/*
* lib/route/neigh.c Neighbours
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation version 2.1
* of the License.
*
* Copyright (c) 2003-2006 Thomas Graf <tgraf@suug.ch>
*/
/**
* @ingroup rtnl
* @defgroup neigh Neighbours
* @brief
*
* The neighbour table establishes bindings between protocol addresses and
* link layer addresses for hosts sharing the same physical link. This
* module allows you to access and manipulate the content of these tables.
*
* @par Neighbour States
* @code
* NUD_INCOMPLETE
* NUD_REACHABLE
* NUD_STALE
* NUD_DELAY
* NUD_PROBE
* NUD_FAILED
* NUD_NOARP
* NUD_PERMANENT
* @endcode
*
* @par Neighbour Flags
* @code
* NTF_PROXY
* NTF_ROUTER
* @endcode
*
* @par Neighbour Identification
* A neighbour is uniquely identified by the attributes listed below, whenever
* you refer to an existing neighbour all of the attributes must be set.
* Neighbours from caches automatically have all required attributes set.
* - interface index (rtnl_neigh_set_ifindex())
* - destination address (rtnl_neigh_set_dst())
*
* @par Changeable Attributes
* \anchor neigh_changeable
* - state (rtnl_neigh_set_state())
* - link layer address (rtnl_neigh_set_lladdr())
*
* @par Required Caches for Dumping
* In order to dump neighbour attributes you must provide the following
* caches via nl_cache_provide()
* - link cache holding all links
*
* @par TODO
* - Document proxy settings
* - Document states and their influence
*
* @par 1) Retrieving information about configured neighbours
* @code
* // The first step is to retrieve a list of all available neighbour within
* // the kernel and put them into a cache.
* struct nl_cache *cache = rtnl_neigh_alloc_cache(handle);
*
* // Neighbours can then be looked up by the interface and destination
* // address:
* struct rtnl_neigh *neigh = rtnl_neigh_get(cache, ifindex, dst_addr);
*
* // After successful usage, the object must be given back to the cache
* rtnl_neigh_put(neigh);
* @endcode
*
* @par 2) Adding new neighbours
* @code
* // Allocate an empty neighbour handle to be filled out with the attributes
* // of the new neighbour.
* struct rtnl_neigh *neigh = rtnl_neigh_alloc();
*
* // Fill out the attributes of the new neighbour
* rtnl_neigh_set_ifindex(neigh, ifindex);
* rtnl_neigh_set_dst(neigh, dst_addr);
* rtnl_neigh_set_state(neigh, rtnl_neigh_str2state("permanent"));
*
* // Build the netlink message and send it to the kernel, the operation will
* // block until the operation has been completed. Alternatively the required
* // netlink message can be built using rtnl_neigh_build_add_request()
* // to be sent out using nl_send_auto_complete().
* rtnl_neigh_add(nl_handle, neigh, NLM_F_REPLACE);
*
* // Free the memory
* rtnl_neigh_put(neigh);
* @endcode
*
* @par 3) Deleting an existing neighbour
* @code
* // Allocate an empty neighbour object to be filled out with the attributes
* // matching the neighbour to be deleted. Alternatively a fully equipped
* // neighbour object out of a cache can be used instead.
* struct rtnl_neigh *neigh = rtnl_neigh_alloc();
*
* // Neighbours are uniquely identified by their interface index and
* // destination address, you may fill out other attributes but they
* // will have no influence.
* rtnl_neigh_set_ifindex(neigh, ifindex);
* rtnl_neigh_set_dst(neigh, dst_addr);
*
* // Build the netlink message and send it to the kernel, the operation will
* // block until the operation has been completed. Alternatively the required
* // netlink message can be built using rtnl_neigh_build_delete_request()
* // to be sent out using nl_send_auto_complete().
* rtnl_neigh_delete(handle, neigh, 0);
*
* // Free the memory
* rtnl_neigh_put(neigh);
* @endcode
*
* @par 4) Changing neighbour attributes
* @code
* // Allocate an empty neighbour object to be filled out with the attributes
* // matching the neighbour to be changed and the new parameters. Alternatively
* // a fully equipped modified neighbour object out of a cache can be used.
