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Crypto Forum AEAD AES stream cipher Message Authentication Code (MAC) This document describes the AEGIS-128L, AEGIS-256, AEGIS-128X, and AEGIS-256X AES-based authenticated encryption with associated data (AEAD) algorithms designed for high-performance applications. It also specifies their use as stream ciphers and message authentication codes (MACs). The document is a product of the Crypto Forum Research Group (CFRG).
Status of This Memo This document is not an Internet Standards Track specification; it is published for informational purposes. This document is a product of the Internet Research Task Force (IRTF). The IRTF publishes the results of Internet-related research and development activities. These results might not be suitable for deployment. This RFC represents the consensus of the Crypto Forum Research Group of the Internet Research Task Force (IRTF). Documents approved for publication by the IRSG are not candidates for any level of Internet Standard; see Section 2 of RFC 7841. Information about the current status of this document, any errata, and how to provide feedback on it may be obtained at .
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Table of Contents
  • .  Introduction
  • .  Conventions and Definitions
  • .  The AEGIS-128L Algorithm
    • .  Authenticated Encryption
    • .  Authenticated Decryption
    • .  The Update Function
    • .  The Init Function
    • .  The Absorb Function
    • .  The Enc Function
    • .  The Dec Function
    • .  The DecPartial Function
    • .  The Finalize Function
  • .  The AEGIS-256 Algorithm
    • .  Authenticated Encryption
    • .  Authenticated Decryption
    • .  The Update Function
    • .  The Init Function
    • .  The Absorb Function
    • .  The Enc Function
    • .  The Dec Function
    • .  The DecPartial Function
    • .  The Finalize Function
  • .  Parallel Modes
    • .  Additional Conventions and Definitions
    • .  Authenticated Encryption
    • .  Authenticated Decryption
    • .  AEGIS-128X
      • .  The Update Function
      • .  The Init Function
      • .  The Absorb Function
      • .  The Enc Function
      • .  The Dec Function
      • .  The DecPartial Function
      • .  The Finalize Function
    • .  AEGIS-256X
      • .  The Update Function
      • .  The Init Function
      • .  The Absorb Function
      • .  The Enc Function
      • .  The Dec Function
      • .  The DecPartial Function
      • .  The Finalize Function
    • .  Implementation Considerations
    • .  Operational Considerations
  • .  Encoding (ct, tag) Tuples
  • .  AEGIS as a Stream Cipher
  • .  AEGIS as a Message Authentication Code
    • .  AEGISMAC-128L
    • .  AEGISMAC-256
    • .  AEGISMAC-128X
      • .  The Mac Function
      • .  The FinalizeMac Function
    • .  AEGISMAC-256X
      • .  The Mac Function
      • .  The FinalizeMac Function
  • .  Security Considerations
    • .  Usage Guidelines
      • .  Key and Nonce Selection
      • .  Committing Security
      • .  Multi-User Security
    • .  Implementation Security
    • .  Security Guarantees
  • . IANA Considerations
  • . References
    • .  Normative References
    • .  Informative References
  • .  Test Vectors
    • .  AESRound Test Vector
    • .  AEGIS-128L Test Vectors
      • .  Update Test Vector
      • .  Test Vector 1
      • .  Test Vector 2
      • .  Test Vector 3
      • .  Test Vector 4
      • .  Test Vector 5
      • .  Test Vector 6
      • .  Test Vector 7
      • .  Test Vector 8
      • . Test Vector 9
    • .  AEGIS-256 Test Vectors
      • .  Update Test Vector
      • .  Test Vector 1
      • .  Test Vector 2
      • .  Test Vector 3
      • .  Test Vector 4
      • .  Test Vector 5
      • .  Test Vector 6
      • .  Test Vector 7
      • .  Test Vector 8
      • . Test Vector 9
    • .  AEGIS-128X2 Test Vectors
      • .  Initial State
      • .  Test Vector 1
      • .  Test Vector 2
    • .  AEGIS-128X4 Test Vectors
      • .  Initial State
      • .  Test Vector 1
      • .  Test Vector 2
    • .  AEGIS-256X2 Test Vectors
      • .  Initial State
      • .  Test Vector 1
      • .  Test Vector 2
    • .  AEGIS-256X4 Test Vectors
      • .  Initial State
      • .  Test Vector 1
      • .  Test Vector 2
    • .  AEGISMAC Test Vectors
      • .  AEGISMAC-128L Test Vector
      • .  AEGISMAC-128X2 Test Vector
      • .  AEGISMAC-128X4 Test Vector
      • .  AEGISMAC-256 Test Vector
      • .  AEGISMAC-256X2 Test Vector
      • .  AEGISMAC-256X4 Test Vector
  • Acknowledgments
  • Authors' Addresses
Introduction This document describes the AEGIS family of authenticated encryption with associated data (AEAD) algorithms , which were chosen for high-performance applications in the CAESAR (Competition for Authenticated Encryption: Security, Applicability, and Robustness) competition. Among the finalists, AEGIS-128 was chosen as the winner for this category. However, AEGIS-128L, another finalist, offers enhanced performance and a stronger security margin . Additionally, AEGIS-256, which also reached the final round, provides 256-bit security and supports higher usage limits. Therefore, this document specifies the following variants:
  • AEGIS-128L, which has a 128-bit key, a 128-bit nonce, a 1024-bit state, a 128- or 256-bit authentication tag, and processes 256-bit input blocks.
  • AEGIS-256, which has a 256-bit key, a 256-bit nonce, a 768-bit state, a 128- or 256-bit authentication tag, and processes 128-bit input blocks.
  • AEGIS-128X, which is a mode based on AEGIS-128L, specialized for CPUs with large vector registers and vector AES instructions.
  • AEGIS-256X, which is a mode based on AEGIS-256, specialized for CPUs with large vector registers and vector AES instructions.
All variants are inverse-free and constructed from the AES encryption round function . The AEGIS cipher family offers performance that significantly exceeds AES-GCM on CPUs with AES instructions. Similarly, software implementations not using AES instructions can also be faster, although to a lesser extent. Unlike with AES-GCM, nonces can be safely chosen at random with no practical limit when using AEGIS-256 and AEGIS-256X. AEGIS-128L and AEGIS-128X also allow for more messages to be safely encrypted when using random nonces. With some existing AEAD schemes, such as AES-GCM, an attacker can generate a ciphertext that successfully decrypts under multiple different keys (a partitioning oracle attack) . This ability to craft a (ciphertext, authentication tag) pair that verifies under multiple keys significantly reduces the number of required interactions with the oracle to perform an exhaustive search, making it practical if the key space is small. For example, with password-based encryption, an attacker can guess a large number of passwords at a time by recursively submitting such a ciphertext to an oracle, which speeds up a password search by reducing it to a binary search. With AEGIS, finding distinct (key, nonce) pairs that successfully decrypt a given (associated data, ciphertext, authentication tag) tuple is believed to have a complexity that depends on the tag size. A 128-bit tag provides 64-bit committing security, which is generally acceptable for interactive protocols. With a 256-bit tag, finding a collision becomes impractical. Unlike most other AES-based AEAD constructions, leaking a state does not leak the key or previous states. Finally, an AEGIS key is not required after the initialization function, and there is no key schedule. Thus, ephemeral keys can be erased from memory before any data has been encrypted or decrypted, mitigating cold boot attacks. Note that an earlier version of Hongjun Wu and Bart Preneel's paper introducing AEGIS specified AEGIS-128L and AEGIS-256 with a different Finalize function. We follow AEGIS v1.1 . This document represents the consensus of the Crypto Forum Research Group (CFRG). It is not an IETF product and is not a standard.
Conventions and Definitions 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 when, and only when, they appear in all capitals, as shown here. Throughout this document, "byte" is used interchangeably with "octet" and refers to an 8-bit sequence. Primitives:
  • {}: an empty bit array.
  • |x|: the length of x in bits.
  • a ^ b: the bitwise exclusive OR operation between a and b.
  • a & b: the bitwise AND operation between a and b.
  • a || b: the concatenation of a and b.
  • a mod b: the remainder obtained when dividing a (the dividend) by b (the divisor) using Euclidean division.
  • LE64(x): returns the little-endian encoding of unsigned 64-bit integer x.
  • Byte(x): the value x encoded as 8 bits.
  • Zeros(n): returns an n-bit array containing only zero bits.
  • ZeroPad(x, n): returns x after appending zeros until its length is a multiple of n bits. No padding is added if the length of x is already a multiple of n, including when x is empty.
  • Truncate(x, n): returns the first n bits of x.
  • Split(x, n): returns x split into n-bit blocks, ignoring partial blocks.
  • Tail(x, n): returns the last n bits of x. Tail(x, 0) returns {}.
  • AESRound(in, rk): a single round of the AES encryption round function, which is the composition of the SubBytes, ShiftRows, MixColumns, and AddRoundKey transformations, as defined in Section 5 of . Here, in is the 128-bit AES input state, and rk is the 128-bit round key.
  • Repeat(n, F): n sequential evaluations of the function F.
  • CtEq(a, b): compares a and b in constant time, returning True for an exact match and False otherwise.
AEGIS internal functions:
  • Update(M0, M1) or Update(M): the state update function.
  • Init(key, nonce): the initialization function.
  • Absorb(ai): the input block absorption function.
  • Enc(xi): the input block encryption function.
  • Dec(ci): the input block decryption function.
  • DecPartial(cn): the input block decryption function for the last ciphertext bits when they do not fill an entire block.
  • Finalize(ad_len_bits, msg_len_bits): the authentication tag generation function.
Input blocks are 256 bits for AEGIS-128L and 128 bits for AEGIS-256. AES blocks:
  • Si: the i-th AES block of the current state.
  • S'i: the i-th AES block of the next state.
  • {Si, ...Sj}: the vector of the i-th AES block of the current state to the j-th block of the current state.
  • C0: an AES block built from the following bytes in hexadecimal format: { 0x00, 0x01, 0x01, 0x02, 0x03, 0x05, 0x08, 0x0d, 0x15, 0x22, 0x37, 0x59, 0x90, 0xe9, 0x79, 0x62 }.
  • C1: an AES block built from the following bytes in hexadecimal format: { 0xdb, 0x3d, 0x18, 0x55, 0x6d, 0xc2, 0x2f, 0xf1, 0x20, 0x11, 0x31, 0x42, 0x73, 0xb5, 0x28, 0xdd }.
AES blocks are always 128 bits in length. Input and output values:
  • key: the encryption key (128 bits for AEGIS-128L, 256 bits for AEGIS-256).
