PKCS7_encrypt_ex
p7 = PKCS7_encrypt_ex(encerts, in, cipher, flags, libctx, app_get0_propq());
return PKCS7_encrypt_ex(certs, in, cipher, flags, NULL, NULL);
PKCS7 *PKCS7_encrypt_ex(STACK_OF(X509) *certs, BIO *in,