/*- * Copyright (c) 1988, 1989, 1992, 1993, 1994 * The Regents of the University of California. All rights reserved. * Copyright (c) 2002 Networks Associates Technology, Inc. * All rights reserved. * * Portions of this software were developed for the FreeBSD Project by * ThinkSec AS and NAI Labs, the Security Research Division of Network * Associates, Inc. under DARPA/SPAWAR contract N66001-01-C-8035 * ("CBOSS"), as part of the DARPA CHATS research program. * * 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. */ #ifndef lint static const char copyright[] = "@(#) Copyright (c) 1988, 1989, 1992, 1993, 1994\n\ The Regents of the University of California. All rights reserved.\n"; #endif /* not lint */ #ifndef lint #if 0 static const char sccsid[] = "@(#)rshd.c 8.2 (Berkeley) 4/6/94"; #endif #endif /* not lint */ #include __FBSDID("$FreeBSD: src/libexec/rshd/rshd.c,v 1.51 2005/05/11 02:41:39 jmallett Exp $"); /* * remote shell server: * [port]\0 * ruser\0 * luser\0 * command\0 * data */ #include #include #include #include #include #include #include #include #include #include #include #include #include #ifndef __APPLE__ #include #endif #include #include #include #include #include #include #include #include #include #ifndef __APPLE__ #include #endif #ifdef __APPLE__ #include #endif #if !TARGET_OS_EMBEDDED #include #include #endif #include #if !TARGET_OS_EMBEDDED static struct pam_conv pamc = { openpam_nullconv, NULL }; static pam_handle_t *pamh; static int pam_err; #endif #define PAM_END { \ if ((pam_err = pam_setcred(pamh, PAM_DELETE_CRED)) != PAM_SUCCESS) \ syslog(LOG_ERR|LOG_AUTH, "pam_setcred(): %s", pam_strerror(pamh, pam_err)); \ if ((pam_err = pam_close_session(pamh,0)) != PAM_SUCCESS) \ syslog(LOG_ERR|LOG_AUTH, "pam_close_session(): %s", pam_strerror(pamh, pam_err)); \ if ((pam_err = pam_end(pamh, pam_err)) != PAM_SUCCESS) \ syslog(LOG_ERR|LOG_AUTH, "pam_end(): %s", pam_strerror(pamh, pam_err)); \ } int keepalive = 1; int check_all; int log_success; /* If TRUE, log all successful accesses */ int sent_null; int no_delay; #ifdef __APPLE__ #define __printf0like(a,b) #endif void doit(struct sockaddr *); static void rshd_errx(int, const char *, ...) __printf0like(2, 3); void getstr(char *, int, const char *); int local_domain(char *); char *topdomain(char *); void usage(void); char slash[] = "/"; char bshell[] = _PATH_BSHELL; #if defined(KERBEROS) #include #include #define VERSION_SIZE 9 #define SECURE_MESSAGE "This rsh session is using DES encryption for all transmissions.