  • nonce: the public nonce (128 bits for AEGIS-128L, 256 bits for AEGIS-256).
  • ad: the associated data.
  • msg: the plaintext.
  • ct: the ciphertext.
  • tag: the authentication tag (128 or 256 bits).
The AEGIS-128L Algorithm AEGIS-128L has a 1024-bit state, made of eight 128-bit blocks {S0, ...S7}. The parameters for this algorithm, as defined in , are:
  • K_LEN (key length) is 16 bytes (128 bits).
  • P_MAX (maximum length of the plaintext) is 261 - 1 bytes (264 - 8 bits).
  • A_MAX (maximum length of the associated data) is 261 - 1 bytes (264 - 8 bits).
  • N_MIN (minimum nonce length) = N_MAX (maximum nonce length) and is 16 bytes (128 bits).
  • C_MAX (maximum ciphertext length) is P_MAX + 16 bytes for a 128-bit tag or P_MAX + 32 bytes for a 256-bit tag. In bits, these limits are (264 - 8) + 128 and (264 - 8) + 256 bits, respectively.
Distinct associated data inputs, as described in , MUST be unambiguously encoded as a single input. It is up to the application to create a structure in the associated data input if needed.
Authenticated Encryption Encrypt(msg, ad, key, nonce) The Encrypt function encrypts a message and returns the ciphertext along with an authentication tag that verifies the authenticity of the message and associated data, if provided. Security:
  • For a given key, the nonce MUST NOT be reused under any circumstances; doing so allows an attacker to recover the internal state.
  • The key MUST be randomly chosen from a uniform distribution.
Inputs:
  • msg: the message to be encrypted (length MUST be less than or equal to P_MAX).
  • ad: the associated data to authenticate (length MUST be less than or equal to A_MAX).
  • key: the encryption key.
  • nonce: the public nonce.
Outputs:
  • ct: the ciphertext.
  • tag: the authentication tag.
Steps: Init(key, nonce) ct = {} ad_blocks = Split(ZeroPad(ad, 256), 256) for ai in ad_blocks: Absorb(ai) msg_blocks = Split(ZeroPad(msg, 256), 256) for xi in msg_blocks: ct = ct || Enc(xi) tag = Finalize(|ad|, |msg|) ct = Truncate(ct, |msg|) return ct and tag
Authenticated Decryption Decrypt(ct, tag, ad, key, nonce) The Decrypt function decrypts a ciphertext, verifies that the authentication tag is correct, and returns the message on success or an error if tag verification fails. Security:
  • If tag verification fails, the decrypted message and wrong authentication tag MUST NOT be given as output. The decrypted message MUST be overwritten with zeros before the function returns.
  • The comparison of the input tag with the expected_tag MUST be done in constant time.
Inputs:
  • ct: the ciphertext to decrypt (length MUST be less than or equal to P_MAX).
  • tag: the authentication tag.
  • ad: the associated data to authenticate (length MUST be less than or equal to A_MAX).
  • key: the encryption key.
  • nonce: the public nonce.
Outputs:
  • Either the decrypted message msg or an error indicating that the authentication tag is invalid for the given inputs.
Steps: Init(key, nonce) msg = {} ad_blocks = Split(ZeroPad(ad, 256), 256) for ai in ad_blocks: Absorb(ai) ct_blocks = Split(ct, 256) cn = Tail(ct, |ct| mod 256) for ci in ct_blocks: msg = msg || Dec(ci) if cn is not empty: msg = msg || DecPartial(cn) expected_tag = Finalize(|ad|, |msg|) if CtEq(tag, expected_tag) is False: erase msg erase expected_tag return "verification failed" error else: return msg
The Update Function Update(M0, M1) The Update function is the core of the AEGIS-128L algorithm. It updates the state {S0, ...S7} using two 128-bit values. Inputs:
  • M0: the first 128-bit block to be absorbed.
  • M1: the second 128-bit block to be absorbed.
Modifies:
  • {S0, ...S7}: the state.
Steps: S'0 = AESRound(S7, S0 ^ M0) S'1 = AESRound(S0, S1) S'2 = AESRound(S1, S2) S'3 = AESRound(S2, S3) S'4 = AESRound(S3, S4 ^ M1) S'5 = AESRound(S4, S5) S'6 = AESRound(S5, S6) S'7 = AESRound(S6, S7) S0 = S'0 S1 = S'1 S2 = S'2 S3 = S'3 S4 = S'4 S5 = S'5 S6 = S'6 S7 = S'7
The Init Function Init(key, nonce) The Init function constructs the initial state {S0, ...S7} using the given key and nonce. Inputs:
  • key: the encryption key.
  • nonce: the public nonce.
Defines:
  • {S0, ...S7}: the initial state.
Steps: S0 = key ^ nonce S1 = C1 S2 = C0 S3 = C1 S4 = key ^ nonce S5 = key ^ C0 S6 = key ^ C1 S7 = key ^ C0 Repeat(10, Update(nonce, key))
The Absorb Function Absorb(ai) The Absorb function absorbs a 256-bit input block ai into the state {S0, ...S7}. Inputs:
  • ai: the 256-bit input block.
Steps: t0, t1 = Split(ai, 128) Update(t0, t1)
The Enc Function Enc(xi) The Enc function encrypts a 256-bit input block xi using the state {S0, ...S7}. Inputs:
  • xi: the 256-bit input block.
Outputs:
  • ci: the 256-bit encrypted block.
Steps: z0 = S1 ^ S6 ^ (S2 & S3) z1 = S2 ^ S5 ^ (S6 & S7) t0, t1 = Split(xi, 128) out0 = t0 ^ z0 out1 = t1 ^ z1 Update(t0, t1) ci = out0 || out1 return ci
The Dec Function Dec(ci) The Dec function decrypts a 256-bit input block ci using the state {S0, ...S7}. Inputs:
  • ci: the 256-bit encrypted block.
Outputs:
  • xi: the 256-bit decrypted block.
Steps: z0 = S1 ^ S6 ^ (S2 & S3) z1 = S2 ^ S5 ^ (S6 & S7) t0, t1 = Split(ci, 128) out0 = t0 ^ z0 out1 = t1 ^ z1 Update(out0, out1) xi = out0 || out1 return xi
The DecPartial Function DecPartial(cn) The DecPartial function decrypts the last ciphertext bits cn using the state {S0, ...S7} when they do not fill an entire block. Inputs:
  • cn: the encrypted input.
Outputs:
  • xn: the decryption of cn.
Steps: z0 = S1 ^ S6 ^ (S2 & S3) z1 = S2 ^ S5 ^ (S6 & S7) t0, t1 = Split(ZeroPad(cn, 256), 128) out0 = t0 ^ z0 out1 = t1 ^ z1 xn = Truncate(out0 || out1, |cn|) v0, v1 = Split(ZeroPad(xn, 256), 128) Update(v0, v1) return xn
The Finalize Function Finalize(ad_len_bits, msg_len_bits) The Finalize function computes a 128- or 256-bit tag that authenticates the message and associated data. Inputs:
  • ad_len_bits: the length of the associated data in bits.
  • msg_len_bits: the length of the message in bits.
Outputs:
  • tag: the authentication tag.
Steps: t = S2 ^ (LE64(ad_len_bits) || LE64(msg_len_bits)) Repeat(7, Update(t, t)) if tag_len_bits == 128: tag = S0 ^ S1 ^ S2 ^ S3 ^ S4 ^ S5 ^ S6 else: # 256 bits tag = (S0 ^ S1 ^ S2 ^ S3) || (S4 ^ S5 ^ S6 ^ S7) return tag
The AEGIS-256 Algorithm AEGIS-256 has a 768-bit state, made of six 128-bit blocks {S0, ...S5}. The parameters for this algorithm, as defined in , are:
  • K_LEN (key length) is 32 bytes (256 bits).
  • P_MAX (maximum length of the plaintext) is 261 - 1 bytes (264 - 8 bits).
  • A_MAX (maximum length of the associated data) is 261 - 1 bytes (264 - 8 bits).
  • N_MIN (minimum nonce length) = N_MAX (maximum nonce length) and is 32 bytes (256 bits).
  • C_MAX (maximum ciphertext length) is P_MAX + 16 bytes for a 128-bit tag or P_MAX + 32 bytes for a 256-bit tag. In bits, these limits are (264 - 8) + 128 and (264 - 8) + 256 bits, respectively.
Distinct associated data inputs, as described in , MUST be unambiguously encoded as a single input. It is up to the application to create a structure in the associated data input if needed.
Authenticated Encryption Encrypt(msg, ad, key, nonce) The Encrypt function encrypts a message and returns the ciphertext along with an authentication tag that verifies the authenticity of the message and associated data, if provided. Security:
  • For a given key, the nonce MUST NOT be reused under any circumstances; doing so allows an attacker to recover the internal state.
  • The key MUST be randomly chosen from a uniform distribution.
Inputs:
  • msg: the message to be encrypted (length MUST be less than or equal to P_MAX).
  • ad: the associated data to authenticate (length MUST be less than or equal to A_MAX).
  • key: the encryption key.
  • nonce: the public nonce.
Outputs:
  • ct: the ciphertext.
  • tag: the authentication tag.
Steps: Init(key, nonce) ct = {} ad_blocks = Split(ZeroPad(ad, 128), 128) for ai in ad_blocks: Absorb(ai) msg_blocks = Split(ZeroPad(msg, 128), 128) for xi in msg_blocks: ct = ct || Enc(xi) tag = Finalize(|ad|, |msg|) ct = Truncate(ct, |msg|) return ct and tag
Authenticated Decryption Decrypt(ct, tag, ad, key, nonce) The Decrypt function decrypts a ciphertext, verifies that the authentication tag is correct, and returns the message on success or an error if tag verification fails. Security:
  • If tag verification fails, the decrypted message and wrong authentication tag MUST NOT be given as output. The decrypted message MUST be overwritten with zeros before the function returns.
  • The comparison of the input tag with the expected_tag MUST be done in constant time.
Inputs:
  • ct: the ciphertext to decrypt (length MUST be less than or equal to P_MAX).
  • tag: the authentication tag.
  • ad: the associated data to authenticate (length MUST be less than or equal to A_MAX).
  • key: the encryption key.
  • nonce: the public nonce.
Outputs:
  • Either the decrypted message msg or an error indicating that the authentication tag is invalid for the given inputs.
