From ffd77d9ba5a1376d64ccbb2909a7179c05de81bc Mon Sep 17 00:00:00 2001 From: bms Date: Tue, 12 Jun 2007 16:24:56 +0000 Subject: Import rewrite of IPv4 socket multicast layer to support source-specific and protocol-independent host mode multicast. The code is written to accomodate IPv6, IGMPv3 and MLDv2 with only a little additional work. This change only pertains to FreeBSD's use as a multicast end-station and does not concern multicast routing; for an IGMPv3/MLDv2 router implementation, consider the XORP project. The work is based on Wilbert de Graaf's IGMPv3 code drop for FreeBSD 4.6, which is available at: http://www.kloosterhof.com/wilbert/igmpv3.html Summary * IPv4 multicast socket processing is now moved out of ip_output.c into a new module, in_mcast.c. * The in_mcast.c module implements the IPv4 legacy any-source API in terms of the protocol-independent source-specific API. * Source filters are lazy allocated as the common case does not use them. They are part of per inpcb state and are covered by the inpcb lock. * struct ip_mreqn is now supported to allow applications to specify multicast joins by interface index in the legacy IPv4 any-source API. * In UDP, an incoming multicast datagram only requires that the source port matches the 4-tuple if the socket was already bound by source port. An unbound socket SHOULD be able to receive multicasts sent from an ephemeral source port. * The UDP socket multicast filter mode defaults to exclusive, that is, sources present in the per-socket list will be blocked from delivery. * The RFC 3678 userland functions have been added to libc: setsourcefilter, getsourcefilter, setipv4sourcefilter, getipv4sourcefilter. * Definitions for IGMPv3 are merged but not yet used. * struct sockaddr_storage is now referenced from . It is therefore defined there if not already declared in the same way as for the C99 types. * The RFC 1724 hack (specify 0.0.0.0/8 addresses to IP_MULTICAST_IF which are then interpreted as interface indexes) is now deprecated. * A patch for the Rhyolite.com routed in the FreeBSD base system is available in the -net archives. This only affects individuals running RIPv1 or RIPv2 via point-to-point and/or unnumbered interfaces. * Make IPv6 detach path similar to IPv4's in code flow; functionally same. * Bump __FreeBSD_version to 700048; see UPDATING. This work was financially supported by another FreeBSD committer. Obtained from: p4://bms_netdev Submitted by: Wilbert de Graaf (original work) Reviewed by: rwatson (locking), silence from fenner, net@ (but with encouragement) --- sys/netinet/in.c | 165 +------------------------------------------------------ 1 file changed, 1 insertion(+), 164 deletions(-) (limited to 'sys/netinet/in.c') diff --git a/sys/netinet/in.c b/sys/netinet/in.c index dd20e00..d0c36fa 100644 --- a/sys/netinet/in.c +++ b/sys/netinet/in.c @@ -49,10 +49,7 @@ #include #include #include - -#include - -static MALLOC_DEFINE(M_IPMADDR, "in_multi", "internet multicast address"); +#include static int in_mask2len(struct in_addr *); static void in_len2mask(struct in_addr *, int); @@ -74,17 +71,6 @@ SYSCTL_INT(_net_inet_ip, OID_AUTO, same_prefix_carp_only, CTLFLAG_RW, &sameprefixcarponly, 0, "Refuse to create same prefixes on different interfaces"); -/* - * The IPv4 multicast list (in_multihead and associated structures) are - * protected by the global in_multi_mtx. See in_var.h for more details. For - * now, in_multi_mtx is marked as recursible due to IGMP's calling back into - * ip_output() to send IGMP packets while holding the lock; this probably is - * not quite desirable. - */ -struct in_multihead in_multihead; /* XXX BSS initialization */ -struct mtx in_multi_mtx; -MTX_SYSINIT(in_multi_mtx, &in_multi_mtx, "in_multi_mtx", MTX_DEF | MTX_RECURSE); - extern struct inpcbinfo ripcbinfo; extern struct inpcbinfo