\r\n" #define OPTIONS "alnkvxL" char authbuf[sizeof(AUTH_DAT)]; char tickbuf[sizeof(KTEXT_ST)]; int doencrypt, use_kerberos, vacuous; Key_schedule schedule; #else #define OPTIONS "aDLln" #endif int main(int argc, char *argv[]) { extern int __check_rhosts_file; struct linger linger; socklen_t fromlen; int ch, on = 1; struct sockaddr_storage from; openlog("rshd", LOG_PID | LOG_ODELAY, LOG_DAEMON); opterr = 0; while ((ch = getopt(argc, argv, OPTIONS)) != -1) switch (ch) { case 'a': /* ignored for compatibility */ check_all = 1; break; case 'l': __check_rhosts_file = 0; break; case 'n': keepalive = 0; break; #if defined(KERBEROS) case 'k': use_kerberos = 1; break; case 'v': vacuous = 1; break; #if defined(CRYPT) case 'x': doencrypt = 1; break; #endif /* CRYPT */ #endif /* KERBEROS */ case 'D': no_delay = 1; break; case 'L': log_success = 1; break; case '?': default: usage(); break; } argc -= optind; argv += optind; #if defined(KERBEROS) if (use_kerberos && vacuous) { syslog(LOG_ERR, "only one of -k and -v allowed"); exit(2); } #if defined(CRYPT) if (doencrypt && !use_kerberos) { syslog(LOG_ERR, "-k is required for -x"); exit(2); } #endif /* CRYPT */ #endif /* KERBEROS */ fromlen = sizeof (from); if (getpeername(0, (struct sockaddr *)&from, &fromlen) < 0) { syslog(LOG_ERR, "getpeername: %m"); exit(1); } if (keepalive && setsockopt(0, SOL_SOCKET, SO_KEEPALIVE, (char *)&on, sizeof(on)) < 0) syslog(LOG_WARNING, "setsockopt (SO_KEEPALIVE): %m"); linger.l_onoff = 1; linger.l_linger = 60; /* XXX */ if (setsockopt(0, SOL_SOCKET, SO_LINGER, (char *)&linger, sizeof (linger)) < 0) syslog(LOG_WARNING, "setsockopt (SO_LINGER): %m"); if (no_delay && setsockopt(0, IPPROTO_TCP, TCP_NODELAY, &on, sizeof(on)) < 0) syslog(LOG_WARNING, "setsockopt (TCP_NODELAY): %m"); doit((struct sockaddr *)&from); /* NOTREACHED */ return(0); } #ifdef __APPLE__ char username[20] = "USER="; char homedir[64] = "HOME="; char shell[64] = "SHELL="; char path[100] = "PATH="; char *envinit[] = {homedir, shell, path, username, 0}; #endif extern char **environ; void doit(struct sockaddr *fromp) { extern char *__rcmd_errstr; /* syslog hook from libc/net/rcmd.c. */ struct passwd *pwd; u_short port; fd_set ready, readfrom; int cc, fd, nfd, pv[2], pid, s; int one = 1; const char *cp, *errorstr; char sig, buf[BUFSIZ]; char *cmdbuf, luser[16], ruser[16]; char rhost[2 * MAXHOSTNAMELEN + 1]; char numericname[INET6_ADDRSTRLEN]; int af, srcport; int maxcmdlen; #ifndef __APPLE__ login_cap_t *lc; #else struct hostent *hp; char *hostname, *errorhost = NULL; #endif maxcmdlen = (int)sysconf(_SC_ARG_MAX); if (maxcmdlen <= 0 || (cmdbuf = malloc(maxcmdlen)) == NULL) exit(1); #if defined(KERBEROS) AUTH_DAT *kdata = (AUTH_DAT *) NULL; KTEXT ticket = (KTEXT) NULL; char instance[INST_SZ], version[VERSION_SIZE]; struct sockaddr_in fromaddr; int rc; long authopts; int pv1[2], pv2[2]; fd_set wready, writeto; fromaddr = *fromp; #endif /* KERBEROS */ (void) signal(SIGINT, SIG_DFL); (void) signal(SIGQUIT, SIG_DFL); (void) signal(SIGTERM, SIG_DFL); af = fromp->sa_family; srcport = ntohs(*((in_port_t *)&fromp->sa_data)); if (af == AF_INET) { inet_ntop(af, &((struct sockaddr_in *)fromp)->sin_addr, numericname, sizeof numericname); } else if (af == AF_INET6) { inet_ntop(af, &((struct sockaddr_in6 *)fromp)->sin6_addr, numericname, sizeof numericname); } else { syslog(LOG_ERR, "malformed \"from\" address (af %d)", af); exit(1); } #ifdef IP_OPTIONS if (af == AF_INET) { u_char optbuf[BUFSIZ/3]; socklen_t optsize = sizeof(optbuf), ipproto, i; struct protoent *ip; if ((ip = getprotobyname("ip")) != NULL) ipproto = ip->p_proto; else ipproto = IPPROTO_IP; if (!getsockopt(0, ipproto, IP_OPTIONS, optbuf, &optsize) && optsize != 0) { for (i = 0; i < optsize; ) { u_char c = optbuf[i]; if (c == IPOPT_LSRR || c == IPOPT_SSRR) { syslog(LOG_NOTICE, "connection refused from %s with IP option %s", numericname, c == IPOPT_LSRR ? "LSRR" : "SSRR"); exit(1); } if (c == IPOPT_EOL) break; i += (c == IPOPT_NOP) ? 1 : optbuf[i+1]; } } } #endif #if defined(KERBEROS) if (!use_kerberos) #endif if (srcport >= IPPORT_RESERVED || srcport < IPPORT_RESERVED/2) { syslog(LOG_NOTICE|LOG_AUTH, "connection from %s on illegal port %u", numericname, srcport); exit(1); } (void) alarm(60); port = 0; s = 0; /* not set or used if port == 0 */ for (;;) { char c; if ((cc = read(STDIN_FILENO, &c, 1)) != 1) { if (cc < 0) syslog(LOG_NOTICE, "read: %m"); shutdown(0, SHUT_RDWR); exit(1); } if (c == 0) break; port = port * 10 + c - '0'; } (void) alarm(0); if (port != 0) { int lport = IPPORT_RESERVED - 1; s = rresvport_af(&lport, af); if (s < 0) { syslog(LOG_ERR, "can't get stderr port: %m"); exit(1); } #if defined(KERBEROS) if (!use_kerberos) #endif if (port >= IPPORT_RESERVED || port < IPPORT_RESERVED/2) { syslog(LOG_NOTICE|LOG_AUTH, "2nd socket from %s on unreserved port %u", numericname, port); exit(1); } *((in_port_t *)&fromp->sa_data) = htons(port); if (connect(s, fromp, fromp->sa_len) < 0) { syslog(LOG_INFO, "connect second port %d: %m", port); exit(1); } } #if defined(KERBEROS) if (vacuous) { error("rshd: remote host requires Kerberos authentication\n"); exit(1); } #endif errorstr = NULL; #ifndef __APPLE__ realhostname_sa(rhost, sizeof(rhost) - 1, fromp, fromp->sa_len); rhost[sizeof(rhost) - 1] = '\0'; /* XXX truncation! */ #else errorstr = NULL; hp = gethostbyaddr((char *)&((struct sockaddr_in *)fromp)->sin_addr, sizeof (struct in_addr), ((struct sockaddr_in *)fromp)->sin_family); if (hp) { /* * If name returned by gethostbyaddr is in our domain, * attempt to verify that we haven't been fooled by someone * in a remote net; look up the name and check that this * address corresponds to the name. */ hostname = hp->h_name; #if defined(KERBEROS) if (!use_kerberos) #endif if (check_all || local_domain(hp->h_name)) { strncpy(rhost, hp->h_name, sizeof(rhost) - 1); rhost[sizeof(rhost) - 1] = 0; errorhost = rhost; hp = gethostbyname(rhost); if (hp == NULL) { syslog(LOG_INFO, "Couldn't look up address for %s", rhost); errorstr = "Couldn't look up address for your host (%s)\n"; hostname = inet_ntoa(((struct sockaddr_in *)fromp)->sin_addr); } else