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);
}
void
doit(struct sockaddr *fromp)
{
extern char *__rcmd_errstr; /* syslog hook from libc/net/rcmd.c. */
struct addrinfo hints, *res, *res0;
int gaierror;
struct passwd *pwd;
u_short port;
in_port_t *portp;
struct pollfd pfd[4];
int cc, nfd, pv[2], s = 0, one = 1;
pid_t pid;
char *hostname, *errorstr, *errorhost = (char *) NULL;
char *cp, sig, buf[BUFSIZ];
char cmdbuf[NCARGS+1], locuser[_PW_NAME_LEN+1], remuser[_PW_NAME_LEN+1];
char remotehost[2 * MAXHOSTNAMELEN + 1];
char hostnamebuf[2 * MAXHOSTNAMELEN + 1];
char naddr[NI_MAXHOST];
char saddr[NI_MAXHOST];
char raddr[NI_MAXHOST];
char pbuf[NI_MAXSERV];
auth_session_t *as;
const int niflags = NI_NUMERICHOST | NI_NUMERICSERV;
#ifdef KERBEROS
AUTH_DAT *kdata = (AUTH_DAT *) NULL;
KTEXT ticket = (KTEXT) NULL;
char instance[INST_SZ], version[VERSION_SIZE];
struct sockaddr_storage fromaddr;
int rc;
long authopts;
#ifdef CRYPT
int pv1[2], pv2[2];
#endif
if (sizeof(fromaddr) < fromp->sa_len) {
syslog(LOG_ERR, "malformed \"from\" address (af %d)",
fromp->sa_family);
exit(1);
}
memcpy(&fromaddr, fromp, fromp->sa_len);
#endif
(void) signal(SIGINT, SIG_DFL);
(void) signal(SIGQUIT, SIG_DFL);
(void) signal(SIGTERM, SIG_DFL);
#ifdef DEBUG
{ int t = open(_PATH_TTY, 2);
if (t >= 0) {
ioctl(t, TIOCNOTTY, (char *)0);
(void) close(t);
}
}
#endif
switch (fromp->sa_family) {
case AF_INET:
portp = &((struct sockaddr_in *)fromp)->sin_port;
break;
case AF_INET6:
portp = &((struct sockaddr_in6 *)fromp)->sin6_port;
break;
default:
syslog(LOG_ERR, "malformed \"from\" address (af %d)",
fromp->sa_family);
exit(1);
}
if (getnameinfo(fromp, fromp->sa_len, naddr, sizeof(naddr),
pbuf, sizeof(pbuf), niflags) != 0) {
syslog(LOG_ERR, "malformed \"from\" address (af %d)",
fromp->sa_family);
exit(1);
}
#ifdef IP_OPTIONS
if (fromp->sa_family == AF_INET) {
struct ipoption opts;
socklen_t optsize = sizeof(opts);
int ipproto, i;
struct protoent *ip;
if ((ip = getprotobyname("ip")) != NULL)
ipproto = ip->p_proto;
else
ipproto = IPPROTO_IP;
if (!getsockopt(STDIN_FILENO, ipproto, IP_OPTIONS,
(char *)&opts, &optsize) && optsize != 0) {
for (i = 0; (void *)&opts.ipopt_list[i] - (void *)&opts <
optsize; ) {
u_char c = (u_char)opts.ipopt_list[i];
if (c == IPOPT_LSRR || c == IPOPT_SSRR)
exit(1);
if (c == IPOPT_EOL)
break;
i += (c == IPOPT_NOP) ? 1 :
(u_char)opts.ipopt_list[i+1];
}
}
}
#endif
#ifdef KERBEROS
if (!use_kerberos)
#endif
if (ntohs(*portp) >= IPPORT_RESERVED ||
ntohs(*portp) < IPPORT_RESERVED/2) {
syslog(LOG_NOTICE|LOG_AUTH,
"Connection from %s on illegal port %u",
naddr, ntohs(*portp));
exit(1);
}
(void) alarm(60);
port = 0;
for (;;) {
char c;
if ((cc = read(STDIN_FILENO, &c, 1)) != 1) {
if (cc < 0)
syslog(LOG_NOTICE, "read: %m");
shutdown(STDIN_FILENO, SHUT_RDWR);
exit(1);
}
if (c == 0)
break;
port = port * 10 + c - '0';
}
(void) alarm(0);
if (port != 0) {
int lport;
#ifdef KERBEROS
if (!use_kerberos)
#endif
if (port >= IPPORT_RESERVED ||
port < IPPORT_RESERVED/2) {
syslog(LOG_ERR, "2nd port not reserved");
exit(1);
}
*portp = htons(port);
lport = IPPORT_RESERVED - 1;
s = rresvport_af(&lport, fromp->sa_family);
if (s < 0) {
syslog(LOG_ERR, "can't get stderr port: %m");
exit(1);
}
if (connect(s, (struct sockaddr *)fromp, fromp->sa_len) < 0) {
syslog(LOG_INFO, "connect second port %d: %m", port);
exit(1);
}
}
#ifdef KERBEROS
if (vacuous) {
error("rshd: remote host requires Kerberos authentication\n");
