This document describes HiPay’s cryptographic policy. It is intended for technical staff or IT service providers.

SSL/TLS protocols and cipher suites implemented by HiPay are described hereafter.

Impending changes to HiPay’s cryptographic policy are also indicated as a warning.

Please note that some of these changes are outside of HiPay’s control and may be enforced by contractual or legal obligations.

TLS 1.0 support is a prime example, as it must be dropped by the end of June 2018 at the very latest, in compliance with PCI DSS requirements.

The information contained in this document is non-binding and subject to change, as the cryptographic scene evolves.

Please refer to the information on the POODLE attack for more details on how such situations may arise.

Acronyms and glossary of terms

RFC 2119 key words

Should they appear hereafter, the key words “MUST”, “MUST NOT”, “REQUIRED”, “SHALL”, “SHALL NOT”, “SHOULD”, “SHOULD NOT”, “RECOMMENDED”, “MAY”, and “OPTIONAL” in this document are to be interpreted as described in RFC 2119 / BCP 14.

Acronyms

AEAD: Authenticated Encryption with Associated Data
AES: Advanced Encryption Standard (as per FIPS publication 197)
APT: Advanced Persistent Threat, typically state-sponsored agencies with million-dollar resources
DH: Diffie-Hellman
DH params: Diffie-Hellman parameters used for the initial key exchange in cryptographic communications
EC: Elliptic Curve
GCM: Galois/Counter Mode
KEX: Key EXchange
MAC: Message Authentication Code
MITM: Man In The Middle – i.e., the attacker who gets between the client and the server to intercept traffic
SSL: Secure Sockets Layer
TLS: Transport Layer Security

Diffie-Hellman acronyms

DHE: Diffie-Hellman Ephemeral (same as EDH)
ECDHE: Elliptic Curve Diffie-Hellman Ephemeral (same as EECDH)
EDH: Ephemeral Diffie-Hellman (same as DHE)
EECDH: Ephemeral Elliptic Curve Diffie-Hellman (same as ECDHE)

Glossary of terms

HiPay Enterprise: Advanced single solution designed to handle all your online payment needs
HiPay’s tokenization servers: System allowing merchants to submit credit card data and get a secure token in return
HiPay Professional: Platform created for start-ups and growing businesses to simplify integration and provide online payments in a few clicks
Soft-cut: Soft cut-off date for a given protocol or cipher suite (date on which we would like to implement the change)
Hard-cut: Hard cut-off date for a given protocol or cipher suite (date on which, no matter what, the protocol or cipher suite will have to be disabled by HiPay)

Key words for changes

Discourage: The use of a given cipher will be discouraged by moving it down the list, making it less likely that a client will use it when connecting to HiPay’s systems
Drop: A given protocol or cipher suite will stop being supported entirely
Implement: A given protocol or cipher suite will be added to the list of supported protocols or cipher suites
Keep: A given protocol or cipher suite will keep on being supported, with no changes
Monitor: A given protocol or cipher suite is considered brittle, vulnerable or soon to be deprecated and will be kept closely monitored

Deciphering cipher suites

Cipher suites handle privacy (i.e., the encryption of data) and integrity (i.e., the signature/hashing of data).

Cipher suites are typically written as follows:

[SSL|TLS]_[KEX]_[SIG]_WITH_[CIPHER]_[HASH]

The following cipher suite

TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384

gets translated as:

Use Transport Layer Security.
Initiate key exchange with Elliptic Curve Diffie-Hellman Ephemeral.
Sign the initial KEX with Elliptic Curve Digital Signature Algorithm.
Encrypt data with 256-bit Advanced Encryption Standard in Galois/Counter Mode.
Authenticate data with 386-bit Secure Hash Algorithm.

HiPay tries to prefer Elliptic Curve cipher suites, which offer better performance.

HiPay tries to prefer Ephemeral cipher suites, which offer Perfect Forward Secrecy.

HiPay tries to prefer AEAD cipher suites, which are stronger and harder to implement incorrectly in cryptographic libraries.

Whenever possible, HiPay will prefer ChaCha20-Poly1305 over AES256-GCM-SHA*.

AES in Galois/Counter Mode is prone to implementation errors wherein a single nonce reuse breaks the entire cryptosystem.

Cryptographic protocols

HiPay supports the following Transport Layer Security protocols.

