/**************************************************************************** * net/icmpv6/icmpv6_input.c * Handling incoming ICMPv6 input * * Copyright (C) 2015, 2017-2018 Gregory Nutt. All rights reserved. * Author: Gregory Nutt * * Adapted for NuttX from logic in uIP which also has a BSD-like license: * * Original author Adam Dunkels * Copyright () 2001-2003, Adam Dunkels. * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. The name of the author may not be used to endorse or promote * products derived from this software without specific prior * written permission. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE * GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. * ****************************************************************************/ /**************************************************************************** * Included Files ****************************************************************************/ #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 IPv6BUF ((FAR struct ipv6_hdr_s *)&dev->d_buf[NET_LL_HDRLEN(dev)]) #define ICMPv6BUF ((FAR struct icmpv6_hdr_s *) \ (&dev->d_buf[NET_LL_HDRLEN(dev)] + iplen)) #define ICMPv6REPLY ((FAR struct icmpv6_echo_reply_s *)icmpv6) #define ICMPv6SIZE ((dev)->d_len - iplen) #define ICMPv6SOLICIT ((struct icmpv6_neighbor_solicit_s *)icmpv6) #define ICMPv6ADVERTISE ((struct icmpv6_neighbor_advertise_s *)icmpv6) #define ICMPv6RADVERTISE ((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) /**************************************************************************** * Private Functions ****************************************************************************/ /**************************************************************************** * 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. * ****************************************************************************/ #ifdef CONFIG_NET_ICMPv6_SOCKET 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; FAR struct icmpv6_hdr_s *icmpv6; FAR struct iob_s *iob; struct sockaddr_in6 inaddr; uint16_t offset; uint16_t buflen; uint8_t addrsize; int ret; /* Try to allocate on I/O buffer to start the chain without waiting (and * throttling as necessary). If we would have to wait, then drop the * packet. */ iob = iob_tryalloc(true, IOBUSER_NET_SOCK_ICMPv6); if (iob == NULL) { nerr("ERROR: Failed to create new I/O buffer chain\n"); goto drop; } /* 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 I/O buffer chain. We will not wait * for an I/O buffer to become available in this context. It there is * any failure to allocated, the entire I/O buffer chain will be discarded. */ addrsize = sizeof(struct sockaddr_in6); ret = iob_trycopyin(iob, &addrsize, sizeof(uint8_t), 0, true, IOBUSER_NET_SOCK_ICMPv6); if (ret < 0) { /* On a failure, iob_trycopyin return a negated error value but does * not free any I/O buffers. */ nerr("ERROR: Failed to length to the I/O buffer chain: %d\n", ret); goto drop_with_chain; } offset = sizeof(uint8_t); ret = iob_trycopyin(iob, (FAR const uint8_t *)&inaddr, sizeof(struct sockaddr_in6), offset, true, IOBUSER_NET_SOCK_ICMPv6); if (ret < 0) { /* On a failure, iob_trycopyin return a negated error value but does * not free any I/O buffers. */ nerr("ERROR: Failed to source address to the I/O buffer chain: %d\n", ret); goto drop_with_chain; } offset += sizeof(struct sockaddr_in6); /* Copy the new ICMPv6 reply into the I/O buffer chain (without waiting) */ buflen = ICMPv6SIZE; icmpv6 = ICMPv6BUF; ret = iob_trycopyin(iob, (FAR uint8_t *)ICMPv6REPLY, buflen, offset, true, IOBUSER_NET_SOCK_ICMPv6); if (ret < 0) { /* On a failure, iob_copyin return a negated error value but does * not free any I/O buffers. */ nerr("ERROR: Failed to add data to the I/O buffer chain: %d\n", ret); goto drop_with_chain; } /* 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); goto drop_with_chain; } ninfo("Buffered %d bytes\n", buflen + addrsize + 1); dev->d_len = 0; return buflen; drop_with_chain: iob_free_chain(iob, IOBUSER_NET_SOCK_ICMPv6); drop: dev->d_len = 0; return 0; } #endif /**************************************************************************** * 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 = ICMPv6BUF; #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 + sizeof(struct icmpv6_prefixinfo_s) <= optlen; ) { FAR struct icmpv6_srclladdr_s *sllopt = (FAR struct icmpv6_srclladdr_s *)&options[ndx]; if (sllopt->opttype == ICMPv6_OPT_SRCLLADDR) { neighbor_add(dev, ipv6->srcipaddr, sllopt->srclladdr); } FAR struct icmpv6_prefixinfo_s *opt = (FAR struct icmpv6_prefixinfo_s *)&options[ndx]; /* Is this the sought for prefix? Is it the correct size? Is * the "A" flag set? */ if (opt->opttype == ICMPv6_OPT_PREFIX && (opt->flags & ICMPv6_PRFX_FLAG_A) != 0) { /* Yes.. Notify any waiting threads */ icmpv6_rnotify(dev, ipv6->srcipaddr, opt->prefix, opt->preflen); prefix = true; } /* 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; #ifdef CONFIG_NET_ICMPv6_SOCKET /* If an ICMPv6 echo reply is received then there should also be * a thread waiting to received the echo response. */ case ICMPv6_ECHO_REPLY: { FAR struct icmpv6_echo_reply_s *reply; FAR struct icmpv6_conn_s *conn; uint16_t flags = ICMPv6_NEWDATA; /* Nothing consumed the ICMP reply. That might be because this is * an old, invalid reply or simply because the ping application * has not yet put its poll or recv in place. */ /* Is there any connection that might expect this reply? */ reply = ICMPv6REPLY; conn = icmpv6_findconn(dev, reply->id); if (conn == NULL) { /* No.. drop the packet */ goto icmpv6_drop_packet; } /* Dispatch the ECHO reply to the waiting thread */ flags = devif_conn_event(dev, conn, flags, conn->list); /* Was the ECHO reply consumed by any waiting thread? */ if ((flags & ICMPv6_NEWDATA) != 0) { uint16_t nbuffered; /* Yes.. Add the ICMP echo reply to the IPPROTO_ICMP socket read * ahead buffer. */ nbuffered = icmpv6_datahandler(dev, conn, iplen); if (nbuffered == 0) { /* Could not buffer the data.. drop the packet */ goto icmpv6_drop_packet; } } goto icmpv6_send_nothing; } break; #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: { 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 */