--- /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.
+ */
+
+/**
+ * \ingroup httplayer
+ *
+ * @{
+ */
+
+
+/**
+ * \file
+ *
+ * \author Victor Julien <victor@inliniac.net>
+ *
+ * Implements support http_header_names
+ */
+
+#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-state.h"
+#include "detect-engine-prefilter.h"
+#include "detect-engine-content-inspection.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 "util-print.h"
+
+#include "app-layer.h"
+#include "app-layer-parser.h"
+
+#include "app-layer-htp.h"
+#include "detect-http-header.h"
+#include "stream-tcp.h"
+
+#include "util-print.h"
+
+#define KEYWORD_NAME "http_header_names"
+#define KEYWORD_DOC "http-keywords#http-header-names"
+#define BUFFER_NAME "http_header_names"
+#define BUFFER_DESC "http header names"
+static int g_buffer_id = 0;
+static int g_keyword_thread_id = 0;
+
+#define BUFFER_TX_STEP 4
+#define BUFFER_SIZE_STEP 256
+
+typedef struct Buffer_ {
+ uint8_t *buffer;
+ uint32_t size; /**< buffer size */
+ uint32_t len; /**< part of buffer in use */
+} Buffer;
+
+typedef struct HttpHeaderNamesThreadData_ {
+ Buffer *buffers; /**< array of buffers */
+ uint16_t buffers_size; /**< number of buffers */
+ uint16_t buffers_list_len;
+ uint64_t start_tx_id;
+ uint64_t tick;
+} HttpHeaderNamesThreadData;
+
+static inline int CreateSpace(HttpHeaderNamesThreadData *hn, uint64_t size);
+static inline int ExpandBuffer(Buffer *buf, uint32_t size);
+
+static void *HttpHeaderNamesThreadDataInit(void *data)
+{
+ HttpHeaderNamesThreadData *d = SCCalloc(1, sizeof(*d));
+ if (d != NULL) {
+ /* initialize minimal buffers */
+ (void)CreateSpace(d, 1);
+ int i;
+ for (i = 0; i < d->buffers_size; i++) {
+ (void)ExpandBuffer(&d->buffers[i], 1);
+ }
+ }
+ return d;
+}
+
+static void HttpHeaderNamesThreadDataFree(void *data)
+{
+ HttpHeaderNamesThreadData *hdrnames = data;
+
+ int i;
+ for (i = 0; i < hdrnames->buffers_size; i++) {
+ if (hdrnames->buffers[i].buffer)
+ SCFree(hdrnames->buffers[i].buffer);
+ if (hdrnames->buffers[i].size) {
+ SCLogDebug("hdrnames->buffers[%d].size %u (%u)",
+ i, hdrnames->buffers[i].size, hdrnames->buffers_size);
+ }
+ }
+ SCFree(hdrnames->buffers);
+ SCFree(hdrnames);
+}
+
+static void Reset(HttpHeaderNamesThreadData *hdrnames, uint64_t tick)
+{
+ uint16_t i;
+ for (i = 0; i < hdrnames->buffers_list_len; i++) {
+ hdrnames->buffers[i].len = 0;
+ }
+ hdrnames->buffers_list_len = 0;
+ hdrnames->start_tx_id = 0;
+ hdrnames->tick = tick;
+}
+
+static inline int CreateSpace(HttpHeaderNamesThreadData *hn, uint64_t size)
+{
+ if (size >= SHRT_MAX)
+ return -1;
+
+ if (size > hn->buffers_size) {
+ uint16_t extra = BUFFER_TX_STEP;
+ while (hn->buffers_size + extra < size) {
+ extra += BUFFER_TX_STEP;
+ }
+ SCLogDebug("adding %u to the buffer", (uint)extra);
+
+ void *ptmp = SCRealloc(hn->buffers,
+ (hn->buffers_size + extra) * sizeof(Buffer));
+ if (ptmp == NULL) {
+ SCFree(hn->buffers);
+ hn->buffers = NULL;
+ hn->buffers_size = 0;
+ hn->buffers_list_len = 0;
+ return -1;
+ }
+ hn->buffers = ptmp;
+ memset(hn->buffers + hn->buffers_size, 0, extra * sizeof(Buffer));
