summaryrefslogtreecommitdiffstats
path: root/src/detect-ssl-state.c
diff options
context:
space:
mode:
authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-19 17:39:49 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-19 17:39:49 +0000
commita0aa2307322cd47bbf416810ac0292925e03be87 (patch)
tree37076262a026c4b48c8a0e84f44ff9187556ca35 /src/detect-ssl-state.c
parentInitial commit. (diff)
downloadsuricata-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-ssl-state.c')
-rw-r--r--src/detect-ssl-state.c348
1 files changed, 348 insertions, 0 deletions
diff --git a/src/detect-ssl-state.c b/src/detect-ssl-state.c
new file mode 100644
index 0000000..3f2df48
--- /dev/null
+++ b/src/detect-ssl-state.c
@@ -0,0 +1,348 @@
+/* Copyright (C) 2007-2020 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.
+ */
+
+/**
+ * \file
+ *
+ * \author Anoop Saldanha <anoopsaldanha@gmail.com>
+ *
+ * Implements support for ssl_state keyword.
+ */
+
+#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 "flow.h"
+#include "flow-var.h"
+#include "flow-util.h"
+
+#include "util-debug.h"
+#include "util-unittest.h"
+#include "util-unittest-helper.h"
+
+#include "app-layer.h"
+#include "app-layer-parser.h"
+
+#include "detect-ssl-state.h"
+
+#include "stream-tcp.h"
+#include "app-layer-ssl.h"
+
+#define PARSE_REGEX1 "^(!?)([_a-zA-Z0-9]+)(.*)$"
+static DetectParseRegex parse_regex1;
+
+#define PARSE_REGEX2 "^(?:\\s*[|,]\\s*(!?)([_a-zA-Z0-9]+))(.*)$"
+static DetectParseRegex parse_regex2;
+
+static int DetectSslStateMatch(DetectEngineThreadCtx *,
+ Flow *, uint8_t, void *, void *,
+ const Signature *, const SigMatchCtx *);
+static int DetectSslStateSetup(DetectEngineCtx *, Signature *, const char *);
+#ifdef UNITTESTS
+static void DetectSslStateRegisterTests(void);
+#endif
+static void DetectSslStateFree(DetectEngineCtx *, void *);
+
+static int g_tls_generic_list_id = 0;
+
+/**
+ * \brief Registers the keyword handlers for the "ssl_state" keyword.
+ */
+void DetectSslStateRegister(void)
+{
+ sigmatch_table[DETECT_AL_SSL_STATE].name = "ssl_state";
+ sigmatch_table[DETECT_AL_SSL_STATE].desc = "match the state of the SSL connection";
+ sigmatch_table[DETECT_AL_SSL_STATE].url = "/rules/tls-keywords.html#ssl-state";
+ sigmatch_table[DETECT_AL_SSL_STATE].AppLayerTxMatch = DetectSslStateMatch;
+ sigmatch_table[DETECT_AL_SSL_STATE].Setup = DetectSslStateSetup;
+ sigmatch_table[DETECT_AL_SSL_STATE].Free = DetectSslStateFree;
+#ifdef UNITTESTS
+ sigmatch_table[DETECT_AL_SSL_STATE].RegisterTests = DetectSslStateRegisterTests;
+#endif
+ DetectSetupParseRegexes(PARSE_REGEX1, &parse_regex1);
+ DetectSetupParseRegexes(PARSE_REGEX2, &parse_regex2);
+
+ g_tls_generic_list_id = DetectBufferTypeRegister("tls_generic");
+
+ DetectBufferTypeSetDescriptionByName("tls_generic",
+ "generic ssl/tls inspection");
+
+ DetectAppLayerInspectEngineRegister2(
+ "tls_generic", ALPROTO_TLS, SIG_FLAG_TOSERVER, 0, DetectEngineInspectGenericList, NULL);
+ DetectAppLayerInspectEngineRegister2(
+ "tls_generic", ALPROTO_TLS, SIG_FLAG_TOCLIENT, 0, DetectEngineInspectGenericList, NULL);
+}
+
+/**
+ * \brief App layer match function ssl_state keyword.
+ *
+ * \param tv Pointer to threadvars.
+ * \param det_ctx Pointer to the thread's detection context.
+ * \param f Pointer to the flow.
+ * \param flags Flags.
+ * \param state App layer state.
+ * \param s Sig we are currently inspecting.
+ * \param m SigMatch we are currently inspecting.
+ *
+ * \retval 1 Match.
+ * \retval 0 No match.
