ircd/ircd_features.c

   1 /*
   2  * IRC - Internet Relay Chat, ircd/features.c
   3  * Copyright (C) 2000 Kevin L. Mitchell <klmitch@mit.edu>
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 1, or (at your option)
   8  * any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program; if not, write to the Free Software
  17  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  18  */
  19 /** @file
  20  * @brief Implementation of configurable feature support.
  21  * @version $Id: ircd_features.c,v 1.50.2.5 2006/02/16 03:49:54 entrope Exp $
  22  */
  23 #include "config.h"
  24
  25 #include "ircd_features.h"
  26 #include "channel.h"    /* list_set_default */
  27 #include "class.h"
  28 #include "client.h"
  29 #include "hash.h"
  30 #include "ircd.h"
  31 #include "ircd_alloc.h"
  32 #include "ircd_log.h"
  33 #include "ircd_reply.h"
  34 #include "ircd_string.h"
  35 #include "match.h"
  36 #include "motd.h"
  37 #include "msg.h"
  38 #include "numeric.h"
  39 #include "numnicks.h"
  40 #include "random.h"     /* random_seed_set */
  41 #include "s_bsd.h"
  42 #include "s_debug.h"
  43 #include "s_misc.h"
  44 #include "send.h"
  45 #include "struct.h"
  46 #include "sys.h"    /* FALSE bleah */
  47 #include "whowas.h"     /* whowas_realloc */
  48
  49 /* #include <assert.h> -- Now using assert in ircd_log.h */
  50 #include <stdlib.h>
  51 #include <string.h>
  52
  53 struct Client his;
  54
  55 /** List of log output types that can be set */
  56 static struct LogTypes {
  57   char *type; /**< Settable name. */
  58   int (*set)(const char *, const char *); /**< Function to set the value. */
  59   char *(*get)(const char *); /**< Function to get the value. */
  60 } logTypes[] = {
  61   { "FILE", log_set_file, log_get_file },
  62   { "FACILITY", log_set_facility, log_get_facility },
  63   { "SNOMASK", log_set_snomask, log_get_snomask },
  64   { "LEVEL", log_set_level, log_get_level },
  65   { 0, 0, 0 }
  66 };
  67
  68 /** Look up a struct LogType given the type string.
  69  * @param[in] from &Client requesting type, or NULL.
  70  * @param[in] type Name of log type to find.
  71  * @return Pointer to the found LogType, or NULL if none was found.
  72  */
  73 static struct LogTypes *
  74 feature_log_desc(struct Client* from, const char *type)
  75 {
  76   int i;
  77
  78   assert(0 != type);
  79
  80   for (i = 0; logTypes[i].type; i++) /* find appropriate descriptor */
  81     if (!ircd_strcmp(type, logTypes[i].type))
  82       return &logTypes[i];
  83
  84   Debug((DEBUG_ERROR, "Unknown log feature type \"%s\"", type));
  85   if (from) /* send an error; if from is NULL, called from conf parser */
  86     send_reply(from, ERR_BADLOGTYPE, type);
  87   else
  88     log_write(LS_CONFIG, L_ERROR, 0, "Unknown log feature type \"%s\"", type);
  89
  90   return 0; /* not found */
  91 }
  92
  93 /** Set the value of a log output type for a log subsystem.
  94  * @param[in] from &Client trying to set the log type, or NULL.
  95  * @param[in] fields Array of parameters to set.
  96  * @param[in] count Number of parameters in \a fields.
  97  * @return -1 to clear the mark, 0 to leave the mask alone, 1 to set the mask.
  98  */
  99 static int
 100 feature_log_set(struct Client* from, const char* const* fields, int count)
 101 {
 102   struct LogTypes *desc;
 103   char *subsys;
 104
 105   if (count < 2) { /* set default facility */
 106     if (log_set_default(count < 1 ? 0 : fields[0])) {
 107       assert(count >= 1); /* should always accept default */
 108
 109       if (from) /* send an error */
 110         send_reply(from, ERR_BADLOGVALUE, fields[0]);
 111       else
 112         log_write(LS_CONFIG, L_ERROR, 0,
 113                   "Bad value \"%s\" for default facility", fields[0]);
 114     } else
 115       return count < 1 ? -1 : 1; /* tell feature to set or clear mark */
 116   } else if (!(subsys = log_canon(fields[0]))) { /* no such subsystem */
 117     if (from) /* send an error */
 118       send_reply(from, ERR_BADLOGSYS, fields[0]);
 119     else
 120       log_write(LS_CONFIG, L_ERROR, 0,
 121                 "No such logging subsystem \"%s\"", fields[0]);
 122   } else if ((desc = feature_log_desc(from, fields[1]))) { /* set value */
 123     if ((*desc->set)(fields[0], count < 3 ? 0 : fields[2])) {
 124       assert(count >= 3); /* should always accept default */
 125
 126       if (from) /* send an error */
 127         send_reply(from, ERR_BADLOGVALUE, fields[2]);
 128       else
 129         log_write(LS_CONFIG, L_ERROR, 0,
 130                   "Bad value \"%s\" for log type %s (subsystem %s)",
 131                   fields[2], desc->type, subsys);
 132     }
 133   }
 134
 135   return 0;
 136 }
 137
 138 /** Reset a log type for a subsystem to its default value.