exit(1);
}
#endif
#ifdef notdef
/* from inetd, socket is already on 0, 1, 2 */
dup2(f, 0);
dup2(f, 1);
dup2(f, 2);
#endif
errorstr = NULL;
if (getnameinfo(fromp, fromp->sa_len, saddr, sizeof(saddr),
NULL, 0, NI_NAMEREQD)== 0) {
/*
* If name returned by getnameinfo 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 = saddr;
res0 = NULL;
#ifdef KERBEROS
if (!use_kerberos)
#endif
if (check_all || local_domain(saddr)) {
strlcpy(remotehost, saddr, sizeof(remotehost));
errorhost = remotehost;
memset(&hints, 0, sizeof(hints));
hints.ai_family = fromp->sa_family;
hints.ai_socktype = SOCK_STREAM;
hints.ai_flags = AI_CANONNAME;
gaierror = getaddrinfo(remotehost, pbuf, &hints, &res0);
if (gaierror) {
syslog(LOG_INFO,
"Couldn't look up address for %s: %s",
remotehost, gai_strerror(gaierror));
errorstr =
"Couldn't look up address for your host (%s)\n";
hostname = naddr;
} else {
for (res = res0; res; res = res->ai_next) {
if (res->ai_family != fromp->sa_family)
continue;
if (res->ai_addrlen != fromp->sa_len)
continue;
if (getnameinfo(res->ai_addr,
res->ai_addrlen,
raddr, sizeof(raddr), NULL, 0,
niflags) == 0
&& strcmp(naddr, raddr) == 0) {
hostname = res->ai_canonname
? res->ai_canonname
: saddr;
break;
}
}
if (res == NULL) {
syslog(LOG_NOTICE,
"Host addr %s not listed for host %s",
naddr, res0->ai_canonname
? res0->ai_canonname
: saddr);
errorstr =
"Host address mismatch for %s\n";
hostname = naddr;
}
}
}
strlcpy(hostnamebuf, hostname, sizeof(hostnamebuf));
hostname = hostnamebuf;
if (res0)
freeaddrinfo(res0);
} else
strlcpy(hostnamebuf, naddr, sizeof(hostnamebuf));
errorhost = hostname = hostnamebuf;
#ifdef KERBEROS
if (use_kerberos) {
kdata = (AUTH_DAT *) authbuf;
ticket = (KTEXT) tickbuf;
authopts = 0L;
strlcpy(instance, "*", sizeof instance);
version[VERSION_SIZE - 1] = '\0';
#ifdef CRYPT
if (doencrypt) {
struct sockaddr_in local_addr;
rc = sizeof(local_addr);
if (getsockname(STDIN_FILENO,
(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, (struct sockaddr_in *)&fromaddr,
&local_addr, kdata, "", schedule, version);
desrw_set_key(&kdata->session, &schedule);
} else
#endif
rc = krb_recvauth(authopts, 0, ticket, "rcmd",
instance, (struct sockaddr_in *)&fromaddr,
NULL, kdata, "", NULL, version);
if (rc != KSUCCESS) {
error("Kerberos authentication failure: %s\n",
krb_get_err_text(rc));
exit(1);
}
} else
#endif
getstr(remuser, sizeof(remuser), "remuser");
getstr(locuser, sizeof(locuser), "locuser");
getstr(cmdbuf, sizeof(cmdbuf), "command");
pwd = getpwnam(locuser);
if (pwd == NULL) {
syslog(LOG_INFO|LOG_AUTH,
"%s@%s as %s: unknown login. cmd='%.80s'",
remuser, hostname, locuser, cmdbuf);
if (errorstr == NULL)
errorstr = "Permission denied.\n";
goto fail;
}
lc = login_getclass(pwd->pw_class);
if (lc == NULL) {
syslog(LOG_INFO|LOG_AUTH,
"%s@%s as %s: unknown class. cmd='%.80s'",
remuser, hostname, locuser, cmdbuf);
if (errorstr == NULL)
errorstr = "Login incorrect.\n";
goto fail;
}
as = auth_open();
if (as == NULL || auth_setpwd(as, pwd) != 0) {
syslog(LOG_INFO|LOG_AUTH,
"%s@%s as %s: unable to allocate memory. cmd='%.80s'",
remuser, hostname, locuser, cmdbuf);
if (errorstr == NULL)
errorstr = "Cannot allocate memory.\n";
goto fail;
}
setegid(pwd->pw_gid);
seteuid(pwd->pw_uid);
if (chdir(pwd->pw_dir) < 0) {
(void) chdir("/");
#ifdef notdef
syslog(LOG_INFO|LOG_AUTH,
"%s@%s as %s: no home directory. cmd='%.80s'",
remuser, hostname, locuser, cmdbuf);
