if: Ignore TAP interfaces by default

TAP interfaces are virtual ethernet and not really distinguishable
from real interfaces other than the interface name.

On BSD the interfaces are always called tapN.

diff --git a/src/if-bsd.c b/src/if-bsd.c
index 89013b1120f52055cad7f98a5b6d04b1222f2b0f..476a3fe27f8153cdb9c30f6185b393ca646a422c 100644 (file)
--- a/src/if-bsd.c
+++ b/src/if-bsd.c
@@ -101,6 +101,12 @@
 #define RT_ADVANCE(x, n) (x += RT_ROUNDUP((n)->sa_len))
 #endif
 
+/* Ignore these interface names which look like ethernet but are virtual. */
+static const char * const ifnames_ignore[] = {
+       "tap",
+       NULL
+};
+
 #ifdef INET6
 static void ifa_setscope(struct sockaddr_in6 *, unsigned int);
 static unsigned int ifa_getscope(const struct sockaddr_in6 *);
@@ -208,6 +214,18 @@ if_closesockets_os(struct dhcpcd_ctx *ctx)
                close(priv->pf_inet6_fd);
 }
 
+bool
+if_ignore(const char *drvname)
+{
+       const char * const *p;
+
+       for (p = ifnames_ignore; *p; p++) {
+               if (strcmp(*p, drvname) == 0)
+                       return true;
+       }
+       return false;
+}
+
 int
 if_carrier(struct interface *ifp)
 {

diff --git a/src/if-linux.c b/src/if-linux.c
index 57e6030e52e897ea4a6cb63aef6363612632ec8d..061b1fa89a33a9f0eaeafe4f89954bffc060ff3e 100644 (file)
--- a/src/if-linux.c
+++ b/src/if-linux.c
@@ -252,6 +252,14 @@ if_conf(struct interface *ifp)
        return 0;
 }
 
+/* XXX work out TAP interfaces? */
+bool
+if_ignore(__unused const char *drvname)
+{
+
+       return false;
+}
+
 /* XXX work out Virtal Interface Masters */
 int
 if_vimaster(__unused const struct dhcpcd_ctx *ctx, __unused const char *ifname)

diff --git a/src/if-sun.c b/src/if-sun.c
index 687a6ad093d7bb1625d999cdc5a671b8950370a4..4008698f86d72df2828b357ea13909c28aee8e10 100644 (file)
--- a/src/if-sun.c
+++ b/src/if-sun.c
@@ -249,14 +249,21 @@ if_mtu_os(const struct interface *ifp)
 }
 
 int
-if_getssid(struct interface *ifp)
+if_getssid(__unused struct interface *ifp)
 {
 
-       UNUSED(ifp);
        errno = ENOTSUP;
        return -1;
 }
 
+/* XXX work out TAP interfaces? */
+bool
+if_ignore(__unused const char *drvname)
+{
+
+       return false;
+}
+
 unsigned short
 if_vlanid(__unused const struct interface *ifp)
 {

diff --git a/src/if.c b/src/if.c
index c483f046ff2e62feb9c1dc890de3e3171d4bda4c..b9cf63edd011f6f21278517d8c28410e05a9d8e0 100644 (file)
--- a/src/if.c
+++ b/src/if.c
@@ -405,13 +405,6 @@ if_discover(struct dhcpcd_ctx *ctx, struct ifaddrs **ifaddrs,
                        continue;
 #endif
 
-               /* Don't allow loopback or pointopoint unless explicit */
-               if (ifa->ifa_flags & (IFF_LOOPBACK | IFF_POINTOPOINT)) {
-                       if ((argc == 0 || argc == -1) &&
-                           ctx->ifac == 0 && !if_hasconf(ctx, spec.devname))
-                               active = IF_INACTIVE;
-               }
-
                if (if_vimaster(ctx, spec.devname) == 1) {
                        logfunc_t *logfunc = argc != 0 ? logerrx : logdebugx;
                        logfunc("%s: is a Virtual Interface Master, skipping",
@@ -419,6 +412,17 @@ if_discover(struct dhcpcd_ctx *ctx, struct ifaddrs **ifaddrs,
                        continue;
                }
 
+#define        IF_NOCONF       ((argc == 0 || argc == -1) && ctx->ifac == 0 && \
+                        !if_hasconf(ctx, spec.devname))
+
+               /* Don't allow loopback or pointopoint unless explicit.
+                * Don't allow some reserved interface names unless explicit. */
+               if (IF_NOCONF) {
+                       if (ifa->ifa_flags & (IFF_LOOPBACK | IFF_POINTOPOINT) ||
+                           if_ignore(spec.drvname))
+                               active = IF_INACTIVE;
+               }
+
                ifp = calloc(1, sizeof(*ifp));
                if (ifp == NULL) {
                        logerr(__func__);
@@ -495,9 +499,7 @@ if_discover(struct dhcpcd_ctx *ctx, struct ifaddrs **ifaddrs,
 #endif
                        default:
                                /* Don't allow unless explicit */
-                               if ((argc == 0 || argc == -1) &&
-                                   ctx->ifac == 0 &&
-                                   !if_hasconf(ctx, ifp->name))
+                               if (IF_NOCONF)
                                        active = IF_INACTIVE;
                                if (active)
                                        logwarnx("%s: unsupported"

diff --git a/src/if.h b/src/if.h
index 4126fd33e4c49e705a21d57d5d52889752177d6f..0800c102a3298079b0a5cd521bb8e0ac287ebfaa 100644 (file)
--- a/src/if.h
+++ b/src/if.h
@@ -152,6 +152,7 @@ int if_nametospec(const char *, struct if_spec *);
 int if_conf(struct interface *);
 int if_init(struct interface *);
 int if_getssid(struct interface *);
+bool if_ignore(const char *);
 int if_vimaster(const struct dhcpcd_ctx *ctx, const char *);
 unsigned short if_vlanid(const struct interface *);
 int if_opensockets(struct dhcpcd_ctx *);