Ruby
Ruby
Decrypt a SAML Response
See more Encryption Examples
Demonstrates how to decrypt a SAML response.Chilkat Ruby Downloads
require 'chilkat'
success = false
# This example requires the Chilkat API to have been previously unlocked.
# See Global Unlock Sample for sample code.
# This example decrypts this SAML response:
# <?xml version="1.0" encoding="UTF-8" ?>
# <saml2p:Response Destination="https://deskflow-asp2.com/ubc/ubcdfe.dll/cwlacs" ID="_e4585eaeedbcaf7c24dff7f1ee2499f5" IssueInstant="2018-10-11T17:46:20.727Z" Version="2.0" xmlns:saml2p="urn:oasis:names:tc:SAML:2.0:protocol">
# <saml2:Issuer xmlns:saml2="urn:oasis:names:tc:SAML:2.0:assertion">https://authentication.stg.id.ubc.ca</saml2:Issuer>
# <ds:Signature xmlns:ds="http://www.w3.org/2000/09/xmldsig#">
# <ds:SignedInfo>
# <ds:CanonicalizationMethod Algorithm="http://www.w3.org/2001/10/xml-exc-c14n#"/>
# <ds:SignatureMethod Algorithm="http://www.w3.org/2001/04/xmldsig-more#rsa-sha256"/>
# <ds:Reference URI="#_e4585eaeedbcaf7c24dff7f1ee2499f5">
# <ds:Transforms>
# <ds:Transform Algorithm="http://www.w3.org/2000/09/xmldsig#enveloped-signature"/>
# <ds:Transform Algorithm="http://www.w3.org/2001/10/xml-exc-c14n#"/>
# </ds:Transforms>
# <ds:DigestMethod Algorithm="http://www.w3.org/2001/04/xmlenc#sha256"/>
# <ds:DigestValue>1ui22tqFyYEOoWI19CMwz4n+ynxNjLDGdTeRMdi60EU=</ds:DigestValue>
# </ds:Reference>
# </ds:SignedInfo>
# <ds:SignatureValue>ROg7FXV6vsp8socVhdo76/i7cRHGGKIveAiScKdujZT0QrHVqIvvbZ/RnwvEMJ9H9i/kJFAQA171
# Eo2kDjSdvNFQ/YcKaJUwMtAwT05yVatGV42RZKEf7ME+vpcCTR1LWZdrhat1FWCg1MNQwNWB0EL5
# fEP2a4jAcSTB8tFbjTAHsv7IWC39E5RVv99mACYXLa7iGZLtORANZxgYu5qQgmH6pUkI6Z1cpmf+
# m9mIjKM6LF0EvLfWOBWL6udZ+GsHPOLjVTJg+1S0xb9FQCYDVW1QhbjSS0icKHKTNNbrsaxllVDY
# m4q27YQjRh+XxugPgvsZ61Pxlto8Jbg+6jUlMQ==</ds:SignatureValue>
# <ds:KeyInfo>
# <ds:X509Data>
# <ds:X509Certificate>MIIDTTCCAjWgAwIBAgIVAJccYyIV6wly8XyddumpgnHMJ2JLMA0GCSqGSIb3DQEBCwUAMCcxJTAj
# BgNVBAMMHGF1dGhlbnRpY2F0aW9uLnN0Zy5pZC51YmMuY2EwHhcNMTcwMzAxMTk1NDM0WhcNMzcw
# ...
# xUuh6HuHKIwQqHBz7udxbH3Zbb6jXGDJjiDHt1LRJ8xbVisFIcDlIwsGQQi0HeEJfx4P</ds:X509Certificate>
# </ds:X509Data>
# </ds:KeyInfo>
# </ds:Signature>
# <saml2p:Status>
# <saml2p:StatusCode Value="urn:oasis:names:tc:SAML:2.0:status:Success"/>
# </saml2p:Status>
# <saml2:EncryptedAssertion xmlns:saml2="urn:oasis:names:tc:SAML:2.0:assertion">
# <xenc:EncryptedData Id="_314d80b9cf02d8eda8d686a6ffd626cf" Type="http://www.w3.org/2001/04/xmlenc#Element" xmlns:xenc="http://www.w3.org/2001/04/xmlenc#">
# <xenc:EncryptionMethod