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suricata/src/defrag.c

2465 lines
61 KiB
C

/* Copyright (c) 2009 Open Information Security Foundation */
/**
* \file
*
* Defragmentation module.
*
* \author Endace Technology Limited, Jason Ish <jason.ish@endace.com>
*
* References:
* - RFC 815
* - OpenBSD PF's IP normalizaton (pf_norm.c)
*
* \todo pool for frag packet storage
* \todo policy bsd-right
* \todo profile hash function
* \todo log anomalies
*/
#include <sys/time.h>
#include "queue.h"
#include "suricata.h"
#include "threads.h"
#include "conf.h"
#include "decode-ipv6.h"
#include "util-hashlist.h"
#include "util-pool.h"
#include "util-time.h"
#include "util-print.h"
#include "util-debug.h"
#include "util-fix_checksum.h"
#include "util-random.h"
#ifdef UNITTESTS
#include "util-unittest.h"
#endif
#define DEFAULT_DEFRAG_HASH_SIZE 0xffff
/**
* Default timeout (in seconds) before a defragmentation tracker will
* be released.
*/
#define TIMEOUT_DEFAULT 60
/**
* Maximum allowed timeout, 24 hours.
*/
#define TIMEOUT_MAX 60 * 60 * 24
/**
* Minimum allowed timeout, 1 second.
*/
#define TIMEOUT_MIN 1
/** Fragment reassembly policies. */
enum defrag_policies {
POLICY_FIRST = 0,
POLICY_LAST,
POLICY_BSD,
POLICY_BSD_RIGHT,
POLICY_LINUX,
POLICY_WINDOWS,
POLICY_SOLARIS,
POLICY_DEFAULT = POLICY_BSD,
};
/**
* A context for an instance of a fragmentation re-assembler, in case
* we ever need more than one.
*/
typedef struct _DefragContext {
uint64_t ip4_frags; /**< Number of IPv4 fragments seen. */
uint64_t ip6_frags; /**< Number of IPv6 fragments seen. */
HashListTable *frag_table; /**< Hash (list) table of fragment trackers. */
SCMutex frag_table_lock;
Pool *tracker_pool; /**< Pool of trackers. */
SCMutex tracker_pool_lock;
Pool *frag_pool; /**< Pool of fragments. */
SCMutex frag_pool_lock;
time_t timeout; /**< Default timeout. */
uint8_t default_policy; /**< Default policy. */
} DefragContext;
/**
* Storage for an individual fragment.
*/
typedef struct _frag {
DefragContext *dc; /**< The defragmentation context this frag was
* allocated under. */
uint16_t offset; /**< The offset of this fragment, already
* multiplied by 8. */
uint16_t len; /**< The length of this fragment. */
uint8_t hlen; /**< The length of this fragments IP header. */
uint8_t more_frags; /**< More frags? */
uint16_t ip_hdr_offset; /**< Offset in the packet where the IP
* header starts. */
uint16_t frag_hdr_offset; /**< Offset in the packet where the frag
* header starts. */
uint16_t data_offset; /**< Offset to the packet data. */
uint16_t data_len; /**< Length of data. */
uint8_t *pkt; /**< The actual packet. */
uint16_t ltrim; /**< Number of leading bytes to trim when
* re-assembling the packet. */
int8_t skip; /**< Skip this fragment during re-assembly. */
TAILQ_ENTRY(_frag) next; /**< Pointer to next fragment for tailq. */
} Frag;
/**
* A defragmentation tracker. Used to track fragments that make up a
* single packet.
*/
typedef struct _DefragTracker {
DefragContext *dc; /**< The defragmentation context this tracker
* was allocated under. */
uint8_t policy; /**< Reassembly policy this tracker will use. */
struct timeval timeout; /**< When this tracker will timeout. */
uint8_t af; /**< Address family for this tracker, AF_INET or
* AF_INET6. */
uint32_t id; /**< IP ID for this tracker. 32 bits for IPv6, 16
* for IPv4. */
Address src_addr; /**< Source address for this tracker. */
Address dst_addr; /**< Destination address for this tracker. */
uint8_t seen_last; /**< Has this tracker seen the last fragment? */
SCMutex lock; /**< Mutex for locking list operations on
* this tracker. */
TAILQ_HEAD(frag_tailq, _frag) frags; /**< Head of list of fragments. */
} DefragTracker;
/** A random value used for hash key generation. */
static int defrag_hash_rand;
/** Hash table size, and also the maximum number of trackers that will
* be allocated. */
static int defrag_hash_size;
/** The global DefragContext so all threads operate from the same
* context. */
static DefragContext *defrag_context;
/**
* Utility/debugging function to dump the frags associated with a
* tracker. Only enable when unit tests are enabled.
*/
#if 0
#ifdef UNITTESTS
static void
DumpFrags(DefragTracker *tracker)
{
Frag *frag;
printf("Dumping frags for packet: ID=%d\n", tracker->id);
TAILQ_FOREACH(frag, &tracker->frags, next) {
printf("-> Frag: frag_offset=%d, frag_len=%d, data_len=%d, ltrim=%d, skip=%d\n", frag->offset, frag->len, frag->data_len, frag->ltrim, frag->skip);
PrintRawDataFp(stdout, frag->pkt, frag->len);
}
}
#endif /* UNITTESTS */
#endif
/**
* Generate a key for looking of a fragtracker in a hash
* table. Adapted from the hash function in flow-hash.c.
*
* \todo Test performance and distribution.
*/
static uint32_t
DefragHashFunc(HashListTable *ht, void *data, uint16_t datalen)
{
DefragTracker *p = (DefragTracker *)data;
uint32_t key;
if (p->af == AF_INET) {
key = (defrag_hash_rand + p->af +
p->src_addr.addr_data32[0] + p->dst_addr.addr_data32[0]) %
defrag_hash_size;
}
else if (p->af == AF_INET6) {
key = (defrag_hash_rand + p->af +
p->src_addr.addr_data32[0] + p->src_addr.addr_data32[1] +
p->src_addr.addr_data32[2] + p->src_addr.addr_data32[3] +
p->dst_addr.addr_data32[0] + p->dst_addr.addr_data32[1] +
p->dst_addr.addr_data32[2] + p->dst_addr.addr_data32[3]) %
defrag_hash_size;
}
else
key = 0;
return key;
}
/**
* \brief Compare 2 DefragTracker nodes in case of hash conflict.
*
* \retval 1 if a and b match, otherwise 0.
*/
static char
DefragHashCompare(void *a, uint16_t a_len, void *b, uint16_t b_len)
{
DefragTracker *dta = (DefragTracker *)a;
DefragTracker *dtb = (DefragTracker *)b;
if (dta->af != dtb->af)
return 0;
else if (dta->id != dtb->id)
return 0;
else if (!CMP_ADDR(&dta->src_addr, &dtb->src_addr))
return 0;
else if (!CMP_ADDR(&dta->dst_addr, &dtb->dst_addr))
return 0;
/* Match. */
return 1;
}
/**
* \brief Called by the hash table when a tracker is removed from the
* hash table.
*
* We don't actually do anything here. The tracker will be reset and
* put back into a memory pool.
*/
static void
DefragHashFree(void *data)
{
}
/**
* \brief Reset a frag for reuse in a pool.
*/
static void
DefragFragReset(Frag *frag)
{
DefragContext *dc = frag->dc;
if (frag->pkt != NULL)
free(frag->pkt);
memset(frag, 0, sizeof(*frag));
frag->dc = dc;
}
/**
* \brief Allocate a new frag for use in a pool.
*/
static void *
DefragFragNew(void *arg)
{
DefragContext *dc = arg;
Frag *frag;
frag = calloc(1, sizeof(*frag));
frag->dc = dc;
return (void *)frag;
}
/**
* \brief Free a frag when released from a pool.
*/
static void
DefragFragFree(void *arg)
{
Frag *frag = arg;
free(frag);
}
/**
* \brief Free all frags associated with a tracker.
*/
static void
DefragTrackerFreeFrags(DefragTracker *tracker)
{
Frag *frag;
/* Lock the frag pool as we'll be return items to it. */
SCMutexLock(&tracker->dc->frag_pool_lock);
while ((frag = TAILQ_FIRST(&tracker->frags)) != NULL) {
TAILQ_REMOVE(&tracker->frags, frag, next);
/* Don't free the frag, just give it back to its pool. */
DefragFragReset(frag);
PoolReturn(frag->dc->frag_pool, frag);
}
SCMutexUnlock(&tracker->dc->frag_pool_lock);
}
/**
* \brief Reset a tracker for reuse.
*/
static void
DefragTrackerReset(DefragTracker *tracker)
{
DefragContext *saved_dc = tracker->dc;
SCMutex saved_lock = tracker->lock;
DefragTrackerFreeFrags(tracker);
memset(tracker, 0, sizeof(*tracker));
tracker->dc = saved_dc;
tracker->lock = saved_lock;
TAILQ_INIT(&tracker->frags);
}
/**
* \brief Allocates a new defragmentation tracker for use in the pool
* for trackers.
