BER: get rid of WTAP_FILE_TYPE_SUBTYPE_BER.

Save a copy of the pathname used to open a file in the wtap structure.
This allows the BER file reader to put a pointer to it in the
pseudo-header; it also would allow file readers to attempt to read
"associated" files that have the same name as the file, but with a
different extension.

Instead of having cf_open() special-case BER files, and calling a
routine in the BER dissector to specify the file name to the dissector,
have separate dissectors for "dissect packet payload as BER" and
"dissect a file as BER", and have the latter get the pathname of the
file from the pseudo-header and determine the ASN.1 syntax from that.

(Side-effect - this means that you can now dissect a BER file, and have
the syntax be determined by the file extension, in TShark as well; the
above cf_open() special-casing was *not* done in TShark, so it didn't
work before.  Now the application code doesn't need to do any of that,
so it works in TShark as well as Wireshark.)

5 files changed, 60 insertions, 11 deletions

diff --git a/wiretap/ber.c b/wiretap/ber.c
index c6bdd9c600..789f93993c 100644
--- a/wiretap/ber.c
+++ b/wiretap/ber.c
@@ -22,6 +22,34 @@
 #define BER_UNI_TAG_SEQ 16      /* SEQUENCE, SEQUENCE OF */
 #define BER_UNI_TAG_SET 17      /* SET, SET OF */
 
+static int ber_file_type_subtype = -1;
+
+void register_ber(void);
+
+static gboolean ber_full_file_read(wtap *wth, wtap_rec *rec, Buffer *buf,
+                                   int *err, gchar **err_info,
+                                   gint64 *data_offset)
+{
+  if (!wtap_full_file_read(wth, rec, buf, err, err_info, data_offset))
+    return FALSE;
+
+  /* Pass the file name. */
+  rec->rec_header.packet_header.pseudo_header.ber.pathname = wth->pathname;
+  return TRUE;
+}
+
+static gboolean ber_full_file_seek_read(wtap *wth, gint64 seek_off,
+                                        wtap_rec *rec, Buffer *buf,
+                                        int *err, gchar **err_info)
+{
+  if (!wtap_full_file_seek_read(wth, seek_off, rec, buf, err, err_info))
+    return FALSE;
+
+  /* Pass the file name. */
+  rec->rec_header.packet_header.pseudo_header.ber.pathname = wth->pathname;
+  return TRUE;
+}
+
 wtap_open_return_val ber_open(wtap *wth, int *err, gchar **err_info)
 {
 #define BER_BYTES_TO_CHECK 8
@@ -90,17 +118,34 @@ wtap_open_return_val ber_open(wtap *wth, int *err, gchar **err_info)
   if (file_seek(wth->fh, 0, SEEK_SET, err) == -1)
     return WTAP_OPEN_ERROR;
 
-  wth->file_type_subtype = WTAP_FILE_TYPE_SUBTYPE_BER;
+  wth->file_type_subtype = ber_file_type_subtype;
   wth->file_encap = WTAP_ENCAP_BER;
   wth->snapshot_length = 0;
 
-  wth->subtype_read = wtap_full_file_read;
-  wth->subtype_seek_read = wtap_full_file_seek_read;
+  wth->subtype_read = ber_full_file_read;
+  wth->subtype_seek_read = ber_full_file_seek_read;
   wth->file_tsprec = WTAP_TSPREC_SEC;
 