 139  * @param[in] from &Client trying to reset the subsystem.
 140  * @param[in] fields Array of parameters to reset.
 141  * @param[in] count Number of fields in \a fields.
 142  * @return -1 to unmark the entry, or zero to leave it alone.
 143  */
 144 static int
 145 feature_log_reset(struct Client* from, const char* const* fields, int count)
 146 {
 147   struct LogTypes *desc;
 148   char *subsys;
 149
 150   assert(0 != from); /* Never called by the .conf parser */
 151
 152   if (count < 1) { /* reset default facility */
 153     log_set_default(0);
 154     return -1; /* unmark this entry */
 155   } else if (count < 2)
 156     need_more_params(from, "RESET");
 157   else if (!(subsys = log_canon(fields[0]))) /* no such subsystem */
 158     send_reply(from, ERR_BADLOGSYS, fields[0]);
 159   else if ((desc = feature_log_desc(from, fields[1]))) /* reset value */
 160     (*desc->set)(fields[0], 0); /* default should always be accepted */
 161
 162   return 0;
 163 }
 164
 165 /** Handle an update to FEAT_HIS_SERVERNAME. */
 166 static void
 167 feature_notify_servername(void)
 168 {
 169   ircd_strncpy(cli_name(&his), feature_str(FEAT_HIS_SERVERNAME), HOSTLEN);
 170 }
 171
 172 /** Handle an update to FEAT_HIS_SERVERINFO. */
 173 static void
 174 feature_notify_serverinfo(void)
 175 {
 176   ircd_strncpy(cli_info(&his), feature_str(FEAT_HIS_SERVERINFO), REALLEN);
 177 }
 178
 179 /** Report the value of a log setting.
 180  * @param[in] from &Client asking for details.
 181  * @param[in] fields Array of parameters to get.
 182  * @param[in] count Number of fields in \a fields.
 183  */
 184 static void
 185 feature_log_get(struct Client* from, const char* const* fields, int count)
 186 {
 187   struct LogTypes *desc;
 188   char *value, *subsys;
 189
 190   assert(0 != from); /* never called by .conf parser */
 191
 192   if (count < 1) /* return default facility */
 193     send_reply(from, SND_EXPLICIT | RPL_FEATURE, ":Log facility: %s",
 194                log_get_default());
 195   else if (count < 2)
 196     need_more_params(from, "GET");
 197   else if (!(subsys = log_canon(fields[0]))) { /* no such subsystem */
 198     send_reply(from, ERR_BADLOGSYS, fields[0]);
 199   } else if ((desc = feature_log_desc(from, fields[1]))) {
 200     if ((value = (*desc->get)(fields[0]))) /* send along value */
 201       send_reply(from, SND_EXPLICIT | RPL_FEATURE,
 202                  ":Log %s for subsystem %s: %s", desc->type, subsys,
 203                  (*desc->get)(subsys));
 204     else
 205       send_reply(from, SND_EXPLICIT | RPL_FEATURE,
 206                  ":No log %s is set for subsystem %s", desc->type, subsys);
 207   }
 208 }
 209
 210 /** Sets a feature to the given value.
 211  * @param[in] from Client trying to set parameters.
 212  * @param[in] fields Array of parameters to set.
 213  * @param[in] count Number of fields in \a count.
 214  * @return <0 to clear the feature mark, 0 to leave it, >0 to set the feature mark.
 215  */
 216 typedef int  (*feat_set_call)(struct Client* from, const char* const* fields, int count);
 217 /** Gets the value of a feature.
 218  * @param[in] from Client trying to get parameters.
 219  * @param[in] fields Array of parameters to set.
 220  * @param[in] count Number of fields in \a count.
 221  */
 222 typedef void (*feat_get_call)(struct Client* from, const char* const* fields, int count);
 223 /** Callback to notify of a feature's change. */
 224 typedef void (*feat_notify_call)(void);
 225 /** Unmarks all sub-feature values prior to reading .conf. */
 226 typedef void (*feat_unmark_call)(void);
 227 /** Resets to defaults all currently unmarked values.
 228  * @param[in] marked Non-zero if the feature is marked.
 229  */
 230 typedef int  (*feat_mark_call)(int marked);
 231 /* Reports features as a /stats f list.
 232  * @param[in] sptr Client asking for feature list.
 233  * @param[in] marked Non-zero if the feature is marked.
