Api products

XML (direct) model requires PCI DSS certification.

Direct XML 2.1/4.1

Cardlink VPOS is an application that is designed for processing merchant payments in ecommerce environment. The input to VPOS are payment requests originating at the merchant shopping solution. These requests are processed by VPOS and the output (transaction approved or declined) is sent back to the merchant shopping solution.

Cardlink VPOS can process payments in two methods. Direct XML or by Redirection to a specific page. This chapter describes the Direct XLM methodology and it should be noted that the PCI Compliance is a pre-requisite for this one. More information about PCI Compliance can be accessed here.

The payment methods that the merchant solution will use (credit, debit cards, Visa, Mastercard etc.) are decided by the merchant and provided that they are supported by Cardlink VPOS, they can be tested in this tool. Cardlink VPOS core design enables multiple types of merchant interfaces to be implemented.

Merchants can easily attach their look and feel to payment pages by supplying their own custom CSS stylesheet.

This document describes the newest versions (4.1 and 2.1) of interfaces based on RSA SHA256 signature security (4.1) and shared secret based SHA2-256 digest (2.1).


XML API Interface

The XML API interface plugin enables merchants using their own payment pages hosted in their system to directly access VPOS by using XML messaging.

XML Messaging is using request real time and response messages in the same request/response cycle. In request message merchant provides payment and order info and in response messages VPOS indicates the result of the action performed. By default the merchant should receive the response message within 30 seconds maximum.

Root element of request and response messages is VPOS

Current version of XML API is 4.1 and 2.1 that is copy of 4.1 only difference is that message security is in 2.1 ensured by a Digest element computed from canonicalized Message element appended with shared sercret.

The request message general structure:

<Message version=”4.1″messageId=”12345″timeStamp=”” lang=”en”>
<Authentication>… </Authentication>


The response message general structure:

<Message version=”4.1″ messageId=”12345″>

The general error message structure (returned in case request: message was unparseable or

<Message version=”1.0″ messageId=”12345″>

The exact xml bindings are defined in xsd schema.


Description of request and response message elements and fields and their usage:


Field/request  Type  Description
VPOS element XML root element
Message element type Message Message contents element
version attribute, xsi:string Message version default value “4.1” Required or 2.1
messageId attribute, xsi:ID Message unique identifier (values in request and reply messages this must match, also used for lookup signature reference object when validating signature) (“M1234567”)
lang attribute, xsi:string(2) Message attribute to specify context language (Optional)

(ISO 639-1 language code en, fi, sv, el, etc..)

timeStamp Attribute xsi:dateTime Approximate time when message was created (optiuonal for now but recommended)
Digest (v2.1 only) element xsi:string Required if version = 2.1.

The digest of message element if used instead of password to be calulated Base64(SHA2-256((utf8bytes(canonicalize(Message))+utf8bytes(sharedSecret))

Signature element ds:SignatureType Required if version = 4.1

The xml signature as defined




SignatureMethod Algorithm=http://www.w3.org/2001/04/xmldsig-more#rsa-sha256

Digest Method


Requests are signed by merchant private key and validated with merchant Certificate (merchant certificate generation is referred to section 5 page 30)











element Request Message element depending on request type
Authentication element Authentication element of request Message
Mid xsi:string (N1..30) Merchant number/identification in VPOS
OrderInfo   Orderinfo element of request Message
DeviceCategory xsi:string (1) Optional
OrderId xsi:string AN1..50 Merchant defined unique order id
OrderDesc xsi:string AN1..128 Order description defined by Merchant
OrderAmount xsi:decimal (max 9+3 or 10+2) Order amount (decimal number >0.0 and max 12 digits + decimal point)

amount is set to 0.0 for Tokenization without Authorization

Currency xsi:string A3 ISO4217 alphabetic currency code (USD, EUR)
PayerEmail xsi:string AN1..64 Order payer email address (string..64)
PayerPhone xsi:string N1..30 Order payer phone number, optional but strongly recommended (string..30)
AddFraudScore xsi:integer Incoming starting risk score (integer)
BlockScore xsi:integer Optional block score parameter that will be used to block the transaction if transaction riskScore reaches this value or above. (Postive Integer number)
Elements Var1.Var9

