/* $NetBSD: ftpd.c,v 1.61 1998/12/28 04:54:01 lukem Exp $ */ /* * 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. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by the University of * California, Berkeley and its contributors. * 4. 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. */ #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 1.61 1998/12/28 04:54:01 lukem Exp $"); #endif #endif /* not lint */ /* * FTP server. */ #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 #ifdef SKEY #include #endif #ifdef KERBEROS5 #include #endif #include "extern.h" #include "pathnames.h" #if __STDC__ #include #else #include #endif #ifndef TRUE #define TRUE 1 #define FALSE 0 #endif const char version[] = "Version: 7.1.0"; struct sockaddr_in ctrl_addr; struct sockaddr_in data_source; struct sockaddr_in data_dest; struct sockaddr_in his_addr; struct sockaddr_in pasv_addr; int data; jmp_buf errcatch, urgcatch; int logged_in; struct passwd *pw; int debug; int sflag; int logging; int guest; int dochroot; int type; int form; int stru; /* avoid C keyword */ int mode; int usedefault = 1; /* for data transfers */ int pdata = -1; /* for passive mode */ sig_atomic_t transflag; off_t file_size; off_t byte_count; char tmpline[7]; char hostname[MAXHOSTNAMELEN+1]; char remotehost[MAXHOSTNAMELEN+1]; static char ttyline[20]; char *tty = ttyline; /* for klogin */ static char *anondir = NULL; static char confdir[MAXPATHLEN]; #if defined(KERBEROS) || defined(KERBEROS5) int notickets = 1; char *krbtkfile_env = NULL; #endif /* * 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; #ifdef HASSETPROCTITLE char proctitle[BUFSIZ]; /* initial part of title */ #endif /* HASSETPROCTITLE */ static void ack __P((char *)); static void myoob __P((int)); static int checkuser __P((const char *, const char *, int, int)); static int checkaccess __P((const char *)); static FILE *dataconn __P((char *, off_t, char *)); static void dolog __P((struct sockaddr_in *)); static void end_login __P((void)); static FILE *getdatasock __P((char *)); static char *gunique __P((char *)); static void lostconn __P((int)); static int receive_data __P((FILE *, FILE *)); static void replydirname __P((const char *, const char *)); static int send_data __P((FILE *, FILE *, off_t)); static struct passwd * sgetpwnam __P((const char *)); int main __P((int, char *[])); #if defined(KERBEROS) || defined(KERBEROS5) int klogin __P((struct passwd *, char *, char *, char *)); void kdestroy __P((void)); #endif int main(argc, argv) int argc; char *argv[]; { int addrlen, ch, on = 1, tos; char *cp, line[LINE_MAX]; FILE *fd; #ifdef KERBEROS5 krb5_error_code kerror; #endif debug = 0; logging = 0; sflag = 0; (void)strcpy(confdir, _DEFAULT_CONFDIR); while ((ch = getopt(argc, argv, "a:c:C:dlst:T:u:v")) != -1) { switch (ch) { case 'a': anondir = optarg; break; case 'c': (void)strncpy(confdir, optarg, sizeof(confdir)); confdir[sizeof(confdir)-1] = '\0'; break; case 'C': exit(checkaccess(optarg)); /* NOTREACHED */ case 'd': case 'v': /* deprecated */ debug = 1; break; case 'l': logging++; /* > 1 == extra logging */ break; case 's': sflag = 1; break; case 't': case 'T': case 'u': warnx("-%c has been deprecated in favour of ftpd.conf", ch); break; default: if (optopt == 'a' || optopt == 'C') exit(1); warnx("unknown flag -%c ignored", optopt); break; } } /* * 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); addrlen = sizeof(his_addr); if (getpeername(0, (struct sockaddr *)&his_addr, &addrlen) < 0) { syslog(LOG_ERR, "getpeername (%s): %m",argv[0]); exit(1); } addrlen = sizeof(ctrl_addr); if (getsockname(0, (struct sockaddr *)&ctrl_addr, &addrlen) < 0) { syslog(LOG_ERR, "getsockname (%s): %m",argv[0]); exit(1); } #ifdef IP_TOS tos = IPTOS_LOWDELAY; if (setsockopt(0, IPPROTO_IP, IP_TOS, (char *)&tos, sizeof(int)) < 0) syslog(LOG_WARNING, "setsockopt (IP_TOS): %m"); #endif data_source.sin_port = htons(ntohs(ctrl_addr.sin_port) - 