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/* |
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* ircd-hybrid: an advanced Internet Relay Chat Daemon(ircd). |
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* |
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* Copyright (C) 2004 Kevin L. Mitchell <klmitch@mit.edu> |
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* Copyright (C) 2006 Hybrid Development Team |
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* |
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* This program is free software; you can redistribute it and/or modify |
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* it under the terms of the GNU General Public License as published by |
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* the Free Software Foundation; either version 2 of the License, or |
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* (at your option) any later version. |
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* |
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* This program is distributed in the hope that it will be useful, |
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* but WITHOUT ANY WARRANTY; without even the implied warranty of |
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
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* GNU General Public License for more details. |
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* |
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* You should have received a copy of the GNU General Public License |
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* along with this program; if not, write to the Free Software |
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* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 |
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* USA |
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* |
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* $Id$ |
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*/ |
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|
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/** @file |
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* @brief Capability negotiation commands |
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* @version $Id$ |
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*/ |
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|
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#include "stdinc.h" |
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#include "handlers.h" |
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#include "client.h" |
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#include "hash.h" |
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#include "ircd.h" |
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#include "numeric.h" |
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#include "s_conf.h" |
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#include "s_user.h" |
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#include "s_serv.h" |
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#include "send.h" |
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#include "msg.h" |
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#include "parse.h" |
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#include "modules.h" |
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#include "common.h" |
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#include "packet.h" |
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#include "irc_string.h" |
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|
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|
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#define CAPFL_HIDDEN 0x0001 /**< Do not advertize this capability */ |
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#define CAPFL_PROHIBIT 0x0002 /**< Client may not set this capability */ |
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#define CAPFL_PROTO 0x0004 /**< Cap must be acknowledged by client */ |
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#define CAPFL_STICKY 0x0008 /**< Cap may not be cleared once set */ |
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|
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typedef int (*bqcmp)(const void *, const void *); |
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|
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static struct capabilities |
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{ |
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unsigned int cap; |
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unsigned int flags; |
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const char *name; |
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size_t namelen; |
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} capab_list[] = { |
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#define _CAP(cap, flags, name) \ |
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{ (cap), (flags), (name), sizeof(name) - 1 } |
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_CAP(CAP_MULTI_PREFIX, 0, "multi-prefix") |
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#undef _CAP |
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}; |
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|
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#define CAPAB_LIST_LEN (sizeof(capab_list) / sizeof(struct capabilities)) |
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|
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static int |
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capab_sort(const struct capabilities *cap1, const struct capabilities *cap2) |
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{ |
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return strcasecmp(cap1->name, cap2->name); |
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} |
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|
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static int |
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capab_search(const char *key, const struct capabilities *cap) |
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{ |
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const char *rb = cap->name; |
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|
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while (ToLower(*key) == ToLower(*rb)) /* walk equivalent part of strings */ |
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if (*key++ == '\0') /* hit the end, all right... */ |
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return 0; |
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else /* OK, let's move on... */ |
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rb++; |
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|
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/* |
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* If the character they differ on happens to be a space, and it happens |
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* to be the same length as the capability name, then we've found a |
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* match; otherwise, return the difference of the two. |
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*/ |
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return (IsSpace(*key) && *rb == '\0') ? 0 : (ToLower(*key) - ToLower(*rb)); |
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} |
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|
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static struct capabilities * |
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find_cap(const char **caplist_p, int *neg_p) |
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{ |
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static int inited = 0; |
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const char *caplist = *caplist_p; |
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struct capabilities *cap = NULL; |
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|
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*neg_p = 0; /* clear negative flag... */ |
