diff options
Diffstat (limited to 'proto/mrt/mrt.c')
| -rw-r--r-- | proto/mrt/mrt.c | 882 |
1 files changed, 882 insertions, 0 deletions
diff --git a/proto/mrt/mrt.c b/proto/mrt/mrt.c new file mode 100644 index 00000000..5c457b6c --- /dev/null +++ b/proto/mrt/mrt.c @@ -0,0 +1,882 @@ +/* + * BIRD -- Multi-Threaded Routing Toolkit (MRT) Protocol + * + * (c) 2017--2018 Ondrej Zajicek <santiago@crfreenet.org> + * (c) 2017--2018 CZ.NIC z.s.p.o. + * + * Can be freely distributed and used under the terms of the GNU GPL. + */ + +/** + * DOC: Multi-Threaded Routing Toolkit (MRT) protocol + * + * The MRT protocol is implemented in just one file: |mrt.c|. It contains of + * several parts: Generic functions for preparing MRT messages in a buffer, + * functions for MRT table dump (called from timer or CLI), functions for MRT + * BGP4MP dump (called from BGP), and the usual protocol glue. For the MRT table + * dump, the key structure is struct mrt_table_dump_state, which contains all + * necessary data and created when the MRT dump cycle is started for the + * duration of the MRT dump. The MBGP4MP dump is currently not bound to MRT + * protocol instance and uses the config->mrtdump_file fd. + * + * The protocol is simple, just periodically scans routing table and export it + * to a file. It does not use the regular update mechanism, but a direct access + * in order to handle iteration through multiple routing tables. The table dump + * needs to dump all peers first and then use indexes to address the peers, we + * use a hash table (@peer_hash) to find peer index based on BGP protocol key + * attributes. + * + * One thing worth documenting is the locking. During processing, the currently + * processed table (@table field in the state structure) is locked and also the + * explicitly named table is locked (@table_ptr field in the state structure) if + * specified. Between dumps no table is locked. Also the current config is + * locked (by config_add_obstacle()) during table dumps as some data (strings, + * filters) are shared from the config and the running table dump may be + * interrupted by reconfiguration. + * + * Supported standards: + * - RFC 6396 - MRT format standard + * - RFC 8050 - ADD_PATH extension + */ + +#include <unistd.h> +#include <limits.h> +#include <errno.h> + +#include "mrt.h" + +#include "nest/cli.h" +#include "filter/filter.h" +#include "proto/bgp/bgp.h" +#include "sysdep/unix/unix.h" + + +#ifdef PATH_MAX +#define BIRD_PATH_MAX PATH_MAX +#else +#define BIRD_PATH_MAX 4096 +#endif + +#define mrt_log(s, msg, args...) \ + ({ \ + if (s->cli) \ + cli_printf(s->cli, -8009, msg, ## args); \ + if (s->proto) \ + log(L_ERR "%s: " msg, s->proto->p.name, ## args); \ + }) + + +/* + * MRT buffer code + */ + +static void +mrt_buffer_init(buffer *b, pool *pool, size_t n) +{ + b->start = mb_alloc(pool, n); + b->pos = b->start; + b->end = b->start + n; +} + +static void +mrt_buffer_grow(buffer *b, size_t n) +{ + size_t used = b->pos - b->start; + size_t size = b->end - b->start; + size_t req = used + n; + + while (size < req) + size = size * 3 / 2; + + b->start = mb_realloc(b->start, size); + b->pos = b->start + used; + b->end = b->start + size; +} + +static inline void +mrt_buffer_need(buffer *b, size_t n) +{ + if (b->pos + n > b->end) + mrt_buffer_grow(b, n); +} + +static inline uint +mrt_buffer_pos(buffer *b) +{ + return b->pos - b->start; +} + +static inline void +mrt_buffer_flush(buffer *b) +{ + b->pos = b->start; +} + +#define MRT_DEFINE_TYPE(S, T) \ + static inline void mrt_put_##S##_(buffer *b, T x) \ + { \ + put_##S(b->pos, x); \ + b->pos += sizeof(T); \ + } \ + \ + static inline void mrt_put_##S(buffer *b, T x) \ + { \ + mrt_buffer_need(b, sizeof(T)); \ + put_##S(b->pos, x); \ + b->pos += sizeof(T); \ + } + +MRT_DEFINE_TYPE(u8, u8) +MRT_DEFINE_TYPE(u16, u16) +MRT_DEFINE_TYPE(u32, u32) +MRT_DEFINE_TYPE(u64, u64) +MRT_DEFINE_TYPE(ip4, ip4_addr) +MRT_DEFINE_TYPE(ip6, ip6_addr) + +static inline void +mrt_put_ipa(buffer *b, ip_addr x) +{ + if (ipa_is_ip4(x)) + mrt_put_ip4(b, ipa_to_ip4(x)); + else + mrt_put_ip6(b, ipa_to_ip6(x)); +} + +static inline void +mrt_put_data(buffer *b, const void *src, size_t n) +{ + if (!n) + return; + + mrt_buffer_need(b, n); + memcpy(b->pos, src, n); + b->pos += n; +} + +static void +mrt_init_message(buffer *b, u16 type, u16 subtype) +{ + /* Reset buffer */ + mrt_buffer_flush(b); + mrt_buffer_need(b, MRT_HDR_LENGTH); + + /* Prepare header */ + mrt_put_u32_(b, now_real); + mrt_put_u16_(b, type); + mrt_put_u16_(b, subtype); + + /* Message length, will be fixed later */ + mrt_put_u32_(b, 0); +} + +static void +mrt_dump_message(buffer *b, int fd) +{ + uint len = mrt_buffer_pos(b); + + /* Fix message length */ + ASSERT(len >= MRT_HDR_LENGTH); + put_u32(b->start + 8, len - MRT_HDR_LENGTH); + + if (fd < 0) + return; + + if (write(fd, b->start, len) < 0) + log(L_ERR "Write to MRT file failed: %m"); /* TODO: name of file */ +} + +static int +bstrsub(char *dst, size_t n, const char *src, const char *key, const char *val) +{ + const char *last, *next; + char *pos = dst; + size_t step, klen = strlen(key), vlen = strlen(val); + + for (last = src; next = strstr(last, key); last = next + klen) + { + step = next - last; + if (n <= step + vlen) + return 0; + + memcpy(pos, last, step); + ADVANCE(pos, n, step); + + memcpy(pos, val, vlen); + ADVANCE(pos, n, vlen); + } + + step = strlen(last); + if (n <= step) + return 0; + + memcpy(pos, last, step); + ADVANCE(pos, n, step); + + pos[0] = 0; + return 1; +} + +static inline rtable * +mrt_next_table_(rtable *tab, rtable *tab_ptr, const char *pattern) +{ + /* Handle explicit table, return it in the first pass */ + if (tab_ptr) + return !tab ? tab_ptr : NULL; + + /* Walk routing_tables list, starting after tab (if non-NULL) */ + for (tab = !tab ? HEAD(routing_tables) : NODE_NEXT(tab); + NODE_VALID(tab); + tab = NODE_NEXT(tab)) + if (patmatch(pattern, tab->name)) + return tab; + + return NULL; +} + +static rtable * +mrt_next_table(struct mrt_table_dump_state *s) +{ + rtable *tab = mrt_next_table_(s->table, s->table_ptr, s->table_expr); + + if (s->table) + rt_unlock_table(s->table); + + s->table = tab; + + if (s->table) + rt_lock_table(s->table); + + return s->table; +} + +static int +mrt_open_file(struct mrt_table_dump_state *s) +{ + char fmt1[BIRD_PATH_MAX]; + char name[BIRD_PATH_MAX]; + + if (!bstrsub(fmt1, sizeof(fmt1), s->filename, "%N", s->table->name) || + !tm_format_real_time(name, sizeof(name), fmt1, now_real)) + { + mrt_log(s, "Invalid filename '%s'", s->filename); + return 0; + } + + s->file = rf_open(s->pool, name, "a"); + if (!s->file) + { + mrt_log(s, "Unable to open MRT file '%s': %m", name); + return 0; + } + + s->fd = rf_fileno(s->file); + s->time_offset = now_real - now; + + return 1; +} + +static void +mrt_close_file(struct mrt_table_dump_state *s) +{ + rfree(s->file); + s->file = NULL; + s->fd = -1; +} + + +/* + * MRT Table Dump: Peer Index Table + */ + +#define PEER_KEY(n) n->peer_id, n->peer_as, n->peer_ip +#define PEER_NEXT(n) n->next +#define PEER_EQ(id1,as1,ip1,id2,as2,ip2) \ + id1 == id2 && as1 == as2 && ipa_equal(ip1, ip2) +#define PEER_FN(id,as,ip) ipa_hash(ip) + +static void +mrt_peer_table_header(struct mrt_table_dump_state *s, u32 router_id, const char *name) +{ + buffer *b = &s->buf; + + /* Collector BGP ID */ + mrt_put_u32(b, router_id); + + /* View Name */ + uint name_length = name ? strlen(name) : 0; + name_length = MIN(name_length, 65535); + mrt_put_u16(b, name_length); + mrt_put_data(b, name, name_length); + + /* Peer Count, will be fixed later */ + s->peer_count = 0; + s->peer_count_offset = mrt_buffer_pos(b); + mrt_put_u16(b, 0); + + HASH_INIT(s->peer_hash, s->pool, 10); +} + +static void +mrt_peer_table_entry(struct mrt_table_dump_state *s, u32 peer_id, u32 peer_as, ip_addr peer_ip) +{ + buffer *b = &s->buf; + + uint type = MRT_PEER_TYPE_32BIT_ASN; + if (ipa_is_ip6(peer_ip)) + type |= MRT_PEER_TYPE_IPV6; + + /* Dump peer to buffer */ + mrt_put_u8(b, type); + mrt_put_u32(b, peer_id); + mrt_put_ipa(b, peer_ip); + mrt_put_u32(b, peer_as); + + /* Add peer to hash table */ + struct mrt_peer_entry *n = lp_allocz(s->peer_lp, sizeof(struct mrt_peer_entry)); + n->peer_id = peer_id; + n->peer_as = peer_as; + n->peer_ip = peer_ip; + n->index = s->peer_count++; + + HASH_INSERT(s->peer_hash, PEER, n); +} + +static void +mrt_peer_table_dump(struct mrt_table_dump_state *s) +{ + mrt_init_message(&s->buf, MRT_TABLE_DUMP_V2, MRT_PEER_INDEX_TABLE); + mrt_peer_table_header(s, config->router_id, s->table->name); + + /* 0 is fake peer for non-BGP routes */ + mrt_peer_table_entry(s, 0, 0, IPA_NONE); + +#ifdef CONFIG_BGP + struct proto *P; + WALK_LIST(P, active_proto_list) + if (P->proto == &proto_bgp) + { + struct bgp_proto *p = (void *) P; + mrt_peer_table_entry(s, p->remote_id, p->remote_as, p->cf->remote_ip); + } +#endif + + /* Fix Peer Count */ + put_u16(s->buf.start + s->peer_count_offset, s->peer_count); + + mrt_dump_message(&s->buf, s->fd); +} + +static void +mrt_peer_table_flush(struct mrt_table_dump_state *s) +{ + lp_flush(s->peer_lp); + HASH_FREE(s->peer_hash); +} + + +/* + * MRT Table Dump: RIB Table + */ + +static void +mrt_rib_table_header(struct mrt_table_dump_state *s, net *n) +{ + buffer *b = &s->buf; + + /* Sequence Number */ + mrt_put_u32(b, s->seqnum); + + /* Network Prefix */ + ip_addr a = n->n.prefix; + ipa_hton(a); + + mrt_put_u8(b, n->n.pxlen); + mrt_put_data(b, &a, BYTES(n->n.pxlen)); + + /* Entry Count, will be fixed later */ + s->entry_count = 0; + s->entry_count_offset = mrt_buffer_pos(b); + mrt_put_u16(b, 0); +} + +static void +mrt_rib_table_entry(struct mrt_table_dump_state *s, rte *r, struct ea_list *tmpa) +{ + buffer *b = &s->buf; + uint peer = 0; + +#ifdef CONFIG_BGP + /* Find peer index */ + if (r->attrs->src->proto->proto == &proto_bgp) + { + struct bgp_proto *p = (void *) r->attrs->src->proto; + struct