emo/busybox
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity
feb7ae7f01
busybox/networking/inetd.c
Denis Vlasenko 0c97c9d437 'simple' error message functions by Loic Grenie <loic.grenie@gmail.com>. 
263 bytes saved.
2007-10-01 11:58:38 +00:00

1837 lines
48 KiB
C
Raw Blame History

/* vi: set sw=4 ts=4: */
/* $Slackware: inetd.c 1.79s 2001/02/06 13:18:00 volkerdi Exp $ */
/* $OpenBSD: inetd.c,v 1.79 2001/01/30 08:30:57 deraadt Exp $ */
/* $NetBSD: inetd.c,v 1.11 1996/02/22 11:14:41 mycroft Exp $ */
/* Busybox port by Vladimir Oleynik (C) 2001-2005 <dzo@simtreas.ru> */
/*
* Copyright (c) 1983,1991 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.
*/
/* 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
* socket type stream/dgram/raw/rdm/seqpacket
* protocol must be in /etc/protocols
* wait/nowait[.max] single-threaded/multi-threaded, max #
* user[.group] or 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] or 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.
*
* Comment lines are indicated by a `#' in column 1.
*/
/* inetd rules for passing file descriptors to children
* (http://www.freebsd.org/cgi/man.cgi?query=inetd):
*
* The wait/nowait entry specifies whether the server that is invoked by
* inetd will take over the socket associated with the service access point,
* and thus whether inetd should wait for the server to exit before listen-
* ing for new service requests. Datagram servers must use "wait", as
* they are always invoked with the original datagram socket bound to the
* specified service address. These servers must read at least one datagram
* from the socket before exiting. If a datagram server connects to its
* peer, freeing the socket so inetd can receive further messages on the
* socket, it is said to be a "multi-threaded" server; it should read one
* datagram from the socket and create a new socket connected to the peer.
* It should fork, and the parent should then exit to allow inetd to check
* for new service requests to spawn new servers. Datagram servers which
* process all incoming datagrams on a socket and eventually time out are
* said to be "single-threaded". The comsat(8), (biff(1)) and talkd(8)
* utilities are both examples of the latter type of datagram server. The
* tftpd(8) utility is an example of a multi-threaded datagram server.
*
* Servers using stream sockets generally are multi-threaded and use the
* "nowait" entry. Connection requests for these services are accepted by
* inetd, and the server is given only the newly-accepted socket connected
* to a client of the service. Most stream-based services operate in this
* manner. Stream-based servers that use "wait" are started with the lis-
* tening service socket, and must accept at least one connection request
* before exiting. Such a server would normally accept and process incoming
* connection requests until a timeout.
*/
/* 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: setgid(primary group as found in passwd)
* initgroups(name, primary group)
* setuid()
*
* 2) set-group-option on.
*
* a) user = root: setgid(specified group)
* NO initgroups()
* NO setuid()
*
* b) other: setgid(specified group)
* initgroups(name, specified group)
* setuid()
*/
#include "libbb.h"
#include <syslog.h>
#include <sys/un.h>
//#define ENABLE_FEATURE_INETD_RPC 1
//#define ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_ECHO 1
//#define ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_DISCARD 1
//#define ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_TIME 1
//#define ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_DAYTIME 1
//#define ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_CHARGEN 1
//#define ENABLE_FEATURE_IPV6 1
#if ENABLE_FEATURE_INETD_RPC
#include <rpc/rpc.h>
#include <rpc/pmap_clnt.h>
#endif
extern char **environ;
#define _PATH_INETDPID "/var/run/inetd.pid"
#define CNT_INTVL 60 /* servers in CNT_INTVL sec. */
#define RETRYTIME (60*10) /* retry after bind or server fail */
#ifndef RLIMIT_NOFILE
#define RLIMIT_NOFILE RLIMIT_OFILE
#endif
#ifndef OPEN_MAX
#define OPEN_MAX 64
#endif
/* Reserve some descriptors, 3 stdio + at least: 1 log, 1 conf. file */
#define FD_MARGIN 8
/* Check unsupporting builtin */
#if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_ECHO || \
ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_DISCARD || \
ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_TIME || \
ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_DAYTIME || \
ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_CHARGEN
# define INETD_FEATURE_ENABLED
#endif
#if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_ECHO || \
ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_DISCARD || \
ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_CHARGEN
# define INETD_SETPROCTITLE
#endif
typedef int8_t socktype_t;
typedef int8_t family_t;
struct BUG_too_small {
char BUG_socktype_t_too_small[(0
| SOCK_STREAM
| SOCK_DGRAM
| SOCK_RDM
| SOCK_SEQPACKET
| SOCK_RAW) <= 127 ? 1 : -1];
char BUG_family_t_too_small[(0
| AF_INET
| AF_INET6
| AF_UNIX) <= 127 ? 1 : -1];
};
typedef struct servtab_t {
/* The most frequently referenced one: */
int se_fd; /* open descriptor */
/* NB: 'biggest fields last' saves on code size (~250 bytes) */
char *se_hostaddr; /* host address to listen on */
char *se_service; /* name of service */
char *se_proto; /* protocol used */
#if ENABLE_FEATURE_INETD_RPC
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)
#else
#define isrpcservice(sep) 0
#endif
pid_t se_wait; /* single threaded server */
socktype_t se_socktype; /* type of socket to use */
family_t se_family; /* address family */
smallint se_checked; /* looked at during merge */
char *se_user; /* user name to run as */
char *se_group; /* group name to run as */
#ifdef INETD_FEATURE_ENABLED
const struct builtin *se_bi; /* if built-in, description */
#endif
int se_ctrladdr_size;
int se_max; /* max # of instances of this service */
int se_count; /* number started since se_time */
struct servtab_t *se_next;
struct timeval se_time; /* start of se_count */
char *se_server; /* server program */
#define MAXARGV 20
char *se_argv[MAXARGV + 1]; /* program arguments */
union {
struct sockaddr se_un_ctrladdr;
struct sockaddr_in se_un_ctrladdr_in;
#if ENABLE_FEATURE_IPV6
struct sockaddr_in6 se_un_ctrladdr_in6;
#endif
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_in6 se_un.se_un_ctrladdr_in6
#define se_ctrladdr_un se_un.se_un_ctrladdr_un
