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NetBSD/usr.sbin/inetd/inetd.c
dholland e62b84ba61 When running a builtin service (a what? yeah, a piece of useless 
legacy code), if the builtin service forks (not all do), avoid leaking
listening sockets into the child process.

If the child process were to keep copies of the listening sockets
around and then hang about for a long time, it would prevent inetd
from being able to re-bind them upon restart.

The listening sockets are tagged close-on-exec, but that doesn't help
when one doesn't exec.

Patch from my own very old PR 8253.
2008-05-26 03:41:25 +00:00

2544 lines
59 KiB
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/* $NetBSD: inetd.c,v 1.105 2008/05/26 03:41:25 dholland Exp $ */
/*-
* Copyright (c) 1998, 2003 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Jason R. Thorpe of the Numerical Aerospace Simulation Facility,
* NASA Ames Research Center and by Matthias Scheler.
*
* 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.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
/*
* Copyright (c) 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. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/cdefs.h>
#ifndef lint
__COPYRIGHT("@(#) Copyright (c) 1983, 1991, 1993, 1994\n\
The Regents of the University of California. All rights reserved.\n");
#if 0
static char sccsid[] = "@(#)inetd.c 8.4 (Berkeley) 4/13/94";
#else
__RCSID("$NetBSD: inetd.c,v 1.105 2008/05/26 03:41:25 dholland Exp $");
#endif
#endif /* not lint */
/*
* 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 being with
* a space or tab. All fields must be present in each entry.
*
* service name must be in /etc/services or must
* name a tcpmux service
* socket type stream/dgram/raw/rdm/seqpacket
* protocol must be in /etc/protocols
* wait/nowait[:max] single-threaded/multi-threaded, max #
* user[:group] user/group to run daemon as
* server program full path name
* server program arguments maximum of MAXARGS (20)
*
* For RPC services
* service name/version must be in /etc/rpc
* socket type stream/dgram/raw/rdm/seqpacket
* protocol must be in /etc/protocols
* wait/nowait[:max] single-threaded/multi-threaded
* user[:group] user to run daemon as
* server program full path name
* server program arguments maximum of MAXARGS (20)
*
* For non-RPC services, the "service name" can be of the form
* hostaddress:servicename, in which case the hostaddress is used
* as the host portion of the address to listen on. If hostaddress
* consists of a single `*' character, INADDR_ANY is used.
*
* A line can also consist of just
* hostaddress:
* where hostaddress is as in the preceding paragraph. Such a line must
* have no further fields; the specified hostaddress is remembered and
* used for all further lines that have no hostaddress specified,
* until the next such line (or EOF). (This is why * is provided to
* allow explicit specification of INADDR_ANY.) A line
* *:
* is implicitly in effect at the beginning of the file.
*
* The hostaddress specifier may (and often will) contain dots;
* the service name must not.
*
* For RPC services, host-address specifiers are accepted and will
* work to some extent; however, because of limitations in the
* portmapper interface, it will not work to try to give more than
* one line for any given RPC service, even if the host-address
* specifiers are different.
*
* 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.
*
* 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
*/
/*
* Here's the scoop concerning the user:group feature:
*
* 1) set-group-option off.
*
* a) user = root: NO setuid() or setgid() is done
*
* b) other: setuid()
* setgid(primary group as found in passwd)
* initgroups(name, primary group)
*
* 2) set-group-option on.
*
* a) user = root: NO setuid()
* setgid(specified group)
* NO initgroups()
*
* b) other: setuid()
* setgid(specified group)
* initgroups(name, specified group)
*
*/
#include <sys/param.h>
#include <sys/stat.h>
#include <sys/ioctl.h>
#include <sys/socket.h>
#include <sys/un.h>
#include <sys/wait.h>
#include <sys/time.h>
#include <sys/resource.h>
#include <sys/event.h>
#ifndef RLIMIT_NOFILE
#define RLIMIT_NOFILE RLIMIT_OFILE
#endif
#ifndef NO_RPC
#define RPC
#endif
#include <net/if.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#ifdef RPC
#include <rpc/rpc.h>
#include <rpc/rpcb_clnt.h>
#include <netconfig.h>
#endif
#include <ctype.h>
#include <errno.h>
#include <fcntl.h>
#include <grp.h>
#include <netdb.h>
#include <pwd.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <syslog.h>
#include <unistd.h>
#include <util.h>
#include <ifaddrs.h>
#include "pathnames.h"
#ifdef IPSEC
#include <netinet6/ipsec.h>
#ifndef IPSEC_POLICY_IPSEC /* no ipsec support on old ipsec */
#undef IPSEC
#endif
#include "ipsec.h"
#endif
#ifdef LIBWRAP
# include <tcpd.h>
#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
int allow_severity = LIBWRAP_ALLOW_FACILITY|LIBWRAP_ALLOW_SEVERITY;
int deny_severity = LIBWRAP_DENY_FACILITY|LIBWRAP_DENY_SEVERITY;
#endif
#define TOOMANY 40 /* don't start more than TOOMANY */
#define CNT_INTVL 60 /* servers in CNT_INTVL sec. */
#define RETRYTIME (60*10) /* retry after bind or server fail */
#define A_CNT(a) (sizeof (a) / sizeof (a[0]))
int debug;
#ifdef LIBWRAP
int lflag;
#endif
int maxsock;
int kq;
int options;
int timingout;
struct servent *sp;
char *curdom;
const int niflags = NI_NUMERICHOST | NI_NUMERICSERV;
#ifndef OPEN_MAX
#define OPEN_MAX 64
#endif
/* Reserve some descriptors, 3 stdio + at least: 1 log, 1 conf. file */
#define FD_MARGIN (8)
rlim_t rlim_ofile_cur = OPEN_MAX;
#ifdef RLIMIT_NOFILE
struct rlimit rlim_ofile;
#endif
struct kevent changebuf[64];
size_t changes;
struct servtab {
char *se_hostaddr; /* host address to listen on */
char *se_service; /* name of service */
int se_socktype; /* type of socket to use */
int se_family; /* address family */
char *se_proto; /* protocol used */
int se_sndbuf; /* sndbuf size */
int se_rcvbuf; /* rcvbuf size */
int se_rpcprog; /* rpc program number */
int se_rpcversl; /* rpc program lowest version */
int se_rpcversh; /* rpc program highest version */
#define isrpcservice(sep) ((sep)->se_rpcversl != 0)
pid_t se_wait; /* single threaded server */
short se_checked; /* looked at during merge */
char *se_user; /* user name to run as */
char *se_group; /* group name to run as */
struct biltin *se_bi; /* if built-in, description */
char *se_server; /* server program */
#define MAXARGV 20
char *se_argv[MAXARGV+1]; /* program arguments */
#ifdef IPSEC
char *se_policy; /* IPsec poilcy string */
#endif
int se_fd; /* open descriptor */
int se_type; /* type */
union {
struct sockaddr se_un_ctrladdr;
struct sockaddr_in se_un_ctrladdr_in;
struct sockaddr_in6 se_un_ctrladdr_in6;
struct sockaddr_un se_un_ctrladdr_un;
} se_un; /* bound address */
#define se_ctrladdr se_un.se_un_ctrladdr
#define se_ctrladdr_in se_un.se_un_ctrladdr_in
#define se_ctrladdr_un se_un.se_un_ctrladdr_un
int se_ctrladdr_size;
int se_max; /* max # of instances of this service */
int se_count; /* number started since se_time */
struct timeval se_time; /* start of se_count */
#ifdef MULOG
int se_log;
#define MULOG_RFC931 0x40000000
#endif
struct servtab *se_next;
} *servtab;
#define NORM_TYPE 0
#define MUX_TYPE 1
#define MUXPLUS_TYPE 2
#define FAITH_TYPE 3
#define ISMUX(sep) (((sep)->se_type == MUX_TYPE) || \
((sep)->se_type == MUXPLUS_TYPE))
#define ISMUXPLUS(sep) ((sep)->se_type == MUXPLUS_TYPE)
static void chargen_dg(int, struct servtab *);
static void chargen_stream(int, struct servtab *);
static void close_sep(struct servtab *);
static void config(void);
static void daytime_dg(int, struct servtab *);
static void daytime_stream(int, struct servtab *);
static void discard_dg(int, struct servtab *);
static void discard_stream(int, struct servtab *);
static void echo_dg(int, struct servtab *);
static void echo_stream(int, struct servtab *);
static void endconfig(void);
static struct servtab *enter(struct servtab *);
static void freeconfig(struct servtab *);
static struct servtab *getconfigent(void);
static void goaway(void);
static void machtime_dg(int, struct servtab *);
static void machtime_stream(int, struct servtab *);
static char *newstr(char *);
static char *nextline(FILE *);
static void print_service(char *, struct servtab *);
static void reapchild(void);
static void retry(void);
static void run_service(int, struct servtab *, int);
static int setconfig(void);
static void setup(struct servtab *);
static char *sskip(char **);
static char *skip(char **);
static void tcpmux(int, struct servtab *);
static void usage(void);
static void register_rpc(struct servtab *);
static void unregister_rpc(struct servtab *);
static void bump_nofile(void);
static void inetd_setproctitle(char *, int);
static void initring(void);
static uint32_t machtime(void);
static int port_good_dg(struct sockaddr *);
static int dg_broadcast(struct in_addr *);
static int my_kevent(const struct kevent *, size_t, struct kevent *,
size_t);
static struct kevent * allocchange(void);
static int getline(int, char *, int);
static void spawn(struct servtab *, int);
#ifdef MULOG
static void dolog(struct servtab *, int);
static void timeout(int);
static char *rfc931_name(struct sockaddr *, int);
#endif
struct biltin {
char *bi_service; /* internally provided service name */
int bi_socktype; /* type of socket supported */
short bi_fork; /* 1 if should fork before call */
short bi_wait; /* 1 if should wait for child */
void (*bi_fn)(int, struct servtab *);
/* function which performs it */
} biltins[] = {
/* Echo received data */
{ "echo", SOCK_STREAM, 1, 0, echo_stream },
{ "echo", SOCK_DGRAM, 0, 0, echo_dg },
/* Internet /dev/null */
{ "discard", SOCK_STREAM, 1, 0, discard_stream },
{ "discard", SOCK_DGRAM, 0, 0, discard_dg },
/* Return 32 bit time since 1970 */
{ "time", SOCK_STREAM, 0, 0, machtime_stream },
{ "time", SOCK_DGRAM, 0, 0, machtime_dg },
/* Return human-readable time */
{ "daytime", SOCK_STREAM, 0, 0, daytime_stream },
{ "daytime", SOCK_DGRAM, 0, 0, daytime_dg },
/* Familiar character generator */
{ "chargen", SOCK_STREAM, 1, 0, chargen_stream },
{ "chargen", SOCK_DGRAM, 0, 0, chargen_dg },
{ "tcpmux", SOCK_STREAM, 1, 0, tcpmux },
{ NULL }
};
/* list of "bad" ports. I.e. ports that are most obviously used for
* "cycling packets" denial of service attacks. See /etc/services.
