linux-stable/net/ipv4
Martin KaFai Lau 331fca4315 bpf: tcp: Add bpf_skops_hdr_opt_len() and bpf_skops_write_hdr_opt()
The bpf prog needs to parse the SYN header to learn what options have
been sent by the peer's bpf-prog before writing its options into SYNACK.
This patch adds a "syn_skb" arg to tcp_make_synack() and send_synack().
This syn_skb will eventually be made available (as read-only) to the
bpf prog.  This will be the only SYN packet available to the bpf
prog during syncookie.  For other regular cases, the bpf prog can
also use the saved_syn.

When writing options, the bpf prog will first be called to tell the
kernel its required number of bytes.  It is done by the new
bpf_skops_hdr_opt_len().  The bpf prog will only be called when the new
BPF_SOCK_OPS_WRITE_HDR_OPT_CB_FLAG is set in tp->bpf_sock_ops_cb_flags.
When the bpf prog returns, the kernel will know how many bytes are needed
and then update the "*remaining" arg accordingly.  4 byte alignment will
be included in the "*remaining" before this function returns.  The 4 byte
aligned number of bytes will also be stored into the opts->bpf_opt_len.
"bpf_opt_len" is a newly added member to the struct tcp_out_options.

Then the new bpf_skops_write_hdr_opt() will call the bpf prog to write the
header options.  The bpf prog is only called if it has reserved spaces
before (opts->bpf_opt_len > 0).

The bpf prog is the last one getting a chance to reserve header space
and writing the header option.

These two functions are half implemented to highlight the changes in
TCP stack.  The actual codes preparing the bpf running context and
invoking the bpf prog will be added in the later patch with other
necessary bpf pieces.