*
* \arg Pointer to DefragContext this new tracker will be associated
* with.
*
* \retval A new DefragTracker if successfull, NULL on failure.
*/
static void *
DefragTrackerNew(void *arg)
{
DefragContext *dc = arg;
DefragTracker *tracker;
tracker = calloc(1, sizeof(*tracker));
if (tracker == NULL)
return NULL;
if (SCMutexInit(&tracker->lock, NULL) != 0) {
free(tracker);
return NULL;
}
tracker->dc = dc;
TAILQ_INIT(&tracker->frags);
return (void *)tracker;
}
/**
* \brief Free a defragmentation tracker that is being removed from
* the pool.
*/
static void
DefragTrackerFree(void *arg)
{
DefragTracker *tracker = arg;
SCMutexDestroy(&tracker->lock);
DefragTrackerFreeFrags(tracker);
free(tracker);
}
/**
* \brief Create a new DefragContext.
*
* \retval On success a return an initialized DefragContext, otherwise
* NULL will be returned.
*/
static DefragContext *
DefragContextNew(void)
{
DefragContext *dc;
dc = calloc(1, sizeof(*dc));
if (dc == NULL)
return NULL;
/* Initialize the hash table. */
dc->frag_table = HashListTableInit(DEFAULT_DEFRAG_HASH_SIZE, DefragHashFunc,
DefragHashCompare, DefragHashFree);
if (dc->frag_table == NULL) {
SCLogError(SC_ERR_MEM_ALLOC,
"Defrag: Failed to initialize hash table.");
exit(EXIT_FAILURE);
}
if (SCMutexInit(&dc->frag_table_lock, NULL) != 0) {
SCLogError(SC_ERR_MEM_ALLOC,
"Defrag: Failed to initialize hash table mutex.");
exit(EXIT_FAILURE);
}
/* Initialize the pool of trackers. */
intmax_t tracker_pool_size;
if (!ConfGetInt("defrag.trackers", &tracker_pool_size)) {
tracker_pool_size = DEFAULT_DEFRAG_HASH_SIZE;
}
dc->tracker_pool = PoolInit(tracker_pool_size, tracker_pool_size,
DefragTrackerNew, dc, DefragTrackerFree);
if (dc->tracker_pool == NULL) {
SCLogError(SC_ERR_MEM_ALLOC,
"Defrag: Failed to initialize tracker pool.");
exit(EXIT_FAILURE);
}
if (SCMutexInit(&dc->tracker_pool_lock, NULL) != 0) {
SCLogError(SC_ERR_MUTEX,
"Defrag: Failed to initialize tracker pool mutex.");
exit(EXIT_FAILURE);
}
/* Initialize the pool of frags. */
int frag_pool_size = 0xffff;
int frag_pool_prealloc = frag_pool_size / 4;
dc->frag_pool = PoolInit(frag_pool_size, frag_pool_prealloc,
DefragFragNew, dc, DefragFragFree);
if (dc->frag_pool == NULL) {
SCLogError(SC_ERR_MEM_ALLOC,
"Defrag: Failed to initialize fragment pool.");
exit(EXIT_FAILURE);
}
if (SCMutexInit(&dc->frag_pool_lock, NULL) != 0) {
SCLogError(SC_ERR_MUTEX,
"Defrag: Failed to initialize frag pool mutex.");
exit(EXIT_FAILURE);
}
/* Set the default timeout. */
intmax_t timeout;
if (!ConfGetInt("defrag.timeout", &timeout)) {
dc->timeout = TIMEOUT_DEFAULT;
}
else {
if (timeout < TIMEOUT_MIN) {
SCLogError(SC_ERR_INVALID_ARGUMENT,
"defrag: Timeout less than minimum allowed value.");
exit(EXIT_FAILURE);
}
else if (timeout > TIMEOUT_MAX) {
SCLogError(SC_ERR_INVALID_ARGUMENT,
"defrag: Tiemout greater than maximum allowed value.");
exit(EXIT_FAILURE);
}
dc->timeout = timeout;
}
SCLogDebug("Defrag Initialized:");
SCLogDebug("\tTimeout: %"PRIuMAX, (uintmax_t)dc->timeout);
SCLogDebug("\tMaximum defrag trackers: %"PRIuMAX, tracker_pool_size);
SCLogDebug("\tPreallocated defrag trackers: %"PRIuMAX, tracker_pool_size);
SCLogDebug("\tMaximum fragments: %d", frag_pool_size);
SCLogDebug("\tPreallocated fragments: %d", frag_pool_prealloc);
return dc;
}
static void
DefragContextDestroy(DefragContext *dc)
{
if (dc == NULL)
return;
HashListTableFree(dc->frag_table);
PoolFree(dc->frag_pool);
PoolFree(dc->tracker_pool);
free(dc);
}
/**
* Attempt to re-assemble a packet.
*
* \param tracker The defragmentation tracker to reassemble from.
*/
static Packet *
Defrag4Reassemble(ThreadVars *tv, DefragContext *dc, DefragTracker *tracker,
Packet *p)
{
Packet *rp = NULL;
/* Should not be here unless we have seen the last fragment. */
if (!tracker->seen_last)
return NULL;
/* Check that we have all the data. Relies on the fact that
* fragments are inserted if frag_offset order. */
Frag *frag;
int len = 0;
TAILQ_FOREACH(frag, &tracker->frags, next) {
if (frag->skip)
continue;
if (frag == TAILQ_FIRST(&tracker->frags)) {
if (frag->offset != 0) {
goto done;
}
len = frag->data_len;
}
else {
if (frag->offset > len) {
/* This fragment starts after the end of the previous
* fragment. We have a hole. */
goto done;
}
else {
len += frag->data_len;
}
}
}
/* Allocate a Packet for the reassembled packet. On failure we
* free all the resources held by this tracker. */
if (tv == NULL) {
/* Unit test. */
rp = SetupPkt();
}
else {
/* Not really a tunnel packet, but more of a pseudo packet.
* But for the most part we should get the same result. */
rp = TunnelPktSetup(tv, NULL, p, (uint8_t *)p->ip4h, IPV4_GET_IPLEN(p),
IPV4_GET_IPPROTO(p));
}
if (rp == NULL) {
SCLogError(SC_ERR_MEM_ALLOC, "Failed to allocate packet for fragmentation re-assembly, dumping fragments.");
goto remove_tracker;
}
int fragmentable_offset = 0;
int fragmentable_len = 0;
int hlen = 0;
int ip_hdr_offset = 0;
TAILQ_FOREACH(frag, &tracker->frags, next) {
if (frag->skip)
continue;
if (frag->data_len - frag->ltrim <= 0)
continue;
if (frag->offset == 0) {
/* This is the first packet, we use this packets link and
* IPv4 header. We also copy in its data. */
memcpy(rp->pkt, frag->pkt, frag->len);
rp->ip4h = (IPV4Hdr *)(rp->pkt + frag->ip_hdr_offset);
hlen = frag->hlen;
ip_hdr_offset = frag->ip_hdr_offset;
/* This is the start of the fragmentable portion of the
* first packet. All fragment offsets are relative to
* this. */
fragmentable_offset = frag->ip_hdr_offset + frag->hlen;
fragmentable_len = frag->data_len;
}
else {
int pkt_end = fragmentable_offset + frag->offset + frag->data_len;
if (pkt_end > (int)sizeof(rp->pkt)) {
SCLogWarning(SC_ERR_REASSEMBLY, "Failed re-assemble fragmented packet, exceeds size of packet buffer.");
goto remove_tracker;
}
memcpy(rp->pkt + fragmentable_offset + frag->offset + frag->ltrim,
frag->pkt + frag->data_offset + frag->ltrim,
frag->data_len - frag->ltrim);
if (frag->offset + frag->data_len > fragmentable_len)
fragmentable_len = frag->offset + frag->data_len;
}
}
BUG_ON(rp->ip4h == NULL);
int old = rp->ip4h->ip_len + rp->ip4h->ip_off;
rp->ip4h->ip_len = htons(fragmentable_len + hlen);
rp->ip4h->ip_off = 0;
rp->ip4h->ip_csum = FixChecksum(rp->ip4h->ip_csum,
old, rp->ip4h->ip_len + rp->ip4h->ip_off);
rp->pktlen = ip_hdr_offset + hlen + fragmentable_len;
IPV4_CACHE_INIT(rp);
remove_tracker:
/* Remove the frag tracker. */
SCMutexLock(&dc->frag_table_lock);
HashListTableRemove(dc->frag_table, tracker, sizeof(tracker));
SCMutexUnlock(&dc->frag_table_lock);
DefragTrackerReset(tracker);
SCMutexLock(&dc->tracker_pool_lock);
PoolReturn(dc->tracker_pool, tracker);
SCMutexUnlock(&dc->tracker_pool_lock);
done:
return rp;
}
/**
* Attempt to re-assemble a packet.
