diff options
Diffstat (limited to 'babeld/message.c')
| -rw-r--r-- | babeld/message.c | 1561 |
1 files changed, 0 insertions, 1561 deletions
diff --git a/babeld/message.c b/babeld/message.c deleted file mode 100644 index 9dcfc6771c..0000000000 --- a/babeld/message.c +++ /dev/null @@ -1,1561 +0,0 @@ -/* - * This file is free software: you may copy, redistribute and/or modify it - * under the terms of the GNU General Public License as published by the - * Free Software Foundation, either version 2 of the License, or (at your - * option) any later version. - * - * This file is distributed in the hope that it will be useful, but - * WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU - * General Public License for more details. - * - * You should have received a copy of the GNU General Public License - * along with this program. If not, see <http://www.gnu.org/licenses/>. - * - * This file incorporates work covered by the following copyright and - * permission notice: - * - -Copyright (c) 2007, 2008 by Juliusz Chroboczek - -Permission is hereby granted, free of charge, to any person obtaining a copy -of this software and associated documentation files (the "Software"), to deal -in the Software without restriction, including without limitation the rights -to use, copy, modify, merge, publish, distribute, sublicense, and/or sell -copies of the Software, and to permit persons to whom the Software is -furnished to do so, subject to the following conditions: - -The above copyright notice and this permission notice shall be included in -all copies or substantial portions of the Software. - -THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR -IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, -FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE -AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER -LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, -OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN -THE SOFTWARE. -*/ - -#include <zebra.h> -#include "if.h" - -#include "babeld.h" -#include "util.h" -#include "net.h" -#include "babel_interface.h" -#include "source.h" -#include "neighbour.h" -#include "route.h" -#include "xroute.h" -#include "resend.h" -#include "message.h" -#include "kernel.h" - -unsigned char packet_header[4] = {42, 2}; - -int split_horizon = 1; - -unsigned short myseqno = 0; -struct timeval seqno_time = {0, 0}; - -#define UNICAST_BUFSIZE 1024 -int unicast_buffered = 0; -unsigned char *unicast_buffer = NULL; -struct neighbour *unicast_neighbour = NULL; -struct timeval unicast_flush_timeout = {0, 0}; - -static const unsigned char v4prefix[16] = - {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0xFF, 0xFF, 0, 0, 0, 0 }; - -/* Parse a network prefix, encoded in the somewhat baroque compressed - representation used by Babel. Return the number of bytes parsed. */ -static int -network_prefix(int ae, int plen, unsigned int omitted, - const unsigned char *p, const unsigned char *dp, - unsigned int len, unsigned char *p_r) -{ - unsigned pb; - unsigned char prefix[16]; - int ret = -1; - - if(plen >= 0) - pb = (plen + 7) / 8; - else if(ae == 1) - pb = 4; - else - pb = 16; - - if(pb > 16) - return -1; - - memset(prefix, 0, 16); - - switch(ae) { - case 0: - ret = 0; - break; - case 1: - if(omitted > 4 || pb > 4 || (pb > omitted && len < pb - omitted)) - return -1; - memcpy(prefix, v4prefix, 12); - if(omitted) { - if (dp == NULL || !v4mapped(dp)) return -1; - memcpy(prefix, dp, 12 + omitted); - } - if(pb > omitted) memcpy(prefix + 12 + omitted, p, pb - omitted); - ret = pb - omitted; - break; - case 2: - if(omitted > 16 || (pb > omitted && len < pb - omitted)) return -1; - if(omitted) { - if (dp == NULL || v4mapped(dp)) return -1; - memcpy(prefix, dp, omitted); - } - if(pb > omitted) memcpy(prefix + omitted, p, pb - omitted); - ret = pb - omitted; - break; - case 3: - if(pb > 8 && len < pb - 8) return -1; - prefix[0] = 0xfe; - prefix[1] = 0x80; - if(pb > 8) memcpy(prefix + 8, p, pb - 8); - ret = pb - 8; - break; - default: - return -1; - } - - mask_prefix(p_r, prefix, plen < 0 ? 128 : ae == 1 ? plen + 96 : plen); - return ret; -} - -static void -parse_route_attributes(const unsigned char *a, int alen, - unsigned char *channels) -{ - int type, len, i = 0; - - while(i < alen) { - type = a[i]; - if(type == 0) { - i++; - continue; - } - - if(i + 1 > alen) { - fprintf(stderr, "Received truncated attributes.\n"); - return; - } - len = a[i + 1]; - if(i + len > alen) { - fprintf(stderr, "Received truncated attributes.\n"); - return; - } - - if(type == 1) { - /* Nothing. */ - } else if(type == 2) { - if(len > DIVERSITY_HOPS) { - fprintf(stderr, - "Received overlong channel information (%d > %d).\n", - len, DIVERSITY_HOPS); - len = DIVERSITY_HOPS; - } - if(memchr(a + i + 2, 0, len) != NULL) { - /* 0 is reserved. */ - fprintf(stderr, "Channel information contains 0!"); - return; - } - memset(channels, 0, DIVERSITY_HOPS); - memcpy(channels, a + i + 2, len); - } else { - fprintf(stderr, "Received unknown route attribute %d.