(Python) Sign and Encrypt using Cert to produce -----BEGIN PKCS7----- ... -----END PKCS7-----

Demonstrates how to first sign content using your own cert + private key to produce PKCS7 binary output. Then encrypt the signed binary output using the recipient's public key to produce output such as:

-----BEGIN PKCS7-----
MIIHPwYJKoZIhvcNAQcEoIIHMDCCBywC ...
...
...
-----END PKCS7-----

Chilkat Python Downloads install with pip pip3 install chilkat or download... Python Module for Windows, MacOS, Linux, Alpine Linux, Solaris

import sys
import chilkat

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

crypt = chilkat.CkCrypt2()

toBeSignedAndEncrypted = "This string is to be signed and then encrypted."

myCert = chilkat.CkCert()
success = myCert.LoadPfxFile("qa_data/pfx/cert_test123.pfx","test123")
if (success != True):
    print(myCert.lastErrorText())
    sys.exit()

success = crypt.SetSigningCert(myCert)
if (success != True):
    print(crypt.lastErrorText())
    sys.exit()

#  Get the PKCS7 output in base64 format.
crypt.put_EncodingMode("base64")
#  Perhaps we don't want the entire cert chain to be included in the signature?
crypt.put_IncludeCertChain(False)
signedPkcs7 = crypt.opaqueSignStringENC(toBeSignedAndEncrypted)

#  We're going to encrypt the binary PKCS7 signature (which contains the content)
bdPkcs7 = chilkat.CkBinData()
bdPkcs7.AppendEncoded(signedPkcs7,"base64")

#  ---------------------------------------------------
#  Now for the encryption...

#  Specify the encryption to be used.
#  "pki" indicates "Public Key Infrastructure" and will create a PKCS7 encrypted (enveloped) message.
crypt.put_CryptAlgorithm("pki")
crypt.put_Pkcs7CryptAlg("aes")
crypt.put_KeyLength(128)
crypt.put_OaepHash("sha256")
crypt.put_OaepPadding(True)

#  A certificate is needed as the encryption key..
cert = chilkat.CkCert()
success = cert.LoadFromFile("qa_data/certs/testCert.pem")
if (success != True):
    print(cert.lastErrorText())
    sys.exit()

#  Tell the crypt object to use the certificate.
crypt.SetEncryptCert(cert)

success = crypt.EncryptBd(bdPkcs7)
if (success != True):
    print(crypt.lastErrorText())
    sys.exit()

#  Make a "-----BEGIN PKCS7-----" ... "-----END PKCS7-----" sandwich...
sb = chilkat.CkStringBuilder()
sb.AppendLine("-----BEGIN PKCS7-----",True)
sb.Append(bdPkcs7.getEncoded("base64_mime"))
sb.AppendLine("-----END PKCS7-----",True)

outStr = sb.getAsString()

print(outStr)

