diff options
Diffstat (limited to 'release/src/router/busybox/networking/inetd.c')
| -rw-r--r-- | release/src/router/busybox/networking/inetd.c | 2310 |
1 files changed, 1300 insertions, 1010 deletions
diff --git a/release/src/router/busybox/networking/inetd.c b/release/src/router/busybox/networking/inetd.c index 4c46495a..590bf23d 100644 --- a/release/src/router/busybox/networking/inetd.c +++ b/release/src/router/busybox/networking/inetd.c @@ -1,1220 +1,1534 @@ +/* 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> */ +/* IPv6 support, many bug fixes by Denys Vlasenko (c) 2008 */ /* * Copyright (c) 1983,1991 The Regents of the University of California. * All rights reserved. * - * This code is derived from software contributed to Berkeley by - * David A. Holland. - * - * Busybox port by Vladimir Oleynik (C) 2001-2003 <dzo@simtreas.ru> - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License as published by - * the Free Software Foundation; either version 2 of the License, or - * (at your option) any later version. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU - * General Public License for more details. - * - * You should have received a copy of the GNU General Public License - * along with this program; if not, write to the Free Software - * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + * 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 +/* Inetd - Internet super-server * - * This program invokes all internet services as needed. - * connection-oriented services are invoked each time a + * This program invokes configured services when a connection + * from a peer is established or a datagram arrives. + * 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 + * expected to do a getpeername to find out peer's 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''. + * on file descriptor 0. peer's address can be obtained + * using recvfrom. * * 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 + * 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 + * service_name must be in /etc/services + * socket_type stream/dgram/raw/rdm/seqpacket * protocol must be in /etc/protocols + * (usually "tcp" or "udp") * 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) - * - * RPC services unsuported + * user[.group] or user[:group] user/group to run daemon as + * server_program full path name + * server_program_arguments maximum of MAXARGS (20) * - * Comment lines are indicated by a `#' in column 1. - */ - -/* - * Here's the scoop concerning the user.group feature: + * For RPC services + * service_name/version must be in /etc/rpc + * socket_type stream/dgram/raw/rdm/seqpacket + * rpc/protocol "rpc/tcp" etc + * 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) * - * 1) No group listed. + * 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) for root: NO setuid() or setgid() is done + * 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. * - * b) nonroot: setuid() - * setgid(primary group as found in passwd) - * initgroups(name, primary group) + * The hostaddress specifier may (and often will) contain dots; + * the service name must not. * - * 2) set-group-option on. + * 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. * - * a) for root: NO setuid() - * setgid(specified group) - * setgroups(1, specified group) + * 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): * - * b) nonroot: setuid() - * setgid(specified group) - * initgroups(name, specified group) + * 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. * - * All supplementary groups are discarded at startup in case inetd was - * run manually. + * 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. */ -#define __USE_BSD_SIGNAL +/* Despite of above doc saying that dgram services must use "wait", + * "udp nowait" servers are implemented in busyboxed inetd. + * IPv6 addresses are also implemented. However, they may look ugly - + * ":::service..." means "address '::' (IPv6 wildcard addr)":"service"... + * You have to put "tcp6"/"udp6" in protocol field to select IPv6. + */ -#include "busybox.h" +/* Here's the scoop concerning the user[:group] feature: + * 1) group is not specified: + * a) user = root: NO setuid() or setgid() is done + * b) other: initgroups(name, primary group) + * setgid(primary group as found in passwd) + * setuid() + * 2) group is specified: + * a) user = root: setgid(specified group) + * NO initgroups() + * NO setuid() + * b) other: initgroups(name, specified group) + * setgid(specified group) + * setuid() + */ -#include <sys/param.h> -#include <sys/stat.h> -#include <sys/ioctl.h> -#include <sys/socket.h> +#include <syslog.h> #include <sys/un.h> -#include <sys/file.h> -#include <sys/wait.h> -#include <sys/time.h> -#include <sys/resource.h> -#ifndef __linux__ -#ifndef RLIMIT_NOFILE -#define RLIMIT_NOFILE RLIMIT_OFILE +#include "libbb.h" + +#if ENABLE_FEATURE_INETD_RPC +#include <rpc/rpc.h> +#include <rpc/pmap_clnt.h> #endif + +#if !BB_MMU +/* stream version of chargen is forking but not execing, + * can't do that (easily) on NOMMU */ +#undef ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_CHARGEN +#define ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_CHARGEN 0 #endif -#include <sys/param.h> -#include <sys/stat.h> -#include <sys/ioctl.h> -#include <sys/socket.h> -#include <sys/file.h> -#include <sys/wait.h> -#include <sys/time.h> -#include <sys/resource.h> - -#include <netinet/in.h> -#include <netinet/ip.h> -#include <arpa/inet.h> - -#include <errno.h> -#include <signal.h> -#include <netdb.h> -#include <syslog.h> -#include <stdio.h> -#include <stdlib.h> -#include <string.h> -#include <getopt.h> -#include <unistd.h> -#include <stdarg.h> -#include <time.h> - -#define _PATH_INETDCONF "/etc/inetd.conf" #define _PATH_INETDPID "/var/run/inetd.pid" -#ifndef MIN -#define MIN(a, b) ((a) < (b) ? (a) : (b)) -#endif +#define CNT_INTERVAL 60 /* servers in CNT_INTERVAL sec. */ +#define RETRYTIME 60 /* retry after bind or server fail */ + +// TODO: explain, or get rid of setrlimit games -#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 */ +#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) -static int rlim_ofile_cur = OPEN_MAX; - -#ifdef RLIMIT_NOFILE -static struct rlimit rlim_ofile; +#define FD_MARGIN 8 + +#if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_DISCARD \ + || ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_ECHO \ + || ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_CHARGEN \ + || ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_TIME \ + || ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_DAYTIME +# define INETD_BUILTINS_ENABLED #endif -#define INETD_UNSUPPORT_BILTIN 1 - -/* Check unsupporting builtin */ -#ifdef CONFIG_FEATURE_INETD_SUPPORT_BILTIN_ECHO -#undef INETD_UNSUPPORT_BILTIN -#endif -#ifdef CONFIG_FEATURE_INETD_SUPPORT_BILTIN_DISCARD -#undef INETD_UNSUPPORT_BILTIN -#endif -#ifdef CONFIG_FEATURE_INETD_SUPPORT_BILTIN_TIME -#undef INETD_UNSUPPORT_BILTIN -#endif -#ifdef CONFIG_FEATURE_INETD_SUPPORT_BILTIN_DAYTIME -#undef INETD_UNSUPPORT_BILTIN -#endif -#ifdef CONFIG_FEATURE_INETD_SUPPORT_BILTIN_CHARGEN -#undef INETD_UNSUPPORT_BILTIN +typedef struct servtab_t { + /* The most frequently referenced one: */ + int se_fd; /* open descriptor */ + /* NB: 'biggest fields last' saves on code size (~250 bytes) */ + /* [addr:]service socktype proto wait user[:group] prog [args] */ + char *se_local_hostname; /* addr to listen on */ + char *se_service; /* "80" or "www" or "mount/2[-3]" */ + /* socktype is in se_socktype */ /* "stream" "dgram" "raw" "rdm" "seqpacket" */ + char *se_proto; /* "unix" or "[rpc/]tcp[6]" */ +#if ENABLE_FEATURE_INETD_RPC + int se_rpcprog; /* rpc program number */ + int se_rpcver_lo; /* rpc program lowest version */ + int se_rpcver_hi; /* rpc program highest version */ +#define is_rpc_service(sep) ((sep)->se_rpcver_lo != 0) +#else +#define is_rpc_service(sep) 0 #endif - -static