Steps: Init(key, nonce) msg = {} ad_blocks = Split(ZeroPad(ad, 128), 128) for ai in ad_blocks: Absorb(ai) ct_blocks = Split(ct, 128) cn = Tail(ct, |ct| mod 128) for ci in ct_blocks: msg = msg || Dec(ci) if cn is not empty: msg = msg || DecPartial(cn) expected_tag = Finalize(|ad|, |msg|) if CtEq(tag, expected_tag) is False: erase msg erase expected_tag return "verification failed" error else: return msg
The Update Function Update(M) The Update function is the core of the AEGIS-256 algorithm. It updates the state {S0, ...S5} using a 128-bit value. Inputs:
  • M: the 128-bit block to be absorbed.
Modifies:
  • {S0, ...S5}: the state.
Steps: S'0 = AESRound(S5, S0 ^ M) S'1 = AESRound(S0, S1) S'2 = AESRound(S1, S2) S'3 = AESRound(S2, S3) S'4 = AESRound(S3, S4) S'5 = AESRound(S4, S5) S0 = S'0 S1 = S'1 S2 = S'2 S3 = S'3 S4 = S'4 S5 = S'5
The Init Function Init(key, nonce) The Init function constructs the initial state {S0, ...S5} using the given key and nonce. Inputs:
  • key: the encryption key.
  • nonce: the public nonce.
Defines:
  • {S0, ...S5}: the initial state.
Steps: k0, k1 = Split(key, 128) n0, n1 = Split(nonce, 128) S0 = k0 ^ n0 S1 = k1 ^ n1 S2 = C1 S3 = C0 S4 = k0 ^ C0 S5 = k1 ^ C1 Repeat(4, Update(k0) Update(k1) Update(k0 ^ n0) Update(k1 ^ n1) )
The Absorb Function Absorb(ai) The Absorb function absorbs a 128-bit input block ai into the state {S0, ...S5}. Inputs:
  • ai: the 128-bit input block.
Steps: Update(ai)
The Enc Function Enc(xi) The Enc function encrypts a 128-bit input block xi using the state {S0, ...S5}. Inputs:
  • xi: the 128-bit input block.
Outputs:
  • ci: the 128-bit encrypted block.
Steps: z = S1 ^ S4 ^ S5 ^ (S2 & S3) Update(xi) ci = xi ^ z return ci
The Dec Function Dec(ci) The Dec function decrypts a 128-bit input block ci using the state {S0, ...S5}. Inputs:
  • ci: the 128-bit encrypted block.
Outputs:
  • xi: the 128-bit decrypted block.
Steps: z = S1 ^ S4 ^ S5 ^ (S2 & S3) xi = ci ^ z Update(xi) return xi
The DecPartial Function DecPartial(cn) The DecPartial function decrypts the last ciphertext bits cn using the state {S0, ...S5} when they do not fill an entire block. Inputs:
  • cn: the encrypted input.
Outputs:
  • xn: the decryption of cn.
Steps: z = S1 ^ S4 ^ S5 ^ (S2 & S3) t = ZeroPad(cn, 128) out = t ^ z xn = Truncate(out, |cn|) v = ZeroPad(xn, 128) Update(v) return xn
The Finalize Function Finalize(ad_len_bits, msg_len_bits) The Finalize function computes a 128- or 256-bit tag that authenticates the message and associated data. Inputs:
  • ad_len_bits: the length of the associated data in bits.
  • msg_len_bits: the length of the message in bits.
Outputs:
  • tag: the authentication tag.
Steps: t = S3 ^ (LE64(ad_len_bits) || LE64(msg_len_bits)) Repeat(7, Update(t)) if tag_len_bits == 128: tag = S0 ^ S1 ^ S2 ^ S3 ^ S4 ^ S5 else: # 256 bits tag = (S0 ^ S1 ^ S2) || (S3 ^ S4 ^ S5) return tag
Parallel Modes Some CPUs, such as Intel and Intel-compatible CPUs with the Vectorized AES (VAES) extensions, include instructions to efficiently apply the AES round function to a vector of AES blocks. AEGIS-128X and AEGIS-256X are optional, specialized modes designed to take advantage of these instructions. They share the same properties as the ciphers they are based on but can be significantly faster on these platforms, even for short messages. AEGIS-128X and AEGIS-256X are parallel evaluations of multiple AEGIS-128L and AEGIS-256 instances, respectively, with distinct initial states. On CPUs with wide vector registers, different states can be stored in different 128-bit lanes of the same vector register, allowing parallel updates using vector instructions. The modes are parameterized by the parallelism degree. With 256-bit registers, two parallel operations can be applied to 128-bit AES blocks. With 512-bit registers, the number of instances can be raised to four. The state of a parallel mode is represented as a vector of AEGIS-128L or AEGIS-256 states.
Additional Conventions and Definitions
  • D: the degree of parallelism.
  • R: the absorption and output rate of the mode. With AEGIS-128X, the rate is 256 * D bits. With AEGIS-256X, the rate is 128 * D bits.
  • V[j,i]: the j-th AES block of the i-th state. i is in the [0..D) range. For AEGIS-128X, j is in the [0..8) range, while for AEGIS-256X, j is in the [0..6) range.
  • V'[j,i]: the j-th AES block of the next i-th state.
  • ctx[i]: the i-th context separator. This is a 128-bit mask made of a byte representing the state index, followed by a byte representing the highest index and 112 all-zero bits.
Authenticated Encryption Encrypt(msg, ad, key, nonce) The Encrypt function of AEGIS-128X resembles that of AEGIS-128L. Similarly, the Encrypt function of AEGIS-256X mirrors that of AEGIS-256. However, both process R-bit input blocks per update. Steps: Init(key, nonce) ct = {} ad_blocks = Split(ZeroPad(ad, R), R) for ai in ad_blocks: Absorb(ai) msg_blocks = Split(ZeroPad(msg, R), R) for xi in msg_blocks: ct = ct || Enc(xi) tag = Finalize(|ad|, |msg|) ct = Truncate(ct, |msg|) return ct and tag
Authenticated Decryption Decrypt(ct, tag, ad, key, nonce) The Decrypt function of AEGIS-128X resembles that of AEGIS-128L. Similarly, the Decrypt function of AEGIS-256X mirrors that of AEGIS-256. However, both process R-bit input blocks per update. Steps: Init(key, nonce) msg = {} ad_blocks = Split(ZeroPad(ad, R), R) for ai in ad_blocks: Absorb(ai) ct_blocks = Split(ct, R) cn = Tail(ct, |ct| mod R) for ci in ct_blocks: msg = msg || Dec(ci) if cn is not empty: msg = msg || DecPartial(cn) expected_tag = Finalize(|ad|, |msg|) if CtEq(tag, expected_tag) is False: erase msg erase expected_tag return "verification failed" error else: return msg
AEGIS-128X
The Update Function Update(M0, M1) The AEGIS-128X Update function is similar to the AEGIS-128L Update function but absorbs R (= 256 * D) bits at once. M0 and M1 are 128 * D bits instead of 128 bits, but they are split into 128-bit blocks, each of which updates a different AEGIS-128L state. Steps: m0 = Split(M0, 128) m1 = Split(M1, 128) for i in 0..D: V'[0,i] = AESRound(V[7,i], V[0,i] ^ m0[i]) V'[1,i] = AESRound(V[0,i], V[1,i]) V'[2,i] = AESRound(V[1,i], V[2,i]) V'[3,i] = AESRound(V[2,i], V[3,i]) V'[4,i] = AESRound(V[3,i], V[4,i] ^ m1[i]) V'[5,i] = AESRound(V[4,i], V[5,i]) V'[6,i] = AESRound(V[5,i], V[6,i]) V'[7,i] = AESRound(V[6,i], V[7,i]) V[0,i] = V'[0,i] V[1,i] = V'[1,i] V[2,i] = V'[2,i] V[3,i] = V'[3,i] V[4,i] = V'[4,i] V[5,i] = V'[5,i] V[6,i] = V'[6,i] V[7,i] = V'[7,i]
The Init Function Init(key, nonce) The Init function initializes a vector of D AEGIS-128L states with the same key and nonce but a different context ctx[i]. Before every initialization update, ctx[i] is XORed into V[3,i] and V[7,i]. Steps: for i in 0..D: V[0,i] = key ^ nonce V[1,i] = C1 V[2,i] = C0 V[3,i] = C1 V[4,i] = key ^ nonce V[5,i] = key ^ C0 V[6,i] = key ^ C1 V[7,i] = key ^ C0 nonce_v = {} key_v = {} for i in 0..D: nonce_v = nonce_v || nonce key_v = key_v || key for i in 0..D: ctx[i] = ZeroPad(Byte(i) || Byte(D - 1), 128) Repeat(10, for i in 0..D: V[3,i] = V[3,i] ^ ctx[i] V[7,i] = V[7,i] ^ ctx[i] Update(nonce_v, key_v) )
The Absorb Function Absorb(ai) The Absorb function is similar to the AEGIS-128L Absorb function but absorbs R bits instead of 256 bits. Steps: t0, t1 = Split(ai, R) Update(t0, t1)
The Enc Function Enc(xi) The Enc function is similar to the AEGIS-128L Enc function but encrypts R bits instead of 256 bits. Steps: z0 = {} z1 = {} for i in 0..D: z0 = z0 || (V[1,i] ^ V[6,i] ^ (V[2,i] & V[3,i])) z1 = z1 || (V[2,i] ^ V[5,i] ^ (V[6,i] & V[7,i])) t0, t1 = Split(xi, R) out0 = t0 ^ z0 out1 = t1 ^ z1 Update(t0, t1) ci = out0 || out1 return ci
The Dec Function Dec(ci) The Dec function is similar to the AEGIS-128L Dec function but decrypts R bits instead of 256 bits. Steps: z0 = {} z1 = {} for i in 0..D: z0 = z0 || (V[1,i] ^ V[6,i] ^ (V[2,i] & V[3,i])) z1 = z1 || (V[2,i] ^ V[5,i] ^ (V[6,i] & V[7,i])) t0, t1 = Split(ci, R) out0 = t0 ^ z0 out1 = t1 ^ z1 Update(out0, out1) xi = out0 || out1 return xi
The DecPartial Function DecPartial(cn) The DecPartial function is similar to the AEGIS-128L DecPartial function but decrypts a non-empty final ciphertext block shorter than R bits. Steps: z0 = {} z1 = {} for i in 0..D: z0 = z0 || (V[1,i] ^ V[6,i] ^ (V[2,i] & V[3,i])) z1 = z1 || (V[2,i] ^ V[5,i] ^ (V[6,i] & V[7,i])) t0, t1 = Split(ZeroPad(cn, R), 128 * D) out0 = t0 ^ z0 out1 = t1 ^ z1 xn = Truncate(out0 || out1, |cn|) v0, v1 = Split(ZeroPad(xn, R), 128 * D) Update(v0, v1) return xn
