xK/src/kike.c

2923 lines
80 KiB
C

/*
* kike.c: the experimental IRC daemon
*
* Copyright (c) 2014, Přemysl Janouch <p.janouch@gmail.com>
* All rights reserved.
*
* Permission to use, copy, modify, and/or distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
* SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
* OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
* CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*
*/
#define PROGRAM_NAME "kike"
#define PROGRAM_VERSION "alpha"
#include "common.c"
#include <nl_types.h>
// --- Configuration (application-specific) ------------------------------------
static struct config_item g_config_table[] =
{
{ "server_name", NULL, "Server name" },
{ "server_info", "My server", "Brief server description" },
{ "motd", NULL, "MOTD filename" },
{ "catalog", NULL, "catgets localization catalog" },
{ "bind_host", NULL, "Address of the IRC server" },
{ "bind_port", "6667", "Port of the IRC server" },
{ "ssl_cert", NULL, "Server SSL certificate (PEM)" },
{ "ssl_key", NULL, "Server SSL private key (PEM)" },
{ "max_connections", "0", "Global connection limit" },
{ "ping_interval", "180", "Interval between PING's (sec)" },
{ NULL, NULL, NULL }
};
// --- Signals -----------------------------------------------------------------
static int g_signal_pipe[2]; ///< A pipe used to signal... signals
/// Program termination has been requested by a signal
static volatile sig_atomic_t g_termination_requested;
static void
sigterm_handler (int signum)
{
(void) signum;
g_termination_requested = true;
int original_errno = errno;
if (write (g_signal_pipe[1], "t", 1) == -1)
soft_assert (errno == EAGAIN);
errno = original_errno;
}
static void
setup_signal_handlers (void)
{
if (pipe (g_signal_pipe) == -1)
exit_fatal ("%s: %s", "pipe", strerror (errno));
set_cloexec (g_signal_pipe[0]);
set_cloexec (g_signal_pipe[1]);
// So that the pipe cannot overflow; it would make write() block within
// the signal handler, which is something we really don't want to happen.
// The same holds true for read().
set_blocking (g_signal_pipe[0], false);
set_blocking (g_signal_pipe[1], false);
signal (SIGPIPE, SIG_IGN);
struct sigaction sa;
sa.sa_flags = SA_RESTART;
sigemptyset (&sa.sa_mask);
sa.sa_handler = sigterm_handler;
if (sigaction (SIGINT, &sa, NULL) == -1
|| sigaction (SIGTERM, &sa, NULL) == -1)
exit_fatal ("%s: %s", "sigaction", strerror (errno));
}
// --- IRC token validation ----------------------------------------------------
// Use the enum only if applicable and a simple boolean isn't sufficient.
enum validation_result
{
VALIDATION_OK,
VALIDATION_ERROR_EMPTY,
VALIDATION_ERROR_TOO_LONG,
VALIDATION_ERROR_INVALID
};
// Everything as per RFC 2812
#define IRC_MAX_NICKNAME 9
#define IRC_MAX_HOSTNAME 63
#define IRC_MAX_CHANNEL_NAME 50
#define IRC_MAX_MESSAGE_LENGTH 510
static bool
irc_regex_match (const char *regex, const char *s)
{
static struct str_map cache;
static bool initialized;
if (!initialized)
{
regex_cache_init (&cache);
initialized = true;
}
struct error *e = NULL;
bool result = regex_cache_match (&cache, regex,
REG_EXTENDED | REG_NOSUB, s, &e);
hard_assert (!e);
return result;
}
static const char *
irc_validate_to_str (enum validation_result result)
{
switch (result)
{
case VALIDATION_OK: return "success";
case VALIDATION_ERROR_EMPTY: return "the value is empty";
case VALIDATION_ERROR_INVALID: return "invalid format";
case VALIDATION_ERROR_TOO_LONG: return "the value is too long";
default: abort ();
}
}
// Anything to keep it as short as possible
#define SN "[0-9A-Za-z][-0-9A-Za-z]*[0-9A-Za-z]*"
#define N4 "[0-9]{1,3}"
#define N6 "[0-9ABCDEFabcdef]{1,}"
#define LE "A-Za-z"
#define SP "][\\\\`_^{|}"
static enum validation_result
irc_validate_hostname (const char *hostname)
{
if (!*hostname)
return VALIDATION_ERROR_EMPTY;
if (!irc_regex_match ("^" SN "(\\." SN ")*$", hostname))
return VALIDATION_ERROR_INVALID;
if (strlen (hostname) > IRC_MAX_HOSTNAME)
return VALIDATION_ERROR_TOO_LONG;
return VALIDATION_OK;
}
static bool
irc_is_valid_hostaddr (const char *hostaddr)
{
if (irc_regex_match ("^" N4 "\\." N4 "\\." N4 "\\." N4 "$", hostaddr)
|| irc_regex_match ("^" N6 ":" N6 ":" N6 ":" N6 ":"
N6 ":" N6 ":" N6 ":" N6 "$", hostaddr)
|| irc_regex_match ("^0:0:0:0:0:(0|[Ff]{4}):"
N4 "\\." N4 "\\." N4 "\\." N4 "$", hostaddr))
return true;
return false;
}
static bool
irc_is_valid_host (const char *host)
{
return irc_validate_hostname (host) == VALIDATION_OK
|| irc_is_valid_hostaddr (host);
}
static bool
irc_is_valid_user (const char *user)
{
return irc_regex_match ("^[^\r\n @]+$", user);
}
static bool
irc_validate_nickname (const char *nickname)
{
if (!*nickname)
return VALIDATION_ERROR_EMPTY;
if (!irc_regex_match ("^[" SP LE "][" SP LE "0-9-]*$", nickname))
return VALIDATION_ERROR_INVALID;
if (strlen (nickname) > IRC_MAX_NICKNAME)
return VALIDATION_ERROR_TOO_LONG;
return VALIDATION_OK;
}
static enum validation_result
irc_validate_channel_name (const char *channel_name)
{
if (!*channel_name)
return VALIDATION_ERROR_EMPTY;
if (*channel_name != '#' || strpbrk (channel_name, "\7\r\n ,:"))
return VALIDATION_ERROR_INVALID;
if (strlen (channel_name) > IRC_MAX_CHANNEL_NAME)
return VALIDATION_ERROR_TOO_LONG;
return VALIDATION_OK;
}
static bool
irc_is_valid_key (const char *key)
{
// XXX: should be 7-bit as well but whatever
return irc_regex_match ("^[^\r\n\f\t\v ]{1,23}$", key);
}
#undef SN
#undef N4
#undef N6
#undef LE
#undef SP
// --- Application data --------------------------------------------------------
#define IRC_SUPPORTED_USER_MODES "aiwros"
enum
{
IRC_USER_MODE_INVISIBLE = (1 << 0),
IRC_USER_MODE_RX_WALLOPS = (1 << 1),
IRC_USER_MODE_RESTRICTED = (1 << 2),
IRC_USER_MODE_OPERATOR = (1 << 3),
IRC_USER_MODE_RX_SERVER_NOTICES = (1 << 4)
};
struct client
{
LIST_HEADER (client)
struct server_context *ctx; ///< Server context
int socket_fd; ///< The TCP socket
struct str read_buffer; ///< Unprocessed input
struct str write_buffer; ///< Output yet to be sent out
bool initialized; ///< Has any data been received yet?
bool registered; ///< The user has registered
bool closing_link; ///< Closing link
bool ssl_rx_want_tx; ///< SSL_read() wants to write
bool ssl_tx_want_rx; ///< SSL_write() wants to read
SSL *ssl; ///< SSL connection
char *nickname; ///< IRC nickname (main identifier)
char *username; ///< IRC username
char *realname; ///< IRC realname (e-mail)
char *hostname; ///< Hostname shown to the network
unsigned mode; ///< User's mode
char *away_message; ///< Away message
time_t last_active; ///< Last PRIVMSG, to get idle time
};
static void
client_init (struct client *self)
{
memset (self, 0, sizeof *self);
self->socket_fd = -1;
str_init (&self->read_buffer);
str_init (&self->write_buffer);
}
static void
client_free (struct client *self)
{
if (!soft_assert (self->socket_fd == -1))
xclose (self->socket_fd);
if (self->ssl)
SSL_free (self->ssl);
str_free (&self->read_buffer);
str_free (&self->write_buffer);
free (self->nickname);
free (self->username);
free (self->realname);
free (self->hostname);
free (self->away_message);
}
static void
client_mode_to_str (unsigned m, struct str *out)
{
if (m & IRC_USER_MODE_INVISIBLE) str_append_c (out, 'i');
if (m & IRC_USER_MODE_RX_WALLOPS) str_append_c (out, 'w');
if (m & IRC_USER_MODE_RESTRICTED) str_append_c (out, 'r');
if (m & IRC_USER_MODE_OPERATOR) str_append_c (out, 'o');
if (m & IRC_USER_MODE_RX_SERVER_NOTICES) str_append_c (out, 's');
}
static char *
client_get_mode (struct client *self)
{
struct str mode;
str_init (&mode);
if (self->away_message)
str_append_c (&mode, 'a');
client_mode_to_str (self->mode, &mode);
return str_steal (&mode);
}
#define IRC_SUPPORTED_CHAN_MODES "ov" "beI" "imnqpst" "kl"
enum
{
IRC_CHAN_MODE_INVITE_ONLY = (1 << 0),
IRC_CHAN_MODE_MODERATED = (1 << 1),
IRC_CHAN_MODE_NO_OUTSIDE_MSGS = (1 << 2),
IRC_CHAN_MODE_QUIET = (1 << 3),
IRC_CHAN_MODE_PRIVATE = (1 << 4),
IRC_CHAN_MODE_SECRET = (1 << 5),
IRC_CHAN_MODE_PROTECTED_TOPIC = (1 << 6),
IRC_CHAN_MODE_OPERATOR = (1 << 7),
IRC_CHAN_MODE_VOICE = (1 << 8)
};
struct channel_user
{
LIST_HEADER (channel_user)
unsigned modes;
char nickname[];
};
struct channel
{
struct server_context *ctx; ///< Server context
char *name; ///< Channel name
unsigned modes; ///< Channel modes
char *key; ///< Channel key
long user_limit; ///< User limit or -1
char *topic; ///< Channel topic
struct channel_user *users; ///< Channel users
struct str_vector ban_list; ///< Ban list
struct str_vector exception_list; ///< Exceptions from bans
struct str_vector invite_list; ///< Exceptions from +I
};
static void
channel_init (struct channel *self)
{
memset (self, 0, sizeof *self);
self->user_limit = -1;
self->topic = xstrdup ("");
str_vector_init (&self->ban_list);
str_vector_init (&self->exception_list);
str_vector_init (&self->invite_list);
}
static void
channel_free (struct channel *self)
{
free (self->name);
free (self->key);
free (self->topic);
struct channel_user *link, *tmp;
for (link = self->users; link; link = tmp)
{
tmp = link->next;
free (link);
}
str_vector_free (&self->ban_list);
str_vector_free (&self->exception_list);
str_vector_free (&self->invite_list);
}
static char *
channel_get_mode (struct channel *self, bool disclose_secrets)
{
struct str mode;
str_init (&mode);
unsigned m = self->modes;
if (m & IRC_CHAN_MODE_INVITE_ONLY) str_append_c (&mode, 'i');
if (m & IRC_CHAN_MODE_MODERATED) str_append_c (&mode, 'm');
if (m & IRC_CHAN_MODE_NO_OUTSIDE_MSGS) str_append_c (&mode, 'n');
if (m & IRC_CHAN_MODE_QUIET) str_append_c (&mode, 'q');
if (m & IRC_CHAN_MODE_PRIVATE) str_append_c (&mode, 'p');
if (m & IRC_CHAN_MODE_SECRET) str_append_c (&mode, 's');
if (m & IRC_CHAN_MODE_PROTECTED_TOPIC) str_append_c (&mode, 't');
if (self->user_limit != -1) str_append_c (&mode, 'l');
if (self->key) str_append_c (&mode, 'k');
if (self->user_limit != -1)
str_append_printf (&mode, " %ld", self->user_limit);
// XXX: is this correct? Try it on an existing implementation.