* struct rtnl_neigh *neigh = rtnl_neigh_alloc();
*
* // Identify the neighbour to be changed by its interface index and
* // destination address
* rtnl_neigh_set_ifindex(neigh, ifindex);
* rtnl_neigh_set_dst(neigh, dst_addr);
*
* // The link layer address may be modified, if so it is wise to change
* // its state to "permanent" in order to avoid having it overwritten.
* rtnl_neigh_set_lladdr(neigh, lladdr);
*
* // Secondly the state can be modified allowing normal neighbours to be
* // converted into permanent entries or to manually confirm a neighbour.
* rtnl_neigh_set_state(neigh, state);
*
* // Build the netlink message and send it to the kernel, the operation will
* // block until the operation has been completed. Alternatively the required
* // netlink message can be built using rtnl_neigh_build_change_request()
* // to be sent out using nl_send_auto_complete().
* rtnl_neigh_change(handle, neigh, 0);
*
* // Free the memory
* rtnl_neigh_put(neigh);
* @endcode
* @{
*/
#include <netlink-local.h>
#include <netlink/netlink.h>
#include <netlink/utils.h>
#include <netlink/route/rtnl.h>
#include <netlink/route/neighbour.h>
#include <netlink/route/link.h>
/** @cond SKIP */
#define NEIGH_ATTR_FLAGS 0x01
#define NEIGH_ATTR_STATE 0x02
#define NEIGH_ATTR_LLADDR 0x04
#define NEIGH_ATTR_DST 0x08
#define NEIGH_ATTR_CACHEINFO 0x10
#define NEIGH_ATTR_IFINDEX 0x20
#define NEIGH_ATTR_FAMILY 0x40
#define NEIGH_ATTR_TYPE 0x80
#define NEIGH_ATTR_PROBES 0x100
static struct nl_cache_ops rtnl_neigh_ops;
static struct nl_object_ops neigh_obj_ops;
/** @endcond */
static void neigh_free_data(struct nl_object *c)
{
struct rtnl_neigh *neigh = nl_object_priv(c);
if (!neigh)
return;
nl_addr_put(neigh->n_lladdr);
nl_addr_put(neigh->n_dst);
}
static int neigh_clone(struct nl_object *_dst, struct nl_object *_src)
{
struct rtnl_neigh *dst = nl_object_priv(_dst);
struct rtnl_neigh *src = nl_object_priv(_src);
if (src->n_lladdr)
if (!(dst->n_lladdr = nl_addr_clone(src->n_lladdr)))
goto errout;
if (src->n_dst)
if (!(dst->n_dst = nl_addr_clone(src->n_dst)))
goto errout;
return 0;
errout:
return nl_get_errno();
}
static int neigh_compare(struct nl_object *_a, struct nl_object *_b,
uint32_t attrs, int flags)
{
struct rtnl_neigh *a = (struct rtnl_neigh *) _a;
struct rtnl_neigh *b = (struct rtnl_neigh *) _b;
int diff = 0;
#define NEIGH_DIFF(ATTR, EXPR) ATTR_DIFF(attrs, NEIGH_ATTR_##ATTR, a, b, EXPR)
diff |= NEIGH_DIFF(IFINDEX, a->n_ifindex != b->n_ifindex);
diff |= NEIGH_DIFF(FAMILY, a->n_family != b->n_family);
diff |= NEIGH_DIFF(TYPE, a->n_type != b->n_type);
diff |= NEIGH_DIFF(LLADDR, nl_addr_cmp(a->n_lladdr, b->n_lladdr));
diff |= NEIGH_DIFF(DST, nl_addr_cmp(a->n_dst, b->n_dst));
if (flags & LOOSE_FLAG_COMPARISON) {
diff |= NEIGH_DIFF(STATE,
(a->n_state ^ b->n_state) & b->n_state_mask);
diff |= NEIGH_DIFF(FLAGS,
(a->n_flags ^ b->n_flags) & b->n_flag_mask);
} else {
diff |= NEIGH_DIFF(STATE, a->n_state != b->n_state);
diff |= NEIGH_DIFF(FLAGS, a->n_flags != b->n_flags);
}
#undef NEIGH_DIFF
return diff;
}
static struct trans_tbl neigh_attrs[] = {