*
* \param tracker The defragmentation tracker to reassemble from.
*/
static Packet *
Defrag6Reassemble(ThreadVars *tv, DefragContext *dc, DefragTracker *tracker,
Packet *p)
{
Packet *rp = NULL;
/* Should not be here unless we have seen the last fragment. */
if (!tracker->seen_last)
return NULL;
/* Check that we have all the data. Relies on the fact that
* fragments are inserted if frag_offset order. */
Frag *frag;
int len = 0;
TAILQ_FOREACH(frag, &tracker->frags, next) {
if (frag->skip)
continue;
if (frag == TAILQ_FIRST(&tracker->frags)) {
if (frag->offset != 0) {
goto done;
}
len = frag->data_len;
}
else {
if (frag->offset > len) {
/* This fragment starts after the end of the previous
* fragment. We have a hole. */
goto done;
}
else {
len += frag->data_len;
}
}
}
/* Allocate a Packet for the reassembled packet. On failure we
* free all the resources held by this tracker. */
if (tv == NULL) {
/* Unit test. */
rp = SetupPkt();
}
else {
/* Not really a tunnel packet, but more of a pseudo packet.
* But for the most part we should get the same result. */
rp = TunnelPktSetup(tv, NULL, p, (uint8_t *)p->ip6h,
IPV6_GET_PLEN(p) + sizeof(IPV6Hdr), 0);
}
if (rp == NULL) {
SCLogError(SC_ERR_MEM_ALLOC, "Failed to allocate packet for fragmentation re-assembly, dumping fragments.");
goto remove_tracker;
}
int fragmentable_offset = 0;
int fragmentable_len = 0;
int ip_hdr_offset = 0;
uint8_t next_hdr = 0;
TAILQ_FOREACH(frag, &tracker->frags, next) {
if (frag->skip)
continue;
if (frag->data_len - frag->ltrim <= 0)
continue;
if (frag->offset == 0) {
IPV6FragHdr *frag_hdr = (IPV6FragHdr *)(frag->pkt +
frag->frag_hdr_offset);
next_hdr = frag_hdr->ip6fh_nxt;
/* This is the first packet, we use this packets link and
* IPv6 headers. We also copy in its data, but remove the
* fragmentation header. */
memcpy(rp->pkt, frag->pkt, frag->frag_hdr_offset);
memcpy(rp->pkt + frag->frag_hdr_offset,
frag->pkt + frag->frag_hdr_offset + sizeof(IPV6FragHdr),
frag->data_len);
rp->ip6h = (IPV6Hdr *)(rp->pkt + frag->ip_hdr_offset);
ip_hdr_offset = frag->ip_hdr_offset;
/* This is the start of the fragmentable portion of the
* first packet. All fragment offsets are relative to
* this. */
fragmentable_offset = frag->frag_hdr_offset;
fragmentable_len = frag->data_len;
}
else {
memcpy(rp->pkt + fragmentable_offset + frag->offset + frag->ltrim,
frag->pkt + frag->data_offset + frag->ltrim,
frag->data_len - frag->ltrim);
if (frag->offset + frag->data_len > fragmentable_len)
fragmentable_len = frag->offset + frag->data_len;
}
}
BUG_ON(rp->ip6h == NULL);
rp->ip6h->s_ip6_plen = htons(fragmentable_len);
rp->ip6h->s_ip6_nxt = next_hdr;
rp->pktlen = ip_hdr_offset + sizeof(IPV6Hdr) + fragmentable_len;
IPV6_CACHE_INIT(rp);
remove_tracker:
/* Remove the frag tracker. */
SCMutexLock(&dc->frag_table_lock);
HashListTableRemove(dc->frag_table, tracker, sizeof(tracker));
SCMutexUnlock(&dc->frag_table_lock);
DefragTrackerReset(tracker);
SCMutexLock(&dc->tracker_pool_lock);
PoolReturn(dc->tracker_pool, tracker);
SCMutexUnlock(&dc->tracker_pool_lock);
done:
return rp;
}
/**
* Insert a new IPv4/IPv6 fragment into a tracker.
*
* \todo Allocate packet buffers from a pool.
*/
static Packet *
DefragInsertFrag(ThreadVars *tv, DefragContext *dc, DefragTracker *tracker,
Packet *p)
{
Packet *r = NULL;
int ltrim = 0;
uint8_t more_frags;
uint16_t frag_offset;
/* IPv4 header length - IPv4 only. */
uint16_t hlen = 0;
/* This is the offset of the start of the data in the packet that
* falls after the IP header. */
uint16_t data_offset;
/* The length of the (fragmented) data. This is the length of the
* data that falls after the IP header. */
uint16_t data_len;
/* Where the fragment ends. */
uint16_t frag_end;
/* Offset in the packet to the IPv6 header. */
uint16_t ip_hdr_offset;
/* Offset in the packet to the IPv6 frag header. IPv6 only. */
uint16_t frag_hdr_offset = 0;
if (tracker->af == AF_INET) {
more_frags = IPV4_GET_MF(p);
frag_offset = IPV4_GET_IPOFFSET(p) << 3;
hlen = IPV4_GET_HLEN(p);
data_offset = (uint8_t *)p->ip4h + hlen - p->pkt;
data_len = IPV4_GET_IPLEN(p) - hlen;
frag_end = frag_offset + data_len;
ip_hdr_offset = (uint8_t *)p->ip4h - p->pkt;
/* Ignore fragment if the end of packet extends past the
* maximum size of a packet. */
if (IPV4_HEADER_LEN + frag_offset + data_len > IPV4_MAXPACKET_LEN) {
/** \todo Perhaps log something? */
return NULL;;
}
}
else if (tracker->af == AF_INET6) {
more_frags = IPV6_EXTHDR_GET_FH_FLAG(p);
frag_offset = IPV6_EXTHDR_GET_FH_OFFSET(p);
data_offset = (uint8_t *)p->ip6eh.ip6fh + sizeof(IPV6FragHdr) - p->pkt;
data_len = IPV6_GET_PLEN(p) - (
((uint8_t *)p->ip6eh.ip6fh + sizeof(IPV6FragHdr)) -
((uint8_t *)p->ip6h + sizeof(IPV6Hdr)));
frag_end = frag_offset + data_len;
ip_hdr_offset = (uint8_t *)p->ip6h - p->pkt;
frag_hdr_offset = (uint8_t *)p->ip6eh.ip6fh - p->pkt;
/* Ignore fragment if the end of packet extends past the
* maximum size of a packet. */
if (frag_offset + data_len > IPV6_MAXPACKET) {
/** \todo Perhaps log something? */
return NULL;
}
}
else {
/* Abort - should not happen. */
SCLogWarning(SC_ERR_INVALID_ARGUMENT, "Invalid address family, aborting.");
return NULL;
}
/* Lock this tracker as we'll be doing list operations on it. */
SCMutexLock(&tracker->lock);
/* Update timeout. */
tracker->timeout = p->ts;
tracker->timeout.tv_sec += dc->timeout;
Frag *prev = NULL, *next;;
if (!TAILQ_EMPTY(&tracker->frags)) {
TAILQ_FOREACH(prev, &tracker->frags, next) {
ltrim = 0;
next = TAILQ_NEXT(prev, next);
switch (tracker->policy) {
case POLICY_BSD:
if (frag_offset < prev->offset + prev->data_len) {
if (frag_offset >= prev->offset) {
ltrim = prev->offset + prev->data_len - frag_offset;
}
if ((next != NULL) && (frag_end > next->offset)) {
next->ltrim = frag_end - next->offset;
}
if ((frag_offset < prev->offset) &&
(frag_end >= prev->offset + prev->data_len)) {
prev->skip = 1;
}
goto insert;
}
break;
case POLICY_LINUX:
if (frag_offset < prev->offset + prev->data_len) {
if (frag_offset > prev->offset) {
ltrim = prev->offset + prev->data_len - frag_offset;
}
if ((next != NULL) && (frag_end > next->offset)) {
next->ltrim = frag_end - next->offset;
}
if ((frag_offset < prev->offset) &&
(frag_end >= prev->offset + prev->data_len)) {
prev->skip = 1;
}
goto insert;
}
break;
case POLICY_WINDOWS:
if (frag_offset < prev->offset + prev->data_len) {
if (frag_offset >= prev->offset) {
ltrim = prev->offset + prev->data_len - frag_offset;
}
if ((frag_offset < prev->offset) &&
(frag_end > prev->offset + prev->data_len)) {
prev->skip = 1;
}
goto insert;
}
break;
case POLICY_SOLARIS:
if (frag_offset < prev->offset + prev->data_len) {
if (frag_offset >= prev->offset) {
ltrim = prev->offset + prev->data_len - frag_offset;
}
if ((frag_offset < prev->offset) &&
(frag_end >= prev->offset + prev->data_len)) {
prev->skip = 1;
}
goto insert;
}
break;
case POLICY_FIRST:
if ((frag_offset >= prev->offset) &&
(frag_end <= prev->offset + prev->data_len))
goto done;
if (frag_offset < prev->offset)
goto insert;
if (frag_offset < prev->offset + prev->data_len) {
ltrim = prev->offset + prev->data_len - frag_offset;
goto insert;
}
break;
case POLICY_LAST:
if (frag_offset <= prev->offset) {
if (frag_end > prev->offset)
prev->ltrim = frag_end - prev->offset;
goto insert;
}
break;
default:
break;
}
}
}
insert:
if (data_len - ltrim <= 0) {
goto done;
}
/* Allocate fragment and insert. */
SCMutexLock(&dc->frag_pool_lock);
Frag *new = PoolGet(dc->frag_pool);
SCMutexUnlock(&dc->frag_pool_lock);
if (new == NULL) {
goto done;
}
new->pkt = malloc(p->pktlen);
if (new->pkt == NULL) {
SCMutexLock(&dc->frag_pool_lock);
PoolReturn(dc->frag_pool, new);
SCMutexUnlock(&dc->frag_pool_lock);
goto done;
}
memcpy(new->pkt, p->pkt + ltrim, p->pktlen - ltrim);
new->len = p->pktlen - ltrim;
new->hlen = hlen;
new->offset = frag_offset + ltrim;
new->data_offset = data_offset;
new->data_len = data_len - ltrim;
new->ip_hdr_offset = ip_hdr_offset;
new->frag_hdr_offset = frag_hdr_offset;
Frag *frag;
TAILQ_FOREACH(frag, &tracker->frags, next) {
if (frag_offset < frag->offset)
break;
}
if (frag == NULL) {
TAILQ_INSERT_TAIL(&tracker->frags, new, next);
}
else {
TAILQ_INSERT_BEFORE(frag, new, next);
}
if (!more_frags) {
tracker->seen_last = 1;
}
if (tracker->seen_last) {
if (tracker->af == AF_INET)
r = Defrag4Reassemble(tv, dc, tracker, p);
else if (tracker->af == AF_INET6)
r = Defrag6Reassemble(tv, dc, tracker, p);
}
done:
SCMutexUnlock(&tracker->lock);
return r;
}
/**
* \brief Timeout a tracker.
