2014
Content
1. Introduction...............................................................................................................................................4
1.1. What is SCI? ........................................................................................................................................4
1.2. Description of the present document ................................................................................................4
1.3. Consumer audience............................................................................................................................4
1.4. Terminology ........................................................................................................................................4
1.5. Abbreviations .....................................................................................................................................5
2. Description ................................................................................................................................................5
2.1. Main information ...............................................................................................................................5
2.2. Signing up ...........................................................................................................................................5
2.3. Interaction ..........................................................................................................................................5
2.4. Sceme of work ....................................................................................................................................6
2.5. Example of payment process .............................................................................................................8
3. Protocol .....................................................................................................................................................9
3.1. Checkout settings ...............................................................................................................................9
3.2. Form of payment request.................................................................................................................11
3.3. Client result page..............................................................................................................................14
3.4. Notification of payment ...................................................................................................................15
3.4.1. Checking information of payment .............................................................................................16
3.5. Digital signature forming ..................................................................................................................17
4. Advanced features ...................................................................................................................................17
4.1. Hidden SCI mode ..............................................................................................................................17
4.1.1. Description ................................................................................................................................17
4.1.2. Receiving of available for checkout list of payways...................................................................17
4.1.3. Data receiving on the cost of payment on the payment gateway.............................................18
4.1.4. Receiving data on payment form of payment gateway .............................................................19
5. Testing .....................................................................................................................................................20
5.1. Creation of payment request form...................................................................................................20
5.2. Payment process and carrying out of payment................................................................................20
6. Reference book........................................................................................................................................21
6.1. Currency codes .................................................................................................................................21
6.2. Error codes .......................................................................................................................................21
6.3. Payway codes ...................................................................................................................................22
7. Notes .......................................................................................................................................................24
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8. Links .........................................................................................................................................................24
9. Lisy of changes.........................................................................................................................................25
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1. Introduction
1.1. What is SCI?
SCI (Shop Cart Interface) – the program interface, which allows every merchant automatically receive
payments online.
Demonstration - https://sci.interkassa.com/demo/.
1.2. Description of present document
In the given document presented exhaustive information of interaction protocol with SCI payment
gateway. Also, you`ll find typical decisions, examples of realization and all necessary information for
integration of your site with the gateway.
1.3. Consumer audience
Present document is intended for technical specialists, web-masters and developers, working for the
company that is willing to receive and process data of payments in the Internet.
For using given protocol it is necessary to have base knowledge of web-developer. Protocol is presenting
different by complication typical sign-up decisions.
1.4. Terminology




SCI (Shop Cart Interface) – program interface, which allows every merchant automatically
receive payments online.
Merchant – account owner, who receives on its account payments via SCI, as the rule, goods or
services that are presented on his or her web-shop.
Client – purchaser, who buy goods or services from merchant. The buyer is redirected onto SCI
for making payment.
Checkout – point of receiving payments on merchant site.
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1.5. Abbreviations







IK — Interkassa
SCI — ShopCartInterface
CO — Checkout - point of receiving payments on merchant site.
XSS — СrossSiteSсriрting
EDS — Electronic digital signature
URL — Uniform Resource Locator
WWW — World Wide Web
2. Description
2.1. Main information
SCI – program interface for receiving payments via Internet. The main point of payment acceptance
gateway reduces to single entry point of client paying and returning back onto the site after paying. It
allows, independently of payway, uniformly interact with client and process payments. As any program
interface, it has its own interaction protocol, its functionality, number of demands and restrictions.
Depending on the degree of integration, protocol allows very flexible realization of various schemes of
interaction between you and your client.
2.2. Connection
All you need for accepting payments online is to:
1.
2.
3.
4.
Register in Interkassa system.
Create new (or use current) business-account.
Create new checkout and adjust it (setting parameters are given below).
Redirect client for payment with HTML-form of payment inquiry.
2.3. Interaction
From the point of integration view, SCI is the web-page (https://sci.interkassa.com/) that receives HTTP
request with GET or POST parameters, and depending on the type of action (ik_act) and interface
(ik_int: web / json) answers with corresponding result.
Inasmuch as the service gives opportunity of flexible integration, beneath we offer typical solutions for
various tasks and complexity of fulfillment.
Depending on the type of your business, SCI can be used by different ways:

If you haven`t own site and sell in small amount goods or services and orders are processed by
hands, it’s enough to redirect client for paying with HTML-form that can be placed as in e-mail,
so on your site. After payment realization it will be available in your personal cabinet. Also, you
can receive e-mail or SMS notification after payment enrollment.

If you provide goods or services having your own billing and you are willing automatically
process received payments, you need to realize logic of processing notification from SCI about
completed payment. It will be transmitted automatically after funds crediting onto your site,
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independently of payment, which can be Visa, MasterCard or Wire transfer, terminals of self
care etc.

If you want to realize choosing of payway and redirecting of client directly on the payment
gateway bypassing SCI web-interface, this can be done due to protocol support of JSON
interface, which allows your site to receive all necessary data for processing in hidden mode for
client.
2.4. Scheme of work
Checkout Page — page, on which HTML-form of payment request is displayed (SCI Form).
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Paysystems List — page with available for present checkout payment systems, with assist of which client
can done the payment. Example:
Payway List — page of payway choosing. Example:
Create Invoice — script of creating invoice and redirecting client on the payment gateway (Pay Form).
Payment Gateway — payment gateway with assist of which client makes payment.
Payment Processing — script for carrying out a payment on the payment gateway. When carrying out
the payment, SCI server (Interaction page) informs of the result of processing. In its turn, SCI notifies
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Interaction Page on the merchant server with the information about the invoice and payment processing
(Interaction Form).