struct servtab { - char *se_service; /* name of service */ - int se_socktype; /* type of socket to use */ - int se_family; /* address family */ - char *se_proto; /* protocol used */ - short 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 */ -#ifndef INETD_UNSUPPORT_BILTIN - const struct biltin *se_bi; /* if built-in, description */ + pid_t se_wait; /* 0:"nowait", 1:"wait", >1:"wait" */ + /* and waiting for this pid */ + socktype_t se_socktype; /* SOCK_STREAM/DGRAM/RDM/... */ + family_t se_family; /* AF_UNIX/INET[6] */ + /* se_proto_no is used by RPC code only... hmm */ + smallint se_proto_no; /* IPPROTO_TCP/UDP, n/a for AF_UNIX */ + smallint se_checked; /* looked at during merge */ + unsigned se_max; /* allowed instances per minute */ + unsigned se_count; /* number started since se_time */ + unsigned se_time; /* when we started counting */ + char *se_user; /* user name to run as */ + char *se_group; /* group name to run as, can be NULL */ +#ifdef INETD_BUILTINS_ENABLED + const struct builtin *se_builtin; /* if built-in, description */ #endif - char *se_server; /* server program */ + struct servtab_t *se_next; + len_and_sockaddr *se_lsa; + char *se_program; /* server program */ #define MAXARGV 20 - char *se_argv[MAXARGV+1]; /* program arguments */ - int se_fd; /* open descriptor */ - union { - struct sockaddr se_un_ctrladdr; - struct sockaddr_in se_un_ctrladdr_in; - 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 */ - struct servtab *se_next; -} *servtab; - -/* Length of socket listen queue. Should be per-service probably. */ -static int global_queuelen = 128; - -static int nsock, maxsock; -static fd_set allsock; -static int timingout; -static sigset_t blockmask, emptymask; - - - /* Echo received data */ -#ifdef CONFIG_FEATURE_INETD_SUPPORT_BILTIN_ECHO -static void echo_stream(int, struct servtab *); -static void echo_dg(int, struct servtab *); + char *se_argv[MAXARGV + 1]; /* program arguments */ +} servtab_t; + +#ifdef INETD_BUILTINS_ENABLED +/* 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 */ -#ifdef CONFIG_FEATURE_INETD_SUPPORT_BILTIN_DISCARD -static void discard_stream(int, struct servtab *); -static void discard_dg(int, struct servtab *); +/* 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 */ -#ifdef CONFIG_FEATURE_INETD_SUPPORT_BILTIN_TIME -static void machtime_stream(int, struct servtab *); -static void machtime_dg(int, struct servtab *); +/* 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 */ -#ifdef CONFIG_FEATURE_INETD_SUPPORT_BILTIN_DAYTIME -static void daytime_stream(int, struct servtab *); -static void daytime_dg(int, struct servtab *); +/* 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 */ -#ifdef CONFIG_FEATURE_INETD_SUPPORT_BILTIN_CHARGEN -static void chargen_stream(int, struct servtab *); -static void chargen_dg(int, struct servtab *); +/* 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 -#ifndef INETD_UNSUPPORT_BILTIN -struct biltin { - const 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 *); /* fn which performs it */ +struct builtin { + /* NB: not necessarily NUL terminated */ + char bi_service7[7]; /* internally provided service name */ + uint8_t bi_fork; /* 1 if stream fn should run in child */ + void (*bi_stream_fn)(int, servtab_t *); + void (*bi_dgram_fn)(int, servtab_t *); }; -static const struct biltin biltins[] = { -#ifdef CONFIG_FEATURE_INETD_SUPPORT_BILTIN_ECHO - /* Echo received data */ - { "echo", SOCK_STREAM, 1, 0, echo_stream, }, - { "echo", SOCK_DGRAM, 0, 0, echo_dg, }, +static const struct builtin builtins[] = { +#if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_ECHO + { "echo", 1, echo_stream, echo_dg }, #endif -#ifdef CONFIG_FEATURE_INETD_SUPPORT_BILTIN_DISCARD - /* Internet /dev/null */ - { "discard", SOCK_STREAM, 1, 0, discard_stream, }, - { "discard", SOCK_DGRAM, 0, 0, discard_dg, }, +#if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_DISCARD + { "discard", 1, discard_stream, discard_dg }, #endif -#ifdef CONFIG_FEATURE_INETD_SUPPORT_BILTIN_TIME - /* Return 32 bit time since 1900 */ - { "time", SOCK_STREAM, 0, 0, machtime_stream, }, - { "time", SOCK_DGRAM, 0, 0, machtime_dg, }, +#if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_CHARGEN + { "chargen", 1, chargen_stream, chargen_dg }, #endif -#ifdef CONFIG_FEATURE_INETD_SUPPORT_BILTIN_DAYTIME - /* Return human-readable time */ - { "daytime", SOCK_STREAM, 0, 0, daytime_stream, }, - { "daytime", SOCK_DGRAM, 0, 0, daytime_dg, }, +#if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_TIME + { "time", 0, machtime_stream, machtime_dg }, #endif -#ifdef CONFIG_FEATURE_INETD_SUPPORT_BILTIN_CHARGEN - /* Familiar character generator */ - { "chargen", SOCK_STREAM, 1, 0, chargen_stream, }, - { "chargen", SOCK_DGRAM, 0, 0, chargen_dg, }, +#if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_DAYTIME + { "daytime", 0, daytime_stream, daytime_dg }, #endif - { NULL, 0, 0, 0, NULL } }; -#endif /* INETD_UNSUPPORT_BILTIN */ - -#define NUMINT (sizeof(intab) / sizeof(struct inent)) -static const char *CONFIG = _PATH_INETDCONF; +#endif /* INETD_BUILTINS_ENABLED */ + +struct globals { + rlim_t rlim_ofile_cur; + struct rlimit rlim_ofile; + servtab_t *serv_list; + int global_queuelen; + int maxsock; /* max fd# in allsock, -1: unknown */ + /* whenever maxsock grows, prev_maxsock is set to new maxsock, + * but if maxsock is set to -1, prev_maxsock is not changed */ + int prev_maxsock; + unsigned max_concurrency; + smallint alarm_armed; + uid_t real_uid; /* user ID who ran us */ + const char *config_filename; + parser_t *parser; + char *default_local_hostname; +#if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_CHARGEN + char *end_ring; + char *ring_pos; + char ring[128]; +#endif + fd_set allsock; + /* Used in next_line(), and as scratch read buffer */ + char line[256]; /* _at least_ 256, 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 serv_list (G.serv_list ) +#define global_queuelen (G.global_queuelen) +#define maxsock (G.maxsock ) +#define prev_maxsock (G.prev_maxsock ) +#define max_concurrency (G.max_concurrency) +#define alarm_armed (G.alarm_armed ) +#define real_uid (G.real_uid ) +#define config_filename (G.config_filename) +#define parser (G.parser ) +#define default_local_hostname (G.default_local_hostname) +#define first_ps_byte (G.first_ps_byte ) +#define last_ps_byte (G.last_ps_byte ) +#define end_ring (G.end_ring ) +#define ring_pos (G.ring_pos ) +#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) + +static void maybe_close(int fd) +{ + if (fd >= 0) + close(fd); +} -#define BCOPY(s, d, z) memcpy(d, s, z) +// TODO: move to libbb? +static len_and_sockaddr *xzalloc_lsa(int family) +{ + len_and_sockaddr *lsa; + int sz; + + sz = sizeof(struct sockaddr_in); + if (family == AF_UNIX) + sz = sizeof(struct sockaddr_un); +#if ENABLE_FEATURE_IPV6 + if (family == AF_INET6) + sz = sizeof(struct sockaddr_in6); +#endif + lsa = xzalloc(LSA_LEN_SIZE + sz); + lsa->len = sz; + lsa->u.sa.sa_family = family; + return lsa; +} -static void -syslog_err_and_discard_dg(int se_socktype, const char *msg, ...) - __attribute__ ((noreturn, format (printf, 2, 3))); +static void rearm_alarm(void) +{ + if (!alarm_armed) { + alarm_armed = 1; + alarm(RETRYTIME); + } +} -static void -syslog_err_and_discard_dg(int se_socktype, const char *msg, ...) +static void block_CHLD_HUP_ALRM(sigset_t *m) { - char buf[50]; - va_list p; - - va_start(p, msg); - vsyslog(LOG_ERR, msg, p); - if (se_socktype != SOCK_STREAM) - recv(0, buf, sizeof (buf), 0); - _exit(1); + sigemptyset(m); + sigaddset(m, SIGCHLD); + sigaddset(m, SIGHUP); + sigaddset(m, SIGALRM); + sigprocmask(SIG_BLOCK, m, m); /* old sigmask is stored in m */ } -static FILE *fconfig; -static char line[256]; +static void restore_sigmask(sigset_t *m) +{ + sigprocmask(SIG_SETMASK, m, NULL); +} -static FILE * -setconfig(void) +#if ENABLE_FEATURE_INETD_RPC +static void register_rpc(servtab_t *sep) { - FILE *f = fconfig; + int n; + struct sockaddr_in ir_sin; + socklen_t size; - if (f != NULL) { - fseek(f, 0L, L_SET); - } else { - f = fconfig = fopen(CONFIG, "r"); - if(f == NULL) - syslog(LOG_ERR, "%s: %m", CONFIG); + size = sizeof(ir_sin); + if (getsockname(sep->se_fd, (struct sockaddr *) &ir_sin, &size) < 0) { + bb_perror_msg("getsockname"); + return; } - return f; -} -static char * -nextline(void) -{ - char *cp; - FILE *fd = fconfig; - - if (fgets(line, sizeof (line), fd) == NULL) - return ((char *)0); - cp = strchr(line, '\n'); - if (cp) - *cp = '\0'; - return (line); + for (n = sep->se_rpcver_lo; n <= sep->se_rpcver_hi; n++) { + pmap_unset(sep->se_rpcprog, n); + if (!pmap_set(sep->se_rpcprog, n, sep->se_proto_no, 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, sep->se_proto_no, ntohs(ir_sin.sin_port)); + } } -static char * -skip(char **cpp) +static void unregister_rpc(servtab_t *sep) { - char *cp = *cpp; - char *start; - - if (*cpp == NULL) - return ((char *)0); - -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()) != NULL) - goto again; - *cpp = NULL; - return NULL; + int n; + + for (n = sep->se_rpcver_lo; n <= sep->se_rpcver_hi; n++) { + if (!pmap_unset(sep->se_rpcprog, n)) + bb_perror_msg("pmap_unset(%u,%u)", sep->se_rpcprog, n); } - start = cp; - while (*cp && *cp != ' ' && *cp != '\t') - cp++; - if (*cp != '\0') - *cp++ = '\0'; - *cpp = cp; - return (start); } +#endif /* FEATURE_INETD_RPC */ -static char * -newstr(char *cp) +static void bump_nofile(void) { - cp = strdup(cp ? cp : ""); - if (cp) - return(cp); + enum { FD_CHUNK = 32 }; + struct rlimit rl; - syslog_err_and_discard_dg(SOCK_STREAM, "strdup: %m"); -} + /* Never fails under Linux (except if you pass it bad arguments) */ + getrlimit(RLIMIT_NOFILE, &rl); + 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("can't extend file limit, max = %d", + (int) rl.rlim_cur); + return; + } + if (setrlimit(RLIMIT_NOFILE, &rl) < 0) { + bb_perror_msg("setrlimit"); + return; + } -static struct servtab * -getconfigent(void) + rlim_ofile_cur = rl.rlim_cur; +} + +static void remove_fd_from_set(int fd) { - static struct servtab serv; - struct servtab *sep = &serv; - int argc; - char *cp, *arg; - -more: - while ((cp = nextline()) && *cp == '#') - ; - if (cp == NULL) - return ((struct servtab *)0); - memset((char *)sep, 0, sizeof *sep); - sep->se_service = newstr(skip(&cp)); - arg = skip(&cp); - if (arg == NULL) - goto more; - - 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; + if (fd >= 0) { + FD_CLR(fd, &allsock); + maxsock = -1; + } +} - sep->se_proto = newstr(skip(&cp)); - if (strcmp(sep->se_proto, "unix") == 0) { - sep->se_family = AF_UNIX; - } else { - sep->se_family = AF_INET; - if (strncmp(sep->se_proto, "rpc/", 4) == 0) { - syslog(LOG_ERR, "%s: rpc services not suported", - sep->se_service); - goto more; +static void add_fd_to_set(int fd) +{ + if (fd >= 0) { + FD_SET(fd, &allsock); + if (maxsock >= 0 && fd > maxsock) { + prev_maxsock = maxsock = fd; + if ((rlim_t)fd > rlim_ofile_cur - FD_MARGIN) + bump_nofile(); } } - arg = skip(&cp); - if (arg == NULL) - goto more; - { - char *s = strchr(arg, '.'); - if (s) { - *s++ = '\0'; - sep->se_max = atoi(s); - } else - sep->se_max = TOOMANY; +} + +static void recalculate_maxsock(void) +{ + int fd = 0; + + /* We may have no services, in this case maxsock should still be >= 0 + * (code elsewhere is not happy with maxsock == -1) */ + maxsock = 0; + while (fd <= prev_maxsock) { + if (FD_ISSET(fd, &allsock)) + maxsock = fd; + fd++; } - sep->se_wait = strcmp(arg, "wait") == 0; - sep->se_user = newstr(skip(&cp)); - sep->se_group = strchr(sep->se_user, '.'); - if (sep->se_group) { - *sep->se_group++ = '\0'; + prev_maxsock = maxsock; + if ((rlim_t)maxsock > rlim_ofile_cur - FD_MARGIN) + bump_nofile(); +} + +static void prepare_socket_fd(servtab_t *sep) +{ + int r, fd; + + fd = socket(sep->se_family, sep->se_socktype, 0); + if (fd < 0) { + bb_perror_msg("socket"); + return; } - sep->se_server = newstr(skip(&cp)); - if (strcmp(sep->se_server, "internal") == 0) { -#ifndef INETD_UNSUPPORT_BILTIN - const 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; + setsockopt_reuseaddr(fd); + +#if ENABLE_FEATURE_INETD_RPC + if (is_rpc_service(sep)) { + struct passwd *pwd; + + /* zero out the port for all RPC services; let bind() + * find one. */ + set_nport(sep->se_lsa, 0); + + /* for RPC services, attempt to use a reserved port + * if they are going to be running as root. */ + if (real_uid == 0 && sep->se_family == AF_INET + && (pwd = getpwnam(sep->se_user)) != NULL + && pwd->pw_uid == 0 + ) { + r = bindresvport(fd, &sep->se_lsa->u.sin); + } else { + r = bind(fd, &sep->se_lsa->u.sa, sep->se_lsa->len); + } + if (r == 0) { + int saveerrno = errno; + /* update lsa with port# */ + getsockname(fd, &sep->se_lsa->u.sa, &sep->se_lsa->len); + errno = saveerrno; } - sep->se_bi = bi; - sep->se_wait = bi->bi_wait; -#else - syslog(LOG_ERR, "internal service %s unknown", - sep->se_service); - goto more; -#endif } else -#ifndef INETD_UNSUPPORT_BILTIN - sep->se_bi = NULL #endif - ; - argc = 0; - for (arg = skip(&cp); cp; arg = skip(&cp)) { - if (argc < MAXARGV) - sep->se_argv[argc++] = newstr(arg); + { + if (sep->se_family == AF_UNIX) { + struct sockaddr_un *sun; + sun = (struct sockaddr_un*)&(sep->se_lsa->u.sa); + unlink(sun->sun_path); + } + r = bind(fd, &sep->se_lsa->u.sa, sep->se_lsa->len); } - while (argc <= MAXARGV) - sep->se_argv[argc++] = NULL; - return (sep); + if (r < 0) { + bb_perror_msg("%s/%s: bind", + sep->se_service, sep->se_proto); + close(fd); + rearm_alarm(); + return; + } + if (sep->se_socktype == SOCK_STREAM) + listen(fd, global_queuelen); + + add_fd_to_set(fd); + sep->se_fd = fd; } -static void -freeconfig(struct servtab *cp) +static int reopen_config_file(void) +{ + free(default_local_hostname); + default_local_hostname = xstrdup("*"); + if (parser != NULL) + config_close(parser); + parser = config_open(config_filename); + return (parser != NULL); +} + +static void close_config_file(void) +{ + if (parser) { + config_close(parser); + parser = NULL; + } +} + +static void free_servtab_strings(servtab_t *cp) { int i; + free(cp->se_local_hostname); free(cp->se_service); free(cp->se_proto); free(cp->se_user); - /* Note: se_group is part of the newstr'ed se_user */ - free(cp->se_server); + free(cp->se_group); + free(cp->se_lsa); /* not a string in fact */ + free(cp->se_program); for (i = 0; i < MAXARGV; i++) free(cp->se_argv[i]); } -#ifndef INETD_UNSUPPORT_BILTIN -static char **Argv; -static char *LastArg; - -static void -setproctitle(char *a, int s) +static servtab_t *new_servtab(void) { - size_t size; - char *cp; - struct sockaddr_in sn; - char buf[80]; - - cp = Argv[0]; - size = sizeof(sn); - if (getpeername(s, (struct sockaddr *)&sn, &size) == 0) - (void) sprintf(buf, "-%s [%s]", a, inet_ntoa(sn.sin_addr)); - else - (void) sprintf(buf, "-%s", a); - strncpy(cp, buf, LastArg - cp); - cp += strlen(cp); - while (cp < LastArg) - *cp++ = ' '; + servtab_t *newtab = xzalloc(sizeof(servtab_t)); + newtab->se_fd = -1; /* paranoia */ + return newtab; } -#endif /* INETD_UNSUPPORT_BILTIN */ -static struct servtab * -enter(struct servtab *cp) +static servtab_t *dup_servtab(servtab_t *sep) { - struct servtab *sep; - sigset_t oldmask; + servtab_t *newtab; + int argc; - sep = (struct servtab *)malloc(sizeof (*sep)); - if (sep == NULL) { - syslog_err_and_discard_dg(SOCK_STREAM, bb_msg_memory_exhausted); - } - *sep = *cp; - sep->se_fd = -1; - sigprocmask(SIG_BLOCK, &blockmask, &oldmask); - sep->se_next = servtab; - servtab = sep; - sigprocmask(SIG_SETMASK, &oldmask, NULL); - return (sep); + newtab = new_servtab(); + *newtab = *sep; /* struct copy */ + /* deep-copying strings */ + newtab->se_service = xstrdup(newtab->se_service); + newtab->se_proto = xstrdup(newtab->se_proto); + newtab->se_user = xstrdup(newtab->se_user); + newtab->se_group = xstrdup(newtab->se_group); + newtab->se_program = xstrdup(newtab->se_program); + for (argc = 0; argc <= MAXARGV; argc++) + newtab->se_argv[argc] = xstrdup(newtab->se_argv[argc]); + /* NB: se_fd, se_hostaddr and se_next are always + * overwrittend by callers, so we don't bother resetting them + * to NULL/0/-1 etc */ + + return newtab; } -static int -bump_nofile(void) +/* gcc generates much more code if this is inlined */ +static servtab_t *parse_one_line(void) { -#ifdef RLIMIT_NOFILE - -#define FD_CHUNK 32 + int argc; + char *token[6+MAXARGV]; + char *p, *arg; + char *hostdelim; + servtab_t *sep; + servtab_t *nsep; + new: + sep = new_servtab(); + more: + argc = config_read(parser, token, 6+MAXARGV, 1, "# \t", PARSE_NORMAL); + if (!argc) { + free(sep); + return NULL; + } - struct rlimit rl; + /* [host:]service socktype proto wait user[:group] prog [args] */ + /* Check for "host:...." line */ + arg = token[0]; + hostdelim = strrchr(arg, ':'); + if (hostdelim) { + *hostdelim = '\0'; + sep->se_local_hostname = xstrdup(arg); + arg = hostdelim + 1; + if (*arg == '\0' && argc == 1) { + /* Line has just "host:", change the + * default host for the following lines. */ + free(default_local_hostname); + default_local_hostname = sep->se_local_hostname; + goto more; + } + } else + sep->se_local_hostname = xstrdup(default_local_hostname); + + /* service socktype proto wait user[:group] prog [args] */ + sep->se_service = xstrdup(arg); + + /* socktype proto wait user[:group] prog [args] */ + if (argc < 6) { + parse_err: + bb_error_msg("parse error on line %u, line is ignored", + parser->lineno); + free_servtab_strings(sep); + /* Just "goto more" can make sep to carry over e.g. + * "rpc"-ness (by having se_rpcver_lo != 0). + * We will be more paranoid: */ + free(sep); + goto new; + } - if (getrlimit(RLIMIT_NOFILE, &rl) < 0) { - syslog(LOG_ERR, "getrlimit: %m"); - return -1; + { + static int8_t SOCK_xxx[] ALIGN1 = { + -1, + SOCK_STREAM, SOCK_DGRAM, SOCK_RDM, + SOCK_SEQPACKET, SOCK_RAW + }; + sep->se_socktype = SOCK_xxx[1 + index_in_strings( + "stream""\0" "dgram""\0" "rdm""\0" + "seqpacket""\0" "raw""\0" + , token[1])]; } - rl.rlim_cur = MIN(rl.rlim_max, rl.rlim_cur + FD_CHUNK); - if (rl.rlim_cur <= rlim_ofile_cur) { - syslog(LOG_ERR, -#if _FILE_OFFSET_BITS == 64 - "bump_nofile: cannot extend file limit, max = %lld", + + /* {unix,[rpc/]{tcp,udp}[6]} wait user[:group] prog [args] */ + sep->se_proto = arg = xstrdup(token[2]); + if (strcmp(arg, "unix") == 0) { + sep->se_family = AF_UNIX; + } else { + char *six; + sep->se_family = AF_INET; + six = last_char_is(arg, '6'); + if (six) { +#if ENABLE_FEATURE_IPV6 + *six = '\0'; + sep->se_family = AF_INET6; +#else + bb_error_msg("%s: no support for IPv6", sep->se_proto); + goto parse_err; +#endif + } + if (strncmp(arg, "rpc/", 4) == 0) { +#if ENABLE_FEATURE_INETD_RPC + unsigned n; + arg += 4; + p = strchr(sep->se_service, '/'); + if (p == NULL) { + bb_error_msg("no rpc version: '%s'", sep->se_service); + goto parse_err; + } + *p++ = '\0'; + n = bb_strtou(p, &p, 10); + if (n > INT_MAX) { + bad_ver_spec: + bb_error_msg("bad rpc version"); + goto parse_err; + } + sep->se_rpcver_lo = sep->se_rpcver_hi = n; + if (*p == '-') { + p++; + n = bb_strtou(p, &p, 10); + if (n > INT_MAX || (int)n < sep->se_rpcver_lo) + goto bad_ver_spec; + sep->se_rpcver_hi = n; + } + if (*p != '\0') + goto bad_ver_spec; #else - "bump_nofile: cannot extend file limit, max = %ld", + bb_error_msg("no support for rpc services"); + goto parse_err; #endif - rl.rlim_cur); - return -1; + } + /* we don't really need getprotobyname()! */ + if (strcmp(arg, "tcp") == 0) + sep->se_proto_no = IPPROTO_TCP; /* = 6 */ + if (strcmp(arg, "udp") == 0) + sep->se_proto_no = IPPROTO_UDP; /* = 17 */ + if (six) + *six = '6'; + if (!sep->se_proto_no) /* not tcp/udp?? */ + goto parse_err; } - if (setrlimit(RLIMIT_NOFILE, &rl) < 0) { - syslog(LOG_ERR, "setrlimit: %m"); - return -1; + /* [no]wait[.max] user[:group] prog [args] */ + arg = token[3]; + sep->se_max = max_concurrency; + p = strchr(arg, '.'); + if (p) { + *p++ = '\0'; + sep->se_max = bb_strtou(p, NULL, 10); + if (errno) + goto parse_err; + } + sep->se_wait = (arg[0] != 'n' || arg[1] != 'o'); + if (!sep->se_wait) /* "no" seen */ + arg += 2; + if (strcmp(arg, "wait") != 0) + goto parse_err; + + /* user[:group] prog [args] */ + sep->se_user = xstrdup(token[4]); + arg = strchr(sep->se_user, '.'); + if (arg == NULL) + arg = strchr(sep->se_user, ':'); + if (arg) { + *arg++ = '\0'; + sep->se_group = xstrdup(arg); } - rlim_ofile_cur = rl.rlim_cur; - return 0; - -#else - syslog(LOG_ERR, "bump_nofile: cannot extend file limit"); - return -1; + /* prog [args] */ + sep->se_program = xstrdup(token[5]); +#ifdef INETD_BUILTINS_ENABLED + if (strcmp(sep->se_program, "internal") == 0 + && strlen(sep->se_service) <= 7 + && (sep->se_socktype == SOCK_STREAM + || sep->se_socktype == SOCK_DGRAM) + ) { + unsigned i; + for (i = 0; i < ARRAY_SIZE(builtins); i++) + if (strncmp(builtins[i].bi_service7, sep->se_service, 7) == 0) + goto found_bi; + bb_error_msg("unknown internal service %s", sep->se_service); + goto parse_err; + found_bi: + sep->se_builtin = &builtins[i]; + /* stream builtins must be "nowait", dgram must be "wait" */ + if (sep->se_wait != (sep->se_socktype == SOCK_DGRAM)) + goto parse_err; + } #endif -} - - -static void -setup(struct servtab *sep) -{ - int on = 1; + argc = 0; + while ((arg = token[6+argc]) != NULL && argc < MAXARGV) + sep->se_argv[argc++] = xstrdup(arg); - if ((sep->se_fd = socket(sep->se_family, sep->se_socktype, 0)) < 0) { - syslog(LOG_ERR, "%s/%s: socket: %m", - sep->se_service, sep->se_proto); - return; + /* catch mixups. "<service> stream udp ..." == wtf */ + if (sep->se_socktype == SOCK_STREAM) { + if (sep->se_proto_no == IPPROTO_UDP) + goto parse_err; } - if (setsockopt(sep->se_fd, SOL_SOCKET, SO_REUSEADDR, (void *)&on, - sizeof(on)) < 0) - syslog(LOG_ERR, "setsockopt (SO_REUSEADDR): %m"); - if (bind(sep->se_fd, &sep->se_ctrladdr, sep->se_ctrladdr_size) < 0) { - 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_DGRAM) { + if (sep->se_proto_no == IPPROTO_TCP) + goto parse_err; } - 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 (maxsock > rlim_ofile_cur - FD_MARGIN) - bump_nofile(); + +// bb_info_msg( +// "ENTRY[%s][%s][%s][%d][%d][%d][%d][%d][%s][%s][%s]", +// sep->se_local_hostname, sep->se_service, sep->se_proto, sep->se_wait, sep->se_proto_no, +// sep->se_max, sep->se_count, sep->se_time, sep->se_user, sep->se_group, sep->se_program); + + /* check if the hostname specifier is a comma separated list + * of hostnames. we'll make new entries for each address. */ + while ((hostdelim = strrchr(sep->se_local_hostname, ',')) != NULL) { + nsep = dup_servtab(sep); + /* NUL terminate the hostname field of the existing entry, + * and make a dup for the new entry. */ + *hostdelim++ = '\0'; + nsep->se_local_hostname = xstrdup(hostdelim); + nsep->se_next = sep->se_next; + sep->se_next = nsep; } + + /* was doing it here: */ + /* DNS resolution, create copies for each IP address */ + /* IPv6-ization destroyed it :( */ + + return sep; } -static void -config(int signum) +static servtab_t *insert_in_servlist(servtab_t *cp) { - struct servtab *sep, *cp, **sepp; - sigset_t oldmask; - unsigned n; + servtab_t *sep; + sigset_t omask; - (void)signum; - if (setconfig() == NULL) - return; + sep = new_servtab(); + *sep = *cp; /* struct copy */ + sep->se_fd = -1; +#if ENABLE_FEATURE_INETD_RPC + sep->se_rpcprog = -1; +#endif + block_CHLD_HUP_ALRM(&omask); + sep->se_next = serv_list; + serv_list = sep; + restore_sigmask(&omask); + return sep; +} + +static int same_serv_addr_proto(servtab_t *old, servtab_t *new) +{ + if (strcmp(old->se_local_hostname, new->se_local_hostname) != 0) + return 0; + if (strcmp(old->se_service, new->se_service) != 0) + return 0; + if (strcmp(old->se_proto, new->se_proto) != 0) + return 0; + return 1; +} + +static void reread_config_file(int sig