 234  */
 235 typedef void (*feat_report_call)(struct Client* sptr, int marked);
 236
 237 #define FEAT_NONE   0x0000      /**< no value */
 238 #define FEAT_INT    0x0001      /**< set if entry contains an integer value */
 239 #define FEAT_BOOL   0x0002      /**< set if entry contains a boolean value */
 240 #define FEAT_STR    0x0003      /**< set if entry contains a string value */
 241 #define FEAT_MASK   0x000f      /**< possible value types */
 242
 243 #define FEAT_MARK   0x0010      /**< set if entry has been changed */
 244 #define FEAT_NULL   0x0020      /**< NULL string is permitted */
 245 #define FEAT_CASE   0x0040      /**< string is case-sensitive */
 246
 247 #define FEAT_OPER   0x0100      /**< set to display only to opers */
 248 #define FEAT_MYOPER 0x0200      /**< set to display only to local opers */
 249 #define FEAT_NODISP 0x0400      /**< feature must never be displayed */
 250
 251 #define FEAT_READ   0x1000      /**< feature is read-only (for now, perhaps?) */
 252
 253 /** Declare a feature with custom behavior. */
 254 #define F_N(type, flags, set, reset, get, notify, unmark, mark, report)       \
 255   { FEAT_ ## type, #type, FEAT_NONE | (flags), 0, 0, 0, 0,                    \
 256     (set), (reset), (get), (notify), (unmark), (mark), (report) }
 257 /** Declare a feature that takes integer values. */
 258 #define F_I(type, flags, v_int, notify)                                       \
 259   { FEAT_ ## type, #type, FEAT_INT | (flags), 0, (v_int), 0, 0,               \
 260     0, 0, 0, (notify), 0, 0, 0 }
 261 /** Declare a feature that takes boolean values. */
 262 #define F_B(type, flags, v_int, notify)                                       \
 263   { FEAT_ ## type, #type, FEAT_BOOL | (flags), 0, (v_int), 0, 0,              \
 264     0, 0, 0, (notify), 0, 0, 0 }
 265 /** Declare a feature that takes string values. */
 266 #define F_S(type, flags, v_str, notify)                                       \
 267   { FEAT_ ## type, #type, FEAT_STR | (flags), 0, 0, 0, (v_str),               \
 268     0, 0, 0, (notify), 0, 0, 0 }
 269
 270 /** Table of feature descriptions. */
 271 static struct FeatureDesc {
 272   enum Feature     feat;    /**< feature identifier */
 273   char*            type;    /**< string describing type */
 274   unsigned int     flags;   /**< flags for feature */
 275   int              v_int;   /**< integer value */
 276   int              def_int; /**< default value */
 277   char*            v_str;   /**< string value */
 278   char*            def_str; /**< default value */
 279   feat_set_call    set;     /**< set feature values */
 280   feat_set_call    reset;   /**< reset feature values to defaults */
 281   feat_get_call    get;     /**< get feature values */
 282   feat_notify_call notify;  /**< notify of value change */
 283   feat_unmark_call unmark;  /**< unmark all feature change values */
 284   feat_mark_call   mark;    /**< reset to defaults all unchanged features */
 285   feat_report_call report;  /**< report feature values */
 286 } features[] = {
 287   /* Misc. features */
 288   F_N(LOG, FEAT_MYOPER, feature_log_set, feature_log_reset, feature_log_get,
 289       0, log_feature_unmark, log_feature_mark, log_feature_report),
 290   F_S(DOMAINNAME, 0, DOMAINNAME, 0),