Payment Result Page — result page of payment processing from that client redirects on the SCI.
Result Page — SCI page, on that client is redirected after payment, waiting for SCI result notification of
the payment processing by payment gateway, dependently on that accordingly on the Success Page if
success payment processing, Fail Page if unsuccessful payment or incomplete payment process onto
Pending Page. Example:
2.5. Example of payment process
Let’s look at the typical process of payment on the example of internet-shop. Assume that, internet-shop
offers to client an opportunity of purchase ticket to cinema. Payment of the order need to be processed
automatically and the ticket is provided to client immediately after payment.
1. Client chooses already liked showing and seats. Forms an invoice. Identification number and
sum of payment are given for the created order.
2. Client jumps on the page of payment (Checkout page) on the merchant site and he or she is
shown the button for redirection on the SCI payment gateway. The button is linked with the
HTML-form (SCI Form) and indicates the SCI web-interface – https://sci.interkassa.com/ . This
HTML-form includes number of hidden parameters for SCI (view Protocol); also it includes data
of the payment (sum, order ID and others).
3. When pressing the button client is redirected onto the SCI web-interface with available
payment systems (Paysystems List) with that payment can be done.
4. On the page of paysystems choosing (Paysystems List) client is shown data of payment, sum
and description.
5. While choosing one of the paysystems client is shown all the methods of payment through it
(Payway List). Also, client is suggested with the terms of payment and mentioning of his or her
contacts.
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6. When pressing the button “Buy” new invoice is created in Interkassa system (Create Invoice)
that is fixed by the checkout and client is redirected (Pay Form) onto the payment gateway
(Payment Gateway).
7. On the Payment Gateway client makes the payment.
8. While processing the payment (Payment Processing) SCI receives notification about the result
of payment processing and retranslates it in unified format (Interaction Form) on the site of
merchant (Interaction Page).
9. Payment gateway redirects the client onto the page of result (Result Page) after the payment.
On this page, SCI based on the available data, determines the status of the payment and
dependently on it redirects the client on the suitable page of the merchant site (Success Page,
Fail Page, Pending Page).
3. Protocol
3.1. Checkout settings
SCI settings begin with checkout settings. They allow set the values by default, logic of gateway work and
web-interface, security settings, available payways and others. The full list of checkout properties is
shown below:
Property
Name
Note
Name
Name
It is displayed on the SCI.
Url
URL
It is displayed on the SCI.
Desc
Description
It is displayed on the SCI.
Fee Rate
Commission of Interkassa
SCI is used when payment amount calculating. See tariffs.
FeeShift
Shifting the fee onto buyer
SCI is used when payment amount calculating. Shows in
percentage the part of fee that was laid onto seller. For
example: if set 30% of fee on the seller, than 70% on the
buyer. On the basis that, Interkassa fee is 3% and, For
example, payment sum is 100 c.u., than payment amount in
the payment system makes up to 102.1 c.u. and taken funds
for crediting to checkout account are 99.1 c.u.
PaymentNoUniqu
e
Checking of the unique payments
number
SCI is used. Such option allows carrying out the checking
before creating new payment on its unique by the number. In
case, if the same number of the payment was found in
Interkassa billing than corresponding error message is issued.
When checking SCI parameter is used "Ошибка! Источник
ссылки не найден. source not found". Disabled by default.
Payment Amount
Edit
Payment amount edit
If turned on, than allows client by himself to specify the
amount of payment on SCI. Disabled by default.
PaymentAmountE
ditOverride
Opportunity to override the
feature of payment amount edit
Specify the opportunity for overriding the feature of
“Payment amount edit” by the parameter "ik_am_ed" on
SCI. Disabled by default.
MAIN
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Payment Lifetime
Lifetime of payment
Specify in seconds expiry time of the payment after its
creation. Does not used if the option of payment lifetime is
set by the parameter "ik_exp" on SCI. By default it is
"2592000".
PaymentLifetime
Override
Opportunity to override the
payment lifetime
Specify the opportunity for overriding the “Payment lifetime”
by the parameter "ik_ltm" on SCI. Disabled by default.
ShowLogo
Logo displaying
Specify the opportunity for displaying checkout logo onto SCI
web-interface. Disabled by default.
SignAlgorithm
Algorithm of digital signature
forming
SCI is used when digital signature forming. Available
algorithms: md5, sha256, rsa. It is "md5” by default.
SignKey
Key of digital signature
SCI is used when digital signature forming.
SignTestKey
Key of digital signature for testing
SCI is used when digital signature forming, if the payment
SECURITY
was done via test payment system. See testing.
SignCoRequired
If digital signature from the checkout
is required
SCI is used when checking the incoming parameters from the
checkout, if the option is activated. Disabled by default. See
digital signature forming.
INTERACTION
Success Url
URL page of success payment
SuccessUrlOverrid Opportunity to override URL page
of success payment
e
Is used when redirecting client from SCI back to checkout
page, if payment was done successfully.
Specify the opportunity for overriding the feature “URL page
of success payment” by the parameter “ik_suc_u” on SCI.
Enabled by default.
SuccessMethod
Method of page requirement of
success payment
Is used when redirecting client from SCI back to checkout
page, if payment was done successfully. It is POST by default.
Success Method
Override
Opportunity to override method
of page requirement of success
payment
Specify the opportunity for overriding the feature “Method
Fail Url
URL page of fail payment
Is used when redirecting client from SCI back to checkout
page, if payment was failed.
