--- lbbs/src/net_server.c 2025/05/09 11:21:11 1.19 +++ lbbs/src/net_server.c 2025/11/17 09:46:47 1.91 @@ -1,148 +1,832 @@ -/*************************************************************************** - net_server.c - description - ------------------- - Copyright : (C) 2004-2025 by Leaflet - Email : leaflet@leafok.com - ***************************************************************************/ - -/*************************************************************************** - * * - * This program is free software; you can redistribute it and/or modify * - * it under the terms of the GNU General Public License as published by * - * the Free Software Foundation; either version 3 of the License, or * - * (at your option) any later version. * - * * - ***************************************************************************/ - -#define _XOPEN_SOURCE 500 -#define _POSIX_C_SOURCE 200809L -#define _GNU_SOURCE - -#include "net_server.h" +/* SPDX-License-Identifier: GPL-3.0-or-later */ +/* + * net_server + * - network server with SSH support + * + * Copyright (C) 2004-2025 Leaflet + */ + +#ifdef HAVE_CONFIG_H +#include "config.h" +#endif + +#include "bbs.h" +#include "bbs_main.h" +#include "bwf.h" #include "common.h" -#include "log.h" +#include "database.h" +#include "file_loader.h" +#include "hash_dict.h" #include "io.h" -#include "fork.h" -#include "tcplib.h" +#include "init.h" +#include "log.h" +#include "login.h" #include "menu.h" +#include "net_server.h" +#include "section_list.h" +#include "section_list_loader.h" +#include +#include +#include #include +#include +#include #include -#include +#include +#include +#include +#include +#include +#include +#include #include +#include #include -#include -int net_server(const char *hostaddr, in_port_t port) +#ifdef HAVE_SYS_EPOLL_H +#include +#else +#include +#endif + +#ifdef HAVE_SYSTEMD_SD_DAEMON_H +#include +#endif + +enum _net_server_constant_t +{ + WAIT_CHILD_PROCESS_EXIT_TIMEOUT = 5, // second + WAIT_CHILD_PROCESS_KILL_TIMEOUT = 1, // second + + SSH_AUTH_MAX_DURATION = 60 * 1000, // milliseconds +}; + +/* A userdata struct for session. */ +struct session_data_struct { - unsigned int namelen; + int tries; + int error; +}; + +/* A userdata struct for channel. */ +struct channel_data_struct +{ + /* pid of the child process the channel will spawn. */ + pid_t pid; + /* For PTY allocation */ + socket_t pty_master; + socket_t pty_slave; + /* For communication with the child process. */ + socket_t child_stdin; + socket_t child_stdout; + /* Only used for subsystem and exec requests. */ + socket_t child_stderr; + /* Event which is used to poll the above descriptors. */ + ssh_event event; + /* Terminal size struct. */ + struct winsize *winsize; +}; + +static int socket_server[2]; +static int socket_client; + +#ifdef HAVE_SYS_EPOLL_H +static int epollfd_server = -1; +#endif + +static ssh_bind sshbind; + +static HASH_DICT *hash_dict_pid_sockaddr = NULL; +static HASH_DICT *hash_dict_sockaddr_count = NULL; + +static const char SFTP_SERVER_PATH[] = "/usr/lib/sftp-server"; + +static int auth_password(ssh_session session, const char *user, + const char *password, void *userdata) +{ + struct