__ADD(NEIGH_ATTR_FLAGS, flags)
__ADD(NEIGH_ATTR_STATE, state)
__ADD(NEIGH_ATTR_LLADDR, lladdr)
__ADD(NEIGH_ATTR_DST, dst)
__ADD(NEIGH_ATTR_CACHEINFO, cacheinfo)
__ADD(NEIGH_ATTR_IFINDEX, ifindex)
__ADD(NEIGH_ATTR_FAMILY, family)
__ADD(NEIGH_ATTR_TYPE, type)
__ADD(NEIGH_ATTR_PROBES, probes)
};
static char *neigh_attrs2str(int attrs, char *buf, size_t len)
{
return __flags2str(attrs, buf, len, neigh_attrs,
ARRAY_SIZE(neigh_attrs));
}
static struct nla_policy neigh_policy[NDA_MAX+1] = {
[NDA_CACHEINFO] = { .minlen = sizeof(struct nda_cacheinfo) },
[NDA_PROBES] = { .type = NLA_U32 },
};
static int neigh_msg_parser(struct nl_cache_ops *ops, struct sockaddr_nl *who,
struct nlmsghdr *n, struct nl_parser_param *pp)
{
struct rtnl_neigh *neigh;
struct nlattr *tb[NDA_MAX + 1];
struct ndmsg *nm;
int err;
neigh = rtnl_neigh_alloc();
if (!neigh) {
err = nl_errno(ENOMEM);
goto errout;
}
neigh->ce_msgtype = n->nlmsg_type;
nm = nlmsg_data(n);
err = nlmsg_parse(n, sizeof(*nm), tb, NDA_MAX, neigh_policy);
if (err < 0)
goto errout;
neigh->n_family = nm->ndm_family;
neigh->n_ifindex = nm->ndm_ifindex;
neigh->n_state = nm->ndm_state;
neigh->n_flags = nm->ndm_flags;
neigh->n_type = nm->ndm_type;
neigh->ce_mask |= (NEIGH_ATTR_FAMILY | NEIGH_ATTR_IFINDEX |
NEIGH_ATTR_STATE | NEIGH_ATTR_FLAGS |
NEIGH_ATTR_TYPE);
if (tb[NDA_LLADDR]) {
neigh->n_lladdr = nla_get_addr(tb[NDA_LLADDR], AF_UNSPEC);
if (!neigh->n_lladdr)
goto errout;
nl_addr_set_family(neigh->n_lladdr,
nl_addr_guess_family(neigh->n_lladdr));
neigh->ce_mask |= NEIGH_ATTR_LLADDR;
}
if (tb[NDA_DST]) {
neigh->n_dst = nla_get_addr(tb[NDA_DST], neigh->n_family);
if (!neigh->n_dst)
goto errout;
neigh->ce_mask |= NEIGH_ATTR_DST;
}
if (tb[NDA_CACHEINFO]) {
struct nda_cacheinfo *ci = nla_data(tb[NDA_CACHEINFO]);
neigh->n_cacheinfo.nci_confirmed = ci->ndm_confirmed;
neigh->n_cacheinfo.nci_used = ci->ndm_used;
neigh->n_cacheinfo.nci_updated = ci->ndm_updated;
neigh->n_cacheinfo.nci_refcnt = ci->ndm_refcnt;
neigh->ce_mask |= NEIGH_ATTR_CACHEINFO;
}
if (tb[NDA_PROBES]) {
neigh->n_probes = nla_get_u32(tb[NDA_PROBES]);
neigh->ce_mask |= NEIGH_ATTR_PROBES;
}
err = pp->pp_cb((struct nl_object *) neigh, pp);
if (err < 0)
goto errout;
err = P_ACCEPT;
errout:
rtnl_neigh_put(neigh);
return err;
}
static int neigh_request_update(struct nl_cache *c, struct nl_handle *h)
{
return nl_rtgen_request(h, RTM_GETNEIGH, AF_UNSPEC, NLM_F_DUMP);
}
static int neigh_dump_brief(struct nl_object *a, struct nl_dump_params *p)
{
char dst[INET6_ADDRSTRLEN+5], lladdr[INET6_ADDRSTRLEN+5];
struct rtnl_neigh *n = (struct rtnl_neigh *) a;
struct nl_cache *link_cache;
char state[128], flags[64];
link_cache = nl_cache_mngt_require("route/link");
dp_dump(p, "%s ", nl_addr2str(n->n_dst, dst, sizeof(dst)));
if (link_cache)
dp_dump(p, "dev %s ",
rtnl_link_i2name(link_cache, n->n_ifindex,
state, sizeof(state)));
else
dp_dump(p, "dev %d ", n->n_ifindex);
if (n->ce_mask & NEIGH_ATTR_LLADDR)
dp_dump(p, "lladdr %s ",
nl_addr2str(n->n_lladdr, lladdr, sizeof(lladdr)));
rtnl_neigh_state2str(n->n_state, state, sizeof(state));
rtnl_neigh_flags2str(n->n_flags, flags, sizeof(flags));
if (state[0])
dp_dump(p, "<%s", state);
if (flags[0])
dp_dump(p, "%s%s", state[0] ? "," : "<", flags);
