/* bftpd Copyright (C) 1999-2003 Max-Wilhelm Bruker This program is is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License, version 2 of the License as published by the Free Software Foundation. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. */ #include #include #ifdef HAVE_SYS_TYPES_H #include #endif #ifdef HAVE_SYS_STAT_H #include #endif #ifdef HAVE_SYS_SOCKET_H #include #endif #ifdef HAVE_NETINET_IN_H #include #endif #ifdef HAVE_ARPA_INET_H #include #endif #ifdef HAVE_ASM_SOCKET_H #include #endif #include #include #include #include #include #include #include #include #ifdef HAVE_WAIT_H # include #else # ifdef HAVE_SYS_WAIT_H # include # endif #endif #include "main.h" #include "cwd.h" #include "mystring.h" #include "logging.h" #include "dirlist.h" #include "bftpdutmp.h" #include "options.h" #include "login.h" #include "list.h" int global_argc; char **global_argv; char **my_argv_list; // jesse struct sockaddr_in name; int isparent = 1; int listensocket, sock; FILE *passwdfile = NULL, *groupfile = NULL, *devnull; struct sockaddr_in remotename; char *remotehostname; int control_timeout, data_timeout; int alarm_type = 0; struct bftpd_list_element *child_list; /* Command line parameters */ char *configpath = PATH_BFTPD_CONF; int daemonmode = 0; void print_file(int number, char *filename) { FILE *phile; char foo[MAX_STRING_LENGTH]; phile = fopen(filename, "r"); if (phile) { while (fgets(foo, MAX_STRING_LENGTH, phile)) { foo[strlen(foo) - 1] = '\0'; control_printf(SL_SUCCESS, "%i-%s", number, foo); } fclose(phile); } } void end_child() { if (passwdfile) fclose(passwdfile); if (groupfile) fclose(groupfile); config_end(); bftpd_log("Quitting.\n"); bftpd_statuslog(1, 0, "quit"); bftpdutmp_end(); log_end(); login_end(); bftpd_cwd_end(); if (daemonmode) { close(sock); close(0); close(1); close(2); } } /* This function causes the program to re-read parts of the config file. -- Jesse */ void handler_sighup(int sig) { bftpd_log("Caught HUP signal. Re-reading config file.\n"); Reread_Config_File(); signal(sig, handler_sighup); } void handler_sigchld(int sig) { pid_t pid; int i; struct bftpd_childpid *childpid; /* Get the child's return code so that the zombie dies */ pid = wait(NULL); for (i = 0; i < bftpd_list_count(child_list); i++) { childpid = bftpd_list_get(child_list, i); if ( (childpid) && (childpid->pid == pid) ) { close(childpid->sock); bftpd_list_del(&child_list, i); free(childpid); /* make sure the child is removed from the log */ bftpdutmp_remove_pid(pid); } } } void handler_sigterm(int signum) { bftpdutmp_end(); exit(0); /* Force normal termination so that end_child() is called */ } void handler_sigalrm(int signum) { /* Log user out. -- Jesse */ bftpdutmp_end(); if (alarm_type) { close(alarm_type); bftpd_log("Kicked from the server due to data connection timeout.\n"); control_printf(SL_FAILURE, "421 Kicked from the server due to data connection timeout."); exit(0); } else { bftpd_log("Kicked from the server due to control connection timeout.