*
* Called when we fail to get a tracker from the pool. The first
* tracker that has expired will be released back to the pool then the
* function will exit.
*
* Intended to be called with the tracker pool already locked.
*
* \param dc Current DefragContext.
* \param p Packet that triggered this timeout run, used for timestamp.
*/
static void
DefragTimeoutTracker(DefragContext *dc, Packet *p)
{
struct timeval tv = p->ts;
HashListTableBucket *next = HashListTableGetListHead(dc->frag_table);
DefragTracker *tracker;
while (next != NULL) {
tracker = HashListTableGetListData(next);
if (timercmp(&tracker->timeout, &tv, <)) {
/* Tracker has timeout out. */
HashListTableRemove(dc->frag_table, tracker, sizeof(tracker));
DefragTrackerReset(tracker);
PoolReturn(dc->tracker_pool, tracker);
return;
}
next = HashListTableGetListNext(next);
}
}
static DefragTracker *
DefragGetTracker(DefragContext *dc, DefragTracker *lookup_key, Packet *p)
{
DefragTracker *tracker;
SCMutexLock(&dc->frag_table_lock);
tracker = HashListTableLookup(dc->frag_table, lookup_key,
sizeof(*lookup_key));
if (tracker == NULL) {
SCMutexLock(&dc->tracker_pool_lock);
tracker = PoolGet(dc->tracker_pool);
if (tracker == NULL) {
/* Timeout trackers and try again. */
DefragTimeoutTracker(dc, p);
tracker = PoolGet(dc->tracker_pool);
}
SCMutexUnlock(&dc->tracker_pool_lock);
if (tracker == NULL) {
/* Report memory error - actually a pool allocation error. */
SCLogError(SC_ERR_MEM_ALLOC, "Defrag: Failed to allocate tracker.");
goto done;
}
DefragTrackerReset(tracker);
tracker->af = lookup_key->af;
tracker->id = lookup_key->id;
tracker->src_addr = lookup_key->src_addr;
tracker->dst_addr = lookup_key->dst_addr;
/* XXX Do policy lookup. */
tracker->policy = dc->default_policy;
if (HashListTableAdd(dc->frag_table, tracker, sizeof(*tracker)) != 0) {
/* Failed to add new tracker. */
SCLogError(SC_ERR_MEM_ALLOC,
"Defrag: Failed to add new tracker to hash table.");
SCMutexLock(&dc->tracker_pool_lock);
PoolReturn(dc->tracker_pool, tracker);
SCMutexUnlock(&dc->tracker_pool_lock);
goto done;
}
}
done:
SCMutexUnlock(&dc->frag_table_lock);
return tracker;
}
/**
* \brief Entry point for IPv4 and IPv6 fragments.
*
* \param tv ThreadVars for the calling decoder.
* \param dc A DefragContext to use, may be NULL for the default.
* \param p The packet fragment.
*
* \retval A new Packet resembling the re-assembled packet if the most
* recent fragment allowed the packet to be re-assembled, otherwise
* NULL is returned.
*/
Packet *
Defrag(ThreadVars *tv, DefragContext *dc, Packet *p)
{
uint16_t frag_offset;
uint8_t more_frags;
DefragTracker *tracker, lookup;
uint32_t id;
int af;
/* If no DefragContext was passed in, use the global one. Passing
* one in is primarily useful for unit tests. */
if (dc == NULL)
dc = defrag_context;
if (PKT_IS_IPV4(p)) {
af = AF_INET;
more_frags = IPV4_GET_MF(p);
frag_offset = IPV4_GET_IPOFFSET(p);
id = IPV4_GET_IPID(p);
}
else if (PKT_IS_IPV6(p)) {
af = AF_INET6;
frag_offset = IPV6_EXTHDR_GET_FH_OFFSET(p);
more_frags = IPV6_EXTHDR_GET_FH_FLAG(p);
id = IPV6_EXTHDR_GET_FH_ID(p);
}
else {
return NULL;
}
if (frag_offset == 0 && more_frags == 0) {
return NULL;
}
/* Create a lookup key. */
lookup.af = af;
lookup.id = id;
lookup.src_addr = p->src;
lookup.dst_addr = p->dst;
tracker = DefragGetTracker(dc, &lookup, p);
if (tracker == NULL)
return NULL;
return DefragInsertFrag(tv, dc, tracker, p);
}
void
DefragInit(void)
{
/* Initialize random value for hashing and hash table size. */
unsigned int seed = RandomTimePreseed();
/* set defaults */
defrag_hash_rand = (int)( DEFAULT_DEFRAG_HASH_SIZE * (rand_r(&seed) / RAND_MAX + 1.0));
defrag_hash_size = DEFAULT_DEFRAG_HASH_SIZE;
/* Allocate the DefragContext. */
defrag_context = DefragContextNew();
if (defrag_context == NULL) {
SCLogError(SC_ERR_MEM_ALLOC,
"Failed to allocate memory for the Defrag module.");
exit(EXIT_FAILURE);
}
}
void DefragDestroy(void) {
DefragContextDestroy(defrag_context);
defrag_context = NULL;
}
#ifdef UNITTESTS
#define IP_MF 0x2000
/**
* Allocate a test packet. Nothing to fancy, just a simple IP packet
* with some payload of no particular protocol.
