValue field of the IPlir message is implemented according to the AES-256 [NIST.FIPS.197] in the CMAC mode [NIST.SP.800-38b], wherein * the packet transit MAC key K_TMAC is used as the key, * data in the IPlir header fields, the encrypted IPlir body and IntegrityCheckValue, TransitIdentifier, TransitInitValue fields data in the order of their appearance in the IPlir message are used as associated authenticated data protected by MAC, * the MAC length s is 64 bits. The diagram of transit MAC is shown in Figure 17. +-----------------------------------+--+ | IPlir header | | | ... | | | +---------------------------+ | | +--------| SequenceNumber | | | | | +---------------------------+ | | | | ... | | | +-----------------------------------+ | | | Encrypted IPlir body | |---+ | +-----------------------------------+ | | | | IPlir trailer | | | | | ... | | | | | +---------------------------+ | | | +--------| TransitIdentifier | | | | | | +---------------------------+ | | | +--------| | | | | | | | TransitInitValue | | | | | | | | | | | | | +---------------------------+---|--+ | | | ... | | | +-----------------------------------+ | | | v v Davletshina, et al. Expires 18 December 2022 [Page 57] Internet-Draft Abbreviated Title June 2022 +---------------------------------+ +-------------------+ | KDF in Counter Mode | +------+ | AES-256 | | [NIST.SP.800-108] based on |->|K_TMAC|->| [NIST.FIPS.197] | | AES-256 [NIST.FIPS.197] in the | +------+ | in the CMAC mode | | CMAC mode [NIST.SP.800-38b] | | [NIST.SP.800-38b] | +---------------------------------+ +-------------------+ ^ | | | +-----------------------+ | | Exchange keys between | | | transit hosts | | +-----------------------+ | | +-----------------------------------+ | | IPlir header | | | ... | | | +---------------------------+ | | | | SequenceNumber | | | | +---------------------------+ | | | ... | | +-----------------------------------+ | | Encrypted IPlir body | | +-----------------------------------+ | | IPlir trailer | | | ... | | | +---------------------------+ | | | | TransitIdentifier | | | | +---------------------------+ | | | | | | | | | TransitInitValue | | | | | | | | | +---------------------------+ | | | | TransitInterityCheckValue |<-------+ | +---------------------------+ | +-----------------------------------+ Figure 17: Figure 17 - Diagram of Transit MAC Using the AES-256- CFB-CMAC Cryptographic Suite 6. IPlir packet processing For cryptographic processing of network packets, the algorithms used and their application procedure are determined by the cryptographic suite. The cryptographic suite for protection of the source IP packet is chosen depending on the corresponding security policy of the sender host and the destination host context on the recipient end. The Davletshina, et al. Expires 18 December 2022 [Page 58] Internet-Draft Abbreviated Title June 2022 logic and procedure of processing IPlir packets protected using a certain cryptographic suite depend on the IPlir packet reception policy and the sender host context on the recipient end. The necessity and procedure of using transit MAC are determined based on the sender host security policy and IPlir packet reception policies of transit hosts and the recipient host. Depending on security policies and other requirements, protection of the recipient host or transit host against replay of previously transmitted IPlir packets for reprocessing may be required. The IPlir protocol makes it possible to arrange such protection by using counter values and/or timestamps, as well as by tracking the history of their change on transit hosts and the recipient host. As an example, SequenceNumber, InitValue, TransitInitValue field values can be used as counter values, Timestamp field values can be used as timestamps. Description of specific mechanisms designed for protection against replay of previously transmitted IPlir packets is beyond the scope of this document. 6.1. IP and IPlir packet fragmentation When packing data in IP packets, the IP protocol can fragment (break down into fragments) messages of the higher transport layer protocols UDP, TCP, etc. This processing results in several (linked) IP packets, each called an IP fragment. The IPlir protocol in transport and light tunnel modes should only be applied to whole (non-fragmented) IP packets, but not IP fragments. In the tunnel mode, the IPlir protocol can be applied to both whole IP packets and IP fragments. In case of encapsulation in IPv4, the IPlir packet, just like any other IPv4 packet, can be fragmented by routers during transmission. Before the IPlir packet is processed on the end of the recipient or transit host, the IPlir packet must be defragmented. 