if (self->key && disclose_secrets)
str_append_printf (&mode, " %s", self->key);
return str_steal (&mode);
}
struct server_context
{
int listen_fd; ///< Listening socket FD
struct client *clients; ///< Clients
SSL_CTX *ssl_ctx; ///< SSL context
unsigned n_clients; ///< Current number of connections
struct str_map users; ///< Maps nicknames to clients
struct str_map channels; ///< Maps channel names to data
struct str_map handlers; ///< Message handlers
struct poller poller; ///< Manages polled description
bool quitting; ///< User requested quitting
bool polling; ///< The event loop is running
struct str_map config; ///< Server configuration
char *server_name; ///< Our server name
unsigned ping_interval; ///< Ping interval in seconds
unsigned max_connections; ///< Max. connections allowed or 0
struct str_vector motd; ///< MOTD (none if empty)
nl_catd catalog; ///< Message catalog for server msgs
};
static void
server_context_init (struct server_context *self)
{
self->listen_fd = -1;
self->clients = NULL;
self->n_clients = 0;
str_map_init (&self->users);
self->users.key_xfrm = irc_strxfrm;
// TODO: set channel_free() as the free function?
str_map_init (&self->channels);
self->channels.key_xfrm = irc_strxfrm;
str_map_init (&self->handlers);
self->handlers.key_xfrm = irc_strxfrm;
poller_init (&self->poller);
self->quitting = false;
self->polling = false;
str_map_init (&self->config);
self->config.free = free;
load_config_defaults (&self->config, g_config_table);
self->server_name = NULL;
self->ping_interval = 0;
self->max_connections = 0;
str_vector_init (&self->motd);
self->catalog = (nl_catd) -1;
}
static void
server_context_free (struct server_context *self)
{
str_map_free (&self->config);
if (self->listen_fd != -1)
xclose (self->listen_fd);
if (self->ssl_ctx)
SSL_CTX_free (self->ssl_ctx);
struct client *link, *tmp;
for (link = self->clients; link; link = tmp)
{
tmp = link->next;
client_free (link);
free (link);
}
free (self->server_name);
str_map_free (&self->users);
str_map_free (&self->channels);
str_map_free (&self->handlers);
poller_free (&self->poller);
str_vector_free (&self->motd);
if (self->catalog != (nl_catd) -1)
catclose (self->catalog);
}
static void
irc_try_finish_quit (struct server_context *ctx)
{
if (!ctx->n_clients && ctx->quitting)
ctx->polling = false;
}
static const char *
irc_get_text (struct server_context *ctx, int id, const char *def)
{
if (!soft_assert (def != NULL))
def = "";
if (ctx->catalog == (nl_catd) -1)
return def;
return catgets (ctx->catalog, 1, id, def);
}
static int
irc_fnmatch (const char *pattern, const char *string)
{
size_t pattern_size = strlen (pattern) + 1;
size_t string_size = strlen (string) + 1;
char x_pattern[pattern_size], x_string[string_size];
irc_strxfrm (x_pattern, pattern, pattern_size);
irc_strxfrm (x_string, string, string_size);
return fnmatch (x_pattern, x_string, 0);
}
// --- Channels ----------------------------------------------------------------
static struct channel_user *
channel_get_user (const struct channel *chan, const struct client *c)
{
for (struct channel_user *iter = chan->users; iter; iter = iter->next)
if (!irc_strcmp (iter->nickname, c->nickname))
return iter;
return NULL;
}
static struct channel_user *
channel_add_user (struct channel *chan, const struct client *c)
{
size_t nick_len = strlen (c->nickname);
struct channel_user *link = xcalloc (1, sizeof *link + nick_len + 1);
memcpy (link->nickname, c->nickname, nick_len + 1);
LIST_PREPEND (chan->users, link);
return link;
}
static void
channel_remove_user (struct channel *chan, struct channel_user *user)
{
LIST_UNLINK (chan->users, user);
free (user);
}
static size_t
channel_user_count (const struct channel *chan)
{
size_t result = 0;
for (struct channel_user *iter = chan->users; iter; iter = iter->next)
result++;
return result;
}
static struct channel *
channel_create (struct server_context *ctx, const char *name)
{
struct channel *chan = xcalloc (1, sizeof *chan);
channel_init (chan);
str_map_set (&ctx->channels, name, chan);
chan->ctx = ctx;
chan->name = xstrdup (name);
return chan;
}
static void
channel_destroy_if_empty (struct server_context *ctx, struct channel *chan)
{
if (!chan->users)
{
str_map_set (&ctx->channels, chan->name, NULL);
channel_free (chan);
free (chan);
}
}
// --- Clients -----------------------------------------------------------------
static void client_cancel_timers (struct client *);
static void client_set_kill_timer (struct client *);
static void client_update_poller (struct client *, const struct pollfd *);
static void
irc_send_str (struct client *c, const struct str *s)
{
hard_assert (c->initialized && !c->closing_link);
// TODO: kill the connection above some "SendQ" threshold (careful!)
str_append_data (&c->write_buffer, s->str,
s->len > IRC_MAX_MESSAGE_LENGTH ? IRC_MAX_MESSAGE_LENGTH : s->len);
str_append (&c->write_buffer, "\r\n");
// XXX: we might want to move this elsewhere, so that it doesn't get called
// as often; it's going to cause a lot of syscalls with epoll.
client_update_poller (c, NULL);
}
static void irc_send (struct client *c,
const char *format, ...) ATTRIBUTE_PRINTF (2, 3);
static void
irc_send (struct client *c, const char *format, ...)
{
struct str tmp;
str_init (&tmp);
va_list ap;
va_start (ap, format);
str_append_vprintf (&tmp, format, ap);
va_end (ap);
irc_send_str (c, &tmp);
str_free (&tmp);
}
static void
client_send_to_roommates (struct client *c, const char *message)
{
struct str_map targets;
str_map_init (&targets);
targets.key_xfrm = irc_strxfrm;
struct str_map_iter iter;
str_map_iter_init (&iter, &c->ctx->channels);
struct channel *chan;
while ((chan = str_map_iter_next (&iter)))
{
if (chan->modes & IRC_CHAN_MODE_QUIET
|| !channel_get_user (chan, c))
continue;
// When we're unregistering, the str_map_find() will return zero,
// which will prevent sending the QUIT message to ourselves.
for (struct channel_user *iter = chan->users; iter; iter = iter->next)
str_map_set (&targets, iter->nickname,
str_map_find (&c->ctx->users, iter->nickname));
}
str_map_iter_init (&iter, &targets);
struct client *target;
while ((target = str_map_iter_next (&iter)))
irc_send (target, "%s", message);
}
static void
client_unregister (struct client *c, const char *reason)
{
if (!c->registered)
return;
// Make the user effectively non-existent
str_map_set (&c->ctx->users, c->nickname, NULL);
char *message = xstrdup_printf (":%s!%s@%s QUIT :%s",
c->nickname, c->username, c->hostname, reason);
client_send_to_roommates (c, message);
free (message);
struct str_map_iter iter;
str_map_iter_init (&iter, &c->ctx->channels);
struct channel *chan;
while ((chan = str_map_iter_next (&iter)))
{
struct channel_user *user;
if (!(user = channel_get_user (chan, c)))
continue;
channel_remove_user (chan, user);
channel_destroy_if_empty (c->ctx, chan);
}
free (c->nickname);
c->nickname = NULL;
c->registered = false;
}
static void
client_kill (struct client *c, const char *reason)
{
client_unregister (c, reason ? reason : "Client exited");
struct server_context *ctx = c->ctx;
ssize_t i = poller_find_by_fd (&ctx->poller, c->socket_fd);
if (i != -1)
poller_remove_at_index (&ctx->poller, i);
client_cancel_timers (c);
if (c->ssl)
(void) SSL_shutdown (c->ssl);
xclose (c->socket_fd);
c->socket_fd = -1;
client_free (c);
LIST_UNLINK (ctx->clients, c);
ctx->n_clients--;
free (c);
irc_try_finish_quit (ctx);
}
static void
irc_close_link (struct client *c, const char *reason)
{
if (!soft_assert (!c->closing_link))
return;
// We push an `ERROR' message to the write buffer and let the poller send
// it, with some arbitrary timeout. The `closing_link' state makes sure
// that a/ we ignore any successive messages, and b/ that the connection
// is killed after the write buffer is transferred and emptied.
