suricata
detect-filesha256.c
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1 /* Copyright (C) 2007-2016 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 Duarte Silva <duarte.silva@serializing.me>
23  *
24  */
25 
26 #include "suricata-common.h"
27 
28 #include "detect-engine.h"
30 #include "util-unittest.h"
31 #include "util-unittest-helper.h"
32 
33 #include "detect-filesha256.h"
34 
35 #ifndef HAVE_NSS
36 
37 static int DetectFileSha256SetupNoSupport (DetectEngineCtx *a, Signature *b, const char *c)
38 {
39  SCLogError(SC_ERR_NO_SHA256_SUPPORT, "no SHA-256 calculation support built in, needed for filesha256 keyword");
40  return -1;
41 }
42 
43 /**
44  * \brief Registration function for keyword: filesha256
45  */
47 {
48  sigmatch_table[DETECT_FILESHA256].name = "filesha256";
50  sigmatch_table[DETECT_FILESHA256].Setup = DetectFileSha256SetupNoSupport;
54 
55  SCLogDebug("registering filesha256 rule option");
56  return;
57 }
58 
59 #else /* HAVE_NSS */
60 
61 static int DetectFileSha256Setup (DetectEngineCtx *, Signature *, const char *);
62 static void DetectFileSha256RegisterTests(void);
63 static int g_file_match_list_id = 0;
64 
65 /**
66  * \brief Registration function for keyword: filesha256
67  */
68 void DetectFileSha256Register(void)
69 {
70  sigmatch_table[DETECT_FILESHA256].name = "filesha256";
71  sigmatch_table[DETECT_FILESHA256].desc = "match file SHA-256 against list of SHA-256 checksums";
72  sigmatch_table[DETECT_FILESHA256].url = DOC_URL DOC_VERSION "/rules/file-keywords.html#filesha256";
74  sigmatch_table[DETECT_FILESHA256].Setup = DetectFileSha256Setup;
76  sigmatch_table[DETECT_FILESHA256].RegisterTests = DetectFileSha256RegisterTests;
77 
78  g_file_match_list_id = DetectBufferTypeRegister("files");
79 
80  SCLogDebug("registering filesha256 rule option");
81  return;
82 }
83 
84 /**
85  * \brief this function is used to parse filesha256 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 "filesha256" option
91  *
92  * \retval 0 on Success
93  * \retval -1 on Failure
94  */
95 static int DetectFileSha256Setup (DetectEngineCtx *de_ctx, Signature *s, const char *str)
96 {
97  return DetectFileHashSetup(de_ctx, s, str, DETECT_FILESHA256, g_file_match_list_id);
98 }
99 
100 #ifdef UNITTESTS
101 static int SHA256MatchLookupString(ROHashTable *hash, const char *string)
102 {
103  uint8_t sha256[32];
104  if (ReadHashString(sha256, string, "file", 88, 64) == 1) {
105  void *ptr = ROHashLookup(hash, &sha256, (uint16_t)sizeof(sha256));
106  if (ptr == NULL)
107  return 0;
108  else
109  return 1;
110  }
111  return 0;
112 }
113 
114 static int SHA256MatchTest01(void)
115 {
116  ROHashTable *hash = ROHashInit(4, 32);
117  if (hash == NULL) {
118  return 0;
119  }
120  if (LoadHashTable(hash, "9c891edb5da763398969b6aaa86a5d46971bd28a455b20c2067cb512c9f9a0f8", "file", 1, DETECT_FILESHA256) != 1)
121  return 0;
122  if (LoadHashTable(hash, "6eee51705f34b6cfc7f0c872a7949ec3e3172a908303baf5d67d03b98f70e7e3", "file", 2, DETECT_FILESHA256) != 1)
123  return 0;
124  if (LoadHashTable(hash, "b12c7d57507286bbbe36d7acf9b34c22c96606ffd904e3c23008399a4a50c047", "file", 3, DETECT_FILESHA256) != 1)
