Merge branch 'wip/dueno/cert-compression-followup' into 'master'

compress-cert: support compression of client certificates

Closes #1397

See merge request gnutls/gnutls!1641

6 files changed, 274 insertions, 4 deletions

diff --git a/.gitignore b/.gitignore
index 821fc85f1d..4225452b8d 100644
--- a/.gitignore
+++ b/.gitignore
@@ -864,6 +864,7 @@ tests/tls13-without-timeout-func
 tests/tls13/anti_replay
 tests/tls13/change_cipher_spec
 tests/tls13/compress-cert
+tests/tls13/compress-cert-cli
 tests/tls13/compress-cert-neg
 tests/tls13/compress-cert-neg2
 tests/tls13/cookie
diff --git a/lib/ext/compress_certificate.c b/lib/ext/compress_certificate.c
index 8144368faa..8f8d75c9ad 100644
--- a/lib/ext/compress_certificate.c
+++ b/lib/ext/compress_certificate.c
@@ -161,7 +161,7 @@ gnutls_compress_certificate_set_methods(gnutls_session_t session,
 	return 0;
 }
 
-static int
+int
 _gnutls_compress_certificate_recv_params(gnutls_session_t session,
 					 const uint8_t * data,
 					 size_t data_size)
@@ -209,7 +209,7 @@ endloop:
 	return 0;
 }
 
-static int
+int
 _gnutls_compress_certificate_send_params(gnutls_session_t session,
 					 gnutls_buffer_st * data)
 {
@@ -245,7 +245,7 @@ const hello_ext_entry_st ext_mod_compress_certificate = {
 	.client_parse_point = GNUTLS_EXT_TLS,
 	.server_parse_point = GNUTLS_EXT_TLS,
 	.validity = GNUTLS_EXT_FLAG_TLS | GNUTLS_EXT_FLAG_DTLS | 
-		    GNUTLS_EXT_FLAG_CLIENT_HELLO | GNUTLS_EXT_FLAG_TLS13_SERVER_HELLO,
+		    GNUTLS_EXT_FLAG_CLIENT_HELLO,
 	.recv_func = _gnutls_compress_certificate_recv_params,
 	.send_func = _gnutls_compress_certificate_send_params,
 	.deinit_func = _gnutls_hello_ext_default_deinit
diff --git a/lib/ext/compress_certificate.h b/lib/ext/compress_certificate.h
index 88199da187..b7083742ef 100644
--- a/lib/ext/compress_certificate.h
+++ b/lib/ext/compress_certificate.h
@@ -38,4 +38,12 @@ extern const hello_ext_entry_st ext_mod_compress_certificate;
 gnutls_compression_method_t _gnutls_compress_certificate_num2method(uint16_t num);
 int _gnutls_compress_certificate_method2num(gnutls_compression_method_t method);
 
+int
+_gnutls_compress_certificate_recv_params(gnutls_session_t session,
+					 const uint8_t * data,
+					 size_t data_size);
+int
+_gnutls_compress_certificate_send_params(gnutls_session_t session,
+					 gnutls_buffer_st * data);
+
 #endif /* GNUTLS_LIB_EXT_COMPRESS_CERTIFICATE_H */
diff --git a/lib/tls13/certificate_request.c b/lib/tls13/certificate_request.c
index 37e7b41049..b613cab13f 100644
--- a/lib/tls13/certificate_request.c
+++ b/lib/tls13/certificate_request.c
@@ -25,6 +25,7 @@
 #include "extv.h"
 #include "handshake.h"
 #include "tls13/certificate_request.h"
+#include "ext/compress_certificate.h"
 #include "ext/signature.h"
 #include "ext/status_request.h"
 #include "mbuffers.h"
@@ -128,6 +129,13 @@ int parse_cert_extension(void *_ctx, unsigned tls_id, const uint8_t *data, unsig
 
 		ctx->rdn = data+2;
 		ctx->rdn_size = v;
+	} else if (tls_id == ext_mod_compress_certificate.tls_id) {
+		ret = _gnutls_compress_certificate_recv_params(session,
+							       data,
+							       data_size);
+		if (ret < 0) {
+			return gnutls_assert_val(ret);
+		}
 	}
 
 	return 0;
@@ -357,6 +365,13 @@ int _gnutls13_send_certificate_request(gnutls_session_t session, unsigned again)
 		session->internals.hsk_flags |= HSK_CLIENT_OCSP_REQUESTED;
 #endif
 
