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flow.c
1482 lines (1272 loc) · 49 KB
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flow.c
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/* Copyright (C) 2007-2013 Open Information Security Foundation
*
* You can copy, redistribute or modify this Program under the terms of
* the GNU General Public License version 2 as published by the Free
* Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* version 2 along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
* 02110-1301, USA.
*/
/**
* \file
*
* \author Victor Julien <victor@inliniac.net>
*
* Flow implementation.
*/
#include "suricata-common.h"
#include "suricata.h"
#include "decode.h"
#include "conf.h"
#include "threadvars.h"
#include "tm-threads.h"
#include "runmodes.h"
#include "util-random.h"
#include "util-time.h"
#include "flow.h"
#include "flow-queue.h"
#include "flow-hash.h"
#include "flow-util.h"
#include "flow-var.h"
#include "flow-private.h"
#include "flow-timeout.h"
#include "flow-manager.h"
#include "flow-storage.h"
#include "flow-bypass.h"
#include "flow-spare-pool.h"
#include "stream-tcp-private.h"
#include "stream-tcp-reassemble.h"
#include "stream-tcp.h"
#include "util-unittest.h"
#include "util-unittest-helper.h"
#include "util-byte.h"
#include "util-misc.h"
#include "util-macset.h"
#include "util-debug.h"
#include "util-privs.h"
#include "util-validate.h"
#include "detect.h"
#include "detect-engine-state.h"
#include "stream.h"
#include "app-layer-parser.h"
#include "app-layer-expectation.h"
#define FLOW_DEFAULT_EMERGENCY_RECOVERY 30
//#define FLOW_DEFAULT_HASHSIZE 262144
#define FLOW_DEFAULT_HASHSIZE 65536
//#define FLOW_DEFAULT_MEMCAP 128 * 1024 * 1024 /* 128 MB */
#define FLOW_DEFAULT_MEMCAP (32 * 1024 * 1024) /* 32 MB */
#define FLOW_DEFAULT_PREALLOC 10000
SC_ATOMIC_DECLARE(FlowProtoTimeoutPtr, flow_timeouts);
/** atomic int that is used when freeing a flow from the hash. In this
* case we walk the hash to find a flow to free. This var records where
* we left off in the hash. Without this only the top rows of the hash
* are freed. This isn't just about fairness. Under severe presure, the
* hash rows on top would be all freed and the time to find a flow to
* free increased with every run. */
SC_ATOMIC_DECLARE(unsigned int, flow_prune_idx);
/** atomic flags */
SC_ATOMIC_DECLARE(unsigned int, flow_flags);
/** FlowProto specific timeouts and free/state functions */
FlowProtoTimeout flow_timeouts_normal[FLOW_PROTO_MAX];
FlowProtoTimeout flow_timeouts_emerg[FLOW_PROTO_MAX];
FlowProtoTimeout flow_timeouts_delta[FLOW_PROTO_MAX];
FlowProtoFreeFunc flow_freefuncs[FLOW_PROTO_MAX];
FlowConfig flow_config;
/** flow memuse counter (atomic), for enforcing memcap limit */
SC_ATOMIC_DECLARE(uint64_t, flow_memuse);
void FlowRegisterTests(void);
void FlowInitFlowProto(void);
int FlowSetProtoFreeFunc(uint8_t, void (*Free)(void *));
/* Run mode selected at suricata.c */
extern int run_mode;
/**
* \brief Update memcap value
*
* \param size new memcap value
*/
int FlowSetMemcap(uint64_t size)
{
if ((uint64_t)SC_ATOMIC_GET(flow_memuse) < size) {
SC_ATOMIC_SET(flow_config.memcap, size);
return 1;
}
return 0;
}
/**
* \brief Return memcap value
*
* \retval memcap value
*/
uint64_t FlowGetMemcap(void)
{
uint64_t memcapcopy = SC_ATOMIC_GET(flow_config.memcap);
return memcapcopy;
}
uint64_t FlowGetMemuse(void)
{
uint64_t memusecopy = SC_ATOMIC_GET(flow_memuse);
return memusecopy;
}
void FlowCleanupAppLayer(Flow *f)
{
if (f == NULL || f->proto == 0)
return;
AppLayerParserStateCleanup(f, f->alstate, f->alparser);
f->alstate = NULL;
f->alparser = NULL;
return;
}
/** \brief Set the IPOnly scanned flag for 'direction'.
