path: root/lib/vrf.c

/*
 * VRF functions.
 * Copyright (C) 2014 6WIND S.A.
 *
 * This file is part of GNU Zebra.
 *
 * GNU Zebra 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, or (at your
 * option) any later version.
 *
 * GNU Zebra 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 GNU Zebra; see the file COPYING.  If not, write to the
 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
 * Boston, MA 02111-1307, USA.
 */

#include <zebra.h>

#include "if.h"
#include "vrf.h"
#include "prefix.h"
#include "table.h"
#include "log.h"
#include "memory.h"
#include "command.h"

DEFINE_MTYPE_STATIC(LIB, VRF,        "VRF")
DEFINE_MTYPE_STATIC(LIB, VRF_BITMAP, "VRF bit-map")

DEFINE_QOBJ_TYPE(vrf)

static __inline int vrf_id_compare (struct vrf *, struct vrf *);
static __inline int vrf_name_compare (struct vrf *, struct vrf *);

RB_GENERATE (vrf_id_head, vrf, id_entry, vrf_id_compare)
RB_GENERATE (vrf_name_head, vrf, name_entry, vrf_name_compare)

struct vrf_id_head vrfs_by_id = RB_INITIALIZER (&vrfs_by_id);
struct vrf_name_head vrfs_by_name = RB_INITIALIZER (&vrfs_by_name);

/*
 * Turn on/off debug code
 * for vrf.
 */
int debug_vrf = 0;

/* Holding VRF hooks  */
struct vrf_master
{
  int (*vrf_new_hook) (struct vrf *);
  int (*vrf_delete_hook) (struct vrf *);
  int (*vrf_enable_hook) (struct vrf *);
  int (*vrf_disable_hook) (struct vrf *);
} vrf_master = {0,};

static int vrf_is_enabled (struct vrf *vrf);
static void vrf_disable (struct vrf *vrf);

/* VRF list existance check by name. */
struct vrf *
vrf_lookup_by_name (const char *name)
{
  struct vrf vrf;
  strlcpy (vrf.name, name, sizeof (vrf.name));
  return (RB_FIND (vrf_name_head, &vrfs_by_name, &vrf));
}

static __inline int
vrf_id_compare (struct vrf *a, struct vrf *b)
{
  return (a->vrf_id - b->vrf_id);
}

static int
vrf_name_compare (struct vrf *a, struct vrf *b)
{
  return strcmp (a->name, b->name);
}

/* Get a VRF. If not found, create one.
 * Arg:
 *   name   - The name of the vrf.  May be NULL if unknown.
 *   vrf_id - The vrf_id of the vrf.  May be VRF_UNKNOWN if unknown
 * Description: Please note that this routine can be called with just the name
 * and 0 vrf-id
 */
struct vrf *
vrf_get (vrf_id_t vrf_id, const char *name)
{
  struct vrf *vrf = NULL;
  int new = 0;

  if (debug_vrf)
    zlog_debug ("VRF_GET: %s(%d)", name, vrf_id);

  /* Nothing to see, move along here */
  if (!name && vrf_id == VRF_UNKNOWN)
    return NULL;

  /* Try to find VRF both by ID and name */
  if (vrf_id != VRF_UNKNOWN)
    vrf = vrf_lookup_by_id (vrf_id);
  if (! vrf && name)
    vrf = vrf_lookup_by_name (name);

  if (vrf == NULL)
    {
      vrf = XCALLOC (MTYPE_VRF, sizeof (struct vrf));
      vrf->vrf_id = VRF_UNKNOWN;
      if_init (&vrf->iflist);
      QOBJ_REG (vrf, vrf);
      new = 1;

      if (debug_vrf)
	zlog_debug ("VRF(%u) %s is created.",
		    vrf_id, (name) ? name : "(NULL)");
    }

  /* Set identifier */
  if (vrf_id != VRF_UNKNOWN && vrf->vrf_id == VRF_UNKNOWN)
    {
      vrf->vrf_id = vrf_id;
      RB_INSERT (vrf_id_head, &vrfs_by_id, vrf);
    }

  /* Set name */
  if (name && vrf->name[0] != '\0' && strcmp (name, vrf->name))
    {
      RB_REMOVE (vrf_name_head, &vrfs_by_name, vrf);
      strlcpy (vrf->name, name, sizeof (vrf->name));
      RB_INSERT (vrf_name_head, &vrfs_by_name, vrf);
    }
  else if (name && vrf->name[0] == '\0')
    {
      strlcpy (vrf->name, name, sizeof (vrf->name));
      RB_INSERT (vrf_name_head, &vrfs_by_name, vrf);
    }

  if (new && vrf_master.vrf_new_hook)
    (*vrf_master.vrf_new_hook) (vrf);

  return vrf;
}

/* Delete a VRF. This is called in vrf_terminate(). */
void
vrf_delete (struct vrf *vrf)
{
  if (debug_vrf)
    zlog_debug ("VRF %u is to be deleted.", vrf->vrf_id);

  if (vrf_is_enabled (vrf))
    vrf_disable (vrf);

  if (vrf_master.vrf_delete_hook)
    (*vrf_master.vrf_delete_hook) (vrf);

