From 71ca9abc2e05de9cf61b135a4699ed3bb97a8969 Mon Sep 17 00:00:00 2001
From: lohhiiccc <96543753+lohhiiccc@users.noreply.github.com>
Date: Thu, 23 Apr 2026 13:53:35 +0200
Subject: [PATCH] feat: set TOS

---
 includes/icmp.h      |  1 +
 sources.mk           |  1 +
 src/socket/set_tos.c | 25 +++++++++++++++++++++++++
 3 files changed, 27 insertions(+)
 create mode 100644 src/socket/set_tos.c

diff --git a/includes/icmp.h b/includes/icmp.h
index 2a11fe9..5c13ff2 100644
--- a/includes/icmp.h
+++ b/includes/icmp.h
@@ -76,6 +76,7 @@ int icmp_error_extract_offending(const icmp_reply_t *reply,
 
 /* Socket options */
 int icmp_set_dont_fragment(icmp_handle_t *h);
+int icmp_set_tos(icmp_handle_t *h, uint8_t tos);
 
 /* Error handling */
 const char *icmp_strerror(const icmp_handle_t *h);
diff --git a/sources.mk b/sources.mk
index a1c402b..d745d49 100644
--- a/sources.mk
+++ b/sources.mk
@@ -9,6 +9,7 @@ SRCS += $(SRC_DIR)/error/should_retry.c
 SRCS += $(SRC_DIR)/socket/create.c
 SRCS += $(SRC_DIR)/socket/configure.c
 SRCS += $(SRC_DIR)/socket/set_dont_fragment.c
+SRCS += $(SRC_DIR)/socket/set_tos.c
 SRCS += $(SRC_DIR)/handle/create.c
 SRCS += $(SRC_DIR)/handle/destroy.c
 SRCS += $(SRC_DIR)/handle/get_fd.c
diff --git a/src/socket/set_tos.c b/src/socket/set_tos.c
new file mode 100644
index 0000000..767016c
--- /dev/null
+++ b/src/socket/set_tos.c
@@ -0,0 +1,25 @@
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <errno.h>
+#include <string.h>
+
+#include "internal/icmp_internal.h"
+
+int
+icmp_set_tos(struct icmp_handle *h, uint8_t tos)
+{
+	int	val;
+	int	saved_errno;
+
+	if (NULL == h)
+		return -1;
+	val = (int)tos;
+	if (0 > setsockopt(h->fd, IPPROTO_IP, IP_TOS, &val, sizeof(val)))
+	{
+		saved_errno = errno;
+		icmp_set_error_fmt(h, ICMP_ERR_SOCKET,
+				"Failed to set TOS: %s", strerror(saved_errno));
+		return -1;
+	}
+	return 0;
+}