\n", type); - } - - i += len + 2; - } -} - -static int -network_address(int ae, const unsigned char *a, unsigned int len, - unsigned char *a_r) -{ - return network_prefix(ae, -1, 0, a, NULL, len, a_r); -} - -static int -channels_len(unsigned char *channels) -{ - unsigned char *p = memchr(channels, 0, DIVERSITY_HOPS); - return p ? (p - channels) : DIVERSITY_HOPS; -} - -void -parse_packet(const unsigned char *from, struct interface *ifp, - const unsigned char *packet, int packetlen) -{ - int i; - const unsigned char *message; - unsigned char type, len; - int bodylen; - struct neighbour *neigh; - int have_router_id = 0, have_v4_prefix = 0, have_v6_prefix = 0, - have_v4_nh = 0, have_v6_nh = 0; - unsigned char router_id[8], v4_prefix[16], v6_prefix[16], - v4_nh[16], v6_nh[16]; - - if(!linklocal(from)) { - zlog_err("Received packet from non-local address %s.", - format_address(from)); - return; - } - - if(packet[0] != 42) { - zlog_err("Received malformed packet on %s from %s.", - ifp->name, format_address(from)); - return; - } - - if(packet[1] != 2) { - zlog_err("Received packet with unknown version %d on %s from %s.", - packet[1], ifp->name, format_address(from)); - return; - } - - neigh = find_neighbour(from, ifp); - if(neigh == NULL) { - zlog_err("Couldn't allocate neighbour."); - return; - } - - DO_NTOHS(bodylen, packet + 2); - - if(bodylen + 4 > packetlen) { - zlog_err("Received truncated packet (%d + 4 > %d).", - bodylen, packetlen); - bodylen = packetlen - 4; - } - - i = 0; - while(i < bodylen) { - message = packet + 4 + i; - type = message[0]; - if(type == MESSAGE_PAD1) { - debugf(BABEL_DEBUG_COMMON,"Received pad1 from %s on %s.", - format_address(from), ifp->name); - i++; - continue; - } - if(i + 1 > bodylen) { - zlog_err("Received truncated message."); - break; - } - len = message[1]; - if(i + len > bodylen) { - zlog_err("Received truncated message."); - break; - } - - if(type == MESSAGE_PADN) { - debugf(BABEL_DEBUG_COMMON,"Received pad%d from %s on %s.", - len, format_address(from), ifp->name); - } else if(type == MESSAGE_ACK_REQ) { - unsigned short nonce, interval; - if(len < 6) goto fail; - DO_NTOHS(nonce, message + 4); - DO_NTOHS(interval, message + 6); - debugf(BABEL_DEBUG_COMMON,"Received ack-req (%04X %d) from %s on %s.", - nonce, interval, format_address(from), ifp->name); - send_ack(neigh, nonce, interval); - } else if(type == MESSAGE_ACK) { - debugf(BABEL_DEBUG_COMMON,"Received ack from %s on %s.", - format_address(from), ifp->name); - /* Nothing right now */ - } else if(type == MESSAGE_HELLO) { - unsigned short seqno, interval; - int changed; - if(len < 6) goto fail; - DO_NTOHS(seqno, message + 4); - DO_NTOHS(interval, message + 6); - debugf(BABEL_DEBUG_COMMON,"Received hello %d (%d) from %s on %s.", - seqno, interval, - format_address(from), ifp->name); - changed = update_neighbour(neigh, seqno, interval); - update_neighbour_metric(neigh, changed); - if(interval > 0) - schedule_neighbours_check(interval * 10, 0); - } else if(type == MESSAGE_IHU) { - unsigned short txcost, interval; - unsigned char address[16]; - int rc; - if(len < 6) goto fail; - DO_NTOHS(txcost, message + 4); - DO_NTOHS(interval, message + 6); - rc = network_address(message[2], message + 8, len - 6, address); - if(rc < 0) goto fail; - debugf(BABEL_DEBUG_COMMON,"Received ihu %d (%d) from %s on %s for %s.", - txcost, interval, - format_address(from), ifp->name, - format_address(address)); - if(message[2] == 0 || is_interface_ll_address(ifp, address)) { - int changed = txcost != neigh->txcost; - neigh->txcost = txcost; - neigh->ihu_time = babel_now; - neigh->ihu_interval = interval; - update_neighbour_metric(neigh, changed); - if(interval > 0) - schedule_neighbours_check(interval * 10 * 3, 0); - } - } else if(type == MESSAGE_ROUTER_ID) { - if(len < 10) { - have_router_id = 0; - goto fail; - } - memcpy(router_id, message + 4, 8); - have_router_id = 1; - debugf(BABEL_DEBUG_COMMON,"Received router-id %s from %s on %s.", - format_eui64(router_id), format_address(from), ifp->name); - } else if(type == MESSAGE_NH) { - unsigned char nh[16]; - int rc; - if(len < 2) { - have_v4_nh = 0; - have_v6_nh = 0; - goto fail; - } - rc = network_address(message[2], message + 4, len - 2, - nh); - if(rc < 0) { - have_v4_nh = 0; - have_v6_nh = 0; - goto fail; - } - debugf(BABEL_DEBUG_COMMON,"Received nh %s (%d) from %s on %s.", - format_address(nh), message[2], - format_address(from), ifp->name); - if(message[2] == 1) { - memcpy(v4_nh, nh, 16); - have_v4_nh = 1; - } else { - memcpy(v6_nh, nh, 16); - have_v6_nh = 1; - } - } else if(type == MESSAGE_UPDATE) { - unsigned char prefix[16], *nh; - unsigned char plen; - unsigned char channels[DIVERSITY_HOPS]; - unsigned short interval, seqno, metric; - int rc, parsed_len; - if(len < 10) { - if(len < 2 || message[3] & 0x80) - have_v4_prefix = have_v6_prefix = 0; - goto fail; - } - DO_NTOHS(interval, message + 6); - DO_NTOHS(seqno, message + 8); - DO_NTOHS(metric, message + 10); - if(message[5] == 0 || - (message[3] == 1 ? have_v4_prefix : have_v6_prefix)) - rc = network_prefix(message[2], message[4], message[5], - message + 12, - message[2] == 1 ? v4_prefix : v6_prefix, - len - 10, prefix); - else - rc = -1; - if(rc < 0) { - if(message[3] & 0x80) - have_v4_prefix = have_v6_prefix = 0; - goto fail; - } - parsed_len = 10 + rc; - - plen = message[4] + (message[2] == 1 ? 