* List must end with port number "0".
*/
u_int16_t bad_ports[] = { 7, 9, 13, 19, 37, 0 };
#define NUMINT (sizeof(intab) / sizeof(struct inent))
char *CONFIG = _PATH_INETDCONF;
static int my_signals[] =
{ SIGALRM, SIGHUP, SIGCHLD, SIGTERM, SIGINT, SIGPIPE };
int
main(int argc, char *argv[])
{
int ch, n, reload = 1;
while ((ch = getopt(argc, argv,
#ifdef LIBWRAP
"dl"
#else
"d"
#endif
)) != -1)
switch(ch) {
case 'd':
debug = 1;
options |= SO_DEBUG;
break;
#ifdef LIBWRAP
case 'l':
lflag = 1;
break;
#endif
case '?':
default:
usage();
}
argc -= optind;
argv += optind;
if (argc > 0)
CONFIG = argv[0];
if (!debug)
daemon(0, 0);
openlog("inetd", LOG_PID | LOG_NOWAIT, LOG_DAEMON);
pidfile(NULL);
kq = kqueue();
if (kq < 0) {
syslog(LOG_ERR, "kqueue: %m");
return (EXIT_FAILURE);
}
#ifdef RLIMIT_NOFILE
if (getrlimit(RLIMIT_NOFILE, &rlim_ofile) < 0) {
syslog(LOG_ERR, "getrlimit: %m");
} else {
rlim_ofile_cur = rlim_ofile.rlim_cur;
if (rlim_ofile_cur == RLIM_INFINITY) /* ! */
rlim_ofile_cur = OPEN_MAX;
}
#endif
for (n = 0; n < (int)A_CNT(my_signals); n++) {
int signum;
signum = my_signals[n];
if (signum != SIGCHLD)
(void) signal(signum, SIG_IGN);
if (signum != SIGPIPE) {
struct kevent *ev;
ev = allocchange();
EV_SET(ev, signum, EVFILT_SIGNAL, EV_ADD | EV_ENABLE,
0, 0, 0);
}
}
for (;;) {
int ctrl;
struct kevent eventbuf[64], *ev;
struct servtab *sep;
if (reload) {
reload = 0;
config();
}
n = my_kevent(changebuf, changes, eventbuf, A_CNT(eventbuf));
changes = 0;
for (ev = eventbuf; n > 0; ev++, n--) {
if (ev->filter == EVFILT_SIGNAL) {
switch (ev->ident) {
case SIGALRM:
retry();
break;
case SIGCHLD:
reapchild();
break;
case SIGTERM:
case SIGINT:
goaway();
break;
case SIGHUP:
reload = 1;
break;
}
continue;
}
if (ev->filter != EVFILT_READ)
continue;
sep = (struct servtab *)ev->udata;
/* Paranoia */
if ((int)ev->ident != sep->se_fd)
continue;
if (debug)
fprintf(stderr, "someone wants %s\n",
sep->se_service);
if (!sep->se_wait && sep->se_socktype == SOCK_STREAM) {
/* XXX here do the libwrap check-before-accept*/
ctrl = accept(sep->se_fd, NULL, NULL);
if (debug)
fprintf(stderr, "accept, ctrl %d\n",
ctrl);
if (ctrl < 0) {
if (errno != EINTR)
syslog(LOG_WARNING,
"accept (for %s): %m",
sep->se_service);
continue;
}
} else
ctrl = sep->se_fd;
spawn(sep, ctrl);
}
}
}
static void
spawn(struct servtab *sep, int ctrl)
{
int dofork;
pid_t pid;
pid = 0;
#ifdef LIBWRAP_INTERNAL
dofork = 1;
#else
dofork = (sep->se_bi == 0 || sep->se_bi->bi_fork);
#endif
if (dofork) {
if (sep->se_count++ == 0)
(void)gettimeofday(&sep->se_time, NULL);
else if (sep->se_count >= sep->se_max) {
struct timeval now;
(void)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 max spawn rate (%d in %d seconds) "
"exceeded; service not started",
sep->se_service, sep->se_proto,
sep->se_max, CNT_INTVL);
if (!sep->se_wait && sep->se_socktype ==
SOCK_STREAM)
close(ctrl);
close_sep(sep);
if (!timingout) {
timingout = 1;
alarm(RETRYTIME);
}
return;
}
}
pid = fork();
if (pid < 0) {
syslog(LOG_ERR, "fork: %m");
if (!sep->se_wait && sep->se_socktype == SOCK_STREAM)
close(ctrl);
sleep(1);
return;
}
if (pid != 0 && sep->se_wait) {
struct kevent *ev;
sep->se_wait = pid;
ev = allocchange();
EV_SET(ev, sep->se_fd, EVFILT_READ,
EV_DELETE, 0, 0, 0);
}
if (pid == 0) {
size_t n;
for (n = 0; n < A_CNT(my_signals); n++)
(void) signal(my_signals[n], SIG_DFL);
if (debug)
setsid();
}
}
if (pid == 0) {
run_service(ctrl, sep, dofork);
if (dofork)
exit(0);
}
if (!sep->se_wait && sep->se_socktype == SOCK_STREAM)
close(ctrl);
}
static void
run_service(int ctrl, struct servtab *sep, int didfork)
{
struct passwd *pwd;
struct group *grp = NULL; /* XXX gcc */
char buf[NI_MAXSERV];
struct servtab *s;
#ifdef LIBWRAP
struct request_info req;
int denied;
char *service = NULL; /* XXX gcc */
#endif
#ifdef LIBWRAP
#ifndef LIBWRAP_INTERNAL
if (sep->se_bi == 0)
#endif
if (!sep->se_wait && sep->se_socktype == SOCK_STREAM) {
request_init(&req, RQ_DAEMON, sep->se_argv[0] ?
