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- /* (C) 1999-2001 Paul `Rusty' Russell
- * (C) 2002-2004 Netfilter Core Team <coreteam@netfilter.org>
- * (C) 2002-2013 Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
- * (C) 2006-2012 Patrick McHardy <kaber@trash.net>
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- */
- #include <linux/types.h>
- #include <linux/timer.h>
- #include <linux/module.h>
- #include <linux/in.h>
- #include <linux/tcp.h>
- #include <linux/spinlock.h>
- #include <linux/skbuff.h>
- #include <linux/ipv6.h>
- #include <net/ip6_checksum.h>
- #include <asm/unaligned.h>
- #include <net/tcp.h>
- #include <linux/netfilter.h>
- #include <linux/netfilter_ipv4.h>
- #include <linux/netfilter_ipv6.h>
- #include <net/netfilter/nf_conntrack.h>
- #include <net/netfilter/nf_conntrack_l4proto.h>
- #include <net/netfilter/nf_conntrack_ecache.h>
- #include <net/netfilter/nf_conntrack_seqadj.h>
- #include <net/netfilter/nf_conntrack_synproxy.h>
- #include <net/netfilter/nf_log.h>
- #include <net/netfilter/ipv4/nf_conntrack_ipv4.h>
- #include <net/netfilter/ipv6/nf_conntrack_ipv6.h>
- /* "Be conservative in what you do,
- be liberal in what you accept from others."
- If it's non-zero, we mark only out of window RST segments as INVALID. */
- static int nf_ct_tcp_be_liberal __read_mostly = 0;
- /* If it is set to zero, we disable picking up already established
- connections. */
- static int nf_ct_tcp_loose __read_mostly = 1;
- /* Max number of the retransmitted packets without receiving an (acceptable)
- ACK from the destination. If this number is reached, a shorter timer
- will be started. */
- static int nf_ct_tcp_max_retrans __read_mostly = 3;
- /* FIXME: Examine ipfilter's timeouts and conntrack transitions more
- closely. They're more complex. --RR */
- static const char *const tcp_conntrack_names[] = {
- "NONE",
- "SYN_SENT",
- "SYN_RECV",
- "ESTABLISHED",
- "FIN_WAIT",
- "CLOSE_WAIT",
- "LAST_ACK",
- "TIME_WAIT",
- "CLOSE",
- "SYN_SENT2",
- };
- #define SECS * HZ
- #define MINS * 60 SECS
- #define HOURS * 60 MINS
- #define DAYS * 24 HOURS
- static unsigned int tcp_timeouts[TCP_CONNTRACK_TIMEOUT_MAX] __read_mostly = {
- [TCP_CONNTRACK_SYN_SENT] = 2 MINS,
- [TCP_CONNTRACK_SYN_RECV] = 60 SECS,
- [TCP_CONNTRACK_ESTABLISHED] = 5 DAYS,
- [TCP_CONNTRACK_FIN_WAIT] = 2 MINS,
- [TCP_CONNTRACK_CLOSE_WAIT] = 60 SECS,
- [TCP_CONNTRACK_LAST_ACK] = 30 SECS,
- [TCP_CONNTRACK_TIME_WAIT] = 2 MINS,
- [TCP_CONNTRACK_CLOSE] = 10 SECS,
- [TCP_CONNTRACK_SYN_SENT2] = 2 MINS,
- /* RFC1122 says the R2 limit should be at least 100 seconds.
- Linux uses 15 packets as limit, which corresponds
- to ~13-30min depending on RTO. */
- [TCP_CONNTRACK_RETRANS] = 5 MINS,
- [TCP_CONNTRACK_UNACK] = 5 MINS,
- };
- #define sNO TCP_CONNTRACK_NONE
- #define sSS TCP_CONNTRACK_SYN_SENT
- #define sSR TCP_CONNTRACK_SYN_RECV
- #define sES TCP_CONNTRACK_ESTABLISHED
- #define sFW TCP_CONNTRACK_FIN_WAIT
- #define sCW TCP_CONNTRACK_CLOSE_WAIT
- #define sLA TCP_CONNTRACK_LAST_ACK
- #define sTW TCP_CONNTRACK_TIME_WAIT
- #define sCL TCP_CONNTRACK_CLOSE
- #define sS2 TCP_CONNTRACK_SYN_SENT2
- #define sIV TCP_CONNTRACK_MAX
- #define sIG TCP_CONNTRACK_IGNORE
- /* What TCP flags are set from RST/SYN/FIN/ACK. */
- enum tcp_bit_set {
- TCP_SYN_SET,
- TCP_SYNACK_SET,
- TCP_FIN_SET,
- TCP_ACK_SET,
- TCP_RST_SET,
- TCP_NONE_SET,
- };
- /*
- * The TCP state transition table needs a few words...
- *
- * We are the man in the middle. All the packets go through us
- * but might get lost in transit to the destination.
- * It is assumed that the destinations can't receive segments
- * we haven't seen.
- *
- * The checked segment is in window, but our windows are *not*
- * equivalent with the ones of the sender/receiver. We always
- * try to guess the state of the current sender.
- *
- * The meaning of the states are:
- *
- * NONE: initial state
- * SYN_SENT: SYN-only packet seen
- * SYN_SENT2: SYN-only packet seen from reply dir, simultaneous open
- * SYN_RECV: SYN-ACK packet seen
- * ESTABLISHED: ACK packet seen
- * FIN_WAIT: FIN packet seen
- * CLOSE_WAIT: ACK seen (after FIN)
- * LAST_ACK: FIN seen (after FIN)
- * TIME_WAIT: last ACK seen
- * CLOSE: closed connection (RST)
- *
- * Packets marked as IGNORED (sIG):
- * if they may be either invalid or valid
- * and the receiver may send back a connection
- * closing RST or a SYN/ACK.
- *
- * Packets marked as INVALID (sIV):
- * if we regard them as truly invalid packets
- */
- static const u8 tcp_conntracks[2][6][TCP_CONNTRACK_MAX] = {
- {
- /* ORIGINAL */
- /* sNO, sSS, sSR, sES, sFW, sCW, sLA, sTW, sCL, sS2 */
- /*syn*/ { sSS, sSS, sIG, sIG, sIG, sIG, sIG, sSS, sSS, sS2 },
- /*
- * sNO -> sSS Initialize a new connection
- * sSS -> sSS Retransmitted SYN
- * sS2 -> sS2 Late retransmitted SYN
- * sSR -> sIG
- * sES -> sIG Error: SYNs in window outside the SYN_SENT state
- * are errors. Receiver will reply with RST
- * and close the connection.
- * Or we are not in sync and hold a dead connection.
- * sFW -> sIG
- * sCW -> sIG
- * sLA -> sIG
- * sTW -> sSS Reopened connection (RFC 1122).
- * sCL -> sSS
- */
- /* sNO, sSS, sSR, sES, sFW, sCW, sLA, sTW, sCL, sS2 */
- /*synack*/ { sIV, sIV, sSR, sIV, sIV, sIV, sIV, sIV, sIV, sSR },
- /*
- * sNO -> sIV Too late and no reason to do anything
- * sSS -> sIV Client can't send SYN and then SYN/ACK
- * sS2 -> sSR SYN/ACK sent to SYN2 in simultaneous open
- * sSR -> sSR Late retransmitted SYN/ACK in simultaneous open
- * sES -> sIV Invalid SYN/ACK packets sent by the client
- * sFW -> sIV
- * sCW -> sIV
- * sLA -> sIV
- * sTW -> sIV
- * sCL -> sIV
- */
- /* sNO, sSS, sSR, sES, sFW, sCW, sLA, sTW, sCL, sS2 */
- /*fin*/ { sIV, sIV, sFW, sFW, sLA, sLA, sLA, sTW, sCL, sIV },
- /*
- * sNO -> sIV Too late and no reason to do anything...
- * sSS -> sIV Client migth not send FIN in this state:
- * we enforce waiting for a SYN/ACK reply first.
- * sS2 -> sIV
- * sSR -> sFW Close started.
- * sES -> sFW
- * sFW -> sLA FIN seen in both directions, waiting for
- * the last ACK.
- * Migth be a retransmitted FIN as well...
- * sCW -> sLA
- * sLA -> sLA Retransmitted FIN. Remain in the same state.
- * sTW -> sTW
- * sCL -> sCL
- */
- /* sNO, sSS, sSR, sES, sFW, sCW, sLA, sTW, sCL, sS2 */
- /*ack*/ { sES, sIV, sES, sES, sCW, sCW, sTW, sTW, sCL, sIV },
- /*
- * sNO -> sES Assumed.
- * sSS -> sIV ACK is invalid: we haven't seen a SYN/ACK yet.
- * sS2 -> sIV
- * sSR -> sES Established state is reached.
- * sES -> sES :-)
- * sFW -> sCW Normal close request answered by ACK.
- * sCW -> sCW
- * sLA -> sTW Last ACK detected (RFC5961 challenged)
- * sTW -> sTW Retransmitted last ACK. Remain in the same state.
- * sCL -> sCL
- */
- /* sNO, sSS, sSR, sES, sFW, sCW, sLA, sTW, sCL, sS2 */
- /*rst*/ { sIV, sCL, sCL, sCL, sCL, sCL, sCL, sCL, sCL, sCL },
- /*none*/ { sIV, sIV, sIV, sIV, sIV, sIV, sIV, sIV, sIV, sIV }
- },
- {
- /* REPLY */
- /* sNO, sSS, sSR, sES, sFW, sCW, sLA, sTW, sCL, sS2 */
- /*syn*/ { sIV, sS2, sIV, sIV, sIV, sIV, sIV, sSS, sIV, sS2 },
- /*
- * sNO -> sIV Never reached.