+		ret = _gnutls_extv_append(&buf, ext_mod_compress_certificate.tls_id, session,
+					  (extv_append_func)_gnutls_compress_certificate_send_params);
+		if (ret < 0) {
+			gnutls_assert();
+			goto cleanup;
+		}
+
 		ret = _gnutls_extv_append_final(&buf, init_pos, 0);
 		if (ret < 0) {
 			gnutls_assert();
diff --git a/tests/Makefile.am b/tests/Makefile.am
index acc2b86404..3e126f0046 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -122,7 +122,7 @@ ctests = tls13/supported_versions tls13/tls12-no-tls13-exts \
 	tls12-check-rollback-val tls11-check-rollback-val \
 	tls13/post-handshake-with-psk tls13/post-handshake-with-cert-auto \
 	tls13/anti_replay tls13/compress-cert tls13/compress-cert-neg \
-	tls13/compress-cert-neg2
+	tls13/compress-cert-neg2 tls13/compress-cert-cli
 
 ctests += tls13/hello_retry_request
 
diff --git a/tests/tls13/compress-cert-cli.c b/tests/tls13/compress-cert-cli.c
new file mode 100644
index 0000000000..f4e66bf313
--- /dev/null
+++ b/tests/tls13/compress-cert-cli.c
@@ -0,0 +1,246 @@
+/*
+ * Copyright (C) 2022 Red Hat, Inc.
+ *
+ * Author: Daiki Ueno
+ *
+ * This file is part of GnuTLS.
+ *
+ * GnuTLS is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * GnuTLS is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>
+ */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <stdbool.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <errno.h>
+#include <gnutls/gnutls.h>
+#include <gnutls/crypto.h>
+#include <assert.h>
+#include "cert-common.h"
+
+#include "utils.h"
+#include "eagain-common.h"
+
+const char *side = "";
+
+static void tls_log_func(int level, const char *str)
+{
+	fprintf(stderr, "%s|<%d>| %s", side, level, str);
+}
+
+struct handshake_cb_data_st {
+	bool is_server;
+	bool found_compress_certificate;
+	bool found_compressed_certificate;
+	bool found_certificate;
+};
+
+static int ext_callback(void *ctx, unsigned tls_id, const unsigned char *data, unsigned size)
+{
+	struct handshake_cb_data_st *cb_data = ctx;
+	if (tls_id == 27) {	/* compress_certificate */
+		cb_data->found_compress_certificate = 1;
+	}
+	return 0;
+}
+
+#define SKIP8(pos, total) { \
+	uint8_t _s; \
+	if (pos+1 > total) fail("error\n"); \
+	_s = msg->data[pos]; \
+	if ((size_t)(pos+1+_s) > total) fail("error\n"); \
+	pos += 1+_s; \
+	}
+
+static int
+handshake_callback(gnutls_session_t session, unsigned int htype,
+		   unsigned post, unsigned int incoming,
+		   const gnutls_datum_t *msg)
+{
+	struct handshake_cb_data_st *data = gnutls_session_get_ptr(session);
+	unsigned pos = 0;
+	gnutls_datum_t mmsg;
+	int ret;
+
+	if ((data->is_server && incoming) ||
+	    (!data->is_server && !incoming)) {
+		return 0;
+	}
+
+	switch (htype) {
+	case GNUTLS_HANDSHAKE_CERTIFICATE_REQUEST:
+		SKIP8(pos, msg->size);
+
+		mmsg.data = &msg->data[pos];
+		mmsg.size = msg->size - pos;
+		ret = gnutls_ext_raw_parse(data, ext_callback, &mmsg, 0);
+		assert(ret >= 0);
+		break;
+	case GNUTLS_HANDSHAKE_COMPRESSED_CERTIFICATE_PKT:
+		data->found_compressed_certificate = true;
+		break;
+	case GNUTLS_HANDSHAKE_CERTIFICATE_PKT:
+		data->found_certificate = true;
+		break;
+	default:
+		break;
+	}
+
+	return 0;
+}
+
+static void run(void)
+{
+	/* Server stuff. */
+	gnutls_certificate_credentials_t scred;
+	gnutls_session_t server;
+	gnutls_compression_method_t smethods[] = {
+		GNUTLS_COMP_ZSTD, GNUTLS_COMP_BROTLI, GNUTLS_COMP_ZLIB
+	};
+	struct handshake_cb_data_st sdata = { 0, false, false, false };
+	int sret;
+	/* Client stuff. */
+	gnutls_certificate_credentials_t ccred;
+	gnutls_session_t client;
+	gnutls_compression_method_t cmethods[] = {
+		GNUTLS_COMP_ZLIB, GNUTLS_COMP_BROTLI
+	};
+	struct handshake_cb_data_st cdata = { 0, false, false, false };
