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| author | Přemysl Janouch <p.janouch@gmail.com> | 2014-08-10 00:01:38 +0200 |
|---|---|---|
| committer | Přemysl Janouch <p.janouch@gmail.com> | 2014-08-10 00:01:38 +0200 |
| commit | bd68e28b608fb74bb4823726b9f0bf6489ad94b5 (patch) | |
| tree | ff082bd52d8dfde8cc8d2f223e2d9b3c63bcc770 /kike.c | |
| parent | 0da22a799a215f00ebc2be9e7cf5cc505db27148 (diff) | |
| download | xK-bd68e28b608fb74bb4823726b9f0bf6489ad94b5.tar.gz xK-bd68e28b608fb74bb4823726b9f0bf6489ad94b5.tar.xz xK-bd68e28b608fb74bb4823726b9f0bf6489ad94b5.zip | |
Remove the `src' directory
There are not that many files, and aren't going to be.
Diffstat (limited to 'kike.c')
| -rw-r--r-- | kike.c | 3251 |
1 files changed, 3251 insertions, 0 deletions
@@ -0,0 +1,3251 @@ +/* + * 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)" }, + + { "operators", NULL, "IRCop SSL cert. fingerprints" }, + + { "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}$", key); +} + +#undef SN +#undef N4 +#undef N6 + +#undef LE +#undef SP + +static bool +irc_is_valid_user_mask (const char *mask) +{ + return irc_regex_match ("^[^!@]+![^!@]+@[^@!]+$", mask); +} + +static bool +irc_is_valid_fingerprint (const char *fp) +{ + return irc_regex_match ("^[a-fA-F0-9]{2}(:[a-fA-F0-9]{2}){19}$", fp); +} + +// --- Clients (equals users) -------------------------------------------------- + +#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 *ssl_cert_fingerprint; ///< Client certificate fingerprint + + 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_close_link (struct client *, const char *); +static void client_send (struct client *, const char *, ...) + ATTRIBUTE_PRINTF (2, 3); +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 *); + +// --- Channels ---------------------------------------------------------------- + +#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; + struct client *c; +}; + +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 struct channel * +channel_new (void) +{ + struct channel *self = xcalloc (1, 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); + return self; +} + +static void +channel_delete (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); + + free (self); +} + +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'); + + // XXX: is it correct to split it? Try it on an existing implementation. + if (disclose_secrets) + { + if (self->user_limit != -1) + str_append_printf (&mode, " %ld", self->user_limit); + if (self->key) + str_append_printf (&mode, " %s", self->key); + } + return str_steal (&mode); +} + +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 (iter->c == c) + return iter; + return NULL; +} + +static struct channel_user * +channel_add_user (struct channel *chan, struct client *c) +{ + struct channel_user *link = xcalloc (1, sizeof *link); + link->c = c; + 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; +} + +// --- IRC server context ------------------------------------------------------ + +struct server_context +{ + int listen_fds[1]; ///< Listening socket FD's + size_t n_listen_fds; ///< Number of listening sockets + + 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 + struct str_map operators; ///< SSL cert. fingerprints for IRCops +}; + +static void +server_context_init (struct server_context *self) +{ + self->n_listen_fds = 0; + self->clients = NULL; + self->n_clients = 0; + + str_map_init (&self->users); + self->users.key_xfrm = irc_strxfrm; + str_map_init (&self->channels); + self->channels.key_xfrm = irc_strxfrm; + self->channels.free = (void (*) (void *)) channel_delete; + 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; + str_map_init (&self->operators); + // The regular irc_strxfrm() is sufficient for fingerprints + self->operators.key_xfrm = irc_strxfrm; +} + +static void +server_context_free (struct server_context *self) +{ + str_map_free (&self->config); + + for (size_t i = 0; i < self->n_listen_fds; i++) + xclose (self->listen_fds[i]); + 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); + str_map_free (&self->operators); +} + +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 