Cryptographic Calculator – Keys menu
Introduction
The EFTtools set consist of applications supporting payment transaction service development, testing and benchmarking. It currently consists of following components: Cryptographic Calculator and HSM Commander.
This tutorial focuses on Cryptographic Calculator functionality and is provided in six separated parts as per functionality topics covered by its main menu – Generic, Cipher, Keys, Payments, EMV and Development tools. This tutorial also aspires to provide bits of basic history on algorithms in use.
Keys Cryptography
This set of tools focuses on working with keys generation and validation related to their practical usage.
Keys DEA
Have you ever been looking for DEA key generator? A way how to combine a key from multiple components? Or found yourself in a need of checking key’s parity & generating key check value (KCV)? Then this tool does all of this for you: Generates cryptographic keys, allows users to XOR key combination and do a key validation. Key generator uses libGcrypt library and it’s powerful random number generator set to level GCRY_STRONG_RANDOM. This setting is strong enough for all random number requirements.
Key Generator
The Key generator make use of so-called entropy gathering modules built-in your operation system and all operations are being carried in a secured memory allocated specially for this feature with SECMEM settings. This generator is suitable for any test to production system key generation as being reliable and well secured. All keys are generated with a Checksum value so their lodgement in a payment system can be immediately validated.
Options available are a number of keys to generate, final key length and key parity forcing option. Keys to generate option allows generating up to 1000 random keys, which might be handy for generating large batches of terminal keys etc. Key length option provides generation algorithm with key’s output length. Values 64-bit (16H), 128-bit (32-H), 192-bit (48H) and 256-bit (64H) correspond key standard having key lengths defined as Single, Dual, Triple and 256-bit. The last option – Key parity tells application whether some parity should be forced on a key generated. Dual key length and Odd parity are default settings.
Output from this screen should read like this:
DEA Keys: Key generation finished
****************************************
Key length: Dual
Key parity: Right odd
Keys generated: 3
—————————————-
Key #1: C8491F643B9E6D01401C9143D0F275C4
KCV: 77D872
Key #2: EAB93D3D4F5123FE792FF4B9E07CF84A
KCV: 9D7D46
Key #3: AD401F4FDA894A324C68267357FE9215
KCV: 4A5000
Key Combination
The second tab “Key combination” enables users to combine (XOR) up to 9 keys. This feature is handy for forming a key from several components. Even this screen allows up to 9 components to be used only first two are compulsory for key operation. Application for will also guard that the keys have all input digits as hexadecimals (0-9 | A-F) and that key lengths are 16, 32, 48 or 64 characters.
Output from this screen should read like this:
DEA Keys: Key combination operation finished
****************************************
Key component #1: B02310D37A8A9D7952C1C1D5F8F73D61
KCV: FAE09C
Key component #2: 9D4FEF8C75DAE3FDBCD3BF899E196E20
KCV: 1B26EC
—————————————-
Combined key: 2D6CFF5F0F507E84EE127E5C66EE5341
KCV: E1EDFE
Parity enforcement
Sometimes you might find your keys need to be of some parity to continue with another calculation. So we prepared an easy screen that modifies your key to meet the requested parity check.
Output from this screen should read like this:
DEA Keys: Key validation finished
****************************************
Key: B02310D37A8A9D7952C1C1D5F8F73D61
Key length: 32
Parity enforced: Even
New key: B12211D27B8B9C7853C0C0D4F9F63C60
KCV: FAE09C
Validation
The last tab “Validation” provides a basic check to be carried on a key provided. Application will check whether it can detect any parity and will also generate appropriate key Checksum. Application input is again limited to hexadecimal digits (0-9 | A-F) and that key lengths allowed are 16, 32, 48 or 64 characters.