96 : 0); - - if(message[3] & 0x80) { - if(message[2] == 1) { - memcpy(v4_prefix, prefix, 16); - have_v4_prefix = 1; - } else { - memcpy(v6_prefix, prefix, 16); - have_v6_prefix = 1; - } - } - if(message[3] & 0x40) { - if(message[2] == 1) { - memset(router_id, 0, 4); - memcpy(router_id + 4, prefix + 12, 4); - } else { - memcpy(router_id, prefix + 8, 8); - } - have_router_id = 1; - } - if(!have_router_id && message[2] != 0) { - zlog_err("Received prefix with no router id."); - goto fail; - } - debugf(BABEL_DEBUG_COMMON,"Received update%s%s for %s from %s on %s.", - (message[3] & 0x80) ? "/prefix" : "", - (message[3] & 0x40) ? "/id" : "", - format_prefix(prefix, plen), - format_address(from), ifp->name); - - if(message[2] == 0) { - if(metric < 0xFFFF) { - zlog_err("Received wildcard update with finite metric."); - goto done; - } - retract_neighbour_routes(neigh); - goto done; - } else if(message[2] == 1) { - if(!have_v4_nh) - goto fail; - nh = v4_nh; - } else if(have_v6_nh) { - nh = v6_nh; - } else { - nh = neigh->address; - } - - if(message[2] == 1) { - if(!babel_get_if_nfo(ifp)->ipv4) - goto done; - } - - if((ifp->flags & BABEL_IF_FARAWAY)) { - channels[0] = 0; - } else { - /* This will be overwritten by parse_route_attributes below. */ - if(metric < 256) { - /* Assume non-interfering (wired) link. */ - channels[0] = 0; - } else { - /* Assume interfering. */ - channels[0] = BABEL_IF_CHANNEL_INTERFERING; - channels[1] = 0; - } - - if(parsed_len < len) - parse_route_attributes(message + 2 + parsed_len, - len - parsed_len, channels); - } - - update_route(router_id, prefix, plen, seqno, metric, interval, - neigh, nh, - channels, channels_len(channels)); - } else if(type == MESSAGE_REQUEST) { - unsigned char prefix[16], plen; - int rc; - if(len < 2) goto fail; - rc = network_prefix(message[2], message[3], 0, - message + 4, NULL, len - 2, prefix); - if(rc < 0) goto fail; - plen = message[3] + (message[2] == 1 ? 96 : 0); - debugf(BABEL_DEBUG_COMMON,"Received request for %s from %s on %s.", - message[2] == 0 ? "any" : format_prefix(prefix, plen), - format_address(from), ifp->name); - if(message[2] == 0) { - struct babel_interface *babel_ifp =babel_get_if_nfo(neigh->ifp); - /* If a neighbour is requesting a full route dump from us, - we might as well send it an IHU. */ - send_ihu(neigh, NULL); - /* Since nodes send wildcard requests on boot, booting - a large number of nodes at the same time may cause an - update storm. Ignore a wildcard request that happens - shortly after we sent a full update. */ - if(babel_ifp->last_update_time < - (time_t)(babel_now.tv_sec - - MAX(babel_ifp->hello_interval / 100, 1))) - send_update(neigh->ifp, 0, NULL, 0); - } else { - send_update(neigh->ifp, 0, prefix, plen); - } - } else if(type == MESSAGE_MH_REQUEST) { - unsigned char prefix[16], plen; - unsigned short seqno; - int rc; - if(len < 14) goto fail; - DO_NTOHS(seqno, message + 4); - rc = network_prefix(message[2], message[3], 0, - message + 16, NULL, len - 14, prefix); - if(rc < 0) goto fail; - plen = message[3] + (message[2] == 1 ? 96 : 0); - debugf(BABEL_DEBUG_COMMON,"Received request (%d) for %s from %s on %s (%s, %d).", - message[6], - format_prefix(prefix, plen), - format_address(from), ifp->name, - format_eui64(message + 8), seqno); - handle_request(neigh, prefix, plen, message[6], - seqno, message + 8); - } else { - debugf(BABEL_DEBUG_COMMON,"Received unknown packet type %d from %s on %s.", - type, format_address(from), ifp->name); - } - done: - i += len + 2; - continue; - - fail: - zlog_err("Couldn't parse packet (%d, %d) from %s on %s.", - message[0], message[1], format_address(from), ifp->name); - goto done; - } - return; -} - -/* Under normal circumstances, there are enough moderation mechanisms - elsewhere in the protocol to make sure that this last-ditch check - should never trigger. But I'm superstitious. */ - -static int -check_bucket(struct interface *ifp) -{ - babel_interface_nfo *babel_ifp = babel_get_if_nfo(ifp); - if(babel_ifp->bucket <= 0) { - int seconds = babel_now.tv_sec - babel_ifp->bucket_time; - if(seconds > 0) { - babel_ifp->bucket = MIN(BUCKET_TOKENS_MAX, - seconds * BUCKET_TOKENS_PER_SEC); - } - /* Reset bucket time unconditionally, in case clock is stepped. */ - babel_ifp->bucket_time = babel_now.tv_sec; - } - - if(babel_ifp->bucket > 0) { - babel_ifp->bucket--; - return 1; - } else { - return 0; - } -} - -void -flushbuf(struct interface *ifp) -{ - int rc; - struct sockaddr_in6 sin6; - babel_interface_nfo *babel_ifp = babel_get_if_nfo(ifp); - - assert(babel_ifp->buffered <= babel_ifp->bufsize); - - flushupdates(ifp); - - if(babel_ifp->buffered > 0) { - debugf(BABEL_DEBUG_COMMON," (flushing %d buffered bytes on %s)", - babel_ifp->buffered, ifp->name); - if(check_bucket(ifp)) { - memset(&sin6, 0, sizeof(sin6)); - sin6.sin6_family = AF_INET6; - memcpy(&sin6.sin6_addr, protocol_group, 16); - sin6.sin6_port = htons(protocol_port); - sin6.sin6_scope_id = ifp->ifindex; - DO_HTONS(packet_header + 2, babel_ifp->buffered); - rc = babel_send(protocol_socket, - packet_header, sizeof(packet_header), - babel_ifp->sendbuf, babel_ifp->buffered, - (struct sockaddr*)&sin6, sizeof(sin6)); - if(rc < 0) - zlog_err("send: %s", safe_strerror(errno)); - } else { - zlog_err("Warning: bucket full, dropping packet to %s.", - ifp->name); - } - } - VALGRIND_MAKE_MEM_UNDEFINED(babel_ifp->sendbuf, babel_ifp->bufsize); - babel_ifp->buffered = 0; - babel_ifp->have_buffered_hello = 0; - babel_ifp->have_buffered_id = 0; - babel_ifp->have_buffered_nh = 0; - babel_ifp->have_buffered_prefix = 0; - babel_ifp->flush_timeout.tv_sec = 0; - babel_ifp->flush_timeout.tv_usec = 0; -} - -static void -schedule_flush(struct interface *ifp) -{ - babel_interface_nfo *babel_ifp = babel_get_if_nfo(ifp); - unsigned msecs = jitter(babel_ifp, 0); - if(babel_ifp->flush_timeout.tv_sec != 0 && - timeval_minus_msec(&babel_ifp->flush_timeout, &babel_now) < msecs) - return; - set_timeout(&babel_ifp->flush_timeout, msecs); -} - -static void -schedule_flush_now(struct interface *ifp) -{ - babel_interface_nfo *babel_ifp = babel_get_if_nfo(ifp); - /* Almost now */ - unsigned msecs = roughly(10); - if(babel_ifp->flush_timeout.tv_sec != 0 && - timeval_minus_msec(&babel_ifp->flush_timeout, &babel_now) < msecs) - return; - set_timeout(&babel_ifp->flush_timeout, msecs); -} - -static void -schedule_unicast_flush(unsigned msecs) -{ - if(!unicast_neighbour) - return; - if(unicast_flush_timeout.tv_sec != 0 && - timeval_minus_msec(&unicast_flush_timeout, &babel_now) < msecs) - return; - unicast_flush_timeout.tv_usec = (babel_now.tv_usec + msecs * 1000) %1000000; - unicast_flush_timeout.tv_sec = - babel_now.tv_sec + (babel_now.tv_usec / 1000 + msecs) / 1000; -} - -static void -ensure_space(struct interface *ifp, int space) -{ - babel_interface_nfo *babel_ifp = babel_get_if_nfo(ifp); - if(babel_ifp->bufsize - babel_ifp->buffered < space) - flushbuf(ifp); -} - -static void -start_message(struct interface *ifp, int type, int len) -{ - babel_interface_nfo *babel_ifp = babel_get_if_nfo(ifp); - if(babel_ifp->bufsize - babel_ifp->buffered < len + 2) - flushbuf(ifp); - babel_ifp->sendbuf[babel_ifp->buffered++] = type; - babel_ifp->sendbuf[babel_ifp->buffered++] = len; -} - -static void -end_message(struct interface *ifp, int type, int bytes) -{ - babel_interface_nfo *babel_ifp = babel_get_if_nfo(ifp); - assert(babel_ifp->buffered >= bytes + 2 && - babel_ifp->sendbuf[babel_ifp->buffered - bytes - 2] == type && - babel_ifp->sendbuf[babel_ifp->buffered - bytes - 1] == bytes); - schedule_flush(ifp); -} - -static void -accumulate_byte(struct interface *ifp, unsigned char value) -{ - babel_interface_nfo *babel_ifp = babel_get_if_nfo(ifp); - babel_ifp->sendbuf[babel_ifp->buffered++] = value; -} - -static void -accumulate_short(struct interface *ifp, unsigned short value) -{ - babel_interface_nfo *babel_ifp = babel_get_if_nfo(ifp); - DO_HTONS(babel_ifp->sendbuf + babel_ifp->buffered, value); - babel_ifp->buffered += 2; -} - -static void -accumulate_bytes(struct interface *ifp, - const unsigned char *value, unsigned len) -{ - babel_interface_nfo *babel_ifp = babel_get_if_nfo(ifp); - memcpy(babel_ifp->sendbuf + babel_ifp->buffered, value, len); - babel_ifp->buffered += len; -} - -static int -start_unicast_message(struct neighbour *neigh, int type, int len) -{ - if(unicast_neighbour) { - if(neigh != unicast_neighbour || - unicast_buffered + len + 2 >= - MIN(UNICAST_BUFSIZE, babel_get_if_nfo(neigh->ifp)->bufsize)) - flush_unicast(0); - } - if(!unicast_buffer) - unicast_buffer = malloc(UNICAST_BUFSIZE); - if(!unicast_buffer) { - zlog_err("malloc(unicast_buffer): %s", safe_strerror(errno)); - return -1; - } - - unicast_neighbour = neigh; - - unicast_buffer[unicast_buffered++] = type; - unicast_buffer[unicast_buffered++] = len; - return 1; -} - -static void -end_unicast_message(struct neighbour *neigh, int type, int bytes) -{ - assert(unicast_neighbour == neigh && unicast_buffered >= bytes + 2 && - unicast_buffer[unicast_buffered - bytes - 2] == type && - unicast_buffer[unicast_buffered - bytes - 1] == bytes); - schedule_unicast_flush(jitter(babel_get_if_nfo(neigh->ifp), 0)); -} - -static void -accumulate_unicast_byte(struct neighbour *neigh, unsigned char value) -{ - unicast_buffer[unicast_buffered++] = value; -} - -static void -accumulate_unicast_short(struct neighbour *neigh, unsigned short value) -{ - DO_HTONS(unicast_buffer + unicast_buffered, value); - unicast_buffered += 2; -} - -static void -accumulate_unicast_bytes(struct neighbour *neigh, - const unsigned char *value, unsigned len) -{ - memcpy(unicast_buffer + unicast_buffered, value, len); - unicast_buffered += len; -} - -void -send_ack(struct neighbour *neigh, unsigned short nonce, unsigned short interval) -{ - int rc; - debugf(BABEL_DEBUG_COMMON,"Sending ack (%04x) to %s on %s.", - nonce, format_address(neigh->address), neigh->ifp->name); - rc = start_unicast_message(neigh, MESSAGE_ACK, 2); if(rc < 0) return; - accumulate_unicast_short(neigh, nonce); - end_unicast_message(neigh, MESSAGE_ACK, 2); - /* Roughly yields a value no larger than 3/2, so this meets the deadline */ - schedule_unicast_flush(roughly(interval * 6)); -} - -void -send_hello_noupdate(struct interface *ifp, unsigned interval) -{ - babel_interface_nfo *babel_ifp = babel_get_if_nfo(ifp); - /* This avoids sending multiple hellos in a single packet, which breaks - link quality estimation. */ - if(babel_ifp->have_buffered_hello) - flushbuf(ifp); - - babel_ifp->hello_seqno = seqno_plus(babel_ifp->hello_seqno, 1); - set_timeout(&babel_ifp->hello_timeout, babel_ifp->hello_interval); - - if(!if_up(ifp)) - return; - - debugf(BABEL_DEBUG_COMMON,"Sending hello %d (%d) to %s.", - babel_ifp->hello_seqno, interval, ifp->name); - - start_message(ifp, MESSAGE_HELLO, 6); - accumulate_short(ifp, 0); - accumulate_short(ifp, babel_ifp->hello_seqno); - accumulate_short(ifp, interval > 0xFFFF ? 