1); /* set this here so klogin can use it... */ (void)snprintf(ttyline, sizeof(ttyline), "ftp%d", getpid()); (void) freopen(_PATH_DEVNULL, "w", stderr); (void) signal(SIGPIPE, lostconn); (void) signal(SIGCHLD, SIG_IGN); if ((long)signal(SIGURG, myoob) < 0) syslog(LOG_ERR, "signal: %m"); /* Try to handle urgent data inline */ #ifdef SO_OOBINLINE if (setsockopt(0, SOL_SOCKET, SO_OOBINLINE, (char *)&on, sizeof(on)) < 0) syslog(LOG_ERR, "setsockopt: %m"); #endif #ifdef F_SETOWN if (fcntl(fileno(stdin), F_SETOWN, getpid()) == -1) syslog(LOG_ERR, "fcntl F_SETOWN: %m"); #endif dolog(&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_NOTICE, "%s when initializing Kerberos context", error_message(kerror)); exit(0); } #endif /* KERBEROS5 */ /* If logins are disabled, print out the message. */ if ((fd = fopen(_PATH_NOLOGIN,"r")) != NULL) { while (fgets(line, sizeof(line), fd) != NULL) { if ((cp = strchr(line, '\n')) != NULL) *cp = '\0'; lreply(530, "%s", line); } (void) fflush(stdout); (void) fclose(fd); reply(530, "System not available."); exit(0); } if ((fd = fopen(conffilename(_PATH_FTPWELCOME), "r")) != NULL) { while (fgets(line, sizeof(line), fd) != NULL) { if ((cp = strchr(line, '\n')) != NULL) *cp = '\0'; lreply(220, "%s", line); } (void) fflush(stdout); (void) fclose(fd); /* reply(220,) must follow */ } (void)gethostname(hostname, sizeof(hostname)); hostname[sizeof(hostname) - 1] = '\0'; reply(220, "%s FTP server (%s) ready.", hostname, version); curclass.timeout = 300; /* 5 minutes, as per login(1) */ (void) setjmp(errcatch); for (;;) (void) yyparse(); /* NOTREACHED */ } static void lostconn(signo) int signo; { if (debug) syslog(LOG_DEBUG, "lost connection"); dologout(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(name) 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); 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 = xstrdup(p->pw_name); save.pw_passwd = xstrdup(p->pw_passwd); save.pw_gecos = xstrdup(p->pw_gecos); save.pw_dir = xstrdup(p->pw_dir); save.pw_shell = xstrdup(p->pw_shell); return (&save); } static int login_attempts; /* number of failed login attempts */ static int askpasswd; /* had user command, ask for passwd */ static char curname[10]; /* current USER name */ /* * 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 * _PATH_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 * _PATH_FTPUSERS to allow people such as root and uucp to be avoided. */ void user(name) char *name; { if (logged_in) { if (guest) { reply(530, "Can't change user from guest login."); return; } else if (dochroot) { reply(530, "Can't change user from chroot user."); return; } end_login(); } #if defined(KERBEROS) || defined(KERBEROS5) kdestroy(); #endif guest = 0; if (strcmp(name, "ftp") == 0 || strcmp(name, "anonymous") == 0) { if (checkaccess("ftp") || checkaccess("anonymous")) reply(530, "User %s access denied.", name); else if ((pw = sgetpwnam("ftp")) != NULL) { guest = 1; askpasswd = 1; reply(331, "Guest login ok, type your name as password."); } else reply(530, "User %s unknown.", name); if (!askpasswd && logging) syslog(LOG_NOTICE, "ANONYMOUS FTP LOGIN REFUSED FROM %s", remotehost); return; } pw = sgetpwnam(name); if (logging) strncpy(curname, name, sizeof(curname)-1); #ifdef SKEY if (skey_haskey(name) == 0) { char *myskey; myskey = skey_keyinfo(name); reply(331, "Password [%s] required for %s.", myskey ? myskey : "error getting challenge", name); } else #endif reply(331, "Password required for %s.", name); askpasswd = 1; /* * Delay before reading passwd after first failed * attempt to slow down passwd-guessing programs. */ if (login_attempts) sleep((unsigned) login_attempts); } /* * 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 compatability, `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 FALSE if the user is denied, or TRUE if they are allowed. */ int checkuser(fname, name, def, nofile) const