*
* \param f Flow to set the flag in
* \param direction direction to set the flag in
*/
void FlowSetIPOnlyFlag(Flow *f, int direction)
{
direction ? (f->flags |= FLOW_TOSERVER_IPONLY_SET) :
(f->flags |= FLOW_TOCLIENT_IPONLY_SET);
return;
}
/** \brief Set flag to indicate that flow has alerts
*
* \param f flow
*/
void FlowSetHasAlertsFlag(Flow *f)
{
f->flags |= FLOW_HAS_ALERTS;
}
/** \brief Check if flow has alerts
*
* \param f flow
* \retval 1 has alerts
* \retval 0 has not alerts
*/
int FlowHasAlerts(const Flow *f)
{
if (f->flags & FLOW_HAS_ALERTS) {
return 1;
}
return 0;
}
bool FlowHasGaps(const Flow *f, uint8_t way)
{
if (f->proto == IPPROTO_TCP) {
TcpSession *ssn = (TcpSession *)f->protoctx;
if (ssn != NULL) {
if (way == STREAM_TOCLIENT) {
if (ssn->server.flags & STREAMTCP_STREAM_FLAG_HAS_GAP)
return 1;
} else {
if (ssn->client.flags & STREAMTCP_STREAM_FLAG_HAS_GAP)
return 1;
}
}
}
return 0;
}
/** \brief Set flag to indicate to change proto for the flow
*
* \param f flow
*/
void FlowSetChangeProtoFlag(Flow *f)
{
f->flags |= FLOW_CHANGE_PROTO;
}
/** \brief Unset flag to indicate to change proto for the flow
*
* \param f flow
*/
void FlowUnsetChangeProtoFlag(Flow *f)
{
f->flags &= ~FLOW_CHANGE_PROTO;
}
/** \brief Check if change proto flag is set for flow
* \param f flow
* \retval 1 change proto flag is set
* \retval 0 change proto flag is not set
*/
int FlowChangeProto(Flow *f)
{
if (f->flags & FLOW_CHANGE_PROTO) {
return 1;
}
return 0;
}
static inline void FlowSwapFlags(Flow *f)
{
SWAP_FLAGS(f->flags, FLOW_TO_SRC_SEEN, FLOW_TO_DST_SEEN);
SWAP_FLAGS(f->flags, FLOW_TOSERVER_IPONLY_SET, FLOW_TOCLIENT_IPONLY_SET);
SWAP_FLAGS(f->flags, FLOW_SGH_TOSERVER, FLOW_SGH_TOCLIENT);
SWAP_FLAGS(f->flags, FLOW_TOSERVER_DROP_LOGGED, FLOW_TOCLIENT_DROP_LOGGED);
SWAP_FLAGS(f->flags, FLOW_TS_PM_ALPROTO_DETECT_DONE, FLOW_TC_PM_ALPROTO_DETECT_DONE);
SWAP_FLAGS(f->flags, FLOW_TS_PP_ALPROTO_DETECT_DONE, FLOW_TC_PP_ALPROTO_DETECT_DONE);
SWAP_FLAGS(f->flags, FLOW_TS_PE_ALPROTO_DETECT_DONE, FLOW_TC_PE_ALPROTO_DETECT_DONE);
SWAP_FLAGS(f->flags, FLOW_PROTO_DETECT_TS_DONE, FLOW_PROTO_DETECT_TC_DONE);
}
static inline void FlowSwapFileFlags(Flow *f)
{
SWAP_FLAGS(f->file_flags, FLOWFILE_NO_MAGIC_TS, FLOWFILE_NO_MAGIC_TC);
SWAP_FLAGS(f->file_flags, FLOWFILE_NO_STORE_TS, FLOWFILE_NO_STORE_TC);
SWAP_FLAGS(f->file_flags, FLOWFILE_NO_MD5_TS, FLOWFILE_NO_MD5_TC);
SWAP_FLAGS(f->file_flags, FLOWFILE_NO_SHA1_TS, FLOWFILE_NO_SHA1_TC);
SWAP_FLAGS(f->file_flags, FLOWFILE_NO_SHA256_TS, FLOWFILE_NO_SHA256_TC);
SWAP_FLAGS(f->file_flags, FLOWFILE_NO_SIZE_TS, FLOWFILE_NO_SIZE_TC);
}
static inline void TcpStreamFlowSwap(Flow *f)
{
TcpSession *ssn = f->protoctx;
SWAP_VARS(TcpStream, ssn->server, ssn->client);
if (ssn->data_first_seen_dir & STREAM_TOSERVER) {
ssn->data_first_seen_dir = STREAM_TOCLIENT;
} else if (ssn->data_first_seen_dir & STREAM_TOCLIENT) {
ssn->data_first_seen_dir = STREAM_TOSERVER;
}
}
/** \brief swap the flow's direction
* \note leaves the 'header' untouched. Interpret that based
* on FLOW_DIR_REVERSED flag.