if (state[0] || flags[0])
dp_dump(p, ">");
dp_dump(p, "\n");
return 1;
}
static int neigh_dump_full(struct nl_object *a, struct nl_dump_params *p)
{
char rtn_type[32];
struct rtnl_neigh *n = (struct rtnl_neigh *) a;
int hz = nl_get_hz();
int line = neigh_dump_brief(a, p);
dp_dump_line(p, line++, " refcnt %u type %s confirmed %u used "
"%u updated %u\n",
n->n_cacheinfo.nci_refcnt,
nl_rtntype2str(n->n_type, rtn_type, sizeof(rtn_type)),
n->n_cacheinfo.nci_confirmed/hz,
n->n_cacheinfo.nci_used/hz, n->n_cacheinfo.nci_updated/hz);
return line;
}
static int neigh_dump_stats(struct nl_object *a, struct nl_dump_params *p)
{
return neigh_dump_full(a, p);
}
static int neigh_dump_xml(struct nl_object *obj, struct nl_dump_params *p)
{
struct rtnl_neigh *neigh = (struct rtnl_neigh *) obj;
char buf[128];
int line = 0;
dp_dump_line(p, line++, "<neighbour>\n");
dp_dump_line(p, line++, " <family>%s</family>\n",
nl_af2str(neigh->n_family, buf, sizeof(buf)));
if (neigh->ce_mask & NEIGH_ATTR_LLADDR)
dp_dump_line(p, line++, " <lladdr>%s</lladdr>\n",
nl_addr2str(neigh->n_lladdr, buf, sizeof(buf)));
if (neigh->ce_mask & NEIGH_ATTR_DST)
dp_dump_line(p, line++, " <dst>%s</dst>\n",
nl_addr2str(neigh->n_dst, buf, sizeof(buf)));
if (neigh->ce_mask & NEIGH_ATTR_IFINDEX) {
struct nl_cache *link_cache;
link_cache = nl_cache_mngt_require("route/link");
if (link_cache)
dp_dump_line(p, line++, " <device>%s</device>\n",
rtnl_link_i2name(link_cache,
neigh->n_ifindex,
buf, sizeof(buf)));
else
dp_dump_line(p, line++, " <device>%u</device>\n",
neigh->n_ifindex);
}
if (neigh->ce_mask & NEIGH_ATTR_PROBES)
dp_dump_line(p, line++, " <probes>%u</probes>\n",
neigh->n_probes);
if (neigh->ce_mask & NEIGH_ATTR_TYPE)
dp_dump_line(p, line++, " <type>%s</type>\n",
nl_rtntype2str(neigh->n_type, buf, sizeof(buf)));
rtnl_neigh_flags2str(neigh->n_flags, buf, sizeof(buf));
if (buf[0])
dp_dump_line(p, line++, " <flags>%s</flags>\n", buf);
rtnl_neigh_state2str(neigh->n_state, buf, sizeof(buf));
if (buf[0])
dp_dump_line(p, line++, " <state>%s</state>\n", buf);
dp_dump_line(p, line++, "</neighbour>\n");
#if 0
struct rtnl_ncacheinfo n_cacheinfo;
#endif
return line;
}
static int neigh_dump_env(struct nl_object *obj, struct nl_dump_params *p)
{
struct rtnl_neigh *neigh = (struct rtnl_neigh *) obj;
char buf[128];
int line = 0;
dp_dump_line(p, line++, "NEIGH_FAMILY=%s\n",
nl_af2str(neigh->n_family, buf, sizeof(buf)));
if (neigh->ce_mask & NEIGH_ATTR_LLADDR)
dp_dump_line(p, line++, "NEIGHT_LLADDR=%s\n",
nl_addr2str(neigh->n_lladdr, buf, sizeof(buf)));
if (neigh->ce_mask & NEIGH_ATTR_DST)
dp_dump_line(p, line++, "NEIGH_DST=%s\n",
nl_addr2str(neigh->n_dst, buf, sizeof(buf)));
if (neigh->ce_mask & NEIGH_ATTR_IFINDEX) {
struct nl_cache *link_cache;
dp_dump_line(p, line++, "NEIGH_IFINDEX=%u\n",
neigh->n_ifindex);
link_cache = nl_cache_mngt_require("route/link");
if (link_cache)
dp_dump_line(p, line++, "NEIGH_IFNAME=%s\n",
rtnl_link_i2name(link_cache,
neigh->n_ifindex,
buf, sizeof(buf)));
}
if (neigh->ce_mask & NEIGH_ATTR_PROBES)
dp_dump_line(p, line++, "NEIGH_PROBES=%u\n",
neigh->n_probes);
if (neigh->ce_mask & NEIGH_ATTR_TYPE)