sep->se_argv[0] : sep->se_service, RQ_FILE, ctrl, NULL);
fromhost(&req);
denied = !hosts_access(&req);
if (denied || lflag) {
if (getnameinfo(&sep->se_ctrladdr,
sep->se_ctrladdr.sa_len, NULL, 0,
buf, sizeof(buf), 0) != 0) {
/* shouldn't happen */
(void)snprintf(buf, sizeof buf, "%d",
ntohs(sep->se_ctrladdr_in.sin_port));
}
service = buf;
}
if (denied) {
syslog(deny_severity,
"refused connection from %.500s, service %s (%s)",
eval_client(&req), service, sep->se_proto);
goto reject;
}
if (lflag) {
syslog(allow_severity,
"connection from %.500s, service %s (%s)",
eval_client(&req), service, sep->se_proto);
}
}
#endif /* LIBWRAP */
if (sep->se_bi) {
if (didfork) {
for (s = servtab; s; s = s->se_next)
if (s->se_fd != -1 && s->se_fd != ctrl)
close(s->se_fd);
}
(*sep->se_bi->bi_fn)(ctrl, sep);
} else {
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);
goto reject;
}
if (sep->se_group &&
(grp = getgrnam(sep->se_group)) == NULL) {
syslog(LOG_ERR, "%s/%s: %s: No such group",
sep->se_service, sep->se_proto, sep->se_group);
goto reject;
}
if (pwd->pw_uid) {
if (sep->se_group)
pwd->pw_gid = grp->gr_gid;
if (setgid(pwd->pw_gid) < 0) {
syslog(LOG_ERR,
"%s/%s: can't set gid %d: %m", sep->se_service,
sep->se_proto, pwd->pw_gid);
goto reject;
}
(void) initgroups(pwd->pw_name,
pwd->pw_gid);
if (setuid(pwd->pw_uid) < 0) {
syslog(LOG_ERR,
"%s/%s: can't set uid %d: %m", sep->se_service,
sep->se_proto, pwd->pw_uid);
goto reject;
}
} else if (sep->se_group) {
(void) setgid((gid_t)grp->gr_gid);
}
if (debug)
fprintf(stderr, "%d execl %s\n",
getpid(), sep->se_server);
#ifdef MULOG
if (sep->se_log)
dolog(sep, ctrl);
#endif
/* Set our control descriptor to not close-on-exec... */
if (fcntl(ctrl, F_SETFD, 0) < 0)
syslog(LOG_ERR, "fcntl (F_SETFD, 0): %m");
/* ...and dup it to stdin, stdout, and stderr. */
if (ctrl != 0) {
dup2(ctrl, 0);
close(ctrl);
ctrl = 0;
}
dup2(0, 1);
dup2(0, 2);
#ifdef RLIMIT_NOFILE
if (rlim_ofile.rlim_cur != rlim_ofile_cur &&
setrlimit(RLIMIT_NOFILE, &rlim_ofile) < 0)
syslog(LOG_ERR, "setrlimit: %m");
#endif
execv(sep->se_server, sep->se_argv);
syslog(LOG_ERR, "cannot execute %s: %m", sep->se_server);
reject:
if (sep->se_socktype != SOCK_STREAM)
recv(ctrl, buf, sizeof (buf), 0);
_exit(1);
}
}
static void
reapchild(void)
{
int status;
pid_t pid;
struct servtab *sep;
for (;;) {
pid = wait3(&status, WNOHANG, NULL);
if (pid <= 0)
break;
if (debug)
(void) fprintf(stderr, "%d reaped, status %#x\n",
pid, status);
for (sep = servtab; sep != NULL; sep = sep->se_next)
if (sep->se_wait == pid) {
struct kevent *ev;
if (WIFEXITED(status) && WEXITSTATUS(status))
syslog(LOG_WARNING,
"%s: exit status 0x%x",
sep->se_server, WEXITSTATUS(status));
else if (WIFSIGNALED(status))
syslog(LOG_WARNING,
"%s: exit signal 0x%x",
sep->se_server, WTERMSIG(status));
sep->se_wait = 1;
ev = allocchange();
EV_SET(ev, sep->se_fd, EVFILT_READ,
EV_ADD | EV_ENABLE, 0, 0, (intptr_t)sep);
if (debug)
fprintf(stderr, "restored %s, fd %d\n",
sep->se_service, sep->se_fd);
}
}
}
static void
config(void)
{
struct servtab *sep, *cp, **sepp;
size_t n;
if (!setconfig()) {
syslog(LOG_ERR, "%s: %m", CONFIG);
return;
}
for (sep = servtab; sep != NULL; sep = sep->se_next)
sep->se_checked = 0;
while ((cp = getconfigent())) {
for (sep = servtab; sep != NULL; sep = sep->se_next)
if (strcmp(sep->se_service, cp->se_service) == 0 &&
strcmp(sep->se_hostaddr, cp->se_hostaddr) == 0 &&
strcmp(sep->se_proto, cp->se_proto) == 0 &&
ISMUX(sep) == ISMUX(cp))
break;
if (sep != NULL) {
int i;
#define SWAP(type, a, b) {type c = a; a = b; b = c;}
/*
* sep->se_wait may be holding the pid of a daemon
* that we're waiting for. If so, don't overwrite
* it unless the config file explicitly says don't
* wait.
*/
if (cp->se_bi == 0 &&
(sep->se_wait == 1 || cp->se_wait == 0))
sep->se_wait = cp->se_wait;
SWAP(char *, sep->se_user, cp->se_user);
SWAP(char *, sep->se_group, cp->se_group);
SWAP(char *, sep->se_server, cp->se_server);
for (i = 0; i < MAXARGV; i++)
SWAP(char *, sep->se_argv[i], cp->se_argv[i]);
#ifdef IPSEC
SWAP(char *, sep->se_policy, cp->se_policy);
#endif
SWAP(int, cp->se_type, sep->se_type);
SWAP(int, cp->se_max, sep->se_max);
#undef SWAP
if (isrpcservice(sep))
unregister_rpc(sep);
sep->se_rpcversl = cp->se_rpcversl;
sep->se_rpcversh = cp->se_rpcversh;
freeconfig(cp);
if (debug)
print_service("REDO", sep);
} else {
sep = enter(cp);
if (debug)
print_service("ADD ", sep);
}
sep->se_checked = 1;
switch (sep->se_family) {
case AF_LOCAL:
if (sep->se_fd != -1)
break;
n = strlen(sep->se_service);
if (n > sizeof(sep->se_ctrladdr_un.sun_path)) {
syslog(LOG_ERR, "%s: address too long",
sep->se_service);
sep->se_checked = 0;
continue;
}
(void)unlink(sep->se_service);
strncpy(sep->se_ctrladdr_un.sun_path,
sep->se_service, n);
sep->se_ctrladdr_un.sun_family = AF_LOCAL;
sep->se_ctrladdr_size = n +
sizeof(sep->se_ctrladdr_un) -
sizeof(sep->se_ctrladdr_un.sun_path);
if (!ISMUX(sep))
setup(sep);
break;
case AF_INET:
#ifdef INET6
case AF_INET6:
#endif
{
struct addrinfo hints, *res;
char *host, *port;
int error;
int s;
/* check if the family is supported */
s = socket(sep->se_family, SOCK_DGRAM, 0);
if (s < 0) {
syslog(LOG_WARNING,
"%s/%s: %s: the address family is not "
"supported by the kernel",
sep->se_service, sep->se_proto,
sep->se_hostaddr);
sep->se_checked = 0;
continue;
}
close(s);
memset(&hints, 0, sizeof(hints));
hints.ai_family = sep->se_family;
hints.ai_socktype = sep->se_socktype;
hints.ai_flags = AI_PASSIVE;
if (!strcmp(sep->se_hostaddr, "*"))
host = NULL;
else
host = sep->se_hostaddr;
if (isrpcservice(sep) || ISMUX(sep))
port = "0";
else
port = sep->se_service;
error = getaddrinfo(host, port, &hints, &res);
if (error) {
if (error == EAI_SERVICE) {
/* gai_strerror not friendly enough */
syslog(LOG_WARNING, "%s/%s: "
"unknown service",
sep->se_service, sep->se_proto);
} else {
syslog(LOG_ERR, "%s/%s: %s: %s",
sep->se_service, sep->se_proto,
sep->se_hostaddr,
gai_strerror(error));
}
sep->se_checked = 0;
continue;
}
if (res->ai_next) {
syslog(LOG_ERR,
"%s/%s: %s: resolved to multiple addr",
sep->se_service, sep->se_proto,
sep->se_hostaddr);
sep->se_checked = 0;
freeaddrinfo(res);
continue;
}
memcpy(&sep->se_ctrladdr, res->ai_addr,
res->ai_addrlen);
if (ISMUX(sep)) {
sep->se_fd = -1;
freeaddrinfo(res);
continue;
}
sep->se_ctrladdr_size = res->ai_addrlen;
freeaddrinfo(res);
#ifdef RPC
if (isrpcservice(sep)) {
struct rpcent *rp;
sep->se_rpcprog = atoi(sep->se_service);
if (sep->se_rpcprog == 0) {
rp = getrpcbyname(sep->se_service);
if (rp == 0) {
syslog(LOG_ERR,
"%s/%s: unknown service",
sep->se_service,
sep->se_proto);
sep->se_checked = 0;
continue;
}
sep->se_rpcprog = rp->r_number;
}
if (sep->se_fd == -1 && !ISMUX(sep))
setup(sep);
if (sep->se_fd != -1)
register_rpc(sep);
} else
#endif
{
if (sep->se_fd >= 0)
close_sep(sep);
if (sep->se_fd == -1 && !ISMUX(sep))
setup(sep);
}
}
}
}
endconfig();
/*
* Purge anything not looked at above.