Var1, Var2, Var3,

Var4, Var5, Var6,

Var7, Var8, Var9

xsi:string AN1..1024 Free variable defined by merchant.
MOTO xsi:integer N1 Indicating whether it is a MOTO transaction (1

indicates MOTO)

Weight xsi:decimal Order shipping weight (kg) if item is shippable and shipping needs to be calculated by VPOS (decimal number >0) and it is supported
Dimensions xsi:string AN1..25 Order shipping dimensions (mm) in format width: height: depth for example a box 200:200:200 (string..25) can be used for shipping calculation if implemented so
BillingAddress element address Element of OrderInfo
country xsi:string AN2 Billing address country code (string 2 ISO 3166-1-alpha-2 code (US, FI, GB))
state xsi:string AN1..50 Billing address state (string.50)
zip xsi:string AN1..16 Billing address zip code (string..16)
city xsi:string AN1..64 Billing address city (string..64)
address xsi:string AN1..100 Billing address state (string 2 3166-2 country subdivision code). this value only applies to countries that have states (e.g USA)
ShippingAddress element:address Element of OrderInfo
country xsi:string AN2 Shipping address country code (string 2 ISO 3166-1-alpha-2 code (US, FI, GB)) Optional, required when  parameter weight or dimensions are present.
state xsi:string AN1..50 Shipping address state (string..50) Optional, required when  parameter weight or dimensions are present.
zip xsi:string AN1..16 Shipping address zip code (string..16) Optional, required when  parameter weight or dimensions are present. Optional, required when  parameter weight or dimensions are present.
city xsi:string AN1..64 Shipping address city (string..64) Optional, required when  parameter weight or dimensions are present.
address xsi:string AN1..100 Shipping address street (string..100) Optional, required when  parameter weight or dimensions are present.
PaymentInfo   Payment info element of request
PayMethod xsi:string AN1..20 valid values:

visa for VISA cards,

mastercard for MasterCard,

maestro for Maestro,

amex for American Express,

diners for Diners,

discover for Discover

CardPan xsi:string N11..19 Card number
CardExpDate xsi:string N4 Card expiration date in format YYMM
CardCvv2 xsi:string N3..4 CVV2/CVC2 security code from card.
CardHolderName xsi:string AN1..24 Card holder name
CardEncData Xsi:string ..2048 In case on merchant merchant site user browser RSA card data encryption is used  this field contains encrypted card data in form of Base64(RSA(UTF8Bytes(“pn={pan}&ey={exp year}&em={exp month}&c2={cvv2}&cn={cardholdername}”))

Values are urlencoded and with utf-8 char encoding (with javascript encodeURIComponent). This all is handled by server supplied component, merchant just need to forward value as returned to this field content.

If this field is present then fields CardPan, CardExpDate, CardHolderName, CardCvv2 must not be bresent

RecurringIndicator xsi:string AN1 Value “R” indicates recurring payment
RecurringParameters  element Recurring parameters element
ExtRecurringfrequency xsi:string N1..3 A value indicating the number of days between

the recurring payments. 28 is a special value

indicating a month.

ExtRecurringenddate xsi:string N8 Recurring end date Format yyyymmdd
InstallmentParameters element Installments parameters element
ExtInstallmentoffset xsi:integer N1..2 Defines the number of months between the entering of the transaction, n case installment payment
ExtInstallmentperiod xsi:integer N1..2 Defines the number of monthly payments in case installment payment. Valid value must be >1
ThreeDSecure element Element to support ThreeDSecure in XML api
EnrollmentStatus xsi:string AN1 In case of merchant is processing 3D secure prior to sending this xml message this field should contain 3D secure enrollment status (Y, N, U)
AuthenticationStatus xsi:string AN1 In case of merchant is processing 3D secure prior to sending this xml message this field should contain 3D secure authentication status (Y, N, U, A)
CAVV elem xsi:string AN28 In case of merchant is processing 3D secure prior to sending this xml message this field should contain 3D secure CAVV if authenticated. Base64 encoded value (28 chars) of CAVV  of value of 20 bytes
XID elem xsi:string AN28 In case of merchant is processing 3D secure prior to sending this xml message this field should contain 3D secure XID if authenticated. base64 encoded 28 char value of 20 byte XID
ECI elem xsi:string N2 In case of merchant is processing 3D secure prior to sending this xml message this field can optionally contain ECI value
Protocol elem xsi:string Required if not 3DS1, value from MPI responses