irc_send (c, "ERROR :Closing Link: %s[%s] (%s)", c->nickname,
c->hostname /* TODO host IP? */, reason);
c->closing_link = true;
client_unregister (c, reason);
client_set_kill_timer (c);
}
static bool
client_in_mask_list (const struct client *c, const struct str_vector *mask)
{
char *client = xstrdup_printf ("%s!%s@%s",
c->nickname, c->username, c->hostname);
bool result = false;
for (size_t i = 0; i < mask->len; i++)
if (!irc_fnmatch (client, mask->vector[i]))
{
result = true;
break;
}
free (client);
return result;
}
static void
irc_initiate_quit (struct server_context *ctx)
{
print_status ("shutting down");
for (struct client *iter = ctx->clients; iter; iter = iter->next)
if (!iter->closing_link)
irc_close_link (iter, "Shutting down");
ssize_t i = poller_find_by_fd (&ctx->poller, ctx->listen_fd);
if (soft_assert (i != -1))
poller_remove_at_index (&ctx->poller, i);
if (ctx->listen_fd != -1)
xclose (ctx->listen_fd);
ctx->listen_fd = -1;
ctx->quitting = true;
irc_try_finish_quit (ctx);
}
// --- Timers ------------------------------------------------------------------
static void
client_cancel_timers (struct client *c)
{
ssize_t i;
struct poller_timers *timers = &c->ctx->poller.timers;
while ((i = poller_timers_find_by_data (timers, c)) != -1)
poller_timers_remove_at_index (timers, i);
}
static void
client_set_timer (struct client *c, poller_timer_func fn, unsigned interval)
{
client_cancel_timers (c);
poller_timers_add (&c->ctx->poller.timers, fn, c, interval * 1000);
}
static void
on_irc_client_kill_timer (void *user_data)
{
struct client *c = user_data;
hard_assert (!c->initialized || c->closing_link);
client_kill (c, NULL);
}
static void
client_set_kill_timer (struct client *c)
{
client_set_timer (c, on_irc_client_kill_timer, c->ctx->ping_interval);
}
static void
on_irc_client_timeout_timer (void *user_data)
{
struct client *c = user_data;
char *reason = xstrdup_printf
("Ping timeout: >%u seconds", c->ctx->ping_interval);
irc_close_link (c, reason);
free (reason);
}
static void
on_irc_client_ping_timer (void *user_data)
{
struct client *c = user_data;
hard_assert (!c->closing_link);
irc_send (c, "PING :%s", c->ctx->server_name);
client_set_timer (c, on_irc_client_timeout_timer, c->ctx->ping_interval);
}
static void
client_set_ping_timer (struct client *c)
{
client_set_timer (c, on_irc_client_ping_timer, c->ctx->ping_interval);
}
// --- IRC command handling ----------------------------------------------------
enum
{
IRC_RPL_WELCOME = 1,
IRC_RPL_YOURHOST = 2,
IRC_RPL_CREATED = 3,
IRC_RPL_MYINFO = 4,
IRC_RPL_UMODEIS = 221,
IRC_RPL_LUSERCLIENT = 251,
IRC_RPL_LUSEROP = 252,
IRC_RPL_LUSERUNKNOWN = 253,
IRC_RPL_LUSERCHANNELS = 254,
IRC_RPL_LUSERME = 255,
IRC_RPL_AWAY = 301,
IRC_RPL_USERHOST = 302,
IRC_RPL_ISON = 303,
IRC_RPL_UNAWAY = 305,
IRC_RPL_NOWAWAY = 306,
IRC_RPL_WHOISUSER = 311,
IRC_RPL_WHOISSERVER = 312,
IRC_RPL_WHOISOPERATOR = 313,
IRC_RPL_ENDOFWHO = 315,
IRC_RPL_WHOISIDLE = 317,
IRC_RPL_ENDOFWHOIS = 318,
IRC_RPL_WHOISCHANNELS = 319,
IRC_RPL_LIST = 322,
IRC_RPL_LISTEND = 323,
IRC_RPL_CHANNELMODEIS = 324,
IRC_RPL_NOTOPIC = 331,
IRC_RPL_TOPIC = 332,
IRC_RPL_INVITELIST = 346,
IRC_RPL_ENDOFINVITELIST = 347,
IRC_RPL_EXCEPTLIST = 348,
IRC_RPL_ENDOFEXCEPTLIST = 349,
IRC_RPL_VERSION = 351,
IRC_RPL_WHOREPLY = 352,
IRC_RPL_NAMREPLY = 353,
IRC_RPL_ENDOFNAMES = 366,
IRC_RPL_BANLIST = 367,
IRC_RPL_ENDOFBANLIST = 368,
IRC_RPL_MOTD = 372,
IRC_RPL_MOTDSTART = 375,
IRC_RPL_ENDOFMOTD = 376,
IRC_RPL_TIME = 391,
IRC_ERR_NOSUCHNICK = 401,
IRC_ERR_NOSUCHSERVER = 402,
IRC_ERR_NOSUCHCHANNEL = 403,
IRC_ERR_CANNOTSENDTOCHAN = 404,
IRC_ERR_NOORIGIN = 409,
IRC_ERR_NORECIPIENT = 411,
IRC_ERR_NOTEXTTOSEND = 412,
IRC_ERR_UNKNOWNCOMMAND = 421,
IRC_ERR_NOMOTD = 422,
IRC_ERR_NONICKNAMEGIVEN = 431,
IRC_ERR_ERRONEOUSNICKNAME = 432,
IRC_ERR_NICKNAMEINUSE = 433,
IRC_ERR_USERNOTINCHANNEL = 441,
IRC_ERR_NOTONCHANNEL = 442,
IRC_ERR_SUMMONDISABLED = 445,
IRC_ERR_USERSDISABLED = 446,
IRC_ERR_NOTREGISTERED = 451,
IRC_ERR_NEEDMOREPARAMS = 461,
IRC_ERR_ALREADYREGISTERED = 462,
IRC_ERR_CHANNELISFULL = 471,
IRC_ERR_INVITEONLYCHAN = 473,
IRC_ERR_BANNEDFROMCHAN = 474,
IRC_ERR_BADCHANNELKEY = 475,
IRC_ERR_BADCHANMASK = 476,
IRC_ERR_NOPRIVILEGES = 481,
IRC_ERR_CHANOPRIVSNEEDED = 482,
IRC_ERR_UMODEUNKNOWNFLAG = 501,
IRC_ERR_USERSDONTMATCH = 502
};
static const char *g_default_replies[] =
{
[IRC_RPL_WELCOME] = ":Welcome to the Internet Relay Network %s!%s@%s",
[IRC_RPL_YOURHOST] = ":Your host is %s, running version %s",
[IRC_RPL_CREATED] = ":This server was created %s",
[IRC_RPL_MYINFO] = "%s %s %s %s",
[IRC_RPL_UMODEIS] = "+%s",
[IRC_RPL_LUSERCLIENT] = ":There are %d users and %d services on %d servers",
[IRC_RPL_LUSEROP] = "%d :operator(s) online",
[IRC_RPL_LUSERUNKNOWN] = "%d :unknown connection(s)",
[IRC_RPL_LUSERCHANNELS] = "%d :channels formed",
[IRC_RPL_LUSERME] = ":I have %d clients and %d servers",
[IRC_RPL_AWAY] = "%s :%s",
[IRC_RPL_USERHOST] = ":%s",
[IRC_RPL_ISON] = ":%s",
[IRC_RPL_UNAWAY] = ":You are no longer marked as being away",
[IRC_RPL_NOWAWAY] = ":You have been marked as being away",
[IRC_RPL_WHOISUSER] = "%s %s %s * :%s",
[IRC_RPL_WHOISSERVER] = "%s %s :%s",
[IRC_RPL_WHOISOPERATOR] = "%s :is an IRC operator",
[IRC_RPL_ENDOFWHO] = "%s :End of WHO list",
[IRC_RPL_WHOISIDLE] = "%s %d :seconds idle",
[IRC_RPL_ENDOFWHOIS] = "%s :End of WHOIS list",
[IRC_RPL_WHOISCHANNELS] = "%s :%s",
[IRC_RPL_LIST] = "%s %d :%s",
[IRC_RPL_LISTEND] = ":End of LIST",
[IRC_RPL_CHANNELMODEIS] = "%s +%s",
[IRC_RPL_NOTOPIC] = "%s :No topic is set",
[IRC_RPL_TOPIC] = "%s :%s",
[IRC_RPL_INVITELIST] = "%s %s",
[IRC_RPL_ENDOFINVITELIST] = "%s :End of channel invite list",
[IRC_RPL_EXCEPTLIST] = "%s %s",
[IRC_RPL_ENDOFEXCEPTLIST] = "%s :End of channel exception list",
[IRC_RPL_VERSION] = "%s.%d %s :%s",
[IRC_RPL_WHOREPLY] = "%s %s %s %s %s %s :%d %s",
[IRC_RPL_NAMREPLY] = "%c %s :%s",
[IRC_RPL_ENDOFNAMES] = "%s :End of NAMES list",
[IRC_RPL_BANLIST] = "%s %s",
[IRC_RPL_ENDOFBANLIST] = "%s :End of channel ban list",
[IRC_RPL_MOTD] = ":- %s",
[IRC_RPL_MOTDSTART] = ":- %s Message of the day - ",
[IRC_RPL_ENDOFMOTD] = ":End of MOTD command",
[IRC_RPL_TIME] = "%s :%s",
[IRC_ERR_NOSUCHNICK] = "%s :No such nick/channel",
[IRC_ERR_NOSUCHSERVER] = "%s :No such server",
[IRC_ERR_NOSUCHCHANNEL] = "%s :No such channel",
[IRC_ERR_CANNOTSENDTOCHAN] = "%s :Cannot send to channel",
[IRC_ERR_NOORIGIN] = ":No origin specified",
[IRC_ERR_NORECIPIENT] = ":No recipient given (%s)",
[IRC_ERR_NOTEXTTOSEND] = ":No text to send",
[IRC_ERR_UNKNOWNCOMMAND] = "%s: Unknown command",
[IRC_ERR_NOMOTD] = ":MOTD File is missing",
[IRC_ERR_NONICKNAMEGIVEN] = ":No nickname given",
[IRC_ERR_ERRONEOUSNICKNAME] = "%s :Erroneous nickname",
[IRC_ERR_NICKNAMEINUSE] = "%s :Nickname is already in use",
[IRC_ERR_USERNOTINCHANNEL] = "%s %s :They aren't on that channel",
[IRC_ERR_NOTONCHANNEL] = "%s :You're not on that channel",
[IRC_ERR_SUMMONDISABLED] = ":SUMMON has been disabled",
[IRC_ERR_USERSDISABLED] = ":USERS has been disabled",
[IRC_ERR_NOTREGISTERED] = ":You have not registered",
[IRC_ERR_NEEDMOREPARAMS] = "%s :Not enough parameters",
[IRC_ERR_ALREADYREGISTERED] = ":Unauthorized command (already registered)",
[IRC_ERR_CHANNELISFULL] = "%s :Cannot join channel (+l)",
[IRC_ERR_INVITEONLYCHAN] = "%s :Cannot join channel (+i)",
[IRC_ERR_BANNEDFROMCHAN] = "%s :Cannot join channel (+b)",
[IRC_ERR_BADCHANNELKEY] = "%s :Cannot join channel (+k)",
[IRC_ERR_BADCHANMASK] = "%s :Bad Channel Mask",
[IRC_ERR_NOPRIVILEGES] = ":Permission Denied- You're not an IRC operator",
[IRC_ERR_CHANOPRIVSNEEDED] = "%s :You're not channel operator",
[IRC_ERR_UMODEUNKNOWNFLAG] = ":Unknown MODE flag",
[IRC_ERR_USERSDONTMATCH] = ":Cannot change mode for other users",
};
// XXX: this way we cannot typecheck the arguments, so we must be careful
static void
irc_send_reply (struct client *c, int id, ...)