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|
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if (!inited) |
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{ |
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/* First, let's sort the array... */ |
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qsort(capab_list, CAPAB_LIST_LEN, sizeof(struct capabilities), (bqcmp)capab_sort); |
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++inited; |
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} |
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|
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/* Next, find first non-whitespace character... */ |
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while (*caplist && IsSpace(*caplist)) |
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++caplist; |
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|
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/* We are now at the beginning of an element of the list; is it negative? */ |
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if (*caplist == '-') |
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{ |
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++caplist; /* yes; step past the flag... */ |
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*neg_p = 1; /* remember that it is negative... */ |
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} |
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|
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/* OK, now see if we can look up the capability... */ |
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if (*caplist) |
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{ |
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if (!(cap = bsearch(caplist, capab_list, CAPAB_LIST_LEN, |
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sizeof(struct capabilities), |
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(bqcmp)capab_search))) |
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{ |
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/* Couldn't find the capability; advance to first whitespace character */ |
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while (*caplist && !IsSpace(*caplist)) |
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++caplist; |
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} |
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else |
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caplist += cap->namelen; /* advance to end of capability name */ |
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} |
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|
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assert(caplist != *caplist_p || !*caplist); /* we *must* advance */ |
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|
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/* move ahead in capability list string--or zero pointer if we hit end */ |
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*caplist_p = *caplist ? caplist : 0; |
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|
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return cap; /* and return the capability (if any) */ |
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} |
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|
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/** Send a CAP \a subcmd list of capability changes to \a source_p. |
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* If more than one line is necessary, each line before the last has |
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* an added "*" parameter before that line's capability list. |
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* @param[in] source_p Client receiving capability list. |
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* @param[in] set Capabilities to show as set (with ack and sticky modifiers). |
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* @param[in] rem Capabalities to show as removed (with no other modifier). |
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* @param[in] subcmd Name of capability subcommand. |
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*/ |
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static int |
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send_caplist(struct Client *source_p, unsigned int set, |
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unsigned int rem, const char *subcmd) |
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{ |
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char capbuf[IRCD_BUFSIZE] = "", pfx[16]; |
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char cmdbuf[IRCD_BUFSIZE] = ""; |
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unsigned int i, loc, len, flags, pfx_len, clen; |
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|
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/* set up the buffer for the final LS message... */ |
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clen = snprintf(cmdbuf, sizeof(capbuf), ":%s CAP %s %s ", me.name, |
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source_p->name[0] ? source_p->name : "*", subcmd); |
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|
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for (i = 0, loc = 0; i < CAPAB_LIST_LEN; ++i) |
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{ |
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flags = capab_list[i].flags; |
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|
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/* |
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* This is a little bit subtle, but just involves applying de |
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* Morgan's laws to the obvious check: We must display the |
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* capability if (and only if) it is set in \a rem or \a set, or |
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* if both are null and the capability is hidden. |
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*/ |
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if (!(rem && (rem & capab_list[i].cap)) && |
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!(set && (set & capab_list[i].cap)) && |
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(rem || set || (flags & CAPFL_HIDDEN))) |
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continue; |
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|
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/* Build the prefix (space separator and any modifiers needed). */ |
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pfx_len = 0; |
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|
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if (loc) |
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pfx[pfx_len++] = ' '; |
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if (rem && (rem & capab_list[i].cap)) |
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pfx[pfx_len++] = '-'; |
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else |
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{ |
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if (flags & CAPFL_PROTO) |
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pfx[pfx_len++] = '~'; |
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if (flags & CAPFL_STICKY) |
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pfx[pfx_len++] = '='; |
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} |
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|
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pfx[pfx_len] = '\0'; |
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|
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len = capab_list[i].namelen + pfx_len; /* how much we'd add... */ |
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|
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if (sizeof(capbuf) < (clen + loc + len + 15)) |
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{ |
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/* would add too much; must flush */ |
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sendto_one(source_p, "%s* :%s", cmdbuf, capbuf); |