} servtab_t;
#ifdef INETD_FEATURE_ENABLED
struct builtin {
const char *bi_service; /* internally provided service name */
socktype_t bi_socktype; /* type of socket supported */
uint8_t bi_fork; /* 1 if should fork before call */
// Commented since it is always 0
// uint8_t bi_wait; /* 1 if should wait for child */
void (*bi_fn) (int, servtab_t *);
};
/* Echo received data */
#if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_ECHO
static void echo_stream(int, servtab_t *);
static void echo_dg(int, servtab_t *);
#endif
/* Internet /dev/null */
#if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_DISCARD
static void discard_stream(int, servtab_t *);
static void discard_dg(int, servtab_t *);
#endif
/* Return 32 bit time since 1900 */
#if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_TIME
static void machtime_stream(int, servtab_t *);
static void machtime_dg(int, servtab_t *);
#endif
/* Return human-readable time */
#if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_DAYTIME
static void daytime_stream(int, servtab_t *);
static void daytime_dg(int, servtab_t *);
#endif
/* Familiar character generator */
#if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_CHARGEN
static void chargen_stream(int, servtab_t *);
static void chargen_dg(int, servtab_t *);
#endif
static const struct builtin builtins[] = {
#if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_ECHO
/* Echo received data */
{"echo", SOCK_STREAM, 1, echo_stream,},
{"echo", SOCK_DGRAM, 0, echo_dg,},
#endif
#if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_DISCARD
/* Internet /dev/null */
{"discard", SOCK_STREAM, 1, discard_stream,},
{"discard", SOCK_DGRAM, 0, discard_dg,},
#endif
#if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_TIME
/* Return 32 bit time since 1900 */
{"time", SOCK_STREAM, 0, machtime_stream,},
{"time", SOCK_DGRAM, 0, machtime_dg,},
#endif
#if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_DAYTIME
/* Return human-readable time */
{"daytime", SOCK_STREAM, 0, daytime_stream,},
{"daytime", SOCK_DGRAM, 0, daytime_dg,},
#endif
#if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_CHARGEN
/* Familiar character generator */
{"chargen", SOCK_STREAM, 1, chargen_stream,},
{"chargen", SOCK_DGRAM, 0, chargen_dg,},
#endif
{ /* zero filled */ }
};
#endif /* INETD_FEATURE_ENABLED */
struct globals {
rlim_t rlim_ofile_cur;
struct rlimit rlim_ofile;
servtab_t *servtab;
int global_queuelen;
int nsock;
int maxsock;
int toomany;
int timingout;
struct servent *sp;
uid_t uid;
const char *config_filename;
FILE *fconfig;
char *defhost;
#ifdef INETD_SETPROCTITLE
char **Argv;
char *LastArg;
#endif
#if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_CHARGEN
char *endring;
char *ringpos;
char ring[128];
#endif
fd_set allsock;
/* Used only in nextline() */
char line[80]; /* at least 80, see LINE_SIZE */
};
#define G (*(struct globals*)&bb_common_bufsiz1)
enum { LINE_SIZE = COMMON_BUFSIZE - offsetof(struct globals, line) };
struct BUG_G_too_big {
char BUG_G_too_big[sizeof(G) <= COMMON_BUFSIZE ? 1 : -1];
};
#define rlim_ofile_cur (G.rlim_ofile_cur )
#define rlim_ofile (G.rlim_ofile )
#define servtab (G.servtab )
#define global_queuelen (G.global_queuelen)
#define nsock (G.nsock )
#define maxsock (G.maxsock )
#define toomany (G.toomany )
#define timingout (G.timingout )
#define sp (G.sp )
#define uid (G.uid )
#define config_filename (G.config_filename)
#define fconfig (G.fconfig )
#define defhost (G.defhost )
#define Argv (G.Argv )
#define LastArg (G.LastArg )
#define endring (G.endring )
#define ringpos (G.ringpos )
#define ring (G.ring )
#define allsock (G.allsock )
#define line (G.line )
#define INIT_G() do { \
rlim_ofile_cur = OPEN_MAX; \
global_queuelen = 128; \
config_filename = "/etc/inetd.conf"; \
} while (0)
/* xstrdup(NULL) returns NULL, but this one
* will return newly-allocated "" if called with NULL arg
* TODO: audit whether this makes any real difference
*/
static char *xxstrdup(char *cp)
{
return xstrdup(cp ? cp : "");
}
static int setconfig(void)
{
free(defhost);
defhost = xstrdup("*");
if (fconfig != NULL) {
fseek(fconfig, 0L, SEEK_SET);
return 1;
}
fconfig = fopen(config_filename, "r");
return (fconfig != NULL);
}
static void endconfig(void)
{
if (fconfig) {
(void) fclose(fconfig);
fconfig = NULL;
}
free(defhost);
defhost = 0;
}
#if ENABLE_FEATURE_INETD_RPC
static void register_rpc(servtab_t *sep)
{
int n;
struct sockaddr_in ir_sin;
struct protoent *pp;
socklen_t size;
if ((pp = getprotobyname(sep->se_proto + 4)) == NULL) {
bb_perror_msg("%s: getproto", sep->se_proto);
return;
}
size = sizeof ir_sin;
if (getsockname(sep->se_fd, (struct sockaddr *) &ir_sin, &size) < 0) {
bb_perror_msg("%s/%s: getsockname",
sep->se_service, sep->se_proto);
return;
}
for (n = sep->se_rpcversl; n <= sep->se_rpcversh; n++) {
(void) pmap_unset(sep->se_rpcprog, n);
if (!pmap_set(sep->se_rpcprog, n, pp->p_proto, ntohs(ir_sin.sin_port)))
bb_perror_msg("%s %s: pmap_set: %u %u %u %u",
sep->se_service, sep->se_proto,
sep->se_rpcprog, n, pp->p_proto, ntohs(ir_sin.sin_port));
}
}
static void unregister_rpc(servtab_t *sep)
{
int n;
for (n = sep->se_rpcversl; n <= sep->se_rpcversh; n++) {
if (!pmap_unset(sep->se_rpcprog, n))
bb_error_msg("pmap_unset(%u, %u)", sep->se_rpcprog, n);
}
}
#endif /* FEATURE_INETD_RPC */
static void freeconfig(servtab_t *cp)
{
int i;
free(cp->se_hostaddr);
free(cp->se_service);
free(cp->se_proto);
free(cp->se_user);
free(cp->se_group);
free(cp->se_server);
for (i = 0; i < MAXARGV; i++)
free(cp->se_argv[i]);
}
static int bump_nofile(void)
{
#define FD_CHUNK 32
struct rlimit rl;
if (getrlimit(RLIMIT_NOFILE, &rl) < 0) {
bb_perror_msg("getrlimit");
return -1;
}
rl.rlim_cur = MIN(rl.rlim_max, rl.rlim_cur + FD_CHUNK);
rl.rlim_cur = MIN(FD_SETSIZE, rl.rlim_cur + FD_CHUNK);
if (rl.rlim_cur <= rlim_ofile_cur) {
bb_error_msg("bump_nofile: cannot extend file limit, max = %d",
(int) rl.rlim_cur);
return -1;
}
if (setrlimit(RLIMIT_NOFILE, &rl) < 0) {
bb_perror_msg("setrlimit");
return -1;
}
rlim_ofile_cur = rl.rlim_cur;
return 0;
}
static void setup(servtab_t *sep)
{
int r;
sep->se_fd = socket(sep->se_family, sep->se_socktype, 0);
if (sep->se_fd < 0) {
bb_perror_msg("%s/%s: socket", sep->se_service, sep->se_proto);
return;
}
setsockopt_reuseaddr(sep->se_fd);
#if ENABLE_FEATURE_INETD_RPC
if (isrpcservice(sep)) {
struct passwd *pwd;
/*
* for RPC services, attempt to use a reserved port
* if they are going to be running as root.
