bgpd: Allow bgp to specify if it will allow v6 routing with v4 nexthops

Add a `--v6-with-v4-nexthop` cli to bgp to allow it to peer with
neighbors in the configuration where the interface has no v6 addresses
at all and there is a v4 address that is usable as a v4 address
embedded in a v6 address.

Signed-off-by: Donald Sharp <sharpd@nvidia.com>

1 files changed, 24 insertions, 19 deletions

diff --git a/bgpd/bgp_main.c b/bgpd/bgp_main.c
index 074059c146..11917c6c4a 100644
--- a/bgpd/bgp_main.c
+++ b/bgpd/bgp_main.c
@@ -57,15 +57,17 @@
 
 /* bgpd options, we use GNU getopt library. */
 static const struct option longopts[] = {
-	{"bgp_port", required_argument, NULL, 'p'},
-	{"listenon", required_argument, NULL, 'l'},
-	{"no_kernel", no_argument, NULL, 'n'},
-	{"skip_runas", no_argument, NULL, 'S'},
-	{"ecmp", required_argument, NULL, 'e'},
-	{"int_num", required_argument, NULL, 'I'},
-	{"no_zebra", no_argument, NULL, 'Z'},
-	{"socket_size", required_argument, NULL, 's'},
-	{0}};
+	{ "bgp_port", required_argument, NULL, 'p' },
+	{ "listenon", required_argument, NULL, 'l' },
+	{ "no_kernel", no_argument, NULL, 'n' },
+	{ "skip_runas", no_argument, NULL, 'S' },
+	{ "ecmp", required_argument, NULL, 'e' },
+	{ "int_num", required_argument, NULL, 'I' },
+	{ "no_zebra", no_argument, NULL, 'Z' },
+	{ "socket_size", required_argument, NULL, 's' },
+	{ "v6-with-v4-nexthops", no_argument, NULL, 'v' },
+	{ 0 }
+};
 
 /* signal definitions */
 void sighup(void);
@@ -387,16 +389,16 @@ int main(int argc, char **argv)
 	addresses->cmp = (int (*)(void *, void *))strcmp;
 
 	frr_preinit(&bgpd_di, argc, argv);
-	frr_opt_add(
-		"p:l:SnZe:I:s:" DEPRECATED_OPTIONS, longopts,
-		"  -p, --bgp_port     Set BGP listen port number (0 means do not listen).\n"
-		"  -l, --listenon     Listen on specified address (implies -n)\n"
-		"  -n, --no_kernel    Do not install route to kernel.\n"
-		"  -Z, --no_zebra     Do not communicate with Zebra.\n"
-		"  -S, --skip_runas   Skip capabilities checks, and changing user and group IDs.\n"
-		"  -e, --ecmp         Specify ECMP to use.\n"
-		"  -I, --int_num      Set instance number (label-manager)\n"
-		"  -s, --socket_size  Set BGP peer socket send buffer size\n");
+	frr_opt_add("p:l:SnZe:I:s:" DEPRECATED_OPTIONS, longopts,
+		    "  -p, --bgp_port           Set BGP listen port number (0 means do not listen).\n"
+		    "  -l, --listenon           Listen on specified address (implies -n)\n"
+		    "  -n, --no_kernel          Do not install route to kernel.\n"
+		    "  -Z, --no_zebra           Do not communicate with Zebra.\n"
+		    "  -S, --skip_runas         Skip capabilities checks, and changing user and group IDs.\n"
+		    "  -e, --ecmp               Specify ECMP to use.\n"
+		    "  -I, --int_num            Set instance number (label-manager)\n"
+		    "  -s, --socket_size        Set BGP peer socket send buffer size\n"
+		    "    , --v6-with-v4-nexthop Allow BGP to form v6 neighbors using v4 nexthops\n");
 
 	/* Command line argument treatment. */
 	while (1) {
@@ -458,6 +460,9 @@ int main(int argc, char **argv)
 		case 's':
 			buffer_size = atoi(optarg);
 			break;
+		case 'v':
+			bm->v6_with_v4_nexthops = true;
+			break;
 		default:
 			frr_help_exit(1);
 		}