(Tcl) RSAES-OAEP Encrypt/Decrypt Binary Data with AES-128 and SHA56

Demonstrates the use of the new EncryptBd and DecryptBd methods introduced in Chilkat v9.5.0.67 to create a PKCS7/CMS (Cryptographic Message Syntax) message using RSAES-OAEP with AES-128 and SHA256.

Note: This example requires Chilkat v9.5.0.67 or greater.

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load ./chilkat.dll

# This example requires the Chilkat Crypt API to have been previously unlocked.
# See Unlock Chilkat Crypt for sample code.

# Load a small JPG file to be encrypted/decrypted.
set jpgBytes [new_CkBinData]

set success [CkBinData_LoadFile $jpgBytes "qa_data/jpg/starfish20.jpg"]
if {$success != 1} then {
    puts "Failed to load JPG file."
    delete_CkBinData $jpgBytes
    exit
}

# Show the unencrypted JPG bytes in Base64 format.
# (The "base64_mime" encoding was added in Chilkat v9.5.0.67.
# The "base64" encoding emits a single line of base64, whereas
# "base64_mime" will emit multi-line base64 as it would appear
# in MIME.)
puts [CkBinData_getEncoded $jpgBytes base64_mime]

# Sample base64_mime JPG data:

# /9j/4AAQSkZJRgABAQEASABIAAD//gAmRmlsZSB3cml0dGVuIGJ5IEFkb2JlIFBob3Rvc2hvcD8g
# NC4w/9sAQwAQCwwODAoQDg0OEhEQExgoGhgWFhgxIyUdKDozPTw5Mzg3QEhcTkBEV0U3OFBtUVdf
# YmdoZz5NcXlwZHhcZWdj/9sAQwEREhIYFRgvGhovY0I4QmNjY2NjY2NjY2NjY2NjY2NjY2NjY2Nj
# Y2NjY2NjY2NjY2NjY2NjY2NjY2NjY2NjY2Nj/8IAEQgAFAAUAwERAAIRAQMRAf/EABcAAAMBAAAA
# AAAAAAAAAAAAAAIDBAX/xAAYAQADAQEAAAAAAAAAAAAAAAABAgMEAP/aAAwDAQACEAMQAAAB2kZY
# NNEijWKddfTmLgALWH//xAAbEAACAgMBAAAAAAAAAAAAAAABAgMRAAQSE//aAAgBAQABBQL0XqN+
# pM2aqJGMiqFFCyg7z//EABwRAAICAgMAAAAAAAAAAAAAAAERAAIQIQMSUf/aAAgBAwEBPwHqU5aq
# Axx+y1tMQl4elj//xAAcEQEAAQUBAQAAAAAAAAAAAAABEQACEBIhA1H/2gAIAQIBAT8B3Bhqy7Zc
# enyiwmGgDhiOzj//xAAdEAABAwUBAAAAAAAAAAAAAAABAAIREBIhIkFR/9oACAEBAAY/ArZyn+Cg
# xtxWuJaoCnqDuin/xAAcEAABBAMBAAAAAAAAAAAAAAABABEhYRAxQVH/2gAIAQEAAT8hkEwPUUR9
# DYfE4nxtRpIkBTsayuALIiuY/9oADAMBAAIAAwAAABDWPTsf/8QAGhEAAwADAQAAAAAAAAAAAAAA
# AAEREDFBIf/aAAgBAwEBPxC0DVPcWm+Ce4OesrkE6bjH/8QAGBEBAQEBAQAAAAAAAAAAAAAAAREA
# QRD/2gAIAQIBAT8QahMiOc8YgSrnTY3ELclHXn//xAAcEAEBAAIDAQEAAAAAAAAAAAABEQAhMUFx
# EFH/2gAIAQEAAT8Qn3igmSZSj+c4N4zapMy9IjFV98wncN2iuLFsCEbDGxQkI6RO/n//2Q==

set crypt [new_CkCrypt2]

# Specify the encryption to be used.
# "pki" indicates "Public Key Infrastructure" and will create a PKCS7/CMS message.
CkCrypt2_put_CryptAlgorithm $crypt "pki"
CkCrypt2_put_Pkcs7CryptAlg $crypt "aes"
CkCrypt2_put_KeyLength $crypt 128
CkCrypt2_put_OaepHash $crypt "sha256"
CkCrypt2_put_OaepPadding $crypt 1

# A certificate is needed as the encryption key..
set cert [new_CkCert]

set success [CkCert_LoadFromFile $cert "qa_data/rsaes-oaep/cert.pem"]
if {$success != 1} then {
    puts [CkCert_lastErrorText $cert]
    delete_CkBinData $jpgBytes
    delete_CkCrypt2 $crypt
    delete_CkCert $cert
    exit
}

# Tell the crypt object to use the certificate.
CkCrypt2_SetEncryptCert $crypt $cert

# Do the in-place RSAES-OAEP encryption.
# The contents of jpgBytes are replaced with the CMS message.
set success [CkCrypt2_EncryptBd $crypt $jpgBytes]
if {$success != 1} then {
    puts [CkCrypt2_lastErrorText $crypt]
    delete_CkBinData $jpgBytes
    delete_CkCrypt2 $crypt
    delete_CkCert $cert
    exit
}

# Examine the JPG bytes again.  The bytes should be different because they are encrypted:
puts [CkBinData_getEncoded $jpgBytes base64_mime]

# Sample CMS message:
# This CMS message can be copy-and-pasted into the online web form
# at https://lapo.it/asn1js/   to verify the algorithms used.