Fail Url Override
Opportunity to override URL page
of fail payment
Specify the opportunity for overriding the feature "Method
of page requirement of success payment” by the
parameter "ik_suc_m" on SCI. Enabled by default.
of page requirement of fail payment" by the parameter
"ik_fal_u" on SCI. Enabled by default.
Fail Method
Method of page requirement of
fail payment
Is used when redirecting client from SCI back to checkout
page, if payment was failed. It is POST by default.
Fail
MethodOverride
Opportunity to override method
of page request of fail payment
Specify the opportunity for overriding the feature "Method
of page request of fail payment" by the parameter "ik_fal_m"
on SCI. Enabled by default.
Pending Url
Pending URL page of payment
processing
Is used when redirecting client from SCI back to checkout
page, if payment is in process.
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Pending Url
Override
Opportunity to override pending
URL page of processing payment
Specify the opportunity for overriding the feature "Pending
URL page of payment processing" by the parameter
"ik_pnd_u" on SCI. Enabled by default.
Pending Method
Method of pending page request
of payment processing
Is used when redirecting client from SCI back to checkout
page, if payment is in process. It is POST by default.
Pending Method
Override
Opportunity to override method
of method of pending page
request of payment processing
Specify the opportunity for overriding the feature "Method
Interaction Url
Interaction URL page
SCI is used when sending notification about the status of
payment on the site of checkout. See notification of payment
status.
Interaction Url
Override
Opportunity to override
Interaction URL page
Specify the opportunity for overriding the feature
"Interaction URL page" by the parameter "ik_ia_u" on SCI.
Disabled by default.
Interaction
Method
Method of interaction page
request
SCI is used when sending notification about the status of
payment on the site of checkout. It is POST by default.
Interaction
Method Override
Opportunity to override method
of interaction page request
Specify the opportunity for overriding the feature "Method
of interaction page request" by the parameter "ik_ia_m" on
SCI. Disabled by default.
Interaction
Confirm Http
Code
Http-code of confirmation about
successful receiving of the
payment notification
SCI is used when sending notification about the status of
payment on the site of checkout. If while sending
notification, answer of HTTP-code from server of the
checkout won`t be the same as the specified value, then
such notification wouldn`t be consider as delivered and will
be resent again. It is "200" (OK) by default.
Interaction
Confirm Text
Confirmation text of successful
receiving of notification about the
status of payment
SCI is used when sending notification about the status of
payment on the site of checkout. If while sending
notification, in the body of answer from the server of
checkout will be mention text, then such notification
wouldn`t be consider as delivered and will be resent again.
Disabled by default.
of pending page request of payment processing” by the
parameter "ik_pnd_m" на SCI. Enabled by default.
3.2. Form of payment request
Present HTML-form (SCIForm) is key issue in the SCI protocol. With its assist, you can redirect client to
the payment form from every point of your web-application. You send all necessary values in it, such as
checkout identifier, amount and currency of payment, also are sent links of your site on that a client will
be redirected after success or fail payment, for example:
<form name="payment"
<input type="hidden"
<input type="hidden"
<input type="hidden"
<input type="hidden"
<input type="submit"
</form>
method="post" action="https://sci.interkassa.com/"accept-charset="UTF-8">
name="ik_co_id" value="51237daa8f2a2d8413000000" />
name="ik_pm_no" value="ID_4233" />
name="ik_am" value="1.44" />
name="ik_desc" value="Payment Description" />
value="Pay">
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Also, payment form can consist of additional values, which influence onto the available payways, expiry
time of the order, language of merchant interface etc. Full list of the values of payment form are given
below:
Key
Name
Format
Example
Description
ik_co_id*
CheckoutID
/^[\w\-]{1,36}$/D
4f269503a1da9
2c807000002
Checkout identifier. Obligatory parameter. See checkout
settings.
ik_pm_no
Payment No.
/^[\w\-]{1,32}$/D
14533;
ID_4233
Payment number. Is saved in Interkassa billing. Allows
identify payment in the system, also to connect orders in
your billing. If the given option set, then unique is
checking. Optional parameter.
ik_cur
Currency
/^.{3}$/
USD; EUR; UAH
Payment currency. Obligatory parameter, if checkout has
more than one currency. See checkout settings.
ik_am *
Amount
/^[\d]{1,15}([\.,][\d]
{1,4})?$/
1.43; 43
Payment amount. Obligatory parameter.
ik_am_ed
Amount Edit
/0|1/
0; 1
Editing of the amount of the payment. If turned on, allows
client to put in payment amount individually. Optional
parameter. It is used feature of checkout “Payment amount
edit” by default.
ik_am_t
Amount Type
/invoice|payway/
invoice; payway
ik_desc
Description
/^.{0,255}$/
Payment
Description;
Cool stuff
Payment description. Optional parameter.
ik_exp
Expired
/^.{0,30}$/
2011-05-01;
2011-10-01
20:50:33
Expiry period of payment. Doesn`t allow client to pay for
the mentioned order after expired period. If the payment
was done after it, then funds are credited onto his personal
account in Interkassa system. Parameter is used if the
payment connected with order and loses its unique quickly
after expiry period. For example: online booking. Optional
parameter.
ik_ltm
Lifetime
/^[\d]{1,10}$/
3600; 86400
Payment lifetime. Specify in seconds period of payment life
after its creation. It doesn`t use if payment expiry period is
set (ik_exp). Optional parameter. Checkout feature
“Payment lifetime” is used by default.
ik_pw_on
Payway On
/^[\w;,\.]{0,512}$/
webmoney;
w1_merchant_
usd
Turned on payways. Allows specify available payways for
client. Optional parameter.
ik_pw_off
Payway Off
/^[\w;,\.]{0,512}$/
webmoney_me
rchant
Turned off payways. Allows specify disabled payways for
client. Optional parameter.
ik_pw_via
Payway Via
/^[\w]{0,62}$/
visa_liqpay_mer
Elected payway. Allows specify exact payway for client.