#  Sample output:

#  -----BEGIN PKCS7-----
#  MIIMFQYJKoZIhvcNAQcDoIIMBjCCDAICAQAxggH5MIIB9QIBADCBsTCBmzELMAkGA1UEBhMCR0Ix
#  GzAZBgNVBAgTEkdyZWF0ZXIgTWFuY2hlc3RlcjEQMA4GA1UEBxMHU2FsZm9yZDEaMBgGA1UEChMR
#  Q09NT0RPIENBIExpbWl0ZWQxQTA/BgNVBAMTOENPTU9ETyBTSEEtMjU2IENsaWVudCBBdXRoZW50
#  aWNhdGlvbiBhbmQgU2VjdXJlIEVtYWlsIENBAhEAuBl4qE2MODB05C5h53M5UDA4BgkqhkiG9w0B
#  AQcwK6APMA0GCWCGSAFlAwQCAQUAoRgwFgYJKoZIhvcNAQEIMAkGBSsOAwIaBQAEggEAA34hkvxY
#  TXMUAsWBmnRIvfFK920WeUVenM4ob7qibDiaXI2qWBgzkIfQH2T1vIYHHzNQuaaiTrK3THn8Nzfy
#  RFqTnhfWwsIL/yinHVn5rA9CbHFmxqHr2UctZxLB7x/DxV7pjqpTTveCwgC9FykxGBcNO92Thlho
#  bHyq1VM+tm4ppkyV982xL1VAIUX6BvqRlfPsB3hJsdGz/Z3HBdLNgkp2z8mMcLZx9vXwZ3Nyrsi1
#  JqUP4wJ+HHYb5aJseE2UtrEh+s/eq+49OS9BhAWKRlmTxZo8XSQPNeVIRt0HvFAr/+E+jiyASI7b
#  9mjPPWP36ia4+/yhUwchnD/bJxa5gjCCCf4GCSqGSIb3DQEHATAdBglghkgBZQMEAQIEEFApbYsk
#  2qdwHv7dkngFg3CAggnQiMpHuoyOxSilO2lowI73vwX44PKKu1aGFW+mCbne/UZfOAgbvpHQ1LcP
#  Nam+I8MZRtT7nqN3ZWIIvW468z2Z8ne4DqO/D0adlSwE66Z2JxkZncrUM+QR1Oo9sz7aY0eUxzeB
#  5yTUcm3gZSFsKJ0czKzxF7r8IE2ytRVjYWbSZ4eGcJ9Pjpxk38+IZTkcWyzreOCSE9NvH+mefJHT
#  IeTH05w96Rei5YEq1Zn41+bw/Yh19hKHarudAerA1v5f36gz/eWMF2VF5/D23dW3tbw1DpDc/96B
#  3Mu4/Z1CREQ1C6NLlRHIoULADScuzyQTlmbj2v7vBJa46GZvjswyDbALIJ7B026JHpSUCPcf90q4
#  qlAoOjLCOSEMb8qhHHchwEaHcydCRB1bschj+eBHJp6R3spbQXCtRnSLuvTdBSPVR5sD140q8f68
#  YHyozbBWkxp5vv6fOyQMBibUhW7tyLod7M4pcgZlSKE6v9qhOCnE5Ym+wkX/t78E+W1wflmAwVJo
#  WZXoJNul6b6Ith9nCWwX3d6iJY/mdapaqabFGV2qFu1MG1wiKzrZtl/5qbVNXeraLLOTBW+hPeNt
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#  m1akNtXeQhfE3bj2tlYkviuBYtetwIGos9y74XCQWkours/5as6WqKozYHpFigPB3OLdWbq2txxc
#  k741BL/Mw5ugtHmPqNzRn4txMvB+lAcE1y75sESqC774bSCmrn+uVmOTZFvNob0dhZNTGsbcLCTe
#  LLGS3ZUscah/9iVte5xGnsCOSq18PjPIdqMvzSEcrYQVyqe2/68mae6dpk7gyeiTYpDsSYO+KaHw
#  bwwViPnVOhRkXxU54unymiSmgIRrhn+hsbkxvJk3Q307a7wcj+/ygw5stTV2hLmIQotMvmlpFTLZ
#  PhB5eyFIZaWKV8XJgPV5JInrm39taw8ClHeSC31BNgfkX5u2h0pA1f5zMZ/SvgriW0Xumyoy/9XC
#  eVL6fCZEWmaRZbAy5RlVELR/N2/Z5VS6s8U6Wrck9Zq9sGelf+0QWbCEwNoxQf+xxH55QnzHRvpu
#  s839qRy/5msXSYno0fl3uE6cP/bWwk0Rvt3QYp75UTZDkfXl0ywy00V6AMPssKlDZe0GYWaqcHqz
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#  DysgV1FCCN8fGWRvbe7R74KR8SYwUOSAE63PDtGDWK345sOQXp5b0Vv4lVG5/ECZqYCM9RixLsyx
