diff --git a/apps/s_client.c b/apps/s_client.c
index 2f13503..e38f16e 100644
--- a/apps/s_client.c
+++ b/apps/s_client.c
@@ -203,7 +203,6 @@
 #ifndef OPENSSL_NO_TLSEXT
 static int c_tlsextdebug=0;
 static int c_status_req=0;
-static int c_proof_debug=0;
 #endif
 static int c_msg=0;
 static int c_showcerts=0;
@@ -215,7 +214,8 @@
 static void print_stuff(BIO *berr,SSL *con,int full);
 #ifndef OPENSSL_NO_TLSEXT
 static int ocsp_resp_cb(SSL *s, void *arg);
-static int audit_proof_cb(SSL *s, void *arg);
+static int c_auth = 0;
+static int c_auth_require_reneg = 0;
 #endif
 static BIO *bio_c_out=NULL;
 static BIO *bio_c_msg=NULL;
@@ -223,6 +223,35 @@
 static int c_ign_eof=0;
 static int c_brief=0;
 
+#ifndef OPENSSL_NO_TLSEXT
+
+static const unsigned char *most_recent_supplemental_data;
+static size_t most_recent_supplemental_data_length;
+
+static int server_provided_server_authz = 0;
+static int server_provided_client_authz = 0;
+
+static const unsigned char auth_ext_data[]={TLSEXT_AUTHZDATAFORMAT_dtcp};
+
+static int suppdata_cb(SSL *s, unsigned short supp_data_type,
+		       const unsigned char *in,
+		       unsigned short inlen, int *al,
+		       void *arg);
+
+static int auth_suppdata_generate_cb(SSL *s, unsigned short supp_data_type,
+				     const unsigned char **out,
+				     unsigned short *outlen, void *arg);
+
+static int authz_tlsext_generate_cb(SSL *s, unsigned short ext_type,
+				    const unsigned char **out, unsigned short *outlen,
+				    void *arg);
+
+static int authz_tlsext_cb(SSL *s, unsigned short ext_type,
+			   const unsigned char *in,
+			   unsigned short inlen, int *al,
+			   void *arg);
+#endif
+
 #ifndef OPENSSL_NO_PSK
 /* Default PSK identity and key */
 static char *psk_identity="Client_identity";
@@ -362,14 +391,13 @@
 	BIO_printf(bio_err," -tlsextdebug      - hex dump of all TLS extensions received\n");
 	BIO_printf(bio_err," -status           - request certificate status from server\n");
 	BIO_printf(bio_err," -no_ticket        - disable use of RFC4507bis session tickets\n");
-	BIO_printf(bio_err," -proof_debug      - request an audit proof and print its hex dump\n");
+	BIO_printf(bio_err," -serverinfo types - send empty ClientHello extensions (comma-separated numbers)\n");
+	BIO_printf(bio_err," -auth               - send and receive RFC 5878 TLS auth extensions and supplemental data\n");
+	BIO_printf(bio_err," -auth_require_reneg - Do not send TLS auth extensions until renegotiation\n");
 # ifndef OPENSSL_NO_NEXTPROTONEG
 	BIO_printf(bio_err," -nextprotoneg arg - enable NPN extension, considering named protocols supported (comma-separated list)\n");
 	BIO_printf(bio_err," -alpn arg         - enable ALPN extension, considering named protocols supported (comma-separated list)\n");
 # endif
-#ifndef OPENSSL_NO_TLSEXT
-	BIO_printf(bio_err," -serverinfo types - send empty ClientHello extensions (comma-separated numbers)\n");
-#endif
 #endif
 	BIO_printf(bio_err," -legacy_renegotiation - enable use of legacy renegotiation (dangerous)\n");
 	BIO_printf(bio_err," -use_srtp profiles - Offer SRTP key management with a colon-separated profile list\n");
@@ -823,8 +851,10 @@
 			c_tlsextdebug=1;
 		else if	(strcmp(*argv,"-status") == 0)
 			c_status_req=1;
-		else if	(strcmp(*argv,"-proof_debug") == 0)
-			c_proof_debug=1;
+		else if	(strcmp(*argv,"-auth") == 0)
+			c_auth = 1;
+		else if	(strcmp(*argv,"-auth_require_reneg") == 0)
+			c_auth_require_reneg = 1;
 #endif
 #ifdef WATT32
 		else if (strcmp(*argv,"-wdebug") == 0)
@@ -1399,9 +1429,12 @@
 		}
 