+ hn->buffers_size += extra;
+ }
+
+ return 0;
+}
+
+static inline int ExpandBuffer(Buffer *buf, uint32_t size)
+{
+ size_t extra = BUFFER_SIZE_STEP;
+ while ((buf->size + extra) < (size + buf->len)) {
+ extra += BUFFER_SIZE_STEP;
+ }
+ SCLogDebug("adding %u to the buffer", (uint)extra);
+
+ uint8_t *new_buffer = SCRealloc(buf->buffer, buf->size + extra);
+ if (unlikely(new_buffer == NULL)) {
+ buf->len = 0;
+ return -1;
+ }
+ buf->buffer = new_buffer;
+ buf->size += extra;
+ return 0;
+}
+
+static Buffer *GetBufferSpaceForTXID(DetectEngineThreadCtx *det_ctx,
+ Flow *f, uint8_t flags, uint64_t tx_id)
+{
+ int index = 0;
+
+ HttpHeaderNamesThreadData *hdrnames =
+ DetectThreadCtxGetGlobalKeywordThreadCtx(det_ctx, g_keyword_thread_id);
+ if (hdrnames == NULL)
+ return NULL;
+ if (hdrnames->tick != det_ctx->ticker)
+ Reset(hdrnames, det_ctx->ticker);
+
+ if (hdrnames->buffers_list_len == 0) {
+ /* get the inspect id to use as a 'base id' */
+ uint64_t base_inspect_id = AppLayerParserGetTransactionInspectId(f->alparser, flags);
+ BUG_ON(base_inspect_id > tx_id);
+ /* see how many space we need for the current tx_id */
+ uint64_t txs = (tx_id - base_inspect_id) + 1;
+ if (CreateSpace(hdrnames, txs) < 0)
+ return NULL;
+
+ index = (tx_id - base_inspect_id);
+ hdrnames->start_tx_id = base_inspect_id;
+ hdrnames->buffers_list_len = txs;
+ } else {
+ /* tx fits in our current buffers */
+ if ((tx_id - hdrnames->start_tx_id) < hdrnames->buffers_list_len) {
+ /* if we previously reassembled, return that buffer */
+ if (hdrnames->buffers[(tx_id - hdrnames->start_tx_id)].len != 0) {
+ return &hdrnames->buffers[(tx_id - hdrnames->start_tx_id)];
+ }
+ /* otherwise fall through */
+ } else {
+ /* not enough space, lets expand */
+ uint64_t txs = (tx_id - hdrnames->start_tx_id) + 1;
+ if (CreateSpace(hdrnames, txs) < 0)
+ return NULL;
+
+ hdrnames->buffers_list_len = txs;
+ }
+ index = (tx_id - hdrnames->start_tx_id);
+ }
+ Buffer *buf = &hdrnames->buffers[index];
+ return buf;
+}
+
+static uint8_t *GetBufferForTX(htp_tx_t *tx, uint64_t tx_id,
+ DetectEngineCtx *de_ctx, DetectEngineThreadCtx *det_ctx,
+ Flow *f, HtpState *htp_state, uint8_t flags,
+ uint32_t *buffer_len)
+{
+ *buffer_len = 0;
+
+ Buffer *buf = GetBufferSpaceForTXID(det_ctx, f, flags, tx_id);
+ if (unlikely(buf == NULL)) {
+ return NULL;
+ } else if (buf->len > 0) {
+ /* already filled buf, reuse */
+ *buffer_len = buf->len;
+ return buf->buffer;
+ }
+
+ htp_table_t *headers;
+ if (flags & STREAM_TOSERVER) {
+ if (AppLayerParserGetStateProgress(IPPROTO_TCP, ALPROTO_HTTP, tx, flags) <=
+ HTP_REQUEST_HEADERS)
+ return NULL;
+ headers = tx->request_headers;
+ } else {
+ if (AppLayerParserGetStateProgress(IPPROTO_TCP, ALPROTO_HTTP, tx, flags) <=
+ HTP_RESPONSE_HEADERS)
+ return NULL;
+ headers = tx->response_headers;
+ }
+ if (headers == NULL)
+ return NULL;
+
+ /* fill the buffer. \r\nName1\r\nName2\r\n\r\n */
+ size_t i = 0;
+ size_t no_of_headers = htp_table_size(headers);
+ for (; i < no_of_headers; i++) {
+ htp_header_t *h = htp_table_get_index(headers, i, NULL);
+ size_t size = bstr_size(h->name) + 2; // for \r\n
