1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
|
/* Copyright (C) 2022 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.
*/
#include "suricata-common.h"
#include "rust.h"
#include "detect-flow-age.h"
#include "detect-engine.h"
#include "detect-engine-prefilter.h"
#include "detect-engine-uint.h"
#include "detect-parse.h"
static int DetectFlowAgeMatch(
DetectEngineThreadCtx *det_ctx, Packet *p, const Signature *s, const SigMatchCtx *ctx)
{
if (p->flow == NULL) {
return 0;
}
uint32_t age = SCTIME_SECS(p->flow->lastts) - SCTIME_SECS(p->flow->startts);
const DetectU32Data *du32 = (const DetectU32Data *)ctx;
return DetectU32Match(age, du32);
}
static void DetectFlowAgeFree(DetectEngineCtx *de_ctx, void *ptr)
{
rs_detect_u32_free(ptr);
}
static int DetectFlowAgeSetup(DetectEngineCtx *de_ctx, Signature *s, const char *rawstr)
{
DetectU32Data *du32 = DetectU32Parse(rawstr);
if (du32 == NULL)
return -1;
SigMatch *sm = SigMatchAlloc();
if (sm == NULL) {
DetectFlowAgeFree(de_ctx, du32);
return -1;
}
sm->type = DETECT_FLOW_AGE;
sm->ctx = (SigMatchCtx *)du32;
SigMatchAppendSMToList(s, sm, DETECT_SM_LIST_MATCH);
s->flags |= SIG_FLAG_REQUIRE_PACKET;
return 0;
}
static void PrefilterPacketFlowAgeMatch(
DetectEngineThreadCtx *det_ctx, Packet *p, const void *pectx)
{
const PrefilterPacketHeaderCtx *ctx = pectx;
if (!PrefilterPacketHeaderExtraMatch(ctx, p))
return;
DetectU32Data du32;
du32.mode = ctx->v1.u8[0];
du32.arg1 = ctx->v1.u32[1];
du32.arg2 = ctx->v1.u32[2];
if (DetectFlowAgeMatch(det_ctx, p, NULL, (const SigMatchCtx *)&du32)) {
PrefilterAddSids(&det_ctx->pmq, ctx->sigs_array, ctx->sigs_cnt);
}
}
static int PrefilterSetupFlowAge(DetectEngineCtx *de_ctx, SigGroupHead *sgh)
{
return PrefilterSetupPacketHeader(de_ctx, sgh, DETECT_FLOW_AGE, PrefilterPacketU32Set,
PrefilterPacketU32Compare, PrefilterPacketFlowAgeMatch);
}
static bool PrefilterFlowAgeIsPrefilterable(const Signature *s)
{
return PrefilterIsPrefilterableById(s, DETECT_FLOW_AGE);
}
void DetectFlowAgeRegister(void)
{
sigmatch_table[DETECT_FLOW_AGE].name = "flow.age";
sigmatch_table[DETECT_FLOW_AGE].desc = "match flow age";
sigmatch_table[DETECT_FLOW_AGE].url = "/rules/flow-keywords.html#flow-age";
sigmatch_table[DETECT_FLOW_AGE].Match = DetectFlowAgeMatch;
sigmatch_table[DETECT_FLOW_AGE].Setup = DetectFlowAgeSetup;
sigmatch_table[DETECT_FLOW_AGE].Free = DetectFlowAgeFree;
sigmatch_table[DETECT_FLOW_AGE].SupportsPrefilter = PrefilterFlowAgeIsPrefilterable;
sigmatch_table[DETECT_FLOW_AGE].SetupPrefilter = PrefilterSetupFlowAge;
}
|
