X-Git-Url: http://git.tuebingen.mpg.de/?a=blobdiff_plain;f=server.c;h=a023b1526931c1eeeb3fcec7be3a6b6c72662c69;hb=28b9dcf18ec333883fb53e6e7a5920345d2ba9ee;hp=5ea8811f960550c26d9b99a2c0a15b9ac204f7f7;hpb=d79c420304e9ae7e0dec89ca2644f2e04a7134e2;p=paraslash.git diff --git a/server.c b/server.c index 5ea8811f..a023b152 100644 --- a/server.c +++ b/server.c @@ -1,98 +1,81 @@ /* - * Copyright (C) 1997-2008 Andre Noll + * Copyright (C) 1997 Andre Noll * * Licensed under the GPL v2. For licencing details see COPYING. */ /** \file server.c Paraslash's main server. */ - /** - * \mainpage Paraslash API Reference - * - * Starting points for getting an overview: - * - * - The main programs: \ref server.c, \ref audiod.c, \ref client.c, - * \ref audioc.c, \ref fsck.c, - * - Server: \ref server_command, \ref sender, - * - Audio file selector: \ref audio_format_handler, \ref mood, \ref afs_table, - * - Client: \ref receiver, \ref receiver_node, \ref filter, \ref filter_node. - * - * - * The gory details, listed by topic: - * - * - Audio format handlers: \ref mp3_afh.c, \ref ogg_afh.c, \ref aac_afh.c, - * - Decoders: \ref mp3dec.c, \ref oggdec.c, \ref aacdec.c, - * - Volume normalizer: \ref compress.c, - * - Output: \ref alsa_write.c, \ref osx_write.c, - * - http: \ref http_recv.c, \ref http_send.c, - * - ortp: \ref ortp_recv.c, \ref ortp_send.c, - * - dccp: \ref dccp_recv.c, \ref dccp_send.c, - * - Audio file selector: \ref afs.c, \ref aft.c, \ref mood.c, - * - Afs structures: \ref afs_table, \ref audio_file_data, - * \ref afs_info \ref afh_info, - * - Afs tables: \ref aft.c, \ref mood.c, \ref playlist.c, - * \ref attribute.c, \ref score.c, - * - The virtual streaming system: \ref vss.c, \ref chunk_queue.c. + * \mainpage Main data structures and selected APIs: * - * Lower levels: - * - * - Scheduling: \ref sched.c, \ref sched.h, - * - Networking: \ref net.c, - * - File descriptors: \ref fd.c, - * - Signals: \ref signal.c, - * - Daemons: \ref daemon.c, - * - Strings: \ref string.c, \ref string.h, + * - Senders: \ref sender, + * - Audio file selector: \ref afs_info, \ref afs_table, + * - Audio format handler: \ref audio_format_handler, \ref afh_info + * - Receivers/filters/writers: \ref receiver, \ref receiver_node, + * \ref filter, \ref filter_node, \ref writer_node, \ref writer. + * - Scheduling: \ref sched.h, + * - Buffer trees: \ref buffer_tree.h, + * - Sideband API: \ref sideband.h, + * - Crypto: \ref crypt.h, \ref crypt_backend.h, + * - Error subsystem: \ref error.h, + * - Inter process communication: \ref ipc.h, + * - Forward error correction: \ref fec.h, + * - Daemons: \ref daemon.h, + * - Mixer API: \ref mix.h, + * - Interactive sessions: \ref interactive.h, + * - File descriptors: \ref fd.h, + * - Signals: \ref signal.h, + * - Networking: \ref net.h, * - Time: \ref time.c, - * - Spawning processes: \ref exec.c, - * - Inter process communication: \ref ipc.c, - * - The object storage layer: \ref osl.c, - * - Blob tables: \ref blob.c, - * - The error subssystem: \ref error.h. - * - Access control for paraslash senders: \ref acl.c, \ref acl.h. - * - * Low-level data structures: - * - * - Doubly linked lists: \ref list.h, - * - Red-black trees: \ref rbtree.h, \ref rbtree.c, - * - Ring buffer: \ref ringbuffer.c, \ref ringbuffer.h, - * - Hashing: \ref hash.h, \ref sha1.h, \ref sha1.c, - * - Crypto: \ref crypt.c. - * + * - Doubly linked lists: \ref list.h. */ +#include +#include #include -#include +#include +#include +#include +#include +#include +#include #include "para.h" #include "error.h" +#include "crypt.h" #include "server.cmdline.h" #include "afh.h" #include "string.h" #include "afs.h" #include "server.h" +#include "list.h" +#include "send.h" +#include "sched.h" #include "vss.h" #include "config.h" #include "close_on_fork.h" -#include "list.h" -#include "send.h" #include "net.h" #include "daemon.h" #include "ipc.h" #include "fd.h" -#include "sched.h" #include "signal.h" #include "user_list.h" +#include "color.h" +#include "ggo.h" +#include "version.h" + +/** Array of error strings. */ +DEFINE_PARA_ERRLIST; -/** Define the array of error lists needed by para_server. */ -INIT_SERVER_ERRLISTS; +__printf_2_3 void (*para_log)(int, const char*, ...) = daemon_log; /** Shut down non-authorized connections after that many seconds. */ #define ALARM_TIMEOUT 10 /** * Pointer to shared memory area for communication between para_server - * and its children. Exported to vss.c. command.c and to afs. + * and its children. Exported to vss.c, command.c and to afs. */ struct misc_meta_data *mmd; @@ -110,13 +93,11 @@ uint32_t afs_socket_cookie; /** The mutex protecting the shared memory area containing the mmd struct. */ int mmd_mutex; -/* global variables for server-internal use */ -static FILE *logfile; /** The file containing user information (public key, permissions). */ static char *user_list_file = NULL; -static int mmd_shm_id; -static pid_t afs_pid; +static struct sched sched; +static struct signal_task *signal_task; /** The task responsible for server command handling. */ struct server_command_task { @@ -127,57 +108,38 @@ struct server_command_task { /** Argument vector passed to para_server's main function. */ char **argv; /** The command task structure for scheduling. */ - struct task task; + struct task *task; }; /** - * Para_server's log function. + * Return the list of tasks for the server process. + * + * This is called from \a com_tasks(). The helper is necessary since command + * handlers can not access the scheduler structure directly. * - * \param ll The log level. - * \param fmt The format string describing the log message. + * \return A dynamically allocated string that must be freed by the caller. */ -void para_log(int ll, const char* fmt,...) +char *server_get_tasks(void) { - va_list argp; - FILE *outfd; - struct tm *tm; - time_t t1; - char str[MAXLINE] = ""; - pid_t mypid; - - if (ll < conf.loglevel_arg) - return; - outfd = logfile? logfile : stderr; - time(&t1); - tm = localtime(&t1); - strftime(str, MAXLINE, "%b %d %H:%M:%S", tm); - fprintf(outfd, "%s ", str); - if (conf.loglevel_arg <= INFO) - fprintf(outfd, "%i: ", ll); - mypid = getpid(); - if (conf.loglevel_arg <= INFO) - fprintf(outfd, "(%d) ", (int)mypid); - va_start(argp, fmt); - vfprintf(outfd, fmt, argp); - va_end(argp); + return get_task_list(&sched); } /* * setup shared memory area and get mutex for locking */ -static void shm_init(void) +static void init_ipc_or_die(void) { void *shm; - int ret = shm_new(sizeof(struct misc_meta_data)); + int shmid, ret = shm_new(sizeof(struct misc_meta_data)); if (ret < 0) goto err_out; - - ret = shm_attach(ret, ATTACH_RW, &shm); + shmid = ret; + ret = shm_attach(shmid, ATTACH_RW, &shm); + shm_destroy(shmid); if (ret < 0) goto err_out; mmd = shm; - mmd_shm_id = ret; ret = mutex_new(); if (ret < 0) @@ -197,13 +159,21 @@ err_out: exit(EXIT_FAILURE); } -static void parse_config(int override) +/** + * (Re-)read the server configuration files. + * + * \param override Passed to gengetopt to activate the override feature. + * + * This function also re-opens the logfile and sets the global \a + * user_list_file variable. + */ +void parse_config_or_die(int override) { char *home = para_homedir(); - struct stat statbuf; int ret; char *cf; + daemon_close_log(); if (conf.config_file_given) cf = para_strdup(conf.config_file_arg); else @@ -213,26 +183,41 @@ static void parse_config(int override) user_list_file = make_message("%s/.paraslash/server.users", home); else user_list_file = para_strdup(conf.user_list_arg); - ret = stat(cf, &statbuf); - if (ret && conf.config_file_given) { + ret = file_exists(cf); + if (conf.config_file_given && !ret) { ret = -1; - PARA_EMERG_LOG("can not stat config file %s\n", cf); + PARA_EMERG_LOG("can not read config file %s\n", cf); goto out; } - if (!ret) { + if (ret) { int tmp = conf.daemon_given; struct server_cmdline_parser_params params = { .override = override, .initialize = 0, .check_required = 1, .check_ambiguity = 0, - .print_errors = 1 + .print_errors = !conf.daemon_given }; server_cmdline_parser_config_file(cf, &conf, ¶ms); + daemon_set_loglevel(conf.loglevel_arg); conf.daemon_given = tmp; } - if (conf.logfile_given) - logfile = open_log(conf.logfile_arg); + if (conf.logfile_given) { + daemon_set_logfile(conf.logfile_arg); + daemon_open_log_or_die(); + } + + if (daemon_init_colors_or_die(conf.color_arg, color_arg_auto, color_arg_no, + conf.logfile_given)) { + int i; + for (i = 0; i < conf.log_color_given; i++) + daemon_set_log_color_or_die(conf.log_color_arg[i]); + } + daemon_set_flag(DF_LOG_PID); + daemon_set_flag(DF_LOG_LL); + daemon_set_flag(DF_LOG_TIME); + if (conf.log_timing_given) + daemon_set_flag(DF_LOG_TIMING); ret = 1; out: free(cf); @@ -244,35 +229,25 @@ out: exit(EXIT_FAILURE); } -static void signal_pre_select(struct sched *s, struct task *t) -{ - struct signal_task *st = container_of(t, struct signal_task, task); - para_fd_set(st->fd, &s->rfds, &s->max_fileno); -} - /* * called when server gets SIGHUP or when client invokes hup command. */ static void handle_sighup(void) { PARA_NOTICE_LOG("SIGHUP\n"); - close_log(logfile); /* gets reopened if necessary by parse_config */ - logfile = NULL; - parse_config(1); /* reopens log */ + parse_config_or_die(1); /* reopens log */ init_user_list(user_list_file); /* reload user list */ - if (afs_pid) - kill(afs_pid, SIGHUP); + if (mmd->afs_pid) + kill(mmd->afs_pid, SIGHUP); } -static void signal_post_select(struct sched *s, struct task *t) +static int signal_post_select(struct sched *s, __a_unused void *context) { - struct signal_task *st = container_of(t, struct signal_task, task); + int signum = para_next_signal(&s->rfds); - if (!FD_ISSET(st->fd, &s->rfds)) - return; - - st->signum = para_next_signal(); - switch (st->signum) { + switch (signum) { + case 0: + return 0; case SIGHUP: handle_sighup(); break; @@ -282,96 +257,112 @@ static void signal_post_select(struct sched *s, struct task *t) int ret = para_reap_child(&pid); if (ret <= 0) break; - if (pid != afs_pid) + if (pid != mmd->afs_pid) continue; PARA_EMERG_LOG("fatal: afs died\n"); - goto genocide; + kill(0, SIGTERM); + goto cleanup; } break; /* die on sigint/sigterm. Kill all children too. */ case SIGINT: case SIGTERM: - PARA_EMERG_LOG("terminating on signal %d\n", st->signum); -genocide: + PARA_EMERG_LOG("terminating on signal %d\n", signum); kill(0, SIGTERM); + /* + * We must wait for afs because afs catches SIGINT/SIGTERM. + * Before reacting to the signal, afs might want to use the + * shared memory area and the mmd mutex. If we destroy this + * mutex too early and afs tries to lock the shared memory + * area, the call to mutex_lock() will fail and terminate the + * afs process. This leads to dirty osl tables. + * + * There's no such problem with the other children of the + * server process (the command handlers) as these reset their + * SIGINT/SIGTERM handlers to the default action, i.e. these + * processes get killed immediately by the above kill(). + */ + PARA_INFO_LOG("waiting for afs (pid %d) to die\n", + (int)mmd->afs_pid); + waitpid(mmd->afs_pid, NULL, 0); +cleanup: + free(mmd->afd.afhi.chunk_table); + close_listed_fds(); mutex_destroy(mmd_mutex); shm_detach(mmd); - shm_destroy(mmd_shm_id); - exit(EXIT_FAILURE); } + return 0; } static void init_signal_task(void) { - static struct signal_task signal_task_struct, - *st = &signal_task_struct; - - st->task.pre_select = signal_pre_select; - st->task.post_select = signal_post_select; - sprintf(st->task.status, "signal task"); - - st->fd = para_signal_init(); /* always successful */ - - PARA_NOTICE_LOG("setting up signal handlers\n"); - if (para_install_sighandler(SIGINT) < 0) - goto err; - if (para_install_sighandler(SIGTERM) < 0) - goto err; - if (para_install_sighandler(SIGHUP) < 0) - goto err; - if (para_install_sighandler(SIGCHLD) < 0) - goto err; - if (signal(SIGPIPE, SIG_IGN) == SIG_ERR) - goto err; - if (signal(SIGUSR1, SIG_IGN) == SIG_ERR) - goto err; - add_close_on_fork_list(st->fd); - register_task(&st->task); - return; -err: - PARA_EMERG_LOG("could not install signal handlers\n"); - exit(EXIT_FAILURE); + signal_task = signal_init_or_die(); + para_install_sighandler(SIGINT); + para_install_sighandler(SIGTERM); + para_install_sighandler(SIGHUP); + para_install_sighandler(SIGCHLD); + para_sigaction(SIGPIPE, SIG_IGN); + add_close_on_fork_list(signal_task->fd); + signal_task->task = task_register(&(struct task_info) { + .name = "signal", + .pre_select = signal_pre_select, + .post_select = signal_post_select, + .context = signal_task, + + }, &sched); } -static void command_pre_select(struct sched *s, struct task *t) +static void command_pre_select(struct sched *s, void *context) { - struct server_command_task *sct = container_of(t, struct server_command_task, task); + struct server_command_task *sct = context; para_fd_set(sct->listen_fd, &s->rfds, &s->max_fileno); } -static void command_post_select(struct sched *s, struct task *t) +static int command_post_select(struct sched *s, void *context) { - struct server_command_task *sct = container_of(t, struct server_command_task, task); + struct server_command_task *sct = context; int new_fd, ret, i; char *peer_name; pid_t child_pid; + uint32_t *chunk_table; - if (!FD_ISSET(sct->listen_fd, &s->rfds)) - return; - ret = para_accept(sct->listen_fd, NULL, 0); - if (ret < 0) + ret = para_accept(sct->listen_fd, &s->rfds, NULL, 0, &new_fd); + if (ret <= 0) goto out; - new_fd = ret; peer_name = remote_name(new_fd); PARA_INFO_LOG("got connection from %s, forking\n", peer_name); mmd->num_connects++; mmd->active_connections++; - random(); + /* + * The chunk table is a pointer located in the mmd struct that points + * to dynamically allocated memory, i.e. it must be freed by the parent + * and the child. However, as the mmd struct is in a shared memory + * area, there's no guarantee that after the fork this pointer is still + * valid in child context. As it is not used in the child anyway, we + * save it to a local variable before the fork and free the memory via + * that copy in the child directly after the fork. + */ + chunk_table = mmd->afd.afhi.chunk_table; child_pid = fork(); if (child_pid < 0) { ret = -ERRNO_TO_PARA_ERROR(errno); goto out; } if (child_pid) { + /* avoid problems with non-fork-safe PRNGs */ + unsigned char buf[16]; + get_random_bytes_or_die(buf, sizeof(buf)); close(new_fd); /* parent keeps accepting connections */ - return; + return 0; } + /* mmd might already have changed at this point */ + free(chunk_table); alarm(ALARM_TIMEOUT); close_listed_fds(); - para_signal_shutdown(); + signal_shutdown(signal_task); /* * put info on who we are serving into argv[0] to make * client ip visible in top/ps @@ -379,10 +370,12 @@ static void command_post_select(struct sched *s, struct task *t) for (i = sct->argc - 1; i >= 0; i--) memset(sct->argv[i], 0, strlen(sct->argv[i])); sprintf(sct->argv[0], "para_server (serving %s)", peer_name); - return handle_connect(new_fd, peer_name); + handle_connect(new_fd, peer_name); + /* never reached*/ out: if (ret < 0) PARA_CRIT_LOG("%s\n", para_strerror(-ret)); + return 0; } static void init_server_command_task(int argc, char **argv) @@ -392,11 +385,9 @@ static void init_server_command_task(int argc, char **argv) *sct = &server_command_task_struct; PARA_NOTICE_LOG("initializing tcp command socket\n"); - sct->task.pre_select = command_pre_select; - sct->task.post_select = command_post_select; sct->argc = argc; sct->argv = argv; - ret = para_listen(AF_UNSPEC, IPPROTO_TCP, conf.port_arg); + ret = para_listen_simple(IPPROTO_TCP, conf.port_arg); if (ret < 0) goto err; sct->listen_fd = ret; @@ -404,58 +395,47 @@ static void init_server_command_task(int argc, char **argv) if (ret < 0) goto err; add_close_on_fork_list(sct->listen_fd); /* child doesn't need the listener */ - register_task(&sct->task); + sct->task = task_register(&(struct task_info) { + .name = "server command", + .pre_select = command_pre_select, + .post_select = command_post_select, + .context = sct, + }, &sched); return; err: PARA_EMERG_LOG("%s\n", para_strerror(-ret)); exit(EXIT_FAILURE); } -static void init_random_seed(void) -{ - unsigned int seed; - int fd, ret = para_open("/dev/urandom", O_RDONLY, 0); - - if (ret < 0) - goto err; - fd = ret; - ret = read(fd, &seed, sizeof(seed)); - if (ret < 0) { - ret = -ERRNO_TO_PARA_ERROR(errno); - goto out; - } - if (ret != sizeof(seed)) { - ret = -ERRNO_TO_PARA_ERROR(EIO); - goto out; - } - srandom(seed); - ret = 1; -out: - close(fd); - if (ret >= 0) - return; -err: - PARA_EMERG_LOG("can not seed pseudo random number generator: %s\n", - para_strerror(-ret)); - exit(EXIT_FAILURE); -} - -static int init_afs(void) +static int init_afs(int argc, char **argv) { int ret, afs_server_socket[2]; + pid_t afs_pid; + char c; - ret = socketpair(PF_UNIX, SOCK_DGRAM, 0, afs_server_socket); + ret = socketpair(PF_UNIX, SOCK_STREAM, 0, afs_server_socket); if (ret < 0) exit(EXIT_FAILURE); - afs_socket_cookie = para_random((uint32_t)-1); + get_random_bytes_or_die((unsigned char *)&afs_socket_cookie, + sizeof(afs_socket_cookie)); afs_pid = fork(); if (afs_pid < 0) exit(EXIT_FAILURE); - if (!afs_pid) { /* child (afs) */ + if (afs_pid == 0) { /* child (afs) */ + int i; + + for (i = argc - 1; i >= 0; i--) + memset(argv[i], 0, strlen(argv[i])); + sprintf(argv[0], "para_server (afs)"); close(afs_server_socket[0]); afs_init(afs_socket_cookie, afs_server_socket[1]); } + mmd->afs_pid = afs_pid; close(afs_server_socket[1]); + if (read(afs_server_socket[0], &c, 1) <= 0) { + PARA_EMERG_LOG("early afs exit\n"); + exit(EXIT_FAILURE); + } ret = mark_fd_nonblocking(afs_server_socket[0]); if (ret < 0) exit(EXIT_FAILURE); @@ -465,6 +445,15 @@ static int init_afs(void) return afs_server_socket[0]; } +__noreturn static void print_help_and_die(void) +{ + struct ggo_help h = DEFINE_GGO_HELP(server); + bool d = conf.detailed_help_given; + + ggo_print_help(&h, d? GPH_STANDARD_FLAGS_DETAILED : GPH_STANDARD_FLAGS); + exit(0); +} + static void server_init(int argc, char **argv) { struct server_cmdline_parser_params params = { @@ -474,39 +463,66 @@ static void