values 3DS1.0.2, 3DS2.1.0

Attribute elem AttributeType 0..n counts Extra attributes for 3DS2

add all attibutes with names








depending if available in MPI response.

Attribute named TDS2.dsTransID is currently required if successful 3DS2 authentication, others currently recommended.

ExtXOrderId xsi:string AN1..50 Optional merchant and acquirer agreed extension for recognizing returning customers with submitting previous successful order id of the merchant recognized customer. If functionality is not enabled for merchant this parameter is silently ignored. And if in such case CardPan is missing or is not valid error condition will be generated. Also used in original credit to locate original payment.
ExtTokenOptions Xsi:string N1 Optional for merchant and acquirer agreed token extension Value 1 if request tokenization and PAN is supplied.
ExtToken Xsi:string N12..19 Optional merchant and acquirer agreed token extension for recognizing payment tokens from previous successful payments.
TransactionInfo element Transaction info element (used in recurring cancel operation present in RecurringOperationRequest only)
OrderId xsi:string AN1..50 Merchant defined unique order id (of original payment)
TxId Xsi:long TxId  applicable in StatusRequest messsgae only
Operation xsi:string AN1..25 Predefined String value, Currently supported operation: Cancel (to cancel recurring occurring)
MasterPassInfo element A masterpass extension element if merchant inititated the xml api payment with MasterPass Wallet.
Attribute element, attr name=”status” Element value MasterPass session result status: success, cancel or error
Attribute element attr name=”txId” Element value Required if status was success, the masterpass tx id, from masterpass checkout data TransactionId
Attribute element attr name=”walletId” Element value Required if status was success, the masterpass wallet id, from masterpass checkout data walletID
Attribute  element attr name=”authMethod” Element value Required if status was success and masterpass returned authenticated options in chackout data
TxType element xsi:string Required for PaymentLinkRequest possible values can be PAYMENT_PREAUTH or PAYMENT
LinkValidityDays element xsi:int Optional for PaymentLinkRequest payment validity in days
MailLinkIfValidMail element xsi:boolean Optional for PaymentLinkRequest to request payment link mail to be sent by server if payerMail in OrderInfo was present
Responses/ Notification  
VPOS element XML root element
Message element type Message Message contents element
version attribute, xsi:string Message version default value “1.0” Required
messageId attribute, xsi:ID Message unique identifier (values in request and reply messages this must match, no other purpose)
lang attribute, xsi:string (2) Message attribute to specify context language (Optional)

(ISO 639-1 language code en, fi, sv, el, etc..)

timeStamp Attribute xsi:dateTime Message timestamp when approximate time of when message was created. Example 2015-04-30T12:21:02.402+03:00
Digest (v2.1 only) element xsi:string


The digest of message element if used instead of password to be calulated Base64(SHA2-256((utf8bytes(canonicalize(Message))+utf8bytes(sharedSecret))
Signature element ds:SignatureType The xml signature as defined https://www.w3.org/TR/xmldsig-core/



SignatureMethod Algorithm=http://www.w3.org/2001/04/xmldsig-more#rsa-sha256



Responses are signed by processor private key and validated with Processor certificate (processor certificate is referred to Section 6. page 31)

Response element Element of response type and named as

AuthorisationResponse, CaptureResponse, OriginalCreditResponse, RefundResponse, CancelResponse, RecurringOperationResponse

OrderId xsi:string Same value as in request message OnrderInfo
OrderAmount xsi:decimal Same value as in request message OnrderInfo
Currency xsi:string Same value as in request message OnrderInfo
PaymentTotal xsi:decimal Actual payment amount normally equals orderAmount or orderAmount + any fees if applicable.
Status xsi:string Transaction status in response or notficiation messages

