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- // SPDX-License-Identifier: GPL-2.0-only
- /*
- * Connection tracking protocol helper module for SCTP.
- *
- * Copyright (c) 2004 Kiran Kumar Immidi <immidi_kiran@yahoo.com>
- * Copyright (c) 2004-2012 Patrick McHardy <kaber@trash.net>
- *
- * SCTP is defined in RFC 2960. References to various sections in this code
- * are to this RFC.
- */
- #include <linux/types.h>
- #include <linux/timer.h>
- #include <linux/netfilter.h>
- #include <linux/in.h>
- #include <linux/ip.h>
- #include <linux/sctp.h>
- #include <linux/string.h>
- #include <linux/seq_file.h>
- #include <linux/spinlock.h>
- #include <linux/interrupt.h>
- #include <net/sctp/checksum.h>
- #include <net/netfilter/nf_log.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_timeout.h>
- /* FIXME: Examine ipfilter's timeouts and conntrack transitions more
- closely. They're more complex. --RR
- And so for me for SCTP :D -Kiran */
- static const char *const sctp_conntrack_names[] = {
- "NONE",
- "CLOSED",
- "COOKIE_WAIT",
- "COOKIE_ECHOED",
- "ESTABLISHED",
- "SHUTDOWN_SENT",
- "SHUTDOWN_RECD",
- "SHUTDOWN_ACK_SENT",
- "HEARTBEAT_SENT",
- "HEARTBEAT_ACKED",
- };
- #define SECS * HZ
- #define MINS * 60 SECS
- #define HOURS * 60 MINS
- #define DAYS * 24 HOURS
- static const unsigned int sctp_timeouts[SCTP_CONNTRACK_MAX] = {
- [SCTP_CONNTRACK_CLOSED] = 10 SECS,
- [SCTP_CONNTRACK_COOKIE_WAIT] = 3 SECS,
- [SCTP_CONNTRACK_COOKIE_ECHOED] = 3 SECS,
- [SCTP_CONNTRACK_ESTABLISHED] = 5 DAYS,
- [SCTP_CONNTRACK_SHUTDOWN_SENT] = 300 SECS / 1000,
- [SCTP_CONNTRACK_SHUTDOWN_RECD] = 300 SECS / 1000,
- [SCTP_CONNTRACK_SHUTDOWN_ACK_SENT] = 3 SECS,
- [SCTP_CONNTRACK_HEARTBEAT_SENT] = 30 SECS,
- [SCTP_CONNTRACK_HEARTBEAT_ACKED] = 210 SECS,
- };
- #define SCTP_FLAG_HEARTBEAT_VTAG_FAILED 1
- #define sNO SCTP_CONNTRACK_NONE
- #define sCL SCTP_CONNTRACK_CLOSED
- #define sCW SCTP_CONNTRACK_COOKIE_WAIT
- #define sCE SCTP_CONNTRACK_COOKIE_ECHOED
- #define sES SCTP_CONNTRACK_ESTABLISHED
- #define sSS SCTP_CONNTRACK_SHUTDOWN_SENT
- #define sSR SCTP_CONNTRACK_SHUTDOWN_RECD
- #define sSA SCTP_CONNTRACK_SHUTDOWN_ACK_SENT
- #define sHS SCTP_CONNTRACK_HEARTBEAT_SENT
- #define sHA SCTP_CONNTRACK_HEARTBEAT_ACKED
- #define sIV SCTP_CONNTRACK_MAX
- /*
- These are the descriptions of the states:
- NOTE: These state names are tantalizingly similar to the states of an
- SCTP endpoint. But the interpretation of the states is a little different,
- considering that these are the states of the connection and not of an end
- point. Please note the subtleties. -Kiran
- NONE - Nothing so far.
- COOKIE WAIT - We have seen an INIT chunk in the original direction, or also
- an INIT_ACK chunk in the reply direction.
- COOKIE ECHOED - We have seen a COOKIE_ECHO chunk in the original direction.
- ESTABLISHED - We have seen a COOKIE_ACK in the reply direction.
- SHUTDOWN_SENT - We have seen a SHUTDOWN chunk in the original direction.