Parameter works only with acting value (ik_act) that is set
Payment
Amount type of payment. Allows specify the strategy of
calculating the amount payment of checkout and
paysystem. Dependently on it, calculates those or that
amount. If “invoice” amount type is mentioned than
amount payment is calculated from the checkout amount
type. If specified "payway" amount type – than conversely.
It is "invoice" by default.
Payway
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chant_usd
in "process" or "payway". See action (ik_act).Optional
parameter.
System
ik_sign
Signature
/^.{0,128}$/
oVAOevI3mWrc
vrjB4j/ySg==
Digital signature. See digital signature forming. Obligatory
parameter, if in the checkout settings value “If digital
signature from the checkout is required” is set. (Sign Co
Required).
ik_loc
Locale
/^.{5}$/'
ru; de_us
Locale. Allows evidently specify language and region set for
the client. Form by the template: [language [_territory].
Defines automatically by default.
ik_enc
Encoding
/^.{0,16}$/
utf-8; ISO-88591; cp1251
Encoding. It is used UTF-8 encoding by default.
ik_usr
User
/^.{0,64}$/
usermail@gmail
.com;
+380501234567
User contact information. Assume the value as email or
phone number. Optional parameter.
ik_ia_u
Interaction
Url
URL
http://www.site
.com/interactio
n.script
URL interaction page. Optional parameter.
ik_ia_m
Interaction
Method
/get|post/i
POST, GET
Method of interaction page request. Optional parameter.
ik_suc_u
Success Url
URL
http://www.site
.com/success.sc
ript
URL page of success payment. Optional parameter.
ik_suc_m
Success
Method
/get|post/i
POST, GET
Method of success payment page request. Optional
parameter.
ik_pnd_u
Pending Url
URL
http://www.site
.com/pending.s
cript
URL pending page request of payment processing. Optional
parameter.
ik_pnd_m
Pending
Method
/get|post/i
POST, GET
Method of pending page request of payment processing.
Optional parameter.
ik_fal_u
Fail Url
URL
http://www.site
.com/fail.script
URL page of fail payment. Optional parameter.
ik_fal_m
Fail Method
/get|post/i
POST, GET
Method of fail page request. Optional parameter.
Action
/process|payways|
payways_calc|payw
ay/
process;
payways
Action. Allows overriding initial status of payment process.
Optional parameter.
Interaction
Protocol
ik_act
process — handle process;
payways — payment method;
payways_calc — calculation of payment ways;
payway — payment direction.
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ik_int
Interface
ik_x_[nam
e]
X Prefix
/web|json/
web; json
Interface. Allows specify format of interface of SCI as "web"
or "json". It is "web" by default.
ik_x_field1 =
somedata;
ik_x_baggage1
= code123;
Prefix of additional fields. Allows transmitting of additional
fields on SCI, after which these parameters are included in
notification about success payment onto the interaction
page.
For creation you can use our generator of payment form.
3.3. Client result page
Payment gateway redirects client on the result page after payment (Result Page). On this page SCI tries
to determine on the basis of available data the status of the payment and dependently on this redirect
client on the proper result page of seller (Success Page, Fail Page, Pending Page) accordingly. Also, in the
return form of client on the checkout (Return Form), SCI can send additional parameters depending on
the checkout setting and parameters of the payment. Full list of the return form parameters are given
below:
Key
Name
Example
Description
ik_co_id
CheckoutID
4f269503a1da92c807000002
Checkout identifier. See checkout settings.
ik_pm_no
Payment No.
14533; ID_4233
Payment number. Saved in Interkassa billing. Allows
identify payment in the system and connect it with the
order in your billing. Unique is checking if in the
checkout settings such option is set.
ik_cur
Currency
USD; EUR; UAH
Payment currency.
ik_am
Amount
1.43; 43
Payment amount.
ik_desc
Description
Payment Description; Cool
stuff
Payment description.
ik_pw_via
Payway Via
visa_liqpay_merchant_usd
Chosen payway.
ik_x_[name]
X Prefix
ik_x_field1 = somedata;
ik_x_baggage1 = code123;
Prefix of additional fields.
ik_inv_crt
Invoice Created
2013-03-17 17:30:33
Time of payment creation.
ik_inv_prc
Invoice Processed
2013-03-20 15:46:58
Time of payment invoice processing.
ik_inv_st
Invoice State
success; fail
Payment invoice status. Possible values:
Main
Additional
new — new, waitAccept —wait for payment, process —
is in process, success —success payment, canceled—
cancelled payment, fail—fail payment.
ik_ps_price
Paysystem Price
25.32
Amount of payment in paysystem.
ik_co_rfn
CheckoutRefund
24.94
Amount for refund on the checkout balance.
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Attention! Inasmuch as the clients return form (Return Form) is redirected via unsecured
channel therefore it can`t be used for crediting of payment by your web-application. You need to
use interaction form of payment for this (InteractionForm).
3.4. Notification of payment
While carrying out the payment, SCI creates request with the data over it on the interaction page
(InteractionURL). This request consists of all necessary data for the completing payment process of the
order on your site.
The given form is intended for tight integration of your site with SCI. It allows automate the process that
is initialized by receiving such notification about success payment, for refunding the payment and order
processed in the billing on your site.
