From 2864c3d15499ac133b4fffbc27787671c11939d5 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Petr=20=C5=A0tetiar?= <ynezz@true.cz>
Date: Fri, 26 Aug 2022 09:10:54 +0200
Subject: [PATCH] Make IP Type-Of-Service feature optional
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Add new -z commandline option which when set, disables new IP TOS
feature.

References: https://github.com/openwrt/openwrt/issues/10405
Signed-off-by: Petr Štetiar <ynezz@true.cz>
---
 cli-runopts.c | 4 ++++
 netio.c       | 3 +++
 runopts.h     | 1 +
 svr-runopts.c | 5 +++++
 4 files changed, 13 insertions(+)

diff --git a/cli-runopts.c b/cli-runopts.c
index 8df1b7a..07fce1b 100644
--- a/cli-runopts.c
+++ b/cli-runopts.c
@@ -98,6 +98,7 @@ static void printhelp() {
 #if DEBUG_TRACE
 					"-v    verbose (repeat for more verbose)\n"
 #endif
+					"-z    disable IP Type-Of-Service feature\n"
 					,DROPBEAR_VERSION, cli_opts.progname,
 #if DROPBEAR_CLI_PUBKEY_AUTH
 					DROPBEAR_DEFAULT_CLI_AUTHKEY,
@@ -325,6 +326,9 @@ void cli_getopts(int argc, char ** argv) {
 				case 'b':
 					next = &bind_arg;
 					break;
+				case 'z':
+					opts.disable_ip_tos = 1;
+					break;
 				default:
 					fprintf(stderr,
 						"WARNING: Ignoring unknown option -%c\n", c);
diff --git a/netio.c b/netio.c
index 2ed9bb1..b8aebea 100644
--- a/netio.c
+++ b/netio.c
@@ -3,6 +3,7 @@
 #include "dbutil.h"
 #include "session.h"
 #include "debug.h"
+#include "runopts.h"
 
 struct dropbear_progress_connection {
 	struct addrinfo *res;
@@ -377,6 +378,7 @@ void set_sock_priority(int sock, enum dropbear_prio prio) {
 	/* Don't log ENOTSOCK errors so that this can harmlessly be called
 	 * on a client '-J' proxy pipe */
 
+	if (opts.disable_ip_tos == 0) {
 #ifdef IP_TOS
 	/* Set the DSCP field for outbound IP packet priority.
 	rfc4594 has some guidance to meanings.
@@ -409,6 +411,7 @@ void set_sock_priority(int sock, enum dropbear_prio prio) {
 		TRACE(("Couldn't set IP_TOS (%s)", strerror(errno)));
 	}
 #endif /* IP_TOS */
+	}
 
 #ifdef HAVE_LINUX_PKT_SCHED_H
 	/* Set scheduling priority within the local Linux network stack */
diff --git a/runopts.h b/runopts.h
index 48a768c..1675836 100644
--- a/runopts.h
+++ b/runopts.h
@@ -33,6 +33,7 @@
 
 typedef struct runopts {
 
+	int disable_ip_tos;
 #if DROPBEAR_SVR_REMOTETCPFWD || DROPBEAR_CLI_LOCALTCPFWD \
     || DROPBEAR_CLI_REMOTETCPFWD
 	int listen_fwd_all;
diff --git a/svr-runopts.c b/svr-runopts.c
index 7b76dca..aae4ca1 100644
--- a/svr-runopts.c
+++ b/svr-runopts.c
@@ -112,6 +112,7 @@ static void printhelp(const char * progname) {
 #if DEBUG_TRACE
 					"-v    verbose (repeat for more verbose)\n"
 #endif
+					"-z		disable IP Type-Of-Service feature\n"
 					,DROPBEAR_VERSION, progname,
 #if DROPBEAR_DSS
 					DSS_PRIV_FILENAME,
@@ -201,6 +202,7 @@ void svr_getopts(int argc, char ** argv) {
 #if DROPBEAR_SVR_REMOTETCPFWD
 	opts.listen_fwd_all = 0;
 #endif
+	opts.disable_ip_tos = 0;
 
 	for (i = 1; i < (unsigned int)argc; i++) {
 		if (argv[i][0] != '-' || argv[i][1] == '\0')
@@ -324,6 +326,9 @@ void svr_getopts(int argc, char ** argv) {
 					print_version();
 					exit(EXIT_SUCCESS);
 					break;
+				case 'z':
+					opts.disable_ip_tos = 1;
+					break;
 				default:
 					fprintf(stderr, "Invalid option -%c\n", c);
 					printhelp(argv[0]);