\n"); control_printf(SL_FAILURE, "421 Kicked from the server due to control connection timeout."); exit(0); } } void init_everything() { if (!daemonmode) { config_init(); hidegroups_init(); } log_init(); bftpdutmp_init(); login_init(); } int main(int argc, char **argv) { char str[MAX_STRING_LENGTH + 1]; static struct hostent *he; int i = 1, port; int retval; unsigned long get_value; socklen_t my_length; char *temp_string = NULL; my_argv_list = argv; signal(SIGHUP, handler_sighup); while (((retval = getopt(argc, argv, "c:hdDin"))) > -1) { switch (retval) { case 'h': printf( "Usage: %s [-h] [-i|-d|-D] [-c |-n]\n" "-h print this help\n" "-i (default) run from inetd\n" "-d daemon mode: fork() and run in TCP listen mode\n" "-D run in TCP listen mode, but don't pre-fork()\n" "-c read the config file named \"filename\" instead of " PATH_BFTPD_CONF "\n" "-n no config file, use defaults\n", argv[0]); return 0; case 'i': daemonmode = 0; break; case 'd': daemonmode = 1; break; case 'D': daemonmode = 2; break; case 'c': configpath = strdup(optarg); break; case 'n': configpath = NULL; break; } } if (daemonmode) { struct sockaddr_in myaddr, new; if (daemonmode == 1) { if (fork()) exit(0); /* Exit from parent process */ setsid(); if (fork()) return 0; } signal(SIGCHLD, handler_sigchld); config_init(); chdir("/"); hidegroups_init(); listensocket = socket(AF_INET, SOCK_STREAM, 0); #ifdef SO_REUSEADDR setsockopt(listensocket, SOL_SOCKET, SO_REUSEADDR, (void *) &i, sizeof(i)); #endif #ifdef SO_REUSEPORT setsockopt(listensocket, SOL_SOCKET, SO_REUSEPORT, (void *) &i, sizeof(i)); #endif memset((void *) &myaddr, 0, sizeof(myaddr)); if (!((port = strtoul(config_getoption("PORT"), NULL, 10)))) port = DEFAULT_PORT; myaddr.sin_port = htons(port); if (!strcasecmp(config_getoption("BIND_TO_ADDR"), "any") || !config_getoption("BIND_TO_ADDR")[0]) myaddr.sin_addr.s_addr = INADDR_ANY; else myaddr.sin_addr.s_addr = inet_addr(config_getoption("BIND_TO_ADDR")); if (bind(listensocket, (struct sockaddr *) &myaddr, sizeof(myaddr)) < 0) { fprintf(stderr, "Bind failed: %s\n", strerror(errno)); exit(1); } if (listen(listensocket, 5)) { fprintf(stderr, "Listen failed: %s\n", strerror(errno)); exit(1); } for (i = 0; i < 3; i++) { close(i); /* Remove fd pointing to the console */ open("/dev/null", O_RDWR); /* Create fd pointing nowhere */ } my_length = sizeof(new); while ((sock = accept(listensocket, (struct sockaddr *) &new, &my_length))) { pid_t pid; /* If accept() becomes interrupted by SIGCHLD, it will return -1. * So in order not to create a child process when that happens, * we have to check if accept() returned an error. */ if (sock > 0) { pid = fork(); if (!pid) { /* child */ close(0); close(1); close(2); isparent = 0; dup2(sock, fileno(stdin)); dup2(sock, fileno(stderr)); break; } else { /* parent */ struct bftpd_childpid *tmp_pid = malloc(sizeof(struct bftpd_childpid)); tmp_pid->pid = pid; tmp_pid->sock = sock; bftpd_list_add(&child_list, tmp_pid); } } } } /* Child only. From here on... */ devnull = fopen("/dev/null", "w"); global_argc = argc; global_argv = argv; init_everything(); atexit(end_child); signal(SIGTERM, handler_sigterm); signal(SIGALRM, handler_sigalrm); /* If we do not have getpwnam() for some reason, then we must use FILE_AUTH or exit. */ #ifdef NO_GETPWNAM { char *file_auth_option; file_auth_option = config_getoption("FILE_AUTH"); if (! file_auth_option[0] ) { bftpd_log("Exiting, becasue we have no way to authorize clients.