- SHUTDOWN_RECD - We have seen a SHUTDOWN chunk in the reply directoin.
- SHUTDOWN_ACK_SENT - We have seen a SHUTDOWN_ACK chunk in the direction opposite
- to that of the SHUTDOWN chunk.
- CLOSED - We have seen a SHUTDOWN_COMPLETE chunk in the direction of
- the SHUTDOWN chunk. Connection is closed.
- HEARTBEAT_SENT - We have seen a HEARTBEAT in a new flow.
- HEARTBEAT_ACKED - We have seen a HEARTBEAT-ACK in the direction opposite to
- that of the HEARTBEAT chunk. Secondary connection is
- established.
- */
- /* TODO
- - I have assumed that the first INIT is in the original direction.
- This messes things when an INIT comes in the reply direction in CLOSED
- state.
- - Check the error type in the reply dir before transitioning from
- cookie echoed to closed.
- - Sec 5.2.4 of RFC 2960
- - Full Multi Homing support.
- */
- /* SCTP conntrack state transitions */
- static const u8 sctp_conntracks[2][11][SCTP_CONNTRACK_MAX] = {
- {
- /* ORIGINAL */
- /* sNO, sCL, sCW, sCE, sES, sSS, sSR, sSA, sHS, sHA */
- /* init */ {sCL, sCL, sCW, sCE, sES, sSS, sSR, sSA, sCW, sHA},
- /* init_ack */ {sCL, sCL, sCW, sCE, sES, sSS, sSR, sSA, sCL, sHA},
- /* abort */ {sCL, sCL, sCL, sCL, sCL, sCL, sCL, sCL, sCL, sCL},
- /* shutdown */ {sCL, sCL, sCW, sCE, sSS, sSS, sSR, sSA, sCL, sSS},
- /* shutdown_ack */ {sSA, sCL, sCW, sCE, sES, sSA, sSA, sSA, sSA, sHA},
- /* error */ {sCL, sCL, sCW, sCE, sES, sSS, sSR, sSA, sCL, sHA},/* Can't have Stale cookie*/
- /* cookie_echo */ {sCL, sCL, sCE, sCE, sES, sSS, sSR, sSA, sCL, sHA},/* 5.2.4 - Big TODO */
- /* cookie_ack */ {sCL, sCL, sCW, sCE, sES, sSS, sSR, sSA, sCL, sHA},/* Can't come in orig dir */
- /* shutdown_comp*/ {sCL, sCL, sCW, sCE, sES, sSS, sSR, sCL, sCL, sHA},
- /* heartbeat */ {sHS, sCL, sCW, sCE, sES, sSS, sSR, sSA, sHS, sHA},
- /* heartbeat_ack*/ {sCL, sCL, sCW, sCE, sES, sSS, sSR, sSA, sHS, sHA}
- },
- {
- /* REPLY */
- /* sNO, sCL, sCW, sCE, sES, sSS, sSR, sSA, sHS, sHA */
- /* init */ {sIV, sCL, sCW, sCE, sES, sSS, sSR, sSA, sIV, sHA},/* INIT in sCL Big TODO */
- /* init_ack */ {sIV, sCW, sCW, sCE, sES, sSS, sSR, sSA, sIV, sHA},
- /* abort */ {sIV, sCL, sCL, sCL, sCL, sCL, sCL, sCL, sIV, sCL},
- /* shutdown */ {sIV, sCL, sCW, sCE, sSR, sSS, sSR, sSA, sIV, sSR},
- /* shutdown_ack */ {sIV, sCL, sCW, sCE, sES, sSA, sSA, sSA, sIV, sHA},
- /* error */ {sIV, sCL, sCW, sCL, sES, sSS, sSR, sSA, sIV, sHA},
- /* cookie_echo */ {sIV, sCL, sCW, sCE, sES, sSS, sSR, sSA, sIV, sHA},/* Can't come in reply dir */
- /* cookie_ack */ {sIV, sCL, sCW, sES, sES, sSS, sSR, sSA, sIV, sHA},
- /* shutdown_comp*/ {sIV, sCL, sCW, sCE, sES, sSS, sSR, sCL, sIV, sHA},
- /* heartbeat */ {sIV, sCL, sCW, sCE, sES, sSS, sSR, sSA, sHS, sHA},