*/
sepp = &servtab;
while ((sep = *sepp)) {
if (sep->se_checked) {
sepp = &sep->se_next;
continue;
}
*sepp = sep->se_next;
if (sep->se_fd >= 0)
close_sep(sep);
if (isrpcservice(sep))
unregister_rpc(sep);
if (sep->se_family == AF_LOCAL)
(void)unlink(sep->se_service);
if (debug)
print_service("FREE", sep);
freeconfig(sep);
free(sep);
}
}
static void
retry(void)
{
struct servtab *sep;
timingout = 0;
for (sep = servtab; sep != NULL; sep = sep->se_next) {
if (sep->se_fd == -1 && !ISMUX(sep)) {
switch (sep->se_family) {
case AF_LOCAL:
case AF_INET:
#ifdef INET6
case AF_INET6:
#endif
setup(sep);
if (sep->se_fd != -1 && isrpcservice(sep))
register_rpc(sep);
break;
}
}
}
}
static void
goaway(void)
{
struct servtab *sep;
for (sep = servtab; sep != NULL; sep = sep->se_next) {
if (sep->se_fd == -1)
continue;
switch (sep->se_family) {
case AF_LOCAL:
(void)unlink(sep->se_service);
break;
case AF_INET:
#ifdef INET6
case AF_INET6:
#endif
if (sep->se_wait == 1 && isrpcservice(sep))
unregister_rpc(sep);
break;
}
(void)close(sep->se_fd);
}
exit(0);
}
static void
setup(struct servtab *sep)
{
int on = 1;
#ifdef INET6
int off = 0;
#endif
struct kevent *ev;
if ((sep->se_fd = socket(sep->se_family, sep->se_socktype, 0)) < 0) {
if (debug)
fprintf(stderr, "socket failed on %s/%s: %s\n",
sep->se_service, sep->se_proto, strerror(errno));
syslog(LOG_ERR, "%s/%s: socket: %m",
sep->se_service, sep->se_proto);
return;
}
/* Set all listening sockets to close-on-exec. */
if (fcntl(sep->se_fd, F_SETFD, FD_CLOEXEC) < 0) {
syslog(LOG_ERR, "%s/%s: fcntl(F_SETFD, FD_CLOEXEC): %m",
sep->se_service, sep->se_proto);
close(sep->se_fd);
return;
}
#define turnon(fd, opt) \
setsockopt(fd, SOL_SOCKET, opt, (char *)&on, sizeof (on))
if (strcmp(sep->se_proto, "tcp") == 0 && (options & SO_DEBUG) &&
turnon(sep->se_fd, SO_DEBUG) < 0)
syslog(LOG_ERR, "setsockopt (SO_DEBUG): %m");
if (turnon(sep->se_fd, SO_REUSEADDR) < 0)
syslog(LOG_ERR, "setsockopt (SO_REUSEADDR): %m");
#undef turnon
/* Set the socket buffer sizes, if specified. */
if (sep->se_sndbuf != 0 && setsockopt(sep->se_fd, SOL_SOCKET,
SO_SNDBUF, (char *)&sep->se_sndbuf, sizeof(sep->se_sndbuf)) < 0)
syslog(LOG_ERR, "setsockopt (SO_SNDBUF %d): %m",
sep->se_sndbuf);
if (sep->se_rcvbuf != 0 && setsockopt(sep->se_fd, SOL_SOCKET,
SO_RCVBUF, (char *)&sep->se_rcvbuf, sizeof(sep->se_rcvbuf)) < 0)
syslog(LOG_ERR, "setsockopt (SO_RCVBUF %d): %m",
sep->se_rcvbuf);
#ifdef INET6
if (sep->se_family == AF_INET6) {
int *v;
v = (sep->se_type == FAITH_TYPE) ? &on : &off;
if (setsockopt(sep->se_fd, IPPROTO_IPV6, IPV6_FAITH,
(char *)v, sizeof(*v)) < 0)
syslog(LOG_ERR, "setsockopt (IPV6_FAITH): %m");
}
#endif
#ifdef IPSEC
if (ipsecsetup(sep->se_family, sep->se_fd, sep->se_policy) < 0 &&
sep->se_policy) {
syslog(LOG_ERR, "%s/%s: ipsec setup failed",
sep->se_service, sep->se_proto);
(void)close(sep->se_fd);
sep->se_fd = -1;
return;
}
#endif
if (bind(sep->se_fd, &sep->se_ctrladdr, sep->se_ctrladdr_size) < 0) {
if (debug)
fprintf(stderr, "bind failed on %s/%s: %s\n",
sep->se_service, sep->se_proto, strerror(errno));
syslog(LOG_ERR, "%s/%s: bind: %m",
sep->se_service, sep->se_proto);
(void) close(sep->se_fd);
sep->se_fd = -1;
if (!timingout) {
timingout = 1;
alarm(RETRYTIME);
}
return;
}
if (sep->se_socktype == SOCK_STREAM)
listen(sep->se_fd, 10);
ev = allocchange();
EV_SET(ev, sep->se_fd, EVFILT_READ, EV_ADD | EV_ENABLE, 0, 0,
(intptr_t)sep);
if (sep->se_fd > maxsock) {
maxsock = sep->se_fd;
if (maxsock > rlim_ofile_cur - FD_MARGIN)
bump_nofile();
}
if (debug)
fprintf(stderr, "registered %s on %d\n",
sep->se_server, sep->se_fd);
}
/*
* Finish with a service and its socket.