- * sSS -> sS2 Simultaneous open
- * sS2 -> sS2 Retransmitted simultaneous SYN
- * sSR -> sIV Invalid SYN packets sent by the server
- * sES -> sIV
- * sFW -> sIV
- * sCW -> sIV
- * sLA -> sIV
- * sTW -> sSS Reopened connection, but server may have switched role
- * sCL -> sIV
- */
- /* sNO, sSS, sSR, sES, sFW, sCW, sLA, sTW, sCL, sS2 */
- /*synack*/ { sIV, sSR, sIG, sIG, sIG, sIG, sIG, sIG, sIG, sSR },
- /*
- * sSS -> sSR Standard open.
- * sS2 -> sSR Simultaneous open
- * sSR -> sIG Retransmitted SYN/ACK, ignore it.
- * sES -> sIG Late retransmitted SYN/ACK?
- * sFW -> sIG Might be SYN/ACK answering ignored SYN
- * sCW -> sIG
- * sLA -> sIG
- * sTW -> sIG
- * sCL -> sIG
- */
- /* sNO, sSS, sSR, sES, sFW, sCW, sLA, sTW, sCL, sS2 */
- /*fin*/ { sIV, sIV, sFW, sFW, sLA, sLA, sLA, sTW, sCL, sIV },
- /*
- * sSS -> sIV Server might not send FIN in this state.
- * sS2 -> sIV
- * sSR -> sFW Close started.
- * sES -> sFW
- * sFW -> sLA FIN seen in both directions.
- * sCW -> sLA
- * sLA -> sLA Retransmitted FIN.
- * sTW -> sTW
- * sCL -> sCL
- */
- /* sNO, sSS, sSR, sES, sFW, sCW, sLA, sTW, sCL, sS2 */
- /*ack*/ { sIV, sIG, sSR, sES, sCW, sCW, sTW, sTW, sCL, sIG },
- /*
- * sSS -> sIG Might be a half-open connection.
- * sS2 -> sIG
- * sSR -> sSR Might answer late resent SYN.
- * sES -> sES :-)
- * sFW -> sCW Normal close request answered by ACK.
- * sCW -> sCW
- * sLA -> sTW Last ACK detected (RFC5961 challenged)
- * sTW -> sTW Retransmitted last ACK.
- * sCL -> sCL
- */
- /* sNO, sSS, sSR, sES, sFW, sCW, sLA, sTW, sCL, sS2 */
- /*rst*/ { sIV, sCL, sCL, sCL, sCL, sCL, sCL, sCL, sCL, sCL },
- /*none*/ { sIV, sIV, sIV, sIV, sIV, sIV, sIV, sIV, sIV, sIV }
- }
- };
- static inline struct nf_tcp_net *tcp_pernet(struct net *net)
- {
- return &net->ct.nf_ct_proto.tcp;
- }
- static bool tcp_pkt_to_tuple(const struct sk_buff *skb, unsigned int dataoff,
- struct net *net, struct nf_conntrack_tuple *tuple)
- {
- const struct tcphdr *hp;
- struct tcphdr _hdr;
- /* Actually only need first 8 bytes. */
- hp = skb_header_pointer(skb, dataoff, 8, &_hdr);
- if (hp == NULL)
- return false;
- tuple->src.u.tcp.port = hp->source;
- tuple->dst.u.tcp.port = hp->dest;
- return true;
- }
- static bool tcp_invert_tuple(struct nf_conntrack_tuple *tuple,
- const struct nf_conntrack_tuple *orig)
- {
- tuple->src.u.tcp.port = orig->dst.u.tcp.port;
- tuple->dst.u.tcp.port = orig->src.u.tcp.port;
- return true;
- }
- /* Print out the per-protocol part of the tuple. */
- static void tcp_print_tuple(struct seq_file *s,
- const struct nf_conntrack_tuple *tuple)
- {
- seq_printf(s, "sport=%hu dport=%hu ",
- ntohs(tuple->src.u.tcp.port),
- ntohs(tuple->dst.u.tcp.port));
- }
- /* Print out the private part of the conntrack. */
- static void tcp_print_conntrack(struct seq_file *s, struct nf_conn *ct)
- {
- enum tcp_conntrack state;
- spin_lock_bh(&ct->lock);
- state = ct->proto.tcp.state;
- spin_unlock_bh(&ct->lock);
- seq_printf(s, "%s ", tcp_conntrack_names[state]);
- }
- static unsigned int get_conntrack_index(const struct tcphdr *tcph)
- {
- if (tcph->rst) return TCP_RST_SET;
- else if (tcph->syn) return (tcph->ack ? TCP_SYNACK_SET : TCP_SYN_SET);
- else if (tcph->fin) return TCP_FIN_SET;
- else if (tcph->ack) return TCP_ACK_SET;
- else return TCP_NONE_SET;
- }
- /* TCP connection tracking based on 'Real Stateful TCP Packet Filtering
- in IP Filter' by Guido van Rooij.
- http://www.sane.nl/events/sane2000/papers.html
- http://www.darkart.com/mirrors/www.obfuscation.org/ipf/
- The boundaries and the conditions are changed according to RFC793:
- the packet must intersect the window (i.e. segments may be
- after the right or before the left edge) and thus receivers may ACK
- segments after the right edge of the window.
- td_maxend = max(sack + max(win,1)) seen in reply packets
- td_maxwin = max(max(win, 1)) + (sack - ack) seen in sent packets
- td_maxwin += seq + len - sender.td_maxend
- if seq + len > sender.td_maxend
- td_end = max(seq + len) seen in sent packets
- I. Upper bound for valid data: seq <= sender.td_maxend
- II. Lower bound for valid data: seq + len >= sender.td_end - receiver.td_maxwin
- III. Upper bound for valid (s)ack: sack <= receiver.td_end
- IV. Lower bound for valid (s)ack: sack >= receiver.td_end - MAXACKWINDOW
- where sack is the highest right edge of sack block found in the packet
- or ack in the case of packet without SACK option.
- The upper bound limit for a valid (s)ack is not ignored -
- we doesn't have to deal with fragments.
- */
- static inline __u32 segment_seq_plus_len(__u32 seq,
- size_t len,
- unsigned int dataoff,
- const struct tcphdr *tcph)
- {
- /* XXX Should I use payload length field in IP/IPv6 header ?
- * - YK */
- return (seq + len - dataoff - tcph->doff*4
- + (tcph->syn ? 1 : 0) + (tcph->fin ? 1 : 0));
- }
- /* Fixme: what about big packets? */
- #define MAXACKWINCONST 66000
- #define MAXACKWINDOW(sender) \
- ((sender)->td_maxwin > MAXACKWINCONST ? (sender)->td_maxwin \
- : MAXACKWINCONST)
- /*
- * Simplified tcp_parse_options routine from tcp_input.c
- */
- static void tcp_options(const struct sk_buff *skb,
- unsigned int dataoff,
- const struct tcphdr *tcph,
- struct ip_ct_tcp_state *state)
- {
- unsigned char buff[(15 * 4) - sizeof(struct tcphdr)];
- const unsigned char *ptr;
- int length = (tcph->doff*4) - sizeof(struct tcphdr);
- if (!length)
- return;
- ptr = skb_header_pointer(skb, dataoff + sizeof(struct tcphdr),
- length, buff);
- BUG_ON(ptr == NULL);
- state->td_scale =
- state->flags = 0;
- while (length > 0) {
- int opcode=*ptr++;
- int opsize;
- switch (opcode) {
- case TCPOPT_EOL:
- return;
- case TCPOPT_NOP: /* Ref: RFC 793 section 3.1 */
- length--;
- continue;
- default:
- if (length < 2)
- return;
- opsize=*ptr++;
- if (opsize < 2) /* "silly options" */
- return;
- if (opsize > length)
- return; /* don't parse partial options */
- if (opcode == TCPOPT_SACK_PERM
- && opsize == TCPOLEN_SACK_PERM)
- state->flags |= IP_CT_TCP_FLAG_SACK_PERM;
- else if (opcode == TCPOPT_WINDOW
- && opsize == TCPOLEN_WINDOW) {
- state->td_scale = *(u_int8_t *)ptr;
- if (state->td_scale > 14) {
- /* See RFC1323 */
- state->td_scale = 14;
- }
- state->flags |=
- IP_CT_TCP_FLAG_WINDOW_SCALE;
- }
- ptr += opsize - 2;
- length -= opsize;
- }
- }
- }
- static void tcp_sack(const struct sk_buff *skb, unsigned int dataoff,
- const struct tcphdr *tcph, __u32 *sack)
- {
- unsigned char buff[(15 * 4) - sizeof(struct tcphdr)];
- const unsigned char *ptr;
- int length = (tcph->doff*4) - sizeof(struct tcphdr);
- __u32 tmp;
- if (!length)
- return;
- ptr = skb_header_pointer(skb, dataoff + sizeof(struct tcphdr),
- length, buff);
- BUG_ON(ptr == NULL);
- /* Fast path for timestamp-only option */
- if (length == TCPOLEN_TSTAMP_ALIGNED
- && *(__be32 *)ptr == htonl((TCPOPT_NOP << 24)
- | (TCPOPT_NOP << 16)
- | (TCPOPT_TIMESTAMP << 8)
- | TCPOLEN_TIMESTAMP))
- return;
- while (length > 0) {
- int opcode = *ptr++;
- int opsize, i;
- switch (opcode) {
- case TCPOPT_EOL:
- return;
- case TCPOPT_NOP: /* Ref: RFC 793 section 3.1 */
- length--;
- continue;
- default:
- if (length < 2)
- return;
- opsize = *ptr++;
- if (opsize < 2) /* "silly options" */
- return;
- if (opsize > length)
- return; /* don't parse partial options */
- if (opcode == TCPOPT_SACK
- && opsize >= (TCPOLEN_SACK_BASE
- + TCPOLEN_SACK_PERBLOCK)
- && !((opsize - TCPOLEN_SACK_BASE)
- % TCPOLEN_SACK_PERBLOCK)) {
- for (i = 0;
- i < (opsize - TCPOLEN_SACK_BASE);
- i += TCPOLEN_SACK_PERBLOCK) {
- tmp = get_unaligned_be32((__be32 *)(ptr+i)+1);
- if (after(tmp, *sack))
- *sack = tmp;
- }
- return;
- }
- ptr += opsize - 2;
- length -= opsize;
- }
- }
- }
- static bool tcp_in_window(const struct nf_conn *ct,
- struct ip_ct_tcp *state,
- enum ip_conntrack_dir dir,
- unsigned int index,
- const struct sk_buff *skb,
- unsigned int dataoff,
- const struct tcphdr *tcph,
- u_int8_t pf)
- {
- struct net *net = nf_ct_net(ct);
- struct nf_tcp_net *tn = tcp_pernet(net);
- struct ip_ct_tcp_state *sender = &state->seen[dir];
- struct ip_ct_tcp_state *receiver = &state->seen[!dir];
- const struct nf_conntrack_tuple *tuple = &ct->tuplehash[dir].tuple;
- __u32 seq, ack, sack, end, win, swin;
- s32 receiver_offset;
- bool res, in_recv_win;
- /*
- * Get the required data from the packet.
