suricata
detect-http-cookie.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  *
30  * Implements the http_cookie keyword
31  */
32 
33 #include "suricata-common.h"
34 #include "threads.h"
35 #include "decode.h"
36 #include "detect.h"
37 
38 #include "detect-parse.h"
39 #include "detect-engine.h"
40 #include "detect-engine-buffer.h"
41 #include "detect-engine-mpm.h"
42 #include "detect-engine-prefilter.h"
43 #include "detect-content.h"
44 #include "detect-pcre.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-cookie.h"
62 #include "stream-tcp.h"
63 
64 static int DetectHttpCookieSetup (DetectEngineCtx *, Signature *, const char *);
65 static int DetectHttpCookieSetupSticky (DetectEngineCtx *, Signature *, const char *);
66 #ifdef UNITTESTS
67 static void DetectHttpCookieRegisterTests(void);
68 #endif
69 static int g_http_cookie_buffer_id = 0;
70 
71 static InspectionBuffer *GetRequestData(DetectEngineThreadCtx *det_ctx,
72  const DetectEngineTransforms *transforms,
73  Flow *_f, const uint8_t _flow_flags,
74  void *txv, const int list_id);
75 static InspectionBuffer *GetResponseData(DetectEngineThreadCtx *det_ctx,
76  const DetectEngineTransforms *transforms,
77  Flow *_f, const uint8_t _flow_flags,
78  void *txv, const int list_id);
79 static InspectionBuffer *GetRequestData2(DetectEngineThreadCtx *det_ctx,
80  const DetectEngineTransforms *transforms, Flow *_f, const uint8_t _flow_flags, void *txv,
81  const int list_id);
82 static InspectionBuffer *GetResponseData2(DetectEngineThreadCtx *det_ctx,
83  const DetectEngineTransforms *transforms, Flow *_f, const uint8_t _flow_flags, void *txv,
84  const int list_id);
85 /**
86  * \brief Registration function for keyword: http_cookie
87  */
88 void DetectHttpCookieRegister(void)
89 {
90  /* http_cookie content modifier */
91  sigmatch_table[DETECT_HTTP_COOKIE_CM].name = "http_cookie";
92  sigmatch_table[DETECT_HTTP_COOKIE_CM].desc =
93  "content modifier to match only on the HTTP cookie-buffer";
94  sigmatch_table[DETECT_HTTP_COOKIE_CM].url = "/rules/http-keywords.html#http-cookie";
95  sigmatch_table[DETECT_HTTP_COOKIE_CM].Setup = DetectHttpCookieSetup;
96 #ifdef UNITTESTS
97  sigmatch_table[DETECT_HTTP_COOKIE_CM].RegisterTests = DetectHttpCookieRegisterTests;
98 #endif
99  sigmatch_table[DETECT_HTTP_COOKIE_CM].flags |= SIGMATCH_NOOPT;
100  sigmatch_table[DETECT_HTTP_COOKIE_CM].flags |= SIGMATCH_INFO_CONTENT_MODIFIER;
101  sigmatch_table[DETECT_HTTP_COOKIE_CM].alternative = DETECT_HTTP_COOKIE;
102 
103  /* http.cookie sticky buffer */
104  sigmatch_table[DETECT_HTTP_COOKIE].name = "http.cookie";
105  sigmatch_table[DETECT_HTTP_COOKIE].desc = "sticky buffer to match on the HTTP Cookie/Set-Cookie buffers";
106  sigmatch_table[DETECT_HTTP_COOKIE].url = "/rules/http-keywords.html#http-cookie";
107  sigmatch_table[DETECT_HTTP_COOKIE].Setup = DetectHttpCookieSetupSticky;
108  sigmatch_table[DETECT_HTTP_COOKIE].flags |= SIGMATCH_NOOPT;
109  sigmatch_table[DETECT_HTTP_COOKIE].flags |= SIGMATCH_INFO_STICKY_BUFFER;
110 
111  DetectAppLayerInspectEngineRegister("http_cookie", ALPROTO_HTTP1, SIG_FLAG_TOSERVER,
112  HTP_REQUEST_PROGRESS_HEADERS, DetectEngineInspectBufferGeneric, GetRequestData);
113  DetectAppLayerInspectEngineRegister("http_cookie", ALPROTO_HTTP1, SIG_FLAG_TOCLIENT,