error("No remote directory.\n");
exit(1);
#endif
}
seteuid(0);
setegid(0); /* XXX use a saved gid instead? */
#ifdef KERBEROS
if (use_kerberos) {
if (pwd->pw_passwd != 0 && *pwd->pw_passwd != '\0') {
if (kuserok(kdata, locuser) != 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
if (errorstr ||
(pwd->pw_passwd != 0 && *pwd->pw_passwd != '\0' &&
iruserok_sa(fromp, fromp->sa_len, pwd->pw_uid == 0,
remuser, locuser) < 0)) {
if (__rcmd_errstr)
syslog(LOG_INFO|LOG_AUTH,
"%s@%s as %s: permission denied (%s). cmd='%.80s'",
remuser, hostname, locuser, __rcmd_errstr,
cmdbuf);
else
syslog(LOG_INFO|LOG_AUTH,
"%s@%s as %s: permission denied. cmd='%.80s'",
remuser, hostname, locuser, cmdbuf);
fail:
if (errorstr == NULL)
errorstr = "Permission denied.\n";
error(errorstr, errorhost);
exit(1);
}
if (pwd->pw_uid)
auth_checknologin(lc);
(void) write(STDERR_FILENO, "\0", 1);
sent_null = 1;
if (port) {
if (pipe(pv) < 0) {
error("Can't make pipe.\n");
exit(1);
}
#ifdef CRYPT
#ifdef KERBEROS
if (doencrypt) {
if (pipe(pv1) < 0) {
error("Can't make 2nd pipe.\n");
exit(1);
}
if (pipe(pv2) < 0) {
error("Can't make 3rd pipe.\n");
exit(1);
}
}
#endif
#endif
pid = fork();
if (pid == -1) {
error("Can't fork; try again.\n");
exit(1);
}
if (pid) {
#ifdef CRYPT
#ifdef KERBEROS
if (doencrypt) {
static char msg[] = SECURE_MESSAGE;
(void) close(pv1[1]);
(void) close(pv2[1]);
des_write(s, msg, sizeof(msg) - 1);
} else
#endif
#endif
{
(void) close(STDIN_FILENO);
(void) close(STDOUT_FILENO);
}
(void) close(STDERR_FILENO);
(void) close(pv[1]);
pfd[P_SOCKREAD].fd = s;
pfd[P_SOCKREAD].events = POLLIN;
pfd[P_PIPEREAD].fd = pv[0];
pfd[P_PIPEREAD].events = POLLIN;
nfd = 2;
#ifdef CRYPT
#ifdef KERBEROS
if (doencrypt) {
pfd[P_CRYPTREAD].fd = pv1[0];
pfd[P_CRYPTREAD].events = POLLIN;
pfd[P_CRYPTWRITE].fd = pv2[0];
pfd[P_CRYPTWRITE].events = POLLOUT;
nfd += 2;
} else
#endif
#endif
ioctl(pv[0], FIONBIO, (char *)&one);
/* should set s nbio! */
do {
if (poll(pfd, nfd, INFTIM) < 0)
break;
if (pfd[P_SOCKREAD].revents & POLLIN) {
int ret;
#ifdef CRYPT
#ifdef KERBEROS
if (doencrypt)
ret = des_read(s, &sig, 1);
else
#endif
#endif
ret = read(s, &sig, 1);
if (ret <= 0)
pfd[P_SOCKREAD].revents = 0;
else
killpg(pid, sig);
}
if (pfd[P_PIPEREAD].revents & POLLIN) {
errno = 0;
cc = read(pv[0], buf, sizeof(buf));
if (cc <= 0) {
shutdown(s, SHUT_RDWR);
pfd[P_PIPEREAD].revents = 0;
} else {
#ifdef CRYPT
#ifdef KERBEROS
if (doencrypt)
(void)
des_write(s, buf, cc);
else
#endif
#endif
(void)
write(s, buf, cc);
}
}
#ifdef CRYPT
#ifdef KERBEROS
if (doencrypt &&
(pfd[P_CRYPTREAD].revents & POLLIN)) {
errno = 0;
cc = read(pv1[0], buf, sizeof(buf));
if (cc <= 0) {
shutdown(pv1[0], SHUT_RDWR);
pfd[P_CRYPTREAD].revents = 0;
} else
(void) des_write(STDOUT_FILENO,
buf, cc);
}
if (doencrypt &&
(pfd[P_CRYPTWRITE].revents & POLLIN)) {
errno = 0;
cc = des_read(STDIN_FILENO,
buf, sizeof(buf));
if (cc <= 0) {
shutdown(pv2[0], SHUT_RDWR);
pfd[P_CRYPTWRITE].revents = 0;
} else
(void) write(pv2[0], buf, cc);
}
#endif
#endif
} while ((pfd[P_SOCKREAD].revents & POLLIN) ||
#ifdef CRYPT
#ifdef KERBEROS
(doencrypt && (pfd[P_CRYPTREAD].revents & POLLIN)) ||
#endif
#endif
(pfd[P_PIPEREAD].revents & POLLIN));
exit(0);
}
setsid();
(void) close(s);
(void) close(pv[0]);
#ifdef CRYPT
#ifdef KERBEROS
if (doencrypt) {
close(pv1[0]); close(pv2[0]);
dup2(pv1[1], 1);
dup2(pv2[1], 0);
close(pv1[1]);
close(pv2[1]);
}
#endif
#endif
dup2(pv[1], 2);
close(pv[1]);
} else
setsid();
