WSL2-Linux-Kernel/include/net
Eric Dumazet 04ca6973f7 ip: make IP identifiers less predictable
In "Counting Packets Sent Between Arbitrary Internet Hosts", Jeffrey and
Jedidiah describe ways exploiting linux IP identifier generation to
infer whether two machines are exchanging packets.

With commit 73f156a6e8 ("inetpeer: get rid of ip_id_count"), we
changed IP id generation, but this does not really prevent this
side-channel technique.

This patch adds a random amount of perturbation so that IP identifiers
for a given destination [1] are no longer monotonically increasing after
an idle period.

Note that prandom_u32_max(1) returns 0, so if generator is used at most
once per jiffy, this patch inserts no hole in the ID suite and do not
increase collision probability.

This is jiffies based, so in the worst case (HZ=1000), the id can
rollover after ~65 seconds of idle time, which should be fine.

We also change the hash used in __ip_select_ident() to not only hash
on daddr, but also saddr and protocol, so that ICMP probes can not be
used to infer information for other protocols.

For IPv6, adds saddr into the hash as well, but not nexthdr.

If I ping the patched target, we can see ID are now hard to predict.

21:57:11.008086 IP (...)
    A > target: ICMP echo request, seq 1, length 64
21:57:11.010752 IP (... id 2081 ...)
    target > A: ICMP echo reply, seq 1, length 64

21:57:12.013133 IP (...)
    A > target: ICMP echo request, seq 2, length 64
21:57:12.015737 IP (... id 3039 ...)
    target > A: ICMP echo reply, seq 2, length 64

21:57:13.016580 IP (...)
    A > target: ICMP echo request, seq 3, length 64
21:57:13.019251 IP (... id 3437 ...)
    target > A: ICMP echo reply, seq 3, length 64

