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| author | kris <kris@FreeBSD.org> | 2001-06-01 10:02:28 +0000 |
|---|---|---|
| committer | kris <kris@FreeBSD.org> | 2001-06-01 10:02:28 +0000 |
| commit | e1524eb20ca44614d4942a0b92929a02e67dce44 (patch) | |
| tree | 9bd8aa0fc8cabc5d0cc01510f30e42d4a12277e2 /sys/netinet/ip_var.h | |
| parent | 83f8b7087fd25f91158a6a096fad46b33b513773 (diff) | |
| download | FreeBSD-src-e1524eb20ca44614d4942a0b92929a02e67dce44.zip FreeBSD-src-e1524eb20ca44614d4942a0b92929a02e67dce44.tar.gz | |
Add ``options RANDOM_IP_ID'' which randomizes the ID field of IP packets.
This closes a minor information leak which allows a remote observer to
determine the rate at which the machine is generating packets, since the
default behaviour is to increment a counter for each packet sent.
Reviewed by: -net
Obtained from: OpenBSD
Diffstat (limited to 'sys/netinet/ip_var.h')
| -rw-r--r-- | sys/netinet/ip_var.h | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/sys/netinet/ip_var.h b/sys/netinet/ip_var.h index bc8b797..6354d84 100644 --- a/sys/netinet/ip_var.h +++ b/sys/netinet/ip_var.h @@ -138,7 +138,9 @@ struct route; struct sockopt; extern struct ipstat ipstat; +#ifndef RANDOM_IP_ID extern u_short ip_id; /* ip packet ctr, for ids */ +#endif extern int ip_defttl; /* default IP ttl */ extern int ipforwarding; /* ip forwarding */ extern struct route ipforward_rt; /* ip forwarding cached route */ @@ -164,6 +166,10 @@ void ip_slowtimo __P((void)); struct mbuf * ip_srcroute __P((void)); void ip_stripoptions __P((struct mbuf *, struct mbuf *)); +#ifdef RANDOM_IP_ID +u_int16_t + ip_randomid __P((void)); +#endif int rip_ctloutput __P((struct socket *, struct sockopt *)); void rip_ctlinput __P((int, struct sockaddr *, void *)); void rip_init __P((void)); |