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/bpf/20200820190052.2885316-1-kafai@fb.com
2020-08-24 14:35:00 -07:00
..
bpfilter net: Revert "net: optimize the sockptr_t for unified kernel/user address spaces" 2020-08-10 12:06:44 -07:00
netfilter Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next 2020-08-05 20:13:21 -07:00
af_inet.c net: remove compat_sock_common_{get,set}sockopt 2020-07-19 18:16:40 -07:00
ah4.c inet: Use fallthrough; 2020-03-12 15:55:00 -07:00
arp.c inet: Use fallthrough; 2020-03-12 15:55:00 -07:00
bpf_tcp_ca.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next 2020-03-30 19:52:37 -07:00
cipso_ipv4.c net: ipv4: kerneldoc fixes 2020-07-13 17:20:39 -07:00
datagram.c inet: stop leaking jiffies on the wire 2019-11-01 14:57:52 -07:00
devinet.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2020-05-31 17:48:46 -07:00
esp4.c ESP: Export esp_output_fill_trailer function 2020-02-19 13:52:32 +01:00
esp4_offload.c net: Add MODULE_DESCRIPTION entries to network modules 2020-06-20 21:33:57 -07:00
fib_frontend.c ipv4: nexthop version of fib_info_nh_uses_dev 2020-05-26 16:06:07 -07:00
fib_lookup.h net: add net available in build_state 2020-03-29 22:30:57 -07:00
fib_notifier.c net: fib_notifier: propagate extack down to the notifier block callback 2019-10-04 11:10:56 -07:00
fib_rules.c fib: use indirect call wrappers in the most common fib_rules_ops 2020-07-28 17:42:31 -07:00
fib_semantics.c net: Fix the arp error in some cases 2020-06-18 20:21:51 -07:00
fib_trie.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2020-08-02 01:02:12 -07:00
fou.c net: Add MODULE_DESCRIPTION entries to network modules 2020-06-20 21:33:57 -07:00
gre_demux.c gre: fix uninit-value in __iptunnel_pull_header 2020-03-08 21:25:37 -07:00
gre_offload.c net: gre: recompute gre csum for sctp over gre tunnels 2020-08-03 15:29:44 -07:00
icmp.c icmp6: support rfc 4884 2020-07-24 17:12:41 -07:00
igmp.c ip*_mc_gsfget(): lift copyout of struct group_filter into callers 2020-05-20 20:31:27 -04:00
inet_connection_sock.c net: refactor bind_bucket fastreuse into helper 2020-08-11 15:49:08 -07:00
inet_diag.c inet_diag: support for wider protocol numbers 2020-07-09 12:38:41 -07:00
inet_fragment.c inet: frags: re-introduce skb coalescing for local delivery 2019-08-08 15:55:10 -07:00
inet_hashtables.c net: initialize fastreuse on inet_inherit_port 2020-08-11 15:49:08 -07:00
inet_timewait_sock.c
inetpeer.c inetpeer: fix data-race in inet_putpeer / inet_putpeer 2019-11-07 16:15:56 -08:00
ip_forward.c ipv4: Revert removal of rt_uses_gateway 2019-09-20 18:23:33 -07:00
ip_fragment.c inet: frags: re-introduce skb coalescing for local delivery 2019-08-08 15:55:10 -07:00
ip_gre.c net: add a new ndo_tunnel_ioctl method 2020-05-19 15:45:11 -07:00
ip_input.c bpf: Add socket assign support 2020-03-30 13:45:04 -07:00
ip_options.c net/ipv4: merge ip_options_get and ip_options_get_from_user 2020-07-24 15:41:54 -07:00
ip_output.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2020-07-11 00:46:00 -07:00
ip_sockglue.c icmp: prepare rfc 4884 for ipv6 2020-07-24 17:12:41 -07:00
ip_tunnel.c ip_tunnel: fix use-after-free in ip_tunnel_lookup() 2020-06-18 20:12:34 -07:00
ip_tunnel_core.c Revert "ipv4: tunnel: fix compilation on ARCH=um" 2020-08-12 13:26:37 -07:00
ip_vti.c Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec-next 2020-07-30 14:39:31 -07:00
ipcomp.c ipcomp: assign if_id to child tunnel from parent tunnel 2020-07-09 12:55:37 +02:00
ipconfig.c Documentation: nfsroot.rst: Fix references to nfsroot.rst 2020-03-02 13:11:46 -07:00
ipip.c net: ipip: implement header_ops->parse_protocol for AF_PACKET 2020-06-30 12:29:39 -07:00
ipmr.c ipmr: Copy option to correct variable 2020-07-27 11:39:55 -07:00
ipmr_base.c net: fib_notifier: propagate extack down to the notifier block callback 2019-10-04 11:10:56 -07:00
Kconfig Replace HTTP links with HTTPS ones: IPv* 2020-07-06 13:23:03 -07:00
Makefile udp_tunnel: add central NIC RX port offload infrastructure 2020-07-10 13:54:00 -07:00
metrics.c
netfilter.c
netlink.c
