From 26f16ebeb1a790823e21cca2b3e720fc34bc1620 Mon Sep 17 00:00:00 2001 From: Ruslan Ermilov Date: Thu, 25 Mar 2004 08:46:27 +0000 Subject: [PATCH] Untangle IP multicast routing interaction with delayed payload checksums. Compute the payload checksum for a locally originated IP multicast where God intended, in ip_mloopback(), rather than doing it in ip_output() and only when multicast router is active. This is more correct as we do not fool ip_input() that the packet has the correct payload checksum when in fact it does not (when multicast router is inactive). This is also more efficient if we don't join the multicast group we send to, thus allowing the hardware to checksum the payload. --- sys/netinet/ip_output.c | 16 +++------------- 1 file changed, 3 insertions(+), 13 deletions(-) diff --git a/sys/netinet/ip_output.c b/sys/netinet/ip_output.c index a83cfa94f7f..ccab9af024c 100644 --- a/sys/netinet/ip_output.c +++ b/sys/netinet/ip_output.c @@ -338,18 +338,6 @@ ip_output(struct mbuf *m, struct mbuf *opt, struct route *ro, ip->ip_src = IA_SIN(ia)->sin_addr; } - if (ip_mrouter && (flags & IP_FORWARDING) == 0) { - /* - * XXX - * delayed checksums are not currently - * compatible with IP multicast routing - */ - if (m->m_pkthdr.csum_flags & CSUM_DELAY_DATA) { - in_delayed_cksum(m); - m->m_pkthdr.csum_flags &= - ~CSUM_DELAY_DATA; - } - } IN_LOOKUP_MULTI(pkt_dst, ifp, inm); if (inm != NULL && (imo == NULL || imo->imo_multicast_loop)) { @@ -2232,8 +2220,10 @@ ip_mloopback(ifp, m, dst, hlen) copym->m_pkthdr.rcvif = ifp; ip_input(copym); #else - /* if the checksum hasn't been computed, mark it as valid */ + /* If needed, compute the checksum and mark it as valid. */ if (copym->m_pkthdr.csum_flags & CSUM_DELAY_DATA) { + in_delayed_cksum(copym); + copym->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA; copym->m_pkthdr.csum_flags |= CSUM_DATA_VALID | CSUM_PSEUDO_HDR; copym->m_pkthdr.csum_data = 0xffff;