Full list of result page form is given below:
Key
Name
Example
Description
ik_co_id
CheckoutID
4f269503a1da92c807000002
Checkout identifier. Obligatory parameter.
See checkout settings.
ik_pm_no
Payment
No.
14533; ID_4233
Payment number. Saved in Interkassa
billing. Allows identify payment in the
system and connect it with the order in
your billing. Unique is checking if in the
checkout settings such option is set
Optional parameter.
ik_desc
Description
Payment Description; Cool stuff
Payment description. Optional parameter.
ik_pw_via
Payway Via
visa_liqpay_merchant_usd
Chosen payway. Allows specify exact
payway for client. Parameter works only
with acting value (ik_act) that is set in
"process" or "payway". See action
(ik_act).Optional parameter.
ik_am
Amount
1.43; 43
Payment amount. Obligatory parameter.
ik_cur
Currency
USD; EUR; UAH
Payment currency. Obligatory parameter, if
checkout has more than one currency. See
checkout settings.
ik_x_[name]
X Prefix
ik_x_field1 = somedata; ik_x_baggage1 =
code123;
Prefix of additional fields. Allows
transmitting of additional fields on SCI,
after which these parameters are included
in notification about success payment onto
the interaction page.
ik_inv_id
Invoice Id
12345; 5632156
Invoice identifier.
ik_co_prs_id
Checkout
Purse Id
307447812424
Checkout purse identifier.
Main
Additional
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ik_trn_id
Transaction
Id
14533; ID_4233
Transaction identifier.
ik_inv_crt
Invoice
Created
2013-03-17 17:35:33
Time of invoice creation.
ik_inv_prc
Invoice
Processed
2013-03-17 17:36:13
Processing time.
ik_inv_st
Invoice
State
success; fail
Payment status.
ik_ps_price
Paysystem
Price
25.00
Payment amount in paysystem.
ik_co_rfn
CheckoutRe
fund
24.94
Amount for refund onto checkout.
ik_sign
Signature
oVAOevI3mWrcvrjB4j/ySg==
Digital signature. See digital signature
forming.
Attention! This notification is send on the checkout server via interaction link (InteractionURL)
up until SCI receives by present request status of HTTP-code from the checkout server, which is
specified in checkout settings (it is "200 OK" by default). Also, see checkout settings
“Confirmation text of successful receiving of notification about the status of payment”.
3.4.1. Checking payment information
To avoid the possibility of compromised notification of payment on the interaction page you need to
realize its checking, which is given below.
Besides that it is recommended to conduct additional data reconciliation of payment notification by API.
Verification of data source
In given checking, you need to certify that payment notification was sent directly by Interkassa and isn`t
compromised. For this, it is needed to check IP address of sender`s server (SCI). The address range that is
used by SCI you can view on the page “Interkassa IP addresses”. To authenticate the source of sender
and integrity of data digital signature is used (See digital signature forming).
Data checking
Despite the fact that notification is formed on the SCI side, ALLWAYS check such information of payment
notification as:




Checkout identifier (parameter "ik_co_id"). Should correspond to your checkout identifier.
Invoice amount (parameter "ik_am"). Should correspond to amount of your order for which it
was billed.
Invoice status (parameter "ik_inv_st"). Should correspond to value "success".
Digital signature (parameter "ik_sign"). See digital signature forming.
www.interkassa.com
Страница 16
3.5. Digital signature forming
Digital signature forms by combining of the values of all form parameters with “ik_” prefix in alphabetical
order of their names (case insensitive), with adding in the end “secret key” of the checkout.
Concatenation goes through ":" symbol. If form consists of some fields with the same names, such fields
are sorted in alphabetical order of their values.
Obtained field after combining of parameters and “secret key” value is hashed by selected method of
EDS forming and its bytes is in Base64 encoding.
ik_sign = Base64(MD5(Implode(Sort(Params) + SecretKey, ':'))));
Attention! Make sure that your hash function returns an array of bytes, not HEX representation.
If everything was done properly, than length of the ik_sign parameter consist of exact 24
symbols in MD5 hash-function.
Attention! If payment direction with which bill was paid is Test (ik_pw_via =
‘test_interkassa_test_xts’ ONLY FOR INTERACTION URL), than while digital signature forming
“Test secret key” is used. This is spread as to payment form forming, such as to payment
notification. See Testing.
Example of EDS forming algorithm in PHP language:
ksort($dataSet, SORT_STRING); // sort by the keys in alphabetical order array elements
array_push($dataSet, $key); // add in the end of array “secret key”
$signString = implode(':', $dataSet); // concatenate value through the ":" symbol
$sign = base64_encode(md5($signString, true)); // take MD5 hash in a binary form by the
formed line and encode in BASE64
return $sign; // return the result
Other examples of implementation in different programming languages are available on the web-site in
the chapter “Developers”.
4. Advanced features
4.1. Hidden SCI mode
4.1.1. Описание
Given mode is intended to receive payments via Interkassa with redirecting client when paying directly
onto payment system gateway. This allows your server, in the background for a client, receive data in
HTML-form which destined for payment through mentioned payment gateway. All that is required for
this is to use JSON interface with SCI that can be indicated by payment request form —"ik_int" with
"json" value.
4.1.2. Receiving of available for checkout list of payways
For receiving payment form for payment through payment system gateway, you need to specify such
values as: type of action "ik_act" — "payways”. And generate HTTP-request with payment form request
of payment onto SCI by POST or GET method, and receive in answer JSON-data packet of available for
payment of payways.