*/
static Packet *
BuildTestPacket(uint16_t id, uint16_t off, int mf, const char content,
int content_len)
{
Packet *p = NULL;
int hlen = 20;
int ttl = 64;
p = calloc(1, sizeof(*p));
if (p == NULL)
return NULL;
gettimeofday(&p->ts, NULL);
p->ip4h = (IPV4Hdr *)p->pkt;
p->ip4h->ip_verhl = 4 << 4;
p->ip4h->ip_verhl |= hlen >> 2;
p->ip4h->ip_len = htons(hlen + content_len);
p->ip4h->ip_id = htons(id);
p->ip4h->ip_off = htons(off);
if (mf)
p->ip4h->ip_off = htons(IP_MF | off);
else
p->ip4h->ip_off = htons(off);
p->ip4h->ip_ttl = ttl;
p->ip4h->ip_proto = IPPROTO_ICMP;
p->ip4h->ip_src.s_addr = 0x01010101; /* 1.1.1.1 */
p->ip4h->ip_dst.s_addr = 0x02020202; /* 2.2.2.2 */
SET_IPV4_SRC_ADDR(p, &p->src);
SET_IPV4_DST_ADDR(p, &p->dst);
memset(p->pkt + hlen, content, content_len);
p->pktlen = hlen + content_len;
p->ip4h->ip_csum = IPV4CalculateChecksum((uint16_t *)p->pkt, hlen);
/* Self test. */
IPV4_CACHE_INIT(p);
if (IPV4_GET_VER(p) != 4)
goto error;
if (IPV4_GET_HLEN(p) != hlen)
goto error;
if (IPV4_GET_IPLEN(p) != hlen + content_len)
goto error;
if (IPV4_GET_IPID(p) != id)
goto error;
if (IPV4_GET_IPOFFSET(p) != off)
goto error;
if (IPV4_GET_MF(p) != mf)
goto error;
if (IPV4_GET_IPTTL(p) != ttl)
goto error;
if (IPV4_GET_IPPROTO(p) != IPPROTO_ICMP)
goto error;
return p;
error:
if (p != NULL)
free(p);
return NULL;
}
static Packet *
IPV6BuildTestPacket(uint32_t id, uint16_t off, int mf, const char content,
int content_len)
{
Packet *p = NULL;
p = calloc(1, sizeof(*p));
if (p == NULL)
return NULL;
gettimeofday(&p->ts, NULL);
p->ip6h = (IPV6Hdr *)p->pkt;
IPV6_SET_RAW_VER(p->ip6h, 6);
p->ip6h->s_ip6_nxt = 44;
p->ip6h->s_ip6_hlim = 2;
/* Source and dest address - very bogus addresses. */
p->ip6h->ip6_src[0] = 0x01010101;
p->ip6h->ip6_src[1] = 0x01010101;
p->ip6h->ip6_src[2] = 0x01010101;
p->ip6h->ip6_src[3] = 0x01010101;
p->ip6h->ip6_dst[0] = 0x02020202;
p->ip6h->ip6_dst[1] = 0x02020202;
p->ip6h->ip6_dst[2] = 0x02020202;
p->ip6h->ip6_dst[3] = 0x02020202;
/* Fragmentation header. */
p->ip6eh.ip6fh = (IPV6FragHdr *)(p->pkt + sizeof(IPV6Hdr));
p->ip6eh.ip6fh->ip6fh_nxt = IPPROTO_ICMP;
p->ip6eh.ip6fh->ip6fh_ident = htonl(id);
p->ip6eh.ip6fh->ip6fh_offlg = htons((off << 3) | mf);
memset(p->pkt + sizeof(IPV6Hdr) + sizeof(IPV6FragHdr), content,
content_len);
p->pktlen = sizeof(IPV6Hdr) + sizeof(IPV6FragHdr) + content_len;
p->ip6h->s_ip6_plen = htons(sizeof(IPV6FragHdr) + content_len);
SET_IPV6_SRC_ADDR(p, &p->src);
SET_IPV6_DST_ADDR(p, &p->dst);
/* Self test. */
IPV6_CACHE_INIT(p);
if (IPV6_GET_VER(p) != 6)
goto error;
if (IPV6_GET_NH(p) != 44)
goto error;
if (IPV6_GET_PLEN(p) != sizeof(IPV6FragHdr) + content_len)
goto error;
return p;
error:
fprintf(stderr, "Error building test packet.\n");
if (p != NULL)
free(p);
return NULL;
}
/**
* Test the simplest possible re-assembly scenario. All packet in
* order and no overlaps.
*/
static int
DefragInOrderSimpleTest(void)
{
DefragContext *dc = NULL;
Packet *p1 = NULL, *p2 = NULL, *p3 = NULL;
Packet *reassembled = NULL;
int id = 12;
int i;
int ret = 0;
DefragInit();
dc = DefragContextNew();
if (dc == NULL)
goto end;
p1 = BuildTestPacket(id, 0, 1, 'A', 8);
if (p1 == NULL)
goto end;
p2 = BuildTestPacket(id, 1, 1, 'B', 8);
if (p2 == NULL)
goto end;
p3 = BuildTestPacket(id, 2, 0, 'C', 3);
if (p3 == NULL)
goto end;
if (Defrag(NULL, dc, p1) != NULL)
goto end;
if (Defrag(NULL, dc, p2) != NULL)
goto end;
reassembled = Defrag(NULL, dc, p3);
if (reassembled == NULL)
goto end;
if (IPV4_GET_HLEN(reassembled) != 20)
goto end;
if (IPV4_GET_IPLEN(reassembled) != 39)
goto end;
/* 20 bytes in we should find 8 bytes of A. */
for (i = 20; i < 20 + 8; i++) {
if (reassembled->pkt[i] != 'A')
goto end;
}
/* 28 bytes in we should find 8 bytes of B. */
for (i = 28; i < 28 + 8; i++) {
if (reassembled->pkt[i] != 'B')
goto end;
}
/* And 36 bytes in we should find 3 bytes of C. */
for (i = 36; i < 36 + 3; i++) {
if (reassembled->pkt[i] != 'C')
goto end;
}
ret = 1;
end:
if (dc != NULL)
DefragContextDestroy(dc);
if (p1 != NULL)
free(p1);
if (p2 != NULL)
free(p2);
if (p3 != NULL)
free(p3);
if (reassembled != NULL)
free(reassembled);
DefragDestroy();
return ret;
}
/**
* Simple fragmented packet in reverse order.
*/
static int
DefragReverseSimpleTest(void)
{
DefragContext *dc = NULL;
Packet *p1 = NULL, *p2 = NULL, *p3 = NULL;
Packet *reassembled = NULL;
int id = 12;
int i;
int ret = 0;
DefragInit();
dc = DefragContextNew();
if (dc == NULL)
goto end;
p1 = BuildTestPacket(id, 0, 1, 'A', 8);
if (p1 == NULL)
goto end;
p2 = BuildTestPacket(id, 1, 1, 'B', 8);
if (p2 == NULL)
goto end;
p3 = BuildTestPacket(id, 2, 0, 'C', 3);
if (p3 == NULL)
goto end;
if (Defrag(NULL, dc, p3) != NULL)
goto end;
if (Defrag(NULL, dc, p2) != NULL)
goto end;
reassembled = Defrag(NULL, dc, p1);
if (reassembled == NULL)
goto end;
if (IPV4_GET_HLEN(reassembled) != 20)
goto end;
if (IPV4_GET_IPLEN(reassembled) != 39)
goto end;
/* 20 bytes in we should find 8 bytes of A. */
for (i = 20; i < 20 + 8; i++) {
if (reassembled->pkt[i] != 'A')
goto end;
}
/* 28 bytes in we should find 8 bytes of B. */
for (i = 28; i < 28 + 8; i++) {
if (reassembled->pkt[i] != 'B')
goto end;
}
/* And 36 bytes in we should find 3 bytes of C. */
for (i = 36; i < 36 + 3; i++) {
if (reassembled->pkt[i] != 'C')
goto end;
}
ret = 1;
end:
if (dc != NULL)
DefragContextDestroy(dc);
if (p1 != NULL)
free(p1);
if (p2 != NULL)
free(p2);
if (p3 != NULL)
free(p3);
if (reassembled != NULL)
free(reassembled);
DefragDestroy();
return ret;
}
/**
* Test the simplest possible re-assembly scenario. All packet in
* order and no overlaps.
*/
static int
IPV6DefragInOrderSimpleTest(void)
{
DefragContext *dc = NULL;
Packet *p1 = NULL, *p2 = NULL, *p3 = NULL;
Packet *reassembled = NULL;
int id = 12;
int i;
int ret = 0;
DefragInit();
dc = DefragContextNew();
if (dc == NULL)
goto end;
p1 = IPV6BuildTestPacket(id, 0, 1, 'A', 8);
if (p1 == NULL)
goto end;
p2 = IPV6BuildTestPacket(id, 1, 1, 'B', 8);
if (p2 == NULL)
goto end;
p3 = IPV6BuildTestPacket(id, 2, 0, 'C', 3);
if (p3 == NULL)
goto end;
if (Defrag(NULL, dc, p1) != NULL)
goto end;
if (Defrag(NULL, dc, p2) != NULL)
goto end;
reassembled = Defrag(NULL, dc, p3);
if (reassembled == NULL)
goto end;
if (IPV6_GET_PLEN(reassembled) != 19)
goto end;
/* 40 bytes in we should find 8 bytes of A. */
for (i = 40; i < 40 + 8; i++) {
if (reassembled->pkt[i] != 'A')
goto end;
}
/* 28 bytes in we should find 8 bytes of B. */
for (i = 48; i < 48 + 8; i++) {
if (reassembled->pkt[i] != 'B')
goto end;
}
/* And 36 bytes in we should find 3 bytes of C. */
for (i = 56; i < 56 + 3; i++) {
if (reassembled->pkt[i] != 'C')
goto end;
}
ret = 1;
end:
if (dc != NULL)
DefragContextDestroy(dc);
if (p1 != NULL)
free(p1);
if (p2 != NULL)
free(p2);
if (p3 != NULL)
free(p3);
if (reassembled != NULL)
free(reassembled);
DefragDestroy();
return ret;
}
static int
IPV6DefragReverseSimpleTest(void)
{
DefragContext *dc = NULL;
Packet *p1 = NULL, *p2 = NULL, *p3 = NULL;
Packet *reassembled = NULL;
int id = 12;
int i;
int ret = 0;
DefragInit();
dc = DefragContextNew();
if (dc == NULL)
goto end;
p1 = IPV6BuildTestPacket(id, 0, 1, 'A', 8);
if (p1 == NULL)
goto end;
p2 = IPV6BuildTestPacket(id, 1, 1, 'B', 8);
if (p2 == NULL)
goto end;
p3 = IPV6BuildTestPacket(id, 2, 0, 'C', 3);
if (p3 == NULL)
goto end;
if (Defrag(NULL, dc, p3) != NULL)
goto end;
if (Defrag(NULL, dc, p2) != NULL)
goto end;
reassembled = Defrag(NULL, dc, p1);
if (reassembled == NULL)
goto end;
/* 40 bytes in we should find 8 bytes of A. */
for (i = 40; i < 40 + 8; i++) {
if (reassembled->pkt[i] != 'A')
goto end;
}
/* 28 bytes in we should find 8 bytes of B. */
for (i = 48; i < 48 + 8; i++) {
if (reassembled->pkt[i] != 'B')
goto end;
}
/* And 36 bytes in we should find 3 bytes of C. */
for (i = 56; i < 56 + 3; i++) {
if (reassembled->pkt[i] != 'C')
goto end;
}
ret = 1;
end:
if (dc != NULL)
DefragContextDestroy(dc);
if (p1 != NULL)
free(p1);
if (p2 != NULL)
free(p2);
if (p3 != NULL)
free(p3);
if (reassembled != NULL)
free(reassembled);
DefragDestroy();
return ret;
}
static int
DefragDoSturgesNovakTest(int policy, u_char *expected, size_t expected_len)
{
int i;
int ret = 0;
DefragContext *dc = NULL;
DefragInit();
/*
* Build the packets.
