1 | /* vi: set sw=4 ts=4: */
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2 | /* $Slackware: inetd.c 1.79s 2001/02/06 13:18:00 volkerdi Exp $ */
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3 | /* $OpenBSD: inetd.c,v 1.79 2001/01/30 08:30:57 deraadt Exp $ */
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4 | /* $NetBSD: inetd.c,v 1.11 1996/02/22 11:14:41 mycroft Exp $ */
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5 | /* Busybox port by Vladimir Oleynik (C) 2001-2005 <dzo@simtreas.ru> */
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6 | /* IPv6 support, many bug fixes by Denys Vlasenko (c) 2008 */
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7 | /*
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8 | * Copyright (c) 1983,1991 The Regents of the University of California.
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9 | * All rights reserved.
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10 | *
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11 | * Redistribution and use in source and binary forms, with or without
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12 | * modification, are permitted provided that the following conditions
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13 | * are met:
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14 | * 1. Redistributions of source code must retain the above copyright
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15 | * notice, this list of conditions and the following disclaimer.
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16 | * 2. Redistributions in binary form must reproduce the above copyright
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17 | * notice, this list of conditions and the following disclaimer in the
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18 | * documentation and/or other materials provided with the distribution.
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19 | * 3. All advertising materials mentioning features or use of this software
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20 | * must display the following acknowledgement:
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21 | * This product includes software developed by the University of
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22 | * California, Berkeley and its contributors.
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23 | * 4. Neither the name of the University nor the names of its contributors
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24 | * may be used to endorse or promote products derived from this software
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25 | * without specific prior written permission.
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26 | *
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27 | * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS "AS IS" AND
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28 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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29 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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30 | * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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31 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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32 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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33 | * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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34 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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35 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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36 | * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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37 | * SUCH DAMAGE.
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38 | */
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39 |
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40 | /* Inetd - Internet super-server
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41 | *
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42 | * This program invokes configured services when a connection
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43 | * from a peer is established or a datagram arrives.
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44 | * Connection-oriented services are invoked each time a
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45 | * connection is made, by creating a process. This process
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46 | * is passed the connection as file descriptor 0 and is
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47 | * expected to do a getpeername to find out peer's host
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48 | * and port.
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49 | * Datagram oriented services are invoked when a datagram
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50 | * arrives; a process is created and passed a pending message
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51 | * on file descriptor 0. peer's address can be obtained
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52 | * using recvfrom.
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53 | *
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54 | * Inetd uses a configuration file which is read at startup
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55 | * and, possibly, at some later time in response to a hangup signal.
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56 | * The configuration file is "free format" with fields given in the
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57 | * order shown below. Continuation lines for an entry must begin with
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58 | * a space or tab. All fields must be present in each entry.
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59 | *
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60 | * service_name must be in /etc/services
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61 | * socket_type stream/dgram/raw/rdm/seqpacket
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62 | * protocol must be in /etc/protocols
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63 | * (usually "tcp" or "udp")
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64 | * wait/nowait[.max] single-threaded/multi-threaded, max #
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65 | * user[.group] or user[:group] user/group to run daemon as
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66 | * server_program full path name
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67 | * server_program_arguments maximum of MAXARGS (20)
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68 | *
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69 | * For RPC services
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70 | * service_name/version must be in /etc/rpc
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71 | * socket_type stream/dgram/raw/rdm/seqpacket
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72 | * rpc/protocol "rpc/tcp" etc
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73 | * wait/nowait[.max] single-threaded/multi-threaded
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74 | * user[.group] or user[:group] user to run daemon as
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75 | * server_program full path name
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76 | * server_program_arguments maximum of MAXARGS (20)
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77 | *
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78 | * For non-RPC services, the "service name" can be of the form
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79 | * hostaddress:servicename, in which case the hostaddress is used
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80 | * as the host portion of the address to listen on. If hostaddress
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81 | * consists of a single '*' character, INADDR_ANY is used.
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82 | *
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83 | * A line can also consist of just
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84 | * hostaddress:
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85 | * where hostaddress is as in the preceding paragraph. Such a line must
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86 | * have no further fields; the specified hostaddress is remembered and
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87 | * used for all further lines that have no hostaddress specified,
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88 | * until the next such line (or EOF). (This is why * is provided to
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89 | * allow explicit specification of INADDR_ANY.) A line
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90 | * *:
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91 | * is implicitly in effect at the beginning of the file.
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92 | *
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93 | * The hostaddress specifier may (and often will) contain dots;
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94 | * the service name must not.
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95 | *
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96 | * For RPC services, host-address specifiers are accepted and will
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97 | * work to some extent; however, because of limitations in the
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98 | * portmapper interface, it will not work to try to give more than
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99 | * one line for any given RPC service, even if the host-address
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100 | * specifiers are different.
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101 | *
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102 | * Comment lines are indicated by a '#' in column 1.
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103 | */
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104 |
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105 | /* inetd rules for passing file descriptors to children
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106 | * (http://www.freebsd.org/cgi/man.cgi?query=inetd):
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107 | *
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108 | * The wait/nowait entry specifies whether the server that is invoked by
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109 | * inetd will take over the socket associated with the service access point,
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110 | * and thus whether inetd should wait for the server to exit before listen-
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111 | * ing for new service requests. Datagram servers must use "wait", as
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112 | * they are always invoked with the original datagram socket bound to the
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113 | * specified service address. These servers must read at least one datagram
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114 | * from the socket before exiting. If a datagram server connects to its
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115 | * peer, freeing the socket so inetd can receive further messages on the
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116 | * socket, it is said to be a "multi-threaded" server; it should read one
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117 | * datagram from the socket and create a new socket connected to the peer.
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118 | * It should fork, and the parent should then exit to allow inetd to check
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119 | * for new service requests to spawn new servers. Datagram servers which
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120 | * process all incoming datagrams on a socket and eventually time out are
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121 | * said to be "single-threaded". The comsat(8), biff(1) and talkd(8)
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122 | * utilities are both examples of the latter type of datagram server. The
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123 | * tftpd(8) utility is an example of a multi-threaded datagram server.