udbinfo; @@ -977,155 +963,6 @@ in_broadcast(struct in_addr in, struct ifnet *ifp) } /* - * Add an address to the list of IP multicast addresses for a given interface. - */ -struct in_multi * -in_addmulti(struct in_addr *ap, struct ifnet *ifp) -{ - struct in_multi *inm; - - inm = NULL; - - IFF_LOCKGIANT(ifp); - IN_MULTI_LOCK(); - - IN_LOOKUP_MULTI(*ap, ifp, inm); - if (inm != NULL) { - /* - * If we already joined this group, just bump the - * refcount and return it. - */ - KASSERT(inm->inm_refcount >= 1, - ("%s: bad refcount %d", __func__, inm->inm_refcount)); - ++inm->inm_refcount; - } else do { - struct sockaddr_in sin; - struct ifmultiaddr *ifma; - struct in_multi *ninm; - int error; - - bzero(&sin, sizeof sin); - sin.sin_family = AF_INET; - sin.sin_len = sizeof(struct sockaddr_in); - sin.sin_addr = *ap; - - /* - * Check if a link-layer group is already associated - * with this network-layer group on the given ifnet. - * If so, bump the refcount on the existing network-layer - * group association and return it. - */ - error = if_addmulti(ifp, (struct sockaddr *)&sin, &ifma); - if (error) - break; - if (ifma->ifma_protospec != NULL) { - inm = (struct in_multi *)ifma->ifma_protospec; -#ifdef INVARIANTS - if (inm->inm_ifma != ifma || inm->inm_ifp != ifp || - inm->inm_addr.s_addr != ap->s_addr) - panic("%s: ifma is inconsistent", __func__); -#endif - ++inm->inm_refcount; - break; - } - - /* - * A new membership is needed; construct it and - * perform the IGMP join. - */ - ninm = malloc(sizeof(*ninm), M_IPMADDR, M_NOWAIT | M_ZERO); - if (ninm == NULL) { - if_delmulti_ifma(ifma); - break; - } - ninm->inm_addr = *ap; - ninm->inm_ifp = ifp; - ninm->inm_ifma = ifma; - ninm->inm_refcount = 1; - ifma->ifma_protospec = ninm; - LIST_INSERT_HEAD(&in_multihead, ninm, inm_link); - - igmp_joingroup(ninm); - - inm = ninm; - } while (0); - - IN_MULTI_UNLOCK(); - IFF_UNLOCKGIANT(ifp); - - return (inm); -} - -/* - * Delete a multicast address record. - * It is OK to call this routine if the underlying ifnet went away. - * - * XXX: To deal with the ifp going away, we cheat; the link-layer code in net - * will set ifma_ifp to NULL when the associated ifnet instance is detached - * from the system. - * The only reason we need to violate layers and check ifma_ifp here at all - * is because certain hardware drivers still require Giant to be held, - * and it must always be taken before other locks. - */ -void -in_delmulti(struct in_multi *inm) -{ - struct ifnet *ifp; - - KASSERT(inm->inm_ifma != NULL, ("%s: no ifma", __func__)); - ifp = inm->inm_ifma->ifma_ifp; - - if (ifp != NULL) { - /* - * Sanity check that netinet's notion of ifp is the - * same as net's. - */ - KASSERT(inm->inm_ifp == ifp, ("%s: bad ifp", __func__)); - IFF_LOCKGIANT(ifp); - } - - IN_MULTI_LOCK(); - in_delmulti_locked(inm); - IN_MULTI_UNLOCK(); - - if (ifp != NULL) - IFF_UNLOCKGIANT(ifp); -} - -/* - * Delete a multicast address record, with locks held. - * - * It is OK to call this routine if the ifp went away. - * Assumes that caller holds the IN_MULTI lock, and that - * Giant was taken before other locks if required by the hardware. - */ -void -in_delmulti_locked(struct in_multi *inm) -{ - struct ifmultiaddr *ifma; - - IN_MULTI_LOCK_ASSERT(); - KASSERT(inm->inm_refcount >= 1, ("%s: freeing freed inm", __func__)); - - if (--inm->inm_refcount == 0) { - igmp_leavegroup(inm); - - ifma = inm->inm_ifma; -#ifdef DIAGNOSTIC - printf("%s: purging ifma %p\n", __func__, ifma); -#endif - KASSERT(ifma->ifma_protospec == inm, - ("%s: ifma_protospec != inm", __func__)); - ifma->ifma_protospec = NULL; - - LIST_REMOVE(inm, inm_link); - free(inm, M_IPMADDR); - - if_delmulti_ifma(ifma); - } -} - -/* * Delete all IPv4 multicast address records, and associated link-layer * multicast address records, associated with ifp. */ -- cgit v1.1