/
inetd.c
2498 lines (2359 loc) · 61.6 KB
/
inetd.c
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/*
* Copyright (c) 1983, 1991, 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.
*
* @(#) Copyright (c) 1983, 1991, 1993, 1994 The Regents of the University of California. All rights reserved.
* @(#)from: inetd.c 8.4 (Berkeley) 4/13/94
* $FreeBSD: src/usr.sbin/inetd/inetd.c,v 1.80.2.11 2003/04/05 13:39:18 dwmalone Exp $
* $DragonFly: src/usr.sbin/inetd/inetd.c,v 1.11 2008/05/23 23:40:59 swildner Exp $
*/
/*
* Inetd - Internet super-server
*
* This program invokes all internet services as needed. Connection-oriented
* services are invoked each time a connection is made, by creating a process.
* This process is passed the connection as file descriptor 0 and is expected
* to do a getpeername to find out the source host and port.
*
* Datagram oriented services are invoked when a datagram
* arrives; a process is created and passed a pending message
* on file descriptor 0. Datagram servers may either connect
* to their peer, freeing up the original socket for inetd
* to receive further messages on, or ``take over the socket'',
* processing all arriving datagrams and, eventually, timing
* out. The first type of server is said to be ``multi-threaded'';
* the second type of server ``single-threaded''.
*
* Inetd uses a configuration file which is read at startup
* and, possibly, at some later time in response to a hangup signal.
* The configuration file is ``free format'' with fields given in the
* order shown below. Continuation lines for an entry must begin with
* a space or tab. All fields must be present in each entry.
*
* service name must be in /etc/services
* or name a tcpmux service
* or specify a unix domain socket
* socket type stream/dgram/raw/rdm/seqpacket
* protocol tcp[4][6][/faith,ttcp], udp[4][6], unix
* wait/nowait single-threaded/multi-threaded
* user user to run daemon as
* server program full path name
* server program arguments maximum of MAXARGS (20)
*
* TCP services without official port numbers are handled with the
* RFC1078-based tcpmux internal service. Tcpmux listens on port 1 for
* requests. When a connection is made from a foreign host, the service
* requested is passed to tcpmux, which looks it up in the servtab list
* and returns the proper entry for the service. Tcpmux returns a
* negative reply if the service doesn't exist, otherwise the invoked
* server is expected to return the positive reply if the service type in
* inetd.conf file has the prefix "tcpmux/". If the service type has the
* prefix "tcpmux/+", tcpmux will return the positive reply for the
* process; this is for compatibility with older server code, and also
* allows you to invoke programs that use stdin/stdout without putting any
* special server code in them. Services that use tcpmux are "nowait"
* because they do not have a well-known port and hence cannot listen
* for new requests.
*
* For RPC services
* service name/version must be in /etc/rpc
* socket type stream/dgram/raw/rdm/seqpacket
* protocol rpc/tcp, rpc/udp
* wait/nowait single-threaded/multi-threaded
* user user to run daemon as
* server program full path name
* server program arguments maximum of MAXARGS
*
* Comment lines are indicated by a `#' in column 1.
*
* #ifdef IPSEC
* Comment lines that start with "#@" denote IPsec policy string, as described
* in ipsec_set_policy(3). This will affect all the following items in
* inetd.conf(8). To reset the policy, just use "#@" line. By default,
* there's no IPsec policy.