 291   F_B(RELIABLE_CLOCK, 0, 0, 0),
 292   F_I(BUFFERPOOL, 0, 27000000, 0),
 293   F_B(HAS_FERGUSON_FLUSHER, 0, 0, 0),
 294   F_I(CLIENT_FLOOD, 0, 1024, 0),
 295   F_I(SERVER_PORT, FEAT_OPER, 4400, 0),
 296   F_B(NODEFAULTMOTD, 0, 1, 0),
 297   F_S(MOTD_BANNER, FEAT_NULL, 0, 0),
 298   F_S(PROVIDER, FEAT_NULL, 0, 0),
 299   F_B(KILL_IPMISMATCH, FEAT_OPER, 0, 0),
 300   F_B(IDLE_FROM_MSG, 0, 1, 0),
 301   F_B(HUB, 0, 0, 0),
 302   F_B(WALLOPS_OPER_ONLY, 0, 0, 0),
 303   F_B(NODNS, 0, 0, 0),
 304   F_N(RANDOM_SEED, FEAT_NODISP, random_seed_set, 0, 0, 0, 0, 0, 0),
 305   F_S(DEFAULT_LIST_PARAM, FEAT_NULL, 0, list_set_default),
 306   F_I(NICKNAMEHISTORYLENGTH, 0, 800, whowas_realloc),
 307   F_B(HOST_HIDING, 0, 1, 0),
 308   F_S(HIDDEN_HOST, FEAT_CASE, "users.undernet.org", 0),
 309   F_S(HIDDEN_IP, 0, "127.0.0.1", 0),
 310   F_B(AUTOINVISIBLE, 0, 1, 0),
 311   F_B(CONNEXIT_NOTICES, 0, 0, 0),
 312   F_B(USER_HIDECHANS, 0, 0, 0),
 313   F_B(USER_HIDEIDLETIME, 0, 0, 0),
 314   F_B(OPLEVELS, 0, 1, 0),
 315   F_B(ZANNELS, 0, 1, 0),
 316   F_B(LOCAL_CHANNELS, 0, 1, 0),
 317   F_B(TOPIC_BURST, 0, 0, 0),
 318   F_B(AUTOCHANMODES, 0, 1, 0),
 319   F_S(AUTOCHANMODES_LIST, FEAT_CASE | FEAT_NULL, "ntCN", 0),
 320
 321   /* features that probably should not be touched */
 322   F_I(KILLCHASETIMELIMIT, 0, 30, 0),
 323   F_I(MAXCHANNELSPERUSER, 0, 10, 0),
 324   F_I(NICKLEN, 0, 15, 0),
 325   F_I(AVBANLEN, 0, 40, 0),
 326   F_I(MAXBANS, 0, 45, 0),
 327   F_I(MAXSILES, 0, 15, 0),
 328   F_I(HANGONGOODLINK, 0, 300, 0),
 329   F_I(HANGONRETRYDELAY, 0, 10, 0),
 330   F_I(CONNECTTIMEOUT, 0, 90, 0),
 331   F_I(MAXIMUM_LINKS, 0, 1, init_class), /* reinit class 0 as needed */
 332   F_I(PINGFREQUENCY, 0, 120, init_class),
 333   F_I(CONNECTFREQUENCY, 0, 600, init_class),
 334   F_I(DEFAULTMAXSENDQLENGTH, 0, 40000, init_class),
 335   F_I(GLINEMAXUSERCOUNT, 0, 20, 0),
 336   F_I(SOCKSENDBUF, 0, SERVER_TCP_WINDOW, 0),
 337   F_I(SOCKRECVBUF, 0, SERVER_TCP_WINDOW, 0),
 338   F_I(IPCHECK_CLONE_LIMIT, 0, 4, 0),
 339   F_I(IPCHECK_CLONE_PERIOD, 0, 40, 0),
 340   F_I(IPCHECK_CLONE_DELAY, 0, 600, 0),
 341   F_I(CHANNELLEN, 0, 200, 0),
 342
 343   /* Some misc. default paths */
 344   F_S(MPATH, FEAT_CASE | FEAT_MYOPER, "ircd.motd", motd_init),
 345   F_S(RPATH, FEAT_CASE | FEAT_MYOPER, "remote.motd", motd_init),
 346   F_S(PPATH, FEAT_CASE | FEAT_MYOPER | FEAT_READ, "ircd.pid", 0),
 347
 348   /* Networking features */
 349   F_I(TOS_SERVER, 0, 0x08, 0),
 350   F_I(TOS_CLIENT, 0, 0x08, 0),
 351   F_I(POLLS_PER_LOOP, 0, 200, 0),
 352   F_I(IRCD_RES_RETRIES, 0, 2, 0),
 353   F_I(IRCD_RES_TIMEOUT, 0, 4, 0),
 354   F_I(AUTH_TIMEOUT, 0, 9, 0),
 355   F_B(ANNOUNCE_INVITES, 0, 0, 0),
 356
 357   /* features that affect all operators */
 358   F_B(EXTENDED_CHECKCMD, 0, 0, 0),
 359   F_B(CONFIG_OPERCMDS, 0, 0, 0),
 360   F_B(SETHOST, 0, 0, 0),
 361   F_B(SETHOST_FREEFORM, 0, 0, 0),
 362   F_B(SETHOST_USER, 0, 0, 0),
 363   F_B(SETHOST_AUTO, 0, 0, 0),
 364
 365   /* HEAD_IN_SAND Features */
 366   F_B(HIS_SNOTICES, 0, 1, 0),
 367   F_B(HIS_SNOTICES_OPER_ONLY, 0, 1, 0),
 368   F_B(HIS_DEBUG_OPER_ONLY, 0, 1, 0),
 369   F_B(HIS_WALLOPS, 0, 1, 0),
 370   F_B(HIS_MAP, 0, 1, 0),
 371   F_B(HIS_LINKS, 0, 1, 0),
 372   F_B(HIS_TRACE, 0, 1, 0),
 373   F_B(HIS_STATS_a, 0, 1, 0),