char *fname, *name; int def, nofile; { FILE *fd; int retval; char *glob, *perm, line[BUFSIZ]; retval = def; if ((fd = fopen(conffilename(fname), "r")) == NULL) return nofile; while (fgets(line, sizeof(line), fd) != NULL) { glob = strtok(line, " \t\n"); if (glob[0] == '#') continue; perm = strtok(NULL, " \t\n"); if (fnmatch(glob, name, 0) == 0) { if (perm != NULL && ((strcasecmp(perm, "allow") == 0) || (strcasecmp(perm, "yes") == 0))) retval = TRUE; else if (perm != NULL && ((strcasecmp(perm, "deny") == 0) || (strcasecmp(perm, "no") == 0))) retval = FALSE; else retval = !def; break; } } (void) fclose(fd); return (retval); } /* * Check if user is allowed by /etc/ftpusers * returns 0 for yes, 1 for no */ int checkaccess(name) const char *name; { return (! checkuser(_PATH_FTPUSERS, name, TRUE, FALSE)); } /* * Terminate login as previous user, if any, resetting state; * used when USER command is given or login fails. */ static void end_login() { (void) seteuid((uid_t)0); if (logged_in) logwtmp(ttyline, "", ""); pw = NULL; logged_in = 0; guest = 0; dochroot = 0; } void pass(passwd) char *passwd; { int rval; FILE *fd; char const *cp, *shell, *home; if (logged_in || askpasswd == 0) { reply(503, "Login with USER first."); return; } askpasswd = 0; if (!guest) { /* "ftp" is only account allowed no password */ if (pw == NULL) { rval = 1; /* failure below */ goto skip; } #ifdef KERBEROS if (klogin(pw, "", hostname, passwd) == 0) { rval = 0; goto skip; } #endif #ifdef KERBEROS5 if (klogin(pw, "", hostname, passwd) == 0) { rval = 0; goto skip; } #endif #ifdef SKEY if (skey_haskey(pw->pw_name) == 0 && skey_passcheck(pw->pw_name, passwd) != -1) { rval = 0; goto skip; } #endif if (!sflag && *pw->pw_passwd != '\0' && !strcmp(crypt(passwd, pw->pw_passwd), pw->pw_passwd)) { rval = 0; goto skip; } rval = 1; skip: if (pw != NULL && pw->pw_expire && time(NULL) >= pw->pw_expire) rval = 2; /* * If rval > 0, the user failed the authentication check * above. If rval == 0, either Kerberos or local authentication * succeeded. */ if (rval) { reply(530, 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 was ok; see if anything else prevents login */ if (checkaccess(pw->pw_name)) { 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); pw = (struct passwd *) NULL; return; } /* check for valid shell, if not guest user */ 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 && guest == 0) { 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); pw = (struct passwd *) NULL; return; } login_attempts = 0; /* this time successful */ if (setegid((gid_t)pw->pw_gid) < 0) { reply(550, "Can't set gid."); return; } (void) initgroups(pw->pw_name, pw->pw_gid); /* open wtmp before chroot */ logwtmp(ttyline, pw->pw_name, remotehost); logged_in = 1; dochroot = checkuser(_PATH_FTPCHROOT, pw->pw_name, FALSE, FALSE); /* parse ftpd.conf, setting up various parameters */ if (guest) parse_conf(CLASS_GUEST); else if (dochroot) parse_conf(CLASS_CHROOT); else parse_conf(CLASS_REAL); home = "/"; if (guest) { /* * We MUST do a chdir() after the chroot. Otherwise * the old current directory will be accessible as "." * outside the new root! */ if (chroot(anondir ? anondir : pw->pw_dir) < 0 || chdir("/") < 0) { reply(550, "Can't set guest privileges."); goto bad; } } else if (dochroot) { if (chroot(pw->pw_dir) < 0 || chdir("/") < 0) { reply(550, "Can't change root."); goto bad; } } else if (chdir(pw->pw_dir) < 0) { if (chdir("/") < 0) { reply(530, "User %s: can't change directory to %s.", pw->pw_name, pw->pw_dir); goto bad; } else lreply(230, "No directory! Logging in with home=/"); } else home = pw->pw_dir; if (seteuid((uid_t)pw->pw_uid) < 0) { reply(550, "Can't set uid."); goto bad; } setenv("HOME", home, 1); /* * Display a login message, if it exists. * N.B. reply(230,) must follow the message. */ if ((fd = fopen(conffilename(_PATH_FTPLOGINMESG), "r")) != NULL) { char *cp, line[LINE_MAX]; while (fgets(line, sizeof(line), fd) != NULL) { if ((cp = strchr(line, '\n')) != NULL) *cp = '\0'; lreply(230, "%s", line); } (void) fflush(stdout); (void) fclose(fd); } show_chdir_messages(230); if (guest) { reply(230, "Guest login ok, access restrictions apply."); #ifdef HASSETPROCTITLE snprintf(proctitle, sizeof(proctitle), "%s: anonymous/%.