- /* heartbeat_ack*/ {sIV, sCL, sCW, sCE, sES, sSS, sSR, sSA, sHA, sHA}
- }
- };
- #ifdef CONFIG_NF_CONNTRACK_PROCFS
- /* Print out the private part of the conntrack. */
- static void sctp_print_conntrack(struct seq_file *s, struct nf_conn *ct)
- {
- seq_printf(s, "%s ", sctp_conntrack_names[ct->proto.sctp.state]);
- }
- #endif
- #define for_each_sctp_chunk(skb, sch, _sch, offset, dataoff, count) \
- for ((offset) = (dataoff) + sizeof(struct sctphdr), (count) = 0; \
- (offset) < (skb)->len && \
- ((sch) = skb_header_pointer((skb), (offset), sizeof(_sch), &(_sch))); \
- (offset) += (ntohs((sch)->length) + 3) & ~3, (count)++)
- /* Some validity checks to make sure the chunks are fine */
- static int do_basic_checks(struct nf_conn *ct,
- const struct sk_buff *skb,
- unsigned int dataoff,
- unsigned long *map)
- {
- u_int32_t offset, count;
- struct sctp_chunkhdr _sch, *sch;
- int flag;
- flag = 0;
- for_each_sctp_chunk (skb, sch, _sch, offset, dataoff, count) {
- pr_debug("Chunk Num: %d Type: %d\n", count, sch->type);
- if (sch->type == SCTP_CID_INIT ||
- sch->type == SCTP_CID_INIT_ACK ||
- sch->type == SCTP_CID_SHUTDOWN_COMPLETE)
- flag = 1;
- /*
- * Cookie Ack/Echo chunks not the first OR
- * Init / Init Ack / Shutdown compl chunks not the only chunks
- * OR zero-length.
- */
- if (((sch->type == SCTP_CID_COOKIE_ACK ||
- sch->type == SCTP_CID_COOKIE_ECHO ||
- flag) &&
- count != 0) || !sch->length) {
- pr_debug("Basic checks failed\n");
- return 1;
- }
- if (map)
- set_bit(sch->type, map);
- }
- pr_debug("Basic checks passed\n");
- return count == 0;
- }
- static int sctp_new_state(enum ip_conntrack_dir dir,
- enum sctp_conntrack cur_state,
- int chunk_type)
- {
- int i;
- pr_debug("Chunk type: %d\n", chunk_type);
- switch (chunk_type) {
- case SCTP_CID_INIT:
- pr_debug("SCTP_CID_INIT\n");
- i = 0;
- break;
- case SCTP_CID_INIT_ACK:
- pr_debug("SCTP_CID_INIT_ACK\n");
- i = 1;
- break;
- case SCTP_CID_ABORT:
- pr_debug("SCTP_CID_ABORT\n");
- i = 2;
- break;
- case SCTP_CID_SHUTDOWN:
- pr_debug("SCTP_CID_SHUTDOWN\n");
- i = 3;
- break;
- case SCTP_CID_SHUTDOWN_ACK:
- pr_debug("SCTP_CID_SHUTDOWN_ACK\n");
- i = 4;
- break;
- case SCTP_CID_ERROR:
- pr_debug("SCTP_CID_ERROR\n");
- i = 5;
- break;
- case SCTP_CID_COOKIE_ECHO:
- pr_debug("SCTP_CID_COOKIE_ECHO\n");
- i = 6;
- break;
- case SCTP_CID_COOKIE_ACK:
- pr_debug("SCTP_CID_COOKIE_ACK\n");
- i = 7;
- break;
- case SCTP_CID_SHUTDOWN_COMPLETE:
- pr_debug("SCTP_CID_SHUTDOWN_COMPLETE\n");
- i = 8;
- break;
- case SCTP_CID_HEARTBEAT:
- pr_debug("SCTP_CID_HEARTBEAT");
- i = 9;
- break;
- case SCTP_CID_HEARTBEAT_ACK:
- pr_debug("SCTP_CID_HEARTBEAT_ACK");
- i = 10;
- break;
- default:
- /* Other chunks like DATA or SACK do not change the state */