 374   F_B(HIS_STATS_c, 0, 1, 0),
 375   F_B(HIS_STATS_d, 0, 1, 0),
 376   F_B(HIS_STATS_e, 0, 1, 0),
 377   F_B(HIS_STATS_f, 0, 1, 0),
 378   F_B(HIS_STATS_g, 0, 1, 0),
 379   F_B(HIS_STATS_i, 0, 1, 0),
 380   F_B(HIS_STATS_j, 0, 1, 0),
 381   F_B(HIS_STATS_J, 0, 1, 0),
 382   F_B(HIS_STATS_k, 0, 1, 0),
 383   F_B(HIS_STATS_l, 0, 1, 0),
 384   F_B(HIS_STATS_L, 0, 1, 0),
 385   F_B(HIS_STATS_M, 0, 1, 0),
 386   F_B(HIS_STATS_m, 0, 1, 0),
 387   F_B(HIS_STATS_o, 0, 1, 0),
 388   F_B(HIS_STATS_p, 0, 1, 0),
 389   F_B(HIS_STATS_q, 0, 1, 0),
 390   F_B(HIS_STATS_R, 0, 1, 0),
 391   F_B(HIS_STATS_r, 0, 1, 0),
 392   F_B(HIS_STATS_s, 0, 1, 0),
 393   F_B(HIS_STATS_t, 0, 1, 0),
 394   F_B(HIS_STATS_T, 0, 1, 0),
 395   F_B(HIS_STATS_u, 0, 0, 0),
 396   F_B(HIS_STATS_U, 0, 1, 0),
 397   F_B(HIS_STATS_v, 0, 1, 0),
 398   F_B(HIS_STATS_w, 0, 0, 0),
 399   F_B(HIS_STATS_x, 0, 1, 0),
 400   F_B(HIS_STATS_y, 0, 1, 0),
 401   F_B(HIS_STATS_z, 0, 1, 0),
 402   F_B(HIS_STATS_IAUTH, 0, 1, 0),
 403   F_B(HIS_WHOIS_SERVERNAME, 0, 1, 0),
 404   F_B(HIS_WHOIS_IDLETIME, 0, 1, 0),
 405   F_B(HIS_WHOIS_LOCALCHAN, 0, 1, 0),
 406   F_B(HIS_WHO_SERVERNAME, 0, 1, 0),
 407   F_B(HIS_WHO_HOPCOUNT, 0, 1, 0),
 408   F_B(HIS_WHO_FILTERIP, 0, 1, 0),
 409   F_B(HIS_MODEWHO, 0, 1, 0),
 410   F_B(HIS_BANWHO, 0, 1, 0),
 411   F_B(HIS_KILLWHO, 0, 1, 0),
 412   /* Asuka - Reimplement HEAD_IN_SAND_GLINE from Lain */
 413   F_B(HIS_GLINE, 0, 1, 0),
 414   F_B(HIS_REWRITE, 0, 1, 0),
 415   F_I(HIS_REMOTE, 0, 1, 0),
 416   F_B(HIS_NETSPLIT, 0, 1, 0),
 417   F_S(HIS_SERVERNAME, 0, "*.undernet.org", feature_notify_servername),
 418   F_S(HIS_SERVERINFO, 0, "The Undernet Underworld", feature_notify_serverinfo),
 419   F_S(HIS_URLSERVERS, 0, "http://www.undernet.org/servers.php", 0),
 420   F_B(HIS_USERGLINE, 0, 1, 0),
 421
 422   /* Misc. random stuff */
 423   F_S(NETWORK, 0, "UnderNet", 0),
 424   F_S(URL_CLIENTS, 0, "ftp://ftp.undernet.org/pub/irc/clients", 0),
 425
 426 #undef F_S
 427 #undef F_B
 428 #undef F_I
 429 #undef F_N
 430   { FEAT_LAST_F, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }
 431 };
 432
 433 /** Given a feature's identifier, look up the feature descriptor.
 434  * @param[in] from Client looking up feature, or NULL.
 435  * @param[in] feature Feature name to find.
 436  * @return Pointer to a FeatureDesc, or NULL if none was found.
 437  */
 438 static struct FeatureDesc *
 439 feature_desc(struct Client* from, const char *feature)
 440 {
 441   int i;
 442
 443   assert(0 != feature);
 444
 445   for (i = 0; features[i].type; i++) /* find appropriate descriptor */
 446     if (!strcmp(feature, features[i].type))
 447       return &features[i];
 448
 449   Debug((DEBUG_ERROR, "Unknown feature \"%s\"", feature));
 450   if (from) /* report an error */
 451     send_reply(from, ERR_NOFEATURE, feature);
 452   else
 453     log_write(LS_CONFIG, L_ERROR, 0, "Unknown feature \"%s\"", feature);
 454
 455   return 0; /* not found */
 456 }
 457
 458 /** Given a feature vector string, set the value of a feature.
 459  * @param[in] from Client trying to set the feature, or NULL.
 460  * @param[in] fields Parameters to set, starting with feature name.
 461  * @param[in] count Number of fields in \a fields.
 462  * @return Zero (or, theoretically, CPTR_KILLED).