* #endif
*/
#include <sys/param.h>
#include <sys/ioctl.h>
#include <sys/wait.h>
#include <sys/time.h>
#include <sys/resource.h>
#include <sys/stat.h>
#include <sys/un.h>
#include <netinet/in.h>
#include <netinet/tcp.h>
#include <arpa/inet.h>
#include <rpc/rpc.h>
#include <rpc/pmap_clnt.h>
#include <errno.h>
#include <err.h>
#include <fcntl.h>
#include <grp.h>
#include <limits.h>
#include <netdb.h>
#include <pwd.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <syslog.h>
#include <tcpd.h>
#include <unistd.h>
#include <libutil.h>
#include <sysexits.h>
#include <ctype.h>
#include "inetd.h"
#include "pathnames.h"
#ifdef IPSEC
#include <netinet6/ipsec.h>
#ifndef IPSEC_POLICY_IPSEC /* no ipsec support on old ipsec */
#undef IPSEC
#endif
#endif
/* wrapper for KAME-special getnameinfo() */
#ifndef NI_WITHSCOPEID
#define NI_WITHSCOPEID 0
#endif
#ifndef LIBWRAP_ALLOW_FACILITY
# define LIBWRAP_ALLOW_FACILITY LOG_AUTH
#endif
#ifndef LIBWRAP_ALLOW_SEVERITY
# define LIBWRAP_ALLOW_SEVERITY LOG_INFO
#endif
#ifndef LIBWRAP_DENY_FACILITY
# define LIBWRAP_DENY_FACILITY LOG_AUTH
#endif
#ifndef LIBWRAP_DENY_SEVERITY
# define LIBWRAP_DENY_SEVERITY LOG_WARNING
#endif
#define ISWRAP(sep) \
( ((wrap_ex && !(sep)->se_bi) || (wrap_bi && (sep)->se_bi)) \
&& (sep->se_family == AF_INET || sep->se_family == AF_INET6) \
&& ( ((sep)->se_accept && (sep)->se_socktype == SOCK_STREAM) \
|| (sep)->se_socktype == SOCK_DGRAM))
#ifdef LOGIN_CAP
#include <login_cap.h>
/* see init.c */
#define RESOURCE_RC "daemon"
#endif
#ifndef MAXCHILD
#define MAXCHILD -1 /* maximum number of this service
< 0 = no limit */
#endif
#ifndef MAXCPM
#define MAXCPM -1 /* rate limit invocations from a
single remote address,
< 0 = no limit */
#endif
#ifndef MAXPERIP
#define MAXPERIP -1 /* maximum number of this service
from a single remote address,
< 0 = no limit */
#endif
#ifndef TOOMANY
#define TOOMANY 256 /* don't start more than TOOMANY */
#endif
#define CNT_INTVL 60 /* servers in CNT_INTVL sec. */
#define RETRYTIME (60*10) /* retry after bind or server fail */
#define MAX_MAXCHLD 32767 /* max allowable max children */
#define SIGBLOCK (sigmask(SIGCHLD)|sigmask(SIGHUP)|sigmask(SIGALRM))
void close_sep(struct servtab *);
void flag_signal(int);
void flag_config(int);
void config(void);
int cpmip(const struct servtab *, int);
void endconfig(void);
struct servtab *enter(struct servtab *);
void freeconfig(struct servtab *);
struct servtab *getconfigent(void);
int matchservent(const char *, const char *, const char *);
char *nextline(FILE *);
void addchild(struct servtab *, int);
void flag_reapchild(int);
void reapchild(void);
void enable(struct servtab *);
void disable(struct servtab *);
void flag_retry(int);
void retry(void);
int setconfig(void);
void setup(struct servtab *);
#ifdef IPSEC
void ipsecsetup(struct servtab *);
#endif
void unregisterrpc(struct servtab *sep);
static struct conninfo *search_conn(struct servtab *sep, int ctrl);
static int room_conn(struct servtab *sep, struct conninfo *conn);
static void addchild_conn(struct conninfo *conn, pid_t pid);
static void reapchild_conn(pid_t pid);