*/
int id = 1;
Packet *packets[17];
memset(packets, 0x00, sizeof(packets));
/*
* Original fragments.
*/
/* A*24 at 0. */
packets[0] = BuildTestPacket(id, 0, 1, 'A', 24);
/* B*15 at 32. */
packets[1] = BuildTestPacket(id, 32 >> 3, 1, 'B', 16);
/* C*24 at 48. */
packets[2] = BuildTestPacket(id, 48 >> 3, 1, 'C', 24);
/* D*8 at 80. */
packets[3] = BuildTestPacket(id, 80 >> 3, 1, 'D', 8);
/* E*16 at 104. */
packets[4] = BuildTestPacket(id, 104 >> 3, 1, 'E', 16);
/* F*24 at 120. */
packets[5] = BuildTestPacket(id, 120 >> 3, 1, 'F', 24);
/* G*16 at 144. */
packets[6] = BuildTestPacket(id, 144 >> 3, 1, 'G', 16);
/* H*16 at 160. */
packets[7] = BuildTestPacket(id, 160 >> 3, 1, 'H', 16);
/* I*8 at 176. */
packets[8] = BuildTestPacket(id, 176 >> 3, 1, 'I', 8);
/*
* Overlapping subsequent fragments.
*/
/* J*32 at 8. */
packets[9] = BuildTestPacket(id, 8 >> 3, 1, 'J', 32);
/* K*24 at 48. */
packets[10] = BuildTestPacket(id, 48 >> 3, 1, 'K', 24);
/* L*24 at 72. */
packets[11] = BuildTestPacket(id, 72 >> 3, 1, 'L', 24);
/* M*24 at 96. */
packets[12] = BuildTestPacket(id, 96 >> 3, 1, 'M', 24);
/* N*8 at 128. */
packets[13] = BuildTestPacket(id, 128 >> 3, 1, 'N', 8);
/* O*8 at 152. */
packets[14] = BuildTestPacket(id, 152 >> 3, 1, 'O', 8);
/* P*8 at 160. */
packets[15] = BuildTestPacket(id, 160 >> 3, 1, 'P', 8);
/* Q*16 at 176. */
packets[16] = BuildTestPacket(id, 176 >> 3, 0, 'Q', 16);
dc = DefragContextNew();
if (dc == NULL)
goto end;
dc->default_policy = policy;
/* Send all but the last. */
for (i = 0; i < 16; i++) {
Packet *tp = Defrag(NULL, dc, packets[i]);
if (tp != NULL) {
free(tp);
goto end;
}
}
/* And now the last one. */
Packet *reassembled = Defrag(NULL, dc, packets[16]);
if (reassembled == NULL)
goto end;
if (IPV4_GET_HLEN(reassembled) != 20)
goto end;
if (IPV4_GET_IPLEN(reassembled) != 20 + 192)
goto end;
if (memcmp(reassembled->pkt + 20, expected, expected_len) != 0)
goto end;
free(reassembled);
/* Make sure the tracker was released back to the pool. */
if (dc->tracker_pool->outstanding != 0)
return 0;
/* Make sure all frags were returned back to the pool. */
if (dc->frag_pool->outstanding != 0)
return 0;
ret = 1;
end:
if (dc != NULL)
DefragContextDestroy(dc);
for (i = 0; i < 17; i++) {
free(packets[i]);
}
DefragDestroy();
return ret;
}
static int
IPV6DefragDoSturgesNovakTest(int policy, u_char *expected, size_t expected_len)
{
int i;
int ret = 0;
DefragContext *dc = NULL;
DefragInit();
/*
* Build the packets.
*/
int id = 1;
Packet *packets[17];
memset(packets, 0x00, sizeof(packets));
/*
* Original fragments.
*/
/* A*24 at 0. */
packets[0] = IPV6BuildTestPacket(id, 0, 1, 'A', 24);
/* B*15 at 32. */
packets[1] = IPV6BuildTestPacket(id, 32 >> 3, 1, 'B', 16);
/* C*24 at 48. */
packets[2] = IPV6BuildTestPacket(id, 48 >> 3, 1, 'C', 24);
/* D*8 at 80. */
packets[3] = IPV6BuildTestPacket(id, 80 >> 3, 1, 'D', 8);
/* E*16 at 104. */
packets[4] = IPV6BuildTestPacket(id, 104 >> 3, 1, 'E', 16);
/* F*24 at 120. */
packets[5] = IPV6BuildTestPacket(id, 120 >> 3, 1, 'F', 24);
/* G*16 at 144. */
packets[6] = IPV6BuildTestPacket(id, 144 >> 3, 1, 'G', 16);
/* H*16 at 160. */
packets[7] = IPV6BuildTestPacket(id, 160 >> 3, 1, 'H', 16);
/* I*8 at 176. */
packets[8] = IPV6BuildTestPacket(id, 176 >> 3, 1, 'I', 8);
/*
* Overlapping subsequent fragments.