*
* Also, zero out the port for all RPC services; let bind()
* find one.
*/
sep->se_ctrladdr_in.sin_port = 0;
if (sep->se_user && (pwd = getpwnam(sep->se_user)) &&
pwd->pw_uid == 0 && uid == 0)
r = bindresvport(sep->se_fd, &sep->se_ctrladdr_in);
else {
r = bind(sep->se_fd, &sep->se_ctrladdr, sep->se_ctrladdr_size);
if (r == 0) {
socklen_t len = sep->se_ctrladdr_size;
int saveerrno = errno;
/* update se_ctrladdr_in.sin_port */
r = getsockname(sep->se_fd, &sep->se_ctrladdr, &len);
if (r <= 0)
errno = saveerrno;
}
}
} else
#endif
r = bind(sep->se_fd, &sep->se_ctrladdr, sep->se_ctrladdr_size);
if (r < 0) {
bb_perror_msg("%s/%s (%d): bind",
sep->se_service, sep->se_proto, sep->se_ctrladdr.sa_family);
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, global_queuelen);
FD_SET(sep->se_fd, &allsock);
nsock++;
if (sep->se_fd > maxsock) {
maxsock = sep->se_fd;
if ((rlim_t)maxsock > rlim_ofile_cur - FD_MARGIN)
bump_nofile();
}
}
static char *nextline(void)
{
char *cp;
FILE *fd = fconfig;
if (fgets(line, LINE_SIZE, fd) == NULL)
return NULL;
cp = strchr(line, '\n');
if (cp)
*cp = '\0';
return line;
}
static char *skip(char **cpp) /* int report; */
{
char *cp = *cpp;
char *start;
/* erp: */
if (*cpp == NULL) {
/* if (report) */
/* bb_error_msg("syntax error in inetd config file"); */
return NULL;
}
again:
while (*cp == ' ' || *cp == '\t')
cp++;
if (*cp == '\0') {
int c;
c = getc(fconfig);
ungetc(c, fconfig);
if (c == ' ' || c == '\t') {
cp = nextline();
if (cp)
goto again;
}
*cpp = NULL;
/* goto erp; */
return NULL;
}
start = cp;
while (*cp && *cp != ' ' && *cp != '\t')
cp++;
if (*cp != '\0')
*cp++ = '\0';
/* if ((*cpp = cp) == NULL) */
/* goto erp; */
*cpp = cp;
return start;
}
static servtab_t *new_servtab(void)
{
return xmalloc(sizeof(servtab_t));
}
static servtab_t *dupconfig(servtab_t *sep)
{
servtab_t *newtab;
int argc;
newtab = new_servtab();
memset(newtab, 0, sizeof(servtab_t));
newtab->se_service = xstrdup(sep->se_service);
newtab->se_socktype = sep->se_socktype;
newtab->se_family = sep->se_family;
newtab->se_proto = xstrdup(sep->se_proto);
#if ENABLE_FEATURE_INETD_RPC
newtab->se_rpcprog = sep->se_rpcprog;
newtab->se_rpcversl = sep->se_rpcversl;
newtab->se_rpcversh = sep->se_rpcversh;
#endif
newtab->se_wait = sep->se_wait;
newtab->se_user = xstrdup(sep->se_user);
newtab->se_group = xstrdup(sep->se_group);
#ifdef INETD_FEATURE_ENABLED
newtab->se_bi = sep->se_bi;
#endif
newtab->se_server = xstrdup(sep->se_server);
for (argc = 0; argc <= MAXARGV; argc++)
newtab->se_argv[argc] = xstrdup(sep->se_argv[argc]);
newtab->se_max = sep->se_max;
return newtab;
}
static servtab_t *getconfigent(void)
{
servtab_t *sep;
int argc;
char *cp, *arg;
char *hostdelim;
servtab_t *nsep;
servtab_t *psep;
sep = new_servtab();
/* memset(sep, 0, sizeof *sep); */
more:
/* freeconfig(sep); */
while ((cp = nextline()) && *cp == '#') /* skip comment line */;
if (cp == NULL) {
/* free(sep); */
return NULL;
}
memset((char *) sep, 0, sizeof *sep);
arg = skip(&cp);
if (arg == NULL) {
/* A blank line. */
goto more;
}
/* Check for a host name. */
hostdelim = strrchr(arg, ':');
if (hostdelim) {
*hostdelim = '\0';
sep->se_hostaddr = xstrdup(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 = xxstrdup(defhost);
sep->se_service = xxstrdup(arg);
arg = skip(&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;
sep->se_proto = xxstrdup(skip(&cp));
if (strcmp(sep->se_proto, "unix") == 0) {
sep->se_family = AF_UNIX;
} else {
sep->se_family = AF_INET;
if (sep->se_proto[strlen(sep->se_proto) - 1] == '6')
#if ENABLE_FEATURE_IPV6
sep->se_family = AF_INET6;
#else
bb_error_msg("%s: IPV6 not supported", sep->se_proto);
#endif
if (strncmp(sep->se_proto, "rpc/", 4) == 0) {
#if ENABLE_FEATURE_INETD_RPC
char *p, *ccp;
long l;
p = strchr(sep->se_service, '/');
if (p == 0) {
bb_error_msg("%s: no rpc version", sep->se_service);
goto more;
}
*p++ = '\0';
l = strtol(p, &ccp, 0);
if (ccp == p || l < 0 || l > INT_MAX) {
badafterall:
bb_error_msg("%s/%s: bad rpc version", sep->se_service, p);
goto more;
}
sep->se_rpcversl = sep->se_rpcversh = l;
if (*ccp == '-') {
p = ccp + 1;
l = strtol(p, &ccp, 0);
if (ccp == p || l < 0 || l > INT_MAX || l < sep->se_rpcversl || *ccp)
goto badafterall;
sep->se_rpcversh = l;