114  HTP_REQUEST_PROGRESS_HEADERS, DetectEngineInspectBufferGeneric, GetResponseData);
115 
116  DetectAppLayerMpmRegister("http_cookie", SIG_FLAG_TOSERVER, 2, PrefilterGenericMpmRegister,
117  GetRequestData, ALPROTO_HTTP1, HTP_REQUEST_PROGRESS_HEADERS);
118  DetectAppLayerMpmRegister("http_cookie", SIG_FLAG_TOCLIENT, 2, PrefilterGenericMpmRegister,
119  GetResponseData, ALPROTO_HTTP1, HTP_REQUEST_PROGRESS_HEADERS);
120 
121  DetectAppLayerInspectEngineRegister("http_cookie", ALPROTO_HTTP2, SIG_FLAG_TOSERVER,
122  HTTP2StateDataClient, DetectEngineInspectBufferGeneric, GetRequestData2);
123  DetectAppLayerInspectEngineRegister("http_cookie", ALPROTO_HTTP2, SIG_FLAG_TOCLIENT,
124  HTTP2StateDataServer, DetectEngineInspectBufferGeneric, GetResponseData2);
125 
126  DetectAppLayerMpmRegister("http_cookie", SIG_FLAG_TOSERVER, 2, PrefilterGenericMpmRegister,
127  GetRequestData2, ALPROTO_HTTP2, HTTP2StateDataClient);
128  DetectAppLayerMpmRegister("http_cookie", SIG_FLAG_TOCLIENT, 2, PrefilterGenericMpmRegister,
129  GetResponseData2, ALPROTO_HTTP2, HTTP2StateDataServer);
130 
131  DetectBufferTypeSetDescriptionByName("http_cookie",
132  "http cookie header");
133 
134  g_http_cookie_buffer_id = DetectBufferTypeGetByName("http_cookie");
135 }
136 
137 /**
138  * \brief this function setups the http_cookie modifier keyword used in the rule
139  *
140  * \param de_ctx Pointer to the Detection Engine Context
141  * \param s Pointer to the Signature to which the current keyword belongs
142  * \param str Should hold an empty string always
143  *
144  * \retval 0 On success
145  * \retval -1 On failure
146  */
147 
148 static int DetectHttpCookieSetup(DetectEngineCtx *de_ctx, Signature *s, const char *str)
149 {
150  return DetectEngineContentModifierBufferSetup(
151  de_ctx, s, str, DETECT_HTTP_COOKIE_CM, g_http_cookie_buffer_id, ALPROTO_HTTP1);
152 }
153 
154 /**
155  * \brief this function setup the http.cookie keyword used in the rule
156  *
157  * \param de_ctx Pointer to the Detection Engine Context
158  * \param s Pointer to the Signature to which the current keyword belongs
159  * \param str Should hold an empty string always
160  *
161  * \retval 0 On success
162  */
163 static int DetectHttpCookieSetupSticky(DetectEngineCtx *de_ctx, Signature *s, const char *str)
164 {
165  if (SCDetectBufferSetActiveList(de_ctx, s, g_http_cookie_buffer_id) < 0)
166  return -1;
167 
168  if (SCDetectSignatureSetAppProto(s, ALPROTO_HTTP) < 0)
169  return -1;
170 
171  return 0;
172 }
173 
174 static InspectionBuffer *GetRequestData(DetectEngineThreadCtx *det_ctx,
175  const DetectEngineTransforms *transforms, Flow *_f,
176  const uint8_t _flow_flags, void *txv, const int list_id)
177 {
178  InspectionBuffer *buffer = InspectionBufferGet(det_ctx, list_id);
179  if (buffer->inspect == NULL) {
180  htp_tx_t *tx = (htp_tx_t *)txv;
181 
182  if (htp_tx_request_headers(tx) == NULL)
183  return NULL;
184 
185  const htp_header_t *h = htp_tx_request_header(tx, "Cookie");
186  if (h == NULL || htp_header_value(h) == NULL) {
187  SCLogDebug("HTTP cookie header not present in this request");
188  return NULL;
189  }
190 
191  const uint32_t data_len = (uint32_t)htp_header_value_len(h);