void +irc_try_finish_quit (struct server_context *ctx) +{ + if (!ctx->n_clients && ctx->quitting) + ctx->polling = false; +} + +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) + client_close_link (iter, "Shutting down"); + + for (size_t i = 0; i < ctx->n_listen_fds; i++) + { + ssize_t index = poller_find_by_fd (&ctx->poller, ctx->listen_fds[i]); + if (soft_assert (index != -1)) + poller_remove_at_index (&ctx->poller, index); + xclose (ctx->listen_fds[i]); + } + ctx->n_listen_fds = 0; + + ctx->quitting = true; + irc_try_finish_quit (ctx); +} + +static struct channel * +irc_channel_create (struct server_context *ctx, const char *name) +{ + struct channel *chan = channel_new (); + chan->ctx = ctx; + chan->name = xstrdup (name); + str_map_set (&ctx->channels, name, chan); + return chan; +} + +static void +irc_channel_destroy_if_empty (struct server_context *ctx, struct channel *chan) +{ + if (!chan->users) + str_map_set (&ctx->channels, chan->name, NULL); +} + +static void +irc_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->c->nickname, + str_map_find (&c->ctx->users, iter->c->nickname)); + } + + str_map_iter_init (&iter, &targets); + struct client *target; + while ((target = str_map_iter_next (&iter))) + client_send (target, "%s", message); +} + +// --- Clients (continued) ----------------------------------------------------- + +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); +} + +static void +client_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 +client_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); + + client_send_str (c, &tmp); + str_free (&tmp); +} + +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); + irc_send_to_roommates (c, message); + free (message); + + struct str_map_iter iter; + str_map_iter_init (&iter, &c->ctx->channels); + struct channel *chan, *next = str_map_iter_next (&iter); + for (chan = next; chan; chan = next) + { + next = str_map_iter_next (&iter); + struct channel_user *user; + if (!(user = channel_get_user (chan, c))) + continue; + channel_remove_user (chan, user); + irc_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 +client_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. + client_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 (mask->vector[i], client)) + { + result = true; + break; + } + free (client); + return result; +} + +static char * +client_get_ssl_cert_fingerprint (struct client *c) +{ + if (!c->ssl) + return NULL; + + X509 *peer_cert = SSL_get_peer_certificate (c->ssl); + if (!peer_cert) + return NULL; + + int cert_len = i2d_X509 (peer_cert, NULL); + if (cert_len < 0) + return NULL; + + unsigned char cert[cert_len], *p = cert; + if (i2d_X509 (peer_cert, &p) < 0) + return NULL; + + unsigned char hash[SHA_DIGEST_LENGTH]; + SHA1 (cert, cert_len, hash); + + struct str fingerprint; + str_init (&fingerprint); + str_append_printf (&fingerprint, "%02X", hash[0]); + for (size_t i = 1; i < sizeof hash; i++) + str_append_printf (&fingerprint, ":%02X", hash[i]); + return str_steal (&fingerprint); +} + +// --- 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_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_client_kill_timer, c->ctx->ping_interval); +} + +static void +on_client_timeout_timer (void *user_data) +{ + struct client *c = user_data; + char *reason = xstrdup_printf + ("Ping timeout: >%u seconds", c->ctx->ping_interval); + client_close_link (c, reason); + free (reason); +} + +static void +on_client_ping_timer (void *user_data) +{ + struct client *c = user_data; + hard_assert (!c->closing_link); + client_send (c, "PING :%s", c->ctx->server_name); + client_set_timer (c, on_client_timeout_timer, c->ctx->ping_interval); +} + +static void +client_set_ping_timer (struct client *c) +{ + client_set_timer (c, on_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_NOADMININFO = 423, + 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_KEYSET = 467, + IRC_ERR_CHANNELISFULL = 471, + IRC_ERR_UNKNOWNMODE = 472, + 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_NOADMININFO] = "%s :No administrative info available", + [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_KEYSET] = "%s :Channel key already set", + [IRC_ERR_CHANNELISFULL] = "%s :Cannot join channel (+l)", + [IRC_ERR_UNKNOWNMODE] = "%c :is unknown mode char to me for %s", + [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); + + client_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) + client_send (c, ":%s MODE %s :+%s", c->nickname, c->nickname, mode); + free (mode); + + hard_assert (c->ssl_cert_fingerprint == NULL); + if ((c->ssl_cert_fingerprint = client_get_ssl_cert_fingerprint (c))) + client_send (c, ":%s NOTICE %s :" + "Your SSL client certificate fingerprint is %s", + ctx->server_name, c->nickname, c->ssl_cert_fingerprint); +} + +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); + irc_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 + client_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); + client_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) + { + if (iter->c != except) + client_send (iter->c, "%s", message); + } +} + +static bool +irc_modify_mode (unsigned *mask, unsigned mode, bool add) +{ + unsigned orig = *mask; + if (add) + *mask |= mode; + else + *mask &= ~mode; + return *mask != orig; +} + +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) + client_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': + // It's not possible to un-restrict yourself + if (adding) + new_mode |= IRC_USER_MODE_RESTRICTED; + break; + case 'o': + if (!adding) + new_mode &= ~IRC_USER_MODE_OPERATOR; + else if (c->ssl_cert_fingerprint + && str_map_find (&c->ctx->operators, c->ssl_cert_fingerprint)) + new_mode |= IRC_USER_MODE_OPERATOR; + else + client_send (c, ":%s NOTICE %s :Either you're not using an SSL" + " client certificate, or the fingerprint doesn't match", + c->ctx->server_name, c->nickname); + 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_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 char * +irc_check_expand_user_mask (const char *mask) +{ + struct str result; + str_init (&result); + str_append (&result, mask); + + // Make sure it is a complete mask + if (!strchr (result.str, '!')) + str_append (&result, "!*"); + if (!strchr (result.str, '@')) + str_append (&result, "@*"); + + // And validate whatever the result is + if (!irc_is_valid_user_mask (result.str)) + { + str_free (&result); + return NULL; + } + return str_steal (&result); +} + +static void +irc_handle_chan_mode_change (struct client *c, + struct channel *chan, char *params[]) +{ + struct channel_user *user = channel_get_user (chan, c); + + // This is by far the worst command to implement from the whole RFC; + // don't blame me if it doesn't work exactly as expected. + + struct str added; struct str_vector added_params; + struct str removed; struct str_vector removed_params; + + str_init (&added); str_vector_init (&added_params); + str_init (&removed); str_vector_init (&removed_params); + +// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - + + // TODO: try to convert this madness into functions; that will most + // likely require creating a special parser class +#define NEEDS_OPER \ + if (!user || (!(user->modes & IRC_CHAN_MODE_OPERATOR) \ + && !(c->mode & IRC_USER_MODE_OPERATOR))) \ + { \ + irc_send_reply (c, IRC_ERR_CHANOPRIVSNEEDED, chan->name); \ + continue; \ + } + +#define HANDLE_USER(mode) \ + if (!(target = *params)) \ + continue; \ + params++; \ + NEEDS_OPER \ + if (!(client = str_map_find (&c->ctx->users, target))) \ + irc_send_reply (c, IRC_ERR_NOSUCHNICK, target); \ + else if (!(target_user = channel_get_user (chan, client))) \ + irc_send_reply (c, IRC_ERR_USERNOTINCHANNEL, \ + target, chan->name); \ + else if (irc_modify_mode (&target_user->modes, (mode), adding)) \ + { \ + str_append_c (output, mode_char); \ + str_vector_add (output_params, client->nickname); \ + } + +#define HANDLE_LIST(list, list_msg, end_msg) \ +{ \ + if (!(target = *params)) \ + { \ + if (adding) \ + irc_send_channel_list (c, chan->name, list, list_msg, end_msg); \ + continue; \ + } \ + params++; \ + NEEDS_OPER \ + char *mask = irc_check_expand_user_mask (target); \ + if (!mask) \ + continue; \ + size_t i; \ + for (i = 0; i < (list)->len; i++) \ + if (!irc_strcmp ((list)->vector[i], mask)) \ + break; \ + if (!