{
struct str tmp;
str_init (&tmp);
va_list ap;
va_start (ap, id);
str_append_printf (&tmp, ":%s %03d %s ",
c->ctx->server_name, id, c->nickname ? c->nickname : "");
str_append_vprintf (&tmp,
irc_get_text (c->ctx, id, g_default_replies[id]), ap);
va_end (ap);
irc_send_str (c, &tmp);
str_free (&tmp);
}
#define RETURN_WITH_REPLY(c, ...) \
BLOCK_START \
irc_send_reply ((c), __VA_ARGS__); \
return; \
BLOCK_END
static void
irc_send_motd (struct client *c)
{
struct server_context *ctx = c->ctx;
if (!ctx->motd.len)
RETURN_WITH_REPLY (c, IRC_ERR_NOMOTD);
irc_send_reply (c, IRC_RPL_MOTDSTART, ctx->server_name);
for (size_t i = 0; i < ctx->motd.len; i++)
irc_send_reply (c, IRC_RPL_MOTD, ctx->motd.vector[i]);
irc_send_reply (c, IRC_RPL_ENDOFMOTD);
}
static void
irc_send_lusers (struct client *c)
{
int n_users = 0, n_services = 0, n_opers = 0, n_unknown = 0;
for (struct client *link = c->ctx->clients; link; link = link->next)
{
if (link->registered)
n_users++;
else
n_unknown++;
if (link->mode & IRC_USER_MODE_OPERATOR)
n_opers++;
}
int n_channels = 0;
struct str_map_iter iter;
str_map_iter_init (&iter, &c->ctx->channels);
struct channel *chan;
while ((chan = str_map_iter_next (&iter)))
if (!(chan->modes & IRC_CHAN_MODE_SECRET)
|| channel_get_user (chan, c))
n_channels++;
irc_send_reply (c, IRC_RPL_LUSERCLIENT,
n_users, n_services, 1 /* servers total */);
if (n_opers)
irc_send_reply (c, IRC_RPL_LUSEROP, n_opers);
if (n_unknown)
irc_send_reply (c, IRC_RPL_LUSERUNKNOWN, n_unknown);
if (n_channels)
irc_send_reply (c, IRC_RPL_LUSERCHANNELS, n_channels);
irc_send_reply (c, IRC_RPL_LUSERME,
n_users + n_services + n_unknown, 0 /* peer servers */);
}
static bool
irc_is_this_me (struct server_context *ctx, const char *target)
{
// Target servers can also be matched by their users
return !irc_fnmatch (target, ctx->server_name)
|| str_map_find (&ctx->users, target);
}
static void
irc_try_finish_registration (struct client *c)
{
struct server_context *ctx = c->ctx;
if (!c->nickname || !c->username || !c->realname)
return;
c->registered = true;
irc_send_reply (c, IRC_RPL_WELCOME, c->nickname, c->username, c->hostname);
irc_send_reply (c, IRC_RPL_YOURHOST, ctx->server_name, PROGRAM_VERSION);
// The purpose of this message eludes me
irc_send_reply (c, IRC_RPL_CREATED, __DATE__);
irc_send_reply (c, IRC_RPL_MYINFO, ctx->server_name, PROGRAM_VERSION,
IRC_SUPPORTED_USER_MODES, IRC_SUPPORTED_CHAN_MODES);
irc_send_lusers (c);
irc_send_motd (c);
char *mode = client_get_mode (c);
if (*mode)
irc_send (c, ":%s MODE %s :+%s", c->nickname, c->nickname, mode);
free (mode);
}
static void
irc_handle_pass (const struct irc_message *msg, struct client *c)
{
if (c->registered)
irc_send_reply (c, IRC_ERR_ALREADYREGISTERED);
else if (msg->params.len < 1)
irc_send_reply (c, IRC_ERR_NEEDMOREPARAMS, msg->command);
// We have SSL client certificates for this purpose; ignoring
}
static void
irc_handle_nick (const struct irc_message *msg, struct client *c)
{
struct server_context *ctx = c->ctx;
if (msg->params.len < 1)
RETURN_WITH_REPLY (c, IRC_ERR_NONICKNAMEGIVEN);
const char *nickname = msg->params.vector[0];
if (irc_validate_nickname (nickname) != VALIDATION_OK)
RETURN_WITH_REPLY (c, IRC_ERR_ERRONEOUSNICKNAME, nickname);
struct client *client = str_map_find (&ctx->users, nickname);
if (client && client != c)
RETURN_WITH_REPLY (c, IRC_ERR_NICKNAMEINUSE, nickname);
if (c->registered)
{
char *message = xstrdup_printf (":%s!%s@%s NICK :%s",
c->nickname, c->username, c->hostname, nickname);
client_send_to_roommates (c, message);
free (message);
}
// Release the old nickname and allocate a new one
if (c->nickname)
{
str_map_set (&ctx->users, c->nickname, NULL);
free (c->nickname);
}
c->nickname = xstrdup (nickname);
str_map_set (&ctx->users, nickname, c);
if (!c->registered)
irc_try_finish_registration (c);
}
static void
irc_handle_user (const struct irc_message *msg, struct client *c)
{
if (c->registered)
RETURN_WITH_REPLY (c, IRC_ERR_ALREADYREGISTERED);
if (msg->params.len < 4)
RETURN_WITH_REPLY (c, IRC_ERR_NEEDMOREPARAMS, msg->command);
const char *username = msg->params.vector[0];
const char *mode = msg->params.vector[1];
const char *realname = msg->params.vector[3];
// Unfortunately the protocol doesn't give us any means of rejecting it
if (!irc_is_valid_user (username))
username = "xxx";
free (c->username);
c->username = xstrdup (username);
free (c->realname);
c->realname = xstrdup (realname);
unsigned long m;
if (xstrtoul (&m, mode, 10))
{
if (m & 4) c->mode |= IRC_USER_MODE_RX_WALLOPS;
if (m & 8) c->mode |= IRC_USER_MODE_INVISIBLE;
}
irc_try_finish_registration (c);
}
static void
irc_handle_userhost (const struct irc_message *msg, struct client *c)
{
if (msg->params.len < 1)
RETURN_WITH_REPLY (c, IRC_ERR_NEEDMOREPARAMS, msg->command);
struct str reply;
str_init (&reply);
for (size_t i = 0; i < 5 && i < msg->params.len; i++)
{
const char *nick = msg->params.vector[i];
struct client *target = str_map_find (&c->ctx->users, nick);
if (!target)
continue;
if (i)
str_append_c (&reply, ' ');
str_append (&reply, nick);
if (target->mode & IRC_USER_MODE_OPERATOR)
str_append_c (&reply, '*');
str_append_printf (&reply, "=%c%s@%s",
target->away_message ? '-' : '+',
target->username, target->hostname);
}
irc_send_reply (c, IRC_RPL_USERHOST, reply.str);
str_free (&reply);
}
static void
irc_handle_lusers (const struct irc_message *msg, struct client *c)
{
if (msg->params.len > 1 && !irc_is_this_me (c->ctx, msg->params.vector[1]))
irc_send_reply (c, IRC_ERR_NOSUCHSERVER, msg->params.vector[1]);
else
irc_send_lusers (c);
}
static void
irc_handle_motd (const struct irc_message *msg, struct client *c)
{
if (msg->params.len > 0 && !irc_is_this_me (c->ctx, msg->params.vector[0]))
irc_send_reply (c, IRC_ERR_NOSUCHSERVER, msg->params.vector[0]);
else
irc_send_motd (c);
}
static void
irc_handle_ping (const struct irc_message *msg, struct client *c)
{
// XXX: the RFC is pretty incomprehensible about the exact usage
if (msg->params.len > 1 && !irc_is_this_me (c->ctx, msg->params.vector[1]))
irc_send_reply (c, IRC_ERR_NOSUCHSERVER, msg->params.vector[1]);
else if (msg->params.len < 1)
irc_send_reply (c, IRC_ERR_NOORIGIN);
else
irc_send (c, ":%s PONG :%s",
c->ctx->server_name, msg->params.vector[0]);
}
static void
irc_handle_pong (const struct irc_message *msg, struct client *c)
{
// We are the only server, so we don't have to care too much
if (msg->params.len < 1)
irc_send_reply (c, IRC_ERR_NOORIGIN);
else
// Set a new timer to send another PING
client_set_ping_timer (c);
}
static void
irc_handle_quit (const struct irc_message *msg, struct client *c)
{
char *reason = xstrdup_printf ("Quit: %s",
msg->params.len > 0 ? msg->params.vector[0] : c->nickname);
irc_close_link (c, reason);
free (reason);
}
static void
irc_handle_time (const struct irc_message *msg, struct client *c)
{
if (msg->params.len > 0 && !irc_is_this_me (c->ctx, msg->params.vector[0]))
RETURN_WITH_REPLY (c, IRC_ERR_NOSUCHSERVER, msg->params.vector[0]);
char buf[32];
time_t now = time (NULL);
struct tm tm;
strftime (buf, sizeof buf, "%a %b %d %Y %T", localtime_r (&now, &tm));
irc_send_reply (c, IRC_RPL_TIME, c->ctx->server_name, buf);
}
static void
irc_handle_version (const struct irc_message *msg, struct client *c)
{
if (msg->params.len > 0 && !irc_is_this_me (c->ctx, msg->params.vector[0]))
irc_send_reply (c, IRC_ERR_NOSUCHSERVER, msg->params.vector[0]);
else
irc_send_reply (c, IRC_RPL_VERSION, PROGRAM_VERSION, g_debug_mode,
c->ctx->server_name, PROGRAM_NAME " " PROGRAM_VERSION);
}
static void
irc_channel_multicast (struct channel *chan, const char *message,
struct client *except)
{
for (struct channel_user *iter = chan->users; iter; iter = iter->next)
{
struct client *c = str_map_find (&chan->ctx->users, iter->nickname);
if (c != except)
irc_send (c, "%s", message);
}
}
static void
irc_send_channel_list (struct client *c, const char *channel_name,
const struct str_vector *list, int reply, int end_reply)
{
for (size_t i = 0; i < list->len; i++)
irc_send_reply (c, reply, channel_name, list->vector[i]);
irc_send_reply (c, end_reply);
}
static bool
irc_maybe_send_channel_list (struct client *c, struct channel *chan,
const char *mode_string)
{
if (*mode_string == '+')
mode_string++;
if (!strcmp (mode_string, "b"))
irc_send_channel_list (c, chan->name, &chan->ban_list,
IRC_RPL_BANLIST, IRC_RPL_ENDOFBANLIST);
else if (!strcmp (mode_string, "e"))
irc_send_channel_list (c, chan->name, &chan->exception_list,
IRC_RPL_EXCEPTLIST, IRC_RPL_ENDOFEXCEPTLIST);
else if (!strcmp (mode_string, "I"))
irc_send_channel_list (c, chan->name, &chan->invite_list,
IRC_RPL_INVITELIST, IRC_RPL_ENDOFINVITELIST);
else
return false;
return true;
}
static void
irc_modify_mode (unsigned *mask, unsigned mode, bool add)
{
if (add)
*mask |= mode;
else
*mask &= ~mode;
}
static void
irc_update_user_mode (struct client *c, unsigned new_mode)
{
unsigned old_mode = c->mode;
c->mode = new_mode;
unsigned added = new_mode & ~old_mode;
unsigned removed = old_mode & ~new_mode;
struct str diff;
str_init (&diff);
if (added)
{
str_append_c (&diff, '+');
client_mode_to_str (added, &diff);
}
if (removed)
{
str_append_c (&diff, '-');
client_mode_to_str (removed, &diff);
}
if (diff.len)
irc_send (c, ":%s MODE %s :%s",
c->nickname, c->nickname, diff.str);
str_free (&diff);
}
static void
irc_handle_user_mode_change (struct client *c, const char *mode_string)
{
unsigned new_mode = c->mode;
bool adding = true;
while (*mode_string)
switch (*mode_string++)
{
case '+': adding = true; break;
case '-': adding = false; break;
case 'a':
// Ignore, the client should use AWAY
break;
case 'i':
irc_modify_mode (&new_mode, IRC_USER_MODE_INVISIBLE, adding);
break;
case 'w':
irc_modify_mode (&new_mode, IRC_USER_MODE_RX_WALLOPS, adding);
break;
case 'r':
if (adding)
irc_modify_mode (&new_mode, IRC_USER_MODE_RESTRICTED, true);
break;
case 'o':
if (!adding)
irc_modify_mode (&new_mode, IRC_USER_MODE_OPERATOR, false);
// TODO: check public key fingerprint when adding
break;
case 's':
irc_modify_mode (&new_mode, IRC_USER_MODE_RX_SERVER_NOTICES, adding);
break;
default:
RETURN_WITH_REPLY (c, IRC_ERR_UMODEUNKNOWNFLAG);
}
irc_update_user_mode (c, new_mode);
}
static void
irc_handle_mode (const struct irc_message *msg, struct client *c)
{
if (msg->params.len < 1)
RETURN_WITH_REPLY (c, IRC_ERR_NEEDMOREPARAMS, msg->command);
const char *target = msg->params.vector[0];
struct client *client = str_map_find (&c->ctx->users, target);
if (client)
{
if (irc_strcmp (target, c->nickname))
RETURN_WITH_REPLY (c, IRC_ERR_USERSDONTMATCH);
if (msg->params.len < 2)
{
char *mode = client_get_mode (client);