Example of request:
www.interkassa.com
Страница 17
<form name="payment"
<input type="hidden"
<input type="hidden"
<input type="hidden"
<input type="hidden"
<input type="hidden"
<input type="hidden"
<input type="submit"
</form>
method="post" action="https://sci.interkassa.com/"accept-charset="UTF-8">
name="ik_co_id" value="51237daa8f2a2d8413000000" />
name="ik_pm_no" value="ID_4233" />
name="ik_am" value="1.44" />
name="ik_desc" value="Payment Description" />
name="ik_act" value="payways" />
name="ik_int" value="json" />
value="Pay">
Example of answer:
{
"resultCode": 0,
"resultMsg": "Success",
"resultData": {
"paywaySet": [
{
"_id": "4f217ec98f2a2d4c0c0002d4",
"als": "privatterm_liqpay_merchant_uah",
"cur": "4e4147718f2a2d7014000467",
"curAls": "uah",
"in": "4e4147718f2a2d701400046e",
"inAls": "merchant",
"insInId": "4f674bd0e313d0f810000154",
"ps": "liqpay",
"ser": "privatterm",
"srt": "25"
},
{
"_id": "4f217ec98f2a2d4c0c0002d6",
"als": "anelik_w1_merchant_rub",
"cur": "4e4147718f2a2d701400047c",
"curAls": "rub",
"in": "4e4147718f2a2d7014000484",
"inAls": "merchant",
"insInId": "4f674bd0e313d0f81000014c",
"ps": "w1",
"ser": "anelik",
"srt": "36"
},
...
]
}
}
4.1.3. Receiving of data on the cost of payment on the payment gateway
For receiving payment form for payment through payment system gateway, you need to specify such
values as: type of action "ik_act" — "payway”, payment method "ik_pw_via" — <paywayalias> (any
available payment method, See Payway codes). And generate HTTP-request with payment form request
of payment onto SCI by POST or GET method, and receive in answer JSON-data packet of available for
payment of payways.
Example of request:
<form name="payment" method="post" action="https://sci.interkassa.com/"accept-charset="UTF-8">
<input type="hidden" name="ik_co_id" value="51237daa8f2a2d8413000000" />
<input type="hidden" name="ik_pm_no" value="ID_4233" />
www.interkassa.com
Страница 18
<input type="hidden"
<input type="hidden"
<input type="hidden"
<input type="hidden"
<input type="hidden"
<input type="submit"
</form>
name="ik_am" value="1.44" />
name="ik_desc" value="Payment Description" />
name="ik_int" value="json" />
name="ik_act" value="payway" />
name="ik_pw_via" value="webmoney_webmoney_merchant_wmz" />
value="Pay">
Example of answer:
{
"resultCode":0,
"resultMsg":"Success",
"resultData": {
"invoice": {
"checkoutId":"51237daa8f2a2d8413000000",
"checkoutPurseId":"307447812424",
"paymentNo":"218",
"paywayId":"4f217ec98f2a2d4c0c000318",
"paywayPurseId":"50d828d159d93cfb72000001",
"expired":1385305065,
"coAmount":5,
"coRefund":4.925,
"ikFee":0.15,
"ikFeeIn":0.075,
"ikFeeOut":0.075,
"ikPrice":5.075,
"psAmount":0.4323,
"psFeeIn":0,
"psFeeOut":3,
"psPrice":0.44,
"psExchRate":0.085166
}
}
}
4.1.4. Receiving data of payment form of payment gateway
For receiving payment form for payment through payment system gateway, you need to specify such
values as: type of action "ik_act" — "process”, payment method "ik_pw_via" — <paywayalias> (any
available payment method, See Payway codes). And generate HTTP-request with payment form request
of payment onto SCI by POST or GET method, and receive in answer JSON-data packet of available for
payment of payways.
Example of request:
<form name="payment"
<input type="hidden"
<input type="hidden"
<input type="hidden"
<input type="hidden"
<input type="hidden"
<input type="hidden"
<input type="hidden"
<input type="submit"
</form>
method="post" action="https://sci.interkassa.com/"accept-charset="UTF-8">
name="ik_co_id" value="51237daa8f2a2d8413000000" />
name="ik_pm_no" value="ID_4233" />
name="ik_am" value="1.44" />
name="ik_desc" value="Payment Description" />
name="ik_int" value="json" />
name="ik_act" value="process" />
name="ik_pw_via" value="webmoney_webmoney_merchant_wmz" />
value="Pay">
Example of answer:
www.interkassa.com
Страница 19
{
"resultCode": 0,
"resultMsg": "Success",
"resultData": {
"paymentForm": {
"action": "https://merchant.webmoney.ru/lmi/payment.asp" ,
"method": "post",
"parameters": {
"LMI_PAYEE_PURSE": "Z922208109129",
"LMI_PAYMENT_AMOUNT": "103.10",
"LMI_PAYMENT_DESC": "Payment No. IK15002746; Ноутбук Asus Z99LSeries",
"LMI_PAYMENT_NO": "15002746"
}
}
}
}
5. Testing
5.1. Creation of payment request form
For creation of simplified payment form, we offer you to use our payment generator of HTML-form. With
its assist, you can quickly create and configure payment request form, specify all necessary parameters
and settings and also to test it for redirecting client for payment via SCI.
5.2. Payment process and carrying out of payment
There is “Test payment system” for testing and carrying out of payment. It is turned on by default in the
new checkout as possible method of making the payment in your checkout.
Attention! If your checkout is already set and works out in open public mode, than you need to
turn off “Test payment system” in your checkout.
For making the test payment, you need only to pick up it for payment and press the button “Pay” or
chose other Action for payment. After this, SCI will redirect you onto the proper result page of your site.