} else if (*ccp != '\0')
goto badafterall;
#else
bb_error_msg("%s: rpc services not supported", sep->se_service);
#endif
}
}
arg = skip(&cp);
if (arg == NULL)
goto more;
{
char *s = strchr(arg, '.');
if (s) {
*s++ = '\0';
sep->se_max = xatoi(s);
} else
sep->se_max = toomany;
}
sep->se_wait = strcmp(arg, "wait") == 0;
/* if ((arg = skip(&cp, 1)) == NULL) */
/* goto more; */
sep->se_user = xxstrdup(skip(&cp));
arg = strchr(sep->se_user, '.');
if (arg == NULL)
arg = strchr(sep->se_user, ':');
if (arg) {
*arg++ = '\0';
sep->se_group = xstrdup(arg);
}
/* if ((arg = skip(&cp, 1)) == NULL) */
/* goto more; */
sep->se_server = xxstrdup(skip(&cp));
if (strcmp(sep->se_server, "internal") == 0) {
#ifdef INETD_FEATURE_ENABLED
const struct builtin *bi;
for (bi = builtins; 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) {
bb_error_msg("internal service %s unknown", sep->se_service);
goto more;
}
sep->se_bi = bi;
sep->se_wait = 0; /* = bi->bi_wait; - always 0 */
#else
bb_perror_msg("internal service %s unknown", sep->se_service);
goto more;
#endif
}
#ifdef INETD_FEATURE_ENABLED
else
sep->se_bi = NULL;
#endif
argc = 0;
for (arg = skip(&cp); cp; arg = skip(&cp)) {
if (argc < MAXARGV)
sep->se_argv[argc++] = xxstrdup(arg);
}
while (argc <= MAXARGV)
sep->se_argv[argc++] = NULL;
/*
* Now that we've processed the entire line, check if the hostname
* specifier was a comma separated list of hostnames. If so
* we'll make new entries for each address.
*/
while ((hostdelim = strrchr(sep->se_hostaddr, ',')) != NULL) {
nsep = dupconfig(sep);
/*
* NULL terminate the hostname field of the existing entry,
* and make a dup for the new entry.
*/
*hostdelim++ = '\0';
nsep->se_hostaddr = xstrdup(hostdelim);
nsep->se_next = sep->se_next;
sep->se_next = nsep;
}
nsep = sep;
while (nsep != NULL) {
nsep->se_checked = 1;
if (nsep->se_family == AF_INET) {
if (LONE_CHAR(nsep->se_hostaddr, '*'))
nsep->se_ctrladdr_in.sin_addr.s_addr = INADDR_ANY;
else if (!inet_aton(nsep->se_hostaddr, &nsep->se_ctrladdr_in.sin_addr)) {
int i;
struct hostent *hp;
hp = gethostbyname(nsep->se_hostaddr);
if (hp == NULL) {
bb_error_msg("%s: unknown host", nsep->se_hostaddr);
nsep->se_checked = 0;
goto skip;
}
if (hp->h_addrtype != AF_INET) {
bb_error_msg("%s: address isn't an Internet "
"address", nsep->se_hostaddr);
nsep->se_checked = 0;
goto skip;
}
i = 1;
memmove(&nsep->se_ctrladdr_in.sin_addr,
hp->h_addr_list[0], sizeof(struct in_addr));
while (hp->h_addr_list[i] != NULL) {
psep = dupconfig(nsep);
psep->se_hostaddr = xxstrdup(nsep->se_hostaddr);
psep->se_checked = 1;
memmove(&psep->se_ctrladdr_in.sin_addr,
hp->h_addr_list[i], sizeof(struct in_addr));
psep->se_ctrladdr_size = sizeof(psep->se_ctrladdr_in);
i++;
/* Prepend to list, don't want to look up */
/* its hostname again. */
psep->se_next = sep;
sep = psep;
}
}
}
/* XXX BUG?: is this skip: label supposed to remain? */
skip:
nsep = nsep->se_next;
}
/*
* Finally, free any entries which failed the gethostbyname
* check.
*/
psep = NULL;
nsep = sep;
while (nsep != NULL) {
servtab_t *tsep;
if (nsep->se_checked == 0) {
tsep = nsep;
if (psep == NULL) {
sep = nsep->se_next;
nsep = sep;
} else {
nsep = nsep->se_next;
psep->se_next = nsep;
}
freeconfig(tsep);
} else {
nsep->se_checked = 0;
psep = nsep;
nsep = nsep->se_next;
}
}
return sep;
}
#define Block_Using_Signals(m) do { \
sigemptyset(&m); \
sigaddset(&m, SIGCHLD); \
sigaddset(&m, SIGHUP); \
sigaddset(&m, SIGALRM); \
sigprocmask(SIG_BLOCK, &m, NULL); \
} while (0)
static servtab_t *enter(servtab_t *cp)
{
servtab_t *sep;
sigset_t omask;
sep = new_servtab();
*sep = *cp;
sep->se_fd = -1;
#if ENABLE_FEATURE_INETD_RPC
sep->se_rpcprog = -1;
#endif
Block_Using_Signals(omask);
sep->se_next = servtab;
servtab = sep;
sigprocmask(SIG_UNBLOCK, &omask, NULL);
return sep;
}
static int matchconf(servtab_t *old, servtab_t *new)
{
if (strcmp(old->se_service, new->se_service) != 0)
return 0;
if (strcmp(old->se_hostaddr, new->se_hostaddr) != 0)
return 0;
if (strcmp(old->se_proto, new->se_proto) != 0)
return 0;
/*
* If the new servtab is bound to a specific address, check that the
* old servtab is bound to the same entry. If the new service is not
* bound to a specific address then the check of se_hostaddr above
* is sufficient.