- */
- seq = ntohl(tcph->seq);
- ack = sack = ntohl(tcph->ack_seq);
- win = ntohs(tcph->window);
- end = segment_seq_plus_len(seq, skb->len, dataoff, tcph);
- if (receiver->flags & IP_CT_TCP_FLAG_SACK_PERM)
- tcp_sack(skb, dataoff, tcph, &sack);
- /* Take into account NAT sequence number mangling */
- receiver_offset = nf_ct_seq_offset(ct, !dir, ack - 1);
- ack -= receiver_offset;
- sack -= receiver_offset;
- pr_debug("tcp_in_window: START\n");
- pr_debug("tcp_in_window: ");
- nf_ct_dump_tuple(tuple);
- pr_debug("seq=%u ack=%u+(%d) sack=%u+(%d) win=%u end=%u\n",
- seq, ack, receiver_offset, sack, receiver_offset, win, end);
- pr_debug("tcp_in_window: sender end=%u maxend=%u maxwin=%u scale=%i "
- "receiver end=%u maxend=%u maxwin=%u scale=%i\n",
- sender->td_end, sender->td_maxend, sender->td_maxwin,
- sender->td_scale,
- receiver->td_end, receiver->td_maxend, receiver->td_maxwin,
- receiver->td_scale);
- if (sender->td_maxwin == 0) {
- /*
- * Initialize sender data.
- */
- if (tcph->syn) {
- /*
- * SYN-ACK in reply to a SYN
- * or SYN from reply direction in simultaneous open.
- */
- sender->td_end =
- sender->td_maxend = end;
- sender->td_maxwin = (win == 0 ? 1 : win);
- tcp_options(skb, dataoff, tcph, sender);
- /*
- * RFC 1323:
- * Both sides must send the Window Scale option
- * to enable window scaling in either direction.
- */
- if (!(sender->flags & IP_CT_TCP_FLAG_WINDOW_SCALE
- && receiver->flags & IP_CT_TCP_FLAG_WINDOW_SCALE))
- sender->td_scale =
- receiver->td_scale = 0;
- if (!tcph->ack)
- /* Simultaneous open */
- return true;
- } else {
- /*
- * We are in the middle of a connection,
- * its history is lost for us.
- * Let's try to use the data from the packet.
- */
- sender->td_end = end;
- swin = win << sender->td_scale;
- sender->td_maxwin = (swin == 0 ? 1 : swin);
- sender->td_maxend = end + sender->td_maxwin;
- /*
- * We haven't seen traffic in the other direction yet
- * but we have to tweak window tracking to pass III
- * and IV until that happens.
- */
- if (receiver->td_maxwin == 0)
- receiver->td_end = receiver->td_maxend = sack;
- }
- } else if (((state->state == TCP_CONNTRACK_SYN_SENT
- && dir == IP_CT_DIR_ORIGINAL)
- || (state->state == TCP_CONNTRACK_SYN_RECV
- && dir == IP_CT_DIR_REPLY))
- && after(end, sender->td_end)) {
- /*
- * RFC 793: "if a TCP is reinitialized ... then it need
- * not wait at all; it must only be sure to use sequence
- * numbers larger than those recently used."
- */
- sender->td_end =
- sender->td_maxend = end;
- sender->td_maxwin = (win == 0 ? 1 : win);
- tcp_options(skb, dataoff, tcph, sender);
- }
- if (!(tcph->ack)) {
- /*
- * If there is no ACK, just pretend it was set and OK.
- */
- ack = sack = receiver->td_end;
- } else if (((tcp_flag_word(tcph) & (TCP_FLAG_ACK|TCP_FLAG_RST)) ==
- (TCP_FLAG_ACK|TCP_FLAG_RST))
- && (ack == 0)) {
- /*
- * Broken TCP stacks, that set ACK in RST packets as well
- * with zero ack value.
- */
- ack = sack = receiver->td_end;
- }
- if (tcph->rst && seq == 0 && state->state == TCP_CONNTRACK_SYN_SENT)
- /*
- * RST sent answering SYN.
- */
- seq = end = sender->td_end;
- pr_debug("tcp_in_window: ");
- nf_ct_dump_tuple(tuple);
- pr_debug("seq=%u ack=%u+(%d) sack=%u+(%d) win=%u end=%u\n",
- seq, ack, receiver_offset, sack, receiver_offset, win, end);
- pr_debug("tcp_in_window: sender end=%u maxend=%u maxwin=%u scale=%i "
- "receiver end=%u maxend=%u maxwin=%u scale=%i\n",
- sender->td_end, sender->td_maxend, sender->td_maxwin,
- sender->td_scale,
- receiver->td_end, receiver->td_maxend, receiver->td_maxwin,
- receiver->td_scale);
- /* Is the ending sequence in the receive window (if available)? */
- in_recv_win = !receiver->td_maxwin ||
- after(end, sender->td_end - receiver->td_maxwin - 1);
- pr_debug("tcp_in_window: I=%i II=%i III=%i IV=%i\n",
- before(seq, sender->td_maxend + 1),
- (in_recv_win ? 1 : 0),
- before(sack, receiver->td_end + 1),
- after(sack, receiver->td_end - MAXACKWINDOW(sender) - 1));
- if (before(seq, sender->td_maxend + 1) &&
- in_recv_win &&
- before(sack, receiver->td_end + 1) &&
- after(sack, receiver->td_end - MAXACKWINDOW(sender) - 1)) {
- /*
- * Take into account window scaling (RFC 1323).
- */
- if (!tcph->syn)
- win <<= sender->td_scale;
- /*
- * Update sender data.
- */
- swin = win + (sack - ack);
- if (sender->td_maxwin < swin)
- sender->td_maxwin = swin;
- if (after(end, sender->td_end)) {
- sender->td_end = end;
- sender->flags |= IP_CT_TCP_FLAG_DATA_UNACKNOWLEDGED;
- }
- if (tcph->ack) {
- if (!(sender->flags & IP_CT_TCP_FLAG_MAXACK_SET)) {
- sender->td_maxack = ack;
- sender->flags |= IP_CT_TCP_FLAG_MAXACK_SET;
- } else if (after(ack, sender->td_maxack))
- sender->td_maxack = ack;
- }
- /*
- * Update receiver data.
- */
- if (receiver->td_maxwin != 0 && after(end, sender->td_maxend))
- receiver->td_maxwin += end - sender->td_maxend;
- if (after(sack + win, receiver->td_maxend - 1)) {
- receiver->td_maxend = sack + win;
- if (win == 0)
- receiver->td_maxend++;
- }
- if (ack == receiver->td_end)
- receiver->flags &= ~IP_CT_TCP_FLAG_DATA_UNACKNOWLEDGED;
- /*
- * Check retransmissions.
- */
- if (index == TCP_ACK_SET) {
- if (state->last_dir == dir
- && state->last_seq == seq
- && state->last_ack == ack
- && state->last_end == end
- && state->last_win == win)
- state->retrans++;
- else {
- state->last_dir = dir;
- state->last_seq = seq;
- state->last_ack = ack;
- state->last_end = end;
- state->last_win = win;
- state->retrans = 0;
- }
- }
- res = true;
- } else {
- res = false;
- if (sender->flags & IP_CT_TCP_FLAG_BE_LIBERAL ||
- tn->tcp_be_liberal)
- res = true;
- if (!res && LOG_INVALID(net, IPPROTO_TCP))
- nf_log_packet(net, pf, 0, skb, NULL, NULL, NULL,
- "nf_ct_tcp: %s ",
- before(seq, sender->td_maxend + 1) ?
- in_recv_win ?
- before(sack, receiver->td_end + 1) ?
