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C

Load .eml and Decrypt (smime.p7m)

Loads an encrypted email from a .eml file and decrypts using certificate w/ private key found in a .p12 (or .pfx) file.

The Content-Type and Content-Disposition email headers of the email to be decrypted look similar to this:

Content-Type: application/x-pkcs7-mime; smime-type=enveloped-data;
	name="smime.p7m"
Content-Disposition: attachment; filename="smime.p7m"

Chilkat C Downloads

C
#include <C_CkEmail.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkEmail email;

    success = FALSE;

    email = CkEmail_Create();

    // Add a PFX (or .p12) to be used for decryption
    success = CkEmail_AddPfxSourceFile(email,"myCert.p12","passwordForP12");
    if (success != TRUE) {
        printf("%s\n",CkEmail_lastErrorText(email));
        CkEmail_Dispose(email);
        return;
    }

    // Loading the .eml automatically decrypts.
    success = CkEmail_LoadEml(email,"encrypted.eml");
    if (success != TRUE) {
        printf("%s\n",CkEmail_lastErrorText(email));
        CkEmail_Dispose(email);
        return;
    }

    // The email now exists as it was prior to encryption.
    // Your app may access the email's subject, body, attachments,
    // etc. using the Chilkat Email API...

    // Save the decrypted email:
    success = CkEmail_SaveEml(email,"decrypted.eml");
    if (success != TRUE) {
        printf("%s\n",CkEmail_lastErrorText(email));
        CkEmail_Dispose(email);
        return;
    }

    printf("Success.\n");


    CkEmail_Dispose(email);

    }