irc_send_reply (c, IRC_RPL_UMODEIS, mode);
free (mode);
}
else
irc_handle_user_mode_change (c, msg->params.vector[1]);
return;
}
struct channel *chan = str_map_find (&c->ctx->channels, target);
if (chan)
{
if (msg->params.len < 2)
{
char *mode = channel_get_mode (chan, channel_get_user (chan, c));
irc_send_reply (c, IRC_RPL_CHANNELMODEIS, target, mode);
free (mode);
return;
}
if (msg->params.len < 3
&& irc_maybe_send_channel_list (c, chan, msg->params.vector[1]))
return;
// TODO: mode modification
return;
}
irc_send_reply (c, IRC_ERR_NOSUCHNICK, target);
}
static void
irc_handle_user_message (const struct irc_message *msg, struct client *c,
const char *command, bool allow_away_reply)
{
if (msg->params.len < 1)
RETURN_WITH_REPLY (c, IRC_ERR_NORECIPIENT, msg->command);
if (msg->params.len < 2 || !*msg->params.vector[1])
RETURN_WITH_REPLY (c, IRC_ERR_NOTEXTTOSEND);
const char *target = msg->params.vector[0];
const char *text = msg->params.vector[1];
struct client *client = str_map_find (&c->ctx->users, target);
if (client)
{
irc_send (client, ":%s!%s@%s %s %s :%s",
c->nickname, c->username, c->hostname, command, target, text);
if (allow_away_reply && client->away_message)
irc_send_reply (c, IRC_RPL_AWAY, target, client->away_message);
return;
}
struct channel *chan = str_map_find (&c->ctx->channels, target);
if (chan)
{
struct channel_user *user = channel_get_user (chan, c);
if ((chan->modes & IRC_CHAN_MODE_NO_OUTSIDE_MSGS) && !user)
RETURN_WITH_REPLY (c, IRC_ERR_CANNOTSENDTOCHAN, target);
if ((chan->modes & IRC_CHAN_MODE_MODERATED) && (!user ||
!(user->modes & (IRC_CHAN_MODE_VOICE | IRC_CHAN_MODE_OPERATOR))))
RETURN_WITH_REPLY (c, IRC_ERR_CANNOTSENDTOCHAN, target);
if (client_in_mask_list (c, &chan->ban_list)
&& !client_in_mask_list (c, &chan->exception_list))
RETURN_WITH_REPLY (c, IRC_ERR_CANNOTSENDTOCHAN, target);
char *message = xstrdup_printf (":%s!%s@%s %s %s :%s",
c->nickname, c->username, c->hostname, command, target, text);
irc_channel_multicast (chan, message, c);
free (message);
return;
}
irc_send_reply (c, IRC_ERR_NOSUCHNICK, target);
}
static void
irc_handle_privmsg (const struct irc_message *msg, struct client *c)
{
irc_handle_user_message (msg, c, "PRIVMSG", true);
// Let's not care too much about success or failure
c->last_active = time (NULL);
}
static void
irc_handle_notice (const struct irc_message *msg, struct client *c)
{
irc_handle_user_message (msg, c, "NOTICE", false);
}
static void
irc_send_rpl_list (struct client *c, const struct channel *chan)
{
int visible = 0;
for (struct channel_user *user = chan->users;
user; user = user->next)
visible++;
irc_send_reply (c, IRC_RPL_LIST, chan->name, visible, chan->topic);
}
static void
irc_handle_list (const struct irc_message *msg, struct client *c)
{
if (msg->params.len > 1 && !irc_is_this_me (c->ctx, msg->params.vector[1]))
RETURN_WITH_REPLY (c, IRC_ERR_NOSUCHSERVER, msg->params.vector[1]);
struct channel *chan;
if (msg->params.len == 0)
{
struct str_map_iter iter;
str_map_iter_init (&iter, &c->ctx->channels);
while ((chan = str_map_iter_next (&iter)))
if (!(chan->modes & (IRC_CHAN_MODE_PRIVATE | IRC_CHAN_MODE_SECRET))
|| channel_get_user (chan, c))
irc_send_rpl_list (c, chan);
}
else
{
struct str_vector channels;
str_vector_init (&channels);
split_str_ignore_empty (msg->params.vector[0], ',', &channels);
for (size_t i = 0; i < channels.len; i++)
if ((chan = str_map_find (&c->ctx->channels, channels.vector[i]))
&& (!(chan->modes & IRC_CHAN_MODE_SECRET)
|| channel_get_user (chan, c)))
irc_send_rpl_list (c, chan);
str_vector_free (&channels);
}
irc_send_reply (c, IRC_RPL_LISTEND);
}
static void
irc_send_rpl_namreply (struct client *c, const struct channel *chan)
{
struct str_vector nicks;
str_vector_init (&nicks);
char type = '=';
if (chan->modes & IRC_CHAN_MODE_SECRET)
type = '@';
else if (chan->modes & IRC_CHAN_MODE_PRIVATE)
type = '*';
bool on_channel = channel_get_user (chan, c);
for (struct channel_user *iter = chan->users; iter; iter = iter->next)
{
struct client *target = str_map_find (&c->ctx->users, iter->nickname);
if (!on_channel && (target->mode & IRC_USER_MODE_INVISIBLE))
continue;
struct str result;
str_init (&result);
if (iter->modes & IRC_CHAN_MODE_OPERATOR)
str_append_c (&result, '@');
else if (iter->modes & IRC_CHAN_MODE_VOICE)
str_append_c (&result, '+');
str_append (&result, target->nickname);
str_vector_add_owned (&nicks, str_steal (&result));
}
if (nicks.len)
{
char *reply = join_str_vector (&nicks, ' ');
irc_send_reply (c, IRC_RPL_NAMREPLY, type, chan->name, reply);
free (reply);
}
str_vector_free (&nicks);
}
static void
irc_handle_names (const struct irc_message *msg, struct client *c)
{
if (msg->params.len > 1 && !irc_is_this_me (c->ctx, msg->params.vector[1]))
RETURN_WITH_REPLY (c, IRC_ERR_NOSUCHSERVER, msg->params.vector[1]);
struct channel *chan;
if (msg->params.len == 0)
{
struct str_map_iter iter;
str_map_iter_init (&iter, &c->ctx->channels);
while ((chan = str_map_iter_next (&iter)))
if (!(chan->modes & (IRC_CHAN_MODE_PRIVATE | IRC_CHAN_MODE_SECRET))
|| channel_get_user (chan, c))
irc_send_rpl_namreply (c, chan);
// TODO
// If no <channel> parameter is given, a list of all channels and their
// occupants is returned. At the end of this list, a list of users who
// are visible but either not on any channel or not on a visible channel
// are listed as being on `channel' "*".
irc_send_reply (c, IRC_RPL_ENDOFNAMES, "*");
}
else
{
struct str_vector channels;
str_vector_init (&channels);
split_str_ignore_empty (msg->params.vector[0], ',', &channels);
for (size_t i = 0; i < channels.len; i++)
if ((chan = str_map_find (&c->ctx->channels, channels.vector[i]))
&& (!(chan->modes & IRC_CHAN_MODE_SECRET)
|| channel_get_user (chan, c)))
{
irc_send_rpl_namreply (c, chan);
irc_send_reply (c, IRC_RPL_ENDOFNAMES, channels.vector[i]);
}
str_vector_free (&channels);
}
}
static void
irc_send_rpl_whoreply (struct client *c, const struct channel *chan,
const struct client *target)
{
struct str chars;
str_init (&chars);
str_append_c (&chars, target->away_message ? 'G' : 'H');
if (target->mode & IRC_USER_MODE_OPERATOR)
str_append_c (&chars, '*');
struct channel_user *user;
if (chan && (user = channel_get_user (chan, target)))
{
if (user->modes & IRC_CHAN_MODE_OPERATOR)
str_append_c (&chars, '@');
else if (user->modes & IRC_CHAN_MODE_VOICE)
str_append_c (&chars, '+');
}
irc_send_reply (c, IRC_RPL_WHOREPLY, chan ? chan->name : "*",
target->username, target->hostname, target->ctx->server_name,
target->nickname, chars.str, 0 /* hop count */, target->realname);
str_free (&chars);
}
static void
irc_match_send_rpl_whoreply (struct client *c, struct client *target,
const char *mask)
{
bool is_roommate = false;
struct str_map_iter iter;
str_map_iter_init (&iter, &c->ctx->channels);
struct channel *chan;
while ((chan = str_map_iter_next (&iter)))
if (channel_get_user (chan, target) && channel_get_user (chan, c))
{
is_roommate = true;
break;
}
if ((target->mode & IRC_USER_MODE_INVISIBLE) && !is_roommate)
return;
if (irc_fnmatch (mask, target->hostname)
&& irc_fnmatch (mask, target->nickname)
&& irc_fnmatch (mask, target->realname)
&& irc_fnmatch (mask, c->ctx->server_name))
return;
// Try to find a channel they're on that's visible to us
struct channel *user_chan = NULL;
str_map_iter_init (&iter, &c->ctx->channels);
while ((chan = str_map_iter_next (&iter)))
if (channel_get_user (chan, target)
&& (!(chan->modes & (IRC_CHAN_MODE_PRIVATE | IRC_CHAN_MODE_SECRET))
|| channel_get_user (chan, c)))
{
user_chan = chan;
break;
}
irc_send_rpl_whoreply (c, user_chan, target);
}
static void
irc_handle_who (const struct irc_message *msg, struct client *c)
{
bool only_ops = msg->params.len > 1 && !strcmp (msg->params.vector[1], "o");
const char *shown_mask = msg->params.vector[0], *used_mask;
if (!shown_mask)
used_mask = shown_mask = "*";
else if (!strcmp (shown_mask, "0"))
used_mask = "*";
else
used_mask = shown_mask;
struct channel *chan;
if ((chan = str_map_find (&c->ctx->channels, used_mask)))
{
bool on_chan = !!channel_get_user (chan, c);
if (on_chan || !(chan->modes & IRC_CHAN_MODE_SECRET))
for (struct channel_user *iter = chan->users;
iter; iter = iter->next)
{
struct client *target =
str_map_find (&c->ctx->users, iter->nickname);
if ((on_chan || !(target->mode & IRC_USER_MODE_INVISIBLE))
&& (!only_ops || (target->mode & IRC_USER_MODE_OPERATOR)))
irc_send_rpl_whoreply (c, chan, target);
}
}
else
{
struct str_map_iter iter;
str_map_iter_init (&iter, &c->ctx->users);
struct client *target;
while ((target = str_map_iter_next (&iter)))
if (!only_ops || (target->mode & IRC_USER_MODE_OPERATOR))
irc_match_send_rpl_whoreply (c, target, used_mask);
}
irc_send_reply (c, IRC_RPL_ENDOFWHO, shown_mask);
}
static void
irc_send_whois_reply (struct client *c, const struct client *target)
{
const char *nick = target->nickname;
irc_send_reply (c, IRC_RPL_WHOISUSER, nick, target->username,
target->hostname, target->realname);
irc_send_reply (c, IRC_RPL_WHOISSERVER, nick, target->ctx->server_name,
str_map_find (&c->ctx->config, "server_info"));
if (target->mode & IRC_USER_MODE_OPERATOR)
irc_send_reply (c, IRC_RPL_WHOISOPERATOR, nick);
irc_send_reply (c, IRC_RPL_WHOISIDLE, nick,
(int) (time (NULL) - target->last_active));
struct str_map_iter iter;
str_map_iter_init (&iter, &c->ctx->channels);
struct channel *chan;
struct channel_user *channel_user;
while ((chan = str_map_iter_next (&iter)))
if ((channel_user = channel_get_user (chan, target))
&& (!(chan->modes & (IRC_CHAN_MODE_PRIVATE | IRC_CHAN_MODE_SECRET))
|| channel_get_user (chan, c)))
{
struct str item;
str_init (&item);
if (channel_user->modes & IRC_CHAN_MODE_OPERATOR)
str_append_c (&item, '@');
else if (channel_user->modes & IRC_CHAN_MODE_VOICE)
str_append_c (&item, '+');
str_append (&item, chan->name);
str_append_c (&item, ' ');
// TODO: try to merge the results into as few messages as possible
irc_send_reply (c, IRC_RPL_WHOISCHANNELS, nick, item.str);
str_free (&item);
}
irc_send_reply (c, IRC_RPL_ENDOFWHOIS, nick);
}
static void
irc_handle_whois (const struct irc_message *msg, struct client *c)
{
if (msg->params.len < 1)
RETURN_WITH_REPLY (c, IRC_ERR_NEEDMOREPARAMS, msg->command);
if (msg->params.len > 1 && !irc_is_this_me (c->ctx, msg->params.vector[0]))
RETURN_WITH_REPLY (c, IRC_ERR_NOSUCHSERVER, msg->params.vector[0]);
struct str_vector masks;
str_vector_init (&masks);
const char *masks_str = msg->params.vector[msg->params.len > 1];
split_str_ignore_empty (masks_str, ',', &masks);
for (size_t i = 0; i < masks.len; i++)
{
const char *mask = masks.vector[i];
struct client *target;
if (!strpbrk (mask, "*?"))