AUTHORIZED, CAPTURED – payment was successful (accept order)

REFUSED – payment  failed, payment was denied for card or by bank (deny order)

REFUSEDRISK – payment  failed, payment was denied for card by risk score (deny order)

CANCELED – only in requrring operation response if supsequent requrrings are set to be canceled

ERROR – input, sysrtem or network error (deny order)

TxId Xsi:long Server supplied transaction id
Sequence Xsi:integer Used with recurrings
PaymentRef Xsi:string Remote payment reference like issue approval code.
RiskScore xsi:integer Optional risk score calculated by risk scroring subsystem if available
ExtToken Xsi:string Optional payment token if tokenization was requested and performed
ExtTokenPanEnd Xsi:string Optional payment token related PAN ending 4 numbers
ExtTokenExp Xsi:date Optional payment token expiration. (YYYY-MM-DDZ)

example 2018-02-01+02:00

ErrorCode Xsi:string Error code
Description Xsi:string Error or result description text
PaymentLink xsi:string element Payment Link URL
LinkMailed xsi:boolean element Indicator if payment link mail was sent to mail server.
Authentication element Authentication element of request Message
Mid xsi:string (N1..8) Merchant number/identification in VPOS
OrderId xsi:string Same value as in request message OnrderInfo
OrderAmount xsi:decimal Same value as in request message OnrderInfo
Currency xsi:string Same value as in request message OnrderInfo
PaymentTotal xsi:decimal Actual payment amount normally equals orderAmount or orderAmount + any fees if applicable.
Status xsi:string Transaction status in response or notficiation messages

AUTHORIZED, CAPTURED – payment was successful (accept order)

REFUSED – payment  failed, payment was denied for card or by bank (deny order)

CANCELED – only in requrring operation response if supsequent requrrings are set to be canceled

ERROR – input, sysrtem or network error (deny order)

TxId Xsi:long Server supplied transaction id of recurring master that started requiring sequence
Sequence Xsi:integer Recurring sequnece number
SeqTxId Xsi:long The recurring seequence transaction server supplied id
PaymentRef Xsi:string Remote payment reference like issue approval code.
ErrorCode Xsi:string Error code
Description Xsi:string Error or result description text
Attribute Complex element


StatusRequest   Query for transaction status
Authentication element Authentication element of request Message
Mid xsi:string Merchant number/identification in VPOS
TransactionInfo element
OrderId Element Xsi:string Use either order id or txid to query results if order id used then all transactions referenced are included such as captures, refunds associated
TxId Element Xsi:long Use txId to query by txId, only single transaction data is returned
StatusResponse   Response of transaction status containing one or many TransactionDetails
TransactionDetails element One or many
OrderId element
OrderAmount Element xs:decimal Merchant submitted order amount
Currency Element xs:string Order currency
PaymentTotal Element xs:decimal Final payment amount (order +/- adjustments, fees etc)
Status Element xs:string Payment status
TxId Element xs:long Transaction identifier
Sequence Element xs:integer In case of recurring
PaymentRef Element xs:string Payment reference or approval code if available
RiskScore Element xs:integer Risk score if available
ErrorCode Element xs:string Not used
Description Element xs:string Status description
Attribute Complex element


