/**************************************************************************** * net/icmpv6/icmpv6_input.c * Handling incoming ICMPv6 input * * Licensed to the Apache Software Foundation (ASF) under one or more * contributor license agreements. See the NOTICE file distributed with * this work for additional information regarding copyright ownership. The * ASF licenses this file to you 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. * ****************************************************************************/ /**************************************************************************** * Included Files ****************************************************************************/ #include #include #include #include #include #include #include #include #include #include "devif/devif.h" #include "neighbor/neighbor.h" #include "utils/utils.h" #include "icmpv6/icmpv6.h" #include "mld/mld.h" #ifdef CONFIG_NET_ICMPv6 /**************************************************************************** * Pre-processor Definitions ****************************************************************************/ #define ICMPv6REPLY ((FAR struct icmpv6_echo_reply_s *)icmpv6) #define ICMPv6SIZE ((dev)->d_len - iplen) #define ICMPv6SOLICIT ((FAR struct icmpv6_neighbor_solicit_s *)icmpv6) #define ICMPv6ADVERTISE ((FAR struct icmpv6_neighbor_advertise_s *)icmpv6) #define ICMPv6RADVERTISE ((FAR struct icmpv6_router_advertise_s *)icmpv6) #define MLDQUERY ((FAR struct mld_mcast_listen_query_s *)icmpv6) #define MLDREPORT_V1 ((FAR struct mld_mcast_listen_report_v1_s *)icmpv6) #define MLDREPORT_V2 ((FAR struct mld_mcast_listen_report_v2_s *)icmpv6) #define MLDDONE ((FAR struct mld_mcast_listen_done_s *)icmpv6) #ifdef CONFIG_NET_ICMPv6_SOCKET /**************************************************************************** * Private Types ****************************************************************************/ struct icmpv6_deliver_s { FAR struct net_driver_s *dev; /* Current network device */ unsigned int iplen; /* The size of the IPv6 header */ bool delivered; /* Whether the message is delivered */ }; /**************************************************************************** * Private Functions ****************************************************************************/ static bool icmpv6_filter(FAR const uint32_t *data, uint8_t type) { /* We require only the four bytes of the ICMPv6 header. */ DEBUGASSERT(data != NULL); return (data[type >> 5] & (1u << (type & 31))) != 0; } /**************************************************************************** * Name: icmpv6_datahandler * * Description: * Handle ICMPv6 echo replies that are not accepted by the application. * * Input Parameters: * dev - Device instance only the input packet in d_buf, length = d_len; * conn - A pointer to the ICMPv6 connection structure * buffer - A pointer to the buffer to be copied to the read-ahead * buffers * buflen - The number of bytes to copy to the read-ahead buffer. * * Returned Value: * The number of bytes actually buffered is returned. This will be either * zero or equal to buflen; partial packets are not buffered. * ****************************************************************************/ static uint16_t icmpv6_datahandler(FAR struct net_driver_s *dev, FAR struct icmpv6_conn_s *conn, unsigned int iplen) { FAR struct ipv6_hdr_s *ipv6; struct sockaddr_in6 inaddr; FAR struct iob_s *iob; unsigned int offset; uint16_t buflen; int ret; iob = iob_tryalloc(false); if (iob == NULL) { return -ENOMEM; } /* Put the IPv6 address at the beginning of the read-ahead buffer */ ipv6 = IPv6BUF; inaddr.sin6_family = AF_INET6; inaddr.sin6_port = 0; net_ipv6addr_copy(inaddr.sin6_addr.s6_addr16, ipv6->srcipaddr); /* Copy the src address info into the front of