Adding upstream version 4.2.2.upstream/4.2.2

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 447 insertions, 0 deletions

diff --git a/epan/dissectors/packet-syslog.c b/epan/dissectors/packet-syslog.c
new file mode 100644
index 0000000..b8645ff
--- /dev/null
+++ b/epan/dissectors/packet-syslog.c
@@ -0,0 +1,447 @@
+/* packet-syslog.c
+ * Routines for syslog message dissection
+ *
+ * Copyright 2000, Gerald Combs <gerald[AT]wireshark.org>
+ *
+ * Support for passing SS7 MSUs (from the Cisco ITP Packet Logging
+ * facility) to the MTP3 dissector by Abhik Sarkar <sarkar.abhik[AT]gmail.com>
+ * with some rework by Jeff Morriss <jeff.morriss.ws [AT] gmail.com>
+ *
+ * Wireshark - Network traffic analyzer
+ * By Gerald Combs <gerald[AT]wireshark.org>
+ * Copyright 1998 Gerald Combs
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+
+#include "config.h"
+
+
+#include <epan/packet.h>
+#include <epan/strutil.h>
+
+#include "packet-syslog.h"
+#include "packet-acdr.h"
+
+#define UDP_PORT_SYSLOG 514
+
+#define PRIORITY_MASK 0x0007  /* 0000 0111 */
+#define FACILITY_MASK 0x03f8  /* 1111 1000 */
+
+void proto_reg_handoff_syslog(void);
+void proto_register_syslog(void);
+
+/* The maximum number if priority digits to read in. */
+#define MAX_DIGITS 3
+
+static const value_string short_level_vals[] = {
+  { LEVEL_EMERG,        "EMERG" },
+  { LEVEL_ALERT,        "ALERT" },
+  { LEVEL_CRIT,         "CRIT" },
+  { LEVEL_ERR,          "ERR" },
+  { LEVEL_WARNING,      "WARNING" },
+  { LEVEL_NOTICE,       "NOTICE" },
+  { LEVEL_INFO,         "INFO" },
+  { LEVEL_DEBUG,        "DEBUG" },
+  { 0, NULL }
+};
+
+static const value_string short_facility_vals[] = {
+  { FAC_KERN,           "KERN" },
+  { FAC_USER,           "USER" },
+  { FAC_MAIL,           "MAIL" },
+  { FAC_DAEMON,         "DAEMON" },
+  { FAC_AUTH,           "AUTH" },
+  { FAC_SYSLOG,         "SYSLOG" },
+  { FAC_LPR,            "LPR" },
+  { FAC_NEWS,           "NEWS" },
+  { FAC_UUCP,           "UUCP" },
+  { FAC_CRON,           "CRON" },       /* The BSDs, Linux, and others */
+  { FAC_AUTHPRIV,       "AUTHPRIV" },
+  { FAC_FTP,            "FTP" },
+  { FAC_NTP,            "NTP" },
+  { FAC_LOGAUDIT,       "LOGAUDIT" },
+  { FAC_LOGALERT,       "LOGALERT" },
+  { FAC_CRON_SOL,       "CRON" },       /* Solaris */
+  { FAC_LOCAL0,         "LOCAL0" },
+  { FAC_LOCAL1,         "LOCAL1" },
+  { FAC_LOCAL2,         "LOCAL2" },
+  { FAC_LOCAL3,         "LOCAL3" },
+  { FAC_LOCAL4,         "LOCAL4" },
+  { FAC_LOCAL5,         "LOCAL5" },
+  { FAC_LOCAL6,         "LOCAL6" },
+  { FAC_LOCAL7,         "LOCAL7" },
+  { 0, NULL }
+};
+
+static gint proto_syslog = -1;
+static gint hf_syslog_level = -1;
+static gint hf_syslog_facility = -1;
+static gint hf_syslog_msg = -1;
+static gint hf_syslog_msu_present = -1;
+static gint hf_syslog_version = -1;
+static gint hf_syslog_timestamp = -1;
+static gint hf_syslog_timestamp_old = -1;
+static gint hf_syslog_hostname = -1;
+static gint hf_syslog_appname = -1;
+static gint hf_syslog_procid = -1;
+static gint hf_syslog_msgid = -1;
+static gint hf_syslog_msgid_utf8 = -1;
+static gint hf_syslog_msgid_bom = -1;
+
+static gint ett_syslog = -1;
+static gint ett_syslog_msg = -1;
+
+static dissector_handle_t syslog_handle;
+
+static dissector_handle_t mtp_handle;
+
+/*  The Cisco ITP's packet logging facility allows selected (SS7) MSUs to be
+ *  to be encapsulated in syslog UDP datagrams and sent to a monitoring tool.