- pr_debug("Unknown chunk type, Will stay in %s\n",
- sctp_conntrack_names[cur_state]);
- return cur_state;
- }
- pr_debug("dir: %d cur_state: %s chunk_type: %d new_state: %s\n",
- dir, sctp_conntrack_names[cur_state], chunk_type,
- sctp_conntrack_names[sctp_conntracks[dir][i][cur_state]]);
- return sctp_conntracks[dir][i][cur_state];
- }
- /* Don't need lock here: this conntrack not in circulation yet */
- static noinline bool
- sctp_new(struct nf_conn *ct, const struct sk_buff *skb,
- const struct sctphdr *sh, unsigned int dataoff)
- {
- enum sctp_conntrack new_state;
- const struct sctp_chunkhdr *sch;
- struct sctp_chunkhdr _sch;
- u32 offset, count;
- memset(&ct->proto.sctp, 0, sizeof(ct->proto.sctp));
- new_state = SCTP_CONNTRACK_MAX;
- for_each_sctp_chunk(skb, sch, _sch, offset, dataoff, count) {
- new_state = sctp_new_state(IP_CT_DIR_ORIGINAL,
- SCTP_CONNTRACK_NONE, sch->type);
- /* Invalid: delete conntrack */
- if (new_state == SCTP_CONNTRACK_NONE ||
- new_state == SCTP_CONNTRACK_MAX) {
- pr_debug("nf_conntrack_sctp: invalid new deleting.\n");
- return false;
- }
- /* Copy the vtag into the state info */
- if (sch->type == SCTP_CID_INIT) {
- struct sctp_inithdr _inithdr, *ih;
- /* Sec 8.5.1 (A) */
- if (sh->vtag)
- return false;
- ih = skb_header_pointer(skb, offset + sizeof(_sch),
- sizeof(_inithdr), &_inithdr);
- if (!ih)
- return false;
- pr_debug("Setting vtag %x for new conn\n",
- ih->init_tag);
- ct->proto.sctp.vtag[IP_CT_DIR_REPLY] = ih->init_tag;
- } else if (sch->type == SCTP_CID_HEARTBEAT) {
- pr_debug("Setting vtag %x for secondary conntrack\n",
- sh->vtag);
- ct->proto.sctp.vtag[IP_CT_DIR_ORIGINAL] = sh->vtag;
- } else {
- /* If it is a shutdown ack OOTB packet, we expect a return
- shutdown complete, otherwise an ABORT Sec 8.4 (5) and (8) */
- pr_debug("Setting vtag %x for new conn OOTB\n",
- sh->vtag);
- ct->proto.sctp.vtag[IP_CT_DIR_REPLY] = sh->vtag;
- }
- ct->proto.sctp.state = SCTP_CONNTRACK_NONE;
- }
- return true;
- }
- static bool sctp_error(struct sk_buff *skb,
- unsigned int dataoff,
- const struct nf_hook_state *state)
- {
- const struct sctphdr *sh;
- const char *logmsg;
- if (skb->len < dataoff + sizeof(struct sctphdr)) {
- logmsg = "nf_ct_sctp: short packet ";
- goto out_invalid;
- }
- if (state->hook == NF_INET_PRE_ROUTING &&
- state->net->ct.sysctl_checksum &&
- skb->ip_summed == CHECKSUM_NONE) {
- if (skb_ensure_writable(skb, dataoff + sizeof(*sh))) {
- logmsg = "nf_ct_sctp: failed to read header ";
- goto out_invalid;
- }
- sh = (const struct sctphdr *)(skb->data + dataoff);
- if (sh->checksum != sctp_compute_cksum(skb, dataoff)) {
- logmsg = "nf_ct_sctp: bad CRC ";
- goto out_invalid;
- }