I/O buffer chain which * overwrites the contents of the packet header field. */ memcpy(iob->io_data, &inaddr, sizeof(struct sockaddr_in6)); offset = sizeof(struct sockaddr_in6); iob->io_data[offset++] = ipv6->ttl; iob_reserve(iob, offset); /* Copy the ICMPv6 message into the I/O buffer chain (without waiting) */ ret = iob_clone_partial(dev->d_iob, dev->d_iob->io_pktlen, iplen, iob, 0, true, false); if (ret < 0) { iob_free_chain(iob); return ret; } buflen = ICMPv6SIZE; /* Add the new I/O buffer chain to the tail of the read-ahead queue (again * without waiting). */ ret = iob_tryadd_queue(iob, &conn->readahead); if (ret < 0) { nerr("ERROR: Failed to queue the I/O buffer chain: %d\n", ret); iob_free_chain(iob); } else { ninfo("Buffered %d bytes\n", buflen); } return buflen; } /**************************************************************************** * Name: icmpv6_delivery_callback * * Description: * Copy the icmpv6 package to the application according to the filter * conditions, but ICMPv6_ECHO_REPLY is a special message type, if there * is an application waiting, it will also copy. * * Input Parameters: * conn - A pointer to the ICMPv6 connection structure. * arg - The context information * ****************************************************************************/ static int icmpv6_delivery_callback(FAR struct icmpv6_conn_s *conn, FAR void *arg) { FAR struct icmpv6_deliver_s *info = arg; FAR struct net_driver_s *dev = info->dev; FAR struct icmpv6_hdr_s *icmpv6 = IPBUF(info->iplen); if (icmpv6_filter(conn->filter.icmp6_filt, icmpv6->type) && (icmpv6->type != ICMPv6_ECHO_REPLY || conn->id != ICMPv6REPLY->id || conn->dev != dev)) { return 0; } info->delivered = true; if (devif_conn_event(dev, ICMPv6_NEWDATA, conn->sconn.list) != ICMPv6_NEWDATA) { dev->d_len = dev->d_iob->io_pktlen; } else { icmpv6_datahandler(dev, conn, info->iplen); } return 0; } /**************************************************************************** * Name: icmpv6_deliver * * Description: * Copy the icmpv6 package to the application according to the filter * conditions, but ICMPv6_ECHO_REPLY is a special message type, if there * is an application waiting, it will also copy. * * Input Parameters: * dev - Reference to a device driver structure. * iplen - The size of the IPv6 header. This may be larger than * IPv6_HDRLEN the IPv6 header if IPv6 extension headers are * present. * ****************************************************************************/ static bool icmpv6_deliver(FAR struct net_driver_s *dev, unsigned int iplen) { struct icmpv6_deliver_s info; info.dev = dev; info.iplen = iplen; info.delivered = false; icmpv6_foreach(icmpv6_delivery_callback, &info); return info.delivered; } #endif /* CONFIG_NET_ICMPv6_SOCKET */ /**************************************************************************** * Public Functions ****************************************************************************/ /**************************************************************************** * Name: icmpv6_input * * Description: * Handle incoming ICMPv6 input * * Input Parameters: * dev - The device driver structure containing the received ICMPv6 * packet * iplen - The size of the IPv6 header. This may be larger than * IPv6_HDRLEN the IPv6 header if IPv6 extension headers are * present. * * Returned Value: * None * * Assumptions: * The network is locked. * ****************************************************************************/ void icmpv6_input(FAR struct net_driver_s *dev, unsigned int iplen) { FAR struct ipv6_hdr_s *ipv6 = IPv6BUF; FAR struct icmpv6_hdr_s *icmpv6 = IPBUF(iplen); #ifdef CONFIG_NET_ICMPv6_SOCKET bool delivered = icmpv6_deliver(dev, iplen); #endif #ifdef CONFIG_NET_STATISTICS g_netstats.icmpv6.recv++; #endif /* REVISIT: * - Verify that the message length is valid. * - Verify the ICMPv6 checksum */ /* Handle the ICMPv6 message by its type */ switch (icmpv6->type) { /* If we get a neighbor solicitation for our address we should send * a neighbor advertisement message back. */ case ICMPv6_NEIGHBOR_SOLICIT: { FAR struct icmpv6_neighbor_solicit_s *sol; /* Check if we are the target of the solicitation */ sol = ICMPv6SOLICIT; if (net_ipv6addr_cmp(sol->tgtaddr, dev->d_ipv6addr)) { if (sol->opttype == ICMPv6_OPT_SRCLLADDR) { /* Save the sender's address mapping in our Neighbor Table. */ neighbor_add(dev, ipv6->srcipaddr, sol->srclladdr); } /* Yes.. Send a neighbor advertisement back to where the neighbor * solicitation came from. */ icmpv6_advertise(dev, ipv6->srcipaddr); /* All statistics have been updated. Nothing to do but exit. */ return; } else { goto icmpv6_drop_packet; } } break; /* Check if we received a Neighbor Advertisement */ case ICMPv6_NEIGHBOR_ADVERTISE: { FAR struct icmpv6_neighbor_advertise_s *adv; /* If the IPv6 destination address matches our address, and if so, * add the neighbor address mapping to the list of neighbors. * * Missing checks: * optlen = 1 (8 octets) * Should only update Neighbor Table if * [O]verride bit is set in flags */ adv = ICMPv6ADVERTISE; if (net_ipv6addr_cmp(ipv6->destipaddr, dev->d_ipv6addr)) { /* This message is required to support the Target link-layer * address option. */ if (adv->opttype == ICMPv6_OPT_TGTLLADDR) { /* Save the sender's address mapping in our Neighbor Table. */ neighbor_add(dev, ipv6->srcipaddr, adv->tgtlladdr); } #ifdef CONFIG_NET_ICMPv6_NEIGHBOR /* Then notify any logic waiting for the Neighbor Advertisement */ icmpv6_notify(ipv6->srcipaddr); #endif /* We consumed the packet but we don't send anything in * response. */ goto icmpv6_send_nothing; } goto icmpv6_drop_packet; } break; #ifdef CONFIG_NET_ICMPv6_ROUTER /* Check if we received a Router Solicitation */ case ICMPV6_ROUTER_SOLICIT: { /* Just give a knee-jerk Router Advertisement in respond with no * further examination of the Router Solicitation. */ icmpv6_radvertise(dev); /* All statistics have been updated. Nothing to do but exit. */ return; } #endif #ifdef CONFIG_NET_ICMPv6_AUTOCONF /* Check if we received a Router Advertisement */ case ICMPV6_ROUTER_ADVERTISE: { FAR struct icmpv6_router_advertise_s *adv; FAR uint8_t *options; bool prefix = false; uint16_t pktlen; uint16_t optlen; int ndx; /* Get the length of the option data */ pktlen = (uint16_t)ipv6->len[0] << 8 | ipv6->len[1]; if (pktlen <= ICMPv6_RADV_MINLEN) { /* Too small to contain any options */ goto icmpv6_drop_packet; } optlen = ICMPv6_RADV_OPTLEN(pktlen); /* We need to have a valid router advertisement with a Prefix and * with the "A" bit set in the flags. Options immediately follow * the ICMPv6 router advertisement. */ adv = ICMPv6RADVERTISE; options = (FAR uint8_t *)adv + sizeof(struct icmpv6_router_advertise_s); for (ndx = 0; ndx < optlen; ) { FAR struct icmpv6_generic_s *opt = (FAR struct icmpv6_generic_s *)&options[ndx]; switch (opt->opttype) { case ICMPv6_OPT_SRCLLADDR: { FAR struct icmpv6_srclladdr_s *sllopt = (FAR struct icmpv6_srclladdr_s *)opt; neighbor_add(dev, ipv6->srcipaddr, sllopt->srclladdr); } break; case ICMPv6_OPT_PREFIX: { FAR struct icmpv6_prefixinfo_s *prefixopt = (FAR struct icmpv6_prefixinfo_s *)opt; /* Is the "A" flag set? */ if ((prefixopt->flags & ICMPv6_PRFX_FLAG_A) != 0) { /* Yes.. Set the new network addresses. */ icmpv6_setaddresses(dev, ipv6->srcipaddr, prefixopt->prefix, prefixopt->preflen); /* Notify any waiting threads */ icmpv6_rnotify(dev); prefix = true; } } break; case ICMPv6_OPT_MTU: { FAR struct icmpv6_mtu_s *mtuopt = (FAR struct icmpv6_mtu_s *)opt; dev->d_pktsize = NTOHS(mtuopt->mtu[1]) + dev->d_llhdrlen; } break; #ifdef