From: Ben Pfaff <blp@nicira.com>
Date: Mon, 6 Jul 2009 18:02:57 +0000 (-0700)
Subject: dpif-linux: Don't allow arbitrary internal ports to identify a datapath.
X-Git-Url: https://pintos-os.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=a165b67e53a835c623c13de4a0df5f4d7bc9db25;p=openvswitch

dpif-linux: Don't allow arbitrary internal ports to identify a datapath.

The userspace tools were allowing the name of any internal port to be used
to identify a datapath.  This, however, makes it hard to enumerate all the
names by which a datapath can be known, and it was never documented or
intentional behavior, so this commit disables it.
---

diff --git a/datapath/dp_dev.c b/datapath/dp_dev.c
index 34a102a3..848a27b2 100644
--- a/datapath/dp_dev.c
+++ b/datapath/dp_dev.c
@@ -124,7 +124,7 @@ static void dp_getinfo(struct net_device *netdev, struct ethtool_drvinfo *info)
 {
 	struct dp_dev *dp_dev = dp_dev_priv(netdev);
 	strcpy(info->driver, "openvswitch");
-	sprintf(info->bus_info, "%d", dp_dev->dp->dp_idx);
+	sprintf(info->bus_info, "%d.%d", dp_dev->dp->dp_idx, dp_dev->port_no);
 }
 
 static struct ethtool_ops dp_ethtool_ops = {
diff --git a/lib/dpif-linux.c b/lib/dpif-linux.c
index 417349d8..8cc213d5 100644
--- a/lib/dpif-linux.c
+++ b/lib/dpif-linux.c
@@ -453,9 +453,10 @@ do_ioctl(const struct dpif *dpif_, int cmd, const void *arg)
 }
 
 static int
-lookup_minor(const char *name, int *minor)
+lookup_minor(const char *name, int *minorp)
 {
     struct ethtool_drvinfo drvinfo;
+    int minor, port_no;
     struct ifreq ifr;
     int error;
     int sock;
@@ -485,14 +486,20 @@ lookup_minor(const char *name, int *minor)
         goto error_close_sock;
     }
 
-    if (!isdigit(drvinfo.bus_info[0])) {
-        VLOG_WARN("%s ethtool info does not contain an openvswitch minor",
-                  name);
+    if (sscanf(drvinfo.bus_info, "%d.%d", &minor, &port_no) != 2) {
+        VLOG_WARN("%s ethtool bus_info has unexpected format", name);
         error = EPROTOTYPE;
         goto error_close_sock;
+    } else if (port_no != ODPP_LOCAL) {
+        /* This is an Open vSwitch device but not the local port.  We
+         * intentionally support only using the name of the local port as the
+         * name of a datapath; otherwise, it would be too difficult to
+         * enumerate all the names of a datapath. */
+        error = EOPNOTSUPP;
+        goto error_close_sock;
     }
 
-    *minor = atoi(drvinfo.bus_info);
+    *minorp = minor;
     close(sock);
     return 0;