suricata
detect-filemd5.c
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1 /* Copyright (C) 2007-2012 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  *
23  */
24 
25 #include "suricata-common.h"
26 
27 #include "detect-engine.h"
29 #include "util-unittest.h"
30 #include "util-unittest-helper.h"
31 
32 #include "detect-filemd5.h"
33 
34 #ifndef HAVE_NSS
35 
36 static int DetectFileMd5SetupNoSupport (DetectEngineCtx *a, Signature *b, const char *c)
37 {
38  SCLogError(SC_ERR_NO_MD5_SUPPORT, "no MD5 calculation support built in, needed for filemd5 keyword");
39  return -1;
40 }
41 
42 /**
43  * \brief Registration function for keyword: filemd5
44  */
46 {
47  sigmatch_table[DETECT_FILEMD5].name = "filemd5";
49  sigmatch_table[DETECT_FILEMD5].Setup = DetectFileMd5SetupNoSupport;
53 
54  SCLogDebug("registering filemd5 rule option");
55  return;
56 }
57 
58 #else /* HAVE_NSS */
59 
60 static int g_file_match_list_id = 0;
61 
62 static int DetectFileMd5Setup (DetectEngineCtx *, Signature *, const char *);
63 static void DetectFileMd5RegisterTests(void);
64 
65 /**
66  * \brief Registration function for keyword: filemd5
67  */
68 void DetectFileMd5Register(void)
69 {
70  sigmatch_table[DETECT_FILEMD5].name = "filemd5";
71  sigmatch_table[DETECT_FILEMD5].desc = "match file MD5 against list of MD5 checksums";
72  sigmatch_table[DETECT_FILEMD5].url = DOC_URL DOC_VERSION "/rules/file-keywords.html#filemd5";
74  sigmatch_table[DETECT_FILEMD5].Setup = DetectFileMd5Setup;
76  sigmatch_table[DETECT_FILEMD5].RegisterTests = DetectFileMd5RegisterTests;
77 
78  g_file_match_list_id = DetectBufferTypeRegister("files");
79 
80  SCLogDebug("registering filemd5 rule option");
81  return;
82 }
83 
84 /**
85  * \brief this function is used to parse filemd5 options
86  * \brief into the current signature
87  *
88  * \param de_ctx pointer to the Detection Engine Context
89  * \param s pointer to the Current Signature
90  * \param str pointer to the user provided "filemd5" option
91  *
92  * \retval 0 on Success
93  * \retval -1 on Failure
94  */
95 static int DetectFileMd5Setup (DetectEngineCtx *de_ctx, Signature *s, const char *str)
96 {
97  return DetectFileHashSetup(de_ctx, s, str, DETECT_FILEMD5, g_file_match_list_id);
98 }
99 
100 #ifdef UNITTESTS
101 static int MD5MatchLookupString(ROHashTable *hash, const char *string)
102 {
103  uint8_t md5[16];
104  if (ReadHashString(md5, string, "file", 88, 32) == 1) {
105  void *ptr = ROHashLookup(hash, &md5, (uint16_t)sizeof(md5));
106  if (ptr == NULL)
107  return 0;
108  else
109  return 1;
110  }
111  return 0;
112 }
113 
114 static int MD5MatchTest01(void)
115 {
116  ROHashTable *hash = ROHashInit(4, 16);
117  if (hash == NULL) {
118  return 0;
119  }
120  if (LoadHashTable(hash, "d80f93a93dc5f3ee945704754d6e0a36", "file", 1, DETECT_FILEMD5) != 1)
121  return 0;
122  if (LoadHashTable(hash, "92a49985b384f0d993a36e4c2d45e206", "file", 2, DETECT_FILEMD5) != 1)
123  return 0;
124  if (LoadHashTable(hash, "11adeaacc8c309815f7bc3e33888f281", "file", 3, DETECT_FILEMD5) != 1)
125  return 0;
126  if (LoadHashTable(hash, "22e10a8fe02344ade0bea8836a1714af", "file", 4, DETECT_FILEMD5) != 1)
127  return 0;