+ */
+static int DetectSslStateMatch(DetectEngineThreadCtx *det_ctx,
+ Flow *f, uint8_t flags, void *alstate, void *txv,
+ const Signature *s, const SigMatchCtx *m)
+{
+ const DetectSslStateData *ssd = (const DetectSslStateData *)m;
+ SSLState *ssl_state = (SSLState *)alstate;
+ if (ssl_state == NULL) {
+ SCLogDebug("no app state, no match");
+ return 0;
+ }
+
+ uint32_t ssl_flags = ssl_state->current_flags;
+
+ if ((ssd->flags & ssl_flags) ^ ssd->mask) {
+ return 1;
+ }
+
+ return 0;
+}
+
+/**
+ * \brief Parse the arg supplied with ssl_state and return it in a
+ * DetectSslStateData instance.
+ *
+ * \param arg Pointer to the string to be parsed.
+ *
+ * \retval ssd Pointer to DetectSslStateData on success.
+ * \retval NULL On failure.
+ */
+static DetectSslStateData *DetectSslStateParse(const char *arg)
+{
+ size_t pcre2len;
+ char str1[64];
+ char str2[64];
+ int negate = 0;
+ uint32_t flags = 0, mask = 0;
+ DetectSslStateData *ssd = NULL;
+
+ pcre2_match_data *match = NULL;
+ int ret = DetectParsePcreExec(&parse_regex1, &match, arg, 0, 0);
+ if (ret < 1) {
+ SCLogError("Invalid arg \"%s\" supplied to "
+ "ssl_state keyword.",
+ arg);
+ goto error;
+ }
+
+ pcre2len = sizeof(str1);
+ int res = pcre2_substring_copy_bynumber(match, 1, (PCRE2_UCHAR8 *)str1, &pcre2len);
+ if (res < 0) {
+ SCLogError("pcre2_substring_copy_bynumber failed");
+ goto error;
+ }
+ negate = !strcmp("!", str1);
+
+ pcre2len = sizeof(str1);
+ res = pcre2_substring_copy_bynumber(match, 2, (PCRE2_UCHAR8 *)str1, &pcre2len);
+ if (res < 0) {
+ SCLogError("pcre2_substring_copy_bynumber failed");
+ goto error;
+ }
+
+ if (strcmp("client_hello", str1) == 0) {
+ flags |= DETECT_SSL_STATE_CLIENT_HELLO;
+ if (negate)
+ mask |= DETECT_SSL_STATE_CLIENT_HELLO;
+ } else if (strcmp("server_hello", str1) == 0) {
+ flags |= DETECT_SSL_STATE_SERVER_HELLO;
+ if (negate)
+ mask |= DETECT_SSL_STATE_SERVER_HELLO;
+ } else if (strcmp("client_keyx", str1) == 0) {
+ flags |= DETECT_SSL_STATE_CLIENT_KEYX;
+ if (negate)
+ mask |= DETECT_SSL_STATE_CLIENT_KEYX;
+ } else if (strcmp("server_keyx", str1) == 0) {
+ flags |= DETECT_SSL_STATE_SERVER_KEYX;
+ if (negate)
+ mask |= DETECT_SSL_STATE_SERVER_KEYX;
+ } else if (strcmp("unknown", str1) == 0) {
+ flags |= DETECT_SSL_STATE_UNKNOWN;
+ if (negate)
+ mask |= DETECT_SSL_STATE_UNKNOWN;
+ } else {
+ SCLogError("Found invalid option \"%s\" "
+ "in ssl_state keyword.",
+ str1);
+ goto error;
+ }
+
+ pcre2len = sizeof(str1);
+ res = pcre2_substring_copy_bynumber(match, 3, (PCRE2_UCHAR8 *)str1, &pcre2len);
+ if (res < 0) {
+ SCLogError("pcre2_substring_copy_bynumber failed");
+ goto error;
+ }
+ while (res >= 0 && strlen(str1) > 0) {
+ pcre2_match_data *match2 = NULL;
+ ret = DetectParsePcreExec(&parse_regex2, &match2, str1, 0, 0);
+ if (ret < 1) {
+ SCLogError("Invalid arg \"%s\" supplied to "
+ "ssl_state keyword.",
+ arg);
+ if (match2) {
+ pcre2_match_data_free(match2);
+ }
+ goto error;
+ }
+
+ pcre2len = sizeof(str2);
+ res = pcre2_substring_copy_bynumber(match2, 1, (PCRE2_UCHAR8 *)str2, &pcre2len);
