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-rw-r--r--net/netfilter/nf_conntrack_proto_sctp.c730
1 files changed, 730 insertions, 0 deletions
diff --git a/net/netfilter/nf_conntrack_proto_sctp.c b/net/netfilter/nf_conntrack_proto_sctp.c
new file mode 100644
index 000000000..c6bd53398
--- /dev/null
+++ b/net/netfilter/nf_conntrack_proto_sctp.c
@@ -0,0 +1,730 @@
+// 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>
+
+static const char *const sctp_conntrack_names[] = {
+ [SCTP_CONNTRACK_NONE] = "NONE",
+ [SCTP_CONNTRACK_CLOSED] = "CLOSED",
+ [SCTP_CONNTRACK_COOKIE_WAIT] = "COOKIE_WAIT",
+ [SCTP_CONNTRACK_COOKIE_ECHOED] = "COOKIE_ECHOED",
+ [SCTP_CONNTRACK_ESTABLISHED] = "ESTABLISHED",
+ [SCTP_CONNTRACK_SHUTDOWN_SENT] = "SHUTDOWN_SENT",
+ [SCTP_CONNTRACK_SHUTDOWN_RECD] = "SHUTDOWN_RECD",
+ [SCTP_CONNTRACK_SHUTDOWN_ACK_SENT] = "SHUTDOWN_ACK_SENT",
+ [SCTP_CONNTRACK_HEARTBEAT_SENT] = "HEARTBEAT_SENT",
+};
+
+#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] = 210 SECS,
+ [SCTP_CONNTRACK_SHUTDOWN_SENT] = 3 SECS,
+ [SCTP_CONNTRACK_SHUTDOWN_RECD] = 3 SECS,
+ [SCTP_CONNTRACK_SHUTDOWN_ACK_SENT] = 3 SECS,
+ [SCTP_CONNTRACK_HEARTBEAT_SENT] = 30 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 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 direction.
+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.
+*/
+
+/* 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 */
+/* init */ {sCL, sCL, sCW, sCE, sES, sCL, sCL, sSA, sCW},
+/* init_ack */ {sCL, sCL, sCW, sCE, sES, sSS, sSR, sSA, sCL},
+/* abort */ {sCL, sCL, sCL, sCL, sCL, sCL, sCL, sCL, sCL},
+/* shutdown */ {sCL, sCL, sCW, sCE, sSS, sSS, sSR, sSA, sCL},
+/* shutdown_ack */ {sSA, sCL, sCW, sCE, sES, sSA, sSA, sSA, sSA},
+/* error */ {sCL, sCL, sCW, sCE, sES, sSS, sSR, sSA, sCL},/* Can't have Stale cookie*/
+/* cookie_echo */ {sCL, sCL, sCE, sCE, sES, sSS, sSR, sSA, sCL},/* 5.2.4 - Big TODO */
+/* cookie_ack */ {sCL, sCL, sCW, sES, sES, sSS, sSR, sSA, sCL},/* Can't come in orig dir */
+/* shutdown_comp*/ {sCL, sCL, sCW, sCE, sES, sSS, sSR, sCL, sCL},
+/* heartbeat */ {sHS, sCL, sCW, sCE, sES, sSS, sSR, sSA, sHS},
+/* heartbeat_ack*/ {sCL, sCL, sCW, sCE, sES, sSS, sSR, sSA, sHS},
+ },
+ {
+/* REPLY */
+/* sNO, sCL, sCW, sCE, sES, sSS, sSR, sSA, sHS */
+/* init */ {sIV, sCL, sCW, sCE, sES, sSS, sSR, sSA, sIV},/* INIT in sCL Big TODO */
+/* init_ack */ {sIV, sCW, sCW, sCE, sES, sSS, sSR, sSA, sIV},
+/* abort */ {sIV, sCL, sCL, sCL, sCL, sCL, sCL, sCL, sIV},
+/* shutdown */ {sIV, sCL, sCW, sCE, sSR, sSS, sSR, sSA, sIV},
+/* shutdown_ack */ {sIV, sCL, sCW, sCE, sES, sSA, sSA, sSA, sIV},
+/* error */ {sIV, sCL, sCW, sCL, sES, sSS, sSR, sSA, sIV},
+/* cookie_echo */ {sIV, sCL, sCE, sCE, sES, sSS, sSR, sSA, sIV},/* Can't come in reply dir */
+/* cookie_ack */ {sIV, sCL, sCW, sES, sES, sSS, sSR, sSA, sIV},
+/* shutdown_comp*/ {sIV, sCL, sCW, sCE, sES, sSS, sSR, sCL, sIV},
+/* heartbeat */ {sIV, sCL, sCW, sCE, sES, sSS, sSR, sSA, sHS},
+/* heartbeat_ack*/ {sIV, sCL, sCW, sCE, sES, sSS, sSR, sSA, sES},
+ }
+};
+
+#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
+
+/* do_basic_checks ensures sch->length > 0, do not use before */
+#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,
+ const struct nf_hook_state *state)
+{
+ u_int32_t offset, count;
+ struct sctp_chunkhdr _sch, *sch;
+ int flag;
+
+ flag = 0;
+
+ for_each_sctp_chunk (skb, sch, _sch, offset, dataoff, count) {
+ 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) {
+ nf_ct_l4proto_log_invalid(skb, ct, state,
+ "%s failed. chunk num %d, type %d, len %d flag %d\n",
+ __func__, count, sch->type, sch->length, flag);
+ return 1;
+ }
+
+ if (map)
+ set_bit(sch->type, map);
+ }
+
+ return count == 0;
+}
+
+static int sctp_new_state(enum ip_conntrack_dir dir,
+ enum sctp_conntrack cur_state,
+ int chunk_type)
+{
+ int i;
+
+ switch (chunk_type) {
+ case SCTP_CID_INIT:
+ i = 0;
+ break;
+ case SCTP_CID_INIT_ACK:
+ i = 1;
+ break;
