--- /dev/null
+/* Copyright (C) 2007-2017 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.
+ */
+
+/**
+ * Stub for per HTTP header detection keyword. Meant to be included into
+ * a C file.
+ */
+
+/**
+ * \ingroup httplayer
+ *
+ * @{
+ */
+
+#include "suricata-common.h"
+#include "threads.h"
+#include "decode.h"
+#include "flow.h"
+#include "app-layer.h"
+#include "app-layer-parser.h"
+#include "app-layer-htp.h"
+
+#include "detect.h"
+#include "detect-parse.h"
+#include "detect-engine.h"
+#include "detect-engine-mpm.h"
+#include "detect-engine-state.h"
+#include "detect-engine-prefilter.h"
+#include "detect-engine-content-inspection.h"
+#include "detect-content.h"
+#include "detect-http-header.h"
+
+#include "util-debug.h"
+
+static int g_buffer_id = 0;
+
+#ifdef KEYWORD_TOSERVER
+/** \brief HTTP Headers Mpm prefilter callback
+ *
+ * \param det_ctx detection engine thread ctx
+ * \param p packet to inspect
+ * \param f flow to inspect
+ * \param txv tx to inspect
+ * \param pectx inspection context
+ */
+static void PrefilterTxHttpRequestHeader(DetectEngineThreadCtx *det_ctx,
+ const void *pectx,
+ Packet *p, Flow *f, void *txv,
+ const uint64_t idx, const uint8_t flags)
+{
+ SCEnter();
+ const MpmCtx *mpm_ctx = (MpmCtx *)pectx;
+ htp_tx_t *tx = (htp_tx_t *)txv;
+
+ if (tx->request_headers == NULL)
+ return;
+
+ htp_header_t *h = (htp_header_t *)htp_table_get_c(tx->request_headers,
+ HEADER_NAME);
+ if (h == NULL || h->value == NULL) {
+ SCLogDebug("HTTP %s header not present in this request", HEADER_NAME);
+ return;
+ }
+
+ const uint32_t buffer_len = bstr_len(h->value);
+ const uint8_t *buffer = bstr_ptr(h->value);
+
+ if (buffer_len >= mpm_ctx->minlen) {
+ (void)mpm_table[mpm_ctx->mpm_type].Search(mpm_ctx,
+ &det_ctx->mtcu, &det_ctx->pmq, buffer, buffer_len);
+ }
+}
+#if 0
+static void PrefilterTxHttpRequestTrailers(DetectEngineThreadCtx *det_ctx,
+ const void *pectx,
+ Packet *p, Flow *f, void *txv,
+ const uint64_t idx, const uint8_t flags)
+{
+ SCEnter();
+
+ const MpmCtx *mpm_ctx = (MpmCtx *)pectx;
+ htp_tx_t *tx = (htp_tx_t *)txv;
+
+ if (tx->request_headers == NULL)
+ return;
+ const HtpTxUserData *htud = (const HtpTxUserData *)htp_tx_get_user_data(tx);
+ /* if the request wasn't flagged as having a trailer, we skip */
+ if (htud && !htud->request_has_trailers)
+ return;
+
+ HtpState *htp_state = f->alstate;
+ uint32_t buffer_len = 0;
+ const uint8_t *buffer = DetectEngineHHDGetBufferForTX(tx, idx,
+ NULL, det_ctx,
+ f, htp_state,
+ flags,
+ &buffer_len);
+
+ if (buffer_len >= mpm_ctx->minlen) {
+ (void)mpm_table[mpm_ctx->mpm_type].Search(mpm_ctx,
+ &det_ctx->mtcu, &det_ctx->pmq, buffer, buffer_len);
+ }
+}
+#endif
+static int PrefilterTxHttpRequestHeaderRegister(SigGroupHead *sgh, MpmCtx *mpm_ctx)
+{
+ SCEnter();
+
+ int r = PrefilterAppendTxEngine(sgh, PrefilterTxHttpRequestHeader,
+ ALPROTO_HTTP, HTP_REQUEST_HEADERS,
+ mpm_ctx, NULL, KEYWORD_NAME " (request)");
+ return r;
+#if 0
+ if (r != 0)
+ return r;
+ return PrefilterAppendTxEngine(sgh, PrefilterTxHttpRequestTrailers,
+ ALPROTO_HTTP, HTP_REQUEST_TRAILER,
+ mpm_ctx, NULL, "http_header (request)");
+#endif
+}
+#endif
+
+#ifdef KEYWORD_TOCLIENT
+/** \brief HTTP Headers Mpm prefilter callback
+ *
+ * \param det_ctx detection engine thread ctx
+ * \param p packet to inspect