static void free_conn(struct conninfo *conn);
static void resize_conn(struct servtab *sep, int maxperip);
static void free_connlist(struct servtab *sep);
static void free_proc(struct procinfo *);
static struct procinfo *search_proc(pid_t pid, int add);
static int hashval(char *p, int len);
int allow_severity;
int deny_severity;
int wrap_ex = 0;
int wrap_bi = 0;
int debug = 0;
int dolog = 0;
int maxsock; /* highest-numbered descriptor */
fd_set allsock;
int options;
int timingout;
int toomany = TOOMANY;
int maxchild = MAXCHILD;
int maxcpm = MAXCPM;
int maxperip = MAXPERIP;
struct servent *sp;
struct rpcent *rpc;
char *hostname = NULL;
struct sockaddr_in *bind_sa4;
int no_v4bind = 1;
#ifdef INET6
struct sockaddr_in6 *bind_sa6;
int no_v6bind = 1;
#endif
int signalpipe[2];
#ifdef SANITY_CHECK
int nsock;
#endif
uid_t euid;
gid_t egid;
mode_t mask;
struct servtab *servtab;
extern struct biltin biltins[];
#define NUMINT (sizeof(intab) / sizeof(struct inent))
const char *CONFIG = _PATH_INETDCONF;
const char *pid_file = _PATH_INETDPID;
static LIST_HEAD(, procinfo) proctable[PERIPSIZE];
int
getvalue(const char *arg, int *value, const char *whine)
{
int tmp;
char *p;
tmp = strtol(arg, &p, 0);
if (tmp < 0 || *p) {
syslog(LOG_ERR, whine, arg);
return 1; /* failure */
}
*value = tmp;
return 0; /* success */
}
static sa_family_t
whichaf(struct request_info *req)
{
struct sockaddr *sa;
sa = (struct sockaddr *)req->client->sin;
if (sa == NULL)
return AF_UNSPEC;
if (sa->sa_family == AF_INET6 &&
IN6_IS_ADDR_V4MAPPED(&((struct sockaddr_in6 *)sa)->sin6_addr))
return AF_INET;
return sa->sa_family;
}
int
main(int argc, char **argv)
{
struct servtab *sep;
struct passwd *pwd;
struct group *grp;
struct sigaction sa, saalrm, sachld, sahup, sapipe;
int ch, dofork;
pid_t pid;
char buf[50];
#ifdef LOGIN_CAP
login_cap_t *lc = NULL;
#endif
struct request_info req;
int denied;
char *service = NULL;
union {
struct sockaddr peer_un;
struct sockaddr_in peer_un4;
struct sockaddr_in6 peer_un6;
struct sockaddr_storage peer_max;
} p_un;
#define peer p_un.peer_un
#define peer4 p_un.peer_un4
#define peer6 p_un.peer_un6
#define peermax p_un.peer_max
int i;
struct addrinfo hints, *res;
const char *servname;
int error;
struct conninfo *conn;
openlog("inetd", LOG_PID | LOG_NOWAIT | LOG_PERROR, LOG_DAEMON);
while ((ch = getopt(argc, argv, "dlwWR:a:c:C:p:s:")) != -1)
switch(ch) {
case 'd':
debug = 1;
options |= SO_DEBUG;
break;
case 'l':
dolog = 1;
break;
case 'R':
getvalue(optarg, &toomany,
"-R %s: bad value for service invocation rate");
break;
case 'c':
getvalue(optarg, &maxchild,
"-c %s: bad value for maximum children");
break;
case 'C':
getvalue(optarg, &maxcpm,
"-C %s: bad value for maximum children/minute");
break;
case 'a':
hostname = optarg;
break;
case 'p':
pid_file = optarg;
break;
case 's':
getvalue(optarg, &maxperip,
"-s %s: bad value for maximum children per source address");
break;
case 'w':
wrap_ex++;
break;
case 'W':
wrap_bi++;
break;
case '?':
default:
syslog(LOG_ERR,
"usage: inetd [-dlwW] [-a address] [-R rate]"
" [-c maximum] [-C rate]"
" [-p pidfile] [conf-file]");
exit(EX_USAGE);
}
/*
* Initialize Bind Addrs.