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124 | *
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125 | * Servers using stream sockets generally are multi-threaded and use the
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126 | * "nowait" entry. Connection requests for these services are accepted by
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127 | * inetd, and the server is given only the newly-accepted socket connected
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128 | * to a client of the service. Most stream-based services operate in this
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129 | * manner. Stream-based servers that use "wait" are started with the lis-
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130 | * tening service socket, and must accept at least one connection request
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131 | * before exiting. Such a server would normally accept and process incoming
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132 | * connection requests until a timeout.
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133 | */
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134 |
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135 | /* Despite of above doc saying that dgram services must use "wait",
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136 | * "udp nowait" servers are implemented in busyboxed inetd.
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137 | * IPv6 addresses are also implemented. However, they may look ugly -
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138 | * ":::service..." means "address '::' (IPv6 wildcard addr)":"service"...
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139 | * You have to put "tcp6"/"udp6" in protocol field to select IPv6.
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140 | */
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141 |
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142 | /* Here's the scoop concerning the user[:group] feature:
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143 | * 1) group is not specified:
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144 | * a) user = root: NO setuid() or setgid() is done
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145 | * b) other: initgroups(name, primary group)
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146 | * setgid(primary group as found in passwd)
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147 | * setuid()
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148 | * 2) group is specified:
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149 | * a) user = root: setgid(specified group)
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150 | * NO initgroups()
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151 | * NO setuid()
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152 | * b) other: initgroups(name, specified group)
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153 | * setgid(specified group)
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154 | * setuid()
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155 | */
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156 |
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157 | //usage:#define inetd_trivial_usage
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158 | //usage: "[-fe] [-q N] [-R N] [CONFFILE]"
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159 | //usage:#define inetd_full_usage "\n\n"
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160 | //usage: "Listen for network connections and launch programs\n"
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161 | //usage: "\n -f Run in foreground"
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162 | //usage: "\n -e Log to stderr"
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163 | //usage: "\n -q N Socket listen queue (default: 128)"
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164 | //usage: "\n -R N Pause services after N connects/min"
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165 | //usage: "\n (default: 0 - disabled)"
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166 |
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167 | #include <syslog.h>
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168 | #include <sys/resource.h> /* setrlimit */
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169 | #include <sys/socket.h> /* un.h may need this */
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170 | #include <sys/un.h>
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171 |
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172 | #include "libbb.h"
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173 | #include "common_bufsiz.h"
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174 |
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175 | #if ENABLE_FEATURE_INETD_RPC
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176 | # if defined(__UCLIBC__) && ! defined(__UCLIBC_HAS_RPC__)
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177 | # error "You need to build uClibc with UCLIBC_HAS_RPC for NFS support"
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178 | # endif
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179 | # include <rpc/rpc.h>
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180 | # include <rpc/pmap_clnt.h>
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181 | #endif
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182 |
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183 | #if !BB_MMU
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184 | /* stream version of chargen is forking but not execing,
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185 | * can't do that (easily) on NOMMU */
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186 | #undef ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_CHARGEN
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187 | #define ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_CHARGEN 0
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188 | #endif
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189 |
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190 | #define CNT_INTERVAL 60 /* servers in CNT_INTERVAL sec. */
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191 | #define RETRYTIME 60 /* retry after bind or server fail */
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192 |
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193 | // TODO: explain, or get rid of setrlimit games
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194 |
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195 | #ifndef RLIMIT_NOFILE
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196 | #define RLIMIT_NOFILE RLIMIT_OFILE
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197 | #endif
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198 |
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199 | #ifndef OPEN_MAX
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200 | #define OPEN_MAX 64
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201 | #endif
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202 |
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203 | /* Reserve some descriptors, 3 stdio + at least: 1 log, 1 conf. file */
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204 | #define FD_MARGIN 8
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205 |
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206 | #if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_DISCARD \
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207 | || ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_ECHO \
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208 | || ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_CHARGEN \
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209 | || ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_TIME \
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210 | || ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_DAYTIME
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211 | # define INETD_BUILTINS_ENABLED
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212 | #endif
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213 |
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214 | typedef struct servtab_t {
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215 | /* The most frequently referenced one: */
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216 | int se_fd; /* open descriptor */
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217 | /* NB: 'biggest fields last' saves on code size (~250 bytes) */
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218 | /* [addr:]service socktype proto wait user[:group] prog [args] */
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219 | char *se_local_hostname; /* addr to listen on */
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220 | char *se_service; /* "80" or "www" or "mount/2[-3]" */
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221 | /* socktype is in se_socktype */ /* "stream" "dgram" "raw" "rdm" "seqpacket" */
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222 | char *se_proto; /* "unix" or "[rpc/]tcp[6]" */
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223 | #if ENABLE_FEATURE_INETD_RPC
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224 | int se_rpcprog; /* rpc program number */
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225 | int se_rpcver_lo; /* rpc program lowest version */
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226 | int se_rpcver_hi; /* rpc program highest version */
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227 | #define is_rpc_service(sep) ((sep)->se_rpcver_lo != 0)
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228 | #else
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229 | #define is_rpc_service(sep) 0
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230 | #endif
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231 | pid_t se_wait; /* 0:"nowait", 1:"wait", >1:"wait" */
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232 | /* and waiting for this pid */
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233 | socktype_t se_socktype; /* SOCK_STREAM/DGRAM/RDM/... */
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234 | family_t se_family; /* AF_UNIX/INET[6] */
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235 | /* se_proto_no is used by RPC code only... hmm */
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236 | smallint se_proto_no; /* IPPROTO_TCP/UDP, n/a for AF_UNIX */
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237 | smallint se_checked; /* looked at during merge */
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238 | unsigned se_max; /* allowed instances per minute */
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239 | unsigned se_count; /* number started since se_time */
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240 | unsigned se_time; /* when we started counting */
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241 | char *se_user; /* user name to run as */
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242 | char *se_group; /* group name to run as, can be NULL */
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243 | #ifdef INETD_BUILTINS_ENABLED
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244 | const struct builtin *se_builtin; /* if built-in, description */
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245 | #endif
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246 | struct servtab_t *se_next;
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247 | len_and_sockaddr *se_lsa;
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248 | char *se_program; /* server program */
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249 | #define MAXARGV 20