\n"); exit(0); } } #endif get_value = strtoul(config_getoption("CONTROL_TIMEOUT"), NULL, 0); if (get_value <= INT_MAX) control_timeout = get_value; else control_timeout = 0; if (!control_timeout) control_timeout = CONTROL_TIMEOUT; get_value = strtoul(config_getoption("DATA_TIMEOUT"), NULL, 0); if (get_value <= INT_MAX) data_timeout = get_value; else data_timeout = 0; if (!data_timeout) data_timeout = DATA_TIMEOUT; get_value = strtoul(config_getoption("XFER_BUFSIZE"), NULL, 0); if (get_value <= INT_MAX) xfer_bufsize = get_value; else xfer_bufsize = 9; /* handled below if (!xfer_bufsize) xfer_bufsize = XFER_BUFSIZE; */ /* do range check on xfer_bufsize, which is an int */ if ( (xfer_bufsize <= 0) || (xfer_bufsize > 1000000) ) xfer_bufsize = XFER_BUFSIZE; /* get scripts to run pre and post write */ pre_write_script = config_getoption("PRE_WRITE_SCRIPT"); if (! pre_write_script[0]) pre_write_script = NULL; post_write_script = config_getoption("POST_WRITE_SCRIPT"); if (! post_write_script[0]) post_write_script = NULL; my_length = sizeof(remotename); if (getpeername(fileno(stderr), (struct sockaddr *) &remotename, &my_length)) { control_printf(SL_FAILURE, "421-Could not get peer IP address.\r\n421 %s.", strerror(errno)); return 0; } i = 1; setsockopt(fileno(stdin), SOL_SOCKET, SO_OOBINLINE, (void *) &i, sizeof(i)); setsockopt(fileno(stdin), SOL_SOCKET, SO_KEEPALIVE, (void *) &i, sizeof(i)); /* If option is set, determine the client FQDN */ if (!strcasecmp((char *) config_getoption("RESOLVE_CLIENT_IP"), "yes")) { if ((he = gethostbyaddr((char *) &remotename.sin_addr, sizeof(struct in_addr), AF_INET))) { if (he->h_name) remotehostname = strdup(he->h_name); else remotehostname = ""; } else { temp_string = inet_ntoa(remotename.sin_addr); if (temp_string) remotehostname = strdup(temp_string); else remotehostname = ""; /* remotehostname = strdup(inet_ntoa(remotename.sin_addr)); */ } } else { temp_string = inet_ntoa(remotename.sin_addr); if (temp_string) remotehostname = strdup(temp_string); else remotehostname = ""; /* remotehostname = strdup(inet_ntoa(remotename.sin_addr)); */ } bftpd_log("Incoming connection from %s.\n", remotehostname); bftpd_statuslog(1, 0, "connect %s", remotehostname); my_length = sizeof(name); getsockname(fileno(stdin), (struct sockaddr *) &name, &my_length); print_file(220, config_getoption("MOTD_GLOBAL")); /* Parse hello message */ strcpy(str, (char *) config_getoption("HELLO_STRING")); replace(str, "%v", VERSION, MAX_STRING_LENGTH); if (strstr(str, "%h")) { if ((he = gethostbyaddr((char *) &name.sin_addr, sizeof(struct in_addr), AF_INET))) replace(str, "%h", he->h_name, MAX_STRING_LENGTH); else replace(str, "%h", (char *) inet_ntoa(name.sin_addr), MAX_STRING_LENGTH); } replace(str, "%i", (char *) inet_ntoa(name.sin_addr), MAX_STRING_LENGTH); control_printf(SL_SUCCESS, "220 %s", str); /* We might not get any data, so let's set an alarm before the first read. -- Jesse */ alarm(control_timeout); /* Read lines from client and execute appropriate commands */ while (fgets(str, MAXCMD, stdin)) { alarm(control_timeout); str[strlen(str) - 2] = 0; bftpd_statuslog(2, 0, "%s", str); #ifdef DEBUG bftpd_log("Processing command: %s\n", str); #endif parsecmd(str); } if (remotehostname) free(remotehostname); return 0; }