if (*pwd->pw_shell == '\0')
pwd->pw_shell = _PATH_BSHELL;
environ = envinit;
if (setenv("HOME", pwd->pw_dir, 1) == -1 ||
setenv("SHELL", pwd->pw_shell, 1) == -1 ||
setenv("USER", pwd->pw_name, 1) == -1 ||
setenv("LOGNAME", pwd->pw_name, 1) == -1)
errx(1, "cannot setup environment");
if (setusercontext(lc, pwd, pwd->pw_uid, LOGIN_SETALL))
errx(1, "cannot set user context");
if (auth_approval(as, lc, pwd->pw_name, "rsh") <= 0)
errx(1, "approval failure");
auth_close(as);
login_close(lc);
cp = strrchr(pwd->pw_shell, '/');
if (cp)
cp++;
else
cp = pwd->pw_shell;
endpwent();
if (log_success || pwd->pw_uid == 0) {
#ifdef 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, locuser, cmdbuf);
else
#endif
syslog(LOG_INFO|LOG_AUTH, "%s@%s as %s: cmd='%.80s'",
remuser, hostname, locuser, cmdbuf);
}
execl(pwd->pw_shell, cp, "-c", cmdbuf, (char *)NULL);
perror(pwd->pw_shell);
exit(1);
}
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;
login_cap_t *lc;
maxcmdlen = (int)sysconf(_SC_ARG_MAX);
if (maxcmdlen <= 0 || (cmdbuf = malloc(maxcmdlen)) == NULL)
exit(1);
(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 (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 (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);
}
}
errorstr = NULL;
realhostname_sa(rhost, sizeof(rhost) - 1, fromp, fromp->sa_len);
rhost[sizeof(rhost) - 1] = '\0';
/* XXX truncation! */
(void) alarm(60);
getstr(ruser, sizeof(ruser), "ruser");
getstr(luser, sizeof(luser), "luser");
getstr(cmdbuf, maxcmdlen, "command");
(void) alarm(0);
pam_err = pam_start("rsh", 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.");
}
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);
}
lc = login_getpwclass(pwd);
if (pwd->pw_uid)
auth_checknologin(lc);
if (chdir(pwd->pw_dir) < 0) {
if (chdir("/") < 0 ||
login_getcapbool(lc, "requirehome", !!pwd->pw_uid)) {
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.");
}
pwd->pw_dir = slash;
}
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);
}
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));
}
(void) write(STDERR_FILENO, "\0", 1);
sent_null = 1;
if (port) {
if (pipe(pv) < 0)
rshd_errx(1, "Can't make pipe.");
pid = fork();
if (pid == -1)
rshd_errx(1, "Can't fork; try again.");
if (pid) {
(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;
ioctl(pv[0], FIONBIO, (char *)&one);
/* should set s nbio! */
nfd++;
do {
ready = readfrom;
if (select(nfd, &ready, (fd_set *)0,
(fd_set *)0, (struct timeval *)0) < 0)
break;
if (FD_ISSET(s, &ready)) {
int ret;
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 {
(void)write(s, buf, cc);
}
}
} while (FD_ISSET(s, &readfrom) ||
FD_ISSET(pv[0], &readfrom));
PAM_END;
exit(0);
}
(void) close(s);
(void) close(pv[0]);
dup2(pv[1], 2);
close(pv[1]);
}
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);
}
}
for (fd = getdtablesize(); fd > 2; fd--)
(void) close(fd);
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;
(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);
cp = strrchr(pwd->pw_shell, '/');
if (cp)
cp++;
else
cp = pwd->pw_shell;
if (setusercontext(lc, pwd, pwd->pw_uid,
LOGIN_SETALL & ~LOGIN_SETGROUP) < 0) {
syslog(LOG_ERR, "setusercontext(): %m");
exit(1);
}
login_close(lc);
endpwent();
if (log_success || pwd->pw_uid == 0) {
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);
}
int
main(int argc, char *argv[])
{
char *domain, *p, *ttyn, *shell, *fullname, *instance;