dp_dump_line(p, line++, "NEIGH_TYPE=%s\n",
nl_rtntype2str(neigh->n_type, buf, sizeof(buf)));
rtnl_neigh_flags2str(neigh->n_flags, buf, sizeof(buf));
if (buf[0])
dp_dump_line(p, line++, "NEIGH_FLAGS=%s\n", buf);
rtnl_neigh_state2str(neigh->n_state, buf, sizeof(buf));
if (buf[0])
dp_dump_line(p, line++, "NEIGH_STATE=%s\n", buf);
return line;
}
/**
* @name Neighbour Object Allocation/Freeage
* @{
*/
struct rtnl_neigh *rtnl_neigh_alloc(void)
{
return (struct rtnl_neigh *) nl_object_alloc(&neigh_obj_ops);
}
void rtnl_neigh_put(struct rtnl_neigh *neigh)
{
nl_object_put((struct nl_object *) neigh);
}
/** @} */
/**
* @name Neighbour Cache Managament
* @{
*/
/**
* Build a neighbour cache including all neighbours currently configured in the kernel.
* @arg handle netlink handle
*
* Allocates a new neighbour cache, initializes it properly and updates it
* to include all neighbours currently configured in the kernel.
*
* @note The caller is responsible for destroying and freeing the
* cache after using it.
* @return The new cache or NULL if an error occured.
*/
struct nl_cache *rtnl_neigh_alloc_cache(struct nl_handle *handle)
{
struct nl_cache *cache;
cache = nl_cache_alloc(&rtnl_neigh_ops);
if (cache == NULL)
return NULL;
if (handle && nl_cache_refill(handle, cache) < 0) {
nl_cache_free(cache);
return NULL;
}
NL_DBG(2, "Returning new cache %p\n", cache);
return cache;
}
/**
* Look up a neighbour by interface index and destination address
* @arg cache neighbour cache
* @arg ifindex interface index the neighbour is on
* @arg dst destination address of the neighbour
* @return neighbour handle or NULL if no match was found.
*/
struct rtnl_neigh * rtnl_neigh_get(struct nl_cache *cache, int ifindex,
struct nl_addr *dst)
{
struct rtnl_neigh *neigh;
nl_list_for_each_entry(neigh, &cache->c_items, ce_list) {
if (neigh->n_ifindex == ifindex &&
!nl_addr_cmp(neigh->n_dst, dst)) {
nl_object_get((struct nl_object *) neigh);
return neigh;
}
}
return NULL;
}
/** @} */
/**
* @name Neighbour Addition
* @{
*/
static struct nl_msg * build_neigh_msg(struct rtnl_neigh *tmpl, int cmd,
int flags)
{
struct nl_msg *msg;
struct ndmsg nhdr = {
.ndm_ifindex = tmpl->n_ifindex,
.ndm_family = nl_addr_get_family(tmpl->n_dst),
.ndm_state = NUD_PERMANENT,
};
if (tmpl->ce_mask & NEIGH_ATTR_STATE)
nhdr.ndm_state = tmpl->n_state;
msg = nlmsg_alloc_simple(cmd, flags);
if (!msg)
return NULL;
if (nlmsg_append(msg, &nhdr, sizeof(nhdr), NLMSG_ALIGNTO) < 0)
goto nla_put_failure;
NLA_PUT_ADDR(msg, NDA_DST, tmpl->n_dst);
if (tmpl->ce_mask & NEIGH_ATTR_LLADDR)
NLA_PUT_ADDR(msg, NDA_LLADDR, tmpl->n_lladdr);
return msg;
nla_put_failure:
nlmsg_free(msg);
return NULL;
}
/**
* Build netlink request message to add a new neighbour
* @arg tmpl template with data of new neighbour
* @arg flags additional netlink message flags
*
* Builds a new netlink message requesting a addition of a new
* neighbour. The netlink message header isn't fully equipped with
* all relevant fields and must thus be sent out via nl_send_auto_complete()
* or supplemented as needed. \a tmpl must contain the attributes of the new
* neighbour set via \c rtnl_neigh_set_* functions.