for (; ; hp->h_addr_list++) { if (hp->h_addr_list[0] == NULL) { syslog(LOG_NOTICE, "Host addr %s not listed for host %s", inet_ntoa(((struct sockaddr_in *)fromp)->sin_addr), hp->h_name); errorstr = "Host address mismatch for %s\n"; hostname = inet_ntoa(((struct sockaddr_in *)fromp)->sin_addr); break; } if (!bcmp(hp->h_addr_list[0], (caddr_t)&((struct sockaddr_in *)fromp)->sin_addr, sizeof(((struct sockaddr_in *)fromp)->sin_addr))) { hostname = hp->h_name; break; } } } } else errorhost = hostname = inet_ntoa(((struct sockaddr_in *)fromp)->sin_addr); #if defined(KERBEROS) if (use_kerberos) { kdata = (AUTH_DAT *) authbuf; ticket = (KTEXT) tickbuf; authopts = 0L; strcpy(instance, "*"); version[VERSION_SIZE - 1] = '\0'; #if defined(CRYPT) if (doencrypt) { struct sockaddr_in local_addr; rc = sizeof(local_addr); if (getsockname(0, (struct sockaddr *)&local_addr, &rc) < 0) { syslog(LOG_ERR, "getsockname: %m"); error("rshd: getsockname: %m"); exit(1); } authopts = KOPT_DO_MUTUAL; rc = krb_recvauth(authopts, 0, ticket, "rcmd", instance, &fromaddr, &local_addr, kdata, "", schedule, version); des_set_key(kdata->session, schedule); } else #endif /* CRYPT */ rc = krb_recvauth(authopts, 0, ticket, "rcmd", instance, &fromaddr, (struct sockaddr_in *) 0, kdata, "", (bit_64 *) 0, version); if (rc != KSUCCESS) { error("Kerberos authentication failure: %s\n", krb_err_txt[rc]); exit(1); } } else #endif /* KERBEROS */ #endif (void) alarm(60); getstr(ruser, sizeof(ruser), "ruser"); getstr(luser, sizeof(luser), "luser"); getstr(cmdbuf, maxcmdlen, "command"); (void) alarm(0); #if !TARGET_OS_EMBEDDED pam_err = pam_start("rshd", luser, &pamc, &pamh); if (pam_err != PAM_SUCCESS) { syslog(LOG_ERR|LOG_AUTH, "pam_start(): %s", pam_strerror(pamh, pam_err)); rshd_errx(1, "Login incorrect."); } if ((pam_err = pam_set_item(pamh, PAM_RUSER, ruser)) != PAM_SUCCESS || (pam_err = pam_set_item(pamh, PAM_RHOST, rhost) != PAM_SUCCESS)) { syslog(LOG_ERR|LOG_AUTH, "pam_set_item(): %s", pam_strerror(pamh, pam_err)); rshd_errx(1, "Login incorrect."); } pam_err = pam_authenticate(pamh, 0); if (pam_err == PAM_SUCCESS) { if ((pam_err = pam_get_user(pamh, &cp, NULL)) == PAM_SUCCESS) { strncpy(luser, cp, sizeof(luser)); luser[sizeof(luser) - 1] = '\0'; /* XXX truncation! */ } pam_err = pam_acct_mgmt(pamh, 0); } if (pam_err != PAM_SUCCESS) { syslog(LOG_INFO|LOG_AUTH, "%s@%s as %s: permission denied (%s). cmd='%.80s'", ruser, rhost, luser, pam_strerror(pamh, pam_err), cmdbuf); rshd_errx(1, "Login incorrect."); } #endif setpwent(); pwd = getpwnam(luser); if (pwd == NULL) { syslog(LOG_INFO|LOG_AUTH, "%s@%s as %s: unknown login. cmd='%.80s'", ruser, rhost, luser, cmdbuf); if (errorstr == NULL) errorstr = "Login incorrect."; rshd_errx(1, errorstr, rhost); } #ifndef __APPLE__ lc = login_getpwclass(pwd); if (pwd->pw_uid) auth_checknologin(lc); #endif if (chdir(pwd->pw_dir) < 0) { if (chdir("/") < 0 || #ifndef __APPLE__ login_getcapbool(lc, "requirehome", !!pwd->pw_uid)) { #else 0) { #endif /* __APPLE__ */ #ifdef notdef syslog(LOG_INFO|LOG_AUTH, "%s@%s as %s: no home directory. cmd='%.80s'", ruser, rhost, luser, cmdbuf); rshd_errx(0, "No remote home directory."); #endif } pwd->pw_dir = slash; } #if defined(KERBEROS) if (use_kerberos) { if (pwd->pw_passwd != 0 && *pwd->pw_passwd != '\0') { if (kuserok(kdata, luser) != 0) { syslog(LOG_INFO|LOG_AUTH, "Kerberos rsh denied to %s.%s@%s", kdata->pname, kdata->pinst, kdata->prealm); error("Permission denied.\n"); exit(1); } } } else #endif #ifdef __APPLE__ if (errorstr || (pwd->pw_passwd != 0 && *pwd->pw_passwd != '\0' && iruserok(((struct sockaddr_in *)fromp)->sin_addr.s_addr, #if TARGET_OS_EMBEDDED // rdar://problem/5381734 0, #else pwd->pw_uid == 0, #endif ruser, luser) < 0)) { if (__rcmd_errstr) syslog(LOG_INFO|LOG_AUTH, "%s@%s as %s: permission denied (%s). cmd='%.80s'", ruser, rhost, luser, __rcmd_errstr, cmdbuf); else syslog(LOG_INFO|LOG_AUTH, "%s@%s as %s: permission denied. cmd='%.80s'", ruser, rhost, luser, cmdbuf); if (errorstr == NULL) errorstr = "Permission denied."; rshd_errx(1, errorstr, errorhost); } if (pwd->pw_uid && !access(_PATH_NOLOGIN, F_OK)) { rshd_errx(1, "Logins currently disabled."); } #else if (lc != NULL && fromp->sa_family == AF_INET) { /*XXX*/ char remote_ip[MAXHOSTNAMELEN]; strncpy(remote_ip, numericname, sizeof(remote_ip) - 1); remote_ip[sizeof(remote_ip) - 1] = 0; /* XXX truncation! */ if (!auth_hostok(lc, rhost, remote_ip)) { syslog(LOG_INFO|LOG_AUTH, "%s@%s as %s: permission denied (%s). cmd='%.80s'", ruser, rhost, luser, __rcmd_errstr, cmdbuf); rshd_errx(1, "Login incorrect."); } if (!auth_timeok(lc, time(NULL))) rshd_errx(1, "Logins not available right now"); } /* * PAM modules might add supplementary groups in * pam_setcred(), so initialize them first. * But we need to open the session as root. */ if (setusercontext(lc, pwd, pwd->pw_uid, LOGIN_SETGROUP) != 0) { syslog(LOG_ERR, "setusercontext: %m"); exit(1); } #endif /* !__APPLE__ */ #if !TARGET_OS_EMBEDDED if ((pam_err = pam_open_session(pamh, 0)) != PAM_SUCCESS) { syslog(LOG_ERR, "pam_open_session: %s", pam_strerror(pamh, pam_err)); } else if ((pam_err = pam_setcred(pamh, PAM_ESTABLISH_CRED)) != PAM_SUCCESS) { syslog(LOG_ERR, "pam_setcred: %s", pam_strerror(pamh, pam_err)); } #endif (void) write(STDERR_FILENO, "\0", 1); sent_null = 1; if (port) { if (pipe(pv) < 0) rshd_errx(1, "Can't make pipe."); #if defined(KERBEROS) && defined(CRYPT) if (doencrypt) { if (pipe(pv1) < 0) rshd_errx(1, "Can't make 2nd pipe."); if (pipe(pv2) < 0) rshd_errx(1, "Can't make 3rd pipe."); } #endif /* KERBEROS && CRYPT */ pid = fork(); if (pid == -1) rshd_errx(1, "Can't fork; try again."); if (pid) { #if defined(KERBEROS) && defined(CRYPT) if (doencrypt) { static char