You know, I really, really hate not having used up all the bits in the ip header. There is some encouraging work in the conex working group http://datatracker.ietf.org/wg/conex/charter/ that needs this bit in order to implement at least part of their core idea. So I think today would be a good day to commit to using up that last bit in cerowrt. ---------- Forwarded message ---------- From: Martin Lucina Date: Sun, Apr 1, 2012 at 1:53 PM Subject: [PATCH] Implement IP_EVIL socket option (RFC 3514) To: linux-kernel@vger.kernel.org, netdev@vger.kernel.org Cc: Martin Lucina This patch implements the IP_EVIL socket option, allowing user-space applications to set the Security Flag in the IPv4 Header, aka "evil" bit, as defined in RFC 3514. Signed-off-by: Martin Lucina --- include/linux/in.h | 1 + include/net/inet_sock.h | 1 + net/ipv4/af_inet.c | 1 + net/ipv4/ip_output.c | 2 ++ net/ipv4/ip_sockglue.c | 9 ++++++++- 5 files changed, 13 insertions(+), 1 deletions(-) diff --git a/include/linux/in.h b/include/linux/in.h index e0337f1..6814c0f 100644 --- a/include/linux/in.h +++ b/include/linux/in.h @@ -86,6 +86,7 @@ struct in_addr { #define IP_MINTTL 21 #define IP_NODEFRAG 22 +#define IP_EVIL 23 /* IP_MTU_DISCOVER values */ #define IP_PMTUDISC_DONT 0 /* Never send DF frames */ diff --git a/include/net/inet_sock.h b/include/net/inet_sock.h index ae17e13..37aaf9b 100644 --- a/include/net/inet_sock.h +++ b/include/net/inet_sock.h @@ -168,6 +168,7 @@ struct inet_sock { transparent:1, mc_all:1, nodefrag:1; + __u8 evil; __u8 rcv_tos; int uc_index; int mc_index; diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c index 10e3751..b165dfb 100644 --- a/net/ipv4/af_inet.c +++ b/net/ipv4/af_inet.c @@ -356,6 +356,7 @@ lookup_protocol: inet->is_icsk = (INET_PROTOSW_ICSK & answer_flags) != 0; inet->nodefrag = 0; + inet->evil = 0; /* Don't be evil */ if (SOCK_RAW == sock->type) { inet->inet_num = protocol; diff --git a/net/ipv4/ip_output.c b/net/ipv4/ip_output.c index 4910176..c1b4b15 100644 --- a/net/ipv4/ip_output.c +++ b/net/ipv4/ip_output.c @@ -157,6 +157,8 @@ int ip_build_and_send_pkt(struct sk_buff *skb, struct sock *sk, iph->frag_off = htons(IP_DF); else iph->frag_off = 0; + if (inet->evil) + iph->frag_off |= 1<<15; iph->ttl = ip_select_ttl(inet, &rt->dst); iph->daddr = (opt && opt->opt.srr ? opt->opt.faddr : daddr); iph->saddr = saddr; diff --git a/net/ipv4/ip_sockglue.c b/net/ipv4/ip_sockglue.c index 2fd0fba..f26d45c 100644 --- a/net/ipv4/ip_sockglue.c +++ b/net/ipv4/ip_sockglue.c @@ -463,7 +463,8 @@ static int do_ip_setsockopt(struct sock *sk, int level, (1<nodefrag = val ? 1 : 0; break; + case IP_EVIL: + inet->evil = val ? 1 : 0; + break; case IP_MTU_DISCOVER: if (val < IP_PMTUDISC_DONT || val > IP_PMTUDISC_PROBE) goto e_inval; @@ -1176,6 +1180,9 @@ static int do_ip_getsockopt(struct sock *sk, int level, int optname, case IP_NODEFRAG: val = inet->nodefrag; break; + case IP_EVIL: + val = inet->evil; + break; case IP_MTU_DISCOVER: val = inet->pmtudisc; break; -- 1.7.9.1 -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html -- Dave Täht SKYPE: davetaht US Tel: 1-239-829-5608 http://www.bufferbloat.net