common/networking/packets.h

   1 /***********************************************************************
   2  Freeciv - Copyright (C) 1996 - A Kjeldberg, L Gregersen, P Unold
   3    This program is free software; you can redistribute it and/or modify
   4    it under the terms of the GNU General Public License as published by
   5    the Free Software Foundation; either version 2, or (at your option)
   6    any later version.
   7
   8    This program is distributed in the hope that it will be useful,
   9    but WITHOUT ANY WARRANTY; without even the implied warranty of
  10    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11    GNU General Public License for more details.
  12 ***********************************************************************/
  13 #ifndef FC__PACKETS_H
  14 #define FC__PACKETS_H
  15
  16 #ifdef __cplusplus
  17 extern "C" {
  18 #endif /* __cplusplus */
  19
  20 struct connection;
  21 struct data_in;
  22
  23 /* utility */
  24 #include "shared.h"             /* MAX_LEN_ADDR */
  25
  26 /* common */
  27 #include "connection.h"         /* struct connection, MAX_LEN_* */
  28 #include "diptreaty.h"
  29 #include "effects.h"
  30 #include "events.h"
  31 #include "improvement.h"        /* bv_imprs */
  32 #include "player.h"
  33 #include "requirements.h"
  34 #include "spaceship.h"
  35 #include "team.h"
  36 #include "tile.h"
  37 #include "traderoutes.h"
  38 #include "unittype.h"
  39 #include "worklist.h"
  40
  41
  42 /* Used in network protocol. */
  43 #define MAX_LEN_MSG             1536
  44 #define MAX_LEN_ROUTE           2000      /* MAX_LEN_PACKET / 2 - header */
  45
  46 #ifdef FREECIV_WEB
  47 #define web_send_packet(packetname, ...) \
  48   send_packet_web_ ##packetname( __VA_ARGS__ )
  49 #define web_lsend_packet(packetname, ...) \
  50   lsend_packet_web_ ##packetname( __VA_ARGS__ )
  51 #else  /* FREECIV_WEB */
  52 #define web_send_packet(packetname, ...)
  53 #define web_lsend_packet(packetname, ...)
  54 #endif /* FREECIV_WEB */
  55
  56 /* The size of opaque (void *) data sent in the network packet.  To avoid
  57  * fragmentation issues, this SHOULD NOT be larger than the standard
  58  * ethernet or PPP 1500 byte frame size (with room for headers).
  59  *
  60  * Do not spend much time optimizing, you have no idea of the actual dynamic
  61  * path characteristics between systems, such as VPNs and tunnels.
  62  *
  63  * Used in network protocol.
  64  */
  65 #define ATTRIBUTE_CHUNK_SIZE    (1400)
  66
  67 /* Used in network protocol. */
  68 enum report_type {
  69   REPORT_WONDERS_OF_THE_WORLD,
  70   REPORT_TOP_5_CITIES,
  71   REPORT_DEMOGRAPHIC,
  72   REPORT_ACHIEVEMENTS
  73 };
  74
  75 /* Used in network protocol. */
  76 enum unit_info_use {
  77   UNIT_INFO_IDENTITY,
  78   UNIT_INFO_CITY_SUPPORTED,
  79   UNIT_INFO_CITY_PRESENT
  80 };
  81
  82 /* Used in network protocol. */
  83 enum authentication_type {
  84   AUTH_LOGIN_FIRST,   /* request a password for a returning user */
  85   AUTH_NEWUSER_FIRST, /* request a password for a new user */
  86   AUTH_LOGIN_RETRY,   /* inform the client to try a different password */
  87   AUTH_NEWUSER_RETRY  /* inform the client to try a different [new] password */
  88 };
  89
  90 #include "packets_gen.h"
  91
  92 struct packet_handlers {
  93   union {
  94     int (*no_packet)(struct connection *pconn);
  95     int (*packet)(struct connection *pconn, const void *packet);
  96     int (*force_to_send)(struct connection *pconn, const void *packet,
  97                          bool force_to_send);
  98   } send[PACKET_LAST];
  99   void *(*receive[PACKET_LAST])(struct connection *pconn);
 100 };
 101
 102 void *get_packet_from_connection_raw(struct connection *pc,
 103                                      enum packet_type *ptype);
 104
 105 #ifdef FREECIV_JSON_CONNECTION
 106 #define get_packet_from_connection(pc, ptype) get_packet_from_connection_json(pc, ptype)
 107 #else
 108 #define get_packet_from_connection(pc, ptype) get_packet_from_connection_raw(pc, ptype)
 109 #endif
 110
 111 void remove_packet_from_buffer(struct socket_packet_buffer *buffer);
 112
 113 void send_attribute_block(const struct player *pplayer,
 114                           struct connection *pconn);
 115 void generic_handle_player_attribute_chunk(struct player *pplayer,
 116                                            const struct
 117                                            packet_player_attribute_chunk
