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Files
2016-11-30 09:03:17 +08:00

261 lines
8.4 KiB
C
Executable File

/*
** igmpproxy - IGMP proxy based multicast router
** Copyright (C) 2005 Johnny Egeland <johnny@rlo.org>
**
** 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 <carsten@cschill.de>
** - 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 "doc/mrouted-LINCESE" file.
**
*/
#include "defs.h"
#include <linux/sockios.h>
struct IfDesc IfDescVc[ MAX_IF ], *IfDescEp = IfDescVc;
/*
** Builds up a vector with the interface of the machine. Calls to the other functions of
** the module will fail if they are called before the vector is build.
**
*/
void buildIfVc() {
struct ifreq IfVc[ sizeof( IfDescVc ) / sizeof( IfDescVc[ 0 ] ) ];
struct ifreq *IfEp;
int Sock;
if ( (Sock = socket( AF_INET, SOCK_DGRAM, 0 )) < 0 )
log( LOG_ERR, errno, "RAW socket open" );
/* get If vector
*/
{
struct ifconf IoCtlReq;
IoCtlReq.ifc_buf = (void *)IfVc;
IoCtlReq.ifc_len = sizeof( IfVc );
if ( ioctl( Sock, SIOCGIFCONF, &IoCtlReq ) < 0 )
log( LOG_ERR, errno, "ioctl SIOCGIFCONF" );
IfEp = (void *)((char *)IfVc + IoCtlReq.ifc_len);
}
/* loop over interfaces and copy interface info to IfDescVc
*/
{
struct ifreq *IfPt;
struct IfDesc *IfDp;
// Temp keepers of interface params...
uint32 addr, subnet, mask;
for ( IfPt = IfVc; IfPt < IfEp; IfPt++ ) {
struct ifreq IfReq;
char FmtBu[ 32 ];
strncpy( IfDescEp->Name, IfPt->ifr_name, sizeof( IfDescEp->Name ) );
// Currently don't set any allowed nets...
//IfDescEp->allowednets = NULL;
// Set the index to -1 by default.
IfDescEp->index = -1;
/* don't retrieve more info for non-IP interfaces
*/
if ( IfPt->ifr_addr.sa_family != AF_INET ) {
IfDescEp->InAdr.s_addr = 0; /* mark as non-IP interface */
IfDescEp++;
continue;
}
// Get the interface adress...
IfDescEp->InAdr = ((struct sockaddr_in *)&IfPt->ifr_addr)->sin_addr;
addr = IfDescEp->InAdr.s_addr;
memcpy( IfReq.ifr_name, IfDescEp->Name, sizeof( IfReq.ifr_name ) );
// Get the subnet mask...
if (ioctl(Sock, SIOCGIFNETMASK, &IfReq ) < 0)
log(LOG_ERR, errno, "ioctl SIOCGIFNETMASK for %s", IfReq.ifr_name);
mask = ((struct sockaddr_in *)&IfReq.ifr_addr)->sin_addr.s_addr;
subnet = addr & mask;
// Get the physical index of the Interface
if (ioctl(Sock, SIOCGIFINDEX, &IfReq ) < 0)
log(LOG_ERR, errno, "ioctl SIOCGIFINDEX for %s", IfReq.ifr_name);
log(LOG_DEBUG, 0, "Physical Index value of IF '%s' is %d",
IfDescEp->Name, IfReq.ifr_ifindex);
/* get if flags
**
** typical flags:
** lo 0x0049 -> Running, Loopback, Up
** ethx 0x1043 -> Multicast, Running, Broadcast, Up
** ipppx 0x0091 -> NoArp, PointToPoint, Up
** grex 0x00C1 -> NoArp, Running, Up
** ipipx 0x00C1 -> NoArp, Running, Up
*/
if ( ioctl( Sock, SIOCGIFFLAGS, &IfReq ) < 0 )
log( LOG_ERR, errno, "ioctl SIOCGIFFLAGS" );
IfDescEp->Flags = IfReq.ifr_flags;
// Insert the verified subnet as an allowed net...
