/**************************************************************************** * net/igmp/igmp_send.c * * Copyright (C) 2010, 2015 Gregory Nutt. All rights reserved. * Author: Gregory Nutt * * 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. Neither the name NuttX nor the names of its contributors may be * used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS * "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 * COPYRIGHT OWNER OR CONTRIBUTORS 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 #include #include "devif/devif.h" #include "inet/inet.h" #include "igmp/igmp.h" #ifdef CONFIG_NET_IGMP /**************************************************************************** * Pre-processor Definitions ****************************************************************************/ /* Debug */ #undef IGMP_DUMPPKT /* Define to enable packet dump */ #ifndef CONFIG_DEBUG_NET # undef IGMP_DUMPPKT #endif #ifdef IGMP_DUMPPKT # define igmp_dumppkt(b,n) lib_dumpbuffer("IGMP", (FAR const uint8_t*)(b), (n)) #else # define igmp_dumppkt(b,n) #endif /* Buffer layout */ #define RASIZE (4) #define IPv4BUF ((FAR struct igmp_iphdr_s *)&dev->d_buf[NET_LL_HDRLEN(dev)]) #define IGMPBUF(hl) ((FAR struct igmp_hdr_s *)&dev->d_buf[NET_LL_HDRLEN(dev) + (hl)]) /**************************************************************************** * Private Functions ****************************************************************************/ static uint16_t igmp_chksum(FAR uint8_t *buffer, int buflen) { uint16_t sum = net_chksum((FAR uint16_t *)buffer, buflen); return sum ? sum : 0xffff; } /**************************************************************************** * Public Functions ****************************************************************************/ /**************************************************************************** * Name: igmp_send * * Description: * Sends an IGMP IP packet on a network interface. This function constructs * the IP header and calculates the IP header checksum. * * Input Parameters: * dev - The device driver structure to use in the send operation. * group - Describes the multicast group member and identifies the * message to be sent. * destipaddr - The IP address of the recipient of the message * msgid - ID of message to send * * Returned Value: * None * * Assumptions: * The network is locked. * ****************************************************************************/ void igmp_send(FAR struct net_driver_s *dev, FAR struct igmp_group_s *group, FAR in_addr_t *destipaddr, uint8_t msgid) { FAR struct igmp_iphdr_s *ipv4 = IPv4BUF; FAR struct igmp_hdr_s *igmp; uint16_t iphdrlen; ninfo("msgid: %02x destipaddr: %08x\n", msgid, (int)*destipaddr); /* The IGMP header immediately follows the IP header */ iphdrlen = IPv4_HDRLEN + RASIZE; igmp = IGMPBUF(iphdrlen); /* The total length to send is the size of the IP and IGMP headers and 4 * bytes for the ROUTER ALERT (and, eventually, the Ethernet header) */ dev->d_len = iphdrlen + IGMP_HDRLEN; /* The total size of the data is the size of the IGMP header */ dev->d_sndlen = IGMP_HDRLEN; /* Add the router alert option to the IPv4 header (RFC 2113) */ ipv4->ra[0] = HTONS(IPOPT_RA >> 16); ipv4->ra[1] = HTONS(IPOPT_RA & 0xffff); /* Initialize the IPv4 header */ ipv4->vhl = 0x46; /* 4->IP; 6->24 bytes */ ipv4->tos = 0; ipv4->len[0] = (dev->d_len >> 8); ipv4->len[1] = (dev->d_len & 0xff); ++g_ipid; ipv4->ipid[0] = g_ipid >> 8; ipv4->ipid[1] = g_ipid & 0xff; ipv4->ipoffset[0] = IP_FLAG_DONTFRAG >> 8; ipv4->ipoffset[1] = IP_FLAG_DONTFRAG & 0xff; ipv4->ttl = IGMP_TTL; ipv4->proto = IP_PROTO_IGMP; net_ipv4addr_hdrcopy(ipv4->srcipaddr, &dev->d_ipaddr); net_ipv4addr_hdrcopy(ipv4->destipaddr, destipaddr); /* Calculate IP checksum. */ ipv4->ipchksum = 0; ipv4->ipchksum = ~igmp_chksum((FAR uint8_t *)igmp, iphdrlen); /* Set up the IGMP message */ igmp->type = msgid; igmp->maxresp = 0; net_ipv4addr_hdrcopy(igmp->grpaddr, &group->grpaddr); /* Calculate the IGMP checksum. */ igmp->chksum = 0; igmp->chksum = ~igmp_chksum(&igmp->type, IGMP_HDRLEN); IGMP_STATINCR(g_netstats.igmp.poll_send); IGMP_STATINCR(g_netstats.ipv4.sent); ninfo("Outgoing IGMP packet length: %d (%d)\n", dev->d_len, (ipv4->len[0] << 8) | ipv4->len[1]); igmp_dumppkt(RA, iphdrlen + IGMP_HDRLEN); } #endif /* CONFIG_NET_IGMP */