X-Git-Url: http://git.onelab.eu/?p=libnl.git;a=blobdiff_plain;f=lib%2Froute%2Fneigh.c;fp=lib%2Froute%2Fneigh.c;h=e8e0e40cfc88144a68a2cd8ff3f13559314fb50c;hp=0000000000000000000000000000000000000000;hb=4cee2ecb3b8afa0637e6f5fe4c57985a4bc740ff;hpb=2df2fbe518d5a221ce6e3ee88a3fb23fb1b94b27 diff --git a/lib/route/neigh.c b/lib/route/neigh.c new file mode 100644 index 0000000..e8e0e40 --- /dev/null +++ b/lib/route/neigh.c @@ -0,0 +1,1115 @@ +/* + * 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 + */ + +/** + * @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 +#include +#include +#include +#include +#include + +/** @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; +/** @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_filter(struct nl_object *obj, struct nl_object *filter) +{ + struct rtnl_neigh *o = (struct rtnl_neigh *) obj; + struct rtnl_neigh *f = (struct rtnl_neigh *) filter; + +#define REQ(F) (f->n_mask & NEIGH_ATTR_##F) +#define AVAIL(F) (o->n_mask & NEIGH_ATTR_##F) +#define _O(F, EXPR) (REQ(F) && (!AVAIL(F) || (EXPR))) +#define _C(F, N) (REQ(F) && (!AVAIL(F) || (o->N != f->N))) + if (_C(IFINDEX, n_ifindex) || + _C(FAMILY, n_family) || + _C(TYPE, n_type) || + _O(LLADDR, nl_addr_cmp(o->n_lladdr, f->n_lladdr)) || + _O(DST, nl_addr_cmp(o->n_dst, f->n_dst)) || + _O(STATE, f->n_state ^ (o->n_state & f->n_state_mask)) || + _O(FLAGS, f->n_flags ^ (o->n_flags & f->n_flag_mask))) + return 0; +#undef REQ +#undef AVAIL +#undef _O +#undef _C + + return 1; +} + +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 sockaddr_nl *who, struct nlmsghdr *n, + void *arg) +{ + struct rtnl_neigh *neigh; + struct nlattr *tb[NDA_MAX + 1]; + struct nl_parser_param *pp = arg; + 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->n_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->n_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->n_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->n_mask |= NEIGH_ATTR_CACHEINFO; + } + + if (tb[NDA_PROBES]) { + neigh->n_probes = nla_get_u32(tb[NDA_PROBES]); + neigh->n_mask |= NEIGH_ATTR_PROBES; + } + + err = pp->pp_cb((struct nl_object *) neigh, pp); + if (err < 0) + goto errout; + + return 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->n_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++, "\n"); + dp_dump_line(p, line++, " %s\n", + nl_af2str(neigh->n_family, buf, sizeof(buf))); + + if (neigh->n_mask & NEIGH_ATTR_LLADDR) + dp_dump_line(p, line++, " %s\n", + nl_addr2str(neigh->n_lladdr, buf, sizeof(buf))); + + if (neigh->n_mask & NEIGH_ATTR_DST) + dp_dump_line(p, line++, " %s\n", + nl_addr2str(neigh->n_dst, buf, sizeof(buf))); + + if (neigh->n_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++, " %s\n", + rtnl_link_i2name(link_cache, + neigh->n_ifindex, + buf, sizeof(buf))); + else + dp_dump_line(p, line++, " %u\n", + neigh->n_ifindex); + } + + if (neigh->n_mask & NEIGH_ATTR_PROBES) + dp_dump_line(p, line++, " %u\n", + neigh->n_probes); + + if (neigh->n_mask & NEIGH_ATTR_TYPE) + dp_dump_line(p, line++, " %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++, " %s\n", buf); + + rtnl_neigh_state2str(neigh->n_state, buf, sizeof(buf)); + if (buf[0]) + dp_dump_line(p, line++, " %s\n", buf); + + dp_dump_line(p, line++, "\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->n_mask & NEIGH_ATTR_LLADDR) + dp_dump_line(p, line++, "NEIGHT_LLADDR=%s\n", + nl_addr2str(neigh->n_lladdr, buf, sizeof(buf))); + + if (neigh->n_mask & NEIGH_ATTR_DST) + dp_dump_line(p, line++, "NEIGH_DST=%s\n", + nl_addr2str(neigh->n_dst, buf, sizeof(buf))); + + if (neigh->n_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->n_mask & NEIGH_ATTR_PROBES) + dp_dump_line(p, line++, "NEIGH_PROBES=%u\n", + neigh->n_probes); + + if (neigh->n_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 + * @{ + */ + +/** + * Allocate a new neighbour object + * @return New neighbour object + */ +struct rtnl_neigh *rtnl_neigh_alloc(void) +{ + return (struct rtnl_neigh *) nl_object_alloc_from_ops(&rtnl_neigh_ops); +} + +/** + * Give back reference on neighbour object. + * @arg neigh Neighbour object to be given back. + * + * Decrements the