CONFIG_ICMPv6_AUTOCONF_RDNSS case ICMPv6_OPT_RDNSS: { FAR struct icmpv6_rdnss_s *rdnss = (FAR struct icmpv6_rdnss_s *)opt; FAR struct in6_addr *servers; struct sockaddr_in6 addr; int nservers; int ret; int i; if (rdnss->optlen < 3) { nerr("rdnss error length %d\n", rdnss->optlen); break; } /* optlen is in units of 8 bytes. The header is 1 unit * (8 bytes) and each address is another 2 units * (16 bytes). So the number of addresses is equal to * (optlen - 1) / 2. */ servers = (FAR struct in6_addr *)rdnss->servers; nservers = (rdnss->optlen - 1) / 2; /* Set the IPv6 DNS server address */ memset(&addr, 0, sizeof(addr)); addr.sin6_family = AF_INET6; for (i = 0; i < CONFIG_NETDB_DNSSERVER_NAMESERVERS && i < nservers; i++) { net_ipv6addr_copy(&addr.sin6_addr, servers + i); ret = dns_add_nameserver( (FAR const struct sockaddr *)&addr, sizeof(struct sockaddr_in6)); if (ret < 0 && ret != -EEXIST) { nerr("dns add nameserver failed %d", ret); } } } break; #endif default: break; } /* Skip to the next option (units of octets) */ ndx += (opt->optlen << 3); } if (prefix) { goto icmpv6_send_nothing; } goto icmpv6_drop_packet; } break; #endif /* Handle the ICMPv6 Echo Request */ case ICMPv6_ECHO_REQUEST: { /* ICMPv6 echo (i.e., ping) processing. This is simple, we only * change the ICMPv6 type from ECHO to ECHO_REPLY and update the * ICMPv6 checksum before we return the packet. */ icmpv6->type = ICMPv6_ECHO_REPLY; net_ipv6addr_copy(ipv6->destipaddr, ipv6->srcipaddr); net_ipv6addr_copy(ipv6->srcipaddr, dev->d_ipv6addr); icmpv6->chksum = 0; icmpv6->chksum = ~icmpv6_chksum(dev, iplen); } break; #if (CONFIG_NET_ICMPv6_PMTU_ENTRIES > 0) case ICMPv6_PACKET_TOO_BIG: { FAR struct icmpv6_pmtu_entry *entry; FAR struct ipv6_hdr_s *inner; int mtu; mtu = (ntohs(icmpv6->data[0]) << 16) | (ntohs(icmpv6->data[1])); if (mtu <= 0) { goto icmpv6_type_error; } inner = (FAR struct ipv6_hdr_s *)(icmpv6 + 1); entry = icmpv6_find_pmtu_entry(inner->destipaddr); if (entry == NULL) { icmpv6_add_pmtu_entry(inner->destipaddr, mtu); } else { entry->pmtu = mtu; } goto icmpv6_send_nothing; } #endif #ifdef CONFIG_NET_MLD /* Dispatch received Multicast Listener Discovery (MLD) packets. */ case ICMPV6_MCAST_LISTEN_QUERY: /* Multicast Listener Query, RFC 2710 and RFC 3810 */ { FAR struct mld_mcast_listen_query_s *query = MLDQUERY; int ret; ret = mld_query(dev, query); if (ret < 0) { goto icmpv6_drop_packet; } } break; case ICMPV6_MCAST_LISTEN_REPORT_V1: /* Version 1 Multicast Listener Report, RFC 2710 */ { FAR struct mld_mcast_listen_report_v1_s *report = MLDREPORT_V1; int ret; ret = mld_report_v1(dev, report); if (ret < 0) { goto icmpv6_drop_packet; } } break; case ICMPV6_MCAST_LISTEN_REPORT_V2: /* Version 2 Multicast Listener Report, RFC 3810 */ { FAR struct mld_mcast_listen_report_v2_s *report = MLDREPORT_V2; int ret; ret = mld_report_v2(dev, report); if (ret < 0) { goto icmpv6_drop_packet; } } break; case ICMPV6_MCAST_LISTEN_DONE: /* Multicast Listener Done, RFC 2710 */ { FAR struct mld_mcast_listen_done_s *done = MLDDONE; int ret; ret = mld_done(dev, done); if (ret < 0) { goto icmpv6_drop_packet; } } break; #endif default: { #ifdef CONFIG_NET_ICMPv6_SOCKET if (delivered) { goto icmpv6_send_nothing; } #endif nwarn("WARNING: Unknown ICMPv6 type: %d\n", icmpv6->type); goto icmpv6_type_error; } } #ifdef CONFIG_NET_STATISTICS if (dev->d_len > 0) { ninfo("Outgoing ICMPv6 packet length: %d (%d)\n", dev->d_len, (ipv6->len[0] << 8) | ipv6->len[1]); g_netstats.icmpv6.sent++; g_netstats.ipv6.sent++; } #endif return; icmpv6_type_error: #ifdef CONFIG_NET_STATISTICS g_netstats.icmpv6.typeerr++; #endif icmpv6_drop_packet: #ifdef CONFIG_NET_STATISTICS g_netstats.icmpv6.drop++; #endif icmpv6_send_nothing: dev->d_len = 0; } #endif /* CONFIG_NET_ICMPv6 */