* When hostname is NULL, wild card bind addrs are obtained from
* getaddrinfo(). But getaddrinfo() requires at least one of
* hostname or servname is non NULL.
* So when hostname is NULL, set dummy value to servname.
*/
servname = (hostname == NULL) ? "discard" /* dummy */ : NULL;
bzero(&hints, sizeof(struct addrinfo));
hints.ai_flags = AI_PASSIVE;
hints.ai_family = AF_UNSPEC;
error = getaddrinfo(hostname, servname, &hints, &res);
if (error != 0) {
syslog(LOG_ERR, "-a %s: %s", hostname, gai_strerror(error));
if (error == EAI_SYSTEM)
syslog(LOG_ERR, "%s", strerror(errno));
exit(EX_USAGE);
}
do {
if (res->ai_addr == NULL) {
syslog(LOG_ERR, "-a %s: getaddrinfo failed", hostname);
exit(EX_USAGE);
}
switch (res->ai_addr->sa_family) {
case AF_INET:
if (no_v4bind == 0)
continue;
bind_sa4 = (struct sockaddr_in *)res->ai_addr;
/* init port num in case servname is dummy */
bind_sa4->sin_port = 0;
no_v4bind = 0;
continue;
#ifdef INET6
case AF_INET6:
if (no_v6bind == 0)
continue;
bind_sa6 = (struct sockaddr_in6 *)res->ai_addr;
/* init port num in case servname is dummy */
bind_sa6->sin6_port = 0;
no_v6bind = 0;
continue;
#endif
}
if (no_v4bind == 0
#ifdef INET6
&& no_v6bind == 0
#endif
)
break;
} while ((res = res->ai_next) != NULL);
if (no_v4bind != 0
#ifdef INET6
&& no_v6bind != 0
#endif
) {
syslog(LOG_ERR, "-a %s: unknown address family", hostname);
exit(EX_USAGE);
}
euid = geteuid();
egid = getegid();
umask(mask = umask(0777));
argc -= optind;
argv += optind;
if (argc > 0)
CONFIG = argv[0];
if (debug == 0) {
FILE *fp;
if (daemon(0, 0) < 0) {
syslog(LOG_WARNING, "daemon(0,0) failed: %m");
}
/* From now on we don't want syslog messages going to stderr. */
closelog();
openlog("inetd", LOG_PID | LOG_NOWAIT, LOG_DAEMON);
/*
* In case somebody has started inetd manually, we need to
* clear the logname, so that old servers run as root do not
* get the user's logname..
*/
if (setlogin("") < 0) {
syslog(LOG_WARNING, "cannot clear logname: %m");
/* no big deal if it fails.. */
}
pid = getpid();
fp = fopen(pid_file, "w");
if (fp) {
fprintf(fp, "%ld\n", (long)pid);
fclose(fp);
} else {
syslog(LOG_WARNING, "%s: %m", pid_file);
}
}
for (i = 0; i < PERIPSIZE; ++i)
LIST_INIT(&proctable[i]);
sa.sa_flags = 0;
sigemptyset(&sa.sa_mask);
sigaddset(&sa.sa_mask, SIGALRM);
sigaddset(&sa.sa_mask, SIGCHLD);
sigaddset(&sa.sa_mask, SIGHUP);
sa.sa_handler = flag_retry;
sigaction(SIGALRM, &sa, &saalrm);
config();
sa.sa_handler = flag_config;
sigaction(SIGHUP, &sa, &sahup);
sa.sa_handler = flag_reapchild;
sigaction(SIGCHLD, &sa, &sachld);
sa.sa_handler = SIG_IGN;
sigaction(SIGPIPE, &sa, &sapipe);
{
/* space for daemons to overwrite environment for ps */
#define DUMMYSIZE 100
char dummy[DUMMYSIZE];
memset(dummy, 'x', DUMMYSIZE - 1);
dummy[DUMMYSIZE - 1] = '\0';
if (setenv("inetd_dummy", dummy, 1) == -1)
syslog(LOG_WARNING, "setenv: cannot set inetd_dummy=%s: %m", dummy);
}
if (pipe(signalpipe) != 0) {
syslog(LOG_ERR, "pipe: %m");
exit(EX_OSERR);
