/* $NetBSD: ftpd.c,v 1.182 2007/07/23 10:41:05 lukem Exp $ */ /* * Copyright (c) 1997-2004 The NetBSD Foundation, Inc. * All rights reserved. * * This code is derived from software contributed to The NetBSD Foundation * by Luke Mewburn. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by the NetBSD * Foundation, Inc. and its contributors. * 4. Neither the name of The NetBSD Foundation nor the names of its * contributors may be used to endorse or promote products derived * from this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. */ /* * Copyright (c) 1985, 1988, 1990, 1992, 1993, 1994 * The Regents of the University of California. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ /* * Copyright (C) 1997 and 1998 WIDE Project. * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the project nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #include #ifndef lint __COPYRIGHT( "@(#) Copyright (c) 1985, 1988, 1990, 1992, 1993, 1994\n\ The Regents of the University of California. All rights reserved.\n"); #endif /* not lint */ #ifndef lint #if 0 static char sccsid[] = "@(#)ftpd.c 8.5 (Berkeley) 4/28/95"; #else __RCSID("$NetBSD: ftpd.c,v 1.182 2007/07/23 10:41:05 lukem Exp $"); #endif #endif /* not lint */ /* * FTP server. */ #include #include #include #include #include #include #include #include #include #include #define FTP_NAMES #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #ifdef SUPPORT_UTMP #include #endif #ifdef SUPPORT_UTMPX #include #endif #ifdef SKEY #include #endif #ifdef KERBEROS5 #include #include #endif #ifdef LOGIN_CAP #include #endif #ifdef USE_PAM #include #endif #define GLOBAL #include "extern.h" #include "pathnames.h" #include "version.h" static sig_atomic_t transflag; static sig_atomic_t urgflag; int data; int Dflag; int sflag; int stru; /* avoid C keyword */ int mode; int dataport; /* use specific data port */ int dopidfile; /* maintain pid file */ int doutmp; /* update utmp file */ int dowtmp; /* update wtmp file */ int doxferlog; /* syslog/write wu-ftpd style xferlog entries */ int xferlogfd; /* fd to write wu-ftpd xferlog entries to */ int getnameopts; /* flags for use with getname() */ int dropprivs; /* if privileges should or have been dropped */ int mapped; /* IPv4 connection on AF_INET6 socket */ off_t file_size; off_t byte_count; static char ttyline[20]; #ifdef USE_PAM static int auth_pam(struct passwd **, const char *); pam_handle_t *pamh = NULL; #endif #ifdef SUPPORT_UTMP static struct utmp utmp; /* for utmp */ #endif #ifdef SUPPORT_UTMPX static struct utmpx utmpx; /* for utmpx */ #endif static const char *anondir = NULL; static const char *confdir = _DEFAULT_CONFDIR; static char *curname; /* current USER name */ static size_t curname_len; /* length of curname (include NUL) */ #if defined(KERBEROS) || defined(KERBEROS5) int has_ccache = 0; int notickets = 1; char *krbtkfile_env = NULL; char *tty = ttyline; int login_krb5_forwardable_tgt = 0; #endif int epsvall = 0; /* * Timeout intervals for retrying connections * to hosts that don't accept PORT cmds. This * is a kludge, but given the problems with TCP... */ #define SWAITMAX 90 /* wait at most 90 seconds */ #define SWAITINT 5 /* interval between retries */ int swaitmax = SWAITMAX; int swaitint = SWAITINT; enum send_status { SS_SUCCESS, SS_ABORTED, /* transfer aborted */ SS_NO_TRANSFER, /* no transfer made yet */ SS_FILE_ERROR, /* file read error */ SS_DATA_ERROR /* data send error */ }; static int bind_pasv_addr(void); static int checkuser(const char *, const char *, int, int, char **); static int checkaccess(const char *); static int checkpassword(const struct passwd *, const char *); static void end_login(void); static FILE *getdatasock(const char *); static char *gunique(const char *); static void login_utmp(const char *, const char *, const char *, struct sockinet *); static void logremotehost(struct sockinet *); static void lostconn(int); static void toolong(int); static void sigquit(int); static void sigurg(int); static int handleoobcmd(void); static int receive_data(FILE *, FILE *); static int send_data(FILE *, FILE *, const struct stat *, int); static struct passwd *sgetpwnam(const char *); static int write_data(int, char *, size_t, off_t *, struct timeval *, int); static enum send_status send_data_with_read(int, int, const struct stat *, int); static enum send_status send_data_with_mmap(int, int, const struct stat *, int); static void logrusage(const struct rusage *, const struct rusage *); static void logout_utmp(void); int main(int, char *[]); #if defined(KERBEROS) int klogin(struct passwd *, char *, char *, char *); void kdestroy(void); #endif #if defined(KERBEROS5) int k5login(struct passwd *, char *, char *, char *); void k5destroy(void); #endif int main(int argc, char *argv[]) { int ch, on = 1, tos, keepalive; socklen_t addrlen; #ifdef KERBEROS5 krb5_error_code kerror; #endif char *p; const char *xferlogname = NULL; long l; struct sigaction sa; sa_family_t af = AF_UNSPEC; connections = 1; ftpd_debug = 0; logging = 0; pdata = -1; Dflag = 0; sflag = 0; dataport = 0; dopidfile = 1; /* default: DO use a pid file to count users */ doutmp = 0; /* default: Do NOT log to utmp */ dowtmp = 1; /* default: DO log to wtmp */ doxferlog = 0; /* default: Do NOT syslog xferlog */ xferlogfd = -1; /* default: Do NOT write xferlog file */ getnameopts = 0; /* default: xlate addrs to name */ dropprivs = 0; mapped = 0; usedefault = 1; emailaddr = NULL; hostname[0] = '\0'; homedir[0] = '\0'; gidcount = 0; is_oob = 0; version = FTPD_VERSION; /* * LOG_NDELAY sets up the logging connection immediately, * necessary for anonymous ftp's that chroot and can't do it later. */ openlog("ftpd", LOG_PID | LOG_NDELAY, LOG_FTP); while ((ch = getopt(argc, argv, "46a:c:C:Dde:h:HlL:nP:qQrst:T:uUvV:wWX")) != -1) { switch (ch) { case '4': af = AF_INET; break; case '6': af = AF_INET6; break; case 'a': anondir = optarg; break; case 'c': confdir = optarg; break; case 'C': pw = sgetpwnam(optarg); exit(checkaccess(optarg) ? 0 : 1); /* NOTREACHED */ case 'D': Dflag = 1; break; case 'd': case 'v': /* deprecated */ ftpd_debug = 1; break; case 'e': emailaddr = optarg; break; case 'h': strlcpy(hostname, optarg, sizeof(hostname)); break; case 'H': if (gethostname(hostname, sizeof(hostname)) == -1) hostname[0] = '\0'; hostname[sizeof(hostname) - 1] = '\0'; break; case 'l': logging++; /* > 1 == extra logging */ break; case 'L': xferlogname = optarg; break; case 'n': getnameopts = NI_NUMERICHOST; break; case 'P': errno = 0; p = NULL; l = strtol(optarg, &p, 10); if (errno || *optarg == '\0' || *p != '\0' || l < IPPORT_RESERVED || l > IPPORT_ANONMAX) { syslog(LOG_WARNING, "Invalid dataport %s", optarg); dataport = 0; } dataport = (int)l; break; case 'q': dopidfile = 1; break; case 'Q': dopidfile = 0; break; case 'r': dropprivs = 1; break; case 's': sflag = 1; break; case 't': case 'T': syslog(LOG_WARNING, "-%c has been deprecated in favour of ftpd.conf", ch); break; case 'u': doutmp = 1; break; case 'U': doutmp = 0; break; case 'V': if (EMPTYSTR(optarg) || strcmp(optarg, "-") == 0) version = NULL; else version = ftpd_strdup(optarg); break; case 'w': dowtmp = 1; break; case 'W': dowtmp = 0; break; case 'X': doxferlog |= 1; break; default: if (optopt == 'a' || optopt == 'C') exit(1); syslog(LOG_WARNING, "unknown flag -%c ignored", optopt); break; } } if (EMPTYSTR(confdir)) confdir = _DEFAULT_CONFDIR; if (dowtmp) { #ifdef SUPPORT_UTMPX ftpd_initwtmpx(); #endif #ifdef SUPPORT_UTMP ftpd_initwtmp(); #endif } errno = 0; l = sysconf(_SC_LOGIN_NAME_MAX); if (l == -1 && errno != 0) { syslog(LOG_ERR, "sysconf _SC_LOGIN_NAME_MAX: %m"); exit(1); } else if (l <= 0) { syslog(LOG_WARNING, "using conservative LOGIN_NAME_MAX value"); curname_len = _POSIX_LOGIN_NAME_MAX; } else curname_len = (size_t)l; curname = malloc(curname_len); if (curname == NULL) { syslog(LOG_ERR, "malloc: %m"); exit(1); } curname[0] = '\0'; if (Dflag) { int error, fd, i, n, *socks; struct pollfd *fds; struct addrinfo hints, *res, *res0; if (daemon(1, 0) == -1) { syslog(LOG_ERR, "failed to daemonize: %m"); exit(1); } (void)memset(&sa, 0, sizeof(sa)); sa.sa_handler = SIG_IGN; sa.sa_flags = SA_NOCLDWAIT; sigemptyset(&sa.sa_mask); (void)sigaction(SIGCHLD, &sa, NULL); (void)memset(&hints, 0, sizeof(hints)); hints.ai_flags = AI_PASSIVE; hints.ai_family = af; hints.ai_socktype = SOCK_STREAM; error = getaddrinfo(NULL, "ftp", &hints, &res0); if (error) { syslog(LOG_ERR, "getaddrinfo: %s", gai_strerror(error)); exit(1); } for (n = 0, res = res0; res != NULL; res = res->ai_next) n++; if (n == 0) { syslog(LOG_ERR, "no addresses available"); exit(1); } socks = malloc(n * sizeof(int)); fds = malloc(n * sizeof(struct pollfd)); if (socks == NULL || fds == NULL) { syslog(LOG_ERR, "malloc: %m"); exit(1); } for (n = 0, res = res0; res != NULL; res = res->ai_next) { socks[n] = socket(res->ai_family, res->ai_socktype, res->ai_protocol); if (socks[n] == -1) continue; (void)setsockopt(socks[n], SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)); if (bind(socks[n], res->ai_addr, res->ai_addrlen) == -1) { (void)close(socks[n]); continue; } if (listen(socks[n], 12) == -1) { (void)close(socks[n]); continue; } fds[n].fd = socks[n]; fds[n].events = POLLIN; n++; } if (n == 0) { syslog(LOG_ERR, "%m"); exit(1); } freeaddrinfo(res0); if (pidfile(NULL) == -1) syslog(LOG_ERR, "failed to write a pid file: %m"); for (;;) { if (poll(fds, n, INFTIM) == -1) { if (errno == EINTR) continue; syslog(LOG_ERR, "poll: %m"); exit(1); } for (i = 0; i < n; i++) { if (fds[i].revents & POLLIN) { fd = accept(fds[i].fd, NULL, NULL); if (fd == -1) { syslog(LOG_ERR, "accept: %m"); continue; } switch (fork()) { case -1: syslog(LOG_ERR, "fork: %m"); break; case 0: goto child; /* NOTREACHED */ } (void)close(fd); } } } child: (void)dup2(fd, STDIN_FILENO); (void)dup2(fd, STDOUT_FILENO); (void)dup2(fd, STDERR_FILENO); for (i = 0; i < n; i++) (void)close(socks[i]); } memset((char *)&his_addr, 0, sizeof(his_addr)); addrlen = sizeof(his_addr.si_su); if (getpeername(0, (struct sockaddr *)&his_addr.si_su, &addrlen) < 