0xFFFF : interval); - end_message(ifp, MESSAGE_HELLO, 6); - babel_ifp->have_buffered_hello = 1; -} - -void -send_hello(struct interface *ifp) -{ - babel_interface_nfo *babel_ifp = babel_get_if_nfo(ifp); - send_hello_noupdate(ifp, (babel_ifp->hello_interval + 9) / 10); - /* Send full IHU every 3 hellos, and marginal IHU each time */ - if(babel_ifp->hello_seqno % 3 == 0) - send_ihu(NULL, ifp); - else - send_marginal_ihu(ifp); -} - -void -flush_unicast(int dofree) -{ - struct sockaddr_in6 sin6; - int rc; - - if(unicast_buffered == 0) - goto done; - - if(!if_up(unicast_neighbour->ifp)) - goto done; - - /* Preserve ordering of messages */ - flushbuf(unicast_neighbour->ifp); - - if(check_bucket(unicast_neighbour->ifp)) { - memset(&sin6, 0, sizeof(sin6)); - sin6.sin6_family = AF_INET6; - memcpy(&sin6.sin6_addr, unicast_neighbour->address, 16); - sin6.sin6_port = htons(protocol_port); - sin6.sin6_scope_id = unicast_neighbour->ifp->ifindex; - DO_HTONS(packet_header + 2, unicast_buffered); - rc = babel_send(protocol_socket, - packet_header, sizeof(packet_header), - unicast_buffer, unicast_buffered, - (struct sockaddr*)&sin6, sizeof(sin6)); - if(rc < 0) - zlog_err("send(unicast): %s", safe_strerror(errno)); - } else { - zlog_err("Warning: bucket full, dropping unicast packet to %s if %s.", - format_address(unicast_neighbour->address), - unicast_neighbour->ifp->name); - } - - done: - VALGRIND_MAKE_MEM_UNDEFINED(unicast_buffer, UNICAST_BUFSIZE); - unicast_buffered = 0; - if(dofree && unicast_buffer) { - free(unicast_buffer); - unicast_buffer = NULL; - } - unicast_neighbour = NULL; - unicast_flush_timeout.tv_sec = 0; - unicast_flush_timeout.tv_usec = 0; -} - -static void -really_send_update(struct interface *ifp, - const unsigned char *id, - const unsigned char *prefix, unsigned char plen, - unsigned short seqno, unsigned short metric, - unsigned char *channels, int channels_len) -{ - babel_interface_nfo *babel_ifp = babel_get_if_nfo(ifp); - int add_metric, v4, real_plen, omit = 0; - const unsigned char *real_prefix; - unsigned short flags = 0; - int channels_size; - - if(diversity_kind != DIVERSITY_CHANNEL) - channels_len = -1; - - channels_size = channels_len >= 0 ? channels_len + 2 : 0; - - if(!if_up(ifp)) - return; - - add_metric = output_filter(id, prefix, plen, ifp->ifindex); - if(add_metric >= INFINITY) - return; - - metric = MIN(metric + add_metric, INFINITY); - /* Worst case */ - ensure_space(ifp, 20 + 12 + 28); - - v4 = plen >= 96 && v4mapped(prefix); - - if(v4) { - if(!babel_ifp->ipv4) - return; - if(!babel_ifp->have_buffered_nh || - memcmp(babel_ifp->buffered_nh, babel_ifp->ipv4, 4) != 0) { - start_message(ifp, MESSAGE_NH, 6); - accumulate_byte(ifp, 1); - accumulate_byte(ifp, 0); - accumulate_bytes(ifp, babel_ifp->ipv4, 4); - end_message(ifp, MESSAGE_NH, 6); - memcpy(babel_ifp->buffered_nh, babel_ifp->ipv4, 4); - babel_ifp->have_buffered_nh = 1; - } - - real_prefix = prefix + 12; - real_plen = plen - 96; - } else { - if(babel_ifp->have_buffered_prefix) { - while(omit < plen / 8 && - babel_ifp->buffered_prefix[omit] == prefix[omit]) - omit++; - } - if(!babel_ifp->have_buffered_prefix || plen >= 48) - flags |= 0x80; - real_prefix = prefix; - real_plen = plen; - } - - if(!babel_ifp->have_buffered_id - || memcmp(id, babel_ifp->buffered_id, 8) != 0) { - if(real_plen == 128 && memcmp(real_prefix + 8, id, 8) == 0) { - flags |= 0x40; - } else { - start_message(ifp, MESSAGE_ROUTER_ID, 10); - accumulate_short(ifp, 0); - accumulate_bytes(ifp, id, 8); - end_message(ifp, MESSAGE_ROUTER_ID, 10); - } - memcpy(babel_ifp->buffered_id, id, 16); - babel_ifp->have_buffered_id = 1; - } - - start_message(ifp, MESSAGE_UPDATE, 10 + (real_plen + 7) / 8 - omit + - channels_size); - accumulate_byte(ifp, v4 ? 1 : 2); - accumulate_byte(ifp, flags); - accumulate_byte(ifp, real_plen); - accumulate_byte(ifp, omit); - accumulate_short(ifp, (babel_ifp->update_interval + 5) / 10); - accumulate_short(ifp, seqno); - accumulate_short(ifp, metric); - accumulate_bytes(ifp, real_prefix + omit, (real_plen + 7) / 8 - omit); - /* Note that an empty channels TLV is different from no such TLV. */ - if(channels_len >= 0) { - accumulate_byte(ifp, 2); - accumulate_byte(ifp, channels_len); - accumulate_bytes(ifp, channels, channels_len); - } - end_message(ifp, MESSAGE_UPDATE, 10 + (real_plen + 7) / 8 - omit + - channels_size); - - if(flags & 0x80) { - memcpy(babel_ifp->buffered_prefix, prefix, 16); - babel_ifp->have_buffered_prefix = 1; - } -} - -static int -compare_buffered_updates(const void *av, const void *bv) -{ - const struct buffered_update *a = av, *b = bv; - int rc, v4a, v4b, ma, mb; - - rc = memcmp(a->id, b->id, 8); - if(rc != 0) - return rc; - - v4a = (a->plen >= 96 && v4mapped(a->prefix)); - v4b = (b->plen >= 96 && v4mapped(b->prefix)); - - if(v4a > v4b) - return 1; - else if(v4a < v4b) - return -1; - - ma = (!v4a && a->plen == 128 && memcmp(a->prefix + 8, a->id, 8) == 0); - mb = (!v4b && b->plen == 128 && memcmp(b->prefix + 8, b->id, 8) == 0); - - if(ma > mb) - return -1; - else if(mb > ma) - return 1; - - if(a->plen < b->plen) - return 1; - else if(a->plen > b->plen) - return -1; - - return memcmp(a->prefix, b->prefix, 16); -} - -void -flushupdates(struct interface *ifp) -{ - babel_interface_nfo *babel_ifp = NULL; - struct xroute *xroute; - struct babel_route *route; - const unsigned char *last_prefix = NULL; - unsigned char last_plen = 0xFF; - int i; - - if(ifp == NULL) { - struct interface *ifp_aux; - struct listnode *linklist_node = NULL; - FOR_ALL_INTERFACES(ifp_aux, linklist_node) - flushupdates(ifp_aux); - return; - } - - babel_ifp = babel_get_if_nfo(ifp); - if(babel_ifp->num_buffered_updates > 0) { - struct buffered_update *b = babel_ifp->buffered_updates; - int n = babel_ifp->num_buffered_updates; - - babel_ifp->buffered_updates = NULL; - babel_ifp->update_bufsize = 0; - babel_ifp->num_buffered_updates = 0; - - if(!if_up(ifp)) - goto done; - - debugf(BABEL_DEBUG_COMMON," (flushing %d buffered updates on %s (%d))", - n, ifp->name, ifp->ifindex); - - /* In order to send fewer update messages, we want to send updates - with the same router-id together, with IPv6 going out before IPv4. */ - - for(i = 0; i < n; i++) { - route = find_installed_route(b[i].prefix, b[i].plen); - if(route) - memcpy(b[i].id, route->src->id, 8); - else - memcpy(b[i].id, myid, 8); - } - - qsort(b, n, sizeof(struct buffered_update), compare_buffered_updates); - - for(i = 0; i < n; i++) { - /* The same update may be scheduled multiple times before it is - sent out. Since our buffer is now sorted, it is enough to - compare with the previous update. */ - - if(last_prefix) { - if(b[i].plen == last_plen && - memcmp(b[i].prefix, last_prefix, 16) == 0) - continue; - } - - xroute = find_xroute(b[i].prefix, b[i].plen); - route = find_installed_route(b[i].prefix, b[i].plen); - - if(xroute && (!route || xroute->metric <= kernel_metric)) { - really_send_update(ifp, myid, - xroute->prefix, xroute->plen, - myseqno, xroute->metric, - NULL, 0); - last_prefix = xroute->prefix; - last_plen = xroute->plen; - } else if(route) { - unsigned char channels[DIVERSITY_HOPS]; - int chlen; - struct interface *route_ifp = route->neigh->ifp; - struct babel_interface *babel_route_ifp = NULL; - unsigned short metric; - unsigned short seqno; - - seqno = route->seqno; - metric = - route_interferes(route, ifp) ? - route_metric(route) : - route_metric_noninterfering(route); - - if(metric < INFINITY) - satisfy_request(route->src->prefix, route->src->plen, - seqno, route->src->id, ifp); - if((babel_ifp->flags & BABEL_IF_SPLIT_HORIZON) && - route->neigh->ifp == ifp) - continue; - - babel_route_ifp = babel_get_if_nfo(route_ifp); - if(babel_route_ifp->channel ==BABEL_IF_CHANNEL_NONINTERFERING) { - memcpy(channels, route->channels, DIVERSITY_HOPS); - } else { - if(babel_route_ifp->channel == BABEL_IF_CHANNEL_UNKNOWN) - channels[0] = BABEL_IF_CHANNEL_INTERFERING; - else { - assert(babel_route_ifp->channel > 0 && - babel_route_ifp->channel <= 255); - channels[0] = babel_route_ifp->channel; - } - memcpy(channels + 1, route->channels, DIVERSITY_HOPS - 1); - } - - chlen = channels_len(channels); - really_send_update(ifp, route->src->id, - route->src->prefix, - route->src->plen, - seqno, metric, - channels, chlen); - update_source(route->src, seqno, metric); - last_prefix = route->src->prefix; - last_plen = route->src->plen; - } else { - /* There's no route for this prefix. This can happen shortly - after an xroute has been retracted, so send a retraction. */ - really_send_update(ifp, myid, b[i].prefix, b[i].plen, - myseqno, INFINITY, NULL, -1); - } - } - schedule_flush_now(ifp); - done: - free(b); - } - babel_ifp->update_flush_timeout.tv_sec = 0; - babel_ifp->update_flush_timeout.tv_usec = 0; -} - -static void -schedule_update_flush(struct interface *ifp, int urgent) -{ - babel_interface_nfo *babel_ifp = babel_get_if_nfo(ifp); - unsigned msecs; - msecs = update_jitter(babel_ifp, urgent); - if(babel_ifp->update_flush_timeout.tv_sec != 0 && - timeval_minus_msec(&babel_ifp->update_flush_timeout, &babel_now) < msecs) - return; - set_timeout(&babel_ifp->update_flush_timeout, msecs); -} - -static void -buffer_update(struct interface *ifp, - const unsigned char *prefix, unsigned char plen) -{ - babel_interface_nfo *babel_ifp = babel_get_if_nfo(ifp); - if(babel_ifp->num_buffered_updates > 0 && - babel_ifp->num_buffered_updates >= babel_ifp->update_bufsize) - flushupdates(ifp); - - if(babel_ifp->update_bufsize == 0) { - int n; - assert(babel_ifp->buffered_updates == NULL); - /* Allocate enough space to hold a full update. Since the - number of installed routes will grow over time, make sure we - have enough space to send a full-ish frame. */ - n = installed_routes_estimate() + xroutes_estimate() + 4; - n = MAX(n, babel_ifp->bufsize / 16); - again: - babel_ifp->buffered_updates = malloc(n *sizeof(struct buffered_update)); - if(babel_ifp->buffered_updates == NULL) { - zlog_err("malloc(buffered_updates): %s", safe_strerror(errno)); - if(n > 4) { - /* Try again with a tiny buffer. */ - n = 4; - goto again; - } - return; - } - babel_ifp->update_bufsize = n; - babel_ifp->num_buffered_updates = 0; - } - - memcpy(babel_ifp->buffered_updates[babel_ifp->num_buffered_updates].prefix, - prefix, 16); - babel_ifp->buffered_updates[babel_ifp->num_buffered_updates].plen = plen; - babel_ifp->num_buffered_updates++; -} - -static void -buffer_update_callback(struct babel_route *route, void *closure) -{ - buffer_update((struct interface*)closure, - route->src->prefix, route->src->plen); -} - -void -send_update(struct interface *ifp, int urgent, - const unsigned char *prefix, unsigned char plen) -{ - babel_interface_nfo *babel_ifp = NULL; - - if(ifp == NULL) { - struct interface *ifp_aux; - struct listnode *linklist_node = NULL; - struct babel_route *route; - FOR_ALL_INTERFACES(ifp_aux, linklist_node) - send_update(ifp_aux, urgent, prefix, plen); - if(prefix) { - /* Since flushupdates only deals with non-wildcard interfaces, we - need to do this now. */ - route = find_installed_route(prefix, plen); - if(route && route_metric(route) < INFINITY) - satisfy_request(prefix, plen, route->src->seqno, route->src->id, - NULL); - } - return; - } - - if(!if_up(ifp)) - return; - - babel_ifp = babel_get_if_nfo(ifp); - if(prefix) { - debugf(BABEL_DEBUG_COMMON,"Sending