}
if (fcntl(signalpipe[0], F_SETFD, FD_CLOEXEC) < 0 ||
fcntl(signalpipe[1], F_SETFD, FD_CLOEXEC) < 0) {
syslog(LOG_ERR, "signalpipe: fcntl (F_SETFD, FD_CLOEXEC): %m");
exit(EX_OSERR);
}
FD_SET(signalpipe[0], &allsock);
#ifdef SANITY_CHECK
nsock++;
#endif
if (signalpipe[0] > maxsock)
maxsock = signalpipe[0];
if (signalpipe[1] > maxsock)
maxsock = signalpipe[1];
for (;;) {
int n, ctrl;
fd_set readable;
#ifdef SANITY_CHECK
if (nsock == 0) {
syslog(LOG_ERR, "%s: nsock=0", __func__);
exit(EX_SOFTWARE);
}
#endif
readable = allsock;
if ((n = select(maxsock + 1, &readable, NULL, NULL, NULL)) <= 0) {
if (n < 0 && errno != EINTR) {
syslog(LOG_WARNING, "select: %m");
sleep(1);
}
continue;
}
/* handle any queued signal flags */
if (FD_ISSET(signalpipe[0], &readable)) {
int nsig;
if (ioctl(signalpipe[0], FIONREAD, &nsig) != 0) {
syslog(LOG_ERR, "ioctl: %m");
exit(EX_OSERR);
}
while (--nsig >= 0) {
char c;
if (read(signalpipe[0], &c, 1) != 1) {
syslog(LOG_ERR, "read: %m");
exit(EX_OSERR);
}
if (debug)
warnx("handling signal flag %c", c);
switch(c) {
case 'A': /* sigalrm */
retry();
break;
case 'C': /* sigchld */
reapchild();
break;
case 'H': /* sighup */
config();
break;
}
}
}
for (sep = servtab; n && sep; sep = sep->se_next)
if (sep->se_fd != -1 && FD_ISSET(sep->se_fd, &readable)) {
n--;
if (debug)
warnx("someone wants %s", sep->se_service);
dofork = !sep->se_bi || sep->se_bi->bi_fork || ISWRAP(sep);
conn = NULL;
if (sep->se_accept && sep->se_socktype == SOCK_STREAM) {
i = 1;
if (ioctl(sep->se_fd, FIONBIO, &i) < 0)
syslog(LOG_ERR, "ioctl (FIONBIO, 1): %m");
ctrl = accept(sep->se_fd, NULL, NULL);
if (debug)
warnx("accept, ctrl %d", ctrl);
if (ctrl < 0) {
if (errno != EINTR)
syslog(LOG_WARNING,
"accept (for %s): %m",
sep->se_service);
if (sep->se_accept &&
sep->se_socktype == SOCK_STREAM)
close(ctrl);
continue;
}
i = 0;
if (ioctl(sep->se_fd, FIONBIO, &i) < 0)
syslog(LOG_ERR, "ioctl1(FIONBIO, 0): %m");
if (ioctl(ctrl, FIONBIO, &i) < 0)
syslog(LOG_ERR, "ioctl2(FIONBIO, 0): %m");
if (cpmip(sep, ctrl) < 0) {
close(ctrl);
continue;
}
if (dofork &&
(conn = search_conn(sep, ctrl)) != NULL &&
!room_conn(sep, conn)) {
close(ctrl);
continue;
}
} else
ctrl = sep->se_fd;
if (dolog && !ISWRAP(sep)) {
char pname[INET6_ADDRSTRLEN] = "unknown";
socklen_t sl;
sl = sizeof peermax;
if (getpeername(ctrl, (struct sockaddr *)
&peermax, &sl)) {
sl = sizeof peermax;
if (recvfrom(ctrl, buf, sizeof(buf),
MSG_PEEK,
(struct sockaddr *)&peermax,
&sl) >= 0) {
getnameinfo((struct sockaddr *)&peermax,
peer.sa_len,
pname, sizeof(pname),
NULL, 0,
NI_NUMERICHOST|
NI_WITHSCOPEID);
}
} else {
getnameinfo((struct sockaddr *)&peermax,
peer.sa_len,
pname, sizeof(pname),
NULL, 0,
NI_NUMERICHOST|
NI_WITHSCOPEID);
}
syslog(LOG_INFO,"%s from %s", sep->se_service, pname);
}
sigblock(SIGBLOCK);
pid = 0;
/*
* Fork for all external services, builtins which need to
* fork and anything we're wrapping (as wrapping might
* block or use hosts_options(5) twist).
