lua: SSH support

Support SSH in lua detection scripts (Feature #1569).

src/Makefile.am

@@ -356,6 +356,7 @@ util-lua-common.c util-lua-common.h \
 util-lua-dns.c util-lua-dns.h \
 util-lua-http.c util-lua-http.h \
 util-lua-tls.c util-lua-tls.h \
+util-lua-ssh.c util-lua-ssh.h \
 util-magic.c util-magic.h \
 util-memcmp.c util-memcmp.h \
 util-memcpy.h \

src/detect-lua-extensions.c

@@ -67,6 +67,7 @@
 #include "util-lua-http.h"
 #include "util-lua-dns.h"
 #include "util-lua-tls.h"
+#include "util-lua-ssh.h"
 
 static const char luaext_key_ld[] = "suricata:luajitdata";
 static const char luaext_key_det_ctx[] = "suricata:det_ctx";
@@ -619,6 +620,7 @@ int LuaRegisterExtensions(lua_State *lua_state)
     LuaRegisterHttpFunctions(lua_state);
     LuaRegisterDnsFunctions(lua_state);
     LuaRegisterTlsFunctions(lua_state);
+    LuaRegisterSshFunctions(lua_state);
     return 0;
 }
 

src/detect-lua.c

@@ -166,6 +166,8 @@ void DetectLuaRegister(void)
 
 #define DATATYPE_TLS                        (1<<18)
 
+#define DATATYPE_SSH                        (1<<19)
+
 #ifdef HAVE_LUAJIT
 static void *LuaStatePoolAlloc(void)
 {
@@ -1008,6 +1010,12 @@ static int DetectLuaSetupPrime(DetectEngineCtx *de_ctx, DetectLuaData *ld)
 
             ld->flags |= DATATYPE_TLS;
 
+        } else if (strncmp(k, "ssh", 3) == 0 && strcmp(v, "true") == 0) {
+
+            ld->alproto = ALPROTO_SSH;
+
+            ld->flags |= DATATYPE_SSH;
+
         } else {
             SCLogError(SC_ERR_LUA_ERROR, "unsupported data type %s", k);
             goto error;
@@ -1105,6 +1113,8 @@ static int DetectLuaSetup (DetectEngineCtx *de_ctx, Signature *s, char *str)
         }
     } else if (luajit->alproto == ALPROTO_TLS) {
         SigMatchAppendSMToList(s, sm, DETECT_SM_LIST_AMATCH);
+    } else if (luajit->alproto == ALPROTO_SSH) {
+        SigMatchAppendSMToList(s, sm, DETECT_SM_LIST_AMATCH);
     } else {
         SCLogError(SC_ERR_LUA_ERROR, "luajit can't be used with protocol %s",
                    AppLayerGetProtoName(luajit->alproto));