[1] TCP sessions uses a per flow ID generator not changed by this patch.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Jeffrey Knockel <jeffk@cs.unm.edu>
Reported-by: Jedidiah R. Crandall <crandall@cs.unm.edu>
Cc: Willy Tarreau <w@1wt.eu>
Cc: Hannes Frederic Sowa <hannes@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-28 18:46:34 -07:00
..
9p 9pnet: p9_client->conn field is unused. Remove it. 2014-03-25 16:38:16 -05:00
bluetooth Bluetooth: Clearly distinguish mgmt LTK type from authenticated property 2014-05-23 11:24:04 -07:00
caif caif_hsi.h: Remove extern from function prototypes 2013-09-23 16:29:41 -04:00
irda include/net/: Fix FSF address in file headers 2013-12-06 12:37:56 -05:00
iucv
netfilter netfilter: nf_tables: 64bit stats need some extra synchronization 2014-07-14 12:00:17 +02:00
netns Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf 2014-07-16 15:27:16 -07:00
nfc NFC: Add RAW socket type support for SOCKPROTO_RAW 2014-05-20 00:06:04 +02:00
phonet
sctp net: sctp: migrate most recently used transport to ktime 2014-06-11 12:23:17 -07:00
tc_act net_sched: act: hide struct tcf_common from API 2014-02-12 19:23:32 -05:00
6lowpan.h 6lowpan: include net/net_namespace.h on 6lowpan namepsace header 2014-04-20 18:18:55 -04:00
Space.h drivers: net: Include new header file in sbni.c 2013-12-19 18:51:20 -05:00
act_api.h net_sched: act: refuse to remove bound action outside 2014-02-12 19:23:32 -05:00
addrconf.h net: ipv6: Introduce ip6_sk_dst_hoplimit. 2014-04-30 13:31:26 -04:00
af_ieee802154.h ieee802154: add dgram sockopts for security control 2014-05-16 17:23:41 -04:00
af_rxrpc.h af_rxrpc.h: Remove extern from function prototypes 2013-07-31 17:50:01 -07:00
af_unix.h af_unix: improve STREAM behavior with fragmented memory 2013-08-10 01:16:44 -07:00
af_vsock.h vsock: Make transport the proto owner 2014-05-05 13:13:50 -04:00
ah.h
arp.h arp: make arp_invalidate static 2013-12-28 17:02:46 -05:00
atmclip.h
ax25.h ax25.h: Remove extern from function prototypes 2013-07-31 17:50:02 -07:00
ax88796.h
busy_poll.h sched, net: Fixup busy_loop_us_clock() 2014-01-13 17:39:11 +01:00
cfg80211-wext.h
cfg80211.h Merge git://git.kernel.org/pub/scm/linux/kernel/git/jberg/mac80211-next 2014-05-22 13:58:36 -04:00
checksum.h net: Allow csum_add to be provided in arch 2014-05-05 15:26:29 -04:00
cipso_ipv4.h cipso: cleanup cipso_v4_translate() when !CONFIG_NETLABEL 2013-12-10 17:56:54 -05:00
cls_cgroup.h cgroup: clean up cgroup_subsys names and initialization 2014-02-08 10:36:58 -05:00
codel.h net: introduce reciprocal_scale helper and convert users 2014-01-21 23:17:20 -08:00
compat.h compat.h: Remove extern from function prototypes 2013-09-20 14:49:32 -04:00
datalink.h net: Move prototype declaration to header file include/net/datalink.h from net/ipx/af_ipx.c 2014-02-09 17:32:50 -08:00
dcbevent.h include/net/: Fix FSF address in file headers 2013-12-06 12:37:56 -05:00
dcbnl.h include/net/: Fix FSF address in file headers 2013-12-06 12:37:56 -05:00
dn.h net: Move prototype declaration to header file include/net/dn.h from net/decnet/af_decnet.c 2014-02-09 17:32:49 -08:00
dn_dev.h dn_dev: add support for IFA_FLAGS nl attribute 2013-12-10 21:50:00 -05:00
dn_fib.h decnet (dn*.h): Remove extern from function prototypes 2013-09-20 14:49:32 -04:00
dn_neigh.h decnet (dn*.h): Remove extern from function prototypes 2013-09-20 14:49:32 -04:00
dn_nsp.h decnet (dn*.h): Remove extern from function prototypes 2013-09-20 14:49:32 -04:00
dn_route.h net: Move prototype declaration to appropriate header file from decnet/af_decnet.c 2014-02-09 17:32:49 -08:00
dsa.h net: dsa: add ds_to_priv 2014-04-30 13:31:25 -04:00
dsfield.h
dst.h ipv4: add a sock pointer to dst->output() path. 2014-04-15 13:47:15 -04:00
dst_ops.h
esp.h net: move pskb_put() to core code 2013-11-07 19:28:58 -05:00
ethoc.h net: ethoc: set up MII management bus clock 2014-02-04 20:19:51 -08:00
fib_rules.h fib_rules.h: Remove extern from function prototypes 2013-09-20 14:49:33 -04:00
firewire.h
flow.h ipv4, fib: pass LOOPBACK_IFINDEX instead of 0 to flowi4_iif 2014-04-16 15:05:11 -04:00
