#include "table.h"
#include "log.h"
#include "memory.h"
+#include "command.h"
-#define VRF_DEFAULT_NAME "Default-IP-Routing-Table"
+DEFINE_MTYPE_STATIC(LIB, VRF, "VRF")
+DEFINE_MTYPE_STATIC(LIB, VRF_BITMAP, "VRF bit-map")
-struct vrf
-{
- /* Identifier, same as the vector index */
- vrf_id_t vrf_id;
- /* Name */
- char *name;
+DEFINE_QOBJ_TYPE(vrf)
- /* Master list of interfaces belonging to this VRF */
- struct list *iflist;
+static __inline int vrf_id_compare (struct vrf *, struct vrf *);
+static __inline int vrf_name_compare (struct vrf *, struct vrf *);
- /* User data */
- void *info;
-};
+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) (vrf_id_t, void **);
- int (*vrf_delete_hook) (vrf_id_t, void **);
- int (*vrf_enable_hook) (vrf_id_t, void **);
- int (*vrf_disable_hook) (vrf_id_t, void **);
+ 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,};
-/* VRF table */
-struct route_table *vrf_table = NULL;
-
static int vrf_is_enabled (struct vrf *vrf);
-static int vrf_enable (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));
+}
-/* Build the table key */
-static void
-vrf_build_key (vrf_id_t vrf_id, struct prefix *p)
+static __inline int
+vrf_id_compare (struct vrf *a, struct vrf *b)
{
- p->family = AF_INET;
- p->prefixlen = IPV4_MAX_BITLEN;
- p->u.prefix4.s_addr = vrf_id;
+ return (a->vrf_id - b->vrf_id);
}
-/* Get a VRF. If not found, create one. */
-static struct vrf *
-vrf_get (vrf_id_t vrf_id)
+static int
+vrf_name_compare (struct vrf *a, struct vrf *b)
{
- struct prefix p;
- struct route_node *rn;
- struct vrf *vrf;
+ 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;
- vrf_build_key (vrf_id, &p);
- rn = route_node_get (vrf_table, &p);
- if (rn->info)
+ /* 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 = (struct vrf *)rn->info;
- route_unlock_node (rn); /* get */
- return vrf;
+ 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)");
}
- vrf = XCALLOC (MTYPE_VRF, sizeof (struct vrf));
- vrf->vrf_id = vrf_id;
- rn->info = vrf;
-
- /* Initialize interfaces. */
- if_init (vrf_id, &vrf->iflist);
+ /* 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);
+ }
- zlog_info ("VRF %u is created.", vrf_id);
+ /* 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 (vrf_master.vrf_new_hook)
- (*vrf_master.vrf_new_hook) (vrf_id, &vrf->info);
+ if (new && vrf_master.vrf_new_hook)
+ (*vrf_master.vrf_new_hook) (vrf);
return vrf;
}
/* Delete a VRF. This is called in vrf_terminate(). */
-static void
+void
vrf_delete (struct vrf *vrf)
{
- zlog_info ("VRF %u is to be deleted.", vrf->vrf_id);
+ 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->vrf_id, &vrf->info);
+ (*vrf_master.vrf_delete_hook) (vrf);
- if_terminate (vrf->vrf_id, &vrf->iflist);
+ QOBJ_UNREG (vrf);
+ if_terminate (&vrf->iflist);
- if (vrf->name)
- XFREE (MTYPE_VRF_NAME, vrf->name);
+ 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. */
-static struct vrf *
-vrf_lookup (vrf_id_t vrf_id)
+struct vrf *
+vrf_lookup_by_id (vrf_id_t vrf_id)
{
- struct prefix p;
- struct route_node *rn;
- struct vrf *vrf = NULL;
-
- vrf_build_key (vrf_id, &p);
- rn = route_node_lookup (vrf_table, &p);
- if (rn)
- {
- vrf = (struct vrf *)rn->info;
- route_unlock_node (rn); /* lookup */
- }
- return vrf;
+ struct vrf vrf;
+ vrf.vrf_id = vrf_id;
+ return (RB_FIND (vrf_id_head, &vrfs_by_id, &vrf));
}
/*
- * Check whether the VRF is enabled - that is, whether the VRF
- * is ready to allocate resources. Currently there's only one
- * type of resource: socket.