*s", remotehost, (int) (sizeof(proctitle) - sizeof(remotehost) - sizeof(": anonymous/")), passwd); setproctitle(proctitle); #endif /* HASSETPROCTITLE */ if (logging) syslog(LOG_INFO, "ANONYMOUS FTP LOGIN FROM %s, %s", remotehost, passwd); } else { reply(230, "User %s logged in.", pw->pw_name); #ifdef HASSETPROCTITLE snprintf(proctitle, sizeof(proctitle), "%s: %s", remotehost, pw->pw_name); setproctitle(proctitle); #endif /* HASSETPROCTITLE */ if (logging) syslog(LOG_INFO, "FTP LOGIN FROM %s as %s", remotehost, pw->pw_name); } (void) umask(curclass.umask); return; bad: /* Forget all about it... */ end_login(); } void retrieve(cmd, name) char *cmd, *name; { FILE *fin = NULL, *dout; struct stat st; int (*closefunc) __P((FILE *)) = NULL; int log, sendrv, closerv, stderrfd, isconversion; sendrv = closerv = stderrfd = -1; isconversion = 0; log = (cmd == 0); if (cmd == NULL) { fin = fopen(name, "r"), closefunc = fclose; if (fin == NULL) cmd = do_conversion(name); if (cmd != NULL) { isconversion++; syslog(LOG_INFO, "get command: '%s'", cmd); } } if (cmd != NULL) { char line[BUFSIZ]; char temp[MAXPATHLEN + 1]; (void)snprintf(temp, sizeof(temp), "%s", TMPFILE); stderrfd = mkstemp(temp); if (stderrfd != -1) (void)unlink(temp); (void)snprintf(line, sizeof(line), cmd, name), name = line; fin = ftpd_popen(line, "r", stderrfd), closefunc = ftpd_pclose; st.st_size = -1; st.st_blksize = BUFSIZ; } if (fin == NULL) { if (errno != 0) { perror_reply(550, name); if (log) { logcmd("get", -1, name, NULL); } } if (stderrfd != -1) (void)close(stderrfd); return; } byte_count = -1; if (cmd == NULL && (fstat(fileno(fin), &st) < 0 || !S_ISREG(st.st_mode))) { reply(550, "%s: not a plain file.", name); 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) { perror_reply(550, name); goto done; } if (c == '\n') i++; } } else if (lseek(fileno(fin), restart_point, SEEK_SET) < 0) { perror_reply(550, name); goto done; } } dout = dataconn(name, st.st_size, "w"); if (dout == NULL) goto done; sendrv = send_data(fin, dout, st.st_blksize); (void) fclose(dout); data = -1; pdata = -1; done: if (log) logcmd("get", byte_count, name, NULL); closerv = (*closefunc)(fin); if (sendrv == 0) { FILE *err; struct stat sb; if (cmd != NULL && closerv != 0) { lreply(226, "Command returned an exit status of %d", closerv); if (isconversion) syslog(LOG_INFO, "get command: '%s' returned %d", cmd, closerv); } if (cmd != NULL && stderrfd != -1 && (fstat(stderrfd, &sb) == 0) && sb.st_size > 0 && ((err = fdopen(stderrfd, "r")) != NULL)) { char *cp, line[LINE_MAX]; lreply(226, "Command error messages:"); rewind(err); while (fgets(line, sizeof(line), err) != NULL) { if ((cp = strchr(line, '\n')) != NULL) *cp = '\0'; lreply(226, " %s", line); } (void) fflush(stdout); (void) fclose(err); lreply(226, "End of command error messages."); /* a reply(226,) must follow */ } reply(226, "Transfer complete."); } if (stderrfd != -1) (void)close(stderrfd); } void store(name, mode, unique) char *name, *mode; int unique; { FILE *fout, *din; struct stat st; int (*closefunc) __P((FILE *)); if (unique && stat(name, &st) == 0 && (name = gunique(name)) == NULL) { logcmd(*mode == 'w' ? "put" : "append", -1, name, NULL); return; } if (restart_point) mode = "r+"; fout = fopen(name, mode); closefunc = fclose; if (fout == NULL) { perror_reply(553, name); logcmd(*mode == 'w' ? "put" : "append", -1, name, NULL); return; } 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) { 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) { perror_reply(550, name); goto done; } } else if (lseek(fileno(fout), restart_point, SEEK_SET) < 0) { perror_reply(550, name); goto done; } } din = dataconn(name, (off_t)-1, "r"); if (din == NULL) goto done; if (receive_data(din, fout) == 0) { if (unique) reply(226, "Transfer complete (unique file name:%s).", name); else reply(226, "Transfer complete."); } (void) fclose(din); data = -1; pdata = -1; done: logcmd(*mode == 'w' ? "put" : "append", byte_count, name, NULL); (*closefunc)(fout); } static FILE * getdatasock(mode) char *mode; { int on = 1, s, t, tries; if (data >= 0) return (fdopen(data, mode)); (void) seteuid((uid_t)0); s = socket(AF_INET, SOCK_STREAM, 0); if (s < 0) goto bad; if (setsockopt(s, SOL_SOCKET, SO_REUSEADDR, (char *) &on, sizeof(on)) < 0) goto bad; /* anchor socket to avoid multi-homing problems */ data_source.sin_len = sizeof(struct sockaddr_in); data_source.sin_family = AF_INET; data_source.sin_addr = ctrl_addr.sin_addr; for (tries = 1; ; tries++) { if (bind(s, (struct sockaddr *)&data_source, sizeof(data_source)) >= 0) break; if (errno != EADDRINUSE || tries > 10) goto bad; sleep(tries); } (void) seteuid((uid_t)pw->pw_uid); #ifdef IP_TOS 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, mode)); bad: /* Return the real value of errno (close may change it) */ t = errno; (void) seteuid((uid_t)pw->pw_uid); (void) close(s); errno = t; return (NULL); } static FILE * dataconn(name, size, mode) char *name; off_t size; char *mode; { char sizebuf[32]; FILE *file; int retry = 0, tos; file_size = size; byte_count = 0; if (size != (off_t) -1) (void)snprintf(sizebuf, sizeof(sizebuf), " (%qd bytes)", (long long)size); else sizebuf[0] = '\0'; if (pdata >= 0) { struct sockaddr_in from; int s, fromlen = sizeof(from); (void) alarm(curclass.timeout); s = accept(pdata, (struct sockaddr *)&from, &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; #ifdef IP_TOS tos = IPTOS_THROUGHPUT; (void) setsockopt(s, IPPROTO_IP, IP_TOS, (char *)&tos, sizeof(int)); #endif reply(150, "Opening %s mode data connection for '%s'%s.", type == TYPE_A ? "ASCII" : "BINARY", name, sizebuf); return (fdopen(pdata, mode)); } if (data >= 0) { reply(125, "Using existing data connection for '%s'%s.", name, sizebuf); usedefault = 1; return (fdopen(data, mode)); } if (usedefault) data_dest = his_addr; usedefault = 1; file = getdatasock(mode); if (file == NULL) { reply(425, "Can't create data socket (%s,%d): %s.", inet_ntoa(data_source.sin_addr), ntohs(data_source.sin_port), strerror(errno)); return (NULL); } data = fileno(file); while (connect(data, (struct sockaddr *)&data_dest, sizeof(data_dest)) < 0) { if (errno == EADDRINUSE && retry < swaitmax) { sleep((unsigned) swaitint); retry += swaitint; continue; } perror_reply(425, "Can't build data connection"); (void) fclose(file); data = -1; return (NULL); } reply(150, "Opening %s mode data connection for '%s'%s.", type == TYPE_A ? "ASCII" : "BINARY", name, sizebuf); return (file); } /* * 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(instr, outstr, blksize) FILE *instr, *outstr; off_t blksize; { int c, cnt, filefd, netfd; char *buf; transflag++; if (setjmp(urgcatch)) { transflag = 0; return (-1); } switch (type) { case TYPE_A: while ((c = getc(instr)) != EOF) { byte_count++; if (c == '\n') { if (ferror(outstr)) goto data_err; (void) putc('\r', outstr); } (void) putc(c, outstr); } fflush(outstr); transflag = 0; if (ferror(instr)) goto file_err; if (ferror(outstr)) goto data_err; return (0); case TYPE_I: case TYPE_L: if ((buf = malloc((u_int)blksize)) == NULL) { transflag = 0; perror_reply(451, "Local resource failure: malloc"); return (-1); } netfd = fileno(outstr); filefd = fileno(instr); while ((cnt = read(filefd, buf, (u_int)blksize)) > 0 && write(netfd, buf, cnt) == cnt) byte_count += cnt; transflag = 0; (void)free(buf); if (cnt != 0) { if (cnt < 0) goto file_err; goto data_err; } return (0); default: transflag = 0; reply(550, "Unimplemented TYPE %d in send_data", type); return (-1); } data_err: transflag = 0; perror_reply(426, "Data connection"); return (-1); file_err: transflag = 0; perror_reply(551, "Error on input file"); return (-1); } /* * 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(instr, outstr) FILE *instr, *outstr; { int c, cnt, bare_lfs; char buf[BUFSIZ]; #ifdef __GNUC__ (void) &bare_lfs; #endif bare_lfs = 0; transflag++; if (setjmp(urgcatch)) { transflag = 0; return (-1); } switch (type) { case TYPE_I: case TYPE_L: while ((cnt = read(fileno(instr), buf, sizeof(buf))) > 0) { if (write(fileno(outstr), buf, cnt) != cnt) goto file_err; byte_count += cnt; } if (cnt < 0) goto data_err; transflag = 0; return (0); case TYPE_E: reply(553, "TYPE E not implemented."); transflag = 0; return (-1); case TYPE_A: while ((c = getc(instr)) != EOF) { byte_count++; if (c == '\n') bare_lfs++; while (c == '\r') { if (ferror(outstr)) goto data_err; if ((c = getc(instr)) != '\n') { (void) putc ('\r', outstr); if (c == '\0' || c == EOF) goto contin2; } } (void) putc(c, outstr); contin2: ; } fflush(outstr); if (ferror(instr)) goto data_err; if (ferror(outstr)) goto file_err; transflag = 0; if (bare_lfs) { lreply(226, "WARNING! %d bare linefeeds received in ASCII mode", bare_lfs); (void)printf(" File may not have transferred correctly.\r\n"); } return (0); default: reply(550, "Unimplemented TYPE %d in receive_data", type); transflag = 0; return (-1); } data_err: transflag = 0; perror_reply(426, "Data Connection"); return (-1); file_err: transflag = 0; perror_reply(452, "Error writing file"); return (-1); } void statfilecmd(filename) char *filename; { FILE *fin; int c; char line[LINE_MAX]; (void)snprintf(line, sizeof(line), "/bin/ls -lgA %s", filename); fin = ftpd_popen(line, "r", STDOUT_FILENO); lreply(211, "status of %s:", filename); while ((c = getc(fin)) != EOF) { if (c == '\n') { if (ferror(stdout)){ perror_reply(421, "control connection"); (void) ftpd_pclose(fin); dologout(1); /* NOTREACHED */ } if (ferror(fin)) { perror_reply(551, filename); (void) ftpd_pclose(fin); return; } (void) putc('\r', stdout); } (void) putc(c, stdout); } (void) ftpd_pclose(fin); reply(211, "End of Status"); } void statcmd() { struct sockaddr_in *sin; u_char *a, *p; lreply(211, "%s FTP server status:", hostname); lreply(211, "%s", version); if (isdigit(remotehost[0])) lreply(211, "Connected to %s", remotehost); else lreply(211, "Connected to %s (%s)", remotehost, inet_ntoa(his_addr.sin_addr)); if (logged_in) { if (guest) lreply(211, "Logged in anonymously"); else lreply(211, "Logged in as %s", pw->pw_name); } else if (askpasswd) lreply(211, "Waiting for password"); else lreply(211, "Waiting for user name"); printf("211- TYPE: %s", typenames[type]); if (type == TYPE_A || type == TYPE_E) printf(", FORM: %s", formnames[form]); if (type == TYPE_L) #if NBBY == 8 printf(" %d", NBBY); #else printf(" %d", bytesize); /* need definition! */ #endif printf("; STRUcture: %s; transfer MODE: %s\r\n", strunames[stru], modenames[mode]); if (data != -1) lreply(211, "Data connection open"); else if (pdata != -1) { printf("211- in Passive mode"); sin = &pasv_addr; goto printaddr; } else if (usedefault == 0) { printf("211- PORT"); sin = &data_dest; printaddr: a = (u_char *) &sin->sin_addr; p = (u_char *) &sin->sin_port; #define UC(b) (((int) b) & 0xff) printf(" (%d,%d,%d,%d,%d,%d)\r\n", UC(a[0]), UC(a[1]), UC(a[2]), UC(a[3]), UC(p[0]), UC(p[1])); #undef UC } else lreply(211, "No data connection"); if (logged_in) { struct ftpconv *cp; lreply(211, ""); lreply(211, "Class: %s", curclass.classname); lreply(211, "Check PORT commands: %sabled", curclass.checkportcmd ? "en" : "dis"); if (curclass.display) lreply(211, "Display file: %s", curclass.display); if (curclass.notify) lreply(211, "Notify fileglob: %s", curclass.notify); lreply(211, "Idle timeout: %d, maximum timeout: %d", curclass.timeout, curclass.maxtimeout); lreply(211, "DELE, MKD, RMD, UMASK, CHMOD