nexthop.c nexthop: Fix fdb labeling for groups 2020-06-10 13:18:40 -07:00
ping.c ipv4: fill fl4_icmp_{type,code} in ping_v4_sendmsg 2020-07-07 15:26:37 -07:00
proc.c tcp: add SNMP counter for no. of duplicate segments reported by DSACK 2020-07-17 12:54:30 -07:00
protocol.c
raw.c net: pass a sockptr_t into ->setsockopt 2020-07-24 15:41:54 -07:00
raw_diag.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2020-03-12 22:34:48 -07:00
route.c ipv4: route: Ignore output interface in FIB lookup for PMTU route 2020-08-04 13:01:45 -07:00
syncookies.c tcp: fix build fong CONFIG_MPTCP=n 2020-08-01 11:46:29 -07:00
sysctl_net_ipv4.c tcp: correct read of TFO keys on big endian systems 2020-08-10 12:12:35 -07:00
tcp.c tcp: bpf: Add TCP_BPF_RTO_MIN for bpf_setsockopt 2020-08-24 14:35:00 -07:00
tcp_bbr.c tcp_bbr: improve arithmetic division in bbr_update_bw() 2020-01-21 10:45:49 +01:00
tcp_bic.c tcp: fix stretch ACK bugs in BIC 2020-03-16 18:26:54 -07:00
tcp_bpf.c net: sk_msg: Simplify sk_psock initialization 2020-08-21 15:16:11 -07:00
tcp_cdg.c
tcp_cong.c tcp: make sure listeners don't initialize congestion-control state 2020-07-09 13:07:45 -07:00
tcp_cubic.c tcp_cubic: fix spurious HYSTART_DELAY exit upon drop in min RTT 2020-06-25 16:08:47 -07:00
tcp_dctcp.c
tcp_dctcp.h
tcp_diag.c inet_diag: Move the INET_DIAG_REQ_BYTECODE nlattr to cb->data 2020-02-27 18:50:19 -08:00
tcp_fastopen.c bpf: tcp: Add bpf_skops_established() 2020-08-24 14:35:00 -07:00
tcp_highspeed.c Replace HTTP links with HTTPS ones: IPv* 2020-07-06 13:23:03 -07:00
tcp_htcp.c Replace HTTP links with HTTPS ones: IPv* 2020-07-06 13:23:03 -07:00
tcp_hybla.c
tcp_illinois.c
tcp_input.c bpf: tcp: Add bpf_skops_hdr_opt_len() and bpf_skops_write_hdr_opt() 2020-08-24 14:35:00 -07:00
tcp_ipv4.c bpf: tcp: Add bpf_skops_hdr_opt_len() and bpf_skops_write_hdr_opt() 2020-08-24 14:35:00 -07:00
tcp_lp.c
tcp_metrics.c net-tcp: Disable TCP ssthresh metrics cache by default 2019-12-09 20:17:48 -08:00
tcp_minisocks.c mptcp: add new sock flag to deal with join subflows 2020-05-15 12:30:13 -07:00
tcp_nv.c
tcp_offload.c
tcp_output.c bpf: tcp: Add bpf_skops_hdr_opt_len() and bpf_skops_write_hdr_opt() 2020-08-24 14:35:00 -07:00
tcp_rate.c
tcp_recovery.c
tcp_scalable.c tcp: fix stretch ACK bugs in Scalable 2020-03-16 18:26:54 -07:00
tcp_timer.c net: ipv4: kerneldoc fixes 2020-07-13 17:20:39 -07:00
tcp_ulp.c bpf: sockmap: Only check ULP for TCP sockets 2020-03-09 22:34:58 +01:00
tcp_vegas.c
tcp_vegas.h
tcp_veno.c Replace HTTP links with HTTPS ones: IPv* 2020-07-06 13:23:03 -07:00
tcp_westwood.c
tcp_yeah.c tcp: fix stretch ACK bugs in Yeah 2020-03-16 18:26:55 -07:00
tunnel4.c tunnel4: add cb_handler to struct xfrm_tunnel 2020-07-09 12:51:36 +02:00
udp.c udp, bpf: Ignore connections in reuseport group after BPF sk lookup 2020-07-31 02:00:48 +02:00
udp_bpf.c net: sk_msg: Simplify sk_psock initialization 2020-08-21 15:16:11 -07:00
udp_diag.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2020-03-12 22:34:48 -07:00
udp_impl.h net: pass a sockptr_t into ->setsockopt 2020-07-24 15:41:54 -07:00
udp_offload.c udp: initialize is_flist with 0 in udp_gro_receive 2020-03-30 10:35:03 -07:00
udp_tunnel_core.c udp_tunnel: add central NIC RX port offload infrastructure 2020-07-10 13:54:00 -07:00
udp_tunnel_nic.c udp_tunnel: add the ability to hard-code IANA VXLAN 2020-08-03 10:13:54 -07:00
udp_tunnel_stub.c udp_tunnel: add central NIC RX port offload infrastructure 2020-07-10 13:54:00 -07:00
udplite.c net/ipv4: remove compat_ip_{get,set}sockopt 2020-07-19 18:16:41 -07:00
xfrm4_input.c xfrm: state: remove extract_input indirection from xfrm_state_afinfo 2020-05-06 09:40:08 +02:00
xfrm4_output.c xfrm: fix unused variable warning if CONFIG_NETFILTER=n 2020-05-11 15:12:27 +02:00
xfrm4_policy.c net: add bool confirm_neigh parameter for dst_ops.update_pmtu 2019-12-24 22:28:54 -08:00
xfrm4_protocol.c xfrm: add route lookup to xfrm4_rcv_encap 2019-12-09 09:59:07 +01:00
xfrm4_state.c xfrm: remove output_finish indirection from xfrm_state_afinfo 2020-05-06 09:40:08 +02:00
xfrm4_tunnel.c