suricata
detect-http-stat-code.c
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1 /* Copyright (C) 2007-2018 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  * \ingroup httplayer
20  *
21  * @{
22  */
23 
24 
25 /**
26  * \file
27  *
28  * \author Gurvinder Singh <gurvindersinghdahiya@gmail.com>
29  * \author Anoop Saldanha <anoopsaldanha@gmail.com>
30  *
31  * Implements the http_stat_code keyword
32  */
33 
34 #include "suricata-common.h"
35 #include "threads.h"
36 #include "decode.h"
37 #include "detect.h"
38 
39 #include "detect-parse.h"
40 #include "detect-engine.h"
41 #include "detect-content.h"
42 #include "detect-pcre.h"
43 #include "detect-engine-mpm.h"
44 #include "detect-engine-prefilter.h"
45 
46 #include "flow.h"
47 #include "flow-var.h"
48 #include "flow-util.h"
49 
50 #include "util-debug.h"
51 #include "util-error.h"
52 #include "util-unittest.h"
53 #include "util-unittest-helper.h"
54 #include "util-spm.h"
55 #include "util-print.h"
56 
57 #include "app-layer.h"
58 #include "app-layer-parser.h"
59 
60 #include "app-layer-htp.h"
61 #include "detect-http-stat-code.h"
62 #include "stream-tcp-private.h"
63 #include "stream-tcp.h"
64 
65 static int DetectHttpStatCodeSetup(DetectEngineCtx *, Signature *, const char *);
66 static int DetectHttpStatCodeSetupSticky(DetectEngineCtx *de_ctx, Signature *s, const char *str);
67 #ifdef UNITTESTS
68 static void DetectHttpStatCodeRegisterTests(void);
69 #endif
70 static int g_http_stat_code_buffer_id = 0;
71 static InspectionBuffer *GetData(DetectEngineThreadCtx *det_ctx,
72  const DetectEngineTransforms *transforms, Flow *_f,
73  const uint8_t _flow_flags, void *txv, const int list_id);
74 static InspectionBuffer *GetData2(DetectEngineThreadCtx *det_ctx,
75  const DetectEngineTransforms *transforms, Flow *_f, const uint8_t _flow_flags, void *txv,
76  const int list_id);
77 
78 /**
79  * \brief Registration function for keyword: http_stat_code
80  */
81 void DetectHttpStatCodeRegister (void)
82 {
83  /* http_stat_code content modifier */
84  sigmatch_table[DETECT_AL_HTTP_STAT_CODE].name = "http_stat_code";
85  sigmatch_table[DETECT_AL_HTTP_STAT_CODE].desc = "content modifier to match only on HTTP stat-code-buffer";
86  sigmatch_table[DETECT_AL_HTTP_STAT_CODE].url = "/rules/http-keywords.html#http-stat-code";
87  sigmatch_table[DETECT_AL_HTTP_STAT_CODE].Setup = DetectHttpStatCodeSetup;
88 #ifdef UNITTESTS
89  sigmatch_table[DETECT_AL_HTTP_STAT_CODE].RegisterTests = DetectHttpStatCodeRegisterTests;
90 #endif
91  sigmatch_table[DETECT_AL_HTTP_STAT_CODE].flags |= SIGMATCH_NOOPT|SIGMATCH_INFO_CONTENT_MODIFIER;
92  sigmatch_table[DETECT_AL_HTTP_STAT_CODE].alternative = DETECT_HTTP_STAT_CODE;
93 
94  /* http.stat_code content modifier */
95  sigmatch_table[DETECT_HTTP_STAT_CODE].name = "http.stat_code";
96  sigmatch_table[DETECT_HTTP_STAT_CODE].desc = "sticky buffer to match only on HTTP stat-code-buffer";
97  sigmatch_table[DETECT_HTTP_STAT_CODE].url = "/rules/http-keywords.html#http-stat-code";
98  sigmatch_table[DETECT_HTTP_STAT_CODE].Setup = DetectHttpStatCodeSetupSticky;
99  sigmatch_table[DETECT_HTTP_STAT_CODE].flags |= SIGMATCH_NOOPT|SIGMATCH_INFO_STICKY_BUFFER;
100 
101  DetectAppLayerInspectEngineRegister("http_stat_code", ALPROTO_HTTP1, SIG_FLAG_TOCLIENT,
102  HTP_RESPONSE_LINE, DetectEngineInspectBufferGeneric, GetData);
103 
104  DetectAppLayerMpmRegister("http_stat_code", SIG_FLAG_TOCLIENT, 4, PrefilterGenericMpmRegister,
105  GetData, ALPROTO_HTTP1, HTP_RESPONSE_LINE);
106 
107  DetectAppLayerInspectEngineRegister("http_stat_code", ALPROTO_HTTP2, SIG_FLAG_TOCLIENT,
108  HTTP2StateDataServer, DetectEngineInspectBufferGeneric, GetData2);
109 
110  DetectAppLayerMpmRegister("http_stat_code", SIG_FLAG_TOCLIENT, 4, PrefilterGenericMpmRegister,
111  GetData2, ALPROTO_HTTP2, HTTP2StateDataServer);
112 
113  DetectBufferTypeSetDescriptionByName("http_stat_code",
114  "http response status code");