 #endif
-	if (c_proof_debug)
-		SSL_CTX_set_tlsext_authz_server_audit_proof_cb(ctx,
-							       audit_proof_cb);
+	if (c_auth)
+		{
+		SSL_CTX_set_custom_cli_ext(ctx, TLSEXT_TYPE_client_authz, authz_tlsext_generate_cb, authz_tlsext_cb, bio_err);
+		SSL_CTX_set_custom_cli_ext(ctx, TLSEXT_TYPE_server_authz, authz_tlsext_generate_cb, authz_tlsext_cb, bio_err);
+		SSL_CTX_set_cli_supp_data(ctx, TLSEXT_SUPPLEMENTALDATATYPE_authz_data, suppdata_cb, auth_suppdata_generate_cb, bio_err);
+		}
 #endif
 
 	con=SSL_new(ctx);
@@ -2395,26 +2428,76 @@
 	return 1;
 	}
 
-static int audit_proof_cb(SSL *s, void *arg)
+static int authz_tlsext_cb(SSL *s, unsigned short ext_type,
+			   const unsigned char *in,
+			   unsigned short inlen, int *al,
+			   void *arg)
 	{
-	const unsigned char *proof;
-	size_t proof_len;
-	size_t i;
-	SSL_SESSION *sess = SSL_get_session(s);
-
-	proof = SSL_SESSION_get_tlsext_authz_server_audit_proof(sess,
-								&proof_len);
-	if (proof != NULL)
+	if (TLSEXT_TYPE_server_authz == ext_type)
 		{
-		BIO_printf(bio_c_out, "Audit proof: ");
-		for (i = 0; i < proof_len; ++i)
-			BIO_printf(bio_c_out, "%02X", proof[i]);
-		BIO_printf(bio_c_out, "\n");
+		server_provided_server_authz = (memchr(in,
+		TLSEXT_AUTHZDATAFORMAT_dtcp,
+		inlen) != NULL);
 		}
-	else
+
+	if (TLSEXT_TYPE_client_authz == ext_type)
 		{
-		BIO_printf(bio_c_out, "No audit proof found.\n");
+		server_provided_client_authz = (memchr(in,
+		TLSEXT_AUTHZDATAFORMAT_dtcp,
+		inlen) != NULL);
+		}
+
+	return 1;
+	}
+
+static int authz_tlsext_generate_cb(SSL *s, unsigned short ext_type,
+				    const unsigned char **out, unsigned short *outlen,
+				    void *arg)
+	{
+	if (c_auth)
+		{
+		if (!c_auth_require_reneg || (c_auth_require_reneg && SSL_num_renegotiations(s)))
+			{
+			*out = auth_ext_data;
+			*outlen = 1;
+			return 1;
+			}
+		}
+	//no auth extension to send
+	return -1;
+	}
+
+static int suppdata_cb(SSL *s, unsigned short supp_data_type,
+		       const unsigned char *in,
+		       unsigned short inlen, int *al,
+		       void *arg)
+	{
+	if (supp_data_type == TLSEXT_SUPPLEMENTALDATATYPE_authz_data)
+		{
+		most_recent_supplemental_data = in;
+		most_recent_supplemental_data_length = inlen;
 		}
 	return 1;
 	}
+
+static int auth_suppdata_generate_cb(SSL *s, unsigned short supp_data_type,
+				     const unsigned char **out,
+				     unsigned short *outlen, void *arg)
+	{
+	unsigned char *result;
+	if (c_auth && server_provided_client_authz && server_provided_server_authz)
+		{
+		if (!c_auth_require_reneg || (c_auth_require_reneg && SSL_num_renegotiations(s)))
+			{
+			result = OPENSSL_malloc(10);
+			memcpy(result, "5432154321", 10);
+			*out = result;
+			*outlen = 10;
+			return 1;
+			}
+		}
+	//no supplemental data to send
+	return -1;
+	}
+
 #endif