--- lbbs/src/net_server.c 2025/05/25 08:10:48 1.40 +++ lbbs/src/net_server.c 2025/06/24 10:01:24 1.65 @@ -14,85 +14,269 @@ * * ***************************************************************************/ -#define _XOPEN_SOURCE 500 -#define _POSIX_C_SOURCE 200809L -#define _GNU_SOURCE - -#include "net_server.h" +#include "bbs.h" +#include "bbs_main.h" #include "common.h" -#include "log.h" +#include "database.h" +#include "file_loader.h" #include "io.h" -#include "fork.h" +#include "init.h" +#include "log.h" +#include "login.h" #include "menu.h" -#include "file_loader.h" +#include "net_server.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 -#include #include -int net_server(const char *hostaddr, in_port_t port) +struct process_sockaddr_t +{ + pid_t pid; + in_addr_t s_addr; +}; +typedef struct process_sockaddr_t PROCESS_SOCKADDR; + +static PROCESS_SOCKADDR process_sockaddr_pool[MAX_CLIENT_LIMIT]; + +#define SSH_AUTH_MAX_DURATION (60 * 1000) // milliseconds + +struct ssl_server_cb_data_t +{ + int tries; + int error; +}; + +static int auth_password(ssh_session session, const char *user, + const char *password, void *userdata) { - unsigned int namelen; + struct ssl_server_cb_data_t *p_data = userdata; int ret; - int flags; - struct sockaddr_in sin; - struct epoll_event ev, events[MAX_EVENTS]; - int nfds, epollfd; - siginfo_t siginfo; - int sd_notify_stopping = 0; - MENU_SET *p_bbs_menu_new; - 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 (socket_server < 0) + if ((++(p_data->tries)) >= BBS_login_retry_times) { - log_error("Create socket failed\n"); + p_data->error = 1; + } + + return SSH_AUTH_DENIED; +} + +static int pty_request(ssh_session session, ssh_channel channel, const char *term, + int x, int y, int px, int py, void *userdata) +{ + return 0; +} + +static int shell_request(ssh_session session, ssh_channel channel, void *userdata) +{ + return 0; +} + +static struct ssh_channel_callbacks_struct channel_cb = { + .channel_pty_request_function = pty_request, + .channel_shell_request_function = shell_request}; + +static ssh_channel new_session_channel(ssh_session session, void *userdata) +{ + if (SSH_channel != NULL) + { + return NULL; + } + + SSH_channel = ssh_channel_new(session); + ssh_callbacks_init(&channel_cb); + ssh_set_channel_callbacks(SSH_channel, &channel_cb); + + return SSH_channel; +} + +static int fork_server(void) +{ + ssh_event event; + int pid; + int i; + int ret; + + struct ssl_server_cb_data_t cb_data = { + .tries = 0, + .error = 0, + }; + + struct ssh_server_callbacks_struct cb = { + .userdata = &cb_data, + .auth_password_function = auth_password, + .channel_open_request_session_function = new_session_channel, + }; + + 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; } - sin.sin_family = AF_INET; - sin.sin_addr.s_addr = (hostaddr[0] != '\0' ? inet_addr(hostaddr) : INADDR_ANY); - sin.sin_port = htons(port); + // Child process + + if (close(socket_server[0]) == -1 || close(socket_server[1]) == -1) + { + log_error("Close server socket failed\n"); + } + + SSH_session = ssh_new(); - // Reuse address and port - flags = 1; - if (setsockopt(socket_server, SOL_SOCKET, SO_REUSEADDR, &flags, sizeof(flags)) < 0) + if (SSH_v2) { - log_error("setsockopt SO_REUSEADDR error (%d)\n", errno); + 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_callbacks_init(&cb); + ssh_set_server_callbacks(SSH_session, &cb); + + if (ssh_handle_key_exchange(SSH_session)) + { + log_error("ssh_handle_key_exchange() error: %s\n", ssh_get_error(SSH_session)); + goto cleanup; + } + ssh_set_auth_methods(SSH_session, SSH_AUTH_METHOD_PASSWORD); + + 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) + { + log_error("ssh_event_dopoll() error: %s\n", ssh_get_error(SSH_session)); + goto cleanup; + } + } + + if (cb_data.error) + { + log_error("SSH auth error, tried %d times\n", cb_data.tries); + goto cleanup; + } } - if (setsockopt(socket_server, SOL_SOCKET, SO_REUSEPORT, &flags, sizeof(flags)) < 0) + + // Redirect Input + close(STDIN_FILENO); + if (dup2(socket_client, STDIN_FILENO) == -1) { - log_error("setsockopt