+ * Check whether the VRF is enabled.
*/
static int
vrf_is_enabled (struct vrf *vrf)
{
- return vrf && vrf->vrf_id == VRF_DEFAULT;
+ return vrf && CHECK_FLAG (vrf->status, VRF_ACTIVE);
}
/*
*
* RETURN: 1 - enabled successfully; otherwise, 0.
*/
-static int
+int
vrf_enable (struct vrf *vrf)
{
- /* Till now, only the default VRF can be enabled. */
- if (vrf->vrf_id == VRF_DEFAULT)
- {
- zlog_info ("VRF %u is enabled.", vrf->vrf_id);
+ if (vrf_is_enabled (vrf))
+ return 1;
- if (vrf_master.vrf_enable_hook)
- (*vrf_master.vrf_enable_hook) (vrf->vrf_id, &vrf->info);
+ if (debug_vrf)
+ zlog_debug ("VRF %u is enabled.", vrf->vrf_id);
- return 1;
- }
+ SET_FLAG (vrf->status, VRF_ACTIVE);
+
+ if (vrf_master.vrf_enable_hook)
+ (*vrf_master.vrf_enable_hook) (vrf);
- return 0;
+ return 1;
}
/*
static void
vrf_disable (struct vrf *vrf)
{
- if (vrf_is_enabled (vrf))
- {
- zlog_info ("VRF %u is to be disabled.", vrf->vrf_id);
+ if (! vrf_is_enabled (vrf))
+ return;
- /* Till now, nothing to be done for the default VRF. */
+ UNSET_FLAG (vrf->status, VRF_ACTIVE);
- if (vrf_master.vrf_disable_hook)
- (*vrf_master.vrf_disable_hook) (vrf->vrf_id, &vrf->info);
- }
+ 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)(vrf_id_t, 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;
}
}
-/* Return the iterator of the first VRF. */
-vrf_iter_t
-vrf_first (void)
-{
- struct route_node *rn;
-
- for (rn = route_top (vrf_table); rn; rn = route_next (rn))
- if (rn->info)
- {
- route_unlock_node (rn); /* top/next */
- return (vrf_iter_t)rn;
- }
- return VRF_ITER_INVALID;
-}
-
-/* Return the next VRF iterator to the given iterator. */
-vrf_iter_t
-vrf_next (vrf_iter_t iter)
-{
- struct route_node *rn = NULL;
-
- /* Lock it first because route_next() will unlock it. */
- if (iter != VRF_ITER_INVALID)
- rn = route_next (route_lock_node ((struct route_node *)iter));
-
- for (; rn; rn = route_next (rn))
- if (rn->info)
- {
- route_unlock_node (rn); /* next */
- return (vrf_iter_t)rn;
- }
- return VRF_ITER_INVALID;
-}
-
-/* Return the VRF iterator of the given VRF ID. If it does not exist,
- * the iterator of the next existing VRF is returned. */
-vrf_iter_t
-vrf_iterator (vrf_id_t vrf_id)
-{
- struct prefix p;
- struct route_node *rn;
-
- vrf_build_key (vrf_id, &p);
- rn = route_node_get (vrf_table, &p);
- if (rn->info)
- {
- /* OK, the VRF exists. */
- route_unlock_node (rn); /* get */
- return (vrf_iter_t)rn;
- }
-
- /* Find the next VRF. */
- for (rn = route_next (rn); rn; rn = route_next (rn))
- if (rn->info)
- {
- route_unlock_node (rn); /* next */
- return (vrf_iter_t)rn;
- }
-
- return VRF_ITER_INVALID;
-}
-
-/* Obtain the VRF ID from the given VRF iterator. */
vrf_id_t
-vrf_iter2id (vrf_iter_t iter)
+vrf_name_to_id (const char *name)
{
- struct route_node *rn = (struct route_node *) iter;
- return (rn && rn->info) ? ((struct vrf *)rn->info)->vrf_id : VRF_DEFAULT;
-}
+ struct vrf *vrf;
+ vrf_id_t vrf_id = VRF_DEFAULT; //Pending: need a way to return invalid id/ routine not used.