+ if (i == 0)
+ size += 2;
+ if (i + 1 == no_of_headers)
+ size += 2;
+
+ SCLogDebug("size %u + buf->len %u vs buf->size %u", (uint)size, buf->len, buf->size);
+ if (size + buf->len > buf->size) {
+ if (ExpandBuffer(buf, size) != 0) {
+ return NULL;
+ }
+ }
+
+ /* start with a \r\n */
+ if (i == 0) {
+ buf->buffer[buf->len++] = '\r';
+ buf->buffer[buf->len++] = '\n';
+ }
+
+ memcpy(buf->buffer + buf->len, bstr_ptr(h->name), bstr_size(h->name));
+ buf->len += bstr_size(h->name);
+ buf->buffer[buf->len++] = '\r';
+ buf->buffer[buf->len++] = '\n';
+
+ /* end with an extra \r\n */
+ if (i + 1 == no_of_headers) {
+ buf->buffer[buf->len++] = '\r';
+ buf->buffer[buf->len++] = '\n';
+ }
+ }
+
+ *buffer_len = buf->len;
+ return buf->buffer;
+}
+
+/** \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 PrefilterTxHttpRequestHeaderNames(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;
+
+ HtpState *htp_state = f->alstate;
+ uint32_t buffer_len = 0;
+ const uint8_t *buffer = GetBufferForTX(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);
+ }
+}
+#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
+int PrefilterTxHttpRequestHeaderNamesRegister(SigGroupHead *sgh, MpmCtx *mpm_ctx)
+{
+ SCEnter();
+
+ int r = PrefilterAppendTxEngine(sgh, PrefilterTxHttpRequestHeaderNames,
+ 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
+}
+
+/** \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 PrefilterTxHttpResponseHeaderNames(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;
+
+ HtpState *htp_state = f->alstate;
+ uint32_t buffer_len = 0;
+ const uint8_t *buffer = GetBufferForTX(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);
+ }
+}
+#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
+int PrefilterTxHttpResponseHeaderNamesRegister(SigGroupHead *sgh, MpmCtx *mpm_ctx)
+{
+ SCEnter();
+
+ int r = PrefilterAppendTxEngine(sgh, PrefilterTxHttpResponseHeaderNames,
+ ALPROTO_HTTP, HTP_RESPONSE_HEADERS,
+ mpm_ctx, NULL, KEYWORD_NAME " (response)");
+ return r;
+#if 0
+ if (r != 0)
+ return r;
+ return PrefilterAppendTxEngine(sgh, PrefilterTxHttpResponseTrailers,
+ ALPROTO_HTTP, HTP_RESPONSE_TRAILER,
+ mpm_ctx, NULL, "http_header (response)");
+#endif
+}
+
+int InspectEngineHttpHeaderNames(ThreadVars *tv,
+ DetectEngineCtx *de_ctx, DetectEngineThreadCtx *det_ctx,
+ const Signature *s, const SigMatchData *smd,
+ Flow *f, uint8_t flags, void *alstate, void *tx, uint64_t tx_id)
+{
+ HtpState *htp_state = (HtpState *)alstate;
+ uint32_t buffer_len = 0;
+ uint8_t *buffer = GetBufferForTX(tx, tx_id,
+ de_ctx, det_ctx, f, htp_state,
+ flags, &buffer_len);
+ 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 (flags & STREAM_TOSERVER) {
+ if (AppLayerParserGetStateProgress(IPPROTO_TCP, ALPROTO_HTTP, tx, flags) > HTP_REQUEST_HEADERS)
+ return DETECT_ENGINE_INSPECT_SIG_CANT_MATCH;
+ } else {
+ if (AppLayerParserGetStateProgress(IPPROTO_TCP, ALPROTO_HTTP, tx, flags) > HTP_RESPONSE_HEADERS)
+ return DETECT_ENGINE_INSPECT_SIG_CANT_MATCH;
+ }
+ return DETECT_ENGINE_INSPECT_SIG_NO_MATCH;
+}
+
+/**
+ * \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.