msg[] = SECURE_MESSAGE; (void) close(pv1[1]); (void) close(pv2[1]); des_write(s, msg, sizeof(msg) - 1); } else #endif /* KERBEROS && CRYPT */ (void) close(0); (void) close(1); (void) close(2); (void) close(pv[1]); FD_ZERO(&readfrom); FD_SET(s, &readfrom); FD_SET(pv[0], &readfrom); if (pv[0] > s) nfd = pv[0]; else nfd = s; #if defined(KERBEROS) && defined(CRYPT) if (doencrypt) { FD_ZERO(&writeto); FD_SET(pv2[0], &writeto); FD_SET(pv1[0], &readfrom); nfd = MAX(nfd, pv2[0]); nfd = MAX(nfd, pv1[0]); } else #endif /* KERBEROS && CRYPT */ ioctl(pv[0], FIONBIO, (char *)&one); /* should set s nbio! */ nfd++; do { ready = readfrom; #if defined(KERBEROS) && defined(CRYPT) if (doencrypt) { wready = writeto; if (select(nfd, &ready, &wready, (fd_set *) 0, (struct timeval *) 0) < 0) break; } else #endif /* KERBEROS && CRYPT */ if (select(nfd, &ready, (fd_set *)0, (fd_set *)0, (struct timeval *)0) < 0) break; if (FD_ISSET(s, &ready)) { int ret; #if defined(KERBEROS) && defined(CRYPT) if (doencrypt) ret = des_read(s, &sig, 1); else #endif /* KERBEROS && CRYPT */ ret = read(s, &sig, 1); if (ret <= 0) FD_CLR(s, &readfrom); else killpg(pid, sig); } if (FD_ISSET(pv[0], &ready)) { errno = 0; cc = read(pv[0], buf, sizeof(buf)); if (cc <= 0) { shutdown(s, SHUT_RDWR); FD_CLR(pv[0], &readfrom); } else { #if defined(KERBEROS) && defined(CRYPT) if (doencrypt) (void) des_write(s, buf, cc); else #endif /* KERBEROS && CRYPT */ (void)write(s, buf, cc); } } #if defined(KERBEROS) && defined(CRYPT) if (doencrypt && FD_ISSET(pv1[0], &ready)) { errno = 0; cc = read(pv1[0], buf, sizeof(buf)); if (cc <= 0) { shutdown(pv1[0], 1+1); FD_CLR(pv1[0], &readfrom); } else (void) des_write(STDOUT_FILENO, buf, cc); } if (doencrypt && FD_ISSET(pv2[0], &wready)) { errno = 0; cc = des_read(STDIN_FILENO, buf, sizeof(buf)); if (cc <= 0) { shutdown(pv2[0], 1+1); FD_CLR(pv2[0], &writeto); } else (void) write(pv2[0], buf, cc); } #endif /* KERBEROS && CRYPT */ } while (FD_ISSET(s, &readfrom) || #if defined(KERBEROS) && defined(CRYPT) (doencrypt && FD_ISSET(pv1[0], &readfrom)) || #endif /* KERBEROS && CRYPT */ FD_ISSET(pv[0], &readfrom)); #if !TARGET_OS_EMBEDDED PAM_END; #endif exit(0); } #ifdef __APPLE__ // rdar://problem/4485794 setpgid(0, getpid()); #endif (void) close(s); (void) close(pv[0]); #if defined(KERBEROS) && defined(CRYPT) if (doencrypt) { close(pv1[0]); close(pv2[0]); dup2(pv1[1], 1); dup2(pv2[1], 0); close(pv1[1]); close(pv2[1]); } #endif /* KERBEROS && CRYPT */ dup2(pv[1], 2); close(pv[1]); } #ifndef __APPLE__ else { pid = fork(); if (pid == -1) rshd_errx(1, "Can't fork; try again."); if (pid) { /* Parent. */ while (wait(NULL) > 0 || errno == EINTR) /* nothing */ ; PAM_END; exit(0); } } #endif for (fd = getdtablesize(); fd > 2; fd--) { #ifdef __APPLE__ (void) fcntl(fd, F_SETFD, FD_CLOEXEC); #else (void) close(fd); #endif } if (setsid() == -1) syslog(LOG_ERR, "setsid() failed: %m"); if (setlogin(pwd->pw_name) < 