diff --git a/src/Makefile.am b/src/Makefile.am index ba9187061d..36033f31db 100755 --- a/src/Makefile.am +++ b/src/Makefile.am @@ -334,6 +334,7 @@ noinst_HEADERS = \ detect-tls-ja3-string.h \ detect-tls-sni.h \ detect-tls-version.h \ + detect-tls-random.h \ detect-tos.h \ detect-transform-compress-whitespace.h \ detect-transform-dotprefix.h \ @@ -931,6 +932,7 @@ libsuricata_c_a_SOURCES = \ detect-tls-ja3-string.c \ detect-tls-sni.c \ detect-tls-version.c \ + detect-tls-random.c \ detect-tos.c \ detect-transform-compress-whitespace.c \ detect-transform-dotprefix.c \ diff --git a/src/app-layer-ssl.c b/src/app-layer-ssl.c index 1cebb2bd2c..22ca455f78 100644 --- a/src/app-layer-ssl.c +++ b/src/app-layer-ssl.c @@ -1,4 +1,4 @@ -/* Copyright (C) 2007-2020 Open Information Security Foundation +/* Copyright (C) 2007-2022 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 @@ -705,6 +705,14 @@ static inline int TLSDecodeHSHelloRandom(SSLState *ssl_state, return -1; } + if (ssl_state->current_flags & SSL_AL_FLAG_STATE_SERVER_HELLO) { + memcpy(ssl_state->server_connp.random, input, TLS_RANDOM_LEN); + ssl_state->flags |= TLS_TS_RANDOM_SET; + } else if (ssl_state->current_flags & SSL_AL_FLAG_STATE_CLIENT_HELLO) { + memcpy(ssl_state->client_connp.random, input, TLS_RANDOM_LEN); + ssl_state->flags |= TLS_TC_RANDOM_SET; + } + /* Skip random */ input += SSLV3_CLIENT_HELLO_RANDOM_LEN; @@ -2682,6 +2690,8 @@ static void *SSLStateAlloc(void *orig_state, AppProto proto_orig) memset(ssl_state, 0, sizeof(SSLState)); ssl_state->client_connp.cert_log_flag = 0; ssl_state->server_connp.cert_log_flag = 0; + memset(ssl_state->client_connp.random, 0, TLS_RANDOM_LEN); + memset(ssl_state->server_connp.random, 0, TLS_RANDOM_LEN); TAILQ_INIT(&ssl_state->server_connp.certs); return (void *)ssl_state; diff --git a/src/app-layer-ssl.h b/src/app-layer-ssl.h index 0a8c0db35c..9c71e949e1 100644 --- a/src/app-layer-ssl.h +++ b/src/app-layer-ssl.h @@ -1,4 +1,4 @@ -/* Copyright (C) 2007-2012 Open Information Security Foundation +/* Copyright (C) 2007-2022 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 @@ -128,6 +128,12 @@ enum { used by 0-RTT. */ #define SSL_AL_FLAG_EARLY_DATA BIT_U32(23) +/* flag to indicate that server random was filled */ +#define TLS_TS_RANDOM_SET BIT_U32(24) + +/* flag to indicate that client random was filled */ +#define TLS_TC_RANDOM_SET BIT_U32(25) + /* config flags */ #define SSL_TLS_LOG_PEM (1 << 0) @@ -145,6 +151,9 @@ enum { /* Max string length of the TLS version string */ #define SSL_VERSION_MAX_STRLEN 20 +/* TLS random bytes for the sticky buffer */ +#define TLS_RANDOM_LEN 32 + /* SSL versions. We'll use a unified format for all, with the top byte * holding the major version and the lower byte the minor version */ enum { @@ -206,6 +215,7 @@ typedef struct SSLStateConnp_ { uint16_t session_id_length; + uint8_t random[TLS_RANDOM_LEN]; char *cert0_subject; char *cert0_issuerdn; char *cert0_serial; diff --git a/src/detect-engine-register.c b/src/detect-engine-register.c index 4ad49cc09d..66e7af8f91 100644 --- a/src/detect-engine-register.c +++ b/src/detect-engine-register.c @@ -53,6 +53,7 @@ #include "detect-tls-cert-issuer.h" #include "detect-tls-cert-subject.h" #include "detect-tls-cert-serial.h" +#include "detect-tls-random.h" #include "detect-tls-ja3-hash.h" #include "detect-tls-ja3-string.h" #include "detect-tls-ja3s-hash.h" @@ -520,6 +521,7 @@ void SigTableSetup(void) DetectTlsSerialRegister(); DetectTlsFingerprintRegister(); DetectTlsCertsRegister(); + DetectTlsRandomRegister(); DetectTlsJa3HashRegister(); DetectTlsJa3StringRegister(); diff --git a/src/detect-engine-register.h b/src/detect-engine-register.h index c6160f5f99..595e656e28 100644 --- a/src/detect-engine-register.h +++ b/src/detect-engine-register.h @@ -221,6 +221,9 @@ enum DetectKeywordId { DETECT_AL_TLS_CERT_SUBJECT, DETECT_AL_TLS_CERT_SERIAL, DETECT_AL_TLS_CERT_FINGERPRINT, + DETECT_AL_TLS_RANDOM_TIME, + DETECT_AL_TLS_RANDOM_BYTES, + DETECT_AL_TLS_RANDOM, DETECT_AL_TLS_JA3_HASH, DETECT_AL_TLS_JA3_STRING, diff --git a/src/detect-tls-random.c b/src/detect-tls-random.c new file mode 100644 index 0000000000..8b8dedc4e9 --- /dev/null +++ b/src/detect-tls-random.c @@ -0,0 +1,284 @@ +/* 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 "debug.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(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(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(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; +} diff --git a/src/detect-tls-random.h b/src/detect-tls-random.h new file mode 100644 index 0000000000..4460a05749 --- /dev/null +++ b/src/detect-tls-random.h @@ -0,0 +1,25 @@ +/* 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. + */ + +#ifndef __DETECT_TLS_RANDOM_H__ +#define __DETECT_TLS_RANDOM_H__ + +void DetectTlsRandomTimeRegister(void); +void DetectTlsRandomBytesRegister(void); +void DetectTlsRandomRegister(void); + +#endif /* __DETECT_TLS_RANDOM_H__ */