From 073a59264a4284a53ebad56d7e273f022a43dff7 Mon Sep 17 00:00:00 2001
From: Andy Green <andy@warmcat.com>
Date: Fri, 15 May 2020 18:21:56 +0100
Subject: [PATCH] unix domain: fix path name length

Unlike any other sockaddr variant it turns out when sockaddr_un reports its
sizeof() to connect() or listen(), it is trimmed to the used length of the
sun_path[] member not including any trailing 0x00.

Until now we worked fine, but our actual UDS paths have a large number of
trailing 0x00 (shown as @ in most tools).  Clients and servers can still
interoperate if they both have this broken name.

This patch fixes it to trim the sockaddr_un to the path length so the name
is as you would expect.
---
 CMakeLists.txt                           | 2 +-
 lib/core-net/network.c                   | 4 +++-
 lib/roles/http/client/client-handshake.c | 5 ++++-
 3 files changed, 8 insertions(+), 3 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index fdd17729e..efadb52a7 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -327,7 +327,7 @@ set(PACKAGE "libwebsockets")
 set(CPACK_PACKAGE_NAME "${PACKAGE}")
 set(CPACK_PACKAGE_VERSION_MAJOR "4")
 set(CPACK_PACKAGE_VERSION_MINOR "0")
-set(CPACK_PACKAGE_VERSION_PATCH "9")
+set(CPACK_PACKAGE_VERSION_PATCH "10")
 set(CPACK_PACKAGE_RELEASE 1)
 set(CPACK_GENERATOR "RPM")
 set(CPACK_PACKAGE_VERSION "${CPACK_PACKAGE_VERSION_MAJOR}.${CPACK_PACKAGE_VERSION_MINOR}.${CPACK_PACKAGE_VERSION_PATCH}")
diff --git a/lib/core-net/network.c b/lib/core-net/network.c
index 99e561995..c5340baa2 100644
--- a/lib/core-net/network.c
+++ b/lib/core-net/network.c
@@ -215,7 +215,6 @@ lws_socket_bind(struct lws_vhost *vhost, lws_sockfd_type sockfd, int port,
 #if defined(LWS_WITH_UNIX_SOCK)
 	if (!port && LWS_UNIX_SOCK_ENABLED(vhost)) {
 		v = (struct sockaddr *)&serv_unix;
-		n = sizeof(struct sockaddr_un);
 		memset(&serv_unix, 0, sizeof(serv_unix));
 		serv_unix.sun_family = AF_UNIX;
 		if (!iface)
@@ -225,12 +224,15 @@ lws_socket_bind(struct lws_vhost *vhost, lws_sockfd_type sockfd, int port,
 			         iface);
 			return LWS_ITOSA_NOT_EXIST;
 		}
+		n = sizeof(uint16_t) + strlen(iface);
 		strcpy(serv_unix.sun_path, iface);
 		if (serv_unix.sun_path[0] == '@')
 			serv_unix.sun_path[0] = '\0';
 		else
 			unlink(serv_unix.sun_path);
 
+		//lwsl_hexdump_notice(v, n);
+
 	} else
 #endif
 #if defined(LWS_WITH_IPV6) && !defined(LWS_PLAT_FREERTOS)
diff --git a/lib/roles/http/client/client-handshake.c b/lib/roles/http/client/client-handshake.c
index c5867178f..cfca321e3 100644
--- a/lib/roles/http/client/client-handshake.c
+++ b/lib/roles/http/client/client-handshake.c
@@ -644,7 +644,10 @@ ads_known:
 #if defined(LWS_WITH_UNIX_SOCK)
 	if (wsi->unix_skt) {
 		psa = (const struct sockaddr *)&sau;
-		n = sizeof(sau);
+		if (sau.sun_path[0])
+			n = sizeof(uint16_t) + strlen(sau.sun_path);
+		else
+			n = sizeof(uint16_t) + strlen(&sau.sun_path[1]) + 1;
 	} else
 #endif