(C) Extract PKCS7 from MIME and Decrypt

Extracts the base64-encoded PKCS7 body of a MIME message to a file, and then decrypts using Chilkat Crypt2.

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#include <C_CkMime.h>
#include <C_CkCrypt2.h>

void ChilkatSample(void)
    {
    HCkMime mime;
    BOOL success;
    HCkCrypt2 crypt;
    const char *inPath;
    const char *outPath;

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

    mime = CkMime_Create();

    success = CkMime_LoadMimeFile(mime,"c:/aaworkarea/EmailInBytes.txt");
    if (success != TRUE) {
        printf("%s\n",CkMime_lastErrorText(mime));
        CkMime_Dispose(mime);
        return;
    }

    success = CkMime_SaveBody(mime,"c:/aaworkarea/smime.p7m");
    if (success != TRUE) {
        printf("%s\n",CkMime_lastErrorText(mime));
        CkMime_Dispose(mime);
        return;
    }

    crypt = CkCrypt2_Create();

    success = CkCrypt2_AddPfxSourceFile(crypt,"c:/aaworkarea/my.pfx","pfxPassword");
    if (success == FALSE) {
        printf("%s\n",CkCrypt2_lastErrorText(crypt));
        CkMime_Dispose(mime);
        CkCrypt2_Dispose(crypt);
        return;
    }

    // Indicate the public-key (PKCS7) encryption/decryption should be used:
    CkCrypt2_putCryptAlgorithm(crypt,"pki");

    inPath = "c:/aaworkarea/smime.p7m";
    outPath = "c:/aaworkarea/decrypted.dat";

    success = CkCrypt2_CkDecryptFile(crypt,inPath,outPath);
    if (success == FALSE) {
        printf("%s\n",CkCrypt2_lastErrorText(crypt));
        CkMime_Dispose(mime);
        CkCrypt2_Dispose(crypt);
        return;
    }

    printf("Success.\n");


    CkMime_Dispose(mime);
    CkCrypt2_Dispose(crypt);

    }