update to %s for %s.", - ifp->name, format_prefix(prefix, plen)); - buffer_update(ifp, prefix, plen); - } else { - send_self_update(ifp); - debugf(BABEL_DEBUG_COMMON,"Sending update to %s for any.", ifp->name); - for_all_installed_routes(buffer_update_callback, ifp); - set_timeout(&babel_ifp->update_timeout, babel_ifp->update_interval); - babel_ifp->last_update_time = babel_now.tv_sec; - } - schedule_update_flush(ifp, urgent); -} - -void -send_update_resend(struct interface *ifp, - const unsigned char *prefix, unsigned char plen) -{ - assert(prefix != NULL); - - send_update(ifp, 1, prefix, plen); - record_resend(RESEND_UPDATE, prefix, plen, 0, 0, NULL, resend_delay); -} - -void -send_wildcard_retraction(struct interface *ifp) -{ - babel_interface_nfo *babel_ifp = NULL; - if(ifp == NULL) { - struct interface *ifp_aux; - struct listnode *linklist_node = NULL; - FOR_ALL_INTERFACES(ifp_aux, linklist_node) - send_wildcard_retraction(ifp_aux); - return; - } - - if(!if_up(ifp)) - return; - - babel_ifp = babel_get_if_nfo(ifp); - start_message(ifp, MESSAGE_UPDATE, 10); - accumulate_byte(ifp, 0); - accumulate_byte(ifp, 0x40); - accumulate_byte(ifp, 0); - accumulate_byte(ifp, 0); - accumulate_short(ifp, 0xFFFF); - accumulate_short(ifp, myseqno); - accumulate_short(ifp, 0xFFFF); - end_message(ifp, MESSAGE_UPDATE, 10); - - babel_ifp->have_buffered_id = 0; -} - -void -update_myseqno() -{ - myseqno = seqno_plus(myseqno, 1); - seqno_time = babel_now; -} - -static void -send_xroute_update_callback(struct xroute *xroute, void *closure) -{ - struct interface *ifp = (struct interface*)closure; - send_update(ifp, 0, xroute->prefix, xroute->plen); -} - -void -send_self_update(struct interface *ifp) -{ - if(ifp == NULL) { - struct interface *ifp_aux; - struct listnode *linklist_node = NULL; - FOR_ALL_INTERFACES(ifp_aux, linklist_node) { - if(!if_up(ifp_aux)) - continue; - send_self_update(ifp_aux); - } - return; - } - - debugf(BABEL_DEBUG_COMMON,"Sending self update to %s.", ifp->name); - for_all_xroutes(send_xroute_update_callback, ifp); -} - -void -send_ihu(struct neighbour *neigh, struct interface *ifp) -{ - babel_interface_nfo *babel_ifp = NULL; - int rxcost, interval; - int ll; - - if(neigh == NULL && ifp == NULL) { - struct interface *ifp_aux; - struct listnode *linklist_node = NULL; - FOR_ALL_INTERFACES(ifp_aux, linklist_node) { - if(if_up(ifp_aux)) - continue; - send_ihu(NULL, ifp_aux); - } - return; - } - - if(neigh == NULL) { - struct neighbour *ngh; - FOR_ALL_NEIGHBOURS(ngh) { - if(ngh->ifp == ifp) - send_ihu(ngh, ifp); - } - return; - } - - - if(ifp && neigh->ifp != ifp) - return; - - ifp = neigh->ifp; - babel_ifp = babel_get_if_nfo(ifp); - if(!if_up(ifp)) - return; - - rxcost = neighbour_rxcost(neigh); - interval = (babel_ifp->hello_interval * 3 + 9) / 10; - - /* Conceptually, an IHU is a unicast message. We usually send them as - multicast, since this allows aggregation into a single packet and - avoids an ARP exchange. If we already have a unicast message queued - for this neighbour, however, we might as well piggyback the IHU. */ - debugf(BABEL_DEBUG_COMMON,"Sending %sihu %d on %s to %s.", - unicast_neighbour == neigh ? "unicast " : "", - rxcost, - neigh->ifp->name, - format_address(neigh->address)); - - ll = linklocal(neigh->address); - - if(unicast_neighbour != neigh) { - start_message(ifp, MESSAGE_IHU, ll ? 14 : 22); - accumulate_byte(ifp, ll ? 3 : 2); - accumulate_byte(ifp, 0); - accumulate_short(ifp, rxcost); - accumulate_short(ifp, interval); - if(ll) - accumulate_bytes(ifp, neigh->address + 8, 8); - else - accumulate_bytes(ifp, neigh->address, 16); - end_message(ifp, MESSAGE_IHU, ll ? 14 : 22); - } else { - int rc; - rc = start_unicast_message(neigh, MESSAGE_IHU, ll ? 14 : 22); - if(rc < 0) return; - accumulate_unicast_byte(neigh, ll ? 3 : 2); - accumulate_unicast_byte(neigh, 0); - accumulate_unicast_short(neigh, rxcost); - accumulate_unicast_short(neigh, interval); - if(ll) - accumulate_unicast_bytes(neigh, neigh->address + 8, 8); - else - accumulate_unicast_bytes(neigh, neigh->address, 16); - end_unicast_message(neigh, MESSAGE_IHU, ll ? 14 : 22); - } -} - -/* Send IHUs to all marginal neighbours */ -void -send_marginal_ihu(struct interface *ifp) -{ - struct neighbour *neigh; - FOR_ALL_NEIGHBOURS(neigh) { - if(ifp && neigh->ifp != ifp) - continue; - if(neigh->txcost >= 384 || (neigh->reach & 0xF000) != 0xF000) - send_ihu(neigh, ifp); - } -} - -void -send_request(struct interface *ifp, - const unsigned char *prefix, unsigned char plen) -{ - int v4, len; - - if(ifp == NULL) { - struct interface *ifp_aux; - struct listnode *linklist_node = NULL; - FOR_ALL_INTERFACES(ifp_aux, linklist_node) { - if(if_up(ifp_aux)) - continue; - send_request(ifp_aux, prefix, plen); - } - return; - } - - /* make sure any buffered updates go out before this request. */ - flushupdates(ifp); - - if(!if_up(ifp)) - return; - - debugf(BABEL_DEBUG_COMMON,"sending request to %s for %s.", - ifp->name, prefix ? format_prefix(prefix, plen) : "any"); - v4 = plen >= 96 && v4mapped(prefix); - len = !prefix ? 2 : v4 ? 6 : 18; - - start_message(ifp, MESSAGE_REQUEST, len); - accumulate_byte(ifp, !prefix ? 0 : v4 ? 1 : 2); - accumulate_byte(ifp, !prefix ? 