session_data_struct *sdata = (struct session_data_struct *)userdata; int ret; - int flags; - struct sockaddr_in sin; - fd_set testfds; - struct timeval timeout; - sigset_t nsigset; - sigset_t osigset; - siginfo_t siginfo; - socket_server = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP); + if (strcmp(user, "guest") == 0) + { + ret = load_guest_info(); + } + else + { + ret = check_user(user, password); + } + + if (ret == 0) + { + return SSH_AUTH_SUCCESS; + } + + if ((++(sdata->tries)) >= BBS_login_retry_times) + { + sdata->error = 1; + } + + return SSH_AUTH_DENIED; +} + +static int pty_request(ssh_session session, ssh_channel channel, const char *term, + int cols, int rows, int px, int py, void *userdata) +{ + struct channel_data_struct *cdata = (struct channel_data_struct *)userdata; + int rc; + + (void)session; + (void)channel; + (void)term; + + cdata->winsize->ws_row = (unsigned short int)rows; + cdata->winsize->ws_col = (unsigned short int)cols; + cdata->winsize->ws_xpixel = (unsigned short int)px; + cdata->winsize->ws_ypixel = (unsigned short int)py; + + rc = openpty(&cdata->pty_master, &cdata->pty_slave, NULL, NULL, cdata->winsize); + if (rc != 0) + { + log_error("Failed to open pty\n"); + return SSH_ERROR; + } + + return SSH_OK; +} + +static int pty_resize(ssh_session session, ssh_channel channel, int cols, int rows, + int py, int px, void *userdata) +{ + struct channel_data_struct *cdata = (struct channel_data_struct *)userdata; + + (void)session; + (void)channel; + + cdata->winsize->ws_row = (unsigned short int)rows; + cdata->winsize->ws_col = (unsigned short int)cols; + cdata->winsize->ws_xpixel = (unsigned short int)px; + cdata->winsize->ws_ypixel = (unsigned short int)py; + + if (cdata->pty_master != -1) + { + return ioctl(cdata->pty_master, TIOCSWINSZ, cdata->winsize); + } + + return SSH_ERROR; +} + +static int exec_pty(const char *mode, const char *command, struct channel_data_struct *cdata) +{ + (void)cdata; + + if (command != NULL) + { + log_error("Forbid exec /bin/sh %s %s)\n", mode, command); + } + + return SSH_OK; +} + +static int exec_nopty(const char *command, struct channel_data_struct *cdata) +{ + (void)cdata; + + if (command != NULL) + { + log_error("Forbid exec /bin/sh -c %s)\n", command); + } + + return SSH_OK; +} + +static int exec_request(ssh_session session, ssh_channel channel, const char *command, void *userdata) +{ + struct channel_data_struct *cdata = (struct channel_data_struct *)userdata; + + (void)session; + (void)channel; + + if (cdata->pid > 0) + { + return SSH_ERROR; + } + + if (cdata->pty_master != -1 && cdata->pty_slave != -1) + { + return exec_pty("-c", command, cdata); + } + return exec_nopty(command, cdata); +} + +static int shell_request(ssh_session session, ssh_channel channel, void *userdata) +{ + struct channel_data_struct *cdata = (struct channel_data_struct *)userdata; + + (void)session; + (void)channel; + + if (cdata->pid > 0) + { + return SSH_ERROR; + } + + if (cdata->pty_master != -1 && cdata->pty_slave != -1) + { + return exec_pty("-l", NULL, cdata); + } + /* Client requested a shell without a pty, let's pretend we allow that */ + return SSH_OK; +} + +static int