 463  */
 464 int
 465 feature_set(struct Client* from, const char* const* fields, int count)
 466 {
 467   int i, change = 0, tmp;
 468   const char *t_str;
 469   struct FeatureDesc *feat;
 470
 471   if (from && !HasPriv(from, PRIV_SET))
 472     return send_reply(from, ERR_NOPRIVILEGES);
 473
 474   if (count < 1) {
 475     if (from) /* report an error in the number of arguments */
 476       need_more_params(from, "SET");
 477     else
 478       log_write(LS_CONFIG, L_ERROR, 0, "Not enough fields in F line");
 479   } else if ((feat = feature_desc(from, fields[0]))) { /* find feature */
 480     if (from && feat->flags & FEAT_READ)
 481       return send_reply(from, ERR_NOFEATURE, fields[0]);
 482
 483     switch (feat->flags & FEAT_MASK) {
 484     case FEAT_NONE:
 485       if (feat->set && (i = (*feat->set)(from, fields + 1, count - 1))) {
 486         change++; /* feature handler wants a change recorded */
 487
 488         if (i > 0) /* call the set callback and do marking */
 489           feat->flags |= FEAT_MARK;
 490         else /* i < 0 */
 491           feat->flags &= ~FEAT_MARK;
 492         break;
 493       }
 494
 495     case FEAT_INT: /* an integer value */
 496       tmp = feat->v_int; /* detect changes... */
 497
 498       if (count < 2) { /* reset value */
 499         feat->v_int = feat->def_int;
 500         feat->flags &= ~FEAT_MARK;
 501       } else { /* ok, figure out the value and whether to mark it */
 502         feat->v_int = strtoul(fields[1], 0, 0);
 503         if (feat->v_int == feat->def_int)
 504           feat->flags &= ~FEAT_MARK;
 505         else
 506           feat->flags |= FEAT_MARK;
 507       }
 508
 509       if (feat->v_int != tmp) /* check for change */
 510         change++;
 511       break;
 512
 513     case FEAT_BOOL: /* it's a boolean value--true or false */
 514       tmp = feat->v_int; /* detect changes... */
 515
 516       if (count < 2) { /* reset value */
 517         feat->v_int = feat->def_int;
 518         feat->flags &= ~FEAT_MARK;
 519       } else { /* figure out the value and whether to mark it */
 520         if (!ircd_strncmp(fields[1], "TRUE", strlen(fields[1])) ||
 521             !ircd_strncmp(fields[1], "YES", strlen(fields[1])) ||
 522             (strlen(fields[1]) >= 2 &&
 523              !ircd_strncmp(fields[1], "ON", strlen(fields[1]))))
 524           feat->v_int = 1;
 525         else if (!ircd_strncmp(fields[1], "FALSE", strlen(fields[1])) ||
 526                  !ircd_strncmp(fields[1], "NO", strlen(fields[1])) ||
 527                  (strlen(fields[1]) >= 2 &&
 528                   !ircd_strncmp(fields[1], "OFF", strlen(fields[1]))))
 529           feat->v_int = 0;
 530         else if (from) /* report an error... */
 531           return send_reply(from, ERR_BADFEATVALUE, fields[1], feat->type);
 532         else {
 533           log_write(LS_CONFIG, L_ERROR, 0, "Bad value \"%s\" for feature %s",
 534                     fields[1], feat->type);
 535           return 0;
 536         }
 537
 538         if (feat->v_int == feat->def_int) /* figure out whether to mark it */
 539           feat->flags &= ~FEAT_MARK;
 540         else
 541           feat->flags |= FEAT_MARK;
 542       }
 543
 544       if (feat->v_int != tmp) /* check for change */
 545         change++;
 546       break;
 547
 548     case FEAT_STR: /* it's a string value */
 549       if (count < 2)
 550         t_str = feat->def_str; /* changing to default */
 551       else
 552         t_str = *fields[1] ? fields[1] : 0;
 553
 554       if (!t_str && !(feat->flags & FEAT_NULL)) { /* NULL value permitted? */
 555         if (from)
 556           return send_reply(from, ERR_BADFEATVALUE, "NULL", feat->type);
 557         else {
 558           log_write(LS_CONFIG, L_ERROR, 0, "Bad value \"NULL\" for feature %s",
 559                     feat->type);
 560           return 0;
 561         }
 562       }
 563
 564       if (t_str == feat->def_str ||
 565           (t_str && feat->def_str &&
 566            !(feat->flags & FEAT_CASE ? strcmp(t_str, feat->def_str) :
 567              ircd_strcmp(t_str, feat->def_str)))) { /* resetting to default */
 568         if (feat->v_str != feat->def_str) {
 569           change++; /* change from previous value */
 570
 571           if (feat->v_str)
 572             MyFree(feat->v_str); /* free old value */
 573         }
 574
 575         feat->v_str = feat->def_str; /* very special... */
 576
 577         feat->flags &= ~FEAT_MARK;
 578       } else if (!t_str) {
 579         if (feat->v_str) {
 580           change++; /* change from previous value */
 581
 582           if (feat->v_str != feat->def_str)
 583             MyFree(feat->v_str); /* free old value */
 584         }
 585
 586         feat->v_str = 0; /* set it to NULL */
 587
 588         feat->flags |= FEAT_MARK;
 589       } else if (!feat->v_str ||
 590                  (feat->flags & FEAT_CASE ? strcmp(t_str, feat->v_str) :
 591                   ircd_strcmp(t_str, feat->v_str))) { /* new value */
 592         change++; /* change from previous value */
 593
 594         if (feat->v_str && feat->v_str != feat->def_str)
 595           MyFree(feat->v_str); /* free old value */
 596         DupString(feat->v_str, t_str); /* store new value */
 597
 598         feat->flags |= FEAT_MARK;
 599       } else /* they match, but don't match the default */
 600         feat->flags |= FEAT_MARK;
 601       break;
 602     }
 603
 604     if (change && feat->notify) /* call change notify function */
 605       (*feat->notify)();
 606   }
 607
 608   return 0;
 609 }
 610
 611 /** Reset a feature to its default values.
 612  * @param[in] from Client trying to reset the feature, or NULL.
 613  * @param[in] fields Parameters to set, starting with feature name.
 614  * @param[in] count Number of fields in \a fields.
 615  * @return Zero (or, theoretically, CPTR_KILLED).