* \warning: only valid before applayer parsing started. This
* function doesn't swap anything in Flow::alparser,
* Flow::alstate
*/
void FlowSwap(Flow *f)
{
f->flags |= FLOW_DIR_REVERSED;
SWAP_VARS(uint32_t, f->probing_parser_toserver_alproto_masks,
f->probing_parser_toclient_alproto_masks);
FlowSwapFlags(f);
FlowSwapFileFlags(f);
if (f->proto == IPPROTO_TCP) {
TcpStreamFlowSwap(f);
}
SWAP_VARS(AppProto, f->alproto_ts, f->alproto_tc);
SWAP_VARS(uint8_t, f->min_ttl_toserver, f->max_ttl_toserver);
SWAP_VARS(uint8_t, f->min_ttl_toclient, f->max_ttl_toclient);
/* not touching Flow::alparser and Flow::alstate */
SWAP_VARS(const void *, f->sgh_toclient, f->sgh_toserver);
SWAP_VARS(uint32_t, f->todstpktcnt, f->tosrcpktcnt);
SWAP_VARS(uint64_t, f->todstbytecnt, f->tosrcbytecnt);
}
/**
* \brief determine the direction of the packet compared to the flow
* \retval 0 to_server
* \retval 1 to_client
*/
int FlowGetPacketDirection(const Flow *f, const Packet *p)
{
const int reverse = (f->flags & FLOW_DIR_REVERSED) != 0;
if (p->proto == IPPROTO_TCP || p->proto == IPPROTO_UDP || p->proto == IPPROTO_SCTP) {
if (!(CMP_PORT(p->sp,p->dp))) {
/* update flags and counters */
if (CMP_PORT(f->sp,p->sp)) {
return TOSERVER ^ reverse;
} else {
return TOCLIENT ^ reverse;
}
} else {
if (CMP_ADDR(&f->src,&p->src)) {
return TOSERVER ^ reverse;
} else {
return TOCLIENT ^ reverse;
}
}
} else if (p->proto == IPPROTO_ICMP || p->proto == IPPROTO_ICMPV6) {
if (CMP_ADDR(&f->src,&p->src)) {
return TOSERVER ^ reverse;
} else {
return TOCLIENT ^ reverse;
}
}
/* default to toserver */
return TOSERVER;
}
/**
* \brief Check to update "seen" flags
*
* \param p packet
*
* \retval 1 true
* \retval 0 false
*/
static inline int FlowUpdateSeenFlag(const Packet *p)
{
if (PKT_IS_ICMPV4(p)) {
if (ICMPV4_IS_ERROR_MSG(p)) {
return 0;
}
}
return 1;
}
static inline void FlowUpdateTtlTS(Flow *f, Packet *p, uint8_t ttl)
{
if (f->min_ttl_toserver == 0) {
f->min_ttl_toserver = ttl;
} else {
f->min_ttl_toserver = MIN(f->min_ttl_toserver, ttl);
}
f->max_ttl_toserver = MAX(f->max_ttl_toserver, ttl);
}
static inline void FlowUpdateTtlTC(Flow *f, Packet *p, uint8_t ttl)
{
if (f->min_ttl_toclient == 0) {
f->min_ttl_toclient = ttl;
} else {
f->min_ttl_toclient = MIN(f->min_ttl_toclient, ttl);
}
f->max_ttl_toclient = MAX(f->max_ttl_toclient, ttl);
}
static inline void FlowUpdateEthernet(ThreadVars *tv, DecodeThreadVars *dtv,
Flow *f, EthernetHdr *ethh, bool toserver)
{
if (ethh && MacSetFlowStorageEnabled()) {
MacSet *ms = FlowGetStorageById(f, MacSetGetFlowStorageID());
if (ms != NULL) {
if (toserver) {
MacSetAddWithCtr(ms, ethh->eth_src, ethh->eth_dst, tv,
dtv->counter_max_mac_addrs_src,
dtv->counter_max_mac_addrs_dst);
} else {
MacSetAddWithCtr(ms, ethh->eth_dst, ethh->eth_src, tv,
dtv->counter_max_mac_addrs_dst,
dtv->counter_max_mac_addrs_src);
}
}
}
}
/** \brief Update Packet and Flow
*
* Updates packet and flow based on the new packet.
