epan/export_object.c

   1 /* export_object.c
   2  * GUI independent helper routines common to all export object taps.
   3  *
   4  * Wireshark - Network traffic analyzer
   5  * By Gerald Combs <gerald@wireshark.org>
   6  * Copyright 1998 Gerald Combs
   7  *
   8  * SPDX-License-Identifier: GPL-2.0-or-later
   9  */
  10
  11 #include "config.h"
  12
  13 #include <string.h>
  14
  15 #include "proto.h"
  16 #include "packet_info.h"
  17 #include "export_object.h"
  18
  19 struct register_eo {
  20     int proto_id;                        /* protocol id (0-indexed) */
  21     const char* tap_listen_str;          /* string used in register_tap_listener (NULL to use protocol name) */
  22     tap_packet_cb eo_func;               /* function to be called for new incoming packets for SRT */
  23     export_object_gui_reset_cb reset_cb; /* function to parse parameters of optional arguments of tap string */
  24 };
  25
  26 static wmem_tree_t *registered_eo_tables;
  27
  28 int
  29 register_export_object(const int proto_id, tap_packet_cb export_packet_func, export_object_gui_reset_cb reset_cb)
  30 {
  31     register_eo_t *table;
  32     DISSECTOR_ASSERT(export_packet_func);
  33
  34     table = wmem_new(wmem_epan_scope(), register_eo_t);
  35
  36     table->proto_id      = proto_id;
  37     table->tap_listen_str = wmem_strdup_printf(wmem_epan_scope(), "%s_eo", proto_get_protocol_filter_name(proto_id));
  38     table->eo_func = export_packet_func;
  39     table->reset_cb = reset_cb;
  40
  41     if (registered_eo_tables == NULL)
  42         registered_eo_tables = wmem_tree_new(wmem_epan_scope());
  43
  44     wmem_tree_insert_string(registered_eo_tables, proto_get_protocol_filter_name(proto_id), table, 0);
  45     return register_tap(table->tap_listen_str);
  46 }
  47
  48 int get_eo_proto_id(register_eo_t* eo)
  49 {
  50     if (!eo) {
  51         return -1;
  52     }
  53     return eo->proto_id;
  54 }
  55
  56 const char* get_eo_tap_listener_name(register_eo_t* eo)
  57 {
  58     return eo->tap_listen_str;
  59 }
  60
  61 tap_packet_cb get_eo_packet_func(register_eo_t* eo)
  62 {
  63     return eo->eo_func;
  64 }
  65
  66 export_object_gui_reset_cb get_eo_reset_func(register_eo_t* eo)
  67 {
  68     return eo->reset_cb;
  69 }
  70
  71 register_eo_t* get_eo_by_name(const char* name)
  72 {
  73     return (register_eo_t*)wmem_tree_lookup_string(registered_eo_tables, name, 0);
  74 }
  75
  76 void eo_iterate_tables(wmem_foreach_func func, void *user_data)
  77 {
  78     wmem_tree_foreach(registered_eo_tables, func, user_data);
  79 }
  80
  81 static GString *eo_rename(GString *gstr, size_t maxlen, int dupn)
  82 {
  83     GString *gstr_tmp;
  84     char *tmp_ptr;
  85     GString *ext_str = NULL;
  86
  87     gstr_tmp = g_string_new("");
  88     if (dupn != 0) {
  89         g_string_append_printf (gstr_tmp, "(%d)", dupn);
  90     }
  91     if ( (tmp_ptr = strrchr(gstr->str, '.')) != NULL && ((ext_str = g_string_new(tmp_ptr))->len + strlen(gstr_tmp->str) < maxlen) ) {
  92         /* Retain the extension */
  93         gstr = g_string_truncate(gstr, gstr->len - ext_str->len);
  94         if ( gstr->len >= (maxlen - (strlen(gstr_tmp->str) + ext_str->len)) )
  95             gstr = g_string_truncate(gstr, maxlen - (strlen(gstr_tmp->str) + ext_str->len));
  96         gstr = g_string_append(gstr, gstr_tmp->str);
  97         gstr = g_string_append(gstr, ext_str->str);
  98     }
  99     else {
 100         if ( gstr->len >= (maxlen - strlen(gstr_tmp->str)) )
 101             gstr = g_string_truncate(gstr, maxlen - strlen(gstr_tmp->str));
 102         gstr = g_string_append(gstr, gstr_tmp->str);
 103     }
 104
 105     if (ext_str) {
 106         g_string_free(ext_str, TRUE);
 107     }
 108
 109     g_string_free(gstr_tmp, TRUE);
 110     return gstr;
 111 }
 112
 113 GString *
 114 eo_massage_str(const char *in_str, size_t maxlen, int dupn)
 115 {
 116     char *tmp_ptr;
 117     /* The characters in "reject" come from:
 118      * https://docs.microsoft.com/en-us/windows/win32/fileio/naming-a-file#naming-conventions.
 119      * Add to the list as necessary for other OS's.
 120      */
 121     const char *reject = "<>:\"/\\|?*"
 122         "\x01\x02\x03\x04\x05\x06\x07\x08\x09\x0a"
 123     "\x0b\x0c\x0d\x0e\x0f\x10\x11\x12\x13\x14"
 124     "\x15\x16\x17\x18\x19\x1a\x1b\x1c\x1d\x1e\x1f";
 125     GString *out_str;
 126
 127     out_str = g_string_new("");
 128
 129     /* Find all disallowed characters/bytes and replace them with %xx */
 130     while ( (tmp_ptr = strpbrk(in_str, reject)) != NULL ) {
 131         out_str = g_string_append_len(out_str, in_str, tmp_ptr - in_str);
 132         g_string_append_printf(out_str, "%%%02x", *tmp_ptr);
 133         in_str = tmp_ptr + 1;
 134     }
 135     out_str = g_string_append(out_str, in_str);
 136     if ( dupn != 0 || out_str->len > maxlen )
 137         out_str = eo_rename(out_str, maxlen, dupn);
 138     return out_str;
 139 }
 140
 141 const char *
 142 eo_ct2ext(const char *content_type)
 143 {
 144     /* TODO: Map the content type string to an extension string.  If no match,
 145      * return NULL. */
 146     return content_type;
 147 }
 148
 149 void eo_free_entry(export_object_entry_t *entry)
 150 {
 151     g_free(entry->hostname);
 152     g_free(entry->content_type);
 153     g_free(entry->filename);
 154     g_free(entry->payload_data);
 155
 156     g_free(entry);
 157 }
 158
 159 /*
 160  * Editor modelines
 161  *
 162  * Local Variables:
 163  * c-basic-offset: 4
 164  * tab-width: 8
 165  * indent-tabs-mode: nil
 166  * End:
 167  *
 168  * ex: set shiftwidth=4 tabstop=8 expandtab:
 169  * :indentSize=4:tabSize=8:noTabs=true:
 170  */