flow_keys.h flow_dissector: factor out the ports extraction in skb_flow_get_ports 2013-10-03 15:36:37 -04:00
flowcache.h flowcache: Make flow cache name space aware 2014-02-12 07:02:11 +01:00
garp.h garp.h: Remove extern from function prototypes 2013-09-20 14:49:33 -04:00
gen_stats.h gen_stats.h: Remove extern from function prototypes 2013-09-20 14:49:33 -04:00
genetlink.h genl: Add genlmsg_new_unicast() for unicast message allocation 2014-01-06 15:51:53 -08:00
gre.h gre: Call gso_make_checksum 2014-06-04 22:46:38 -07:00
gro_cells.h
icmp.h icmp.h: Remove extern from function prototypes 2013-09-20 14:49:33 -04:00
ieee80211_radiotap.h mac80211: propagate STBC / LDPC flags to radiotap 2014-02-06 09:34:58 +01:00
ieee802154.h ieee802154: add definitions for link-layer security and header functions 2014-05-15 15:51:42 -04:00
ieee802154_netdev.h ieee802154, mac802154: implement devkey record option 2014-05-16 17:23:42 -04:00
if_inet6.h ipv6: move DAD and addrconf_verify processing to workqueue 2014-03-28 16:54:50 -04:00
inet6_connection_sock.h ipv4: add a sock pointer to ip_queue_xmit() 2014-04-15 12:58:34 -04:00
inet6_hashtables.h ipv6: split inet6_ehashfn to hash functions per compilation unit 2013-10-19 19:45:34 -04:00
inet_common.h inet*.h: Remove extern from function prototypes 2013-09-21 14:01:38 -04:00
inet_connection_sock.h ipv4: add a sock pointer to ip_queue_xmit() 2014-04-15 12:58:34 -04:00
inet_ecn.h tunnel: fix RFC number in comment for INET_ECN_decapsulate() 2014-05-07 15:30:52 -04:00
inet_frag.h inet: remove old fragmentation hash initializing 2013-10-23 17:01:41 -04:00
inet_hashtables.h net: Use a more standard macro for INET_ADDR_COOKIE 2014-05-14 16:07:23 -04:00
inet_sock.h net: support marking accepting TCP sockets 2014-05-13 18:35:09 -04:00
inet_timewait_sock.h ipv6: tcp: fix flowlabel value in ACK messages send from TIME_WAIT 2014-01-17 17:56:33 -08:00
inetpeer.h Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2014-06-03 23:32:12 -07:00
ip.h ip: make IP identifiers less predictable 2014-07-28 18:46:34 -07:00
ip6_checksum.h udp: Generic functions to set checksum 2014-06-04 22:46:38 -07:00
ip6_fib.h ipv6: do not overwrite inetpeer metrics prematurely 2014-03-27 15:09:07 -04:00
ip6_route.h Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2014-05-24 00:32:30 -04:00
ip6_tunnel.h net: unify the pcpu_tstats and br_cpu_netstats as one 2014-01-04 20:10:24 -05:00
ip_fib.h ip*.h: Remove extern from function prototypes 2013-09-21 14:01:38 -04:00
ip_tunnels.h ipv4: add a sock pointer to dst->output() path. 2014-04-15 13:47:15 -04:00
ip_vs.h arch: Mass conversion of smp_mb__*() 2014-04-18 14:20:48 +02:00
ipcomp.h
ipconfig.h
ipv6.h inetpeer: get rid of ip_id_count 2014-06-02 11:00:41 -07:00
ipx.h net: Move prototype declaration to header file include/net/ipx.h from net/ipx/af_ipx.c 2014-02-09 17:32:50 -08:00
iw_handler.h iw_handler.h: Remove extern from function prototypes 2013-09-21 14:01:39 -04:00
lapb.h lapb.h: Remove extern from function prototypes 2013-09-21 14:01:38 -04:00
lib80211.h hostap: Don't use create_proc_read_entry() 2013-04-29 15:41:56 -04:00
llc.h llc: make lock static 2014-01-03 20:56:48 -05:00
llc_c_ac.h llc*.h: Remove extern from function prototypes 2013-09-21 14:01:38 -04:00
llc_c_ev.h llc*.h: Remove extern from function prototypes 2013-09-21 14:01:38 -04:00
llc_c_st.h
llc_conn.h llc*.h: Remove extern from function prototypes 2013-09-21 14:01:38 -04:00
llc_if.h llc*.h: Remove extern from function prototypes 2013-09-21 14:01:38 -04:00
llc_pdu.h net: llc: fix order of evaluation in llc_conn_ac_inc_vr_by_1 2014-01-01 22:22:43 -05:00
llc_s_ac.h llc*.h: Remove extern from function prototypes 2013-09-21 14:01:38 -04:00
llc_s_ev.h llc*.h: Remove extern from function prototypes 2013-09-21 14:01:38 -04:00
llc_s_st.h
llc_sap.h llc*.h: Remove extern from function prototypes 2013-09-21 14:01:38 -04:00
mac80211.h mac80211: add a single-transaction driver op to switch contexts 2014-05-26 11:04:41 +02:00