*/
/* J*32 at 8. */
packets[9] = IPV6BuildTestPacket(id, 8 >> 3, 1, 'J', 32);
/* K*24 at 48. */
packets[10] = IPV6BuildTestPacket(id, 48 >> 3, 1, 'K', 24);
/* L*24 at 72. */
packets[11] = IPV6BuildTestPacket(id, 72 >> 3, 1, 'L', 24);
/* M*24 at 96. */
packets[12] = IPV6BuildTestPacket(id, 96 >> 3, 1, 'M', 24);
/* N*8 at 128. */
packets[13] = IPV6BuildTestPacket(id, 128 >> 3, 1, 'N', 8);
/* O*8 at 152. */
packets[14] = IPV6BuildTestPacket(id, 152 >> 3, 1, 'O', 8);
/* P*8 at 160. */
packets[15] = IPV6BuildTestPacket(id, 160 >> 3, 1, 'P', 8);
/* Q*16 at 176. */
packets[16] = IPV6BuildTestPacket(id, 176 >> 3, 0, 'Q', 16);
dc = DefragContextNew();
if (dc == NULL)
goto end;
dc->default_policy = policy;
/* Send all but the last. */
Packet *tp;
tp = Defrag(NULL, dc, packets[0]);
if (tp != NULL) {
free(tp);
goto end;
}
tp = Defrag(NULL, dc, packets[1]);
if (tp != NULL) {
free(tp);
goto end;
}
tp = Defrag(NULL, dc, packets[2]);
if (tp != NULL) {
free(tp);
goto end;
}
tp = Defrag(NULL, dc, packets[3]);
if (tp != NULL) {
free(tp);
goto end;
}
tp = Defrag(NULL, dc, packets[4]);
if (tp != NULL) {
free(tp);
goto end;
}
tp = Defrag(NULL, dc, packets[5]);
if (tp != NULL) {
free(tp);
goto end;
}
tp = Defrag(NULL, dc, packets[6]);
if (tp != NULL) {
free(tp);
goto end;
}
tp = Defrag(NULL, dc, packets[7]);
if (tp != NULL) {
free(tp);
goto end;
}
tp = Defrag(NULL, dc, packets[8]);
if (tp != NULL) {
free(tp);
goto end;
}
tp = Defrag(NULL, dc, packets[9]);
if (tp != NULL) {
free(tp);
goto end;
}
tp = Defrag(NULL, dc, packets[10]);
if (tp != NULL) {
free(tp);
goto end;
}
tp = Defrag(NULL, dc, packets[11]);
if (tp != NULL) {
free(tp);
goto end;
}
tp = Defrag(NULL, dc, packets[12]);
if (tp != NULL) {
free(tp);
goto end;
}
tp = Defrag(NULL, dc, packets[13]);
if (tp != NULL) {
free(tp);
goto end;
}
tp = Defrag(NULL, dc, packets[14]);
if (tp != NULL) {
free(tp);
goto end;
}
tp = Defrag(NULL, dc, packets[15]);
if (tp != NULL) {
free(tp);
goto end;
}
/* And now the last one. */
Packet *reassembled = Defrag(NULL, dc, packets[16]);
if (reassembled == NULL)
goto end;
if (memcmp(reassembled->pkt + 40, expected, expected_len) != 0)
goto end;
if (IPV6_GET_PLEN(reassembled) != 192)
goto end;
free(reassembled);
/* Make sure the tracker was released back to the pool. */
if (dc->tracker_pool->outstanding != 0)
return 0;
/* Make sure all frags were returned to the pool. */
if (dc->frag_pool->outstanding != 0)
return 0;
ret = 1;
end:
if (dc != NULL)
DefragContextDestroy(dc);
for (i = 0; i < 17; i++) {
free(packets[i]);
}
DefragDestroy();
return ret;
}
static int
DefragSturgesNovakBsdTest(void)
{
/* Expected data. */
u_char expected[] = {
"AAAAAAAA"
"AAAAAAAA"
"AAAAAAAA"
"JJJJJJJJ"
"JJJJJJJJ"
"BBBBBBBB"
"CCCCCCCC"
"CCCCCCCC"
"CCCCCCCC"
"LLLLLLLL"
"LLLLLLLL"
"LLLLLLLL"
"MMMMMMMM"
"MMMMMMMM"
"MMMMMMMM"
"FFFFFFFF"
"FFFFFFFF"
"FFFFFFFF"
"GGGGGGGG"
"GGGGGGGG"
"HHHHHHHH"
"HHHHHHHH"
"IIIIIIII"
"QQQQQQQQ"
};
return DefragDoSturgesNovakTest(POLICY_BSD, expected, sizeof(expected));
}
static int
IPV6DefragSturgesNovakBsdTest(void)
{
/* Expected data. */
u_char expected[] = {
"AAAAAAAA"
"AAAAAAAA"
"AAAAAAAA"
"JJJJJJJJ"
"JJJJJJJJ"
"BBBBBBBB"
"CCCCCCCC"
"CCCCCCCC"
"CCCCCCCC"
"LLLLLLLL"
"LLLLLLLL"
"LLLLLLLL"
"MMMMMMMM"
"MMMMMMMM"
"MMMMMMMM"
"FFFFFFFF"
"FFFFFFFF"
"FFFFFFFF"
"GGGGGGGG"
"GGGGGGGG"
"HHHHHHHH"
"HHHHHHHH"
"IIIIIIII"
"QQQQQQQQ"
};
return IPV6DefragDoSturgesNovakTest(POLICY_BSD, expected, sizeof(expected));
}
static int
DefragSturgesNovakLinuxTest(void)
{
/* Expected data. */
u_char expected[] = {
"AAAAAAAA"
"AAAAAAAA"
"AAAAAAAA"
"JJJJJJJJ"
"JJJJJJJJ"
"BBBBBBBB"
"KKKKKKKK"
"KKKKKKKK"
"KKKKKKKK"
"LLLLLLLL"
"LLLLLLLL"
"LLLLLLLL"
"MMMMMMMM"
"MMMMMMMM"
"MMMMMMMM"
"FFFFFFFF"
"FFFFFFFF"
"FFFFFFFF"
"GGGGGGGG"
"GGGGGGGG"
"PPPPPPPP"
"HHHHHHHH"
"QQQQQQQQ"
"QQQQQQQQ"
};
return DefragDoSturgesNovakTest(POLICY_LINUX, expected, sizeof(expected));
}
static int
IPV6DefragSturgesNovakLinuxTest(void)
{
/* Expected data. */
u_char expected[] = {
"AAAAAAAA"
"AAAAAAAA"
"AAAAAAAA"
"JJJJJJJJ"
"JJJJJJJJ"
"BBBBBBBB"
"KKKKKKKK"
"KKKKKKKK"
"KKKKKKKK"
"LLLLLLLL"
"LLLLLLLL"
"LLLLLLLL"
"MMMMMMMM"
"MMMMMMMM"
"MMMMMMMM"
"FFFFFFFF"
"FFFFFFFF"
"FFFFFFFF"
"GGGGGGGG"
"GGGGGGGG"
"PPPPPPPP"
"HHHHHHHH"
"QQQQQQQQ"
"QQQQQQQQ"
};
return IPV6DefragDoSturgesNovakTest(POLICY_LINUX, expected,
sizeof(expected));
}
static int
DefragSturgesNovakWindowsTest(void)
{
/* Expected data. */
u_char expected[] = {
"AAAAAAAA"
"AAAAAAAA"
"AAAAAAAA"
"JJJJJJJJ"
"BBBBBBBB"
"BBBBBBBB"
"CCCCCCCC"
"CCCCCCCC"
"CCCCCCCC"
"LLLLLLLL"
"LLLLLLLL"
"LLLLLLLL"
"MMMMMMMM"
"EEEEEEEE"
"EEEEEEEE"
"FFFFFFFF"
"FFFFFFFF"
"FFFFFFFF"
"GGGGGGGG"
"GGGGGGGG"
"HHHHHHHH"
"HHHHHHHH"
"IIIIIIII"
"QQQQQQQQ"
};
return DefragDoSturgesNovakTest(POLICY_WINDOWS, expected, sizeof(expected));
}
static int
IPV6DefragSturgesNovakWindowsTest(void)
{
/* Expected data. */
u_char expected[] = {
"AAAAAAAA"
"AAAAAAAA"
"AAAAAAAA"
"JJJJJJJJ"
"BBBBBBBB"
"BBBBBBBB"
"CCCCCCCC"
"CCCCCCCC"
"CCCCCCCC"
"LLLLLLLL"
"LLLLLLLL"
"LLLLLLLL"
"MMMMMMMM"
"EEEEEEEE"
"EEEEEEEE"
"FFFFFFFF"
"FFFFFFFF"
"FFFFFFFF"
"GGGGGGGG"
"GGGGGGGG"
"HHHHHHHH"
"HHHHHHHH"
"IIIIIIII"
"QQQQQQQQ"
};
return IPV6DefragDoSturgesNovakTest(POLICY_WINDOWS, expected,
sizeof(expected));
}
static int
DefragSturgesNovakSolarisTest(void)
{
/* Expected data. */
u_char expected[] = {
"AAAAAAAA"
"AAAAAAAA"
"AAAAAAAA"
"JJJJJJJJ"
"BBBBBBBB"
"BBBBBBBB"
"CCCCCCCC"
"CCCCCCCC"
"CCCCCCCC"
"LLLLLLLL"
"LLLLLLLL"
"LLLLLLLL"
"MMMMMMMM"
"MMMMMMMM"
"MMMMMMMM"
"FFFFFFFF"
"FFFFFFFF"
"FFFFFFFF"
"GGGGGGGG"
"GGGGGGGG"
"HHHHHHHH"
"HHHHHHHH"
"IIIIIIII"
"QQQQQQQQ"
};
return DefragDoSturgesNovakTest(POLICY_SOLARIS, expected, sizeof(expected));
}
static int
IPV6DefragSturgesNovakSolarisTest(void)
{
/* Expected data. */
u_char expected[] = {
"AAAAAAAA"
"AAAAAAAA"
"AAAAAAAA"
"JJJJJJJJ"
"BBBBBBBB"
"BBBBBBBB"
"CCCCCCCC"
"CCCCCCCC"
"CCCCCCCC"
"LLLLLLLL"
"LLLLLLLL"
"LLLLLLLL"
"MMMMMMMM"
"MMMMMMMM"
"MMMMMMMM"
"FFFFFFFF"
"FFFFFFFF"
"FFFFFFFF"
"GGGGGGGG"
"GGGGGGGG"
"HHHHHHHH"
"HHHHHHHH"
"IIIIIIII"
"QQQQQQQQ"
};
return IPV6DefragDoSturgesNovakTest(POLICY_SOLARIS, expected,
sizeof(expected));
}
static int
DefragSturgesNovakFirstTest(void)