*
* The following attributes must be set in the template:
* - Interface index (rtnl_neigh_set_ifindex())
* - State (rtnl_neigh_set_state())
* - Destination address (rtnl_neigh_set_dst())
* - Link layer address (rtnl_neigh_set_lladdr())
*
* @return The netlink message
*/
struct nl_msg * rtnl_neigh_build_add_request(struct rtnl_neigh *tmpl, int flags)
{
return build_neigh_msg(tmpl, RTM_NEWNEIGH, NLM_F_CREATE | flags);
}
/**
* Add a new neighbour
* @arg handle netlink handle
* @arg tmpl template with requested changes
* @arg flags additional netlink message flags
*
* Builds a netlink message by calling rtnl_neigh_build_add_request(),
* sends the request to the kernel and waits for the next ACK to be
* received and thus blocks until the request has been fullfilled.
*
* The following attributes must be set in the template:
* - Interface index (rtnl_neigh_set_ifindex())
* - State (rtnl_neigh_set_state())
* - Destination address (rtnl_neigh_set_dst())
* - Link layer address (rtnl_neigh_set_lladdr())
*
* @return 0 on sucess or a negative error if an error occured.
*/
int rtnl_neigh_add(struct nl_handle *handle, struct rtnl_neigh *tmpl, int flags)
{
int err;
struct nl_msg *msg;
msg = rtnl_neigh_build_add_request(tmpl, flags);
if (!msg)
return nl_errno(ENOMEM);
err = nl_send_auto_complete(handle, msg);
if (err < 0)
return err;
nlmsg_free(msg);
return nl_wait_for_ack(handle);
}
/** @} */
/**
* @name Neighbour Deletion
* @{
*/
/**
* Build a netlink request message to delete a neighbour
* @arg neigh neighbour to delete
* @arg flags additional netlink message flags
*
* Builds a new netlink message requesting a deletion of a neighbour.
* The netlink message header isn't fully equipped with all relevant
* fields and must thus be sent out via nl_send_auto_complete()
* or supplemented as needed. \a neigh must point to an existing
* neighbour.
*
* @return The netlink message
*/
struct nl_msg *rtnl_neigh_build_delete_request(struct rtnl_neigh *neigh,
int flags)
{
return build_neigh_msg(neigh, RTM_DELNEIGH, flags);
}
/**
* Delete a neighbour
* @arg handle netlink handle
* @arg neigh neighbour to delete
* @arg flags additional netlink message flags
*
* Builds a netlink message by calling rtnl_neigh_build_delete_request(),
* sends the request to the kernel and waits for the next ACK to be
* received and thus blocks until the request has been fullfilled.
*
* @return 0 on sucess or a negative error if an error occured.
*/
int rtnl_neigh_delete(struct nl_handle *handle, struct rtnl_neigh *neigh,
int flags)
{
int err;
struct nl_msg *msg;
msg = rtnl_neigh_build_delete_request(neigh, flags);
if (!msg)
return nl_errno(ENOMEM);
err = nl_send_auto_complete(handle, msg);
if (err < 0)
return err;
nlmsg_free(msg);
return nl_wait_for_ack(handle);
}
/** @} */
/**
* @name Neighbour Modification
* @{
*/
/**
* Build a netlink request message to change neighbour attributes
* @arg neigh the neighbour to change
* @arg flags additional netlink message flags
*
* Builds a new netlink message requesting a change of a neigh
* attributes. The netlink message header isn't fully equipped with
* all relevant fields and must thus be sent out via nl_send_auto_complete()
* or supplemented as needed.