125  return 0;
126  if (LoadHashTable(hash, "ca496e1ddadc290050339dd75ce8830ad3028ce1556a5368874a4aec3aee114b", "file", 4, DETECT_FILESHA256) != 1)
127  return 0;
128  if (LoadHashTable(hash, "275a021bbfb6489e54d471899f7db9d1663fc695ec2fe2a2c4538aabf651fd0f", "file", 5, DETECT_FILESHA256) != 1)
129  return 0;
130  if (LoadHashTable(hash, "d765e722e295969c0a5c2d90f549db8b89ab617900bf4698db41c7cdad993bb9", "file", 6, DETECT_FILESHA256) != 1)
131  return 0;
132 
133  if (ROHashInitFinalize(hash) != 1) {
134  return 0;
135  }
136 
137  if (SHA256MatchLookupString(hash, "9c891edb5da763398969b6aaa86a5d46971bd28a455b20c2067cb512c9f9a0f8") != 1)
138  return 0;
139  if (SHA256MatchLookupString(hash, "6eee51705f34b6cfc7f0c872a7949ec3e3172a908303baf5d67d03b98f70e7e3") != 1)
140  return 0;
141  if (SHA256MatchLookupString(hash, "b12c7d57507286bbbe36d7acf9b34c22c96606ffd904e3c23008399a4a50c047") != 1)
142  return 0;
143  if (SHA256MatchLookupString(hash, "ca496e1ddadc290050339dd75ce8830ad3028ce1556a5368874a4aec3aee114b") != 1)
144  return 0;
145  if (SHA256MatchLookupString(hash, "275a021bbfb6489e54d471899f7db9d1663fc695ec2fe2a2c4538aabf651fd0f") != 1)
146  return 0;
147  if (SHA256MatchLookupString(hash, "d765e722e295969c0a5c2d90f549db8b89ab617900bf4698db41c7cdad993bb9") != 1)
148  return 0;
149  /* Shouldn't match */
150  if (SHA256MatchLookupString(hash, "3333333333333333333333333333333333333333333333333333333333333333") == 1)
151  return 0;
152 
153  ROHashFree(hash);
154  return 1;
155 }
156 #endif
157 
158 void DetectFileSha256RegisterTests(void)
159 {
160 #ifdef UNITTESTS
161  UtRegisterTest("SHA256MatchTest01", SHA256MatchTest01);
162 #endif
163 }
164 
165 #endif /* HAVE_NSS */
SigTableElmt sigmatch_table[DETECT_TBLSIZE]
Definition: detect.h:1448
int(* Setup)(DetectEngineCtx *, Signature *, const char *)
Definition: detect.h:1186
#define SCLogDebug(...)
Definition: util-debug.h:335
int DetectFileHashMatch(DetectEngineThreadCtx *, Flow *, uint8_t, File *, const Signature *, const SigMatchCtx *)
void DetectFileHashFree(void *)
const char * name
Definition: detect.h:1200
Signature container.
Definition: detect.h:522
main detection engine ctx
Definition: detect.h:761
#define str(s)
void * ROHashLookup(ROHashTable *table, void *data, uint16_t size)
Definition: util-rohash.c:113
int(* FileMatch)(DetectEngineThreadCtx *, Flow *, uint8_t flags, File *, const Signature *, const SigMatchCtx *)
Definition: detect.h:1178
#define SIGMATCH_NOT_BUILT
Definition: detect.h:1375
void(* Free)(void *)
Definition: detect.h:1191
#define SCLogError(err_code,...)
Macro used to log ERROR messages.
Definition: util-debug.h:294
void DetectFileSha256Register(void)
Registration function for keyword: filesha256.
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:1202
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:1203
int DetectFileHashSetup(DetectEngineCtx *, Signature *, const char *, uint32_t, int)
#define DOC_URL
Definition: suricata.h:86
#define DOC_VERSION
Definition: suricata.h:91
uint16_t flags
Definition: detect.h:1194
void(* RegisterTests)(void)
Definition: detect.h:1192