--- a/common/certhelp.h	Mon Sep 29 13:02:41 2014 +0200
+++ b/common/certhelp.h	Mon Sep 29 13:12:58 2014 +0200
@@ -24,6 +24,12 @@
 #define CERT_OID_O      (unsigned char *)OID_AT_ORGANIZATION "\0"
 #define CERT_OID_OU     (unsigned char *)OID_AT_ORG_UNIT "\0"
 #define CERT_OID_SN     (unsigned char *)OID_AT_SERIAL_NUMBER "\0"
+
+#ifdef WIN32
+#include <windows.h>
+#include <wincrypt.h>
+#endif
+
 #ifdef __cplusplus
 extern "C" {
 #endif
@@ -58,6 +64,23 @@
  */
 char *x509_parse_subject(unsigned char *derdata, size_t derlen,
                          unsigned char *oid);
+
+#ifdef WIN32
+/**
+ * @brief Parse a X509 ASN encoded base64 encoded certificate.
+ *
+ * This function creates a Windows cert contect for the certificate
+ * encoded in b64_data. The new certificate has to be freed with
+ * CertFreeCertificateContext.
+ *
+ * @param[in] b64_data pointer to the certificate data.
+ * @param[in] b64_size sizeof the the data. (Without terminating \0)
+ *
+ * @returns NULL on error.
+ */
+PCCERT_CONTEXT b64_to_cert_context(char *b64_data, size_t b64_size);
+#endif
+
 #ifdef __cplusplus
 }
 #endif