- after(sack, receiver->td_end - MAXACKWINDOW(sender) - 1) ? "BUG"
- : "ACK is under the lower bound (possible overly delayed ACK)"
- : "ACK is over the upper bound (ACKed data not seen yet)"
- : "SEQ is under the lower bound (already ACKed data retransmitted)"
- : "SEQ is over the upper bound (over the window of the receiver)");
- }
- pr_debug("tcp_in_window: res=%u sender end=%u maxend=%u maxwin=%u "
- "receiver end=%u maxend=%u maxwin=%u\n",
- res, sender->td_end, sender->td_maxend, sender->td_maxwin,
- receiver->td_end, receiver->td_maxend, receiver->td_maxwin);
- return res;
- }
- /* table of valid flag combinations - PUSH, ECE and CWR are always valid */
- static const u8 tcp_valid_flags[(TCPHDR_FIN|TCPHDR_SYN|TCPHDR_RST|TCPHDR_ACK|
- TCPHDR_URG) + 1] =
- {
- [TCPHDR_SYN] = 1,
- [TCPHDR_SYN|TCPHDR_URG] = 1,
- [TCPHDR_SYN|TCPHDR_ACK] = 1,
- [TCPHDR_RST] = 1,
- [TCPHDR_RST|TCPHDR_ACK] = 1,
- [TCPHDR_FIN|TCPHDR_ACK] = 1,
- [TCPHDR_FIN|TCPHDR_ACK|TCPHDR_URG] = 1,
- [TCPHDR_ACK] = 1,
- [TCPHDR_ACK|TCPHDR_URG] = 1,
- };
- /* Protect conntrack agaist broken packets. Code taken from ipt_unclean.c. */
- static int tcp_error(struct net *net, struct nf_conn *tmpl,
- struct sk_buff *skb,
- unsigned int dataoff,
- enum ip_conntrack_info *ctinfo,
- u_int8_t pf,
- unsigned int hooknum)
- {
- const struct tcphdr *th;
- struct tcphdr _tcph;
- unsigned int tcplen = skb->len - dataoff;
- u_int8_t tcpflags;
- /* Smaller that minimal TCP header? */
- th = skb_header_pointer(skb, dataoff, sizeof(_tcph), &_tcph);
- if (th == NULL) {
- if (LOG_INVALID(net, IPPROTO_TCP))
- nf_log_packet(net, pf, 0, skb, NULL, NULL, NULL,
- "nf_ct_tcp: short packet ");
- return -NF_ACCEPT;
- }
- /* Not whole TCP header or malformed packet */
- if (th->doff*4 < sizeof(struct tcphdr) || tcplen < th->doff*4) {
- if (LOG_INVALID(net, IPPROTO_TCP))
- nf_log_packet(net, pf, 0, skb, NULL, NULL, NULL,
- "nf_ct_tcp: truncated/malformed packet ");
- return -NF_ACCEPT;
- }
- /* Checksum invalid? Ignore.
- * We skip checking packets on the outgoing path
- * because the checksum is assumed to be correct.
- */
- /* FIXME: Source route IP option packets --RR */
- if (net->ct.sysctl_checksum && hooknum == NF_INET_PRE_ROUTING &&
- nf_checksum(skb, hooknum, dataoff, IPPROTO_TCP, pf)) {
- if (LOG_INVALID(net, IPPROTO_TCP))
- nf_log_packet(net, pf, 0, skb, NULL, NULL, NULL,
- "nf_ct_tcp: bad TCP checksum ");
- return -NF_ACCEPT;
- }
- /* Check TCP flags. */
- tcpflags = (tcp_flag_byte(th) & ~(TCPHDR_ECE|TCPHDR_CWR|TCPHDR_PSH));
- if (!tcp_valid_flags[tcpflags]) {
- if (LOG_INVALID(net, IPPROTO_TCP))
- nf_log_packet(net, pf, 0, skb, NULL, NULL, NULL,
- "nf_ct_tcp: invalid TCP flag combination ");
- return -NF_ACCEPT;
- }
- return NF_ACCEPT;
- }
- static unsigned int *tcp_get_timeouts(struct net *net)
- {
- return tcp_pernet(net)->timeouts;
- }
- /* Returns verdict for packet, or -1 for invalid. */
- static int tcp_packet(struct nf_conn *ct,
- const struct sk_buff *skb,
- unsigned int dataoff,
- enum ip_conntrack_info ctinfo,
- u_int8_t pf,
- unsigned int hooknum,
- unsigned int *timeouts)
- {
- struct net *net = nf_ct_net(ct);
- struct nf_tcp_net *tn = tcp_pernet(net);
- struct nf_conntrack_tuple *tuple;
- enum tcp_conntrack new_state, old_state;
- enum ip_conntrack_dir dir;
- const struct tcphdr *th;
- struct tcphdr _tcph;
- unsigned long timeout;
- unsigned int index;
- th = skb_header_pointer(skb, dataoff, sizeof(_tcph), &_tcph);
- BUG_ON(th == NULL);
- spin_lock_bh(&ct->lock);
- old_state = ct->proto.tcp.state;
- dir = CTINFO2DIR(ctinfo);
- index = get_conntrack_index(th);
- new_state = tcp_conntracks[dir][index][old_state];
- tuple = &ct->tuplehash[dir].tuple;
- switch (new_state) {
- case TCP_CONNTRACK_SYN_SENT:
- if (old_state < TCP_CONNTRACK_TIME_WAIT)
- break;
- /* RFC 1122: "When a connection is closed actively,
- * it MUST linger in TIME-WAIT state for a time 2xMSL
- * (Maximum Segment Lifetime). However, it MAY accept
- * a new SYN from the remote TCP to reopen the connection
- * directly from TIME-WAIT state, if..."
- * We ignore the conditions because we are in the
- * TIME-WAIT state anyway.
- *
- * Handle aborted connections: we and the server
- * think there is an existing connection but the client
- * aborts it and starts a new one.
- */
- if (((ct->proto.tcp.seen[dir].flags
- | ct->proto.tcp.seen[!dir].flags)
- & IP_CT_TCP_FLAG_CLOSE_INIT)
- || (ct->proto.tcp.last_dir == dir
- && ct->proto.tcp.last_index == TCP_RST_SET)) {
- /* Attempt to reopen a closed/aborted connection.
- * Delete this connection and look up again. */
- spin_unlock_bh(&ct->lock);
- /* Only repeat if we can actually remove the timer.
- * Destruction may already be in progress in process
- * context and we must give it a chance to terminate.
- */
- if (nf_ct_kill(ct))
- return -NF_REPEAT;
- return NF_DROP;
- }
- /* Fall through */
- case TCP_CONNTRACK_IGNORE:
- /* Ignored packets:
- *
- * Our connection entry may be out of sync, so ignore
- * packets which may signal the real connection between
- * the client and the server.
- *
- * a) SYN in ORIGINAL
- * b) SYN/ACK in REPLY
- * c) ACK in reply direction after initial SYN in original.
- *
- * If the ignored packet is invalid, the receiver will send
- * a RST we'll catch below.
- */
- if (index == TCP_SYNACK_SET
- && ct->proto.tcp.last_index == TCP_SYN_SET
- && ct->proto.tcp.last_dir != dir
- && ntohl(th->ack_seq) == ct->proto.tcp.last_end) {
- /* b) This SYN/ACK acknowledges a SYN that we earlier
- * ignored as invalid. This means that the client and
- * the server are both in sync, while the firewall is
- * not. We get in sync from the previously annotated
- * values.
- */
- old_state = TCP_CONNTRACK_SYN_SENT;
- new_state = TCP_CONNTRACK_SYN_RECV;
- ct->proto.tcp.seen[ct->proto.tcp.last_dir].td_end =
- ct->proto.tcp.last_end;
- ct->proto.tcp.seen[ct->proto.tcp.last_dir].td_maxend =
- ct->proto.tcp.last_end;
- ct->proto.tcp.seen[ct->proto.tcp.last_dir].td_maxwin =
- ct->proto.tcp.last_win == 0 ?
- 1 : ct->proto.tcp.last_win;
- ct->proto.tcp.seen[ct->proto.tcp.last_dir].td_scale =
- ct->proto.tcp.last_wscale;
- ct->proto.tcp.last_flags &= ~IP_CT_EXP_CHALLENGE_ACK;
- ct->proto.tcp.seen[ct->proto.tcp.last_dir].flags =
- ct->proto.tcp.last_flags;
- memset(&ct->proto.tcp.seen[dir], 0,
- sizeof(struct ip_ct_tcp_state));
- break;
- }
- ct->proto.tcp.last_index = index;
- ct->proto.tcp.last_dir = dir;
- ct->proto.tcp.last_seq = ntohl(th->seq);
- ct->proto.tcp.last_end =
- segment_seq_plus_len(ntohl(th->seq), skb->len, dataoff, th);
- ct->proto.tcp.last_win = ntohs(th->window);
- /* a) This is a SYN in ORIGINAL. The client and the server
- * may be in sync but we are not. In that case, we annotate
- * the TCP options and let the packet go through. If it is a
- * valid SYN packet, the server will reply with a SYN/ACK, and
- * then we'll get in sync. Otherwise, the server potentially
- * responds with a challenge ACK if implementing RFC5961.
- */
- if (index == TCP_SYN_SET && dir == IP_CT_DIR_ORIGINAL) {
- struct ip_ct_tcp_state seen = {};
- ct->proto.tcp.last_flags =
- ct->proto.tcp.last_wscale = 0;
- tcp_options(skb, dataoff, th, &seen);
- if (seen.flags & IP_CT_TCP_FLAG_WINDOW_SCALE) {
- ct->proto.tcp.last_flags |=
- IP_CT_TCP_FLAG_WINDOW_SCALE;
- ct->proto.tcp.last_wscale = seen.td_scale;
- }
- if (seen.flags & IP_CT_TCP_FLAG_SACK_PERM) {
- ct->proto.tcp.last_flags |=
- IP_CT_TCP_FLAG_SACK_PERM;
- }
- /* Mark the potential for RFC5961 challenge ACK,
- * this pose a special problem for LAST_ACK state
- * as ACK is intrepretated as ACKing last FIN.