-/* Obtain the data pointer from the given VRF iterator. */
-void *
-vrf_iter2info (vrf_iter_t iter)
-{
- struct route_node *rn = (struct route_node *) iter;
- return (rn && rn->info) ? ((struct vrf *)rn->info)->info : NULL;
-}
+ vrf = vrf_lookup_by_name (name);
+ if (vrf)
+ vrf_id = vrf->vrf_id;
-/* Obtain the interface list from the given VRF iterator. */
-struct list *
-vrf_iter2iflist (vrf_iter_t iter)
-{
- struct route_node *rn = (struct route_node *) iter;
- return (rn && rn->info) ? ((struct vrf *)rn->info)->iflist : NULL;
+ 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);
+ struct vrf *vrf = vrf_get (vrf_id, NULL);
return vrf->info;
}
void *
vrf_info_lookup (vrf_id_t vrf_id)
{
- struct vrf *vrf = vrf_lookup (vrf_id);
+ struct vrf *vrf = vrf_lookup_by_id (vrf_id);
return vrf ? vrf->info : NULL;
}
struct list *
vrf_iflist (vrf_id_t vrf_id)
{
- struct vrf * vrf = vrf_lookup (vrf_id);
+ struct vrf * vrf = vrf_lookup_by_id (vrf_id);
return vrf ? vrf->iflist : NULL;
}
struct list *
vrf_iflist_get (vrf_id_t vrf_id)
{
- struct vrf * vrf = vrf_get (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 || vrf_id == VRF_UNKNOWN)
+ 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 || vrf_id == VRF_UNKNOWN ||
+ 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 || vrf_id == VRF_UNKNOWN ||
+ 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;
- /* Allocate VRF table. */
- vrf_table = route_table_init ();
+ if (debug_vrf)
+ zlog_debug ("%s: Initializing VRF subsystem", __PRETTY_FUNCTION__);
/* The default VRF always exists. */
- default_vrf = vrf_get (VRF_DEFAULT);
+ default_vrf = vrf_get (VRF_DEFAULT, VRF_DEFAULT_NAME);
if (!default_vrf)
{
zlog_err ("vrf_init: failed to create the default VRF!");
exit (1);
}
- /* Set the default VRF name. */
- default_vrf->name = XSTRDUP (MTYPE_VRF_NAME, VRF_DEFAULT_NAME);
-
/* Enable the default VRF. */
if (!vrf_enable (default_vrf))
{
void
vrf_terminate (void)
{
- struct route_node *rn;
struct vrf *vrf;
- for (rn = route_top (vrf_table); rn; rn = route_next (rn))
- if ((vrf = rn->info) != NULL)
- vrf_delete (vrf);
+ if (debug_vrf)
+ zlog_debug ("%s: Shutting down vrf subsystem", __PRETTY_FUNCTION__);
- route_table_finish (vrf_table);
- vrf_table = NULL;
+ 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 ret = -1;
- if (!vrf_is_enabled (vrf_lookup (vrf_id)))
+ ret = socket (domain, type, protocol);
+
+ return ret;
+}
+
+/* vrf CLI commands */
+DEFUN_NOSH (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;
+
+ if (strlen(vrfname) > VRF_NAMSIZ)
{
- errno = ENOSYS;
- return -1;
+ vty_out (vty, "%% VRF name %s is invalid: length exceeds "
+ "%d characters%s",
+ vrfname, VRF_NAMSIZ, VTY_NEWLINE);
+ return CMD_WARNING;
}
- if (vrf_id == VRF_DEFAULT)
- ret = socket (domain, type, protocol);
- else
- errno = ENOSYS;
+ vrfp = vrf_get (VRF_UNKNOWN, vrfname);
- return ret;
+ VTY_PUSH_CONTEXT (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;
+}
+
+
+struct cmd_node vrf_node =
+{
+ VRF_NODE,
+ "%s(config-vrf)# ",
+ 1
+};
+
+/*
+ * 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);
+}
+
+void
+vrf_cmd_init (int (*writefunc)(struct vty *vty))
+{
+ install_element (CONFIG_NODE, &vrf_cmd);
+ install_element (CONFIG_NODE, &no_vrf_cmd);
+ install_node (&vrf_node, writefunc);
+ install_default (VRF_NODE);
+}
projects / mirror_frr.git / blobdiff