((i != (list)->len) ^ adding)) \ + { \ + free (mask); \ + continue; \ + } \ + if (adding) \ + str_vector_add ((list), mask); \ + else \ + str_vector_remove ((list), i); \ + str_append_c (output, mode_char); \ + str_vector_add (output_params, mask); \ + free (mask); \ +} + +#define HANDLE_MODE(mode) \ + NEEDS_OPER \ + if (irc_modify_mode (&chan->modes, (mode), adding)) \ + str_append_c (output, mode_char); + +#define REMOVE_MODE(removed_mode, removed_char) \ + if (adding && irc_modify_mode (&chan->modes, (removed_mode), false)) \ + str_append_c (&removed, (removed_char)); + +// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - + + const char *mode_string; + while ((mode_string = *params++)) + { + bool adding = true; + struct str *output = &added; + struct str_vector *output_params = &added_params; + + const char *target; + struct channel_user *target_user; + struct client *client; + + char mode_char; + while (*mode_string) + switch ((mode_char = *mode_string++)) + { + case '+': + adding = true; + output = &added; + output_params = &added_params; + break; + case '-': + adding = false; + output = &removed; + output_params = &removed_params; + break; + + case 'o': HANDLE_USER (IRC_CHAN_MODE_OPERATOR) break; + case 'v': HANDLE_USER (IRC_CHAN_MODE_VOICE) break; + + case 'i': HANDLE_MODE (IRC_CHAN_MODE_INVITE_ONLY) break; + case 'm': HANDLE_MODE (IRC_CHAN_MODE_MODERATED) break; + case 'n': HANDLE_MODE (IRC_CHAN_MODE_NO_OUTSIDE_MSGS) break; + case 'q': HANDLE_MODE (IRC_CHAN_MODE_QUIET) break; + case 't': HANDLE_MODE (IRC_CHAN_MODE_PROTECTED_TOPIC) break; + + case 'p': + HANDLE_MODE (IRC_CHAN_MODE_PRIVATE) + REMOVE_MODE (IRC_CHAN_MODE_SECRET, 's') + break; + case 's': + HANDLE_MODE (IRC_CHAN_MODE_SECRET) + REMOVE_MODE (IRC_CHAN_MODE_PRIVATE, 'p') + break; + + case 'b': + HANDLE_LIST (&chan->ban_list, + IRC_RPL_BANLIST, IRC_RPL_ENDOFBANLIST) + break; + case 'e': + HANDLE_LIST (&chan->exception_list, + IRC_RPL_EXCEPTLIST, IRC_RPL_ENDOFEXCEPTLIST) + break; + case 'I': + HANDLE_LIST (&chan->invite_list, + IRC_RPL_INVITELIST, IRC_RPL_ENDOFINVITELIST) + break; + + case 'k': + NEEDS_OPER + if (!adding) + { + if (!(target = *params)) + continue; + params++; + if (!chan->key || irc_strcmp (target, chan->key)) + continue; + + str_append_c (&removed, mode_char); + str_vector_add (&removed_params, chan->key); + free (chan->key); + chan->key = NULL; + } + else if (!(target = *params)) + continue; + else + { + params++; + if (chan->key) + irc_send_reply (c, IRC_ERR_KEYSET, chan->name); + else + { + chan->key = xstrdup (target); + str_append_c (&added, mode_char); + str_vector_add (&added_params, chan->key); + } + } + break; + case 'l': + NEEDS_OPER + if (!adding) + { + if (chan->user_limit == -1) + continue; + + chan->user_limit = -1; + str_append_c (&removed, mode_char); + } + else if (!(target = *params)) + continue; + else + { + params++; + unsigned long x; + if (xstrtoul (&x, target, 10) && x > 0 && x <= LONG_MAX) + { + chan->user_limit = x; + str_append_c (&added, mode_char); + str_vector_add (&added_params, target); + } + } + break; + + default: + RETURN_WITH_REPLY (c, IRC_ERR_UNKNOWNMODE); + } + } + +#undef NEEDS_OPER +#undef HANDLE_USER +#undef HANDLE_LIST +#undef HANDLE_MODE +#undef REMOVE_MODE + + if (added.len || removed.len) + { + struct str message; + str_init (&message); + str_append_printf (&message, ":%s!%s@%s MODE %s ", + c->nickname, c->username, c->hostname, chan->name); + if (added.len) + str_append_printf (&message, "+%s", added.str); + if (removed.len) + str_append_printf (&message, "-%s", removed.str); + for (size_t i = 0; i < added_params.len; i++) + str_append_printf (&message, " %s", added_params.vector[i]); + for (size_t i = 0; i < removed_params.len; i++) + str_append_printf (&message, " %s", removed_params.vector[i]); + irc_channel_multicast (chan, message.str, NULL); + str_free (&message); + } + + str_free (&added); str_vector_free (&added_params); + str_free (&removed); str_vector_free (&removed_params); +} + +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); + } + else + irc_handle_chan_mode_change (c, chan, &msg->params.vector[1]); + 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) + { + client_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) + { + if (!on_channel && (iter->c->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, iter->c->nickname); + str_vector_add_owned (&nicks, str_steal (&result)); + } + + if (nicks.len) + { + // FIXME: split it into multiple messages if it's too long + 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) + { + if ((on_chan || !