- */
- if (old_state == TCP_CONNTRACK_LAST_ACK)
- ct->proto.tcp.last_flags |=
- IP_CT_EXP_CHALLENGE_ACK;
- }
- spin_unlock_bh(&ct->lock);
- if (LOG_INVALID(net, IPPROTO_TCP))
- nf_log_packet(net, pf, 0, skb, NULL, NULL, NULL,
- "nf_ct_tcp: invalid packet ignored in "
- "state %s ", tcp_conntrack_names[old_state]);
- return NF_ACCEPT;
- case TCP_CONNTRACK_MAX:
- /* Special case for SYN proxy: when the SYN to the server or
- * the SYN/ACK from the server is lost, the client may transmit
- * a keep-alive packet while in SYN_SENT state. This needs to
- * be associated with the original conntrack entry in order to
- * generate a new SYN with the correct sequence number.
- */
- if (nfct_synproxy(ct) && old_state == TCP_CONNTRACK_SYN_SENT &&
- index == TCP_ACK_SET && dir == IP_CT_DIR_ORIGINAL &&
- ct->proto.tcp.last_dir == IP_CT_DIR_ORIGINAL &&
- ct->proto.tcp.seen[dir].td_end - 1 == ntohl(th->seq)) {
- pr_debug("nf_ct_tcp: SYN proxy client keep alive\n");
- spin_unlock_bh(&ct->lock);
- return NF_ACCEPT;
- }
- /* Invalid packet */
- pr_debug("nf_ct_tcp: Invalid dir=%i index=%u ostate=%u\n",
- dir, get_conntrack_index(th), old_state);
- spin_unlock_bh(&ct->lock);
- if (LOG_INVALID(net, IPPROTO_TCP))
- nf_log_packet(net, pf, 0, skb, NULL, NULL, NULL,
- "nf_ct_tcp: invalid state ");
- return -NF_ACCEPT;
- case TCP_CONNTRACK_TIME_WAIT:
- /* RFC5961 compliance cause stack to send "challenge-ACK"
- * e.g. in response to spurious SYNs. Conntrack MUST
- * not believe this ACK is acking last FIN.
- */
- if (old_state == TCP_CONNTRACK_LAST_ACK &&
- index == TCP_ACK_SET &&
- ct->proto.tcp.last_dir != dir &&
- ct->proto.tcp.last_index == TCP_SYN_SET &&
- (ct->proto.tcp.last_flags & IP_CT_EXP_CHALLENGE_ACK)) {
- /* Detected RFC5961 challenge ACK */
- ct->proto.tcp.last_flags &= ~IP_CT_EXP_CHALLENGE_ACK;
- spin_unlock_bh(&ct->lock);
- if (LOG_INVALID(net, IPPROTO_TCP))
- nf_log_packet(net, pf, 0, skb, NULL, NULL, NULL,
- "nf_ct_tcp: challenge-ACK ignored ");
- return NF_ACCEPT; /* Don't change state */
- }
- break;
- case TCP_CONNTRACK_CLOSE:
- if (index == TCP_RST_SET
- && (ct->proto.tcp.seen[!dir].flags & IP_CT_TCP_FLAG_MAXACK_SET)
- && before(ntohl(th->seq), ct->proto.tcp.seen[!dir].td_maxack)) {
- /* Invalid RST */
- spin_unlock_bh(&ct->lock);
- if (LOG_INVALID(net, IPPROTO_TCP))
- nf_log_packet(net, pf, 0, skb, NULL, NULL,
- NULL, "nf_ct_tcp: invalid RST ");
- return -NF_ACCEPT;
- }
- if (index == TCP_RST_SET
- && ((test_bit(IPS_SEEN_REPLY_BIT, &ct->status)
- && ct->proto.tcp.last_index == TCP_SYN_SET)
- || (!test_bit(IPS_ASSURED_BIT, &ct->status)
- && ct->proto.tcp.last_index == TCP_ACK_SET))
- && ntohl(th->ack_seq) == ct->proto.tcp.last_end) {
- /* RST sent to invalid SYN or ACK we had let through
- * at a) and c) above:
- *
- * a) SYN was in window then
- * c) we hold a half-open connection.
- *
- * Delete our connection entry.
- * We skip window checking, because packet might ACK
- * segments we ignored. */
- goto in_window;
- }
- /* Just fall through */
- default:
- /* Keep compilers happy. */
- break;
- }
- if (!tcp_in_window(ct, &ct->proto.tcp, dir, index,
- skb, dataoff, th, pf)) {
- spin_unlock_bh(&ct->lock);
- return -NF_ACCEPT;
- }
- in_window:
- /* From now on we have got in-window packets */
- ct->proto.tcp.last_index = index;
- ct->proto.tcp.last_dir = dir;
- pr_debug("tcp_conntracks: ");
- nf_ct_dump_tuple(tuple);
- pr_debug("syn=%i ack=%i fin=%i rst=%i old=%i new=%i\n",
- (th->syn ? 1 : 0), (th->ack ? 1 : 0),
- (th->fin ? 1 : 0), (th->rst ? 1 : 0),
- old_state, new_state);
- ct->proto.tcp.state = new_state;
- if (old_state != new_state
- && new_state == TCP_CONNTRACK_FIN_WAIT)
- ct->proto.tcp.seen[dir].flags |= IP_CT_TCP_FLAG_CLOSE_INIT;
- if (ct->proto.tcp.retrans >= tn->tcp_max_retrans &&
- timeouts[new_state] > timeouts[TCP_CONNTRACK_RETRANS])
- timeout = timeouts[TCP_CONNTRACK_RETRANS];
- else if ((ct->proto.tcp.seen[0].flags | ct->proto.tcp.seen[1].flags) &
- IP_CT_TCP_FLAG_DATA_UNACKNOWLEDGED &&
- timeouts[new_state] > timeouts[TCP_CONNTRACK_UNACK])
- timeout = timeouts[TCP_CONNTRACK_UNACK];
- else
- timeout = timeouts[new_state];
- spin_unlock_bh(&ct->lock);
- if (new_state != old_state)
- nf_conntrack_event_cache(IPCT_PROTOINFO, ct);
- if (!test_bit(IPS_SEEN_REPLY_BIT, &ct->status)) {
- /* If only reply is a RST, we can consider ourselves not to
- have an established connection: this is a fairly common
- problem case, so we can delete the conntrack
- immediately. --RR */
- if (th->rst) {
- nf_ct_kill_acct(ct, ctinfo, skb);
- return NF_ACCEPT;
- }
- /* ESTABLISHED without SEEN_REPLY, i.e. mid-connection
- * pickup with loose=1. Avoid large ESTABLISHED timeout.
- */
- if (new_state == TCP_CONNTRACK_ESTABLISHED &&
- timeout > timeouts[TCP_CONNTRACK_UNACK])
- timeout = timeouts[TCP_CONNTRACK_UNACK];
- } else if (!test_bit(IPS_ASSURED_BIT, &ct->status)
- && (old_state == TCP_CONNTRACK_SYN_RECV
- || old_state == TCP_CONNTRACK_ESTABLISHED)
- && new_state == TCP_CONNTRACK_ESTABLISHED) {
- /* Set ASSURED if we see see valid ack in ESTABLISHED
- after SYN_RECV or a valid answer for a picked up
- connection. */
- set_bit(IPS_ASSURED_BIT, &ct->status);
- nf_conntrack_event_cache(IPCT_ASSURED, ct);
- }
- nf_ct_refresh_acct(ct, ctinfo, skb, timeout);
- return NF_ACCEPT;
- }
- /* Called when a new connection for this protocol found. */
- static bool tcp_new(struct nf_conn *ct, const struct sk_buff *skb,
- unsigned int dataoff, unsigned int *timeouts)
- {
- enum tcp_conntrack new_state;
- const struct tcphdr *th;
- struct tcphdr _tcph;
- struct net *net = nf_ct_net(ct);
- struct nf_tcp_net *tn = tcp_pernet(net);
- const struct ip_ct_tcp_state *sender = &ct->proto.tcp.seen[0];
- const struct ip_ct_tcp_state *receiver = &ct->proto.tcp.seen[1];
- th = skb_header_pointer(skb, dataoff, sizeof(_tcph), &_tcph);
- BUG_ON(th == NULL);
- /* Don't need lock here: this conntrack not in circulation yet */
- new_state = tcp_conntracks[0][get_conntrack_index(th)][TCP_CONNTRACK_NONE];
- /* Invalid: delete conntrack */
- if (new_state >= TCP_CONNTRACK_MAX) {
- pr_debug("nf_ct_tcp: invalid new deleting.\n");
- return false;
- }
- if (new_state == TCP_CONNTRACK_SYN_SENT) {
- memset(&ct->proto.tcp, 0, sizeof(ct->proto.tcp));
- /* SYN packet */
- ct->proto.tcp.seen[0].td_end =
- segment_seq_plus_len(ntohl(th->seq), skb->len,
- dataoff, th);
- ct->proto.tcp.seen[0].td_maxwin = ntohs(th->window);
- if (ct->proto.tcp.seen[0].td_maxwin == 0)
- ct->proto.tcp.seen[0].td_maxwin = 1;
- ct->proto.tcp.seen[0].td_maxend =
- ct->proto.tcp.seen[0].td_end;
- tcp_options(skb, dataoff, th, &ct->proto.tcp.seen[0]);
- } else if (tn->tcp_loose == 0) {
- /* Don't try to pick up connections. */
- return false;
- } else {
- memset(&ct->proto.tcp, 0, sizeof(ct->proto.tcp));
- /*
- * We are in the middle of a connection,
- * its history is lost for us.