192  const uint8_t *data = htp_header_value_ptr(h);
193 
194  InspectionBufferSetupAndApplyTransforms(
195  det_ctx, list_id, buffer, data, data_len, transforms);
196  }
197 
198  return buffer;
199 }
200 
201 static InspectionBuffer *GetResponseData(DetectEngineThreadCtx *det_ctx,
202  const DetectEngineTransforms *transforms, Flow *_f,
203  const uint8_t _flow_flags, void *txv, const int list_id)
204 {
205  InspectionBuffer *buffer = InspectionBufferGet(det_ctx, list_id);
206  if (buffer->inspect == NULL) {
207  htp_tx_t *tx = (htp_tx_t *)txv;
208 
209  if (htp_tx_response_headers(tx) == NULL)
210  return NULL;
211 
212  const htp_header_t *h = htp_tx_response_header(tx, "Set-Cookie");
213  if (h == NULL || htp_header_value(h) == NULL) {
214  SCLogDebug("HTTP cookie header not present in this request");
215  return NULL;
216  }
217 
218  const uint32_t data_len = (uint32_t)htp_header_value_len(h);
219  const uint8_t *data = htp_header_value_ptr(h);
220 
221  InspectionBufferSetupAndApplyTransforms(
222  det_ctx, list_id, buffer, data, data_len, transforms);
223  }
224 
225  return buffer;
226 }
227 
228 static InspectionBuffer *GetRequestData2(DetectEngineThreadCtx *det_ctx,
229  const DetectEngineTransforms *transforms, Flow *_f, const uint8_t _flow_flags, void *txv,
230  const int list_id)
231 {
232  InspectionBuffer *buffer = InspectionBufferGet(det_ctx, list_id);
233  if (buffer->inspect == NULL) {
234  uint32_t b_len = 0;
235  const uint8_t *b = NULL;
236 
237  if (SCHttp2TxGetCookie(txv, STREAM_TOSERVER, &b, &b_len) != 1)
238  return NULL;
239  if (b == NULL || b_len == 0)
240  return NULL;
241 
242  InspectionBufferSetupAndApplyTransforms(det_ctx, list_id, buffer, b, b_len, transforms);
243  }
244 
245  return buffer;
246 }
247 
248 static InspectionBuffer *GetResponseData2(DetectEngineThreadCtx *det_ctx,
249  const DetectEngineTransforms *transforms, Flow *_f, const uint8_t _flow_flags, void *txv,
250  const int list_id)
251 {
252  InspectionBuffer *buffer = InspectionBufferGet(det_ctx, list_id);
253  if (buffer->inspect == NULL) {
254  uint32_t b_len = 0;
255  const uint8_t *b = NULL;
256 
257  if (SCHttp2TxGetCookie(txv, STREAM_TOCLIENT, &b, &b_len) != 1)
258  return NULL;
259  if (b == NULL || b_len == 0)
260  return NULL;
261 
262  InspectionBufferSetupAndApplyTransforms(det_ctx, list_id, buffer, b, b_len, transforms);
263  }
264 
265  return buffer;
266 }
267 
268 /******************************** UNITESTS **********************************/
269 
270 #ifdef UNITTESTS
271 #include "tests/detect-http-cookie.c"
272 #endif /* UNITTESTS */
273 
274 /**
275  * @}
276  */
SigTableElmt_::url
const char * url
Definition: detect.h:1462
detect-content.h
detect-engine.h
SIGMATCH_INFO_STICKY_BUFFER
#define SIGMATCH_INFO_STICKY_BUFFER
Definition: detect.h:1676
SigTableElmt_::desc
const char * desc
Definition: detect.h:1461
sigmatch_table
SigTableElmt * sigmatch_table
Definition: detect-parse.c:79
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:2057
flow-util.h
SIGMATCH_INFO_CONTENT_MODIFIER
#define SIGMATCH_INFO_CONTENT_MODIFIER
Definition: detect.h:1674
SigTableElmt_::name
const char * name
Definition: detect.h:1459
stream-tcp.h
DetectEngineTransforms
Definition: detect.h:391
SCLogDebug
#define SCLogDebug(...)