  QOBJ_UNREG (vrf);
  if_terminate (&vrf->iflist);

  if (vrf->vrf_id != VRF_UNKNOWN)
    RB_REMOVE (vrf_id_head, &vrfs_by_id, vrf);
  if (vrf->name[0] != '\0')
    RB_REMOVE (vrf_name_head, &vrfs_by_name, vrf);

  XFREE (MTYPE_VRF, vrf);
}

/* Look up a VRF by identifier. */
struct vrf *
vrf_lookup_by_id (vrf_id_t vrf_id)
{
  struct vrf vrf;
  vrf.vrf_id = vrf_id;
  return (RB_FIND (vrf_id_head, &vrfs_by_id, &vrf));
}

/*
 * Check whether the VRF is enabled.
 */
static int
vrf_is_enabled (struct vrf *vrf)
{
  return vrf && CHECK_FLAG (vrf->status, VRF_ACTIVE);
}

/*
 * Enable a VRF - that is, let the VRF be ready to use.
 * The VRF_ENABLE_HOOK callback will be called to inform
 * that they can allocate resources in this VRF.
 *
 * RETURN: 1 - enabled successfully; otherwise, 0.
 */
int
vrf_enable (struct vrf *vrf)
{
  if (vrf_is_enabled (vrf))
    return 1;

  if (debug_vrf)
    zlog_debug ("VRF %u is enabled.", vrf->vrf_id);

  SET_FLAG (vrf->status, VRF_ACTIVE);

  if (vrf_master.vrf_enable_hook)
    (*vrf_master.vrf_enable_hook) (vrf);

  return 1;
}

/*
 * Disable a VRF - that is, let the VRF be unusable.
 * The VRF_DELETE_HOOK callback will be called to inform
 * that they must release the resources in the VRF.
 */
static void
vrf_disable (struct vrf *vrf)
{
  if (! vrf_is_enabled (vrf))
    return;

  UNSET_FLAG (vrf->status, VRF_ACTIVE);

  if (debug_vrf)
    zlog_debug ("VRF %u is to be disabled.", vrf->vrf_id);

  /* Till now, nothing to be done for the default VRF. */
  //Pending: see why this statement.

  if (vrf_master.vrf_disable_hook)
    (*vrf_master.vrf_disable_hook) (vrf);
}


/* Add a VRF hook. Please add hooks before calling vrf_init(). */
void
vrf_add_hook (int type, int (*func)(struct vrf *))
{
  if (debug_vrf)
    zlog_debug ("%s: Add Hook %d to function %p",  __PRETTY_FUNCTION__,
		type, func);

  switch (type) {
  case VRF_NEW_HOOK:
    vrf_master.vrf_new_hook = func;
    break;
  case VRF_DELETE_HOOK:
    vrf_master.vrf_delete_hook = func;
    break;
  case VRF_ENABLE_HOOK:
    vrf_master.vrf_enable_hook = func;
    break;
  case VRF_DISABLE_HOOK:
    vrf_master.vrf_disable_hook = func;
    break;
  default:
    break;
  }
}

vrf_id_t
vrf_name_to_id (const char *name)
{
  struct vrf *vrf;
  vrf_id_t vrf_id = VRF_DEFAULT; //Pending: need a way to return invalid id/ routine not used.

  vrf = vrf_lookup_by_name (name);
  if (vrf)
    vrf_id = vrf->vrf_id;

  return vrf_id;
}

/* Get the data pointer of the specified VRF. If not found, create one. */
void *
vrf_info_get (vrf_id_t vrf_id)
{
  struct vrf *vrf = vrf_get (vrf_id, NULL);
  return vrf->info;
}

/* Look up the data pointer of the specified VRF. */
void *
vrf_info_lookup (vrf_id_t vrf_id)
{
  struct vrf *vrf = vrf_lookup_by_id (vrf_id);
  return vrf ? vrf->info : NULL;
}

/* Look up the interface list in a VRF. */
struct list *
vrf_iflist (vrf_id_t vrf_id)
{
   struct vrf * vrf = vrf_lookup_by_id (vrf_id);
   return vrf ? vrf->iflist : NULL;
}