{
if (!(target = str_map_find (&c->ctx->users, mask)))
irc_send_reply (c, IRC_ERR_NOSUCHNICK, mask);
else
irc_send_whois_reply (c, target);
}
else
{
struct str_map_iter iter;
str_map_iter_init (&iter, &c->ctx->users);
bool found = false;
while ((target = str_map_iter_next (&iter))
&& !irc_fnmatch (mask, target->nickname))
{
irc_send_whois_reply (c, target);
found = true;
}
if (!found)
irc_send_reply (c, IRC_ERR_NOSUCHNICK, mask);
}
}
str_vector_free (&masks);
}
static void
irc_send_rpl_topic (struct client *c, struct channel *chan)
{
if (!*chan->topic)
irc_send_reply (c, IRC_RPL_NOTOPIC, chan->name);
else
irc_send_reply (c, IRC_RPL_TOPIC, chan->name, chan->topic);
}
static void
irc_handle_topic (const struct irc_message *msg, struct client *c)
{
if (msg->params.len < 1)
RETURN_WITH_REPLY (c, IRC_ERR_NEEDMOREPARAMS, msg->command);
const char *target = msg->params.vector[0];
struct channel *chan = str_map_find (&c->ctx->channels, target);
if (!chan)
RETURN_WITH_REPLY (c, IRC_ERR_NOSUCHCHANNEL, target);
if (msg->params.len < 2)
{
irc_send_rpl_topic (c, chan);
return;
}
struct channel_user *user = channel_get_user (chan, c);
if (!user)
RETURN_WITH_REPLY (c, IRC_ERR_NOTONCHANNEL, target);
if ((chan->modes & IRC_CHAN_MODE_PROTECTED_TOPIC)
&& !(user->modes & IRC_CHAN_MODE_OPERATOR))
RETURN_WITH_REPLY (c, IRC_ERR_CHANOPRIVSNEEDED, target);
free (chan->topic);
chan->topic = xstrdup (msg->params.vector[1]);
char *message = xstrdup_printf (":%s!%s@%s TOPIC %s :%s",
c->nickname, c->username, c->hostname, target, chan->topic);
irc_channel_multicast (chan, message, NULL);
free (message);
}
static void
irc_try_part (struct client *c, const char *channel_name, const char *reason)
{
if (!reason)
reason = c->nickname;
struct channel *chan;
if (!(chan = str_map_find (&c->ctx->channels, channel_name)))
RETURN_WITH_REPLY (c, IRC_ERR_NOSUCHCHANNEL, channel_name);
struct channel_user *user;
if (!(user = channel_get_user (chan, c)))
RETURN_WITH_REPLY (c, IRC_ERR_NOTONCHANNEL, channel_name);
char *message = xstrdup_printf (":%s!%s@%s PART %s :%s",
c->nickname, c->username, c->hostname, channel_name, reason);
if (!(chan->modes & IRC_CHAN_MODE_QUIET))
irc_channel_multicast (chan, message, NULL);
else
irc_send (c, "%s", message);
free (message);
channel_remove_user (chan, user);
channel_destroy_if_empty (c->ctx, chan);
}
static void
irc_part_all_channels (struct client *c)
{
struct str_map_iter iter;
str_map_iter_init (&iter, &c->ctx->channels);
struct channel *chan = str_map_iter_next (&iter), *next;
while (chan)
{
// We have to be careful here, the channel might get destroyed
next = str_map_iter_next (&iter);
if (channel_get_user (chan, c))
irc_try_part (c, chan->name, NULL);
chan = next;
}
}
static void
irc_handle_part (const struct irc_message *msg, struct client *c)
{
if (msg->params.len < 1)
RETURN_WITH_REPLY (c, IRC_ERR_NEEDMOREPARAMS, msg->command);
const char *reason = msg->params.len > 1 ? msg->params.vector[1] : NULL;
struct str_vector channels;
str_vector_init (&channels);
split_str_ignore_empty (msg->params.vector[0], ',', &channels);
for (size_t i = 0; i < channels.len; i++)
irc_try_part (c, channels.vector[i], reason);
str_vector_free (&channels);
}
static void
irc_try_kick (struct client *c, const char *channel_name, const char *nick,
const char *reason)
{
struct channel *chan;
if (!(chan = str_map_find (&c->ctx->channels, channel_name)))
RETURN_WITH_REPLY (c, IRC_ERR_NOSUCHCHANNEL, channel_name);
struct channel_user *user;
if (!(user = channel_get_user (chan, c)))
RETURN_WITH_REPLY (c, IRC_ERR_NOTONCHANNEL, channel_name);
if (!(user->modes & IRC_CHAN_MODE_OPERATOR))
RETURN_WITH_REPLY (c, IRC_ERR_CHANOPRIVSNEEDED, channel_name);
struct client *client;
if (!(client = str_map_find (&c->ctx->users, nick))
|| !(user = channel_get_user (chan, client)))
RETURN_WITH_REPLY (c, IRC_ERR_USERNOTINCHANNEL, nick, channel_name);
char *message = xstrdup_printf (":%s!%s@%s KICK %s %s :%s",
c->nickname, c->username, c->hostname, channel_name, nick, reason);
if (!(chan->modes & IRC_CHAN_MODE_QUIET))
irc_channel_multicast (chan, message, NULL);
else
irc_send (c, "%s", message);
free (message);
channel_remove_user (chan, user);
channel_destroy_if_empty (c->ctx, chan);
}
static void
irc_handle_kick (const struct irc_message *msg, struct client *c)
{
if (msg->params.len < 2)
RETURN_WITH_REPLY (c, IRC_ERR_NEEDMOREPARAMS, msg->command);
const char *reason = c->nickname;
if (msg->params.len > 2)
reason = msg->params.vector[2];
struct str_vector channels;
struct str_vector users;
str_vector_init (&channels);
str_vector_init (&users);
split_str_ignore_empty (msg->params.vector[0], ',', &channels);
split_str_ignore_empty (msg->params.vector[1], ',', &users);
if (channels.len == 1)
for (size_t i = 0; i < users.len; i++)
irc_try_kick (c, channels.vector[0], users.vector[i], reason);
else
for (size_t i = 0; i < channels.len && i < users.len; i++)
irc_try_kick (c, channels.vector[i], users.vector[i], reason);
str_vector_free (&channels);
str_vector_free (&users);
}
static void
irc_try_join (struct client *c, const char *channel_name, const char *key)
{
struct channel *chan = str_map_find (&c->ctx->channels, channel_name);
unsigned user_mode = 0;
if (!chan)
{
if (irc_validate_channel_name (channel_name) != VALIDATION_OK)
RETURN_WITH_REPLY (c, IRC_ERR_BADCHANMASK, channel_name);
chan = channel_create (c->ctx, channel_name);
user_mode = IRC_CHAN_MODE_OPERATOR;
}
else if (channel_get_user (chan, c))
return;
if ((chan->modes & IRC_CHAN_MODE_INVITE_ONLY)
&& !client_in_mask_list (c, &chan->invite_list))
// TODO: exceptions caused by INVITE
RETURN_WITH_REPLY (c, IRC_ERR_INVITEONLYCHAN, channel_name);
if (chan->key && (!key || strcmp (key, chan->key)))
RETURN_WITH_REPLY (c, IRC_ERR_BADCHANNELKEY, channel_name);
if (chan->user_limit != -1
&& channel_user_count (chan) >= (size_t) chan->user_limit)
RETURN_WITH_REPLY (c, IRC_ERR_CHANNELISFULL, channel_name);
if (client_in_mask_list (c, &chan->ban_list)
&& !client_in_mask_list (c, &chan->exception_list))
RETURN_WITH_REPLY (c, IRC_ERR_BANNEDFROMCHAN, channel_name);
channel_add_user (chan, c)->modes = user_mode;
char *message = xstrdup_printf (":%s!%s@%s JOIN %s",
c->nickname, c->username, c->hostname, channel_name);
if (!(chan->modes & IRC_CHAN_MODE_QUIET))
irc_channel_multicast (chan, message, NULL);
else
irc_send (c, "%s", message);
free (message);
irc_send_rpl_topic (c, chan);
irc_send_rpl_namreply (c, chan);
irc_send_reply (c, IRC_RPL_ENDOFNAMES, chan->name);
}
static void
irc_handle_join (const struct irc_message *msg, struct client *c)
{
if (msg->params.len < 1)
RETURN_WITH_REPLY (c, IRC_ERR_NEEDMOREPARAMS, msg->command);
if (!strcmp (msg->params.vector[0], "0"))
{
irc_part_all_channels (c);
return;
}
struct str_vector channels;
struct str_vector keys;
str_vector_init (&channels);
str_vector_init (&keys);
split_str_ignore_empty (msg->params.vector[0], ',', &channels);
if (msg->params.len > 1)
split_str_ignore_empty (msg->params.vector[1], ',', &keys);
for (size_t i = 0; i < channels.len; i++)
irc_try_join (c, channels.vector[i],
i < keys.len ? keys.vector[i] : NULL);
str_vector_free (&channels);
str_vector_free (&keys);
}
static void
irc_handle_summon (const struct irc_message *msg, struct client *c)
{
(void) msg;
irc_send_reply (c, IRC_ERR_SUMMONDISABLED);
}
static void
irc_handle_users (const struct irc_message *msg, struct client *c)
{
(void) msg;
irc_send_reply (c, IRC_ERR_USERSDISABLED);
}
static void
irc_handle_away (const struct irc_message *msg, struct client *c)
{
if (msg->params.len < 1)
{
free (c->away_message);
c->away_message = NULL;
irc_send_reply (c, IRC_RPL_UNAWAY);
}
else
{
free (c->away_message);
c->away_message = xstrdup (msg->params.vector[0]);
irc_send_reply (c, IRC_RPL_NOWAWAY);
}
}
static void
irc_handle_ison (const struct irc_message *msg, struct client *c)
{
if (msg->params.len < 1)
RETURN_WITH_REPLY (c, IRC_ERR_NEEDMOREPARAMS, msg->command);
struct str result;
str_init (&result);
const char *nick;
if (str_map_find (&c->ctx->users, (nick = msg->params.vector[0])))
str_append (&result, nick);
for (size_t i = 1; i < msg->params.len; i++)
if (str_map_find (&c->ctx->users, (nick = msg->params.vector[i])))
str_append_printf (&result, " %s", nick);
irc_send_reply (c, IRC_RPL_ISON, result.str);
str_free (&result);
}
static void
irc_handle_kill (const struct irc_message *msg, struct client *c)
{
if (msg->params.len < 2)
RETURN_WITH_REPLY (c, IRC_ERR_NEEDMOREPARAMS, msg->command);
if (!(c->mode & IRC_USER_MODE_OPERATOR))
RETURN_WITH_REPLY (c, IRC_ERR_NOPRIVILEGES);
struct client *target;
if (!(target = str_map_find (&c->ctx->users, msg->params.vector[0])))
RETURN_WITH_REPLY (c, IRC_ERR_NOSUCHNICK, msg->params.vector[0]);
char *reason = xstrdup_printf ("Killed by %s: %s",
c->nickname, msg->params.vector[1]);
irc_close_link (target, reason);
free (reason);
}
static void
irc_handle_die (const struct irc_message *msg, struct client *c)
{
(void) msg;
if (!(c->mode & IRC_USER_MODE_OPERATOR))
RETURN_WITH_REPLY (c, IRC_ERR_NOPRIVILEGES);
if (!c->ctx->quitting)
irc_initiate_quit (c->ctx);
}
// -----------------------------------------------------------------------------
struct irc_command
{
const char *name;
bool requires_registration;
void (*handler) (const struct irc_message *, struct client *);
};
static void
irc_register_handlers (struct server_context *ctx)
{
// TODO: add an index for IRC_ERR_NOSUCHSERVER validation?
