diff options
Diffstat (limited to 'zyklonb.c')
| -rw-r--r-- | zyklonb.c | 2063 |
1 files changed, 0 insertions, 2063 deletions
diff --git a/zyklonb.c b/zyklonb.c deleted file mode 100644 index 08ffb1b..0000000 --- a/zyklonb.c +++ /dev/null @@ -1,2063 +0,0 @@ -/* - * zyklonb.c: a modular IRC bot - * - * Copyright (c) 2014 - 2020, Přemysl Eric Janouch <p@janouch.name> - * - * Permission to use, copy, modify, and/or distribute this software for any - * purpose with or without fee is hereby granted. - * - * 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. - * - */ - -#include "config.h" -#define PROGRAM_NAME "ZyklonB" - -#include "common.c" - -// --- Configuration (application-specific) ------------------------------------ - -static struct simple_config_item g_config_table[] = -{ - { "nickname", "ZyklonB", "IRC nickname" }, - { "username", "bot", "IRC user name" }, - { "realname", "ZyklonB IRC bot", "IRC real name/e-mail" }, - - { "irc_host", NULL, "Address of the IRC server" }, - { "irc_port", "6667", "Port of the IRC server" }, - { "tls", "off", "Whether to use TLS" }, - { "tls_cert", NULL, "Client TLS certificate (PEM)" }, - { "tls_verify", "on", "Whether to verify certificates" }, - { "tls_ca_file", NULL, "OpenSSL CA bundle file" }, - { "tls_ca_path", NULL, "OpenSSL CA bundle path" }, - { "autojoin", NULL, "Channels to join on start" }, - { "reconnect", "on", "Whether to reconnect on error" }, - { "reconnect_delay", "5", "Time between reconnecting" }, - - { "socks_host", NULL, "Address of a SOCKS 4a/5 proxy" }, - { "socks_port", "1080", "SOCKS port number" }, - { "socks_username", NULL, "SOCKS auth. username" }, - { "socks_password", NULL, "SOCKS auth. password" }, - - { "prefix", ":", "The prefix for bot commands" }, - { "admin", NULL, "Host mask for administrators" }, - { "plugins", NULL, "The plugins to load on startup" }, - { "plugin_dir", NULL, "Plugin search path override" }, - { "recover", "on", "Whether to re-launch on crash" }, - - { NULL, NULL, NULL } -}; - -// --- Application data -------------------------------------------------------- - -struct plugin -{ - LIST_HEADER (struct plugin) - struct bot_context *ctx; ///< Parent context - - char *name; ///< Plugin identifier - pid_t pid; ///< PID of the plugin process - - bool is_zombie; ///< Whether the child is a zombie - bool initialized; ///< Ready to exchange IRC messages - struct str queued_output; ///< Output queued up until initialized - - // Since we're doing non-blocking I/O, we need to queue up data so that - // we don't stall on plugins unnecessarily. - - int read_fd; ///< The read end of the comm. pipe - int write_fd; ///< The write end of the comm. pipe - - struct poller_fd read_event; ///< Read FD event - struct poller_fd write_event; ///< Write FD event - - struct str read_buffer; ///< Unprocessed input - struct str write_buffer; ///< Output yet to be sent out -}; - -static struct plugin * -plugin_new (void) -{ - struct plugin *self = xcalloc (1, sizeof *self); - self->pid = -1; - self->queued_output = str_make (); - - self->read_fd = -1; - self->read_buffer = str_make (); - self->write_fd = -1; - self->write_buffer = str_make (); - return self; -} - -static void -plugin_destroy (struct plugin *self) -{ - soft_assert (self->pid == -1); - free (self->name); - - str_free (&self->read_buffer); - if (!soft_assert (self->read_fd == -1)) - xclose (self->read_fd); - - str_free (&self->write_buffer); - if (!soft_assert (self->write_fd == -1)) - xclose (self->write_fd); - - if (!self->initialized) - str_free (&self->queued_output); - - free (self); -} - -// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -struct bot_context -{ - struct str_map config; ///< User configuration - regex_t *admin_re; ///< Regex to match our administrator - bool reconnect; ///< Whether to reconnect on conn. fail. - unsigned long reconnect_delay; ///< Reconnect delay in seconds - - int irc_fd; ///< Socket FD of the server - struct str read_buffer; ///< Input yet to be processed - struct poller_fd irc_event; ///< IRC FD event - bool irc_registered; ///< Whether we may send messages now - - struct poller_fd signal_event; ///< Signal FD event - struct poller_timer ping_tmr; ///< We should send a ping - struct poller_timer timeout_tmr; ///< Connection seems to be dead - struct poller_timer reconnect_tmr; ///< We should reconnect now - - SSL_CTX *ssl_ctx; ///< SSL context - SSL *ssl; ///< SSL connection - - struct plugin *plugins; ///< Linked list of plugins - struct str_map plugins_by_name; ///< Indexes @em plugins by their name - - struct poller poller; ///< Manages polled descriptors - bool quitting; ///< User requested quitting - bool polling; ///< The event loop is running -}; - -static void on_irc_ping_timeout (void *user_data); -static void on_irc_timeout (void *user_data); -static void on_irc_reconnect_timeout (void *user_data); - -static void -bot_context_init (struct bot_context *self) -{ - self->config = str_map_make (free); - simple_config_load_defaults (&self->config, g_config_table); - self->admin_re = NULL; - - self->irc_fd = -1; - self->read_buffer = str_make (); - self->irc_registered = false; - - self->ssl = NULL; - self->ssl_ctx = NULL; - - self->plugins = NULL; - self->plugins_by_name = str_map_make (NULL); - - poller_init (&self->poller); - self->quitting = false; - self->polling = false; - - self->timeout_tmr = poller_timer_make (&self->poller); - self->timeout_tmr.dispatcher = on_irc_timeout; - self->timeout_tmr.user_data = self; - - self->ping_tmr = poller_timer_make (&self->poller); - self->ping_tmr.dispatcher = on_irc_ping_timeout; - self->ping_tmr.user_data = self; - - self->reconnect_tmr = poller_timer_make (&self->poller); - self->reconnect_tmr.dispatcher = on_irc_reconnect_timeout; - self->reconnect_tmr.user_data = self; -} - -static void -bot_context_free (struct bot_context *self) -{ - str_map_free (&self->config); - if (self->admin_re) - regex_free (self->admin_re); - str_free (&self->read_buffer); - - // TODO: terminate the plugins properly before this is called - LIST_FOR_EACH (struct plugin, link, self->plugins) - plugin_destroy (link); - - if (self->irc_fd != -1) - { - poller_fd_reset (&self->irc_event); - xclose (self->irc_fd); - } - if (self->ssl) - SSL_free (self->ssl); - if (self->ssl_ctx) - SSL_CTX_free (self->ssl_ctx); - - str_map_free (&self->plugins_by_name); - poller_free (&self->poller); -} - -static void -irc_shutdown (struct bot_context *ctx) -{ - // TODO: set a timer after which we cut the connection? - // Generally non-critical - if (ctx->ssl) - soft_assert (SSL_shutdown (ctx->ssl) != -1); - else - soft_assert (shutdown (ctx->irc_fd, SHUT_WR) == 0); -} - -static void -try_finish_quit (struct bot_context *ctx) -{ - if (ctx->quitting && ctx->irc_fd == -1 && !ctx->plugins) - ctx->polling = false; -} - -static bool plugin_zombify (struct plugin *); - -static void -initiate_quit (struct bot_context *ctx) -{ - // Initiate bringing down of the two things that block our shutdown: - // a/ the IRC socket, b/ our child processes: - - for (struct plugin *plugin = ctx->plugins; - plugin; plugin = plugin->next) - plugin_zombify (plugin); - if (ctx->irc_fd != -1) - irc_shutdown (ctx); - - ctx->quitting = true; - try_finish_quit (ctx); -} - -static bool irc_send (struct bot_context *ctx, - const char *format, ...) ATTRIBUTE_PRINTF (2, 3); - -static bool -irc_send (struct bot_context *ctx, const char *format, ...) -{ - va_list ap; - - if (g_debug_mode) - { - fputs ("[IRC] <== \"", stderr); - va_start (ap, format); - vfprintf (stderr, format, ap); - va_end (ap); - fputs ("\"\n", stderr); - } - - if (!soft_assert (ctx->irc_fd != -1)) - return false; - - va_start (ap, format); - struct str str = str_make (); - str_append_vprintf (&str, format, ap); - str_append (&str, "\r\n"); - va_end (ap); - - bool result = true; - if (ctx->ssl) - { - // TODO: call SSL_get_error() to detect if a clean shutdown has occured - ERR_clear_error (); - if (SSL_write (ctx->ssl, str.str, str.len) != (int) str.len) - { - print_debug ("%s: %s: %s", __func__, "SSL_write", - xerr_describe_error ()); - result = false; - } - } - else if (write (ctx->irc_fd, str.str, str.len) != (ssize_t) str.len) - { - print_debug ("%s: %s: %s", __func__, "write", strerror (errno)); - result = false; - } - - str_free (&str); - return result; -} - -static bool -irc_get_boolean_from_config - (struct bot_context *ctx, const char *name, bool *value, struct error **e) -{ - const char *str = str_map_find (&ctx->config, name); - hard_assert (str != NULL); - - if (set_boolean_if_valid (value, str)) - return true; - - return error_set (e, "invalid configuration value for `%s'", name); -} - -static bool -irc_initialize_ca_set (SSL_CTX *ssl_ctx, const char *file, const char *path, - struct error **e) -{ - ERR_clear_error (); - - if (file || path) - { - if (SSL_CTX_load_verify_locations (ssl_ctx, file, path)) - return true; - - return error_set (e, "%s: %s", - "failed to set locations for the CA certificate bundle", - xerr_describe_error ()); - } - - if (!SSL_CTX_set_default_verify_paths (ssl_ctx)) - return error_set (e, "%s: %s", - "couldn't load the default CA certificate bundle", - xerr_describe_error ()); - return true; -} - -static bool -irc_initialize_ca (struct bot_context *ctx, struct error **e) -{ - const char *ca_file = str_map_find (&ctx->config, "tls_ca_file"); - const char *ca_path = str_map_find (&ctx->config, "tls_ca_path"); - - char *full_file = ca_file - ? resolve_filename (ca_file, resolve_relative_config_filename) : NULL; - char *full_path = ca_path - ? resolve_filename (ca_path, resolve_relative_config_filename) : NULL; - - bool ok = false; - if (ca_file && !full_file) - error_set (e, "couldn't find the CA bundle file"); - else if (ca_path && !full_path) - error_set (e, "couldn't find the CA bundle path"); - else - ok = irc_initialize_ca_set (ctx->ssl_ctx, full_file, full_path, e); - - free (full_file); - free (full_path); - return ok; -} - -static bool -irc_initialize_ssl_ctx (struct bot_context *ctx, struct error **e) -{ - // Disable deprecated protocols (see RFC 7568) - SSL_CTX_set_options (ctx->ssl_ctx, SSL_OP_NO_SSLv2 | SSL_OP_NO_SSLv3); - - bool verify; - if (!irc_get_boolean_from_config (ctx, "tls_verify", &verify, e)) - return false; - SSL_CTX_set_verify (ctx->ssl_ctx, - verify ? SSL_VERIFY_PEER : SSL_VERIFY_NONE, NULL); - - struct error *error = NULL; - if (!irc_initialize_ca (ctx, &error)) - { - if (verify) - { - error_propagate (e, error); - return false; - } - - // Only inform the user if we're not actually verifying - print_warning ("%s", error->message); - error_free (error); - } - return true; -} - -static bool -irc_initialize_tls (struct bot_context *ctx, struct error **e) -{ - const char *error_info = NULL; - ctx->ssl_ctx = SSL_CTX_new (SSLv23_client_method ()); - if (!ctx->ssl_ctx) - goto error_ssl_1; - if (!irc_initialize_ssl_ctx (ctx, e)) - goto error_ssl_2; - - ctx->ssl = SSL_new (ctx->ssl_ctx); - if (!ctx->ssl) - goto error_ssl_2; - - const char *tls_cert = str_map_find (&ctx->config, "tls_cert"); - if (tls_cert) - { - char *path = resolve_filename - (tls_cert, resolve_relative_config_filename); - if (!path) - print_error ("%s: %s", "cannot open file", tls_cert); - // XXX: perhaps we should read the file ourselves for better messages - else if (!SSL_use_certificate_file (ctx->ssl, path, SSL_FILETYPE_PEM) - || !SSL_use_PrivateKey_file (ctx->ssl, path, SSL_FILETYPE_PEM)) - print_error ("%s: %s", "setting the TLS client certificate failed", - xerr_describe_error ()); - free (path); - } - - SSL_set_connect_state (ctx->ssl); - if (!SSL_set_fd (ctx->ssl, ctx->irc_fd)) - goto error_ssl_3; - // Avoid SSL_write() returning SSL_ERROR_WANT_READ - SSL_set_mode (ctx->ssl, SSL_MODE_AUTO_RETRY); - - switch (xssl_get_error (ctx->ssl, SSL_connect (ctx->ssl), &error_info)) - { - case SSL_ERROR_NONE: - return true; - case SSL_ERROR_ZERO_RETURN: - error_info = "server closed the connection"; - default: - break; - } - -error_ssl_3: - SSL_free (ctx->ssl); - ctx->ssl = NULL; -error_ssl_2: - SSL_CTX_free (ctx->ssl_ctx); - ctx->ssl_ctx = NULL; -error_ssl_1: - if (!error_info) - error_info = xerr_describe_error (); - return error_set (e, "%s: %s", "could not initialize TLS", error_info); -} - -static bool -irc_establish_connection (struct bot_context *ctx, - const char *host, const char *port, struct error **e) -{ - struct addrinfo gai_hints, *gai_result, *gai_iter; - memset (&gai_hints, 0, sizeof gai_hints); - gai_hints.ai_socktype = SOCK_STREAM; - - int err = getaddrinfo (host, port, &gai_hints, &gai_result); - if (err) - return error_set (e, "%s: %s: %s", "connection failed", - "getaddrinfo", gai_strerror (err)); - - int sockfd; - 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); - - const char *real_host = host; - - // Let's try to resolve the address back into a real hostname; - // we don't really need this, so we can let it quietly fail - char buf[NI_MAXHOST]; - err = getnameinfo (gai_iter->ai_addr, gai_iter->ai_addrlen, - buf, sizeof buf, NULL, 0, 0); - if (err) - print_debug ("%s: %s", "getnameinfo", gai_strerror (err)); - else - real_host = buf; - - // XXX: we shouldn't mix these statuses with `struct error'; choose 1! - char *address = format_host_port_pair (real_host, port); - print_status ("connecting to %s...", address); - free (address); - - if (!connect (sockfd, gai_iter->ai_addr, gai_iter->ai_addrlen)) - break; - - xclose (sockfd); - } - - freeaddrinfo (gai_result); - - if (!gai_iter) - return error_set (e, "connection failed"); - - ctx->irc_fd = sockfd; - return true; -} - -// --- Signals ----------------------------------------------------------------- - -static int g_signal_pipe[2]; ///< A pipe used to signal... signals - -static struct strv - g_original_argv, ///< Original program arguments - g_recovery_env; ///< Environment for re-exec recovery - -/// Program termination has been requested by a signal -static volatile sig_atomic_t g_termination_requested; - -/// Points to startup reason location within `g_recovery_environment' -static char **g_startup_reason_location; -/// The environment variable used to pass the startup reason when