- * Let's try to use the data from the packet.
- */
- ct->proto.tcp.seen[0].td_end =
- segment_seq_plus_len(ntohl(th->seq), skb->len,
- dataoff, th);
- ct->proto.tcp.seen[0].td_maxwin = ntohs(th->window);
- if (ct->proto.tcp.seen[0].td_maxwin == 0)
- ct->proto.tcp.seen[0].td_maxwin = 1;
- ct->proto.tcp.seen[0].td_maxend =
- ct->proto.tcp.seen[0].td_end +
- ct->proto.tcp.seen[0].td_maxwin;
- /* We assume SACK and liberal window checking to handle
- * window scaling */
- ct->proto.tcp.seen[0].flags =
- ct->proto.tcp.seen[1].flags = IP_CT_TCP_FLAG_SACK_PERM |
- IP_CT_TCP_FLAG_BE_LIBERAL;
- }
- /* tcp_packet will set them */
- ct->proto.tcp.last_index = TCP_NONE_SET;
- pr_debug("tcp_new: sender end=%u maxend=%u maxwin=%u scale=%i "
- "receiver end=%u maxend=%u maxwin=%u scale=%i\n",
- sender->td_end, sender->td_maxend, sender->td_maxwin,
- sender->td_scale,
- receiver->td_end, receiver->td_maxend, receiver->td_maxwin,
- receiver->td_scale);
- return true;
- }
- #if IS_ENABLED(CONFIG_NF_CT_NETLINK)
- #include <linux/netfilter/nfnetlink.h>
- #include <linux/netfilter/nfnetlink_conntrack.h>
- static int tcp_to_nlattr(struct sk_buff *skb, struct nlattr *nla,
- struct nf_conn *ct)
- {
- struct nlattr *nest_parms;
- struct nf_ct_tcp_flags tmp = {};
- spin_lock_bh(&ct->lock);
- nest_parms = nla_nest_start(skb, CTA_PROTOINFO_TCP | NLA_F_NESTED);
- if (!nest_parms)
- goto nla_put_failure;
- if (nla_put_u8(skb, CTA_PROTOINFO_TCP_STATE, ct->proto.tcp.state) ||
- nla_put_u8(skb, CTA_PROTOINFO_TCP_WSCALE_ORIGINAL,
- ct->proto.tcp.seen[0].td_scale) ||
- nla_put_u8(skb, CTA_PROTOINFO_TCP_WSCALE_REPLY,
- ct->proto.tcp.seen[1].td_scale))
- goto nla_put_failure;
- tmp.flags = ct->proto.tcp.seen[0].flags;
- if (nla_put(skb, CTA_PROTOINFO_TCP_FLAGS_ORIGINAL,
- sizeof(struct nf_ct_tcp_flags), &tmp))
- goto nla_put_failure;
- tmp.flags = ct->proto.tcp.seen[1].flags;
- if (nla_put(skb, CTA_PROTOINFO_TCP_FLAGS_REPLY,
- sizeof(struct nf_ct_tcp_flags), &tmp))
- goto nla_put_failure;
- spin_unlock_bh(&ct->lock);
- nla_nest_end(skb, nest_parms);
- return 0;
- nla_put_failure:
- spin_unlock_bh(&ct->lock);
- return -1;
- }
- static const struct nla_policy tcp_nla_policy[CTA_PROTOINFO_TCP_MAX+1] = {
- [CTA_PROTOINFO_TCP_STATE] = { .type = NLA_U8 },
- [CTA_PROTOINFO_TCP_WSCALE_ORIGINAL] = { .type = NLA_U8 },
- [CTA_PROTOINFO_TCP_WSCALE_REPLY] = { .type = NLA_U8 },
- [CTA_PROTOINFO_TCP_FLAGS_ORIGINAL] = { .len = sizeof(struct nf_ct_tcp_flags) },
- [CTA_PROTOINFO_TCP_FLAGS_REPLY] = { .len = sizeof(struct nf_ct_tcp_flags) },
- };
- static int nlattr_to_tcp(struct nlattr *cda[], struct nf_conn *ct)
- {
- struct nlattr *pattr = cda[CTA_PROTOINFO_TCP];
- struct nlattr *tb[CTA_PROTOINFO_TCP_MAX+1];
- int err;
- /* updates could not contain anything about the private
- * protocol info, in that case skip the parsing */
- if (!pattr)
- return 0;
- err = nla_parse_nested(tb, CTA_PROTOINFO_TCP_MAX, pattr, tcp_nla_policy);
- if (err < 0)
- return err;
- if (tb[CTA_PROTOINFO_TCP_STATE] &&
- nla_get_u8(tb[CTA_PROTOINFO_TCP_STATE]) >= TCP_CONNTRACK_MAX)
- return -EINVAL;
- spin_lock_bh(&ct->lock);
- if (tb[CTA_PROTOINFO_TCP_STATE])
- ct->proto.tcp.state = nla_get_u8(tb[CTA_PROTOINFO_TCP_STATE]);
- if (tb[CTA_PROTOINFO_TCP_FLAGS_ORIGINAL]) {
- struct nf_ct_tcp_flags *attr =
- nla_data(tb[CTA_PROTOINFO_TCP_FLAGS_ORIGINAL]);
- ct->proto.tcp.seen[0].flags &= ~attr->mask;
- ct->proto.tcp.seen[0].flags |= attr->flags & attr->mask;
- }
- if (tb[CTA_PROTOINFO_TCP_FLAGS_REPLY]) {
- struct nf_ct_tcp_flags *attr =
- nla_data(tb[CTA_PROTOINFO_TCP_FLAGS_REPLY]);
- ct->proto.tcp.seen[1].flags &= ~attr->mask;
- ct->proto.tcp.seen[1].flags |= attr->flags & attr->mask;
- }
- if (tb[CTA_PROTOINFO_TCP_WSCALE_ORIGINAL] &&
- tb[CTA_PROTOINFO_TCP_WSCALE_REPLY] &&
- ct->proto.tcp.seen[0].flags & IP_CT_TCP_FLAG_WINDOW_SCALE &&
- ct->proto.tcp.seen[1].flags & IP_CT_TCP_FLAG_WINDOW_SCALE) {
- ct->proto.tcp.seen[0].td_scale =
- nla_get_u8(tb[CTA_PROTOINFO_TCP_WSCALE_ORIGINAL]);
- ct->proto.tcp.seen[1].td_scale =
- nla_get_u8(tb[CTA_PROTOINFO_TCP_WSCALE_REPLY]);
- }
- spin_unlock_bh(&ct->lock);
- return 0;
- }
- static int tcp_nlattr_size(void)
- {
- return nla_total_size(0) /* CTA_PROTOINFO_TCP */
- + nla_policy_len(tcp_nla_policy, CTA_PROTOINFO_TCP_MAX + 1);
- }
- static int tcp_nlattr_tuple_size(void)
- {
- return nla_policy_len(nf_ct_port_nla_policy, CTA_PROTO_MAX + 1);
- }
- #endif
- #if IS_ENABLED(CONFIG_NF_CT_NETLINK_TIMEOUT)
- #include <linux/netfilter/nfnetlink.h>
- #include <linux/netfilter/nfnetlink_cttimeout.h>
- static int tcp_timeout_nlattr_to_obj(struct nlattr *tb[],
- struct net *net, void *data)
- {
- unsigned int *timeouts = data;
- struct nf_tcp_net *tn = tcp_pernet(net);
- int i;
- /* set default TCP timeouts. */
- for (i=0; i<TCP_CONNTRACK_TIMEOUT_MAX; i++)
- timeouts[i] = tn->timeouts[i];
- if (tb[CTA_TIMEOUT_TCP_SYN_SENT]) {
- timeouts[TCP_CONNTRACK_SYN_SENT] =
- ntohl(nla_get_be32(tb[CTA_TIMEOUT_TCP_SYN_SENT]))*HZ;
- }
- if (tb[CTA_TIMEOUT_TCP_SYN_RECV]) {
- timeouts[TCP_CONNTRACK_SYN_RECV] =
- ntohl(nla_get_be32(tb[CTA_TIMEOUT_TCP_SYN_RECV]))*HZ;
- }
- if (tb[CTA_TIMEOUT_TCP_ESTABLISHED]) {
- timeouts[TCP_CONNTRACK_ESTABLISHED] =
- ntohl(nla_get_be32(tb[CTA_TIMEOUT_TCP_ESTABLISHED]))*HZ;
- }
- if (tb[CTA_TIMEOUT_TCP_FIN_WAIT]) {
- timeouts[TCP_CONNTRACK_FIN_WAIT] =
- ntohl(nla_get_be32(tb[CTA_TIMEOUT_TCP_FIN_WAIT]))*HZ;
- }
- if (tb[CTA_TIMEOUT_TCP_CLOSE_WAIT]) {
- timeouts[TCP_CONNTRACK_CLOSE_WAIT] =
- ntohl(nla_get_be32(tb[CTA_TIMEOUT_TCP_CLOSE_WAIT]))*HZ;
- }
- if (tb[CTA_TIMEOUT_TCP_LAST_ACK]) {
- timeouts[TCP_CONNTRACK_LAST_ACK] =
- ntohl(nla_get_be32(tb[CTA_TIMEOUT_TCP_LAST_ACK]))*HZ;
- }
- if (tb[CTA_TIMEOUT_TCP_TIME_WAIT]) {
- timeouts[TCP_CONNTRACK_TIME_WAIT] =
- ntohl(nla_get_be32(tb[CTA_TIMEOUT_TCP_TIME_WAIT]))*HZ;
- }
- if (tb[CTA_TIMEOUT_TCP_CLOSE]) {
- timeouts[TCP_CONNTRACK_CLOSE] =
- ntohl(nla_get_be32(tb[CTA_TIMEOUT_TCP_CLOSE]))*HZ;
- }
- if (tb[CTA_TIMEOUT_TCP_SYN_SENT2]) {
- timeouts[TCP_CONNTRACK_SYN_SENT2] =