(iter->c->mode & IRC_USER_MODE_INVISIBLE)) + && (!only_ops || (iter->c->mode & IRC_USER_MODE_OPERATOR))) + irc_send_rpl_whoreply (c, chan, iter->c); + } + } + 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 + client_send (c, "%s", message); + free (message); + + channel_remove_user (chan, user); + irc_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 + client_send (c, "%s", message); + free (message); + + channel_remove_user (chan, user); + irc_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 = irc_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 + client_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_admin (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]); + irc_send_reply (c, IRC_ERR_NOADMININFO, c->ctx->server_name); +} + +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]); + client_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 }, + { "ADMIN", true, irc_handle_admin }, + + { "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_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_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 (pfd->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); + } +} + +// --- Application setup ------------------------------------------------------- + +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); + + bool result = true; + struct str_vector fingerprints; + str_vector_init (&fingerprints); + const char *operators = str_map_find (&ctx->config, "operators"); + if (operators) + split_str_ignore_empty (operators, ',', &fingerprints); + for (size_t i = 0; i < fingerprints.len; i++) + { + const char *key = fingerprints.vector[i]; + if (!irc_is_valid_fingerprint (key)) + { + error_set (e, "invalid configuration value for `%s': %s", + "operators", "invalid fingerprint value"); + result = false; + break; + } + str_map_set (&ctx->operators, key, (void *) 1); + } + str_vector_free (&fingerprints); + return result; +} + +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 int +irc_listen (struct addrinfo *gai_iter) +{ + int fd = socket (gai_iter->ai_family, + gai_iter->ai_socktype, gai_iter->ai_protocol); + if (fd == -1) + return -1; + set_cloexec (fd); + + int yes = 1; + soft_assert (setsockopt (fd, SOL_SOCKET, SO_KEEPALIVE, + &yes, sizeof yes) != -1); + soft_assert (setsockopt (fd, SOL_SOCKET, SO_REUSEADDR, + &yes, sizeof yes) != -1); + + char real_host[NI_MAXHOST], real_port[NI_MAXSERV]; + real_host[0] = real_port[0] = '\0'; + int 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 (fd, 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 (fd, 16 /* arbitrary number */)) + print_error ("listen at %s:%s failed: %s", + real_host, real_port, strerror (errno)); + else + { + print_status ("listening at %s:%s", real_host, real_port); + return fd; + } + + xclose (fd); + return -1; +} + +static bool +irc_setup_listen_fds (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 fd; + for (gai_iter = gai_result; gai_iter; gai_iter = gai_iter->ai_next) + { + if (ctx->n_listen_fds >= N_ELEMENTS (ctx->listen_fds)) + break; + if ((fd = irc_listen (gai_iter)) == -1) + continue; + + ctx->listen_fds[ctx->n_listen_fds++] = fd; + set_blocking (fd, false); + poller_set (&ctx->poller, fd, POLLIN, + (poller_dispatcher_func) on_irc_client_available, ctx); + break; + } + freeaddrinfo (gai_result); + + if (!ctx->n_listen_fds) + { + error_set (e, "network setup failed"); + return false; + } + return true; +} + +// --- Main -------------------------------------------------------------------- + +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_setup_listen_fds (&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; +} |