# Tricks to get Cybersource Credit card processing post to work

**URL:** <https://clarionhub.com/t/tricks-to-get-cybersource-credit-card-processing-post-to-work/9068>\
**Category:** tips\
**Tags:** api\
**Created:** [April 23, 2026, 3:00pm UTC](https://clarionhub.com/t/tricks-to-get-cybersource-credit-card-processing-post-to-work/9068 "2026-04-23T15:00:08Z")\
**Posts on this page:** 1\
**Page:** 1

<div class="post-metadata">

**Author:** ![JeffH](https://clarionhub.com/letter_avatar_proxy/v4/letter/j/258eb7/32.png) [@JeffH](https://clarionhub.com/u/JeffH)\
**Post date:** [April 23, 2026, 3:00pm UTC](https://clarionhub.com/t/tricks-to-get-cybersource-credit-card-processing-post-to-work/9068/1 "2026-04-23T15:00:09Z")

</div>

MAP  
CyberSource:GenerateSignatureFromParams PROCEDURE (STRING signatureParams,STRING secretKey),STRING  
END

MAP  
CyberSource:GenerateHeader PROCEDURE (\*typCCRetailMsg ccMsg, \*NetWebClient pWeb, STRING PostString)  
END

CyberSource:GenerateSignatureFromParams PROCEDURE (STRING signatureParams,STRING secretKey)

strParams StringTheory  
strKey StringTheory

CODE

strParams.SetValue(signatureParams,st:clip)  
strKey.SetValue(secretKey,st:clip)  
strKey.Base64Decode()  
! strParams.ToUnicode()  
strParams.SetValue(NetMakeHMAC(strParams.GetValuePtr(), strParams.Length(), strKey.GetValue(), net:CALG\_SHA\_256))  
strParams.Base64Encode()  
return strParams.GetValue()

CyberSource:GenerateHeader PROCEDURE (\*typCCRetailMsg ccMsg, \*NetWebClient pWeb, STRING PostString)

lSecretKey STRING(100)  
KeyId STRING(100)  
MerchantId STRING(100)  
HostName STRING(100)  
HostTarget STRING(100)

strPost StringTheory  
strHost StringTheory

strURL StringTheory

sGMTDate STRING(64)

lstart LONG  
lend LONG

CODE

```
  MerchantId = ccMsg.AcctNo
  KeyId = ccMsg.Key
  lSecretKey = ccMsg.PW

  strURL.SetValue(ccMsg.TxnURL)
  
  lstart = 0
  lend = 0
  
  HostName = CLIP(strURL.FindBetween('https://', '.com', lstart, lend)) & '.com'
  lstart = 0
  lend = 0

  HostTarget = 'post /' & CLIP(strURL.FindBetween('.com/', '', lstart, lend))

  strPost.SetValue(CLIP(PostString))
  strPost.SetValue(NetMakeHash(strPost.GetValuePtr(),strPost.Length(),net:CALG_SHA_256))
  strPost.Base64Encode()

  sGMTDate = pWeb.CreateGMTDate()  

  strHost.SetValue('host: ' & CLIP(HostName) & '<10>' &|
                               'v-c-date: ' & CLIP(sGMTDate) & '<10>' & |
                               'request-target: ' & CLIP(HostTarget) & '<10>' &|
                               'digest: SHA-256=' & strPost.GetValue() & '<10>' &|
                               'v-c-merchant-id: ' & CLIP(MerchantId) & '')

  pWeb.CustomHeader = |
                               'v-c-merchant-id: ' & CLIP(MerchantId) & '<13,10>' &|
                               'v-c-date: ' & CLIP(sGMTDate) & '' & '<13,10>' &|
                               'digest: SHA-256=' & strPost.GetValue() & '<13,10>' &|
                               'Signature: keyid="' & CLIP(KeyId) & '", algorithm="HmacSHA256",' &|
                               ' headers="host v-c-date request-target digest v-c-merchant-id", signature="' &|
                               CyberSource:GenerateSignatureFromParams(strHost.GetValue(), lSecretKey) & '"'

```