*/
if (old->se_family == AF_INET && new->se_family == AF_INET &&
memcmp(&old->se_ctrladdr_in.sin_addr,
&new->se_ctrladdr_in.sin_addr,
sizeof(new->se_ctrladdr_in.sin_addr)) != 0)
return 0;
#if ENABLE_FEATURE_IPV6
if (old->se_family == AF_INET6 && new->se_family == AF_INET6 &&
memcmp(&old->se_ctrladdr_in6.sin6_addr,
&new->se_ctrladdr_in6.sin6_addr,
sizeof(new->se_ctrladdr_in6.sin6_addr)) != 0)
return 0;
#endif
return 1;
}
static void config(int sig ATTRIBUTE_UNUSED)
{
servtab_t *sep, *cp, **sepp;
sigset_t omask;
size_t n;
char protoname[10];
if (!setconfig()) {
bb_simple_perror_msg(config_filename);
return;
}
for (sep = servtab; sep; sep = sep->se_next)
sep->se_checked = 0;
cp = getconfigent();
while (cp != NULL) {
for (sep = servtab; sep; sep = sep->se_next)
if (matchconf(sep, cp))
break;
if (sep != 0) {
int i;
#define SWAP(type, a, b) do {type c=(type)a; a=(type)b; b=(type)c;} while (0)
Block_Using_Signals(omask);
/*
* 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 (
#ifdef INETD_FEATURE_ENABLED
cp->se_bi == 0 &&
#endif
(sep->se_wait == 1 || cp->se_wait == 0))
sep->se_wait = cp->se_wait;
SWAP(int, cp->se_max, sep->se_max);
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]);
#undef SWAP
#if ENABLE_FEATURE_INETD_RPC
if (isrpcservice(sep))
unregister_rpc(sep);
sep->se_rpcversl = cp->se_rpcversl;
sep->se_rpcversh = cp->se_rpcversh;
#endif
sigprocmask(SIG_UNBLOCK, &omask, NULL);
freeconfig(cp);
} else {
sep = enter(cp);
}
sep->se_checked = 1;
switch (sep->se_family) {
case AF_UNIX:
if (sep->se_fd != -1)
break;
(void) unlink(sep->se_service);
n = strlen(sep->se_service);
if (n > sizeof sep->se_ctrladdr_un.sun_path - 1)
n = sizeof sep->se_ctrladdr_un.sun_path - 1;
safe_strncpy(sep->se_ctrladdr_un.sun_path, sep->se_service, n + 1);
sep->se_ctrladdr_un.sun_family = AF_UNIX;
sep->se_ctrladdr_size = n + sizeof sep->se_ctrladdr_un.sun_family;
setup(sep);
break;
case AF_INET:
sep->se_ctrladdr_in.sin_family = AF_INET;
/* se_ctrladdr_in was set in getconfigent */
sep->se_ctrladdr_size = sizeof sep->se_ctrladdr_in;
#if ENABLE_FEATURE_INETD_RPC
if (isrpcservice(sep)) {
struct rpcent *rp;
// FIXME: atoi_or_else(str, 0) would be handy here
sep->se_rpcprog = atoi(sep->se_service);
if (sep->se_rpcprog == 0) {
rp = getrpcbyname(sep->se_service);
if (rp == 0) {
bb_error_msg("%s: unknown rpc service", sep->se_service);
goto serv_unknown;
}
sep->se_rpcprog = rp->r_number;
}
if (sep->se_fd == -1)
setup(sep);
if (sep->se_fd != -1)
register_rpc(sep);
} else
#endif
{
uint16_t port = htons(atoi(sep->se_service));
// FIXME: atoi_or_else(str, 0) would be handy here
if (!port) {
/*XXX*/ strncpy(protoname, sep->se_proto, sizeof(protoname));
if (isdigit(protoname[strlen(protoname) - 1]))
protoname[strlen(protoname) - 1] = '\0';
sp = getservbyname(sep->se_service, protoname);
if (sp == 0) {
bb_error_msg("%s/%s: unknown service",
sep->se_service, sep->se_proto);
goto serv_unknown;
}
port = sp->s_port;
}
if (port != sep->se_ctrladdr_in.sin_port) {
sep->se_ctrladdr_in.sin_port = port;
if (sep->se_fd != -1) {
FD_CLR(sep->se_fd, &allsock);
nsock--;
(void) close(sep->se_fd);
}
sep->se_fd = -1;
}
if (sep->se_fd == -1)
setup(sep);
}
break;
#if ENABLE_FEATURE_IPV6
case AF_INET6:
sep->se_ctrladdr_in6.sin6_family = AF_INET6;
/* se_ctrladdr_in was set in getconfigent */
sep->se_ctrladdr_size = sizeof sep->se_ctrladdr_in6;
#if ENABLE_FEATURE_INETD_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) {
bb_error_msg("%s: unknown rpc service", sep->se_service);
goto serv_unknown;
}
sep->se_rpcprog = rp->r_number;
}
if (sep->se_fd == -1)
setup(sep);
if (sep->se_fd != -1)
register_rpc(sep);
} else
#endif
{
uint16_t port = htons(atoi(sep->se_service));
if (!port) {
/*XXX*/ strncpy(protoname, sep->se_proto, sizeof(protoname));
if (isdigit(protoname[strlen(protoname) - 1]))
protoname[strlen(protoname) - 1] = '\0';
sp = getservbyname(sep->se_service, protoname);
if (sp == 0) {
bb_error_msg("%s/%s: unknown service",
sep->se_service, sep->se_proto);
goto serv_unknown;
}
port = sp->s_port;
}
if (port != sep->se_ctrladdr_in6.sin6_port) {
sep->se_ctrladdr_in6.sin6_port = port;
if (sep->se_fd != -1) {
FD_CLR(sep->se_fd, &allsock);
nsock--;
(void) close(sep->se_fd);
}
sep->se_fd = -1;
}
if (sep->se_fd == -1)
setup(sep);
}
break;
#endif /* FEATURE_IPV6 */
}
serv_unknown:
if (cp->se_next != NULL) {
servtab_t *tmp = cp;
cp = cp->se_next;
free(tmp);
} else {
free(cp);
cp = getconfigent();
}
}
endconfig();
/*
* Purge anything not looked at above.