subsystem_request(ssh_session session, ssh_channel channel, const char *subsystem, void *userdata) +{ + (void)session; + (void)channel; + + log_error("subsystem_request(subsystem=%s)\n", subsystem); + + /* subsystem requests behave similarly to exec requests. */ + if (strcmp(subsystem, "sftp") == 0) + { + return exec_request(session, channel, SFTP_SERVER_PATH, userdata); + } + return SSH_ERROR; +} + +static ssh_channel channel_open(ssh_session session, void *userdata) +{ + (void)userdata; + + if (SSH_channel != NULL) + { + return NULL; + } + + SSH_channel = ssh_channel_new(session); + + return SSH_channel; +} + +static int fork_server(void) +{ + ssh_event event; + long int ssh_timeout = 0; + int pid; + int i; + int ret; + + /* Structure for storing the pty size. */ + struct winsize wsize = { + .ws_row = 0, + .ws_col = 0, + .ws_xpixel = 0, + .ws_ypixel = 0}; + + /* Our struct holding information about the channel. */ + struct channel_data_struct cdata = { + .pid = 0, + .pty_master = -1, + .pty_slave = -1, + .child_stdin = -1, + .child_stdout = -1, + .child_stderr = -1, + .event = NULL, + .winsize = &wsize}; + + struct session_data_struct cb_data = { + .tries = 0, + .error = 0, + }; + + struct ssh_channel_callbacks_struct channel_cb = { + .userdata = &cdata, + .channel_pty_request_function = pty_request, + .channel_pty_window_change_function = pty_resize, + .channel_shell_request_function = shell_request, + .channel_exec_request_function = exec_request, + .channel_subsystem_request_function = subsystem_request}; + + struct ssh_server_callbacks_struct server_cb = { + .userdata = &cb_data, + .auth_password_function = auth_password, + .channel_open_request_session_function = channel_open, + }; + + pid = fork(); + + if (pid > 0) // Parent process + { + SYS_child_process_count++; + log_common("Child process (%d) start\n", pid); + return pid; + } + else if (pid < 0) // Error + { + log_error("fork() error (%d)\n", errno); + return -1; + } + + // Child process +#ifdef HAVE_SYS_EPOLL_H + if (close(epollfd_server) < 0) + { + log_error("close(epollfd_server) error (%d)\n"); + } +#endif + + for (i = 0; i < 2; i++) + { + if (close(socket_server[i]) == -1) + { + log_error("Close server socket failed\n"); + } + } + + hash_dict_destroy(hash_dict_pid_sockaddr); + hash_dict_destroy(hash_dict_sockaddr_count); + + SSH_session = ssh_new(); + + if (SSH_v2) + { + if (ssh_bind_accept_fd(sshbind, SSH_session, socket_client) != SSH_OK) + { + log_error("ssh_bind_accept_fd() error: %s\n", ssh_get_error(SSH_session)); + goto cleanup; + } + + ssh_bind_free(sshbind); + + ssh_timeout = 60; // second + if (ssh_options_set(SSH_session, SSH_OPTIONS_TIMEOUT, &ssh_timeout) < 0) + { + log_error("Error setting SSH options: %s\n", ssh_get_error(SSH_session)); + goto cleanup; + } + + ssh_set_auth_methods(SSH_session, SSH_AUTH_METHOD_PASSWORD); + + ssh_callbacks_init(&server_cb); + ssh_callbacks_init(&channel_cb); + + ssh_set_server_callbacks(SSH_session, &server_cb); + + if (ssh_handle_key_exchange(SSH_session)) + { + log_error("ssh_handle_key_exchange() error: %s\n", ssh_get_error(SSH_session)); + goto cleanup; + } + + event = ssh_event_new(); + ssh_event_add_session(event, SSH_session); + + for (i = 0; i < SSH_AUTH_MAX_DURATION && !SYS_server_exit && !cb_data.error && SSH_channel == NULL; i += 100) + { + ret = ssh_event_dopoll(event, 100); // 0.1 second + if (ret == SSH_ERROR) + { +#ifdef _DEBUG + log_error("ssh_event_dopoll() error: %s\n", ssh_get_error(SSH_session)); +#endif + goto cleanup; + } + } + + if (cb_data.error) + { + log_error("SSH auth error, tried %d times\n", cb_data.tries); + goto cleanup; + } + + ssh_set_channel_callbacks(SSH_channel, &channel_cb); + + do + { + ret = ssh_event_dopoll(event, 100); // 0.1 second + if (ret == SSH_ERROR) + { + ssh_channel_close(SSH_channel); + } + + if (ret == SSH_AGAIN) // loop until SSH connection is fully established + { + /* Executed only once, once the child process starts. */ + cdata.event = event; + break; + } + } while (ssh_channel_is_open(SSH_channel)); + + ssh_timeout = 0; + if (ssh_options_set(SSH_session, SSH_OPTIONS_TIMEOUT, &ssh_timeout) < 0) + { + log_error("Error setting SSH options: %s\n", ssh_get_error(SSH_session)); + goto cleanup; + } + } + + // Redirect Input + if (dup2(socket_client, STDIN_FILENO) == -1) + { + log_error("Redirect stdin to client socket failed\n"); + goto cleanup; + } + + // Redirect Output + if (dup2(socket_client, STDOUT_FILENO) == -1) + { + log_error("Redirect stdout to client socket failed\n"); + goto cleanup; + } + + if (io_init() < 0) + { + log_error("io_init() error\n"); + goto cleanup; + } + + SYS_child_process_count = 0; + + bbs_main(); + +cleanup: + // Child process exit + SYS_server_exit = 1; + + if (SSH_v2) + { + if (cdata.pty_master != -1) + { + close(cdata.pty_master); + } + if (cdata.child_stdin != -1) + { + close(cdata.child_stdin); + } + if (cdata.child_stdout != -1) + { + close(cdata.child_stdout); + } + if (cdata.child_stderr != -1) + { + close(cdata.child_stderr); + } - if (socket_server < 0) + ssh_channel_free(SSH_channel); + ssh_disconnect(SSH_session); + } + else if (close(socket_client) == -1) { - log_error("Create socket failed\n"); - exit(1); + log_error("Close client socket failed\n"); } - sin.sin_family = AF_INET; - sin.sin_addr.s_addr = - (strnlen(hostaddr, sizeof(hostaddr)) > 0 ? inet_addr(hostaddr) : INADDR_ANY); - sin.sin_port = htons(port); + ssh_free(SSH_session); + ssh_finalize(); + + // Close Input and Output for client + io_cleanup(); + close(STDIN_FILENO); + close(STDOUT_FILENO); + + log_common("Process exit normally\n"); + log_end(); + + _exit(0); + + return 0; +} - if (bind(socket_server, (struct sockaddr *)&sin, sizeof(sin)) < 0) +int net_server(const char *hostaddr, in_port_t port[]) +{ + unsigned int addrlen; + int ret; + int flags_server[2]; + struct sockaddr_in sin; + +#ifdef HAVE_SYS_EPOLL_H + struct epoll_event ev, events[MAX_EVENTS]; +#else + struct pollfd pfds[2]; +#endif + + int nfds; + int notify_child_exit = 0; + time_t tm_notify_child_exit = time(NULL); + MENU_SET bbs_menu_new; + MENU_SET top10_menu_new; + int i, j; + pid_t pid; + int ssh_log_level = SSH_LOG_NOLOG; + +#ifdef HAVE_SYSTEMD_SD_DAEMON_H + int sd_notify_stopping = 0; +#endif + + ssh_init(); + + sshbind = ssh_bind_new(); + + if (ssh_bind_options_set(sshbind, SSH_BIND_OPTIONS_BINDADDR, hostaddr) < 