*/
if (dofork) {
if (sep->se_count++ == 0)
gettimeofday(&sep->se_time, NULL);
else if (toomany > 0 && sep->se_count >= toomany) {
struct timeval now;
gettimeofday(&now, NULL);
if (now.tv_sec - sep->se_time.tv_sec >
CNT_INTVL) {
sep->se_time = now;
sep->se_count = 1;
} else {
syslog(LOG_ERR,
"%s/%s server failing (looping), service terminated",
sep->se_service, sep->se_proto);
if (sep->se_accept &&
sep->se_socktype == SOCK_STREAM)
close(ctrl);
close_sep(sep);
free_conn(conn);
sigsetmask(0L);
if (!timingout) {
timingout = 1;
alarm(RETRYTIME);
}
continue;
}
}
pid = fork();
}
if (pid < 0) {
syslog(LOG_ERR, "fork: %m");
if (sep->se_accept &&
sep->se_socktype == SOCK_STREAM)
close(ctrl);
free_conn(conn);
sigsetmask(0L);
sleep(1);
continue;
}
if (pid) {
addchild_conn(conn, pid);
addchild(sep, pid);
}
sigsetmask(0L);
if (pid == 0) {
if (dofork) {
sigaction(SIGALRM, &saalrm, NULL);
sigaction(SIGCHLD, &sachld, NULL);
sigaction(SIGHUP, &sahup, NULL);
/* SIGPIPE reset before exec */
}
/*
* Call tcpmux to find the real service to exec.
*/
if (sep->se_bi &&
sep->se_bi->bi_fn == (bi_fn_t *) tcpmux) {
sep = tcpmux(ctrl);
if (sep == NULL) {
close(ctrl);
_exit(0);
}
}
if (ISWRAP(sep)) {
inetd_setproctitle("wrapping", ctrl);
service = sep->se_server_name ?