   return WTAP_OPEN_MINE;
 }
 
+static const struct file_type_subtype_info ber_info = {
+  "ASN.1 Basic Encoding Rules", "ber", NULL, NULL,
+  FALSE, FALSE, 0,
+  NULL, NULL, NULL
+};
+
+void register_ber(void)
+{
+  ber_file_type_subtype = wtap_register_file_type_subtypes(&ber_info);
+
+  /*
+   * Register name for backwards compatibility with the
+   * wtap_filetypes table in Lua.
+   */
+  wtap_register_backwards_compatibility_lua_name("BER", ber_file_type_subtype);
+}
+
 /*
  * Editor modelines  -  https://www.wireshark.org/tools/modelines.html
  *
diff --git a/wiretap/file_access.c b/wiretap/file_access.c
index bc5c0bda21..db93a129a5 100644
--- a/wiretap/file_access.c
+++ b/wiretap/file_access.c
@@ -878,6 +878,7 @@ wtap_open_offline(const char *filename, unsigned int type, int *err, char **err_
 	wth->subtype_sequential_close = NULL;
 	wth->subtype_close = NULL;
 	wth->file_tsprec = WTAP_TSPREC_USEC;
+	wth->pathname = g_strdup(filename);
 	wth->priv = NULL;
 	wth->wslua_data = NULL;
 	wth->shb_hdrs = g_array_new(FALSE, FALSE, sizeof(wtap_block_t));
@@ -1279,12 +1280,7 @@ static const struct file_type_subtype_info file_type_subtype_table_base[] = {
 	/* WTAP_FILE_TYPE_SUBTYPE_IPTRACE_2_0 */
 	{ "AIX iptrace 2.0", "iptrace_2", NULL, NULL,
 	  FALSE, FALSE, 0,
-	  NULL, NULL, NULL },
-
-	/* WTAP_FILE_TYPE_SUBTYPE_BER */
-	{ "ASN.1 Basic Encoding Rules", "ber", NULL, NULL,
-	  FALSE, FALSE, 0,
-	  NULL, NULL, NULL },
+	  NULL, NULL, NULL }
 };
 
 #define N_DUMP_OPEN_TABLE_BASE_ENTRIES	(sizeof(file_type_subtype_table_base) / sizeof(struct file_type_subtype_info))
@@ -2829,8 +2825,6 @@ wtap_register_backwards_compatibility_lua_name(const char *name, int ft)
 		    WTAP_FILE_TYPE_SUBTYPE_IPTRACE_1_0);
 		wtap_register_backwards_compatibility_lua_name("IPTRACE_2_0",
 		    WTAP_FILE_TYPE_SUBTYPE_IPTRACE_2_0);
-		wtap_register_backwards_compatibility_lua_name("BER",
-		    WTAP_FILE_TYPE_SUBTYPE_BER);
 	}
 	entry.name = name;
 	entry.ft = ft;
diff --git a/wiretap/wtap-int.h b/wiretap/wtap-int.h
index 8af29422b2..43d612f1be 100644
--- a/wiretap/wtap-int.h
+++ b/wiretap/wtap-int.h
@@ -48,6 +48,8 @@ struct wtap {
     GArray                      *nrb_hdrs;              /**< holds the Name Res Block's comment/custom_opts, or NULL */
     GArray                      *dsbs;                  /**< An array of DSBs (of type wtap_block_t), or NULL if not supported. */
 
+    char                        *pathname;              /**< File pathname; might just be "-" */
+
     void                        *priv;          /* this one holds per-file state and is free'd automatically by wtap_close() */
     void                        *wslua_data;    /* this one holds wslua state info and is not free'd */
 
diff --git a/wiretap/wtap.c b/wiretap/wtap.c
index f1d8868bf7..26dab87158 100644
--- a/wiretap/wtap.c
+++ b/wiretap/wtap.c
@@ -1441,6 +1441,8 @@ wtap_close(wtap *wth)
 
 	g_free(wth->priv);
 
+	g_free(wth->pathname);
+
 	if (wth->fast_seek != NULL) {
 		g_ptr_array_foreach(wth->fast_seek, g_fast_seek_item_free, NULL);
 		g_ptr_array_free(wth->fast_seek, TRUE);
diff --git a/wiretap/wtap.h b/wiretap/wtap.h
index 40006d829f..6d345d2cbc 100644
--- a/wiretap/wtap.h
+++ b/wiretap/wtap.h
@@ -1133,6 +1133,11 @@ struct netmon_phdr {
     } subheader;
 };
 
+/* File "pseudo-header" for BER data files. */
+struct ber_phdr {
+    const char *pathname;   /* Path name of file. */
+};
+
 union wtap_pseudo_header {
     struct eth_phdr     eth;
     struct dte_dce_phdr dte_dce;
@@ -1160,6 +1165,7 @@ union wtap_pseudo_header {
     struct llcp_phdr    llcp;
     struct logcat_phdr  logcat;
     struct netmon_phdr  netmon;
+    struct ber_phdr     ber;
 };
 
 /*