re-executing -static const char g_startup_reason_str[] = "STARTUP_REASON"; - -static void -sigchld_handler (int signum) -{ - (void) signum; - - int original_errno = errno; - // Just so that the read end of the pipe wakes up the poller. - // NOTE: Linux has signalfd() and eventfd(), and the BSD's have kqueue. - // All of them are better than this approach, although platform-specific. - if (write (g_signal_pipe[1], "c", 1) == -1) - soft_assert (errno == EAGAIN); - errno = original_errno; -} - -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); - - struct sigaction sa; - sa.sa_flags = SA_RESTART; - sa.sa_handler = sigchld_handler; - sigemptyset (&sa.sa_mask); - - if (sigaction (SIGCHLD, &sa, NULL) == -1) - exit_fatal ("sigaction: %s", strerror (errno)); - - signal (SIGPIPE, SIG_IGN); - - sa.sa_handler = sigterm_handler; - if (sigaction (SIGINT, &sa, NULL) == -1 - || sigaction (SIGTERM, &sa, NULL) == -1) - exit_fatal ("sigaction: %s", strerror (errno)); -} - -static void -translate_signal_info (int no, const char **name, int code, const char **reason) -{ - if (code == SI_USER) *reason = "signal sent by kill()"; - if (code == SI_QUEUE) *reason = "signal sent by sigqueue()"; - - switch (no) - { - case SIGILL: - *name = "SIGILL"; - if (code == ILL_ILLOPC) *reason = "illegal opcode"; - if (code == ILL_ILLOPN) *reason = "illegal operand"; - if (code == ILL_ILLADR) *reason = "illegal addressing mode"; - if (code == ILL_ILLTRP) *reason = "illegal trap"; - if (code == ILL_PRVOPC) *reason = "privileged opcode"; - if (code == ILL_PRVREG) *reason = "privileged register"; - if (code == ILL_COPROC) *reason = "coprocessor error"; - if (code == ILL_BADSTK) *reason = "internal stack error"; - break; - case SIGFPE: - *name = "SIGFPE"; - if (code == FPE_INTDIV) *reason = "integer divide by zero"; - if (code == FPE_INTOVF) *reason = "integer overflow"; - if (code == FPE_FLTDIV) *reason = "floating-point divide by zero"; - if (code == FPE_FLTOVF) *reason = "floating-point overflow"; - if (code == FPE_FLTUND) *reason = "floating-point underflow"; - if (code == FPE_FLTRES) *reason = "floating-point inexact result"; - if (code == FPE_FLTINV) *reason = "invalid floating-point operation"; - if (code == FPE_FLTSUB) *reason = "subscript out of range"; - break; - case SIGSEGV: - *name = "SIGSEGV"; - if (code == SEGV_MAPERR) - *reason = "address not mapped to object"; - if (code == SEGV_ACCERR) - *reason = "invalid permissions for mapped object"; - break; - case SIGBUS: - *name = "SIGBUS"; - if (code == BUS_ADRALN) *reason = "invalid address alignment"; - if (code == BUS_ADRERR) *reason = "nonexistent physical address"; - if (code == BUS_OBJERR) *reason = "object-specific hardware error"; - break; - default: - *name = NULL; - } -} - -static void -recovery_handler (int signum, siginfo_t *info, void *context) -{ - (void) context; - - // TODO: maybe try to force a core dump like this: if (fork() == 0) return; - // TODO: maybe we could even send "\r\nQUIT :reason\r\n" to the server. >_> - // As long as we're not connected via TLS, that is. - - const char *signal_name = NULL, *reason = NULL; - translate_signal_info (signum, &signal_name, info->si_code, &reason); - - char buf[128], numbuf[8]; - if (!signal_name) - { - snprintf (numbuf, sizeof numbuf, "%d", signum); - signal_name = numbuf; - } - - if (reason) - snprintf (buf, sizeof buf, "%s=%s: %s: %s", g_startup_reason_str, - "signal received", signal_name, reason); - else - snprintf (buf, sizeof buf, "%s=%s: %s", g_startup_reason_str, - "signal received", signal_name); - *g_startup_reason_location = buf; - - // Avoid annoying resource intensive infinite loops by sleeping for a bit - (void) sleep (1); - - // TODO: maybe pregenerate the path, see the following for some other ways - // that would be illegal to do from within a signal handler: - // http://stackoverflow.com/a/1024937 - // http://stackoverflow.com/q/799679 - // Especially if we change the current working directory in the program. - // - // Note that I can just overwrite g_orig_argv[0]. - - // NOTE: our children will read EOF on the read ends of their pipes as a - // a result of O_CLOEXEC. That should be enough to make them terminate. - - char **argv = g_original_argv.vector, **argp = g_recovery_env.vector; - execve ("/proc/self/exe", argv, argp); // Linux - execve ("/proc/curproc/file", argv, argp); // BSD - execve ("/proc/curproc/exe", argv, argp); // BSD - execve ("/proc/self/path/a.out", argv, argp); // Solaris - execve (argv[0], argv, argp); // unreliable fallback - - // Let's just crash - perror ("execve"); - signal (signum, SIG_DFL); - raise (signum); -} - -static void -prepare_recovery_environment (void) -{ - g_recovery_env = strv_make (); - strv_append_vector (&g_recovery_env, environ); - - // Prepare a location within the environment where we will put the startup - // (or maybe rather restart) reason in case of an irrecoverable error. - char **iter; - for (iter = g_recovery_env.vector; *iter; iter++) - { - const size_t len = sizeof g_startup_reason_str - 1; - if (!strncmp (*iter, g_startup_reason_str, len) && (*iter)[len] == '=') - break; - } - - if (*iter) - g_startup_reason_location = iter; - else - { - g_startup_reason_location = g_recovery_env.vector + g_recovery_env.len; - strv_append (&g_recovery_env, ""); - } -} - -static bool -setup_recovery_handler (struct bot_context *ctx, struct error **e) -{ - bool recover; - if (!irc_get_boolean_from_config (ctx, "recover", &recover, e)) - return false; - if (!recover) - return true; - - // Make sure these signals aren't blocked, otherwise we would be unable - // to handle them, making the critical conditions fatal. - sigset_t mask; - sigemptyset (&mask); - sigaddset (&mask, SIGSEGV); - sigaddset (&mask, SIGBUS); - sigaddset (&mask, SIGFPE); - sigaddset (&mask, SIGILL); - sigprocmask (SIG_UNBLOCK, &mask, NULL); - - struct sigaction sa; - sa.sa_flags = SA_SIGINFO; - sa.sa_sigaction = recovery_handler; - sigemptyset (&sa.sa_mask); - - prepare_recovery_environment (); - - // TODO: also handle SIGABRT... or avoid doing abort() in the first place? - if (sigaction (SIGSEGV, &sa, NULL) == -1 - || sigaction (SIGBUS, &sa, NULL) == -1 - || sigaction (SIGFPE, &sa, NULL) == -1 - || sigaction (SIGILL, &sa, NULL) == -1) - print_error ("sigaction: %s", strerror (errno)); - return true; -} - -// --- Plugins ----------------------------------------------------------------- - -/// The name of the special IRC command for interprocess communication -static const char *plugin_ipc_command = "ZYKLONB"; - -static struct plugin * -plugin_find_by_pid (struct bot_context *ctx, pid_t pid) -{ - struct plugin *iter; - for (iter = ctx->plugins; iter; iter = iter->next) - if (iter->pid == pid) - return iter; - return NULL; -} - -static bool -plugin_zombify (struct plugin *plugin) -{ - if (plugin->is_zombie) - return false; - - // FIXME: make sure that we don't remove entries from the poller while we - // still may have stuff to read; maybe just check that the read pipe is - // empty before closing it... and then on EOF check if `pid == -1' and - // only then dispose of it (it'd be best to simulate that both of these - // cases may happen). - poller_fd_reset (&plugin->write_event); - - // TODO: try to flush the write buffer (non-blocking)? - - // The plugin should terminate itself after it receives EOF. - xclose (plugin->write_fd); - plugin->write_fd = -1; - - // Make it a pseudo-anonymous zombie. In this state we process any - // remaining commands it attempts to send to us before it finally dies. - str_map_set (&plugin->ctx->plugins_by_name, plugin->name, NULL); - plugin->is_zombie = true; - - // TODO: wait a few seconds and then send SIGKILL to the plugin - return true; -} - -static void -on_plugin_writable (const struct pollfd *fd, struct plugin *plugin) -{ - struct str *buf = &plugin->write_buffer; - size_t written_total = 0; - - if (fd->revents & ~(POLLOUT | POLLHUP | POLLERR)) - print_debug ("fd %d: unexpected revents: %d", fd->fd, fd->revents); - - while (written_total != buf->len) - { - ssize_t n_written = write (fd->fd, buf->str + written_total, - buf->len - written_total); - - if (n_written < 0) - { - if (errno == EAGAIN) - break; - if (errno == EINTR) - continue; - - soft_assert (errno == EPIPE); - // Zombies shouldn't get dispatched for writability - hard_assert (!plugin->is_zombie); - - print_debug ("%s: %s", "write", strerror (errno)); - print_error ("failure on writing to plugin `%s'," - " therefore I'm unloading it", plugin->name); - plugin_zombify (plugin); - break; - } - - // This may be equivalent to EAGAIN on some implementations - if (n_written == 0) - break; - - written_total += n_written; - } - - if (written_total != 0) - str_remove_slice (buf, 0, written_total); - - if (buf->len == 0) - // Everything has been written, there's no need to end up in here again - poller_fd_reset (&plugin->write_event); -} - -static void -plugin_queue_write (struct plugin *plugin) -{ - if (plugin->is_zombie) - return; - - // Don't let the write buffer grow indefinitely. If there's a ton of data - // waiting to be processed by the plugin, it usually means there's something - // wrong with it (such as someone stopping the process). - if (plugin->write_buffer.len >= (1 << 20)) - { - print_warning ("plugin `%s' does not seem to process messages fast" - " enough, I'm unloading it", plugin->name); - plugin_zombify (plugin); - return; - } - poller_fd_set (&plugin->write_event, POLLOUT); -} - -static void -plugin_send (struct plugin *plugin, const char *format, ...) - ATTRIBUTE_PRINTF (2, 3); - -static void -plugin_send (struct plugin *plugin, const char *format, ...) -{ - va_list ap; - - if (g_debug_mode) - { - fprintf (stderr, "[%s] <-- \"", plugin->name); - va_start (ap, format); - vfprintf (stderr, format, ap); - va_end (ap); - fputs ("\"\n", stderr); - } - - va_start (ap, format); - str_append_vprintf (&plugin->write_buffer, format, ap); - va_end (ap); - str_append (&plugin->write_buffer, "\r\n"); - - plugin_queue_write (plugin); -} - -static void -plugin_process_ipc (struct plugin *plugin, const struct irc_message *msg) -{ - // Replies are sent in the order in which they came in, so there's - // no need to attach a special identifier to them. It might be - // desirable in some cases, though. - - if (msg->params.len < 1) - return; - - const char *command = msg->params.vector[0]; - if (!plugin->initialized && !strcasecmp (command, "register")) - { - // Register for relaying of IRC traffic - plugin->initialized = true; - - // Flush any queued up traffic here. The point of queuing it in - // the first place is so that we don't have to wait for plugin - // initialization during startup. - // - // Note that if we start filtering data coming to the plugins e.g. - // based on what it tells us upon registration, we might need to - // filter `queued_output' as well. - str_append_str (&plugin->write_buffer, &plugin->queued_output); - str_free (&plugin->queued_output); - - // NOTE: this may trigger the buffer length check - plugin_queue_write (plugin); - } - else if (!strcasecmp (command, "get_config")) - { - if (msg->params.len < 2) - return; - - const char *value = - str_map_find (&plugin->ctx->config, msg->params.vector[1]); - // TODO: escape the value (although there's no need to ATM) - plugin_send (plugin, "%s :%s", - plugin_ipc_command, value ? value : ""); - } - else if (!strcasecmp (command, "print")) - { - if (msg->params.len < 2) - return; - - printf ("%s\n", msg->params.vector[1]); - } -} - -static void -plugin_process_message (const struct irc_message *msg, - const char *raw, void *user_data) -{ - struct plugin *plugin = user_data; - struct bot_context *ctx = plugin->ctx; - - if (g_debug_mode) - fprintf (stderr, "[%s] --> \"%s\"\n", plugin->name, raw); - - if (!strcasecmp (msg->command, plugin_ipc_command)) - plugin_process_ipc (plugin, msg); - else if (plugin->initialized && ctx->irc_registered) - { - // Pass everything else through to the IRC server - // XXX: when the server isn't ready yet, these messages get silently - // discarded, which shouldn't pose a problem most of the time. - // Perhaps we could send a "connected" notification on `register' - // if `irc_ready' is true, or after it becomes true later, so that - // plugins know when to start sending unprovoked IRC messages. - // XXX: another case is when the connection gets interrupted and the - // plugin tries to send something back while we're reconnecting. - // For that we might set up a global buffer that gets flushed out - // after `irc_ready' becomes true. Note that there is always some - // chance of messages getting lost without us even noticing it. - irc_send (ctx, "%s", raw); - } -} - -static void -on_plugin_readable (const struct pollfd *fd, struct plugin *plugin) -{ - if (fd->revents & ~(POLLIN | POLLHUP | POLLERR)) - print_debug ("fd %d: unexpected revents: %d", fd->fd, fd->revents); - - // TODO: see if I can reuse irc_fill_read_buffer() - struct str *buf = &plugin->read_buffer; - while (true) - { - str_reserve (buf, 512 + 1); - ssize_t n_read = read (fd->fd, buf->str + buf->len, - buf->alloc - buf->len - 1); - - if (n_read < 0) - { - if (errno == EAGAIN) - break; - if (soft_assert (errno == EINTR)) - continue; - - if (!plugin->is_zombie) - { - print_error ("failure on reading from plugin `%s'," - " therefore I'm unloading it", plugin->name); - plugin_zombify (plugin); - } - return; - } - - // EOF; hopefully it will die soon (maybe it already has) - if (n_read == 0) - break; - - buf->str[buf->len += n_read] = '\0'; - if (buf->len >= (1 << 20)) - { - // XXX: this isn't really the best flood prevention mechanism, - // but it wasn't even supposed to be one. - if (plugin->is_zombie) - { - print_error ("a zombie of plugin `%s' is trying to flood us," - " therefore I'm killing it", plugin->name); - kill (plugin->pid, SIGKILL); - } - else - { - print_error ("plugin `%s' seems to spew out data frantically," - " therefore I'm unloading it", plugin->name); - plugin_zombify (plugin); - } - return; - } - } - - irc_process_buffer (buf, plugin_process_message, plugin); -} - -static bool -is_valid_plugin_name (const char *name) -{ - if (!