suricata
detect-ike-key-exchange-payload-length.c
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1 /* Copyright (C) 2020 Open Information Security Foundation
2  *
3  * You can copy, redistribute or modify this Program under the terms of
4  * the GNU General Public License version 2 as published by the Free
5  * Software Foundation.
6  *
7  * This program is distributed in the hope that it will be useful,
8  * but WITHOUT ANY WARRANTY; without even the implied warranty of
9  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
10  * GNU General Public License for more details.
11  *
12  * You should have received a copy of the GNU General Public License
13  * version 2 along with this program; if not, write to the Free Software
14  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
15  * 02110-1301, USA.
16  */
17 
18 /**
19  *
20  * \author Frank Honza <frank.honza@dcso.de>
21  */
22 
23 #include "suricata-common.h"
24 #include "conf.h"
25 #include "detect.h"
26 #include "detect-parse.h"
27 #include "detect-engine.h"
30 #include "app-layer-parser.h"
31 #include "util-byte.h"
32 #include "detect-engine-uint.h"
33 
34 #include "rust-bindings.h"
35 
36 /**
37  * [ike.key_exchange_payload_length]:[=|<|>|<=|>=]<length>;
38  */
39 static int DetectIkeKeyExchangePayloadLengthSetup(DetectEngineCtx *, Signature *s, const char *str);
40 static void DetectIkeKeyExchangePayloadLengthFree(DetectEngineCtx *, void *);
41 static int g_ike_key_exch_payload_length_buffer_id = 0;
42 
43 static int DetectEngineInspectIkeKeyExchangePayloadLengthGeneric(DetectEngineCtx *de_ctx,
44  DetectEngineThreadCtx *det_ctx, const struct DetectEngineAppInspectionEngine_ *engine,
45  const Signature *s, Flow *f, uint8_t flags, void *alstate, void *txv, uint64_t tx_id);
46 
47 static int DetectIkeKeyExchangePayloadLengthMatch(DetectEngineThreadCtx *, Flow *, uint8_t, void *,
48  void *, const Signature *, const SigMatchCtx *);
49 
50 /**
51  * \brief Registration function for ike.key_exchange_payload_length keyword.
52  */
54 {
56  "ike.key_exchange_payload_length";
58  "match IKE key exchange payload length";
60  "/rules/ike-keywords.html#ike-key-exchange-payload-length";
62  DetectIkeKeyExchangePayloadLengthMatch;
64  DetectIkeKeyExchangePayloadLengthSetup;
66  DetectIkeKeyExchangePayloadLengthFree;
67 
68  DetectAppLayerInspectEngineRegister2("ike.key_exchange_payload_length", ALPROTO_IKE,
69  SIG_FLAG_TOSERVER, 1, DetectEngineInspectIkeKeyExchangePayloadLengthGeneric, NULL);
70 
71  DetectAppLayerInspectEngineRegister2("ike.key_exchange_payload_length", ALPROTO_IKE,
72  SIG_FLAG_TOCLIENT, 1, DetectEngineInspectIkeKeyExchangePayloadLengthGeneric, NULL);
73 
74  g_ike_key_exch_payload_length_buffer_id =
75  DetectBufferTypeGetByName("ike.key_exchange_payload_length");
76 
78 }
79 
80 static int DetectEngineInspectIkeKeyExchangePayloadLengthGeneric(DetectEngineCtx *de_ctx,
81  DetectEngineThreadCtx *det_ctx, const struct DetectEngineAppInspectionEngine_ *engine,
82  const Signature *s, Flow *f, uint8_t flags, void *alstate, void *txv, uint64_t tx_id)
83 {
85  de_ctx, det_ctx, s, engine->smd, f, flags, alstate, txv, tx_id);
86 }
87 
88 /**
89  * \internal
90  * \brief Function to match key exchange payload length of a IKE state
91  *
92  * \param det_ctx Pointer to the pattern matcher thread.
93  * \param f Pointer to the current flow.
94  * \param flags Flags.
95  * \param state App layer state.
96  * \param txv Pointer to the Ike Transaction.
97  * \param s Pointer to the Signature.
98  * \param ctx Pointer to the sigmatch that we will cast into DetectU32Data.
99  *
100  * \retval 0 no match.
101  * \retval 1 match.
102  */
103 static int DetectIkeKeyExchangePayloadLengthMatch(DetectEngineThreadCtx *det_ctx, Flow *f,
104  uint8_t flags, void *state, void *txv, const Signature *s, const SigMatchCtx *ctx)
105 {
106  SCEnter();
107 
108  uint32_t length;
109  if (!rs_ike_state_get_key_exchange_payload_length(txv, &length))
110  SCReturnInt(0);
111  const DetectU32Data *du32 = (const DetectU32Data *)ctx;
112  return DetectU32Match(length, du32);
113 }
114 
115 /**
116  * \brief Function to add the parsed IKE key exchange payload length query into the current
117  * signature.
118  *
119  * \param de_ctx Pointer to the Detection Engine Context.
120  * \param s Pointer to the Current Signature.
121  * \param rawstr Pointer to the user provided flags options.
122  *
123  * \retval 0 on Success.
124  * \retval -1 on Failure.
