// SPDX-License-Identifier: GPL-2.0-only
|
/*
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* Connection tracking protocol helper module for SCTP.
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*
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* Copyright (c) 2004 Kiran Kumar Immidi <immidi_kiran@yahoo.com>
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* Copyright (c) 2004-2012 Patrick McHardy <kaber@trash.net>
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*
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* SCTP is defined in RFC 2960. References to various sections in this code
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* are to this RFC.
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*/
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#include <linux/types.h>
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#include <linux/timer.h>
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#include <linux/netfilter.h>
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#include <linux/in.h>
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#include <linux/ip.h>
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#include <linux/sctp.h>
|
#include <linux/string.h>
|
#include <linux/seq_file.h>
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#include <linux/spinlock.h>
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#include <linux/interrupt.h>
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#include <net/sctp/checksum.h>
|
|
#include <net/netfilter/nf_log.h>
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#include <net/netfilter/nf_conntrack.h>
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#include <net/netfilter/nf_conntrack_l4proto.h>
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#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",
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"COOKIE_WAIT",
|
"COOKIE_ECHOED",
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"ESTABLISHED",
|
"SHUTDOWN_SENT",
|
"SHUTDOWN_RECD",
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"SHUTDOWN_ACK_SENT",
|
"HEARTBEAT_SENT",
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"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
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#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
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#define sHS SCTP_CONNTRACK_HEARTBEAT_SENT
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#define sHA SCTP_CONNTRACK_HEARTBEAT_ACKED
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#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 */
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/* 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},
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/* shutdown_ack */ {sSA, sCL, sCW, sCE, sES, sSA, sSA, sSA, sSA, sHA},
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/* error */ {sCL, sCL, sCW, sCE, sES, sSS, sSR, sSA, sCL, sHA},/* Can't have Stale cookie*/
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/* cookie_echo */ {sCL, sCL, sCE, sCE, sES, sSS, sSR, sSA, sCL, sHA},/* 5.2.4 - Big TODO */
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/* 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 */
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/* 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},
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/* 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},
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/* 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}
|
}
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};
|
|
#ifdef CONFIG_NF_CONNTRACK_PROCFS
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/* 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 ||
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sch->type == SCTP_CID_COOKIE_ECHO ||
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flag) &&
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count != 0) || !sch->length) {
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pr_debug("Basic checks failed\n");
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return 1;
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}
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|
if (map)
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set_bit(sch->type, map);
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}
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pr_debug("Basic checks passed\n");
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return count == 0;
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}
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|
static int sctp_new_state(enum ip_conntrack_dir dir,
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enum sctp_conntrack cur_state,
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int chunk_type)
|
{
|
int i;
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|
pr_debug("Chunk type: %d\n", chunk_type);
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|
switch (chunk_type) {
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case SCTP_CID_INIT:
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pr_debug("SCTP_CID_INIT\n");
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i = 0;
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break;
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case SCTP_CID_INIT_ACK:
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pr_debug("SCTP_CID_INIT_ACK\n");
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i = 1;
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break;
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case SCTP_CID_ABORT:
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pr_debug("SCTP_CID_ABORT\n");
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i = 2;
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break;
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case SCTP_CID_SHUTDOWN:
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pr_debug("SCTP_CID_SHUTDOWN\n");
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i = 3;
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break;
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case SCTP_CID_SHUTDOWN_ACK:
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pr_debug("SCTP_CID_SHUTDOWN_ACK\n");
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i = 4;
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break;
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case SCTP_CID_ERROR:
|
pr_debug("SCTP_CID_ERROR\n");
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i = 5;
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break;
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case SCTP_CID_COOKIE_ECHO:
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pr_debug("SCTP_CID_COOKIE_ECHO\n");
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i = 6;
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break;
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case SCTP_CID_COOKIE_ACK:
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pr_debug("SCTP_CID_COOKIE_ACK\n");
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i = 7;
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break;
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case SCTP_CID_SHUTDOWN_COMPLETE:
|
pr_debug("SCTP_CID_SHUTDOWN_COMPLETE\n");
|
i = 8;
|
break;
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case SCTP_CID_HEARTBEAT:
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pr_debug("SCTP_CID_HEARTBEAT");
|
i = 9;
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break;
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case SCTP_CID_HEARTBEAT_ACK:
|
pr_debug("SCTP_CID_HEARTBEAT_ACK");
|
i = 10;
|
break;
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default:
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/* 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 */
|
};
|
