About FIPS 140-2 Compliance in Kong Gateway

The Federal Information Processing Standard (FIPS) 140-2 is a federal standard defined by the National Institute of Standards and Technology. It specifies the security requirements that must be satisfied by a cryptographic module. The FIPS Kong Gateway package is FIPS 140-2 compliant. Compliance means that Kong Gateway only uses FIPS 140-2 approved algorithms while running in FIPS mode, but the product has not been submitted to a NIST testing lab for validation.

Kong Enterprise provides a FIPS 140-2 compliant package for Ubuntu 20.04, Ubuntu 22.04, and Red Hat Enterprise 8. This package provides compliance for the core Kong Gateway product and all out of the box plugins .

The package replaces OpenSSL, the primary SSL library in Kong Gateway, with BoringSSL, which at its core uses the FIPS 140-2 validated BoringCrypto for cryptographic operations.

FIPS implementation

Password hashing

The following table describes how Kong Gateway uses key derivation functions:

ComponentNormal modeFIPS modeNotes
core/rbacbcryptPBKDF2 1PBKDF2 in BoringSSL isn’t FIPS validated.
plugins/oauth2 2Argon2 or bcrypt (when hash_secret=true)Disabled (hash_secret can’t be set to true)PBKDF2 in BoringSSL isn’t FIPS validated.
plugins/key-auth-enc 3SHA1SHA256SHA1 is read-only in FIPS mode.

[1]: As of Kong Gateway FIPS 3.0, RBAC uses PBKDF2 as password hashing algorithm.

[2]: As of Kong Gateway FIPS 3.1, the oauth2 plugin disables hash_secret feature, so the user can’t turn it on. This means password will be stored plaintext in the database; however, users can choose to use secrets management or db encryption instead.

[3]: As of Kong Gateway FIPS 3.1, key-auth-enc uses SHA1 to speed up lookup of a key in DB. As of Kong Gateway FIPS 3.2, SHA1 support is “read-only”, meaning existing credentials in DB are still validated, but any new credentials will be hashed in SHA256.

Important: If you are migrating from Kong Gateway 3.1 to 3.2 in FIPS mode and are using the key-auth-enc plugin, you should send PATCH or POST requests to all existing key-auth-enc credentials to re-hash them in SHA256.

Non-cryptographic usage of cryptographic algorithms

FIPS only defines the approved algorithms to use for each specific purpose, so FIPS policy doesn’t explicitly restrict the usage of cryptographic algorithms to only cases where they are necessary.

For example, using SHA256 as the message digest algorithm is approved while using MD5 is not. But that doesn’t mean MD5 can’t exist in the application at all. For example, the FIPS 140-2 approved BoringSSL version allows MD5 when it’s used with the TLS protocol version 1.0 and 1.1.

The following table explains where cryptographic algorithms are used for non-cryptographic purposes in Kong Gateway:

ComponentNormal modeFIPS modeNotes
core/balancerxxhash32xxhash32Use to generate a unique identifier.
core/balancercrc32crc32crc32 isn’t message digest.
core/uuidLua random number generatorLua random number generatorThe RNG isn’t used for cryptographic purposes.
core/declarative_config/uuidUUIDv5 (namespaced SHA1)UUIDv5 (namespaced SHA1)Used to generate a unique identifier.
core/declarative_config/config_hash and core/hybrid/hashesMD5MD5Used to generate a unique identifier.

SSL client

FIPS 140-2 only mentioned SSL server, which is already supported in Kong Gateway FIPS 3.0. FIPS specification isn’t designated for SSL clients, so there isn’t specific handling of these in Kong Gateway.

This includes:

  • Using Lua to talk in HTTPS and PostgreSQL SSL
  • Using an upstream that proxies in HTTPS