From 0ac498d7d37fa27032021b193ab0a9d7ae17f227 Mon Sep 17 00:00:00 2001
From: Samuel Thibault <samuel.thibault@ens-lyon.org>
Date: Thu, 18 Jan 2024 02:00:21 +0100
Subject: [PATCH] cli: Show acceleration interface name

And allow selecting a session through it
---
 cli.c    | 17 ++++++++++++++++-
 l2tpns.c |  6 ++++--
 l2tpns.h |  6 +++++-
 3 files changed, 25 insertions(+), 4 deletions(-)

diff --git a/cli.c b/cli.c
index b0049ac..e3cea88 100644
--- a/cli.c
+++ b/cli.c
@@ -451,10 +451,23 @@ static int cmd_show_session(struct cli_def *cli, const char *command, char **arg
 		for (i = 0; i < argc; i++)
 		{
 			unsigned int s, b_in, b_out, r;
+			int ifunit = -1;
+
+			if (!strncmp(argv[i], PPP_IF_PREFIX, strlen(PPP_IF_PREFIX)))
+			{
+				char *start = argv[i]+strlen(PPP_IF_PREFIX);
+				char *end;
+				long res = strtol(start, &end, 10);
+				if (end != start && !*end)
+					ifunit = res;
+			}
 
 			for (s = 0; s < MAXSESSION; s++)
-				if (!strcmp(argv[i], session[s].user))
+			{
+				if ((ifunit >= 0 && sess_local[s].ppp_if_unit == ifunit)
+					|| !strcmp(argv[i], session[s].user))
 					break;
+			}
 			if (s >= MAXSESSION)
 			{
 				s = atoi(argv[i]);
@@ -473,6 +486,8 @@ static int cmd_show_session(struct cli_def *cli, const char *command, char **arg
 			cli_print(cli, "\tRemote ID:\t%d", session[s].far);
 			if (session[s].bundle)
 				cli_print(cli, "\tBundle ID:\t%d (%d)", session[s].bundle, bundle[session[s].bundle].num_of_links);
+			if (sess_local[s].ppp_if_unit >= 0)
+				cli_print(cli, "\tInterface:\tppp%d", sess_local[s].ppp_if_unit);
 			cli_print(cli, "\tPPP Phase:\t%s", ppp_phase(session[s].ppp.phase));
 			switch (session[s].ppp.phase)
 			{
diff --git a/l2tpns.c b/l2tpns.c
index 34afaf7..378e6fe 100644
--- a/l2tpns.c
+++ b/l2tpns.c
@@ -49,8 +49,6 @@
 #define PPPIOCUNBRIDGECHAN _IO('t', 54)
 #endif
 
-#define PPP_IF_PREFIX "ppp"
-
 #include "md5.h"
 #include "dhcp6.h"
 #include "l2tpns.h"
@@ -1228,6 +1226,7 @@ static int create_kernel_accel(sessionidt s)
 	sess_local[s].pppox_fd = pppox_fd;
 	sess_local[s].ppp_chan_fd = ppp_chan_fd;
 	sess_local[s].ppp_if_fd = ppp_if_fd;
+	sess_local[s].ppp_if_unit = ifunit;
 	sess_local[s].ppp_if_idx = ifr.ifr_ifindex;
 
 	dhcpv6_listen(ifr.ifr_ifindex);
@@ -1256,6 +1255,7 @@ static int delete_kernel_accel(sessionidt s)
 
 	LOG(3, s, session[s].tunnel, "Stopping kernel-accelerated support for %u:%u\n", session[s].tunnel, s);
 
+	sess_local[s].ppp_if_unit = -1;
 	sess_local[s].ppp_if_idx = 0;
 
 	ioctl(sess_local[s].ppp_chan_fd, PPPIOCDISCONN);
@@ -3666,6 +3666,7 @@ static void sessionclear(sessionidt s)
 	sess_local[s].pppox_fd = -1;
 	sess_local[s].ppp_chan_fd = -1;
 	sess_local[s].ppp_if_fd = -1;
+	sess_local[s].ppp_if_unit = -1;
 	memset(&cli_session_actions[s], 0, sizeof(cli_session_actions[s]));
 
 	session[s].tunnel = T_FREE;	// Mark it as free.
@@ -6229,6 +6230,7 @@ static void initdata(int optdebug, char *optconfig)
 		sess_local[i].pppox_fd = -1;
 		sess_local[i].ppp_chan_fd = -1;
 		sess_local[i].ppp_if_fd = -1;
+		sess_local[i].ppp_if_unit = -1;
 	}
 	session[MAXSESSION - 1].next = 0;
 	sessionfree = 1;
diff --git a/l2tpns.h b/l2tpns.h
index 8b5468f..33e9f9a 100644
--- a/l2tpns.h
+++ b/l2tpns.h
@@ -31,6 +31,8 @@
 // Tunnel Id reserved for pppoe
 #define TUNNEL_ID_PPPOE	1
 
+#define PPP_IF_PREFIX "ppp"
+
 #define RADIUS_SHIFT	6
 #define RADIUS_FDS	(1 << RADIUS_SHIFT)
 #define RADIUS_MASK	((1 << RADIUS_SHIFT) - 1)
@@ -459,7 +461,9 @@ typedef struct
 
 	// ppp interface
 	int ppp_if_fd;
-	// ppp interface index
+	// ppp interface number (ppp%d)
+	int ppp_if_unit;
+	// ppp interface index (for rtnetlink etc.)
 	int ppp_if_idx;
 } sessionlocalt;