commands: %sabled", curclass.modify ? "en" : "dis"); lreply(211, "Umask: %.04o", curclass.umask); for (cp = curclass.conversions; cp != NULL; cp=cp->next) { if (cp->suffix == NULL || cp->types == NULL || cp->command == NULL) continue; lreply(211, "Conversion: %s [%s] disable: %s, command: %s", cp->suffix, cp->types, cp->disable, cp->command); } } reply(211, "End of status"); } void fatal(s) char *s; { reply(451, "Error in server: %s\n", s); reply(221, "Closing connection due to server error."); dologout(0); /* NOTREACHED */ } void #ifdef __STDC__ reply(int n, const char *fmt, ...) #else reply(n, fmt, va_alist) int n; char *fmt; va_dcl #endif { va_list ap; #ifdef __STDC__ va_start(ap, fmt); #else va_start(ap); #endif (void)printf("%d ", n); (void)vprintf(fmt, ap); (void)printf("\r\n"); (void)fflush(stdout); if (debug) { syslog(LOG_DEBUG, "<--- %d ", n); vsyslog(LOG_DEBUG, fmt, ap); } } void #ifdef __STDC__ lreply(int n, const char *fmt, ...) #else lreply(n, fmt, va_alist) int n; char *fmt; va_dcl #endif { va_list ap; #ifdef __STDC__ va_start(ap, fmt); #else va_start(ap); #endif (void)printf("%d- ", n); (void)vprintf(fmt, ap); (void)printf("\r\n"); (void)fflush(stdout); if (debug) { syslog(LOG_DEBUG, "<--- %d- ", n); vsyslog(LOG_DEBUG, fmt, ap); } } static void ack(s) char *s; { reply(250, "%s command successful.", s); } void delete(name) char *name; { logcmd("delete", -1, name, NULL); if (remove(name) < 0) perror_reply(550, name); else ack("DELE"); } void cwd(path) const char *path; { if (chdir(path) < 0) perror_reply(550, path); else { show_chdir_messages(250); ack("CWD"); } } static void replydirname(name, message) const char *name, *message; { char npath[MAXPATHLEN + 1]; int i; for (i = 0; *name != '\0' && i < sizeof(npath) - 1; i++, name++) { npath[i] = *name; if (*name == '"') npath[++i] = '"'; } npath[i] = '\0'; reply(257, "\"%s\" %s", npath, message); } void makedir(name) char *name; { logcmd("mkdir", -1, name, NULL); if (mkdir(name, 0777) < 0) perror_reply(550, name); else replydirname(name, "directory created."); } void removedir(name) char *name; { logcmd("rmdir", -1, name, NULL); if (rmdir(name) < 0) perror_reply(550, name); else ack("RMD"); } void pwd() { char path[MAXPATHLEN + 1]; if (getcwd(path, sizeof(path) - 1) == NULL) reply(550, "Can't get the current directory: %s.", strerror(errno)); else replydirname(path, "is the current directory."); } char * renamefrom(name) char *name; { struct stat st; if (stat(name, &st) < 0) { perror_reply(550, name); return (NULL); } reply(350, "File exists, ready for destination name"); return (name); } void renamecmd(from, to) char *from, *to; { logcmd("rename", -1, from, to); if (rename(from, to) < 0) perror_reply(550, "rename"); else ack("RNTO"); } static void dolog(sin) struct sockaddr_in *sin; { struct hostent *hp = gethostbyaddr((char *)&sin->sin_addr, sizeof(struct in_addr), AF_INET); if (hp) (void)strncpy(remotehost, hp->h_name, sizeof(remotehost)); else (void)strncpy(remotehost, inet_ntoa(sin->sin_addr), sizeof(remotehost)); remotehost[sizeof(remotehost) - 1] = '\0'; #ifdef HASSETPROCTITLE snprintf(proctitle, sizeof(proctitle), "%s: connected", remotehost); setproctitle(proctitle); #endif /* HASSETPROCTITLE */ if (logging) syslog(LOG_INFO, "connection from %s", remotehost); } /* * Record logout in wtmp file * and exit with supplied status. */ void dologout(status) int status; { /* * Prevent reception of SIGURG from resulting in a resumption * back to the main program loop. */ transflag = 0; if (logged_in) { (void) seteuid((uid_t)0); logwtmp(ttyline, "", ""); #ifdef KERBEROS if (!notickets && krbtkfile_env) unlink(krbtkfile_env); #endif } /* beware of flushing buffers after a SIGPIPE */ _exit(status); } static void myoob(signo) int signo; { char *cp; /* only process if transfer occurring */ if (!transflag) return; cp = tmpline; if (getline(cp, 7, stdin) == NULL) { reply(221, "You could at least