+ case SCTP_CID_ABORT:
+ i = 2;
+ break;
+ case SCTP_CID_SHUTDOWN:
+ i = 3;
+ break;
+ case SCTP_CID_SHUTDOWN_ACK:
+ i = 4;
+ break;
+ case SCTP_CID_ERROR:
+ i = 5;
+ break;
+ case SCTP_CID_COOKIE_ECHO:
+ i = 6;
+ break;
+ case SCTP_CID_COOKIE_ACK:
+ i = 7;
+ break;
+ case SCTP_CID_SHUTDOWN_COMPLETE:
+ i = 8;
+ break;
+ case SCTP_CID_HEARTBEAT:
+ i = 9;
+ break;
+ case SCTP_CID_HEARTBEAT_ACK:
+ i = 10;
+ break;
+ default:
+ /* Other chunks like DATA or SACK do not change the state */
+ pr_debug("Unknown chunk type %d, Will stay in %s\n",
+ chunk_type, sctp_conntrack_names[cur_state]);
+ return 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, 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, state) != 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]) {
+ nf_ct_l4proto_log_invalid(skb, ct, state,
+ "verification tag check failed %x vs %x for dir %d",
+ sh->vtag, ct->proto.sctp.vtag[dir], dir);
+ 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) {
+ /* (A) vtag MUST be zero */
+ if (sh->vtag != 0)
+ goto out_unlock;
+ } else if (sch->type == SCTP_CID_ABORT) {
+ /* (B) vtag MUST match own vtag if T flag is unset OR
+ * MUST match peer's vtag if T flag is set
+ */
+ if ((!(sch->flags & SCTP_CHUNK_FLAG_T) &&
+ sh->vtag != ct->proto.sctp.vtag[dir]) ||
+ ((sch->flags & SCTP_CHUNK_FLAG_T) &&
+ sh->vtag != ct->proto.sctp.vtag[!dir]))
+ goto out_unlock;
+ } else if (sch->type == SCTP_CID_SHUTDOWN_COMPLETE) {
+ /* (C) vtag MUST match own vtag if T flag is unset OR
+ * MUST match peer's vtag if T flag is set
+ */
+ if ((!(sch->flags & SCTP_CHUNK_FLAG_T) &&
+ sh->vtag != ct->proto.sctp.vtag[dir]) ||
+ ((sch->flags & SCTP_CHUNK_FLAG_T) &&
+ sh->vtag != ct->proto.sctp.vtag[!dir]))
+ goto out_unlock;
+ } else if (sch->type == SCTP_CID_COOKIE_ECHO) {
+ /* (D) vtag must be same as init_vtag as found in INIT_ACK */
+ if (sh->vtag != ct->proto.sctp.vtag[dir])
+ goto out_unlock;
+ } else if (sch->type == SCTP_CID_COOKIE_ACK) {
+ ct->proto.sctp.init[dir] = 0;
+ ct->proto.sctp.init[!dir] = 0;
+ } 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) {
+ nf_ct_l4proto_log_invalid(skb, ct, state,
+ "Invalid, old_state %d, dir %d, type %d",
+ old_state, dir, sch->type);
+
+ goto out_unlock;
+ }
+
+ /* If it is an INIT or an INIT ACK note down the vtag */
+ if (sch->type == SCTP_CID_INIT) {
+ struct sctp_inithdr _ih, *ih;
+
+ ih = skb_header_pointer(skb, offset + sizeof(_sch), sizeof(*ih), &_ih);
+ if (!ih)
+ goto out_unlock;
+
+ if (ct->proto.sctp.init[dir] && ct->proto.sctp.init[!dir])
+ ct->proto.sctp.init[!dir] = 0;
+ ct->proto.sctp.init[dir] = 1;
+
+ 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;
+ } else if (sch->type == SCTP_CID_INIT_ACK) {
+ struct sctp_inithdr _ih, *ih;
+ __be32 vtag;
+
+ ih = skb_header_pointer(skb, offset + sizeof(_sch), sizeof(*ih), &_ih);
+ if (!ih)
+ goto out_unlock;
+
+ vtag = ct->proto.sctp.vtag[!dir];
+ if (!ct->proto.sctp.init[!dir] && vtag && vtag != ih->init_tag)
+ goto out_unlock;
+ /* collision */
+ if (ct->proto.sctp.init[dir] && ct->proto.sctp.init[!dir] &&
+ vtag != ih->init_tag)
+ goto out_unlock;
+
+ pr_debug("Setting vtag %x for dir %d\n", ih->init_tag, !dir);
+ ct->proto.sctp.vtag[!dir] = ih->init_tag;
+ }
+
+ ct->proto.sctp.state = new_state;
+ if (old_state != new_state) {
+ nf_conntrack_event_cache(IPCT_PROTOINFO, ct);
+ if (new_state == SCTP_CONNTRACK_ESTABLISHED &&
+ !test_and_set_bit(IPS_ASSURED_BIT, &ct->status))
+ nf_conntrack_event_cache(IPCT_ASSURED, 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]);
+
+ 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, bool destroy)
+{
+ 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))
+ goto nla_put_failure;
+
+ if (destroy)
+ goto skip_state;
+
+ if (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;
+
+skip_state:
+ 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 */
+};
generated by cgit v1.2.3 (git 2.39.1) at 2024-05-18 16:56:18 +0000