From cbe25aab3be72154f2c706c39eeba6a77f34450f Mon Sep 17 00:00:00 2001 From: Neale Ranns Date: Mon, 30 Sep 2019 10:53:31 +0000 Subject: ip: Protocol Independent IP Neighbors Type: feature - ip-neighbour: generic neighbour handling; APIs, DBs, event handling, aging - arp: ARP protocol implementation - ip6-nd; IPv6 neighbor discovery implementation; separate ND, MLD, RA - ip6-link; manage link-local addresses - l2-arp-term; events separated from IP neighbours, since they are not the same. vnet retains just enough education to perform ND/ARP packet construction. arp and ip6-nd to be moved to plugins soon. Change-Id: I88dedd0006b299344f4c7024a0aa5baa6b9a8bbe Signed-off-by: Neale Ranns --- src/vnet/ip-neighbor/ip4_neighbor.c | 319 ++++++++++++++++++++++++++++++++++++ 1 file changed, 319 insertions(+) create mode 100644 src/vnet/ip-neighbor/ip4_neighbor.c (limited to 'src/vnet/ip-neighbor/ip4_neighbor.c') diff --git a/src/vnet/ip-neighbor/ip4_neighbor.c b/src/vnet/ip-neighbor/ip4_neighbor.c new file mode 100644 index 00000000000..2a9e2675a78 --- /dev/null +++ b/src/vnet/ip-neighbor/ip4_neighbor.c @@ -0,0 +1,319 @@ +/* + * Copyright (c) 2015 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. + */ +/* + * ip/ip4_forward.c: IP v4 forwarding + * + * Copyright (c) 2008 Eliot Dresselhaus + * + * 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 +#include + +void +ip4_neighbor_probe_dst (const ip_adjacency_t * adj, const ip4_address_t * dst) +{ + ip_interface_address_t *ia; + ip4_address_t *src; + + src = ip4_interface_address_matching_destination + (&ip4_main, + &adj->sub_type.nbr.next_hop.ip4, adj->rewrite_header.sw_if_index, &ia); + if (!src) + return; + + ip4_neighbor_probe (vlib_get_main (), vnet_get_main (), adj, src, dst); +} + +void +ip4_neighbor_advertise (vlib_main_t * vm, + vnet_main_t * vnm, + u32 sw_if_index, const ip4_address_t * addr) +{ + vnet_hw_interface_t *hi = vnet_get_sup_hw_interface (vnm, sw_if_index); + ip4_main_t *i4m = &ip4_main; + u8 *rewrite, rewrite_len; + + if (NULL == addr) + { + ip4_main_t *i4m = &ip4_main; + addr = ip4_interface_first_address (i4m, sw_if_index, 0); + } + + if (addr) + { + clib_warning ("Sending GARP for IP4 address %U on sw_if_idex %d", + format_ip4_address, addr, sw_if_index); + + /* Form GARP packet for output - Gratuitous ARP is an ARP request packet + where the interface IP/MAC pair is used for both source and request + MAC/IP pairs in the request */ + u32 bi = 0; + ethernet_arp_header_t *h = vlib_packet_template_get_packet + (vm, &i4m->ip4_arp_request_packet_template, &bi); + + if (!h) + return; + + mac_address_from_bytes (&h->ip4_over_ethernet[0].mac, hi->hw_address); + mac_address_from_bytes (&h->ip4_over_ethernet[1].mac, hi->hw_address); + h->ip4_over_ethernet[0].ip4 = addr[0]; + h->ip4_over_ethernet[1].ip4 = addr[0]; + + /* Setup MAC header with ARP Etype and broadcast DMAC */ + vlib_buffer_t *b = vlib_get_buffer (vm, bi); + rewrite = + ethernet_build_rewrite (vnm, sw_if_index, VNET_LINK_ARP, + VNET_REWRITE_FOR_SW_INTERFACE_ADDRESS_BROADCAST); + rewrite_len = vec_len (rewrite); + vlib_buffer_advance (b, -rewrite_len); + ethernet_header_t *e = vlib_buffer_get_current (b); + clib_memcpy_fast (e->dst_address, rewrite, rewrite_len); + vec_free (rewrite); + + /* Send GARP packet out the specified interface */ + vnet_buffer (b)->sw_if_index[VLIB_RX] = + vnet_buffer (b)->sw_if_index[VLIB_TX] = sw_if_index; + vlib_frame_t *f = vlib_get_frame_to_node (vm, hi->output_node_index); + u32 *to_next = vlib_frame_vector_args (f); + to_next[0] = bi; + f->n_vectors = 1; + vlib_put_frame_to_node (vm, hi->output_node_index, f); + } +} + +always_inline uword +ip4_arp_inline (vlib_main_t * vm, + vlib_node_runtime_t * node, + vlib_frame_t * frame, int is_glean) +{ + vnet_main_t *vnm = vnet_get_main (); + ip4_main_t *im = &ip4_main; + ip_lookup_main_t *lm = &im->lookup_main; + u32 *from, *to_next_drop; + uword n_left_from, n_left_to_next_drop, next_index; + u32 thread_index = vm->thread_index; + u64 seed; + + if (node->flags & VLIB_NODE_FLAG_TRACE) + ip4_forward_next_trace (vm, node, frame, VLIB_TX); + + seed = throttle_seed (&im->arp_throttle, thread_index, vlib_time_now (vm)); + + from = vlib_frame_vector_args (frame); + n_left_from = frame->n_vectors; + next_index = node->cached_next_index; + if (next_index == IP4_ARP_NEXT_DROP) + next_index = IP4_ARP_N_NEXT; /* point to first interface */ + + while (n_left_from > 0) + { + vlib_get_next_frame (vm, node, IP4_ARP_NEXT_DROP, + to_next_drop, n_left_to_next_drop); + + while (n_left_from > 0 && n_left_to_next_drop > 0) + { + u32 pi0, adj_index0, sw_if_index0; + ip4_address_t resolve0, src0; + vlib_buffer_t *p0, *b0; + ip_adjacency_t *adj0; + u64 r0; + + pi0 = from[0]; + p0 = vlib_get_buffer (vm, pi0); + + from += 1; + n_left_from -= 1; + to_next_drop[0] = pi0; + to_next_drop += 1; + n_left_to_next_drop -= 1; + + adj_index0 = vnet_buffer (p0)->ip.adj_index[VLIB_TX]; + adj0 = adj_get (adj_index0); + sw_if_index0 = adj0->rewrite_header.sw_if_index; + + if (is_glean) + { + /* resolve the packet's destination */ + ip4_header_t *ip0 = vlib_buffer_get_current (p0); + resolve0 = ip0->dst_address; + src0 = adj0->sub_type.glean.receive_addr.ip4; + } + else + { + /* resolve the incomplete adj */ + resolve0 = adj0->sub_type.nbr.next_hop.ip4; + /* Src IP address in ARP header. */ + if (ip4_src_address_for_packet (lm, sw_if_index0, &src0)) + { + /* No source address available */ + p0->error = node->errors[IP4_ARP_ERROR_NO_SOURCE_ADDRESS]; + continue; + } + } + + /* combine the address and interface for the hash key */ + r0 = (u64) resolve0.data_u32 << 32; + r0 |= sw_if_index0; + + if (throttle_check (&im->arp_throttle, thread_index, r0, seed)) + { + p0->error = node->errors[IP4_ARP_ERROR_THROTTLED]; + continue; + } + + /* + * the adj has been updated to a rewrite but the node the DPO that got + * us here hasn't - yet. no big deal. we'll drop while we wait. + */ + if (IP_LOOKUP_NEXT_REWRITE == adj0->lookup_next_index) + { + p0->error = node->errors[IP4_ARP_ERROR_RESOLVED]; + continue; + } + + /* + * Can happen if the control-plane is programming tables + * with traffic flowing; at least that's today's lame excuse. + */ + if ((is_glean && adj0->lookup_next_index != IP_LOOKUP_NEXT_GLEAN) + || (!is_glean && adj0->lookup_next_index != IP_LOOKUP_NEXT_ARP)) + { + p0->error = node->errors[IP4_ARP_ERROR_NON_ARP_ADJ]; + continue; + } + + /* Send ARP request. */ + b0 = ip4_neighbor_probe (vm, vnm, adj0, &src0, &resolve0); + + if (PREDICT_TRUE (NULL != b0)) + { + /* copy the persistent fields from the original */ + clib_memcpy_fast (b0->opaque2, p0->opaque2, + sizeof (p0->opaque2)); + p0->error = node->errors[IP4_ARP_ERROR_REQUEST_SENT]; + } + else + { + p0->error = node->errors[IP4_ARP_ERROR_NO_BUFFERS]; + continue; + } + } + + vlib_put_next_frame (vm, node, IP4_ARP_NEXT_DROP, n_left_to_next_drop); + } + + return frame->n_vectors; +} + +VLIB_NODE_FN (ip4_arp_node) (vlib_main_t * vm, vlib_node_runtime_t * node, + vlib_frame_t * frame) +{ + return (ip4_arp_inline (vm, node, frame, 0)); +} + +VLIB_NODE_FN (ip4_glean_node) (vlib_main_t * vm, vlib_node_runtime_t * node, + vlib_frame_t * frame) +{ + return (ip4_arp_inline (vm, node, frame, 1)); +} + +static char *ip4_arp_error_strings[] = { + [IP4_ARP_ERROR_THROTTLED] = "ARP requests throttled", + [IP4_ARP_ERROR_RESOLVED] = "ARP requests resolved", + [IP4_ARP_ERROR_NO_BUFFERS] = "ARP requests out of buffer", + [IP4_ARP_ERROR_REQUEST_SENT] = "ARP requests sent", + [IP4_ARP_ERROR_NON_ARP_ADJ] = "ARPs to non-ARP adjacencies", + [IP4_ARP_ERROR_NO_SOURCE_ADDRESS] = "no source address for ARP request", +}; + +/* *INDENT-OFF* */ +VLIB_REGISTER_NODE (ip4_arp_node) = +{ + .name = "ip4-arp", + .vector_size = sizeof (u32), + .format_trace = format_ip4_forward_next_trace, + .n_errors = ARRAY_LEN (ip4_arp_error_strings), + .error_strings = ip4_arp_error_strings, + .n_next_nodes = IP4_ARP_N_NEXT, + .next_nodes = { + [IP4_ARP_NEXT_DROP] = "ip4-drop", + }, +}; + +VLIB_REGISTER_NODE (ip4_glean_node) = +{ + .name = "ip4-glean", + .vector_size = sizeof (u32), + .format_trace = format_ip4_forward_next_trace, + .n_errors = ARRAY_LEN (ip4_arp_error_strings), + .error_strings = ip4_arp_error_strings, + .n_next_nodes = IP4_ARP_N_NEXT, + .next_nodes = { + [IP4_ARP_NEXT_DROP] = "ip4-drop", + }, +}; +/* *INDENT-ON* */ + +#define foreach_notrace_ip4_arp_error \ +_(THROTTLED) \ +_(RESOLVED) \ +_(NO_BUFFERS) \ +_(REQUEST_SENT) \ +_(NON_ARP_ADJ) \ +_(NO_SOURCE_ADDRESS) + +static clib_error_t * +arp_notrace_init (vlib_main_t * vm) +{ + vlib_node_runtime_t *rt = vlib_node_get_runtime (vm, ip4_arp_node.index); + + /* don't trace ARP request packets */ +#define _(a) \ + vnet_pcap_drop_trace_filter_add_del \ + (rt->errors[IP4_ARP_ERROR_##a], \ + 1 /* is_add */); + foreach_notrace_ip4_arp_error; +#undef _ + return 0; +} + +VLIB_INIT_FUNCTION (arp_notrace_init); + +/* + * fd.io coding-style-patch-verification: ON + * + * Local Variables: + * eval: (c-set-style "gnu") + * End: + */ -- cgit 1.2.3-korg