The Finalize Function Finalize(ad_len_bits, msg_len_bits) The Finalize function finalizes every AEGIS-128L instance and combines the resulting authentication tags using the bitwise exclusive OR operation. Steps: t = {} u = LE64(ad_len_bits) || LE64(msg_len_bits) for i in 0..D: t = t || (V[2,i] ^ u) Repeat(7, Update(t, t)) if tag_len_bits == 128: tag = Zeros(128) for i in 0..D: ti = V[0,i] ^ V[1,i] ^ V[2,i] ^ V[3,i] ^ V[4,i] ^ V[5,i] ^ V[6,i] tag = tag ^ ti else: # 256 bits ti0 = Zeros(128) ti1 = Zeros(128) for i in 0..D: ti0 = ti0 ^ V[0,i] ^ V[1,i] ^ V[2,i] ^ V[3,i] ti1 = ti1 ^ V[4,i] ^ V[5,i] ^ V[6,i] ^ V[7,i] tag = ti0 || ti1 return tag
AEGIS-256X
The Update Function Update(M) The AEGIS-256X Update function is similar to the AEGIS-256 Update function but absorbs R (= 128 * D) bits at once. M is 128 * D bits instead of 128 bits and is split into 128-bit blocks, each of which updates a different AEGIS-256 state. Steps: m = Split(M, 128) for i in 0..D: V'[0,i] = AESRound(V[5,i], V[0,i] ^ m[i]) V'[1,i] = AESRound(V[0,i], V[1,i]) V'[2,i] = AESRound(V[1,i], V[2,i]) V'[3,i] = AESRound(V[2,i], V[3,i]) V'[4,i] = AESRound(V[3,i], V[4,i]) V'[5,i] = AESRound(V[4,i], V[5,i]) V[0,i] = V'[0,i] V[1,i] = V'[1,i] V[2,i] = V'[2,i] V[3,i] = V'[3,i] V[4,i] = V'[4,i] V[5,i] = V'[5,i]
The Init Function Init(key, nonce) The Init function initializes a vector of D AEGIS-256 states with the same key and nonce but a different context ctx[i]. Before every initialization update, ctx[i] is XORed into V[3,i] and V[5,i]. Steps: k0, k1 = Split(key, 128) n0, n1 = Split(nonce, 128) for i in 0..D: V[0,i] = k0 ^ n0 V[1,i] = k1 ^ n1 V[2,i] = C1 V[3,i] = C0 V[4,i] = k0 ^ C0 V[5,i] = k1 ^ C1 k0_v, k1_v = {}, {} k0n0_v, k1n1_v = {}, {} for i in 0..D: k0_v = k0_v || k0 k1_v = k1_v || k1 k0n0_v = k0n0_v || (k0 ^ n0) k1n1_v = k1n1_v || (k1 ^ n1) for i in 0..D: ctx[i] = ZeroPad(Byte(i) || Byte(D - 1), 128) Repeat(4, for i in 0..D: V[3,i] = V[3,i] ^ ctx[i] V[5,i] = V[5,i] ^ ctx[i] Update(k0_v) for i in 0..D: V[3,i] = V[3,i] ^ ctx[i] V[5,i] = V[5,i] ^ ctx[i] Update(k1_v) for i in 0..D: V[3,i] = V[3,i] ^ ctx[i] V[5,i] = V[5,i] ^ ctx[i] Update(k0n0_v) for i in 0..D: V[3,i] = V[3,i] ^ ctx[i] V[5,i] = V[5,i] ^ ctx[i] Update(k1n1_v) )
The Absorb Function Absorb(ai) The Absorb function is similar to the AEGIS-256 Absorb function but absorbs R bits instead of 128 bits. Steps: Update(ai)
The Enc Function Enc(xi) The Enc function is similar to the AEGIS-256 Enc function but encrypts R bits instead of 128 bits. Steps: z = {} for i in 0..D: z = z || (V[1,i] ^ V[4,i] ^ V[5,i] ^ (V[2,i] & V[3,i])) Update(xi) ci = xi ^ z return ci
The Dec Function Dec(ci) The Dec function is similar to the AEGIS-256 Dec function but decrypts R bits instead of 128 bits. Steps: z = {} for i in 0..D: z = z || (V[1,i] ^ V[4,i] ^ V[5,i] ^ (V[2,i] & V[3,i])) xi = ci ^ z Update(xi) return xi
The DecPartial Function DecPartial(cn) The DecPartial function is similar to the AEGIS-256 DecPartial function but decrypts a non-empty final ciphertext block shorter than R bits. Steps: z = {} for i in 0..D: z = z || (V[1,i] ^ V[4,i] ^ V[5,i] ^ (V[2,i] & V[3,i])) t = ZeroPad(cn, R) out = t ^ z xn = Truncate(out, |cn|) v = ZeroPad(xn, 128 * D) Update(v) return xn
The Finalize Function Finalize(ad_len_bits, msg_len_bits) The Finalize function finalizes every AEGIS-256 instance and combines the resulting authentication tags using the bitwise exclusive OR operation. Steps: t = {} u = LE64(ad_len_bits) || LE64(msg_len_bits) for i in 0..D: t = t || (V[3,i] ^ u) Repeat(7, Update(t)) if tag_len_bits == 128: tag = Zeros(128) for i in 0..D: ti = V[0,i] ^ V[1,i] ^ V[2,i] ^ V[3,i] ^ V[4,i] ^ V[5,i] tag = tag ^ ti else: # 256 bits ti0 = Zeros(128) ti1 = Zeros(128) for i in 0..D: ti0 = ti0 ^ V[0,i] ^ V[1,i] ^ V[2,i] ti1 = ti1 ^ V[3,i] ^ V[4,i] ^ V[5,i] tag = ti0 || ti1 return tag
Implementation Considerations AEGIS-128X and AEGIS-256X with a degree of 1 are identical to AEGIS-128L and AEGIS-256, respectively. This property can be used to reduce the size of a generic implementation. In AEGIS-128X, V can be represented as eight 256-bit registers (when D = 2) or eight 512-bit registers (when D = 4). In AEGIS-256X, V can be represented as six 256-bit registers (when D = 2) or six 512-bit registers (when D = 4). With this representation, loops over 0..D in the above pseudocode can be replaced by vector instructions.
Operational Considerations The AEGIS parallel modes are specialized and can only improve performance on specific CPUs. The degrees of parallelism that implementations are encouraged to support are 2 (for CPUs with 256-bit registers) and 4 (for CPUs with 512-bit registers). The resulting algorithms are called AEGIS-128X2, AEGIS-128X4, AEGIS-256X2, and AEGIS-256X4. The following table summarizes how many bits are processed in parallel (rate), the memory requirements (state size), and the minimum vector register size a CPU should support for optimal performance. AEGIS Parallel Mode Parameters
Algorithm Rate (Bits) Optimal Register Size State Size (Bits)
AEGIS-128L 256 128 bits 1024
AEGIS-128X2 512 256 bits 2048
AEGIS-128X4 1024 512 bits 4096
AEGIS-256 128 128 bits 768
AEGIS-256X2 256 256 bits 1536
AEGIS-256X4 512 512 bits 3072
Note that architectures with smaller vector registers, but with many registers and large pipelines, may still benefit from the parallel modes. Protocols SHOULD opt for a parallel mode only when all the involved parties agree on a specific variant. AEGIS-128L and AEGIS-256 SHOULD remain the default choices. Implementations MAY choose not to include the parallel AEGIS modes.
Encoding (ct, tag) Tuples Applications MAY keep the ciphertext and the authentication tag in distinct structures or encode both as a single string. In the latter case, the tag MUST immediately follow the ciphertext: combined_ct = ct || tag The length of combined_ct MUST be less than or equal to C_MAX.
AEGIS as a Stream Cipher All AEGIS variants can also be used as stream ciphers. Stream(len, key, nonce) The Stream function expands a key and an optional nonce into a variable-length keystream. Inputs:
  • len: the length of the keystream to generate in bits.
  • key: the AEGIS key.
  • nonce: the AEGIS nonce. If unspecified, it is set to N_MAX zero bytes.
Outputs:
  • stream: the keystream.
Steps: if len == 0: return {} else: stream, tag = Encrypt(Zeros(len), {}, key, nonce) return stream This is equivalent to encrypting a len all-zero bits message without associated data and discarding the authentication tag. Instead of relying on the generic Encrypt function, implementations can omit the Finalize function. After initialization, the Update function is called with constant parameters, allowing further optimizations.
AEGIS as a Message Authentication Code All AEGIS variants can be used to construct a message authentication code (MAC). For all variants, the Mac function takes a key, a nonce, and data as input and produces a 128- or 256-bit tag as output. Mac(data, key, nonce) Security:
  • This is the only function that allows the reuse of (key, nonce) pairs with different inputs.
  • AEGIS-based MAC functions MUST NOT be used as hash functions. If the key is known, inputs causing state collisions can easily be crafted.
  • Unlike hash-based MACs, tags MUST NOT be used for key derivation because there is no guarantee that they are uniformly random.
Inputs:
  • data: the input data to authenticate (length MUST be less than or equal to A_MAX).
  • key: the secret key.
  • nonce: the public nonce.
Outputs:
  • tag: the authentication tag.
AEGISMAC-128L AEGISMAC-128L refers to the Mac function based on the building blocks of AEGIS-128L. Steps: Init(key, nonce) data_blocks = Split(ZeroPad(data, 256), 256) for di in data_blocks: Absorb(di) tag = Finalize(|data|, tag_len_bits) return tag
AEGISMAC-256 AEGISMAC-256 refers to the Mac function based on the building blocks of AEGIS-256. Steps: Init(key, nonce) data_blocks = Split(ZeroPad(data, 128), 128) for di in data_blocks: Absorb(di) tag = Finalize(|data|, tag_len_bits) return tag
AEGISMAC-128X AEGISMAC-128X is based on the building blocks of AEGIS-128X but replaces the Finalize function with a dedicated FinalizeMac function.