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capbuf[(loc = 0)] = '\0'; /* re-terminate the buffer... */ |
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} |
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|
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loc += snprintf(capbuf + loc, sizeof(capbuf) - loc, |
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"%s%s", pfx, capab_list[i].name); |
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} |
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|
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sendto_one(source_p, "%s:%s", cmdbuf, capbuf); |
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|
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return 0; /* convenience return */ |
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} |
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|
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static int |
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cap_ls(struct Client *source_p, const char *caplist) |
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{ |
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if (IsUnknown(source_p)) /* registration hasn't completed; suspend it... */ |
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source_p->localClient->registration |= REG_NEED_CAP; |
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|
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return send_caplist(source_p, 0, 0, "LS"); /* send list of capabilities */ |
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} |
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|
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static int |
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cap_req(struct Client *source_p, const char *caplist) |
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{ |
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const char *cl = caplist; |
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struct capabilities *cap = NULL; |
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unsigned int set = 0, rem = 0; |
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unsigned int cs = source_p->localClient->cap_client; /* capability set */ |
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unsigned int as = source_p->localClient->cap_active; /* active set */ |
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int neg = 0; |
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|
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if (IsUnknown(source_p)) /* registration hasn't completed; suspend it... */ |
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source_p->localClient->registration |= REG_NEED_CAP; |
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|
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while (cl) { /* walk through the capabilities list... */ |
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if (!(cap = find_cap(&cl, &neg)) /* look up capability... */ |
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|| (!neg && (cap->flags & CAPFL_PROHIBIT)) /* is it prohibited? */ |
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|| (neg && (cap->flags & CAPFL_STICKY))) { /* is it sticky? */ |
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sendto_one(source_p, ":%s CAP %s NAK :%s", me.name, |
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source_p->name[0] ? source_p->name : "*", caplist); |
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return 0; /* can't complete requested op... */ |
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} |
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|
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if (neg) |
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{ |
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/* set or clear the capability... */ |
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rem |= cap->cap; |
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set &= ~cap->cap; |
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cs &= ~cap->cap; |
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|
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if (!(cap->flags & CAPFL_PROTO)) |
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as &= ~cap->cap; |
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} |
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else |
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{ |
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rem &= ~cap->cap; |
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set |= cap->cap; |
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cs |= cap->cap; |
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|
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if (!(cap->flags & CAPFL_PROTO)) |
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as |= cap->cap; |
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} |
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} |
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|
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/* Notify client of accepted changes and copy over results. */ |
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send_caplist(source_p, set, rem, "ACK"); |
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|
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source_p->localClient->cap_client = cs; |
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source_p->localClient->cap_active = as; |
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|
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return 0; |
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} |
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|
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static int |
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cap_ack(struct Client *source_p, const char *caplist) |
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{ |
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const char *cl = caplist; |
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struct capabilities *cap = NULL; |
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int neg = 0; |
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|
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/* |
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* Coming from the client, this generally indicates that the client |
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* is using a new backwards-incompatible protocol feature. As such, |
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* it does not require further response from the server. |
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*/ |
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while (cl) |
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{ |
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/* walk through the capabilities list... */ |
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if (!(cap = find_cap(&cl, &neg)) || /* look up capability... */ |
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(neg ? (source_p->localClient->cap_active & cap->cap) : |
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!(source_p->localClient->cap_active & cap->cap))) /* uh... */ |
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continue; |
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|
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if (neg) /* set or clear the active capability... */ |
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source_p->localClient->cap_active &= ~cap->cap; |
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else |
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source_p->localClient->cap_active |= cap->cap; |
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} |
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|
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return 0; |
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} |
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|
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static int |
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cap_clear(struct Client *source_p, const char *caplist) |
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{ |