src/util-lua-ssh.c

@@ -0,0 +1,227 @@
+/* Copyright (C) 2014 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 Mats Klepsland <mats.klepsland@gmail.com>
+ *
+ */
+
+#include "suricata-common.h"
+#include "debug.h"
+#include "detect.h"
+#include "pkt-var.h"
+#include "conf.h"
+
+#include "threads.h"
+#include "threadvars.h"
+#include "tm-threads.h"
+
+#include "util-print.h"
+#include "util-unittest.h"
+
+#include "util-debug.h"
+
+#include "output.h"
+#include "app-layer.h"
+#include "app-layer-parser.h"
+#include "app-layer-ssh.h"
+#include "util-privs.h"
+#include "util-buffer.h"
+#include "util-proto-name.h"
+#include "util-logopenfile.h"
+#include "util-time.h"
+
+#ifdef HAVE_LUA
+
+#include <lua.h>
+#include <lualib.h>
+#include <lauxlib.h>
+
+#include "util-lua.h"
+#include "util-lua-common.h"
+
+static int GetServerProtoVersion(lua_State *luastate, const Flow *f)
+{
+    void *state = FlowGetAppState(f);
+    if (state == NULL)
+        return LuaCallbackError(luastate, "error: no app layer state");
+
+    SshState *ssh_state = (SshState *)state;
+
+    if (ssh_state->srv_hdr.proto_version == NULL)
+        return LuaCallbackError(luastate, "error: no server proto version");
+
+    return LuaPushStringBuffer(luastate, ssh_state->srv_hdr.proto_version,
+                               strlen((char *)ssh_state->srv_hdr.proto_version));
+}
+
+static int SshGetServerProtoVersion(lua_State *luastate)
+{
+    int r;
+
+    if (!(LuaStateNeedProto(luastate, ALPROTO_SSH)))
+        return LuaCallbackError(luastate, "error: protocol not ssh");
+
+    int lock_hint = 0;
+    Flow *f = LuaStateGetFlow(luastate, &lock_hint);
+    if (f == NULL)
+        return LuaCallbackError(luastate, "internal error: no flow");
+
+    if (lock_hint == LUA_FLOW_NOT_LOCKED_BY_PARENT) {
+        FLOWLOCK_RDLOCK(f);
+        r = GetServerProtoVersion(luastate, f);
+        FLOWLOCK_UNLOCK(f);
+    } else {
+        r = GetServerProtoVersion(luastate, f);
+    }
+    return r;
+}
+
+static int GetServerSoftwareVersion(lua_State *luastate, const Flow *f)
+{
+    void *state = FlowGetAppState(f);
+    if (state == NULL)
+        return LuaCallbackError(luastate, "error: no app layer state");
+
+    SshState *ssh_state = (SshState *)state;
+
+    if (ssh_state->srv_hdr.software_version == NULL)
+        return LuaCallbackError(luastate, "error: no server software version");
+
+    return LuaPushStringBuffer(luastate, ssh_state->srv_hdr.software_version,
+                               strlen((char *)ssh_state->srv_hdr.software_version));
+}
+
+static int SshGetServerSoftwareVersion(lua_State *luastate)
+{
+    int r;
+
+    if (!(LuaStateNeedProto(luastate, ALPROTO_SSH)))
+        return LuaCallbackError(luastate, "error: protocol not ssh");
+
+    int lock_hint = 0;
+    Flow *f = LuaStateGetFlow(luastate, &lock_hint);
+    if (f == NULL)
+        return LuaCallbackError(luastate, "internal error: no flow");
+
+    if (lock_hint == LUA_FLOW_NOT_LOCKED_BY_PARENT) {
+        FLOWLOCK_RDLOCK(f);
+        r = GetServerSoftwareVersion(luastate, f);
+        FLOWLOCK_UNLOCK(f);
+    } else {
+        r = GetServerSoftwareVersion(luastate, f);
+    }
+    return r;
+}
+
+static int GetClientProtoVersion(lua_State *luastate, const Flow *f)
+{
+    void *state = FlowGetAppState(f);
+    if (state == NULL)
+        return LuaCallbackError(luastate, "error: no app layer state");
+
+    SshState *ssh_state = (SshState *)state;
+
+    if (ssh_state->cli_hdr.proto_version == NULL)
+        return LuaCallbackError(luastate, "error: no client proto version");
+
+    return LuaPushStringBuffer(luastate, ssh_state->cli_hdr.proto_version,
+                               strlen((char *)ssh_state->cli_hdr.proto_version));
+}
+
+static int SshGetClientProtoVersion(lua_State *luastate)
+{
+    int r;
+
+    if (!(LuaStateNeedProto(luastate, ALPROTO_SSH)))
+        return LuaCallbackError(luastate, "error: protocol not ssh");
+
+    int lock_hint = 0;
+    Flow *f = LuaStateGetFlow(luastate, &lock_hint);
+    if (f == NULL)
+        return LuaCallbackError(luastate, "internal error: no flow");
+
+    if (lock_hint == LUA_FLOW_NOT_LOCKED_BY_PARENT) {
+        FLOWLOCK_RDLOCK(f);
+        r = GetClientProtoVersion(luastate, f);
+        FLOWLOCK_UNLOCK(f);
+    } else {
+        r = GetClientProtoVersion(luastate, f);
+    }
+    return r;
+}
+
+static int GetClientSoftwareVersion(lua_State *luastate, const Flow *f)
+{
+    void *state = FlowGetAppState(f);
+    if (state == NULL)
+        return LuaCallbackError(luastate, "error: no app layer state");
+
+    SshState *ssh_state = (SshState *)state;
+
+    if (ssh_state->cli_hdr.software_version == NULL)
+        return LuaCallbackError(luastate, "error: no client software version");
+
+    return LuaPushStringBuffer(luastate, ssh_state->cli_hdr.software_version,
+                               strlen((char *)ssh_state->cli_hdr.software_version));
+}
+
+static int SshGetClientSoftwareVersion(lua_State *luastate)
+{
+    int r;
+
+    if (!(LuaStateNeedProto(luastate, ALPROTO_SSH)))
+        return LuaCallbackError(luastate, "error: protocol not ssh");
+
+    int lock_hint = 0;
+    Flow *f = LuaStateGetFlow(luastate, &lock_hint);
+    if (f == NULL)
+        return LuaCallbackError(luastate, "internal error: no flow");
+
+    if (lock_hint == LUA_FLOW_NOT_LOCKED_BY_PARENT) {
+        FLOWLOCK_RDLOCK(f);
+        r = GetClientSoftwareVersion(luastate, f);
+        FLOWLOCK_UNLOCK(f);
+    } else {
+        r = GetClientSoftwareVersion(luastate, f);
+    }
+    return r;
+}
+
+/** \brief register ssh lua extensions in a luastate */
+int LuaRegisterSshFunctions(lua_State *luastate)
+{
+    /* registration of the callbacks */
+    lua_pushcfunction(luastate, SshGetServerProtoVersion);
+    lua_setglobal(luastate, "SshGetServerProtoVersion");
+
+    lua_pushcfunction(luastate, SshGetServerSoftwareVersion);
+    lua_setglobal(luastate, "SshGetServerSoftwareVersion");
+
+    lua_pushcfunction(luastate, SshGetClientProtoVersion);
+    lua_setglobal(luastate, "SshGetClientProtoVersion");
+
+    lua_pushcfunction(luastate, SshGetClientSoftwareVersion);
+    lua_setglobal(luastate, "SshGetClientSoftwareVersion");
+
+    return 0;
+}
+
+#endif /* HAVE_LUA */

src/util-lua-ssh.h

@@ -0,0 +1,33 @@
+/* Copyright (C) 2015 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 Mats Klepsland <mats.klepsland@gmail.com>
+ */
+
+#ifndef __UTIL_LUA_SSH_H__
+#define __UTIL_LUA_SSH_H__
+
+#ifdef HAVE_LUA
+
+int LuaRegisterSshFunctions(lua_State *luastate);
+
+#endif /* HAVE_LUA */
+
+#endif /* __UTIL_LUA_SSH_H__ */