*
* \param f locked flow
* \param p packet
*
* \note overwrites p::flowflags
*/
void FlowHandlePacketUpdate(Flow *f, Packet *p, ThreadVars *tv, DecodeThreadVars *dtv)
{
SCLogDebug("packet %"PRIu64" -- flow %p", p->pcap_cnt, f);
const int pkt_dir = FlowGetPacketDirection(f, p);
#ifdef CAPTURE_OFFLOAD
int state = f->flow_state;
if (state != FLOW_STATE_CAPTURE_BYPASSED) {
#endif
/* update the last seen timestamp of this flow */
if (timercmp(&p->ts, &f->lastts, >)) {
COPY_TIMESTAMP(&p->ts, &f->lastts);
const uint32_t timeout_at = (uint32_t)f->lastts.tv_sec + f->timeout_policy;
if (timeout_at != f->timeout_at) {
f->timeout_at = timeout_at;
}
}
#ifdef CAPTURE_OFFLOAD
} else {
/* still seeing packet, we downgrade to local bypass */
if (p->ts.tv_sec - f->lastts.tv_sec > FLOW_BYPASSED_TIMEOUT / 2) {
SCLogDebug("Downgrading flow to local bypass");
COPY_TIMESTAMP(&p->ts, &f->lastts);
FlowUpdateState(f, FLOW_STATE_LOCAL_BYPASSED);
} else {
/* In IPS mode the packet could come from the other interface so it would
* need to be bypassed */
if (EngineModeIsIPS()) {
BypassedFlowUpdate(f, p);
}
}
}
#endif
/* update flags and counters */
if (pkt_dir == TOSERVER) {
f->todstpktcnt++;
f->todstbytecnt += GET_PKT_LEN(p);
p->flowflags = FLOW_PKT_TOSERVER;
if (!(f->flags & FLOW_TO_DST_SEEN)) {
if (FlowUpdateSeenFlag(p)) {
f->flags |= FLOW_TO_DST_SEEN;
p->flowflags |= FLOW_PKT_TOSERVER_FIRST;
}
}
/* xfer proto detect ts flag to first packet in ts dir */
if (f->flags & FLOW_PROTO_DETECT_TS_DONE) {
f->flags &= ~FLOW_PROTO_DETECT_TS_DONE;
p->flags |= PKT_PROTO_DETECT_TS_DONE;
}
FlowUpdateEthernet(tv, dtv, f, p->ethh, true);
/* update flow's ttl fields if needed */
if (PKT_IS_IPV4(p)) {
FlowUpdateTtlTS(f, p, IPV4_GET_IPTTL(p));
} else if (PKT_IS_IPV6(p)) {
FlowUpdateTtlTS(f, p, IPV6_GET_HLIM(p));
}
} else {
f->tosrcpktcnt++;
f->tosrcbytecnt += GET_PKT_LEN(p);
p->flowflags = FLOW_PKT_TOCLIENT;
if (!(f->flags & FLOW_TO_SRC_SEEN)) {
if (FlowUpdateSeenFlag(p)) {
f->flags |= FLOW_TO_SRC_SEEN;
p->flowflags |= FLOW_PKT_TOCLIENT_FIRST;
}
}
/* xfer proto detect tc flag to first packet in tc dir */
if (f->flags & FLOW_PROTO_DETECT_TC_DONE) {
f->flags &= ~FLOW_PROTO_DETECT_TC_DONE;
p->flags |= PKT_PROTO_DETECT_TC_DONE;
}
FlowUpdateEthernet(tv, dtv, f, p->ethh, false);
/* update flow's ttl fields if needed */
if (PKT_IS_IPV4(p)) {
FlowUpdateTtlTC(f, p, IPV4_GET_IPTTL(p));
} else if (PKT_IS_IPV6(p)) {
FlowUpdateTtlTC(f, p, IPV6_GET_HLIM(p));
}
}
if (f->flow_state == FLOW_STATE_ESTABLISHED) {
SCLogDebug("pkt %p FLOW_PKT_ESTABLISHED", p);
p->flowflags |= FLOW_PKT_ESTABLISHED;
} else if (f->proto == IPPROTO_TCP) {
TcpSession *ssn = (TcpSession *)f->protoctx;
if (ssn != NULL && ssn->state >= TCP_ESTABLISHED) {
p->flowflags |= FLOW_PKT_ESTABLISHED;
}
} else if ((f->flags & (FLOW_TO_DST_SEEN|FLOW_TO_SRC_SEEN)) ==
(FLOW_TO_DST_SEEN|FLOW_TO_SRC_SEEN)) {
SCLogDebug("pkt %p FLOW_PKT_ESTABLISHED", p);
p->flowflags |= FLOW_PKT_ESTABLISHED;
FlowUpdateState(f, FLOW_STATE_ESTABLISHED);
}
/*set the detection bypass flags*/
if (f->flags & FLOW_NOPACKET_INSPECTION) {
SCLogDebug("setting FLOW_NOPACKET_INSPECTION flag on flow %p", f);
DecodeSetNoPacketInspectionFlag(p);
}
if (f->flags & FLOW_NOPAYLOAD_INSPECTION) {
SCLogDebug("setting FLOW_NOPAYLOAD_INSPECTION flag on flow %p", f);
DecodeSetNoPayloadInspectionFlag(p);
}
}
/** \brief Entry point for packet flow handling
*
* This is called for every packet.
*
* \param tv threadvars
* \param dtv decode thread vars (for flow output api thread data)
* \param p packet to handle flow for
*/
void FlowHandlePacket(ThreadVars *tv, FlowLookupStruct *fls, Packet *p)
{
/* Get this packet's flow from the hash. FlowHandlePacket() will setup
* a new flow if nescesary. If we get NULL, we're out of flow memory.
