capture/capture_session.h

   1 /** @file
   2  *
   3  * State of a capture session
   4  *
   5  * Wireshark - Network traffic analyzer
   6  * By Gerald Combs <gerald@wireshark.org>
   7  * Copyright 1998 Gerald Combs
   8  *
   9  * SPDX-License-Identifier: GPL-2.0-or-later
  10  */
  11
  12 #ifndef __CAPCHILD_CAPTURE_SESSION_H__
  13 #define __CAPCHILD_CAPTURE_SESSION_H__
  14
  15 #ifndef _WIN32
  16 #include <sys/types.h>
  17 #include <stdint.h>
  18 #endif
  19
  20 #include "capture_opts.h"
  21
  22 #include <epan/fifo_string_cache.h>
  23 #include <wsutil/processes.h>
  24
  25 #include "cfile.h"
  26
  27 #ifdef __cplusplus
  28 extern "C" {
  29 #endif /* __cplusplus */
  30
  31 #ifdef HAVE_LIBPCAP
  32 /* Current state of capture engine. XXX - differentiate states */
  33 typedef enum {
  34     CAPTURE_STOPPED,        /**< stopped */
  35     CAPTURE_PREPARING,      /**< preparing, but still no response from capture child */
  36     CAPTURE_RUNNING         /**< capture child signalled ok, capture is running now */
  37 } capture_state;
  38
  39 struct _info_data;
  40
  41 /*
  42  * State of a capture session.
  43  */
  44 typedef struct _capture_session capture_session;
  45
  46 /*
  47  * Types of callbacks.
  48  */
  49
  50 /**
  51  * Capture child told us we have a new (or the first) capture file.
  52  */
  53 typedef bool (*new_file_fn)(capture_session *cap_session, char *new_file);
  54
  55 /**
  56  * Capture child told us we have new packets to read.
  57  */
  58 typedef void (*new_packets_fn)(capture_session *cap_session, int to_read);
  59
  60 /**
  61  * Capture child told us how many dropped packets it counted.
  62  */
  63 typedef void (*drops_fn)(capture_session *cap_session, uint32_t dropped,
  64                          const char *interface_name);
  65
  66 /**
  67  * Capture child told us that an error has occurred while starting
  68  * the capture.
  69  */
  70 typedef void (*error_fn)(capture_session *cap_session, char *error_msg,
  71                          char *secondary_error_msg);
  72
  73 /**
  74  * Capture child told us that an error has occurred while parsing a
  75  * capture filter when starting/running the capture.
  76  */
  77 typedef void (*cfilter_error_fn)(capture_session *cap_session, unsigned i,
  78                                  const char *error_message);
  79
  80 /**
  81  * Capture child closed its side of the pipe, report any error and
  82  * do the required cleanup.
  83  */
  84 typedef void (*closed_fn)(capture_session *cap_session, char *msg);
  85
  86 /*
  87  * The structure for the session.
  88  */
  89 struct _capture_session {
  90     ws_process_id fork_child;             /**< If not WS_INVALID_PID, in parent, process ID of child */
  91     int       fork_child_status;          /**< Child exit status */
  92     int       pipe_input_id;              /**< GLib input pipe source ID */
  93 #ifdef _WIN32
  94     int       signal_pipe_write_fd;       /**< the pipe to signal the child */
  95 #endif
  96     capture_state state;                  /**< current state of the capture engine */
  97 #ifndef _WIN32
  98     uid_t     owner;                      /**< owner of the cfile */
  99     gid_t     group;                      /**< group of the cfile */
 100 #endif
 101     bool  session_will_restart;       /**< Set when session will restart */
 102     uint32_t   count;                      /**< Total number of frames captured */
 103     uint32_t   count_pending;              /**< Number of frames captured but not yet read */
 104     capture_options *capture_opts;        /**< options for this capture */
 105     capture_file *cf;                     /**< handle to cfile */
 106     wtap_rec rec;                         /**< record we're reading packet metadata into */
 107     Buffer buf;                           /**< Buffer we're reading packet data into */
 108     struct wtap *wtap;                    /**< current wtap file */
 109     struct _info_data *cap_data_info;     /**< stats for this capture */
 110
 111     // If the user wants to ignore duplicate frames, we need these.
 112     fifo_string_cache_t frame_dup_cache;
 113     GChecksum           *frame_cksum;
 114
 115     /*
 116      * Routines supplied by our caller; we call them back to notify them
 117      * of various events.
 118      */
 119     new_file_fn new_file;
 120     new_packets_fn new_packets;
 121     drops_fn drops;
 122     error_fn error;
 123     cfilter_error_fn cfilter_error;
 124     closed_fn closed;
 125 };
 126
 127 extern void
 128 capture_session_init(capture_session *cap_session, capture_file *cf,
 129                      new_file_fn new_file, new_packets_fn new_packets,
 130                      drops_fn drops, error_fn error,
 131                      cfilter_error_fn cfilter_error, closed_fn closed);
 132
 133 void capture_process_finished(capture_session *cap_session);
 134 #else
 135
 136 /* dummy is needed because clang throws the error: empty struct has size 0 in C, size 1 in C++ */
 137 typedef struct _capture_session {int dummy;} capture_session;
 138
 139 #endif /* HAVE_LIBPCAP */
 140
 141 #ifdef __cplusplus
 142 }
 143 #endif /* __cplusplus */
 144
 145 #endif /* __CAPCHILD_CAPTURE_SESSION_H__ */