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250 | char *se_argv[MAXARGV + 1]; /* program arguments */
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251 | } servtab_t;
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252 |
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253 | #ifdef INETD_BUILTINS_ENABLED
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254 | /* Echo received data */
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255 | #if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_ECHO
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256 | static void FAST_FUNC echo_stream(int, servtab_t *);
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257 | static void FAST_FUNC echo_dg(int, servtab_t *);
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258 | #endif
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259 | /* Internet /dev/null */
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260 | #if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_DISCARD
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261 | static void FAST_FUNC discard_stream(int, servtab_t *);
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262 | static void FAST_FUNC discard_dg(int, servtab_t *);
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263 | #endif
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264 | /* Return 32 bit time since 1900 */
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265 | #if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_TIME
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266 | static void FAST_FUNC machtime_stream(int, servtab_t *);
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267 | static void FAST_FUNC machtime_dg(int, servtab_t *);
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268 | #endif
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269 | /* Return human-readable time */
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270 | #if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_DAYTIME
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271 | static void FAST_FUNC daytime_stream(int, servtab_t *);
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272 | static void FAST_FUNC daytime_dg(int, servtab_t *);
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273 | #endif
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274 | /* Familiar character generator */
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275 | #if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_CHARGEN
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276 | static void FAST_FUNC chargen_stream(int, servtab_t *);
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277 | static void FAST_FUNC chargen_dg(int, servtab_t *);
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278 | #endif
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279 |
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280 | struct builtin {
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281 | /* NB: not necessarily NUL terminated */
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282 | char bi_service7[7]; /* internally provided service name */
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283 | uint8_t bi_fork; /* 1 if stream fn should run in child */
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284 | void (*bi_stream_fn)(int, servtab_t *) FAST_FUNC;
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285 | void (*bi_dgram_fn)(int, servtab_t *) FAST_FUNC;
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286 | };
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287 |
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288 | static const struct builtin builtins[] = {
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289 | #if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_ECHO
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290 | { "echo", 1, echo_stream, echo_dg },
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291 | #endif
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292 | #if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_DISCARD
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293 | { "discard", 1, discard_stream, discard_dg },
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294 | #endif
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295 | #if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_CHARGEN
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296 | { "chargen", 1, chargen_stream, chargen_dg },
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297 | #endif
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298 | #if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_TIME
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299 | { "time", 0, machtime_stream, machtime_dg },
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300 | #endif
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301 | #if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_DAYTIME
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302 | { "daytime", 0, daytime_stream, daytime_dg },
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303 | #endif
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304 | };
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305 | #endif /* INETD_BUILTINS_ENABLED */
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306 |
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307 | struct globals {
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308 | rlim_t rlim_ofile_cur;
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309 | struct rlimit rlim_ofile;
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310 | servtab_t *serv_list;
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311 | int global_queuelen;
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312 | int maxsock; /* max fd# in allsock, -1: unknown */
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313 | /* whenever maxsock grows, prev_maxsock is set to new maxsock,
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314 | * but if maxsock is set to -1, prev_maxsock is not changed */
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315 | int prev_maxsock;
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316 | unsigned max_concurrency;
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317 | smallint alarm_armed;
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318 | uid_t real_uid; /* user ID who ran us */
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319 | const char *config_filename;
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320 | parser_t *parser;
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321 | char *default_local_hostname;
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322 | #if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_CHARGEN
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323 | char *end_ring;
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324 | char *ring_pos;
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325 | char ring[128];
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326 | #endif
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327 | fd_set allsock;
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328 | /* Used in next_line(), and as scratch read buffer */
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329 | char line[256]; /* _at least_ 256, see LINE_SIZE */
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330 | } FIX_ALIASING;
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331 | #define G (*(struct globals*)bb_common_bufsiz1)
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332 | enum { LINE_SIZE = COMMON_BUFSIZE - offsetof(struct globals, line) };
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333 | #define rlim_ofile_cur (G.rlim_ofile_cur )
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334 | #define rlim_ofile (G.rlim_ofile )
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335 | #define serv_list (G.serv_list )
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336 | #define global_queuelen (G.global_queuelen)
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337 | #define maxsock (G.maxsock )
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338 | #define prev_maxsock (G.prev_maxsock )
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339 | #define max_concurrency (G.max_concurrency)
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340 | #define alarm_armed (G.alarm_armed )
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341 | #define real_uid (G.real_uid )
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342 | #define config_filename (G.config_filename)
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343 | #define parser (G.parser )
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344 | #define default_local_hostname (G.default_local_hostname)
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345 | #define first_ps_byte (G.first_ps_byte )
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346 | #define last_ps_byte (G.last_ps_byte )
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347 | #define end_ring (G.end_ring )
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348 | #define ring_pos (G.ring_pos )
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349 | #define ring (G.ring )
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350 | #define allsock (G.allsock )
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351 | #define line (G.line )
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352 | #define INIT_G() do { \
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353 | setup_common_bufsiz(); \
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354 | BUILD_BUG_ON(sizeof(G) > COMMON_BUFSIZE); \
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355 | rlim_ofile_cur = OPEN_MAX; \
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356 | global_queuelen = 128; \
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357 | config_filename = "/etc/inetd.conf"; \
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358 | } while (0)
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359 |
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360 | #if 1
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361 | # define dbg(...) ((void)0)
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362 | #else
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363 | # define dbg(...) \
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364 | do { \
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365 | int dbg_fd = open("inetd_debug.log", O_WRONLY | O_CREAT | O_APPEND, 0666); \
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366 | if (dbg_fd >= 0) { \
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367 | fdprintf(dbg_fd, "%d: ", getpid()); \
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368 | fdprintf(dbg_fd, __VA_ARGS__); \
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369 | close(dbg_fd); \
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370 | } \
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371 | } while (0)
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372 | #endif
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373 |
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374 | static void maybe_close(int fd)
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375 | {
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376 | if (fd >= 0) {
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377 | close(fd);
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378 | dbg("closed fd:%d\n", fd);
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379 | }
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380 | }
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381 |
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382 | // TODO: move to libbb?