*/
static void
close_sep(struct servtab *sep)
{
if (sep->se_fd >= 0) {
(void) close(sep->se_fd);
sep->se_fd = -1;
}
sep->se_count = 0;
}
static void
register_rpc(struct servtab *sep)
{
#ifdef RPC
struct netbuf nbuf;
struct sockaddr_storage ss;
struct netconfig *nconf;
socklen_t socklen;
int n;
if ((nconf = getnetconfigent(sep->se_proto+4)) == NULL) {
syslog(LOG_ERR, "%s: getnetconfigent failed",
sep->se_proto);
return;
}
socklen = sizeof ss;
if (getsockname(sep->se_fd, (struct sockaddr *)&ss, &socklen) < 0) {
syslog(LOG_ERR, "%s/%s: getsockname: %m",
sep->se_service, sep->se_proto);
return;
}
nbuf.buf = &ss;
nbuf.len = ss.ss_len;
nbuf.maxlen = sizeof (struct sockaddr_storage);
for (n = sep->se_rpcversl; n <= sep->se_rpcversh; n++) {
if (debug)
fprintf(stderr, "rpcb_set: %u %d %s %s\n",
sep->se_rpcprog, n, nconf->nc_netid,
taddr2uaddr(nconf, &nbuf));
(void)rpcb_unset(sep->se_rpcprog, n, nconf);
if (!rpcb_set(sep->se_rpcprog, n, nconf, &nbuf))
syslog(LOG_ERR, "rpcb_set: %u %d %s %s%s",
sep->se_rpcprog, n, nconf->nc_netid,
taddr2uaddr(nconf, &nbuf), clnt_spcreateerror(""));
}
#endif /* RPC */
}
static void
unregister_rpc(struct servtab *sep)
{
#ifdef RPC
int n;
struct netconfig *nconf;
if ((nconf = getnetconfigent(sep->se_proto+4)) == NULL) {
syslog(LOG_ERR, "%s: getnetconfigent failed",
sep->se_proto);
return;
}
for (n = sep->se_rpcversl; n <= sep->se_rpcversh; n++) {
if (debug)
fprintf(stderr, "rpcb_unset(%u, %d, %s)\n",
sep->se_rpcprog, n, nconf->nc_netid);
if (!rpcb_unset(sep->se_rpcprog, n, nconf))
syslog(LOG_ERR, "rpcb_unset(%u, %d, %s) failed\n",
sep->se_rpcprog, n, nconf->nc_netid);
}
#endif /* RPC */
}
static struct servtab *
enter(struct servtab *cp)
{
struct servtab *sep;
sep = (struct servtab *)malloc(sizeof (*sep));
if (sep == NULL) {
syslog(LOG_ERR, "Out of memory.");
exit(1);
}
*sep = *cp;
sep->se_fd = -1;
sep->se_rpcprog = -1;
sep->se_next = servtab;
servtab = sep;
return (sep);
}
FILE *fconfig = NULL;
struct servtab serv;
char line[LINE_MAX];
char *defhost;
#ifdef IPSEC
static char *policy = NULL;
#endif
static int
setconfig(void)
{
if (defhost)
free(defhost);
defhost = newstr("*");
#ifdef IPSEC
if (policy)
free(policy);
policy = NULL;
#endif
if (fconfig != NULL) {
fseek(fconfig, 0L, SEEK_SET);
return (1);
}
fconfig = fopen(CONFIG, "r");
return (fconfig != NULL);
}
static void
endconfig(void)
{
if (fconfig != NULL) {
(void) fclose(fconfig);
fconfig = NULL;
}
if (defhost != NULL) {
free(defhost);
defhost = NULL;
}
}
static struct servtab *
getconfigent(void)
{
struct servtab *sep = &serv;
int argc, val;
char *cp, *cp0, *arg, *buf0, *buf1, *sz0, *sz1;
static char TCPMUX_TOKEN[] = "tcpmux/";
#define MUX_LEN (sizeof(TCPMUX_TOKEN)-1)
char *hostdelim;
more:
while ((cp = nextline(fconfig))) {
#ifdef IPSEC
/* lines starting with #@ is not a comment, but the policy */
if (cp[0] == '#' && cp[1] == '@') {
char *p;
for (p = cp + 2; p && *p && isspace((unsigned char)*p); p++)
;
if (*p == '\0') {
if (policy)
free(policy);
policy = NULL;
} else {
if (ipsecsetup_test(p) < 0) {
syslog(LOG_ERR,
"%s: invalid ipsec policy \"%s\"",
CONFIG, p);
exit(1);
} else {
if (policy)
free(policy);
policy = newstr(p);
}
}
}
#endif
if (*cp == '#' || *cp == '\0')
continue;
#ifdef MULOG
/* Avoid use of `skip' if there is a danger of it looking
* at continuation lines.
*/
do {
cp++;
} while (*cp == ' ' || *cp == '\t');
if (*cp == '\0')
continue;
if ((arg = skip(&cp)) == NULL)
continue;
if (strcmp(arg, "DOMAIN"))
continue;
if (curdom)
free(curdom);
curdom = NULL;
while (*cp == ' ' || *cp == '\t')
cp++;
if (*cp == '\0')
continue;
arg = cp;
while (*cp && *cp != ' ' && *cp != '\t')
cp++;
if (*cp != '\0')
*cp++ = '\0';
curdom = newstr(arg);
#endif
break;
}
if (cp == NULL)
return (NULL);
/*
* clear the static buffer, since some fields (se_ctrladdr,
* for example) don't get initialized here.
*/
memset((caddr_t)sep, 0, sizeof *sep);
arg = skip(&cp);
if (cp == NULL) {
/* got an empty line containing just blanks/tabs. */
goto more;
}
/* Check for a host name. */
hostdelim = strrchr(arg, ':');
if (hostdelim) {
*hostdelim = '\0';
if (arg[0] == '[' && hostdelim > arg && hostdelim[-1] == ']') {
hostdelim[-1] = '\0';
sep->se_hostaddr = newstr(arg + 1);
} else
sep->se_hostaddr = newstr(arg);
arg = hostdelim + 1;
/*
* If the line is of the form `host:', then just change the
* default host for the following lines.
*/
if (*arg == '\0') {
arg = skip(&cp);
if (cp == NULL) {
free(defhost);
defhost = sep->se_hostaddr;
goto more;
}
}
} else
sep->se_hostaddr = newstr(defhost);
if (strncmp(arg, TCPMUX_TOKEN, MUX_LEN) == 0) {
char *c = arg + MUX_LEN;
if (*c == '+') {
sep->se_type = MUXPLUS_TYPE;
c++;
} else
sep->se_type = MUX_TYPE;
sep->se_service = newstr(c);
} else {
sep->se_service = newstr(arg);
sep->se_type = NORM_TYPE;
}
arg = sskip(&cp);
if (strcmp(arg, "stream") == 0)
sep->se_socktype = SOCK_STREAM;
else if (strcmp(arg, "dgram") == 0)
sep->se_socktype = SOCK_DGRAM;
else if (strcmp(arg, "rdm") == 0)
sep->se_socktype = SOCK_RDM;
else if (strcmp(arg, "seqpacket") == 0)
sep->se_socktype = SOCK_SEQPACKET;
else if (strcmp(arg, "raw") == 0)
sep->se_socktype = SOCK_RAW;
else
sep->se_socktype = -1;
arg = sskip(&cp);
if (sep->se_type == NORM_TYPE &&
strncmp(arg, "faith/", strlen("faith/")) == 0) {
arg += strlen("faith/");
sep->se_type = FAITH_TYPE;
}
sep->se_proto = newstr(arg);
#define MALFORMED(arg) \
do { \
syslog(LOG_ERR, "%s: malformed buffer size option `%s'", \
sep->se_service, (arg)); \
goto more; \
} while (0)
#define GETVAL(arg) \
do { \
if (!isdigit((unsigned char)*(arg))) \
MALFORMED(arg); \
val = strtol((arg), &cp0, 10); \
if (cp0 != NULL) { \
if (cp0[1] != '\0') \
MALFORMED((arg)); \
if (cp0[0] == 'k') \
val *= 1024; \
if (cp0[0] == 'm') \
val *= 1024 * 1024; \
} \
if (val < 1) { \
syslog(LOG_ERR, "%s: invalid buffer size `%s'", \
sep->se_service, (arg)); \
goto more; \
} \
} while (0)
#define ASSIGN(arg) \
do { \
if (strcmp((arg), "sndbuf") == 0) \
sep->se_sndbuf = val; \
else if (strcmp((arg), "rcvbuf") == 0) \
sep->se_rcvbuf = val; \
else \
MALFORMED((arg)); \
} while (0)
/*
* Extract the send and receive buffer sizes before parsing
* the protocol.
*/
sep->se_sndbuf = sep->se_rcvbuf = 0;
buf0 = buf1 = sz0 = sz1 = NULL;
if ((buf0 = strchr(sep->se_proto, ',')) != NULL) {
/* Not meaningful for Tcpmux services. */
if (ISMUX(sep)) {
syslog(LOG_ERR, "%s: can't specify buffer sizes for "
"tcpmux services", sep->se_service);
goto more;
}
/* Skip the , */
*buf0++ = '\0';
/* Check to see if another socket buffer size was specified. */
if ((buf1 = strchr(buf0, ',')) != NULL) {
/* Skip the , */
*buf1++ = '\0';
/* Make sure a 3rd one wasn't specified. */
if (strchr(buf1, ',') != NULL) {
syslog(LOG_ERR, "%s: too many buffer sizes",
sep->se_service);
goto more;
}
/* Locate the size. */
if ((sz1 = strchr(buf1, '=')) == NULL)
MALFORMED(buf1);
/* Skip the = */
*sz1++ = '\0';
}
/* Locate the size. */
if ((sz0 = strchr(buf0, '=')) == NULL)
MALFORMED(buf0);
/* Skip the = */
*sz0++ = '\0';
GETVAL(sz0);
ASSIGN(buf0);
if (buf1 != NULL) {
GETVAL(sz1);
ASSIGN(buf1);
}
}
#undef ASSIGN
#undef GETVAL
#undef MALFORMED
if (strcmp(sep->se_proto, "unix") == 0) {
sep->se_family = AF_LOCAL;
} else {
val = strlen(sep->se_proto);
if (!val) {
syslog(LOG_ERR, "%s: invalid protocol specified",
sep->se_service);
goto more;
}
val = sep->se_proto[val - 1];
switch (val) {
case '4': /*tcp4 or udp4*/
sep->se_family = AF_INET;
break;
#ifdef INET6
case '6': /*tcp6 or udp6*/
sep->se_family = AF_INET6;
break;
#endif
default:
sep->se_family = AF_INET; /*will become AF_INET6*/
break;
}
if (strncmp(sep->se_proto, "rpc/", 4) == 0) {
#ifdef RPC
char *cp, *ccp;
cp = strchr(sep->se_service, '/');
if (cp == 0) {
syslog(LOG_ERR, "%s: no rpc version",
sep->se_service);
goto more;
}
*cp++ = '\0';
sep->se_rpcversl = sep->se_rpcversh =
strtol(cp, &ccp, 0);
if (ccp == cp) {
badafterall:
syslog(LOG_ERR, "%s/%s: bad rpc version",
sep->se_service, cp);
goto more;
}
if (*ccp == '-') {
cp = ccp + 1;
sep->se_rpcversh = strtol(cp, &ccp, 0);
if (ccp == cp)
goto badafterall;
}
#else
syslog(LOG_ERR, "%s: rpc services not suported",
sep->se_service);
goto more;
#endif /* RPC */
}
}
arg = sskip(&cp);
{
char *cp;
if ((cp = strchr(arg, ':')) == NULL)
cp = strchr(arg, '.');
if (cp != NULL) {
*cp++ = '\0';
sep->se_max = atoi(cp);
} else
sep->se_max = TOOMANY;
}
sep->se_wait = strcmp(arg, "wait") == 0;
if (ISMUX(sep)) {
/*
* Silently enforce "nowait" for TCPMUX services since
* they don't have an assigned port to listen on.