Definition: util-debug.h:275
InspectionBuffer
Definition: detect-engine-inspect-buffer.h:34
threads.h
Flow_
Flow data structure.
Definition: flow.h:356
SigTableElmt_::flags
uint16_t flags
Definition: detect.h:1450
DetectEngineCtx_
main detection engine ctx
Definition: detect.h:932
DETECT_HTTP_COOKIE_CM
@ DETECT_HTTP_COOKIE_CM
Definition: detect-engine-register.h:150
SCDetectBufferSetActiveList
int SCDetectBufferSetActiveList(DetectEngineCtx *de_ctx, Signature *s, const int list)
Definition: detect-engine-buffer.c:29
SCDetectSignatureSetAppProto
int SCDetectSignatureSetAppProto(Signature *s, AppProto alproto)
Definition: detect-parse.c:2229
SIG_FLAG_TOCLIENT
#define SIG_FLAG_TOCLIENT
Definition: detect.h:272
InspectionBufferGet
InspectionBuffer * InspectionBufferGet(DetectEngineThreadCtx *det_ctx, const int list_id)
Definition: detect-engine-inspect-buffer.c:56
SigTableElmt_::Setup
int(* Setup)(DetectEngineCtx *, Signature *, const char *)
Definition: detect.h:1441
detect-pcre.h
detect-engine-prefilter.h
util-unittest.h
util-unittest-helper.h
DetectBufferTypeGetByName
int DetectBufferTypeGetByName(const char *name)
Definition: detect-engine.c:1277
SIG_FLAG_TOSERVER
#define SIG_FLAG_TOSERVER
Definition: detect.h:271
app-layer-htp.h
decode.h
util-debug.h
util-error.h
de_ctx
DetectEngineCtx * de_ctx
Definition: fuzz_siginit.c:18
DetectEngineThreadCtx_
Definition: detect.h:1244
util-print.h
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:1584
SigTableElmt_::alternative
uint16_t alternative
Definition: detect.h:1457
DetectAppLayerMpmRegister
void DetectAppLayerMpmRegister(const char *name, int direction, int priority, PrefilterRegisterFunc PrefilterRegister, InspectionBufferGetDataPtr GetData, AppProto alproto, int tx_min_progress)
register an app layer keyword for mpm
Definition: detect-engine-mpm.c:152
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:146
ALPROTO_HTTP2
@ ALPROTO_HTTP2
Definition: app-layer-protos.h:69
suricata-common.h
ALPROTO_HTTP1
@ ALPROTO_HTTP1
Definition: app-layer-protos.h:36
util-spm.h
detect-engine-buffer.h
InspectionBuffer::inspect
const uint8_t * inspect
Definition: detect-engine-inspect-buffer.h:35
str
#define str(s)
Definition: suricata-common.h:308
detect-parse.h
Signature_
Signature container.
Definition: detect.h:668
ALPROTO_HTTP
@ ALPROTO_HTTP
Definition: app-layer-protos.h:76
InspectionBufferSetupAndApplyTransforms
void InspectionBufferSetupAndApplyTransforms(DetectEngineThreadCtx *det_ctx, const int list_id, InspectionBuffer *buffer, const uint8_t *data, const uint32_t data_len, const DetectEngineTransforms *transforms)
setup the buffer with our initial data
Definition: detect-engine-inspect-buffer.c:197
SIGMATCH_NOOPT
#define SIGMATCH_NOOPT
Definition: detect.h:1651
DetectAppLayerInspectEngineRegister
void DetectAppLayerInspectEngineRegister(const char *name, AppProto alproto, uint32_t dir, int progress, InspectEngineFuncPtr Callback, InspectionBufferGetDataPtr GetData)
Registers an app inspection engine.
Definition: detect-engine.c:272
DETECT_HTTP_COOKIE
@ DETECT_HTTP_COOKIE
Definition: detect-engine-register.h:151
DetectBufferTypeSetDescriptionByName
void DetectBufferTypeSetDescriptionByName(const char *name, const char *desc)
Definition: detect-engine.c:1374
flow.h
flow-var.h
SigTableElmt_::RegisterTests
void(* RegisterTests)(void)
Definition: detect.h:1448
app-layer.h