 616  */
 617 int
 618 feature_reset(struct Client* from, const char* const* fields, int count)
 619 {
 620   int i, change = 0;
 621   struct FeatureDesc *feat;
 622
 623   assert(0 != from);
 624
 625   if (!HasPriv(from, PRIV_SET))
 626     return send_reply(from, ERR_NOPRIVILEGES);
 627
 628   if (count < 1) /* check arguments */
 629     need_more_params(from, "RESET");
 630   else if ((feat = feature_desc(from, fields[0]))) { /* get descriptor */
 631     if (from && feat->flags & FEAT_READ)
 632       return send_reply(from, ERR_NOFEATURE, fields[0]);
 633
 634     switch (feat->flags & FEAT_MASK) {
 635     case FEAT_NONE: /* None... */
 636       if (feat->reset && (i = (*feat->reset)(from, fields + 1, count - 1))) {
 637         change++; /* feature handler wants a change recorded */
 638
 639         if (i > 0) /* call reset callback and parse mark return */
 640           feat->flags |= FEAT_MARK;
 641         else /* i < 0 */
 642           feat->flags &= ~FEAT_MARK;
 643       }
 644       break;
 645
 646     case FEAT_INT:  /* Integer... */
 647     case FEAT_BOOL: /* Boolean... */
 648       if (feat->v_int != feat->def_int)
 649         change++; /* change will be made */
 650
 651       feat->v_int = feat->def_int; /* set the default */
 652       feat->flags &= ~FEAT_MARK; /* unmark it */
 653       break;
 654
 655     case FEAT_STR: /* string! */
 656       if (feat->v_str != feat->def_str) {
 657         change++; /* change has been made */
 658         if (feat->v_str)
 659           MyFree(feat->v_str); /* free old value */
 660       }
 661
 662       feat->v_str = feat->def_str; /* set it to default */
 663       feat->flags &= ~FEAT_MARK; /* unmark it */
 664       break;
 665     }
 666
 667     if (change && feat->notify) /* call change notify function */
 668       (*feat->notify)();
 669   }
 670
 671   return 0;
 672 }
 673
 674 /** Gets the value of a specific feature and reports it to the user.
 675  * @param[in] from Client trying to get the feature.
 676  * @param[in] fields Parameters to set, starting with feature name.
 677  * @param[in] count Number of fields in \a fields.
 678  * @return Zero (or, theoretically, CPTR_KILLED).
 679  */
 680 int
 681 feature_get(struct Client* from, const char* const* fields, int count)
 682 {
 683   struct FeatureDesc *feat;
 684
 685   assert(0 != from);
 686
 687   if (count < 1) /* check parameters */
 688     need_more_params(from, "GET");
 689   else if ((feat = feature_desc(from, fields[0]))) {
 690     if ((feat->flags & FEAT_NODISP) ||
 691         (feat->flags & FEAT_MYOPER && !MyOper(from)) ||
 692         (feat->flags & FEAT_OPER && !IsAnOper(from))) /* check privs */
 693       return send_reply(from, ERR_NOPRIVILEGES);
 694
 695     switch (feat->flags & FEAT_MASK) {
 696     case FEAT_NONE: /* none, call the callback... */
 697       if (feat->get) /* if there's a callback, use it */
 698         (*feat->get)(from, fields + 1, count - 1);
 699       break;
 700
 701     case FEAT_INT: /* integer, report integer value */
 702       send_reply(from, SND_EXPLICIT | RPL_FEATURE,
 703                  ":Integer value of %s: %d", feat->type, feat->v_int);
 704       break;
 705
 706     case FEAT_BOOL: /* boolean, report boolean value */
 707       send_reply(from, SND_EXPLICIT | RPL_FEATURE,
 708                  ":Boolean value of %s: %s", feat->type,
 709                  feat->v_int ? "TRUE" : "FALSE");
 710       break;
 711
 712     case FEAT_STR: /* string, report string value */
 713       if (feat->v_str) /* deal with null case */
 714         send_reply(from, SND_EXPLICIT | RPL_FEATURE,
 715                    ":String value of %s: %s", feat->type, feat->v_str);
 716       else
 717         send_reply(from, SND_EXPLICIT | RPL_FEATURE,
 718                    ":String value for %s not set", feat->type);
 719       break;
 720     }
 721   }
 722
 723   return 0;
 724 }
 725
 726 /** Called before reading the .conf to clear all dirty marks. */
 727 void
 728 feature_unmark(void)
 729 {
 730   int i;
 731
 732   for (i = 0; features[i].type; i++) {
 733     features[i].flags &= ~FEAT_MARK; /* clear the marks... */
 734     if (features[i].unmark) /* call the unmark callback if necessary */
 735       (*features[i].unmark)();
 736   }
 737 }
 738
 739 /** Called after reading the .conf to reset unmodified values to defaults. */
 740 void
 741 feature_mark(void)
 742 {
 743   int i, change;
 744
 745   for (i = 0; features[i].type; i++) {
 746     change = 0;
 747
 748     switch (features[i].flags & FEAT_MASK) {
 749     case FEAT_NONE:
 750       if (features[i].mark &&
 751           (*features[i].mark)(features[i].flags & FEAT_MARK ? 1 : 0))
 752         change++; /* feature handler wants a change recorded */
 753       break;
 754
 755     case FEAT_INT:  /* Integers or Booleans... */