char *lipaddr, *script, *ripaddr, *style, *type, *fqdn;
char tbuf[MAXPATHLEN + 2], tname[sizeof(_PATH_TTY) + 10];
char localhost[MAXHOSTNAMELEN], *copyright;
char mail[sizeof(_PATH_MAILDIR) + 1 + NAME_MAX];
int ask, ch, cnt, fflag, pflag, quietlog, rootlogin, lastchance;
int error, homeless, needto, authok, tries, backoff;
struct addrinfo *ai, hints;
struct rlimit cds, scds;
quad_t expire, warning;
struct utmp utmp;
struct group *gr;
struct stat st;
uid_t uid;
openlog("login", LOG_ODELAY, LOG_AUTH);
fqdn = lipaddr = ripaddr = fullname = type = NULL;
authok = 0;
tries = 10;
backoff = 3;
domain = NULL;
if (gethostname(localhost, sizeof(localhost)) < 0) {
syslog(LOG_ERR, "couldn't get local hostname: %m");
strlcpy(localhost, "localhost", sizeof(localhost));
} else if ((domain = strchr(localhost, '.'))) {
domain++;
if (*domain && strchr(domain, '.') == NULL)
domain = localhost;
}
if ((as = auth_open()) == NULL) {
syslog(LOG_ERR, "auth_open: %m");
err(1, "unable to initialize BSD authentication");
}
auth_setoption(as, "login", "yes");
/*
* -p is used by getty to tell login not to destroy the environment
* -f is used to skip a second login authentication
* -h is used by other servers to pass the name of the remote
* host to login so that it may be placed in utmp and wtmp
*/
fflag = pflag = 0;
uid = getuid();
while ((ch = getopt(argc, argv, "fh:pu:L:R:")) != -1)
switch (ch) {
case 'f':
fflag = 1;
break;
case 'h':
if (uid) {
warnc(EPERM, "-h option");
quickexit(1);
}
free(fqdn);
if ((fqdn = strdup(optarg)) == NULL) {
warn(NULL);
quickexit(1);
}
auth_setoption(as, "fqdn", fqdn);
if (domain && (p = strchr(optarg, '.')) &&
strcasecmp(p+1, domain) == 0)
*p = 0;
hostname = optarg;
auth_setoption(as, "hostname", hostname);
break;
case 'L':
if (uid) {
warnc(EPERM, "-L option");
quickexit(1);
}
if (lipaddr) {
warnx("duplicate -L option");
quickexit(1);
}
lipaddr = optarg;
memset(&hints, 0, sizeof(hints));
hints.ai_family = PF_UNSPEC;
hints.ai_flags = AI_CANONNAME;
error = getaddrinfo(lipaddr, NULL, &hints, &ai);
if (!error) {
strlcpy(localhost, ai->ai_canonname,
sizeof(localhost));
freeaddrinfo(ai);
} else
strlcpy(localhost, lipaddr, sizeof(localhost));
auth_setoption(as, "local_addr", lipaddr);
break;
case 'p':
pflag = 1;
break;
case 'R':
if (uid) {
warnc(EPERM, "-R option");
quickexit(1);
}
if (ripaddr) {
warnx("duplicate -R option");
quickexit(1);
}
ripaddr = optarg;
auth_setoption(as, "remote_addr", ripaddr);
break;
case 'u':
if (uid) {
warnc(EPERM, "-u option");
quickexit(1);
}
rusername = optarg;
break;
default:
if (!uid)
syslog(LOG_ERR, "invalid flag %c", ch);
(void)fprintf(stderr,
"usage: login [-fp] [-h hostname] [-L local-addr] "
"[-R remote-addr] [-u username]\n\t[user]\n");
quickexit(1);
}
argc -= optind;
argv += optind;
if (*argv) {
username = *argv;
ask = 0;
} else
ask = 1;
/*
* If effective user is not root, just run su(1) to emulate login(1).
*/
if (geteuid() != 0) {
char *av[5], **ap;
auth_close(as);
closelog();
closefrom(STDERR_FILENO + 1);
ap = av;
*ap++ = _PATH_SU;
*ap++ = "-L";
if (!pflag)
*ap++ = "-l";
if (!ask)
*ap++ = username;
*ap = NULL;
execv(_PATH_SU, av);
warn("unable to exec %s", _PATH_SU);
_exit(1);
}
ttyn = ttyname(STDIN_FILENO);
if (ttyn == NULL || *ttyn == '\0') {
(void)snprintf(tname, sizeof(tname), "%s??", _PATH_TTY);
ttyn = tname;
}
if ((tty = strrchr(ttyn, '/')))
++tty;
else
tty = ttyn;
/*
* Since login deals with sensitive information, turn off coredumps.