*/
sep->se_wait = 0;
if (strncmp(sep->se_proto, "tcp", 3)) {
syslog(LOG_ERR,
"%s: bad protocol for tcpmux service %s",
CONFIG, sep->se_service);
goto more;
}
if (sep->se_socktype != SOCK_STREAM) {
syslog(LOG_ERR,
"%s: bad socket type for tcpmux service %s",
CONFIG, sep->se_service);
goto more;
}
}
sep->se_user = newstr(sskip(&cp));
if ((sep->se_group = strchr(sep->se_user, ':')) != NULL)
*sep->se_group++ = '\0';
else if ((sep->se_group = strchr(sep->se_user, '.')) != NULL)
*sep->se_group++ = '\0';
sep->se_server = newstr(sskip(&cp));
if (strcmp(sep->se_server, "internal") == 0) {
struct biltin *bi;
for (bi = biltins; bi->bi_service; bi++)
if (bi->bi_socktype == sep->se_socktype &&
strcmp(bi->bi_service, sep->se_service) == 0)
break;
if (bi->bi_service == 0) {
syslog(LOG_ERR, "internal service %s unknown",
sep->se_service);
goto more;
}
sep->se_bi = bi;
sep->se_wait = bi->bi_wait;
} else
sep->se_bi = NULL;
argc = 0;
for (arg = skip(&cp); cp; arg = skip(&cp)) {
#if MULOG
char *colon;
if (argc == 0 && (colon = strrchr(arg, ':'))) {
while (arg < colon) {
int x;
char *ccp;
switch (*arg++) {
case 'l':
x = 1;
if (isdigit(*arg)) {
x = strtol(arg, &ccp, 0);
if (ccp == arg)
break;
arg = ccp;
}
sep->se_log &= ~MULOG_RFC931;
sep->se_log |= x;
break;
case 'a':
sep->se_log |= MULOG_RFC931;
break;
default:
break;
}
}
arg = colon + 1;
}
#endif
if (argc < MAXARGV)
sep->se_argv[argc++] = newstr(arg);
}
while (argc <= MAXARGV)
sep->se_argv[argc++] = NULL;
#ifdef IPSEC
sep->se_policy = policy ? newstr(policy) : NULL;
#endif
return (sep);
}
static void
freeconfig(struct servtab *cp)
{
int i;
if (cp->se_hostaddr)
free(cp->se_hostaddr);
if (cp->se_service)
free(cp->se_service);
if (cp->se_proto)
free(cp->se_proto);
if (cp->se_user)
free(cp->se_user);
/* Note: se_group is part of the newstr'ed se_user */
if (cp->se_server)
free(cp->se_server);
for (i = 0; i < MAXARGV; i++)
if (cp->se_argv[i])
free(cp->se_argv[i]);
#ifdef IPSEC
if (cp->se_policy)
free(cp->se_policy);
#endif
}
/*
* Safe skip - if skip returns null, log a syntax error in the
* configuration file and exit.
*/
static char *
sskip(char **cpp)
{
char *cp;
cp = skip(cpp);
if (cp == NULL) {
syslog(LOG_ERR, "%s: syntax error", CONFIG);
exit(1);
}
return (cp);
}
static char *
skip(char **cpp)
{
char *cp = *cpp;
char *start;
char quote;
if (*cpp == NULL)
return (NULL);
again:
while (*cp == ' ' || *cp == '\t')
cp++;
if (*cp == '\0') {
int c;
c = getc(fconfig);
(void) ungetc(c, fconfig);
if (c == ' ' || c == '\t')
if ((cp = nextline(fconfig)))
goto again;
*cpp = NULL;
return (NULL);
}
start = cp;
quote = '\0';
while (*cp && (quote || (*cp != ' ' && *cp != '\t'))) {
if (*cp == '\'' || *cp == '"') {
if (quote && *cp != quote)
cp++;
else {
if (quote)
quote = '\0';
else
quote = *cp;
memmove(cp, cp+1, strlen(cp));
}
} else
cp++;
}
if (*cp != '\0')
*cp++ = '\0';
*cpp = cp;
return (start);
}
static char *
nextline(FILE *fd)
{
char *cp;
if (fgets(line, sizeof (line), fd) == NULL)
return (NULL);
cp = strchr(line, '\n');
if (cp)
*cp = '\0';
return (line);
}
static char *
newstr(char *cp)
{
if ((cp = strdup((cp != NULL) ? cp : "")) != NULL)
return (cp);
syslog(LOG_ERR, "strdup: %m");
exit(1);
}
static void
inetd_setproctitle(char *a, int s)
{
socklen_t size;
struct sockaddr_storage ss;
char hbuf[NI_MAXHOST], *hp;
size = sizeof(ss);
if (getpeername(s, (struct sockaddr *)&ss, &size) == 0) {
if (getnameinfo((struct sockaddr *)&ss, size, hp = hbuf,
sizeof(hbuf), NULL, 0, niflags) != 0)
hp = "?";
setproctitle("-%s [%s]", a, hp);
} else
setproctitle("-%s", a);
}
static void
bump_nofile(void)
{
#ifdef RLIMIT_NOFILE
#define FD_CHUNK 32
struct rlimit rl;
if (getrlimit(RLIMIT_NOFILE, &rl) < 0) {
syslog(LOG_ERR, "getrlimit: %m");
return;
}
rl.rlim_cur = MIN(rl.rlim_max, rl.rlim_cur + FD_CHUNK);
if (rl.rlim_cur <= rlim_ofile_cur) {
syslog(LOG_ERR,
"bump_nofile: cannot extend file limit, max = %d",
(int)rl.rlim_cur);
return;
}
if (setrlimit(RLIMIT_NOFILE, &rl) < 0) {
syslog(LOG_ERR, "setrlimit: %m");
return;
}
rlim_ofile_cur = rl.rlim_cur;
return;
#else
syslog(LOG_ERR, "bump_nofile: cannot extend file limit");
return;
#endif
}
/*
* Internet services provided internally by inetd:
*/
#define BUFSIZE 4096
/* ARGSUSED */
static void
echo_stream(int s, struct servtab *sep) /* Echo service -- echo data back */
{
char buffer[BUFSIZE];
int i;
inetd_setproctitle(sep->se_service, s);
while ((i = read(s, buffer, sizeof(buffer))) > 0 &&
write(s, buffer, i) > 0)
;
}
/* ARGSUSED */
static void
echo_dg(int s, struct servtab *sep) /* Echo service -- echo data back */
{
char buffer[BUFSIZE];
int i;
socklen_t size;
struct sockaddr_storage ss;
struct sockaddr *sa;
sa = (struct sockaddr *)&ss;
size = sizeof(ss);
if ((i = recvfrom(s, buffer, sizeof(buffer), 0, sa, &size)) < 0)
return;
if (port_good_dg(sa))
(void) sendto(s, buffer, i, 0, sa, size);
}
/* ARGSUSED */
static void
discard_stream(int s, struct servtab *sep) /* Discard service -- ignore data */
{
char buffer[BUFSIZE];
inetd_setproctitle(sep->se_service, s);
while ((errno = 0, read(s, buffer, sizeof(buffer)) > 0) ||
errno == EINTR)
;
}
/* ARGSUSED */
static void
discard_dg(int s, struct servtab *sep) /* Discard service -- ignore data */
{
char buffer[BUFSIZE];
(void) read(s, buffer, sizeof(buffer));
}
#define LINESIZ 72
char ring[128];
char *endring;
static void
initring(void)
{
int i;
endring = ring;
for (i = 0; i <= 128; ++i)
if (isprint(i))
*endring++ = i;
}
/* ARGSUSED */
static void
chargen_stream(int s,struct servtab *sep) /* Character generator */
{
int len;
char *rs, text[LINESIZ+2];
inetd_setproctitle(sep->se_service, s);
if (!endring) {
initring();
rs = ring;
}
text[LINESIZ] = '\r';
text[LINESIZ + 1] = '\n';
for (rs = ring;;) {
if ((len = endring - rs) >= LINESIZ)
memmove(text, rs, LINESIZ);
else {
memmove(text, rs, len);
memmove(text + len, ring, LINESIZ - len);
}
if (++rs == endring)
rs = ring;
if (write(s, text, sizeof(text)) != sizeof(text))
break;
}
}
/* ARGSUSED */
static void
chargen_dg(int s, struct servtab *sep) /* Character generator */
{
struct sockaddr_storage ss;
struct sockaddr *sa;
static char *rs;
int len;
socklen_t size;
char text[LINESIZ+2];
if (endring == 0) {
initring();
rs = ring;
}
sa = (struct sockaddr *)&ss;
size = sizeof(ss);
if (recvfrom(s, text, sizeof(text), 0, sa, &size) < 0)
return;
if (!port_good_dg(sa))
return;
if ((len = endring - rs) >= LINESIZ)
memmove(text, rs, LINESIZ);
else {
memmove(text, rs, len);
memmove(text + len, ring, LINESIZ - len);
}
if (++rs == endring)
rs = ring;
text[LINESIZ] = '\r';
text[LINESIZ + 1] = '\n';
(void) sendto(s, text, sizeof(text), 0, sa, size);
}
/*
* Return a machine readable date and time, in the form of the
* number of seconds since midnight, Jan 1, 1900. Since gettimeofday
* returns the number of seconds since midnight, Jan 1, 1970,
* we must add 2208988800 seconds to this figure to make up for
* some seventy years Bell Labs was asleep.