The Mac Function Steps: Init(key, nonce) data_blocks = Split(ZeroPad(data, R), R) for di in data_blocks: Absorb(di) tag = FinalizeMac(|data|) return tag
The FinalizeMac Function FinalizeMac(data_len_bits) The FinalizeMac function computes a 128- or 256-bit tag that authenticates the input data. It finalizes all the instances, absorbs the resulting tags into the first state, and computes the final tag using that single state, as done in AEGIS-128L. Steps: t = {} u = LE64(data_len_bits) || LE64(tag_len_bits) for i in 0..D: t = t || (V[2,i] ^ u) Repeat(7, Update(t, t)) tags = {} if tag_len_bits == 128: for i in 0..D: # tag from state 0 is included ti = V[0,i] ^ V[1,i] ^ V[2,i] ^ V[3,i] ^ V[4,i] ^ V[5,i] ^ V[6,i] tags = tags || ti else: # 256 bits for i in 1..D: # tag from state 0 is skipped ti0 = V[0,i] ^ V[1,i] ^ V[2,i] ^ V[3,i] ti1 = V[4,i] ^ V[5,i] ^ V[6,i] ^ V[7,i] tags = tags || (ti0 || ti1) if D > 1: # Absorb tags into state 0; other states are not used anymore for v in Split(tags, 256): x0, x1 = Split(v, 128) Absorb(ZeroPad(x0, R / 2) || ZeroPad(x1, R / 2)) u = LE64(D) || LE64(tag_len_bits) t = ZeroPad(V[2,0] ^ u, R) Repeat(7, Update(t, t)) if tag_len_bits == 128: tag = V[0,0] ^ V[1,0] ^ V[2,0] ^ V[3,0] ^ V[4,0] ^ V[5,0] ^ V[6,0] else: # 256 bits t0 = V[0,0] ^ V[1,0] ^ V[2,0] ^ V[3,0] t1 = V[4,0] ^ V[5,0] ^ V[6,0] ^ V[7,0] tag = t0 || t1 return tag
AEGISMAC-256X AEGISMAC-256X is based on the building blocks of AEGIS-256X but replaces the Finalize function with a dedicated FinalizeMac function.
The Mac Function Steps: Init(key, nonce) data_blocks = Split(ZeroPad(data, R), R) for di in data_blocks: Absorb(di) tag = FinalizeMac(|data|) return tag
The FinalizeMac Function FinalizeMac(data_len_bits) The FinalizeMac function computes a 128- or 256-bit tag that authenticates the input data. It finalizes all the instances, absorbs the resulting tags into the first state, and computes the final tag using that single state, as done in AEGIS-256. t = {} u = LE64(data_len_bits) || LE64(tag_len_bits) for i in 0..D: t = t || (V[3,i] ^ u) Repeat(7, Update(t)) tags = {} if tag_len_bits == 128: for i in 1..D: # tag from state 0 is skipped ti = V[0,i] ^ V[1,i] ^ V[2,i] ^ V[3,i] ^ V[4,i] ^ V[5,i] tags = tags || ti else: # 256 bits for i in 1..D: # tag from state 0 is skipped ti0 = V[0,i] ^ V[1,i] ^ V[2,i] ti1 = V[3,i] ^ V[4,i] ^ V[5,i] tags = tags || (ti0 || ti1) if D > 1: # Absorb tags into state 0; other states are not used anymore for v in Split(tags, 128): Absorb(ZeroPad(v, R)) u = LE64(D) || LE64(tag_len_bits) t = ZeroPad(V[3,0] ^ u, R) Repeat(7, Update(t)) if tag_len_bits == 128: tag = V[0,0] ^ V[1,0] ^ V[2,0] ^ V[3,0] ^ V[4,0] ^ V[5,0] else: # 256 bits t0 = V[0,0] ^ V[1,0] ^ V[2,0] t1 = V[3,0] ^ V[4,0] ^ V[5,0] tag = t0 || t1 return tag
Security Considerations
Usage Guidelines
Key and Nonce Selection When AEGIS is used for encryption, a nonce MUST only be used once for a given key, even with different tag lengths. Failure to do so would immediately reveal the bitwise difference between two messages. Every key MUST be randomly chosen from a uniform distribution. The nonce MAY be public or predictable. It can be a counter, the output of a permutation, or a generator with a long period. With AEGIS-128L and AEGIS-128X, random nonces can safely encrypt up to 248 messages using the same key with negligible (~2-33) collision probability. This is consistent with Section 8 of . With AEGIS-256 and AEGIS-256X, random nonces can be used with no practical limits.
Committing Security An authentication tag may verify under multiple keys, nonces, or associated data, but AEGIS is assumed to be key committing in the receiver-binding game. This mitigates common attacks when used with low-entropy keys such as passwords. Finding distinct keys and/or nonces that successfully verify the same (ad, ct, tag) tuple is expected to require ~264 attempts with a 128-bit authentication tag and ~2128 attempts with a 256-bit tag. AEGIS is fully committing in the restricted setting where an adversary cannot control the associated data. As shown in , with the ability to alter the associated data, it is possible to efficiently find multiple keys that will verify the same authenticated ciphertext. Protocols mandating a fully committing scheme without that restriction can provide the associated data as input to a cryptographic hash function and use the output as the ad parameter of the Encrypt and Decrypt functions. The selected hash function must ensure a minimum of 128-bit collision and preimage resistance. An instance of such a function is SHA-256 . Alternatively, the associated data can be fed into a collision-resistant key derivation function (KDF), such as the HMAC-based key derivation function (HKDF) , via the info input to derive the key parameter. The ad parameter can then be left empty. Note that the salt input MUST NOT be used since large salts get hashed, which affects commitment. Furthermore, this requires values concatenated to form the info input to be unambiguously encoded, like by appending their lengths.
Multi-User Security AEGIS nonces match the size of the key. AEGIS-128L and AEGIS-128X feature 128-bit nonces, offering an extra 32 bits compared to the commonly used AEADs in IETF protocols at the time of writing. The AEGIS-256 and AEGIS-256X variants provide even larger nonces. With 192 random bits, 64 bits remain available to optionally encode additional information. In all these variants, unused nonce bits can encode a key identifier, enhancing multi-user security. If every key has a unique identifier, multi-target attacks do not provide any advantage over single-target attacks.
Implementation Security If tag verification fails, the unverified plaintext and computed authentication tag MUST NOT be released. As shown in , even a partial leak of the plaintext without verification facilitates chosen ciphertext attacks. The security of AEGIS against timing and physical attacks is limited by the implementation of the underlying AESRound function. Failure to implement AESRound in a fashion safe against timing and physical attacks, such as differential power analysis, timing analysis, or fault injection attacks, may lead to leakage of secret key material or state information. The exact mitigations required for timing and physical attacks depend on the threat model in question. Regardless of the variant, the key and nonce are only required by the Init function; other functions only depend on the resulting state. Therefore, implementations can overwrite ephemeral keys with zeros right after the last Update call of the initialization function.
Security Guarantees AEGIS-256 offers 256-bit security against plaintext and state recovery, whereas AEGIS-128L offers 128-bit security. Under the assumption that the secret key is unknown to the attacker, all AEGIS variants offer at least 128-bit security against forgery attacks. Encrypting the same message with the same key and nonce but different associated data generates distinct ciphertexts that do not reveal any additional information about the message. However, (key, nonce) pairs MUST NOT be reused, even if the associated data differs. AEGIS has been shown to have reforgeability resilience in . Without the ability to set the associated data, a successful forgery does not increase the probability of subsequent forgeries. AEGIS-128X and AEGIS-256X share the same security properties and requirements as AEGIS-128L and AEGIS-256, respectively. In particular, the security level and usage limits remain the same . AEGIS is considered secure against guess-and-determine attacks aimed at recovering the state from observed ciphertexts. This resilience extends to quantum adversaries operating within the Q1 model, where the attacker has access to a quantum computer but is restricted to classical (non-quantum) communications with the systems under attack. In this model, quantum attacks offer no practical advantage in decrypting previously recorded ciphertexts or in recovering the encryption key. This document extends the AEGIS specification by introducing optional support for 256-bit authentication tags, which are constructed similarly to the 128-bit tags. As shown in , with 256-bit tags, all AEGIS variants achieve more than 128-bit security against forgery by differential attacks. Security analyses of AEGIS can be found in , , , , , , , , , , and .
IANA Considerations IANA has assigned the following identifiers in the "AEAD Algorithms" registry and added this document as the reference for each: AEGIS Entries in the AEAD Algorithms Registry
Numeric ID Name
32 AEAD_AEGIS128L
33 AEAD_AEGIS256
34 AEAD_AEGIS128X2
35 AEAD_AEGIS128X4
36 AEAD_AEGIS256X2
37 AEAD_AEGIS256X4
References Normative References Advanced Encryption Standard (AES) NIST Key words for use in RFCs to Indicate Requirement Levels In many standards track documents several words are used to signify the requirements in the specification. These words are often capitalized. This document defines these words as they should be interpreted in IETF documents. This document specifies an Internet Best Current Practices for the Internet Community, and requests discussion and suggestions for improvements. An Interface and Algorithms for Authenticated Encryption This document defines algorithms for Authenticated Encryption with Associated Data (AEAD), and defines a uniform interface and a registry for such algorithms. The interface and registry can be used as an application-independent set of cryptoalgorithm suites. This approach provides advantages in efficiency and security, and promotes the reuse of crypto implementations. [STANDARDS-TRACK] HMAC-based Extract-and-Expand Key Derivation Function (HKDF) This document specifies a simple Hashed Message Authentication Code (HMAC)-based key derivation function (HKDF), which can be used as a building block in various protocols and applications. The key derivation function (KDF) is intended to support a wide range of applications and requirements, and is conservative in its use of cryptographic hash functions. This document is not an Internet Standards Track specification; it is published for informational purposes. US Secure Hash Algorithms (SHA and SHA-based HMAC and HKDF) Federal Information Processing Standard, FIPS Ambiguity of Uppercase vs Lowercase in RFC 2119 Key Words RFC 2119 specifies common key words that may be used in protocol specifications. This document aims to reduce the ambiguity by clarifying that only UPPERCASE usage of the key words have the defined special meanings. Informative References AEGIS: A Fast Authenticated Encryption Algorithm (v1.1) Nanyang Technological University KU Leuven Differential fault attack on AES-based encryption schemes: application to B5G/6G ciphers-Rocca, Rocca-S and AEGIS Indraprastha Institute of Information Technology Delhi; University of Hyogo University of Hyogo Indian Statistical Institute Kolkata University of Hyogo University of Hyogo; Indian Institute of Technology Bhilai Journal of Cryptographic Engineering, vol. 14, pp. 595-607 Single-query Quantum Hidden Shift Attacks Université de Lorraine, CNRS, Inria, LORIA Université de Rennes, CNRS, Inria, IRISA Cryptology ePrint Archive, Paper 2023/1306 Adding more parallelism to the AEGIS authenticated encryption algorithms Fastly Inc. Cryptology ePrint Archive, Paper 2023/523 Analyzing the Linear Keystream Biases in AEGIS Graz University of Technology Graz University of Technology Graz University of Technology IACR Transactions on Symmetric Cryptology, vol. 2019, no. 4, pp. 348-368 Reforgeability of Authenticated Encryption Schemes Beuth Hochschule für Technik Berlin Bauhaus-Universität Weimar Bauhaus-Universität Weimar Bauhaus-Universität Weimar Cryptology ePrint Archive, Paper 2017/332 Key Committing Security Analysis of AEGIS University of Hyogo University of Hyogo Cryptology ePrint Archive, Paper 2023/1495 Guess-and-Determine Attacks on AEGIS State Key Laboratory of Cryptology State Key Laboratory of Information Security, Institute of Information Engineering, Chinese Academy of Sciences; School of Cyber Security, University of Chinese Academy of Sciences State Key Laboratory of Cryptology The Computer Journal, vol. 65, no. 8, pp. 2221-2230 Partitioning Oracle Attacks Cornell Tech Cornell Tech Cornell Tech 30th USENIX Security Symposium (USENIX Security 21), pp. 195-212 Weak Keys in Reduced AEGIS and Tiaoxin East China Normal University; University of Hyogo University of Hyogo; National Institute of Information and Communications Technology; PRESTO, Japan Science and Technology Agency University of Applied Sciences and Arts Northwestern Switzerland University of Hyogo IACR Transactions on Symmetric Cryptology, vol. 2021, no. 2, pp. 104-139 Linear Biases in AEGIS Keystream ANSSI Selected Areas in Cryptography (SAC 2014), Lecture Notes in Computer Science, vol. 8781, pp. 290-305 Recommendation for Block Cipher Modes of Operation: Galois/Counter Mode (GCM) and GMAC NIST Bit-Wise Analysis for Forgery Attacks on AES-Based AEAD Schemes University of Hyogo Mitsubishi Electric Corporation University of Hyogo Advances in Information and Computer Security (IWSEC 2024), Lecture Notes in Computer Science, vol. 14977, pp. 3-22 MILP-based security evaluation for AEGIS/Tiaoxin-346/Rocca University of Hyogo University of Hyogo University of Hyogo University of Hyogo; National Institute of Information and Communications Technology IET Information Security, vol 17, no. 3, pp. 458-467 AEGIS Test Vectors commit 8e289c4 Can Caesar Beat Galois? EPFL EPFL Applied Cryptography and Network Security (ACNS 2018), Lecture Notes in Computer Science, vol. 10892, pp. 476-494
Test Vectors The following test vectors are also available in JSON format at . In this format, byte strings are represented as JSON strings containing their hexadecimal encoding.