+ *  However, no actual tool to monitor/decode the MSUs is provided. The aim
+ *  of this routine is to extract the hex dump of the MSU from the syslog
+ *  packet so that it can be passed on to the mtp3 dissector for decoding.
+ */
+static tvbuff_t *
+mtp3_msu_present(tvbuff_t *tvb, packet_info *pinfo, gint fac, gint level, const char *msg_str, gint chars_truncated)
+{
+  size_t nbytes;
+  size_t len;
+  gchar **split_string, *msu_hex_dump;
+  tvbuff_t *mtp3_tvb = NULL;
+  guint8 *byte_array;
+
+  /*  In the sample capture I have, all MSUs are LOCAL0.DEBUG.
+   *  Try to optimize this routine for most syslog users by short-cutting
+   *  out here.
+   */
+  if (!(fac == FAC_LOCAL0 && level == LEVEL_DEBUG))
+    return NULL;
+
+  if (strstr(msg_str, "msu=") == NULL)
+    return NULL;
+
+  split_string = g_strsplit(msg_str, "msu=", 2);
+  msu_hex_dump = split_string[1];
+
+  if (msu_hex_dump && (len = strlen(msu_hex_dump))) {
+
+    /*  convert_string_to_hex() will return NULL if it gets an incomplete
+     *  byte.  If we have an odd string length then chop off the remaining
+     *  nibble so we can get at least a partial MSU (chances are the
+     *  subdissector will except out, of course).
+     */
+    if (len % 2)
+        msu_hex_dump[len - 1] = '\0';
+
+    byte_array = convert_string_to_hex(msu_hex_dump, &nbytes);
+
+    if (byte_array) {
+        mtp3_tvb = tvb_new_child_real_data(tvb, byte_array, (guint)nbytes,
+                                           (guint)nbytes + chars_truncated / 2);
+        tvb_set_free_cb(mtp3_tvb, g_free);
+        /* ...and add the encapsulated MSU as a new data source so that it gets
+         * its own tab in the packet bytes pane.
+         */
+        add_new_data_source(pinfo, mtp3_tvb, "Encapsulated MSU");
+    }
+  }
+
+  g_strfreev(split_string);
+
+  return(mtp3_tvb);
+}
+
+static gboolean dissect_syslog_info(proto_tree* tree, tvbuff_t* tvb, guint* offset, gint hfindex)
+{
+  gint end_offset = tvb_find_guint8(tvb, *offset, -1, ' ');
+  if (end_offset == -1)
+    return FALSE;
+  proto_tree_add_item(tree, hfindex, tvb, *offset, end_offset - *offset, ENC_NA);
+  *offset = end_offset + 1;
+  return TRUE;
+}
+
+/* Dissect message as defined in RFC5424 */
+static void
+dissect_syslog_message(proto_tree* tree, tvbuff_t* tvb, guint offset)
+{
+  gint end_offset;
+
+  if (!dissect_syslog_info(tree, tvb, &offset, hf_syslog_version))
+    return;
+
+  end_offset = tvb_find_guint8(tvb, offset, -1, ' ');
+  if (end_offset == -1)
+    return;
+  if ((guint)end_offset != offset) {
+    /* do not call proto_tree_add_time_item with a length of 0 */
+    proto_tree_add_time_item(tree, hf_syslog_timestamp, tvb, offset, end_offset - offset, ENC_ISO_8601_DATE_TIME,
+      NULL, NULL, NULL);
+  }
+  offset = end_offset + 1;
+
+  if (!dissect_syslog_info(tree, tvb, &offset, hf_syslog_hostname))
+    return;