|
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383 | static len_and_sockaddr *xzalloc_lsa(int family)
|
---|
384 | {
|
---|
385 | len_and_sockaddr *lsa;
|
---|
386 | int sz;
|
---|
387 |
|
---|
388 | sz = sizeof(struct sockaddr_in);
|
---|
389 | if (family == AF_UNIX)
|
---|
390 | sz = sizeof(struct sockaddr_un);
|
---|
391 | #if ENABLE_FEATURE_IPV6
|
---|
392 | if (family == AF_INET6)
|
---|
393 | sz = sizeof(struct sockaddr_in6);
|
---|
394 | #endif
|
---|
395 | lsa = xzalloc(LSA_LEN_SIZE + sz);
|
---|
396 | lsa->len = sz;
|
---|
397 | lsa->u.sa.sa_family = family;
|
---|
398 | return lsa;
|
---|
399 | }
|
---|
400 |
|
---|
401 | static void rearm_alarm(void)
|
---|
402 | {
|
---|
403 | if (!alarm_armed) {
|
---|
404 | alarm_armed = 1;
|
---|
405 | alarm(RETRYTIME);
|
---|
406 | }
|
---|
407 | }
|
---|
408 |
|
---|
409 | static void block_CHLD_HUP_ALRM(sigset_t *m)
|
---|
410 | {
|
---|
411 | sigemptyset(m);
|
---|
412 | sigaddset(m, SIGCHLD);
|
---|
413 | sigaddset(m, SIGHUP);
|
---|
414 | sigaddset(m, SIGALRM);
|
---|
415 | sigprocmask(SIG_BLOCK, m, m); /* old sigmask is stored in m */
|
---|
416 | }
|
---|
417 |
|
---|
418 | static void restore_sigmask(sigset_t *m)
|
---|
419 | {
|
---|
420 | sigprocmask(SIG_SETMASK, m, NULL);
|
---|
421 | }
|
---|
422 |
|
---|
423 | #if ENABLE_FEATURE_INETD_RPC
|
---|
424 | static void register_rpc(servtab_t *sep)
|
---|
425 | {
|
---|
426 | int n;
|
---|
427 | struct sockaddr_in ir_sin;
|
---|
428 | socklen_t size;
|
---|
429 |
|
---|
430 | size = sizeof(ir_sin);
|
---|
431 | if (getsockname(sep->se_fd, (struct sockaddr *) &ir_sin, &size) < 0) {
|
---|
432 | bb_perror_msg("getsockname");
|
---|
433 | return;
|
---|
434 | }
|
---|
435 |
|
---|
436 | for (n = sep->se_rpcver_lo; n <= sep->se_rpcver_hi; n++) {
|
---|
437 | pmap_unset(sep->se_rpcprog, n);
|
---|
438 | if (!pmap_set(sep->se_rpcprog, n, sep->se_proto_no, ntohs(ir_sin.sin_port)))
|
---|
439 | bb_perror_msg("%s %s: pmap_set(%u,%u,%u,%u)",
|
---|
440 | sep->se_service, sep->se_proto,
|
---|
441 | sep->se_rpcprog, n, sep->se_proto_no, ntohs(ir_sin.sin_port));
|
---|
442 | }
|
---|
443 | }
|
---|
444 |
|
---|
445 | static void unregister_rpc(servtab_t *sep)
|
---|
446 | {
|
---|
447 | int n;
|
---|
448 |
|
---|
449 | for (n = sep->se_rpcver_lo; n <= sep->se_rpcver_hi; n++) {
|
---|
450 | if (!pmap_unset(sep->se_rpcprog, n))
|
---|
451 | bb_perror_msg("pmap_unset(%u,%u)", sep->se_rpcprog, n);
|
---|
452 | }
|
---|
453 | }
|
---|
454 | #endif /* FEATURE_INETD_RPC */
|
---|
455 |
|
---|
456 | static void bump_nofile(void)
|
---|
457 | {
|
---|
458 | enum { FD_CHUNK = 32 };
|
---|
459 | struct rlimit rl;
|
---|
460 |
|
---|
461 | /* Never fails under Linux (except if you pass it bad arguments) */
|
---|
462 | getrlimit(RLIMIT_NOFILE, &rl);
|
---|
463 | rl.rlim_cur = MIN(rl.rlim_max, rl.rlim_cur + FD_CHUNK);
|
---|
464 | rl.rlim_cur = MIN(FD_SETSIZE, rl.rlim_cur + FD_CHUNK);
|
---|
465 | if (rl.rlim_cur <= rlim_ofile_cur) {
|
---|
466 | bb_error_msg("can't extend file limit, max = %d",
|
---|
467 | (int) rl.rlim_cur);
|
---|
468 | return;
|
---|
469 | }
|
---|
470 |
|
---|
471 | if (setrlimit(RLIMIT_NOFILE, &rl) < 0) {
|
---|
472 | bb_perror_msg("setrlimit");
|
---|
473 | return;
|
---|
474 | }
|
---|
475 |
|
---|
476 | rlim_ofile_cur = rl.rlim_cur;
|
---|
477 | }
|
---|
478 |
|
---|
479 | static void remove_fd_from_set(int fd)
|
---|
480 | {
|
---|
481 | if (fd >= 0) {
|
---|
482 | FD_CLR(fd, &allsock);
|
---|
483 | dbg("stopped listening on fd:%d\n", fd);
|
---|
484 | maxsock = -1;
|
---|
485 | dbg("maxsock:%d\n", maxsock);
|
---|
486 | }
|
---|
487 | }
|
---|
488 |
|
---|
489 | static void add_fd_to_set(int fd)
|
---|
490 | {
|
---|
491 | if (fd >= 0) {
|
---|
492 | FD_SET(fd, &allsock);
|
---|
493 | dbg("started listening on fd:%d\n", fd);
|
---|
494 | if (maxsock >= 0 && fd > maxsock) {
|
---|
495 | prev_maxsock = maxsock = fd;
|
---|
