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Unicode 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 Unicode C Downloads

Unicode C
#include <C_CkCrypt2W.h>
#include <C_CkCertW.h>
#include <C_CkBinDataW.h>
#include <C_CkStringBuilderW.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkCrypt2W crypt;
    const wchar_t *toBeSignedAndEncrypted;
    HCkCertW myCert;
    const wchar_t *signedPkcs7;
    HCkBinDataW bdPkcs7;
    HCkCertW cert;
    HCkStringBuilderW sb;
    const wchar_t *outStr;

    success = FALSE;

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

    crypt = CkCrypt2W_Create();

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

    myCert = CkCertW_Create();
    success = CkCertW_LoadPfxFile(myCert,L"qa_data/pfx/cert_test123.pfx",L"test123");
    if (success != TRUE) {
        wprintf(L"%s\n",CkCertW_lastErrorText(myCert));
        CkCrypt2W_Dispose(crypt);
        CkCertW_Dispose(myCert);
        return;
    }

    success = CkCrypt2W_SetSigningCert(crypt,myCert);
    if (success != TRUE) {
        wprintf(L"%s\n",CkCrypt2W_lastErrorText(crypt));
        CkCrypt2W_Dispose(crypt);
        CkCertW_Dispose(myCert);
        return;
    }

    // Get the PKCS7 output in base64 format.
    CkCrypt2W_putEncodingMode(crypt,L"base64");
    // Perhaps we don't want the entire cert chain to be included in the signature?
    CkCrypt2W_putIncludeCertChain(crypt,FALSE);
    signedPkcs7 = CkCrypt2W_opaqueSignStringENC(crypt,toBeSignedAndEncrypted);

    // We're going to encrypt the binary PKCS7 signature (which contains the content)
    bdPkcs7 = CkBinDataW_Create();
    CkBinDataW_AppendEncoded(bdPkcs7,signedPkcs7,L"base64");

    // ---------------------------------------------------
    // Now for the encryption...

    // Specify the encryption to be used.
    // "pki" indicates "Public Key Infrastructure" and will create a PKCS7 encrypted (enveloped) message.
    CkCrypt2W_putCryptAlgorithm(crypt,L"pki");
    CkCrypt2W_putPkcs7CryptAlg(crypt,L"aes");
    CkCrypt2W_putKeyLength(crypt,128);
    CkCrypt2W_putOaepHash(crypt,L"sha256");
    CkCrypt2W_putOaepPadding(crypt,TRUE);

    // A certificate is needed as the encryption key..
    cert = CkCertW_Create();
    success = CkCertW_LoadFromFile(cert,L"qa_data/certs/testCert.pem");
    if (success != TRUE) {
        wprintf(L"%s\n",CkCertW_lastErrorText(cert));
        CkCrypt2W_Dispose(crypt);
        CkCertW_Dispose(myCert);
        CkBinDataW_Dispose(bdPkcs7);
        CkCertW_Dispose(cert);
        return;
    }

    // Tell the crypt object to use the certificate.
    CkCrypt2W_SetEncryptCert(crypt,cert);

    success = CkCrypt2W_EncryptBd(crypt,bdPkcs7);
    if (success != TRUE) {
        wprintf(L"%s\n",CkCrypt2W_lastErrorText(crypt));
        CkCrypt2W_Dispose(crypt);
        CkCertW_Dispose(myCert);
        CkBinDataW_Dispose(bdPkcs7);
        CkCertW_Dispose(cert);
        return;
    }

    // Make a "-----BEGIN PKCS7-----" ... "-----END PKCS7-----" sandwich...
    sb = CkStringBuilderW_Create();
    CkStringBuilderW_AppendLine(sb,L"-----BEGIN PKCS7-----",TRUE);
    CkStringBuilderW_Append(sb,CkBinDataW_getEncoded(bdPkcs7,L"base64_mime"));
    CkStringBuilderW_AppendLine(sb,L"-----END PKCS7-----",TRUE);

    outStr = CkStringBuilderW_getAsString(sb);

    wprintf(L"%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-----


    CkCrypt2W_Dispose(crypt);
    CkCertW_Dispose(myCert);
    CkBinDataW_Dispose(bdPkcs7);
    CkCertW_Dispose(cert);
    CkStringBuilderW_Dispose(sb);

    }