 118                                            *chunk);
 119 void packet_handlers_fill_initial(struct packet_handlers *phandlers);
 120 void packet_handlers_fill_capability(struct packet_handlers *phandlers,
 121                                      const char *capability);
 122 const char *packet_name(enum packet_type type);
 123 bool packet_has_game_info_flag(enum packet_type type);
 124
 125 void packet_header_init(struct packet_header *packet_header);
 126 void post_send_packet_server_join_reply(struct connection *pconn,
 127                                         const struct packet_server_join_reply
 128                                         *packet);
 129 void post_receive_packet_server_join_reply(struct connection *pconn,
 130                                            const struct
 131                                            packet_server_join_reply *packet);
 132
 133 void pre_send_packet_player_attribute_chunk(struct connection *pc,
 134                                             struct packet_player_attribute_chunk
 135                                             *packet);
 136
 137 const struct packet_handlers *packet_handlers_initial(void);
 138 const struct packet_handlers *packet_handlers_get(const char *capability);
 139
 140 void packets_deinit(void);
 141
 142 #ifdef FREECIV_JSON_CONNECTION
 143 #include "packets_json.h"
 144 #else
 145
 146 #define SEND_PACKET_START(packet_type) \
 147   unsigned char buffer[MAX_LEN_PACKET]; \
 148   struct raw_data_out dout; \
 149   \
 150   dio_output_init(&dout, buffer, sizeof(buffer)); \
 151   dio_put_type_raw(&dout, pc->packet_header.length, 0); \
 152   dio_put_type_raw(&dout, pc->packet_header.type, packet_type);
 153
 154 #define SEND_PACKET_END(packet_type) \
 155   { \
 156     size_t size = dio_output_used(&dout); \
 157     \
 158     dio_output_rewind(&dout); \
 159     dio_put_type_raw(&dout, pc->packet_header.length, size); \
 160     fc_assert(!dout.too_short); \
 161     return send_packet_data(pc, buffer, size, packet_type); \
 162   }
 163
 164 #define RECEIVE_PACKET_START(packet_type, result) \
 165   struct data_in din; \
 166   struct packet_type packet_buf, *result = &packet_buf; \
 167   \
 168   dio_input_init(&din, pc->buffer->data, \
 169                  data_type_size(pc->packet_header.length)); \
 170   { \
 171     int size; \
 172   \
 173     dio_get_type_raw(&din, pc->packet_header.length, &size); \
 174     dio_input_init(&din, pc->buffer->data, MIN(size, pc->buffer->ndata)); \
 175   } \
 176   dio_input_skip(&din, (data_type_size(pc->packet_header.length) \
 177                         + data_type_size(pc->packet_header.type)));
 178
 179 #define RECEIVE_PACKET_END(result) \
 180   if (!packet_check(&din, pc)) { \
 181     return NULL; \
 182   } \
 183   remove_packet_from_buffer(pc->buffer); \
 184   result = fc_malloc(sizeof(*result)); \
 185   *result = packet_buf; \
 186   return result;
 187
 188 #define RECEIVE_PACKET_FIELD_ERROR(field, ...) \
 189   log_packet("Error on field '" #field "'" __VA_ARGS__); \
 190   return NULL
 191
 192 #endif /* FREECIV_JSON_PROTOCOL */
 193
 194 int send_packet_data(struct connection *pc, unsigned char *data, int len,
 195                      enum packet_type packet_type);
 196 bool packet_check(struct data_in *din, struct connection *pc);
 197
 198 /* Utilities to exchange strings and string vectors. */
 199 #define PACKET_STRVEC_SEPARATOR '\3'
 200 #define PACKET_STRVEC_COMPUTE(str, strvec)                                  \
 201   if (NULL != strvec) {                                                     \
 202     strvec_to_str(strvec, PACKET_STRVEC_SEPARATOR, str, sizeof(str));       \
 203   } else {                                                                  \
 204     str[0] = '\0';                                                          \
 205   }
 206 #define PACKET_STRVEC_EXTRACT(strvec, str)                                  \
 207   if ('\0' != str[0]) {                                                     \
 208     strvec = strvec_new();                                                  \
 209     strvec_from_str(strvec, PACKET_STRVEC_SEPARATOR, str);                  \
 210   } else {                                                                  \
 211     strvec = NULL;                                                          \
 212   }
 213
 214 #ifdef __cplusplus
 215 }
 216 #endif /* __cplusplus */
 217
 218 #endif  /* FC__PACKETS_H */