*
* @return The netlink message
* @note Not all attributes can be changed, see
* \ref neigh_changeable "Changeable Attributes" for a list.
*/
struct nl_msg *rtnl_neigh_build_change_request(struct rtnl_neigh *neigh,
int flags)
{
return build_neigh_msg(neigh, RTM_NEWNEIGH, NLM_F_REPLACE | flags);
}
/**
* Change neighbour attributes
* @arg handle netlink handle
* @arg neigh neighbour to be changed
* @arg flags additional netlink message flags
*
* Builds a netlink message by calling rtnl_neigh_build_change_request(),
* sends the request to the kernel and waits for the next ACK to be
* received and thus blocks until the request has been fullfilled.
*
* @return 0 on sucess or a negative error if an error occured.
* @note Not all attributes can be changed, see
* \ref neigh_changeable "Changeable Attributes" for a list.
*/
int rtnl_neigh_change(struct nl_handle *handle, struct rtnl_neigh *neigh,
int flags)
{
int err;
struct nl_msg *msg;
msg = rtnl_neigh_build_change_request(neigh, flags);
if (!msg)
return nl_errno(ENOMEM);
err = nl_send_auto_complete(handle, msg);
if (err < 0)
return err;
nlmsg_free(msg);
return nl_wait_for_ack(handle);
}
/** @} */
/**
* @name Neighbour States Translations
* @{
*/
static struct trans_tbl neigh_states[] = {
__ADD(NUD_INCOMPLETE, incomplete)
__ADD(NUD_REACHABLE, reachable)
__ADD(NUD_STALE, stale)
__ADD(NUD_DELAY, delay)
__ADD(NUD_PROBE, probe)
__ADD(NUD_FAILED, failed)
__ADD(NUD_NOARP, norarp)
__ADD(NUD_PERMANENT, permanent)
};
char * rtnl_neigh_state2str(int state, char *buf, size_t len)
{
return __flags2str(state, buf, len, neigh_states,
ARRAY_SIZE(neigh_states));
}
int rtnl_neigh_str2state(const char *name)
{
return __str2type(name, neigh_states, ARRAY_SIZE(neigh_states));
}
/** @} */
/**
* @name Neighbour Flags Translations
* @{
*/
static struct trans_tbl neigh_flags[] = {
__ADD(NTF_PROXY, proxy)
__ADD(NTF_ROUTER, router)
};
char * rtnl_neigh_flags2str(int flags, char *buf, size_t len)
{
return __flags2str(flags, buf, len, neigh_flags,
ARRAY_SIZE(neigh_flags));
}
int rtnl_neigh_str2flag(const char *name)
{
return __str2type(name, neigh_flags, ARRAY_SIZE(neigh_flags));
}
/** @} */
/**
* @name Attributes
* @{
*/
void rtnl_neigh_set_state(struct rtnl_neigh *neigh, int state)
{
neigh->n_state_mask |= state;
neigh->n_state |= state;
neigh->ce_mask |= NEIGH_ATTR_STATE;
}
int rtnl_neigh_get_state(struct rtnl_neigh *neigh)
{
if (neigh->ce_mask & NEIGH_ATTR_STATE)
return neigh->n_state;
else
return -1;
}
void rtnl_neigh_unset_state(struct rtnl_neigh *neigh, int state)
{
neigh->n_state_mask |= state;
neigh->n_state &= ~state;
neigh->ce_mask |= NEIGH_ATTR_STATE;
}
void rtnl_neigh_set_flags(struct rtnl_neigh *neigh, unsigned int flags)
{
neigh->n_flag_mask |= flags;
neigh->n_flags |= flags;
neigh->ce_mask |= NEIGH_ATTR_FLAGS;
}
unsigned int rtnl_neigh_get_flags(struct rtnl_neigh *neigh)
{
return neigh->n_flags;
}
void rtnl_neigh_unset_flags(struct rtnl_neigh *neigh, unsigned int flags)
{
neigh->n_flag_mask |= flags;
