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diff --git a/src/detect-http-method.c b/src/detect-http-method.c
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+/* Copyright (C) 2007-2019 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.
+ */
+
+/**
+ * \ingroup httplayer
+ *
+ * @{
+ */
+
+
+/**
+ * \file
+ *
+ * \author Brian Rectanus <brectanu@gmail.com>
+ *
+ * Implements the http_method keyword
+ */
+
+#include "suricata-common.h"
+#include "threads.h"
+#include "decode.h"
+#include "detect.h"
+
+#include "detect-parse.h"
+#include "detect-engine.h"
+#include "detect-engine-mpm.h"
+#include "detect-engine-prefilter.h"
+#include "detect-content.h"
+#include "detect-pcre.h"
+
+#include "flow.h"
+#include "flow-var.h"
+#include "flow-util.h"
+
+#include "util-debug.h"
+#include "util-unittest.h"
+#include "util-unittest-helper.h"
+#include "util-spm.h"
+
+#include "app-layer.h"
+#include "app-layer-parser.h"
+
+#include "app-layer-htp.h"
+#include "detect-http-method.h"
+#include "stream-tcp.h"
+
+static int g_http_method_buffer_id = 0;
+static int DetectHttpMethodSetup(DetectEngineCtx *, Signature *, const char *);
+static int DetectHttpMethodSetupSticky(DetectEngineCtx *de_ctx, Signature *s, const char *str);
+#ifdef UNITTESTS
+void DetectHttpMethodRegisterTests(void);
+#endif
+void DetectHttpMethodFree(void *);
+static bool DetectHttpMethodValidateCallback(const Signature *s, const char **sigerror);
+static InspectionBuffer *GetData(DetectEngineThreadCtx *det_ctx,
+ const DetectEngineTransforms *transforms, Flow *_f,
+ const uint8_t _flow_flags, void *txv, const int list_id);
+static InspectionBuffer *GetData2(DetectEngineThreadCtx *det_ctx,
+ const DetectEngineTransforms *transforms, Flow *_f, const uint8_t _flow_flags, void *txv,
+ const int list_id);
+
+/**
+ * \brief Registration function for keyword: http_method
+ */
+void DetectHttpMethodRegister(void)
+{
+ /* http_method content modifier */
+ sigmatch_table[DETECT_AL_HTTP_METHOD].name = "http_method";
+ sigmatch_table[DETECT_AL_HTTP_METHOD].desc = "content modifier to match only on the HTTP method-buffer";
+ sigmatch_table[DETECT_AL_HTTP_METHOD].url = "/rules/http-keywords.html#http-method";
+ sigmatch_table[DETECT_AL_HTTP_METHOD].Match = NULL;
+ sigmatch_table[DETECT_AL_HTTP_METHOD].Setup = DetectHttpMethodSetup;
+#ifdef UNITTESTS
+ sigmatch_table[DETECT_AL_HTTP_METHOD].RegisterTests = DetectHttpMethodRegisterTests;
+#endif
+ sigmatch_table[DETECT_AL_HTTP_METHOD].flags |= SIGMATCH_NOOPT|SIGMATCH_INFO_CONTENT_MODIFIER;
+ sigmatch_table[DETECT_AL_HTTP_METHOD].alternative = DETECT_HTTP_METHOD;
+
+ /* http.method sticky buffer */
+ sigmatch_table[DETECT_HTTP_METHOD].name = "http.method";
+ sigmatch_table[DETECT_HTTP_METHOD].desc = "sticky buffer to match specifically and only on the HTTP method buffer";
+ sigmatch_table[DETECT_HTTP_METHOD].url = "/rules/http-keywords.html#http-method";
+ sigmatch_table[DETECT_HTTP_METHOD].Setup = DetectHttpMethodSetupSticky;
+ sigmatch_table[DETECT_HTTP_METHOD].flags |= SIGMATCH_NOOPT|SIGMATCH_INFO_STICKY_BUFFER;
+
+ DetectAppLayerInspectEngineRegister2("http_method", ALPROTO_HTTP1, SIG_FLAG_TOSERVER,
+ HTP_REQUEST_LINE, DetectEngineInspectBufferGeneric, GetData);
+
+ DetectAppLayerMpmRegister2("http_method", SIG_FLAG_TOSERVER, 4, PrefilterGenericMpmRegister,
+ GetData, ALPROTO_HTTP1, HTP_REQUEST_LINE);
+
+ DetectAppLayerInspectEngineRegister2("http_method", ALPROTO_HTTP2, SIG_FLAG_TOSERVER,
+ HTTP2StateDataClient, DetectEngineInspectBufferGeneric, GetData2);
+
+ DetectAppLayerMpmRegister2("http_method", SIG_FLAG_TOSERVER, 4, PrefilterGenericMpmRegister,
+ GetData2, ALPROTO_HTTP2, HTTP2StateDataClient);
+
+ DetectBufferTypeSetDescriptionByName("http_method",
+ "http request method");
+
+ DetectBufferTypeRegisterValidateCallback("http_method",
+ DetectHttpMethodValidateCallback);
+
+ g_http_method_buffer_id = DetectBufferTypeGetByName("http_method");
+
+ SCLogDebug("registering http_method rule option");
+}
+
+/**
+ * \brief This function is used to add the parsed "http_method" option
+ * into the current signature.
