/* *------------------------------------------------------------------ * Copyright (c) 2017 Cisco and/or its affiliates. * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at: * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. *------------------------------------------------------------------ */ #include <igmp/igmp_pkt.h> #include <vnet/fib/fib_sas.h> static void vlib_buffer_append (vlib_buffer_t * b, uword l) { b->current_data += l; b->current_length += l; } static vlib_buffer_t * igmp_pkt_get_buffer (igmp_pkt_build_t * bk) { vlib_main_t *vm; vlib_buffer_t *b; u32 bi; vm = vlib_get_main (); if (vlib_buffer_alloc (vm, &bi, 1) != 1) return (NULL); b = vlib_get_buffer (vm, bi); b->flags |= VNET_BUFFER_F_LOCALLY_ORIGINATED; b->flags |= VLIB_BUFFER_IS_TRACED; /* clear out stale data */ vnet_buffer (b)->sw_if_index[VLIB_RX] = ~0; /* * save progress in the builder */ vec_add1 (bk->buffers, bi); bk->n_avail = vnet_sw_interface_get_mtu (vnet_get_main (), bk->sw_if_index, VNET_MTU_IP4); return (b); } static vlib_buffer_t * igmp_pkt_build_ip_header (igmp_pkt_build_t * bk, igmp_msg_type_t msg_type, const igmp_group_t * group) { ip4_header_t *ip4; vlib_buffer_t *b; u8 *option; b = igmp_pkt_get_buffer (bk); if (NULL == b) return (NULL); ip4 = vlib_buffer_get_current (b); clib_memset (ip4, 0, sizeof (ip4_header_t)); ip4->ip_version_and_header_length = 0x46; ip4->ttl = 1; ip4->protocol = IP_PROTOCOL_IGMP; ip4->tos = 0xc0; fib_sas4_get (bk->sw_if_index, NULL, &ip4->src_address); vlib_buffer_append (b, sizeof (*ip4)); bk->n_avail -= sizeof (*ip4); switch (msg_type) { case IGMP_MSG_REPORT: ip4->dst_address.as_u32 = IGMP_MEMBERSHIP_REPORT_ADDRESS; break; case IGMP_MSG_QUERY: if (group != NULL) clib_memcpy_fast (&ip4->dst_address, &group->key->ip4, sizeof (ip4_address_t)); else ip4->dst_address.as_u32 = IGMP_GENERAL_QUERY_ADDRESS; break; } /* add the router alert options */ option = vlib_buffer_get_current (b); option[0] = 0x80 | 20; // IP4_ROUTER_ALERT_OPTION; option[1] = 4; // length option[2] = option[3] = 0; vlib_buffer_append (b, 4); bk->n_avail -= 4; return (b); } static vlib_buffer_t * igmp_pkt_build_report_v3 (igmp_pkt_build_report_t * br, const igmp_group_t * group) { igmp_membership_report_v3_t *report; vlib_buffer_t *b; b = igmp_pkt_build_ip_header (&br->base, IGMP_MSG_REPORT, group); if (NULL == b) return (NULL); report = vlib_buffer_get_current (b); report->header.type = IGMP_TYPE_membership_report_v3; report->header.code = 0; report->header.checksum = 0; report->unused = 0; vlib_buffer_append (b, sizeof (igmp_membership_report_v3_t)); br->base.n_avail -= sizeof (igmp_membership_report_v3_t); br->base.n_bytes += sizeof (igmp_membership_report_v3_t); return (b); } static void igmp_pkt_tx (igmp_pkt_build_t * bk) { const igmp_config_t *config; vlib_buffer_t *b; vlib_main_t *vm; vlib_frame_t *f; u32 *to_next; u32 ii; vm = vlib_get_main (); config = igmp_config_lookup (bk->sw_if_index); if (NULL == config) return; f = vlib_get_frame_to_node (vm, ip4_rewrite_mcast_node.index); to_next = vlib_frame_vector_args (f); vec_foreach_index (ii, bk->buffers) { b = vlib_get_buffer (vm, bk->buffers[ii]); vnet_buffer (b)->ip.adj_index[VLIB_TX] = config->adj_index; to_next[ii] = bk->buffers[ii]; f->n_vectors++; } vlib_put_frame_to_node (vm, ip4_rewrite_mcast_node.index, f); IGMP_DBG (" ..tx: %U", format_vnet_sw_if_index_name, vnet_get_main (), bk->sw_if_index); vec_free (bk->buffers); bk->buffers = 0; } static vlib_buffer_t * igmp_pkt_build_report_get_active (igmp_pkt_build_report_t * br) { if (NULL == br->base.buffers) return (NULL); return (vlib_get_buffer (vlib_get_main (), br->base.buffers[vec_len (br->base.buffers) - 1])); } static void igmp_pkt_build_report_bake (igmp_pkt_build_report_t * br) { igmp_membership_report_v3_t *igmp; ip4_header_t *ip4; vlib_buffer_t *b; b = igmp_pkt_build_report_get_active (br); b->current_data = 0; ip4 = vlib_buffer_get_current (b); igmp = (igmp_membership_report_v3_t *) (((u32 *) ip4) + 6); igmp->n_groups = clib_host_to_net_u16 (br->n_groups); igmp->header.checksum = ~ip_csum_fold (ip_incremental_checksum (0, igmp, br->base.n_bytes)); ip4->length = clib_host_to_net_u16 (b->current_length); ip4->checksum = ip4_header_checksum (ip4); br->base.n_bytes = br->base.n_avail = br->n_groups = 0; } void igmp_pkt_report_v3_send (igmp_pkt_build_report_t * br) { if (NULL == br->base.buffers) return; igmp_pkt_build_report_bake (br); igmp_pkt_tx (&br->base); } static u32 igmp_pkt_report_v3_get_size (const igmp_group_t * group) { ASSERT (IGMP_FILTER_MODE_INCLUDE == group->router_filter_mode); return ((hash_elts (group->igmp_src_by_key[IGMP_FILTER_MODE_INCLUDE]) * sizeof (ip4_address_t)) + sizeof (igmp_membership_group_v3_t)); } static igmp_membership_group_v3_t * igmp_pkt_report_v3_append_group (igmp_pkt_build_report_t * br, const ip46_address_t * grp, igmp_membership_group_v3_type_t type) { igmp_membership_group_v3_t *igmp_group; vlib_buffer_t *b; b = igmp_pkt_build_report_get_active (br); if (br->base.n_avail < sizeof (igmp_membership_group_v3_t)) { igmp_pkt_build_report_bake (br); b = igmp_pkt_build_report_v3 (br, NULL); if (NULL == b) return (NULL); } br->base.n_avail -= sizeof (igmp_membership_group_v3_t); br->base.n_bytes += sizeof (igmp_membership_group_v3_t); br->n_groups++; br->n_srcs = 0; igmp_group = vlib_buffer_get_current (b); vlib_buffer_append (b, sizeof (igmp_membership_group_v3_t)); igmp_group->type = type; igmp_group->n_aux_u32s = 0; igmp_group->n_src_addresses = 0; igmp_group->group_address.as_u32 = grp->ip4.as_u32; return (igmp_group); } /** * 4.2.16 " If the set of Group Records required in a Report does not fit within * the size limit of a single Report message (as determined by the MTU * of the network on which it will be sent), the Group Records are sent * in as many Report messages as needed to report the entire set. * If a single Group Record contains so many source addresses that it * does not fit within the size limit of a single Report message, if its * Type is not MODE_IS_EXCLUDE or CHANGE_TO_EXCLUDE_MODE, it is split * into multiple Group Records, each containing a different subset of * the source addresses and each sent in a separate Report message. If * its Type is MODE_IS_EXCLUDE or CHANGE_TO_EXCLUDE_MODE, a single Group * Record is sent, containing as many source addresses as can fit, and * the remaining source addresses are not reported; though the choice of * which sources to report is arbitrary, it is preferable to report the * same set of sources in each subsequent report, rather than reporting * different sources each time." */ static igmp_membership_group_v3_t * igmp_pkt_report_v3_append_src (igmp_pkt_build_report_t * br, igmp_membership_group_v3_t * igmp_group, const ip46_address_t * grp, igmp_membership_group_v3_type_t type, const ip46_address_t * src) { vlib_buffer_t *b; b = igmp_pkt_build_report_get_active (br); if (br->base.n_avail < sizeof (ip4_address_t)) { igmp_group->n_src_addresses = clib_host_to_net_u16 (br->n_srcs); igmp_pkt_build_report_bake (br); b = igmp_pkt_build_report_v3 (br, NULL); if (NULL == b) return (NULL); igmp_group = igmp_pkt_report_v3_append_group (br, grp, type); } igmp_group->src_addresses[br->n_srcs].as_u32 = src->ip4.as_u32; br->n_srcs++; br->base.n_avail -= sizeof (ip4_address_t); br->base.n_bytes += sizeof (ip4_address_t); vlib_buffer_append (b, sizeof (ip4_address_t)); return (igmp_group); } void igmp_pkt_report_v3_add_report (igmp_pkt_build_report_t * br, const ip46_address_t * grp, const ip46_address_t * srcs, igmp_membership_group_v3_type_t type) { igmp_membership_group_v3_t *igmp_group; const ip46_address_t *s; vlib_buffer_t *b; b = igmp_pkt_build_report_get_active (br); if (NULL == b) { b = igmp_pkt_build_report_v3 (br, NULL); if (NULL == b) /* failed to allocate buffer */ return; } igmp_group = igmp_pkt_report_v3_append_group (br, grp, type); if (NULL == igmp_group) return; /* *INDENT-OFF* */ vec_foreach(s, srcs) { igmp_group = igmp_pkt_report_v3_append_src(br, igmp_group, grp, type, s); if (NULL == igmp_group) return; }; /* *INDENT-ON* */ igmp_group->n_src_addresses = clib_host_to_net_u16 (br->n_srcs); IGMP_DBG (" ..add-group: %U", format_ip46_address, grp, IP46_TYPE_IP4); } void igmp_pkt_report_v3_add_group (igmp_pkt_build_report_t * br, const igmp_group_t * group, igmp_membership_group_v3_type_t type) { igmp_membership_group_v3_t *igmp_group; vlib_buffer_t *b; igmp_src_t *src; b = igmp_pkt_build_report_get_active (br); if (NULL == b) { b = igmp_pkt_build_report_v3 (br, NULL); if (NULL == b) /* failed to allocate buffer */ return; } /* * if the group won't fit in a partially full buffer, start again */ if ((0 != br->n_groups) && (igmp_pkt_report_v3_get_size (group) > br->base.n_avail)) { igmp_pkt_build_report_bake (br); b = igmp_pkt_build_report_v3 (br, NULL); if (NULL == b) /* failed to allocate buffer */ return; } igmp_group = igmp_pkt_report_v3_append_group (br, group->key, type); /* *INDENT-OFF* */ FOR_EACH_SRC (src, group, IGMP_FILTER_MODE_INCLUDE, ({ igmp_group = igmp_pkt_report_v3_append_src(br, igmp_group, group->key, type, src->key); if (NULL == igmp_group) return; })); /* *INDENT-ON* */ igmp_group->n_src_addresses = clib_host_to_net_u16 (br->n_srcs); IGMP_DBG (" ..add-group: %U srcs:%d", format_igmp_key, group->key, hash_elts (group->igmp_src_by_key[IGMP_FILTER_MODE_INCLUDE])); } void igmp_pkt_build_report_init (igmp_pkt_build_report_t * br, u32 sw_if_index) { clib_memset (br, 0, sizeof (*br)); br->base.sw_if_index = sw_if_index; } static vlib_buffer_t * igmp_pkt_build_query_get_active (igmp_pkt_build_query_t * bq) { if (NULL == bq->base.buffers) return (NULL); return (vlib_get_buffer (vlib_get_main (), bq->base.buffers[vec_len (bq->base.buffers) - 1])); } static vlib_buffer_t * igmp_pkt_build_query_v3 (igmp_pkt_build_query_t * bq, const igmp_group_t * group) { igmp_membership_query_v3_t *query; vlib_buffer_t *b; b = igmp_pkt_build_ip_header (&bq->base, IGMP_MSG_QUERY, group); if (NULL == b) return (NULL); query = vlib_buffer_get_current (b); query->header.type = IGMP_TYPE_membership_query; query->header.code = 0; query->header.checksum = 0; query->qqi_code = 0; query->resv_s_qrv = 0; if (NULL != group) query->group_address.as_u32 = group->key->ip4.as_u32; else query->group_address.as_u32 = 0; vlib_buffer_append (b, sizeof (igmp_membership_query_v3_t)); bq->base.n_avail -= sizeof (igmp_membership_query_v3_t); bq->base.n_bytes += sizeof (igmp_membership_query_v3_t); return (b); } void igmp_pkt_query_v3_add_group (igmp_pkt_build_query_t * bq, const igmp_group_t * group, const ip46_address_t * srcs) { vlib_buffer_t *b; b = igmp_pkt_build_query_get_active (bq); if (NULL == b) { b = igmp_pkt_build_query_v3 (bq, group); if (NULL == b) /* failed to allocate buffer */ return; } if (NULL != srcs) { igmp_membership_query_v3_t *query; const ip46_address_t *src; query = vlib_buffer_get_current (b); vec_foreach (src, srcs) { query->src_addresses[bq->n_srcs++].as_u32 = src->ip4.as_u32; vlib_buffer_append (b, sizeof (ip4_address_t)); bq->base.n_bytes += sizeof (ip4_address_t); bq->base.n_avail += sizeof (ip4_address_t); } } /* * else * general query and we're done */ } static void igmp_pkt_build_query_bake (igmp_pkt_build_query_t * bq) { igmp_membership_query_v3_t *igmp; ip4_header_t *ip4; vlib_buffer_t *b; b = igmp_pkt_build_query_get_active (bq); b->current_data = 0; ip4 = vlib_buffer_get_current (b); // account for options igmp = (igmp_membership_query_v3_t *) (((u32 *) ip4) + 6); igmp->n_src_addresses = clib_host_to_net_u16 (bq->n_srcs); igmp->header.checksum = ~ip_csum_fold (ip_incremental_checksum (0, igmp, bq->base.n_bytes)); ip4->length = clib_host_to_net_u16 (b->current_length); ip4->checksum = ip4_header_checksum (ip4); bq->base.n_bytes = bq->base.n_avail = bq->n_srcs = 0; } void igmp_pkt_query_v3_send (igmp_pkt_build_query_t * bq) { if (NULL == bq->base.buffers) return; igmp_pkt_build_query_bake (bq); igmp_pkt_tx (&bq->base); } void igmp_pkt_build_query_init (igmp_pkt_build_query_t * bq, u32 sw_if_index) { clib_memset (bq, 0, sizeof (*bq)); bq->base.sw_if_index = sw_if_index; } /* * fd.io coding-style-patch-verification: ON * * Local Variables: * eval: (c-set-style "gnu") * End: */