Add openconnect_md5() function for NTLMv2

Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

gnutls.c

@@ -2139,6 +2139,19 @@ int openconnect_sha1(unsigned char *result, void *data, int datalen)
 	return 0;
 }
 
+int openconnect_md5(unsigned char *result, void *data, int datalen)
+{
+	gnutls_datum_t d;
+	size_t md5len = MD5_SIZE;
+
+	d.data = data;
+	d.size = datalen;
+	if (gnutls_fingerprint(GNUTLS_DIG_MD5, &d, result, &md5len))
+		return -1;
+
+	return 0;
+}
+
 int openconnect_random(void *bytes, int len)
 {
 	if (gnutls_rnd(GNUTLS_RND_RANDOM, bytes, len))

openconnect-internal.h

@@ -533,6 +533,7 @@ int cstp_handshake(struct openconnect_info *vpninfo, unsigned init);
 int get_cert_md5_fingerprint(struct openconnect_info *vpninfo, OPENCONNECT_X509 *cert,
 			     char *buf);
 int openconnect_sha1(unsigned char *result, void *data, int len);
+int openconnect_md5(unsigned char *result, void *data, int len);
 int openconnect_random(void *bytes, int len);
 int openconnect_local_cert_md5(struct openconnect_info *vpninfo,
 			       char *buf);

openssl.c

@@ -44,6 +44,17 @@ int openconnect_sha1(unsigned char *result, void *data, int len)
 	return 0;
 }
 
+int openconnect_md5(unsigned char *result, void *data, int len)
+{
+	EVP_MD_CTX c;
+
+	EVP_MD_CTX_init(&c);
+	EVP_Digest(data, len, result, NULL, EVP_md5(), NULL);
+	EVP_MD_CTX_cleanup(&c);
+
+	return 0;
+}
+
 int openconnect_get_cert_DER(struct openconnect_info *vpninfo,
 			     OPENCONNECT_X509 *cert, unsigned char **buf)
 {