reference counter and frees the object if the + * last reference has been released. + */ +void rtnl_neigh_put(struct rtnl_neigh *neigh) +{ + nl_object_put((struct nl_object *) neigh); +} +/** + * Free neighbour object. + * @arg neigh Neighbour object to be freed. + * + * @note Always use rtnl_neigh_put() unless you're absolutely sure + * that no other user may have a reference on this object. + */ +void rtnl_neigh_free(struct rtnl_neigh *neigh) +{ + nl_object_free((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 = nl_cache_alloc_from_ops(&rtnl_neigh_ops); + + if (cache == NULL) + return NULL; + + if (nl_cache_update(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->n_mask & NEIGH_ATTR_STATE) + nhdr.ndm_state = tmpl->n_state; + + msg = nlmsg_build_simple(cmd, flags); + if (!msg) + return NULL; + + if (nlmsg_append(msg, &nhdr, sizeof(nhdr), 1) < 0) + goto nla_put_failure; + + NLA_PUT_ADDR(msg, NDA_DST, tmpl->n_dst); + + if (tmpl->n_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) +}; + +/** + * Convert neighbour states to a character string (Reentrant). + * @arg state neighbour state + * @arg buf destination buffer + * @arg len buffer length + * + * Converts a neighbour state to a character string separated by + * commands and stores it in the specified destination buffer. + * + * @return The destination buffer + */ +char * rtnl_neigh_state2str(int state, char *buf, size_t len) +{ + return __flags2str(state, buf, len, neigh_states, + ARRAY_SIZE(neigh_states)); +} + +/** + * Convert a character string to a neighbour state + * @arg name Name of cscope + * + * Converts the provided character string specifying a neighbour + * state the corresponding numeric value. + * + * @return Neighbour state or a negative value if none was found. + */ +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) +}; + +/** + * Convert neighbour flags to a character string (Reentrant). + * @arg flags neighbour flags + * @arg buf destination buffer + * @arg len buffer length + * + * Converts neighbour flags to a character string separated by + * commands and stores it in the specified destination buffer. + * + * @return The destination buffer or a empty string if no flags are set. + */ +char * rtnl_neigh_flags2str(int flags, char *buf, size_t len) +{ + return __flags2str(flags, buf, len, neigh_flags, + ARRAY_SIZE(neigh_flags)); +} + +/** + * Convert a character string to a neighbour flag + * @arg name name of the flag + * + * Converts the provided character string specifying a neighbour + * flag the corresponding numeric value. + * + * @return Neighbour flag or a negative value if none was found. + */ +int rtnl_neigh_str2flag(const char *name) +{ + return __str2type(name, neigh_flags, ARRAY_SIZE(neigh_flags)); +} + +/** @} */ + +/** + * @name Attribute Modification + * @{ + */ + +/** + * Set a neighbour state + * @arg neigh neighbour to change + * @arg state state to set + */ +void rtnl_neigh_set_state(struct rtnl_neigh *neigh, int state) +{ + neigh->n_state_mask |= state; + neigh->n_state |= state; + neigh->n_mask |= NEIGH_ATTR_STATE; +} + +/** + * Get neighbour states + * @arg neigh neighbour handle + * @return Neighbour state or -1 if not set + */ +int rtnl_neigh_get_state(struct rtnl_neigh *neigh) +{ + if (neigh->n_mask & NEIGH_ATTR_STATE) + return neigh->n_state; + else + return -1; +} + +/** + * Unset a neigbour state + * @arg neigh neighbour to change + * @arg state state to unset + */ +void rtnl_neigh_unset_state(struct rtnl_neigh *neigh, int state) +{ + neigh->n_state_mask |= state; + neigh->n_state &= ~state; + neigh->n_mask |= NEIGH_ATTR_STATE; +} + +/** + * Set neighbour flags + * @arg neigh neighbour to change + * @arg flags flag to set + */ +void rtnl_neigh_set_flags(struct rtnl_neigh *neigh, unsigned int flags) +{ + neigh->n_flag_mask |= flags; + neigh->n_flags |= flags; + neigh->n_mask |= NEIGH_ATTR_FLAGS; +} + +/** + * Get neighbour flags + * @arg neigh neighbour handle + * @return Neighbour flags + */ +unsigned int rtnl_neigh_get_flags(struct rtnl_neigh *neigh) +{ + return neigh->n_flags; +} + +/** + * Unset neighbour flags + * @arg neigh neighbour to change + * @arg flags flag to unset + */ +void rtnl_neigh_unset_flags(struct rtnl_neigh *neigh, unsigned int flags) +{ + neigh->n_flag_mask |= flags; + neigh->n_flags &= ~flags; + neigh->n_mask |= NEIGH_ATTR_FLAGS; +} + +/** + * Set the interface index of device this neighbour is on + * @arg neigh neighbour to change + * @arg ifindex new interface index + */ +void rtnl_neigh_set_ifindex(struct rtnl_neigh *neigh, int ifindex) +{ + neigh->n_ifindex = ifindex; + neigh->n_mask |= NEIGH_ATTR_IFINDEX; +} + +/** + * Get the interface index of the device this neighbour is on + * @arg neigh neighbour handle + * @return Interface index or RTNL_LINK_NOT_FOUND if not set + */ +int rtnl_neigh_get_ifindex(struct rtnl_neigh *neigh) +{ + if (neigh->n_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->n_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->n_mask |= NEIGH_ATTR_FAMILY; + } + } + + if (*pos) + nl_addr_put(*pos); + + nl_addr_get(new); + *pos = new; + + neigh->n_mask |= flag; + + return 0; +} + +/** + * Set link layer address of a neighbour + * @arg neigh neighbour to change + * @arg addr new link layer address + * + * Assigns the new link layer address to the specified neighbour handle. + * + * @note The prefix length of the address will be ignored. + */ +void rtnl_neigh_set_lladdr(struct rtnl_neigh *neigh, struct nl_addr *addr) +{ + __assign_addr(neigh, &neigh->n_lladdr, addr, NEIGH_ATTR_LLADDR, 1); +} + +/** + * Get link layer address of a neighbour + * @arg neigh neighbour handle + * @return Link layer address or NULL if not set + */ +struct nl_addr *rtnl_neigh_get_lladdr(struct rtnl_neigh *neigh) +{ + if (neigh->n_mask & NEIGH_ATTR_LLADDR) + return neigh->n_lladdr; + else + return NULL; +} + +/** + * Set destination address of a neighbour + * @arg neigh neighbour to change + * @arg addr new destination address + * + * Assigns the new destination address to the specified neighbour handle. + * The address is validated against the address family if set already via + * rtnl_neigh_set_family(). The assignment fails if the address families + * mismatch. In case the address family has not been specified yet, the + * address family of this new address is elected to be the requirement. + * + * @return 0 on success or a negative error code. + */ +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); +} + +/** + * Get the destination address of a neighbour + * @arg neigh neighbour handle + * @return Destination address or NULL if not set + */ +struct nl_addr *rtnl_neigh_get_dst(struct rtnl_neigh *neigh) +{ + if (neigh->n_mask & NEIGH_ATTR_DST) + return neigh->n_dst; + else + return NULL; +} + +/** + * Set destination address family + * @arg neigh neighbour to change + * @arg family new destination address family + */ +void rtnl_neigh_set_family(struct rtnl_neigh *neigh, int family) +{ + neigh->n_family = family; + neigh->n_mask |= NEIGH_ATTR_FAMILY; +} + +/** + * Set RTN type of a neighbour + * @arg neigh neighbour to change + * @arg type new rtn type + */ +void rtnl_neigh_set_type(struct rtnl_neigh *neigh, int type) +{ + neigh->n_type = type; + neigh->n_mask = NEIGH_ATTR_TYPE; +} + +/** + * Get RTN type of a neighbour + * @arg neigh neighbour handle + * @return Type or -1 if not set + */ +int rtnl_neigh_get_type(struct rtnl_neigh *neigh) +{ + if (neigh->n_mask & NEIGH_ATTR_TYPE) + return neigh->n_type; + else + return -1; +} + +/** @} */ + +static struct nl_cache_ops rtnl_neigh_ops = { + .co_name = "route/neigh", + .co_size = sizeof(struct rtnl_neigh), + .co_hdrsize = sizeof(struct ndmsg), + .co_msgtypes = { + { RTM_NEWNEIGH, "new" }, + { RTM_DELNEIGH, "delete" }, + { RTM_GETNEIGH, "get" }, + { -1, NULL }, + }, + .co_protocol = NETLINK_ROUTE, + .co_request_update = neigh_request_update, + .co_msg_parser = neigh_msg_parser, + .co_free_data = neigh_free_data, + .co_dump[NL_DUMP_BRIEF] = neigh_dump_brief, + .co_dump[NL_DUMP_FULL] = neigh_dump_full, + .co_dump[NL_DUMP_STATS] = neigh_dump_stats, + .co_dump[NL_DUMP_XML] = neigh_dump_xml, + .co_dump[NL_DUMP_ENV] = neigh_dump_env, + .co_filter = neigh_filter, +}; + +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); +} + +/** @} */