/* Get the interface list of the specified VRF. Create one if not find. */
struct list *
vrf_iflist_get (vrf_id_t vrf_id)
{
   struct vrf * vrf = vrf_get (vrf_id, NULL);
   return vrf->iflist;
}

/* Create the interface list for the specified VRF, if needed. */
void
vrf_iflist_create (vrf_id_t vrf_id)
{
   struct vrf * vrf = vrf_lookup_by_id (vrf_id);
   if (vrf && !vrf->iflist)
     if_init (&vrf->iflist);
}

/* Free the interface list of the specified VRF. */
void
vrf_iflist_terminate (vrf_id_t vrf_id)
{
   struct vrf * vrf = vrf_lookup_by_id (vrf_id);
   if (vrf && vrf->iflist)
     if_terminate (&vrf->iflist);
}

/*
 * VRF bit-map
 */

#define VRF_BITMAP_NUM_OF_GROUPS            8
#define VRF_BITMAP_NUM_OF_BITS_IN_GROUP \
    (UINT16_MAX / VRF_BITMAP_NUM_OF_GROUPS)
#define VRF_BITMAP_NUM_OF_BYTES_IN_GROUP \
    (VRF_BITMAP_NUM_OF_BITS_IN_GROUP / CHAR_BIT + 1) /* +1 for ensure */

#define VRF_BITMAP_GROUP(_id) \
    ((_id) / VRF_BITMAP_NUM_OF_BITS_IN_GROUP)
#define VRF_BITMAP_BIT_OFFSET(_id) \
    ((_id) % VRF_BITMAP_NUM_OF_BITS_IN_GROUP)

#define VRF_BITMAP_INDEX_IN_GROUP(_bit_offset) \
    ((_bit_offset) / CHAR_BIT)
#define VRF_BITMAP_FLAG(_bit_offset) \
    (((u_char)1) << ((_bit_offset) % CHAR_BIT))

struct vrf_bitmap
{
  u_char *groups[VRF_BITMAP_NUM_OF_GROUPS];
};

vrf_bitmap_t
vrf_bitmap_init (void)
{
  return (vrf_bitmap_t) XCALLOC (MTYPE_VRF_BITMAP, sizeof (struct vrf_bitmap));
}

void
vrf_bitmap_free (vrf_bitmap_t bmap)
{
  struct vrf_bitmap *bm = (struct vrf_bitmap *) bmap;
  int i;

  if (bmap == VRF_BITMAP_NULL)
    return;

  for (i = 0; i < VRF_BITMAP_NUM_OF_GROUPS; i++)
    if (bm->groups[i])
      XFREE (MTYPE_VRF_BITMAP, bm->groups[i]);

  XFREE (MTYPE_VRF_BITMAP, bm);
}

void
vrf_bitmap_set (vrf_bitmap_t bmap, vrf_id_t vrf_id)
{
  struct vrf_bitmap *bm = (struct vrf_bitmap *) bmap;
  u_char group = VRF_BITMAP_GROUP (vrf_id);
  u_char offset = VRF_BITMAP_BIT_OFFSET (vrf_id);

  if (bmap == VRF_BITMAP_NULL)
    return;

  if (bm->groups[group] == NULL)
    bm->groups[group] = XCALLOC (MTYPE_VRF_BITMAP,
                                 VRF_BITMAP_NUM_OF_BYTES_IN_GROUP);

  SET_FLAG (bm->groups[group][VRF_BITMAP_INDEX_IN_GROUP (offset)],
            VRF_BITMAP_FLAG (offset));
}

void
vrf_bitmap_unset (vrf_bitmap_t bmap, vrf_id_t vrf_id)
{
  struct vrf_bitmap *bm = (struct vrf_bitmap *) bmap;
  u_char group = VRF_BITMAP_GROUP (vrf_id);
  u_char offset = VRF_BITMAP_BIT_OFFSET (vrf_id);

  if (bmap == VRF_BITMAP_NULL || bm->groups[group] == NULL)
    return;

  UNSET_FLAG (bm->groups[group][VRF_BITMAP_INDEX_IN_GROUP (offset)],
              VRF_BITMAP_FLAG (offset));
}

int
vrf_bitmap_check (vrf_bitmap_t bmap, vrf_id_t vrf_id)
{
  struct vrf_bitmap *bm = (struct vrf_bitmap *) bmap;
  u_char group = VRF_BITMAP_GROUP (vrf_id);
  u_char offset = VRF_BITMAP_BIT_OFFSET (vrf_id);

  if (bmap == VRF_BITMAP_NULL || bm->groups[group] == NULL)
    return 0;

  return CHECK_FLAG (bm->groups[group][VRF_BITMAP_INDEX_IN_GROUP (offset)],
                     VRF_BITMAP_FLAG (offset)) ? 1 : 0;
}