sep->se_server_name : sep->se_service;
request_init(&req, RQ_DAEMON, service, RQ_FILE, ctrl, NULL);
fromhost(&req);
deny_severity = LIBWRAP_DENY_FACILITY|LIBWRAP_DENY_SEVERITY;
allow_severity = LIBWRAP_ALLOW_FACILITY|LIBWRAP_ALLOW_SEVERITY;
denied = !hosts_access(&req);
if (denied) {
syslog(deny_severity,
"refused connection from %.500s, service %s (%s%s)",
eval_client(&req), service, sep->se_proto,
(whichaf(&req) == AF_INET6) ? "6" : "");
if (sep->se_socktype != SOCK_STREAM)
recv(ctrl, buf, sizeof (buf), 0);
if (dofork) {
sleep(1);
_exit(0);
}
}
if (dolog) {
syslog(allow_severity,
"connection from %.500s, service %s (%s%s)",
eval_client(&req), service, sep->se_proto,
(whichaf(&req) == AF_INET6) ? "6" : "");
}
}
if (sep->se_bi) {
(*sep->se_bi->bi_fn)(ctrl, sep);
} else {
if (debug)
warnx("%d execl %s",
getpid(), sep->se_server);
/* Clear close-on-exec. */
if (fcntl(ctrl, F_SETFD, 0) < 0) {
syslog(LOG_ERR,
"%s/%s: fcntl (F_SETFD, 0): %m",
sep->se_service, sep->se_proto);
_exit(EX_OSERR);
}
if (ctrl != 0) {
dup2(ctrl, 0);
close(ctrl);
}
dup2(0, 1);
dup2(0, 2);
if ((pwd = getpwnam(sep->se_user)) == NULL) {
syslog(LOG_ERR,
"%s/%s: %s: no such user",
sep->se_service, sep->se_proto,
sep->se_user);
if (sep->se_socktype != SOCK_STREAM)
recv(0, buf, sizeof (buf), 0);
_exit(EX_NOUSER);
}
grp = NULL;
if ( sep->se_group != NULL
&& (grp = getgrnam(sep->se_group)) == NULL
) {
syslog(LOG_ERR,
"%s/%s: %s: no such group",
sep->se_service, sep->se_proto,
sep->se_group);
if (sep->se_socktype != SOCK_STREAM)
recv(0, buf, sizeof (buf), 0);
_exit(EX_NOUSER);
}
if (grp != NULL)
pwd->pw_gid = grp->gr_gid;
#ifdef LOGIN_CAP
if ((lc = login_getclass(sep->se_class)) == NULL) {
/* error syslogged by getclass */
syslog(LOG_ERR,
"%s/%s: %s: login class error",
sep->se_service, sep->se_proto,
sep->se_class);
if (sep->se_socktype != SOCK_STREAM)
recv(0, buf, sizeof (buf), 0);
_exit(EX_NOUSER);
}
#endif
if (setsid() < 0) {
syslog(LOG_ERR,
"%s: can't setsid(): %m",
sep->se_service);
/* _exit(EX_OSERR); not fatal yet */
}
#ifdef LOGIN_CAP
if (setusercontext(lc, pwd, pwd->pw_uid,
LOGIN_SETALL) != 0) {
syslog(LOG_ERR,
"%s: can't setusercontext(..%s..): %m",
sep->se_service, sep->se_user);
_exit(EX_OSERR);
}
login_close(lc);
#else
if (pwd->pw_uid) {
if (setlogin(sep->se_user) < 0) {
syslog(LOG_ERR,
"%s: can't setlogin(%s): %m",
sep->se_service, sep->se_user);
/* _exit(EX_OSERR); not yet */
}
if (setgid(pwd->pw_gid) < 0) {
syslog(LOG_ERR,
"%s: can't set gid %d: %m",
sep->se_service, pwd->pw_gid);
_exit(EX_OSERR);
}
initgroups(pwd->pw_name,
pwd->pw_gid);
if (setuid(pwd->pw_uid) < 0) {
syslog(LOG_ERR,
"%s: can't set uid %d: %m",
sep->se_service, pwd->pw_uid);
_exit(EX_OSERR);
}
}
#endif
sigaction(SIGPIPE, &sapipe, NULL);
execv(sep->se_server, sep->se_argv);
syslog(LOG_ERR,
"cannot execute %s: %m", sep->se_server);
if (sep->se_socktype != SOCK_STREAM)
recv(0, buf, sizeof (buf), 0);
}
if (dofork)
_exit(0);
}
if (sep->se_accept && sep->se_socktype == SOCK_STREAM)
close(ctrl);
}
}
}
/*
* Add a signal flag to the signal flag queue for later handling
*/
void
flag_signal(int c)
{
char ch = c;
if (write(signalpipe[1], &ch, 1) != 1) {
syslog(LOG_ERR, "write: %m");
_exit(EX_OSERR);
}
}
/*
* Record a new child pid for this service. If we've reached the
* limit on children, then stop accepting incoming requests.