*name) - return false; - for (const char *p = name; *p; p++) - if (!isgraph (*p) || *p == '/') - return false; - return true; -} - -static char * -plugin_resolve_relative_filename (const char *filename) -{ - struct strv paths = strv_make (); - get_xdg_data_dirs (&paths); - char *result = resolve_relative_filename_generic - (&paths, PROGRAM_NAME "/plugins/", filename); - strv_free (&paths); - return result; -} - -static struct plugin * -plugin_launch (struct bot_context *ctx, const char *name, struct error **e) -{ - char *path = NULL; - const char *plugin_dir = str_map_find (&ctx->config, "plugin_dir"); - if (plugin_dir) - { - // resolve_relative_filename_generic() won't accept relative paths, - // so just keep the old behaviour and expect the file to exist. - // We could use resolve_filename() on "plugin_dir" with paths=getcwd(). - path = xstrdup_printf ("%s/%s", plugin_dir, name); - } - else if (!(path = plugin_resolve_relative_filename (name))) - { - error_set (e, "plugin not found"); - goto fail_0; - } - - int stdin_pipe[2]; - if (pipe (stdin_pipe) == -1) - { - error_set (e, "%s: %s", "pipe", strerror (errno)); - goto fail_0; - } - - int stdout_pipe[2]; - if (pipe (stdout_pipe) == -1) - { - error_set (e, "%s: %s", "pipe", strerror (errno)); - goto fail_1; - } - - struct str work_dir = str_make (); - get_xdg_home_dir (&work_dir, "XDG_DATA_HOME", ".local/share"); - str_append_printf (&work_dir, "/%s", PROGRAM_NAME); - - if (!mkdir_with_parents (work_dir.str, e)) - goto fail_2; - - set_cloexec (stdin_pipe[1]); - set_cloexec (stdout_pipe[0]); - - pid_t pid = fork (); - if (pid == -1) - { - error_set (e, "%s: %s", "fork", strerror (errno)); - goto fail_2; - } - - if (pid == 0) - { - // Redirect the child's stdin and stdout to the pipes - if (dup2 (stdin_pipe[0], STDIN_FILENO) == -1 - || dup2 (stdout_pipe[1], STDOUT_FILENO) == -1) - { - print_error ("%s: %s: %s", "failed to load the plugin", - "dup2", strerror (errno)); - _exit (EXIT_FAILURE); - } - if (chdir (work_dir.str)) - { - print_error ("%s: %s: %s", "failed to load the plugin", - "chdir", strerror (errno)); - _exit (EXIT_FAILURE); - } - - xclose (stdin_pipe[0]); - xclose (stdout_pipe[1]); - - // Restore some of the signal handling - signal (SIGPIPE, SIG_DFL); - - char *argv[] = { path, NULL }; - execve (argv[0], argv, environ); - - // We will collect the failure later via SIGCHLD - print_error ("%s: %s: %s", "failed to load the plugin", - "exec", strerror (errno)); - _exit (EXIT_FAILURE); - } - - str_free (&work_dir); - free (path); - - xclose (stdin_pipe[0]); - xclose (stdout_pipe[1]); - - struct plugin *plugin = plugin_new (); - plugin->ctx = ctx; - plugin->pid = pid; - plugin->name = xstrdup (name); - plugin->read_fd = stdout_pipe[0]; - plugin->write_fd = stdin_pipe[1]; - return plugin; - -fail_2: - str_free (&work_dir); - xclose (stdout_pipe[0]); - xclose (stdout_pipe[1]); -fail_1: - xclose (stdin_pipe[0]); - xclose (stdin_pipe[1]); -fail_0: - free (path); - return NULL; -} - -static bool -plugin_load (struct bot_context *ctx, const char *name, struct error **e) -{ - if (!is_valid_plugin_name (name)) - return error_set (e, "invalid plugin name"); - if (str_map_find (&ctx->plugins_by_name, name)) - return error_set (e, "the plugin has already been loaded"); - - struct plugin *plugin; - if (!(plugin = plugin_launch (ctx, name, e))) - return false; - - set_blocking (plugin->read_fd, false); - set_blocking (plugin->write_fd, false); - - plugin->read_event = poller_fd_make (&ctx->poller, plugin->read_fd); - plugin->read_event.dispatcher = (poller_fd_fn) on_plugin_readable; - plugin->read_event.user_data = plugin; - - plugin->write_event = poller_fd_make (&ctx->poller, plugin->write_fd); - plugin->write_event.dispatcher = (poller_fd_fn) on_plugin_writable; - plugin->write_event.user_data = plugin; - - LIST_PREPEND (ctx->plugins, plugin); - str_map_set (&ctx->plugins_by_name, name, plugin); - - poller_fd_set (&plugin->read_event, POLLIN); - return true; -} - -static bool -plugin_unload (struct bot_context *ctx, const char *name, struct error **e) -{ - struct plugin *plugin = str_map_find (&ctx->plugins_by_name, name); - - if (!plugin) - return error_set (e, "no such plugin is loaded"); - - plugin_zombify (plugin); - - // TODO: add a `kill zombies' command to forcefully get rid of processes - // that do not understand the request. - return true; -} - -static void -plugin_load_all_from_config (struct bot_context *ctx) -{ - const char *plugin_list = str_map_find (&ctx->config, "plugins"); - if (!plugin_list) - return; - - struct strv plugins = strv_make (); - cstr_split (plugin_list, ",", true, &plugins); - for (size_t i = 0; i < plugins.len; i++) - { - char *name = cstr_strip_in_place (plugins.vector[i], " "); - - struct error *e = NULL; - if (!plugin_load (ctx, name, &e)) - { - print_error ("plugin `%s' failed to load: %s", name, e->message); - error_free (e); - } - } - - strv_free (&plugins); -} - -// --- Main program ------------------------------------------------------------ - -static bool -parse_bot_command (const char *s, const char *command, const char **following) -{ - size_t command_len = strlen (command); - if (strncasecmp (s, command, command_len)) - return false; - s += command_len; - - // Expect a word boundary, so that we don't respond to invalid things - if (isalnum (*s)) - return false; - - // Ignore any initial spaces; the rest is the command's argument - while (isblank (*s)) - s++; - *following = s; - return true; -} - -static void -split_bot_command_argument_list (const char *arguments, struct strv *out) -{ - cstr_split (arguments, ",", true, out); - for (size_t i = 0; i < out->len; ) - { - if (!*cstr_strip_in_place (out->vector[i], " \t")) - strv_remove (out, i); - else - i++; - } -} - -static bool -is_private_message (const struct irc_message *msg) -{ - hard_assert (msg->params.len); - return !strchr ("#&+!", *msg->params.vector[0]); -} - -static bool -is_sent_by_admin (struct bot_context *ctx, const struct irc_message *msg) -{ - // No administrator set -> everyone is an administrator - if (!ctx->admin_re) - return true; - return regexec (ctx->admin_re, msg->prefix, 0, NULL, 0) != REG_NOMATCH; -} - -static void respond_to_user (struct bot_context *ctx, const struct - irc_message *msg, const char *format, ...) ATTRIBUTE_PRINTF (3, 4); - -static void -respond_to_user (struct bot_context *ctx, const struct irc_message *msg, - const char *format, ...) -{ - if (!soft_assert (msg->prefix && msg->params.len)) - return; - - char nick[strcspn (msg->prefix, "!") + 1]; - strncpy (nick, msg->prefix, sizeof nick - 1); - nick[sizeof nick - 1] = '\0'; - - va_list ap; - struct str text = str_make (); - va_start (ap, format); - str_append_vprintf (&text, format, ap); - va_end (ap); - - if (is_private_message (msg)) - irc_send (ctx, "PRIVMSG %s :%s", nick, text.str); - else - irc_send (ctx, "PRIVMSG %s :%s: %s", - msg->params.vector[0], nick, text.str); - - str_free (&text); -} - -static void -process_plugin_load (struct bot_context *ctx, - const struct irc_message *msg, const char *name) -{ - struct error *e = NULL; - if (plugin_load (ctx, name, &e)) - respond_to_user (ctx, msg, "plugin `%s' queued for loading", name); - else - { - respond_to_user (ctx, msg, "plugin `%s' could not be loaded: %s", - name, e->message); - error_free (e); - } -} - -static void -process_plugin_unload (struct bot_context *ctx, - const struct irc_message *msg, const char *name) -{ - struct error *e = NULL; - if (plugin_unload (ctx, name, &e)) - respond_to_user (ctx, msg, "plugin `%s' unloaded", name); - else - { - respond_to_user (ctx, msg, "plugin `%s' could not be unloaded: %s", - name, e->message); - error_free (e); - } -} - -static void -process_plugin_reload (struct bot_context *ctx, - const struct irc_message *msg, const char *name) -{ - // XXX: we might want to wait until the plugin terminates before we try - // to reload it (so that it can save its configuration or whatever) - - // So far the only error that can occur is that the plugin hasn't been - // loaded, which in this case doesn't really matter. - plugin_unload (ctx, name, NULL); - - process_plugin_load (ctx, msg, name); -} - -static char * -make_status_report (struct bot_context *ctx) -{ - struct str report = str_make (); - const char *reason = getenv (g_startup_reason_str); - if (!reason) - reason = "launched normally"; - str_append_printf (&report, "\x02startup reason:\x0f %s", reason); - - size_t zombies = 0; - const char *prepend = "; \x02plugins:\x0f "; - for (struct plugin *plugin = ctx->plugins; plugin; plugin = plugin->next) - { - if (plugin->is_zombie) - zombies++; - else - { - str_append_printf (&report, "%s%s", prepend, plugin->name); - prepend = ", "; - } - } - if (!ctx->plugins) - str_append_printf (&report, "%s\x02none\x0f", prepend); - - str_append_printf (&report, "; \x02zombies:\x0f %zu", zombies); - return str_steal (&report); -} - -static void -process_privmsg (struct bot_context *ctx, const struct irc_message *msg) -{ - if (!is_sent_by_admin (ctx, msg)) - return; - if (msg->params.len < 2) - return; - - const char *prefix = str_map_find (&ctx->config, "prefix"); - hard_assert (prefix != NULL); // We have a default value for this - - // For us to recognize the command, it has to start with the prefix, - // with the exception of PM's sent directly to us. - const char *text = msg->params.vector[1]; - if (!strncmp (text, prefix, strlen (prefix))) - text += strlen (prefix); - else if (!is_private_message (msg)) - return; - - const char *following; - struct strv list = strv_make (); - - if (parse_bot_command (text, "quote", &following)) - // This seems to replace tons of random stupid commands - irc_send (ctx, "%s", following); - else if (parse_bot_command (text, "quit", &following)) - { - // We actually need this command (instead of just `quote') because we - // could try to reconnect to the server automatically otherwise. - if (*following) - irc_send (ctx, "QUIT :%s", following); - else - irc_send (ctx, "QUIT"); - initiate_quit (ctx); - } - else if (parse_bot_command (text, "status", &following)) - { - char *report = make_status_report (ctx); - respond_to_user (ctx, msg, "%s", report); - free (report); - } - else if (parse_bot_command (text, "load", &following)) - { - split_bot_command_argument_list (following, &list); - for (size_t i = 0; i < list.len; i++) - process_plugin_load (ctx, msg, list.vector[i]); - } - else if (parse_bot_command (text, "reload", &following)) - { - split_bot_command_argument_list (following, &list); - for (size_t i = 0; i < list.len; i++) - process_plugin_reload (ctx, msg, list.vector[i]); - } - else if (parse_bot_command (text, "unload", &following)) - { - split_bot_command_argument_list (following, &list); - for (size_t i = 0; i < list.len; i++) - process_plugin_unload (ctx, msg, list.vector[i]); - } - - strv_free (&list); -} - -static void -irc_forward_message_to_plugins (struct bot_context *ctx, const char *raw) -{ - // For consistency with plugin_process_message() - if (!ctx->irc_registered) - return; - - for (struct plugin *plugin = ctx->plugins; - plugin; plugin = plugin->next) - { - if (plugin->is_zombie) - continue; - - if (plugin->initialized) - plugin_send (plugin, "%s", raw); - else - // TODO: make sure that this buffer doesn't get too large either - str_append_printf (&plugin->queued_output, "%s\r\n", raw); - } -} - -static void -irc_process_message (const struct irc_message *msg, - const char *raw, void *user_data) -{ - struct bot_context *ctx = user_data; - if (g_debug_mode) - fprintf (stderr, "[%s] ==> \"%s\"\n", "IRC", raw); - - // This should be as minimal as possible, I don't want to have the whole bot - // written in C, especially when I have this overengineered plugin system. - // Therefore the very basic functionality only. - // - // I should probably even rip out the autojoin... - - irc_forward_message_to_plugins (ctx, raw); - - if (!strcasecmp (msg->command, "PING")) - { - if (msg->params.len) - irc_send (ctx, "PONG :%s", msg->params.vector[0]); - else - irc_send (ctx, "PONG"); - } - else if (!ctx->irc_registered && !strcasecmp (msg->command, "001")) - { - print_status ("successfully connected"); - ctx->irc_registered = true; - - const char *autojoin = str_map_find (&ctx->config, "autojoin"); - if (autojoin) - irc_send (ctx, "JOIN :%s", autojoin); - } - else if (!strcasecmp (msg->command, "PRIVMSG")) - process_privmsg (ctx, msg); -} - -enum irc_read_result -{ - IRC_READ_OK, ///< Some data were read successfully - IRC_READ_EOF, ///< The server has closed connection - IRC_READ_AGAIN, ///< No more data at the moment - IRC_READ_ERROR ///< General connection failure -}; - -static enum irc_read_result -irc_fill_read_buffer_tls (struct bot_context *ctx, struct str *buf) -{ - int n_read; -start: - ERR_clear_error (); - n_read = SSL_read (ctx->ssl, buf->str + buf->len, - buf->alloc - buf->len - 1 /* null byte */); - - const char *error_info = NULL; - switch (xssl_get_error (ctx->ssl, n_read, &error_info)) - { - case SSL_ERROR_NONE: - buf->str[buf->len += n_read] = '\0'; - return IRC_READ_OK; - case SSL_ERROR_ZERO_RETURN: - return IRC_READ_EOF; - case SSL_ERROR_WANT_READ: - return IRC_READ_AGAIN; - case SSL_ERROR_WANT_WRITE: - { - // Let it finish the handshake as we don't poll for writability; - // any errors are to be collected by SSL_read() in the next iteration - struct pollfd pfd = { .fd = ctx->irc_fd, .events = POLLOUT }; - soft_assert (poll (&pfd, 1, 0) > 0); - goto start; - } - case XSSL_ERROR_TRY_AGAIN: - goto start; - default: - print_debug ("%s: %s: %s", __func__, "SSL_read", error_info); - return IRC_READ_ERROR; - } -} - -static enum irc_read_result -irc_fill_read_buffer (struct bot_context *ctx, struct str *buf) -{ - ssize_t n_read; -start: - n_read = recv (ctx->irc_fd, buf->str + buf->len, - buf->alloc - buf->len - 1 /* null byte */, 0); - - if (n_read > 0) - { - buf->str[buf->len += n_read] = '\0'; - return IRC_READ_OK; - } - if (n_read == 0) - return IRC_READ_EOF; - - if (errno == EAGAIN) - return IRC_READ_AGAIN; - if (errno == EINTR) - goto start; - - print_debug ("%s: %s: %s", __func__, "recv", strerror (errno)); - return IRC_READ_ERROR; -} - -static bool irc_connect (struct bot_context *, struct error **); -static void irc_queue_reconnect (struct bot_context *); - -static void -irc_cancel_timers (struct bot_context *ctx) -{ - poller_timer_reset (&ctx->timeout_tmr); - poller_timer_reset (&ctx->ping_tmr); - poller_timer_reset (&ctx->reconnect_tmr); -} - -static void -on_irc_reconnect_timeout (void *user_data) -{ - struct bot_context *ctx = user_data; - - struct error *e = NULL; - if (irc_connect (ctx, &e)) - { - // TODO: inform plugins about the new connection - return; - } - - print_error ("%s", e->message); - error_free (e); - irc_queue_reconnect (ctx); -} - -static void -irc_queue_reconnect (struct bot_context *ctx) -{ - hard_assert (ctx->irc_fd == -1); - print_status ("trying to reconnect in %ld seconds...", - ctx->reconnect_delay); - poller_timer_set (&ctx->reconnect_tmr, ctx->reconnect_delay * 1000); -} - -static void -on_irc_disconnected (struct bot_context *ctx) -{ - // Get rid of the dead socket and related things - if (ctx->ssl) - { - SSL_free (ctx->ssl); - ctx->ssl = NULL; - SSL_CTX_free (ctx->ssl_ctx); - ctx->ssl_ctx = NULL; - } - - poller_fd_reset (&ctx->irc_event); - xclose (ctx->irc_fd); - ctx->irc_fd = -1; - ctx->irc_registered = false; - - // TODO: inform plugins about the disconnect event - - // All of our timers have lost their meaning now - irc_cancel_timers (ctx); - - if (ctx->quitting) - try_finish_quit (ctx); - else if (!ctx->reconnect) - initiate_quit (ctx); - else - irc_queue_reconnect (ctx); -} - -static void -on_irc_ping_timeout (void *user_data) -{ - struct bot_context *ctx = user_data; - print_error ("connection timeout"); - on_irc_disconnected (ctx); -} - -static void -on_irc_timeout (void *user_data) -{ - // Provoke a response from the server - struct bot_context *ctx = user_data; - irc_send (ctx, "PING :%s", - (char *) str_map_find (&ctx->config, "nickname")); -} - -static void -irc_reset_connection_timeouts (struct bot_context *ctx) -{ - irc_cancel_timers (ctx); - poller_timer_set (&ctx->timeout_tmr, 3 * 60 * 1000); - poller_timer_set (&ctx->ping_tmr, (3 * 60 + 30) * 1000); -} - -static void -on_irc_readable (const struct pollfd *fd, struct bot_context *ctx) -{ - if (fd->revents & ~(POLLIN | POLLHUP | POLLERR)) - print_debug ("fd %d: unexpected revents: %d", fd->fd, fd->revents); - - (void) set_blocking (ctx->irc_fd, false); - - struct str *buf = &ctx->read_buffer; - enum irc_read_result (*fill_buffer)(struct bot_context *, struct str *) - = ctx->ssl - ? irc_fill_read_buffer_tls - : irc_fill_read_buffer; - bool disconnected = false; - while (true) - { - str_reserve (buf, 512); - switch (fill_buffer (ctx, buf)) - { - case IRC_READ_AGAIN: - goto end; - case IRC_READ_ERROR: - print_error ("reading from the IRC server failed"); - disconnected = true; - goto end; - case IRC_READ_EOF: - print_status ("the IRC server closed the connection"); - disconnected = true; - goto end; - case IRC_READ_OK: - break; - } - - if (buf->len >= (1 << 20)) - { - print_error ("the IRC server seems to spew out data frantically"); - irc_shutdown (ctx); - goto end; - } - } -end: - (void) set_blocking (ctx->irc_fd, true); - irc_process_buffer (buf, irc_process_message, ctx); - - if (disconnected) - on_irc_disconnected (ctx); - else - irc_reset_connection_timeouts (ctx); -} - -// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -// The bot is currently mostly synchronous (which also makes it shorter), -// however our current SOCKS code is not, hence we must wrap it. - -struct irc_socks_data -{ - struct bot_context *ctx; ///< Bot context - struct poller inner_poller; ///< Special inner poller - bool polling; ///< Inner poller is no longer needed - struct socks_connector connector; ///< SOCKS connector - bool succeeded; ///< Were we successful in connecting? -}; - -static void -irc_on_socks_connected (void *user_data, int socket, const char *hostname) -{ - (void) hostname; - - struct irc_socks_data *data = user_data; - data->ctx->irc_fd = socket; - data->succeeded = true; - data->polling = false; -} - -static void -irc_on_socks_failure (void *user_data) -{ - struct irc_socks_data *data = user_data; - data->succeeded = false; - data->polling = false; -} - -static void -irc_on_socks_connecting (void *user_data, - const char *address, const char *via, const char *version) -{ - (void) user_data; - print_status ("connecting to %s via %s (%s)...", address, via, version); -} - -static void -irc_on_socks_error (void *user_data, const char *error) -{ - (void) user_data; - print_error ("%s: %s", "SOCKS connection failed", error); -} - -static bool -irc_establish_connection_socks (struct bot_context *ctx, - const char *socks_host, const char *socks_port, - const char *host, const char *service, struct error **e) -{ - struct irc_socks_data data; - struct poller *poller = &data.inner_poller; - struct socks_connector *connector = &data.connector; - - data.ctx = ctx; - poller_init (poller); - data.polling = true; - socks_connector_init (connector, poller); - data.succeeded = false; - - connector->on_connected = irc_on_socks_connected; - connector->on_connecting = irc_on_socks_connecting; - connector->on_error = irc_on_socks_error; - connector->on_failure = irc_on_socks_failure; - connector->user_data = &data; - - if (socks_connector_add_target (connector, host, service, e)) - { - socks_connector_run (connector, socks_host, socks_port, - str_map_find (&ctx->config, "socks_username"), - str_map_find (&ctx->config, "socks_password")); - while (data.polling) - poller_run (poller); - if (!data.succeeded) - error_set (e, "connection failed"); - } - - socks_connector_free (connector); - poller_free (poller); - return data.succeeded; -} - -// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -static bool -irc_connect (struct bot_context *ctx, struct error **e) -{ - const char *irc_host = str_map_find (&ctx->config, "irc_host"); - const char *irc_port = str_map_find (&ctx->config, "irc_port"); - const char *socks_host = str_map_find (&ctx->config, "socks_host"); - const char *socks_port = str_map_find (&ctx->config, "socks_port"); - - const char *nickname = str_map_find (&ctx->config, "nickname"); - const char *username = str_map_find (&ctx->config, "username"); - const char *realname = str_map_find (&ctx->config, "realname"); - - // We have a default value for these - hard_assert (irc_port && socks_port); - hard_assert (nickname && username && realname); - - // TODO: again, get rid of `struct error' in here. The question is: how - // do we tell our caller that he should not try to reconnect? - if (!irc_host) - return error_set (e, "no hostname specified in configuration"); - - bool use_tls; - if (!irc_get_boolean_from_config (ctx, "tls", &use_tls, e)) - return false; - - bool connected = socks_host - ? irc_establish_connection_socks (ctx, - socks_host, socks_port, irc_host, irc_port, e) - : irc_establish_connection (ctx, irc_host, irc_port, e); - if (!connected) - return false; - - if (use_tls && !irc_initialize_tls (ctx, e)) - { - xclose (ctx->irc_fd); - ctx->irc_fd = -1; - return false; - } - print_status ("connection established"); - - ctx->irc_event = poller_fd_make (&ctx->poller, ctx->irc_fd); - ctx->irc_event.dispatcher = (poller_fd_fn) on_irc_readable; - ctx->irc_event.user_data = ctx; - - // TODO: in exec try: 1/ set blocking, 2/ setsockopt() SO_LINGER, - // (struct linger) { .l_onoff = true; .l_linger = 1 /* 1s should do */; } - // 3/ /* O_CLOEXEC */ But only if the QUIT message proves unreliable. - poller_fd_set (&ctx->irc_event, POLLIN); - irc_reset_connection_timeouts (ctx); - - irc_send (ctx, "NICK %s", nickname); - irc_send (ctx, "USER %s 8 * :%s", username, realname); - return true; -} - -static bool -parse_config (struct bot_context *ctx, struct error **e) -{ - if (!irc_get_boolean_from_config (ctx, "reconnect", &ctx->reconnect, e)) - return false; - - const char *delay_str = str_map_find (&ctx->config, "reconnect_delay"); - hard_assert (delay_str != NULL); // We have a default value for this - if (!xstrtoul (&ctx->reconnect_delay, delay_str, 10)) - { - return error_set (e, - "invalid configuration value for `%s'", "reconnect_delay"); - } - - hard_assert (!ctx->admin_re); - const char *admin = str_map_find (&ctx->config, "admin"); - if (!admin) - return true; - - struct error *error = NULL; - ctx->admin_re = regex_compile (admin, REG_EXTENDED | REG_NOSUB, &error); - if (!error) - return true; - - error_set (e, "invalid configuration value for `%s': %s", - "admin", error->message); - error_free (error); - return false; -} - -static void -on_plugin_death (struct plugin *plugin, int status) -{ - struct bot_context *ctx = plugin->ctx; - - // TODO: callbacks on children death, so that we may tell the user - // "plugin `name' died like a dirty jewish pig"; use `status' - if (!plugin->is_zombie && WIFSIGNALED (status)) - { - const char *notes = ""; -#ifdef WCOREDUMP - if (WCOREDUMP (status)) - notes = " (core dumped)"; -#endif - print_warning ("Plugin `%s' died from signal %d%s", - plugin->name, WTERMSIG (status), notes); - } - - // Let's go through the zombie state to simplify things a bit - // TODO: might not be a completely bad idea to restart the plugin - plugin_zombify (plugin); - - plugin->pid = -1; - - // In theory we could close `read_fd', set `read_event->closed' to true - // and expect epoll to no longer return events for the descriptor, as - // all the pipe ends should be closed by then (the child is dead, so its - // pipe FDs have been closed [assuming it hasn't forked without closing - // the descriptors, which would be evil], and we would have closed all - // of our FDs for this pipe as well). In practice that doesn't work. - poller_fd_reset (&plugin->read_event); - - xclose (plugin->read_fd); - plugin->read_fd = -1; - - LIST_UNLINK (ctx->plugins, plugin); - plugin_destroy (plugin); - - // Living child processes block us from quitting - try_finish_quit (ctx); -} - -static bool -try_reap_plugin (struct bot_context *ctx) -{ - int status; - pid_t zombie = waitpid (-1, &status, WNOHANG); - - if (zombie == -1) - { - // No children to wait on - if (errno == ECHILD) - return false; - - hard_assert (errno == EINTR); - return true; - } - - if (zombie == 0) - return false; - - struct plugin *plugin = plugin_find_by_pid (ctx, zombie); - // XXX: re-exec if something has died that we don't recognize? - if (soft_assert (plugin != NULL)) - on_plugin_death (plugin, status); - return true; -} - -static void -kill_all_zombies (struct bot_context *ctx) -{ - for (struct plugin *plugin = ctx->plugins; plugin; plugin = plugin->next) - { - if (!plugin->is_zombie) - continue; - - print_status ("forcefully killing a zombie of `%s' (PID %d)", - plugin->name, (int) plugin->pid); - kill (plugin->pid, SIGKILL); - } -} - -static void -on_signal_pipe_readable (const struct pollfd *fd, struct bot_context *ctx) -{ - char dummy; - (void) read (fd->fd, &dummy, 1); - - if (g_termination_requested) - { - g_termination_requested = false; - if (!ctx->quitting) - { - // There may be a timer set to reconnect to the server - irc_cancel_timers (ctx); - - if (ctx->irc_fd != -1) - irc_send (ctx, "QUIT :Terminated by signal"); - initiate_quit (ctx); - } - else - // Disregard proper termination, just kill all the children - kill_all_zombies (ctx); - } - - // Reap all dead children (since the signal pipe may overflow etc. we run - // waitpid() in a loop to return all the zombies it knows about). - while (try_reap_plugin (ctx)) - ; -} - -int -main (int argc, char *argv[]) -{ - g_original_argv = strv_make (); - strv_append_vector (&g_original_argv, argv); - - static const struct opt opts[] = - { - { 'd', "debug", NULL, 0, "run in debug mode" }, - { 'h', "help", NULL, 0, "display this help and exit" }, - { 'V', "version", NULL, 0, "output version information and exit" }, - { 'w', "write-default-cfg", "FILENAME", - OPT_OPTIONAL_ARG | OPT_LONG_ONLY, - "write a default configuration file and exit" }, - { 0, NULL, NULL, 0, NULL } - }; - - struct opt_handler oh = - opt_handler_make (argc, argv, opts, NULL, "Modular IRC bot."); - - int c; - while ((c = opt_handler_get (&oh)) != -1) - switch (c) - { - case 'd': - g_debug_mode = true; - break; - case 'h': - opt_handler_usage (&oh, stdout); - exit (EXIT_SUCCESS); - case 'V': - printf (PROGRAM_NAME " " PROGRAM_VERSION "\n"); - exit (EXIT_SUCCESS); - case 'w': - call_simple_config_write_default (optarg, g_config_table); - exit (EXIT_SUCCESS); - default: - print_error ("wrong options"); - opt_handler_usage (&oh, stderr); - exit (EXIT_FAILURE); - } - - opt_handler_free (&oh); - - print_status (PROGRAM_NAME " " PROGRAM_VERSION " starting"); - setup_signal_handlers (); - init_openssl (); - - struct bot_context ctx; - bot_context_init (&ctx); - - struct error *e = NULL; - if (!simple_config_update_from_file (&ctx.config, &e) - || !setup_recovery_handler (&ctx, &e)) - { - print_error ("%s", e->message); - error_free (e); - exit (EXIT_FAILURE); - } - - ctx.signal_event = poller_fd_make (&ctx.poller, g_signal_pipe[0]); - ctx.signal_event.dispatcher = (poller_fd_fn) on_signal_pipe_readable; - ctx.signal_event.user_data = &ctx; - poller_fd_set (&ctx.signal_event, POLLIN); - -#if OpenBSD >= 201605 - // cpath is for creating the plugin home directory - if (pledge ("stdio rpath cpath inet proc exec", NULL)) - exit_fatal ("%s: %s", "pledge", strerror (errno)); -#endif - - plugin_load_all_from_config (&ctx); - if (!parse_config (&ctx, &e) - || !irc_connect (&ctx, &e)) - { - print_error ("%s", e->message); - error_free (e); - exit (EXIT_FAILURE); - } - - // TODO: clean re-exec support; to save the state I can either use argv, - // argp, or I can create a temporary file, unlink it and use the FD - // (mkstemp() on a `struct str' constructed from XDG_RUNTIME_DIR, TMPDIR - // or /tmp as a last resort + PROGRAM_NAME + ".XXXXXX" -> unlink(); - // remember to use O_CREAT | O_EXCL). The state needs to be versioned. - // Unfortunately I cannot de/serialize SSL state. - - ctx.polling = true; - while (ctx.polling) - poller_run (&ctx.poller); - - bot_context_free (&ctx); - strv_free (&g_original_argv); - return EXIT_SUCCESS; -} - |