git: 56be282bc999 - main - bhyve: net_backends, automatically IFF_UP tap devices

[Bjoern A. Zeeb]

The branch main has been updated by bz:

URL: https://cgit.FreeBSD.org/src/commit/?id=56be282bc999cc05dcd1ccb163b108d54f3ff448

commit 56be282bc999cc05dcd1ccb163b108d54f3ff448
Author:     Bjoern A. Zeeb <bz at FreeBSD.org>
AuthorDate: 2021-07-28 22:53:25 +0000
Commit:     Bjoern A. Zeeb <bz at FreeBSD.org>
CommitDate: 2021-08-01 20:50:53 +0000

    bhyve: net_backends, automatically IFF_UP tap devices
    
    If you want communications with the outside world and tell bhyve to
    create an interfaces then it should be usable as well.
    Rather than relying on the sysctl net.link.tap.up_on_open automatically
    try to IFF_UP the opened tap device.
    
    MFC after:      10 days
    Reviewed by:    markj, grehan
    Differential Revision: https://reviews.freebsd.org/D31342
---
 usr.sbin/bhyve/net_backends.c | 51 +++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 51 insertions(+)

diff --git a/usr.sbin/bhyve/net_backends.c b/usr.sbin/bhyve/net_backends.c
index 30c26aea458b..cb1730fc77df 100644
--- a/usr.sbin/bhyve/net_backends.c
+++ b/usr.sbin/bhyve/net_backends.c
@@ -46,6 +46,9 @@ __FBSDID("$FreeBSD$");
 #include <sys/uio.h>
 
 #include <net/if.h>
+#if defined(INET6) || defined(INET)
+#include <net/if_tap.h>
+#endif
 #include <net/netmap.h>
 #include <net/netmap_virt.h>
 #define NETMAP_WITH_LIBS
@@ -179,6 +182,17 @@ SET_DECLARE(net_backend_set, struct net_backend);
  * The tap backend
  */
 
+#if defined(INET6) || defined(INET)
+const int pf_list[] = {
+#if defined(INET6)
+	PF_INET6,
+#endif
+#if defined(INET)
+	PF_INET,
+#endif
+};
+#endif
+
 struct tap_priv {
 	struct mevent *mevp;
 	/*
@@ -211,6 +225,10 @@ tap_init(struct net_backend *be, const char *devname,
 	struct tap_priv *priv = (struct tap_priv *)be->opaque;
 	char tbuf[80];
 	int opt = 1;
+#if defined(INET6) || defined(INET)
+	struct ifreq ifrq;
+	int i, s;
+#endif
 #ifndef WITHOUT_CAPSICUM
 	cap_rights_t rights;
 #endif
@@ -238,6 +256,39 @@ tap_init(struct net_backend *be, const char *devname,
 		goto error;
 	}
 
+#if defined(INET6) || defined(INET)
+	/*
+	 * Try to UP the interface rather than relying on
+	 * net.link.tap.up_on_open.
+	  */
+	bzero(&ifrq, sizeof(ifrq));
+	if (ioctl(be->fd, TAPGIFNAME, &ifrq) < 0) {
+		WPRINTF(("Could not get interface name"));
+		goto error;
+	}
+
+	s = -1;
+	for (i = 0; s == -1 && i < nitems(pf_list); i++)
+		s = socket(pf_list[i], SOCK_DGRAM, 0);
+	if (s == -1) {
+		WPRINTF(("Could open socket"));
+		goto error;
+	}
+
+	if (ioctl(s, SIOCGIFFLAGS, &ifrq) < 0) {
+		(void)close(s);
+		WPRINTF(("Could not get interface flags"));
+		goto error;
+	}
+	ifrq.ifr_flags |= IFF_UP;
+	if (ioctl(s, SIOCSIFFLAGS, &ifrq) < 0) {
+		(void)close(s);
+		WPRINTF(("Could not set interface flags"));
+		goto error;
+	}
+	(void)close(s);
+#endif
+
 #ifndef WITHOUT_CAPSICUM
 	cap_rights_init(&rights, CAP_EVENT, CAP_READ, CAP_WRITE);
 	if (caph_rights_limit(be->fd, &rights) == -1)