496 | dbg("maxsock:%d\n", maxsock);
|
---|
497 | if ((rlim_t)fd > rlim_ofile_cur - FD_MARGIN)
|
---|
498 | bump_nofile();
|
---|
499 | }
|
---|
500 | }
|
---|
501 | }
|
---|
502 |
|
---|
503 | static void recalculate_maxsock(void)
|
---|
504 | {
|
---|
505 | int fd = 0;
|
---|
506 |
|
---|
507 | /* We may have no services, in this case maxsock should still be >= 0
|
---|
508 | * (code elsewhere is not happy with maxsock == -1) */
|
---|
509 | maxsock = 0;
|
---|
510 | while (fd <= prev_maxsock) {
|
---|
511 | if (FD_ISSET(fd, &allsock))
|
---|
512 | maxsock = fd;
|
---|
513 | fd++;
|
---|
514 | }
|
---|
515 | dbg("recalculated maxsock:%d\n", maxsock);
|
---|
516 | prev_maxsock = maxsock;
|
---|
517 | if ((rlim_t)maxsock > rlim_ofile_cur - FD_MARGIN)
|
---|
518 | bump_nofile();
|
---|
519 | }
|
---|
520 |
|
---|
521 | static void prepare_socket_fd(servtab_t *sep)
|
---|
522 | {
|
---|
523 | int r, fd;
|
---|
524 |
|
---|
525 | fd = socket(sep->se_family, sep->se_socktype, 0);
|
---|
526 | if (fd < 0) {
|
---|
527 | bb_perror_msg("socket");
|
---|
528 | return;
|
---|
529 | }
|
---|
530 | setsockopt_reuseaddr(fd);
|
---|
531 |
|
---|
532 | #if ENABLE_FEATURE_INETD_RPC
|
---|
533 | if (is_rpc_service(sep)) {
|
---|
534 | struct passwd *pwd;
|
---|
535 |
|
---|
536 | /* zero out the port for all RPC services; let bind()
|
---|
537 | * find one. */
|
---|
538 | set_nport(&sep->se_lsa->u.sa, 0);
|
---|
539 |
|
---|
540 | /* for RPC services, attempt to use a reserved port
|
---|
541 | * if they are going to be running as root. */
|
---|
542 | if (real_uid == 0 && sep->se_family == AF_INET
|
---|
543 | && (pwd = getpwnam(sep->se_user)) != NULL
|
---|
544 | && pwd->pw_uid == 0
|
---|
545 | ) {
|
---|
546 | r = bindresvport(fd, &sep->se_lsa->u.sin);
|
---|
547 | } else {
|
---|
548 | r = bind(fd, &sep->se_lsa->u.sa, sep->se_lsa->len);
|
---|
549 | }
|
---|
550 | if (r == 0) {
|
---|
551 | int saveerrno = errno;
|
---|
552 | /* update lsa with port# */
|
---|
553 | getsockname(fd, &sep->se_lsa->u.sa, &sep->se_lsa->len);
|
---|
554 | errno = saveerrno;
|
---|
555 | }
|
---|
556 | } else
|
---|
557 | #endif
|
---|
558 | {
|
---|
559 | if (sep->se_family == AF_UNIX) {
|
---|
560 | struct sockaddr_un *sun;
|
---|
561 | sun = (struct sockaddr_un*)&(sep->se_lsa->u.sa);
|
---|
562 | unlink(sun->sun_path);
|
---|
563 | }
|
---|
564 | r = bind(fd, &sep->se_lsa->u.sa, sep->se_lsa->len);
|
---|
565 | }
|
---|
566 | if (r < 0) {
|
---|
567 | bb_perror_msg("%s/%s: bind",
|
---|
568 | sep->se_service, sep->se_proto);
|
---|
569 | close(fd);
|
---|
570 | rearm_alarm();
|
---|
571 | return;
|
---|
572 | }
|
---|
573 |
|
---|
574 | if (sep->se_socktype == SOCK_STREAM) {
|
---|
575 | listen(fd, global_queuelen);
|
---|
576 | dbg("new sep->se_fd:%d (stream)\n", fd);
|
---|
577 | } else {
|
---|
578 | dbg("new sep->se_fd:%d (!stream)\n", fd);
|
---|
579 | }
|
---|
580 |
|
---|
581 | add_fd_to_set(fd);
|
---|
582 | sep->se_fd = fd;
|
---|
583 | }
|
---|
584 |
|
---|
585 | static int reopen_config_file(void)
|
---|
586 | {
|
---|
587 | free(default_local_hostname);
|
---|
588 | default_local_hostname = xstrdup("*");
|
---|
589 | if (parser != NULL)
|
---|
590 | config_close(parser);
|
---|
591 | parser = config_open(config_filename);
|
---|
592 | return (parser != NULL);
|
---|
593 | }
|
---|
594 |
|
---|
595 | static void close_config_file(void)
|
---|
596 | {
|
---|
597 | if (parser) {
|
---|
598 | config_close(parser);
|
---|
599 | parser = NULL;
|
---|
600 | }
|
---|
601 | }
|
---|
602 |
|
---|
603 | static void free_servtab_strings(servtab_t *cp)
|
---|
604 | {
|
---|
605 | int i;
|
---|
606 |
|
---|
607 | free(cp->se_local_hostname);
|
---|
608 | free(cp->se_service);
|
---|
609 | free(cp->se_proto);
|
---|
610 | free(cp->se_user);
|
---|
611 | free(cp->se_group);
|
---|
612 | free(cp->se_lsa); /* not a string in fact */
|
---|
613 | free(cp->se_program);
|
---|