0) { syslog(LOG_ERR, "getpeername (%s): %m",argv[0]); exit(1); } his_addr.su_len = addrlen; memset((char *)&ctrl_addr, 0, sizeof(ctrl_addr)); addrlen = sizeof(ctrl_addr.si_su); if (getsockname(0, (struct sockaddr *)&ctrl_addr, &addrlen) < 0) { syslog(LOG_ERR, "getsockname (%s): %m",argv[0]); exit(1); } ctrl_addr.su_len = addrlen; #ifdef INET6 if (his_addr.su_family == AF_INET6 && IN6_IS_ADDR_V4MAPPED(&his_addr.su_6addr)) { #if 1 /* * IPv4 control connection arrived to AF_INET6 socket. * I hate to do this, but this is the easiest solution. * * The assumption is untrue on SIIT environment. */ struct sockinet tmp_addr; const int off = sizeof(struct in6_addr) - sizeof(struct in_addr); tmp_addr = his_addr; memset(&his_addr, 0, sizeof(his_addr)); his_addr.su_family = AF_INET; his_addr.su_len = sizeof(his_addr.si_su.su_sin); memcpy(&his_addr.su_addr, &tmp_addr.su_6addr.s6_addr[off], sizeof(his_addr.su_addr)); his_addr.su_port = tmp_addr.su_port; tmp_addr = ctrl_addr; memset(&ctrl_addr, 0, sizeof(ctrl_addr)); ctrl_addr.su_family = AF_INET; ctrl_addr.su_len = sizeof(ctrl_addr.si_su.su_sin); memcpy(&ctrl_addr.su_addr, &tmp_addr.su_6addr.s6_addr[off], sizeof(ctrl_addr.su_addr)); ctrl_addr.su_port = tmp_addr.su_port; #else while (fgets(line, sizeof(line), fd) != NULL) { if ((cp = strchr(line, '\n')) != NULL) *cp = '\0'; reply(-530, "%s", line); } (void) fflush(stdout); (void) fclose(fd); reply(530, "Connection from IPv4 mapped address is not supported."); exit(0); #endif mapped = 1; } else #endif /* INET6 */ mapped = 0; #ifdef IP_TOS if (!mapped && his_addr.su_family == AF_INET) { tos = IPTOS_LOWDELAY; if (setsockopt(0, IPPROTO_IP, IP_TOS, (char *)&tos, sizeof(int)) < 0) syslog(LOG_WARNING, "setsockopt (IP_TOS): %m"); } #endif /* if the hostname hasn't been given, attempt to determine it */ if (hostname[0] == '\0') { if (getnameinfo((struct sockaddr *)&ctrl_addr.si_su, ctrl_addr.su_len, hostname, sizeof(hostname), NULL, 0, getnameopts) != 0) (void)gethostname(hostname, sizeof(hostname)); hostname[sizeof(hostname) - 1] = '\0'; } /* set this here so klogin can use it... */ (void)snprintf(ttyline, sizeof(ttyline), "ftp%d", getpid()); (void) freopen(_PATH_DEVNULL, "w", stderr); memset(&sa, 0, sizeof(sa)); sa.sa_handler = SIG_DFL; sa.sa_flags = SA_RESTART; sigemptyset(&sa.sa_mask); (void) sigaction(SIGCHLD, &sa, NULL); sa.sa_handler = sigquit; sa.sa_flags = SA_RESTART; sigfillset(&sa.sa_mask); /* block all sigs in these handlers */ (void) sigaction(SIGHUP, &sa, NULL); (void) sigaction(SIGINT, &sa, NULL); (void) sigaction(SIGQUIT, &sa, NULL); (void) sigaction(SIGTERM, &sa, NULL); sa.sa_handler = lostconn; (void) sigaction(SIGPIPE, &sa, NULL); sa.sa_handler = toolong; (void) sigaction(SIGALRM, &sa, NULL); sa.sa_handler = sigurg; (void) sigaction(SIGURG, &sa, NULL); /* Try to handle urgent data inline */ #ifdef SO_OOBINLINE if (setsockopt(0, SOL_SOCKET, SO_OOBINLINE, (char *)&on, sizeof(on)) < 0) syslog(LOG_WARNING, "setsockopt: %m"); #endif /* Set keepalives on the socket to detect dropped connections. */ #ifdef SO_KEEPALIVE keepalive = 1; if (setsockopt(0, SOL_SOCKET, SO_KEEPALIVE, (char *)&keepalive, sizeof(int)) < 0) syslog(LOG_WARNING, "setsockopt (SO_KEEPALIVE): %m"); #endif #ifdef F_SETOWN if (fcntl(fileno(stdin), F_SETOWN, getpid()) == -1) syslog(LOG_WARNING, "fcntl F_SETOWN: %m"); #endif logremotehost(&his_addr); /* * Set up default state */ data = -1; type = TYPE_A; form = FORM_N; stru = STRU_F; mode = MODE_S; tmpline[0] = '\0'; hasyyerrored = 0; #ifdef KERBEROS5 kerror = krb5_init_context(&kcontext); if (kerror) { syslog(LOG_ERR, "%s when initializing Kerberos context", error_message(kerror)); exit(0); } #endif /* KERBEROS5 */ init_curclass(); curclass.timeout = 300; /* 5 minutes, as per login(1) */ curclass.type = CLASS_REAL; /* If logins are disabled, print out the message. */ if (display_file(_PATH_NOLOGIN, 530)) { reply(530, "System not available."); exit(0); } (void)display_file(conffilename(_NAME_FTPWELCOME), 220); /* reply(220,) must follow */ if (EMPTYSTR(version)) reply(220, "%s FTP server ready.", hostname); else reply(220, "%s FTP server (%s) ready.", hostname, version); if (xferlogname != NULL) { xferlogfd = open(xferlogname, O_WRONLY | O_APPEND | O_CREAT, 0660); if (xferlogfd == -1) syslog(LOG_WARNING, "open xferlog `%s': %m", xferlogname); else doxferlog |= 2; } ftp_loop(); /* NOTREACHED */ } static void lostconn(int signo __unused) { if (ftpd_debug) syslog(LOG_DEBUG, "lost connection"); dologout(1); } static void toolong(int signo __unused) { /* XXXSIGRACE */ reply(421, "Timeout (" LLF " seconds): closing control connection.", (LLT)curclass.timeout); if (logging) syslog(LOG_INFO, "User %s timed out after " LLF " seconds", (pw ? pw->pw_name : "unknown"), (LLT)curclass.timeout); dologout(1); } static void sigquit(int signo) { if (ftpd_debug) syslog(LOG_DEBUG, "got signal %d", signo); dologout(1); } static void sigurg(int signo __unused) { urgflag = 1; } /* * Save the result of a getpwnam. Used for USER command, since * the data returned must not be clobbered by any other command * (e.g., globbing). */ static struct passwd * sgetpwnam(const char *name) { static struct passwd save; struct passwd *p; if ((p = getpwnam(name)) == NULL) return (p); if (save.pw_name) { free((char *)save.pw_name); memset(save.pw_passwd, 0, strlen(save.pw_passwd)); free((char *)save.pw_passwd); free((char *)save.pw_gecos); free((char *)save.pw_dir); free((char *)save.pw_shell); } save = *p; save.pw_name = ftpd_strdup(p->pw_name); save.pw_passwd = ftpd_strdup(p->pw_passwd); save.pw_gecos = ftpd_strdup(p->pw_gecos); save.pw_dir = ftpd_strdup(p->pw_dir); save.pw_shell = ftpd_strdup(p->pw_shell); return (&save); } static int login_attempts; /* number of failed login attempts */ static int askpasswd; /* had USER command, ask for PASSwd */ static int permitted; /* USER permitted */ /* * USER command. * Sets global passwd pointer pw if named account exists and is acceptable; * sets askpasswd if a PASS command is expected. If logged in previously, * need to reset state. If name is "ftp" or "anonymous", the name is not in * _NAME_FTPUSERS, and ftp account exists, set guest and pw, then just return. * If account doesn't exist, ask for passwd anyway. Otherwise, check user * requesting login privileges. Disallow anyone who does not have a standard * shell as returned by getusershell(). Disallow anyone mentioned in the file * _NAME_FTPUSERS to allow people such as root and uucp to be avoided. */ void user(const char *name) { char *class; #ifdef LOGIN_CAP login_cap_t *lc = NULL; #endif class = NULL; if (logged_in) { switch (curclass.type) { case CLASS_GUEST: reply(530, "Can't change user from guest login."); return; case CLASS_CHROOT: reply(530, "Can't change user from chroot user."); return; case CLASS_REAL: if (dropprivs) { reply(530, "Can't change user."); return; } end_login(); break; default: abort(); } } #if defined(KERBEROS) kdestroy(); #endif #if defined(KERBEROS5) k5destroy(); #endif curclass.type = CLASS_REAL; askpasswd = 0; permitted = 0; if (strcmp(name, "ftp") == 0 || strcmp(name, "anonymous") == 0) { /* need `pw' setup for checkaccess() and checkuser () */ if ((pw = sgetpwnam("ftp")) == NULL) reply(530, "User %s unknown.", name); else if (! checkaccess("ftp") || ! checkaccess("anonymous")) reply(530, "User %s access denied.", name); else { curclass.type = CLASS_GUEST; askpasswd = 1; reply(331, "Guest login ok, type your name as password."); } if (!askpasswd) { if (logging) syslog(LOG_NOTICE, "ANONYMOUS FTP LOGIN REFUSED FROM %s", remotehost); end_login(); goto cleanup_user; } name = "ftp"; } else pw = sgetpwnam(name); strlcpy(curname, name, curname_len); /* check user in /etc/ftpusers, and setup class */ permitted = checkuser(_NAME_FTPUSERS, curname, 1, 0, &class); /* check user in /etc/ftpchroot */ #ifdef LOGIN_CAP lc = login_getpwclass(pw); #endif if (checkuser(_NAME_FTPCHROOT, curname, 0, 0, NULL) #ifdef LOGIN_CAP /* Allow login.conf configuration as well */ || login_getcapbool(lc, "ftp-chroot", 0) #endif ) { if (curclass.type == CLASS_GUEST) { syslog(LOG_NOTICE, "Can't change guest user to chroot class; remove entry in %s", _NAME_FTPCHROOT); exit(1); } curclass.type = CLASS_CHROOT; } /* determine default class */ if (class == NULL) { switch (curclass.type) { case CLASS_GUEST: class = ftpd_strdup("guest"); break; case CLASS_CHROOT: class = ftpd_strdup("chroot"); break; case CLASS_REAL: class = ftpd_strdup("real"); break; default: syslog(LOG_ERR, "unknown curclass.type %d; aborting", curclass.type); abort(); } } /* parse ftpd.conf, setting up various parameters */ parse_conf(class); /* if not guest user, check for valid shell */ if (pw == NULL) permitted = 0; else { const char *cp, *shell; if ((shell = pw->pw_shell) == NULL || *shell == 0) shell = _PATH_BSHELL; while ((cp = getusershell()) != NULL) if (strcmp(cp, shell) == 0) break; endusershell(); if (cp == NULL && curclass.type != CLASS_GUEST) permitted = 0; } /* deny quickly (after USER not PASS) if requested */ if (CURCLASS_FLAGS_ISSET(denyquick) && !permitted) { reply(530, "User %s may not use FTP.", curname); if (logging) syslog(LOG_NOTICE, "FTP LOGIN REFUSED FROM %s, %s", remotehost, curname); end_login(); goto cleanup_user; } /* if haven't asked yet (i.e, not anon), ask now */ if (!askpasswd) { askpasswd = 1; #ifdef SKEY if (skey_haskey(curname) == 0) { const char *myskey; myskey = skey_keyinfo(curname); reply(331, "Password [ %s ] required for %s.", myskey ? myskey : "error getting challenge", curname); } else #endif reply(331, "Password required for %s.", curname); } cleanup_user: #ifdef LOGIN_CAP login_close(lc); #endif /* * Delay before reading passwd after first failed * attempt to slow down passwd-guessing programs. */ if (login_attempts) sleep((unsigned) login_attempts); if (class) free(class); } /* * Determine whether something is to happen (allow access, chroot) * for a user. Each line is a shell-style glob followed by * `yes' or `no'. * * For backward compatibility, `allow' and `deny' are synonymns * for `yes' and `no', respectively. * * Each glob is