6.2. Source IP packet protection by the sender host If the sender host decides to protect a specific IP packet, an IPlir packet is created as follows. 1. The recipient and transit host contexts along with the applied security policy determine: * TIV_AEAD = LSB_63(TransitInitValue), * where TransitInitValue is initialized by the TransitInitValue field value of the IPlir message, Davletshina, et al. Expires 18 December 2022 [Page 59] Internet-Draft Abbreviated Title June 2022 2. Based on the recipient and transit host contexts along with the cryptographic suite: * TIV_AEAD = LSB_63(TransitInitValue), * where TransitInitValue is initialized by the TransitInitValue field value of the IPlir message, 3. The IPlir packet fields are filled in considering the data from the source IP packet and the data generated previously. 4. The IPlir body is encrypted (if required by the security policy) and the end-to-end MAC value is calculated as prescribed by the cryptographic suite. The end-to-end MAC value is placed in the corresponding field of the IPlir trailer. 5. If transit integrity control is required, the corresponding fields and flags of the IPlir header and IPlir trailer are filled in, the transit MAC value is calculated. The transit MAC value is placed in the corresponding field of the IPlir trailer. 6. An IPlir packet is generated, wherein parts of the source IP packet are located according to the rules specified in Section 4.4. 6.3. IPlir packet processing on the forward host After receiving an IPlir packet, the transit host processes the IPlir packet as follows. 1. It checks whether the received IPlir packet corresponds to the IPlir packet reception policy. If the packet does not comply with the policy, it is blocked. 2. If the IPlir version in the IPlir header is not supported by the host, the packet is blocked. 3. The IPlir packet is matched to the context of the sender host or the previous transit host. If the context is not found or contains cryptographic suites not matching the set from the IPlir header, the packet is blocked. 4. If the suite from the IPlir header does not imply transit MAC, the packet is blocked. Davletshina, et al. Expires 18 December 2022 [Page 60] Internet-Draft Abbreviated Title June 2022 5. Based on the context of the previous transit host and the IPlir header, the packet transit MAC key is derived. The IPlir packet integrity is verified by checking the transit MAC. If the transit MAC is not correct, the packet is blocked. 6. Based on the recipient host context, the next transit host is determined on the transit host (or it is determined that the IPlir packet can be delivered to the recipient host directly). If the context of the next transit host (or recipient host) is not found, the packet is blocked. 7. If the found context contains cryptographic suites not matching the set from the IPlir header, the packet is blocked. 8. Based on the context of the next transit host, IPlir header and IPlir trailer, the packet transit MAC key and transit initializing value are generated. The necessary number of the packet transit MAC key and the transit host identifier are established in the IPlir message. The transit initializing value is located in the TransitInitValue field. 9. The transit MAC value is calculated and placed in the corresponding field of the IPlir trailer. 10. An IPlir packet is generated, wherein parts of the source IP packet are located according to the rules specified in Section 4.4. There may be cases when the security policies require a transit MAC to be added to the routed packet without checking the previous value or, vice versa, the received IPlir packet integrity to be checked without calculating a new transit MAC value, as well as cases when no transit protection is required. In this case: * If no integrity verification of the received transit IPlir packet is required, steps 3, 4, 5 of the algorithm are skipped, * If no transit MAC calculation is required, steps 7, 8, 9 of the above algorithm are skipped, * If transit protection is not required, steps 3, 4, 5, 7, 8, 9 of the above algorithm are skipped. 