0 || + ssh_bind_options_set(sshbind, SSH_BIND_OPTIONS_BINDPORT, &port) < 0 || + ssh_bind_options_set(sshbind, SSH_BIND_OPTIONS_HOSTKEY, SSH_HOST_KEYFILE) < 0 || + ssh_bind_options_set(sshbind, SSH_BIND_OPTIONS_HOSTKEY_ALGORITHMS, "ssh-rsa,rsa-sha2-512,rsa-sha2-256") < 0 || + ssh_bind_options_set(sshbind, SSH_BIND_OPTIONS_LOG_VERBOSITY, &ssh_log_level) < 0) { - log_error("Bind address %s:%u failed\n", - inet_ntoa(sin.sin_addr), ntohs(sin.sin_port)); - exit(2); + log_error("Error setting SSH bind options: %s\n", ssh_get_error(sshbind)); + ssh_bind_free(sshbind); + return -1; } - if (listen(socket_server, 10) < 0) +#ifdef HAVE_SYS_EPOLL_H + epollfd_server = epoll_create1(0); + if (epollfd_server == -1) { - log_error("Socket listen failed\n"); - exit(3); + log_error("epoll_create1() error (%d)\n", errno); + return -1; } +#endif + + // Server socket + for (i = 0; i < 2; i++) + { + socket_server[i] = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP); + + if (socket_server[i] < 0) + { + log_error("Create socket_server error (%d)\n", errno); + return -1; + } + + sin.sin_family = AF_INET; + sin.sin_addr.s_addr = (hostaddr[0] != '\0' ? inet_addr(hostaddr) : INADDR_ANY); + sin.sin_port = htons(port[i]); + + // Reuse address and port + flags_server[i] = 1; + if (setsockopt(socket_server[i], SOL_SOCKET, SO_REUSEADDR, &flags_server[i], sizeof(flags_server[i])) < 0) + { + log_error("setsockopt SO_REUSEADDR error (%d)\n", errno); + } +#if defined(SO_REUSEPORT) + if (setsockopt(socket_server[i], SOL_SOCKET, SO_REUSEPORT, &flags_server[i], sizeof(flags_server[i])) < 0) + { + log_error("setsockopt SO_REUSEPORT error (%d)\n", errno); + } +#endif + + if (bind(socket_server[i], (struct sockaddr *)&sin, sizeof(sin)) < 0) + { + log_error("Bind address %s:%u error (%d)\n", + inet_ntoa(sin.sin_addr), ntohs(sin.sin_port), errno); + return -1; + } + + if (listen(socket_server[i], 10) < 0) + { + log_error("Telnet socket listen error (%d)\n", errno); + return -1; + } + + log_common("Listening at %s:%u\n", inet_ntoa(sin.sin_addr), ntohs(sin.sin_port)); - strncpy(hostaddr_server, inet_ntoa(sin.sin_addr), sizeof(hostaddr_server) - 1); - hostaddr_server[sizeof(hostaddr_server) - 1] = '\0'; +#ifdef HAVE_SYS_EPOLL_H + ev.events = EPOLLIN; + ev.data.fd = socket_server[i]; + if (epoll_ctl(epollfd_server, EPOLL_CTL_ADD, socket_server[i], &ev) == -1) + { + log_error("epoll_ctl(socket_server[%d]) error (%d)\n", i, errno); + if (close(epollfd_server) < 0) + { + log_error("close(epoll) error (%d)\n"); + } + return -1; + } +#endif - port_server = ntohs(sin.sin_port); - namelen = sizeof(sin); + flags_server[i] = fcntl(socket_server[i], F_GETFL, 0); + fcntl(socket_server[i], F_SETFL, flags_server[i] | O_NONBLOCK); + } - log_std("Listening at %s:%d\n", hostaddr_server, port_server); + hash_dict_pid_sockaddr = hash_dict_create(MAX_CLIENT_LIMIT); + if (hash_dict_pid_sockaddr == NULL) + { + log_error("hash_dict_create(hash_dict_pid_sockaddr) error\n"); + return -1; + } + hash_dict_sockaddr_count = hash_dict_create(MAX_CLIENT_LIMIT); + if (hash_dict_sockaddr_count == NULL) + { + log_error("hash_dict_create(hash_dict_sockaddr_count) error\n"); + return -1; + } - sigemptyset(&nsigset); - sigaddset(&nsigset, SIGHUP); - sigaddset(&nsigset, SIGCHLD); - sigaddset(&nsigset, SIGTERM); + // Startup complete +#ifdef HAVE_SYSTEMD_SD_DAEMON_H + sd_notifyf(0, "READY=1\n" + "STATUS=Listening at %s:%d (Telnet) and %s:%d (SSH2)\n" + "MAINPID=%d", + hostaddr, port[0], hostaddr, port[1], getpid()); +#endif while (!SYS_server_exit || SYS_child_process_count > 0) { - sigprocmask(SIG_BLOCK, &nsigset, &osigset); +#ifdef HAVE_SYSTEMD_SD_DAEMON_H + if (SYS_server_exit && !sd_notify_stopping) + { + sd_notify(0, "STOPPING=1"); + sd_notify_stopping = 1; + } +#endif - while (SYS_child_exit_count > 0) + while ((SYS_child_exit || SYS_server_exit) && SYS_child_process_count > 0) { - siginfo.si_pid = 0; - ret = waitid(P_ALL, 0, &siginfo, WEXITED | WNOHANG); - if (ret == 0 && siginfo.si_pid > 0) + SYS_child_exit = 0; + + pid = waitpid(-1, NULL, WNOHANG); + if (pid > 0) { - SYS_child_exit_count--; + SYS_child_exit = 1; // Retry waitid + SYS_child_process_count--; - log_std("Child process (%d) exited\n", siginfo.si_pid); + log_common("Child process (%d) exited\n", pid); + + if (pid != section_list_loader_pid) + { + j = 0; + ret = hash_dict_get(hash_dict_pid_sockaddr, (uint64_t)pid, (int64_t *)&j); + if (ret < 0) + { + log_error("hash_dict_get(hash_dict_pid_sockaddr, %d) error\n", pid); + } + else + { + ret = hash_dict_inc(hash_dict_sockaddr_count, (uint64_t)j, -1); + if (ret < 0) + { + log_error("hash_dict_inc(hash_dict_sockaddr_count, %d, -1) error\n", j); + } + + ret = hash_dict_del(hash_dict_pid_sockaddr, (uint64_t)pid); + if (ret < 0) + { + log_error("hash_dict_del(hash_dict_pid_sockaddr, %d) error\n", pid); + } + } + } } - else if (ret == 0) + else if (pid == 0) { break; } - else if (ret < 0) + else if (pid < 0) { - log_error("Error in waitid: %d\n", errno); + log_error("Error in waitpid(): %d\n", errno); break; } } - if (SYS_menu_reload) + if (SYS_server_exit && !SYS_child_exit && SYS_child_process_count > 0) { - if (reload_menu(&bbs_menu) < 0) + if (notify_child_exit == 0) { - log_error("Reload menu failed\n"); +#ifdef HAVE_SYSTEMD_SD_DAEMON_H + sd_notifyf(0, "STATUS=Notify %d child process to exit", SYS_child_process_count); + log_common("Notify %d child process to exit\n", SYS_child_process_count); +#endif + + if (kill(-getpid(), SIGTERM) < 0) + { + log_error("Send SIGTERM signal failed (%d)\n", errno); + } + + notify_child_exit = 1; + tm_notify_child_exit = time(NULL); } - else + else if (notify_child_exit == 1 && time(NULL) - tm_notify_child_exit >= WAIT_CHILD_PROCESS_EXIT_TIMEOUT) + { +#ifdef HAVE_SYSTEMD_SD_DAEMON_H + sd_notifyf(0, "STATUS=Kill %d child process", SYS_child_process_count); +#endif + + if (kill(-getpid(), SIGKILL) < 0) + { + log_error("Send SIGKILL signal failed (%d)\n", errno); + } + + notify_child_exit = 2; + tm_notify_child_exit = time(NULL); + } + else if (notify_child_exit == 2 && time(NULL) - tm_notify_child_exit >= WAIT_CHILD_PROCESS_KILL_TIMEOUT) { - log_std("Reload menu successfully\n"); + log_error("Main process prepare to exit without waiting for %d child process any longer\n", SYS_child_process_count); + SYS_child_process_count = 0; } - SYS_menu_reload = 