*/
Block_Using_Signals(omask);
sepp = &servtab;
while ((sep = *sepp)) {
if (sep->se_checked) {
sepp = &sep->se_next;
continue;
}
*sepp = sep->se_next;
if (sep->se_fd != -1) {
FD_CLR(sep->se_fd, &allsock);
nsock--;
(void) close(sep->se_fd);
}
#if ENABLE_FEATURE_INETD_RPC
if (isrpcservice(sep))
unregister_rpc(sep);
#endif
if (sep->se_family == AF_UNIX)
(void) unlink(sep->se_service);
freeconfig(sep);
free(sep);
}
sigprocmask(SIG_UNBLOCK, &omask, NULL);
}
static void reapchild(int sig ATTRIBUTE_UNUSED)
{
pid_t pid;
int save_errno = errno, status;
servtab_t *sep;
for (;;) {
pid = wait3(&status, WNOHANG, NULL);
if (pid <= 0)
break;
for (sep = servtab; sep; sep = sep->se_next)
if (sep->se_wait == pid) {
if (WIFEXITED(status) && WEXITSTATUS(status))
bb_error_msg("%s: exit status 0x%x",
sep->se_server, WEXITSTATUS(status));
else if (WIFSIGNALED(status))
bb_error_msg("%s: exit signal 0x%x",
sep->se_server, WTERMSIG(status));
sep->se_wait = 1;
FD_SET(sep->se_fd, &allsock);
nsock++;
}
}
errno = save_errno;
}
static void retry(int sig ATTRIBUTE_UNUSED)
{
servtab_t *sep;
timingout = 0;
for (sep = servtab; sep; sep = sep->se_next) {
if (sep->se_fd == -1) {
switch (sep->se_family) {
case AF_UNIX:
case AF_INET:
#if ENABLE_FEATURE_IPV6
case AF_INET6:
#endif
setup(sep);
#if ENABLE_FEATURE_INETD_RPC
if (sep->se_fd != -1 && isrpcservice(sep))
register_rpc(sep);
#endif
break;
}
}
}
}
static void goaway(int sig ATTRIBUTE_UNUSED)
{
servtab_t *sep;
/* XXX signal race walking sep list */
for (sep = servtab; sep; sep = sep->se_next) {
if (sep->se_fd == -1)
continue;
switch (sep->se_family) {
case AF_UNIX:
(void) unlink(sep->se_service);
break;
case AF_INET:
#if ENABLE_FEATURE_IPV6
case AF_INET6:
#endif
#if ENABLE_FEATURE_INETD_RPC
if (sep->se_wait == 1 && isrpcservice(sep))
unregister_rpc(sep); /* XXX signal race */
#endif
break;
}
(void) close(sep->se_fd);
}
remove_pidfile(_PATH_INETDPID);
exit(0);
}
#ifdef INETD_SETPROCTITLE
static void
inetd_setproctitle(char *a, int s)
{
socklen_t size;
char *cp;
struct sockaddr_in prt_sin;
char buf[80];
cp = Argv[0];
size = sizeof(prt_sin);
(void) snprintf(buf, sizeof buf, "-%s", a);
if (getpeername(s, (struct sockaddr *) &prt_sin, &size) == 0) {
char *sa = inet_ntoa(prt_sin.sin_addr);
buf[sizeof(buf) - 1 - strlen(sa) - 3] = '\0';
strcat(buf, " [");
strcat(buf, sa);
strcat(buf, "]");
}
strncpy(cp, buf, LastArg - cp);
cp += strlen(cp);
while (cp < LastArg)
*cp++ = ' ';
}
#endif
int inetd_main(int argc, char **argv);
int inetd_main(int argc, char **argv)
{
servtab_t *sep;
struct passwd *pwd;
struct group *grp = NULL;
int tmpint;
struct sigaction sa, sapipe;
int opt;
pid_t pid;
char buf[50];
char *stoomany;
sigset_t omask, wait_mask;
#ifdef INETD_SETPROCTITLE
char **envp;
#endif
INIT_G();
#ifdef INETD_SETPROCTITLE
envp = environ;
Argv = argv;
if (envp == 0 || *envp == 0)
envp = argv;
while (*envp)
envp++;
LastArg = envp[-1] + strlen(envp[-1]);
#endif
uid = getuid();
if (uid != 0)
config_filename = NULL;
opt = getopt32(argv, "R:f", &stoomany);
if (opt & 1)
toomany = xatoi_u(stoomany);
argv += optind;
argc -= optind;
if (argc)
config_filename = argv[0];
if (config_filename == NULL)
bb_error_msg_and_die("non-root must specify a config file");
if (!(opt & 2))
bb_daemonize_or_rexec(0, argv - optind);
else
bb_sanitize_stdio();
openlog(applet_name, LOG_PID | LOG_NOWAIT, LOG_DAEMON);
logmode = LOGMODE_SYSLOG;
if (uid == 0) {
/* If run by hand, ensure groups vector gets trashed */
gid_t gid = getgid();
setgroups(1, &gid);
}
write_pidfile(_PATH_INETDPID);
if (getrlimit(RLIMIT_NOFILE, &rlim_ofile) < 0) {
bb_perror_msg("getrlimit");
} else {
rlim_ofile_cur = rlim_ofile.rlim_cur;
if (rlim_ofile_cur == RLIM_INFINITY) /* ! */
rlim_ofile_cur = OPEN_MAX;
}
memset((char *) &sa, 0, sizeof(sa));
sigemptyset(&sa.sa_mask);
sigaddset(&sa.sa_mask, SIGALRM);
sigaddset(&sa.sa_mask, SIGCHLD);
sigaddset(&sa.sa_mask, SIGHUP);
sa.sa_handler = retry;
sigaction(SIGALRM, &sa, NULL);
config(SIGHUP);
sa.sa_handler = config;
sigaction(SIGHUP, &sa, NULL);
sa.sa_handler = reapchild;
sigaction(SIGCHLD, &sa, NULL);
sa.sa_handler = goaway;
sigaction(SIGTERM, &sa, NULL);
sa.sa_handler = goaway;
sigaction(SIGINT, &sa, NULL);
sa.sa_handler = SIG_IGN;
sigaction(SIGPIPE, &sa, &sapipe);
memset(&wait_mask, 0, sizeof(wait_mask));
{
/* space for daemons to overwrite environment for ps */
#define DUMMYSIZE 100
char dummy[DUMMYSIZE];
(void) memset(dummy, 'x', DUMMYSIZE - 1);
dummy[DUMMYSIZE - 1] = '\0';
(void) setenv("inetd_dummy", dummy, 1);
