1 files changed, 254 insertions, 0 deletions
diff --git a/meta-facebook/meta-wedge/recipes-wedge/oob-nic/oob-nic/src/intf.c b/meta-facebook/meta-wedge/recipes-wedge/oob-nic/oob-nic/src/intf.c
new file mode 100644
index 0000000..5bf8480
--- /dev/null
+++ b/meta-facebook/meta-wedge/recipes-wedge/oob-nic/oob-nic/src/intf.c
@@ -0,0 +1,254 @@
+/*
+ * Copyright 2014-present Facebook. All Rights Reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include "intf.h"
+
+#include <errno.h>
+#include <fcntl.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <sys/ioctl.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <linux/rtnetlink.h>
+#include <linux/if.h>
+#include <linux/if_tun.h>
+#include <linux/fib_rules.h>
+
+#include "facebook/log.h"
+#include "libnetlink.h"
+#include "ll_map.h"
+
+struct oob_intf_t {
+  char oi_name[32];
+  int oi_fd;
+  int oi_ifidx;
+  uint8_t oi_mac[6];
+  struct rtnl_handle oi_rth;
+};
+
+#define TUN_DEVICE "/dev/net/tun"
+
+static int oob_intf_set_mac(oob_intf *intf, const uint8_t mac[6]) {
+  int rc;
+  struct {
+    struct nlmsghdr n;
+    struct ifinfomsg ifi;
+    char buf[256];
+  } req;
+
+  memset(&req, 0, sizeof(req));
+  req.n.nlmsg_len = NLMSG_LENGTH(sizeof(struct ifinfomsg));
+  req.n.nlmsg_type = RTM_NEWLINK;
+  req.n.nlmsg_flags = NLM_F_REQUEST;
+  req.ifi.ifi_family = AF_UNSPEC;
+  req.ifi.ifi_index = intf->oi_ifidx;
+  memcpy(intf->oi_mac, mac, sizeof(intf->oi_mac));
+  addattr_l(&req.n, sizeof(req), IFLA_ADDRESS,
+            intf->oi_mac, sizeof(intf->oi_mac));
+  rc = rtnl_talk(&intf->oi_rth, &req.n, 0, 0, NULL);
+  if (rc < 0) {
+    rc = errno;
+    LOG_ERR(rc, "Failed to set mac to interface %s @ index %d",
+            intf->oi_name, intf->oi_ifidx);
+    return -rc;
+  }
+
+  LOG_INFO("Set interface %s @ index %d mac to %x:%x:%x:%x:%x:%x",
+           intf->oi_name, intf->oi_ifidx,
+           intf->oi_mac[0], intf->oi_mac[1], intf->oi_mac[2],
+           intf->oi_mac[3], intf->oi_mac[4], intf->oi_mac[5]);
+
+  return 0;
+}
+
+static int oob_intf_bring_up(oob_intf *intf) {
+  int rc;
+  struct {
+    struct nlmsghdr n;
+    struct ifinfomsg ifi;
+    char buf[256];
+  } req;
+
+  memset(&req, 0, sizeof(req));
+  req.n.nlmsg_len = NLMSG_LENGTH(sizeof(struct ifinfomsg));
+  req.n.nlmsg_type = RTM_NEWLINK;
+  req.n.nlmsg_flags = NLM_F_REQUEST;
+  req.ifi.ifi_family = AF_UNSPEC;
+  req.ifi.ifi_change |= IFF_UP;
+  req.ifi.ifi_flags |= IFF_UP;
+  req.ifi.ifi_index = intf->oi_ifidx;
+  rc = rtnl_talk(&intf->oi_rth, &req.n, 0, 0, NULL);
+  if (rc < 0) {
+    rc = errno;
+    LOG_ERR(rc, "Failed to bring up interface %s @ index %d",
+            intf->oi_name, intf->oi_ifidx);
+    return -rc;
+  }
+
+  LOG_INFO("Brought up interface %s @ index %d", intf->oi_name, intf->oi_ifidx);
+
+  return 0;
+}
+
+oob_intf* oob_intf_create(const char *name, const uint8_t mac[6]) {
+
+  int rc;
+  int flags;
+  struct ifreq ifr;
+  oob_intf *intf = NULL;
+
+#define _CHECK_RC(fmt, ...) do {                \
+  if (rc < 0) {                                 \
+    rc = errno;                                 \
+    LOG_ERR(rc, fmt, ##__VA_ARGS__);            \
+    goto err_out;                               \
+  }                                             \
+} while(0)
+
+  intf = malloc(sizeof(*intf));
+  if (!intf) {
+    rc = ENOMEM;
+    LOG_ERR(rc, "Failed to allocate memory for interface");
+    goto err_out;
+  }
+  memset(intf, 0, sizeof(*intf));
+  strncpy(intf->oi_name, name, sizeof(intf->oi_name));