+ *
+ * \param de_ctx Pointer to the Detection Engine Context.
+ * \param s Pointer to the Current Signature.
+ * \param str Pointer to the user provided option string.
+ *
+ * \retval 0 on Success.
+ * \retval -1 on Failure.
+ */
+static int DetectHttpMethodSetup(DetectEngineCtx *de_ctx, Signature *s, const char *str)
+{
+ return DetectEngineContentModifierBufferSetup(
+ de_ctx, s, str, DETECT_AL_HTTP_METHOD, g_http_method_buffer_id, ALPROTO_HTTP1);
+}
+
+/**
+ * \brief this function setup the http.method keyword used in the rule
+ *
+ * \param de_ctx Pointer to the Detection Engine Context
+ * \param s Pointer to the Signature to which the current keyword belongs
+ * \param str Should hold an empty string always
+ *
+ * \retval 0 On success
+ */
+static int DetectHttpMethodSetupSticky(DetectEngineCtx *de_ctx, Signature *s, const char *str)
+{
+ if (DetectBufferSetActiveList(de_ctx, s, g_http_method_buffer_id) < 0)
+ return -1;
+
+ if (DetectSignatureSetAppProto(s, ALPROTO_HTTP) < 0)
+ return -1;
+
+ return 0;
+}
+
+/**
+ * \retval 1 valid
+ * \retval 0 invalid
+ */
+static bool DetectHttpMethodValidateCallback(const Signature *s, const char **sigerror)
+{
+ for (uint32_t x = 0; x < s->init_data->buffer_index; x++) {
+ if (s->init_data->buffers[x].id != (uint32_t)g_http_method_buffer_id)
+ continue;
+ const SigMatch *sm = s->init_data->buffers[x].head;
+ for (; sm != NULL; sm = sm->next) {
+ if (sm->type != DETECT_CONTENT)
+ continue;
+ const DetectContentData *cd = (const DetectContentData *)sm->ctx;
+ if (cd->content && cd->content_len) {
+ if (cd->content[cd->content_len - 1] == 0x20) {
+ *sigerror = "http_method pattern with trailing space";
+ SCLogError("%s", *sigerror);
+ return false;
+ } else if (cd->content[0] == 0x20) {
+ *sigerror = "http_method pattern with leading space";
+ SCLogError("%s", *sigerror);
+ return false;
+ } else if (cd->content[cd->content_len - 1] == 0x09) {
+ *sigerror = "http_method pattern with trailing tab";
+ SCLogError("%s", *sigerror);
+ return false;
+ } else if (cd->content[0] == 0x09) {
+ *sigerror = "http_method pattern with leading tab";
+ SCLogError("%s", *sigerror);
+ return false;
+ }
+ }
+ }
+ }
+ return true;
+}
+
+static InspectionBuffer *GetData(DetectEngineThreadCtx *det_ctx,
+ const DetectEngineTransforms *transforms, Flow *_f,
+ const uint8_t _flow_flags, void *txv, const int list_id)
+{
+ InspectionBuffer *buffer = InspectionBufferGet(det_ctx, list_id);
+ if (buffer->inspect == NULL) {
+ htp_tx_t *tx = (htp_tx_t *)txv;
+
+ if (tx->request_method == NULL)
+ return NULL;
+
+ const uint32_t data_len = bstr_len(tx->request_method);
+ const uint8_t *data = bstr_ptr(tx->request_method);
+
+ InspectionBufferSetup(det_ctx, list_id, buffer, data, data_len);
+ InspectionBufferApplyTransforms(buffer, transforms);
+ }
+
+ return buffer;
+}
+
+static InspectionBuffer *GetData2(DetectEngineThreadCtx *det_ctx,
+ const DetectEngineTransforms *transforms, Flow *_f, const uint8_t _flow_flags, void *txv,
+ const int list_id)
+{
+ InspectionBuffer *buffer = InspectionBufferGet(det_ctx, list_id);
+ if (buffer->inspect == NULL) {
+ uint32_t b_len = 0;
+ const uint8_t *b = NULL;
+
+ if (rs_http2_tx_get_method(txv, &b, &b_len) != 1)
+ return NULL;
+ if (b == NULL || b_len == 0)
+ return NULL;
+
+ InspectionBufferSetup(det_ctx, list_id, buffer, b, b_len);
+ InspectionBufferApplyTransforms(buffer, transforms);
+ }
+
+ return buffer;
+}
+
+#ifdef UNITTESTS
+#include "tests/detect-http-method.c"
+#endif
+
+/**
+ * @}
+ */
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