tests: (mkfds) add a factor for opening tun device

Signed-off-by: Masatake YAMATO <yamato@redhat.com>

diff --git a/tests/helpers/test_mkfds.c b/tests/helpers/test_mkfds.c
index ff6e930874968fe9766a61899bb0d6cfd0eebdfe..ab75025949d7d4cc487baf90743f7435b1c040b7 100644 (file)
--- a/tests/helpers/test_mkfds.c
+++ b/tests/helpers/test_mkfds.c
@@ -25,6 +25,7 @@
 #include <getopt.h>
 #include <linux/if_ether.h>
 #include <linux/if_packet.h>
+#include <linux/if_tun.h>
 #include <linux/netlink.h>
 #include <linux/sockios.h>  /* SIOCGSKNS */
 #include <mqueue.h>
@@ -2466,6 +2467,62 @@ static void *make_signalfd(const struct factory *factory _U_, struct fdesc fdesc
        return NULL;
 }
 
+
+/* ref. linux/Documentation/networking/tuntap.rst */
+static void *make_cdev_tun(const struct factory *factory _U_, struct fdesc fdescs[],
+                          int argc _U_, char ** argv _U_)
+{
+       int tfd = open("/dev/net/tun", O_RDWR);
+       struct ifreq ifr;
+
+       if (tfd < 0)
+               err(EXIT_FAILURE, "failed in opening /dev/net/tun");
+
+       memset(&ifr, 0, sizeof(ifr));
+
+       ifr.ifr_flags = IFF_TUN;
+       strcpy(ifr.ifr_name, "mkfds%d");
+
+       if (ioctl(tfd, TUNSETIFF, (void *) &ifr) < 0) {
+               int e = errno;
+               close(tfd);
+               errno = e;
+               err(EXIT_FAILURE, "failed in setting \"lo\" to the tun device");
+       }
+
+       if (tfd != fdescs[0].fd) {
+               if (dup2(tfd, fdescs[0].fd) < 0) {
+                       int e = errno;
+                       close(tfd);
+                       errno = e;
+                       err(EXIT_FAILURE, "failed to dup %d -> %d", tfd, fdescs[0].fd);
+               }
+               close(tfd);
+       }
+
+       fdescs[0] = (struct fdesc){
+               .fd    = fdescs[0].fd,
+               .close = close_fdesc,
+               .data  = NULL
+       };
+
+       return xstrdup(ifr.ifr_name);
+}
+
+static void report_cdev_tun(const struct factory *factory _U_,
+                           int nth, void *data, FILE *fp)
+{
+       if (nth == 0) {
+               char *devname = data;
+               fprintf(fp, "%s", devname);
+       }
+}
+
+static void free_cdev_tun(const struct factory * factory _U_, void *data)
+{
+       free(data);
+}
+
 #define PARAM_END { .name = NULL, }
 static const struct factory factories[] = {
        {
@@ -3139,6 +3196,20 @@ static const struct factory factories[] = {
                        PARAM_END
                }
        },
+       {
+               .name = "cdev-tun",
+               .desc = "open /dev/net/tun",
+               .priv = true,
+               .N    = 1,
+               .EX_N = 0,
+               .EX_R = 1,
+               .make = make_cdev_tun,
+               .report = report_cdev_tun,
+               .free = free_cdev_tun,
+               .params = (struct parameter []) {
+                       PARAM_END
+               }
+       },
 };
 
 static int count_parameters(const struct factory *factory)