115 
116  g_http_stat_code_buffer_id = DetectBufferTypeGetByName("http_stat_code");
117 }
118 
119 /**
120  * \brief this function setups the http_stat_code modifier keyword used in the rule
121  *
122  * \param de_ctx Pointer to the Detection Engine Context
123  * \param s Pointer to the Signature to which the current keyword belongs
124  * \param str Should hold an empty string always
125  *
126  * \retval 0 On success
127  * \retval -1 On failure
128  */
129 
130 static int DetectHttpStatCodeSetup(DetectEngineCtx *de_ctx, Signature *s, const char *arg)
131 {
132  return DetectEngineContentModifierBufferSetup(
133  de_ctx, s, arg, DETECT_AL_HTTP_STAT_CODE, g_http_stat_code_buffer_id, ALPROTO_HTTP1);
134 }
135 
136 /**
137  * \brief this function setup the http.stat_code keyword used in the rule
138  *
139  * \param de_ctx Pointer to the Detection Engine Context
140  * \param s Pointer to the Signature to which the current keyword belongs
141  * \param str Should hold an empty string always
142  *
143  * \retval 0 On success
144  */
145 static int DetectHttpStatCodeSetupSticky(DetectEngineCtx *de_ctx, Signature *s, const char *str)
146 {
147  if (DetectBufferSetActiveList(de_ctx, s, g_http_stat_code_buffer_id) < 0)
148  return -1;
149  if (DetectSignatureSetAppProto(s, ALPROTO_HTTP) < 0)
150  return -1;
151  return 0;
152 }
153 
154 static InspectionBuffer *GetData(DetectEngineThreadCtx *det_ctx,
155  const DetectEngineTransforms *transforms, Flow *_f,
156  const uint8_t _flow_flags, void *txv, const int list_id)
157 {
158  SCEnter();
159 
160  InspectionBuffer *buffer = InspectionBufferGet(det_ctx, list_id);
161  if (buffer->inspect == NULL) {
162  htp_tx_t *tx = (htp_tx_t *)txv;
163 
164  if (tx->response_status == NULL)
165  return NULL;
166 
167  const uint32_t data_len = bstr_len(tx->response_status);
168  const uint8_t *data = bstr_ptr(tx->response_status);
169 
170  InspectionBufferSetup(det_ctx, list_id, buffer, data, data_len);
171  InspectionBufferApplyTransforms(buffer, transforms);
172  }
173 
174  return buffer;
175 }
176 
177 static InspectionBuffer *GetData2(DetectEngineThreadCtx *det_ctx,
178  const DetectEngineTransforms *transforms, Flow *_f, const uint8_t _flow_flags, void *txv,
179  const int list_id)
180 {
181  SCEnter();
182 
183  InspectionBuffer *buffer = InspectionBufferGet(det_ctx, list_id);
184  if (buffer->inspect == NULL) {
185  uint32_t b_len = 0;
186  const uint8_t *b = NULL;
187 
188  if (rs_http2_tx_get_status(txv, &b, &b_len) != 1)
189  return NULL;
190  if (b == NULL || b_len == 0)
191  return NULL;
192 
193  InspectionBufferSetup(det_ctx, list_id, buffer, b, b_len);
194  InspectionBufferApplyTransforms(buffer, transforms);
195  }
196 
197  return buffer;
198 }
199 
200 #ifdef UNITTESTS
201 #include "tests/detect-http-stat-code.c"
202 #endif /* UNITTESTS */
203 
204 /**
205  * @}
206  */
SigTableElmt_::url
const char * url
Definition: detect.h:1299
DetectSignatureSetAppProto
int DetectSignatureSetAppProto(Signature *s, AppProto alproto)
Definition: detect-parse.c:1753
detect-content.h
detect-engine.h
SIGMATCH_INFO_STICKY_BUFFER
#define SIGMATCH_INFO_STICKY_BUFFER
Definition: detect.h:1500
detect-http-stat-code.c
SigTableElmt_::desc
const char * desc
Definition: detect.h:1298
DetectEngineInspectBufferGeneric
uint8_t DetectEngineInspectBufferGeneric(DetectEngineCtx *de_ctx, DetectEngineThreadCtx *det_ctx, const DetectEngineAppInspectionEngine *engine, const Signature *s, Flow *f, uint8_t flags, void *alstate, void *txv, uint64_t tx_id)
Do the content inspection & validation for a signature.
Definition: detect-engine.c:2122
flow-util.h
SIGMATCH_INFO_CONTENT_MODIFIER
#define SIGMATCH_INFO_CONTENT_MODIFIER
Definition: detect.h:1498
SigTableElmt_::name
const char * name
Definition: detect.h:1296
DetectHttpStatCodeRegisterTests
void DetectHttpStatCodeRegisterTests(void)
Register the UNITTESTS for the http_stat_code keyword.