614 | for (i = 0; i < MAXARGV; i++)
|
---|
615 | free(cp->se_argv[i]);
|
---|
616 | }
|
---|
617 |
|
---|
618 | static servtab_t *new_servtab(void)
|
---|
619 | {
|
---|
620 | servtab_t *newtab = xzalloc(sizeof(servtab_t));
|
---|
621 | newtab->se_fd = -1; /* paranoia */
|
---|
622 | return newtab;
|
---|
623 | }
|
---|
624 |
|
---|
625 | static servtab_t *dup_servtab(servtab_t *sep)
|
---|
626 | {
|
---|
627 | servtab_t *newtab;
|
---|
628 | int argc;
|
---|
629 |
|
---|
630 | newtab = new_servtab();
|
---|
631 | *newtab = *sep; /* struct copy */
|
---|
632 | /* deep-copying strings */
|
---|
633 | newtab->se_service = xstrdup(newtab->se_service);
|
---|
634 | newtab->se_proto = xstrdup(newtab->se_proto);
|
---|
635 | newtab->se_user = xstrdup(newtab->se_user);
|
---|
636 | newtab->se_group = xstrdup(newtab->se_group);
|
---|
637 | newtab->se_program = xstrdup(newtab->se_program);
|
---|
638 | for (argc = 0; argc <= MAXARGV; argc++)
|
---|
639 | newtab->se_argv[argc] = xstrdup(newtab->se_argv[argc]);
|
---|
640 | /* NB: se_fd, se_hostaddr and se_next are always
|
---|
641 | * overwrittend by callers, so we don't bother resetting them
|
---|
642 | * to NULL/0/-1 etc */
|
---|
643 |
|
---|
644 | return newtab;
|
---|
645 | }
|
---|
646 |
|
---|
647 | /* gcc generates much more code if this is inlined */
|
---|
648 | static NOINLINE servtab_t *parse_one_line(void)
|
---|
649 | {
|
---|
650 | int argc;
|
---|
651 | char *token[6+MAXARGV];
|
---|
652 | char *p, *arg;
|
---|
653 | char *hostdelim;
|
---|
654 | servtab_t *sep;
|
---|
655 | servtab_t *nsep;
|
---|
656 | new:
|
---|
657 | sep = new_servtab();
|
---|
658 | more:
|
---|
659 | argc = config_read(parser, token, 6+MAXARGV, 1, "# \t", PARSE_NORMAL);
|
---|
660 | if (!argc) {
|
---|
661 | free(sep);
|
---|
662 | return NULL;
|
---|
663 | }
|
---|
664 |
|
---|
665 | /* [host:]service socktype proto wait user[:group] prog [args] */
|
---|
666 | /* Check for "host:...." line */
|
---|
667 | arg = token[0];
|
---|
668 | hostdelim = strrchr(arg, ':');
|
---|
669 | if (hostdelim) {
|
---|
670 | *hostdelim = '\0';
|
---|
671 | sep->se_local_hostname = xstrdup(arg);
|
---|
672 | arg = hostdelim + 1;
|
---|
673 | if (*arg == '\0' && argc == 1) {
|
---|
674 | /* Line has just "host:", change the
|
---|
675 | * default host for the following lines. */
|
---|
676 | free(default_local_hostname);
|
---|
677 | default_local_hostname = sep->se_local_hostname;
|
---|
678 | /*sep->se_local_hostname = NULL; - redundant */
|
---|
679 | /* (we'll overwrite this field anyway) */
|
---|
680 | goto more;
|
---|
681 | }
|
---|
682 | } else
|
---|
683 | sep->se_local_hostname = xstrdup(default_local_hostname);
|
---|
684 |
|
---|
685 | /* service socktype proto wait user[:group] prog [args] */
|
---|
686 | sep->se_service = xstrdup(arg);
|
---|
687 |
|
---|
688 | /* socktype proto wait user[:group] prog [args] */
|
---|
689 | if (argc < 6) {
|
---|
690 | parse_err:
|
---|
691 | bb_error_msg("parse error on line %u, line is ignored",
|
---|
692 | parser->lineno);
|
---|
693 | /* Just "goto more" can make sep to carry over e.g.
|
---|
694 | * "rpc"-ness (by having se_rpcver_lo != 0).
|
---|
695 | * We will be more paranoid: */
|
---|
696 | free_servtab_strings(sep);
|
---|
697 | free(sep);
|
---|
698 | goto new;
|
---|
699 | }
|
---|
700 |
|
---|
701 | {
|
---|
702 | static const int8_t SOCK_xxx[] ALIGN1 = {
|
---|
703 | -1,
|
---|
704 | SOCK_STREAM, SOCK_DGRAM, SOCK_RDM,
|
---|
705 | SOCK_SEQPACKET, SOCK_RAW
|
---|
706 | };
|
---|
707 | sep->se_socktype = SOCK_xxx[1 + index_in_strings(
|
---|
708 | "stream""\0" "dgram""\0" "rdm""\0"
|
---|
709 | "seqpacket""\0" "raw""\0"
|
---|
710 | , token[1])];
|
---|
711 | }
|
---|
712 |
|
---|
713 | /* {unix,[rpc/]{tcp,udp}[6]} wait user[:group] prog [args] */
|
---|
714 | sep->se_proto = arg = xstrdup(token[2]);
|
---|
715 | if (strcmp(arg, "unix") == 0) {
|
---|
