From 47dd026ce3a9b726d1613586b8923db2c1afd645 Mon Sep 17 00:00:00 2001
From: flu0r1ne <flu0r1ne@flu0r1ne.net>
Date: Tue, 3 Oct 2023 22:13:00 -0500
Subject: [PATCH 1/3] Use a uint32 for the type of a Linux mark

It is typical to store and manipulate Linux packet marks using unsigned values.
---
 packet/probe.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/packet/probe.h b/packet/probe.h
index caf1314b..5a5dc3af 100644
--- a/packet/probe.h
+++ b/packet/probe.h
@@ -69,7 +69,7 @@ struct probe_param_t {
     int type_of_service;
 
     /*  The packet "mark" used for mark-based routing on Linux  */
-    int routing_mark;
+    uint32_t routing_mark;
 
     /*  Time to live for the transmitted probe  */
     int ttl;

From 23486b312c0dd9c147799d5f312c0b9ac015eec3 Mon Sep 17 00:00:00 2001
From: flu0r1ne <flu0r1ne@flu0r1ne.net>
Date: Tue, 3 Oct 2023 22:31:23 -0500
Subject: [PATCH 2/3] Use Packet Marking for IP Address Selection

In certain scenarios, the routing policy database may affect packet
routing. When selecting an address in `mtr`, assign a packet mark if
`SO_MARK` is defined and a mark has been supplied.
---
 ui/net.c | 15 ++++++++++++---
 1 file changed, 12 insertions(+), 3 deletions(-)

diff --git a/ui/net.c b/ui/net.c
index efeb7822..45c33ec8 100644
--- a/ui/net.c
+++ b/ui/net.c
@@ -687,8 +687,8 @@ static void net_find_interface_address_from_name(
   host by connecting a UDP socket and checking the address
   the socket is bound to.
 */
-static void net_find_local_address(
-    void)
+static
+void net_find_local_address(struct mtr_ctl * ctl)
 {
     int udp_socket;
     int addr_length;
@@ -700,6 +700,15 @@ static void net_find_local_address(
         error(EXIT_FAILURE, errno, "udp socket creation failed");
     }
 
+#ifdef SO_MARK
+    /* On Linux, the packet mark can affect the selection of the source address */
+    if(ctl->mark) {
+        if(setsockopt(udp_socket, SOL_SOCKET, SO_MARK, &ctl->mark, sizeof(ctl->mark))) {
+            error(EXIT_FAILURE, errno, "failed to set the packet mark");
+        }
+    }
+#endif
+
     /*
        We need to set the port to a non-zero value for the connect
        to succeed.
@@ -778,7 +787,7 @@ void net_reopen(
             &sourcesockaddr_struct, ctl->af, ctl->InterfaceName);
         inet_ntop(sourcesockaddr->sa_family, sourceaddress, localaddr, sizeof(localaddr));
     } else {
-        net_find_local_address();
+        net_find_local_address(ctl);
     }
 
 }

From 7d8b704e8d6d7ea40919659a763a64d43c416725 Mon Sep 17 00:00:00 2001
From: flu0r1ne <flu0r1ne@flu0r1ne.net>
Date: Tue, 3 Oct 2023 22:45:20 -0500
Subject: [PATCH 3/3] Support Hexadecimal Arguments for Packet Marking

Packet marks are often specified in hexadecimal format. Update the
`strtonum_or_err` function to parse both hexadecimal and decimal
values.
---
 ui/utils.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/ui/utils.c b/ui/utils.c
index edd59055..5e3a701c 100644
--- a/ui/utils.c
+++ b/ui/utils.c
@@ -80,7 +80,7 @@ int strtonum_or_err(
 
     if (str != NULL && *str != '\0') {
         errno = 0;
-        num = strtoul(str, &end, 10);
+        num = strtoul(str, &end, 0);
         if (errno == 0 && str != end && end != NULL && *end == '\0') {
             switch (type) {
             case STRTO_INT: