/* ** igmpproxy - IGMP proxy based multicast router ** Copyright (C) 2005 Johnny Egeland ** ** This program is free software; you can redistribute it and/or modify ** it under the terms of the GNU General Public License as published by ** the Free Software Foundation; either version 2 of the License, or ** (at your option) any later version. ** ** This program is distributed in the hope that it will be useful, ** but WITHOUT ANY WARRANTY; without even the implied warranty of ** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the ** GNU General Public License for more details. ** ** You should have received a copy of the GNU General Public License ** along with this program; if not, write to the Free Software ** Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA ** **---------------------------------------------------------------------------- ** ** This software is derived work from the following software. The original ** source code has been modified from it's original state by the author ** of igmpproxy. ** ** smcroute 0.92 - Copyright (C) 2001 Carsten Schill ** - Licensed under the GNU General Public License, version 2 ** ** mrouted 3.9-beta3 - COPYRIGHT 1989 by The Board of Trustees of ** Leland Stanford Junior University. ** - Original license can be found in the Stanford.txt file. ** */ /** * mroute-api.c * * This module contains the interface routines to the Linux mrouted API */ #include "igmpproxy.h" // MAX_MC_VIFS from mclab.h must have same value as MAXVIFS from mroute.h #if MAX_MC_VIFS != MAXVIFS # error "constants don't match, correct mclab.h" #endif // need an IGMP socket as interface for the mrouted API // - receives the IGMP messages int MRouterFD; /* socket for all network I/O */ char *recv_buf; /* input packet buffer */ char *send_buf; /* output packet buffer */ // my internal virtual interfaces descriptor vector static struct VifDesc { struct IfDesc *IfDp; } VifDescVc[ MAXVIFS ]; /* ** Initialises the mrouted API and locks it by this exclusively. ** ** returns: - 0 if the functions succeeds ** - the errno value for non-fatal failure condition */ int enableMRouter() { int Va = 1; if ( (MRouterFD = socket(AF_INET, SOCK_RAW, IPPROTO_IGMP)) < 0 ) my_log( LOG_ERR, errno, "IGMP socket open" ); if ( setsockopt( MRouterFD, IPPROTO_IP, MRT_INIT, (void *)&Va, sizeof( Va ) ) ) return errno; return 0; } /* ** Diables the mrouted API and relases by this the lock. ** */ void disableMRouter() { if ( setsockopt( MRouterFD, IPPROTO_IP, MRT_DONE, NULL, 0 ) || close( MRouterFD ) ) { MRouterFD = 0; my_log( LOG_ERR, errno, "MRT_DONE/close" ); } MRouterFD = 0; } /* ** Adds the interface '*IfDp' as virtual interface to the mrouted API ** */ void addVIF( struct IfDesc *IfDp ) { struct vifctl VifCtl; struct VifDesc *VifDp; /* search free VifDesc */ for ( VifDp = VifDescVc; VifDp < VCEP( VifDescVc ); VifDp++ ) { if ( ! VifDp->IfDp ) break; } /* no more space */ if ( VifDp >= VCEP( VifDescVc ) ) my_log( LOG_ERR, ENOMEM, "addVIF, out of VIF space" ); VifDp->IfDp = IfDp; VifCtl.vifc_vifi = VifDp - VifDescVc; VifCtl.vifc_flags = 0; /* no tunnel, no source routing, register ? */ VifCtl.vifc_threshold = VifDp->IfDp->threshold; // Packet TTL must be at least 1 to pass them VifCtl.vifc_rate_limit = VifDp->IfDp->ratelimit; // Ratelimit VifCtl.vifc_lcl_addr.s_addr = VifDp->IfDp->InAdr.s_addr; VifCtl.vifc_rmt_addr.s_addr = INADDR_ANY; // Set the index... VifDp->IfDp->index = VifCtl.vifc_vifi; my_log( LOG_NOTICE, 0, "adding VIF, Ix %d Fl 0x%x IP 0x%08x %s, Threshold: %d, Ratelimit: %d", VifCtl.vifc_vifi, VifCtl.vifc_flags, VifCtl.vifc_lcl_addr.s_addr, VifDp->IfDp->Name, VifCtl.vifc_threshold, VifCtl.vifc_rate_limit); struct SubnetList *currSubnet; for(currSubnet = IfDp->allowednets; currSubnet; currSubnet = currSubnet->next) { my_log(LOG_DEBUG, 0, " Network for [%s] : %s", IfDp->Name, inetFmts(currSubnet->subnet_addr, currSubnet->subnet_mask, s1)); } if ( setsockopt( MRouterFD, IPPROTO_IP, MRT_ADD_VIF, (char *)&VifCtl, sizeof( VifCtl ) ) ) my_log( LOG_ERR, errno, "MRT_ADD_VIF" ); } /* ** Adds the multicast routed '*Dp' to the kernel routes ** ** returns: - 0 if the function succeeds ** - the errno value for non-fatal failure condition */ int addMRoute( struct MRouteDesc *Dp ) { struct mfcctl CtlReq; int rc; CtlReq.mfcc_origin = Dp->OriginAdr; CtlReq.mfcc_mcastgrp = Dp->McAdr; CtlReq.mfcc_parent = Dp->InVif; /* copy the TTL vector */ memcpy( CtlReq.mfcc_ttls, Dp->TtlVc, sizeof( CtlReq.mfcc_ttls ) ); { char FmtBuO[ 32 ], FmtBuM[ 32 ]; my_log( LOG_NOTICE, 0, "Adding MFC: %s -> %s, InpVIf: %d", fmtInAdr( FmtBuO, CtlReq.mfcc_origin ), fmtInAdr( FmtBuM, CtlReq.mfcc_mcastgrp ), (int)CtlReq.mfcc_parent ); } rc = setsockopt( MRouterFD, IPPROTO_IP, MRT_ADD_MFC, (void *)&CtlReq, sizeof( CtlReq ) ); if (rc) my_log( LOG_WARNING, errno, "MRT_ADD_MFC" ); return rc; } /* ** Removes the multicast routed '*Dp' from the kernel routes ** ** returns: - 0 if the function succeeds ** - the errno value for non-fatal failure condition */ int delMRoute( struct MRouteDesc *Dp ) { struct mfcctl CtlReq; int rc; CtlReq.mfcc_origin = Dp->OriginAdr; CtlReq.mfcc_mcastgrp = Dp->McAdr; CtlReq.mfcc_parent = Dp->InVif; /* clear the TTL vector */ memset( CtlReq.mfcc_ttls, 0, sizeof( CtlReq.mfcc_ttls ) ); { char FmtBuO[ 32 ], FmtBuM[ 32 ]; my_log( LOG_NOTICE, 0, "Removing MFC: %s -> %s, InpVIf: %d", fmtInAdr( FmtBuO, CtlReq.mfcc_origin ), fmtInAdr( FmtBuM, CtlReq.mfcc_mcastgrp ), (int)CtlReq.mfcc_parent ); } rc = setsockopt( MRouterFD, IPPROTO_IP, MRT_DEL_MFC, (void *)&CtlReq, sizeof( CtlReq ) ); if (rc) my_log( LOG_WARNING, errno, "MRT_DEL_MFC" ); return rc; } /* ** Returns for the virtual interface index for '*IfDp' ** ** returns: - the vitrual interface index if the interface is registered ** - -1 if no virtual interface exists for the interface ** */ int getVifIx( struct IfDesc *IfDp ) { struct VifDesc *Dp; for ( Dp = VifDescVc; Dp < VCEP( VifDescVc ); Dp++ ) if ( Dp->IfDp == IfDp ) return Dp - VifDescVc; return -1; }