*/
if (getrlimit(RLIMIT_CORE, &scds) < 0) {
syslog(LOG_ERR, "couldn't get core dump size: %m");
scds.rlim_cur = scds.rlim_max = QUAD_MIN;
}
cds.rlim_cur = cds.rlim_max = 0;
if (setrlimit(RLIMIT_CORE, &cds) < 0) {
syslog(LOG_ERR, "couldn't set core dump size to 0: %m");
scds.rlim_cur = scds.rlim_max = QUAD_MIN;
}
(void)signal(SIGALRM, timedout);
if (argc > 1) {
needto = 0;
(void)alarm(timeout);
} else
needto = 1;
(void)signal(SIGQUIT, SIG_IGN);
(void)signal(SIGINT, SIG_IGN);
(void)signal(SIGHUP, SIG_IGN);
(void)setpriority(PRIO_PROCESS, 0, 0);
#ifdef notyet
/* XXX - we don't (yet) support per-tty auth stuff */
/* BSDi uses a ttys.conf file but we could just overload /etc/ttys */
/*
* Classify the attempt.
* By default we use the value in the ttys file.
* If there is a classify script we run that as
*
* classify [-f] [username]
*/
if (type = getttyauth(tty))
auth_setoption(as, "auth_type", type);
#endif
/* get the default login class */
if ((lc = login_getclass(0)) == NULL) { /* get the default class */
warnx("Failure to retrieve default class");
quickexit(1);
}
timeout = (u_int)login_getcapnum(lc, "login-timeout", 300, 300);
if ((script = login_getcapstr(lc, "classify", NULL, NULL)) != NULL) {
unsetenv("AUTH_TYPE");
unsetenv("REMOTE_NAME");
if (script[0] != '/') {
syslog(LOG_ERR, "Invalid classify script: %s", script);
warnx("Classification failure");
quickexit(1);
}
shell = strrchr(script, '/') + 1;
auth_setstate(as, AUTH_OKAY);
auth_call(as, script, shell,
fflag ? "-f" : username, fflag ? username : 0, (char *)0);
if (!(auth_getstate(as) & AUTH_ALLOW))
quickexit(1);
auth_setenv(as);
if ((p = getenv("AUTH_TYPE")) != NULL &&
strncmp(p, "auth-", 5) == 0)
type = p;
if ((p = getenv("REMOTE_NAME")) != NULL)
hostname = p;
/*
* we may have changed some values, reset them
*/
auth_clroptions(as);
if (type)
auth_setoption(as, "auth_type", type);
if (fqdn)
auth_setoption(as, "fqdn", fqdn);
if (hostname)
auth_setoption(as, "hostname", hostname);
if (lipaddr)
auth_setoption(as, "local_addr", lipaddr);
if (ripaddr)
auth_setoption(as, "remote_addr", ripaddr);
}
/*
* Request the things like the approval script print things
* to stdout (in particular, the nologins files)
*/
auth_setitem(as, AUTHV_INTERACTIVE, "True");
for (cnt = 0;; ask = 1) {
/*
* Clean up our current authentication session.
* Options are not cleared so we need to clear any
* we might set below.
*/
auth_clean(as);
auth_clroption(as, "style");
auth_clroption(as, "lastchance");
lastchance = 0;
if (ask) {
fflag = 0;
getloginname();
}
if (needto) {
needto = 0;
alarm(timeout);
}
if ((style = strchr(username, ':')) != NULL)
*style++ = '\0';
if (fullname)
free(fullname);
if (auth_setitem(as, AUTHV_NAME, username) < 0 ||
(fullname = strdup(username)) == NULL) {
syslog(LOG_ERR, "%m");
warn(NULL);
quickexit(1);
}
rootlogin = 0;
if ((instance = strchr(username, '/')) != NULL) {
if (strncmp(instance + 1, "root", 4) == 0)
rootlogin = 1;
*instance++ = '\0';
} else
instance = "";
if (strlen(username) > UT_NAMESIZE)
username[UT_NAMESIZE] = '\0';
/*
* Note if trying multiple user names; log failures for
* previous user name, but don't bother logging one failure
* for nonexistent name (mistyped username).
*/
if (failures && strcmp(tbuf, username)) {
if (failures > (pwd ? 0 : 1))
badlogin(tbuf);
failures = 0;
}
(void)strlcpy(tbuf, username, sizeof(tbuf));
if ((pwd = getpwnam(username)) != NULL &&
auth_setpwd(as, pwd) < 0) {
syslog(LOG_ERR, "%m");
warn(NULL);
quickexit(1);
}
lc = login_getclass(pwd ? pwd->pw_class : NULL);
if (!lc)
goto failed;
style = login_getstyle(lc, style, type);
if (!style)
goto failed;
/*
* We allow "login-tries" attempts to login but start
* slowing down after "login-backoff" attempts.
*/
tries = (int)login_getcapnum(lc, "login-tries", 10, 10);
backoff = (int)login_getcapnum(lc, "login-backoff", 3, 3);
/*
* Turn off the fflag if we have an invalid user
* or we are not root and we are trying to change uids.