Many, rest of the transaction data. As

<Attribute name=”MERCHANT NO”>0000001</Attribute>

<Attribute name=”USER IP”></Attribute>

<Attribute name=”CHANNEL”>Redirection</Attribute>

<Attribute name=”3D STATUS”>1 – Fully authenticated</Attribute>

<Attribute name=”SETTLEMENT STATUS”>NA</Attribute>

<Attribute name=”BATCH NO”>28</Attribute>

<Attribute name=”ISO response code”>15</Attribute>

<Attribute name=”ORDER DESCRIPTION” />

<Attribute name=”CARD MASK PAN”>4016#####0002</Attribute>

<Attribute name=”ECOM-FLG”>5</Attribute>

<Attribute name=”ECI”>05</Attribute>

<Attribute name=”PAYEREMAIL”>demo@cardlink.gr</Attribute>

<Attribute name=”PAYERPHONE”>+372 123 1234</Attribute>

<Attribute name=”BILLCOUNTRY”>FI</Attribute>

<Attribute name=”BILLZIP”>76543</Attribute>

<Attribute name=”BILLADDRESS”>Billto tn 6-9</Attribute>

<Attribute name=”SHIPCOUNTRY”>FI</Attribute>

<Attribute name=”SHIPSTATE”>Harjumaa</Attribute>

<Attribute name=”SHIPZIP”>12345</Attribute>

<Attribute name=”SHIPADDRESS”>Viru tn 6-9</Attribute>

<Attribute name=”EXTACQUIRERID”>026</Attribute>

TxType Element xs:string Transaction type
TxDate Element xs:dateTime Transaction execution timestamp
TxStarted Element xs:dateTime Transaction started timestamp
TxCompleted Element xs:dateTime Transaction completed timestamp
PaymentMethod Element xs:string Payment method used.
ErrorMessage element Response type of ErroMessage, normally given if request message validation failed or system error.
ErrorCode Xsi:string Error code
Description Xsi:string Error description text
OriginalXML Xsi:string Encoded original XML received in case the error was in XML parsed
Field element/


Sale/ AuthorizationRequest TokenizationRequest CaptureRequest OriginalCreditRequest RefundRequest CancelRequest RecurringOperationRequest SaleResponse AuthorisationResponse CaptureResponse OriginalCreditResponse RefundResponse CancelResponse RecurringOperationResponse RecurringNotification  




version R R R R R R R R R R R R R R R R R 4.1 or 2.1
messageId R R R R R R R R R R R R R R R R R Unique value of numbers and or chars xsi:ID and matching in request, response messages. max length 128
lang O O O O O O O O O O O O O O O O Optional iso language code as el, en, ru, fi, et, sv. This is used to set context language in case emails or any other type actions are triggered with this request.
timeStamp R R R R R R R R R R R R R R R R R Required
Mid R R R R R R R R R
OrderInfo R R R R R R
      OrderId R R R R R R
      OrderDesc O O O
      OrderAmount R R R R R R
      Currency R R R R R R
      PayerEmail O O
      PayerPhone O O
      AddFraudScore O O
      BlockScore O O
      Var1 O O O
      Var2 O O O
      Var3 O O O
      Var4 O O O
      Var5 O O O
      Var6 O O O
      Var7 O O O
      Var8 O O O
      Var9 O O O
      MOTO O O
      Weight O O
      Dimensions O O
      BillingAddress O O Billing address element and sub elements
      ShippingAddress O optional shipping address element and sub element
PaymentInfo R O1 O1 O1 O
      PayMethod R3 O1 O1 O1
      CardPan R2 O1 O1 O1 Not present if CardEncData present.
      CardExpDate R Not present if CardEncData present.
       CardCvv2 O Required if not MOTO and required for card type/brand,

Not present if CardEncData present.

        CardHolderName C Optional but highly recommended.

Not present if CardEncData present.