Definition: detect-http-stat-code.c:2283
stream-tcp.h
DetectEngineTransforms
Definition: detect.h:409
DetectBufferSetActiveList
int DetectBufferSetActiveList(DetectEngineCtx *de_ctx, Signature *s, const int list)
Definition: detect-engine.c:1335
InspectionBuffer
Definition: detect.h:374
threads.h
Flow_
Flow data structure.
Definition: flow.h:351
SigTableElmt_::flags
uint16_t flags
Definition: detect.h:1290
DetectEngineCtx_
main detection engine ctx
Definition: detect.h:839
SIG_FLAG_TOCLIENT
#define SIG_FLAG_TOCLIENT
Definition: detect.h:267
SigTableElmt_::Setup
int(* Setup)(DetectEngineCtx *, Signature *, const char *)
Definition: detect.h:1281
detect-pcre.h
detect-engine-prefilter.h
util-unittest.h
InspectionBufferGet
InspectionBuffer * InspectionBufferGet(DetectEngineThreadCtx *det_ctx, const int list_id)
Definition: detect-engine.c:1479
util-unittest-helper.h
DetectBufferTypeGetByName
int DetectBufferTypeGetByName(const char *name)
Definition: detect-engine.c:1072
app-layer-htp.h
decode.h
util-debug.h
util-error.h
de_ctx
DetectEngineCtx * de_ctx
Definition: fuzz_siginit.c:17
DetectEngineThreadCtx_
Definition: detect.h:1095
util-print.h
SCEnter
#define SCEnter(...)
Definition: util-debug.h:271
detect-engine-mpm.h
detect.h
PrefilterGenericMpmRegister
int PrefilterGenericMpmRegister(DetectEngineCtx *de_ctx, SigGroupHead *sgh, MpmCtx *mpm_ctx, const DetectBufferMpmRegistry *mpm_reg, int list_id)
Definition: detect-engine-prefilter.c:745
SigTableElmt_::alternative
uint16_t alternative
Definition: detect.h:1294
DetectAppLayerMpmRegister
void DetectAppLayerMpmRegister(const char *name, int direction, int priority, PrefilterRegisterFunc PrefilterRegister, InspectionBufferGetDataPtr GetData, AppProto alproto, int tx_min_progress)
register a MPM engine
Definition: detect-engine-mpm.c:89
app-layer-parser.h
DetectEngineContentModifierBufferSetup
int DetectEngineContentModifierBufferSetup(DetectEngineCtx *de_ctx, Signature *s, const char *arg, int sm_type, int sm_list, AppProto alproto)
Definition: detect-parse.c:205
stream-tcp-private.h
detect-http-stat-code.h
ALPROTO_HTTP2
@ ALPROTO_HTTP2
Definition: app-layer-protos.h:62
DETECT_HTTP_STAT_CODE
@ DETECT_HTTP_STAT_CODE
Definition: detect-engine-register.h:163
DETECT_AL_HTTP_STAT_CODE
@ DETECT_AL_HTTP_STAT_CODE
Definition: detect-engine-register.h:162
DetectHttpStatCodeRegister
void DetectHttpStatCodeRegister(void)
Registration function for keyword: http_stat_code.
Definition: detect-http-stat-code.c:81
suricata-common.h
InspectionBufferApplyTransforms
void InspectionBufferApplyTransforms(InspectionBuffer *buffer, const DetectEngineTransforms *transforms)
Definition: detect-engine.c:1678
ALPROTO_HTTP1
@ ALPROTO_HTTP1
Definition: app-layer-protos.h:30
sigmatch_table
SigTableElmt sigmatch_table[DETECT_TBLSIZE]
Definition: detect-parse.c:127
util-spm.h
InspectionBuffer::inspect
const uint8_t * inspect
Definition: detect.h:375
str
#define str(s)
Definition: suricata-common.h:291
InspectionBufferSetup
void InspectionBufferSetup(DetectEngineThreadCtx *det_ctx, const int list_id, InspectionBuffer *buffer, const uint8_t *data, const uint32_t data_len)
setup the buffer with our initial data
Definition: detect-engine.c:1574
detect-parse.h
Signature_
Signature container.
Definition: detect.h:596
ALPROTO_HTTP
@ ALPROTO_HTTP
Definition: app-layer-protos.h:67
SIGMATCH_NOOPT
#define SIGMATCH_NOOPT
Definition: detect.h:1476
DetectAppLayerInspectEngineRegister
void DetectAppLayerInspectEngineRegister(const char *name, AppProto alproto, uint32_t dir, int progress, InspectEngineFuncPtr Callback, InspectionBufferGetDataPtr GetData)
register inspect engine at start up time
Definition: detect-engine.c:169
DetectBufferTypeSetDescriptionByName
void DetectBufferTypeSetDescriptionByName(const char *name, const char *desc)
Definition: detect-engine.c:1169
flow.h
flow-var.h
SigTableElmt_::RegisterTests
void(* RegisterTests)(void)
Definition: detect.h:1288
app-layer.h