0; } - sigprocmask(SIG_SETMASK, &osigset, NULL); + if (SYS_conf_reload && !SYS_server_exit) + { + SYS_conf_reload = 0; + +#ifdef HAVE_SYSTEMD_SD_DAEMON_H + sd_notify(0, "RELOADING=1"); +#endif + + // Restart log + if (log_restart() < 0) + { + log_error("Restart logging failed\n"); + } + + // Reload configuration + if (load_conf(CONF_BBSD) < 0) + { + log_error("Reload conf failed\n"); + } - FD_ZERO(&testfds); - FD_SET(socket_server, &testfds); + // Reload BWF config + if (bwf_load(CONF_BWF) < 0) + { + log_error("Reload BWF conf failed\n"); + } - timeout.tv_sec = 1; - timeout.tv_usec = 0; + if (load_menu(&bbs_menu_new, CONF_MENU) < 0) + { + unload_menu(&bbs_menu_new); + log_error("Reload bbs menu failed\n"); + } + else + { + unload_menu(&bbs_menu); + memcpy(&bbs_menu, &bbs_menu_new, sizeof(bbs_menu_new)); + log_common("Reload bbs menu successfully\n"); + } - ret = select(FD_SETSIZE, &testfds, NULL, NULL, &timeout); + if (load_menu(&top10_menu_new, CONF_TOP10_MENU) < 0) + { + unload_menu(&top10_menu_new); + log_error("Reload top10 menu failed\n"); + } + else + { + unload_menu(&top10_menu); + top10_menu_new.allow_exit = 1; + memcpy(&top10_menu, &top10_menu_new, sizeof(top10_menu_new)); + log_common("Reload top10 menu successfully\n"); + } + for (int i = 0; i < data_files_load_startup_count; i++) + { + if (load_file(data_files_load_startup[i]) < 0) + { + log_error("load_file(%s) error\n", data_files_load_startup[i]); + } + } + log_common("Reload data files successfully\n"); + + // Load section config and gen_ex + if (load_section_config_from_db(1) < 0) + { + log_error("load_section_config_from_db(1) error\n"); + } + else + { + log_common("Reload section config and gen_ex successfully\n"); + } + + // Notify child processes to reload configuration + if (kill(-getpid(), SIGUSR1) < 0) + { + log_error("Send SIGUSR1 signal failed (%d)\n", errno); + } + +#ifdef HAVE_SYSTEMD_SD_DAEMON_H + sd_notify(0, "READY=1"); +#endif + } + +#ifdef HAVE_SYS_EPOLL_H + nfds = epoll_wait(epollfd_server, events, MAX_EVENTS, 100); // 0.1 second + ret = nfds; +#else + pfds[0].fd = socket_server[0]; + pfds[0].events = POLLIN; + pfds[1].fd = socket_server[1]; + pfds[1].events = POLLIN; + nfds = 2; + ret = poll(pfds, (nfds_t)nfds, 100); // 0.1 second +#endif if (ret < 0) { if (errno != EINTR) { - log_error("Accept connection error: %d\n", errno); +#ifdef HAVE_SYS_EPOLL_H + log_error("epoll_wait() error (%d)\n", errno); +#else + log_error("poll() error (%d)\n", errno); +#endif + break; } continue; } - else if (ret == 0) // timeout - { - continue; - } // Stop accept new connection on exit if (SYS_server_exit) @@ -150,51 +834,117 @@ int net_server(const char *hostaddr, in_ continue; } - if (FD_ISSET(socket_server, &testfds)) + for (int i = 0; i < nfds; i++) { - flags = fcntl(socket_server, F_GETFL, 0); - fcntl(socket_server, F_SETFL, flags | O_NONBLOCK); - while ((socket_client = - accept(socket_server, (struct sockaddr *)&sin, &namelen)) < 0) +#ifdef HAVE_SYS_EPOLL_H + if (events[i].data.fd == socket_server[0] || events[i].data.fd == socket_server[1]) +#else + if ((pfds[i].fd == socket_server[0] || pfds[i].fd == socket_server[1]) && (pfds[i].revents & POLLIN)) +#endif { - if (errno != EWOULDBLOCK && errno != ECONNABORTED && errno != EINTR) +#ifdef HAVE_SYS_EPOLL_H + SSH_v2 = (events[i].data.fd == socket_server[1] ? 