 756     case FEAT_BOOL:
 757       if (!(features[i].flags & FEAT_MARK)) { /* not changed? */
 758         if (features[i].v_int != features[i].def_int)
 759           change++; /* we're making a change */
 760         features[i].v_int = features[i].def_int;
 761       }
 762       break;
 763
 764     case FEAT_STR: /* strings... */
 765       if (!(features[i].flags & FEAT_MARK)) { /* not changed? */
 766         if (features[i].v_str != features[i].def_str) {
 767           change++; /* we're making a change */
 768           if (features[i].v_str)
 769             MyFree(features[i].v_str); /* free old value */
 770         }
 771         features[i].v_str = features[i].def_str;
 772       }
 773       break;
 774     }
 775
 776     if (change && features[i].notify)
 777       (*features[i].notify)(); /* call change notify function */
 778   }
 779 }
 780
 781 /** Initialize the features subsystem. */
 782 void
 783 feature_init(void)
 784 {
 785   int i;
 786
 787   for (i = 0; features[i].type; i++) {
 788     switch (features[i].flags & FEAT_MASK) {
 789     case FEAT_NONE: /* you're on your own */
 790       break;
 791
 792     case FEAT_INT:  /* Integers or Booleans... */
 793     case FEAT_BOOL:
 794       features[i].v_int = features[i].def_int;
 795       break;
 796
 797     case FEAT_STR:  /* Strings */
 798       features[i].v_str = features[i].def_str;
 799       assert(features[i].def_str || (features[i].flags & FEAT_NULL));
 800       break;
 801     }
 802   }
 803
 804   cli_magic(&his) = CLIENT_MAGIC;
 805   cli_status(&his) = STAT_SERVER;
 806   feature_notify_servername();
 807   feature_notify_serverinfo();
 808 }
 809
 810 /** Report all F-lines to a user.
 811  * @param[in] to Client requesting statistics.
 812  * @param[in] sd Stats descriptor for request (ignored).
 813  * @param[in] param Extra parameter from user (ignored).
 814  */
 815 void
 816 feature_report(struct Client* to, const struct StatDesc* sd, char* param)
 817 {
 818   int i;
 819
 820   for (i = 0; features[i].type; i++) {
 821     if ((features[i].flags & FEAT_NODISP) ||
 822         (features[i].flags & FEAT_MYOPER && !MyOper(to)) ||
 823         (features[i].flags & FEAT_OPER && !IsAnOper(to)))
 824       continue; /* skip this one */
 825
 826     switch (features[i].flags & FEAT_MASK) {
 827     case FEAT_NONE:
 828       if (features[i].report) /* let the callback handle this */
 829         (*features[i].report)(to, features[i].flags & FEAT_MARK ? 1 : 0);
 830       break;
 831
 832
 833     case FEAT_INT: /* Report an F-line with integer values */
 834       if (features[i].flags & FEAT_MARK) /* it's been changed */
 835         send_reply(to, SND_EXPLICIT | RPL_STATSFLINE, "F %s %d",
 836                    features[i].type, features[i].v_int);
 837       break;
 838
 839     case FEAT_BOOL: /* Report an F-line with boolean values */
 840       if (features[i].flags & FEAT_MARK) /* it's been changed */
 841         send_reply(to, SND_EXPLICIT | RPL_STATSFLINE, "F %s %s",
 842                    features[i].type, features[i].v_int ? "TRUE" : "FALSE");
 843       break;
 844
 845     case FEAT_STR: /* Report an F-line with string values */
 846       if (features[i].flags & FEAT_MARK) { /* it's been changed */
 847         if (features[i].v_str)
 848           send_reply(to, SND_EXPLICIT | RPL_STATSFLINE, "F %s %s",
 849                      features[i].type, features[i].v_str);
 850         else /* Actually, F:<type> would reset it; you want F:<type>: */
 851           send_reply(to, SND_EXPLICIT | RPL_STATSFLINE, "F %s",
 852                      features[i].type);
 853       }
 854       break;
 855     }
 856   }
 857 }
 858
 859 /** Return a feature's integer value.
 860  * @param[in] feat &Feature identifier.
 861  * @return Integer value of feature.
 862  */
 863 int
 864 feature_int(enum Feature feat)
 865 {
 866   assert(features[feat].feat == feat);
 867   assert((features[feat].flags & FEAT_MASK) == FEAT_INT);
 868
 869   return features[feat].v_int;
 870 }
 871
 872 /** Return a feature's boolean value.
 873  * @param[in] feat &Feature identifier.
 874  * @return Boolean value of feature.
 875  */
 876 int
 877 feature_bool(enum Feature feat)
 878 {
 879   assert(feat <= FEAT_LAST_F);
 880   if (FEAT_LAST_F < feat)
 881     return 0;
 882   assert(features[feat].feat == feat);
 883   assert((features[feat].flags & FEAT_MASK) == FEAT_BOOL);
 884
 885   return features[feat].v_int;
 886 }
 887
 888 /** Return a feature's string value.
 889  * @param[in] feat &Feature identifier.
 890  * @return String value of feature.
 891  */
 892 const char *
 893 feature_str(enum Feature feat)
 894 {
 895   assert(features[feat].feat == feat);
 896   assert((features[feat].flags & FEAT_MASK) == FEAT_STR);
 897
 898   return features[feat].v_str;
 899 }