* The returned flow is locked. */
Flow *f = FlowGetFlowFromHash(tv, fls, p, &p->flow);
if (f == NULL)
return;
/* set the flow in the packet */
p->flags |= PKT_HAS_FLOW;
return;
}
/** \brief initialize the configuration
* \warning Not thread safe */
void FlowInitConfig(bool quiet)
{
SCLogDebug("initializing flow engine...");
memset(&flow_config, 0, sizeof(flow_config));
SC_ATOMIC_INIT(flow_flags);
SC_ATOMIC_INIT(flow_memuse);
SC_ATOMIC_INIT(flow_prune_idx);
SC_ATOMIC_INIT(flow_config.memcap);
FlowQueueInit(&flow_recycle_q);
/* set defaults */
flow_config.hash_rand = (uint32_t)RandomGet();
flow_config.hash_size = FLOW_DEFAULT_HASHSIZE;
flow_config.prealloc = FLOW_DEFAULT_PREALLOC;
SC_ATOMIC_SET(flow_config.memcap, FLOW_DEFAULT_MEMCAP);
/* If we have specific config, overwrite the defaults with them,
* otherwise, leave the default values */
intmax_t val = 0;
if (ConfGetInt("flow.emergency-recovery", &val) == 1) {
if (val <= 100 && val >= 1) {
flow_config.emergency_recovery = (uint8_t)val;
} else {
SCLogError(SC_ERR_INVALID_VALUE, "flow.emergency-recovery must be in the range of "
"1 and 100 (as percentage)");
flow_config.emergency_recovery = FLOW_DEFAULT_EMERGENCY_RECOVERY;
}
} else {
SCLogDebug("flow.emergency-recovery, using default value");
flow_config.emergency_recovery = FLOW_DEFAULT_EMERGENCY_RECOVERY;
}
/* Check if we have memcap and hash_size defined at config */
const char *conf_val;
uint32_t configval = 0;
/** set config values for memcap, prealloc and hash_size */
uint64_t flow_memcap_copy = 0;
if ((ConfGet("flow.memcap", &conf_val)) == 1)
{
if (conf_val == NULL) {
FatalError(SC_ERR_FATAL, "Invalid value for flow.memcap: NULL");
}
if (ParseSizeStringU64(conf_val, &flow_memcap_copy) < 0) {
SCLogError(SC_ERR_SIZE_PARSE, "Error parsing flow.memcap "
"from conf file - %s. Killing engine",
conf_val);
exit(EXIT_FAILURE);
} else {
SC_ATOMIC_SET(flow_config.memcap, flow_memcap_copy);
}
}
if ((ConfGet("flow.hash-size", &conf_val)) == 1)
{
if (conf_val == NULL) {
FatalError(SC_ERR_FATAL, "Invalid value for flow.hash-size: NULL");
}
if (StringParseUint32(&configval, 10, strlen(conf_val),
conf_val) > 0) {
flow_config.hash_size = configval;
}
}
if ((ConfGet("flow.prealloc", &conf_val)) == 1)
{
if (conf_val == NULL) {
FatalError(SC_ERR_FATAL, "Invalid value for flow.prealloc: NULL");
}
if (StringParseUint32(&configval, 10, strlen(conf_val),
conf_val) > 0) {
flow_config.prealloc = configval;
}
}
flow_config.memcap_policy = ExceptionPolicyParse("flow.memcap-policy", false);
SCLogDebug("Flow config from suricata.yaml: memcap: %"PRIu64", hash-size: "
"%"PRIu32", prealloc: %"PRIu32, SC_ATOMIC_GET(flow_config.memcap),
flow_config.hash_size, flow_config.prealloc);
/* alloc hash memory */
uint64_t hash_size = flow_config.hash_size * sizeof(FlowBucket);
if (!(FLOW_CHECK_MEMCAP(hash_size))) {
SCLogError(SC_ERR_FLOW_INIT, "allocating flow hash failed: "
"max flow memcap is smaller than projected hash size. "
"Memcap: %"PRIu64", Hash table size %"PRIu64". Calculate "
"total hash size by multiplying \"flow.hash-size\" with %"PRIuMAX", "
"which is the hash bucket size.", SC_ATOMIC_GET(flow_config.memcap), hash_size,
(uintmax_t)sizeof(FlowBucket));
exit(EXIT_FAILURE);
}
flow_hash = SCMallocAligned(flow_config.hash_size * sizeof(FlowBucket), CLS);
if (unlikely(flow_hash == NULL)) {
FatalError(SC_ERR_FATAL,
"Fatal error encountered in FlowInitConfig. Exiting...");
}
memset(flow_hash, 0, flow_config.hash_size * sizeof(FlowBucket));
uint32_t i = 0;
for (i = 0; i < flow_config.hash_size; i++) {