+ * \param f flow to inspect
+ * \param txv tx to inspect
+ * \param pectx inspection context
+ */
+static void PrefilterTxHttpResponseHeader(DetectEngineThreadCtx *det_ctx,
+ const void *pectx,
+ Packet *p, Flow *f, void *txv,
+ const uint64_t idx, const uint8_t flags)
+{
+ SCEnter();
+ const MpmCtx *mpm_ctx = (MpmCtx *)pectx;
+ htp_tx_t *tx = (htp_tx_t *)txv;
+
+ if (tx->response_headers == NULL)
+ return;
+
+ htp_header_t *h = (htp_header_t *)htp_table_get_c(tx->response_headers,
+ HEADER_NAME);
+ if (h == NULL || h->value == NULL) {
+ SCLogDebug("HTTP %s header not present in this request", HEADER_NAME);
+ return;
+ }
+
+ const uint32_t buffer_len = bstr_len(h->value);
+ const uint8_t *buffer = bstr_ptr(h->value);
+
+ if (buffer_len >= mpm_ctx->minlen) {
+ (void)mpm_table[mpm_ctx->mpm_type].Search(mpm_ctx,
+ &det_ctx->mtcu, &det_ctx->pmq, buffer, buffer_len);
+ }
+}
+#if 0
+static void PrefilterTxHttpResponseTrailers(DetectEngineThreadCtx *det_ctx,
+ const void *pectx,
+ Packet *p, Flow *f, void *txv,
+ const uint64_t idx, const uint8_t flags)
+{
+ SCEnter();
+
+ const MpmCtx *mpm_ctx = (MpmCtx *)pectx;
+ htp_tx_t *tx = (htp_tx_t *)txv;
+
+ if (tx->response_headers == NULL)
+ return;
+ const HtpTxUserData *htud = (const HtpTxUserData *)htp_tx_get_user_data(tx);
+ /* if the request wasn't flagged as having a trailer, we skip */
+ if (htud && !htud->response_has_trailers)
+ return;
+
+ HtpState *htp_state = f->alstate;
+ uint32_t buffer_len = 0;
+ const uint8_t *buffer = DetectEngineHHDGetBufferForTX(tx, idx,
+ NULL, det_ctx,
+ f, htp_state,
+ flags,
+ &buffer_len);
+
+ if (buffer_len >= mpm_ctx->minlen) {
+ (void)mpm_table[mpm_ctx->mpm_type].Search(mpm_ctx,
+ &det_ctx->mtcu, &det_ctx->pmq, buffer, buffer_len);
+ }
+}
+#endif
+static int PrefilterTxHttpResponseHeaderRegister(SigGroupHead *sgh, MpmCtx *mpm_ctx)
+{
+ SCEnter();
+
+ int r = PrefilterAppendTxEngine(sgh, PrefilterTxHttpResponseHeader,
+ ALPROTO_HTTP, HTP_RESPONSE_HEADERS,
+ mpm_ctx, NULL, KEYWORD_NAME " (response)");
+ return r;
+#if 0
+ if (r != 0)
+ return r;
+ return PrefilterAppendTxEngine(sgh, PrefilterTxHttpRequestTrailers,
+ ALPROTO_HTTP, HTP_REQUEST_TRAILER,
+ mpm_ctx, NULL, "http_header (request)");
+#endif
+}
+#endif
+
+#ifdef KEYWORD_TOSERVER
+static int InspectEngineHttpRequestHeader(ThreadVars *tv,
+ DetectEngineCtx *de_ctx, DetectEngineThreadCtx *det_ctx,
+ const Signature *s, const SigMatchData *smd,
+ Flow *f, uint8_t flags, void *alstate, void *txv, uint64_t tx_id)
+{
+ htp_tx_t *tx = (htp_tx_t *)txv;
+ if (tx->request_headers == NULL)
+ goto end;
+
+ htp_header_t *h = (htp_header_t *)htp_table_get_c(tx->request_headers,
+ HEADER_NAME);
+ if (h == NULL || h->value == NULL) {
+ SCLogDebug("HTTP UA header not present in this request");
+ goto end;
+ }
+
+ const uint32_t buffer_len = bstr_len(h->value);
+ uint8_t *buffer = bstr_ptr(h->value);
+
+ if (buffer_len == 0)
+ goto end;
+
+ det_ctx->buffer_offset = 0;
+ det_ctx->discontinue_matching = 0;
+ det_ctx->inspection_recursion_counter = 0;
+ int r = DetectEngineContentInspection(de_ctx, det_ctx, s, smd,
+ f,
+ buffer, buffer_len,
+ 0,
+ DETECT_ENGINE_CONTENT_INSPECTION_MODE_STATE, NULL);
+ if (r == 1)
+ return DETECT_ENGINE_INSPECT_SIG_MATCH;
+
+ end:
+ if (AppLayerParserGetStateProgress(IPPROTO_TCP, ALPROTO_HTTP, tx, flags) > HTP_REQUEST_HEADERS)