neigh->n_flags &= ~flags;
neigh->ce_mask |= NEIGH_ATTR_FLAGS;
}
void rtnl_neigh_set_ifindex(struct rtnl_neigh *neigh, int ifindex)
{
neigh->n_ifindex = ifindex;
neigh->ce_mask |= NEIGH_ATTR_IFINDEX;
}
int rtnl_neigh_get_ifindex(struct rtnl_neigh *neigh)
{
if (neigh->ce_mask & NEIGH_ATTR_IFINDEX)
return neigh->n_ifindex;
else
return RTNL_LINK_NOT_FOUND;
}
static inline int __assign_addr(struct rtnl_neigh *neigh, struct nl_addr **pos,
struct nl_addr *new, int flag, int nocheck)
{
if (!nocheck) {
if (neigh->ce_mask & NEIGH_ATTR_FAMILY) {
if (new->a_family != neigh->n_family)
return nl_error(EINVAL,
"Address family mismatch");
} else {
neigh->n_family = new->a_family;
neigh->ce_mask |= NEIGH_ATTR_FAMILY;
}
}
if (*pos)
nl_addr_put(*pos);
nl_addr_get(new);
*pos = new;
neigh->ce_mask |= flag;
return 0;
}
void rtnl_neigh_set_lladdr(struct rtnl_neigh *neigh, struct nl_addr *addr)
{
__assign_addr(neigh, &neigh->n_lladdr, addr, NEIGH_ATTR_LLADDR, 1);
}
struct nl_addr *rtnl_neigh_get_lladdr(struct rtnl_neigh *neigh)
{
if (neigh->ce_mask & NEIGH_ATTR_LLADDR)
return neigh->n_lladdr;
else
return NULL;
}
int rtnl_neigh_set_dst(struct rtnl_neigh *neigh, struct nl_addr *addr)
{
return __assign_addr(neigh, &neigh->n_dst, addr,
NEIGH_ATTR_DST, 0);
}
struct nl_addr *rtnl_neigh_get_dst(struct rtnl_neigh *neigh)
{
if (neigh->ce_mask & NEIGH_ATTR_DST)
return neigh->n_dst;
else
return NULL;
}
void rtnl_neigh_set_family(struct rtnl_neigh *neigh, int family)
{
neigh->n_family = family;
neigh->ce_mask |= NEIGH_ATTR_FAMILY;
}
void rtnl_neigh_set_type(struct rtnl_neigh *neigh, int type)
{
neigh->n_type = type;
neigh->ce_mask = NEIGH_ATTR_TYPE;
}
int rtnl_neigh_get_type(struct rtnl_neigh *neigh)
{
if (neigh->ce_mask & NEIGH_ATTR_TYPE)
return neigh->n_type;
else
return -1;
}
/** @} */
static struct nl_object_ops neigh_obj_ops = {
.oo_name = "route/neigh",
.oo_size = sizeof(struct rtnl_neigh),
.oo_free_data = neigh_free_data,
.oo_clone = neigh_clone,
.oo_dump[NL_DUMP_BRIEF] = neigh_dump_brief,
.oo_dump[NL_DUMP_FULL] = neigh_dump_full,
.oo_dump[NL_DUMP_STATS] = neigh_dump_stats,
.oo_dump[NL_DUMP_XML] = neigh_dump_xml,
.oo_dump[NL_DUMP_ENV] = neigh_dump_env,
.oo_compare = neigh_compare,
.oo_attrs2str = neigh_attrs2str,
.oo_id_attrs = (NEIGH_ATTR_DST | NEIGH_ATTR_FAMILY),
};
static struct nl_af_group neigh_groups[] = {
{ AF_UNSPEC, RTNLGRP_NEIGH },
{ END_OF_GROUP_LIST },
};
static struct nl_cache_ops rtnl_neigh_ops = {
.co_name = "route/neigh",
.co_hdrsize = sizeof(struct ndmsg),
.co_msgtypes = {
{ RTM_NEWNEIGH, NL_ACT_NEW, "new" },
{ RTM_DELNEIGH, NL_ACT_DEL, "del" },
{ RTM_GETNEIGH, NL_ACT_GET, "get" },
END_OF_MSGTYPES_LIST,
},
.co_protocol = NETLINK_ROUTE,
.co_groups = neigh_groups,
.co_request_update = neigh_request_update,
.co_msg_parser = neigh_msg_parser,
.co_obj_ops = &neigh_obj_ops,
};
static void __init neigh_init(void)
{
nl_cache_mngt_register(&rtnl_neigh_ops);
}
static void __exit neigh_exit(void)
{
nl_cache_mngt_unregister(&rtnl_neigh_ops);
}
/** @} */