Algorithm="http://www.w3.org/2001/04/xmlenc#aes128-cbc" xmlns:xenc="http://www.w3.org/2001/04/xmlenc#"/>
# <ds:KeyInfo xmlns:ds="http://www.w3.org/2000/09/xmldsig#">
# <xenc:EncryptedKey Id="_d7b6da6fb59a627ebb4a96928441ab79" Recipient="https://ubcdfe.deskflow-asp2.com" xmlns:xenc="http://www.w3.org/2001/04/xmlenc#">
# <xenc:EncryptionMethod Algorithm="http://www.w3.org/2001/04/xmlenc#rsa-oaep-mgf1p" xmlns:xenc="http://www.w3.org/2001/04/xmlenc#">
# <ds:DigestMethod Algorithm="http://www.w3.org/2000/09/xmldsig#sha1" xmlns:ds="http://www.w3.org/2000/09/xmldsig#"/>
# </xenc:EncryptionMethod>
# <ds:KeyInfo>
# <ds:X509Data>
# <ds:X509Certificate>MIICuzCCAiQCCQD3bpigRnKMSzANBgkqhkiG9w0BAQsFADCBoTELMAkGA1UEBhMCQ0ExEDAOBgNV
# BAgMB09udGFyaW8xEDAOBgNVBAcMB1Rvcm9udG8xJjAkBgNVBAoMHVRhY3RpY2FsIEJ1c2luZXNz
# ...
# kVRcHd1UK3q7G8FoykWjdQz/0EoMTfEZ+Md56mLOe48eMUZV2ONZuL1kDCEKw1UwkaDQI4Pf8pzx
# 82b9rgw9wBDtvu5eFPlUGEGIBw==</ds:X509Certificate>
# </ds:X509Data>
# </ds:KeyInfo>
# <xenc:CipherData xmlns:xenc="http://www.w3.org/2001/04/xmlenc#">
# <xenc:CipherValue>BNHfUOpgdPE5BgpN2VIZIDthMAv1rxk91qVnWyCZOG9bmUKChJtTUqMpndot7VJwYuyKFshkAdnT
# D79KGdlSA1xHKcVeZXXzDWglqSyYjzhDCsyOhPaI4HelMFgCLwyFz89uEpUpqlvfl8ol3Am/XnzQ
# Vp7V7oS76hocjUI51Qs=</xenc:CipherValue>
# </xenc:CipherData>
# </xenc:EncryptedKey>
# </ds:KeyInfo>
# <xenc:CipherData xmlns:xenc="http://www.w3.org/2001/04/xmlenc#">
# <xenc:CipherValue>R6l7tmbnXrOfBgB8lA3KnwLYsLH5ZO5omQ7Hp5K05atzw2o55xmCXVMYhNneFxMtxUh6raEyHeZX
# PTZNgWrvdqc4GYND/R7MhRrJzk9OAq1WyoOXwbtRpwNDwWA4N2IuprPQJbvjVxaw/PesZMZwZqlp
# ...
# zm9zAxahyu8Ooe8M4r3HN2cY0JxxxkZtDiulbnyA+rRtXfBRJtangvFQ4iFAnzM/Yg9hMyW9jcu0
# S7FzuRB9ONMxi+nh0IFWgqp+</xenc:CipherValue>
# </xenc:CipherData>
# </xenc:EncryptedData>
# </saml2:EncryptedAssertion>
# </saml2p:Response>
# The sample encrypted SAML response and RSA private key are available online:
http = Chilkat::CkHttp.new()
sbSamlResponse = Chilkat::CkStringBuilder.new()
sbPrivateKeyPem = Chilkat::CkStringBuilder.new()
success = http.QuickGetSb("https://chilkatdownload.com/data/samlresponse.xml",sbSamlResponse)
if (success == true)
success = http.QuickGetSb("https://chilkatdownload.com/data/samlresponse_privkey.pem",sbPrivateKeyPem)
end
if (success == false)
print http.lastErrorText() + "\n";
exit
end
xml = Chilkat::CkXml.new()
xml.LoadSb(sbSamlResponse,true)
# Load the RSA private key..
privkey = Chilkat::CkPrivateKey.new()
success = privkey.LoadPem(sbPrivateKeyPem.getAsString())
if (success == false)
print privkey.lastErrorText() + "\n";
