Technical Specifications

Note
For technical specifications of FIPSFederal Information Processing Standards - standards developed by the United States federal government for use in computer systems by non-military government agencies and government contractors 140-2 certified CORE solution, see CORE FIPS Specifications.

Key Types and Operations

The table below summarizes the supported key types and their operations. The following sections detail supported modes, paddings, and hash algorithms. The key types are grouped in the following classes:

Private Key

Imported or generated private key of an asymmetric key-pair.

Public Key

Imported public key of an asymmetric key-pair.

Secret Key

Imported or generated symmetric key.

Split KeyA split key is a symmetric or a private key that has been split into a number of parts,

A part of symmetric or private key that was split into several parts.

Other

Standard keys optimized by Unbound to provide a specific service. For example, PRF keys are generated and used to provide tokenization services.

Key Class	Type	Size/Curve	Default Size/Curve	Supported Operations	Default Operations
Asymmetric private key	RSA	2048, 3072, 4096	2048	Sign, Decrypt, Unwrap, Derive	Sign, Decrypt, Unwrap
	ECCElliptic-curve cryptography - an approach to public-key cryptography based on the algebraic structure of elliptic curves over finite fields	P256, P384, P521, SECP256K1, CURVE25519, CURVE448	P256		Sign, Derive
Asymmetric public key	RSA	see "Asymmetric private key"		Verify, Encrypt, Wrap
	ECCElliptic-curve cryptography - an approach to public-key cryptography based on the algebraic structure of elliptic curves over finite fields
Symmetric secret key	AES	128, 192, 256	256	Encrypt, Decrypt, Wrap, Unwrap Mac, Mac verify, Derive	Encrypt, Decrypt
	XTS	256, 512	256
	CHACHA20	256	256
	TDES	192	192
	DES	64	64
	HMACHash-based Message Authentication Code - A MAC involving a cryptographic hash function and a secret cryptographic key.	8 to 2048, in increments of 8	128	Mac, Mac verify, Derive
Split key	AES, TDES, HMACHash-based Message Authentication Code - A MAC involving a cryptographic hash function and a secret cryptographic key.	see "Symmetric secret key"		Join
Other	PRF	P256		Derive, Decrypt

Notes:

1. To use a public key of a private key, generate the public key and add it to the partition.
2. "Default size/curve" and "Default operations" specify the size and permitted operations of a key that is created without specifying these properties.
3. CURVE25519 and CURVE448 are Edwards (Ed) keys if the "Supported Operations" are SIGN. They are Montgomery(X) keys if the "Supported Operations" are DERIVE.

Additional Unbound keys:

PWD

Key type: EC P256

Operation: Verify

LIMA

Key size:1024

Operation: Derive

Algorithms

CORE provides the following crypt algorithms.

Supported HASH Options

SHASecure Hash Algorithm - a family of cryptographic hash functions-1, SHASecure Hash Algorithm - a family of cryptographic hash functions-256, SHASecure Hash Algorithm - a family of cryptographic hash functions-384, SHASecure Hash Algorithm - a family of cryptographic hash functions-512, SHA3-256, SHA3-384, SHA3-512.

AES Algorithms

Key sizes: 128, 192, 256.

Operation	Mode	MAC Mode	Hash
Encrypt, Decrypt	ECB, CBC, CFB, OFB, CTR, GCM, CCM, NISTWRAPAES Key Wrap (KW) specified by NIST Special Publication 800-38F
Wrap, Unwrap	See Wrapping with Secret Keys
Mac, Mac verify		CMAC, GMAC
Derive	Hash		Supported HASH Options
	Concatenate
	NISTNational Institute of Standards and Technology-CMAC-CTR

Note:

1. NISTWRAPAES Key Wrap (KW) specified by NIST Special Publication 800-38F (NIST.SP.800-38F) is also indicated as AES-KW (AES Key Wrap mode)

AES-XTS Algorithms

Key Sizes: 256, 512. (Double Keys).

Operation	Mode	Hash
Encrypt, Decrypt	XTS
Derive	Hash	Supported HASH Options
	Concatenate

CHACHA20-Poly1305 Algorithms

Key size:256

Operation	Mode	MAC Mode
Encrypt, Decrypt	CTR	Poly1305
Wrap, Unwrap	CTR	Poly1305

HMAC Algorithms

Key size: 8 to 2048, in increments of 8.

Operation	Mode	Hash
Mac Mac Verify	HMACHash-based Message Authentication Code - A MAC involving a cryptographic hash function and a secret cryptographic key.	Supported HASH Options
Derive	Hash	Supported HASH Options
	Concatenate
	SLIP-10

TDES Algorithms

Key size: 168 (also known as 192).