UNUSED_PARAM) +{ + servtab_t *sep, *cp, **sepp; + len_and_sockaddr *lsa; + sigset_t omask; + unsigned n; + uint16_t port; + int save_errno = errno; - for (sep = servtab; sep; sep = sep->se_next) + if (!reopen_config_file()) + goto ret; + for (sep = serv_list; sep; sep = sep->se_next) sep->se_checked = 0; - while ((cp = getconfigent()) != NULL) { - for (sep = servtab; sep; sep = sep->se_next) - if (strcmp(sep->se_service, cp->se_service) == 0 && - strcmp(sep->se_proto, cp->se_proto) == 0) + + goto first_line; + while (1) { + if (cp == NULL) { + first_line: + cp = parse_one_line(); + if (cp == NULL) break; - if (sep != 0) { + } + for (sep = serv_list; sep; sep = sep->se_next) + if (same_serv_addr_proto(sep, cp)) + goto equal_servtab; + /* not an "equal" servtab */ + sep = insert_in_servlist(cp); + goto after_check; + equal_servtab: + { int i; -#define SWAP(type, a, b) {type c=(type)a; (type)a=(type)b; (type)b=(type)c;} - - sigprocmask(SIG_BLOCK, &emptymask, &oldmask); - /* - * 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 ( -#ifndef INETD_UNSUPPORT_BILTIN - cp->se_bi == 0 && + block_CHLD_HUP_ALRM(&omask); +#if ENABLE_FEATURE_INETD_RPC + if (is_rpc_service(sep)) + unregister_rpc(sep); + sep->se_rpcver_lo = cp->se_rpcver_lo; + sep->se_rpcver_hi = cp->se_rpcver_hi; #endif - (sep->se_wait == 1 || cp->se_wait == 0)) - sep->se_wait = cp->se_wait; - if (cp->se_max != sep->se_max) - SWAP(int, cp->se_max, sep->se_max); - if (cp->se_user) - SWAP(char *, sep->se_user, cp->se_user); - if (cp->se_group) - SWAP(char *, sep->se_group, cp->se_group); - if (cp->se_server) - SWAP(char *, sep->se_server, cp->se_server); + if (cp->se_wait == 0) { + /* New config says "nowait". If old one + * was "wait", we currently may be waiting + * for a child (and not accepting connects). + * Stop waiting, start listening again. + * (if it's not true, this op is harmless) */ + add_fd_to_set(sep->se_fd); + } + sep->se_wait = cp->se_wait; + sep->se_max = cp->se_max; + /* string fields need more love - we don't want to leak them */ +#define SWAP(type, a, b) do { type c = (type)a; a = (type)b; b = (type)c; } while (0) + SWAP(char*, sep->se_user, cp->se_user); + SWAP(char*, sep->se_group, cp->se_group); + SWAP(char*, sep->se_program, cp->se_program); for (i = 0; i < MAXARGV; i++) - SWAP(char *, sep->se_argv[i], cp->se_argv[i]); + SWAP(char*, sep->se_argv[i], cp->se_argv[i]); #undef SWAP - sigprocmask(SIG_SETMASK, &oldmask, NULL); - freeconfig(cp); - } else { - sep = enter(cp); + restore_sigmask(&omask); + free_servtab_strings(cp); } + after_check: + /* cp->string_fields are consumed by insert_in_servlist() + * or freed at this point, cp itself is not yet freed. */ sep->se_checked = 1; + /* create new len_and_sockaddr */ switch (sep->se_family) { + struct sockaddr_un *sun; 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; - strncpy(sep->se_ctrladdr_un.sun_path, sep->se_service, n); - sep->se_ctrladdr_un.sun_family = AF_UNIX; - sep->se_ctrladdr_size = n + - sizeof sep->se_ctrladdr_un.sun_family; - setup(sep); + lsa = xzalloc_lsa(AF_UNIX); + sun = (struct sockaddr_un*)&lsa->u.sa; + safe_strncpy(sun->sun_path, sep->se_service, sizeof(sun->sun_path)); break; - case AF_INET: - sep->se_ctrladdr_in.sin_family = AF_INET; - sep->se_ctrladdr_size = sizeof sep->se_ctrladdr_in; - { - u_short port = htons(atoi(sep->se_service)); - - if (!port) { - struct servent *sp; - sp = getservbyname(sep->se_service, - sep->se_proto); - if (sp == 0) { - syslog(LOG_ERR, - "%s/%s: unknown service", - sep->se_service, sep->se_proto); - continue; - } - 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); + + default: /* case AF_INET, case AF_INET6 */ + n = bb_strtou(sep->se_service, NULL, 10); +#if ENABLE_FEATURE_INETD_RPC + if (is_rpc_service(sep)) { + sep->se_rpcprog = n; + if (errno) { /* se_service is not numeric */ + struct rpcent *rp = getrpcbyname(sep->se_service); + if (rp == NULL) { + bb_error_msg("%s: unknown rpc service", sep->se_service); + goto next_cp; } - sep->se_fd = -1; + sep->se_rpcprog = rp->r_number; } if (sep->se_fd == -1) - setup(sep); + prepare_socket_fd(sep); + if (sep->se_fd != -1) + register_rpc(sep); + goto next_cp; + } +#endif + /* what port to listen on? */ + port = htons(n); + if (errno || n > 0xffff) { /* se_service is not numeric */ + char protoname[4]; + struct servent *sp; + /* can result only in "tcp" or "udp": */ + safe_strncpy(protoname, sep->se_proto, 4); + sp = getservbyname(sep->se_service, protoname); + if (sp == NULL) { + bb_error_msg("%s/%s: unknown service", + sep->se_service, sep->se_proto); + goto next_cp; + } + port = sp->s_port; } + if (LONE_CHAR(sep->se_local_hostname, '*')) { + lsa = xzalloc_lsa(sep->se_family); + set_nport(lsa, port); + } else { + lsa = host_and_af2sockaddr(sep->se_local_hostname, + ntohs(port), sep->se_family); + if (!lsa) { + bb_error_msg("%s/%s: unknown host '%s'", + sep->se_service, sep->se_proto, + sep->se_local_hostname); + goto next_cp; + } + } + break; + } /* end of "switch (sep->se_family)" */ + + /* did lsa change? Then close/open */ + if (sep->se_lsa == NULL + || lsa->len != sep->se_lsa->len + || memcmp(&lsa->u.sa, &sep->se_lsa->u.sa, lsa->len) != 0 + ) { + remove_fd_from_set(sep->se_fd); + maybe_close(sep->se_fd); + free(sep->se_lsa); + sep->se_lsa = lsa; + sep->se_fd = -1; + } else { + free(lsa); } - } - if (fconfig) { - (void) fclose(fconfig); - fconfig = NULL; - } - /* - * Purge anything not looked at above. - */ - sigprocmask(SIG_SETMASK, &blockmask, &oldmask); - sepp = &servtab; - while ((sep = *sepp) != NULL) { + if (sep->se_fd == -1) + prepare_socket_fd(sep); + next_cp: + sep = cp->se_next; + free(cp); + cp = sep; + } /* end of "while (1) parse lines" */ + close_config_file(); + + /* Purge anything not looked at above - these are stale entries, + * new config file doesnt have them. */ + block_CHLD_HUP_ALRM(&omask); + sepp = &serv_list; + 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); - } + remove_fd_from_set(sep->se_fd); + maybe_close(sep->se_fd); +#if ENABLE_FEATURE_INETD_RPC + if (is_rpc_service(sep)) + unregister_rpc(sep); +#endif if (sep->se_family == AF_UNIX) - (void)unlink(sep->se_service); - freeconfig(sep); - free((char *)sep); + unlink(sep->se_service); + free_servtab_strings(sep); + free(sep); } - sigprocmask(SIG_SETMASK, &oldmask, NULL); + restore_sigmask(&omask); + ret: + errno = save_errno; } - - -static void -reapchild(int signum) +static void reap_child(int sig UNUSED_PARAM) { + pid_t pid; int status; - int pid; - struct servtab *sep; + servtab_t *sep; + int save_errno = errno; - (void)signum; for (;;) { - pid = wait3(&status, WNOHANG, (struct rusage *)0); + pid = wait_any_nohang(&status); if (pid <= 0) break; - for (sep = servtab; sep; sep = sep->se_next) - if (sep->se_wait == pid) { - 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; - FD_SET(sep->se_fd, &allsock); - nsock++; - } + for (sep = serv_list; sep; sep = sep->se_next) { + if (sep->se_wait != pid) + continue; + /* One of our "wait" services */ + if (WIFEXITED(status) && WEXITSTATUS(status)) + bb_error_msg("%s: exit status 0x%x", + sep->se_program, WEXITSTATUS(status)); + else if (WIFSIGNALED(status)) + bb_error_msg("%s: exit signal 0x%x", + sep->se_program, WTERMSIG(status)); + sep->se_wait = 1; + add_fd_to_set(sep->se_fd); + break; + } } + errno = save_errno; } -static void -retry(int signum) +static void retry_network_setup(int sig UNUSED_PARAM) { - struct servtab *sep; + int save_errno = errno; + servtab_t *sep; - (void)signum; - timingout = 0; - for (sep = servtab; sep; sep = sep->se_next) { + alarm_armed = 0; + for (sep = serv_list; sep; sep = sep->se_next) { if (sep->se_fd == -1) { - switch (sep->se_family) { - case AF_UNIX: - case AF_INET: - setup(sep); - break; - } + prepare_socket_fd(sep); +#if ENABLE_FEATURE_INETD_RPC + if (sep->se_fd != -1 && is_rpc_service(sep)) + register_rpc(sep); +#endif } } + errno = save_errno; } -static void -goaway(int signum) +static void clean_up_and_exit(int sig UNUSED_PARAM) { - struct servtab *sep; - - (void)signum; - for (sep = servtab; sep; sep = sep->se_next) - if (sep->se_fd != -1 && sep->se_family == AF_UNIX) - (void)unlink(sep->se_service); - (void)unlink(_PATH_INETDPID); - exit(0); -} + servtab_t *sep; + /* XXX signal race walking sep list */ + for (sep = serv_list; sep; sep = sep->se_next) { + if (sep->se_fd == -1) + continue; + switch (sep->se_family) { + case AF_UNIX: + unlink(sep->se_service); + break; + default: /* case AF_INET, AF_INET6 */ +#if ENABLE_FEATURE_INETD_RPC + if (sep->se_wait == 1 && is_rpc_service(sep)) + unregister_rpc(sep); /* XXX signal race */ +#endif + break; + } + if (ENABLE_FEATURE_CLEAN_UP) + close(sep->se_fd); + } + remove_pidfile(_PATH_INETDPID); + exit(EXIT_SUCCESS); +} -extern int -inetd_main(int argc, char *argv[]) +int inetd_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; +int inetd_main(int argc UNUSED_PARAM, char **argv) { - struct servtab *sep; + struct sigaction sa, saved_pipe_handler; + servtab_t *sep, *sep2; struct passwd *pwd; - struct group *grp = NULL; - struct sigaction sa; - int pid; - unsigned long opt; - char *sq; - gid_t gid; - -#ifdef INETD_UNSUPPORT_BILTIN -# define dofork 1 -#else - int dofork; - extern char **environ; -#endif - - gid = getgid(); - setgroups(1, &gid); + struct group *grp = grp; /* for compiler */ + int opt; + pid_t pid; + sigset_t omask; -#ifndef INETD_UNSUPPORT_BILTIN - Argv = argv; - if (environ == 0 || *environ == 0) - environ = argv; - while (*environ) - environ++; - LastArg = environ[-1] + strlen(environ[-1]); -#endif + INIT_G(); -#if defined(__uClinux__) - opt = bb_getopt_ulflags(argc, argv, "q:f", &sq); - if (!(opt & 2)) { - daemon(0, 0); - /* reexec for vfork() do continue parent */ - vfork_daemon_rexec(argc, argv, "-f"); - } -#else - opt = bb_getopt_ulflags(argc, argv, "q:", &sq); - daemon(0, 0); -#endif /* uClinux */ + real_uid = getuid(); + if (real_uid != 0) /* run by non-root user */ + config_filename = NULL; - if(opt & 1) { - global_queuelen = atoi(optarg); - if (global_queuelen < 8) global_queuelen=8; - } - argc -= optind; + opt_complementary = "R+:q+"; /* -q N, -R N */ + opt = getopt32(argv, "R:feq:", &max_concurrency, &global_queuelen); argv += optind; - - if (argc > 0) - CONFIG = argv[0]; - - openlog(bb_applet_name, LOG_PID | LOG_NOWAIT, LOG_DAEMON); - { - FILE *fp; - - if ((fp = fopen(_PATH_INETDPID, "w")) != NULL) { - fprintf(fp, "%u\n", getpid()); - (void)fclose(fp); - } + //argc -= optind; + if (argv[0]) + config_filename = argv[0]; + if (config_filename == NULL) + bb_error_msg_and_die("non-root must specify config file"); + if (!(opt & 2)) + bb_daemonize_or_rexec(0, argv - optind); + else + bb_sanitize_stdio(); + if (!(opt & 4)) { + openlog(applet_name, LOG_PID, LOG_DAEMON); + logmode = LOGMODE_SYSLOG; } -#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; + if (real_uid == 0) { + /* run by root, ensure groups vector gets trashed */ + gid_t gid = getgid(); + setgroups(1, &gid); } -#endif - config(0); + write_pidfile(_PATH_INETDPID); - sigemptyset(&emptymask); - sigemptyset(&blockmask); - sigaddset(&blockmask, SIGCHLD); - sigaddset(&blockmask, SIGHUP); - sigaddset(&blockmask, SIGALRM); + /* never fails under Linux (except if you pass it bad arguments) */ + getrlimit(RLIMIT_NOFILE, &rlim_ofile); + rlim_ofile_cur = rlim_ofile.rlim_cur; + if (rlim_ofile_cur == RLIM_INFINITY) /* ! */ + rlim_ofile_cur = OPEN_MAX; memset(&sa, 0, sizeof(sa)); - sa.sa_mask = blockmask; - sa.sa_handler = retry; - sigaction(SIGALRM, &sa, NULL); - 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); + /*sigemptyset(&sa.sa_mask); - memset did it */ + sigaddset(&sa.sa_mask, SIGALRM); + sigaddset(&sa.sa_mask, SIGCHLD); + sigaddset(&sa.sa_mask, SIGHUP); + sa.sa_handler = retry_network_setup; + sigaction_set(SIGALRM, &sa); + sa.sa_handler = reread_config_file; + sigaction_set(SIGHUP, &sa); + sa.sa_handler = reap_child; + sigaction_set(SIGCHLD, &sa); + sa.sa_handler = clean_up_and_exit; + sigaction_set(SIGTERM, &sa); + sa.sa_handler = clean_up_and_exit; + sigaction_set(SIGINT, &sa); sa.sa_handler = SIG_IGN; - sigaction(SIGPIPE, &sa, NULL); + sigaction(SIGPIPE, &sa, &saved_pipe_handler); - { - /* 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); - } + reread_config_file(SIGHUP); /* load config from file */ for (;;) { - int n, ctrl; - fd_set readable; - - if (nsock == 0) { - sigprocmask(SIG_BLOCK, &blockmask, NULL); - while (nsock == 0) - sigsuspend(&emptymask); - sigprocmask(SIG_SETMASK, &emptymask, NULL); - } - readable = allsock; - if ((n = select(maxsock + 1, &readable, (fd_set *)0, - (fd_set *)0, (struct timeval *)0)) <= 0) { - if (n < 0 && errno != EINTR) - syslog(LOG_WARNING, "select: %m"); - sleep(1); - continue; - } - for (sep = servtab; n && sep; sep = sep->se_next) - if (sep->se_fd != -1 && FD_ISSET(sep->se_fd, &readable)) { - n--; - if (!sep->se_wait && sep->se_socktype == SOCK_STREAM) { - /* Fixed AGC */ - fcntl(sep->se_fd, F_SETFL, O_NDELAY); - /* --------- */ - ctrl = accept(sep->se_fd, NULL, NULL); - fcntl(sep->se_fd, F_SETFL, 0); - if (ctrl < 0) { - if (errno == EINTR || errno == EWOULDBLOCK) - continue; - syslog(LOG_WARNING, "accept (for %s): %m", - sep->se_service); - continue; + int ready_fd_cnt; + int ctrl, accepted_fd, new_udp_fd; + fd_set readable; + + if (maxsock < 0) + recalculate_maxsock(); + + readable = allsock; /* struct copy */ + /* if there are no fds to wait on, we will block + * until signal wakes us up (maxsock == 0, but readable + * never contains fds 0 and 1...) */ + ready_fd_cnt = select(maxsock + 1, &readable, NULL, NULL, NULL); + if (ready_fd_cnt < 0) { + if (errno != EINTR) { + bb_perror_msg("select"); + sleep(1); } - } else + continue; + } + + for (sep = serv_list; ready_fd_cnt && sep; sep = sep->se_next) { + if (sep->se_fd == -1 || !FD_ISSET(sep->se_fd, &readable)) + continue; + + ready_fd_cnt--; ctrl = sep->se_fd; - sigprocmask(SIG_BLOCK, &blockmask, NULL); - pid = 0; -#ifndef INETD_UNSUPPORT_BILTIN - dofork = (sep->se_bi == 0 || sep->se_bi->bi_fork); -#endif - if (dofork) { - if (sep->se_count++ == 0) - (void)gettimeofday(&sep->se_time, - (struct timezone *)0); - else if (sep->se_count >= sep->se_max) { - struct timeval now; - - (void)gettimeofday(&now, (struct timezone *)0); - if (now.tv_sec - sep->se_time.tv_sec > - CNT_INTVL) { - sep->se_time = now; - sep->se_count = 1; - } else { - syslog(LOG_ERR, - "%s/%s server failing (looping), service terminated", - sep->se_service, sep->se_proto); - FD_CLR(sep->se_fd, &allsock); - (void) close(sep->se_fd); - sep->se_fd = -1; - sep->se_count = 0; - nsock--; - sigprocmask(SIG_SETMASK, &emptymask, - NULL); - if (!timingout) { - timingout = 1; - alarm(RETRYTIME); + accepted_fd = -1; + new_udp_fd = -1; + if (!sep->se_wait) { + if (sep->se_socktype == SOCK_STREAM) { + ctrl = accepted_fd = accept(sep->se_fd, NULL, NULL); + if (ctrl < 0) { + if (errno != EINTR) + bb_perror_msg("accept (for %s)", sep->se_service); + continue; + } + } + /* "nowait" udp */ + if (sep->se_socktype == SOCK_DGRAM + && sep->se_family != AF_UNIX + ) { +/* How udp "nowait" works: + * child peeks at (received and buffered by kernel) UDP packet, + * performs connect() on the socket so that it is linked only + * to this peer. But this also affects parent, because descriptors + * are shared after fork() a-la dup(). When parent performs + * select(), it will see this descriptor connected to the peer (!) + * and still readable, will act on it and mess things up + * (can create many copies of same child, etc). + * Parent must create and use new socket instead. */ + new_udp_fd = socket(sep->se_family, SOCK_DGRAM, 0); + if (new_udp_fd < 0) { /* error: eat packet, forget about it */ + udp_err: + recv(sep->se_fd, line, LINE_SIZE, MSG_DONTWAIT); + continue; + } + setsockopt_reuseaddr(new_udp_fd); + /* TODO: better do bind after vfork in parent, + * so that we don't have two wildcard bound sockets + * even for a brief moment? */ + if (bind(new_udp_fd, &sep->se_lsa->u.sa, sep->se_lsa->len) < 0) { + close(new_udp_fd); + goto udp_err; } - continue; } } - pid = fork(); - } - if (pid < 0) { - syslog(LOG_ERR, "fork: %m"); - if (sep->se_socktype == SOCK_STREAM) - close(ctrl); - sigprocmask(SIG_SETMASK, &emptymask, NULL); - sleep(1); - continue; - } - if (pid && sep->se_wait) { - sep->se_wait = pid; - FD_CLR(sep->se_fd, &allsock); - nsock--; - } - sigprocmask(SIG_SETMASK, &emptymask, NULL); - if (pid == 0) { -#ifndef INETD_UNSUPPORT_BILTIN - if (sep->se_bi) - (*sep->se_bi->bi_fn)(ctrl, sep); - else + + block_CHLD_HUP_ALRM(&omask); + pid = 0; +#ifdef INETD_BUILTINS_ENABLED + /* do we need to fork? */ + if (sep->se_builtin == NULL + || (sep->se_socktype == SOCK_STREAM + && sep->se_builtin->bi_fork)) +#endif + { + if (sep->se_max != 0) { + if (++sep->se_count == 1) + sep->se_time = monotonic_sec(); + else if (sep->se_count >= sep->se_max) { + unsigned now = monotonic_sec(); + /* did we accumulate se_max connects too quickly? */ + if (now - sep->se_time <= CNT_INTERVAL) { + bb_error_msg("%s/%s: too many connections, pausing", + sep->se_service, sep->se_proto); + remove_fd_from_set(sep->se_fd); + close(sep->se_fd); + sep->se_fd = -1; + sep->se_count = 0; + rearm_alarm(); /* will revive it in RETRYTIME sec */ + restore_sigmask(&omask); + maybe_close(accepted_fd); + continue; /* -> check next fd in fd set */ + } + sep->se_count = 0; + } + } + /* on NOMMU, streamed chargen + * builtin wouldn't work, but it is + * not allowed on NOMMU (ifdefed out) */ +#ifdef INETD_BUILTINS_ENABLED + if (BB_MMU && sep->se_builtin) + pid = fork(); + else #endif - { - if ((pwd = getpwnam(sep->se_user)) == NULL) { - syslog_err_and_discard_dg( - sep->se_socktype, - "getpwnam: %s: No such user", - sep->se_user); + pid = vfork(); + + if (pid < 0) { /* fork error */ + bb_perror_msg("fork"); + sleep(1); + restore_sigmask(&omask); + maybe_close(accepted_fd); + continue; /* -> check next fd in fd set */ } - if (sep->se_group && - (grp = getgrnam(sep->se_group)) == NULL) { - syslog_err_and_discard_dg( - sep->se_socktype, - "getgrnam: %s: No such group", - sep->se_group); + if (pid == 0) + pid--; /* -1: "we did fork and we are child" */ + } + /* if pid == 0 here, we never forked */ + + if (pid > 0) { /* parent */ + if (sep->se_wait) { + /* tcp wait: we passed listening socket to child, + * will wait for child to terminate */ + sep->se_wait = pid; + remove_fd_from_set(sep->se_fd); } - /* - * Ok. There are four cases here: - * 1. nonroot user, no group specified - * 2. nonroot user, some group specified - * 3. root user, no group specified - * 4. root user, some group specified - * In cases 2 and 4 we setgid to the specified - * group. In cases 1 and 2 we run initgroups - * to run with the groups of the given user. - * In case 4 we do setgroups to run with the - * given group. In case 3 we do nothing. - */ - if (pwd->pw_uid) { - if (sep->se_group) - pwd->pw_gid = grp->gr_gid; - setgid((gid_t)pwd->pw_gid); - initgroups(pwd->pw_name, pwd->pw_gid); - setuid((uid_t)pwd->pw_uid); - } else if (sep->se_group) { - setgid((gid_t)grp->gr_gid); - setgroups(1, &grp->gr_gid); + if (new_udp_fd >= 0) { + /* udp nowait: child connected the socket, + * we created and will use new, unconnected one */ + xmove_fd(new_udp_fd, sep->se_fd); } - dup2(ctrl, 0); - close(ctrl); - dup2(0, 1); - dup2(0, 2); -#ifdef RLIMIT_NOFILE - if (rlim_ofile.rlim_cur != rlim_ofile_cur) { - if (setrlimit(RLIMIT_NOFILE, - &rlim_ofile) < 0) - syslog(LOG_ERR,"setrlimit: %m"); + restore_sigmask(&omask); + maybe_close(accepted_fd); + continue; /* -> check next fd in fd set */ + } + + /* we are either child or didn't vfork at all */ +#ifdef INETD_BUILTINS_ENABLED + if (sep->se_builtin) { + if (pid) { /* "pid" is -1: we did vfork */ + close(sep->se_fd); /* listening socket */ + logmode = LOGMODE_NONE; /* make xwrite etc silent */ } + restore_sigmask(&omask); + if (sep->se_socktype == SOCK_STREAM) + sep->se_builtin->bi_stream_fn(ctrl, sep); + else + sep->se_builtin->bi_dgram_fn(ctrl, sep); + if (pid) /* we did vfork */ + _exit(EXIT_FAILURE); + maybe_close(accepted_fd); + continue; /* -> check next fd in fd set */ + } #endif - for (ctrl = rlim_ofile_cur-1; --ctrl > 2; ) - (void)close(ctrl); - - memset(&sa, 0, sizeof(sa)); - sa.sa_handler = SIG_DFL; - sigaction(SIGPIPE, &sa, NULL); - - execv(sep->se_server, sep->se_argv); - syslog_err_and_discard_dg(sep->se_socktype, - "execv %s: %m", sep->se_server); + /* child */ + setsid(); + /* "nowait" udp */ + if (new_udp_fd >= 0) { + len_and_sockaddr *lsa = xzalloc_lsa(sep->se_family); + /* peek at the packet and remember peer addr */ + int r = recvfrom(ctrl, NULL, 0, MSG_PEEK|MSG_DONTWAIT, + &lsa->u.sa, &lsa->len); + if (r < 0) + goto do_exit1; + /* make this socket "connected" to peer addr: + * only packets from this peer will be recv'ed, + * and bare write()/send() will work on it */ + connect(ctrl, &lsa->u.sa, lsa->len); + free(lsa); } - } - if (!sep->se_wait && sep->se_socktype == SOCK_STREAM) - close(ctrl); - } - } + /* prepare env and exec program */ + pwd = getpwnam(sep->se_user); + if (pwd == NULL) { + bb_error_msg("%s: no such %s", sep->se_user, "user"); + goto do_exit1; + } + if (sep->se_group && (grp = getgrnam(sep->se_group)) == NULL) { + bb_error_msg("%s: no such %s", sep->se_group, "group"); + goto do_exit1; + } + if (real_uid != 0 && real_uid != pwd->pw_uid) { + /* a user running private inetd */ + bb_error_msg("non-root must run services as himself"); + goto do_exit1; + } + if (pwd->pw_uid) { + if (sep->se_group) + pwd->pw_gid = grp->gr_gid; + /* initgroups, setgid, setuid: */ + change_identity(pwd); + } else if (sep->se_group) { + xsetgid(grp->gr_gid); + setgroups(1, &grp->gr_gid); + } + if (rlim_ofile.rlim_cur != rlim_ofile_cur) + if (setrlimit(RLIMIT_NOFILE, &rlim_ofile) < 0) + bb_perror_msg("setrlimit"); + closelog(); + xmove_fd(ctrl, 0); + xdup2(0, 1); + xdup2(0, 2); + /* NB: among others, this loop closes listening socket + * for nowait stream children */ + for (sep2 = serv_list; sep2; sep2 = sep2->se_next) + maybe_close(sep2->se_fd); + sigaction_set(SIGPIPE, &saved_pipe_handler); + restore_sigmask(&omask); + BB_EXECVP(sep->se_program, sep->se_argv); + bb_perror_msg("exec %s", sep->se_program); + do_exit1: + /* eat packet in udp case */ + if (sep->se_socktype != SOCK_STREAM) + recv(0, line, LINE_SIZE, MSG_DONTWAIT); + _exit(EXIT_FAILURE); + } /* for (sep = servtab...) */ + } /* for (;;) */ } +#if !BB_MMU +static const char *const cat_args[] = { "cat", NULL }; +#endif /* * Internet services provided internally by inetd: */ -#define BUFSIZE 4096 - -#ifdef CONFIG_FEATURE_INETD_SUPPORT_BILTIN_ECHO -/* Echo service -- echo data back */ -static void -echo_stream(int s, struct servtab *sep) +#if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_ECHO +/* Echo service -- echo data back. */ +/* ARGSUSED */ +static void echo_stream(int s, servtab_t *sep UNUSED_PARAM) { - char buffer[BUFSIZE]; - int i; - - setproctitle(sep->se_service, s); - while ((i = read(s, buffer, sizeof(buffer))) > 0 && - write(s, buffer, i) > 0) - ; - exit(0); +#if BB_MMU + while (1) { + ssize_t sz = safe_read(s, line, LINE_SIZE); + if (sz <= 0) + break; + xwrite(s, line, sz); + } +#else + /* We are after vfork here! */ + /* move network socket to stdin/stdout */ + xmove_fd(s, STDIN_FILENO); + xdup2(STDIN_FILENO, STDOUT_FILENO); + /* no error messages please... */ + close(STDERR_FILENO); + xopen(bb_dev_null, O_WRONLY); + BB_EXECVP("cat", (char**)cat_args); + /* on failure we return to main, which does exit(EXIT_FAILURE) */ +#endif } - -/* Echo service -- echo data back */ -static void -echo_dg(int s, struct servtab *sep) +static void echo_dg(int s, servtab_t *sep) { - char buffer[BUFSIZE]; - int i; - size_t size; - struct sockaddr sa; - - (void)sep; - - size = sizeof(sa); - if ((i = recvfrom(s, buffer, sizeof(buffer), 0, &sa, &size)) < 0) - return; - (void) sendto(s, buffer, i, 0, &sa, sizeof(sa)); + enum { BUFSIZE = 12*1024 }; /* for jumbo sized packets! :) */ + char *buf = xmalloc(BUFSIZE); /* too big for stack */ + int sz; + len_and_sockaddr *lsa = alloca(LSA_LEN_SIZE + sep->se_lsa->len); + + lsa->len = sep->se_lsa->len; + /* dgram builtins are non-forking - DONT BLOCK! */ + sz = recvfrom(s, buf, BUFSIZE, MSG_DONTWAIT, &lsa->u.sa, &lsa->len); + if (sz > 0) + sendto(s, buf, sz, 0, &lsa->u.sa, lsa->len); + free(buf); } -#endif /* CONFIG_FEATURE_INETD_SUPPORT_BILTIN_ECHO */ +#endif /* FEATURE_INETD_SUPPORT_BUILTIN_ECHO */ -#ifdef CONFIG_FEATURE_INETD_SUPPORT_BILTIN_DISCARD -/* Discard service -- ignore data */ -static void -discard_stream(int s, struct servtab *sep) +#if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_DISCARD +/* Discard service -- ignore data. */ +/* ARGSUSED */ +static void discard_stream(int s, servtab_t *sep UNUSED_PARAM) { - char buffer[BUFSIZE]; - - setproctitle(sep->se_service, s); - while ((errno = 0, read(s, buffer, sizeof(buffer)) > 0) || - errno == EINTR) - ; - exit(0); +#if BB_MMU + while (safe_read(s, line, LINE_SIZE) > 0) + continue; +#else + /* We are after vfork here! */ + /* move network socket to stdin */ + xmove_fd(s, STDIN_FILENO); + /* discard output */ + close(STDOUT_FILENO); + xopen(bb_dev_null, O_WRONLY); + /* no error messages please... */ + xdup2(STDOUT_FILENO, STDERR_FILENO); + BB_EXECVP("cat", (char**)cat_args); + /* on failure we return to main, which does exit(EXIT_FAILURE) */ +#endif } - -/* Discard service -- ignore data */ -static void -discard_dg(int s, struct servtab *sep) +/* ARGSUSED */ +static void discard_dg(int s, servtab_t *sep UNUSED_PARAM) { - char buffer[BUFSIZE]; - (void)sep; - read(s, buffer, sizeof(buffer)); + /* dgram builtins are non-forking - DONT BLOCK! */ + recv(s, line, LINE_SIZE, MSG_DONTWAIT); } -#endif /* CONFIG_FEATURE_INETD_SUPPORT_BILTIN_DISCARD */ +#endif /* FEATURE_INETD_SUPPORT_BUILTIN_DISCARD */ -#ifdef CONFIG_FEATURE_INETD_SUPPORT_BILTIN_CHARGEN -#include <ctype.h> +#if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_CHARGEN #define LINESIZ 72 -static char ring[128]; -static char *endring; - -static void -initring(void) +static void init_ring(void) { int i; - endring = ring; - + end_ring = ring; for (i = 0; i <= 128; ++i) if (isprint(i)) - *endring++ = i; + *end_ring++ = i; } - -/* Character generator */ -static void -chargen_stream(int s, struct servtab *sep) +/* Character generator. MMU arches only. */ +/* ARGSUSED */ +static void chargen_stream(int s, servtab_t *sep UNUSED_PARAM) { char *rs; int len; - char text[LINESIZ+2]; - - setproctitle(sep->se_service, s); + char text[LINESIZ + 2]; - if (!endring) { - initring(); + if (!end_ring) { + init_ring(); rs = ring; } text[LINESIZ] = '\r'; text[LINESIZ + 1] = '\n'; - for (rs = ring;;) { - if ((len = endring - rs) >= LINESIZ) - BCOPY(rs, text, LINESIZ); + rs = ring; + for (;;) { + len = end_ring - rs; + if (len >= LINESIZ) + memmove(text, rs, LINESIZ); else { - BCOPY(rs, text, len); - BCOPY(ring, text + len, LINESIZ - len); + memmove(text, rs, len); + memmove(text + len, ring, LINESIZ - len); } - if (++rs == endring) + if (++rs == end_ring) rs = ring; - if (write(s, text, sizeof(text)) != sizeof(text)) - break; + xwrite(s, text, sizeof(text)); } - exit(0); } - -/* Character generator */ -static void -chargen_dg(int s, struct servtab *sep) +/* ARGSUSED */ +static void chargen_dg(int s, servtab_t *sep) { - struct sockaddr sa; - static char *rs; - size_t len, size; - char text[LINESIZ+2]; + int len; + char text[LINESIZ + 2]; + len_and_sockaddr *lsa = alloca(LSA_LEN_SIZE + sep->se_lsa->len); - (void)sep; + /* Eat UDP packet which started it all */ + /* dgram builtins are non-forking - DONT BLOCK! */ + lsa->len = sep->se_lsa->len; + if (recvfrom(s, text, sizeof(text), MSG_DONTWAIT, &lsa->u.sa, &lsa->len) < 0) + return; - if (endring == 0) { - initring(); - rs = ring; + if (!end_ring) { + init_ring(); + ring_pos = ring; } - size = sizeof(sa); - if (recvfrom(s, text, sizeof(text), 0, &sa, &size) < 0) - return; - - if ((len = endring - rs) >= LINESIZ) - BCOPY(rs, text, LINESIZ); + len = end_ring - ring_pos; + if (len >= LINESIZ) + memmove(text, ring_pos, LINESIZ); else { - BCOPY(rs, text, len); - BCOPY(ring, text + len, LINESIZ - len); + memmove(text, ring_pos, len); + memmove(text + len, ring, LINESIZ - len); } - if (++rs == endring) - rs = ring; + if (++ring_pos == end_ring) + ring_pos = ring; text[LINESIZ] = '\r'; text[LINESIZ + 1] = '\n'; - (void) sendto(s, text, sizeof(text), 0, &sa, sizeof(sa)); + sendto(s, text, sizeof(text), 0, &lsa->u.sa, lsa->len); } -#endif /* CONFIG_FEATURE_INETD_SUPPORT_BILTIN_CHARGEN */ +#endif /* FEATURE_INETD_SUPPORT_BUILTIN_CHARGEN */ -#ifdef CONFIG_FEATURE_INETD_SUPPORT_BILTIN_TIME +#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 @@ -1222,81 +1536,57 @@ chargen_dg(int s, struct servtab *sep) * we must add 2208988800 seconds to this figure to make up for * some seventy years Bell Labs was asleep. */ - -static long -machtime(void) +static uint32_t machtime(void) { struct timeval tv; - if (gettimeofday(&tv, (struct timezone *)0) < 0) { - fprintf(stderr, "Unable to get time of day\n"); - return (0L); - } - return (htonl((long)tv.tv_sec + 2208988800UL)); + gettimeofday(&tv, NULL); + return htonl((uint32_t)(tv.tv_sec + 2208988800)); } - -static void -machtime_stream(int s, struct servtab *sep) +/* ARGSUSED */ +static void machtime_stream(int s, servtab_t *sep UNUSED_PARAM) { - long result; - (void)sep; + uint32_t result; result = machtime(); - write(s, (char *) &result, sizeof(result)); + full_write(s, &result, sizeof(result)); } - -static void -machtime_dg(int s, struct servtab *sep) +static void machtime_dg(int s, servtab_t *sep) { - long result; - struct sockaddr sa; - size_t size; - (void)sep; + uint32_t result; + len_and_sockaddr *lsa = alloca(LSA_LEN_SIZE + sep->se_lsa->len); - size = sizeof(sa); - if (recvfrom(s, (char *)&result, sizeof(result), 0, &sa, &size) < 0) + lsa->len = sep->se_lsa->len; + if (recvfrom(s, line, LINE_SIZE, MSG_DONTWAIT, &lsa->u.sa, &lsa->len) < 0) return; + result = machtime(); - (void) sendto(s, (char *) &result, sizeof(result), 0, &sa, sizeof(sa)); + sendto(s, &result, sizeof(result), 0, &lsa->u.sa, lsa->len); } -#endif /* CONFIG_FEATURE_INETD_SUPPORT_BILTIN_TIME */ +#endif /* FEATURE_INETD_SUPPORT_BUILTIN_TIME */ -#ifdef CONFIG_FEATURE_INETD_SUPPORT_BILTIN_DAYTIME +#if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_DAYTIME /* Return human-readable time of day */ -static int -human_readable_time_sprintf(char *buffer) +/* ARGSUSED */ +static void daytime_stream(int s, servtab_t *sep UNUSED_PARAM) { - time_t clocc = time(NULL); + time_t t; - return sprintf(buffer, "%.24s\r\n", ctime(&clocc)); + t = time(NULL); + fdprintf(s, "%.24s\r\n", ctime(&t)); } - -static void -daytime_stream(int s, struct servtab *sep) +static void daytime_dg(int s, servtab_t *sep) { - char buffer[256]; - size_t st = human_readable_time_sprintf(buffer); - - (void)sep; + time_t t; + len_and_sockaddr *lsa = alloca(LSA_LEN_SIZE + sep->se_lsa->len); - write(s, buffer, st); -} - -/* Return human-readable time of day */ -static void -daytime_dg(int s, struct servtab *sep) -{ - char buffer[256]; - struct sockaddr sa; - size_t size; - - (void)sep; - - size = sizeof(sa); - if (recvfrom(s, buffer, sizeof(buffer), 0, &sa, &size) < 0) + lsa->len = sep->se_lsa->len; + if (recvfrom(s, line, LINE_SIZE, MSG_DONTWAIT, &lsa->u.sa, &lsa->len) < 0) return; - size = human_readable_time_sprintf(buffer); - sendto(s, buffer, size, 0, &sa, sizeof(sa)); + + t = time(NULL); + sprintf(line, "%.24s\r\n", ctime(&t)); + sendto(s, line, strlen(line), 0, &lsa->u.sa, lsa->len); } -#endif /* CONFIG_FEATURE_INETD_SUPPORT_BILTIN_DAYTIME */ +#endif /* FEATURE_INETD_SUPPORT_BUILTIN_DAYTIME */ |