+  if (!dissect_syslog_info(tree, tvb, &offset, hf_syslog_appname))
+    return;
+  if (!dissect_syslog_info(tree, tvb, &offset, hf_syslog_procid))
+    return;
+  if (tvb_get_guint24(tvb, offset, ENC_BIG_ENDIAN) == 0xefbbbf) {
+    proto_tree_add_item(tree, hf_syslog_msgid_bom, tvb, offset, 3, ENC_BIG_ENDIAN);
+    offset += 3;
+    proto_tree_add_item(tree, hf_syslog_msgid_utf8, tvb, offset, tvb_reported_length_remaining(tvb, offset), ENC_UTF_8);
+  } else {
+    proto_tree_add_item(tree, hf_syslog_msgid, tvb, offset, tvb_reported_length_remaining(tvb, offset), ENC_ASCII);
+  }
+}
+
+/* Dissect message as defined in RFC3164 */
+static void
+dissect_rfc3164_syslog_message(proto_tree* tree, tvbuff_t* tvb, guint offset)
+{
+  guint tvb_offset = 0;
+
+  /* Simple check if the first 16 bytes look like TIMESTAMP "Mmm dd hh:mm:ss"
+   * by checking for spaces and colons. Otherwise return without processing
+   * the message. */
+  if (tvb_get_guint8(tvb, offset + 3) == ' ' && tvb_get_guint8(tvb, offset + 6) == ' ' &&
+        tvb_get_guint8(tvb, offset + 9) == ':' && tvb_get_guint8(tvb, offset + 12) == ':' &&
+        tvb_get_guint8(tvb, offset + 15) == ' ') {
+    proto_tree_add_item(tree, hf_syslog_timestamp_old, tvb, offset, 15, ENC_ASCII);
+    offset += 16;
+  } else {
+    return;
+  }
+
+  if (!dissect_syslog_info(tree, tvb, &offset, hf_syslog_hostname))
+    return;
+  for (tvb_offset=offset; tvb_offset < offset+32; tvb_offset++){
+    guint8 octet;
+    octet = tvb_get_guint8(tvb, tvb_offset);
+    if (!g_ascii_isalnum(octet)){
+      proto_tree_add_item(tree, hf_syslog_procid, tvb, offset, tvb_offset - offset, ENC_ASCII);
+      offset = tvb_offset;
+      break;
+    }
+  }
+  proto_tree_add_item(tree, hf_syslog_msgid, tvb, offset, tvb_reported_length_remaining(tvb, offset), ENC_ASCII);
+}
+
+/* The message format is defined in RFC 3164 */
+static int
+dissect_syslog(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, void* data _U_)
+{
+  gint pri = -1, lev = -1, fac = -1;
+  gint msg_off = 0, msg_len, reported_msg_len;
+  proto_item *ti;
+  proto_tree *syslog_tree;
+  proto_tree *syslog_message_tree;
+  const char *msg_str;
+  tvbuff_t *mtp3_tvb;
+
+  col_set_str(pinfo->cinfo, COL_PROTOCOL, "Syslog");
+  col_clear(pinfo->cinfo, COL_INFO);
+
+  if (tvb_get_guint8(tvb, msg_off) == '<') {
+    /* A facility and level follow. */
+    msg_off++;
+    pri = 0;
+    while (tvb_bytes_exist(tvb, msg_off, 1) &&
+           g_ascii_isdigit(tvb_get_guint8(tvb, msg_off)) && msg_off <= MAX_DIGITS) {
+      pri = pri * 10 + (tvb_get_guint8(tvb, msg_off) - '0');
+      msg_off++;
+    }
+    if (tvb_get_guint8(tvb, msg_off) == '>')
+      msg_off++;
+    fac = (pri & FACILITY_MASK) >> 3;
+    lev = pri & PRIORITY_MASK;
+  }
+
+  msg_len = tvb_ensure_captured_length_remaining(tvb, msg_off);
+  msg_str = tvb_format_text(pinfo->pool, tvb, msg_off, msg_len);