Output from this screen should read like this:
DEA Keys: Key validation finished
****************************************
Key: B02310D37A8A9D7952C1C1D5F8F73D61
Key length: 32
Parity detected: Odd
KCV (VISA): FAE09C
KCV (IBM): 25EF
KCV (ATALLA): FAE09C
KCV (FUTUREX): E24E
KCV (ATALLA R): 188E
——————–
KCV (SHA256): E24C8E
KCV (CMAC): FEA4FE
KCV (AES): 3980EA
DEA Keys: Key validation finished
****************************************
Key: B02310D37A8A9D7952C1C1D5F8F73D65
Key length: 32
Parity detected: No parity
KCV (VISA): 2D8C08
KCV (IBM): F194
KCV (ATALLA): 2D8C08
KCV (FUTUREX): 30E4
KCV (ATALLA R): CCF1
——————–
KCV (SHA256): 8A715F
KCV (CMAC): 490C4E
KCV (AES): DEFD3D
DEA Keys: Key validation finished
****************************************
Key: 6C4DF909186C9CEE39AFD466A6A62D72
Key length: 32
Parity detected: Even
KCV (VISA): 3A4220
KCV (IBM): 8344
KCV (ATALLA): 3A4220
KCV (FUTUREX): 9775
KCV (ATALLA R): AE36
——————–
KCV (SHA256): A1A0C1
KCV (CMAC): B50AA5
KCV (AES): B1D853
Keyshare Generator
Allows insecure and Secure option for a key splitting. Note that all ‘secure’ operations are happening in a PA:DSS compliant memory container and your operation won’t leave any trace in a system when finished.
Keys HSM
Developing a payment system employing the Hardware Security Modules (HSMs) can sometimes prove challenging. Whilst in production HSMs provide a priceless service, in testing and development environments having a black box where cryptography is silently performed can make it hard to diagnose issues since ensuring the correct keys are loaded is an issue. Now with BP-Cryptographic Calculator you can easily check the loaded keys.
Keys Futurex
Key Encryption/Decryption
Encrypts/ Decrypts provided key under a Futurex test MFK and its modifier.
Futurex Keys: Key encryption finished
****************************************
Plain Key: 4090670C3EE229C3E9BAA71EC0BCB974
Parity detected: No parity
MFK: D2DE5CD9110F4CAB11111111111111110123456789ABCDEF
Key modifier: 4
Encrypted Key: BFB1FB2768ED622EC7E923992C6F4A44
KCV: DED19A
The following figure shows this in action:
Key Lookup
Tries to decrypt provided key under all Test MFKs and find a match with KCV value or parity.
Futurex Keys: Lookup finished – 217 records found matching filter criteria
****************************************
Input Key: 4090670C3EE229C3E9BAA71EC0BCB974
Input KCV: Not checked
Input Parity: Any
—————————————-
MFK [Modifier]: Plain key KCV Parity
MFK single [00]: FB44403370B3E3822C79AEBEB9436E40 4C0CD2 No parity
KEK single [00]: 47A647689869C42969E37519AD5D5756 87B95D No parity
MFK double [00]: 70CF6478F6F55F6E98A7365262F933CE C5D708 No parity
KEK double [00]: 6DDA764A3F26B5AC8E4DD813A06362BD A66979 No parity
MFK triple [00]: E2F60DBA0B85234BB8294778A9270623 7E9311 No parity
KEK triple [00]: 9EF86E6CDE9AB64FE7BCF4075FF4F43D 7A83FA No parity
MFK single [00]: BAF3360C5ED84B1F420AF5B6652B7A07 12ADD9 No parity
MFK single [01]: 4FC633DD0783F8C16D874C02E691B0E7 9E793B No parity
KEK single [01]: 8C871084DB62A79DA6B5D18331741227 BED558 No parity
MFK double [01]: 4E0D9628642BB073A949F1E1B17B29B6 7CE8EE No parity
KEK double [01]: 0A28F9F148CCDE7CA93C50FD7F6A996C B7B140 No parity
MFK triple [01]: D6E65EC0E3F72F19D7DA668A0F87BFA7 BA0C6D No parity
KEK triple [01]: ACE46163908ED8D620E4B4A788B2D51B 5C3230 No parity
MFK single [01]: 3B040B6FCCB2B9B64FD5DE748E6EEE5F 0E7C89 No parity
MFK single [02]: F082B204850536F3D49095892AC4CEB3 CD3188 No parity
KEK single [02]: 941F5BFB13ABA84C1E5CCBB225F8ADE5 3F09DA No parity
MFK double [02]: 8BD7DCD035E989D1866218FD98707964 60062E No parity
…
BP-Cryptographic Calculator also includes an option to log all operations performed that can be useful when looking for a key and not knowing the KCV, just knowing the parity or even better not knowing anything. From the experience of the EFTlab team in testing, it’s frequently found that test keys are not randomly generated, but are more likely a sequence of hexadecimal digits, making them easy to spot. This functionality is demonstrated in the figure below:
Keys Microfocus (HPE Atalla)
Key Encryption
Encrypts provided working key under a HP Atalla test MFK.
