diff options
Diffstat (limited to 'framework/src/suricata/src/detect-fragoffset.c')
| -rw-r--r-- | framework/src/suricata/src/detect-fragoffset.c | 396 |
1 files changed, 0 insertions, 396 deletions
diff --git a/framework/src/suricata/src/detect-fragoffset.c b/framework/src/suricata/src/detect-fragoffset.c deleted file mode 100644 index c887b7b9..00000000 --- a/framework/src/suricata/src/detect-fragoffset.c +++ /dev/null @@ -1,396 +0,0 @@ -/* Copyright (C) 2007-2010 Open Information Security Foundation - * - * You can copy, redistribute or modify this Program under the terms of - * the GNU General Public License version 2 as published by the Free - * Software Foundation. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - * You should have received a copy of the GNU General Public License - * version 2 along with this program; if not, write to the Free Software - * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA - * 02110-1301, USA. - */ - -/** - * \file - * - * \author Breno Silva <breno.silva@gmail.com> - * - * Implements fragoffset keyword - */ - -#include "suricata-common.h" -#include "debug.h" -#include "decode.h" -#include "decode-ipv4.h" -#include "decode-ipv6.h" - -#include "detect.h" -#include "detect-parse.h" - -#include "detect-fragoffset.h" - -#include "util-byte.h" -#include "util-unittest.h" -#include "util-debug.h" - -#define PARSE_REGEX "^\\s*(?:(<|>))?\\s*([0-9]+)" - -static pcre *parse_regex; -static pcre_extra *parse_regex_study; - -int DetectFragOffsetMatch(ThreadVars *, DetectEngineThreadCtx *, Packet *, Signature *, const SigMatchCtx *); -static int DetectFragOffsetSetup(DetectEngineCtx *, Signature *, char *); -void DetectFragOffsetRegisterTests(void); -void DetectFragOffsetFree(void *); - -/** - * \brief Registration function for fragoffset - */ -void DetectFragOffsetRegister (void) -{ - sigmatch_table[DETECT_FRAGOFFSET].name = "fragoffset"; - sigmatch_table[DETECT_FRAGOFFSET].desc = "match on specific decimal values of the IP fragment offset field"; - sigmatch_table[DETECT_FRAGOFFSET].url = "https://redmine.openinfosecfoundation.org/projects/suricata/wiki/Header_keywords#Fragoffset"; - sigmatch_table[DETECT_FRAGOFFSET].Match = DetectFragOffsetMatch; - sigmatch_table[DETECT_FRAGOFFSET].Setup = DetectFragOffsetSetup; - sigmatch_table[DETECT_FRAGOFFSET].Free = DetectFragOffsetFree; - sigmatch_table[DETECT_FRAGOFFSET].RegisterTests = DetectFragOffsetRegisterTests; - - const char *eb; - int eo; - int opts = 0; - - parse_regex = pcre_compile(PARSE_REGEX, opts, &eb, &eo, NULL); - if (parse_regex == NULL) { - SCLogError(SC_ERR_PCRE_COMPILE,"pcre compile of \"%s\" failed at offset %" PRId32 ": %s", PARSE_REGEX, eo, eb); - goto error; - } - - parse_regex_study = pcre_study(parse_regex, 0, &eb); - if (eb != NULL) { - SCLogError(SC_ERR_PCRE_STUDY,"pcre study failed: %s", eb); - goto error; - } - return; - -error: - return; -} - -/** - * \brief This function is used to match fragoffset rule option set on a packet - * - * \param t pointer to thread vars - * \param det_ctx pointer to the pattern matcher thread - * \param p pointer to the current packet - * \param m pointer to the sigmatch that we will cast into DetectFragOffsetData - * - * \retval 0 no match or frag is not set - * \retval 1 match - * - */ -int DetectFragOffsetMatch (ThreadVars *t, DetectEngineThreadCtx *det_ctx, Packet *p, Signature *s, const SigMatchCtx *ctx) -{ - uint16_t frag = 0; - const DetectFragOffsetData *fragoff = (const DetectFragOffsetData *)ctx; - - if (PKT_IS_PSEUDOPKT(p)) - return 