- ntohl(nla_get_be32(tb[CTA_TIMEOUT_TCP_SYN_SENT2]))*HZ;
- }
- if (tb[CTA_TIMEOUT_TCP_RETRANS]) {
- timeouts[TCP_CONNTRACK_RETRANS] =
- ntohl(nla_get_be32(tb[CTA_TIMEOUT_TCP_RETRANS]))*HZ;
- }
- if (tb[CTA_TIMEOUT_TCP_UNACK]) {
- timeouts[TCP_CONNTRACK_UNACK] =
- ntohl(nla_get_be32(tb[CTA_TIMEOUT_TCP_UNACK]))*HZ;
- }
- return 0;
- }
- static int
- tcp_timeout_obj_to_nlattr(struct sk_buff *skb, const void *data)
- {
- const unsigned int *timeouts = data;
- if (nla_put_be32(skb, CTA_TIMEOUT_TCP_SYN_SENT,
- htonl(timeouts[TCP_CONNTRACK_SYN_SENT] / HZ)) ||
- nla_put_be32(skb, CTA_TIMEOUT_TCP_SYN_RECV,
- htonl(timeouts[TCP_CONNTRACK_SYN_RECV] / HZ)) ||
- nla_put_be32(skb, CTA_TIMEOUT_TCP_ESTABLISHED,
- htonl(timeouts[TCP_CONNTRACK_ESTABLISHED] / HZ)) ||
- nla_put_be32(skb, CTA_TIMEOUT_TCP_FIN_WAIT,
- htonl(timeouts[TCP_CONNTRACK_FIN_WAIT] / HZ)) ||
- nla_put_be32(skb, CTA_TIMEOUT_TCP_CLOSE_WAIT,
- htonl(timeouts[TCP_CONNTRACK_CLOSE_WAIT] / HZ)) ||
- nla_put_be32(skb, CTA_TIMEOUT_TCP_LAST_ACK,
- htonl(timeouts[TCP_CONNTRACK_LAST_ACK] / HZ)) ||
- nla_put_be32(skb, CTA_TIMEOUT_TCP_TIME_WAIT,
- htonl(timeouts[TCP_CONNTRACK_TIME_WAIT] / HZ)) ||
- nla_put_be32(skb, CTA_TIMEOUT_TCP_CLOSE,
- htonl(timeouts[TCP_CONNTRACK_CLOSE] / HZ)) ||
- nla_put_be32(skb, CTA_TIMEOUT_TCP_SYN_SENT2,
- htonl(timeouts[TCP_CONNTRACK_SYN_SENT2] / HZ)) ||
- nla_put_be32(skb, CTA_TIMEOUT_TCP_RETRANS,
- htonl(timeouts[TCP_CONNTRACK_RETRANS] / HZ)) ||
- nla_put_be32(skb, CTA_TIMEOUT_TCP_UNACK,
- htonl(timeouts[TCP_CONNTRACK_UNACK] / HZ)))
- goto nla_put_failure;
- return 0;
- nla_put_failure:
- return -ENOSPC;
- }
- static const struct nla_policy tcp_timeout_nla_policy[CTA_TIMEOUT_TCP_MAX+1] = {
- [CTA_TIMEOUT_TCP_SYN_SENT] = { .type = NLA_U32 },
- [CTA_TIMEOUT_TCP_SYN_RECV] = { .type = NLA_U32 },
- [CTA_TIMEOUT_TCP_ESTABLISHED] = { .type = NLA_U32 },
- [CTA_TIMEOUT_TCP_FIN_WAIT] = { .type = NLA_U32 },
- [CTA_TIMEOUT_TCP_CLOSE_WAIT] = { .type = NLA_U32 },
- [CTA_TIMEOUT_TCP_LAST_ACK] = { .type = NLA_U32 },
- [CTA_TIMEOUT_TCP_TIME_WAIT] = { .type = NLA_U32 },
- [CTA_TIMEOUT_TCP_CLOSE] = { .type = NLA_U32 },
- [CTA_TIMEOUT_TCP_SYN_SENT2] = { .type = NLA_U32 },
- [CTA_TIMEOUT_TCP_RETRANS] = { .type = NLA_U32 },
- [CTA_TIMEOUT_TCP_UNACK] = { .type = NLA_U32 },
- };
- #endif /* CONFIG_NF_CT_NETLINK_TIMEOUT */
- #ifdef CONFIG_SYSCTL
- static struct ctl_table tcp_sysctl_table[] = {
- {
- .procname = "nf_conntrack_tcp_timeout_syn_sent",
- .maxlen = sizeof(unsigned int),
- .mode = 0644,
- .proc_handler = proc_dointvec_jiffies,
- },
- {
- .procname = "nf_conntrack_tcp_timeout_syn_recv",
- .maxlen = sizeof(unsigned int),
- .mode = 0644,
- .proc_handler = proc_dointvec_jiffies,
- },
- {
- .procname = "nf_conntrack_tcp_timeout_established",
- .maxlen = sizeof(unsigned int),
- .mode = 0644,
- .proc_handler = proc_dointvec_jiffies,
- },
- {
- .procname = "nf_conntrack_tcp_timeout_fin_wait",
- .maxlen = sizeof(unsigned int),
- .mode = 0644,
- .proc_handler = proc_dointvec_jiffies,
- },
- {
- .procname = "nf_conntrack_tcp_timeout_close_wait",
- .maxlen = sizeof(unsigned int),
- .mode = 0644,
- .proc_handler = proc_dointvec_jiffies,
- },
- {
- .procname = "nf_conntrack_tcp_timeout_last_ack",
- .maxlen = sizeof(unsigned int),
- .mode = 0644,
- .proc_handler = proc_dointvec_jiffies,
- },
- {
- .procname = "nf_conntrack_tcp_timeout_time_wait",
- .maxlen = sizeof(unsigned int),
- .mode = 0644,
- .proc_handler = proc_dointvec_jiffies,
- },
- {
- .procname = "nf_conntrack_tcp_timeout_close",
- .maxlen = sizeof(unsigned int),
- .mode = 0644,
- .proc_handler = proc_dointvec_jiffies,
- },
- {
- .procname = "nf_conntrack_tcp_timeout_max_retrans",
- .maxlen = sizeof(unsigned int),
- .mode = 0644,
- .proc_handler = proc_dointvec_jiffies,
- },
- {
- .procname = "nf_conntrack_tcp_timeout_unacknowledged",
- .maxlen = sizeof(unsigned int),
- .mode = 0644,
- .proc_handler = proc_dointvec_jiffies,
- },
- {
- .procname = "nf_conntrack_tcp_loose",
- .maxlen = sizeof(unsigned int),
- .mode = 0644,
- .proc_handler = proc_dointvec,
- },
- {
- .procname = "nf_conntrack_tcp_be_liberal",
- .maxlen = sizeof(unsigned int),
- .mode = 0644,
- .proc_handler = proc_dointvec,
- },
- {
- .procname = "nf_conntrack_tcp_max_retrans",
- .maxlen = sizeof(unsigned int),
- .mode = 0644,
- .proc_handler = proc_dointvec,
- },
- { }
- };
- #ifdef CONFIG_NF_CONNTRACK_PROC_COMPAT
- static struct ctl_table tcp_compat_sysctl_table[] = {
- {
- .procname = "ip_conntrack_tcp_timeout_syn_sent",
- .maxlen = sizeof(unsigned int),
- .mode = 0644,
- .proc_handler = proc_dointvec_jiffies,
- },
- {
- .procname = "ip_conntrack_tcp_timeout_syn_sent2",
- .maxlen = sizeof(unsigned int),
- .mode = 0644,
- .proc_handler = proc_dointvec_jiffies,
- },
- {
- .procname = "ip_conntrack_tcp_timeout_syn_recv",
- .maxlen = sizeof(unsigned int),
- .mode = 0644,
- .proc_handler = proc_dointvec_jiffies,
- },
- {
- .procname = "ip_conntrack_tcp_timeout_established",
- .maxlen = sizeof(unsigned int),
- .mode = 0644,
- .proc_handler = proc_dointvec_jiffies,
- },
- {
- .procname = "ip_conntrack_tcp_timeout_fin_wait",
- .maxlen = sizeof(unsigned int),
- .mode = 0644,
- .proc_handler = proc_dointvec_jiffies,
- },
- {
- .procname = "ip_conntrack_tcp_timeout_close_wait",
- .maxlen = sizeof(unsigned int),
- .mode = 0644,
- .proc_handler = proc_dointvec_jiffies,
- },
- {
- .procname = "ip_conntrack_tcp_timeout_last_ack",
- .maxlen = sizeof(unsigned int),
- .mode = 0644,
- .proc_handler = proc_dointvec_jiffies,
- },
- {
- .procname = "ip_conntrack_tcp_timeout_time_wait",
- .maxlen = sizeof(unsigned int),
- .mode = 0644,
- .proc_handler = proc_dointvec_jiffies,
- },
- {
- .procname = "ip_conntrack_tcp_timeout_close",
- .maxlen = sizeof(unsigned int),
- .mode = 0644,
- .proc_handler = proc_dointvec_jiffies,
- },
- {
- .procname = "ip_conntrack_tcp_timeout_max_retrans",
- .maxlen = sizeof(unsigned int),
- .mode = 0644,
- .proc_handler = proc_dointvec_jiffies,
- },
- {
- .procname = "ip_conntrack_tcp_loose",