- skb->ip_summed = CHECKSUM_UNNECESSARY;
- }
- return false;
- out_invalid:
- nf_l4proto_log_invalid(skb, state->net, state->pf, IPPROTO_SCTP, "%s", logmsg);
- return true;
- }
- /* Returns verdict for packet, or -NF_ACCEPT for invalid. */
- int nf_conntrack_sctp_packet(struct nf_conn *ct,
- struct sk_buff *skb,
- unsigned int dataoff,
- enum ip_conntrack_info ctinfo,
- const struct nf_hook_state *state)
- {
- enum sctp_conntrack new_state, old_state;
- enum ip_conntrack_dir dir = CTINFO2DIR(ctinfo);
- const struct sctphdr *sh;
- struct sctphdr _sctph;
- const struct sctp_chunkhdr *sch;
- struct sctp_chunkhdr _sch;
- u_int32_t offset, count;
- unsigned int *timeouts;
- unsigned long map[256 / sizeof(unsigned long)] = { 0 };
- bool ignore = false;
- if (sctp_error(skb, dataoff, state))
- return -NF_ACCEPT;
- sh = skb_header_pointer(skb, dataoff, sizeof(_sctph), &_sctph);
- if (sh == NULL)
- goto out;
- if (do_basic_checks(ct, skb, dataoff, map) != 0)
- goto out;
- if (!nf_ct_is_confirmed(ct)) {
- /* If an OOTB packet has any of these chunks discard (Sec 8.4) */
- if (test_bit(SCTP_CID_ABORT, map) ||
- test_bit(SCTP_CID_SHUTDOWN_COMPLETE, map) ||
- test_bit(SCTP_CID_COOKIE_ACK, map))
- return -NF_ACCEPT;
- if (!sctp_new(ct, skb, sh, dataoff))
- return -NF_ACCEPT;
- }
- /* Check the verification tag (Sec 8.5) */
- if (!test_bit(SCTP_CID_INIT, map) &&
- !test_bit(SCTP_CID_SHUTDOWN_COMPLETE, map) &&
- !test_bit(SCTP_CID_COOKIE_ECHO, map) &&
- !test_bit(SCTP_CID_ABORT, map) &&
- !test_bit(SCTP_CID_SHUTDOWN_ACK, map) &&
- !test_bit(SCTP_CID_HEARTBEAT, map) &&
- !test_bit(SCTP_CID_HEARTBEAT_ACK, map) &&
- sh->vtag != ct->proto.sctp.vtag[dir]) {
- pr_debug("Verification tag check failed\n");
- goto out;
- }
- old_state = new_state = SCTP_CONNTRACK_NONE;
- spin_lock_bh(&ct->lock);
- for_each_sctp_chunk (skb, sch, _sch, offset, dataoff, count) {
- /* Special cases of Verification tag check (Sec 8.5.1) */
- if (sch->type == SCTP_CID_INIT) {
- /* Sec 8.5.1 (A) */
- if (sh->vtag != 0)
- goto out_unlock;
- } else if (sch->type == SCTP_CID_ABORT) {
- /* Sec 8.5.1 (B) */
- if (sh->vtag != ct->proto.sctp.vtag[dir] &&
- sh->vtag != ct->proto.sctp.vtag[!dir])
- goto out_unlock;
- } else if (sch->type == SCTP_CID_SHUTDOWN_COMPLETE) {
- /* Sec 8.5.1 (C) */
- if (sh->vtag != ct->proto.sctp.vtag[dir] &&
- sh->vtag != ct->proto.sctp.vtag[!dir] &&
- sch->flags & SCTP_CHUNK_FLAG_T)
- goto out_unlock;
- } else if (sch->type == SCTP_CID_COOKIE_ECHO) {
- /* Sec 8.5.1 (D) */
- if (sh->vtag != ct->proto.sctp.vtag[dir])
- goto out_unlock;
- } else if (sch->type == SCTP_CID_HEARTBEAT) {
- if (ct->proto.sctp.vtag[dir] == 0) {
- pr_debug("Setting %d vtag %x for dir %d\n", sch->type, sh->vtag, dir);