716 | sep->se_family = AF_UNIX;
|
---|
717 | } else {
|
---|
718 | char *six;
|
---|
719 | sep->se_family = AF_INET;
|
---|
720 | six = last_char_is(arg, '6');
|
---|
721 | if (six) {
|
---|
722 | #if ENABLE_FEATURE_IPV6
|
---|
723 | *six = '\0';
|
---|
724 | sep->se_family = AF_INET6;
|
---|
725 | #else
|
---|
726 | bb_error_msg("%s: no support for IPv6", sep->se_proto);
|
---|
727 | goto parse_err;
|
---|
728 | #endif
|
---|
729 | }
|
---|
730 | if (is_prefixed_with(arg, "rpc/")) {
|
---|
731 | #if ENABLE_FEATURE_INETD_RPC
|
---|
732 | unsigned n;
|
---|
733 | arg += 4;
|
---|
734 | p = strchr(sep->se_service, '/');
|
---|
735 | if (p == NULL) {
|
---|
736 | bb_error_msg("no rpc version: '%s'", sep->se_service);
|
---|
737 | goto parse_err;
|
---|
738 | }
|
---|
739 | *p++ = '\0';
|
---|
740 | n = bb_strtou(p, &p, 10);
|
---|
741 | if (n > INT_MAX) {
|
---|
742 | bad_ver_spec:
|
---|
743 | bb_error_msg("bad rpc version");
|
---|
744 | goto parse_err;
|
---|
745 | }
|
---|
746 | sep->se_rpcver_lo = sep->se_rpcver_hi = n;
|
---|
747 | if (*p == '-') {
|
---|
748 | p++;
|
---|
749 | n = bb_strtou(p, &p, 10);
|
---|
750 | if (n > INT_MAX || (int)n < sep->se_rpcver_lo)
|
---|
751 | goto bad_ver_spec;
|
---|
752 | sep->se_rpcver_hi = n;
|
---|
753 | }
|
---|
754 | if (*p != '\0')
|
---|
755 | goto bad_ver_spec;
|
---|
756 | #else
|
---|
757 | bb_error_msg("no support for rpc services");
|
---|
758 | goto parse_err;
|
---|
759 | #endif
|
---|
760 | }
|
---|
761 | /* we don't really need getprotobyname()! */
|
---|
762 | if (strcmp(arg, "tcp") == 0)
|
---|
763 | sep->se_proto_no = IPPROTO_TCP; /* = 6 */
|
---|
764 | if (strcmp(arg, "udp") == 0)
|
---|
765 | sep->se_proto_no = IPPROTO_UDP; /* = 17 */
|
---|
766 | if (six)
|
---|
767 | *six = '6';
|
---|
768 | if (!sep->se_proto_no) /* not tcp/udp?? */
|
---|
769 | goto parse_err;
|
---|
770 | }
|
---|
771 |
|
---|
772 | /* [no]wait[.max] user[:group] prog [args] */
|
---|
773 | arg = token[3];
|
---|
774 | sep->se_max = max_concurrency;
|
---|
775 | p = strchr(arg, '.');
|
---|
776 | if (p) {
|
---|
777 | *p++ = '\0';
|
---|
778 | sep->se_max = bb_strtou(p, NULL, 10);
|
---|
779 | if (errno)
|
---|
780 | goto parse_err;
|
---|
781 | }
|
---|
782 | sep->se_wait = (arg[0] != 'n' || arg[1] != 'o');
|
---|
783 | if (!sep->se_wait) /* "no" seen */
|
---|
784 | arg += 2;
|
---|
785 | if (strcmp(arg, "wait") != 0)
|
---|
786 | goto parse_err;
|
---|
787 |
|
---|
788 | /* user[:group] prog [args] */
|
---|
789 | sep->se_user = xstrdup(token[4]);
|
---|
790 | arg = strchr(sep->se_user, '.');
|
---|
791 | if (arg == NULL)
|
---|
792 | arg = strchr(sep->se_user, ':');
|
---|
793 | if (arg) {
|
---|
794 | *arg++ = '\0';
|
---|
795 | sep->se_group = xstrdup(arg);
|
---|
796 | }
|
---|
797 |
|
---|
798 | /* prog [args] */
|
---|
799 | sep->se_program = xstrdup(token[5]);
|
---|
800 | #ifdef INETD_BUILTINS_ENABLED
|
---|
801 | if (strcmp(sep->se_program, "internal") == 0
|
---|
802 | && strlen(sep->se_service) <= 7
|
---|
803 | && (sep->se_socktype == SOCK_STREAM
|
---|
804 | || sep->se_socktype == SOCK_DGRAM)
|
---|
805 | ) {
|
---|
806 | unsigned i;
|
---|
807 | for (i = 0; i < ARRAY_SIZE(builtins); i++)
|
---|
808 | if (strncmp(builtins[i].bi_service7, sep->se_service, 7) == 0)
|
---|
809 | goto found_bi;
|
---|
810 | bb_error_msg("unknown internal service %s", sep->se_service);
|
---|
811 | goto parse_err;
|
---|
812 | found_bi:
|
---|
813 | sep->se_builtin = &builtins[i];
|
---|
814 | /* stream builtins must be "nowait", dgram must be "wait" */
|
---|
815 | if (sep->se_wait != (sep->se_socktype == SOCK_DGRAM))
|
---|
816 | goto parse_err;
|
---|
817 | }
|
---|
818 | #endif
|
---|
819 | argc = 0;
|
---|
820 | while (argc < MAXARGV && (arg = token[6+argc]) != NULL)
|
---|
821 | sep->se_argv[argc++] = xstrdup(arg);
|
---|
822 | /* Some inetd.conf files have no argv's, not even argv[0].
|
---|
823 | * Fix them up.