IfDescEp->allowednets = (struct SubnetList *)malloc(sizeof(struct SubnetList));
if(IfDescEp->allowednets == NULL) log(LOG_ERR, 0, "Out of memory !");
// Create the network address for the IF..
IfDescEp->allowednets->next = NULL;
IfDescEp->allowednets->subnet_mask = mask;
IfDescEp->allowednets->subnet_addr = subnet;
// Set the default params for the IF...
IfDescEp->state = /*IF_STATE_DOWNSTREAM*/IF_STATE_DISABLED;
IfDescEp->robustness = DEFAULT_ROBUSTNESS;
IfDescEp->threshold = DEFAULT_THRESHOLD; /* ttl limit */
IfDescEp->ratelimit = DEFAULT_RATELIMIT;
// Debug log the result...
IF_DEBUG log( LOG_DEBUG, 0, "buildIfVc: Interface %s Addr: %s, Flags: 0x%04x, Network: %s",
IfDescEp->Name,
fmtInAdr( FmtBu, IfDescEp->InAdr ),
IfDescEp->Flags,
inetFmts(subnet,mask, s1));
IfDescEp++;
}
}
close( Sock );
}
/*
** Returns a pointer to the IfDesc of the interface 'IfName'
**
** returns: - pointer to the IfDesc of the requested interface
** - NULL if no interface 'IfName' exists
**
*/
struct IfDesc *getIfByName( const char *IfName ) {
struct IfDesc *Dp;
for ( Dp = IfDescVc; Dp < IfDescEp; Dp++ )
if ( ! strcmp( IfName, Dp->Name ) )
return Dp;
return NULL;
}
/*
** Returns a pointer to the IfDesc of the interface 'Ix'
**
** returns: - pointer to the IfDesc of the requested interface
** - NULL if no interface 'Ix' exists
**
*/
struct IfDesc *getIfByIx( unsigned Ix ) {
struct IfDesc *Dp = &IfDescVc[ Ix ];
return Dp < IfDescEp ? Dp : NULL;
}
/**
* Returns a pointer to the IfDesc whose subnet matches
* the supplied IP adress. The IP must match a interfaces
* subnet, or any configured allowed subnet on a interface.
*/
struct IfDesc *getIfByAddress( uint32 ipaddr ) {
struct IfDesc *Dp;
struct SubnetList *currsubnet;
for ( Dp = IfDescVc; Dp < IfDescEp; Dp++ ) {
// Loop through all registered allowed nets of the VIF...
for(currsubnet = Dp->allowednets; currsubnet != NULL; currsubnet = currsubnet->next) {
// Check if the ip falls in under the subnet....
if((ipaddr & currsubnet->subnet_mask) == currsubnet->subnet_addr) {
return Dp;
}
}
}
return NULL;
}
/**
* Returns a pointer to the IfDesc whose subnet matches
* the supplied IP adress. The IP must match a interfaces
* subnet, or any configured allowed subnet on a interface.
*/
struct IfDesc *getIfByVifIndex( unsigned vifindex ) {
struct IfDesc *Dp;
if(vifindex>0) {
for ( Dp = IfDescVc; Dp < IfDescEp; Dp++ ) {
if(Dp->index == vifindex) {
return Dp;
}
}
}
return NULL;
}
/**
* Function that checks if a given ipaddress is a valid
* address for the supplied VIF.
*/
int isAdressValidForIf( struct IfDesc* intrface, uint32 ipaddr ) {
struct SubnetList *currsubnet;
if(intrface == NULL) {
return 0;
}
// Loop through all registered allowed nets of the VIF...
for(currsubnet = intrface->allowednets; currsubnet != NULL; currsubnet = currsubnet->next) {
/*
IF_DEBUG log(LOG_DEBUG, 0, "Testing %s for subnet %s, mask %s: Result net: %s",
inetFmt(ipaddr, s1),
inetFmt(currsubnet->subnet_addr, s2),
inetFmt(currsubnet->subnet_mask, s3),
inetFmt((ipaddr & currsubnet->subnet_mask), s4)
);
*/
// Check if the ip falls in under the subnet....
if((ipaddr & currsubnet->subnet_mask) == currsubnet->subnet_addr) {
return 1;
}
}
return 0;
}