diff options
Diffstat (limited to 'src/detect-http-header-names.c')
| -rw-r--r-- | src/detect-http-header-names.c | 255 |
1 files changed, 255 insertions, 0 deletions
diff --git a/src/detect-http-header-names.c b/src/detect-http-header-names.c new file mode 100644 index 0000000..58989a1 --- /dev/null +++ b/src/detect-http-header-names.c @@ -0,0 +1,255 @@ +/* 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 "detect-http-header-common.h" +#include "detect-http-header-names.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" + +#define KEYWORD_NAME "http.header_names" +#define KEYWORD_NAME_LEGACY "http_header_names" +#define KEYWORD_DOC "http-keywords.html#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_SIZE_STEP 256 +static HttpHeaderThreadDataConfig g_td_config = { BUFFER_SIZE_STEP }; + +static uint8_t *GetBufferForTX( + htp_tx_t *tx, DetectEngineThreadCtx *det_ctx, Flow *f, uint8_t flags, uint32_t *buffer_len) +{ + *buffer_len = 0; + + HttpHeaderThreadData *hdr_td = NULL; + HttpHeaderBuffer *buf = + HttpHeaderGetBufferSpace(det_ctx, f, flags, g_keyword_thread_id, &hdr_td); + if (unlikely(buf == NULL)) { + return NULL; + } + + htp_table_t *headers; + if (flags & STREAM_TOSERVER) { + if (AppLayerParserGetStateProgress(IPPROTO_TCP, ALPROTO_HTTP1, tx, flags) <= + HTP_REQUEST_HEADERS) + return NULL; + headers = tx->request_headers; + } else { + if (AppLayerParserGetStateProgress(IPPROTO_TCP, ALPROTO_HTTP1, 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 %"PRIuMAX" + buf->len %u vs buf->size %u", + (uintmax_t)size, buf->len, buf->size); + if (size + buf->len > buf->size) { + if (HttpHeaderExpandBuffer(hdr_td, 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; +} + +static InspectionBuffer *GetBuffer1ForTX(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 rawdata_len = 0; + uint8_t *rawdata = GetBufferForTX(txv, det_ctx, f, flow_flags, &rawdata_len); + if (rawdata_len == 0) + return NULL; + + InspectionBufferSetup(det_ctx, list_id, buffer, rawdata, rawdata_len); + InspectionBufferApplyTransforms(buffer, transforms); + } + + return buffer; +} + +static InspectionBuffer *GetBuffer2ForTX(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_header_names(txv, flow_flags, &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; +} + +/** + * \brief The setup function for the http.header_names 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 DetectHttpHeaderNamesSetup(DetectEngineCtx *de_ctx, Signature *s, const char *arg) +{ + if (DetectBufferSetActiveList(de_ctx, s, g_buffer_id) < 0) + return -1; + + if (DetectSignatureSetAppProto(s, ALPROTO_HTTP) < 0) + return -1; + + return 0; +} + +/** + * \brief Registers the keyword handlers for the "http.header_names" keyword. + */ +void DetectHttpHeaderNamesRegister(void) +{ + sigmatch_table[DETECT_AL_HTTP_HEADER_NAMES].name = KEYWORD_NAME; + sigmatch_table[DETECT_AL_HTTP_HEADER_NAMES].alias = KEYWORD_NAME_LEGACY; + sigmatch_table[DETECT_AL_HTTP_HEADER_NAMES].desc = BUFFER_NAME " sticky buffer"; + sigmatch_table[DETECT_AL_HTTP_HEADER_NAMES].url = "/rules/" KEYWORD_DOC; + sigmatch_table[DETECT_AL_HTTP_HEADER_NAMES].Setup = DetectHttpHeaderNamesSetup; + + sigmatch_table[DETECT_AL_HTTP_HEADER_NAMES].flags |= SIGMATCH_NOOPT | SIGMATCH_INFO_STICKY_BUFFER; + + /* http1 */ + DetectAppLayerMpmRegister2(BUFFER_NAME, SIG_FLAG_TOSERVER, 2, PrefilterGenericMpmRegister, + GetBuffer1ForTX, ALPROTO_HTTP1, HTP_REQUEST_HEADERS); + DetectAppLayerMpmRegister2(BUFFER_NAME, SIG_FLAG_TOCLIENT, 2, PrefilterGenericMpmRegister, + GetBuffer1ForTX, ALPROTO_HTTP1, HTP_RESPONSE_HEADERS); + + DetectAppLayerInspectEngineRegister2(BUFFER_NAME, ALPROTO_HTTP1, SIG_FLAG_TOSERVER, + HTP_REQUEST_HEADERS, DetectEngineInspectBufferGeneric, GetBuffer1ForTX); + DetectAppLayerInspectEngineRegister2(BUFFER_NAME, ALPROTO_HTTP1, SIG_FLAG_TOCLIENT, + HTP_RESPONSE_HEADERS, DetectEngineInspectBufferGeneric, GetBuffer1ForTX); + + /* http2 */ + DetectAppLayerMpmRegister2(BUFFER_NAME, SIG_FLAG_TOSERVER, 2, PrefilterGenericMpmRegister, + GetBuffer2ForTX, ALPROTO_HTTP2, HTTP2StateDataClient); + DetectAppLayerMpmRegister2(BUFFER_NAME, SIG_FLAG_TOCLIENT, 2, PrefilterGenericMpmRegister, + GetBuffer2ForTX, ALPROTO_HTTP2, HTTP2StateDataServer); + + DetectAppLayerInspectEngineRegister2(BUFFER_NAME, ALPROTO_HTTP2, SIG_FLAG_TOSERVER, + HTTP2StateDataClient, DetectEngineInspectBufferGeneric, GetBuffer2ForTX); + DetectAppLayerInspectEngineRegister2(BUFFER_NAME, ALPROTO_HTTP2, SIG_FLAG_TOCLIENT, + HTTP2StateDataServer, DetectEngineInspectBufferGeneric, GetBuffer2ForTX); + + DetectBufferTypeSetDescriptionByName(BUFFER_NAME, + BUFFER_DESC); + + g_buffer_id = DetectBufferTypeGetByName(BUFFER_NAME); + + g_keyword_thread_id = DetectRegisterThreadCtxGlobalFuncs(KEYWORD_NAME, + HttpHeaderThreadDataInit, &g_td_config, HttpHeaderThreadDataFree); + + SCLogDebug("keyword %s registered. Thread id %d. " + "Buffer %s registered. Buffer id %d", + KEYWORD_NAME, g_keyword_thread_id, + BUFFER_NAME, g_buffer_id); +} |