FBLOCK_INIT(&flow_hash[i]);
SC_ATOMIC_INIT(flow_hash[i].next_ts);
}
(void) SC_ATOMIC_ADD(flow_memuse, (flow_config.hash_size * sizeof(FlowBucket)));
if (!quiet) {
SCLogConfig("allocated %"PRIu64" bytes of memory for the flow hash... "
"%" PRIu32 " buckets of size %" PRIuMAX "",
SC_ATOMIC_GET(flow_memuse), flow_config.hash_size,
(uintmax_t)sizeof(FlowBucket));
}
FlowSparePoolInit();
if (!quiet) {
SCLogConfig("flow memory usage: %"PRIu64" bytes, maximum: %"PRIu64,
SC_ATOMIC_GET(flow_memuse), SC_ATOMIC_GET(flow_config.memcap));
}
FlowInitFlowProto();
uint32_t sz = sizeof(Flow) + FlowStorageSize();
SCLogConfig("flow size %u, memcap allows for %" PRIu64 " flows. Per hash row in perfect "
"conditions %" PRIu64,
sz, flow_memcap_copy / sz, (flow_memcap_copy / sz) / flow_config.hash_size);
return;
}
void FlowReset(void)
{
// resets the flows (for reuse by fuzzing)
for (uint32_t u = 0; u < flow_config.hash_size; u++) {
Flow *f = flow_hash[u].head;
while (f) {
Flow *n = f->next;
uint8_t proto_map = FlowGetProtoMapping(f->proto);
FlowClearMemory(f, proto_map);
FlowFree(f);
f = n;
}
flow_hash[u].head = NULL;
}
}
/** \brief shutdown the flow engine
* \warning Not thread safe */
void FlowShutdown(void)
{
Flow *f;
while ((f = FlowDequeue(&flow_recycle_q))) {
FlowFree(f);
}
/* clear and free the hash */
if (flow_hash != NULL) {
/* clean up flow mutexes */
for (uint32_t u = 0; u < flow_config.hash_size; u++) {
f = flow_hash[u].head;
while (f) {
DEBUG_VALIDATE_BUG_ON(f->use_cnt != 0);
Flow *n = f->next;
uint8_t proto_map = FlowGetProtoMapping(f->proto);
FlowClearMemory(f, proto_map);
FlowFree(f);
f = n;
}
f = flow_hash[u].evicted;
while (f) {
DEBUG_VALIDATE_BUG_ON(f->use_cnt != 0);
Flow *n = f->next;
uint8_t proto_map = FlowGetProtoMapping(f->proto);
FlowClearMemory(f, proto_map);
FlowFree(f);
f = n;
}
FBLOCK_DESTROY(&flow_hash[u]);
}
SCFreeAligned(flow_hash);
flow_hash = NULL;
}
(void) SC_ATOMIC_SUB(flow_memuse, flow_config.hash_size * sizeof(FlowBucket));
FlowQueueDestroy(&flow_recycle_q);
FlowSparePoolDestroy();
return;
}
/**
* \brief Function to set the default timeout, free function and flow state
* function for all supported flow_proto.
*/
void FlowInitFlowProto(void)
{
FlowTimeoutsInit();
#define SET_DEFAULTS(p, n, e, c, b, ne, ee, ce, be) \
flow_timeouts_normal[(p)].new_timeout = (n); \
flow_timeouts_normal[(p)].est_timeout = (e); \
flow_timeouts_normal[(p)].closed_timeout = (c); \
flow_timeouts_normal[(p)].bypassed_timeout = (b); \
flow_timeouts_emerg[(p)].new_timeout = (ne); \
flow_timeouts_emerg[(p)].est_timeout = (ee); \
flow_timeouts_emerg[(p)].closed_timeout = (ce); \
flow_timeouts_emerg[(p)].bypassed_timeout = (be); \
SET_DEFAULTS(FLOW_PROTO_DEFAULT,
FLOW_DEFAULT_NEW_TIMEOUT, FLOW_DEFAULT_EST_TIMEOUT,
0, FLOW_DEFAULT_BYPASSED_TIMEOUT,
FLOW_DEFAULT_EMERG_NEW_TIMEOUT, FLOW_DEFAULT_EMERG_EST_TIMEOUT,
0, FLOW_DEFAULT_EMERG_BYPASSED_TIMEOUT);
SET_DEFAULTS(FLOW_PROTO_TCP,
FLOW_IPPROTO_TCP_NEW_TIMEOUT, FLOW_IPPROTO_TCP_EST_TIMEOUT,
FLOW_IPPROTO_TCP_CLOSED_TIMEOUT, FLOW_IPPROTO_TCP_BYPASSED_TIMEOUT,
FLOW_IPPROTO_TCP_EMERG_NEW_TIMEOUT, FLOW_IPPROTO_TCP_EMERG_EST_TIMEOUT,
FLOW_IPPROTO_TCP_EMERG_CLOSED_TIMEOUT, FLOW_DEFAULT_EMERG_BYPASSED_TIMEOUT);
SET_DEFAULTS(FLOW_PROTO_UDP,
FLOW_IPPROTO_UDP_NEW_TIMEOUT, FLOW_IPPROTO_UDP_EST_TIMEOUT,
0, FLOW_IPPROTO_UDP_BYPASSED_TIMEOUT,
FLOW_IPPROTO_UDP_EMERG_NEW_TIMEOUT, FLOW_IPPROTO_UDP_EMERG_EST_TIMEOUT,
0, FLOW_DEFAULT_EMERG_BYPASSED_TIMEOUT);
SET_DEFAULTS(FLOW_PROTO_ICMP,
FLOW_IPPROTO_ICMP_NEW_TIMEOUT, FLOW_IPPROTO_ICMP_EST_TIMEOUT,
