suricata
detect-uricontent.c
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1 /* Copyright (C) 2007-2022 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  * \file
20  *
21  * \author Victor Julien <victor@inliniac.net>
22  * \author Gurvinder Singh <gurvindersinghdahiya@gmail.com>
23  *
24  * Simple uricontent match part of the detection engine.
25  */
26 
27 #include "suricata-common.h"
28 #include "decode.h"
29 #include "detect.h"
30 #include "detect-content.h"
31 #include "detect-http-uri.h"
32 #include "detect-uricontent.h"
33 #include "detect-engine-mpm.h"
34 #include "detect-parse.h"
35 #include "detect-engine.h"
36 #include "detect-engine-state.h"
37 #include "flow.h"
38 #include "detect-flow.h"
39 #include "flow-var.h"
40 #include "flow-util.h"
41 #include "threads.h"
42 
43 #include "stream-tcp.h"
44 #include "stream.h"
45 #include "app-layer.h"
46 #include "app-layer-parser.h"
47 #include "app-layer-protos.h"
48 #include "app-layer-htp.h"
49 
50 #include "util-mpm.h"
51 #include "util-print.h"
52 #include "util-debug.h"
53 #include "util-unittest.h"
54 #include "util-unittest-helper.h"
55 #include "util-spm.h"
56 #include "conf.h"
57 
58 /* prototypes */
59 static int DetectUricontentSetup(DetectEngineCtx *, Signature *, const char *);
60 static void DetectUricontentFree(DetectEngineCtx *de_ctx, void *);
61 
62 static int g_http_uri_buffer_id = 0;
63 
64 /**
65  * \brief Registration function for uricontent: keyword
66  */
68 {
69  sigmatch_table[DETECT_URICONTENT].name = "uricontent";
70  sigmatch_table[DETECT_URICONTENT].desc = "legacy keyword to match on the request URI buffer";
71  sigmatch_table[DETECT_URICONTENT].url = "/rules/http-keywords.html#uricontent";
73  sigmatch_table[DETECT_URICONTENT].Setup = DetectUricontentSetup;
74  sigmatch_table[DETECT_URICONTENT].Free = DetectUricontentFree;
77 
78  g_http_uri_buffer_id = DetectBufferTypeRegister("http_uri");
79 }
80 
81 /**
82  * \brief this function will Free memory associated with DetectContentData
83  *
84  * \param cd pointer to DetectUricontentData
85  */
86 void DetectUricontentFree(DetectEngineCtx *de_ctx, void *ptr)
87 {
88  SCEnter();
90 
91  if (cd == NULL)
92  SCReturn;
93 
95  SCFree(cd);
96 
97  SCReturn;
98 }
99 
100 /**
101  * \brief Creates a SigMatch for the uricontent keyword being sent as argument,
102  * and appends it to the Signature(s).
103  *
104  * \param de_ctx Pointer to the detection engine context
105  * \param s Pointer to signature for the current Signature being parsed
106  * from the rules
107  * \param contentstr Pointer to the string holding the keyword value
108  *
109  * \retval 0 on success, -1 on failure
110  */
111 int DetectUricontentSetup(DetectEngineCtx *de_ctx, Signature *s, const char *contentstr)
112 {
113  SCEnter();
114 
115  const char *legacy = NULL;
116  if (ConfGet("legacy.uricontent", &legacy) == 1) {
117  if (strcasecmp("disabled", legacy) == 0) {
118  SCLogError("uricontent deprecated. To "
119  "use a rule with \"uricontent\", either set the "
120  "option - \"legacy.uricontent\" in the conf to "
121  "\"enabled\" OR replace uricontent with "
122  "\'content:%s; http_uri;\'.",
123  contentstr);
124  goto error;
125  } else if (strcasecmp("enabled", legacy) == 0) {
126  ;
127  } else {
128  SCLogError("Invalid value found "
129  "for legacy.uricontent - \"%s\". Valid values are "
130  "\"enabled\" OR \"disabled\".",
131  legacy);
132  goto error;
133  }
134  }
135 
136  if (DetectContentSetup(de_ctx, s, contentstr) < 0)
137  goto error;
138 
139  if (DetectHttpUriSetup(de_ctx, s, NULL) < 0)
140  goto error;
141 
142  SCReturnInt(0);
143 error:
144  SCReturnInt(-1);
145 }
SigTableElmt_::url
const char * url
Definition: detect.h:1296
detect-content.h
detect-engine.h
SigTableElmt_::desc
const char * desc
Definition: detect.h:1295
SigTableElmt_::Free
void(* Free)(DetectEngineCtx *, void *)
Definition: detect.h:1283
flow-util.h
SigTableElmt_::name
const char * name
Definition: detect.h:1293
stream-tcp.h
threads.h
SigTableElmt_::flags
uint16_t flags
Definition: detect.h:1287
DetectEngineCtx_
main detection engine ctx
Definition: detect.h:836
DetectContentData_
Definition: detect-content.h:93
DetectUricontentRegister
void DetectUricontentRegister(void)
Registration function for uricontent: keyword.