matched against the username in turn, and the first * match found is used. If no match is found, the result is the * argument `def'. If a match is found but without and explicit * `yes'/`no', the result is the opposite of def. * * If the file doesn't exist at all, the result is the argument * `nofile' * * Any line starting with `#' is considered a comment and ignored. * * Returns 0 if the user is denied, or 1 if they are allowed. * * NOTE: needs struct passwd *pw setup before use. */ static int checkuser(const char *fname, const char *name, int def, int nofile, char **retclass) { FILE *fd; int retval; char *word, *perm, *class, *buf, *p; size_t len, line; retval = def; if (retclass != NULL) *retclass = NULL; if ((fd = fopen(conffilename(fname), "r")) == NULL) return nofile; line = 0; for (; (buf = fparseln(fd, &len, &line, NULL, FPARSELN_UNESCCOMM | FPARSELN_UNESCCONT | FPARSELN_UNESCESC)) != NULL; free(buf), buf = NULL) { word = perm = class = NULL; p = buf; if (len < 1) continue; if (p[len - 1] == '\n') p[--len] = '\0'; if (EMPTYSTR(p)) continue; NEXTWORD(p, word); NEXTWORD(p, perm); NEXTWORD(p, class); if (EMPTYSTR(word)) continue; if (!EMPTYSTR(class)) { if (strcasecmp(class, "all") == 0 || strcasecmp(class, "none") == 0) { syslog(LOG_WARNING, "%s line %d: illegal user-defined class `%s' - skipping entry", fname, (int)line, class); continue; } } /* have a host specifier */ if ((p = strchr(word, '@')) != NULL) { unsigned long net, mask, addr; int bits; *p++ = '\0'; /* check against network or CIDR */ if (isdigit((unsigned char)*p) && (bits = inet_net_pton(AF_INET, p, &net, sizeof(net))) != -1) { net = ntohl(net); mask = 0xffffffffU << (32 - bits); addr = ntohl(his_addr.su_addr.s_addr); if ((addr & mask) != net) continue; /* check against hostname glob */ } else if (fnmatch(p, remotehost, FNM_CASEFOLD) != 0) continue; } /* have a group specifier */ if ((p = strchr(word, ':')) != NULL) { gid_t *groups, *ng; int gsize, i, found; if (pw == NULL) continue; /* no match for unknown user */ *p++ = '\0'; groups = NULL; gsize = 16; do { ng = realloc(groups, gsize * sizeof(gid_t)); if (ng == NULL) fatal( "Local resource failure: realloc"); groups = ng; } while (getgrouplist(pw->pw_name, pw->pw_gid, groups, &gsize) == -1); found = 0; for (i = 0; i < gsize; i++) { struct group *g; if ((g = getgrgid(groups[i])) == NULL) continue; if (fnmatch(p, g->gr_name, 0) == 0) { found = 1; break; } } free(groups); if (!found) continue; } /* check against username glob */ if (fnmatch(word, name, 0) != 0) continue; if (perm != NULL && ((strcasecmp(perm, "allow") == 0) || (strcasecmp(perm, "yes") == 0))) retval = 1; else if (perm != NULL && ((strcasecmp(perm, "deny") == 0) || (strcasecmp(perm, "no") == 0))) retval = 0; else retval = !def; if (!EMPTYSTR(class) && retclass != NULL) *retclass = ftpd_strdup(class); free(buf); break; } (void) fclose(fd); return (retval); } /* * Check if user is allowed by /etc/ftpusers * returns 1 for yes, 0 for no * * NOTE: needs struct passwd *pw setup (for checkuser()) */ static int checkaccess(const char *name) { return (checkuser(_NAME_FTPUSERS, name, 1, 0, NULL)); } static void login_utmp(const char *line, const char *name, const char *host, struct sockinet *haddr) { #if defined(SUPPORT_UTMPX) || defined(SUPPORT_UTMP) struct timeval tv; (void)gettimeofday(&tv, NULL); #endif #ifdef SUPPORT_UTMPX if (doutmp) { (void)memset(&utmpx, 0, sizeof(utmpx)); utmpx.ut_tv = tv; utmpx.ut_pid = getpid(); utmpx.ut_id[0] = 'f'; utmpx.ut_id[1] = 't'; utmpx.ut_id[2] = 'p'; utmpx.ut_id[3] = '*'; utmpx.ut_type = USER_PROCESS; (void)strncpy(utmpx.ut_name, name, sizeof(utmpx.ut_name)); (void)strncpy(utmpx.ut_line, line, sizeof(utmpx.ut_line)); (void)strncpy(utmpx.ut_host, host, sizeof(utmpx.ut_host)); (void)memcpy(&utmpx.ut_ss, &haddr->si_su, haddr->su_len); ftpd_loginx(&utmpx); } if (dowtmp) ftpd_logwtmpx(line, name, host, haddr, 0, USER_PROCESS); #endif #ifdef SUPPORT_UTMP if (doutmp) { (void)memset(&utmp, 0, sizeof(utmp)); (void)time(&utmp.ut_time); (void)strncpy(utmp.ut_name, name, sizeof(utmp.ut_name)); (void)strncpy(utmp.ut_line, line, sizeof(utmp.ut_line)); (void)strncpy(utmp.ut_host, host, sizeof(utmp.ut_host)); ftpd_login(&utmp); } if (dowtmp) ftpd_logwtmp(line, name, host); #endif } static void logout_utmp(void) { #ifdef SUPPORT_UTMPX int okwtmpx = dowtmp; #endif #ifdef SUPPORT_UTMP int okwtmp = dowtmp; #endif if (logged_in) { #ifdef SUPPORT_UTMPX if (doutmp) okwtmpx &= ftpd_logoutx(ttyline, 0, DEAD_PROCESS); if (okwtmpx) ftpd_logwtmpx(ttyline, "", "", NULL, 0, DEAD_PROCESS); #endif #ifdef SUPPORT_UTMP if (doutmp) okwtmp &= ftpd_logout(ttyline); if (okwtmp) ftpd_logwtmp(ttyline, "", ""); #endif } } /* * Terminate login as previous user (if any), resetting state; * used when USER command is given or login fails. */ static void end_login(void) { #ifdef USE_PAM int e; #endif logout_utmp(); show_chdir_messages(-1); /* flush chdir cache */ if (pw != NULL && pw->pw_passwd != NULL) memset(pw->pw_passwd, 0, strlen(pw->pw_passwd)); pw = NULL; logged_in = 0; askpasswd = 0; permitted = 0; quietmessages = 0; gidcount = 0; curclass.type = CLASS_REAL; (void) seteuid((uid_t)0); #ifdef LOGIN_CAP setusercontext(NULL, getpwuid(0), 0, LOGIN_SETPRIORITY|LOGIN_SETRESOURCES|LOGIN_SETUMASK); #endif #ifdef USE_PAM if (pamh) { if ((e = pam_setcred(pamh, PAM_DELETE_CRED)) != PAM_SUCCESS) syslog(LOG_ERR, "pam_setcred: %s", pam_strerror(pamh, e)); if ((e = pam_close_session(pamh,0)) != PAM_SUCCESS) syslog(LOG_ERR, "pam_close_session: %s", pam_strerror(pamh, e)); if ((e = pam_end(pamh, e)) != PAM_SUCCESS) syslog(LOG_ERR, "pam_end: %s", pam_strerror(pamh, e)); pamh = NULL; } #endif } void pass(const char *passwd) { int rval; char root[MAXPATHLEN]; #ifdef LOGIN_CAP login_cap_t *lc = NULL; #endif #ifdef USE_PAM int e; #endif if (logged_in || askpasswd == 0) { reply(503, "Login with USER first."); return; } askpasswd = 0; if (curclass.type != CLASS_GUEST) { /* "ftp" is the only account allowed with no password */ if (pw == NULL) { rval = 1; /* failure below */ goto skip; } #ifdef USE_PAM rval = auth_pam(&pw, passwd); #ifdef notdef /* If PAM fails, we proceed with other authentications */ if (rval >= 0) { goto skip; } #else /* If PAM fails, that's it */ goto skip; #endif #endif #if defined(KERBEROS) if (klogin(pw, "", hostname, (char *)passwd) == 0) { rval = 0; goto skip; } #endif #if defined(KERBEROS5) if (k5login(pw, "", hostname, (char *)passwd) == 0) { rval = 0; goto skip; } #endif #ifdef SKEY if (skey_haskey(pw->pw_name) == 0) { char *p; int r; p = ftpd_strdup(passwd); r = skey_passcheck(pw->pw_name, p); free(p); if (r != -1) { rval = 0; goto skip; } } #endif if (!sflag) rval = checkpassword(pw, passwd); else rval = 1; skip: /* * If rval > 0, the user failed the authentication check * above. If rval == 0, either Kerberos or local * authentication succeeded. */ if (rval) { reply(530, "%s", rval == 2 ? "Password expired." : "Login incorrect."); if (logging) { syslog(LOG_NOTICE, "FTP LOGIN FAILED FROM %s", remotehost); syslog(LOG_AUTHPRIV | LOG_NOTICE, "FTP LOGIN FAILED FROM %s, %s", remotehost, curname); } pw = NULL; if (login_attempts++ >= 5) { syslog(LOG_NOTICE, "repeated login failures from %s", remotehost); exit(0); } return; } } /* password ok; check if anything else prevents login */ if (! permitted) { reply(530, "User %s may not use FTP.", pw->pw_name); if (logging) syslog(LOG_NOTICE, "FTP LOGIN REFUSED FROM %s, %s", remotehost, pw->pw_name); goto bad; } login_attempts = 0; /* this time successful */ if (setegid((gid_t)pw->pw_gid) < 0) { reply(550, "Can't set gid."); goto bad; } #ifdef LOGIN_CAP if ((lc = login_getpwclass(pw)) != NULL) { #ifdef notyet char remote_ip[NI_MAXHOST]; if (getnameinfo((struct sockaddr *)&his_addr, his_addr.su_len, remote_ip, sizeof(remote_ip) - 1, NULL, 0, NI_NUMERICHOST)) *remote_ip = 0; remote_ip[sizeof(remote_ip) - 1] = 0; if (!auth_hostok(lc, remotehost, remote_ip)) { syslog(LOG_INFO|LOG_AUTH, "FTP LOGIN FAILED (HOST) as %s: permission denied.", pw->pw_name); reply(530, "Permission denied."); pw = NULL; return; } if (!auth_timeok(lc, time(NULL))) { reply(530, "Login not available right now."); pw = NULL; return; } #endif } setsid(); setusercontext(lc, pw, 0, LOGIN_SETLOGIN|LOGIN_SETGROUP|LOGIN_SETPRIORITY| LOGIN_SETRESOURCES|LOGIN_SETUMASK); #else (void) initgroups(pw->pw_name, pw->pw_gid); /* cache groups for cmds.c::matchgroup() */ #endif #ifdef USE_PAM if (pamh) { if ((e = pam_open_session(pamh, 0)) != PAM_SUCCESS) { syslog(LOG_ERR, "pam_open_session: %s", pam_strerror(pamh, e)); } else if ((e = pam_setcred(pamh, PAM_ESTABLISH_CRED)) != PAM_SUCCESS) { syslog(LOG_ERR, "pam_setcred: %s", pam_strerror(pamh, e)); } } #endif gidcount = getgroups(0, NULL); if (gidlist) free(gidlist); gidlist = malloc(gidcount * sizeof *gidlist); gidcount = getgroups(gidcount, gidlist); /* open utmp/wtmp before chroot */ login_utmp(ttyline, pw->pw_name, remotehost, &his_addr); logged_in = 1; connections = 1; if (dopidfile) count_users(); if (curclass.limit != -1 && connections > curclass.limit) { if (! EMPTYSTR(curclass.limitfile)) (void)display_file(conffilename(curclass.limitfile), 530); reply(530, "User %s access denied, connection limit of " LLF " reached.", pw->pw_name, (LLT)curclass.limit); syslog(LOG_NOTICE, "Maximum connection limit of " LLF " for class %s reached, login refused for %s", (LLT)curclass.limit, curclass.classname, pw->pw_name); goto bad; } homedir[0] = '/'; switch (curclass.type) { case CLASS_GUEST: /* * We MUST do a chdir() after the chroot. Otherwise * the old current directory will be accessible as "." * outside the new root! */ format_path(root, curclass.chroot ? curclass.chroot : anondir ? anondir : pw->pw_dir); format_path(homedir, curclass.homedir ? curclass.homedir : "/"); if (EMPTYSTR(homedir)) homedir[0] = '/'; if (EMPTYSTR(root) || chroot(root) < 0) { syslog(LOG_NOTICE, "GUEST user %s: can't chroot to %s: %m", pw->pw_name, root); goto bad_guest; } if (chdir(homedir) < 0) { syslog(LOG_NOTICE, "GUEST user %s: can't chdir to %s: %m", pw->pw_name, homedir); bad_guest: reply(550, "Can't set guest privileges."); goto bad; } break; case CLASS_CHROOT: format_path(root, curclass.chroot ? curclass.chroot : pw->pw_dir); format_path(homedir, curclass.homedir ? curclass.homedir : "/"); if (EMPTYSTR(homedir)) homedir[0] = '/'; if (EMPTYSTR(root) || chroot(root) < 0) { syslog(LOG_NOTICE, "CHROOT user %s: can't chroot to %s: %m", pw->pw_name, root); goto bad_chroot; } if (chdir(homedir) < 0) { syslog(LOG_NOTICE, "CHROOT user %s: can't chdir to %s: %m", pw->pw_name, homedir); bad_chroot: reply(550, "Can't change root."); goto bad; } break; case CLASS_REAL: /* only chroot REAL if explicitly requested */ if (! EMPTYSTR(curclass.chroot)) { format_path(root, curclass.chroot); if (EMPTYSTR(root) || chroot(root) < 0) { syslog(LOG_NOTICE, "REAL user %s: can't chroot to %s: %m", pw->pw_name, root); goto bad_chroot; } } format_path(homedir, curclass.homedir ? curclass.homedir : pw->pw_dir); if (EMPTYSTR(homedir) || chdir(homedir) < 0) { if (chdir("/") < 0) { syslog(LOG_NOTICE, "REAL user %s: can't chdir to %s: %m", pw->pw_name, !EMPTYSTR(homedir) ? homedir : "/"); reply(530, "User %s: can't change directory to %s.", pw->pw_name, !EMPTYSTR(homedir) ? homedir : "/"); goto bad; } else { reply(-230, "No directory! Logging in with home=/"); homedir[0] = '/'; } } break; } #ifndef LOGIN_CAP setsid(); setlogin(pw->pw_name); #endif if (dropprivs || (curclass.type != CLASS_REAL && ntohs(ctrl_addr.su_port) > IPPORT_RESERVED + 1)) { dropprivs++; if (setgid((gid_t)pw->pw_gid) < 0) { reply(550, "Can't set gid."); goto bad; } if (setuid((uid_t)pw->pw_uid) < 0) { reply(550, "Can't set uid."); goto bad; } } else { if (seteuid((uid_t)pw->pw_uid) < 0) { reply(550, "Can't set uid."); goto bad; } } setenv("HOME", homedir, 1); if (curclass.type == CLASS_GUEST && passwd[0] == '-') quietmessages = 1; /* * Display a login message, if it exists. * N.B. reply(230,) must follow the message. */ if (! EMPTYSTR(curclass.motd)) (void)display_file(conffilename(curclass.motd), 230); show_chdir_messages(230); if (curclass.type == CLASS_GUEST) { char *p; reply(230, "Guest login ok, access restrictions apply."); #if defined(HAVE_SETPROCTITLE) snprintf(proctitle, sizeof(proctitle), "%s: anonymous/%s", remotehost, passwd); setproctitle("%s", proctitle); #endif /* defined(HAVE_SETPROCTITLE) */ if (logging) syslog(LOG_INFO, "ANONYMOUS FTP LOGIN FROM %s, %s (class: %s, type: %s)", remotehost, passwd, curclass.classname, CURCLASSTYPE); /* store guest password reply into pw_passwd */ REASSIGN(pw->pw_passwd, ftpd_strdup(passwd)); for (p = pw->pw_passwd; *p; p++) if (!isgraph((unsigned char)*p)) *p = '_'; } else { reply(230, "User %s logged in.", pw->pw_name); #if defined(HAVE_SETPROCTITLE) snprintf(proctitle, sizeof(proctitle), "%s: %s", remotehost, pw->pw_name); setproctitle("%s", proctitle); #endif /* defined(HAVE_SETPROCTITLE) */ if (logging) syslog(LOG_INFO, "FTP LOGIN FROM %s as %s (class: %s, type: %s)", remotehost, pw->pw_name, curclass.classname, CURCLASSTYPE); } (void) umask(curclass.umask); #ifdef LOGIN_CAP login_close(lc); #endif return; bad: #ifdef LOGIN_CAP login_close(lc); #endif /* Forget all about it... */ end_login(); } void retrieve(char *argv[], const char *name) { FILE *fin, *dout; struct stat st; int (*closefunc)(FILE *) = NULL; int dolog, sendrv, closerv, stderrfd, isconversion, isdata, isls; struct timeval start, finish, td, *tdp; struct rusage rusage_before, rusage_after; const char *dispname; char *error; sendrv = closerv = stderrfd = -1; isconversion = isdata = isls = dolog = 0; tdp = NULL; dispname = name; fin = dout = NULL; error = NULL; if (argv == NULL) { /* if not running a command ... */ dolog = 1; isdata = 1; fin = fopen(name, "r"); closefunc = fclose; if (fin == NULL) /* doesn't exist?; try a conversion */ argv = do_conversion(name); if (argv != NULL) { isconversion++; syslog(LOG_DEBUG, "get command: '%s' on '%s'", argv[0], name); } } if (argv != NULL) { char temp[MAXPATHLEN]; if (strcmp(argv[0], INTERNAL_LS) == 0) { isls = 1; stderrfd = -1; } else { (void)snprintf(temp, sizeof(temp), "%s", TMPFILE); stderrfd = mkstemp(temp); if (stderrfd != -1) (void)unlink(temp); } dispname = argv[0]; fin = ftpd_popen(argv, "r", stderrfd); closefunc = ftpd_pclose; st.st_size = -1; st.st_blksize = BUFSIZ; } if (fin == NULL) { if (errno != 0) { perror_reply(550, dispname); if (dolog) logxfer("get", -1, name, NULL, NULL, strerror(errno)); } goto cleanupretrieve; } byte_count = -1; if (argv == NULL && (fstat(fileno(fin), &st) < 0 || !S_ISREG(st.st_mode))) { error = "Not a plain file"; reply(550, "%s: %s.", dispname, error); goto done; } if (restart_point) { if (type == TYPE_A) { off_t i; int c; for (i = 0; i < restart_point; i++) { if ((c=getc(fin)) == EOF) { error = strerror(errno); perror_reply(550, dispname); goto done; } if (c == '\n') i++; } } else if (lseek(fileno(fin), restart_point, SEEK_SET) < 0) { error = strerror(errno); perror_reply(550, dispname); goto done; } } dout = dataconn(dispname, st.st_size, "w"); if (dout == NULL) goto done; (void)getrusage(RUSAGE_SELF, &rusage_before); (void)gettimeofday(&start, NULL); sendrv = send_data(fin, dout, &st, isdata); (void)gettimeofday(&finish, NULL); (void)getrusage(RUSAGE_SELF, &rusage_after); closedataconn(dout); /* close now to affect timing stats */ timersub(&finish, &start, &td); tdp = &td; done: if (dolog) { logxfer("get", byte_count, name, NULL, tdp, error); if (tdp != NULL) logrusage(&rusage_before, &rusage_after); } closerv = (*closefunc)(fin); if (sendrv == 0) { FILE *errf; struct stat sb; if (!isls && argv != NULL && closerv != 0) { reply(-226, "Command returned an exit status of %d", closerv); if (isconversion) syslog(LOG_WARNING, "retrieve command: '%s' returned %d", argv[0], closerv); } if (!isls && argv != NULL && stderrfd != -1 && (fstat(stderrfd, &sb) == 0) && sb.st_size > 0 && ((errf = fdopen(stderrfd, "r")) != NULL)) { char *cp, line[LINE_MAX]; reply(-226, "Command error messages:"); rewind(errf); while (fgets(line, sizeof(line), errf) != NULL) { if ((cp = strchr(line, '\n')) != NULL) *cp = '\0'; reply(0, " %s", line); } (void) fflush(stdout); (void) fclose(errf); /* a reply(226,) must follow */ } reply(226, "Transfer complete."); } cleanupretrieve: if (stderrfd != -1) (void)close(stderrfd); if (isconversion) free(argv); } void store(const char *name, const char *fmode, int unique) { FILE *fout, *din; struct stat st; int (*closefunc)(FILE *); struct timeval start, finish, td, *tdp; char *desc, *error; din = NULL; desc = (*fmode == 'w') ? "put" : "append"; error = NULL; if (unique && stat(name, &st) == 0 && (name = gunique(name)) == NULL) { logxfer(desc, -1, name, NULL, NULL, "cannot create unique file"); goto cleanupstore; } if (restart_point) fmode = "r+"; fout = fopen(name, fmode); closefunc = fclose; tdp = NULL; if (fout == NULL) { perror_reply(553, name); logxfer(desc, -1, name, NULL, NULL, strerror(errno)); goto cleanupstore; } byte_count = -1; if (restart_point) { if (type == TYPE_A) { off_t i; int c; for (i = 0; i < restart_point; i++) { if ((c=getc(fout)) == EOF) { error = strerror(errno); perror_reply(550, name); goto done; } if (c == '\n') i++; } /* * We must do this seek to "current" position * because we are changing from reading to * writing. */ if (fseek(fout, 0L, SEEK_CUR) < 0) { error = strerror(errno); perror_reply(550, name); goto done; } } else if (lseek(fileno(fout), restart_point, SEEK_SET) < 0) { error = strerror(errno); perror_reply(550, name); goto done; } } din = dataconn(name, (off_t)-1, "r"); if (din == NULL) goto done; (void)gettimeofday(&start, NULL); if (receive_data(din, fout) == 0) { if (unique) reply(226, "Transfer complete (unique file name:%s).", name); else reply(226, "Transfer complete."); } (void)gettimeofday(&finish, NULL); closedataconn(din); /* close now to affect timing stats */ timersub(&finish, &start, &td); tdp = &td; done: logxfer(desc, byte_count, name, NULL, tdp, error); (*closefunc)(fout); cleanupstore: ; } static FILE * getdatasock(const char *fmode) { int on, s, t, tries; in_port_t port; on = 1; if (data >= 0) return (fdopen(data, fmode)); if (! dropprivs) (void) seteuid((uid_t)0); s = socket(ctrl_addr.su_family, SOCK_STREAM, 0); if (s < 0) goto bad; if (setsockopt(s, SOL_SOCKET, SO_REUSEADDR, (char *) &on, sizeof(on)) < 0) goto bad; if (setsockopt(s, SOL_SOCKET, SO_KEEPALIVE, (char *) &on, sizeof(on)) < 0) goto bad; /* anchor socket to avoid multi-homing problems */ data_source = ctrl_addr; /* * By default source port for PORT connctions is * ctrlport-1 (see RFC959 section 5.2). * However, if privs have been dropped and that * would be < IPPORT_RESERVED, use a random port * instead. */ if (dataport) port = dataport; else port = ntohs(ctrl_addr.su_port) - 1; if (dropprivs && port < IPPORT_RESERVED) port = 0; /* use random port */ data_source.su_port = htons(port); for (tries = 1; ; tries++) { if (bind(s, (struct sockaddr *)&data_source.si_su, data_source.su_len) >= 0) break; if (errno != EADDRINUSE || tries > 10) goto bad; sleep(tries); } if (! dropprivs) (void) seteuid((uid_t)pw->pw_uid); #ifdef IP_TOS if (!mapped && ctrl_addr.su_family == AF_INET) { on = IPTOS_THROUGHPUT; if (setsockopt(s, IPPROTO_IP, IP_TOS, (char *)&on, sizeof(int)) < 0) syslog(LOG_WARNING, "setsockopt (IP_TOS): %m"); } #endif return (fdopen(s, fmode)); bad: /* Return the real value of errno (close may change it) */ t = errno; if (! dropprivs) (void) seteuid((uid_t)pw->pw_uid); (void) close(s); errno = t; return (NULL); } FILE * dataconn(const char *name, off_t size, const char *fmode) { char sizebuf[32]; FILE *file; int retry, tos, keepalive, conerrno; file_size = size; byte_count = 0; if (size != (off_t) -1) (void)snprintf(sizebuf, sizeof(sizebuf), " (" LLF " byte%s)", (LLT)size, PLURAL(size)); else sizebuf[0] = '\0'; if (pdata >= 0) { struct sockinet from; int s; socklen_t fromlen = sizeof(from.su_len); (void) alarm(curclass.timeout); s = accept(pdata, (struct sockaddr *)&from.si_su, &fromlen); (void) alarm(0); if (s < 0) { reply(425, "Can't open data connection."); (void) close(pdata); pdata = -1; return (NULL); } (void) close(pdata); pdata = s; switch (from.su_family) { case AF_INET: #ifdef IP_TOS if (!mapped) { tos = IPTOS_THROUGHPUT; (void) setsockopt(s, IPPROTO_IP, IP_TOS, (char *)&tos, sizeof(int)); } break; #endif } /* Set keepalives on the socket to detect dropped conns. */ #ifdef SO_KEEPALIVE keepalive = 1; (void) setsockopt(s, SOL_SOCKET, SO_KEEPALIVE, (char *)&keepalive, sizeof(int)); #endif reply(150, "Opening %s mode data connection for '%s'%s.", type == TYPE_A ? "ASCII" : "BINARY", name, sizebuf); return (fdopen(pdata, fmode)); } if (data >= 0) { reply(125, "Using existing data connection for '%s'%s.", name, sizebuf); usedefault = 1; return (fdopen(data, fmode)); } if (usedefault) data_dest = his_addr; usedefault = 1; retry = conerrno = 0; do { file = getdatasock(fmode); if (file == NULL) { char hbuf[NI_MAXHOST]; char pbuf[NI_MAXSERV]; if (getnameinfo((struct sockaddr *)&data_source.si_su, data_source.su_len, hbuf, sizeof(hbuf), pbuf, sizeof(pbuf), NI_NUMERICHOST | NI_NUMERICSERV)) strlcpy(hbuf, "?", sizeof(hbuf)); reply(425, "Can't create data socket (%s,%s): %s.", hbuf, pbuf, strerror(errno)); return (NULL); } data = fileno(file); conerrno = 0; if (connect(data, (struct sockaddr *)&data_dest.si_su, data_dest.su_len) == 0) break; conerrno = errno; (void) fclose(file); file = NULL; data = -1; if (conerrno == EADDRINUSE) { sleep((unsigned) swaitint); retry += swaitint; } else { break; } } while (retry <= swaitmax); if (conerrno != 0) { perror_reply(425, "Can't build data connection"); return (NULL); } reply(150, "Opening %s mode data connection for '%s'%s.", type == TYPE_A ? "ASCII" : "BINARY", name, sizebuf); return (file); } void closedataconn(FILE *fd) { if (fd == NULL) return; (void)fclose(fd); data = -1; if (pdata >= 0) (void)close(pdata); pdata = -1; } int write_data(int fd, char *buf, size_t size, off_t *bufrem, struct timeval *then, int isdata) { struct timeval now, td; ssize_t c; while (size > 0) { c = size; if (curclass.writesize) { if (curclass.writesize < c) c = curclass.writesize; } if (curclass.rateget) { if (*bufrem < c) c = *bufrem; } (void) alarm(curclass.timeout); c = write(fd, buf, c); if (c <= 0) return (1); buf += c; size -= c; byte_count += c; if (isdata) { total_data_out += c; total_data += c; } total_bytes_out += c; total_bytes += c; if (curclass.rateget) { *bufrem -= c; if (*bufrem == 0) { (void)gettimeofday(&now, NULL); timersub(&now, then, &td); if (td.tv_sec == 0) { usleep(1000000 - td.tv_usec); (void)gettimeofday(then, NULL); } else *then = now; *bufrem = curclass.rateget; } } } return (0); } static enum send_status send_data_with_read(int filefd, int netfd, const struct stat *st, int isdata) { struct timeval then; off_t bufrem; size_t readsize; char *buf; int c, error; if (curclass.readsize) readsize = curclass.readsize; else readsize = (size_t)st->st_blksize; if ((buf = malloc(readsize)) == NULL) { perror_reply(451, "Local resource failure: malloc"); return (SS_NO_TRANSFER); } if (curclass.rateget) { bufrem = curclass.rateget; (void)gettimeofday(&then, NULL); } while (1) { (void) alarm(curclass.timeout); c = read(filefd, buf, readsize); if (c == 0) error = SS_SUCCESS; else if (c < 0) error = SS_FILE_ERROR; else if (write_data(netfd, buf, c, &bufrem, &then, isdata)) error = SS_DATA_ERROR; else if (urgflag && handleoobcmd()) error = SS_ABORTED; else continue; free(buf); return (error); } } static enum send_status send_data_with_mmap(int filefd, int netfd, const struct stat *st, int isdata) { struct timeval then; off_t bufrem, filesize, off, origoff; size_t mapsize, winsize; int error, sendbufsize, sendlowat; void *win; if (curclass.sendbufsize) { sendbufsize = curclass.sendbufsize; if (setsockopt(netfd, SOL_SOCKET, SO_SNDBUF, &sendbufsize, sizeof(int)) == -1) syslog(LOG_WARNING, "setsockopt(SO_SNDBUF, %d): %m", sendbufsize); } if (curclass.sendlowat) { sendlowat = curclass.sendlowat; if (setsockopt(netfd, SOL_SOCKET, SO_SNDLOWAT, &sendlowat, sizeof(int)) == -1) syslog(LOG_WARNING, "setsockopt(SO_SNDLOWAT, %d): %m", sendlowat); } winsize = curclass.mmapsize; filesize = st->st_size; if (ftpd_debug) syslog(LOG_INFO, "mmapsize = %ld, writesize = %ld", (long)winsize, (long)curclass.writesize); if (winsize == 0) goto try_read; off = lseek(filefd, (off_t)0, SEEK_CUR); if (off == -1) goto try_read; origoff = off; if (curclass.rateget) { bufrem = curclass.rateget; (void)gettimeofday(&then, NULL); } while (1) { mapsize = MIN(filesize - off, winsize); if (mapsize == 0) break; win = mmap(NULL, mapsize, PROT_READ, MAP_FILE|MAP_SHARED, filefd, off); if (win == MAP_FAILED) { if (off == origoff) goto try_read; return (SS_FILE_ERROR); } (void) madvise(win, mapsize, MADV_SEQUENTIAL); error = write_data(netfd, win, mapsize, &bufrem, &then, isdata); (void) madvise(win, mapsize, MADV_DONTNEED); munmap(win, mapsize); if (urgflag && handleoobcmd()) return (SS_ABORTED); if (error) return (SS_DATA_ERROR); off += mapsize; } return (SS_SUCCESS); try_read: return (send_data_with_read(filefd, netfd, st, isdata)); } /* * Tranfer the contents of "instr" to "outstr" peer using the appropriate * encapsulation of the data subject to Mode, Structure, and Type. * * NB: Form isn't handled. */ static int send_data(FILE *instr, FILE *outstr, const struct stat *st, int isdata) { int c, filefd, netfd, rval; urgflag = 0; transflag = 1; rval = -1; switch (type) { case TYPE_A: /* XXXLUKEM: rate limit ascii send (get) */ (void) alarm(curclass.timeout); while ((c = getc(instr)) != EOF) { if (urgflag && handleoobcmd()) goto cleanup_send_data; byte_count++; if (c == '\n') { if (ferror(outstr)) goto data_err; (void) putc('\r', outstr); if (isdata) { total_data_out++; total_data++; } total_bytes_out++; total_bytes++; } (void) putc(c, outstr); if (isdata) { total_data_out++; total_data++; } total_bytes_out++; total_bytes++; if ((byte_count % 4096) == 0) (void) alarm(curclass.timeout); } (void) alarm(0); fflush(outstr); if (ferror(instr)) goto file_err; if (ferror(outstr)) goto data_err; rval = 0; goto cleanup_send_data; case TYPE_I: case TYPE_L: filefd = fileno(instr); netfd = fileno(outstr); switch (send_data_with_mmap(filefd, netfd, st, isdata)) { case SS_SUCCESS: break; case SS_ABORTED: case SS_NO_TRANSFER: goto cleanup_send_data; case SS_FILE_ERROR: goto file_err; case SS_DATA_ERROR: goto data_err; } rval = 0; goto cleanup_send_data; default: reply(550, "Unimplemented TYPE %d in send_data", type); goto cleanup_send_data; } data_err: (void) alarm(0); perror_reply(426, "Data connection"); goto cleanup_send_data; file_err: (void) alarm(0); perror_reply(551, "Error on input file"); goto cleanup_send_data; cleanup_send_data: (void) alarm(0); transflag = 0; urgflag = 0; if (isdata) { total_files_out++; total_files++; } total_xfers_out++; total_xfers++; return (rval); } /* * Transfer data from peer to "outstr" using the appropriate encapulation of * the data subject to Mode, Structure, and Type. * * N.B.: Form isn't handled. */ static int receive_data(FILE *instr, FILE *outstr) { int c, netfd, filefd, rval; int volatile bare_lfs; off_t byteswritten; char *buf; size_t readsize; struct sigaction sa, sa_saved; struct stat st; memset(&sa, 0, sizeof(sa)); sigfillset(&sa.sa_mask); sa.sa_flags = SA_RESTART; sa.sa_handler = lostconn; (void) sigaction(SIGALRM, &sa, &sa_saved); bare_lfs = 0; urgflag = 0; transflag = 1; rval = -1; byteswritten = 0; buf = NULL; #define FILESIZECHECK(x) \ do { \ if (curclass.maxfilesize != -1 && \ (x) > curclass.maxfilesize) { \ errno = EFBIG; \ goto file_err; \ } \ } while (0) switch (type) { case TYPE_I: case TYPE_L: netfd = fileno(instr); filefd = fileno(outstr); (void) alarm(curclass.timeout); if (curclass.readsize) readsize = curclass.readsize; else if (fstat(filefd, &st)) readsize = (size_t)st.st_blksize; else readsize = BUFSIZ; if ((buf = malloc(readsize)) == NULL) { perror_reply(451, "Local resource failure: malloc"); goto cleanup_recv_data; } if (curclass.rateput) { while (1) { int d; struct timeval then, now, td; off_t bufrem; (void)gettimeofday(&then, NULL); errno = c = d = 0; for (bufrem = curclass.rateput; bufrem > 0; ) { if ((c = read(netfd, buf, MIN(readsize, bufrem))) <= 0) goto recvdone; if (urgflag && handleoobcmd()) goto cleanup_recv_data; FILESIZECHECK(byte_count + c); if ((d = write(filefd, buf, c)) != c) goto file_err; (void) alarm(curclass.timeout); bufrem -= c; byte_count += c; total_data_in += c; total_data += c; total_bytes_in += c; total_bytes += c; } (void)gettimeofday(&now, NULL); timersub(&now, &then, &td); if (td.tv_sec == 0) usleep(1000000 - td.tv_usec); } } else { while ((c = read(netfd, buf, readsize)) > 0) { if (urgflag && handleoobcmd()) goto cleanup_recv_data; FILESIZECHECK(byte_count + c); if (write(filefd, buf, c) != c) goto file_err; (void) alarm(curclass.timeout); byte_count += c; total_data_in += c; total_data += c; total_bytes_in += c; total_bytes += c; } } recvdone: if (c < 0) goto data_err; rval = 0; goto cleanup_recv_data; case TYPE_E: reply(553, "TYPE E not implemented."); goto cleanup_recv_data; case TYPE_A: (void) alarm(curclass.timeout); /* XXXLUKEM: rate limit ascii receive (put) */ while ((c = getc(instr)) != EOF) { if (urgflag && handleoobcmd()) goto cleanup_recv_data; byte_count++; total_data_in++; total_data++; total_bytes_in++; total_bytes++; if ((byte_count % 4096) == 0) (void) alarm(curclass.timeout); if (c == '\n') bare_lfs++; while (c == '\r') { if (ferror(outstr)) goto data_err; if ((c = getc(instr)) != '\n') { byte_count++; total_data_in++; total_data++; total_bytes_in++; total_bytes++; if ((byte_count % 4096) == 0) (void) alarm(curclass.timeout); byteswritten++; FILESIZECHECK(byteswritten); (void) putc ('\r', outstr); if (c == '\0' || c == EOF) goto contin2; } } byteswritten++; FILESIZECHECK(byteswritten); (void) putc(c, outstr); contin2: ; } (void) alarm(0); fflush(outstr); if (ferror(instr)) goto data_err; if (ferror(outstr)) goto file_err; if (bare_lfs) { reply(-226, "WARNING! %d bare linefeeds received in ASCII mode", bare_lfs); reply(0, "File may not have transferred correctly."); } rval = 0; goto cleanup_recv_data; default: reply(550, "Unimplemented TYPE %d in receive_data", type); goto cleanup_recv_data; } #undef FILESIZECHECK data_err: (void) alarm(0); perror_reply(426, "Data Connection"); goto cleanup_recv_data; file_err: (void) alarm(0); perror_reply(452, "Error writing file"); goto cleanup_recv_data; cleanup_recv_data: (void) alarm(0); (void) sigaction(SIGALRM, &sa_saved, NULL); if (buf) free(buf); transflag = 0; urgflag = 0; total_files_in++; total_files++; total_xfers_in++; total_xfers++; return (rval); } void statcmd(void) { struct sockinet *su = NULL; static char hbuf[NI_MAXHOST], sbuf[NI_MAXSERV]; u_char *a, *p; int ispassive, af; off_t otbi, otbo, otb; a = p = (u_char *)NULL; reply(-211, "%s FTP server status:", hostname); reply(0, "Version: %s", EMPTYSTR(version) ? "" : version); hbuf[0] = '\0'; if (!getnameinfo((struct sockaddr *)&his_addr.si_su, his_addr.su_len, hbuf, sizeof(hbuf), NULL, 0, NI_NUMERICHOST) && strcmp(remotehost, hbuf) != 0) reply(0, "Connected to %s (%s)", remotehost, hbuf); else reply(0, "Connected to %s", remotehost); if (logged_in) { if (curclass.type == CLASS_GUEST) reply(0, "Logged in anonymously"); else reply(0, "Logged in as %s%s", pw->pw_name, curclass.type == CLASS_CHROOT ? " (chroot)" : ""); } else if (askpasswd) reply(0, "Waiting for password"); else reply(0, "Waiting for user name"); cprintf(stdout, " TYPE: %s", typenames[type]); if (type == TYPE_A || type == TYPE_E) cprintf(stdout, ", FORM: %s", formnames[form]); if (type == TYPE_L) { #if NBBY == 8 cprintf(stdout, " %d", NBBY); #else /* XXX: `bytesize' needs to be defined in this case */ cprintf(stdout, " %d", bytesize); #endif } cprintf(stdout, "; STRUcture: %s; transfer MODE: %s\r\n", strunames[stru], modenames[mode]); ispassive = 0; if (data != -1) { reply(0, "Data connection open"); su = NULL; } else if (pdata != -1) { reply(0, "in Passive mode"); if (curclass.advertise.su_len != 0) su = &curclass.advertise; else su = &pasv_addr; ispassive = 1; goto printaddr; } else if (usedefault == 0) { su = (struct sockinet *)&data_dest; if (epsvall) { reply(0, "EPSV only mode (EPSV ALL)"); goto epsvonly; } printaddr: /* PASV/PORT */ if (su->su_family == AF_INET) { a = (u_char *) &su->su_addr; p = (u_char *) &su->su_port; #define UC(b) (((int) b) & 0xff) reply(0, "%s (%d,%d,%d,%d,%d,%d)", ispassive ? "PASV" : "PORT" , UC(a[0]), UC(a[1]), UC(a[2]), UC(a[3]), UC(p[0]), UC(p[1])); } /* LPSV/LPRT */ { int alen, i; alen = 0; switch (su->su_family) { case AF_INET: a = (u_char *) &su->su_addr; p = (u_char *) &su->su_port; alen = sizeof(su->su_addr); af = 4; break; #ifdef INET6 case AF_INET6: a = (u_char *) &su->su_6addr; p = (u_char *) &su->su_port; alen = sizeof(su->su_6addr); af = 6; break; #endif default: af = 0; break; } if (af) { cprintf(stdout, " %s (%d,%d", ispassive ? "LPSV" : "LPRT", af, alen); for (i = 0; i < alen; i++) cprintf(stdout, ",%d", UC(a[i])); cprintf(stdout, ",%d,%d,%d)\r\n", 2, UC(p[0]), UC(p[1])); #undef UC } } /* EPRT/EPSV */ epsvonly: af = af2epsvproto(su->su_family); hbuf[0] = '\0'; if (af > 0) { struct sockinet tmp; tmp = *su; #ifdef INET6 if (tmp.su_family == AF_INET6) tmp.su_scope_id = 0; #endif if (getnameinfo((struct sockaddr *)&tmp.si_su, tmp.su_len, hbuf, sizeof(hbuf), sbuf, sizeof(sbuf), NI_NUMERICHOST | NI_NUMERICSERV) == 0) reply(0, "%s (|%d|%s|%s|)", ispassive ? "EPSV" : "EPRT", af, hbuf, sbuf); } } else reply(0, "No data connection"); if (logged_in) { reply(0, "Data sent: " LLF " byte%s in " LLF " file%s", (LLT)total_data_out, PLURAL(total_data_out), (LLT)total_files_out, PLURAL(total_files_out)); reply(0, "Data received: " LLF " byte%s in " LLF " file%s", (LLT)total_data_in, PLURAL(total_data_in), (LLT)total_files_in, PLURAL(total_files_in)); reply(0, "Total data: " LLF " byte%s in " LLF " file%s", (LLT)total_data, PLURAL(total_data), (LLT)total_files, PLURAL(total_files)); } otbi = total_bytes_in; otbo = total_bytes_out; otb = total_bytes; reply(0, "Traffic sent: " LLF " byte%s in " LLF " transfer%s", (LLT)otbo, PLURAL(otbo), (LLT)total_xfers_out, PLURAL(total_xfers_out)); reply(0, "Traffic received: " LLF " byte%s in " LLF " transfer%s", (LLT)otbi, PLURAL(otbi), (LLT)total_xfers_in, PLURAL(total_xfers_in)); reply(0, "Total traffic: " LLF " byte%s in " LLF " transfer%s", (LLT)otb, PLURAL(otb), (LLT)total_xfers, PLURAL(total_xfers)); if (logged_in && !CURCLASS_FLAGS_ISSET(private)) { struct ftpconv *cp; reply(0, "%s", ""); reply(0, "Class: %s, type: %s", curclass.classname, CURCLASSTYPE); reply(0, "Check PORT/LPRT commands: %sabled", CURCLASS_FLAGS_ISSET(checkportcmd) ? "en" : "dis"); if (! EMPTYSTR(curclass.display)) reply(0, "Display file: %s", curclass.display); if (! EMPTYSTR(curclass.notify)) reply(0, "Notify fileglob: %s", curclass.notify); reply(0, "Idle timeout: " LLF ", maximum timeout: " LLF, (LLT)curclass.timeout, (LLT)curclass.maxtimeout); reply(0, "Current connections: %d", connections); if (curclass.limit == -1) reply(0, "Maximum connections: unlimited"); else reply(0, "Maximum connections: " LLF, (LLT)curclass.limit); if (curclass.limitfile) reply(0, "Connection limit exceeded message file: %s", conffilename(curclass.limitfile)); if (! EMPTYSTR(curclass.chroot)) reply(0, "Chroot format: %s", curclass.chroot); reply(0, "Deny bad ftpusers(5) quickly: %sabled", CURCLASS_FLAGS_ISSET(denyquick) ? "en" : "dis"); if (! EMPTYSTR(curclass.homedir)) reply(0, "Homedir format: %s", curclass.homedir); if (curclass.maxfilesize == -1) reply(0, "Maximum file size: unlimited"); else reply(0, "Maximum file size: " LLF, (LLT)curclass.maxfilesize); if (! EMPTYSTR(curclass.motd)) reply(0, "MotD file: %s", conffilename(curclass.motd)); reply(0, "Modify commands (CHMOD, DELE, MKD, RMD, RNFR, UMASK): %sabled", CURCLASS_FLAGS_ISSET(modify) ? "en" : "dis"); reply(0, "Upload commands (APPE, STOR, STOU): %sabled", CURCLASS_FLAGS_ISSET(upload) ? "en" : "dis"); reply(0, "Sanitize file names: %sabled", CURCLASS_FLAGS_ISSET(sanenames) ? "en" : "dis"); reply(0, "PASV/LPSV/EPSV connections: %sabled", CURCLASS_FLAGS_ISSET(passive) ? "en" : "dis"); if (curclass.advertise.su_len != 0) { char buf[50]; /* big enough for IPv6 address */ const char *bp; bp = inet_ntop(curclass.advertise.su_family, (void *)&curclass.advertise.su_addr, buf, sizeof(buf)); if (bp != NULL) reply(0, "PASV advertise address: %s", bp); } if (curclass.portmin && curclass.portmax) reply(0, "PASV port range: " LLF " - " LLF, (LLT)curclass.portmin, (LLT)curclass.portmax); if (curclass.rateget) reply(0, "Rate get limit: " LLF " bytes/sec", (LLT)curclass.rateget); else reply(0, "Rate get limit: disabled"); if (curclass.rateput) reply(0, "Rate put limit: " LLF " bytes/sec", (LLT)curclass.rateput); else reply(0, "Rate put limit: disabled"); if (curclass.mmapsize) reply(0, "Mmap size: " LLF, (LLT)curclass.mmapsize); else reply(0, "Mmap size: disabled"); if (curclass.readsize) reply(0, "Read size: " LLF, (LLT)curclass.readsize); else reply(0, "Read size: default"); if (curclass.writesize) reply(0, "Write size: " LLF, (LLT)curclass.writesize); else reply(0, "Write size: default"); if (curclass.recvbufsize) reply(0, "Receive buffer size: " LLF, (LLT)curclass.recvbufsize); else reply(0, "Receive buffer size: default"); if (curclass.sendbufsize) reply(0, "Send buffer size: " LLF, (LLT)curclass.sendbufsize); else reply(0, "Send buffer size: default"); if (curclass.sendlowat) reply(0, "Send low water mark: " LLF, (LLT)curclass.sendlowat); else reply(0, "Send low water mark: default"); reply(0, "Umask: %.04o", curclass.umask); for (cp = curclass.conversions; cp != NULL; cp=cp->next) { if (cp->suffix == NULL || cp->types == NULL || cp->command == NULL) continue; reply(0, "Conversion: %s [%s] disable: %s, command: %s", cp->suffix, cp->types, cp->disable, cp->command); } } reply(211, "End of status"); } void fatal(const char *s) { reply(451, "Error in server: %s\n", s); reply(221, "Closing connection due to server error."); dologout(0); /* NOTREACHED */ } /* * reply() -- * depending on the value of n, display fmt with a trailing CRLF and * prefix of: * n < -1 prefix the message with abs(n) + "-" (initial line) * n == 0 prefix the message with 4 spaces (middle lines) * n > 0 prefix the message with n + " " (final line) */ void reply(int n, const char *fmt, ...) { char msg[MAXPATHLEN * 2 + 100]; size_t b; va_list ap; b = 0; if (n == 0) b = snprintf(msg, sizeof(msg), " "); else if (n < 0) b = snprintf(msg, sizeof(msg), "%d-", -n); else b = snprintf(msg, sizeof(msg), "%d ", n); va_start(ap, fmt); vsnprintf(msg + b, sizeof(msg) - b, fmt, ap); va_end(ap); cprintf(stdout, "%s\r\n", msg); (void)fflush(stdout); if (ftpd_debug) syslog(LOG_DEBUG, "<--- %s", msg); } static void logremotehost(struct sockinet *who) { if (getnameinfo((struct sockaddr *)&who->si_su, who->su_len, remotehost, sizeof(remotehost), NULL, 0, getnameopts)) strlcpy(remotehost, "?", sizeof(remotehost)); #if defined(HAVE_SETPROCTITLE) snprintf(proctitle, sizeof(proctitle), "%s: connected", remotehost); setproctitle("%s", proctitle); #endif /* defined(HAVE_SETPROCTITLE) */ if (logging) syslog(LOG_INFO, "connection from %s to %s", remotehost, hostname); } /* * Record logout in wtmp file and exit with supplied status. * NOTE: because this is called from signal handlers it cannot * use stdio (or call other functions that use stdio). */ void dologout(int status) { /* * Prevent reception of SIGURG from resulting in a resumption * back to the main program loop. */ transflag = 0; logout_utmp(); if (logged_in) { #ifdef KERBEROS if (!notickets && krbtkfile_env) unlink(krbtkfile_env); #endif } /* beware of flushing buffers after a SIGPIPE */ if (xferlogfd != -1) close(xferlogfd); _exit(status); } void abor(void) { if (!transflag) return; tmpline[0] = '\0'; is_oob = 0; reply(426, "Transfer aborted. Data connection closed."); reply(226, "Abort successful"); transflag = 0; /* flag that the transfer has aborted */ } void statxfer(void) { if (!transflag) return; tmpline[0] = '\0'; is_oob = 0; if (file_size != (off_t) -1) reply(213, "Status: " LLF " of " LLF " byte%s transferred", (LLT)byte_count, (LLT)file_size, PLURAL(byte_count)); else