- ct->proto.sctp.vtag[dir] = sh->vtag;
- } else if (sh->vtag != ct->proto.sctp.vtag[dir]) {
- if (test_bit(SCTP_CID_DATA, map) || ignore)
- goto out_unlock;
- ct->proto.sctp.flags |= SCTP_FLAG_HEARTBEAT_VTAG_FAILED;
- ct->proto.sctp.last_dir = dir;
- ignore = true;
- continue;
- } else if (ct->proto.sctp.flags & SCTP_FLAG_HEARTBEAT_VTAG_FAILED) {
- ct->proto.sctp.flags &= ~SCTP_FLAG_HEARTBEAT_VTAG_FAILED;
- }
- } else if (sch->type == SCTP_CID_HEARTBEAT_ACK) {
- if (ct->proto.sctp.vtag[dir] == 0) {
- pr_debug("Setting vtag %x for dir %d\n",
- sh->vtag, dir);
- ct->proto.sctp.vtag[dir] = sh->vtag;
- } else if (sh->vtag != ct->proto.sctp.vtag[dir]) {
- if (test_bit(SCTP_CID_DATA, map) || ignore)
- goto out_unlock;
- if ((ct->proto.sctp.flags & SCTP_FLAG_HEARTBEAT_VTAG_FAILED) == 0 ||
- ct->proto.sctp.last_dir == dir)
- goto out_unlock;
- ct->proto.sctp.flags &= ~SCTP_FLAG_HEARTBEAT_VTAG_FAILED;
- ct->proto.sctp.vtag[dir] = sh->vtag;
- ct->proto.sctp.vtag[!dir] = 0;
- } else if (ct->proto.sctp.flags & SCTP_FLAG_HEARTBEAT_VTAG_FAILED) {
- ct->proto.sctp.flags &= ~SCTP_FLAG_HEARTBEAT_VTAG_FAILED;
- }
- }
- old_state = ct->proto.sctp.state;
- new_state = sctp_new_state(dir, old_state, sch->type);
- /* Invalid */
- if (new_state == SCTP_CONNTRACK_MAX) {
- pr_debug("nf_conntrack_sctp: Invalid dir=%i ctype=%u "
- "conntrack=%u\n",
- dir, sch->type, old_state);
- goto out_unlock;
- }
- /* If it is an INIT or an INIT ACK note down the vtag */
- if (sch->type == SCTP_CID_INIT ||
- sch->type == SCTP_CID_INIT_ACK) {
- struct sctp_inithdr _inithdr, *ih;
- ih = skb_header_pointer(skb, offset + sizeof(_sch),
- sizeof(_inithdr), &_inithdr);
- if (ih == NULL)
- goto out_unlock;
- pr_debug("Setting vtag %x for dir %d\n",
- ih->init_tag, !dir);
- ct->proto.sctp.vtag[!dir] = ih->init_tag;
- /* don't renew timeout on init retransmit so
- * port reuse by client or NAT middlebox cannot
- * keep entry alive indefinitely (incl. nat info).
- */
- if (new_state == SCTP_CONNTRACK_CLOSED &&
- old_state == SCTP_CONNTRACK_CLOSED &&
- nf_ct_is_confirmed(ct))
- ignore = true;
- }
- ct->proto.sctp.state = new_state;
- if (old_state != new_state)
- nf_conntrack_event_cache(IPCT_PROTOINFO, ct);
- }
- spin_unlock_bh(&ct->lock);
- /* allow but do not refresh timeout */
- if (ignore)
- return NF_ACCEPT;
- timeouts = nf_ct_timeout_lookup(ct);
- if (!timeouts)
- timeouts = nf_sctp_pernet(nf_ct_net(ct))->timeouts;
- nf_ct_refresh_acct(ct, ctinfo, skb, timeouts[new_state]);
- if (old_state == SCTP_CONNTRACK_COOKIE_ECHOED &&
- dir == IP_CT_DIR_REPLY &&
- new_state == SCTP_CONNTRACK_ESTABLISHED) {
- pr_debug("Setting assured bit\n");
- set_bit(IPS_ASSURED_BIT, &ct->status);