125  */
126 static int DetectIkeKeyExchangePayloadLengthSetup(
127  DetectEngineCtx *de_ctx, Signature *s, const char *rawstr)
128 {
130  return -1;
131 
132  DetectU32Data *key_exchange_payload_length = DetectU32Parse(rawstr);
133  if (key_exchange_payload_length == NULL)
134  return -1;
135 
136  /* okay so far so good, lets get this into a SigMatch
137  * and put it in the Signature. */
138  SigMatch *sm = SigMatchAlloc();
139  if (sm == NULL)
140  goto error;
141 
143  sm->ctx = (SigMatchCtx *)key_exchange_payload_length;
144 
145  SigMatchAppendSMToList(s, sm, g_ike_key_exch_payload_length_buffer_id);
146  return 0;
147 
148 error:
149  DetectIkeKeyExchangePayloadLengthFree(de_ctx, key_exchange_payload_length);
150  return -1;
151 }
152 
153 /**
154  * \internal
155  * \brief Function to free memory associated with DetectU32Data.
156  *
157  * \param de_ptr Pointer to DetectU32Data.
158  */
159 static void DetectIkeKeyExchangePayloadLengthFree(DetectEngineCtx *de_ctx, void *ptr)
160 {
161  SCFree(ptr);
162 }
util-byte.h
detect-engine-uint.h
DetectEngineAppInspectionEngine_
Definition: detect.h:397
SigTableElmt_::url
const char * url
Definition: detect.h:1204
DetectSignatureSetAppProto
int DetectSignatureSetAppProto(Signature *s, AppProto alproto)
Definition: detect-parse.c:1489
detect-engine.h
ALPROTO_IKE
@ ALPROTO_IKE
Definition: app-layer-protos.h:49
SigTableElmt_::desc
const char * desc
Definition: detect.h:1203
SigTableElmt_::Free
void(* Free)(DetectEngineCtx *, void *)
Definition: detect.h:1191
DetectEngineInspectGenericList
int DetectEngineInspectGenericList(const DetectEngineCtx *de_ctx, DetectEngineThreadCtx *det_ctx, const Signature *s, const SigMatchData *smd, Flow *f, const uint8_t flags, void *alstate, void *txv, uint64_t tx_id)
Do the content inspection & validation for a signature.
Definition: detect-engine.c:1575
SigTableElmt_::name
const char * name
Definition: detect.h:1201
Flow_
Flow data structure.
Definition: flow.h:353
DetectEngineCtx_
main detection engine ctx
Definition: detect.h:758
SigTableElmt_::AppLayerTxMatch
int(* AppLayerTxMatch)(DetectEngineThreadCtx *, Flow *, uint8_t flags, void *alstate, void *txv, const Signature *, const SigMatchCtx *)
Definition: detect.h:1172
DetectU32Parse
DetectU32Data * DetectU32Parse(const char *u32str)
This function is used to parse u32 options passed via some u32 keyword.
Definition: detect-engine-uint.c:115
SIG_FLAG_TOCLIENT
#define SIG_FLAG_TOCLIENT
Definition: detect.h:237
SigTableElmt_::Setup
int(* Setup)(DetectEngineCtx *, Signature *, const char *)
Definition: detect.h:1186
DetectBufferTypeGetByName
int DetectBufferTypeGetByName(const char *name)
Definition: detect-engine.c:829
SIG_FLAG_TOSERVER
#define SIG_FLAG_TOSERVER
Definition: detect.h:236
DetectU32Match
int DetectU32Match(const uint32_t parg, const DetectU32Data *du32)
Definition: detect-engine-uint.c:39
de_ctx
DetectEngineCtx * de_ctx
Definition: fuzz_siginit.c:17
DetectEngineThreadCtx_
Definition: detect.h:1003
SCEnter
#define SCEnter(...)
Definition: util-debug.h:300
detect.h
app-layer-parser.h
SigMatch_::ctx
SigMatchCtx * ctx
Definition: detect.h:323
DetectAppLayerInspectEngineRegister2
void DetectAppLayerInspectEngineRegister2(const char *name, AppProto alproto, uint32_t dir, int progress, InspectEngineFuncPtr2 Callback2, InspectionBufferGetDataPtr GetData)
register inspect engine at start up time
Definition: detect-engine.c:174
conf.h
SigMatchAlloc
SigMatch * SigMatchAlloc(void)
Definition: detect-parse.c:235
SigMatch_::type
uint8_t type
Definition: detect.h:321
detect-engine-content-inspection.h
SigMatchCtx_
Used to start a pointer to SigMatch context Should never be dereferenced without casting to something...
Definition: detect.h:315
DetectEngineAppInspectionEngine_::smd
SigMatchData * smd
Definition: detect.h:414
DETECT_AL_IKE_KEY_EXCHANGE_PAYLOAD_LENGTH
@ DETECT_AL_IKE_KEY_EXCHANGE_PAYLOAD_LENGTH
Definition: detect-engine-register.h:307
flags
uint8_t flags
Definition: decode-gre.h:0
suricata-common.h
sigmatch_table
SigTableElmt sigmatch_table[DETECT_TBLSIZE]
Definition: detect-parse.c:73
str
#define str(s)
Definition: suricata-common.h:272
DetectU32Data_
Definition: detect-engine-uint.h:38
SCFree
#define SCFree(p)
Definition: util-mem.h:61
detect-parse.h
Signature_
Signature container.
Definition: detect.h:517
SigMatch_
a single match condition for a signature
Definition: detect.h:320
DetectUintRegister
void DetectUintRegister(void)
Definition: detect-engine-uint.c:284
detect-ike-key-exchange-payload-length.h
DetectIkeKeyExchangePayloadLengthRegister
void DetectIkeKeyExchangePayloadLengthRegister(void)
Registration function for ike.key_exchange_payload_length keyword.
Definition: detect-ike-key-exchange-payload-length.c:53
SCReturnInt
#define SCReturnInt(x)
Definition: util-debug.h:304
SigMatchAppendSMToList
void SigMatchAppendSMToList(Signature *s, SigMatch *new, int list)
Append a SigMatch to the list type.
Definition: detect-parse.c:349