From 8d3eaf171b8426e26b2c400ab0af8e9100e9793f Mon Sep 17 00:00:00 2001 From: ru Date: Mon, 21 Jan 2002 13:59:42 +0000 Subject: RFC1122 requires that addresses of the form { 127, } MUST NOT appear outside a host. PR: 30792, 33996 Obtained from: ip_input.c MFC after: 1 week --- sys/netinet/ip_output.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) diff --git a/sys/netinet/ip_output.c b/sys/netinet/ip_output.c index 6185db0..af06486 100644 --- a/sys/netinet/ip_output.c +++ b/sys/netinet/ip_output.c @@ -422,9 +422,19 @@ ip_output(m0, opt, ro, flags, imo) goto bad; } + /* 127/8 must not appear on wire - RFC1122. */ + if ((ntohl(ip->ip_dst.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET || + (ntohl(ip->ip_src.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET) { + if ((ifp->if_flags & IFF_LOOPBACK) == 0) { + ipstat.ips_badaddr++; + error = EADDRNOTAVAIL; + goto bad; + } + } + /* * Look for broadcast address and - * and verify user is allowed to send + * verify user is allowed to send * such a packet. */ if (isbroadcast) { -- cgit v1.1