From 88cfb99910f3b70ea565fcf9635f86afdaf46f1e Mon Sep 17 00:00:00 2001 From: Victor Julien Date: Sat, 1 Apr 2017 11:49:20 +0200 Subject: [PATCH] detect: http_accept sticky buffer + common code Implement common code to easily add more per HTTP header detection keywords. Implement http_accept sticky buffer. It operates on the HTTP Accept header. --- src/Makefile.am | 2 + src/detect-http-accept.c | 46 +++++ src/detect-http-accept.h | 23 +++ src/detect-http-headers-stub.h | 363 +++++++++++++++++++++++++++++++++ src/detect-http-headers.c | 23 +++ src/detect-http-headers.h | 23 +++ src/detect.c | 2 + src/detect.h | 1 + 8 files changed, 483 insertions(+) create mode 100644 src/detect-http-accept.c create mode 100644 src/detect-http-accept.h create mode 100644 src/detect-http-headers-stub.h create mode 100644 src/detect-http-headers.c create mode 100644 src/detect-http-headers.h diff --git a/src/Makefile.am b/src/Makefile.am index f5ecd6afa1..01b1114a17 100644 --- a/src/Makefile.am +++ b/src/Makefile.am @@ -163,9 +163,11 @@ detect-ftpbounce.c detect-ftpbounce.h \ detect-geoip.c detect-geoip.h \ detect-gid.c detect-gid.h \ detect-hostbits.c detect-hostbits.h \ +detect-http-accept.c detect-http-accept.h \ detect-http-client-body.c detect-http-client-body.h \ detect-http-cookie.c detect-http-cookie.h \ detect-http-header.c detect-http-header.h \ +detect-http-headers.c detect-http-headers.h detect-http-headers-stub.h \ detect-http-header-common.c detect-http-header-common.h \ detect-http-header-names.c detect-http-header-names.h \ detect-http-hh.c detect-http-hh.h \ diff --git a/src/detect-http-accept.c b/src/detect-http-accept.c new file mode 100644 index 0000000000..080bf4eeaf --- /dev/null +++ b/src/detect-http-accept.c @@ -0,0 +1,46 @@ +/* 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 + * + * Implements support http_header_* + */ + +#define KEYWORD_NAME "http_accept" +#define KEYWORD_DOC "http-keywords#http-accept" +#define BUFFER_NAME "http_accept" +#define BUFFER_DESC "http accept header" +#define HEADER_NAME "Accept" +#define KEYWORD_ID DETECT_AL_HTTP_HEADER_ACCEPT +#define KEYWORD_TOSERVER 1 + +#include "detect-http-headers-stub.h" + +void RegisterHttpHeadersAccept(void) +{ + DetectHttpHeadersRegisterStub(); +} diff --git a/src/detect-http-accept.h b/src/detect-http-accept.h new file mode 100644 index 0000000000..c3924af980 --- /dev/null +++ b/src/detect-http-accept.h @@ -0,0 +1,23 @@ +/* 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. + */ + +#ifndef __DETECT_HTTP_ACCEPT_H__ +#define __DETECT_HTTP_ACCEPT_H__ + +void RegisterHttpHeadersAccept(void); + +#endif /* __DETECT_HTTP_ACCEPT_H__ */ diff --git a/src/detect-http-headers-stub.h b/src/detect-http-headers-stub.h new file mode 100644 index 0000000000..b6f7331205 --- /dev/null +++ b/src/detect-http-headers-stub.h @@ -0,0 +1,363 @@ +/* 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); +} diff --git a/src/detect-http-headers.c b/src/detect-http-headers.c new file mode 100644 index 0000000000..fda7f53dcf --- /dev/null +++ b/src/detect-http-headers.c @@ -0,0 +1,23 @@ +/* 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. + */ + +#include "detect-http-accept.h" + +void DetectHttpHeadersRegister(void) +{ + RegisterHttpHeadersAccept(); +} diff --git a/src/detect-http-headers.h b/src/detect-http-headers.h new file mode 100644 index 0000000000..30b9bc59d0 --- /dev/null +++ b/src/detect-http-headers.h @@ -0,0 +1,23 @@ +/* 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. + */ + +#ifndef __DETECT_HTTP_HEADERS_H__ +#define __DETECT_HTTP_HEADERS_H__ + +void DetectHttpHeadersRegister(void); + +#endif /* __DETECT_HTTP_HEADERS_H__ */ diff --git a/src/detect.c b/src/detect.c index 21bffc78ba..728c5c5bbf 100644 --- a/src/detect.c +++ b/src/detect.c @@ -140,6 +140,7 @@ #include "detect-http-server-body.h" #include "detect-http-header.h" #include "detect-http-header-names.h" +#include "detect-http-headers.h" #include "detect-http-raw-header.h" #include "detect-http-uri.h" #include "detect-http-protocol.h" @@ -3948,6 +3949,7 @@ void SigTableSetup(void) DetectHttpServerBodyRegister(); DetectHttpHeaderRegister(); DetectHttpHeaderNamesRegister(); + DetectHttpHeadersRegister(); DetectHttpProtocolRegister(); DetectHttpStartRegister(); DetectHttpRawHeaderRegister(); diff --git a/src/detect.h b/src/detect.h index 93b52bd3c5..672fc1f023 100644 --- a/src/detect.h +++ b/src/detect.h @@ -1241,6 +1241,7 @@ enum { DETECT_AL_HTTP_SERVER_BODY, DETECT_AL_HTTP_HEADER, DETECT_AL_HTTP_HEADER_NAMES, + DETECT_AL_HTTP_HEADER_ACCEPT, DETECT_AL_HTTP_RAW_HEADER, DETECT_AL_HTTP_URI, DETECT_AL_HTTP_RAW_URI,