AESRound Test Vector in : 000102030405060708090a0b0c0d0e0f rk : 101112131415161718191a1b1c1d1e1f out : 7a7b4e5638782546a8c0477a3b813f43
AEGIS-128L Test Vectors
Update Test Vector S0 : 9b7e60b24cc873ea894ecc07911049a3 S1 : 330be08f35300faa2ebf9a7b0d274658 S2 : 7bbd5bd2b049f7b9b515cf26fbe7756c S3 : c35a00f55ea86c3886ec5e928f87db18 S4 : 9ebccafce87cab446396c4334592c91f S5 : 58d83e31f256371e60fc6bb257114601 S6 : 1639b56ea322c88568a176585bc915de S7 : 640818ffb57dc0fbc2e72ae93457e39a M0 : 033e6975b94816879e42917650955aa0 M1 : fcc1968a46b7e97861bd6e89af6aa55f After Update: S0 : 596ab773e4433ca0127c73f60536769d S1 : 790394041a3d26ab697bde865014652d S2 : 38cf49e4b65248acd533041b64dd0611 S3 : 16d8e58748f437bfff1797f780337cee S4 : 9689ecdf08228c74d7e3360cca53d0a5 S5 : a21746bb193a569e331e1aa985d0d729 S6 : 09d714e6fcf9177a8ed1cde7e3d259a6 S7 : 61279ba73167f0ab76f0a11bf203bdff
Test Vector 1 key : 10010000000000000000000000000000 nonce : 10000200000000000000000000000000 ad : msg : 00000000000000000000000000000000 ct : c1c0e58bd913006feba00f4b3cc3594e tag128: abe0ece80c24868a226a35d16bdae37a tag256: 25835bfbb21632176cf03840687cb968 cace4617af1bd0f7d064c639a5c79ee4
Test Vector 2 key : 10010000000000000000000000000000 nonce : 10000200000000000000000000000000 ad : msg : ct : tag128: c2b879a67def9d74e6c14f708bbcc9b4 tag256: 1360dc9db8ae42455f6e5b6a9d488ea4 f2184c4e12120249335c4ee84bafe25d
Test Vector 3 key : 10010000000000000000000000000000 nonce : 10000200000000000000000000000000 ad : 0001020304050607 msg : 000102030405060708090a0b0c0d0e0f 101112131415161718191a1b1c1d1e1f ct : 79d94593d8c2119d7e8fd9b8fc77845c 5c077a05b2528b6ac54b563aed8efe84 tag128: cc6f3372f6aa1bb82388d695c3962d9a tag256: 022cb796fe7e0ae1197525ff67e30948 4cfbab6528ddef89f17d74ef8ecd82b3
Test Vector 4 key : 10010000000000000000000000000000 nonce : 10000200000000000000000000000000 ad : 0001020304050607 msg : 000102030405060708090a0b0c0d ct : 79d94593d8c2119d7e8fd9b8fc77 tag128: 5c04b3dba849b2701effbe32c7f0fab7 tag256: 86f1b80bfb463aba711d15405d094baf 4a55a15dbfec81a76f35ed0b9c8b04ac
Test Vector 5 key : 10010000000000000000000000000000 nonce : 10000200000000000000000000000000 ad : 000102030405060708090a0b0c0d0e0f 101112131415161718191a1b1c1d1e1f 20212223242526272829 msg : 101112131415161718191a1b1c1d1e1f 202122232425262728292a2b2c2d2e2f 3031323334353637 ct : b31052ad1cca4e291abcf2df3502e6bd b1bfd6db36798be3607b1f94d34478aa 7ede7f7a990fec10 tag128: 7542a745733014f9474417b337399507 tag256: b91e2947a33da8bee89b6794e647baf0 fc835ff574aca3fc27c33be0db2aff98
Test Vector 6 This test MUST return a "verification failed" error. key : 10000200000000000000000000000000 nonce : 10010000000000000000000000000000 ad : 0001020304050607 ct : 79d94593d8c2119d7e8fd9b8fc77 tag128: 5c04b3dba849b2701effbe32c7f0fab7 tag256: 86f1b80bfb463aba711d15405d094baf 4a55a15dbfec81a76f35ed0b9c8b04ac
Test Vector 7 This test MUST return a "verification failed" error. key : 10010000000000000000000000000000 nonce : 10000200000000000000000000000000 ad : 0001020304050607 ct : 79d94593d8c2119d7e8fd9b8fc78 tag128: 5c04b3dba849b2701effbe32c7f0fab7 tag256: 86f1b80bfb463aba711d15405d094baf 4a55a15dbfec81a76f35ed0b9c8b04ac
Test Vector 8 This test MUST return a "verification failed" error. key : 10010000000000000000000000000000 nonce : 10000200000000000000000000000000 ad : 0001020304050608 ct : 79d94593d8c2119d7e8fd9b8fc77 tag128: 5c04b3dba849b2701effbe32c7f0fab7 tag256: 86f1b80bfb463aba711d15405d094baf 4a55a15dbfec81a76f35ed0b9c8b04ac
Test Vector 9 This test MUST return a "verification failed" error. key : 10010000000000000000000000000000 nonce : 10000200000000000000000000000000 ad : 0001020304050607 ct : 79d94593d8c2119d7e8fd9b8fc77 tag128: 6c04b3dba849b2701effbe32c7f0fab8 tag256: 86f1b80bfb463aba711d15405d094baf 4a55a15dbfec81a76f35ed0b9c8b04ad
AEGIS-256 Test Vectors
Update Test Vector S0 : 1fa1207ed76c86f2c4bb40e8b395b43e S1 : b44c375e6c1e1978db64bcd12e9e332f S2 : 0dab84bfa9f0226432ff630f233d4e5b S3 : d7ef65c9b93e8ee60c75161407b066e7 S4 : a760bb3da073fbd92bdc24734b1f56fb S5 : a828a18d6a964497ac6e7e53c5f55c73 M : b165617ed04ab738afb2612c6d18a1ec After Update: S0 : e6bc643bae82dfa3d991b1b323839dcd S1 : 648578232ba0f2f0a3677f617dc052c3 S2 : ea788e0e572044a46059212dd007a789 S3 : 2f1498ae19b80da13fba698f088a8590 S4 : a54c2ee95e8c2a2c3dae2ec743ae6b86 S5 : a3240fceb68e32d5d114df1b5363ab67
Test Vector 1 key : 10010000000000000000000000000000 00000000000000000000000000000000 nonce : 10000200000000000000000000000000 00000000000000000000000000000000 ad : msg : 00000000000000000000000000000000 ct : 754fc3d8c973246dcc6d741412a4b236 tag128: 3fe91994768b332ed7f570a19ec5896e tag256: 1181a1d18091082bf0266f66297d167d 2e68b845f61a3b0527d31fc7b7b89f13
Test Vector 2 key : 10010000000000000000000000000000 00000000000000000000000000000000 nonce : 10000200000000000000000000000000 00000000000000000000000000000000 ad : msg : ct : tag128: e3def978a0f054afd1e761d7553afba3 tag256: 6a348c930adbd654896e1666aad67de9 89ea75ebaa2b82fb588977b1ffec864a
Test Vector 3 key : 10010000000000000000000000000000 00000000000000000000000000000000 nonce : 10000200000000000000000000000000 00000000000000000000000000000000 ad : 0001020304050607 msg : 000102030405060708090a0b0c0d0e0f 101112131415161718191a1b1c1d1e1f ct : f373079ed84b2709faee373584585d60 accd191db310ef5d8b11833df9dec711 tag128: 8d86f91ee606e9ff26a01b64ccbdd91d tag256: b7d28d0c3c0ebd409fd22b4416050307 3a547412da0854bfb9723020dab8da1a
Test Vector 4 key : 10010000000000000000000000000000 00000000000000000000000000000000 nonce : 10000200000000000000000000000000 00000000000000000000000000000000 ad : 0001020304050607 msg : 000102030405060708090a0b0c0d ct : f373079ed84b2709faee37358458 tag128: c60b9c2d33ceb058f96e6dd03c215652 tag256: 8c1cc703c81281bee3f6d9966e14948b 4a175b2efbdc31e61a98b4465235c2d9
Test Vector 5 key : 10010000000000000000000000000000 00000000000000000000000000000000 nonce : 10000200000000000000000000000000 00000000000000000000000000000000 ad : 000102030405060708090a0b0c0d0e0f 101112131415161718191a1b1c1d1e1f 20212223242526272829 msg : 101112131415161718191a1b1c1d1e1f 202122232425262728292a2b2c2d2e2f 3031323334353637 ct : 57754a7d09963e7c787583a2e7b859bb 24fa1e04d49fd550b2511a358e3bca25 2a9b1b8b30cc4a67 tag128: ab8a7d53fd0e98d727accca94925e128 tag256: a3aca270c006094d71c20e6910b5161c 0826df233d08919a566ec2c05990f734
Test Vector 6 This test MUST return a "verification failed" error. key : 10000200000000000000000000000000 00000000000000000000000000000000 nonce : 10010000000000000000000000000000 00000000000000000000000000000000 ad : 0001020304050607 ct : f373079ed84b2709faee37358458 tag128: c60b9c2d33ceb058f96e6dd03c215652 tag256: 8c1cc703c81281bee3f6d9966e14948b 4a175b2efbdc31e61a98b4465235c2d9