HP Keys: Key encryption finished
****************************************
Plain Key: 4090670C3EE229C3E9BAA71EC0BCB974
KCV (S): 6C3C
Parity detected: No parity
AKB header: 1PUNE000 [Valid]
Plain MFK Key: 2ABC3DEF4567018998107645FED3CBA20123456789ABCDEF
—————————————-
AKB header: 1PUNE000
Key under MFK: 26AFF233B421666DF88562CC5DF38E6B798CB61F0F7D37EC
MAC: AB7926DB83DAE2D2
AKB: 1PUNE000,26AFF233B421666DF88562CC5DF38E6B798CB61F0F7D37EC,AB7926DB83DAE2D2
The following figure shows this in action:
AKB Decode
Tries to decrypt provided Atalla Key Buffer (AKB) from under test MFK and find a match with KCV value or parity.
HP Keys: Lookup finished
****************************************
AKB: 1PUNE000,D3266EC69C61820019F4A9640A8F603DA14F78E154C7522D,55720A06F8964B8F
Header: 1PUNE000 [Valid]
Key: D3266EC69C61820019F4A9640A8F603DA14F78E154C7522D
MAC: 55720A06F8964B8F [Valid]
Input KCV: 3BAF
Input Parity: Any
—————————————-
Plain key: 0000000055556666
KCV (S): 3BAF
Parity: Even
Keys Gemalto SafeNet
Key Encryption/Decryption
Encrypts / Decrypts provided SafeNet Host-stored key under a SafeNet test KM and its modifier.
SafeNet Keys: Key encryption finished
****************************************
Plain Key: 4090670C3EE229C3E9BAA71EC0BCB974
KCV: 6C3CD4
Key format: 11 – Double-length DES3 (ECB Encrypted)
Plain KM Key: AAAAAAAAAAAAAAAA1111111111111111
KM variant: 00 – DPK
KM (variant applied):AAAAAAAAAAAAAAAA1111111111111111
—————————————-
Encrypted Key: 49B53658EF017B9FDA79CA447EB27A0D
KCV: 587655
Parity detected: No parity
Host-stored Key: 111149B53658EF017B9FDA79CA447EB27A0D
The following figure shows this in action:
Key Lookup
Tries to decrypt provided SafeNet Host-stored key under test KM and find a match with KCV value or parity.
SafeNet Keys: Lookup finished – 34 records found matching filter criteria
****************************************
Input Key: 1113AFD9FD6D4C1B83B98FAE02D1900E2955
Input KCV: Not checked
Input Parity: Any
—————————————-
Variant [Type]: Plain key KCV Parity Desc.