         CardEncData C Used if RSA card encryption then CardPan, CardExpDate, CardHolderName and CardCcc2  shal not be present
         RecurringIndicator C Required for recurring payment
         RecurringParameters C Required for recurring payment
           ExtRecurringfrequency C Required for recurring payment
           ExtRecurringenddate C Required for recurring payment
         InstallmentParameters C Required for installment payment
           ExtInstallmentoffset C Required for installment payment
           ExtInstallmentperiod C Required for installment payment
         ThreeDSecure C Required for 3D transactions
           EnrollmentStatus C Required for 3D transactions
           AuthenticationStatus C Required for 3D transactions
           CAVV C Required for 3D transactions
           XID C Required for 3D transactions
           ECI C Required for 3D transactions
           Protocol C Required for 3DSv2 transactions
           Attribute C     TDS2.dsTransID attribute is required for 3DSv2 transactions
         ExtXOrderId O2 R O2 – may be present instead of CardPan. Required for original credit to lookup source payment.
         ExtTokenOptions O
         ExtToken O
TransactionInfo R
         OrderId R
Operation R
Signature  R R R R R R R R R R R R R R R R Required for all (v4.1)
Digest R R R R R R R R R R R R R R R R Required for all (v2.1)
Card R CardInfo
Token TokenInfo
LinkValidityDays O Optional days payment link is valid, defaults to merchant or system value
MailLinkIfValidMail O xsi:boolean true/false indicates if service will email link to payer if payeremail in OrderInfo
     OderId R R R R R R R R R Order Id supplied by merchant originally
     OrderAmount R R R R R R R R
     PaymentTotal R R R R R R R R
     Currency R R R R R R R R
     Status R R R R R R R R R Status
     TxId C C C C C C R R In case of transaction processing has started (no rejection due invalid input request), In case of recurring Notificatuion this is master recurring transaction id
     Sequence R Sequence of recurring in notification
     SeqTxId R The executed recurring sequence transaction id
     PaymentRef C C C C C C C Payment reference such as approval code if available
     RiskScore O O Optional risk score calculated by risk scoring subsystem if available
     ExtToken O O
     ExtTokenPanEnd O O
     ExtTokenExp O O
     ErrorCode C C C C C C C C C Error code in case of Status=ERROR
     Description O O O O O O O O O Optional error description
     Attribute O O O O O O O O Optional attributes, may be custom per implementation.
     OriginalXML In general error message only to copy back the error as content received for merchant debugging.
     PaymentLink R present if no error
     LinkMailed R R=present if no error
Signature  R R R R R R R R Required for all (v4.1)
Digest R R R R R R R R R R R R R R Required for all (v2.1)


Field element/


StatusRequest TokenizationRequest StatusResponse TokenizationResponse Description
Mid R R
         TransactionInfo R
OrderId C Either OrderId or TxId is required
TxId C Either OrderId or TxId is required
StatusResponse R
    TransactionDatails R
OrderId R
OrderAmount R
Currency R
PaymentTotal R
Status R
TxId R
Sequence O
PaymentRef O
RiskScore O
Description O
Attribute O List of attributes depending on what information is available.

Attribute name can be one of the following:

MERCHANT NO – merchant number,

REFUNDED AMOUNT – amount refunded if availble,

USER IP – use ip if available,

CHANNEL – channle originated

3D STATUS – status

CAPTURED AMOUNT – captured amt

SETTLEMENT FILE – settl file name

BATCH NO – batch number

ISO response code – iso response if available

ExtData – additional data from external payment systems if available


CARD MASK PAN – masked pan 5+3 or 4+4 or 6+2







ECOM-FLG – ecom flag in auth message,

ECI – eci from mpi,

























* – Only possible if with special bonus loyalty extension.

** – Only possible if with returning customer extesnion.

TxType R
TxDate R Transaction exec date
TxStarted R Transaction started
TxCompleted O May bemissing if transaction did not complete due errors.
PaymentMethod O


R R CardInfo type ref required, if CSE then encData reuired else pan,exp reuired
    Attribute:ref R unique number request id within merchant scope
    Attribute: pan C Card pan (required if plain, no encData)
    Attribute: exp C Card expiry date (required if plain, no encData, xsd:date (YYYY-MM-DD))
    Attribute: chn C Cardholder name (required if plain, no encData)
    Attribute: encData C CSE (required if encoded card data)
            Token R  Token Information element (one or more) included in TokenizationResponse
     Attribute: ref R unique number request id within merchant scope used only in return file to match request
     Attribute: status R Status of tokenization (OK if no errors occured)
  Attribute: tokenValue O Value of token
  Attribute: panEnd O Last 4 digits of pan
  Attribute: exp O Expiration Date


R R R id attribute of request/response matching
           statusMessage O Optional status description

O1  - if supported feature then fields may not need to be present if not supported then the fields are required. Availability of this option shall confirm with system administrator (Your customer support). If values not sent, then whole PaymentInfo element shall be excluded from message.