*/
static uint32_t
machtime(void)
{
struct timeval tv;
if (gettimeofday(&tv, NULL) < 0) {
if (debug)
fprintf(stderr, "Unable to get time of day\n");
return (0);
}
#define OFFSET ((uint32_t)25567 * 24*60*60)
return (htonl((uint32_t)(tv.tv_sec + OFFSET)));
#undef OFFSET
}
/* ARGSUSED */
static void
machtime_stream(int s, struct servtab *sep)
{
uint32_t result;
result = machtime();
(void) write(s, (char *) &result, sizeof(result));
}
/* ARGSUSED */
void
machtime_dg(int s, struct servtab *sep)
{
uint32_t result;
struct sockaddr_storage ss;
struct sockaddr *sa;
socklen_t size;
sa = (struct sockaddr *)&ss;
size = sizeof(ss);
if (recvfrom(s, (char *)&result, sizeof(result), 0, sa, &size) < 0)
return;
if (!port_good_dg(sa))
return;
result = machtime();
(void) sendto(s, (char *) &result, sizeof(result), 0, sa, size);
}
/* ARGSUSED */
static void
daytime_stream(int s,struct servtab *sep)
/* Return human-readable time of day */
{
char buffer[256];
time_t clock;
int len;
clock = time((time_t *) 0);
len = snprintf(buffer, sizeof buffer, "%.24s\r\n", ctime(&clock));
(void) write(s, buffer, len);
}
/* ARGSUSED */
void
daytime_dg(int s, struct servtab *sep)
/* Return human-readable time of day */
{
char buffer[256];
time_t clock;
struct sockaddr_storage ss;
struct sockaddr *sa;
socklen_t size;
int len;
clock = time((time_t *) 0);
sa = (struct sockaddr *)&ss;
size = sizeof(ss);
if (recvfrom(s, buffer, sizeof(buffer), 0, sa, &size) < 0)
return;
if (!port_good_dg(sa))
return;
len = snprintf(buffer, sizeof buffer, "%.24s\r\n", ctime(&clock));
(void) sendto(s, buffer, len, 0, sa, size);
}
/*
* print_service:
* Dump relevant information to stderr
*/
static void
print_service(char *action, struct servtab *sep)
{
if (isrpcservice(sep))
fprintf(stderr,
"%s: %s rpcprog=%d, rpcvers = %d/%d, proto=%s, wait.max=%d.%d, user:group=%s:%s builtin=%lx server=%s"
#ifdef IPSEC
" policy=\"%s\""
#endif
"\n",
action, sep->se_service,
sep->se_rpcprog, sep->se_rpcversh, sep->se_rpcversl, sep->se_proto,
sep->se_wait, sep->se_max, sep->se_user, sep->se_group,
(long)sep->se_bi, sep->se_server
#ifdef IPSEC
, (sep->se_policy ? sep->se_policy : "")
#endif
);
else
fprintf(stderr,
"%s: %s proto=%s%s, wait.max=%d.%d, user:group=%s:%s builtin=%lx server=%s"
#ifdef IPSEC
" policy=%s"
#endif
"\n",
action, sep->se_service,
sep->se_type == FAITH_TYPE ? "faith/" : "",
sep->se_proto,
sep->se_wait, sep->se_max, sep->se_user, sep->se_group,
(long)sep->se_bi, sep->se_server
#ifdef IPSEC
, (sep->se_policy ? sep->se_policy : "")
#endif
);
}
static void
usage(void)
{
#ifdef LIBWRAP
(void)fprintf(stderr, "usage: %s [-dl] [conf]\n", getprogname());
#else
(void)fprintf(stderr, "usage: %s [-d] [conf]\n", getprogname());
#endif
exit(1);
}
/*
* Based on TCPMUX.C by Mark K. Lottor November 1988
* sri-nic::ps:<mkl>tcpmux.c
*/
static int /* # of characters upto \r,\n or \0 */
getline(int fd, char *buf, int len)
{
int count = 0, n;
do {
n = read(fd, buf, len-count);
if (n == 0)
return (count);
if (n < 0)
return (-1);
while (--n >= 0) {
if (*buf == '\r' || *buf == '\n' || *buf == '\0')
return (count);
count++;
buf++;
}
} while (count < len);
return (count);
}
#define MAX_SERV_LEN (256+2) /* 2 bytes for \r\n */
#define strwrite(fd, buf) (void) write(fd, buf, sizeof(buf)-1)
static void
tcpmux(int ctrl, struct servtab *sep)
{
char service[MAX_SERV_LEN+1];
int len;
/* Get requested service name */
if ((len = getline(ctrl, service, MAX_SERV_LEN)) < 0) {
strwrite(ctrl, "-Error reading service name\r\n");
goto reject;
}
service[len] = '\0';
if (debug)
fprintf(stderr, "tcpmux: someone wants %s\n", service);
/*
* Help is a required command, and lists available services,
* one per line.
*/
if (!strcasecmp(service, "help")) {
strwrite(ctrl, "+Available services:\r\n");
strwrite(ctrl, "help\r\n");
for (sep = servtab; sep != NULL; sep = sep->se_next) {
if (!ISMUX(sep))
continue;
(void)write(ctrl, sep->se_service,
strlen(sep->se_service));
strwrite(ctrl, "\r\n");
}
goto reject;
}
/* Try matching a service in inetd.conf with the request */
for (sep = servtab; sep != NULL; sep = sep->se_next) {
if (!ISMUX(sep))
continue;
if (!strcasecmp(service, sep->se_service)) {
if (ISMUXPLUS(sep))
strwrite(ctrl, "+Go\r\n");
run_service(ctrl, sep, 1 /* forked */);
return;
}
}
strwrite(ctrl, "-Service not available\r\n");
reject:
_exit(1);
}
#ifdef MULOG
void
dolog(struct servtab *sep, int ctrl)
{
struct sockaddr_storage ss;
struct sockaddr *sa = (struct sockaddr *)&ss;
socklen_t len = sizeof(ss);
char *host, *dp, buf[BUFSIZ];
int connected = 1;
switch (sep->se_family) {
case AF_INET:
#ifdef INET6
case AF_INET6:
#endif
break;
default:
return;
}
if (getpeername(ctrl, sa, &len) < 0) {
if (errno != ENOTCONN) {
syslog(LOG_ERR, "getpeername: %m");
return;
}
if (recvfrom(ctrl, buf, sizeof(buf), MSG_PEEK, sa, &len) < 0) {
syslog(LOG_ERR, "recvfrom: %m");
return;
}
connected = 0;
}
switch (sa->sa_family) {
case AF_INET:
#ifdef INET6
case AF_INET6:
#endif
break;
default:
syslog(LOG_ERR, "unexpected address family %u", sa->sa_family);
return;
}
if (getnameinfo(sa, len, buf, sizeof(buf), NULL, 0, 0) != 0)
strlcpy(buf, "?", sizeof(buf));
host = buf;
switch (sep->se_log & ~MULOG_RFC931) {
case 0:
return;
case 1:
if (curdom == NULL || *curdom == '\0')
break;
dp = host + strlen(host) - strlen(curdom);
if (dp < host)
break;
if (debug)
fprintf(stderr, "check \"%s\" against curdom \"%s\"\n",
host, curdom);
if (strcasecmp(dp, curdom) == 0)
return;
break;
case 2:
default:
break;
}
openlog("", LOG_NOWAIT, MULOG);
if (connected && (sep->se_log & MULOG_RFC931))
syslog(LOG_INFO, "%s@%s wants %s",
rfc931_name(sa, ctrl), host, sep->se_service);
else
syslog(LOG_INFO, "%s wants %s",
host, sep->se_service);
}
/*
* From tcp_log by
* Wietse Venema, Eindhoven University of Technology, The Netherlands.