00 [1113]: 722737E2FCC3238690143EA428B370DF 0B91E9 No parity DPK
01 [1113]: B153759D6D0DF4D824E0C06A798E74EB 23D7BB No parity PPK
02 [1113]: FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF CAAAAF Even MPK
03 [1113]: 738B993D7164F52EF244EDF3BC0F9350 1A599F No parity KIS
04 [1113]: 9EB697AF5B918318336C6E6E093DECB8 D4843C No parity KIR
05 [1113]: 70875FA3D55B4CA2FECC591E9CBBFE38 155C1C No parity KTM
06 [1113]: F7C78CC32756A6FF796F59AEA2B13AEA AFC2DA No parity CSCK
07 [1113]: 56F3CA5819B6DF9BF5E9FEC42CA9B0C5 F7284F No parity KPV, DT
08 [1113]: B7760EC907C975F293C143B82FBFD506 729607 No parity KPVV
09 [1113]: F14D8AFA5F879FF5FC4B0EC87A60565C E4069C No parity KCVV
10 [1113]: 893F353058C1C5B1B2B535F3452FBD27 3C5A62 No parity KI
12 [1113]: B7667AEC047C14AB35BFDAD99CFC6F01 85A395 No parity MAC Residue
…
BP-Cryptographic Calculator also includes an option to log all operations performed that can be useful when looking for a key and not knowing the KCV, just knowing the parity or even better not knowing anything. From the experience of the EFTlab team in testing, it’s frequently found that test keys are not randomly generated, but are more likely a sequence of hexadecimal digits, making them easy to spot. This functionality is demonstrated in the figure below:
Keys Thales
Key Encryption/Decryption
Developing a payment system employing the Thales Hardware Security Modules (HSMs) can sometimes prove challenging. Whilst in production HSMs provide a priceless service, in testing and development environments having a black box where cryptography is silently performed can make it hard to diagnose issues since ensuring the correct keys are loaded is an issue. Now with BP- Cryptographic Calculator you can easily check the loaded keys.
Firstly the Thales HSM allows configuration of up to 20 Local Master Keys (LMKs). To reduce the risk of a key becoming compromised Thales employs five schemes and seven variants. These are represented by a binary mask used atop the key prior to use in cryptographic operations. Using the appropriate key results in key pair selection, a XOR operation with the scheme and finally another XOR with a key variant. Simply said out of the original 20 keys there can be 700 completely different keys for any cryptographic purpose.
However setting a key under the LMK, scheme, variant or retrieving a key is intentionally complex. This is why EFTlab have developed the Thales key encoding and decoding functionality for the default Thales key set.
Thales Keys: Key encryption finished
****************************************
Plain Key: B02310D37A8A9D7952C1C1D5F8F73D61
Key scheme: U
Key length: 32
Parity detected: Odd
LMK Pair: 00-01: 01010101010101017902CD1FD36EF8BA
LMK Variant: 1
Encrypted Key: 85A498E630E7B900C508589CE2B0C992
KCV: 85B866
The following figure shows this in action:
Key Lookup
When working with Thales HSMs in development developers and testers often need to verify keys to ensure a system is processing correctly. Payment systems are often full of keys making it difficult to find what parameters are being used for their decryption to reveal their clear value. Usually what’s left is just a key preceded with a scheme letter and checksum (KCV) of hidden key; how can developers and testers reveal the original key?
In short there are two ways; the first (and quickest) is to search through documentation hoping for a lucky draw. The second is to brute force using all available HSM keys, their schemes and variants to attempt to reveal key candidates and follow with KCV operation on top of those. Whilst hypothetically brute-force operations should just take too long, we have prepared a tool making this possible on an environment where the default Thales key sets are loaded. As demonstrated on the figure below, with BP-Cryptographic Calculator it takes only a few milliseconds to reveal the clear key.
Thales Keys: Lookup finished – Match found
****************************************
Input Key: U227AA70949A9D254638E79950C3AF770
Input KCV: BA9B76
Input Parity: Odd
—————————————-
LMK pair [Variant]: Plain key KCV Parity
14-15 [5]: 7538A1F161E00B26AE2C80E0C4B99DA4 BA9B76 Odd
BP-Cryptographic Calculator also includes an option to log all operations performed that can be useful when looking for a key and not knowing the KCV, just knowing the parity or even better not knowing anything. From the experience of the EFTlab team in testing, it’s frequently found that test keys are not randomly generated, but are more likely a sequence of hexadecimal digits, making them easy to spot. This functionality is demonstrated in the figure below:
Key Blocks
Cryptographic Key Blocks – the use of cryptographic key blocks for the secure exchange of keys is a means of using one or more blocks to bind key parts with information about the resulting key – e.g., an identifier, a purpose/function code, or an origin authenticator. The use of cryptographic key blocks, especially as it applies to Triple Data Encryption Algorithm (TDEA) keys, is known as key bundling; however, more generally, it includes key wrapping.