mac802154.h ieee802154: add header structs with endiannes and operations 2014-03-14 22:15:26 -04:00
mip6.h include/net/: Fix FSF address in file headers 2013-12-06 12:37:56 -05:00
mld.h net: ipv6: mld: get rid of MLDV2_MRC and simplify calculation 2013-09-04 14:53:20 -04:00
mrp.h Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2013-10-01 17:06:14 -04:00
ndisc.h ndisc.h: Remove extern from function prototypes 2013-09-21 14:01:39 -04:00
neighbour.h neigh: sysctl - simplify address calculation of gc_* variables 2014-07-14 14:32:51 -07:00
net_namespace.h 6lowpan: nuke net_ieee802154_lowpan() accessor when 6lowpan is disabled 2014-04-24 12:36:00 -04:00
net_ratelimit.h
netdma.h
netevent.h netevent/netlink.h: Remove extern from function prototypes 2013-09-21 14:01:39 -04:00
netlabel.h Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2014-01-25 11:17:34 -08:00
netlink.h netevent/netlink.h: Remove extern from function prototypes 2013-09-21 14:01:39 -04:00
netprio_cgroup.h cgroup: clean up cgroup_subsys names and initialization 2014-02-08 10:36:58 -05:00
netrom.h netrom.h: Remove extern from function prototypes 2013-09-21 14:01:39 -04:00
nexthop.h
nl802154.h ieee802154: use ieee802154_addr instead of *_sa variants 2014-03-14 22:15:26 -04:00
p8022.h p8022.h: Remove extern from function prototypes 2013-09-21 14:01:39 -04:00
ping.h ipv6: make IPV6_RECVPKTINFO work for ipv4 datagrams 2014-01-19 19:53:18 -08:00
pkt_cls.h sched, cls: check if we could overwrite actions when changing a filter 2014-04-27 23:42:39 -04:00
pkt_sched.h net_sched: drr: warn when qdisc is not work conserving 2014-06-11 15:50:59 -07:00
protocol.h net: Eliminate no_check from protosw 2014-05-23 16:28:53 -04:00
psnap.h psnap.h: Remove extern from function prototypes 2013-09-23 01:51:08 -04:00
raw.h raw/rawv6.h: Remove extern from function prototypes 2013-09-23 01:51:08 -04:00
rawv6.h raw/rawv6.h: Remove extern from function prototypes 2013-09-23 01:51:08 -04:00
red.h reciprocal_divide: update/correction of the algorithm 2014-01-21 23:17:20 -08:00
regulatory.h cfg80211: Enable GO operation on additional channels 2014-04-09 10:55:34 +02:00
request_sock.h inet: includes a sock_common in request_sock 2013-10-10 00:08:07 -04:00
rose.h rose.h: Remove extern from function prototypes 2013-09-23 01:51:08 -04:00
route.h ipv4: remove ip_rt_dump from route.c 2014-03-24 12:45:01 -04:00
rtnetlink.h rtnl: make ifla_policy static 2014-02-18 18:15:42 -05:00
sch_generic.h sched, cls: check if we could overwrite actions when changing a filter 2014-04-27 23:42:39 -04:00
scm.h scm.h: Remove extern from function prototypes 2013-09-23 01:51:09 -04:00
secure_seq.h inetpeer: get rid of ip_id_count 2014-06-02 11:00:41 -07:00
slhc_vj.h
snmp.h net: clean up snmp stats code 2014-05-07 16:06:05 -04:00
sock.h net: fix sparse warning in sk_dst_set() 2014-07-02 17:03:06 -07:00
stp.h stp.h: Remove extern from function prototypes 2013-09-23 01:51:09 -04:00
tcp.h tcp: add gfp parameter to tcp_fragment 2014-06-10 22:30:58 -07:00
tcp_memcontrol.h tcp_memcontrol: Kill struct tcp_memcontrol 2013-10-21 18:43:02 -04:00
tcp_states.h
timewait_sock.h
transp_v6.h ipv6: make IPV6_RECVPKTINFO work for ipv4 datagrams 2014-01-19 19:53:18 -08:00
tso.h net: Add a software TSO helper API 2014-05-22 14:57:15 -04:00
udp.h udp: call __skb_checksum_complete when doing full checksum 2014-06-15 01:00:49 -07:00
udplite.h udplite.h: Remove extern from function prototypes 2013-09-23 16:29:40 -04:00
vsock_addr.h VSOCK: Move af_vsock.h and vsock_addr.h to include/net 2013-07-27 22:14:06 -07:00
vxlan.h vxlan: Add support for UDP checksums (v4 sending, v6 zero csums) 2014-06-04 22:46:39 -07:00
wext.h wext.h: Remove extern from function prototypes 2013-09-23 16:29:40 -04:00
wimax.h wimax: Spelling s/than/that/, wording s/destinatary/recipient/ 2014-05-05 15:37:55 +02:00
wpan-phy.h ieee802154: add netlink APIs for smartMAC configuration 2014-02-17 16:42:39 -05:00
x25.h x25.h: Remove extern from function prototypes 2013-09-23 16:29:41 -04:00
x25device.h
xfrm.h xfrm: Remove useless xfrm_audit struct. 2014-04-23 08:21:04 +02:00