demos/cms/cms_comp.c

   1 /* Simple S/MIME compress example */
   2 #include <openssl/pem.h>
   3 #include <openssl/cms.h>
   4 #include <openssl/err.h>
   5
   6 int main(int argc, char **argv)
   7 {
   8     BIO *in = NULL, *out = NULL;
   9     CMS_ContentInfo *cms = NULL;
  10     int ret = 1;
  11
  12     /*
  13      * On OpenSSL 1.0.0+ only:
  14      * for streaming set CMS_STREAM
  15      */
  16     int flags = CMS_STREAM;
  17
  18     OpenSSL_add_all_algorithms();
  19     ERR_load_crypto_strings();
  20
  21     /* Open content being compressed */
  22
  23     in = BIO_new_file("comp.txt", "r");
  24
  25     if (!in)
  26         goto err;
  27
  28     /* compress content */
  29     cms = CMS_compress(in, NID_zlib_compression, flags);
  30
  31     if (!cms)
  32         goto err;
  33
  34     out = BIO_new_file("smcomp.txt", "w");
  35     if (!out)
  36         goto err;
  37
  38     /* Write out S/MIME message */
  39     if (!SMIME_write_CMS(out, cms, in, flags))
  40         goto err;
  41
  42     ret = 0;
  43
  44  err:
  45
  46     if (ret) {
  47         fprintf(stderr, "Error Compressing Data\n");
  48         ERR_print_errors_fp(stderr);
  49     }
  50
  51     if (cms)
  52         CMS_ContentInfo_free(cms);
  53     if (in)
  54         BIO_free(in);
  55     if (out)
  56         BIO_free(out);
  57
  58     return ret;
  59
  60 }