Test Vector 7 This test MUST return a "verification failed" error. key : 10010000000000000000000000000000 00000000000000000000000000000000 nonce : 10000200000000000000000000000000 00000000000000000000000000000000 ad : 0001020304050607 ct : f373079ed84b2709faee37358459 tag128: c60b9c2d33ceb058f96e6dd03c215652 tag256: 8c1cc703c81281bee3f6d9966e14948b 4a175b2efbdc31e61a98b4465235c2d9
Test Vector 8 This test MUST return a "verification failed" error. key : 10010000000000000000000000000000 00000000000000000000000000000000 nonce : 10000200000000000000000000000000 00000000000000000000000000000000 ad : 0001020304050608 ct : f373079ed84b2709faee37358458 tag128: c60b9c2d33ceb058f96e6dd03c215652 tag256: 8c1cc703c81281bee3f6d9966e14948b 4a175b2efbdc31e61a98b4465235c2d9
Test Vector 9 This test MUST return a "verification failed" error. key : 10010000000000000000000000000000 00000000000000000000000000000000 nonce : 10000200000000000000000000000000 00000000000000000000000000000000 ad : 0001020304050607 ct : f373079ed84b2709faee37358458 tag128: c60b9c2d33ceb058f96e6dd03c215653 tag256: 8c1cc703c81281bee3f6d9966e14948b 4a175b2efbdc31e61a98b4465235c2da
AEGIS-128X2 Test Vectors
Initial State key : 000102030405060708090a0b0c0d0e0f nonce : 101112131415161718191a1b1c1d1e1f ctx[0]: 00010000000000000000000000000000 ctx[1]: 01010000000000000000000000000000 After initialization: V[0,0]: a4fc1ad9a72942fb88bd2cabbba6509a V[0,1]: 80a40e392fc71084209b6c3319bdc6cc V[1,0]: 380f435cf801763b1f0c2a2f7212052d V[1,1]: 73796607b59b1b650ee91c152af1f18a V[2,0]: 6ee1de433ea877fa33bc0782abff2dcb V[2,1]: b9fab2ab496e16d1facaffd5453cbf14 V[3,0]: 85f94b0d4263bfa86fdf45a603d8b6ac V[3,1]: 90356c8cadbaa2c969001da02e3feca0 V[4,0]: 09bd69ad3730174bcd2ce9a27cd1357e V[4,1]: e610b45125796a4fcf1708cef5c4f718 V[5,0]: fcdeb0cf0a87bf442fc82383ddb0f6d6 V[5,1]: 61ad32a4694d6f3cca313a2d3f4687aa V[6,0]: 571c207988659e2cdfbdaae77f4f37e3 V[6,1]: 32e6094e217573bf91fb28c145a3efa8 V[7,0]: ca549badf8faa58222412478598651cf V[7,1]: 3407279a54ce76d2e2e8a90ec5d108eb
Test Vector 1 key : 000102030405060708090a0b0c0d0e0f nonce : 101112131415161718191a1b1c1d1e1f ad : msg : ct : tag128: 63117dc57756e402819a82e13eca8379 tag256: b92c71fdbd358b8a4de70b27631ace90 cffd9b9cfba82028412bac41b4f53759
Test Vector 2 key : 000102030405060708090a0b0c0d0e0f nonce : 101112131415161718191a1b1c1d1e1f ad : 0102030401020304 msg : 04050607040506070405060704050607 04050607040506070405060704050607 04050607040506070405060704050607 04050607040506070405060704050607 04050607040506070405060704050607 04050607040506070405060704050607 04050607040506070405060704050607 0405060704050607 ct : 5795544301997f93621b278809d6331b 3bfa6f18e90db12c4aa35965b5e98c5f c6fb4e54bcb6111842c20637252eff74 7cb3a8f85b37de80919a589fe0f24872 bc926360696739e05520647e390989e1 eb5fd42f99678a0276a498f8c454761c 9d6aacb647ad56be62b29c22cd4b5761 b38f43d5a5ee062f tag128: 1aebc200804f405cab637f2adebb6d77 tag256: c471876f9b4978c44f2ae1ce770cdb11 a094ee3feca64e7afcd48bfe52c60eca
AEGIS-128X4 Test Vectors
Initial State key : 000102030405060708090a0b0c0d0e0f nonce : 101112131415161718191a1b1c1d1e1f ctx[0]: 00030000000000000000000000000000 ctx[1]: 01030000000000000000000000000000 ctx[2]: 02030000000000000000000000000000 ctx[3]: 03030000000000000000000000000000 After initialization: V[0,0]: 924eb07635003a37e6c6575ba8ce1929 V[0,1]: c8b6a5d91475445e936d48e794be0ce2 V[0,2]: fcd37d050e24084befe3bbb219d64760 V[0,3]: 2e9f58cfb893a8800220242c373a8b18 V[1,0]: 1a1f60c4fab64e5471dc72edfcf6fe6b V[1,1]: c1e525ebea2d6375a9edd045dce96381 V[1,2]: 97a3e25abd228a44d4a14a6d3fe9185c V[1,3]: c2d4cf7f4287a98744645674265d4ca8 V[2,0]: 7bb50c534f6ec4780530ff1cce8a16e8 V[2,1]: 7b08d57557da0b5ef7b5f7d98b0ba189 V[2,2]: 6bfcac34ddb68404821a4d665303cb0f V[2,3]: d95626f6dfad1aed7467622c38529932 V[3,0]: af339fd2d50ee45fc47665c647cf6586 V[3,1]: d0669b39d140f0e118a4a511efe2f95a V[3,2]: 7a94330f35c194fadda2a87e42cdeccc V[3,3]: 233b640d1f4d56e2757e72c1a9d8ecb1 V[4,0]: 9f93737d699ba05c11e94f2b201bef5e V[4,1]: 61caf387cf7cfd3f8300ac7680ccfd76 V[4,2]: 5825a671ecef03b7a9c98a601ae32115 V[4,3]: 87a1fe4d558161a8f4c38731f3223032 V[5,0]: 7a5aca78d636c05bbc702b2980196ab6 V[5,1]: 915d868408495d07eb527789f282c575 V[5,2]: d0947bfbc1d3309cdffc9be1503aea62 V[5,3]: 8834ea57a15b9fbdc0245464a4b8cbef V[6,0]: e46f4cf71a95ac45b6f0823e3aba1a86 V[6,1]: 8c4ecef682fc44a8eba911b3fc7d99f9 V[6,2]: a4fb61e2c928a2ca760b8772f2ea5f2e V[6,3]: 3d34ea89da73caa3016c280500a155a3 V[7,0]: 85075f0080e9d618e7eb40f57c32d9f7 V[7,1]: d2ab2b320c6e93b155a3787cb83e5281 V[7,2]: 0b3af0250ae36831a1b072e499929bcb V[7,3]: 5cce4d00329d69f1aae36aa541347512
Test Vector 1 key : 000102030405060708090a0b0c0d0e0f nonce : 101112131415161718191a1b1c1d1e1f ad : msg : ct : tag128: 5bef762d0947c00455b97bb3af30dfa3 tag256: a4b25437f4be93cfa856a2f27e4416b4 2cac79fd4698f2cdbe6af25673e10a68
Test Vector 2 key : 000102030405060708090a0b0c0d0e0f nonce : 101112131415161718191a1b1c1d1e1f ad : 0102030401020304 msg : 04050607040506070405060704050607 04050607040506070405060704050607 04050607040506070405060704050607 04050607040506070405060704050607 04050607040506070405060704050607 04050607040506070405060704050607 04050607040506070405060704050607 0405060704050607 ct : e836118562f4479c9d35c17356a83311 4c21f9aa39e4dda5e5c87f4152a00fce 9a7c38f832eafe8b1c12f8a7cf12a81a 1ad8a9c24ba9dedfbdaa586ffea67ddc 801ea97d9ab4a872f42d0e352e2713da cd609f9442c17517c5a29daf3e2a3fac 4ff6b1380c4e46df7b086af6ce6bc1ed 594b8dd64aed2a7e tag128: 0e56ab94e2e85db80f9d54010caabfb4 tag256: 69abf0f64a137dd6e122478d777e98bc 422823006cf57f5ee822dd78397230b2
AEGIS-256X2 Test Vectors
Initial State key : 000102030405060708090a0b0c0d0e0f 101112131415161718191a1b1c1d1e1f nonce : 101112131415161718191a1b1c1d1e1f 202122232425262728292a2b2c2d2e2f ctx[0]: 00010000000000000000000000000000 ctx[1]: 01010000000000000000000000000000 After initialization: V[0,0]: eca2bf4538442e8712d4972595744039 V[0,1]: 201405efa9264f07911db58101903087 V[1,0]: 3e536a998799408a97f3479a6f779d48 V[1,1]: 0d79a7d822a5d215f78c3bf2feb33ae1 V[2,0]: cf8c63d6f2b4563cdd9231107c85950e V[2,1]: 78d17ed7d8d563ff11bd202c76864839 V[3,0]: d7e0707e6bfbbad913bc94b6993a9fa0 V[3,1]: 097e4b1bff40d4c19cb29dfd125d62f2 V[4,0]: a373cf6d537dd66bc0ef0f2f9285359f V[4,1]: c0d0ae0c48f9df3faaf0e7be7768c326 V[5,0]: 9f76560dcae1efacabdcce446ae283bc V[5,1]: bd52a6b9c8f976a26ec1409df19e8bfe
Test Vector 1 key : 000102030405060708090a0b0c0d0e0f 101112131415161718191a1b1c1d1e1f nonce : 101112131415161718191a1b1c1d1e1f 202122232425262728292a2b2c2d2e2f ad : msg : ct : tag128: 62cdbab084c83dacdb945bb446f049c8 tag256: 25d7e799b49a80354c3f881ac2f1027f 471a5d293052bd9997abd3ae84014bb7
Test Vector 2 key : 000102030405060708090a0b0c0d0e0f 101112131415161718191a1b1c1d1e1f nonce : 101112131415161718191a1b1c1d1e1f 202122232425262728292a2b2c2d2e2f ad : 0102030401020304 msg : 04050607040506070405060704050607 04050607040506070405060704050607 04050607040506070405060704050607 04050607040506070405060704050607 04050607040506070405060704050607 04050607040506070405060704050607 04050607040506070405060704050607 0405060704050607 ct : 72120c2ea8236180d67859001f472907 7b7064c414384fe3a7b52f1571f4f8a7 d0f01e18db4f3bc0adb150702e5d147a 8d36522132761b994c1bd395589e2ccf 0790dfe2a3d12d61cd666b2859827739 db4037dd3124c78424459376f6cac08e 1a7223a2a43e398ce6385cd654a19f48 1cba3b8f25910b42 tag128: 635d391828520bf1512763f0c8f5cdbd tag256: b5668d3317159e9cc5d46e4803c3a76a d63bb42b3f47956d94f30db8cb366ad7