+  reported_msg_len = tvb_reported_length_remaining(tvb, msg_off);
+
+  mtp3_tvb = mtp3_msu_present(tvb, pinfo, fac, lev, msg_str,
+                              (reported_msg_len - msg_len));
+
+  if (mtp3_tvb == NULL) {
+    if (pri >= 0) {
+      col_add_fstr(pinfo->cinfo, COL_INFO, "%s.%s: %s",
+        val_to_str_const(fac, short_facility_vals, "UNKNOWN"),
+        val_to_str_const(lev, short_level_vals, "UNKNOWN"), msg_str);
+    } else {
+      col_add_str(pinfo->cinfo, COL_INFO, msg_str);
+    }
+  }
+
+  if (tree) {
+    if (pri >= 0) {
+      ti = proto_tree_add_protocol_format(tree, proto_syslog, tvb, 0, -1,
+        "Syslog message: %s.%s: %s",
+        val_to_str_const(fac, short_facility_vals, "UNKNOWN"),
+        val_to_str_const(lev, short_level_vals, "UNKNOWN"), msg_str);
+    } else {
+      ti = proto_tree_add_protocol_format(tree, proto_syslog, tvb, 0, -1,
+        "Syslog message: (unknown): %s", msg_str);
+    }
+    syslog_tree = proto_item_add_subtree(ti, ett_syslog);
+    if (pri >= 0) {
+      proto_tree_add_uint(syslog_tree, hf_syslog_facility, tvb, 0,
+        msg_off, pri);
+      proto_tree_add_uint(syslog_tree, hf_syslog_level, tvb, 0,
+        msg_off, pri);
+    }
+    ti = proto_tree_add_item(syslog_tree, hf_syslog_msg, tvb, msg_off,
+      msg_len, ENC_UTF_8);
+    syslog_message_tree = proto_item_add_subtree(ti, ett_syslog_msg);
+
+    /* RFC5424 defines a version field which is currently defined as '1'
+     * followed by a space (0x3120). Otherwise the message is probable
+     * a RFC3164 message.
+     */
+    if (msg_len > 2 && tvb_get_ntohs(tvb, msg_off) == 0x3120) {
+      dissect_syslog_message(syslog_message_tree, tvb, msg_off);
+    } else if ( msg_len > 15) {
+      dissect_rfc3164_syslog_message(syslog_message_tree, tvb, msg_off);
+    }
+
+    if (mtp3_tvb) {
+      proto_item *mtp3_item;
+      mtp3_item = proto_tree_add_boolean(syslog_tree, hf_syslog_msu_present,
+                                         tvb, msg_off, msg_len, TRUE);
+      proto_item_set_generated(mtp3_item);
+    }
+  }
+
+  /* Call MTP dissector if encapsulated MSU was found... */
+  if (mtp3_tvb) {
+    call_dissector(mtp_handle, mtp3_tvb, pinfo, tree);
+  }
+
+  return tvb_captured_length(tvb);
+}
+
+/* Register the protocol with Wireshark */
+void proto_register_syslog(void)
+{
+
+  /* Setup list of header fields */
+  static hf_register_info hf[] = {
+    { &hf_syslog_facility,
+      { "Facility",           "syslog.facility",
+        FT_UINT8, BASE_DEC, VALS(syslog_facility_vals), FACILITY_MASK,
+        "Message facility", HFILL }
+    },
+    { &hf_syslog_level,
+      { "Level",              "syslog.level",
+        FT_UINT8, BASE_DEC, VALS(syslog_level_vals), PRIORITY_MASK,
+        "Message level", HFILL }
+    },
+    { &hf_syslog_msg,
+      { "Message",            "syslog.msg",
+        FT_STRING, BASE_NONE, NULL, 0x0,
+        "Message Text", HFILL }