1 : 0); +#else + SSH_v2 = (pfds[i].fd == socket_server[1] ? 1 : 0); +#endif + + while (!SYS_server_exit) // Accept all incoming connections until error { - log_error("Accept connection error\n"); - break; + addrlen = sizeof(sin); + socket_client = accept(socket_server[SSH_v2], (struct sockaddr *)&sin, (socklen_t *)&addrlen); + if (socket_client < 0) + { + if (errno == EAGAIN || errno == EWOULDBLOCK) + { + break; + } + else if (errno == EINTR) + { + continue; + } + else + { + log_error("accept(socket_server) error (%d)\n", errno); + break; + } + } + + strncpy(hostaddr_client, inet_ntoa(sin.sin_addr), sizeof(hostaddr_client) - 1); + hostaddr_client[sizeof(hostaddr_client) - 1] = '\0'; + + port_client = ntohs(sin.sin_port); + + log_common("Accept %s connection from %s:%d\n", (SSH_v2 ? "SSH" : "telnet"), hostaddr_client, port_client); + + if (SYS_child_process_count - 1 < BBS_max_client) + { + j = 0; + ret = hash_dict_get(hash_dict_sockaddr_count, (uint64_t)sin.sin_addr.s_addr, (int64_t *)&j); + if (ret < 0) + { + log_error("hash_dict_get(hash_dict_sockaddr_count, %s) error\n", hostaddr_client); + } + + if (j < BBS_max_client_per_ip) + { + if ((pid = fork_server()) < 0) + { + log_error("fork_server() error\n"); + } + else if (pid > 0) + { + ret = hash_dict_set(hash_dict_pid_sockaddr, (uint64_t)pid, sin.sin_addr.s_addr); + if (ret < 0) + { + log_error("hash_dict_set(hash_dict_pid_sockaddr, %d, %s) error\n", pid, hostaddr_client); + } + + ret = hash_dict_inc(hash_dict_sockaddr_count, (uint64_t)sin.sin_addr.s_addr, 1); + if (ret < 0) + { + log_error("hash_dict_inc(hash_dict_sockaddr_count, %s, %d) error\n", hostaddr_client, 1); + } + } + } + else + { + log_error("Rejected client connection from %s over limit per IP (%d)\n", hostaddr_client, BBS_max_client_per_ip); + } + } + else + { + log_error("Rejected client connection over limit (%d)\n", SYS_child_process_count - 1); + } + + if (close(socket_client) == -1) + { + log_error("close(socket_lient) error (%d)\n", errno); + } } } - fcntl(socket_server, F_SETFL, flags); - } - - if (socket_client < 0) - { - log_error("Accept connection error\n"); - continue; } + } - strncpy(hostaddr_client, inet_ntoa(sin.sin_addr), sizeof(hostaddr_client) - 1); - hostaddr_client[sizeof(hostaddr_client) - 1] = '\0'; - - port_client = ntohs(sin.sin_port); - - log_std("Accept connection from %s:%d\n", hostaddr_client, - port_client); - - if (fork_server() < 0) - { - log_error("Fork error\n"); - } +#ifdef HAVE_SYS_EPOLL_H + if (close(epollfd_server) < 0) + { + log_error("close(epollfd_server) error (%d)\n"); + } +#endif - if (close(socket_client) == -1) + for (i = 0; i < 2; i++) + { + if (close(socket_server[i]) == -1) { - log_error("Close client socket failed\n"); + log_error("Close server socket failed\n"); } } - if (close(socket_server) == -1) - { - log_error("Close server socket failed\n"); - } + hash_dict_destroy(hash_dict_pid_sockaddr); + hash_dict_destroy(hash_dict_sockaddr_count); + + ssh_bind_free(sshbind); + ssh_finalize(); return 0; }