+  intf->oi_name[sizeof(intf->oi_name) - 1] = '\0';
+  intf->oi_fd = -1;
+
+  rc = rtnl_open(&intf->oi_rth, 0);
+  _CHECK_RC("Failed to open rth_handler");
+
+  rc = open(TUN_DEVICE, O_RDWR);
+  _CHECK_RC("Failed to open %s", TUN_DEVICE);
+  intf->oi_fd = rc;
+
+  memset(&ifr, 0, sizeof(ifr));
+  /*
+   * IFF_TAP: TAP interface
+   * IFF_NO_PI: Do not provide pracket information
+   */
+  ifr.ifr_flags = IFF_TAP|IFF_NO_PI;
+  strncpy(ifr.ifr_name, name, sizeof(ifr.ifr_name));
+  ifr.ifr_name[sizeof(ifr.ifr_name) - 1] = '\0';
+
+  rc = ioctl(intf->oi_fd, TUNSETIFF, (void *) &ifr);
+  _CHECK_RC("Failed to create tap interface %s", ifr.ifr_name);
+
+  /* make fd non-blocking */
+  rc = fcntl(intf->oi_fd, F_GETFL);
+  _CHECK_RC("Failed to get flags from fd ", intf->oi_fd);
+  flags = rc | O_NONBLOCK;
+  rc = fcntl(intf->oi_fd, F_SETFL, rc);
+  _CHECK_RC("Failed to set non-blocking flags ", flags,
+            " to fd ", intf->oi_fd);
+
+  /* set CLOEXEC */
+  rc = fcntl(intf->oi_fd, F_GETFD);
+  _CHECK_RC("Failed to get flags from fd ", intf->oi_fd);
+  flags = rc | FD_CLOEXEC;
+  rc = fcntl(intf->oi_fd, F_SETFD, flags);
+  _CHECK_RC("Failed to set close-on-exec flags ", flags,
+            " to fd ", intf->oi_fd);
+
+  // TODO: if needed, we can adjust send buffer size, TUNSETSNDBUF
+  intf->oi_ifidx = ll_name_to_index(intf->oi_name);
+
+  /* now set the mac address */
+  oob_intf_set_mac(intf, mac);
+
+#if 0
+  /* make it persistent */
+  rc = ioctl(intf->oi_fd, TUNSETPERSIST, 0);
+  _CHECK_RC("Failed to make the tap interface %s persistent", intf->oi_name);
+#endif
+
+  LOG_INFO("Create/attach to tap interface %s @ fd %d, index %d",
+           intf->oi_name, intf->oi_fd, intf->oi_ifidx);
+
+  //oob_intf_bring_up(intf);
+
+  return intf;
+
+ err_out:
+  if (intf) {
+    rtnl_close(&intf->oi_rth);
+    if (intf->oi_fd != -1) {
+      close(intf->oi_fd);
+    }
+    free(intf);
+  }
+
+  return NULL;
+}
+
+int oob_intf_get_fd(const oob_intf *intf) {
+  return intf->oi_fd;
+}
+
+int oob_intf_receive(const oob_intf *intf, char *buf, int len) {
+  int rc;
+  do {
+    rc = read(intf->oi_fd, buf, len);
+  } while (rc == -1 && errno == EINTR);
+  if (rc < 0) {
+    rc = errno;
+    if (rc != EAGAIN) {
+      LOG_ERR(rc, "Failed to read on interface fd %d", intf->oi_fd);
+      return -rc;
+    } else {
+      /* nothing is available */
+      return 0;
+    }
+  } else if (rc == 0) {
+    // Nothing to read. It shall not happen as the fd is non-blocking.
+    // Just add this case to be safe.
+    return 0;
+  } else if (rc > len) {
+    // The pkt is larger than the buffer. We don't have complete packet.
+    // It shall not happen unless the MTU is mis-match. Drop the packet.
+    LOG_ERR(ENOSPC, "Received a too large packet (%d bytes > %d) from the "
+            "tap interface. Drop it...", rc, len);
+    return -ENOSPC;
+  } else {
+    LOG_VER("Recv a packet of %d bytes from %s", rc, intf->oi_name);
+    return rc;
+  }
+}
+
+int oob_intf_send(const oob_intf *intf, const char *buf, int len) {
+  int rc;
+  do {
+    rc = write(intf->oi_fd, buf, len);
+  } while (rc == -1 && errno == EINTR);
+  if (rc < 0) {
+    rc = errno;
+    LOG_ERR(rc, "Failed to send on interface fd %d", intf->oi_fd);
+    return -rc;
+  } else if (rc < len) {
+    LOG_ERR(EIO, "Failed to send the full packet (%d bytes > %d) for fd %d",
+            len, rc, intf->oi_fd);
+    return -EIO;
+  } else {
+    LOG_VER("Sent a packet of %d bytes to %s", rc, intf->oi_name);
+    return rc;
+  }
+}