*/
void
addchild(struct servtab *sep, pid_t pid)
{
if (sep->se_maxchild <= 0)
return;
#ifdef SANITY_CHECK
if (sep->se_numchild >= sep->se_maxchild) {
syslog(LOG_ERR, "%s: %d >= %d",
__func__, sep->se_numchild, sep->se_maxchild);
exit(EX_SOFTWARE);
}
#endif
sep->se_pids[sep->se_numchild++] = pid;
if (sep->se_numchild == sep->se_maxchild)
disable(sep);
}
/*
* Some child process has exited. See if it's on somebody's list.
*/
void
flag_reapchild(int signo __unused)
{
flag_signal('C');
}
void
reapchild(void)
{
int k, status;
pid_t pid;
struct servtab *sep;
for (;;) {
pid = wait3(&status, WNOHANG, NULL);
if (pid <= 0)
break;
if (debug)
warnx("%d reaped, %s %u", pid,
WIFEXITED(status) ? "status" : "signal",
WIFEXITED(status) ? WEXITSTATUS(status)
: WTERMSIG(status));
for (sep = servtab; sep; sep = sep->se_next) {
for (k = 0; k < sep->se_numchild; k++)
if (sep->se_pids[k] == pid)
break;
if (k == sep->se_numchild)
continue;
if (sep->se_numchild == sep->se_maxchild)
enable(sep);
sep->se_pids[k] = sep->se_pids[--sep->se_numchild];
if (WIFSIGNALED(status) || WEXITSTATUS(status))
syslog(LOG_WARNING,
"%s[%d]: exited, %s %u",
sep->se_server, pid,
WIFEXITED(status) ? "status" : "signal",
WIFEXITED(status) ? WEXITSTATUS(status)
: WTERMSIG(status));
break;
}
reapchild_conn(pid);
}
}
void
flag_config(int signo __unused)
{
flag_signal('H');
}
void
config(void)
{
struct servtab *sep, *new, **sepp;
long omask;
#ifdef LOGIN_CAP
login_cap_t *lc = NULL;
#endif
if (!setconfig()) {
syslog(LOG_ERR, "%s: %m", CONFIG);
return;
}
for (sep = servtab; sep; sep = sep->se_next)
sep->se_checked = 0;
while ((new = getconfigent())) {
if (getpwnam(new->se_user) == NULL) {
syslog(LOG_ERR,
"%s/%s: no such user '%s', service ignored",
new->se_service, new->se_proto, new->se_user);
continue;
}
if (new->se_group && getgrnam(new->se_group) == NULL) {
syslog(LOG_ERR,
"%s/%s: no such group '%s', service ignored",
new->se_service, new->se_proto, new->se_group);
continue;
}
#ifdef LOGIN_CAP
if ((lc = login_getclass(new->se_class)) == NULL) {
/* error syslogged by getclass */
syslog(LOG_ERR,
"%s/%s: %s: login class error, service ignored",
new->se_service, new->se_proto, new->se_class);
continue;
}
login_close(lc);
#endif
for (sep = servtab; sep; sep = sep->se_next)
if (strcmp(sep->se_service, new->se_service) == 0 &&
strcmp(sep->se_proto, new->se_proto) == 0 &&
sep->se_socktype == new->se_socktype &&
sep->se_family == new->se_family)
break;
if (sep != 0) {
int i;
#define SWAP(a, b) { typeof(a) c = a; a = b; b = c; }
omask = sigblock(SIGBLOCK);
if (sep->se_nomapped != new->se_nomapped) {
sep->se_nomapped = new->se_nomapped;
sep->se_reset = 1;
}
/* copy over outstanding child pids */
if (sep->se_maxchild > 0 && new->se_maxchild > 0) {
new->se_numchild = sep->se_numchild;