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C

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

See more Encryption Examples

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 C Downloads

C
#include <C_CkCrypt2.h>
#include <C_CkCert.h>
#include <C_CkBinData.h>
#include <C_CkStringBuilder.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkCrypt2 crypt;
    const char *toBeSignedAndEncrypted;
    HCkCert myCert;
    const char *signedPkcs7;
    HCkBinData bdPkcs7;
    HCkCert cert;
    HCkStringBuilder sb;
    const char *outStr;

    success = FALSE;

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

    crypt = CkCrypt2_Create();

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

    myCert = CkCert_Create();
    success = CkCert_LoadPfxFile(myCert,"qa_data/pfx/cert_test123.pfx","test123");
    if (success != TRUE) {
        printf("%s\n",CkCert_lastErrorText(myCert));
        CkCrypt2_Dispose(crypt);
        CkCert_Dispose(myCert);
        return;
    }

    success = CkCrypt2_SetSigningCert(crypt,myCert);
    if (success != TRUE) {
        printf("%s\n",CkCrypt2_lastErrorText(crypt));
        CkCrypt2_Dispose(crypt);
        CkCert_Dispose(myCert);
        return;
    }

    //  Get the PKCS7 output in base64 format.
    CkCrypt2_putEncodingMode(crypt,"base64");
    //  Perhaps we don't want the entire cert chain to be included in the signature?
    CkCrypt2_putIncludeCertChain(crypt,FALSE);
    signedPkcs7 = CkCrypt2_opaqueSignStringENC(crypt,toBeSignedAndEncrypted);

    //  We're going to encrypt the binary PKCS7 signature (which contains the content)
    bdPkcs7 = CkBinData_Create();
    CkBinData_AppendEncoded(bdPkcs7,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.
    CkCrypt2_putCryptAlgorithm(crypt,"pki");
    CkCrypt2_putPkcs7CryptAlg(crypt,"aes");
    CkCrypt2_putKeyLength(crypt,128);
    CkCrypt2_putOaepHash(crypt,"sha256");
    CkCrypt2_putOaepPadding(crypt,TRUE);

    //  A certificate is needed as the encryption key..
    cert = CkCert_Create();
    success = CkCert_LoadFromFile(cert,"qa_data/certs/testCert.pem");
    if (success != TRUE) {
        printf("%s\n",CkCert_lastErrorText(cert));
        CkCrypt2_Dispose(crypt);
        CkCert_Dispose(myCert);
        CkBinData_Dispose(bdPkcs7);
        CkCert_Dispose(cert);
        return;
    }

    //  Tell the crypt object to use the certificate.
    CkCrypt2_SetEncryptCert(crypt,cert);

    success = CkCrypt2_EncryptBd(crypt,bdPkcs7);
    if (success != TRUE) {
        printf("%s\n",CkCrypt2_lastErrorText(crypt));
        CkCrypt2_Dispose(crypt);
        CkCert_Dispose(myCert);
        CkBinData_Dispose(bdPkcs7);
        CkCert_Dispose(cert);
        return;
    }

    //  Make a "-----BEGIN PKCS7-----" ... "-----END PKCS7-----" sandwich...
    sb = CkStringBuilder_Create();
    CkStringBuilder_AppendLine(sb,"-----BEGIN PKCS7-----",TRUE);
    CkStringBuilder_Append(sb,CkBinData_getEncoded(bdPkcs7,"base64_mime"));
    CkStringBuilder_AppendLine(sb,"-----END PKCS7-----",TRUE);

    outStr = CkStringBuilder_getAsString(sb);

    printf("%s\n",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
    //  hb0XpWHtR28Ig1Y51P2wEGNoTsZrkJrOn8Go0mgHlWnUPLJImyDZYdJF6ZvlRhpSj/99RLHZORT7
    //  m1akNtXeQhfE3bj2tlYkviuBYtetwIGos9y74XCQWkours/5as6WqKozYHpFigPB3OLdWbq2txxc
    //  k741BL/Mw5ugtHmPqNzRn4txMvB+lAcE1y75sESqC774bSCmrn+uVmOTZFvNob0dhZNTGsbcLCTe
    //  LLGS3ZUscah/9iVte5xGnsCOSq18PjPIdqMvzSEcrYQVyqe2/68mae6dpk7gyeiTYpDsSYO+KaHw
    //  bwwViPnVOhRkXxU54unymiSmgIRrhn+hsbkxvJk3Q307a7wcj+/ygw5stTV2hLmIQotMvmlpFTLZ
    //  PhB5eyFIZaWKV8XJgPV5JInrm39taw8ClHeSC31BNgfkX5u2h0pA1f5zMZ/SvgriW0Xumyoy/9XC
    //  eVL6fCZEWmaRZbAy5RlVELR/N2/Z5VS6s8U6Wrck9Zq9sGelf+0QWbCEwNoxQf+xxH55QnzHRvpu
    //  s839qRy/5msXSYno0fl3uE6cP/bWwk0Rvt3QYp75UTZDkfXl0ywy00V6AMPssKlDZe0GYWaqcHqz
    //  xj2sOK++Iz0tlmhS6QWcGrgWyVaHG9E2van/yLE4Sl4qnKt88/vK+cTKCrRCStslrt2Z/1myLnaB
    //  6b6uAlVFk+kIHH82WaXxfCVedoGVk+jL3qPRbQiCzm7O66N6ecXIFWQ10sR5AXk/k4M6rM2Zhgoh
    //  yjPAxEHOzZ7nTLMb2MvPSV4KbrQT7Qs8prefY6o1OANXu4HRzL+zzttiIrV72vVemF80q7e5wYKR
    //  pGC85zZwz084RSWSwHTXDeWpI8zRPM7eboR97q9dfy7V23YlYJyM2RYrusweULib6X4me9nPhOzD
    //  4KmqI6FSOvwTUdEDb8k32+GVB+zXsEhI6uPFz+Fgve8WUKcWX0DFoD905+KICeDFlOxWjB5FhKqF
    //  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-----


    CkCrypt2_Dispose(crypt);
    CkCert_Dispose(myCert);
    CkBinData_Dispose(bdPkcs7);
    CkCert_Dispose(cert);
    CkStringBuilder_Dispose(sb);

    }