*/
if (!pwd || (uid && uid != pwd->pw_uid))
fflag = 0;
if (pwd && pwd->pw_uid == 0)
rootlogin = 1;
/*
* If we do not have the force flag authenticate the user
*/
if (!fflag) {
lastchance =
login_getcaptime(lc, "password-dead", 0, 0) != 0;
if (lastchance)
auth_setoption(as, "lastchance", "yes");
/*
* Once we start asking for a password
* we want to log a failure on a hup.
*/
signal(SIGHUP, sighup);
auth_verify(as, style, NULL, lc->lc_class, NULL);
authok = auth_getstate(as);
/*
* If their password expired and it has not been
* too long since then, give the user one last
* chance to change their password
*/
if ((authok & AUTH_PWEXPIRED) && lastchance) {
authok = AUTH_OKAY;
} else
lastchance = 0;
if ((authok & AUTH_ALLOW) == 0)
goto failed;
if (auth_setoption(as, "style", style) < 0) {
syslog(LOG_ERR, "%m");
warn(NULL);
quickexit(1);
}
}
/*
* explicitly reject users without password file entries
*/
if (pwd == NULL)
goto failed;
/*
* If trying to log in as root on an insecure terminal,
* refuse the login attempt unless the authentication
* style explicitly says a root login is okay.
*/
if (pwd && rootlogin && !rootterm(tty))
goto failed;
if (fflag) {
type = 0;
style = "forced";
}
break;
failed:
if (authok & AUTH_SILENT)
quickexit(0);
if (rootlogin && !rootterm(tty)) {
warnx("%s login refused on this terminal.",
fullname);
if (hostname)
syslog(LOG_NOTICE,
"LOGIN %s REFUSED FROM %s%s%s ON TTY %s",
fullname, rusername ? rusername : "",
rusername ? "@" : "", hostname, tty);
else
syslog(LOG_NOTICE,
"LOGIN %s REFUSED ON TTY %s",
fullname, tty);
} else {
if (!as || (p = auth_getvalue(as, "errormsg")) == NULL)
p = "Login incorrect";
(void)printf("%s\n", p);
}
failures++;
if (pwd)
log_failedlogin(pwd->pw_uid, hostname, rusername, tty);
/*
* By default, we allow 10 tries, but after 3 we start
* backing off to slow down password guessers.
*/
if (++cnt > backoff) {
if (cnt >= tries) {
badlogin(username);
sleepexit(1);
}
sleep((u_int)((cnt - backoff) * tries / 2));
}
}
/* committed to login -- turn off timeout */
(void)alarm(0);
endpwent();
shell = login_getcapstr(lc, "shell", pwd->pw_shell, pwd->pw_shell);
if (*shell == '\0')
shell = _PATH_BSHELL;
else if (strlen(shell) >= MAXPATHLEN) {
syslog(LOG_ERR, "shell path too long: %s", shell);
warnx("invalid shell");
quickexit(1);
}
/* Destroy environment unless user has requested its preservation. */
if (!pflag) {
if ((environ = calloc(1, sizeof (char *))) == NULL)
err(1, "calloc");
} else {
char **cpp, **cpp2;
for (cpp2 = cpp = environ; *cpp; cpp++) {
if (strncmp(*cpp, "LD_", 3) &&
strncmp(*cpp, "ENV=", 4) &&
strncmp(*cpp, "BASH_ENV=", 9) &&
strncmp(*cpp, "IFS=", 4))
*cpp2++ = *cpp;
}
*cpp2 = 0;
}
/* Note: setusercontext(3) will set PATH */
if (setenv("HOME", pwd->pw_dir, 1) == -1 ||
setenv("SHELL", pwd->pw_shell, 1) == -1) {
warn("unable to setenv()");
quickexit(1);
}
if (term[0] == '\0')
(void)strlcpy(term, stypeof(tty), sizeof(term));
(void)snprintf(mail, sizeof(mail), "%s/%s", _PATH_MAILDIR,
pwd->pw_name);
if (setenv("TERM", term, 0) == -1 ||
setenv("LOGNAME", pwd->pw_name, 1) == -1 ||
setenv("USER", pwd->pw_name, 1) == -1 ||
setenv("MAIL", mail, 1) == -1) {
warn("unable to setenv()");
quickexit(1);
}
if (hostname) {
if (setenv("REMOTEHOST", hostname, 1) == -1) {
warn("unable to setenv()");
quickexit(1);
}
}
if (rusername) {
if (setenv("REMOTEUSER", rusername, 1) == -1) {
warn("unable to setenv()");
quickexit(1);
}
}
if (setusercontext(lc, pwd, pwd->pw_uid, LOGIN_SETPATH)) {
warn("unable to set user context");