- .maxlen = sizeof(unsigned int),
- .mode = 0644,
- .proc_handler = proc_dointvec,
- },
- {
- .procname = "ip_conntrack_tcp_be_liberal",
- .maxlen = sizeof(unsigned int),
- .mode = 0644,
- .proc_handler = proc_dointvec,
- },
- {
- .procname = "ip_conntrack_tcp_max_retrans",
- .maxlen = sizeof(unsigned int),
- .mode = 0644,
- .proc_handler = proc_dointvec,
- },
- { }
- };
- #endif /* CONFIG_NF_CONNTRACK_PROC_COMPAT */
- #endif /* CONFIG_SYSCTL */
- static int tcp_kmemdup_sysctl_table(struct nf_proto_net *pn,
- struct nf_tcp_net *tn)
- {
- #ifdef CONFIG_SYSCTL
- if (pn->ctl_table)
- return 0;
- pn->ctl_table = kmemdup(tcp_sysctl_table,
- sizeof(tcp_sysctl_table),
- GFP_KERNEL);
- if (!pn->ctl_table)
- return -ENOMEM;
- pn->ctl_table[0].data = &tn->timeouts[TCP_CONNTRACK_SYN_SENT];
- pn->ctl_table[1].data = &tn->timeouts[TCP_CONNTRACK_SYN_RECV];
- pn->ctl_table[2].data = &tn->timeouts[TCP_CONNTRACK_ESTABLISHED];
- pn->ctl_table[3].data = &tn->timeouts[TCP_CONNTRACK_FIN_WAIT];
- pn->ctl_table[4].data = &tn->timeouts[TCP_CONNTRACK_CLOSE_WAIT];
- pn->ctl_table[5].data = &tn->timeouts[TCP_CONNTRACK_LAST_ACK];
- pn->ctl_table[6].data = &tn->timeouts[TCP_CONNTRACK_TIME_WAIT];
- pn->ctl_table[7].data = &tn->timeouts[TCP_CONNTRACK_CLOSE];
- pn->ctl_table[8].data = &tn->timeouts[TCP_CONNTRACK_RETRANS];
- pn->ctl_table[9].data = &tn->timeouts[TCP_CONNTRACK_UNACK];
- pn->ctl_table[10].data = &tn->tcp_loose;
- pn->ctl_table[11].data = &tn->tcp_be_liberal;
- pn->ctl_table[12].data = &tn->tcp_max_retrans;
- #endif
- return 0;
- }
- static int tcp_kmemdup_compat_sysctl_table(struct nf_proto_net *pn,
- struct nf_tcp_net *tn)
- {
- #ifdef CONFIG_SYSCTL
- #ifdef CONFIG_NF_CONNTRACK_PROC_COMPAT
- pn->ctl_compat_table = kmemdup(tcp_compat_sysctl_table,
- sizeof(tcp_compat_sysctl_table),
- GFP_KERNEL);
- if (!pn->ctl_compat_table)
- return -ENOMEM;
- pn->ctl_compat_table[0].data = &tn->timeouts[TCP_CONNTRACK_SYN_SENT];
- pn->ctl_compat_table[1].data = &tn->timeouts[TCP_CONNTRACK_SYN_SENT2];
- pn->ctl_compat_table[2].data = &tn->timeouts[TCP_CONNTRACK_SYN_RECV];
- pn->ctl_compat_table[3].data = &tn->timeouts[TCP_CONNTRACK_ESTABLISHED];
- pn->ctl_compat_table[4].data = &tn->timeouts[TCP_CONNTRACK_FIN_WAIT];
- pn->ctl_compat_table[5].data = &tn->timeouts[TCP_CONNTRACK_CLOSE_WAIT];
- pn->ctl_compat_table[6].data = &tn->timeouts[TCP_CONNTRACK_LAST_ACK];
- pn->ctl_compat_table[7].data = &tn->timeouts[TCP_CONNTRACK_TIME_WAIT];
- pn->ctl_compat_table[8].data = &tn->timeouts[TCP_CONNTRACK_CLOSE];
- pn->ctl_compat_table[9].data = &tn->timeouts[TCP_CONNTRACK_RETRANS];
- pn->ctl_compat_table[10].data = &tn->tcp_loose;
- pn->ctl_compat_table[11].data = &tn->tcp_be_liberal;
- pn->ctl_compat_table[12].data = &tn->tcp_max_retrans;
- #endif
- #endif
- return 0;
- }
- static int tcp_init_net(struct net *net, u_int16_t proto)
- {
- int ret;
- struct nf_tcp_net *tn = tcp_pernet(net);
- struct nf_proto_net *pn = &tn->pn;
- if (!pn->users) {
- int i;
- for (i = 0; i < TCP_CONNTRACK_TIMEOUT_MAX; i++)
- tn->timeouts[i] = tcp_timeouts[i];
- tn->tcp_loose = nf_ct_tcp_loose;
- tn->tcp_be_liberal = nf_ct_tcp_be_liberal;
- tn->tcp_max_retrans = nf_ct_tcp_max_retrans;
- }
- if (proto == AF_INET) {
- ret = tcp_kmemdup_compat_sysctl_table(pn, tn);
- if (ret < 0)
- return ret;
- ret = tcp_kmemdup_sysctl_table(pn, tn);
- if (ret < 0)
- nf_ct_kfree_compat_sysctl_table(pn);
- } else
- ret = tcp_kmemdup_sysctl_table(pn, tn);
- return ret;
- }
- static struct nf_proto_net *tcp_get_net_proto(struct net *net)
- {
- return &net->ct.nf_ct_proto.tcp.pn;
- }
- struct nf_conntrack_l4proto nf_conntrack_l4proto_tcp4 __read_mostly =
- {
- .l3proto = PF_INET,
- .l4proto = IPPROTO_TCP,
- .name = "tcp",
- .pkt_to_tuple = tcp_pkt_to_tuple,
- .invert_tuple = tcp_invert_tuple,
- .print_tuple = tcp_print_tuple,
- .print_conntrack = tcp_print_conntrack,
- .packet = tcp_packet,
- .get_timeouts = tcp_get_timeouts,
- .new = tcp_new,
- .error = tcp_error,
- #if IS_ENABLED(CONFIG_NF_CT_NETLINK)
- .to_nlattr = tcp_to_nlattr,
- .nlattr_size = tcp_nlattr_size,
- .from_nlattr = nlattr_to_tcp,
- .tuple_to_nlattr = nf_ct_port_tuple_to_nlattr,
- .nlattr_to_tuple = nf_ct_port_nlattr_to_tuple,
- .nlattr_tuple_size = tcp_nlattr_tuple_size,
- .nla_policy = nf_ct_port_nla_policy,
- #endif
- #if IS_ENABLED(CONFIG_NF_CT_NETLINK_TIMEOUT)
- .ctnl_timeout = {
- .nlattr_to_obj = tcp_timeout_nlattr_to_obj,
- .obj_to_nlattr = tcp_timeout_obj_to_nlattr,
- .nlattr_max = CTA_TIMEOUT_TCP_MAX,
- .obj_size = sizeof(unsigned int) *
- TCP_CONNTRACK_TIMEOUT_MAX,
- .nla_policy = tcp_timeout_nla_policy,
- },
- #endif /* CONFIG_NF_CT_NETLINK_TIMEOUT */
- .init_net = tcp_init_net,
- .get_net_proto = tcp_get_net_proto,
- };
- EXPORT_SYMBOL_GPL(nf_conntrack_l4proto_tcp4);
- struct nf_conntrack_l4proto nf_conntrack_l4proto_tcp6 __read_mostly =
- {
- .l3proto = PF_INET6,
- .l4proto = IPPROTO_TCP,
- .name = "tcp",
- .pkt_to_tuple = tcp_pkt_to_tuple,
- .invert_tuple = tcp_invert_tuple,
- .print_tuple = tcp_print_tuple,
- .print_conntrack = tcp_print_conntrack,
- .packet = tcp_packet,
- .get_timeouts = tcp_get_timeouts,
- .new = tcp_new,
- .error = tcp_error,
- #if IS_ENABLED(CONFIG_NF_CT_NETLINK)
- .to_nlattr = tcp_to_nlattr,
- .nlattr_size = tcp_nlattr_size,
- .from_nlattr = nlattr_to_tcp,
- .tuple_to_nlattr = nf_ct_port_tuple_to_nlattr,
- .nlattr_to_tuple = nf_ct_port_nlattr_to_tuple,
- .nlattr_tuple_size = tcp_nlattr_tuple_size,
- .nla_policy = nf_ct_port_nla_policy,
- #endif
- #if IS_ENABLED(CONFIG_NF_CT_NETLINK_TIMEOUT)
- .ctnl_timeout = {
- .nlattr_to_obj = tcp_timeout_nlattr_to_obj,
- .obj_to_nlattr = tcp_timeout_obj_to_nlattr,
- .nlattr_max = CTA_TIMEOUT_TCP_MAX,
- .obj_size = sizeof(unsigned int) *
- TCP_CONNTRACK_TIMEOUT_MAX,
- .nla_policy = tcp_timeout_nla_policy,
- },
- #endif /* CONFIG_NF_CT_NETLINK_TIMEOUT */
- .init_net = tcp_init_net,
- .get_net_proto = tcp_get_net_proto,
- };
- EXPORT_SYMBOL_GPL(nf_conntrack_l4proto_tcp6);
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