- nf_conntrack_event_cache(IPCT_ASSURED, ct);
- }
- return NF_ACCEPT;
- out_unlock:
- spin_unlock_bh(&ct->lock);
- out:
- return -NF_ACCEPT;
- }
- static bool sctp_can_early_drop(const struct nf_conn *ct)
- {
- switch (ct->proto.sctp.state) {
- case SCTP_CONNTRACK_SHUTDOWN_SENT:
- case SCTP_CONNTRACK_SHUTDOWN_RECD:
- case SCTP_CONNTRACK_SHUTDOWN_ACK_SENT:
- return true;
- default:
- break;
- }
- return false;
- }
- #if IS_ENABLED(CONFIG_NF_CT_NETLINK)
- #include <linux/netfilter/nfnetlink.h>
- #include <linux/netfilter/nfnetlink_conntrack.h>
- static int sctp_to_nlattr(struct sk_buff *skb, struct nlattr *nla,
- struct nf_conn *ct)
- {
- struct nlattr *nest_parms;
- spin_lock_bh(&ct->lock);
- nest_parms = nla_nest_start(skb, CTA_PROTOINFO_SCTP);
- if (!nest_parms)
- goto nla_put_failure;
- if (nla_put_u8(skb, CTA_PROTOINFO_SCTP_STATE, ct->proto.sctp.state) ||
- nla_put_be32(skb, CTA_PROTOINFO_SCTP_VTAG_ORIGINAL,
- ct->proto.sctp.vtag[IP_CT_DIR_ORIGINAL]) ||
- nla_put_be32(skb, CTA_PROTOINFO_SCTP_VTAG_REPLY,
- ct->proto.sctp.vtag[IP_CT_DIR_REPLY]))
- 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 sctp_nla_policy[CTA_PROTOINFO_SCTP_MAX+1] = {
- [CTA_PROTOINFO_SCTP_STATE] = { .type = NLA_U8 },
- [CTA_PROTOINFO_SCTP_VTAG_ORIGINAL] = { .type = NLA_U32 },
- [CTA_PROTOINFO_SCTP_VTAG_REPLY] = { .type = NLA_U32 },
- };
- #define SCTP_NLATTR_SIZE ( \
- NLA_ALIGN(NLA_HDRLEN + 1) + \
- NLA_ALIGN(NLA_HDRLEN + 4) + \
- NLA_ALIGN(NLA_HDRLEN + 4))
- static int nlattr_to_sctp(struct nlattr *cda[], struct nf_conn *ct)
- {
- struct nlattr *attr = cda[CTA_PROTOINFO_SCTP];
- struct nlattr *tb[CTA_PROTOINFO_SCTP_MAX+1];
- int err;
- /* updates may not contain the internal protocol info, skip parsing */
- if (!attr)
- return 0;
- err = nla_parse_nested_deprecated(tb, CTA_PROTOINFO_SCTP_MAX, attr,
- sctp_nla_policy, NULL);
- if (err < 0)
- return err;
- if (!tb[CTA_PROTOINFO_SCTP_STATE] ||
- !tb[CTA_PROTOINFO_SCTP_VTAG_ORIGINAL] ||
- !tb[CTA_PROTOINFO_SCTP_VTAG_REPLY])
- return -EINVAL;
- spin_lock_bh(&ct->lock);
- ct->proto.sctp.state = nla_get_u8(tb[CTA_PROTOINFO_SCTP_STATE]);
- ct->proto.sctp.vtag[IP_CT_DIR_ORIGINAL] =
- nla_get_be32(tb[CTA_PROTOINFO_SCTP_VTAG_ORIGINAL]);
- ct->proto.sctp.vtag[IP_CT_DIR_REPLY] =
- nla_get_be32(tb[CTA_PROTOINFO_SCTP_VTAG_REPLY]);
- spin_unlock_bh(&ct->lock);
- return 0;
- }
- #endif
- #ifdef CONFIG_NF_CONNTRACK_TIMEOUT
- #include <linux/netfilter/nfnetlink.h>
- #include <linux/netfilter/nfnetlink_cttimeout.h>
- static int sctp_timeout_nlattr_to_obj(struct nlattr *tb[],
- struct net *net, void *data)
- {
- unsigned int *timeouts = data;
- struct nf_sctp_net *sn = nf_sctp_pernet(net);
- int i;
- if (!timeouts)
- timeouts = sn->timeouts;