mrt_peer_entry *n = + HASH_FIND(s->peer_hash, PEER, p->remote_id, p->remote_as, p->cf->remote_ip); + + peer = n ? n->index : 0; + } +#endif + + /* Peer Index and Originated Time */ + mrt_put_u16(b, peer); + mrt_put_u32(b, r->lastmod + s->time_offset); + + /* Path Identifier */ + if (s->add_path) + mrt_put_u32(b, r->attrs->src->private_id); + + /* Route Attributes */ + mrt_put_u16(b, 0); + +#ifdef CONFIG_BGP + if (r->attrs->eattrs || tmpa) + { + struct ea_list *eattrs = r->attrs->eattrs; + + if (!rta_is_cached(r->attrs) || tmpa) + { + /* Attributes must be merged and sorted for bgp_encode_attrs() */ + tmpa = ea_append(tmpa, eattrs); + eattrs = alloca(ea_scan(tmpa)); + ea_merge(tmpa, eattrs); + ea_sort(eattrs); + } + + mrt_buffer_need(b, MRT_ATTR_BUFFER_SIZE); + int alen = bgp_encode_attrs(NULL, b->pos, eattrs, MRT_ATTR_BUFFER_SIZE); + + if (alen < 0) + { + mrt_log(s, "Attribute list too long for %I/%d", + r->net->n.prefix, r->net->n.pxlen); + alen = 0; + } + + put_u16(b->pos - 2, alen); + b->pos += alen; + } +#endif + + s->entry_count++; +} + +static void +mrt_rib_table_dump(struct mrt_table_dump_state *s, net *n, int add_path) +{ + rte *rt, *rt0; + int subtype; + + s->add_path = add_path; + +#ifndef IPV6 + subtype = !add_path ? MRT_RIB_IPV4_UNICAST : MRT_RIB_IPV4_UNICAST_ADDPATH; +#else + subtype = !add_path ? MRT_RIB_IPV6_UNICAST : MRT_RIB_IPV6_UNICAST_ADDPATH; +#endif + + mrt_init_message(&s->buf, MRT_TABLE_DUMP_V2, subtype); + mrt_rib_table_header(s, n); + + for (rt0 = n->routes; rt = rt0; rt0 = rt0->next) + { + if (rte_is_filtered(rt)) + continue; + + /* Skip routes that should be reported in the other phase */ + if (!s->always_add_path && (!rt->attrs->src->private_id != !s->add_path)) + { + s->want_add_path = 1; + continue; + } + + struct ea_list *tmp_attrs = rte_make_tmp_attrs(rt, s->linpool); + + if (f_run(s->filter, &rt, &tmp_attrs, s->linpool, 0) <= F_ACCEPT) + mrt_rib_table_entry(s, rt, tmp_attrs); + + if (rt != rt0) + rte_free(rt); + + lp_flush(s->linpool); + } + + /* Fix Entry Count */ + put_u16(s->buf.start + s->entry_count_offset, s->entry_count); + + /* Update max counter */ + s->max -= 1 + s->entry_count; + + /* Skip empty entries */ + if (!s->entry_count) + return; + + s->seqnum++; + mrt_dump_message(&s->buf, s->fd); +} + + +/* + * MRT Table Dump: main logic + */ + +static struct mrt_table_dump_state * +mrt_table_dump_init(pool *pp) +{ + pool *pool = rp_new(pp, "MRT Table Dump"); + struct mrt_table_dump_state *s = mb_allocz(pool, sizeof(struct mrt_table_dump_state)); + + s->pool = pool; + s->linpool = lp_new(pool, 4080); + s->peer_lp = lp_new(pool, 4080); + mrt_buffer_init(&s->buf, pool, 2 * MRT_ATTR_BUFFER_SIZE); + + /* We lock the current config as we may reference it indirectly by filter */ + s->config = config; + config_add_obstacle(s->config); + + s->fd = -1; + + return s; +} + +static void +mrt_table_dump_free(struct mrt_table_dump_state *s) +{ + if (s->table_open) + FIB_ITERATE_UNLINK(&s->fit, &s->table->fib); + + if (s->table) + rt_unlock_table(s->table); + + if (s->table_ptr) + rt_unlock_table(s->table_ptr); + + config_del_obstacle(s->config); + + rfree(s->pool); +} + + +static int +mrt_table_dump_step(struct mrt_table_dump_state *s) +{ + s->max = 2048; + + if (s->table_open) + goto step; + + while (mrt_next_table(s)) + { + if (!mrt_open_file(s)) + continue; + + mrt_peer_table_dump(s); + + FIB_ITERATE_INIT(&s->fit, &s->table->fib); + s->table_open = 1; + + step: + FIB_ITERATE_START(&s->table->fib, &s->fit, fn) + { + if (s->max < 0) + { + FIB_ITERATE_PUT(&s->fit, fn); + return 0; + } + + /* With Always ADD_PATH option, we jump directly to second phase */ + s->want_add_path = s->always_add_path; + + if (s->want_add_path == 0) + mrt_rib_table_dump(s, (net *) fn, 0); + + if (s->want_add_path == 1) + mrt_rib_table_dump(s, (net *) fn, 1); + } + FIB_ITERATE_END(fn); + s->table_open = 0; + + mrt_close_file(s); + mrt_peer_table_flush(s); + } + + return 1; +} + +static void +mrt_timer(timer *t) +{ + struct mrt_proto *p = t->data; + struct mrt_config *cf = (void *) (p->p.cf); + + if (p->table_dump) + { + log(L_WARN "%s: Earlier RIB table dump still not finished, skipping next one", p->p.name); + return; + } + + TRACE(D_EVENTS, "RIB table dump started"); + + struct mrt_table_dump_state *s = mrt_table_dump_init(p->p.pool); + + s->proto = p; + s->table_expr = cf->table_expr; + s->table_ptr = cf->table_cf ? cf->table_cf->table : NULL; + s->filter = cf->filter; + s->filename = cf->filename; + s->always_add_path = cf->always_add_path; + + if (s->table_ptr) + rt_lock_table(s->table_ptr); + + p->table_dump = s; + ev_schedule(p->event); +} + +static void +mrt_event(void *P) +{ + struct mrt_proto *p = P; + + if (!p->table_dump) + return; + + if (!mrt_table_dump_step(p->table_dump)) + { + ev_schedule(p->event); + return; + } + + mrt_table_dump_free(p->table_dump); + p->table_dump = NULL; + + TRACE(D_EVENTS, "RIB table dump done"); + + if (p->p.proto_state == PS_STOP) + proto_notify_state(&p->p, PS_DOWN); +} + + +/* + * MRT Table Dump: CLI command + */ + +static void +mrt_dump_cont(struct cli *c) +{ + if (!mrt_table_dump_step(c->rover)) + return; + + cli_printf(c, 0, ""); + c->cont = c->cleanup = NULL; +} + +static void +mrt_dump_cleanup(struct cli *c) +{ + mrt_table_dump_free(c->rover); + c->rover = NULL; +} + +void +mrt_dump_cmd(struct mrt_dump_data *d) +{ + if (cli_access_restricted()) + return; + + if (!d->table_expr && !d->table_ptr) + cf_error("Table not specified"); + + if (!d->filename) + cf_error("File not specified"); + + struct mrt_table_dump_state *s = mrt_table_dump_init(this_cli->pool); + + s->cli = this_cli; + s->table_expr = d->table_expr; + s->table_ptr = d->table_ptr; + s->filter = d->filter; + s->filename = d->filename; + + if (s->table_ptr) + rt_lock_table(s->table_ptr); + + this_cli->cont = mrt_dump_cont; + this_cli->cleanup = mrt_dump_cleanup; + this_cli->rover = s; +} + + +/* + * MRT BGP4MP dump + */ + +static buffer * +mrt_bgp_buffer(void) +{ + /* Static buffer for BGP4MP dump, TODO: change to use MRT protocol */ + static buffer b; + + if (!b.start) + mrt_buffer_init(&b, &root_pool, 1024); + + return &b; +} + +static void +mrt_bgp_header(buffer *b, struct mrt_bgp_data *d) +{ + if (d->as4) + { + mrt_put_u32(b, d->peer_as); + mrt_put_u32(b, d->local_as); + } + else + { + mrt_put_u16(b, (d->peer_as <= 0xFFFF) ? d->peer_as : AS_TRANS); + mrt_put_u16(b, (d->local_as <= 0xFFFF) ? d->local_as : AS_TRANS); + } + + mrt_put_u16(b, (d->index <= 0xFFFF) ? d->index : 0); + mrt_put_u16(b, d->af); + + if (d->af == BGP_AF_IPV4) + { + mrt_put_ip4(b, ipa_to_ip4(d->peer_ip)); + mrt_put_ip4(b, ipa_to_ip4(d->local_ip)); + } + else + { + mrt_put_ip6(b, ipa_to_ip6(d->peer_ip)); + mrt_put_ip6(b, ipa_to_ip6(d->local_ip)); + } +} + +void +mrt_dump_bgp_message(struct mrt_bgp_data *d) +{ + const u16 subtypes[] = { + MRT_BGP4MP_MESSAGE, MRT_BGP4MP_MESSAGE_AS4, + MRT_BGP4MP_MESSAGE_LOCAL, MRT_BGP4MP_MESSAGE_AS4_LOCAL, + MRT_BGP4MP_MESSAGE_ADDPATH, MRT_BGP4MP_MESSAGE_AS4_ADDPATH, + MRT_BGP4MP_MESSAGE_LOCAL_ADDPATH, MRT_BGP4MP_MESSAGE_AS4_LOCAL_ADDPATH, + }; + + buffer *b = mrt_bgp_buffer(); + mrt_init_message(b, MRT_BGP4MP, subtypes[d->as4 + 4*d->add_path]); + mrt_bgp_header(b, d); + mrt_put_data(b, d->message, d->msg_len); + mrt_dump_message(b, config->mrtdump_file); +} + +void +mrt_dump_bgp_state_change(struct mrt_bgp_data *d) +{ + /* Convert state from our BS_* values to values used in MRTDump */ + const u16 states[BS_MAX] = {1, 2, 3, 4, 5, 6, 1}; + + if (states[d->old_state] == states[d->new_state]) + return; + + /* Always use AS4 mode for STATE_CHANGE */ + d->as4 = 1; + + buffer *b = mrt_bgp_buffer(); + mrt_init_message(b, MRT_BGP4MP, MRT_BGP4MP_STATE_CHANGE_AS4); + mrt_bgp_header(b, d); + mrt_put_u16(b, states[d->old_state]); + mrt_put_u16(b, states[d->new_state]); + mrt_dump_message(b, config->mrtdump_file); +} + + +/* + * MRT protocol glue + */ + +void +mrt_check_config(struct proto_config *C) +{ + struct mrt_config *cf = (void *) C; + + /* c.table must be always defined, but it is relevant only if table_expr is not set */ + if (!cf->table_expr) + cf->table_cf = cf->c.table; + + if (!cf->table_expr && !cf->table_cf) + cf_error("Table not specified"); + + if (!cf->filename) + cf_error("File not specified"); + + if (!cf->period) + cf_error("Period not specified"); +} + +static struct proto * +mrt_init(struct proto_config *C) +{ + struct proto *P = proto_new(C, sizeof(struct mrt_proto)); + + return P; +} + +static int +mrt_start(struct proto *P) +{ + struct mrt_proto *p = (void *) P; + struct mrt_config *cf = (void *) (P->cf); + + p->timer = tm_new_set(P->pool, mrt_timer, p, 0, cf->period); + p->event = ev_new_set(P->pool, mrt_event, p); + + tm_start(p->timer, cf->period); + + return PS_UP; +} + +static int +mrt_shutdown(struct proto *P) +{ + struct mrt_proto *p = (void *) P; + + return p->table_dump ? PS_STOP : PS_DOWN; +} + +static int +mrt_reconfigure(struct proto *P, struct proto_config *CF) +{ + struct mrt_proto *p = (void *) P; + struct mrt_config *old = (void *) (P->cf); + struct mrt_config *new = (void *) CF; + + if (new->period != old->period) + { + TRACE(D_EVENTS, "Changing period from %d to %d s", old->period, new->period); + + bird_clock_t new_time = p->timer->expires - old->period + new->period; + tm_start(p->timer, (new_time > now) ? (new_time - now) : 0); + p->timer->recurrent = new->period; + } + + return 1; +} + +static void +mrt_copy_config(struct proto_config *dest, struct proto_config *src) +{ + /* Just a shallow copy, not many items here */ + proto_copy_rest(dest, src, sizeof(struct mrt_config)); +} + + +struct protocol proto_mrt = { + .name = "MRT", + .template = "mrt%d", + .config_size = sizeof(struct mrt_config), + .init = mrt_init, + .start = mrt_start, + .shutdown = mrt_shutdown, + .reconfigure = mrt_reconfigure, + .copy_config = mrt_copy_config, +}; |