0, FLOW_IPPROTO_ICMP_BYPASSED_TIMEOUT,
FLOW_IPPROTO_ICMP_EMERG_NEW_TIMEOUT, FLOW_IPPROTO_ICMP_EMERG_EST_TIMEOUT,
0, FLOW_DEFAULT_EMERG_BYPASSED_TIMEOUT);
flow_freefuncs[FLOW_PROTO_DEFAULT].Freefunc = NULL;
flow_freefuncs[FLOW_PROTO_TCP].Freefunc = NULL;
flow_freefuncs[FLOW_PROTO_UDP].Freefunc = NULL;
flow_freefuncs[FLOW_PROTO_ICMP].Freefunc = NULL;
/* Let's see if we have custom timeouts defined from config */
const char *new = NULL;
const char *established = NULL;
const char *closed = NULL;
const char *bypassed = NULL;
const char *emergency_new = NULL;
const char *emergency_established = NULL;
const char *emergency_closed = NULL;
const char *emergency_bypassed = NULL;
ConfNode *flow_timeouts = ConfGetNode("flow-timeouts");
if (flow_timeouts != NULL) {
ConfNode *proto = NULL;
uint32_t configval = 0;
/* Defaults. */
proto = ConfNodeLookupChild(flow_timeouts, "default");
if (proto != NULL) {
new = ConfNodeLookupChildValue(proto, "new");
established = ConfNodeLookupChildValue(proto, "established");
closed = ConfNodeLookupChildValue(proto, "closed");
bypassed = ConfNodeLookupChildValue(proto, "bypassed");
emergency_new = ConfNodeLookupChildValue(proto, "emergency-new");
emergency_established = ConfNodeLookupChildValue(proto,
"emergency-established");
emergency_closed = ConfNodeLookupChildValue(proto,
"emergency-closed");
emergency_bypassed = ConfNodeLookupChildValue(proto,
"emergency-bypassed");
if (new != NULL &&
StringParseUint32(&configval, 10, strlen(new), new) > 0) {
flow_timeouts_normal[FLOW_PROTO_DEFAULT].new_timeout = configval;
}
if (established != NULL &&
StringParseUint32(&configval, 10, strlen(established),
established) > 0) {
flow_timeouts_normal[FLOW_PROTO_DEFAULT].est_timeout = configval;
}
if (closed != NULL &&
StringParseUint32(&configval, 10, strlen(closed),
closed) > 0) {
flow_timeouts_normal[FLOW_PROTO_DEFAULT].closed_timeout = configval;
}
if (bypassed != NULL &&
StringParseUint32(&configval, 10,
strlen(bypassed),
bypassed) > 0) {
flow_timeouts_normal[FLOW_PROTO_DEFAULT].bypassed_timeout = configval;
}
if (emergency_new != NULL &&
StringParseUint32(&configval, 10, strlen(emergency_new),
emergency_new) > 0) {
flow_timeouts_emerg[FLOW_PROTO_DEFAULT].new_timeout = configval;
}
if (emergency_established != NULL &&
StringParseUint32(&configval, 10,
strlen(emergency_established),
emergency_established) > 0) {
flow_timeouts_emerg[FLOW_PROTO_DEFAULT].est_timeout= configval;
}
if (emergency_closed != NULL &&
StringParseUint32(&configval, 10,
strlen(emergency_closed),
emergency_closed) > 0) {
flow_timeouts_emerg[FLOW_PROTO_DEFAULT].closed_timeout = configval;
}
if (emergency_bypassed != NULL &&
StringParseUint32(&configval, 10,
strlen(emergency_bypassed),
emergency_bypassed) > 0) {
flow_timeouts_emerg[FLOW_PROTO_DEFAULT].bypassed_timeout = configval;
}
}
/* TCP. */
proto = ConfNodeLookupChild(flow_timeouts, "tcp");
if (proto != NULL) {
new = ConfNodeLookupChildValue(proto, "new");
established = ConfNodeLookupChildValue(proto, "established");
closed = ConfNodeLookupChildValue(proto, "closed");
bypassed = ConfNodeLookupChildValue(proto, "bypassed");
emergency_new = ConfNodeLookupChildValue(proto, "emergency-new");
emergency_established = ConfNodeLookupChildValue(proto,
"emergency-established");
emergency_closed = ConfNodeLookupChildValue(proto,
"emergency-closed");
emergency_bypassed = ConfNodeLookupChildValue(proto,
"emergency-bypassed");
if (new != NULL &&
StringParseUint32(&configval, 10, strlen(new), new) > 0) {
flow_timeouts_normal[FLOW_PROTO_TCP].new_timeout = configval;