0 : v4 ? plen - 96 : plen); - if(prefix) { - if(v4) - accumulate_bytes(ifp, prefix + 12, 4); - else - accumulate_bytes(ifp, prefix, 16); - } - end_message(ifp, MESSAGE_REQUEST, len); -} - -void -send_unicast_request(struct neighbour *neigh, - const unsigned char *prefix, unsigned char plen) -{ - int rc, v4, len; - - /* make sure any buffered updates go out before this request. */ - flushupdates(neigh->ifp); - - debugf(BABEL_DEBUG_COMMON,"sending unicast request to %s for %s.", - format_address(neigh->address), - prefix ? format_prefix(prefix, plen) : "any"); - v4 = plen >= 96 && v4mapped(prefix); - len = !prefix ? 2 : v4 ? 6 : 18; - - rc = start_unicast_message(neigh, MESSAGE_REQUEST, len); - if(rc < 0) return; - accumulate_unicast_byte(neigh, !prefix ? 0 : v4 ? 1 : 2); - accumulate_unicast_byte(neigh, !prefix ? 0 : v4 ? plen - 96 : plen); - if(prefix) { - if(v4) - accumulate_unicast_bytes(neigh, prefix + 12, 4); - else - accumulate_unicast_bytes(neigh, prefix, 16); - } - end_unicast_message(neigh, MESSAGE_REQUEST, len); -} - -void -send_multihop_request(struct interface *ifp, - const unsigned char *prefix, unsigned char plen, - unsigned short seqno, const unsigned char *id, - unsigned short hop_count) -{ - int v4, pb, len; - - /* Make sure any buffered updates go out before this request. */ - flushupdates(ifp); - - if(ifp == NULL) { - struct interface *ifp_aux; - struct listnode *linklist_node = NULL; - FOR_ALL_INTERFACES(ifp_aux, linklist_node) { - if(!if_up(ifp_aux)) - continue; - send_multihop_request(ifp_aux, prefix, plen, seqno, id, hop_count); - } - return; - } - - if(!if_up(ifp)) - return; - - debugf(BABEL_DEBUG_COMMON,"Sending request (%d) on %s for %s.", - hop_count, ifp->name, format_prefix(prefix, plen)); - v4 = plen >= 96 && v4mapped(prefix); - pb = v4 ? ((plen - 96) + 7) / 8 : (plen + 7) / 8; - len = 6 + 8 + pb; - - start_message(ifp, MESSAGE_MH_REQUEST, len); - accumulate_byte(ifp, v4 ? 1 : 2); - accumulate_byte(ifp, v4 ? plen - 96 : plen); - accumulate_short(ifp, seqno); - accumulate_byte(ifp, hop_count); - accumulate_byte(ifp, 0); - accumulate_bytes(ifp, id, 8); - if(prefix) { - if(v4) - accumulate_bytes(ifp, prefix + 12, pb); - else - accumulate_bytes(ifp, prefix, pb); - } - end_message(ifp, MESSAGE_MH_REQUEST, len); -} - -void -send_unicast_multihop_request(struct neighbour *neigh, - const unsigned char *prefix, unsigned char plen, - unsigned short seqno, const unsigned char *id, - unsigned short hop_count) -{ - int rc, v4, pb, len; - - /* Make sure any buffered updates go out before this request. */ - flushupdates(neigh->ifp); - - debugf(BABEL_DEBUG_COMMON,"Sending multi-hop request to %s for %s (%d hops).", - format_address(neigh->address), - format_prefix(prefix, plen), hop_count); - v4 = plen >= 96 && v4mapped(prefix); - pb = v4 ? ((plen - 96) + 7) / 8 : (plen + 7) / 8; - len = 6 + 8 + pb; - - rc = start_unicast_message(neigh, MESSAGE_MH_REQUEST, len); - if(rc < 0) return; - accumulate_unicast_byte(neigh, v4 ? 1 : 2); - accumulate_unicast_byte(neigh, v4 ? plen - 96 : plen); - accumulate_unicast_short(neigh, seqno); - accumulate_unicast_byte(neigh, hop_count); - accumulate_unicast_byte(neigh, 0); - accumulate_unicast_bytes(neigh, id, 8); - if(prefix) { - if(v4) - accumulate_unicast_bytes(neigh, prefix + 12, pb); - else - accumulate_unicast_bytes(neigh, prefix, pb); - } - end_unicast_message(neigh, MESSAGE_MH_REQUEST, len); -} - -void -send_request_resend(struct neighbour *neigh, - const unsigned char *prefix, unsigned char plen, - unsigned short seqno, unsigned char *id) -{ - if(neigh) - send_unicast_multihop_request(neigh, prefix, plen, seqno, id, 127); - else - send_multihop_request(NULL, prefix, plen, seqno, id, 127); - - record_resend(RESEND_REQUEST, prefix, plen, seqno, id, - neigh ? neigh->ifp : NULL, resend_delay); -} - -void -handle_request(struct neighbour *neigh, const unsigned char *prefix, - unsigned char plen, unsigned char hop_count, - unsigned short seqno, const unsigned char *id) -{ - struct xroute *xroute; - struct babel_route *route; - struct neighbour *successor = NULL; - - xroute = find_xroute(prefix, plen); - route = find_installed_route(prefix, plen); - - if(xroute && (!route || xroute->metric <= kernel_metric)) { - if(hop_count > 0 && memcmp(id, myid, 8) == 0) { - if(seqno_compare(seqno, myseqno) > 0) { - if(seqno_minus(seqno, myseqno) > 100) { - /* Hopelessly out-of-date request */ - return; - } - update_myseqno(); - } - } - send_update(neigh->ifp, 1, prefix, plen); - return; - } - - if(route && - (memcmp(id, route->src->id, 8) != 0 || - seqno_compare(seqno, route->seqno) <= 0)) { - send_update(neigh->ifp, 1, prefix, plen); - return; - } - - if(hop_count <= 1) - return; - - if(route && memcmp(id, route->src->id, 8) == 0 && - seqno_minus(seqno, route->seqno) > 100) { - /* Hopelessly out-of-date */ - return; - } - - if(request_redundant(neigh->ifp, prefix, plen, seqno, id)) - return; - - /* Let's try to forward this request. */ - if(route && route_metric(route) < INFINITY) - successor = route->neigh; - - if(!successor || successor == neigh) { - /* We were about to forward a request to its requestor. Try to - find a different neighbour to forward the request to. */ - struct babel_route *other_route; - - other_route = find_best_route(prefix, plen, 0, neigh); - if(other_route && route_metric(other_route) < INFINITY) - successor = other_route->neigh; - } - - if(!successor || successor == neigh) - /* Give up */ - return; - - send_unicast_multihop_request(successor, prefix, plen, seqno, id, - hop_count - 1); - record_resend(RESEND_REQUEST, prefix, plen, seqno, id, - neigh->ifp, 0); -} |