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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-19 17:39:49 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-19 17:39:49 +0000 |
commit | a0aa2307322cd47bbf416810ac0292925e03be87 (patch) | |
tree | 37076262a026c4b48c8a0e84f44ff9187556ca35 /src/detect-tls-random.c | |
parent | Initial commit. (diff) | |
download | suricata-a0aa2307322cd47bbf416810ac0292925e03be87.tar.xz suricata-a0aa2307322cd47bbf416810ac0292925e03be87.zip |
Adding upstream version 1:7.0.3.upstream/1%7.0.3
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'src/detect-tls-random.c')
-rw-r--r-- | src/detect-tls-random.c | 283 |
1 files changed, 283 insertions, 0 deletions
diff --git a/src/detect-tls-random.c b/src/detect-tls-random.c new file mode 100644 index 0000000..fc4369a --- /dev/null +++ b/src/detect-tls-random.c @@ -0,0 +1,283 @@ +/* Copyright (C) 2022 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 "suricata-common.h" +#include "threads.h" +#include "detect.h" + +#include "detect-parse.h" +#include "detect-engine.h" +#include "detect-engine-mpm.h" +#include "detect-content.h" + +#include "flow.h" +#include "stream-tcp.h" + +#include "app-layer.h" +#include "app-layer-ssl.h" +#include "detect-engine-prefilter.h" +#include "detect-tls-random.h" + +#define DETECT_TLS_RANDOM_TIME_LEN 4 +#define DETECT_TLS_RANDOM_BYTES_LEN 28 + +static int DetectTlsRandomTimeSetup(DetectEngineCtx *, Signature *, const char *); +static int DetectTlsRandomBytesSetup(DetectEngineCtx *, Signature *, const char *); +static int DetectTlsRandomSetup(DetectEngineCtx *, Signature *, const char *); +static InspectionBuffer *GetRandomTimeData(DetectEngineThreadCtx *det_ctx, + const DetectEngineTransforms *transforms, Flow *f, const uint8_t flow_flags, void *txv, + const int list_id); +static InspectionBuffer *GetRandomBytesData(DetectEngineThreadCtx *det_ctx, + const DetectEngineTransforms *transforms, Flow *f, const uint8_t flow_flags, void *txv, + const int list_id); +static InspectionBuffer *GetRandomData(DetectEngineThreadCtx *det_ctx, + const DetectEngineTransforms *transforms, Flow *f, const uint8_t flow_flags, void *txv, + const int list_id); + +static int g_tls_random_time_buffer_id = 0; +static int g_tls_random_bytes_buffer_id = 0; +static int g_tls_random_buffer_id = 0; + +void DetectTlsRandomTimeRegister(void) +{ + sigmatch_table[DETECT_AL_TLS_RANDOM_TIME].name = "tls.random_time"; + sigmatch_table[DETECT_AL_TLS_RANDOM_TIME].desc = "sticky buffer to match specifically and only " + "on the first 4 bytes of a TLS random buffer"; + sigmatch_table[DETECT_AL_TLS_RANDOM_TIME].url = "/rules/tls-keywords.html#tls-random-time"; + sigmatch_table[DETECT_AL_TLS_RANDOM_TIME].Setup = DetectTlsRandomTimeSetup; + sigmatch_table[DETECT_AL_TLS_RANDOM_TIME].flags |= SIGMATCH_NOOPT | SIGMATCH_INFO_STICKY_BUFFER; + + /* Register engine for Server random */ + DetectAppLayerInspectEngineRegister2("tls.random_time", ALPROTO_TLS, SIG_FLAG_TOSERVER, 0, + DetectEngineInspectBufferGeneric, GetRandomTimeData); + DetectAppLayerMpmRegister2("tls.random_time", SIG_FLAG_TOSERVER, 2, PrefilterGenericMpmRegister, + GetRandomTimeData, ALPROTO_TLS, 0); + + /* Register engine for Client random */ + DetectAppLayerInspectEngineRegister2("tls.random_time", ALPROTO_TLS, SIG_FLAG_TOCLIENT, 0, + DetectEngineInspectBufferGeneric, GetRandomTimeData); + DetectAppLayerMpmRegister2("tls.random_time", SIG_FLAG_TOCLIENT, 2, PrefilterGenericMpmRegister, + GetRandomTimeData, ALPROTO_TLS, 0); + + DetectBufferTypeSetDescriptionByName("tls.random_time", "TLS Random Time"); + + g_tls_random_time_buffer_id = DetectBufferTypeGetByName("tls.random_time"); +} + +void DetectTlsRandomBytesRegister(void) +{ + sigmatch_table[DETECT_AL_TLS_RANDOM_BYTES].name = "tls.random_bytes"; + sigmatch_table[DETECT_AL_TLS_RANDOM_BYTES].desc = + "sticky buffer to match specifically and only on the last 28 bytes of a TLS random " + "buffer"; + sigmatch_table[DETECT_AL_TLS_RANDOM_BYTES].url = "/rules/tls-keywords.html#tls-random-bytes"; + sigmatch_table[DETECT_AL_TLS_RANDOM_BYTES].Setup = DetectTlsRandomBytesSetup; + sigmatch_table[DETECT_AL_TLS_RANDOM_BYTES].flags |= + SIGMATCH_NOOPT | SIGMATCH_INFO_STICKY_BUFFER; + + /* Register engine for Server random */ + DetectAppLayerInspectEngineRegister2("tls.random_bytes", ALPROTO_TLS, SIG_FLAG_TOSERVER, 0, + DetectEngineInspectBufferGeneric, GetRandomBytesData); + DetectAppLayerMpmRegister2("tls.random_bytes", SIG_FLAG_TOSERVER, 2, + PrefilterGenericMpmRegister, GetRandomBytesData, ALPROTO_TLS, 0); + + /* Register engine for Client random */ + DetectAppLayerInspectEngineRegister2("tls.random_bytes", ALPROTO_TLS, SIG_FLAG_TOCLIENT, 0, + DetectEngineInspectBufferGeneric, GetRandomBytesData); + DetectAppLayerMpmRegister2("tls.random_bytes", SIG_FLAG_TOCLIENT, 2, + PrefilterGenericMpmRegister, GetRandomBytesData, ALPROTO_TLS, 0); + + DetectBufferTypeSetDescriptionByName("tls.random_bytes", "TLS Random Bytes"); + + g_tls_random_bytes_buffer_id = DetectBufferTypeGetByName("tls.random_bytes"); +} + +/** + * \brief Registration function for keyword: tls.random + */ +void DetectTlsRandomRegister(void) +{ + DetectTlsRandomTimeRegister(); + DetectTlsRandomBytesRegister(); + + sigmatch_table[DETECT_AL_TLS_RANDOM].name = "tls.random"; + sigmatch_table[DETECT_AL_TLS_RANDOM].desc = + "sticky buffer to match specifically and only on a TLS random buffer"; + sigmatch_table[DETECT_AL_TLS_RANDOM].url = "/rules/tls-keywords.html#tls-random"; + sigmatch_table[DETECT_AL_TLS_RANDOM].Setup = DetectTlsRandomSetup; + sigmatch_table[DETECT_AL_TLS_RANDOM].flags |= SIGMATCH_NOOPT | SIGMATCH_INFO_STICKY_BUFFER; + + /* Register engine for Server random */ + DetectAppLayerInspectEngineRegister2("tls.random", ALPROTO_TLS, SIG_FLAG_TOSERVER, 0, + DetectEngineInspectBufferGeneric, GetRandomData); + DetectAppLayerMpmRegister2("tls.random", SIG_FLAG_TOSERVER, 2, PrefilterGenericMpmRegister, + GetRandomData, ALPROTO_TLS, 0); + + /* Register engine for Client random */ + DetectAppLayerInspectEngineRegister2("tls.random", ALPROTO_TLS, SIG_FLAG_TOCLIENT, 0, + DetectEngineInspectBufferGeneric, GetRandomData); + DetectAppLayerMpmRegister2("tls.random", SIG_FLAG_TOCLIENT, 2, PrefilterGenericMpmRegister, + GetRandomData, ALPROTO_TLS, 0); + + DetectBufferTypeSetDescriptionByName("tls.random", "TLS Random"); + + g_tls_random_buffer_id = DetectBufferTypeGetByName("tls.random"); +} + +/** + * \brief this function setup the tls.random_time sticky buffer 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 + * \retval -1 On failure + */ +static int DetectTlsRandomTimeSetup(DetectEngineCtx *de_ctx, Signature *s, const char *str) +{ + if (DetectBufferSetActiveList(de_ctx, s, g_tls_random_time_buffer_id) < 0) + return -1; + + if (DetectSignatureSetAppProto(s, ALPROTO_TLS) < 0) + return -1; + + return 0; +} + +/** + * \brief this function setup the tls.random_bytes sticky buffer 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 + * \retval -1 On failure + */ +static int DetectTlsRandomBytesSetup(DetectEngineCtx *de_ctx, Signature *s, const char *str) +{ + if (DetectBufferSetActiveList(de_ctx, s, g_tls_random_bytes_buffer_id) < 0) + return -1; + + if (DetectSignatureSetAppProto(s, ALPROTO_TLS) < 0) + return -1; + + return 0; +} + +/** + * \brief this function setup the tls.random sticky buffer 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 + * \retval -1 On failure + */ +static int DetectTlsRandomSetup(DetectEngineCtx *de_ctx, Signature *s, const char *str) +{ + if (DetectBufferSetActiveList(de_ctx, s, g_tls_random_buffer_id) < 0) + return -1; + + if (DetectSignatureSetAppProto(s, ALPROTO_TLS) < 0) + return -1; + + return 0; +} + +static InspectionBuffer *GetRandomTimeData(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) { + const SSLState *ssl_state = (SSLState *)f->alstate; + if (flow_flags & STREAM_TOSERVER) { + if (!(ssl_state->flags & TLS_TS_RANDOM_SET)) + return NULL; + } else { + if (!(ssl_state->flags & TLS_TC_RANDOM_SET)) + return NULL; + } + const uint32_t data_len = DETECT_TLS_RANDOM_TIME_LEN; + const uint8_t *data; + if (flow_flags & STREAM_TOSERVER) { + data = ssl_state->server_connp.random; + } else { + data = ssl_state->client_connp.random; + } + InspectionBufferSetup(det_ctx, list_id, buffer, data, data_len); + InspectionBufferApplyTransforms(buffer, transforms); + } + return buffer; +} + +static InspectionBuffer *GetRandomBytesData(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) { + const SSLState *ssl_state = (SSLState *)f->alstate; + if (flow_flags & STREAM_TOSERVER) { + if (!(ssl_state->flags & TLS_TS_RANDOM_SET)) + return NULL; + } else { + if (!(ssl_state->flags & TLS_TC_RANDOM_SET)) + return NULL; + } + const uint32_t data_len = DETECT_TLS_RANDOM_BYTES_LEN; + const uint8_t *data; + if (flow_flags & STREAM_TOSERVER) { + data = ssl_state->server_connp.random + DETECT_TLS_RANDOM_TIME_LEN; + } else { + data = ssl_state->client_connp.random + DETECT_TLS_RANDOM_TIME_LEN; + } + InspectionBufferSetup(det_ctx, list_id, buffer, data, data_len); + InspectionBufferApplyTransforms(buffer, transforms); + } + return buffer; +} + +static InspectionBuffer *GetRandomData(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) { + const SSLState *ssl_state = (SSLState *)f->alstate; + if (flow_flags & STREAM_TOSERVER) { + if (!(ssl_state->flags & TLS_TS_RANDOM_SET)) + return NULL; + } else { + if (!(ssl_state->flags & TLS_TC_RANDOM_SET)) + return NULL; + } + const uint32_t data_len = TLS_RANDOM_LEN; + const uint8_t *data; + if (flow_flags & STREAM_TOSERVER) { + data = ssl_state->server_connp.random; + } else { + data = ssl_state->client_connp.random; + } + InspectionBufferSetup(det_ctx, list_id, buffer, data, data_len); + InspectionBufferApplyTransforms(buffer, transforms); + } + return buffer; +} |