AEGIS-256X4 Test Vectors
Initial State key : 000102030405060708090a0b0c0d0e0f 101112131415161718191a1b1c1d1e1f nonce : 101112131415161718191a1b1c1d1e1f 202122232425262728292a2b2c2d2e2f ctx[0]: 00030000000000000000000000000000 ctx[1]: 01030000000000000000000000000000 ctx[2]: 02030000000000000000000000000000 ctx[3]: 03030000000000000000000000000000 After initialization: V[0,0]: 482a86e8436cd2361063a4b2702769b9 V[0,1]: d95a2be81c9245b22996f68eea0122f9 V[0,2]: 0c2a3b348b1a5e256c6751377318c41e V[0,3]: f64436a21653fe7cf2e0829a177db383 V[1,0]: e705e8866267717d96092e58e78b574c V[1,1]: d1dd412142df9806cc267af2fe1d830e V[1,2]: 30e7dfd3c9941b8394e95bdf5bac99d9 V[1,3]: 9f27186f8a4fab86820689822c3c74d2 V[2,0]: e1aa6af5d9e31dde8d94a48a0810fa89 V[2,1]: 63555cdf0d98f18fb75b029ad80786c0 V[2,2]: a3ee0e4a3429a9539e4fcec385475608 V[2,3]: 28ea527d31ef61df498dc107fe02df99 V[3,0]: 37f06808410c8f3954525ae44584d3be V[3,1]: 8fcc23bca2fe2209f93d34e2da35b33d V[3,2]: 33156347df89eaa69ab11096362daccf V[3,3]: bbe58d9dbe8c5b0469be5a87086db5d4 V[4,0]: d1c9eb37fecbc5ada7b351fa4f501f32 V[4,1]: 0b9b803283c1538628b507c8f6432434 V[4,2]: bfb8b6d4f87cce28825c7e92f54b8728 V[4,3]: 8917bb5b09c32f900c6a5a1d63c46264 V[5,0]: 4f6110c2ef0c3c687e90c1e5532ddf8e V[5,1]: 031bd85d99f64684d23728a0453c72a1 V[5,2]: 10bc7ec34d4119b5bdeb6c7dfc458247 V[5,3]: 591ece530aeaa5c9867220156f5c25e3
Test Vector 1 key : 000102030405060708090a0b0c0d0e0f 101112131415161718191a1b1c1d1e1f nonce : 101112131415161718191a1b1c1d1e1f 202122232425262728292a2b2c2d2e2f ad : msg : ct : tag128: 3b7fee6cee7bf17888ad11ed2397beb4 tag256: 6093a1a8aab20ec635dc1ca71745b01b 5bec4fc444c9ffbebd710d4a34d20eaf
Test Vector 2 key : 000102030405060708090a0b0c0d0e0f 101112131415161718191a1b1c1d1e1f nonce : 101112131415161718191a1b1c1d1e1f 202122232425262728292a2b2c2d2e2f ad : 0102030401020304 msg : 04050607040506070405060704050607 04050607040506070405060704050607 04050607040506070405060704050607 04050607040506070405060704050607 04050607040506070405060704050607 04050607040506070405060704050607 04050607040506070405060704050607 0405060704050607 ct : bfc2085b7e8017da99b0b6d646ae4d01 f4ba8f2e7dfca1d759ae48a135139b9a aac6b4f5db810d426be1fdaff4e14541 53a34b11da78ed7e418ee2ee9853042e 95536aecbb694cea1b16a478eb0d4d1b f6509b1ce652a45af58e0e46ffccfa2d 0426e702391d2ff5813808b81748a490 dd656465fed61f09 tag128: b63b611b13975e2f3dc3cb6c2397bfcd tag256: 7847eace74409ee56c8f4cf63a9c2841 ce7c8bd567d7c0ca514c879a190b978c
AEGISMAC Test Vectors
AEGISMAC-128L Test Vector key : 10010000000000000000000000000000 nonce : 10000200000000000000000000000000 data : 000102030405060708090a0b0c0d0e0f 101112131415161718191a1b1c1d1e1f 202122 tag128 : d3f09b2842ad301687d6902c921d7818 tag256 : 9490e7c89d420c9f37417fa625eb38e8 cad53c5cbec55285e8499ea48377f2a3
AEGISMAC-128X2 Test Vector key : 10010000000000000000000000000000 nonce : 10000200000000000000000000000000 data : 000102030405060708090a0b0c0d0e0f 101112131415161718191a1b1c1d1e1f 202122 tags128: 9f5f69928fa481fa86e8a51e072a9b29 eeaa77a356f796b427f6a54f52ae0e20 tag128 : 6873ee34e6b5c59143b6d35c5e4f2c6e tags256: 22cdcf558d0338b6ad8fbba4da7307d3 0bd685fff23dc9d41f598c2a7ea44055 tag256 : afcba3fc2d63c8d6c7f2d63f3ec8fbbb af022e15ac120e78ffa7755abccd959c
AEGISMAC-128X4 Test Vector key : 10010000000000000000000000000000 nonce : 10000200000000000000000000000000 data : 000102030405060708090a0b0c0d0e0f 101112131415161718191a1b1c1d1e1f 202122 tags128: 7fecd913a7cb0011b6c4c88e0c6f8578 19a98fbeaf21d1092c32953fff82c8a9 c7b5e6625a5765d04af26cf22adc1282 4c8cf3b4dbb85f379e13b04a8d06bca7 tag128 : c45a98fd9ab8956ce616eb008cfe4e53 tags256: d595732bdf230a1441978414cd8cfa39 ecef6ad0ee1e65ae530006ca5d5f4481 f9ec5edfa64e9c3d76d3a5eda9fe5bd1 fb9d842373f7c90bedb8bfe383740b23 1264a15143eb8c3d9f17754099f147e3 401c83c0d5afc70fd0d68bfd17f9280f tag256 : 26fdc76f41b1da7aec7779f6e964beae 8904e662f05aca8345ae3befb357412a
AEGISMAC-256 Test Vector key : 10010000000000000000000000000000 00000000000000000000000000000000 nonce : 10000200000000000000000000000000 00000000000000000000000000000000 data : 000102030405060708090a0b0c0d0e0f 101112131415161718191a1b1c1d1e1f 202122 tag128 : c08e20cfc56f27195a46c9cef5c162d4 tag256 : a5c906ede3d69545c11e20afa360b221 f936e946ed2dba3d7c75ad6dc2784126
AEGISMAC-256X2 Test Vector key : 10010000000000000000000000000000 00000000000000000000000000000000 nonce : 10000200000000000000000000000000 00000000000000000000000000000000 data : 000102030405060708090a0b0c0d0e0f 101112131415161718191a1b1c1d1e1f 202122 tags128: db8852ea2c03f22b0d0694ea4e88e4b1 tag128 : fb319cb6dd728a764606fb14d37f2a5e tags256: b4d124976b34b2aa8bc3fa0b55396cf7 fb83f4ef5ba607681cddf5ba3e925727 tag256 : 0844b20ed5147ceae89c7a160263afd4 b1382d6b154ecf560ce8a342cb6a8fd1
AEGISMAC-256X4 Test Vector key : 10010000000000000000000000000000 00000000000000000000000000000000 nonce : 10000200000000000000000000000000 00000000000000000000000000000000 data : 000102030405060708090a0b0c0d0e0f 101112131415161718191a1b1c1d1e1f 202122 tags128: 702d595e74962d073a0d68c883d80deb 41ab207e43b16659d556d7467218a9ec 113406e7cb56e0f6b63c95c88421dfee tag128 : a51f9bc5beae60cce77f0dbc60761edd tags256: a46ebcd10939b42012a3f9b6147172af 3b74aec5d0070e8d6a81498ccbcdb41a d57cd7a50fa8621dfea2e81cd941def5 57094251a24527a4d97fc4c825368180 3973129d07cc20811a8b3c34574f6ce0 10165dd0e856e797f70731e78e32f764 tag256 : b36a16ef07c36d75a91f437502f24f54 5b8dfa88648ed116943c29fead3bf10c
Acknowledgments The AEGIS family of authenticated encryption algorithms was invented by and . The state update function leverages the AES permutation invented by and . They also authored the Pelican MAC, which partly motivated the design of the AEGIS MAC. We would like to thank the following individuals for their contributions:
  • , , and for catching invalid test vectors, and for many helpful suggestions.
  • for his early review of the document and for suggesting the addition of negative test vectors.
  • for his review of the document and for suggesting how AEGIS should be used in the context of DTLS and QUIC.
  • and , as well as and , for investigating the committing security of the schemes specified in this document.
  • for his review of the document as a member of the CFRG Crypto Review Panel.
  • , , and for their review of the document.
  • for reviewing the document and providing insightful comments on the implications of nonce reuse in AEGIS-128X and AEGIS-256X.
  • for taking the time to review the document on behalf of the IRSG.
Authors' Addresses Fastly Inc.
fde@00f.net
Individual Contributor
specifications@samuellucas.com