- /* set default SCTP timeouts. */
- for (i=0; i<SCTP_CONNTRACK_MAX; i++)
- timeouts[i] = sn->timeouts[i];
- /* there's a 1:1 mapping between attributes and protocol states. */
- for (i=CTA_TIMEOUT_SCTP_UNSPEC+1; i<CTA_TIMEOUT_SCTP_MAX+1; i++) {
- if (tb[i]) {
- timeouts[i] = ntohl(nla_get_be32(tb[i])) * HZ;
- }
- }
- timeouts[CTA_TIMEOUT_SCTP_UNSPEC] = timeouts[CTA_TIMEOUT_SCTP_CLOSED];
- return 0;
- }
- static int
- sctp_timeout_obj_to_nlattr(struct sk_buff *skb, const void *data)
- {
- const unsigned int *timeouts = data;
- int i;
- for (i=CTA_TIMEOUT_SCTP_UNSPEC+1; i<CTA_TIMEOUT_SCTP_MAX+1; i++) {
- if (nla_put_be32(skb, i, htonl(timeouts[i] / HZ)))
- goto nla_put_failure;
- }
- return 0;
- nla_put_failure:
- return -ENOSPC;
- }
- static const struct nla_policy
- sctp_timeout_nla_policy[CTA_TIMEOUT_SCTP_MAX+1] = {
- [CTA_TIMEOUT_SCTP_CLOSED] = { .type = NLA_U32 },
- [CTA_TIMEOUT_SCTP_COOKIE_WAIT] = { .type = NLA_U32 },
- [CTA_TIMEOUT_SCTP_COOKIE_ECHOED] = { .type = NLA_U32 },
- [CTA_TIMEOUT_SCTP_ESTABLISHED] = { .type = NLA_U32 },
- [CTA_TIMEOUT_SCTP_SHUTDOWN_SENT] = { .type = NLA_U32 },
- [CTA_TIMEOUT_SCTP_SHUTDOWN_RECD] = { .type = NLA_U32 },
- [CTA_TIMEOUT_SCTP_SHUTDOWN_ACK_SENT] = { .type = NLA_U32 },
- [CTA_TIMEOUT_SCTP_HEARTBEAT_SENT] = { .type = NLA_U32 },
- [CTA_TIMEOUT_SCTP_HEARTBEAT_ACKED] = { .type = NLA_U32 },
- };
- #endif /* CONFIG_NF_CONNTRACK_TIMEOUT */
- void nf_conntrack_sctp_init_net(struct net *net)
- {
- struct nf_sctp_net *sn = nf_sctp_pernet(net);
- int i;
- for (i = 0; i < SCTP_CONNTRACK_MAX; i++)
- sn->timeouts[i] = sctp_timeouts[i];
- /* timeouts[0] is unused, init it so ->timeouts[0] contains
- * 'new' timeout, like udp or icmp.
- */
- sn->timeouts[0] = sctp_timeouts[SCTP_CONNTRACK_CLOSED];
- }
- const struct nf_conntrack_l4proto nf_conntrack_l4proto_sctp = {
- .l4proto = IPPROTO_SCTP,
- #ifdef CONFIG_NF_CONNTRACK_PROCFS
- .print_conntrack = sctp_print_conntrack,
- #endif
- .can_early_drop = sctp_can_early_drop,
- #if IS_ENABLED(CONFIG_NF_CT_NETLINK)
- .nlattr_size = SCTP_NLATTR_SIZE,
- .to_nlattr = sctp_to_nlattr,
- .from_nlattr = nlattr_to_sctp,
- .tuple_to_nlattr = nf_ct_port_tuple_to_nlattr,
- .nlattr_tuple_size = nf_ct_port_nlattr_tuple_size,
- .nlattr_to_tuple = nf_ct_port_nlattr_to_tuple,
- .nla_policy = nf_ct_port_nla_policy,
- #endif
- #ifdef CONFIG_NF_CONNTRACK_TIMEOUT
- .ctnl_timeout = {
- .nlattr_to_obj = sctp_timeout_nlattr_to_obj,
- .obj_to_nlattr = sctp_timeout_obj_to_nlattr,
- .nlattr_max = CTA_TIMEOUT_SCTP_MAX,
- .obj_size = sizeof(unsigned int) * SCTP_CONNTRACK_MAX,
- .nla_policy = sctp_timeout_nla_policy,
- },
- #endif /* CONFIG_NF_CONNTRACK_TIMEOUT */
- };
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