// TODO: add a minimal parameter count?
// TODO: add a field for oper-only commands?
static const struct irc_command message_handlers[] =
{
{ "PASS", false, irc_handle_pass },
{ "NICK", false, irc_handle_nick },
{ "USER", false, irc_handle_user },
{ "USERHOST", true, irc_handle_userhost },
{ "LUSERS", true, irc_handle_lusers },
{ "MOTD", true, irc_handle_motd },
{ "PING", true, irc_handle_ping },
{ "PONG", false, irc_handle_pong },
{ "QUIT", false, irc_handle_quit },
{ "TIME", true, irc_handle_time },
{ "VERSION", true, irc_handle_version },
{ "USERS", true, irc_handle_users },
{ "SUMMON", true, irc_handle_summon },
{ "AWAY", true, irc_handle_away },
{ "MODE", true, irc_handle_mode },
{ "PRIVMSG", true, irc_handle_privmsg },
{ "NOTICE", true, irc_handle_notice },
{ "JOIN", true, irc_handle_join },
{ "PART", true, irc_handle_part },
{ "KICK", true, irc_handle_kick },
{ "TOPIC", true, irc_handle_topic },
{ "LIST", true, irc_handle_list },
{ "NAMES", true, irc_handle_names },
{ "WHO", true, irc_handle_who },
{ "WHOIS", true, irc_handle_whois },
{ "ISON", true, irc_handle_ison },
{ "KILL", true, irc_handle_kill },
{ "DIE", true, irc_handle_die },
};
for (size_t i = 0; i < N_ELEMENTS (message_handlers); i++)
{
const struct irc_command *cmd = &message_handlers[i];
str_map_set (&ctx->handlers, cmd->name, (void *) cmd);
}
}
static void
irc_process_message (const struct irc_message *msg,
const char *raw, void *user_data)
{
(void) raw;
struct client *c = user_data;
if (c->closing_link)
return;
struct irc_command *cmd = str_map_find (&c->ctx->handlers, msg->command);
if (!cmd)
irc_send_reply (c, IRC_ERR_UNKNOWNCOMMAND, msg->command);
else if (cmd->requires_registration && !c->registered)
irc_send_reply (c, IRC_ERR_NOTREGISTERED);
else
cmd->handler (msg, c);
}
// --- Network I/O -------------------------------------------------------------
static bool
irc_try_read (struct client *c)
{
struct str *buf = &c->read_buffer;
ssize_t n_read;
while (true)
{
str_ensure_space (buf, 512);
n_read = recv (c->socket_fd, buf->str + buf->len,
buf->alloc - buf->len - 1 /* null byte */, 0);
if (n_read > 0)
{
buf->str[buf->len += n_read] = '\0';
// TODO: discard characters above the 512 character limit
irc_process_buffer (buf, irc_process_message, c);
continue;
}
if (n_read == 0)
{
client_kill (c, NULL);
return false;
}
if (errno == EAGAIN)
return true;
if (errno == EINTR)
continue;
print_debug ("%s: %s: %s", __func__, "recv", strerror (errno));
client_kill (c, strerror (errno));
return false;
}
}
static bool
irc_try_read_ssl (struct client *c)
{
if (c->ssl_tx_want_rx)
return true;
struct str *buf = &c->read_buffer;
c->ssl_rx_want_tx = false;
while (true)
{
str_ensure_space (buf, 512);
int n_read = SSL_read (c->ssl, buf->str + buf->len,
buf->alloc - buf->len - 1 /* null byte */);
const char *error_info = NULL;
switch (xssl_get_error (c->ssl, n_read, &error_info))
{
case SSL_ERROR_NONE:
buf->str[buf->len += n_read] = '\0';
// TODO: discard characters above the 512 character limit
irc_process_buffer (buf, irc_process_message, c);
continue;
case SSL_ERROR_ZERO_RETURN:
client_kill (c, NULL);
return false;
case SSL_ERROR_WANT_READ:
return true;
case SSL_ERROR_WANT_WRITE:
c->ssl_rx_want_tx = true;
return true;
case XSSL_ERROR_TRY_AGAIN:
continue;
default:
print_debug ("%s: %s: %s", __func__, "SSL_read", error_info);
client_kill (c, error_info);
return false;
}
}
}
static bool
irc_try_write (struct client *c)
{
struct str *buf = &c->write_buffer;
ssize_t n_written;
while (buf->len)
{
n_written = send (c->socket_fd, buf->str, buf->len, 0);
if (n_written >= 0)
{
str_remove_slice (buf, 0, n_written);
continue;
}
if (errno == EAGAIN)
return true;
if (errno == EINTR)
continue;
print_debug ("%s: %s: %s", __func__, "send", strerror (errno));
client_kill (c, strerror (errno));
return false;
}
return true;
}
static bool
irc_try_write_ssl (struct client *c)
{
if (c->ssl_rx_want_tx)
return true;
struct str *buf = &c->write_buffer;
c->ssl_tx_want_rx = false;
while (buf->len)
{
int n_written = SSL_write (c->ssl, buf->str, buf->len);
const char *error_info = NULL;
switch (xssl_get_error (c->ssl, n_written, &error_info))
{
case SSL_ERROR_NONE:
str_remove_slice (buf, 0, n_written);
continue;
case SSL_ERROR_ZERO_RETURN:
client_kill (c, NULL);
return false;
case SSL_ERROR_WANT_WRITE:
return true;
case SSL_ERROR_WANT_READ:
c->ssl_tx_want_rx = true;
return true;
case XSSL_ERROR_TRY_AGAIN:
continue;
default:
print_debug ("%s: %s: %s", __func__, "SSL_write", error_info);
client_kill (c, error_info);
return false;
}
}
return true;
}
static bool
irc_autodetect_ssl (struct client *c)
{
// Trivial SSL/TLS autodetection. The first block of data returned by
// recv() must be at least three bytes long for this to work reliably,
// but that should not pose a problem in practice.
//
// SSL2: 1xxx xxxx | xxxx xxxx | <1>
// (message length) (client hello)
// SSL3/TLS: <22> | <3> | xxxx xxxx
// (handshake)| (protocol version)
//
// Such byte sequences should never occur at the beginning of regular IRC
// communication, which usually begins with USER/NICK/PASS/SERVICE.
char buf[3];
start:
switch (recv (c->socket_fd, buf, sizeof buf, MSG_PEEK))
{
case 3:
if ((buf[0] & 0x80) && buf[2] == 1)
return true;
case 2:
if (buf[0] == 22 && buf[1] == 3)
return true;
break;
case 1:
if (buf[0] == 22)
return true;
break;
case 0:
break;
default:
if (errno == EINTR)
goto start;
}
return false;
}
static bool
client_initialize_ssl (struct client *c)
{
// SSL support not enabled
if (!c->ctx->ssl_ctx)
return false;
c->ssl = SSL_new (c->ctx->ssl_ctx);
if (!c->ssl)
goto error_ssl_1;
if (!SSL_set_fd (c->ssl, c->socket_fd))
goto error_ssl_2;
SSL_set_accept_state (c->ssl);
return true;
error_ssl_2:
SSL_free (c->ssl);
c->ssl = NULL;
error_ssl_1:
// XXX: these error strings are really nasty; also there could be
// multiple errors on the OpenSSL stack.
print_debug ("%s: %s: %s", "could not initialize SSL",
c->hostname, ERR_error_string (ERR_get_error (), NULL));
return false;
}
static void
on_irc_client_ready (const struct pollfd *pfd, void *user_data)
{
struct client *c = user_data;
if (!c->initialized)
{
hard_assert (pfd->events == POLLIN);
if (irc_autodetect_ssl (c) && !client_initialize_ssl (c))
{
client_kill (c, NULL);
return;
}
c->initialized = true;
client_set_ping_timer (c);
}
if (c->ssl)
{
// Reads may want to write, writes may want to read, poll() may
// return unexpected things in `revents'... let's try both
if (!irc_try_read_ssl (c) || !irc_try_write_ssl (c))
return;
}
else if (!irc_try_read (c) || !irc_try_write (c))
return;
client_update_poller (c, pfd);
// The purpose of the `closing_link' state is to transfer the `ERROR'
if (c->closing_link && !c->write_buffer.len)
client_kill (c, NULL);
}
static void
client_update_poller (struct client *c, const struct pollfd *pfd)
{
int new_events = POLLIN;
if (c->ssl)
{
if (c->write_buffer.len || c->ssl_rx_want_tx)
new_events |= POLLOUT;
// While we're waiting for an opposite event, we ignore the original
if (c->ssl_rx_want_tx) new_events &= ~POLLIN;
if (c->ssl_tx_want_rx) new_events &= ~POLLOUT;
}
else if (c->write_buffer.len)
new_events |= POLLOUT;
hard_assert (new_events != 0);
if (!pfd || pfd->events != new_events)
poller_set (&c->ctx->poller, c->socket_fd, new_events,
(poller_dispatcher_func) on_irc_client_ready, c);
}
static void
on_irc_client_available (const struct pollfd *pfd, void *user_data)
{
(void) pfd;
struct server_context *ctx = user_data;
while (true)
{
// XXX: `struct sockaddr_storage' is not the most portable thing
struct sockaddr_storage peer;
socklen_t peer_len = sizeof peer;
int fd = accept (ctx->listen_fd, (struct sockaddr *) &peer, &peer_len);
if (fd == -1)
{
if (errno == EAGAIN)
break;
if (errno == EINTR
|| errno == ECONNABORTED)
continue;
// TODO: handle resource exhaustion (EMFILE, ENFILE) specially
// (stop accepting new connections and wait until we close some).
// FIXME: handle this better, bring the server down cleanly.
exit_fatal ("%s: %s", "accept", strerror (errno));
}
if (ctx->max_connections != 0 && ctx->n_clients >= ctx->max_connections)
{
print_debug ("connection limit reached, refusing connection");
close (fd);
continue;
}
char host[NI_MAXHOST] = "unknown", port[NI_MAXSERV] = "unknown";
int err = getnameinfo ((struct sockaddr *) &peer, peer_len,
host, sizeof host, port, sizeof port, NI_NUMERICSERV);
if (err)
print_debug ("%s: %s", "getnameinfo", gai_strerror (err));
print_debug ("accepted connection from %s:%s", host, port);
struct client *c = xmalloc (sizeof *c);
client_init (c);
c->ctx = ctx;
c->socket_fd = fd;
c->hostname = xstrdup (host);
c->last_active = time (NULL);
LIST_PREPEND (ctx->clients, c);
ctx->n_clients++;
set_blocking (fd, false);
client_update_poller (c, NULL);
client_set_kill_timer (c);
}
}
// -----------------------------------------------------------------------------
static int
irc_ssl_verify_callback (int verify_ok, X509_STORE_CTX *ctx)
{
(void) verify_ok;
(void) ctx;
// We only want to provide additional privileges based on the client's
// certificate, so let's not terminate the connection because of a failure.
return 1;
}
static bool
irc_initialize_ssl (struct server_context *ctx, struct error **e)
{
const char *ssl_cert = str_map_find (&ctx->config, "ssl_cert");
const char *ssl_key = str_map_find (&ctx->config, "ssl_key");
// Only try to enable SSL support if the user configures it; it is not
// a failure if no one has requested it.
if (!ssl_cert && !ssl_key)
return true;
if (!ssl_cert)
error_set (e, "no SSL certificate set");
else if (!ssl_key)
error_set (e, "no SSL private key set");
if (!ssl_cert || !ssl_key)
return false;
char *cert_path = resolve_config_filename (ssl_cert);
char *key_path = resolve_config_filename (ssl_key);
if (!cert_path)
error_set (e, "%s: %s", "cannot open file", ssl_cert);
else if (!key_path)
error_set (e, "%s: %s", "cannot open file", ssl_key);
if (!cert_path || !key_path)
return false;
ctx->ssl_ctx = SSL_CTX_new (SSLv23_server_method ());
if (!ctx->ssl_ctx)
{
// XXX: these error strings are really nasty; also there could be
// multiple errors on the OpenSSL stack.
error_set (e, "%s: %s", "could not initialize SSL",
ERR_error_string (ERR_get_error (), NULL));
goto error_ssl_1;
}
SSL_CTX_set_verify (ctx->ssl_ctx,
SSL_VERIFY_PEER | SSL_VERIFY_CLIENT_ONCE, irc_ssl_verify_callback);
// XXX: maybe we should call SSL_CTX_set_options() for some workarounds
const unsigned char session_id_context[SSL_MAX_SSL_SESSION_ID_LENGTH]
= PROGRAM_NAME;
(void) SSL_CTX_set_session_id_context (ctx->ssl_ctx,
session_id_context, sizeof session_id_context);
// XXX: perhaps we should read the files ourselves for better messages
if (!SSL_CTX_use_certificate_chain_file (ctx->ssl_ctx, cert_path))
{
error_set (e, "%s: %s", "setting the SSL client certificate failed",
ERR_error_string (ERR_get_error (), NULL));
goto error_ssl_2;
}
if (!SSL_CTX_use_PrivateKey_file (ctx->ssl_ctx, key_path, SSL_FILETYPE_PEM))
{
error_set (e, "%s: %s", "setting the SSL private key failed",
ERR_error_string (ERR_get_error (), NULL));
goto error_ssl_2;
}
// TODO: SSL_CTX_check_private_key()? It has probably already been checked
// by SSL_CTX_use_PrivateKey_file() above.