+ */
+int DetectHttpHeaderNamesSetup(DetectEngineCtx *de_ctx, Signature *s, char *arg)
+{
+ s->init_data->list = g_buffer_id;
+ return 0;
+}
+
+static void DetectHttpHeaderNamesSetupCallback(Signature *s)
+{
+ SCLogDebug("callback invoked by %u", s->id);
+ s->mask |= SIG_MASK_REQUIRE_HTTP_STATE;
+}
+
+/**
+ * \brief Registers the keyword handlers for the "http_header" keyword.
+ */
+void DetectHttpHeaderNamesRegister(void)
+{
+ sigmatch_table[DETECT_AL_HTTP_HEADER_NAMES].name = KEYWORD_NAME;
+ sigmatch_table[DETECT_AL_HTTP_HEADER_NAMES].desc = BUFFER_NAME " sticky buffer";
+ sigmatch_table[DETECT_AL_HTTP_HEADER_NAMES].url = DOC_URL DOC_VERSION "/rules/" KEYWORD_DOC;
+ sigmatch_table[DETECT_AL_HTTP_HEADER_NAMES].Setup = DetectHttpHeaderNamesSetup;
+
+ sigmatch_table[DETECT_AL_HTTP_HEADER_NAMES].flags |= SIGMATCH_NOOPT ;
+ sigmatch_table[DETECT_AL_HTTP_HEADER_NAMES].flags |= SIGMATCH_PAYLOAD ;
+
+ DetectAppLayerMpmRegister(BUFFER_NAME, SIG_FLAG_TOSERVER, 2,
+ PrefilterTxHttpRequestHeaderNamesRegister);
+ DetectAppLayerMpmRegister(BUFFER_NAME, SIG_FLAG_TOCLIENT, 2,
+ PrefilterTxHttpResponseHeaderNamesRegister);
+
+ DetectAppLayerInspectEngineRegister(BUFFER_NAME,
+ ALPROTO_HTTP, SIG_FLAG_TOSERVER,
+ InspectEngineHttpHeaderNames);
+ DetectAppLayerInspectEngineRegister(BUFFER_NAME,
+ ALPROTO_HTTP, SIG_FLAG_TOCLIENT,
+ InspectEngineHttpHeaderNames);
+
+ DetectBufferTypeSetDescriptionByName(BUFFER_NAME,
+ BUFFER_DESC);
+
+ DetectBufferTypeRegisterSetupCallback(BUFFER_NAME,
+ DetectHttpHeaderNamesSetupCallback);
+
+ g_buffer_id = DetectBufferTypeGetByName(BUFFER_NAME);
+
+ g_keyword_thread_id = DetectRegisterThreadCtxGlobalFuncs(KEYWORD_NAME,
+ HttpHeaderNamesThreadDataInit, HttpHeaderNamesThreadDataFree);
+
+ SCLogDebug("keyword %s registered. Thread id %d. "
+ "Buffer %s registered. Buffer id %d",
+ KEYWORD_NAME, g_keyword_thread_id,
+ BUFFER_NAME, g_buffer_id);
+}
projects / thirdparty / suricata.git / commitdiff