*/
#if 0
static char sccsid[] = "@(#) rfc931.c 1.3 92/08/31 22:54:46";
#endif
#include <setjmp.h>
#define RFC931_PORT 113 /* Semi-well-known port */
#define TIMEOUT 4
#define TIMEOUT2 10
static jmp_buf timebuf;
/* timeout - handle timeouts */
static void
timeout(int sig)
{
longjmp(timebuf, sig);
}
/* rfc931_name - return remote user name */
char *
rfc931_name(struct sockaddr *there, /* remote link information */
int ctrl)
{
struct sockaddr_storage here; /* local link information */
struct sockaddr_storage sin; /* for talking to RFC931 daemon */
socklen_t length;
int s;
unsigned remote;
unsigned local;
static char user[256]; /* XXX */
char buf[256];
char *cp;
char *result = "USER_UNKNOWN";
int len;
u_int16_t myport, hisport;
/* Find out local port number of our stdin. */
length = sizeof(here);
if (getsockname(ctrl, (struct sockaddr *) &here, &length) == -1) {
syslog(LOG_ERR, "getsockname: %m");
return (result);
}
switch (here.ss_family) {
case AF_INET:
myport = ((struct sockaddr_in *)&here)->sin_port;
break;
#ifdef INET6
case AF_INET6:
myport = ((struct sockaddr_in6 *)&here)->sin6_port;
break;
#endif
}
switch (there->sa_family) {
case AF_INET:
hisport = ((struct sockaddr_in *)&there)->sin_port;
break;
#ifdef INET6
case AF_INET6:
hisport = ((struct sockaddr_in6 *)&there)->sin6_port;
break;
#endif
}
/* Set up timer so we won't get stuck. */
if ((s = socket(here.ss_family, SOCK_STREAM, 0)) == -1) {
syslog(LOG_ERR, "socket: %m");
return (result);
}
sin = here;
switch (sin.ss_family) {
case AF_INET:
((struct sockaddr_in *)&sin)->sin_port = htons(0);
break;
#ifdef INET6
case AF_INET6:
((struct sockaddr_in6 *)&sin)->sin6_port = htons(0);
break;
#endif
}
if (bind(s, (struct sockaddr *) &sin, sin.ss_len) == -1) {
syslog(LOG_ERR, "bind: %m");
return (result);
}
signal(SIGALRM, timeout);
if (setjmp(timebuf)) {
close(s); /* not: fclose(fp) */
return (result);
}
alarm(TIMEOUT);
/* Connect to the RFC931 daemon. */
memcpy(&sin, there, there->sa_len);
switch (sin.ss_family) {
case AF_INET:
((struct sockaddr_in *)&sin)->sin_port = htons(RFC931_PORT);
break;
#ifdef INET6
case AF_INET6:
((struct sockaddr_in6 *)&sin)->sin6_port = htons(RFC931_PORT);
break;
#endif
}
if (connect(s, (struct sockaddr *) &sin, sin.ss_len) == -1) {
close(s);
alarm(0);
return (result);
}
/* Query the RFC 931 server. Would 13-byte writes ever be broken up? */
(void)snprintf(buf, sizeof buf, "%u,%u\r\n", ntohs(hisport),
ntohs(myport));
for (len = 0, cp = buf; len < strlen(buf); ) {
int n;
if ((n = write(s, cp, strlen(buf) - len)) == -1) {
close(s);
alarm(0);
return (result);
}
cp += n;
len += n;
}
/* Read response */
for (cp = buf; cp < buf + sizeof(buf) - 1; ) {
char c;
if (read(s, &c, 1) != 1) {
close(s);
alarm(0);
return (result);
}
if (c == '\n')
break;
*cp++ = c;
}
*cp = '\0';
if (sscanf(buf, "%u , %u : USERID :%*[^:]:%255s", &remote, &local,
user) == 3 && ntohs(hisport) == remote && ntohs(myport) == local) {
/* Strip trailing carriage return. */
if ((cp = strchr(user, '\r')) != NULL)
*cp = 0;
result = user;
}
alarm(0);
close(s);
return (result);
}
#endif
/*
* check if the address/port where send data to is one of the obvious ports
* that are used for denial of service attacks like two echo ports
* just echoing data between them
*/
static int
port_good_dg(struct sockaddr *sa)
{
struct in_addr in;
#ifdef INET6
struct in6_addr *in6;
#endif
u_int16_t port;
int i, bad;
char hbuf[NI_MAXHOST];
bad = 0;
switch (sa->sa_family) {
case AF_INET:
in.s_addr = ntohl(((struct sockaddr_in *)sa)->sin_addr.s_addr);
port = ntohs(((struct sockaddr_in *)sa)->sin_port);
#ifdef INET6
v4chk:
#endif
if (IN_MULTICAST(in.s_addr))
goto bad;
switch ((in.s_addr & 0xff000000) >> 24) {
case 0: case 127: case 255:
goto bad;
}
if (dg_broadcast(&in))
goto bad;
break;
#ifdef INET6
case AF_INET6:
in6 = &((struct sockaddr_in6 *)sa)->sin6_addr;
port = ntohs(((struct sockaddr_in6 *)sa)->sin6_port);
if (IN6_IS_ADDR_MULTICAST(in6) || IN6_IS_ADDR_UNSPECIFIED(in6))
goto bad;
if (IN6_IS_ADDR_V4MAPPED(in6) || IN6_IS_ADDR_V4COMPAT(in6)) {
memcpy(&in, &in6->s6_addr[12], sizeof(in));
in.s_addr = ntohl(in.s_addr);
goto v4chk;
}
break;
#endif
default:
/* XXX unsupported af, is it safe to assume it to be safe? */
return (1);
}
for (i = 0; bad_ports[i] != 0; i++) {
if (port == bad_ports[i])
goto bad;
}
return (1);
bad:
if (getnameinfo(sa, sa->sa_len, hbuf, sizeof(hbuf), NULL, 0,
niflags) != 0)
strlcpy(hbuf, "?", sizeof(hbuf));
syslog(LOG_WARNING,"Possible DoS attack from %s, Port %d",
hbuf, port);
return (0);
}
/* XXX need optimization */
static int
dg_broadcast(struct in_addr *in)
{
struct ifaddrs *ifa, *ifap;
struct sockaddr_in *sin;
if (getifaddrs(&ifap) < 0)
return (0);
for (ifa = ifap; ifa; ifa = ifa->ifa_next) {
if (ifa->ifa_addr->sa_family != AF_INET ||
(ifa->ifa_flags & IFF_BROADCAST) == 0)
continue;
sin = (struct sockaddr_in *)ifa->ifa_broadaddr;
if (sin->sin_addr.s_addr == in->s_addr) {
freeifaddrs(ifap);
return (1);
}
}
freeifaddrs(ifap);
return (0);
}
static int
my_kevent(const struct kevent *changelist, size_t nchanges,
struct kevent *eventlist, size_t nevents)
{
int result;
while ((result = kevent(kq, changelist, nchanges, eventlist, nevents,
NULL)) < 0)
if (errno != EINTR) {
syslog(LOG_ERR, "kevent: %m");
exit(EXIT_FAILURE);
}
return (result);
}
static struct kevent *
allocchange(void)
{
if (changes == A_CNT(changebuf)) {
(void) my_kevent(changebuf, A_CNT(changebuf), NULL, 0);
changes = 0;
}
return (&changebuf[changes++]);
}
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