{
/* Expected data. */
u_char expected[] = {
"AAAAAAAA"
"AAAAAAAA"
"AAAAAAAA"
"JJJJJJJJ"
"BBBBBBBB"
"BBBBBBBB"
"CCCCCCCC"
"CCCCCCCC"
"CCCCCCCC"
"LLLLLLLL"
"DDDDDDDD"
"LLLLLLLL"
"MMMMMMMM"
"EEEEEEEE"
"EEEEEEEE"
"FFFFFFFF"
"FFFFFFFF"
"FFFFFFFF"
"GGGGGGGG"
"GGGGGGGG"
"HHHHHHHH"
"HHHHHHHH"
"IIIIIIII"
"QQQQQQQQ"
};
return DefragDoSturgesNovakTest(POLICY_FIRST, expected, sizeof(expected));
}
static int
IPV6DefragSturgesNovakFirstTest(void)
{
/* Expected data. */
u_char expected[] = {
"AAAAAAAA"
"AAAAAAAA"
"AAAAAAAA"
"JJJJJJJJ"
"BBBBBBBB"
"BBBBBBBB"
"CCCCCCCC"
"CCCCCCCC"
"CCCCCCCC"
"LLLLLLLL"
"DDDDDDDD"
"LLLLLLLL"
"MMMMMMMM"
"EEEEEEEE"
"EEEEEEEE"
"FFFFFFFF"
"FFFFFFFF"
"FFFFFFFF"
"GGGGGGGG"
"GGGGGGGG"
"HHHHHHHH"
"HHHHHHHH"
"IIIIIIII"
"QQQQQQQQ"
};
return IPV6DefragDoSturgesNovakTest(POLICY_FIRST, expected,
sizeof(expected));
}
static int
DefragSturgesNovakLastTest(void)
{
/* Expected data. */
u_char expected[] = {
"AAAAAAAA"
"JJJJJJJJ"
"JJJJJJJJ"
"JJJJJJJJ"
"JJJJJJJJ"
"BBBBBBBB"
"KKKKKKKK"
"KKKKKKKK"
"KKKKKKKK"
"LLLLLLLL"
"LLLLLLLL"
"LLLLLLLL"
"MMMMMMMM"
"MMMMMMMM"
"MMMMMMMM"
"FFFFFFFF"
"NNNNNNNN"
"FFFFFFFF"
"GGGGGGGG"
"OOOOOOOO"
"PPPPPPPP"
"HHHHHHHH"
"QQQQQQQQ"
"QQQQQQQQ"
};
return DefragDoSturgesNovakTest(POLICY_LAST, expected, sizeof(expected));
}
static int
IPV6DefragSturgesNovakLastTest(void)
{
/* Expected data. */
u_char expected[] = {
"AAAAAAAA"
"JJJJJJJJ"
"JJJJJJJJ"
"JJJJJJJJ"
"JJJJJJJJ"
"BBBBBBBB"
"KKKKKKKK"
"KKKKKKKK"
"KKKKKKKK"
"LLLLLLLL"
"LLLLLLLL"
"LLLLLLLL"
"MMMMMMMM"
"MMMMMMMM"
"MMMMMMMM"
"FFFFFFFF"
"NNNNNNNN"
"FFFFFFFF"
"GGGGGGGG"
"OOOOOOOO"
"PPPPPPPP"
"HHHHHHHH"
"QQQQQQQQ"
"QQQQQQQQ"
};
return IPV6DefragDoSturgesNovakTest(POLICY_LAST, expected,
sizeof(expected));
}
static int
DefragTimeoutTest(void)
{
int i;
int ret = 0;
DefragContext *dc = NULL;
DefragInit();
/* Setup a small numberr of trackers. */
ConfSet("defrag.trackers", "16", 1);
dc = DefragContextNew();
if (dc == NULL)
goto end;
/* Load in 16 packets. */
for (i = 0; i < 16; i++) {
Packet *p = BuildTestPacket(i, 0, 1, 'A' + i, 16);
if (p == NULL)
goto end;
Packet *tp = Defrag(NULL, dc, p);
free(p);
if (tp != NULL) {
free(tp);
goto end;
}
}
/* Build a new packet but push the timestamp out by our timeout.
* This should force our previous fragments to be timed out. */
Packet *p = BuildTestPacket(99, 0, 1, 'A' + i, 16);
if (p == NULL)
goto end;
p->ts.tv_sec += dc->timeout;
Packet *tp = Defrag(NULL, dc, p);
free(p);
if (tp != NULL) {
free(tp);
goto end;
}
/* Iterate our HashList and look for the trackerr with id 99. */
int found = 0;
HashListTableBucket *next = HashListTableGetListHead(dc->frag_table);
if (next == NULL)
goto end;
for (;;) {
if (next == NULL)
break;
DefragTracker *tracker = HashListTableGetListData(next);
if (tracker->id == 99) {
found = 1;
break;
}
next = HashListTableGetListNext(next);
}
if (found == 0)
goto end;
ret = 1;
end:
if (dc != NULL)
DefragContextDestroy(dc);
DefragDestroy();
return ret;
}
/**
* QA found that if you send a packet where more frags is 0, offset is
* > 0 and there is no data in the packet that the re-assembler will
* fail. The fix was simple, but this unit test is just to make sure
* its not introduced.
*/
static int
DefragIPv4NoDataTest(void)
{
DefragContext *dc = NULL;
Packet *p = NULL;
int id = 12;
int ret = 0;
DefragInit();
dc = DefragContextNew();
if (dc == NULL)
goto end;
/* This packet has an offset > 0, more frags set to 0 and no data. */
p = BuildTestPacket(id, 1, 0, 'A', 0);
if (p == NULL)
goto end;
/* We do not expect a packet returned. */
if (Defrag(NULL, dc, p) != NULL)
goto end;
/* The fragment should have been ignored so no fragments should
* have been allocated from the pool. */
if (dc->frag_pool->outstanding != 0)
return 0;
ret = 1;
end:
if (dc != NULL)
DefragContextDestroy(dc);
if (p != NULL)
free(p);
DefragDestroy();
return ret;
}
static int
DefragIPv4TooLargeTest(void)
{
DefragContext *dc = NULL;
Packet *p = NULL;
int ret = 0;
DefragInit();
dc = DefragContextNew();
if (dc == NULL)
goto end;
/* Create a fragment that would extend past the max allowable size
* for an IPv4 packet. */
p = BuildTestPacket(1, 8183, 0, 'A', 71);
if (p == NULL)
goto end;
/* We do not expect a packet returned. */
if (Defrag(NULL, dc, p) != NULL)
goto end;
/* The fragment should have been ignored so no fragments should have
* been allocated from the pool. */
if (dc->frag_pool->outstanding != 0)
return 0;
ret = 1;
end:
if (dc != NULL)
DefragContextDestroy(dc);
if (p != NULL)
free(p);
DefragDestroy();
return ret;
}
#endif /* UNITTESTS */
void
DefragRegisterTests(void)
{
#ifdef UNITTESTS
UtRegisterTest("DefragInOrderSimpleTest",
DefragInOrderSimpleTest, 1);
UtRegisterTest("DefragReverseSimpleTest",
DefragReverseSimpleTest, 1);
UtRegisterTest("DefragSturgesNovakBsdTest",
DefragSturgesNovakBsdTest, 1);
UtRegisterTest("DefragSturgesNovakLinuxTest",
DefragSturgesNovakLinuxTest, 1);
UtRegisterTest("DefragSturgesNovakWindowsTest",
DefragSturgesNovakWindowsTest, 1);
UtRegisterTest("DefragSturgesNovakSolarisTest",
DefragSturgesNovakSolarisTest, 1);
UtRegisterTest("DefragSturgesNovakFirstTest",
DefragSturgesNovakFirstTest, 1);
UtRegisterTest("DefragSturgesNovakLastTest",
DefragSturgesNovakLastTest, 1);
UtRegisterTest("DefragIPv4NoDataTest", DefragIPv4NoDataTest, 1);
UtRegisterTest("DefragIPv4TooLargeTest", DefragIPv4TooLargeTest, 1);
UtRegisterTest("IPV6DefragInOrderSimpleTest",
IPV6DefragInOrderSimpleTest, 1);
UtRegisterTest("IPV6DefragReverseSimpleTest",
IPV6DefragReverseSimpleTest, 1);
UtRegisterTest("IPV6DefragSturgesNovakBsdTest",
IPV6DefragSturgesNovakBsdTest, 1);
UtRegisterTest("IPV6DefragSturgesNovakLinuxTest",
IPV6DefragSturgesNovakLinuxTest, 1);
UtRegisterTest("IPV6DefragSturgesNovakWindowsTest",
IPV6DefragSturgesNovakWindowsTest, 1);
UtRegisterTest("IPV6DefragSturgesNovakSolarisTest",
IPV6DefragSturgesNovakSolarisTest, 1);
UtRegisterTest("IPV6DefragSturgesNovakFirstTest",
IPV6DefragSturgesNovakFirstTest, 1);
UtRegisterTest("IPV6DefragSturgesNovakLastTest",
IPV6DefragSturgesNovakLastTest, 1);
UtRegisterTest("DefragTimeoutTest",
DefragTimeoutTest, 1);
#endif /* UNITTESTS */
}