+ if (res < 0) {
+ SCLogError("pcre2_substring_copy_bynumber failed");
+ pcre2_match_data_free(match2);
+ goto error;
+ }
+ negate = !strcmp("!", str2);
+
+ pcre2len = sizeof(str2);
+ res = pcre2_substring_copy_bynumber(match2, 2, (PCRE2_UCHAR8 *)str2, &pcre2len);
+ if (res < 0) {
+ SCLogError("pcre2_substring_copy_bynumber failed");
+ pcre2_match_data_free(match2);
+ goto error;
+ }
+ if (strcmp("client_hello", str2) == 0) {
+ flags |= DETECT_SSL_STATE_CLIENT_HELLO;
+ if (negate)
+ mask |= DETECT_SSL_STATE_CLIENT_HELLO;
+ } else if (strcmp("server_hello", str2) == 0) {
+ flags |= DETECT_SSL_STATE_SERVER_HELLO;
+ if (negate)
+ mask |= DETECT_SSL_STATE_SERVER_HELLO;
+ } else if (strcmp("client_keyx", str2) == 0) {
+ flags |= DETECT_SSL_STATE_CLIENT_KEYX;
+ if (negate)
+ mask |= DETECT_SSL_STATE_CLIENT_KEYX;
+ } else if (strcmp("server_keyx", str2) == 0) {
+ flags |= DETECT_SSL_STATE_SERVER_KEYX;
+ if (negate)
+ mask |= DETECT_SSL_STATE_SERVER_KEYX;
+ } else if (strcmp("unknown", str2) == 0) {
+ flags |= DETECT_SSL_STATE_UNKNOWN;
+ if (negate)
+ mask |= DETECT_SSL_STATE_UNKNOWN;
+ } else {
+ SCLogError("Found invalid option \"%s\" "
+ "in ssl_state keyword.",
+ str2);
+ pcre2_match_data_free(match2);
+ goto error;
+ }
+
+ pcre2len = sizeof(str2);
+ res = pcre2_substring_copy_bynumber(match2, 3, (PCRE2_UCHAR8 *)str2, &pcre2len);
+ if (res < 0) {
+ SCLogError("pcre2_substring_copy_bynumber failed");
+ pcre2_match_data_free(match2);
+ goto error;
+ }
+
+ memcpy(str1, str2, sizeof(str1));
+ pcre2_match_data_free(match2);
+ }
+
+ if ( (ssd = SCMalloc(sizeof(DetectSslStateData))) == NULL) {
+ goto error;
+ }
+ ssd->flags = flags;
+ ssd->mask = mask;
+
+ pcre2_match_data_free(match);
+ return ssd;
+
+error:
+ if (match) {
+ pcre2_match_data_free(match);
+ }
+ return NULL;
+}
+
+ /**
+ * \internal
+ * \brief Setup function for ssl_state keyword.
+ *
+ * \param de_ctx Pointer to the Detection Engine Context.
+ * \param s Pointer to the Current Signature
+ * \param arg String holding the arg.
+ *
+ * \retval 0 On success.
+ * \retval -1 On failure.
+ */
+static int DetectSslStateSetup(DetectEngineCtx *de_ctx, Signature *s, const char *arg)
+{
+ DetectSslStateData *ssd = NULL;
+ SigMatch *sm = NULL;
+
+ if (DetectSignatureSetAppProto(s, ALPROTO_TLS) != 0)
+ return -1;
+
+ ssd = DetectSslStateParse(arg);
+ if (ssd == NULL)
+ goto error;
+
+ sm = SigMatchAlloc();
+ if (sm == NULL)
+ goto error;
+
+ sm->type = DETECT_AL_SSL_STATE;
+ sm->ctx = (SigMatchCtx*)ssd;
+
+ SigMatchAppendSMToList(s, sm, g_tls_generic_list_id);
+ return 0;
+
+error:
+ if (ssd != NULL)
+ DetectSslStateFree(de_ctx, ssd);
+ if (sm != NULL)
+ SCFree(sm);
+ return -1;
+}
+
+/**
+ * \brief Free memory associated with DetectSslStateData.
+ *
+ * \param ptr pointer to the data to be freed.
+ */
+static void DetectSslStateFree(DetectEngineCtx *de_ctx, void *ptr)
+{
+ if (ptr != NULL)
+ SCFree(ptr);
+
+ return;
+}
+
+#ifdef UNITTESTS
+#include "tests/detect-ssl-state.c"
+#endif