Diffie-Hellman parameters

The classic Diffie-Hellman (DH1024, DH2048, etc.) are not supported. Only Ephemeral Diffie-Hellman (DHE) and Elliptic curve Diffie-Hellman Ephemeral (ECDHE) are supported in order to enable Perfect Forward Secrecy.

Cipher suites

HiPay supports the following cipher suites.

The lists below only show supported ciphers, not the order in which they are sent to clients.

Cipher suites – HiPay’s tokenization servers

CHACHA20-POLY1305-SHA256

AES128-CCM-8-SHA256

AES128-CCM-SHA256

ECDHE-RSA-AES256-GCM-SHA384

ECDHE-RSA-AES256-SHA384

DHE-RSA-CHACHA20-POLY1305-SHA256

DHE-RSA-AES256-GCM-SHA384

DHE-RSA-AES256-SHA256

AES256-GCM-SHA384

AES256-SHA256

ECDHE-RSA-CHACHA20-POLY1305-SHA256

ECDHE-RSA-AES128-GCM-SHA256

ECDHE-RSA-AES128-SHA256

DHE-RSA-AES128-GCM-SHA256

DHE-RSA-AES128-SHA256

AES128-GCM-SHA256

AES128-SHA256

Cipher suites – HiPay Enterprise

CHACHA20-POLY1305-SHA256

AES128-CCM-8-SHA256

AES128-CCM-SHA256

ECDHE-RSA-AES256-GCM-SHA384

ECDHE-RSA-AES256-SHA384

DHE-RSA-CHACHA20-POLY1305-SHA256

DHE-RSA-AES256-GCM-SHA384

DHE-RSA-AES256-SHA256

AES256-GCM-SHA384

AES256-SHA256

ECDHE-RSA-CHACHA20-POLY1305-SHA256

ECDHE-RSA-AES128-GCM-SHA256

ECDHE-RSA-AES128-SHA256

ECDHE-RSA-AES128-SHA

DHE-RSA-AES128-GCM-SHA256

DHE-RSA-AES128-SHA256

AES128-GCM-SHA256

AES128-SHA256

Cipher suites – HiPay Professional

CHACHA20-POLY1305-SHA256

AES128-CCM-8-SHA256

AES128-CCM-SHA256

ECDHE-RSA-AES256-GCM-SHA384

ECDHE-RSA-AES256-SHA384

DHE-RSA-CHACHA20-POLY1305-SHA256

DHE-RSA-AES256-GCM-SHA384

DHE-RSA-AES256-SHA256

AES256-GCM-SHA384

AES256-SHA256

ECDHE-RSA-CHACHA20-POLY1305-SHA256

ECDHE-RSA-AES128-GCM-SHA256

ECDHE-RSA-AES128-SHA256

DHE-RSA-AES128-GCM-SHA256

DHE-RSA-AES128-SHA256

AES128-GCM-SHA256

AES128-SHA256

Impending changes

This section references the upcoming changes to HiPay’s cryptographic support.

Changes – SSL/TLS protocols

This subsection covers changes to the support of SSL/TLS protocol versions.

Changes – Key exchange

This subsection covers changes to the support of initial key exchange parameters during SSL/TLS negotiations.

Changes – Cipher suites

This subsection covers changes to HiPay’s supported cipher suites for encryption and message integrity mechanisms over SSL/TLS connections.

SSL/TLS test links

HiPay offers merchants several links to test their SSL/TLS implementation.

Please note that these links do not work like our staging and pre-production systems, they do not offer the possibility to test transactions.

They merely allow you to ensure that your tools can negotiate a TLS protocol and associated ciphers with HiPay.

TLS 1.3

This vhost implements the final version of TLSv1.3 as per RFC8446:

https://tlsv13-ssl.hipay.com/

DH prime fields

Please use the following links to test your ability to connect to HiPay when using 2048 and 4096 bit DH primes:

https://dh2k-ssl.hipay.com/

https://dh4k-ssl.hipay.com/

HiPay's platforms

Please use the following links to test your ability to connect to our Tokenization, Enterprise and Professional servers.

Tokenization servers: https://token-ssl.hipay.com/

HiPay Enterprise servers: https://gateway-ssl.hipay.com/

HiPay Professional servers: https://wallet-ssl.hipay.com/

Getting help and technical support

Should you have any questions or need help interpreting this document, please do not hesitate to contact HiPay by submitting a request through our Support Center.