Definition: detect-uricontent.c:67
SigTableElmt_::Setup
int(* Setup)(DetectEngineCtx *, Signature *, const char *)
Definition: detect.h:1278
util-unittest.h
util-unittest-helper.h
DetectHttpUriSetup
int DetectHttpUriSetup(DetectEngineCtx *de_ctx, Signature *s, const char *str)
this function setups the http_uri modifier keyword used in the rule
Definition: detect-http-uri.c:184
ConfGet
int ConfGet(const char *name, const char **vptr)
Retrieve the value of a configuration node.
Definition: conf.c:335
SIGMATCH_QUOTES_MANDATORY
#define SIGMATCH_QUOTES_MANDATORY
Definition: detect.h:1489
app-layer-htp.h
decode.h
util-debug.h
de_ctx
DetectEngineCtx * de_ctx
Definition: fuzz_siginit.c:17
DetectContentSetup
int DetectContentSetup(DetectEngineCtx *de_ctx, Signature *s, const char *contentstr)
Function to setup a content pattern.
Definition: detect-content.c:328
DETECT_URICONTENT
@ DETECT_URICONTENT
Definition: detect-engine-register.h:63
util-print.h
SCEnter
#define SCEnter(...)
Definition: util-debug.h:271
detect-engine-mpm.h
detect.h
detect-http-uri.h
SigTableElmt_::alternative
uint16_t alternative
Definition: detect.h:1291
app-layer-parser.h
SCReturn
#define SCReturn
Definition: util-debug.h:273
stream.h
conf.h
SIGMATCH_HANDLE_NEGATION
#define SIGMATCH_HANDLE_NEGATION
Definition: detect.h:1493
detect-engine-state.h
Data structures and function prototypes for keeping state for the detection engine.
SigTableElmt_::Match
int(* Match)(DetectEngineThreadCtx *, Packet *, const Signature *, const SigMatchCtx *)
Definition: detect.h:1261
util-mpm.h
DetectBufferTypeRegister
int DetectBufferTypeRegister(const char *name)
Definition: detect-engine.c:1055
suricata-common.h
sigmatch_table
SigTableElmt sigmatch_table[DETECT_TBLSIZE]
Definition: detect-parse.c:127
util-spm.h
detect-flow.h
DetectContentData_::spm_ctx
SpmCtx * spm_ctx
Definition: detect-content.h:111
SCLogError
#define SCLogError(...)
Macro used to log ERROR messages.
Definition: util-debug.h:261
SCFree
#define SCFree(p)
Definition: util-mem.h:61
detect-parse.h
Signature_
Signature container.
Definition: detect.h:593
app-layer-protos.h
detect-uricontent.h
flow.h
SpmDestroyCtx
void SpmDestroyCtx(SpmCtx *ctx)
Definition: util-spm.c:183
SCReturnInt
#define SCReturnInt(x)
Definition: util-debug.h:275
flow-var.h
DETECT_HTTP_URI
@ DETECT_HTTP_URI
Definition: detect-engine-register.h:157
app-layer.h