Operation	Mode	Hash
Encrypt, Decrypt	ECB, CBC, CFB, OFB
Wrap, Unwrap	See Wrapping with Secret Keys
Mac, Mac Verify	CMAC
Derive	Hash	Supported HASH Options
	Concatenate

RSA Algorithms

Key size: 2048, 3072, 4096.

Operation	Padding	Hash	Notes
Sign	PKCSPublic-Key Cryptography Standards - Industry-standard cryptography specifications.#1		1
	PSSprobabilistic signature scheme. Abbreviation of RSASSA-PSS		2
Decrypt	PKCSPublic-Key Cryptography Standards - Industry-standard cryptography specifications.#1
	OAEPOptimal Asymmetric Encryption Padding - A padding scheme often used together with RSA encryption of symmetric keys.	Supported HASH Options	3
	RAWCKM_RSA_X_509 padding mechanism		4
Wrap (using the public key)	PKCSPublic-Key Cryptography Standards - Industry-standard cryptography specifications.#1		5
	OAEPOptimal Asymmetric Encryption Padding - A padding scheme often used together with RSA encryption of symmetric keys.	Supported HASH Options
Unwrap	PKCSPublic-Key Cryptography Standards - Industry-standard cryptography specifications.#1
	OAEPOptimal Asymmetric Encryption Padding - A padding scheme often used together with RSA encryption of symmetric keys.	Supported HASH Options

Notes:

1. PKCSPublic-Key Cryptography Standards - Industry-standard cryptography specifications.#1 is an abbreviation of RSA-PKCSPublic-Key Cryptography Standards - Industry-standard cryptography specifications.#1 v1.5.
2. PSSprobabilistic signature scheme. Abbreviation of RSASSA-PSS is an abbreviation of RSASSA-PSSprobabilistic signature scheme (PSS) with appendix.
3. The default padding for wrapping: OAEPOptimal Asymmetric Encryption Padding - A padding scheme often used together with RSA encryption of symmetric keys..
4. RAWCKM_RSA_X_509 padding mechanism denotes CKM_RSA_X_509 padding.
5. See Wrapping Options.

ECC Algorithms

ECDSAElliptic Curve Digital Signature Algorithm - A variant of the Digital Signature Algorithm (DSA) which uses elliptic curve cryptography.

Operation: Sign

Elliptic curves: P256, P384, P521, SECP256K1, Ed25519, Ed448

ECDHDiffie–Hellman (ECDH) is a key agreement protocol used to establish shared secret by deriving it from EC keys.

Operation: Key derivation

Elliptic curves:  P256, P384, P521, X25519, X448

Notes:

1. To define Edwards Ed25519 or Ed448:
   • use CURVE25519 or CURVE448
   • make sure to specify SIGN among the permitted operations.
2. To define Montgomery X25519 or X448:
   • use CURVE25519 or CURVE448
   • specify DERIVE as the mandatory operation.

   Make sure to delete the SIGN operation from the permitted operations list.

3. Other names used for curves:
   • P256 is known as SECG' secp256r1 and ANSI' prime256v1.
   • P384 is known as SECG' secp384r1.
     See RFC 8422 Appendix A - Equivalent Curves.

Wrapping Options

CORE provides the following key wrapping options: using secret keys and using public keys.

Wrapping with Secret Keys

A Key to be Wrapped	The Wrapping Key (Type and Mode)
	AES	CHACHA20	TDES/DES
AES	ECB, CBC, OFB, CFB, CTR, GCM, CCM, NISTWRAPAES Key Wrap (KW) specified by NIST Special Publication 800-38F	CHACHA20_POLY_1305	ECB, CBC, OFB, CFB
TDES/DES	OFB, CFB, CTR, GCM, CCM, NISTWRAPAES Key Wrap (KW) specified by NIST Special Publication 800-38F	CHACHA20_POLY_1305	ECB, CBC, OFB, CFB
XTS	ECB, CBC, OFB, CFB, CTR, GCM, CCM, NISTWRAPAES Key Wrap (KW) specified by NIST Special Publication 800-38F	CHACHA20_POLY_1305	ECB, CBC, OFB, CFB
CHACHA20	ECB, CBC, OFB, CFB, CTR, GCM, CCM, NISTWRAPAES Key Wrap (KW) specified by NIST Special Publication 800-38F	CHACHA20_POLY_1305	ECB, CBC, OFB, CFB
HMACHash-based Message Authentication Code - A MAC involving a cryptographic hash function and a secret cryptographic key.	ECB, CBC, OFB, CFB, CTR, GCM, CCM, NISTWRAPAES Key Wrap (KW) specified by NIST Special Publication 800-38F	CHACHA20_POLY_1305	OFB, CFB
RSA	OFB, CFB, CTR, GCM, CCM, NISTWRAPAES Key Wrap (KW) specified by NIST Special Publication 800-38F	CHACHA20_POLY_1305	OFB, CFB
EC	OFB, CFB, CTR, GCM, CCM, NISTWRAPAES Key Wrap (KW) specified by NIST Special Publication 800-38F	CHACHA20_POLY_1305	OFB, CFB

Note:

1. AES-KW (AES Key Wrap mode) and AES-KWP (AES Key Wrap with Padding) are indicated here as NISTWRAPAES Key Wrap (KW) specified by NIST Special Publication 800-38F (NIST.SP.800-38F).