server_init(int argc, char **argv) .check_ambiguity = 0, .print_errors = 1 }; - int afs_socket; + int afs_socket, daemon_pipe = -1; valid_fd_012(); - init_random_seed(); + init_random_seed_or_die(); /* parse command line options */ server_cmdline_parser_ext(argc, argv, &conf, ¶ms); - HANDLE_VERSION_FLAG("server", conf); - para_drop_privileges(conf.user_arg, conf.group_arg); + daemon_set_loglevel(conf.loglevel_arg); + version_handle_flag("server", conf.version_given); + if (conf.help_given || conf.detailed_help_given) + print_help_and_die(); + daemon_set_priority(conf.priority_arg); + daemon_drop_privileges_or_die(conf.user_arg, conf.group_arg); /* parse config file, open log and set defaults */ - parse_config(0); - log_welcome("para_server", conf.loglevel_arg); - shm_init(); /* init mmd struct */ - server_uptime(UPTIME_SET); /* reset server uptime */ + parse_config_or_die(0); + daemon_log_welcome("server"); + init_ipc_or_die(); /* init mmd struct and mmd->lock */ + daemon_set_start_time(); init_user_list(user_list_file); /* become daemon */ if (conf.daemon_given) - daemon_init(); + daemon_pipe = daemonize(true /* parent waits for us */); PARA_NOTICE_LOG("initializing audio format handlers\n"); afh_init(); - mmd->server_pid = getpid(); - init_signal_task(); + + /* + * Although afs uses its own signal handling we must ignore SIGUSR1 + * _before_ the afs child process gets born by init_afs() below. It's + * racy to do this in the child because the parent might send SIGUSR1 + * before the child gets a chance to ignore this signal -- only the + * good die young. + */ + para_sigaction(SIGUSR1, SIG_IGN); + /* + * We have to block SIGCHLD before the afs process is being forked off. + * Otherwise, para_server does not notice if afs dies before the + * SIGCHLD handler has been installed for the parent process by + * init_signal_task() below. + */ + para_block_signal(SIGCHLD); PARA_NOTICE_LOG("initializing the audio file selector\n"); - afs_socket = init_afs(); + afs_socket = init_afs(argc, argv); + init_signal_task(); + para_unblock_signal(SIGCHLD); PARA_NOTICE_LOG("initializing virtual streaming system\n"); - init_vss_task(afs_socket); + init_vss_task(afs_socket, &sched); init_server_command_task(argc, argv); + if (daemon_pipe >= 0) { + if (write(daemon_pipe, "\0", 1) < 0) { + PARA_EMERG_LOG("daemon_pipe: %s", strerror(errno)); + exit(EXIT_FAILURE); + } + close(daemon_pipe); + } PARA_NOTICE_LOG("server init complete\n"); } static void status_refresh(void) { static int prev_uptime = -1, prev_events = -1; - int uptime = server_uptime(UPTIME_GET), ret = 1; + int uptime = daemon_get_uptime(now); if (prev_events != mmd->events) goto out; @@ -521,11 +537,8 @@ out: prev_uptime = uptime; prev_events = mmd->events; mmd->vss_status_flags = mmd->new_vss_status_flags; - if (ret) { - PARA_DEBUG_LOG("%d events, forcing status update\n", - mmd->events); - killpg(0, SIGUSR1); - } + PARA_DEBUG_LOG("%u events, forcing status update\n", mmd->events); + killpg(0, SIGUSR1); } static int server_select(int max_fileno, fd_set *readfds, fd_set *writefds, @@ -551,16 +564,14 @@ static int server_select(int max_fileno, fd_set *readfds, fd_set *writefds, int main(int argc, char *argv[]) { int ret; - static struct sched s = { - .default_timeout = { - .tv_sec = 1, - .tv_usec = 0 - }, - .select_function = server_select - }; + + sched.default_timeout.tv_sec = 1; + sched.select_function = server_select; + server_init(argc, argv); mutex_lock(mmd_mutex); - ret = schedule(&s); + ret = schedule(&sched); + sched_shutdown(&sched); if (ret < 0) { PARA_EMERG_LOG("%s\n", para_strerror(-ret)); exit(EXIT_FAILURE);