Thales Key Block
The Thales key block mechanism is based on, but refines and extends, the TR-31 key block that has been standardized for key exchange between communicating parties.
The key types that may be included in a Thales key block are DES and 3-DES keys, HMAC keys and RSA public and private keys. Note that an RSA public key is not encrypted, but the key block is still authenticated.
Thales Key Block: Key block encrypt operation finished
****************************************
KBPK: 9B71333A13F9FAE72F9D0E2DAB4AD6784718012F9244033F3F26A2DE0C8AA11A
Plain Key: 0123456789ABCDEFFEDCBA9876543210
—————————————-
Header: 10096B0TN00E0002
Encrypted key: D87DC769C95B18C8017242E4B561E9774FB2039ED4F621776752866E1640FE1D
MAC: 39EE161BB3732437
—————————————-
Thales Key Block: 10096B0TN00E0002D87DC769C95B18C8017242E4B561E9774FB2039ED4F621776752866E1640FE1D39EE161BB3732437
Thales Key Block: Key block decode operation finished
****************************************
KBPK: 9B71333A13F9FAE72F9D0E2DAB4AD6784718012F9244033F3F26A2DE0C8AA11A
Thales Key block: S10096B0TN00E0002D87DC769C95B18C8017242E4B561E9774FB2039ED4F621776752866E1640FE1D39EE161BB3732437
—————————————-
Thales Header: 10096B0TN00E0002
—————————————-
Version Id: 1
Block Length: 0096
Key Usage: B0
Algorithm: T
Mode of Use: N
Key Version No.: 00
Exportability: E
Num. of Opt. blocks: 00
LMK ID: 02
Optional Blocks:
Thales Encrypted key: D87DC769C95B18C8017242E4B561E9774FB2039ED4F621776752866E1640FE1D
Thales MAC: 39EE161BB3732437
—————————————-
Plain Key: 0123456789ABCDEFFEDCBA9876543210
KCV: 08D7B4
TR-31 Key Block
A TR-31 key block is a format defined by the American National Standards Institute (ANSI).
The TR-31 key block supports the interchange of keys in a secure manner with key attributes included in the exchanged data.
The TR-31 key block format has a set of defined key attributes that are securely bound to the key so that they can be transported together between any two systems that both understand the TR-31 format.
TR-31 Key Block: Key block encrypt operation finished
****************************************
KBPK: 89E88CF7931444F334BD7547FC3F380C
Header: A0072B0TN00E0000
Plain Key: F039121BEC83D26B169BDCD5B22AAF8F
—————————————-
TR-31 Key Block: A0072B0TN00E000019E69B17C0ED2E61584FB10150B1698625735EA73BA51389EDDF5836
TR-31 Key Block: Key block decode operation finished
****************************************
KBPK: 89E88CF7931444F334BD7547FC3F380C
TR-31 Key block: A0072P0TE00E0000F5161ED902807AF26F1D62263644BD24192FDB3193C730301CEE8701
—————————————-
TR-31 Header: A0072P0TE00E0000
—————————————-
Version Id: A
Block Length: 0072
Key Usage: P0
Algorithm: T
Mode of Use: E
Key Version No.: 00
Exportability: E
Num. of Opt. blocks: 00
Reserved: 00
Optional Blocks:
TR-31 Encrypted key: F5161ED902807AF26F1D62263644BD24192FDB3193C73030
TR-31 MAC: 1CEE8701
—————————————-
Plain Key: F039121BEC83D26B169BDCD5B22AAF8F
SSL Certificates
See a separate tutorial SSL Certificates with BP-CCalc.
Summary
In this article, we went through the functionality of Cryptographic Calculator covered by the Keys Menu.
Cryptographic Calculator and other tools covered in EFTtools suite were designed to help and assist payment industry people in their day to day tasks and make their work the most effective. Our team would be grateful if you would suggest any improvements to our applications or report completely new functionality needed. Feedback from our users like this is exactly what drives the development of its and helps us to share our experience to wide public.
