blob: 3d719d3eb9a38c7709b8d224facdad8820ebded4 [file] [log] [blame]
/*
* 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.
*
* 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/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 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 */ {sCW, sCW, 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, sCL, 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}
}
};
static inline struct nf_sctp_net *sctp_pernet(struct net *net)
{
return &net->ct.nf_ct_proto.sctp;
}
#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 = new_state;
}
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_make_writable(skb, dataoff + sizeof(struct sctphdr))) {
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. */
static int 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 };
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 ||
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]) {
pr_debug("Verification tag check failed\n");
goto out_unlock;
}
}
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;
}
ct->proto.sctp.state = new_state;
if (old_state != new_state)
nf_conntrack_event_cache(IPCT_PROTOINFO, ct);
}
spin_unlock_bh(&ct->lock);
timeouts = nf_ct_timeout_lookup(ct);
if (!timeouts)
timeouts = 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 | NLA_F_NESTED);
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(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 = sctp_pernet(net);
int i;
/* 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 */
#ifdef CONFIG_SYSCTL
static struct ctl_table sctp_sysctl_table[] = {
{
.procname = "nf_conntrack_sctp_timeout_closed",
.maxlen = sizeof(unsigned int),
.mode = 0644,
.proc_handler = proc_dointvec_jiffies,
},
{
.procname = "nf_conntrack_sctp_timeout_cookie_wait",
.maxlen = sizeof(unsigned int),
.mode = 0644,
.proc_handler = proc_dointvec_jiffies,
},
{
.procname = "nf_conntrack_sctp_timeout_cookie_echoed",
.maxlen = sizeof(unsigned int),
.mode = 0644,
.proc_handler = proc_dointvec_jiffies,
},
{
.procname = "nf_conntrack_sctp_timeout_established",
.maxlen = sizeof(unsigned int),
.mode = 0644,
.proc_handler = proc_dointvec_jiffies,
},
{
.procname = "nf_conntrack_sctp_timeout_shutdown_sent",
.maxlen = sizeof(unsigned int),
.mode = 0644,
.proc_handler = proc_dointvec_jiffies,
},
{
.procname = "nf_conntrack_sctp_timeout_shutdown_recd",
.maxlen = sizeof(unsigned int),
.mode = 0644,
.proc_handler = proc_dointvec_jiffies,
},
{
.procname = "nf_conntrack_sctp_timeout_shutdown_ack_sent",
.maxlen = sizeof(unsigned int),
.mode = 0644,
.proc_handler = proc_dointvec_jiffies,
},
{
.procname = "nf_conntrack_sctp_timeout_heartbeat_sent",
.maxlen = sizeof(unsigned int),
.mode = 0644,
.proc_handler = proc_dointvec_jiffies,
},
{
.procname = "nf_conntrack_sctp_timeout_heartbeat_acked",
.maxlen = sizeof(unsigned int),
.mode = 0644,
.proc_handler = proc_dointvec_jiffies,
},
{ }
};
#endif
static int sctp_kmemdup_sysctl_table(struct nf_proto_net *pn,
struct nf_sctp_net *sn)
{
#ifdef CONFIG_SYSCTL
if (pn->ctl_table)
return 0;
pn->ctl_table = kmemdup(sctp_sysctl_table,
sizeof(sctp_sysctl_table),
GFP_KERNEL);
if (!pn->ctl_table)
return -ENOMEM;
pn->ctl_table[0].data = &sn->timeouts[SCTP_CONNTRACK_CLOSED];
pn->ctl_table[1].data = &sn->timeouts[SCTP_CONNTRACK_COOKIE_WAIT];
pn->ctl_table[2].data = &sn->timeouts[SCTP_CONNTRACK_COOKIE_ECHOED];
pn->ctl_table[3].data = &sn->timeouts[SCTP_CONNTRACK_ESTABLISHED];
pn->ctl_table[4].data = &sn->timeouts[SCTP_CONNTRACK_SHUTDOWN_SENT];
pn->ctl_table[5].data = &sn->timeouts[SCTP_CONNTRACK_SHUTDOWN_RECD];
pn->ctl_table[6].data = &sn->timeouts[SCTP_CONNTRACK_SHUTDOWN_ACK_SENT];
pn->ctl_table[7].data = &sn->timeouts[SCTP_CONNTRACK_HEARTBEAT_SENT];
pn->ctl_table[8].data = &sn->timeouts[SCTP_CONNTRACK_HEARTBEAT_ACKED];
#endif
return 0;
}
static int sctp_init_net(struct net *net)
{
struct nf_sctp_net *sn = sctp_pernet(net);
struct nf_proto_net *pn = &sn->pn;
if (!pn->users) {
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];
}
return sctp_kmemdup_sysctl_table(pn, sn);
}
static struct nf_proto_net *sctp_get_net_proto(struct net *net)
{
return &net->ct.nf_ct_proto.sctp.pn;
}
const struct nf_conntrack_l4proto nf_conntrack_l4proto_sctp = {
.l4proto = IPPROTO_SCTP,
#ifdef CONFIG_NF_CONNTRACK_PROCFS
.print_conntrack = sctp_print_conntrack,
#endif
.packet = sctp_packet,
.can_early_drop = sctp_can_early_drop,
.me = THIS_MODULE,
#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 */
.init_net = sctp_init_net,
.get_net_proto = sctp_get_net_proto,
};