}
if (established != NULL &&
StringParseUint32(&configval, 10, strlen(established),
established) > 0) {
flow_timeouts_normal[FLOW_PROTO_TCP].est_timeout = configval;
}
if (closed != NULL &&
StringParseUint32(&configval, 10, strlen(closed),
closed) > 0) {
flow_timeouts_normal[FLOW_PROTO_TCP].closed_timeout = configval;
}
if (bypassed != NULL &&
StringParseUint32(&configval, 10,
strlen(bypassed),
bypassed) > 0) {
flow_timeouts_normal[FLOW_PROTO_TCP].bypassed_timeout = configval;
}
if (emergency_new != NULL &&
StringParseUint32(&configval, 10, strlen(emergency_new),
emergency_new) > 0) {
flow_timeouts_emerg[FLOW_PROTO_TCP].new_timeout = configval;
}
if (emergency_established != NULL &&
StringParseUint32(&configval, 10,
strlen(emergency_established),
emergency_established) > 0) {
flow_timeouts_emerg[FLOW_PROTO_TCP].est_timeout = configval;
}
if (emergency_closed != NULL &&
StringParseUint32(&configval, 10,
strlen(emergency_closed),
emergency_closed) > 0) {
flow_timeouts_emerg[FLOW_PROTO_TCP].closed_timeout = configval;
}
if (emergency_bypassed != NULL &&
StringParseUint32(&configval, 10,
strlen(emergency_bypassed),
emergency_bypassed) > 0) {
flow_timeouts_emerg[FLOW_PROTO_TCP].bypassed_timeout = configval;
}
}
/* UDP. */
proto = ConfNodeLookupChild(flow_timeouts, "udp");
if (proto != NULL) {
new = ConfNodeLookupChildValue(proto, "new");
established = ConfNodeLookupChildValue(proto, "established");
bypassed = ConfNodeLookupChildValue(proto, "bypassed");
emergency_new = ConfNodeLookupChildValue(proto, "emergency-new");
emergency_established = ConfNodeLookupChildValue(proto,
"emergency-established");
emergency_bypassed = ConfNodeLookupChildValue(proto,
"emergency-bypassed");
if (new != NULL &&
StringParseUint32(&configval, 10, strlen(new), new) > 0) {
flow_timeouts_normal[FLOW_PROTO_UDP].new_timeout = configval;
}
if (established != NULL &&
StringParseUint32(&configval, 10, strlen(established),
established) > 0) {
flow_timeouts_normal[FLOW_PROTO_UDP].est_timeout = configval;
}
if (bypassed != NULL &&
StringParseUint32(&configval, 10,
strlen(bypassed),
bypassed) > 0) {
flow_timeouts_normal[FLOW_PROTO_UDP].bypassed_timeout = configval;
}
if (emergency_new != NULL &&
StringParseUint32(&configval, 10, strlen(emergency_new),
emergency_new) > 0) {
flow_timeouts_emerg[FLOW_PROTO_UDP].new_timeout = configval;
}
if (emergency_established != NULL &&
StringParseUint32(&configval, 10,
strlen(emergency_established),
emergency_established) > 0) {
flow_timeouts_emerg[FLOW_PROTO_UDP].est_timeout = configval;
}
if (emergency_bypassed != NULL &&
StringParseUint32(&configval, 10,
strlen(emergency_bypassed),
emergency_bypassed) > 0) {
flow_timeouts_emerg[FLOW_PROTO_UDP].bypassed_timeout = configval;
}
}
/* ICMP. */
proto = ConfNodeLookupChild(flow_timeouts, "icmp");
if (proto != NULL) {
new = ConfNodeLookupChildValue(proto, "new");
established = ConfNodeLookupChildValue(proto, "established");
bypassed = ConfNodeLookupChildValue(proto, "bypassed");
emergency_new = ConfNodeLookupChildValue(proto, "emergency-new");
emergency_established = ConfNodeLookupChildValue(proto,
"emergency-established");
emergency_bypassed = ConfNodeLookupChildValue(proto,
"emergency-bypassed");
if (new != NULL &&
StringParseUint32(&configval, 10, strlen(new), new) > 0) {
flow_timeouts_normal[FLOW_PROTO_ICMP].new_timeout = configval;
}
if (established != NULL &&
StringParseUint32(&configval, 10, strlen(established),
established) > 0) {
flow_timeouts_normal[FLOW_PROTO_ICMP].est_timeout = configval;