}
for (;;) {
int n, ctrl = -1;
fd_set readable;
if (nsock == 0) {
Block_Using_Signals(omask);
while (nsock == 0)
sigsuspend(&wait_mask);
sigprocmask(SIG_UNBLOCK, &omask, NULL);
}
readable = allsock;
n = select(maxsock + 1, &readable, NULL, NULL, NULL);
if (n <= 0) {
if (n < 0 && errno != EINTR) {
bb_perror_msg("select");
sleep(1);
}
continue;
}
for (sep = servtab; n && sep; sep = sep->se_next) {
if (sep->se_fd == -1 || !FD_ISSET(sep->se_fd, &readable))
continue;
n--;
if (!sep->se_wait && sep->se_socktype == SOCK_STREAM) {
ctrl = accept(sep->se_fd, NULL, NULL);
if (ctrl < 0) {
if (errno == EINTR)
continue;
bb_perror_msg("accept (for %s)", sep->se_service);
continue;
}
if (sep->se_family == AF_INET && sep->se_socktype == SOCK_STREAM) {
struct sockaddr_in peer;
socklen_t plen = sizeof(peer);
if (getpeername(ctrl, (struct sockaddr *) &peer, &plen) < 0) {
bb_error_msg("cannot getpeername");
close(ctrl);
continue;
}
if (ntohs(peer.sin_port) == 20) {
/* XXX ftp bounce */
close(ctrl);
continue;
}
}
} else
ctrl = sep->se_fd;
Block_Using_Signals(omask);
pid = 0;
#ifdef INETD_FEATURE_ENABLED
if (sep->se_bi == 0 || sep->se_bi->bi_fork)
#endif
{
if (sep->se_count++ == 0)
(void) gettimeofday(&sep->se_time, NULL);
else if (toomany > 0 && 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 {
if (!sep->se_wait && sep->se_socktype == SOCK_STREAM)
close(ctrl);
if (sep->se_family == AF_INET &&
ntohs(sep->se_ctrladdr_in.sin_port) >= IPPORT_RESERVED) {
/*
* Cannot close it -- there are
* thieves on the system.
* Simply ignore the connection.
*/
--sep->se_count;
continue;
}
bb_error_msg("%s/%s server failing (looping), service terminated",
sep->se_service, sep->se_proto);
if (!sep->se_wait && sep->se_socktype == SOCK_STREAM)
close(ctrl);
FD_CLR(sep->se_fd, &allsock);
(void) close(sep->se_fd);
sep->se_fd = -1;
sep->se_count = 0;
nsock--;
sigprocmask(SIG_UNBLOCK, &omask, NULL);
if (!timingout) {
timingout = 1;
alarm(RETRYTIME);
}
continue;
}
}
pid = fork();
}
if (pid < 0) {
bb_perror_msg("fork");
if (!sep->se_wait && sep->se_socktype == SOCK_STREAM)
close(ctrl);
sigprocmask(SIG_UNBLOCK, &omask, NULL);
sleep(1);
continue;
}
if (pid && sep->se_wait) {
sep->se_wait = pid;
FD_CLR(sep->se_fd, &allsock);
nsock--;
}
sigprocmask(SIG_UNBLOCK, &omask, NULL);
if (pid == 0) {
#ifdef INETD_FEATURE_ENABLED
if (sep->se_bi) {
(*sep->se_bi->bi_fn)(ctrl, sep);
} else
#endif
{
pwd = getpwnam(sep->se_user);
if (pwd == NULL) {
bb_error_msg("getpwnam: %s: no such user", sep->se_user);
goto do_exit1;
}
if (setsid() < 0)
bb_perror_msg("%s: setsid", sep->se_service);
if (sep->se_group && (grp = getgrnam(sep->se_group)) == NULL) {
bb_error_msg("getgrnam: %s: no such group", sep->se_group);
goto do_exit1;
}
if (uid != 0) {
/* a user running private inetd */
if (uid != pwd->pw_uid)
_exit(1);
} else if (pwd->pw_uid) {
if (sep->se_group)
pwd->pw_gid = grp->gr_gid;
xsetgid((gid_t) pwd->pw_gid);
initgroups(pwd->pw_name, pwd->pw_gid);
xsetuid((uid_t) pwd->pw_uid);
} else if (sep->se_group) {
xsetgid(grp->gr_gid);
setgroups(1, &grp->gr_gid);
}
dup2(ctrl, 0);
if (ctrl) close(ctrl);
dup2(0, 1);
dup2(0, 2);
if (rlim_ofile.rlim_cur != rlim_ofile_cur)
if (setrlimit(RLIMIT_NOFILE, &rlim_ofile) < 0)
bb_perror_msg("setrlimit");
closelog();
for (tmpint = rlim_ofile_cur - 1; --tmpint > 2;)
(void) close(tmpint);
sigaction(SIGPIPE, &sapipe, NULL);
execv(sep->se_server, sep->se_argv);
bb_perror_msg("execv %s", sep->se_server);
do_exit1:
if (sep->se_socktype != SOCK_STREAM)
recv(0, buf, sizeof(buf), 0);
_exit(1);
}
}
if (!sep->se_wait && sep->se_socktype == SOCK_STREAM)
close(ctrl);
} /* for (sep = servtab...) */
} /* for (;;) */
}
/*
* Internet services provided internally by inetd:
*/
#define BUFSIZE 4096
#if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_ECHO || \
ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_CHARGEN || \
ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_DAYTIME
static int dg_badinput(struct sockaddr_in *dg_sin)
{
if (ntohs(dg_sin->sin_port) < IPPORT_RESERVED)
return 1;
if (dg_sin->sin_addr.s_addr == htonl(INADDR_BROADCAST))
return 1;
/* XXX compare against broadcast addresses in SIOCGIFCONF list? */
return 0;
}
#endif
#if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_ECHO
/* Echo service -- echo data back */
/* ARGSUSED */
static void
echo_stream(int s, servtab_t *sep)
{
char buffer[BUFSIZE];
int i;
inetd_setproctitle(sep->se_service, s);
while (1) {
i = read(s, buffer, sizeof(buffer));
if (i <= 0) break;
