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-rw-r--r--zyklonb.c2063
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;
-}
-