exit
end
# Prepare an RSA object w/ the private key...
rsa = Chilkat::CkRsa.new()
success = rsa.UsePrivateKey(privkey)
if (success == false)
print rsa.lastErrorText() + "\n";
exit
end
# RSA will be used to decrypt the xenc:EncryptedKey
# The bytes to be decrypted are in xenc:CipherValue (in base64 format)
encryptedAesKey = xml.getChildContent("saml2:EncryptedAssertion|xenc:EncryptedData|ds:KeyInfo|xenc:EncryptedKey|xenc:CipherData|xenc:CipherValue")
if (xml.get_LastMethodSuccess() != true)
print "Encrypted AES key not found." + "\n";
exit
end
print "Encrypted AES key (base64) = " + encryptedAesKey + "\n";
bdAesKey = Chilkat::CkBinData.new()
bdAesKey.AppendEncoded(encryptedAesKey,"base64")
sbRsaAlg = Chilkat::CkStringBuilder.new()
sbRsaAlg.Append(xml.chilkatPath("saml2:EncryptedAssertion|xenc:EncryptedData|ds:KeyInfo|xenc:EncryptedKey|xenc:EncryptionMethod|(Algorithm)"))
print "sbRsaAlg contains: " + sbRsaAlg.getAsString() + "\n";
if (sbRsaAlg.Contains("rsa-oaep",true) == true)
rsa.put_PkcsPadding(false)
end
success = rsa.DecryptBd(bdAesKey,true)
if (success == false)
print rsa.lastErrorText() + "\n";
exit
end
print "Decrypted AES key (hex) = " + bdAesKey.getEncoded("hex") + "\n";
# Get the encrypted XML (in base64) to be decrypted w/ the AES key.
encrypted64 = xml.getChildContent("saml2:EncryptedAssertion|xenc:EncryptedData|xenc:CipherData|xenc:CipherValue")
if (xml.get_LastMethodSuccess() != true)
print "Encrypted data not found." + "\n";
exit
end
bdEncrypted = Chilkat::CkBinData.new()
bdEncrypted.AppendEncoded(encrypted64,"base64")
# Get the symmetric algorithm: "http://www.w3.org/2001/04/xmlenc#aes128-cbc"
# and set the symmetric decrypt properties.
crypt = Chilkat::CkCrypt2.new()
sbAlg = Chilkat::CkStringBuilder.new()
sbAlg.Append(xml.chilkatPath("saml2:EncryptedAssertion|xenc:EncryptedData|xenc:EncryptionMethod|(Algorithm)"))
if (sbAlg.Contains("aes128-cbc",true) == true)
crypt.put_CryptAlgorithm("aes")
crypt.put_KeyLength(128)
crypt.put_CipherMode("cbc")
# The 1st 16 bytes of the encrypted data are the AES IV.
crypt.SetEncodedIV(bdEncrypted.getEncodedChunk(0,16,"hex"),"hex")
bdEncrypted.RemoveChunk(0,16)
end
# Other algorithms, key lengths, etc, can be supported by checking for different Algorithm attribute values..
crypt.SetEncodedKey(bdAesKey.getEncoded("hex"),"hex")
# AES decrypt...
success = crypt.DecryptBd(bdEncrypted)
if (success == false)
print crypt.lastErrorText() + "\n";
exit
end
# Get the decrypted XML
decryptedXml = bdEncrypted.getString("utf-8")
print "Decrypted XML:" + "\n";
print decryptedXml + "\n";
# The decrypted XML looks like this:
# <saml2:Assertion xmlns:saml2="urn:oasis:names:tc:SAML:2.0:assertion" ID="_226e565c548db7986d165d7d969b48b4" IssueInstant="2018-10-11T17:46:20.727Z" Version="2.0">
# ...
# ...
# ...
# </saml2:Assertion>
xmlAssertion = Chilkat::CkXml.new()
xmlAssertion.LoadXml(decryptedXml)
# Replace the saml2:EncryptedAssertion XML subtree with the saml2:Assertion XML.
# xmlEncryptedAssertion is a CkXml
xmlEncryptedAssertion = xml.FindChild("saml2:EncryptedAssertion")
xmlEncryptedAssertion.SwapTree(xmlAssertion)
# The decrypted XML assertion has now replaced the encrypted XML assertion.
# Examine the fully decrypted XML document:
print "Full XML SAML document with decrypted assertion:" + "\n";
print xml.getXml() + "\n";