128  if (LoadHashTable(hash, "c3db2cbf02c68f073afcaee5634677bc", "file", 5, DETECT_FILEMD5) != 1)
129  return 0;
130  if (LoadHashTable(hash, "7ed095da259638f42402fb9e74287a17", "file", 6, DETECT_FILEMD5) != 1)
131  return 0;
132 
133  if (ROHashInitFinalize(hash) != 1) {
134  return 0;
135  }
136 
137  if (MD5MatchLookupString(hash, "d80f93a93dc5f3ee945704754d6e0a36") != 1)
138  return 0;
139  if (MD5MatchLookupString(hash, "92a49985b384f0d993a36e4c2d45e206") != 1)
140  return 0;
141  if (MD5MatchLookupString(hash, "11adeaacc8c309815f7bc3e33888f281") != 1)
142  return 0;
143  if (MD5MatchLookupString(hash, "22e10a8fe02344ade0bea8836a1714af") != 1)
144  return 0;
145  if (MD5MatchLookupString(hash, "c3db2cbf02c68f073afcaee5634677bc") != 1)
146  return 0;
147  if (MD5MatchLookupString(hash, "7ed095da259638f42402fb9e74287a17") != 1)
148  return 0;
149  /* shouldn't match */
150  if (MD5MatchLookupString(hash, "33333333333333333333333333333333") == 1)
151  return 0;
152 
153  ROHashFree(hash);
154  return 1;
155 }
156 #endif
157 
158 void DetectFileMd5RegisterTests(void)
159 {
160 #ifdef UNITTESTS
161  UtRegisterTest("MD5MatchTest01", MD5MatchTest01);
162 #endif
163 }
164 
165 #endif /* HAVE_NSS */
166 
void DetectFileMd5Register(void)
Registration function for keyword: filemd5.
SigTableElmt sigmatch_table[DETECT_TBLSIZE]
Definition: detect.h:1406
int(* Setup)(DetectEngineCtx *, Signature *, const char *)
Definition: detect.h:1149
#define SCLogDebug(...)
Definition: util-debug.h:335
void DetectFileHashFree(void *)
const char * name
Definition: detect.h:1163
Signature container.
Definition: detect.h:495
main detection engine ctx
Definition: detect.h:723
#define str(s)
void * ROHashLookup(ROHashTable *table, void *data, uint16_t size)
Definition: util-rohash.c:113
int(* FileMatch)(ThreadVars *, DetectEngineThreadCtx *, Flow *, uint8_t flags, File *, const Signature *, const SigMatchCtx *)
Definition: detect.h:1140
#define SIGMATCH_NOT_BUILT
Definition: detect.h:1337
void(* Free)(void *)
Definition: detect.h:1154
#define SCLogError(err_code,...)
Macro used to log ERROR messages.
Definition: util-debug.h:294
void UtRegisterTest(const char *name, int(*TestFn)(void))
Register unit test.
ROHashTable * ROHashInit(uint8_t hash_bits, uint16_t item_size)
initialize a new rohash
Definition: util-rohash.c:64
int ReadHashString(uint8_t *, const char *, const char *, int, uint16_t)
const char * desc
Definition: detect.h:1165
int DetectBufferTypeRegister(const char *name)
int ROHashInitFinalize(ROHashTable *table)
create final hash data structure
Definition: util-rohash.c:183
void ROHashFree(ROHashTable *table)
Definition: util-rohash.c:92
int LoadHashTable(ROHashTable *, const char *, const char *, int, uint32_t)
const char * url
Definition: detect.h:1166
int DetectFileHashSetup(DetectEngineCtx *, Signature *, const char *, uint32_t, int)
#define DOC_URL
Definition: suricata.h:86
int DetectFileHashMatch(ThreadVars *, DetectEngineThreadCtx *, Flow *, uint8_t, File *, const Signature *, const SigMatchCtx *)
#define DOC_VERSION
Definition: suricata.h:91
uint16_t flags
Definition: detect.h:1157
void(* RegisterTests)(void)
Definition: detect.h:1155