0) syslog(LOG_ERR, "setlogin() failed: %m"); if (*pwd->pw_shell == '\0') pwd->pw_shell = bshell; #ifdef __APPLE__ (void) setgid((gid_t)pwd->pw_gid); initgroups(pwd->pw_name, pwd->pw_gid); (void) setuid((uid_t)pwd->pw_uid); environ = envinit; strncat(homedir, pwd->pw_dir, sizeof(homedir)-6); strcat(path, _PATH_DEFPATH); strncat(shell, pwd->pw_shell, sizeof(shell)-7); strncat(username, pwd->pw_name, sizeof(username)-6); #endif #if !TARGET_OS_EMBEDDED (void) pam_setenv(pamh, "HOME", pwd->pw_dir, 1); (void) pam_setenv(pamh, "SHELL", pwd->pw_shell, 1); (void) pam_setenv(pamh, "USER", pwd->pw_name, 1); (void) pam_setenv(pamh, "PATH", _PATH_DEFPATH, 1); environ = pam_getenvlist(pamh); (void) pam_end(pamh, pam_err); #endif cp = strrchr(pwd->pw_shell, '/'); if (cp) cp++; else cp = pwd->pw_shell; #ifndef __APPLE__ if (setusercontext(lc, pwd, pwd->pw_uid, LOGIN_SETALL & ~LOGIN_SETGROUP) < 0) { syslog(LOG_ERR, "setusercontext(): %m"); exit(1); } login_close(lc); #endif endpwent(); if (log_success || pwd->pw_uid == 0) { #if defined(KERBEROS) if (use_kerberos) syslog(LOG_INFO|LOG_AUTH, "Kerberos shell from %s.%s@%s on %s as %s, cmd='%.80s'", kdata->pname, kdata->pinst, kdata->prealm, hostname, luser, cmdbuf); else #endif /* KERBEROS */ syslog(LOG_INFO|LOG_AUTH, "%s@%s as %s: cmd='%.80s'", ruser, rhost, luser, cmdbuf); } execl(pwd->pw_shell, cp, "-c", cmdbuf, (char *)NULL); err(1, "%s", pwd->pw_shell); exit(1); } /* * Report error to client. Note: can't be used until second socket has * connected to client, or older clients will hang waiting for that * connection first. */ static void rshd_errx(int errcode, const char *fmt, ...) { va_list ap; va_start(ap, fmt); if (sent_null == 0) write(STDERR_FILENO, "\1", 1); verrx(errcode, fmt, ap); /* NOTREACHED */ } void getstr(char *buf, int cnt, const char *error) { char c; do { if (read(STDIN_FILENO, &c, 1) != 1) exit(1); *buf++ = c; if (--cnt == 0) rshd_errx(1, "%s too long", error); } while (c != 0); } /* * Check whether host h is in our local domain, * defined as sharing the last two components of the domain part, * or the entire domain part if the local domain has only one component. * If either name is unqualified (contains no '.'), * assume that the host is local, as it will be * interpreted as such. */ int local_domain(char *h) { char localhost[MAXHOSTNAMELEN]; char *p1, *p2; localhost[0] = 0; (void) gethostname(localhost, sizeof(localhost) - 1); localhost[sizeof(localhost) - 1] = '\0'; /* XXX truncation! */ p1 = topdomain(localhost); p2 = topdomain(h); if (p1 == NULL || p2 == NULL || !strcasecmp(p1, p2)) return (1); return (0); } char * topdomain(char *h) { char *p, *maybe = NULL; int dots = 0; for (p = h + strlen(h); p >= h; p--) { if (*p == '.') { if (++dots == 2) return (p); maybe = p; } } return (maybe); } void usage(void) { syslog(LOG_ERR, "usage: rshd [-%s]", OPTIONS); exit(2); }