/* Initialize VRF module. */
void
vrf_init (void)
{
  struct vrf *default_vrf;

  if (debug_vrf)
    zlog_debug ("%s: Initializing VRF subsystem", __PRETTY_FUNCTION__);

  /* The default VRF always exists. */
  default_vrf = vrf_get (VRF_DEFAULT, VRF_DEFAULT_NAME);
  if (!default_vrf)
    {
      zlog_err ("vrf_init: failed to create the default VRF!");
      exit (1);
    }

  /* Enable the default VRF. */
  if (!vrf_enable (default_vrf))
    {
      zlog_err ("vrf_init: failed to enable the default VRF!");
      exit (1);
    }
}

/* Terminate VRF module. */
void
vrf_terminate (void)
{
  struct vrf *vrf;

  if (debug_vrf)
    zlog_debug ("%s: Shutting down vrf subsystem", __PRETTY_FUNCTION__);

  while ((vrf = RB_ROOT (&vrfs_by_id)) != NULL)
    vrf_delete (vrf);
  while ((vrf = RB_ROOT (&vrfs_by_name)) != NULL)
    vrf_delete (vrf);
}

/* Create a socket for the VRF. */
int
vrf_socket (int domain, int type, int protocol, vrf_id_t vrf_id)
{
  int ret = -1;

  ret = socket (domain, type, protocol);

  return ret;
}

/* vrf CLI commands */
DEFUN (vrf,
       vrf_cmd,
       "vrf NAME",
       "Select a VRF to configure\n"
       "VRF's name\n")
{
  int idx_name = 1;
  const char *vrfname = argv[idx_name]->arg;

  struct vrf *vrfp;
  size_t sl;

  if ((sl = strlen(vrfname)) > VRF_NAMSIZ)
    {
      vty_out (vty, "%% VRF name %s is invalid: length exceeds "
                    "%d characters%s",
               vrfname, VRF_NAMSIZ, VTY_NEWLINE);
      return CMD_WARNING;
    }

  vrfp = vrf_get (VRF_UNKNOWN, vrfname);

  VTY_PUSH_CONTEXT_COMPAT (VRF_NODE, vrfp);

  return CMD_SUCCESS;
}

DEFUN_NOSH (no_vrf,
           no_vrf_cmd,
           "no vrf NAME",
           NO_STR
           "Delete a pseudo VRF's configuration\n"
           "VRF's name\n")
{
  const char *vrfname = argv[2]->arg;

  struct vrf *vrfp;

  vrfp = vrf_lookup_by_name (vrfname);

  if (vrfp == NULL)
    {
      vty_out (vty, "%% VRF %s does not exist%s", vrfname, VTY_NEWLINE);
      return CMD_WARNING;
    }

  if (CHECK_FLAG (vrfp->status, VRF_ACTIVE))
    {
      vty_out (vty, "%% Only inactive VRFs can be deleted%s",
              VTY_NEWLINE);
      return CMD_WARNING;
    }

  vrf_delete(vrfp);

  return CMD_SUCCESS;
}


/*
 * Debug CLI for vrf's
 */
DEFUN (vrf_debug,
      vrf_debug_cmd,
      "debug vrf",
      DEBUG_STR
      "VRF Debugging\n")
{
  debug_vrf = 1;

  return CMD_SUCCESS;
}

DEFUN (no_vrf_debug,
      no_vrf_debug_cmd,
      "no debug vrf",
      NO_STR
      DEBUG_STR
      "VRF Debugging\n")
{
  debug_vrf = 0;

  return CMD_SUCCESS;
}

static int
vrf_write_host (struct vty *vty)
{
  if (debug_vrf)
    vty_out (vty, "debug vrf%s", VTY_NEWLINE);

  return 1;
}

static struct cmd_node vrf_debug_node =
{
  VRF_DEBUG_NODE,
  "",
  1
};

void
vrf_install_commands (void)
{
  install_node (&vrf_debug_node, vrf_write_host);

  install_element (CONFIG_NODE, &vrf_debug_cmd);
  install_element (ENABLE_NODE, &vrf_debug_cmd);
  install_element (CONFIG_NODE, &no_vrf_debug_cmd);
  install_element (ENABLE_NODE, &no_vrf_debug_cmd);

  install_element (CONFIG_NODE, &vrf_cmd);
  install_element (CONFIG_NODE, &no_vrf_cmd);
}