0; - - if (PKT_IS_IPV4(p)) { - frag = IPV4_GET_IPOFFSET(p); - } else if (PKT_IS_IPV6(p)) { - if(IPV6_EXTHDR_FH(p)) { - frag = IPV6_EXTHDR_GET_FH_OFFSET(p); - } else { - return 0; - } - } else { - SCLogDebug("No IPv4 or IPv6 packet"); - return 0; - } - - switch (fragoff->mode) { - case FRAG_LESS: - if (frag < fragoff->frag_off) return 1; - break; - case FRAG_MORE: - if (frag > fragoff->frag_off) return 1; - break; - default: - if (frag == fragoff->frag_off) return 1; - } - - return 0; -} - -/** - * \brief This function is used to parse fragoffset option passed via fragoffset: keyword - * - * \param fragoffsetstr Pointer to the user provided fragoffset options - * - * \retval fragoff pointer to DetectFragOffsetData on success - * \retval NULL on failure - */ -DetectFragOffsetData *DetectFragOffsetParse (char *fragoffsetstr) -{ - DetectFragOffsetData *fragoff = NULL; - char *substr[3] = {NULL, NULL, NULL}; -#define MAX_SUBSTRINGS 30 - int ret = 0, res = 0; - int ov[MAX_SUBSTRINGS]; - int i; - const char *str_ptr; - char *mode = NULL; - - ret = pcre_exec(parse_regex, parse_regex_study, fragoffsetstr, strlen(fragoffsetstr), 0, 0, ov, MAX_SUBSTRINGS); - if (ret < 1 || ret > 4) { - SCLogError(SC_ERR_PCRE_MATCH,"Parse error %s", fragoffsetstr); - goto error; - } - - for (i = 1; i < ret; i++) { - res = pcre_get_substring((char *)fragoffsetstr, ov, MAX_SUBSTRINGS, i, &str_ptr); - if (res < 0) { - SCLogError(SC_ERR_PCRE_GET_SUBSTRING,"pcre_get_substring failed"); - goto error; - } - substr[i-1] = (char *)str_ptr; - } - - fragoff = SCMalloc(sizeof(DetectFragOffsetData)); - if (unlikely(fragoff == NULL)) - goto error; - - fragoff->frag_off = 0; - fragoff->mode = 0; - - mode = substr[0]; - - if(mode != NULL) { - - while(*mode != '\0') { - switch(*mode) { - case '>': - fragoff->mode = FRAG_MORE; - break; - case '<': - fragoff->mode = FRAG_LESS; - break; - } - mode++; - } - } - - if (ByteExtractStringUint16(&fragoff->frag_off, 10, 0, substr[1]) < 0) { - SCLogError(SC_ERR_INVALID_ARGUMENT, "specified frag offset %s is not " - "valid", substr[1]); - goto error; - } - - for (i = 0; i < 3; i++) { - if (substr[i] != NULL) SCFree(substr[i]); - } - - return fragoff; - -error: - for (i = 0; i < 3; i++) { - if (substr[i] != NULL) SCFree(substr[i]); - } - if (fragoff != NULL) DetectFragOffsetFree(fragoff); - return NULL; - -} - -/** - * \brief this function is used to add the parsed fragoffset data into the current signature - * - * \param de_ctx pointer to the Detection Engine Context - * \param s pointer to the Current Signature - * \param fragoffsetstr pointer to the user provided fragoffset option - * - * \retval 0 on Success - * \retval -1 on Failure - */ -static int DetectFragOffsetSetup (DetectEngineCtx *de_ctx, Signature *s, char *fragoffsetstr) -{ - DetectFragOffsetData *fragoff = NULL; - SigMatch *sm = NULL; - - fragoff = DetectFragOffsetParse(fragoffsetstr); - if (fragoff == NULL) goto error; - - sm = SigMatchAlloc(); - if (sm == NULL) goto error; - - sm->type = DETECT_FRAGOFFSET; - sm->ctx = (SigMatchCtx *)fragoff; - - SigMatchAppendSMToList(s, sm, DETECT_SM_LIST_MATCH); - s->flags |= SIG_FLAG_REQUIRE_PACKET; - - return 0; - -error: - if (fragoff != NULL) DetectFragOffsetFree(fragoff); - if (sm != NULL) SCFree(sm); - return -1; - -} - -/** - * \brief this function will free memory associated with DetectFragOffsetData - * - * \param ptr pointer to DetectFragOffsetData - */ -void DetectFragOffsetFree (void *ptr) -{ - DetectFragOffsetData *fragoff = (DetectFragOffsetData *)ptr; - SCFree(fragoff); -} - -#ifdef UNITTESTS - -#include "detect-parse.h" -#include "detect-engine.h" -#include "detect-engine-mpm.h" - -/** - * \test DetectFragOffsetParseTest01 is a test for setting a valid fragoffset value - */ -int DetectFragOffsetParseTest01 (void) -{ - DetectFragOffsetData *fragoff = NULL; - fragoff = DetectFragOffsetParse("300"); - if (fragoff != NULL && fragoff->frag_off == 300) { - DetectFragOffsetFree(fragoff); - return 1; - } - return 0; -} - -/** - * \test DetectFragOffsetParseTest02 is a test for setting a valid fragoffset value - * with spaces all around - */ -int DetectFragOffsetParseTest02 (void) -{ - DetectFragOffsetData *fragoff = NULL; - fragoff = DetectFragOffsetParse(">300"); - if (fragoff != NULL && fragoff->frag_off == 300 && fragoff->mode == FRAG_MORE) { - DetectFragOffsetFree(fragoff); - return 1; - } - return 0; -} - -/** - * \test DetectFragOffsetParseTest03 is a test for setting an invalid fragoffset value - */ -int DetectFragOffsetParseTest03 (void) -{ - DetectFragOffsetData *fragoff = NULL; - fragoff = DetectFragOffsetParse("badc"); - if (fragoff != NULL) { - DetectFragOffsetFree(fragoff); - return 1; - } - return 0; -} - -/** - * \test DetectFragOffsetMatchTest01 is a test for checking the working of - * fragoffset keyword by creating 2 rules and matching a crafted packet - * against them. Only the first one shall trigger. - */ -int DetectFragOffsetMatchTest01 (void) -{ - int result = 0; - Packet *p = SCMalloc(SIZE_OF_PACKET); - if (unlikely(p == NULL)) - return 0; - Signature *s = NULL; - DecodeThreadVars dtv; - ThreadVars th_v; - DetectEngineThreadCtx *det_ctx = NULL; - IPV4Hdr ip4h; - - memset(p, 0, SIZE_OF_PACKET); - memset(&ip4h, 0, sizeof(IPV4Hdr)); - memset(&dtv, 0, sizeof(DecodeThreadVars)); - memset(&th_v, 0, sizeof(ThreadVars)); - - FlowInitConfig(FLOW_QUIET); - - p->src.family = AF_INET; - p->dst.family = AF_INET; - p->src.addr_data32[0] = 0x01020304; - p->dst.addr_data32[0] = 0x04030201; - - ip4h.s_ip_src.s_addr = p->src.addr_data32[0]; - ip4h.s_ip_dst.s_addr = p->dst.addr_data32[0]; - ip4h.ip_off = 0x2222; - p->ip4h = &ip4h; - - DetectEngineCtx *de_ctx = DetectEngineCtxInit(); - if (de_ctx == NULL) { - goto end; - } - - de_ctx->flags |= DE_QUIET; - - s = de_ctx->sig_list = SigInit(de_ctx, "alert ip any any -> any any (fragoffset:546; sid:1;)"); - if (s == NULL) { - goto end; - } - - s = s->next = SigInit(de_ctx, "alert ip any any -> any any (fragoffset:5000; sid:2;)"); - if (s == NULL) { - goto end; - } - - SigGroupBuild(de_ctx); - DetectEngineThreadCtxInit(&th_v, (void *)de_ctx, (void *)&det_ctx); - - SigMatchSignatures(&th_v, de_ctx, det_ctx, p); - if (PacketAlertCheck(p, 1) == 0) { - printf("sid 1 did not alert, but should have: "); - goto cleanup; - } else if (PacketAlertCheck(p, 2)) { - printf("sid 2 alerted, but should not have: "); - goto cleanup; - } - - result = 1; - -cleanup: - SigGroupCleanup(de_ctx); - SigCleanSignatures(de_ctx); - - DetectEngineThreadCtxDeinit(&th_v, (void *)det_ctx); - DetectEngineCtxFree(de_ctx); - - FlowShutdown(); -end: - SCFree(p); - return result; - -} -#endif /* UNITTESTS */ - -void DetectFragOffsetRegisterTests (void) -{ -#ifdef UNITTESTS - UtRegisterTest("DetectFragOffsetParseTest01", DetectFragOffsetParseTest01, 1); - UtRegisterTest("DetectFragOffsetParseTest02", DetectFragOffsetParseTest02, 1); - UtRegisterTest("DetectFragOffsetParseTest03", DetectFragOffsetParseTest03, 0); - UtRegisterTest("DetectFragOffsetMatchTest01", DetectFragOffsetMatchTest01, 1); -#endif /* UNITTESTS */ -} - |