#  vrozd8L0wqQJ5vlMOt9wksSYa8zzShC/tO3aGyw9NLz6y3lKoz3NfA04k8IyT2wtx2cG82h4bdwo
#  aBPdFlV9P/WlVPJXgRv0GFJFX4HiVMQBEn3Rj8H/BHzZYPo9tLnPRmuoTWv+HaoAEzxwQ4O+L9av
#  0BO0eJSJNxs3UTaxl/psm17EinNLCV7lx7jKppj8v7Xxdem0+Fu0ME92XmFKG52tT9XkniF6orNP
#  9G48f93G7tIx4CLNT5QXhnUejZG0v0uBxnL5dURV4W/49Qg49lEZZr6yUZlDUhMBSKwCW/gcTeGv
#  XVscW4UaGH9ewPFYVHNaDh7ehxkaTtuTrVpS7fPhaWLwozR1ro+U/WIqjE7QeharK+eqJN7OJNcV
#  vx42zsCCzAankT70bGsEqtA/il4IbxEa3EQTqOMLdxSJ/62IZRKGNxwZnRou8i1pswMM5q/9/ITi
#  MweZHH+AWeXrf5CLVObq2ZPk6NUPScFKSy7Vao1SxORhj+YJDd3vznWpjjq88Qs1ntwitY13jnxh
#  58XEwI+vkjAY34lOEtr2UGXS0DrANN0//VMk40WZat5rVnx9XITC9RmGFvtM0RDgMZ3BOEXyI1mI
#  nGLILcAVW+mnxJcafwFCbI1nd6KyfQU+/RmXdOLPtKMjEKm2jBZt3UGaxLkHKCuzESdYtlUkbbcL
#  K5ynNEANfBNJjf494Sd+jbKe9031E7bl4nbQGFpmJDEnszWfKMdg9ChlOfYLM26pFN0hQahA26fn
#  PgrBYvKaHauR0SUPtibwmy2kIdKoakJoIvyDDYh6HHrdcwGVHfA5nCSFIHGsv3lcdLc2sMq38TR/
#  zh7verXj0Aa71VFfmxBrRvasvdp9ms7GZFzDzMq2yf+a4knzTdRHtst6jOoTXb0RXJuLfvDTJqmF
#  tue95J8OELZOpWnp21Yj52So78BlcOC4W3VexT4hyHhtziG9BKeXvc6WSU1pUEoNkXAXXrHLi/AG
#  lC45zJ+LzDp/3rOzGQ5SIIi67ZSSQNiW85ektAoSEJZlZ1xaXt9DEbugpkySfjI/GFxSmFZqCs6h
#  RNT4f8BAKX56ItobBORZbvk12Mn5QrxIEGFbOFcLt6cA/zqixS8ej1cz+SsMUkuzl/KDh6ncXeuF
#  2DawyL7/konWins6Jo3gYhRgw4fpck14aaEF5/+h3FvgVw23FieWYc6AImn/2zvtv6+gCJl7YnrG
#  9zSjHx2Kf7WRiFbpSqYXGGA0iD0b7So9oyrTItepIRQh0OFcDhCGXvhl2Sb7IQM7sL3WvbAHcseS
#  0xJiEIZogWbVKL5OqAn/VrJsL+0atvkh6qy5FVmk9CBWh92lkmwWyk8+CoTVC6DPMRXLv/MQar2W
#  j0cOL12vohVJe9MSHTMR6kHaaxj1J8b5AswZTBsbgFo16Q6ihxLC1fd70OM1c6Hak341UgCxHsOr
#  j9JfT+r5jpK3booIzBorGNJOkAuaBAEKdcnNpyCP2sDCzG+7Ws1H+lJzXVDXARftZSbMvfLctU49
#  5YZl+bBifBF8fSSSRNKXMbPeyww1idjezWKiXQC3hA6VPKtW7rn1py7hTlkdm6os1jW9vmSmz30j
#  KHvey6Kcy+fdc1gyYmXhSDD55uYVrj1JmbaZvIeGTh8cQ8E4Dsq2Hy2PQ8S2e2S6YcJ9X6yNkwXG
#  KrqG2vK4AeBuro1IfoUG1EJ17Q==
#  -----END PKCS7-----