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struct capabilities *cap = NULL; |
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unsigned int ii; |
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unsigned int cleared = 0; |
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|
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for (ii = 0; ii < CAPAB_LIST_LEN; ++ii) |
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{ |
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cap = &capab_list[ii]; |
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|
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/* Only clear active non-sticky capabilities. */ |
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if (!(source_p->localClient->cap_active & cap->cap) || (cap->flags & CAPFL_STICKY)) |
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continue; |
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|
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cleared |= cap->cap; |
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source_p->localClient->cap_client &= ~cap->cap; |
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|
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if (!(cap->flags & CAPFL_PROTO)) |
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source_p->localClient->cap_active &= ~cap->cap; |
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} |
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|
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return send_caplist(source_p, 0, cleared, "ACK"); |
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} |
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|
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static int |
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cap_end(struct Client *source_p, const char *caplist) |
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{ |
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if (!IsUnknown(source_p)) /* registration has completed... */ |
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return 0; /* so just ignore the message... */ |
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|
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/* capability negotiation is now done... */ |
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source_p->localClient->registration &= ~REG_NEED_CAP; |
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|
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/* if client is now done... */ |
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if (!source_p->localClient->registration) |
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{ |
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register_local_user(source_p); |
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return 0; |
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} |
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|
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return 0; /* Can't do registration yet... */ |
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} |
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|
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static int |
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cap_list(struct Client *source_p, const char *caplist) |
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{ |
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/* Send the list of the client's capabilities */ |
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return send_caplist(source_p, source_p->localClient->cap_client, 0, "LIST"); |
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} |
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|
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static struct subcmd |
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{ |
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const char *cmd; |
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int (*proc)(struct Client *, const char *); |
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} cmdlist[] = { |
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{ "ACK", cap_ack }, |
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{ "CLEAR", cap_clear }, |
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{ "END", cap_end }, |
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{ "LIST", cap_list }, |
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{ "LS", cap_ls }, |
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{ "NAK", NULL }, |
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{ "REQ", cap_req } |
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}; |
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|
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static int |
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subcmd_search(const char *cmd, const struct subcmd *elem) |
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{ |
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return strcasecmp(cmd, elem->cmd); |
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} |
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|
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/** Handle a capability request or response from a client. |
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* \param client_p Client that sent us the message. |
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* \param source_p Original source of message. |
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* \param parc Number of arguments. |
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* \param parv Argument vector. |
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*/ |
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static void |
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m_cap(struct Client *client_p, struct Client *source_p, int parc, char *parv[]) |
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{ |
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const char *subcmd = NULL, *caplist = NULL; |
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struct subcmd *cmd = NULL; |
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|
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if (EmptyString(parv[1])) /* a subcommand is required */ |
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return; |
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|
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subcmd = parv[1]; |
| 392 |
|
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if (parc > 2) /* a capability list was provided */ |
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caplist = parv[2]; |
| 395 |
|
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/* find the subcommand handler */ |
| 397 |
if (!(cmd = bsearch(subcmd, cmdlist, |
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sizeof(cmdlist) / sizeof(struct subcmd), |
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sizeof(struct subcmd), (bqcmp)subcmd_search))) |
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{ |
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sendto_one(source_p, form_str(ERR_INVALIDCAPCMD), me.name, |
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source_p->name[0] ? source_p->name : "*", subcmd); |
| 403 |
return; |
| 404 |
} |
| 405 |
|
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/* then execute it... */ |
| 407 |
if (cmd->proc) |
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(cmd->proc)(source_p, caplist); |
| 409 |
} |
| 410 |
|
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static struct Message cap_msgtab = { |
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"CAP", 0, 0, 2, MAXPARA, MFLG_SLOW, 0, |
| 413 |
{ m_cap, m_cap, m_ignore, m_ignore, m_cap, m_ignore } |
| 414 |
}; |
| 415 |
|
| 416 |
static void |
| 417 |
module_init(void) |
| 418 |
{ |
| 419 |
mod_add_cmd(&cap_msgtab); |
| 420 |
} |
| 421 |
|
| 422 |
static void |
| 423 |
module_exit(void) |
| 424 |
{ |
| 425 |
mod_del_cmd(&cap_msgtab); |
| 426 |
} |
| 427 |
|
| 428 |
struct module module_entry = { |
| 429 |
.node = { NULL, NULL, NULL }, |
| 430 |
.name = NULL, |
| 431 |
.version = "$Revision$", |
| 432 |
.handle = NULL, |
| 433 |
.modinit = module_init, |
| 434 |
.modexit = module_exit, |
| 435 |
.flags = 0 |
| 436 |
}; |