+ return DETECT_ENGINE_INSPECT_SIG_CANT_MATCH;
+ else
+ return DETECT_ENGINE_INSPECT_SIG_NO_MATCH;
+}
+#endif
+#ifdef KEYWORD_TOCLIENT
+static int InspectEngineHttpResponseHeader(ThreadVars *tv,
+ DetectEngineCtx *de_ctx, DetectEngineThreadCtx *det_ctx,
+ const Signature *s, const SigMatchData *smd,
+ Flow *f, uint8_t flags, void *alstate, void *txv, uint64_t tx_id)
+{
+ htp_tx_t *tx = (htp_tx_t *)txv;
+ if (tx->response_headers == NULL)
+ goto end;
+
+ htp_header_t *h = (htp_header_t *)htp_table_get_c(tx->response_headers,
+ HEADER_NAME);
+ if (h == NULL || h->value == NULL) {
+ SCLogDebug("HTTP header not present in this request");
+ goto end;
+ }
+
+ const uint32_t buffer_len = bstr_len(h->value);
+ uint8_t *buffer = bstr_ptr(h->value);
+
+ if (buffer_len == 0)
+ goto end;
+
+ det_ctx->buffer_offset = 0;
+ det_ctx->discontinue_matching = 0;
+ det_ctx->inspection_recursion_counter = 0;
+ int r = DetectEngineContentInspection(de_ctx, det_ctx, s, smd,
+ f,
+ buffer, buffer_len,
+ 0,
+ DETECT_ENGINE_CONTENT_INSPECTION_MODE_STATE, NULL);
+ if (r == 1)
+ return DETECT_ENGINE_INSPECT_SIG_MATCH;
+
+ end:
+ if (AppLayerParserGetStateProgress(IPPROTO_TCP, ALPROTO_HTTP, tx, flags) > HTP_RESPONSE_HEADERS)
+ return DETECT_ENGINE_INSPECT_SIG_CANT_MATCH;
+ else
+ return DETECT_ENGINE_INSPECT_SIG_NO_MATCH;
+}
+#endif
+
+/**
+ * \brief The setup function for the http_header keyword for a signature.
+ *
+ * \param de_ctx Pointer to the detection engine context.
+ * \param s Pointer to signature for the current Signature being parsed
+ * from the rules.
+ * \param m Pointer to the head of the SigMatchs for the current rule
+ * being parsed.
+ * \param arg Pointer to the string holding the keyword value.
+ *
+ * \retval 0 On success.
+ * \retval -1 On failure.
+ */
+static int DetectHttpHeadersSetup(DetectEngineCtx *de_ctx, Signature *s, char *arg)
+{
+ s->init_data->list = g_buffer_id;
+ return 0;
+}
+
+static void DetectHttpHeadersSetupCallback(Signature *s)
+{
+ SCLogDebug("callback invoked by %u", s->id);
+ s->mask |= SIG_MASK_REQUIRE_HTTP_STATE;
+}
+
+static void DetectHttpHeadersRegisterStub(void)
+{
+ sigmatch_table[KEYWORD_ID].name = KEYWORD_NAME;
+ sigmatch_table[KEYWORD_ID].desc = KEYWORD_NAME " sticky buffer for the " BUFFER_DESC;
+ sigmatch_table[KEYWORD_ID].url = DOC_URL DOC_VERSION "/" KEYWORD_DOC;
+ sigmatch_table[KEYWORD_ID].Setup = DetectHttpHeadersSetup;
+ sigmatch_table[KEYWORD_ID].flags |= SIGMATCH_NOOPT;
+#ifdef KEYWORD_TOSERVER
+ DetectAppLayerMpmRegister(BUFFER_NAME, SIG_FLAG_TOSERVER, 2,
+ PrefilterTxHttpRequestHeaderRegister);
+#endif
+#ifdef KEYWORD_TOCLIENT
+ DetectAppLayerMpmRegister(BUFFER_NAME, SIG_FLAG_TOCLIENT, 2,
+ PrefilterTxHttpResponseHeaderRegister);
+#endif
+#ifdef KEYWORD_TOSERVER
+ DetectAppLayerInspectEngineRegister(BUFFER_NAME,
+ ALPROTO_HTTP, SIG_FLAG_TOSERVER,
+ InspectEngineHttpRequestHeader);
+#endif
+#ifdef KEYWORD_TOCLIENT
+ DetectAppLayerInspectEngineRegister(BUFFER_NAME,
+ ALPROTO_HTTP, SIG_FLAG_TOCLIENT,
+ InspectEngineHttpResponseHeader);
+#endif
+
+ DetectBufferTypeSetDescriptionByName(BUFFER_NAME, BUFFER_DESC);
+
+ DetectBufferTypeRegisterSetupCallback(BUFFER_NAME,
+ DetectHttpHeadersSetupCallback);
+
+ g_buffer_id = DetectBufferTypeGetByName(BUFFER_NAME);
+}
projects / thirdparty / suricata.git / commitdiff