say goodbye."); dologout(0); } if (strcasecmp(cp, "ABOR\r\n") == 0) { tmpline[0] = '\0'; reply(426, "Transfer aborted. Data connection closed."); reply(226, "Abort successful"); longjmp(urgcatch, 1); } if (strcasecmp(cp, "STAT\r\n") == 0) { if (file_size != (off_t) -1) reply(213, "Status: %qd of %qd bytes transferred", byte_count, file_size); else reply(213, "Status: %qd bytes transferred", byte_count); } } /* * 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() { int len; char *p, *a; 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; pasv_addr.sin_port = 0; (void) seteuid((uid_t)0); if (bind(pdata, (struct sockaddr *)&pasv_addr, sizeof(pasv_addr)) < 0) { (void) seteuid((uid_t)pw->pw_uid); goto pasv_error; } (void) seteuid((uid_t)pw->pw_uid); len = sizeof(pasv_addr); if (getsockname(pdata, (struct sockaddr *) &pasv_addr, &len) < 0) goto pasv_error; if (listen(pdata, 1) < 0) goto pasv_error; a = (char *) &pasv_addr.sin_addr; p = (char *) &pasv_addr.sin_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; } /* * 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(local) char *local; { static char new[MAXPATHLEN + 1]; struct stat st; int count, len; char *cp; cp = strrchr(local, '/'); if (cp) *cp = '\0'; if (stat(cp ? local : ".", &st) < 0) { perror_reply(553, cp ? local : "."); return (NULL); } if (cp) *cp = '/'; (void) strcpy(new, local); len = strlen(new); cp = new + len; *cp++ = '.'; for (count = 1; count < 100; count++) { (void)snprintf(cp, sizeof(new) - len - 2, "%d", 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(code, string) int code; const char *string; { reply(code, "%s: %s.", string, strerror(errno)); } static char *onefile[] = { "", 0 }; void send_file_list(whichf) char *whichf; { struct stat st; DIR *dirp = NULL; struct dirent *dir; FILE *dout = NULL; char **dirlist, *dirname; int simple = 0; int freeglob = 0; glob_t gl; #ifdef __GNUC__ (void) &dout; (void) &dirlist; (void) &simple; (void) &freeglob; #endif if (strpbrk(whichf, "~{[*?") != NULL) { int flags = GLOB_BRACE|GLOB_NOCHECK|GLOB_TILDE; memset(&gl, 0, sizeof(gl)); freeglob = 1; if (glob(whichf, flags, 0, &gl)) { reply(550, "not found"); goto out; } else if (gl.gl_pathc == 0) { errno = ENOENT; perror_reply(550, whichf); goto out; } dirlist = gl.gl_pathv; } else { onefile[0] = whichf; dirlist = onefile; simple = 1; } if (setjmp(urgcatch)) { transflag = 0; goto out; } 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. */ if (dirname[0] == '-' && *dirlist == NULL && transflag == 0) { retrieve("/bin/ls %s", dirname); goto out; } perror_reply(550, whichf); if (dout != NULL) { (void) fclose(dout); transflag = 0; data = -1; pdata = -1; } goto out; } if (S_ISREG(st.st_mode)) { if (dout == NULL) { dout = dataconn("file list", (off_t)-1, "w"); if (dout == NULL) goto out; transflag++; } fprintf(dout, "%s%s\n", dirname, type == TYPE_A ? "\r" : ""); byte_count += strlen(dirname) + 1; 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 + 1]; if (dir->d_name[0] == '.' && dir->d_namlen == 1) continue; if (dir->d_name[0] == '.' && dir->d_name[1] == '.' && dir->d_namlen == 2) 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. */ 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 out; transflag++; } if (nbuf[0] == '.' && nbuf[1] == '/') fprintf(dout, "%s%s\n", &nbuf[2], type == TYPE_A ? "\r" : ""); else fprintf(dout, "%s%s\n", nbuf, type == TYPE_A ? "\r" : ""); byte_count += strlen(nbuf) + 1; } } (void) closedir(dirp); } if (dout == NULL) reply(550, "No files found."); else if (ferror(dout) != 0) perror_reply(550, "Data connection"); else reply(226, "Transfer complete."); transflag = 0; if (dout != NULL) (void) fclose(dout); data = -1; pdata = -1; out: if (freeglob) { freeglob = 0; globfree(&gl); } } char * conffilename(s) const char *s; { static char filename[MAXPATHLEN + 1]; (void)snprintf(filename, sizeof(filename), "%s/%s", confdir ,s); return filename; }