R2 and O2 - If system supports and merchant is set tp participate in returning customer recognition extension then if merchant already has a successful order with a card with this customer and the card is still valid and customer chooses to make this next order with same card and the days and amounts between orders are in certain limits then merchant may send ExtXOrderId instead of CardPan. In such case if validations are passed system automatically uses pan from previous specified order. Recommended maximum period between previous order and next returning customer extension order could be 6 months (180 days).


Currently supported operations: 

AuthorisationRequest-make a pre-authorization

CaptureRequest- capture a pre-authorization

RefundRequest- make refund

SaleRequest- make a payment

CancelRequest- make reversal for an unsettled transaction

RecurringOperationRequest- with operation Cancel, cancel recurring master scheduling

RecurringNotification – Optional message posted to merchant if a recurring child is executed on server, merchant does not need to send response XML to this on accept merchant server should respond with http status code 200/OK or in case merchant does not recognize the transaction 406/Not Acceptable or 400/Bad Request if the message format is invalid. Server just acknowledges the response code and performs no additional actions based on merchant response code.

StatusRequest- query transaction status

TokenizationRequest- tokenize a card to token

PaymentLinkRequest- Generate a one time payment link


Error code values:

Filled in case status is ERROR  with following values

M1 – Invalid merchant id

M2 – Authentication failed (wrong password or digest or signature)

SE – System error (message contains error id, system or configuration error to be investigated)

XE – Invalid XML request not parseable or does not validate

I0 – Invalid or unsupported request

I1 – Message contains invalid data item or missing required item

I2 – Message contains invalid installment parameters

I3 – Message contains invalid recurring parameters

I4 – Message contains invalid or mismatching card data

I5 – Message contains invalid expiration date card data

I6 – Selected payment method does is not supported or not matching the payment card

O1 – Operation is not allowed because logic is violated or wrong amounts

O2 – Original transaction is not found to perform operation.

May be also filled in case of status is REFUSED with acquirer network supplied ISO response code

Digest calculation with XML API: 2.1 https://developer.cardlink.gr/documentation_categories/integration/#Digest-calculation-with-XML-API-2.1

Signature calculation with XML API V4.1: https://developer.cardlink.gr/documentation_categories/integration/#Signature-calculation-with-XML-API-V4.1


Examples how to generate merchant keys 

With openssl

It’s just possible to do all in one line:

openssl req -x509 -newkey rsa:2048 -sha256 -keyout merchantkey.pem -out merchantcert.pem -days 1460 -subj “/C=EE/ST=My State/L=my City/O=Company Name/OU=7711223/CN=www.mysite.com”

The output file merchantcert.pem need to be sent to service provider to install with Your merchant account so Your messages will be validated with public key in Your certificate.

C – is two letter country code

L – locality eg. city where you are located.

OU – is recommended to fill with Your merchant number with service provider.

O – shall be your company full or public name.

CN – is recommended (not required as with server certificates) to be your website name

rsa:keysize is recommended to be 2048 or 3072 bits for foreseeable future and validity days up to 1460 days (4 years), ask service provider if it has specific policy or requirements.

Use necessary measures to protect your private key in generated file merchantkey.pem.

Converting private key to PKCS8 format handleable by  java:

openssl pkcs8 -topk8 -in merchantkey.pem -inform PEM -outform PEM -out merchantkey-p8.pem -nocrypt

With java keytool

With java keytool private key remains in keystore and cannot be extracted unless special software is used. So Your software shall operate directly with this keystore then.

keytool -genkey -keyalg RSA -sigalg SHA256withRSA -dname ”CN=www.mysite.com,OU=7711223,O=Company Name,L=my City,S=My State,C=EE” -keysize 2048 -validity 1460 -alias mykey2017  -storetype JCEKS -keystore mykeystore.jceks -keypass strongPassKey -keystore mycerts.jceks -storepass strongPass

Now export Your certificate to a file that can be sent to service provider:

keytool -exportcert -alias mykey2017 -file merchantcert.pem.cer -storetype JCEKS -keystore mycerts.jceks -storepass strongPass -rfc


Processor Certificate

Processor certificate is used by merchant to calculate the signature value for the response messages.

For testing purposes, merchant can use the following processor certificate:























For production, please contact via email at ecommerce_support@cardlink.gr