reply(213, "Status: " LLF " byte%s transferred", (LLT)byte_count, PLURAL(byte_count)); } /* * Call when urgflag != 0 to handle Out Of Band commands. * Returns non zero if the OOB command aborted the transfer * by setting transflag to 0. (c.f., "ABOR"). */ static int handleoobcmd() { char *cp; if (!urgflag) return (0); urgflag = 0; /* only process if transfer occurring */ if (!transflag) return (0); cp = tmpline; if (getline(cp, sizeof(tmpline), stdin) == NULL) { reply(221, "You could at least say goodbye."); dologout(0); } /* * Manually parse OOB commands, because we can't * recursively call the yacc parser... */ if (strcasecmp(cp, "ABOR\r\n") == 0) { abor(); } else if (strcasecmp(cp, "STAT\r\n") == 0) { statxfer(); } else { /* XXX: error with "500 unknown command" ? */ } return (transflag == 0); } static int bind_pasv_addr(void) { static int passiveport; int port, len; len = pasv_addr.su_len; if (curclass.portmin == 0 && curclass.portmax == 0) { pasv_addr.su_port = 0; return (bind(pdata, (struct sockaddr *)&pasv_addr.si_su, len)); } if (passiveport == 0) { srand(getpid()); passiveport = rand() % (curclass.portmax - curclass.portmin) + curclass.portmin; } port = passiveport; while (1) { port++; if (port > curclass.portmax) port = curclass.portmin; else if (port == passiveport) { errno = EAGAIN; return (-1); } pasv_addr.su_port = htons(port); if (bind(pdata, (struct sockaddr *)&pasv_addr.si_su, len) == 0) break; if (errno != EADDRINUSE) return (-1); } passiveport = port; return (0); } /* * Note: a response of 425 is not mentioned as a possible response to * the PASV command in RFC959. However, it has been blessed as * a legitimate response by Jon Postel in a telephone conversation * with Rick Adams on 25 Jan 89. */ void passive(void) { socklen_t len, recvbufsize; char *p, *a; if (pdata >= 0) close(pdata); pdata = socket(AF_INET, SOCK_STREAM, 0); if (pdata < 0 || !logged_in) { perror_reply(425, "Can't open passive connection"); return; } pasv_addr = ctrl_addr; if (bind_pasv_addr() < 0) goto pasv_error; len = pasv_addr.su_len; if (getsockname(pdata, (struct sockaddr *) &pasv_addr.si_su, &len) < 0) goto pasv_error; pasv_addr.su_len = len; if (curclass.recvbufsize) { recvbufsize = curclass.recvbufsize; if (setsockopt(pdata, SOL_SOCKET, SO_RCVBUF, &recvbufsize, sizeof(int)) == -1) syslog(LOG_WARNING, "setsockopt(SO_RCVBUF, %d): %m", recvbufsize); } if (listen(pdata, 1) < 0) goto pasv_error; if (curclass.advertise.su_len != 0) a = (char *) &curclass.advertise.su_addr; else a = (char *) &pasv_addr.su_addr; p = (char *) &pasv_addr.su_port; #define UC(b) (((int) b) & 0xff) reply(227, "Entering Passive Mode (%d,%d,%d,%d,%d,%d)", UC(a[0]), UC(a[1]), UC(a[2]), UC(a[3]), UC(p[0]), UC(p[1])); return; pasv_error: (void) close(pdata); pdata = -1; perror_reply(425, "Can't open passive connection"); return; } /* * convert protocol identifier to/from AF */ int lpsvproto2af(int proto) { switch (proto) { case 4: return AF_INET; #ifdef INET6 case 6: return AF_INET6; #endif default: return -1; } } int af2lpsvproto(int af) { switch (af) { case AF_INET: return 4; #ifdef INET6 case AF_INET6: return 6; #endif default: return -1; } } int epsvproto2af(int proto) { switch (proto) { case 1: return AF_INET; #ifdef INET6 case 2: return AF_INET6; #endif default: return -1; } } int af2epsvproto(int af) { switch (af) { case AF_INET: return 1; #ifdef INET6 case AF_INET6: return 2; #endif default: return -1; } } /* * 228 Entering Long Passive Mode (af, hal, h1, h2, h3,..., pal, p1, p2...) * 229 Entering Extended Passive Mode (|||port|) */ void long_passive(char *cmd, int pf) { socklen_t len; char *p, *a; if (!logged_in) { syslog(LOG_NOTICE, "long passive but not logged in"); reply(503, "Login with USER first."); return; } if (pf != PF_UNSPEC && ctrl_addr.su_family != pf) { /* * XXX: only EPRT/EPSV ready clients will understand this */ if (strcmp(cmd, "EPSV") != 0) reply(501, "Network protocol mismatch"); /*XXX*/ else epsv_protounsupp("Network protocol mismatch"); return; } if (pdata >= 0) close(pdata); pdata = socket(ctrl_addr.su_family, SOCK_STREAM, 0); if (pdata < 0) { perror_reply(425, "Can't open passive connection"); return; } pasv_addr = ctrl_addr; if (bind_pasv_addr() < 0) goto pasv_error; len = pasv_addr.su_len; if (getsockname(pdata, (struct sockaddr *) &pasv_addr.si_su, &len) < 0) goto pasv_error; pasv_addr.su_len = len; if (listen(pdata, 1) < 0) goto pasv_error; p = (char *) &pasv_addr.su_port; #define UC(b) (((int) b) & 0xff) if (strcmp(cmd, "LPSV") == 0) { struct sockinet *advert; if (curclass.advertise.su_len != 0) advert = &curclass.advertise; else advert = &pasv_addr; switch (advert->su_family) { case AF_INET: a = (char *) &advert->su_addr; reply(228, "Entering Long Passive Mode (%d,%d,%d,%d,%d,%d,%d,%d,%d)", 4, 4, UC(a[0]), UC(a[1]), UC(a[2]), UC(a[3]), 2, UC(p[0]), UC(p[1])); return; #ifdef INET6 case AF_INET6: a = (char *) &advert->su_6addr; reply(228, "Entering Long Passive Mode (%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d)", 6, 16, UC(a[0]), UC(a[1]), UC(a[2]), UC(a[3]), UC(a[4]), UC(a[5]), UC(a[6]), UC(a[7]), UC(a[8]), UC(a[9]), UC(a[10]), UC(a[11]), UC(a[12]), UC(a[13]), UC(a[14]), UC(a[15]), 2, UC(p[0]), UC(p[1])); return; #endif } #undef UC } else if (strcmp(cmd, "EPSV") == 0) { switch (pasv_addr.su_family) { case AF_INET: #ifdef INET6 case AF_INET6: #endif reply(229, "Entering Extended Passive Mode (|||%d|)", ntohs(pasv_addr.su_port)); return; } } else { /* more proper error code? */ } pasv_error: (void) close(pdata); pdata = -1; perror_reply(425, "Can't open passive connection"); return; } int extended_port(const char *arg) { char *tmp = NULL; char *result[3]; char *p, *q; char delim; struct addrinfo hints; struct addrinfo *res = NULL; int i; unsigned long proto; tmp = ftpd_strdup(arg); p = tmp; delim = p[0]; p++; memset(result, 0, sizeof(result)); for (i = 0; i < 3; i++) { q = strchr(p, delim); if (!q || *q != delim) goto parsefail; *q++ = '\0'; result[i] = p; p = q; } /* some more sanity checks */ errno = 0; p = NULL; (void)strtoul(result[2], &p, 10); if (errno || !*result[2] || *p) goto parsefail; errno = 0; p = NULL; proto = strtoul(result[0], &p, 10); if (errno || !*result[0] || *p) goto protounsupp; memset(&hints, 0, sizeof(hints)); hints.ai_family = epsvproto2af((int)proto); if (hints.ai_family < 0) goto protounsupp; hints.ai_socktype = SOCK_STREAM; hints.ai_flags = AI_NUMERICHOST; if (getaddrinfo(result[1], result[2], &hints, &res)) goto parsefail; if (res->ai_next) goto parsefail; if (sizeof(data_dest) < res->ai_addrlen) goto parsefail; memcpy(&data_dest.si_su, res->ai_addr, res->ai_addrlen); data_dest.su_len = res->ai_addrlen; #ifdef INET6 if (his_addr.su_family == AF_INET6 && data_dest.su_family == AF_INET6) { /* XXX: more sanity checks! */ data_dest.su_scope_id = his_addr.su_scope_id; } #endif if (tmp != NULL) free(tmp); if (res) freeaddrinfo(res); return 0; parsefail: reply(500, "Invalid argument, rejected."); usedefault = 1; if (tmp != NULL) free(tmp); if (res) freeaddrinfo(res); return -1; protounsupp: epsv_protounsupp("Protocol not supported"); usedefault = 1; if (tmp != NULL) free(tmp); return -1; } /* * 522 Protocol not supported (proto,...) * as we assume address family for control and data connections are the same, * we do not return the list of address families we support - instead, we * return the address family of the control connection. */ void epsv_protounsupp(const char *message) { int proto; proto = af2epsvproto(ctrl_addr.su_family); if (proto < 0) reply(501, "%s", message); /* XXX */ else reply(522, "%s, use (%d)", message, proto); } /* * Generate unique name for file with basename "local". * The file named "local" is already known to exist. * Generates failure reply on error. * * XXX: this function should under go changes similar to * the mktemp(3)/mkstemp(3) changes. */ static char * gunique(const char *local) { static char new[MAXPATHLEN]; struct stat st; char *cp; int count; cp = strrchr(local, '/'); if (cp) *cp = '\0'; if (stat(cp ? local : ".", &st) < 0) { perror_reply(553, cp ? local : "."); return (NULL); } if (cp) *cp = '/'; for (count = 1; count < 100; count++) { (void)snprintf(new, sizeof(new) - 1, "%s.%d", local, count); if (stat(new, &st) < 0) return (new); } reply(452, "Unique file name cannot be created."); return (NULL); } /* * Format and send reply containing system error number. */ void perror_reply(int code, const char *string) { int save_errno; save_errno = errno; reply(code, "%s: %s.", string, strerror(errno)); errno = save_errno; } static char *onefile[] = { "", 0 }; void send_file_list(const char *whichf) { struct stat st; DIR *dirp; struct dirent *dir; FILE *volatile dout; char **volatile dirlist; char *dirname, *p; char *notglob; int volatile simple; int volatile freeglob; glob_t gl; dirp = NULL; dout = NULL; notglob = NULL; simple = 0; freeglob = 0; urgflag = 0; p = NULL; if (strpbrk(whichf, "~{[*?") != NULL) { int flags = GLOB_BRACE|GLOB_NOCHECK|GLOB_TILDE|GLOB_LIMIT; memset(&gl, 0, sizeof(gl)); freeglob = 1; if (glob(whichf, flags, 0, &gl)) { reply(450, "Not found"); goto cleanup_send_file_list; } else if (gl.gl_pathc == 0) { errno = ENOENT; perror_reply(450, whichf); goto cleanup_send_file_list; } dirlist = gl.gl_pathv; } else { notglob = ftpd_strdup(whichf); onefile[0] = notglob; dirlist = onefile; simple = 1; } /* XXX: } for vi sm */ while ((dirname = *dirlist++) != NULL) { int trailingslash = 0; if (stat(dirname, &st) < 0) { /* * If user typed "ls -l", etc, and the client * used NLST, do what the user meant. */ /* XXX: nuke this support? */ if (dirname[0] == '-' && *dirlist == NULL && transflag == 0) { char *argv[] = { INTERNAL_LS, "", NULL }; argv[1] = dirname; retrieve(argv, dirname); goto cleanup_send_file_list; } perror_reply(450, whichf); goto cleanup_send_file_list; } if (S_ISREG(st.st_mode)) { /* * XXXRFC: * should we follow RFC959 and not work * for non directories? */ if (dout == NULL) { dout = dataconn("file list", (off_t)-1, "w"); if (dout == NULL) goto cleanup_send_file_list; transflag = 1; } cprintf(dout, "%s%s\n", dirname, type == TYPE_A ? "\r" : ""); continue; } else if (!S_ISDIR(st.st_mode)) continue; if (dirname[strlen(dirname) - 1] == '/') trailingslash++; if ((dirp = opendir(dirname)) == NULL) continue; while ((dir = readdir(dirp)) != NULL) { char nbuf[MAXPATHLEN]; if (urgflag && handleoobcmd()) goto cleanup_send_file_list; if (ISDOTDIR(dir->d_name) || ISDOTDOTDIR(dir->d_name)) continue; (void)snprintf(nbuf, sizeof(nbuf), "%s%s%s", dirname, trailingslash ? "" : "/", dir->d_name); /* * We have to do a stat to ensure it's * not a directory or special file. */ /* * XXXRFC: * should we follow RFC959 and filter out * non files ? lukem - NO!, or not until * our ftp client uses MLS{T,D} for completion. */ if (simple || (stat(nbuf, &st) == 0 && S_ISREG(st.st_mode))) { if (dout == NULL) { dout = dataconn("file list", (off_t)-1, "w"); if (dout == NULL) goto cleanup_send_file_list; transflag = 1; } p = nbuf; if (nbuf[0] == '.' && nbuf[1] == '/') p = &nbuf[2]; cprintf(dout, "%s%s\n", p, type == TYPE_A ? "\r" : ""); } } (void) closedir(dirp); } if (dout == NULL) reply(450, "No files found."); else if (ferror(dout) != 0) perror_reply(451, "Data connection"); else reply(226, "Transfer complete."); cleanup_send_file_list: closedataconn(dout); transflag = 0; urgflag = 0; total_xfers++; total_xfers_out++; if (notglob) free(notglob); if (freeglob) globfree(&gl); } char * conffilename(const char *s) { static char filename[MAXPATHLEN]; if (*s == '/') strlcpy(filename, s, sizeof(filename)); else (void)snprintf(filename, sizeof(filename), "%s/%s", confdir ,s); return (filename); } /* * logxfer -- * if logging > 1, then based on the arguments, syslog a message: * if bytes != -1 " = bytes" * else if file2 != NULL " " * else " " * if elapsed != NULL, append "in xxx.yyy seconds" * if error != NULL, append ": " + error * * if doxferlog != 0, bytes != -1, and command is "get", "put", * or "append", syslog and/or write a wu-ftpd style xferlog entry */ void logxfer(const char *command, off_t bytes, const char *file1, const char *file2, const struct timeval *elapsed, const char *error) { char buf[MAXPATHLEN * 2 + 100]; char realfile1[MAXPATHLEN], realfile2[MAXPATHLEN]; const char *r1, *r2; char direction; size_t len; time_t now; if (logging <=1 && !doxferlog) return; r1 = r2 = NULL; if ((r1 = realpath(file1, realfile1)) == NULL) r1 = file1; if (file2 != NULL) if ((r2 = realpath(file2, realfile2)) == NULL) r2 = file2; /* * syslog command */ if (logging > 1) { len = snprintf(buf, sizeof(buf), "%s %s", command, r1); if (bytes != (off_t)-1) len += snprintf(buf + len, sizeof(buf) - len, " = " LLF " byte%s", (LLT) bytes, PLURAL(bytes)); else if (r2 != NULL) len += snprintf(buf + len, sizeof(buf) - len, " %s", r2); if (elapsed != NULL) len += snprintf(buf + len, sizeof(buf) - len, " in %ld.%.03d seconds", elapsed->tv_sec, (int)(elapsed->tv_usec / 1000)); if (error != NULL) len += snprintf(buf + len, sizeof(buf) - len, ": %s", error); syslog(LOG_INFO, "%s", buf); } /* * syslog wu-ftpd style log entry, prefixed with "xferlog: " */ if (!doxferlog || bytes == -1) return; if (strcmp(command, "get") == 0) direction = 'o'; else if (strcmp(command, "put") == 0 || strcmp(command, "append") == 0) direction = 'i'; else return; time(&now); len = snprintf(buf, sizeof(buf), "%.24s %ld %s " LLF " %s %c %s %c %c %s FTP 0 * %c\n", /* * XXX: wu-ftpd puts ' (send)' or ' (recv)' in the syslog message, and removes * the full date. This may be problematic for accurate log parsing, * given that syslog messages don't contain the full date. */ ctime(&now), elapsed == NULL ? 0 : elapsed->tv_sec + (elapsed->tv_usec > 0), remotehost, (LLT) bytes, r1, type == TYPE_A ? 'a' : 'b', "_", /* XXX: take conversions into account? */ direction, curclass.type == CLASS_GUEST ? 'a' : curclass.type == CLASS_CHROOT ? 'g' : curclass.type == CLASS_REAL ? 'r' : '?', curclass.type == CLASS_GUEST ? pw->pw_passwd : pw->pw_name, error != NULL ? 'i' : 'c' ); if ((doxferlog & 2) && xferlogfd != -1) write(xferlogfd, buf, len); if ((doxferlog & 1)) { buf[len-1] = '\n'; /* strip \n from syslog message */ syslog(LOG_INFO, "xferlog: %s", buf); } } /* * Log the resource usage. * * XXX: more resource usage to logging? */ void logrusage(const struct rusage *rusage_before, const struct rusage *rusage_after) { struct timeval usrtime, systime; if (logging <= 1) return; timersub(&rusage_after->ru_utime, &rusage_before->ru_utime, &usrtime); timersub(&rusage_after->ru_stime, &rusage_before->ru_stime, &systime); syslog(LOG_INFO, "%ld.%.03du %ld.%.03ds %ld+%ldio %ldpf+%ldw", usrtime.tv_sec, (int)(usrtime.tv_usec / 1000), systime.tv_sec, (int)(systime.tv_usec / 1000), rusage_after->ru_inblock - rusage_before->ru_inblock, rusage_after->ru_oublock - rusage_before->ru_oublock, rusage_after->ru_majflt - rusage_before->ru_majflt, rusage_after->ru_nswap - rusage_before->ru_nswap); } /* * Determine if `password' is valid for user given in `pw'. * Returns 2 if password expired, 1 if otherwise failed, 0 if ok */ int checkpassword(const struct passwd *pwent, const char *password) { char *orig, *new; time_t change, expire, now; change = expire = 0; if (pwent == NULL) return 1; time(&now); orig = pwent->pw_passwd; /* save existing password */ expire = pwent->pw_expire; change = (pwent->pw_change == _PASSWORD_CHGNOW)? now : pwent->pw_change; if (orig[0] == '\0') /* don't allow empty passwords */ return 1; new = crypt(password, orig); /* encrypt given password */ if (strcmp(new, orig) != 0) /* compare */ return 1; if ((expire && now >= expire) || (change && now >= change)) return 2; /* check if expired */ return 0; /* OK! */ } char * ftpd_strdup(const char *s) { char *new = strdup(s); if (new == NULL) fatal("Local resource failure: malloc"); /* NOTREACHED */ return (new); } /* * As per fprintf(), but increment total_bytes and total_bytes_out, * by the appropriate amount. */ void cprintf(FILE *fd, const char *fmt, ...) { off_t b; va_list ap; va_start(ap, fmt); b = vfprintf(fd, fmt, ap); va_end(ap); total_bytes += b; total_bytes_out += b; } #ifdef USE_PAM /* * the following code is stolen from imap-uw PAM authentication module and * login.c */ #define COPY_STRING(s) (s ? strdup(s) : NULL) typedef struct { const char *uname; /* user name */ const char *pass; /* password */ } ftpd_cred_t; static int auth_conv(int num_msg, const struct pam_message **msg, struct pam_response **resp, void *appdata) { int i; ftpd_cred_t *cred = (ftpd_cred_t *) appdata; struct pam_response *myreply; myreply = calloc(num_msg, sizeof *myreply); if (myreply == NULL) return PAM_BUF_ERR; for (i = 0; i < num_msg; i++) { switch (msg[i]->msg_style) { case PAM_PROMPT_ECHO_ON: /* assume want user name */ myreply[i].resp_retcode = PAM_SUCCESS; myreply[i].resp = COPY_STRING(cred->uname); /* PAM frees resp. */ break; case PAM_PROMPT_ECHO_OFF: /* assume want password */ myreply[i].resp_retcode = PAM_SUCCESS; myreply[i].resp = COPY_STRING(cred->pass); /* PAM frees resp. */ break; case PAM_TEXT_INFO: case PAM_ERROR_MSG: myreply[i].resp_retcode = PAM_SUCCESS; myreply[i].resp = NULL; break; default: /* unknown message style */ free(myreply); return PAM_CONV_ERR; } } *resp = myreply; return PAM_SUCCESS; } /* * Attempt to authenticate the user using PAM. Returns 0 if the user is * authenticated, or 1 if not authenticated. If some sort of PAM system * error occurs (e.g., the "/etc/pam.conf" file is missing) then this * function returns -1. This can be used as an indication that we should * fall back to a different authentication mechanism. */ static int auth_pam(struct passwd **ppw, const char *pwstr) { const char *tmpl_user; const void *item; int rval; int e; ftpd_cred_t auth_cred = { (*ppw)->pw_name, pwstr }; struct pam_conv conv = { &auth_conv, &auth_cred }; e = pam_start("ftpd", (*ppw)->pw_name, &conv, &pamh); if (e != PAM_SUCCESS) { /* * In OpenPAM, it's OK to pass NULL to pam_strerror() * if context creation has failed in the first place. */ syslog(LOG_ERR, "pam_start: %s", pam_strerror(NULL, e)); return -1; } e = pam_set_item(pamh, PAM_RHOST, remotehost); if (e != PAM_SUCCESS) { syslog(LOG_ERR, "pam_set_item(PAM_RHOST): %s", pam_strerror(pamh, e)); if ((e = pam_end(pamh, e)) != PAM_SUCCESS) { syslog(LOG_ERR, "pam_end: %s", pam_strerror(pamh, e)); } pamh = NULL; return -1; } e = pam_set_item(pamh, PAM_SOCKADDR, &his_addr); if (e != PAM_SUCCESS) { syslog(LOG_ERR, "pam_set_item(PAM_SOCKADDR): %s", pam_strerror(pamh, e)); if ((e = pam_end(pamh, e)) != PAM_SUCCESS) { syslog(LOG_ERR, "pam_end: %s", pam_strerror(pamh, e)); } pamh = NULL; return -1; } e = pam_authenticate(pamh, 0); switch (e) { case PAM_SUCCESS: /* * With PAM we support the concept of a "template" * user. The user enters a login name which is * authenticated by PAM, usually via a remote service * such as RADIUS or TACACS+. If authentication * succeeds, a different but related "template" name * is used for setting the credentials, shell, and * home directory. The name the user enters need only * exist on the remote authentication server, but the * template name must be present in the local password * database. * * This is supported by two various mechanisms in the * individual modules. However, from the application's * point of view, the template user is always passed * back as a changed value of the PAM_USER item. */ if ((e = pam_get_item(pamh, PAM_USER, &item)) == PAM_SUCCESS) { tmpl_user = (const char *) item; if (strcmp((*ppw)->pw_name, tmpl_user) != 0) *ppw = sgetpwnam(tmpl_user); } else syslog(LOG_ERR, "Couldn't get PAM_USER: %s", pam_strerror(pamh, e)); rval = 0; break; case PAM_AUTH_ERR: case PAM_USER_UNKNOWN: case PAM_MAXTRIES: rval = 1; break; default: syslog(LOG_ERR, "pam_authenticate: %s", pam_strerror(pamh, e)); rval = -1; break; } if (rval == 0) { e = pam_acct_mgmt(pamh, 0); if (e != PAM_SUCCESS) { syslog(LOG_ERR, "pam_acct_mgmt: %s", pam_strerror(pamh, e)); rval = 1; } } if (rval != 0) { if ((e = pam_end(pamh, e)) != PAM_SUCCESS) { syslog(LOG_ERR, "pam_end: %s", pam_strerror(pamh, e)); } pamh = NULL; } return rval; } #endif /* USE_PAM */