Wrapping with Public Keys

Keys that may be wrapped using Public RSA key:

AES

XTS

CHACHA20

HMACHash-based Message Authentication Code - A MAC involving a cryptographic hash function and a secret cryptographic key.

TDES/DES

Padding options:

OAEPOptimal Asymmetric Encryption Padding - A padding scheme often used together with RSA encryption of symmetric keys. (default) and mandatory specification of one of the Technical Specifications and the corresponding MGFMask Generation Function - A cryptographic primitive similar to a hash function except that it supports output of a variable length..

PKCSPublic-Key Cryptography Standards - Industry-standard cryptography specifications.#1

Interoperability

Cloud Keystores

Cloud keystore	SDK name	SDK version	CORE specification
AWS KMSKey Management System	aws-java-sdk-kms	1.11.682	AWS KMS
Azure Key Vault	azure-keyvault	1.2.4	Azure Key Vault
GCP KMSKey Management System	google-cloud-kms	1.43.0	Google Cloud KMS

On-premises HSMs

On-premises HSMHardware Security Module - a physical computing device that safeguards and manages digital keys for strong authentication and provides cryptoprocessing vendor	HSMHardware Security Module - a physical computing device that safeguards and manages digital keys for strong authentication and provides cryptoprocessing model	HSMHardware Security Module - a physical computing device that safeguards and manages digital keys for strong authentication and provides cryptoprocessing client version	CORE specification
Thales	Safenet Luna	7.4	HSM - Luna
Entrust (nCipher)	nShield Connect HSMHardware Security Module - a physical computing device that safeguards and manages digital keys for strong authentication and provides cryptoprocessing	12.71.0	HSM - nCipher

OIDC Providers

• Microsoft Identity Platform v2.
• Amazon Cognito.
• Google Cloud Identity Platform.
• Ping Identity.

Crypto Client Options

Applications interact with the CORE solution in one of the following ways:

Without client-side installation:

• Using CORE RESTRepresentational State Transfer (REST) - an architectural style that defines a set of constraints and properties based on HTTP. Web Services that conform to the REST architectural style, or RESTful web services, provide interoperability between computer systems on the Internet. API.
• Using CORE ClientlessSystem that is using Unbound Java Security Provider without dependency on the UKC Client software. JCAJava Cryptography Architecture - Java frameworks for implementing cryptography primitives. provider API.
• Using KMIPKey Management Interoperability Protocol - an extensible communication protocol that defines message formats for the manipulation of cryptographic keys on a key management server Protocol client-side (1.1 and later). See KMIP Conformance.

Using CORE Client software installed on device:

• PKCSPublic-Key Cryptography Standards - Industry-standard cryptography specifications. #11
• OpenSSL
• Microsoft CNG and CSP
• Java JCEJava Cryptography Extension - Java frameworks for implementing cryptography primitives. - CORE Client-based JCAJava Cryptography Architecture - Java frameworks for implementing cryptography primitives. provider

Applications and Development

For integration with external keystores, see Keys in External Keystores.

For integration with other applications, see Integration Guide and Code Signing Guide.

For integration into applications, see Developer's Guide, and CORE REST API.

Platform Specifications

For CORE server architecture and OS requirements, see CORE Server Requirements.

For CORE client architecture and OS requirements, see CORE Client Requirements.

System Capacity Default Constraints

The following maximum values are the CORE default capacity constraints per system, partition, and operation. Before increasing any of these, contact support@unboundsecurity.com.

Maximum Number of	Per System	Per Partition
Server pairs in a cluster	12
Auxiliary servers	12
Partitions	3,000
OIDCOpenID Connect is identity layer on top of the OAuth 2.0 protocol Providers	8
External Key Stores	12,000	10
Crypto objects	500,000	100,000
Clients	10,000	1,000
Users	10,000	1,000
User groups	10,000	1,000
User roles	10,000	1,000
Statements in Partition Policy	1,000	30
Quorum requests in DB(*)	1,000	30
Backup records	3,000

Note: "Quorum request in DB" refers to both pending and approved requests that are kept in the database. As needed, consider deleting the approved requests.

Maximum Size in Bytes	Per Crypto Operation
Crypto payload size	< 4000

Note: For example, max size of a secret that can be accepted by the system.