# MIIFDAYJKoZIhvcNAQcDoIIE/TCCBPkCAQAxggGgMIIBnAIBADB1MGgxCzAJBgNVBAYTAlVTMQsw
# CQYDVQQIDAJJTDEQMA4GA1UEBwwHV2hlYXRvbjEhMB8GA1UECgwYSW50ZXJuZXQgV2lkZ2l0cyBQ
# dHkgTHRkMRcwFQYDVQQDDA5DaGlsa2F0V2lkZ2V0cwIJAMRwugDmvniwMBwGCSqGSIb3DQEBBzAP
# oA0wCwYJYIZIAWUDBAIBBIIBAHyWLgkJfIvoA3cYEAR/uHfA7uoi4eQXHl2woQAd6W5BbUNVBcYD
# zuCTTOTWo1e7Uh0j0AhMZvVQf3+cngTiimzKwIZ2LNuNAgYOhrO/7coHyB22ImVetncUpCsAv/u7
# 2tYp1dO36T56K+2hMELwcQXTj6v5ODO6a3emdCjITCjHhlYePvq2l0HyU2ALG5RFB6ldk9imhKzn
# 6gfcijfH65S+KfMRlFBCXFu5nCBKmi8Ywo8Ue0rFssUDKLCjCeQNY52symiDbN/d06K/luOUwVhY
# 1KQffdIKmTrZUugw+FaoQRq0xGj39T/sYu8qCinNZu/vPdUmxcXszSaSVJ/LGwcwggNOBgkqhkiG
# 9w0BBwEwHQYJYIZIAWUDBAECBBDLnqRASqqnNUV2IiDkTRl/gIIDIPRaxdKEjhR5RD7pc7yI5j7N
# TioZNvuMETdHWgHy7eOGz+1hP7fObk/RI0mtQx7IPEjkxaduNbXNzTpXAVRVj4Fw1zzXlqh9UPwt
# p3TN3NsVRPQ5GmQ+cnPTSZD8i3i8ru8WFHyj1M6vyA0phrEGltKgqsZbb+OkuO5qG3laJv4XGkmn
# 039pPGSTydQzW+HAp/hsJZLEMwdngXToi854ytjEk+ahCkeOz+d2MAfXZAR+nBCkmAmCQ9SDVTqH
# FVJOAV2WrKBqNv4+iMn63f7QeoVIjk0QTE8D2iRsUiFYjy4ICaUpplLJEewneH5l0W40KA2+mOep
# lIrvWnaX2H8ltOEBGD6Jng7i6p/Q4Lr+Y+HBYIHsBPLox3A4NOh/b0MZcyBr/AV2CsIwkIUGLlYl
# /3rnpl7dRTuHP+fe1lDQVLAxD+U0c73sW7vOALhEe2t2Ae3ayukWPRyfXK9FNHAMhcOI4stHNSwx
# o2fHa+ctTpPh0V5CHY/ELAKKkrH3nW954pk52tc8Xt6CnzVO5ry/ndcmTlQA0PkG6CK98TE9hCTA
# hBdSL4/gVFgi9c35I6VXieY9kJe5ICljw5Ftm5yqTwlJIxGU3Z/WeIYBF4uyMegG75AQ9Md9tX0h
# w8OOu2b6sIvxOZ+durIrYQDlXUXU/IR9exzAlYFENNBPhBgtDsWKSx5gcp+32kC5wtSYSiy3JxNt
# 0W1yEJz8JGZXhuUvRXjwf+AjS4+/o82WTNXVLVKZ0TP50NVvtf9QqWuXvK/kDDPx6w+abK/aqdAs
# QSL7wCxOosR2YUPWbXtwGhyHbIfAwWXijO2RnrqKeXL25Ywg16LQUTHq9Mlbgfw/tx3l5pjrmqFC
# e9t9aaU6kDZqyyfRDOeWwkuDIsT90ulazbed2apgUXYj6AVVvMiC1pRld9wSuHH0vW0x5VsNbmXy
# EY0NJlJY6II/1szy3bpiP6MsqFveCyCX8rM7UgGgpMNbvWPnsX0F/0eJywIrXrnQYXpvfgghIrlr
# qu/ftXWypfcfvATxme+cN2EBsCDhq4VcMgB6JY3ykv6P8PK/QpMTbu4Y

# To decrypt, we'll need the cert with private key.  
# (The certificate alone contains only the public key.)
# Provide the required cert + private key from a PFX (.pfx/.p12) file.
set success [CkCrypt2_AddPfxSourceFile $crypt "qa_data/rsaes-oaep/cert_plus_privatekey.pfx" "PFX_PASSWORD"]
if {$success != 1} then {
    puts [CkCrypt2_lastErrorText $crypt]
    delete_CkBinData $jpgBytes
    delete_CkCrypt2 $crypt
    delete_CkCert $cert
    exit
}

# Decrypt to restore back to the original:
set success [CkCrypt2_DecryptBd $crypt $jpgBytes]
if {$success != 1} then {
    puts [CkCrypt2_lastErrorText $crypt]
    delete_CkBinData $jpgBytes
    delete_CkCrypt2 $crypt
    delete_CkCert $cert
    exit
}

puts [CkBinData_getEncoded $jpgBytes base64_mime]

delete_CkBinData $jpgBytes
delete_CkCrypt2 $crypt
delete_CkCert $cert