Porting PicoTCP WIP

kernel/picotcp/modules/pico_dev_tun.c

@@ -0,0 +1,110 @@
+/*********************************************************************
+   PicoTCP. Copyright (c) 2012-2017 Altran Intelligent Systems. Some rights reserved.
+   See COPYING, LICENSE.GPLv2 and LICENSE.GPLv3 for usage.
+
+   Authors: Daniele Lacamera
+ *********************************************************************/
+
+
+#include <fcntl.h>
+#include <sys/ioctl.h>
+#include <net/if.h>
+#include <linux/if_tun.h>
+#include "pico_device.h"
+#include "pico_dev_tun.h"
+#include "pico_stack.h"
+
+#include <sys/poll.h>
+
+struct pico_device_tun {
+    struct pico_device dev;
+    int fd;
+};
+
+#define TUN_MTU 2048
+
+static int pico_tun_send(struct pico_device *dev, void *buf, int len)
+{
+    struct pico_device_tun *tun = (struct pico_device_tun *) dev;
+    return (int)write(tun->fd, buf, (uint32_t)len);
+}
+
+static int pico_tun_poll(struct pico_device *dev, int loop_score)
+{
+    struct pico_device_tun *tun = (struct pico_device_tun *) dev;
+    struct pollfd pfd;
+    unsigned char buf[TUN_MTU];
+    int len;
+    pfd.fd = tun->fd;
+    pfd.events = POLLIN;
+    do  {
+        if (poll(&pfd, 1, 0) <= 0)
+            return loop_score;
+
+        len = (int)read(tun->fd, buf, TUN_MTU);
+        if (len > 0) {
+            loop_score--;
+            pico_stack_recv(dev, buf, (uint32_t)len);
+        }
+    } while(loop_score > 0);
+    return 0;
+}
+
+/* Public interface: create/destroy. */
+
+void pico_tun_destroy(struct pico_device *dev)
+{
+    struct pico_device_tun *tun = (struct pico_device_tun *) dev;
+    if(tun->fd > 0)
+        close(tun->fd);
+}
+
+
+static int tun_open(char *name)
+{
+    struct ifreq ifr;
+    int tun_fd;
+    if((tun_fd = open("/dev/net/tun", O_RDWR)) < 0) {
+        return(-1);
+    }
+
+    memset(&ifr, 0, sizeof(ifr));
+    ifr.ifr_flags = IFF_TUN | IFF_NO_PI;
+    strncpy(ifr.ifr_name, name, IFNAMSIZ);
+    if(ioctl(tun_fd, TUNSETIFF, &ifr) < 0) {
+        return(-1);
+    }
+
+    return tun_fd;
+}
+
+
+
+struct pico_device *pico_tun_create(char *name)
+{
+    struct pico_device_tun *tun = PICO_ZALLOC(sizeof(struct pico_device_tun));
+
+    if (!tun)
+        return NULL;
+
+    if( 0 != pico_device_init((struct pico_device *)tun, name, NULL)) {
+        dbg("Tun init failed.\n");
+        pico_tun_destroy((struct pico_device *)tun);
+        return NULL;
+    }
+
+    tun->dev.overhead = 0;
+    tun->fd = tun_open(name);
+    if (tun->fd < 0) {
+        dbg("Tun creation failed.\n");
+        pico_tun_destroy((struct pico_device *)tun);
+        return NULL;
+    }
+
+    tun->dev.send = pico_tun_send;
+    tun->dev.poll = pico_tun_poll;
+    tun->dev.destroy = pico_tun_destroy;
+    dbg("Device %s created.\n", tun->dev.name);
+    return (struct pico_device *)tun;
+}
+