quickexit(1);
}
auth_setenv(as);
/* if user not super-user, check for disabled logins */
if (!rootlogin)
auth_checknologin(lc);
setegid(pwd->pw_gid);
seteuid(pwd->pw_uid);
homeless = chdir(pwd->pw_dir);
if (homeless) {
if (login_getcapbool(lc, "requirehome", 0)) {
(void)printf("No home directory %s!\n", pwd->pw_dir);
quickexit(1);
}
if (chdir("/"))
quickexit(0);
}
quietlog = ((strcmp(pwd->pw_shell, "/sbin/nologin") == 0) ||
login_getcapbool(lc, "hushlogin", 0) ||
(access(_PATH_HUSHLOGIN, F_OK) == 0));
seteuid(0);
setegid(0); /* XXX use a saved gid instead? */
if ((p = auth_getvalue(as, "warnmsg")) != NULL)
(void)printf("WARNING: %s\n\n", p);
expire = auth_check_expire(as);
if (expire < 0) {
(void)printf("Sorry -- your account has expired.\n");
quickexit(1);
} else if (expire > 0 && !quietlog) {
warning = login_getcaptime(lc, "expire-warn",
2 * DAYSPERWEEK * SECSPERDAY, 2 * DAYSPERWEEK * SECSPERDAY);
if (expire < warning)
(void)printf("Warning: your account expires on %s",
ctime(&pwd->pw_expire));
}
/* Nothing else left to fail -- really log in. */
(void)signal(SIGHUP, SIG_DFL);
memset(&utmp, 0, sizeof(utmp));
(void)time(&utmp.ut_time);
(void)strncpy(utmp.ut_name, username, sizeof(utmp.ut_name));
if (hostname)
(void)strncpy(utmp.ut_host, hostname, sizeof(utmp.ut_host));
(void)strncpy(utmp.ut_line, tty, sizeof(utmp.ut_line));
login(&utmp);
if (!quietlog)
(void)check_failedlogin(pwd->pw_uid);
dolastlog(quietlog);
login_fbtab(tty, pwd->pw_uid, pwd->pw_gid);
(void)chown(ttyn, pwd->pw_uid,
(gr = getgrnam(TTYGRPNAME)) ? gr->gr_gid : pwd->pw_gid);
/* If fflag is on, assume caller/authenticator has logged root login. */
if (rootlogin && fflag == 0) {
if (hostname)
syslog(LOG_NOTICE, "ROOT LOGIN (%s) ON %s FROM %s%s%s",
username, tty, rusername ? rusername : "",
rusername ? "@" : "", hostname);
else
syslog(LOG_NOTICE, "ROOT LOGIN (%s) ON %s", username, tty);
}
if (!quietlog) {
if ((copyright =
login_getcapstr(lc, "copyright", NULL, NULL)) != NULL)
auth_cat(copyright);
motd();
if (stat(mail, &st) == 0 && st.st_size != 0)
(void)printf("You have %smail.\n",
(st.st_mtime > st.st_atime) ? "new " : "");
}
(void)signal(SIGALRM, SIG_DFL);
(void)signal(SIGQUIT, SIG_DFL);
(void)signal(SIGHUP, SIG_DFL);
(void)signal(SIGINT, SIG_DFL);
(void)signal(SIGTSTP, SIG_IGN);
tbuf[0] = '-';
(void)strlcpy(tbuf + 1, (p = strrchr(shell, '/')) ?
p + 1 : shell, sizeof(tbuf) - 1);
if ((scds.rlim_cur != QUAD_MIN || scds.rlim_max != QUAD_MIN) &&
setrlimit(RLIMIT_CORE, &scds) < 0)
syslog(LOG_ERR, "couldn't reset core dump size: %m");
if (lastchance)
(void)printf("WARNING: Your password has expired."
" You must change your password, now!\n");
if (setusercontext(lc, pwd, rootlogin ? 0 : pwd->pw_uid,
LOGIN_SETALL & ~LOGIN_SETPATH) < 0) {
warn("unable to set user context");
quickexit(1);
}
if (homeless) {
(void)printf("No home directory %s!\n", pwd->pw_dir);
(void)printf("Logging in with home = \"/\".\n");
(void)setenv("HOME", "/", 1);
}
if (auth_approval(as, lc, NULL, "login") == 0) {
if (auth_getstate(as) & AUTH_EXPIRED)
(void)printf("Sorry -- your account has expired.\n");
else
(void)printf("approval failure\n");
quickexit(1);
}
/*
* The last thing we do is discard all of the open file descriptors.
* Last because the C library may have some open.
*/
closefrom(STDERR_FILENO + 1);
/*
* Close the authentication session, make sure it is marked
* as okay so no files are removed.
*/
auth_setstate(as, AUTH_OKAY);
auth_close(as);
execlp(shell, tbuf, (char *)NULL);
err(1, "%s", shell);
}