Attention! When carrying out a payment via “Test payment system” transaction is not held! The
status of the billed invoice is changing, amount of the payment is not refunding on your balance.
Thus, you can test in full all process, as well as the processing of payment notification in your checkout
(InteractionForm). For this you need to use “test secret key”, that is available in checkout settings. Given
key is used for payment notification signature of the payment that was done only via “Test payment
system”.
Attention! Present mechanism, with “test secret key”, prevents a situation when you webapplication can credit the funds of the payment which was done via “test payment system”
according to transmitted data on the interaction page (InteractionURL). For this, ALLWAYS check
digital signature from SCI.
www.interkassa.com
Страница 20
6. Reference book
6.1. Currency codes
Actual information of the currency code is always available on the Interkassa web-site.
ID
Name
Character code
Figures code
10
Euro
EUR
978
20
Dollar
USD
840
30
Hryvnia
UAH
980
40
Russian ruble
RUB
643
50
Belorussian ruble
BYR
974
60
Gold (one troy pound)
XAU
959
99
Test currency
XTS
963
6.2. Code errors
Code
Alias
Message
100
E_IS_NOT_WORKING
SCI is not working. Try later...
101
E_PROTOCOL_NOT_EXIST
Protocol not exist
103
E_REQUEST_IS_EMPTY
Request is empty
102
E_INVALID_REQUEST_METHOD
Invalid request method
104
E_REQUEST_IS_NOT_SECURE
Request is not secure
106
E_PARAM_IS_NOT_SET
Parameter "%s" is not set
107
E_PARAM_IS_EMPTY
Parameter "%s" is empty
108
E_PARAM_INCORRECT_FORMAT
Parameter "%s" has incorrect format
109
E_PARAM_SET_FORBIDDEN
Parameter set "%s" forbidden
120
E_CHECKOUT_NOT_FOUND
Checkout is not found
121
E_CHECKOUT_UNAVAILABLE
Checkout is unavailable
122
E_CHECKOUT_CURRENCY_INVALID
Checkout has no purses with requested currency
115
E_REQUEST_SIGN_INVALID
Request sign "%s" is invalid
110
E_PAYMENT_NO_NOT_UNIQUE
Payment no "%s" must be unique
123
E_CHECKOUT_PURSE_UNAVAILABLE
Checkout purse is unavailable
www.interkassa.com
Страница 21
124
E_CHECKOUT_PAYWAY_UNAVAILABLE
Payway is unavailable for current checkout
125
E_CHECKOUT_PAYWAYS_UNAVAILABLE
Checkout has not any available payway
6.3. Payway codes
Actual information of the payway codes is always available on the Interkassa web-site.
Alias
Service
Gateway
Method
Currency
Alias
(IK 1.0)
privatterm_liqpay_merchant_uah
PrivatBank terminals
LiqPay
Merchant
UAH
liqpayterminal
u
anelik_w1_merchant_rub
Anelik
Wallet One
Merchant
RUB
w1anelikr
beeline_w1_merchant_rub
Beeline
Wallet One
Merchant
RUB
w1beeliner
contact_w1_merchant_rub
CONTACT
Wallet One
Merchant
RUB
w1contactr
lider_w1_merchant_rub
Leader
Wallet One
Merchant
RUB
w1liderr
megafon_w1_merchant_rub
Megafon
Wallet One
Merchant
RUB
w1megafonr
mobileretails_w1_merchant_rub
Mobile retails
Wallet One
Merchant
RUB
w1cashtermin
alr
mts_w1_merchant_rub
MTS
Wallet One
Merchant
RUB
w1mtsr
qiwiwallet_w1_merchant_rub
Qiwi Wallet
Wallet One
Merchant
RUB
w1qiwir
ruspost_w1_merchant_rub
Post of Russia
Wallet One
Merchant
RUB
w1ruspostr
rusterminal_w1_merchant_rub
Russian terminals
Wallet One
Merchant
RUB
w1terminalr
unistream_w1_merchant_rub
UNIStream
Wallet One
Merchant
RUB
w1unistreamr
webmoney_webmoney_merchant_wmb
WebMoney
WebMoney
Merchant
WMB
webmoneyb
webmoney_webmoney_merchant_wme
WebMoney
WebMoney
Merchant
WME
webmoneye
webmoney_webmoney_merchant_wmg
WebMoney
WebMoney
Merchant
WMG
webmoneyg
webmoney_webmoney_merchant_wmr
WebMoney
WebMoney
Merchant
WMR
webmoneyr
webmoney_webmoney_merchant_wmu
WebMoney
WebMoney
Merchant
WMU
webmoneyu
webmoney_webmoney_merchant_wmz
WebMoney
WebMoney
Merchant
WMZ
webmoneyz
nsmep_smartpay_invoice_uah
NSMEP
SmartPay
Invoicing
UAH
nsmep
yandexmoney_yandexmoney_merchant_
rub
Yandex.Money
Yandex.Mone
y
Merchant
RUR
yandexdengir
zpayment_zpayment_merchant_rub
Z-payment
Z-payment
Merchant
ZP RUB
zpaymentr
www.interkassa.com
Страница 22
sbrf_rusbank_receipt_rub
Sberbank RF
Russian Bank
Invoice
RUB
webmoney_webmoney_invoice_wmz
WebMoney
WebMoney
Invoicing