// Gah, spare me your awkward semantics, I just want to push data!
// XXX: do we want SSL_MODE_AUTO_RETRY as well? I guess not.
SSL_CTX_set_mode (ctx->ssl_ctx,
SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER | SSL_MODE_ENABLE_PARTIAL_WRITE);
return true;
error_ssl_2:
SSL_CTX_free (ctx->ssl_ctx);
ctx->ssl_ctx = NULL;
error_ssl_1:
return false;
}
static bool
irc_initialize_catalog (struct server_context *ctx, struct error **e)
{
hard_assert (ctx->catalog == (nl_catd) -1);
const char *catalog = str_map_find (&ctx->config, "catalog");
if (!catalog)
return true;
char *path = resolve_config_filename (catalog);
if (!path)
{
error_set (e, "%s: %s", "cannot open file", catalog);
return false;
}
ctx->catalog = catopen (path, NL_CAT_LOCALE);
free (path);
if (ctx->catalog == (nl_catd) -1)
{
error_set (e, "%s: %s",
"failed reading the message catalog file", strerror (errno));
return false;
}
return true;
}
static bool
irc_initialize_motd (struct server_context *ctx, struct error **e)
{
hard_assert (ctx->motd.len == 0);
const char *motd = str_map_find (&ctx->config, "motd");
if (!motd)
return true;
char *path = resolve_config_filename (motd);
if (!path)
{
error_set (e, "%s: %s", "cannot open file", motd);
return false;
}
FILE *fp = fopen (path, "r");
free (path);
if (!fp)
{
error_set (e, "%s: %s",
"failed reading the MOTD file", strerror (errno));
return false;
}
struct str line;
str_init (&line);
while (read_line (fp, &line))
str_vector_add_owned (&ctx->motd, str_steal (&line));
str_free (&line);
fclose (fp);
return true;
}
/// This function handles values that require validation before their first use,
/// or some kind of a transformation (such as conversion to an integer) needs
/// to be done before they can be used directly.
static bool
irc_parse_config (struct server_context *ctx, struct error **e)
{
unsigned long ul;
#define PARSE_UNSIGNED(name, min, max) \
const char *name = str_map_find (&ctx->config, #name); \
hard_assert (name != NULL); \
if (!xstrtoul (&ul, name, 10) || ul > max || ul < min) \
{ \
error_set (e, "invalid configuration value for `%s': %s", \
#name, "the number is invalid or out of range"); \
return false; \
} \
ctx->name = ul
PARSE_UNSIGNED (ping_interval, 1, UINT_MAX);
PARSE_UNSIGNED (max_connections, 0, UINT_MAX);
return true;
}
static bool
irc_initialize_server_name (struct server_context *ctx, struct error **e)
{
enum validation_result res;
const char *server_name = str_map_find (&ctx->config, "server_name");
if (server_name)
{
res = irc_validate_hostname (server_name);
if (res != VALIDATION_OK)
{
error_set (e, "invalid configuration value for `%s': %s",
"server_name", irc_validate_to_str (res));
return false;
}
ctx->server_name = xstrdup (server_name);
}
else
{
char hostname[HOST_NAME_MAX];
if (gethostname (hostname, sizeof hostname))
{
error_set (e, "%s: %s",
"getting the hostname failed", strerror (errno));
return false;
}
res = irc_validate_hostname (hostname);
if (res != VALIDATION_OK)
{
error_set (e,
"`%s' is not set and the hostname (`%s') cannot be used: %s",
"server_name", hostname, irc_validate_to_str (res));
return false;
}
ctx->server_name = xstrdup (hostname);
}
return true;
}
static bool
irc_listen (struct server_context *ctx, struct error **e)
{
const char *bind_host = str_map_find (&ctx->config, "bind_host");
const char *bind_port = str_map_find (&ctx->config, "bind_port");
hard_assert (bind_port != NULL); // We have a default value for this
struct addrinfo gai_hints, *gai_result, *gai_iter;
memset (&gai_hints, 0, sizeof gai_hints);
gai_hints.ai_socktype = SOCK_STREAM;
gai_hints.ai_flags = AI_PASSIVE;
int err = getaddrinfo (bind_host, bind_port, &gai_hints, &gai_result);
if (err)
{
error_set (e, "%s: %s: %s",
"network setup failed", "getaddrinfo", gai_strerror (err));
return false;
}
int sockfd;
char real_host[NI_MAXHOST], real_port[NI_MAXSERV];
for (gai_iter = gai_result; gai_iter; gai_iter = gai_iter->ai_next)
{
sockfd = socket (gai_iter->ai_family,
gai_iter->ai_socktype, gai_iter->ai_protocol);
if (sockfd == -1)
continue;
set_cloexec (sockfd);
int yes = 1;
soft_assert (setsockopt (sockfd, SOL_SOCKET, SO_KEEPALIVE,
&yes, sizeof yes) != -1);
soft_assert (setsockopt (sockfd, SOL_SOCKET, SO_REUSEADDR,
&yes, sizeof yes) != -1);
real_host[0] = real_port[0] = '\0';
err = getnameinfo (gai_iter->ai_addr, gai_iter->ai_addrlen,
real_host, sizeof real_host, real_port, sizeof real_port,
NI_NUMERICHOST | NI_NUMERICSERV);
if (err)
print_debug ("%s: %s", "getnameinfo", gai_strerror (err));
if (bind (sockfd, gai_iter->ai_addr, gai_iter->ai_addrlen))
print_error ("bind to %s:%s failed: %s",
real_host, real_port, strerror (errno));
else if (listen (sockfd, 16 /* arbitrary number */))
print_error ("listen at %s:%s failed: %s",
real_host, real_port, strerror (errno));
else
break;
xclose (sockfd);
}
freeaddrinfo (gai_result);
if (!gai_iter)
{
error_set (e, "network setup failed");
return false;
}
set_blocking (sockfd, false);
ctx->listen_fd = sockfd;
poller_set (&ctx->poller, ctx->listen_fd, POLLIN,
(poller_dispatcher_func) on_irc_client_available, ctx);
print_status ("listening at %s:%s", real_host, real_port);
return true;
}
static void
on_signal_pipe_readable (const struct pollfd *fd, struct server_context *ctx)
{
char *dummy;
(void) read (fd->fd, &dummy, 1);
if (g_termination_requested && !ctx->quitting)
irc_initiate_quit (ctx);
}
static void
daemonize (void)
{
// TODO: create and lock a PID file?
print_status ("daemonizing...");
if (chdir ("/"))
exit_fatal ("%s: %s", "chdir", strerror (errno));
pid_t pid;
if ((pid = fork ()) < 0)
exit_fatal ("%s: %s", "fork", strerror (errno));
else if (pid)
exit (EXIT_SUCCESS);
setsid ();
signal (SIGHUP, SIG_IGN);
if ((pid = fork ()) < 0)
exit_fatal ("%s: %s", "fork", strerror (errno));
else if (pid)
exit (EXIT_SUCCESS);
openlog (PROGRAM_NAME, LOG_NDELAY | LOG_NOWAIT | LOG_PID, 0);
g_log_message_real = log_message_syslog;
// XXX: we may close our own descriptors this way, crippling ourselves
for (int i = 0; i < 3; i++)
xclose (i);
int tty = open ("/dev/null", O_RDWR);
if (tty != 0 || dup (0) != 1 || dup (0) != 2)
exit_fatal ("failed to reopen FD's: %s", strerror (errno));
}
static void
print_usage (const char *program_name)
{
fprintf (stderr,
"Usage: %s [OPTION]...\n"
"Experimental IRC server.\n"
"\n"
" -d, --debug run in debug mode (do not daemonize)\n"
" -h, --help display this help and exit\n"
" -V, --version output version information and exit\n"
" --write-default-cfg [filename]\n"
" write a default configuration file and exit\n",
program_name);
}
int
main (int argc, char *argv[])
{
const char *invocation_name = argv[0];
static struct option opts[] =
{
{ "debug", no_argument, NULL, 'd' },
{ "help", no_argument, NULL, 'h' },
{ "version", no_argument, NULL, 'V' },
{ "write-default-cfg", optional_argument, NULL, 'w' },
{ NULL, 0, NULL, 0 }
};
while (1)
{
int c, opt_index;
c = getopt_long (argc, argv, "dhV", opts, &opt_index);
if (c == -1)
break;
switch (c)
{
case 'd':
g_debug_mode = true;
break;
case 'h':
print_usage (invocation_name);
exit (EXIT_SUCCESS);
case 'V':
printf (PROGRAM_NAME " " PROGRAM_VERSION "\n");
exit (EXIT_SUCCESS);
case 'w':
call_write_default_config (optarg, g_config_table);
exit (EXIT_SUCCESS);
default:
print_error ("wrong options");
exit (EXIT_FAILURE);
}
}
print_status (PROGRAM_NAME " " PROGRAM_VERSION " starting");
setup_signal_handlers ();
SSL_library_init ();
atexit (EVP_cleanup);
SSL_load_error_strings ();
// XXX: ERR_load_BIO_strings()? Anything else?
atexit (ERR_free_strings);
struct server_context ctx;
server_context_init (&ctx);
irc_register_handlers (&ctx);
struct error *e = NULL;
if (!read_config_file (&ctx.config, &e))
{
print_error ("error loading configuration: %s", e->message);
error_free (e);
exit (EXIT_FAILURE);
}
poller_set (&ctx.poller, g_signal_pipe[0], POLLIN,
(poller_dispatcher_func) on_signal_pipe_readable, &ctx);
if (!irc_initialize_ssl (&ctx, &e)
|| !irc_initialize_server_name (&ctx, &e)
|| !irc_initialize_motd (&ctx, &e)
|| !irc_initialize_catalog (&ctx, &e)
|| !irc_parse_config (&ctx, &e)
|| !irc_listen (&ctx, &e))
{
print_error ("%s", e->message);
error_free (e);
exit (EXIT_FAILURE);
}
if (!g_debug_mode)
daemonize ();
ctx.polling = true;
while (ctx.polling)
poller_run (&ctx.poller);
server_context_free (&ctx);
return EXIT_SUCCESS;
}