SO_REUSEPORT error (%d)\n", errno); + log_error("Redirect stdin to client socket failed\n"); + goto cleanup; } - if (bind(socket_server, (struct sockaddr *)&sin, sizeof(sin)) < 0) + // Redirect Output + close(STDOUT_FILENO); + if (dup2(socket_client, STDOUT_FILENO) == -1) { - log_error("Bind address %s:%u failed (%d)\n", - inet_ntoa(sin.sin_addr), ntohs(sin.sin_port), errno); - return -1; + log_error("Redirect stdout to client socket failed\n"); + goto cleanup; } - if (listen(socket_server, 10) < 0) + SYS_child_process_count = 0; + + bbs_main(); + +cleanup: + // Child process exit + SYS_server_exit = 1; + + if (SSH_v2) { - log_error("Socket listen failed (%d)\n", errno); - return -1; + ssh_channel_free(SSH_channel); + ssh_disconnect(SSH_session); } + else if (close(socket_client) == -1) + { + log_error("Close client socket failed\n"); + } + + ssh_free(SSH_session); + ssh_finalize(); - strncpy(hostaddr_server, inet_ntoa(sin.sin_addr), sizeof(hostaddr_server) - 1); - hostaddr_server[sizeof(hostaddr_server) - 1] = '\0'; + // Close Input and Output for client + close(STDIN_FILENO); + close(STDOUT_FILENO); - port_server = ntohs(sin.sin_port); - namelen = sizeof(sin); + log_common("Process exit normally\n"); + log_end(); - log_std("Listening at %s:%d\n", hostaddr_server, port_server); + _exit(0); + + return 0; +} + +int net_server(const char *hostaddr, in_port_t port[]) +{ + unsigned int addrlen; + int ret; + int flags[2]; + struct sockaddr_in sin; + struct epoll_event ev, events[MAX_EVENTS]; + int nfds, epollfd; + siginfo_t siginfo; + int sd_notify_stopping = 0; + MENU_SET *p_bbs_menu_new; + int i, j; + pid_t pid; + int ssh_log_level = SSH_LOG_NOLOG; + + 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("Error setting SSH bind options: %s\n", ssh_get_error(sshbind)); + ssh_bind_free(sshbind); + return -1; + } epollfd = epoll_create1(0); if (epollfd < 0) @@ -101,26 +285,68 @@ int net_server(const char *hostaddr, in_ return -1; } - ev.events = EPOLLIN; - ev.data.fd = socket_server; - if (epoll_ctl(epollfd, EPOLL_CTL_ADD, socket_server, &ev) == -1) + // Server socket + for (i = 0; i < 2; i++) { - log_error("epoll_ctl(socket_server) error (%d)\n", errno); - if (close(epollfd) < 0) + socket_server[i] = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP); + + if (socket_server[i] < 0) { - log_error("close(epoll) error (%d)\n"); + 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[i] = 1; + if (setsockopt(socket_server[i], SOL_SOCKET, SO_REUSEADDR, &flags[i], sizeof(flags[i])) < 0) + { + log_error("setsockopt SO_REUSEADDR error (%d)\n", errno); + } + if (setsockopt(socket_server[i], SOL_SOCKET, SO_REUSEPORT, &flags[i], sizeof(flags[i])) < 0) + { + log_error("setsockopt SO_REUSEPORT error (%d)\n", errno); + } + + 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; } - return -1; - } - flags = fcntl(socket_server, F_GETFL, 0); - fcntl(socket_server, F_SETFL, flags | O_NONBLOCK); + 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)); + + ev.events = EPOLLIN; + ev.data.fd = socket_server[i]; + if (epoll_ctl(epollfd, EPOLL_CTL_ADD, socket_server[i], &ev) == -1) + { + log_error("epoll_ctl(socket_server[%d]) error (%d)\n", i, errno); + if (close(epollfd) < 0) + { + log_error("close(epoll) error (%d)\n"); + } + return -1; + } + + flags[i] = fcntl(socket_server[i], F_GETFL, 0); + fcntl(socket_server[i], F_SETFL, flags[i] | O_NONBLOCK); + } // Startup complete sd_notifyf(0, "READY=1\n" - "STATUS=Listening at %s:%d\n" + "STATUS=Listening at %s:%d (Telnet) and %s:%d (SSH2)\n" "MAINPID=%d", - hostaddr_server, port_server, getpid()); + hostaddr, port[0], hostaddr, port[1], getpid()); while (!SYS_server_exit || SYS_child_process_count > 0) { @@ -141,7 +367,24 @@ int net_server(const char *hostaddr, in_ 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", siginfo.si_pid); + + if (siginfo.si_pid != section_list_loader_pid) + { + i = 0; + for (; i < BBS_max_client; i++) + { + if (process_sockaddr_pool[i].pid == siginfo.si_pid) + { + process_sockaddr_pool[i].pid = 0; + break; + } + } + if (i >= BBS_max_client) + { + log_error("Child process (%d) not found in process sockaddr pool\n", siginfo.si_pid); + } + } } else if (ret == 0) { @@ -156,7 +399,7 @@ int net_server(const char *hostaddr, in_ if (SYS_server_exit && !SYS_child_exit && SYS_child_process_count > 0) { - log_std("Notify %d child process to exit\n", SYS_child_process_count); + log_common("Notify %d child process to exit\n", SYS_child_process_count); if (kill(0, SIGTERM) < 0) { log_error("Send SIGTERM signal failed (%d)\n", errno); @@ -165,11 +408,17 @@ int net_server(const char *hostaddr, in_ sd_notifyf(0, "STATUS=Waiting for %d child process to exit", SYS_child_process_count); } - if (SYS_menu_reload && !SYS_server_exit) + if (SYS_conf_reload && !SYS_server_exit) { - SYS_menu_reload = 0; + SYS_conf_reload = 0; sd_notify(0, "RELOADING=1"); + // Reload configuration + if (load_conf(CONF_BBSD) < 0) + { + log_error("Reload conf failed\n"); + } + p_bbs_menu_new = calloc(1, sizeof(MENU_SET)); if (p_bbs_menu_new == NULL) { @@ -185,15 +434,13 @@ int net_server(const char *hostaddr, in_ } else { - log_std("Debug: trie dict nodes used = %d, limit = %d\n", trie_dict_used_nodes(), TRIE_NODE_PER_POOL); - unload_menu(p_bbs_menu); free(p_bbs_menu); p_bbs_menu = p_bbs_menu_new; p_bbs_menu_new = NULL; - log_std("Reload menu successfully\n"); + log_common("Reload menu successfully\n"); } sd_notify(0, "READY=1"); @@ -212,10 +459,20 @@ int net_server(const char *hostaddr, in_ } } - log_std("Reload data files successfully\n"); + log_common("Reload data files successfully\n"); sd_notify(0, "READY=1"); } + if (SYS_section_list_reload && !SYS_server_exit) + { + SYS_section_list_reload = 0; + + if (section_list_loader_reload() < 0) + { + log_error("section_list_loader_reload() failed\n"); + } + } + nfds = epoll_wait(epollfd, events, MAX_EVENTS, 100); // 0.1 second if (nfds < 0) @@ -236,11 +493,14 @@ int net_server(const char *hostaddr, in_ for (int i = 0; i < nfds; i++) { - if (events[i].data.fd == socket_server) + if (events[i].data.fd == socket_server[0] || events[i].data.fd == socket_server[1]) { + SSH_v2 = (events[i].data.fd == socket_server[1] ? 1 : 0); + while (!SYS_server_exit) // Accept all incoming connections until error { - socket_client = accept(socket_server, (struct sockaddr *)&sin, &namelen); + addrlen = sizeof(sin); + socket_client = accept(socket_server[SSH_v2], (struct sockaddr *)&sin, &addrlen); if (socket_client < 0) { if (errno == EAGAIN || errno == EWOULDBLOCK) @@ -263,11 +523,56 @@ int net_server(const char *hostaddr, in_ port_client = ntohs(sin.sin_port); - log_std("Accept connection from %s:%d\n", hostaddr_client, port_client); + 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; + for (i = 0; i < BBS_max_client; i++) + { + if (process_sockaddr_pool[i].pid != 0 && process_sockaddr_pool[i].s_addr == sin.sin_addr.s_addr) + { + j++; + if (j >= BBS_max_client_per_ip) + { + log_common("Too many client connections (%d) from %s\n", j, hostaddr_client); + break; + } + } + } - if (fork_server() < 0) + if (j < BBS_max_client_per_ip) + { + if ((pid = fork_server()) < 0) + { + log_error("fork_server() error\n"); + } + else if (pid > 0) + { + i = 0; + for (; i < BBS_max_client; i++) + { + if (process_sockaddr_pool[i].pid == 0) + { + break; + } + } + + if (i >= BBS_max_client) + { + log_error("Process sockaddr pool depleted\n"); + } + else + { + process_sockaddr_pool[i].pid = pid; + process_sockaddr_pool[i].s_addr = sin.sin_addr.s_addr; + } + } + } + } + else { - log_error("fork_server() error\n"); + log_error("Rejected client connection over limit (%d)\n", SYS_child_process_count - 1); } if (close(socket_client) == -1) @@ -284,12 +589,18 @@ int net_server(const char *hostaddr, in_ log_error("close(epoll) error (%d)\n"); } - fcntl(socket_server, F_SETFL, flags); - - if (close(socket_server) == -1) + for (i = 0; i < 2; i++) { - log_error("Close server socket failed\n"); + fcntl(socket_server[i], F_SETFL, flags[i]); + + if (close(socket_server[i]) == -1) + { + log_error("Close server socket failed\n"); + } } + ssh_bind_free(sshbind); + ssh_finalize(); + return 0; }