WMZ
webmoney_webmoney_invoice_wmu
WebMoney
WebMoney
Invoicing
WMU
webmoney_webmoney_invoice_wmr
WebMoney
WebMoney
Invoicing
WMR
webmoney_webmoney_invoice_wmg
WebMoney
WebMoney
Invoicing
WMG
webmoney_webmoney_invoice_wme
WebMoney
WebMoney
Invoicing
WME
webmoney_webmoney_invoice_wmb
WebMoney
WebMoney
Invoicing
WMB
webcreds_webcreds_merchant_rub
WebCreds
WebCreds
Merchant
RUB
webcreds
w1_w1_merchant_usd
Wallet One
Wallet One
Merchant
USD
w1z
w1_w1_merchant_uah
Wallet One
Wallet One
Merchant
UAH
w1u
w1_w1_merchant_rub
Wallet One
Wallet One
Merchant
RUB
w1r
w1_w1_merchant_eur
Wallet One
Wallet One
Merchant
EUR
w1e
visa_liqpay_merchant_usd
Visa
LiqPay
Merchant
USD
liqpaycardwz
visa_liqpay_merchant_rub
Visa
LiqPay
Merchant
RUB
liqpaycardwr
visa_liqpay_merchant_eur
Visa
LiqPay
Merchant
EUR
liqpaycardwe
ukrbank_ukrbank_receipt_uah
Ukrainian Bank
Ukrainian
Bank
Invoice
UAH
ukrbank
ukash_w1_merchant_usd
Ukash
Wallet One
Merchant
USD
w1ukashz
rusbank_rusbank_receipt_rub
Russian Bank
Russian Bank
Invoice
RUB
rusbank
rbkmoney_rbkmoney_merchant_rub
RBK Money
RBK Money
Merchant
RUB
rbkmoney
privat24_privat24_merchant_usd
Privat24
Privat24
Merchant
USD
privat24z
privat24_privat24_merchant_uah
Privat24
Privat24
Merchant
UAH
privat24u
privat24_privat24_merchant_eur
Privat24
Privat24
Merchant
EUR
privat24e
perfectmoney_perfectmoney_merchant_
usd
PerfectMoney
PerfectMoney
Merchant
USD
perfectmoneyz
perfectmoney_perfectmoney_merchant_
eur
PerfectMoney
PerfectMoney
Merchant
EUR
perfectmoney
e
moneymail_moneymail_merchant_usd
MoneyMail
MoneyMail
Merchant
USD
moneymailz
moneymail_moneymail_merchant_rub
MoneyMail
MoneyMail
Merchant
RUB
moneymailr
moneymail_moneymail_merchant_eur
MoneyMail
MoneyMail
Merchant
EUR
moneymaile
monexy_monexy_merchant_usd
MoneXy
MoneXy
Merchant
USD
monexyz
monexy_monexy_merchant_uah
MoneXy
MoneXy
Merchant
UAH
monexyu
monexy_monexy_merchant_rub
MoneXy
MoneXy
Merchant
RUR
monexyr
www.interkassa.com
Страница 23
sbrf
monexy_monexy_merchant_eur
MoneXy
MoneXy
Merchant
EUR
monexye
mastercard_liqpay_merchant_usd
Mastercard
LiqPay
Merchant
USD
liqpaycardwz
mastercard_liqpay_merchant_rub
Mastercard
LiqPay
Merchant
RUB
liqpaycardwr
mastercard_liqpay_merchant_eur
Mastercard
LiqPay
Merchant
EUR
liqpaycardwe
liqpay_liqpay_merchant_usd
LiqPay
LiqPay
Merchant
USD
liqpayz
liqpay_liqpay_merchant_uah
LiqPay
LiqPay
Merchant
UAH
liqpayu
liqpay_liqpay_merchant_rub
LiqPay
LiqPay
Merchant
RUB
liqpayr
liqpay_liqpay_merchant_eur
LiqPay
LiqPay
Merchant
EUR
liqpaye
libertyreserve_libertyreserve_merchant_
usd
Liberty Reserve
Liberty
Reserve
Merchant
USD
libertyz
libertyreserve_libertyreserve_merchant_
eur
Liberty Reserve
Liberty
Reserve
Merchant
EUR
libertye
eurobank_eurobank_receipt_usd
Wire Transfer
Wire Transfer
Invoice
USD
eurobank
paypal_paypal_merchant_usd
Paypal
Paypal
Merchant
USD
paypal
alfaclick_w1_merchant_rub
Alfasclick (Alfabank)
Wallet One
Merchant
RUB
w1alfaclick
interkassa_interkassa_voucher_usd
Interkassa
Interkassa
Voucher
USD
pincodez
visa_liqpay_merchant_uah
Visa
LiqPay
Merchant
UAH
liqpaycardu
mastercard_liqpay_merchant_uah
Mastercard
LiqPay
Merchant
UAH
liqpaycardu
rbkmoney_rbkmoney_merchantx_rub
RBK Money
RBK Money
Merchant
RUB
rbkmoneyx
telemoney_telemoney_merchant_rub
Telemoney
Telemoney
Merchant
RUR
telemoneyr
ukrterminal_w1_terminal_uah
Terminals of Ukraine
Wallet One
Terminal
UAH
w1terminalu
test_interkassa_test_xts
Test payment system
Interkassa
Test
XTS
7. Notes





Electronic digital signature
Billing
Processing
Codes
List of HTTP status codes
8. Links




Hash generator
Generator of payment form request
Interkassa API documentation
IP addresses of Interkassa
www.interkassa.com
Страница 24







Currency codes
Interkassa tariffs
Directory of payment methods
Examples of using
History of payment and no commission returns
Security questions
Examples of implementation of connecting in different programming languages
9. List of changes


v0.1: new documentation of SCI protocol
v0.8: added chapter "Advanced features"
www.interkassa.com
Страница 25