+    },
+    { &hf_syslog_msu_present,
+      { "SS7 MSU present",    "syslog.msu_present",
+        FT_BOOLEAN, BASE_NONE, NULL, 0x0,
+        "True if an SS7 MSU was detected in the syslog message",
+        HFILL }
+    },
+    { &hf_syslog_version,
+      { "Syslog version", "syslog.version",
+        FT_STRING, BASE_NONE, NULL, 0x0,
+        NULL,
+        HFILL }
+    },
+    { &hf_syslog_timestamp,
+      { "Syslog timestamp", "syslog.timestamp",
+        FT_ABSOLUTE_TIME, ABSOLUTE_TIME_UTC, NULL, 0x0,
+        NULL,
+        HFILL }
+    },
+    { &hf_syslog_timestamp_old,
+      { "Syslog timestamp (RFC3164)", "syslog.timestamp_rfc3164",
+        FT_STRING, ENC_ASCII, NULL, 0x0,
+        NULL,
+        HFILL }
+    },
+    { &hf_syslog_hostname,
+      { "Syslog hostname", "syslog.hostname",
+        FT_STRING, ENC_ASCII, NULL, 0x0,
+        NULL,
+        HFILL }
+    },
+    { &hf_syslog_appname,
+      { "Syslog app name", "syslog.appname",
+        FT_STRING, ENC_ASCII, NULL, 0x0,
+        "The name of the app that generated this message",
+        HFILL }
+    },
+    { &hf_syslog_procid,
+      { "Syslog process id", "syslog.procid",
+        FT_STRING, ENC_ASCII, NULL, 0x0,
+        NULL,
+        HFILL }
+    },
+    { &hf_syslog_msgid,
+      { "Syslog message id", "syslog.msgid",
+        FT_STRING, ENC_ASCII, NULL, 0x0,
+        NULL,
+        HFILL }
+    },
+    { &hf_syslog_msgid_utf8,
+      { "Syslog message id", "syslog.msgid",
+        FT_STRING, BASE_NONE, NULL, 0x0,
+        NULL,
+        HFILL }
+    },
+    { &hf_syslog_msgid_bom,
+      { "Syslog BOM", "syslog.msgid.bom",
+        FT_UINT24, BASE_HEX, NULL, 0x0,
+        NULL,
+        HFILL }
+    }
+  };
+
+  /* Setup protocol subtree array */
+  static gint *ett[] = {
+    &ett_syslog,
+    &ett_syslog_msg
+  };
+
+  /* Register the protocol name and description */
+  proto_syslog = proto_register_protocol("Syslog message", "Syslog", "syslog");
+
+  /* Required function calls to register the header fields and subtrees used */
+  proto_register_field_array(proto_syslog, hf, array_length(hf));
+  proto_register_subtree_array(ett, array_length(ett));
+
+  syslog_handle = register_dissector("syslog", dissect_syslog, proto_syslog);
+}
+
+void
+proto_reg_handoff_syslog(void)
+{
+  dissector_add_uint_with_preference("udp.port", UDP_PORT_SYSLOG, syslog_handle);
+  dissector_add_for_decode_as_with_preference("tcp.port", syslog_handle);
+
+  dissector_add_uint("acdr.media_type", ACDR_Info, syslog_handle);
+
+  /* Find the mtp3 dissector */
+  mtp_handle = find_dissector_add_dependency("mtp3", proto_syslog);
+}
+
+/*
+ * Editor modelines  -  https://www.wireshark.org/tools/modelines.html
+ *
+ * Local Variables:
+ * c-basic-offset: 2
+ * tab-width: 8
+ * indent-tabs-mode: nil
+ * End:
+ *
+ * ex: set shiftwidth=2 tabstop=8 expandtab:
+ * :indentSize=2:tabSize=8:noTabs=true:
+ */