/* FIXME: this isnt correct - safe_write()? */
if (write(s, buffer, i) <= 0) break;
}
exit(0);
}
/* Echo service -- echo data back */
/* ARGSUSED */
static void
echo_dg(int s, servtab_t *sep ATTRIBUTE_UNUSED)
{
char buffer[BUFSIZE];
int i;
socklen_t size;
/* struct sockaddr_storage ss; */
struct sockaddr sa;
size = sizeof(sa);
i = recvfrom(s, buffer, sizeof(buffer), 0, &sa, &size);
if (i < 0)
return;
if (dg_badinput((struct sockaddr_in *) &sa))
return;
(void) sendto(s, buffer, i, 0, &sa, sizeof(sa));
}
#endif /* FEATURE_INETD_SUPPORT_BUILTIN_ECHO */
#if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_DISCARD
/* Discard service -- ignore data */
/* ARGSUSED */
static void
discard_stream(int s, servtab_t *sep)
{
char buffer[BUFSIZE];
inetd_setproctitle(sep->se_service, s);
while (1) {
errno = 0;
if (read(s, buffer, sizeof(buffer)) <= 0 && errno != EINTR)
exit(0);
}
}
/* Discard service -- ignore data */
/* ARGSUSED */
static void
discard_dg(int s, servtab_t *sep ATTRIBUTE_UNUSED)
{
char buffer[BUFSIZE];
(void) read(s, buffer, sizeof(buffer));
}
#endif /* FEATURE_INETD_SUPPORT_BUILTIN_DISCARD */
#if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_CHARGEN
#define LINESIZ 72
static void
initring(void)
{
int i;
endring = ring;
for (i = 0; i <= 128; ++i)
if (isprint(i))
*endring++ = i;
}
/* Character generator */
/* ARGSUSED */
static void
chargen_stream(int s, servtab_t *sep)
{
char *rs;
int len;
char text[LINESIZ + 2];
inetd_setproctitle(sep->se_service, s);
if (!endring) {
initring();
rs = ring;
}
text[LINESIZ] = '\r';
text[LINESIZ + 1] = '\n';
rs = ring;
for (;;) {
len = endring - rs;
if (len >= 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;
}
exit(0);
}
/* Character generator */
/* ARGSUSED */
static void
chargen_dg(int s, servtab_t *sep ATTRIBUTE_UNUSED)
{
/* struct sockaddr_storage ss; */
struct sockaddr sa;
int len;
char text[LINESIZ + 2];
socklen_t size;
if (!endring) {
initring();
ringpos = ring;
}
size = sizeof(sa);
if (recvfrom(s, text, sizeof(text), 0, &sa, &size) < 0)
return;
if (dg_badinput((struct sockaddr_in *) &sa))
return;
len = endring - ringpos;
if (len >= LINESIZ)
memmove(text, ringpos, LINESIZ);
else {
memmove(text, ringpos, len);
memmove(text + len, ring, LINESIZ - len);
}
if (++ringpos == endring)
ringpos = ring;
text[LINESIZ] = '\r';
text[LINESIZ + 1] = '\n';
(void) sendto(s, text, sizeof(text), 0, &sa, sizeof(sa));
}
#endif /* FEATURE_INETD_SUPPORT_BUILTIN_CHARGEN */
#if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_TIME
/*
* 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 unsigned machtime(void)
{
struct timeval tv;
if (gettimeofday(&tv, NULL) < 0) {
fprintf(stderr, "Unable to get time of day\n");
return 0L;
}
return htonl((unsigned) tv.tv_sec + 2208988800UL);
}
/* ARGSUSED */
static void
machtime_stream(int s, servtab_t *sep ATTRIBUTE_UNUSED)
{
unsigned result;
result = machtime();
(void) write(s, (char *) &result, sizeof(result));
}
/* ARGSUSED */
static void
machtime_dg(int s, servtab_t *sep ATTRIBUTE_UNUSED)
{
unsigned result;
/* struct sockaddr_storage ss; */
struct sockaddr sa;
struct sockaddr_in *dg_sin;
socklen_t size;
size = sizeof(sa);
if (recvfrom(s, (char *) &result, sizeof(result), 0, &sa, &size) < 0)
return;
/* if (dg_badinput((struct sockaddr *)&ss)) */
dg_sin = (struct sockaddr_in *) &sa;
if (dg_sin->sin_addr.s_addr == htonl(INADDR_BROADCAST) ||
ntohs(dg_sin->sin_port) < IPPORT_RESERVED / 2)
return;
result = machtime();
(void) sendto(s, (char *) &result, sizeof(result), 0, &sa, sizeof(sa));
}
#endif /* FEATURE_INETD_SUPPORT_BUILTIN_TIME */
#if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_DAYTIME
/* Return human-readable time of day */
/* ARGSUSED */
static void daytime_stream(int s, servtab_t *sep ATTRIBUTE_UNUSED)
{
char buffer[32];
time_t t;
t = time(NULL);
// fdprintf instead?
(void) sprintf(buffer, "%.24s\r\n", ctime(&t));
(void) write(s, buffer, strlen(buffer));
}
/* Return human-readable time of day */
/* ARGSUSED */
void
daytime_dg(int s, servtab_t *sep ATTRIBUTE_UNUSED)
{
char buffer[256];
time_t t;
/* struct sockaddr_storage ss; */
struct sockaddr sa;
socklen_t size;
t = time(NULL);
size = sizeof(sa);
if (recvfrom(s, buffer, sizeof(buffer), 0, &sa, &size) < 0)
return;
if (dg_badinput((struct sockaddr_in *) &sa))
return;
(void) sprintf(buffer, "%.24s\r\n", ctime(&t));
(void) sendto(s, buffer, strlen(buffer), 0, &sa, sizeof(sa));
}
#endif /* FEATURE_INETD_SUPPORT_BUILTIN_DAYTIME */
Reference in New Issue View Git Blame Copy Permalink