6.4. Source IP packet recovery by the recipient host After receiving the IPlir packet, the recipient host restores the source IP packet as follows. Davletshina, et al. Expires 18 December 2022 [Page 61] Internet-Draft Abbreviated Title June 2022 1. It checks whether the received IPlir packet corresponds to the IPlir packet reception policy. If the packet does not comply with the policy, it is blocked. 2. If the IPlir version in the IPlir header is not supported by the host, the packet is blocked. 3. The IPlir packet is matched to the context of the previous transit host. If the context is not found or contains cryptographic suites not matching the set from the IPlir header, the packet is blocked. 4. Based on the context of the previous transit host and the IPlir header, the packet transit MAC key is derived. The IPlir packet integrity is verified by checking the transit MAC. If the transit MAC is not correct, the packet is blocked. 5. The IPlir packet is matched to the context of the sender host. If the context is not found or contains cryptographic suites not matching the suite from the IPlir header, the packet is blocked. 6. Based on the context of the sender host and the IPlir header, the packet encryption key and packet end-to-end MAC key are derived. 7. The end-to-end MAC is checked and, if the IPlir body was encrypted, the packet IPlir body is decrypted as defined by the cryptographic suite. If the end-to-end MAC is not correct, the packet is blocked. 8. The IP packet is restored according to the rules of Section 4.4. There may be cases when the security policies do not require transit MAC checking by the recipient host. Then steps 3, 4 of the algorithm are skipped. 7. IANA Considerations This document has no IANA actions. 8. References 8.1. Normative References [NIST.FIPS.197] NIST, "Advanced encryption standard (AES)", NIST NIST FIPS 197, DOI 10.6028/NIST.FIPS.197, November 2001, . Davletshina, et al. Expires 18 December 2022 [Page 62] Internet-Draft Abbreviated Title June 2022 [NIST.SP.800-108] Chen, L., "Recommendation for key derivation using pseudorandom functions (revised)", NIST NIST SP 800-108, DOI 10.6028/NIST.SP.800-108, 2009, . [NIST.SP.800-38a] Dworkin, M J., "Recommendation for block cipher modes of operation :methods and techniques", NIST NIST SP 800-38a, DOI 10.6028/NIST.SP.800-38a, 2001, . [NIST.SP.800-38b] Dworkin, M J., "Recommendation for block cipher modes of operation :the CMAC mode for authentication", NIST NIST SP 800-38b, DOI 10.6028/NIST.SP.800-38b, 2016, . [NIST.SP.800-38d] Dworkin, M J., "Recommendation for block cipher modes of operation :GaloisCounter Mode (GCM) and GMAC", NIST NIST SP 800-38d, DOI 10.6028/NIST.SP.800-38d, 2007, . [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, March 1997, . [RFC7801] Dolmatov, V., Ed., "GOST R 34.12-2015: Block Cipher "Kuznyechik"", RFC 7801, DOI 10.17487/RFC7801, March 2016, . [RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC 2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, May 2017, . [RFC8891] Dolmatov, V., Ed. and D. Baryshkov, "GOST R 34.12-2015: Block Cipher "Magma"", RFC 8891, DOI 10.17487/RFC8891, September 2020, . Davletshina, et al. Expires 18 December 2022 [Page 63] Internet-Draft Abbreviated Title June 2022 [RFC9058] Smyshlyaev, S., Ed., Nozdrunov, V., Shishkin, V., and E. Griboedova, "Multilinear Galois Mode (MGM)", RFC 9058, DOI 10.17487/RFC9058, June 2021, . 8.2. Informative References [GOST3413-2015] Federal Agency on Technical Regulating and Metrology, "Information technology. Cryptographic data security. Modes of operation for block ciphers", GOST R 34.13-2015, 2015. Authors' Addresses Davletshina Alexandra (editor) InfoTeCS 2B stroenie 1, ul. Otradnaya Moscow 127273 Russian Federation Phone: +7 (495) 737-61-92 Email: Aleksandra.Davletshina@infotecs.ru Urivskiy Alexey InfoTeCS 2B stroenie 1, ul. Otradnaya Moscow 127273 Russian Federation Phone: +7 (495) 737-61-92 Email: urivskiy@infotecs.ru Rybkin Andrey InfoTeCS 2B stroenie 1, ul. Otradnaya Moscow 127273 Russian Federation Phone: +7 (495) 737-61-92 Email: Andrey.Rybkin@infotecs.ru Tychina Leonid InfoTeCS 2B stroenie 1, ul. Otradnaya Davletshina, et al. Expires 18 December 2022 [Page 64] Internet-Draft Abbreviated Title June 2022 Moscow 127273 Russian Federation Phone: +7 (495) 737-61-92 Email: tychina@infotecs.ru Parshin Ilia InfoTeCS 2B stroenie 1, ul. Otradnaya Moscow 127273 Russian Federation Phone: +7 (495) 737-61-92 Email: Parshin.Ilia@infotecs.ru Davletshina, et al. Expires 18 December 2022 [Page 65]