+	int cret;
+	/* Need to enable anonymous KX specifically. */
+	int ret;
+
+	/* General init. */
+	global_init();
+	gnutls_global_set_log_function(tls_log_func);
+	if (debug)
+		gnutls_global_set_log_level(9);
+
+	/* Init server */
+	assert(gnutls_certificate_allocate_credentials(&scred) >= 0);
+	assert(gnutls_certificate_set_x509_key_mem(scred,
+						   &server_ca3_localhost_cert,
+						   &server_ca3_key,
+						   GNUTLS_X509_FMT_PEM) >= 0);
+	assert(gnutls_certificate_set_x509_trust_mem(scred,
+						     &ca3_cert,
+						     GNUTLS_X509_FMT_PEM) >= 0);
+
+	assert(gnutls_init(&server, GNUTLS_SERVER) >= 0);
+	gnutls_certificate_server_set_request(server, GNUTLS_CERT_REQUEST);
+	ret =
+	    gnutls_priority_set_direct(server,
+				       "NORMAL:-VERS-TLS-ALL:+VERS-TLS1.3",
+				       NULL);
+	if (ret < 0)
+		exit(1);
+
+	ret = gnutls_compress_certificate_set_methods(server, smethods, sizeof(smethods)/sizeof(*smethods));
+	if (ret < 0) {
+		fail("server: setting compression method failed (%s)\n",
+		     gnutls_strerror(ret));
+	}
+	sdata.is_server = true;
+	gnutls_session_set_ptr(server, &sdata);
+	gnutls_handshake_set_hook_function(server, GNUTLS_HANDSHAKE_ANY,
+					   GNUTLS_HOOK_POST,
+					   handshake_callback);
+
+	gnutls_credentials_set(server, GNUTLS_CRD_CERTIFICATE, scred);
+	gnutls_transport_set_push_function(server, server_push);
+	gnutls_transport_set_pull_function(server, server_pull);
+	gnutls_transport_set_ptr(server, server);
+
+	/* Init client */
+	assert(gnutls_certificate_allocate_credentials(&ccred) >= 0);
+	assert(gnutls_certificate_set_x509_key_mem
+	       (ccred, &cli_ca3_cert_chain, &cli_ca3_key, GNUTLS_X509_FMT_PEM) >= 0);
+	assert(gnutls_certificate_set_x509_trust_mem
+	       (ccred, &ca3_cert, GNUTLS_X509_FMT_PEM) >= 0);
+
+	gnutls_init(&client, GNUTLS_CLIENT);
+	ret =
+	    gnutls_priority_set_direct(client,
+				       "NORMAL:-VERS-TLS-ALL:+VERS-TLS1.3",
+				       NULL);
+	assert(ret >= 0);
+
+	ret = gnutls_credentials_set(client, GNUTLS_CRD_CERTIFICATE, ccred);
+	if (ret < 0)
+		exit(1);
+
+	ret = gnutls_compress_certificate_set_methods(client, cmethods, sizeof(cmethods)/sizeof(*cmethods));
+	if (ret < 0) {
+		fail("client: setting compression method failed (%s)\n",
+		     gnutls_strerror(ret));
+	}
+	cdata.is_server = false;
+	gnutls_session_set_ptr(client, &cdata);
+	gnutls_handshake_set_hook_function(client, GNUTLS_HANDSHAKE_ANY,
+					   GNUTLS_HOOK_POST,
+					   handshake_callback);
+
+	gnutls_transport_set_push_function(client, client_push);
+	gnutls_transport_set_pull_function(client, client_pull);
+	gnutls_transport_set_ptr(client, client);
+
+
+	HANDSHAKE(client, server);
+	if (debug)
+		success("Handshake established\n");
+
+	if (!sdata.found_compress_certificate) {
+		fail("server: compress_certificate extension not sent\n");
+	}
+	if (!sdata.found_compressed_certificate) {
+		fail("server: CompressedCertificate not sent\n");
+	}
+	if (sdata.found_certificate) {
+		fail("server: Certificate sent\n");
+	}
+	if (!cdata.found_compress_certificate) {
+		fail("client: compress_certificate extension not received\n");
+	}
+	if (!cdata.found_compressed_certificate) {
+		fail("client: CompressedCertificate not received\n");
+	}
+	if (cdata.found_certificate) {
+		fail("client: Certificate not received\n");
+	}
+
+	gnutls_bye(client, GNUTLS_SHUT_WR);
+	gnutls_bye(server, GNUTLS_SHUT_WR);
+
+	gnutls_deinit(client);
+	gnutls_deinit(server);
+
+	gnutls_certificate_free_credentials(scred);
+	gnutls_certificate_free_credentials(ccred);
+
+	gnutls_global_deinit();
+	reset_buffers();
+}
+
+void doit(void)
+{
+#if !defined(HAVE_LIBZ) || !defined(HAVE_LIBBROTLI) || !defined(HAVE_LIBZSTD)
+	exit(77);
+#endif
+	run();
+}