|
---|
824 | * (Technically, programs can be execed with argv[0] = NULL,
|
---|
825 | * but many programs do not like that at all) */
|
---|
826 | if (argc == 0)
|
---|
827 | sep->se_argv[0] = xstrdup(sep->se_program);
|
---|
828 |
|
---|
829 | /* catch mixups. "<service> stream udp ..." == wtf */
|
---|
830 | if (sep->se_socktype == SOCK_STREAM) {
|
---|
831 | if (sep->se_proto_no == IPPROTO_UDP)
|
---|
832 | goto parse_err;
|
---|
833 | }
|
---|
834 | if (sep->se_socktype == SOCK_DGRAM) {
|
---|
835 | if (sep->se_proto_no == IPPROTO_TCP)
|
---|
836 | goto parse_err;
|
---|
837 | }
|
---|
838 |
|
---|
839 | //bb_error_msg(
|
---|
840 | // "ENTRY[%s][%s][%s][%d][%d][%d][%d][%d][%s][%s][%s]",
|
---|
841 | // sep->se_local_hostname, sep->se_service, sep->se_proto, sep->se_wait, sep->se_proto_no,
|
---|
842 | // sep->se_max, sep->se_count, sep->se_time, sep->se_user, sep->se_group, sep->se_program);
|
---|
843 |
|
---|
844 | /* check if the hostname specifier is a comma separated list
|
---|
845 | * of hostnames. we'll make new entries for each address. */
|
---|
846 | while ((hostdelim = strrchr(sep->se_local_hostname, ',')) != NULL) {
|
---|
847 | nsep = dup_servtab(sep);
|
---|
848 | /* NUL terminate the hostname field of the existing entry,
|
---|
849 | * and make a dup for the new entry. */
|
---|
850 | *hostdelim++ = '\0';
|
---|
851 | nsep->se_local_hostname = xstrdup(hostdelim);
|
---|
852 | nsep->se_next = sep->se_next;
|
---|
853 | sep->se_next = nsep;
|
---|
854 | }
|
---|
855 |
|
---|
856 | /* was doing it here: */
|
---|
857 | /* DNS resolution, create copies for each IP address */
|
---|
858 | /* IPv6-ization destroyed it :( */
|
---|
859 |
|
---|
860 | return sep;
|
---|
861 | }
|
---|
862 |
|
---|
863 | static servtab_t *insert_in_servlist(servtab_t *cp)
|
---|
864 | {
|
---|
865 | servtab_t *sep;
|
---|
866 | sigset_t omask;
|
---|
867 |
|
---|
868 | sep = new_servtab();
|
---|
869 | *sep = *cp; /* struct copy */
|
---|
870 | sep->se_fd = -1;
|
---|
871 | #if ENABLE_FEATURE_INETD_RPC
|
---|
872 | sep->se_rpcprog = -1;
|
---|
873 | #endif
|
---|
874 | block_CHLD_HUP_ALRM(&omask);
|
---|
875 | sep->se_next = serv_list;
|
---|
876 | serv_list = sep;
|
---|
877 | restore_sigmask(&omask);
|
---|
878 | return sep;
|
---|
879 | }
|
---|
880 |
|
---|
881 | static int same_serv_addr_proto(servtab_t *old, servtab_t *new)
|
---|
882 | {
|
---|
883 | if (strcmp(old->se_local_hostname, new->se_local_hostname) != 0)
|
---|
884 | return 0;
|
---|
885 | if (strcmp(old->se_service, new->se_service) != 0)
|
---|
886 | return 0;
|
---|
887 | if (strcmp(old->se_proto, new->se_proto) != 0)
|
---|
888 | return 0;
|
---|
889 | return 1;
|
---|
890 | }
|
---|
891 |
|
---|
892 | static void reread_config_file(int sig UNUSED_PARAM)
|
---|
893 | {
|
---|
894 | servtab_t *sep, *cp, **sepp;
|
---|
895 | len_and_sockaddr *lsa;
|
---|
896 | sigset_t omask;
|
---|
897 | unsigned n;
|
---|
898 | uint16_t port;
|
---|
899 | int save_errno = errno;
|
---|
900 |
|
---|
901 | if (!reopen_config_file())
|
---|
902 | goto ret;
|
---|
903 | for (sep = serv_list; sep; sep = sep->se_next)
|
---|
904 | sep->se_checked = 0;
|
---|
905 |
|
---|
906 | goto first_line;
|
---|
907 | while (1) {
|
---|
908 | if (cp == NULL) {
|
---|
909 | first_line:
|
---|
910 | cp = parse_one_line();
|
---|
911 | if (cp == NULL)
|
---|
912 | break;
|
---|
913 | }
|
---|
914 | for (sep = serv_list; sep; sep = sep->se_next)
|
---|
915 | if (same_serv_addr_proto(sep, cp))
|
---|
916 | goto equal_servtab;
|
---|
917 | /* not an "equal" servtab */
|
---|
918 | sep = insert_in_servlist(cp);
|
---|
919 | goto after_check;
|
---|
920 | equal_servtab:
|
---|
921 | {
|
---|
922 | int i;
|
---|
923 |
|
---|
924 | block_CHLD_HUP_ALRM(&omask);
|
---|
925 | #if ENABLE_FEATURE_INETD_RPC
|
---|
926 | if (is_rpc_service(sep))
|
---|
927 | unregister_rpc(sep);
|
---|
928 | sep->se_rpcver_lo = cp->se_rpcver_lo;
|
---|
929 | sep->se_rpcver_hi = cp->se_rpcver_hi;
|
---|
930 | #endif
|
---|
931 | if (cp->se_wait == 0) {
|
---|
932 | /* New config says "nowait". If old one
|
---|
933 | * was "wait", we currently may be waiting
|
---|
934 | * for a child (and not accepting connects).
|
---|
935 | * Stop waiting, start listening again.
|
---|
936 | * (if it's not true, this op is harmless) */
|
---|
937 | add_fd_to_set(sep->se_fd);
|
---|
938 | }
|
---|
939 | sep->se_wait = cp->se_wait;
|
---|
940 | sep->se_max = cp->se_max;
|
---|
941 | /* string fields need more love - we don't want to leak them */
|
---|
942 | #define SWAP(type, a, b) do { type c = (type)a; a = (type)b; b = (type)c; } while (0)
|
---|
943 | SWAP(char*, sep->se_user, cp->se_user);
|
---|
944 | SWAP(char*, sep->se_group, cp->se_group);
|
---|
945 | SWAP(char*, sep->se_program, cp->se_program);
|
---|
946 | for (i = 0; i < MAXARGV; i++)
|
---|
947 | SWAP(char*, sep->se_argv[i], cp->se_argv[i]);
|
---|
948 | #undef SWAP
|
---|
949 | restore_sigmask(&omask);
|
---|
950 | free_servtab_strings(cp);
|
---|
951 | }
|
---|
952 | after_check:
|
---|
953 | /* cp->string_fields are consumed by insert_in_servlist()
|
---|
954 | * or freed at this point, cp itself is not yet freed. */
|
---|
955 | sep->se_checked = 1;
|
---|
956 |
|
---|
957 | /* create new len_and_sockaddr */
|
---|
958 | switch (sep->se_family) {
|
---|
959 | struct sockaddr_un *sun;
|
---|
960 | case AF_UNIX:
|
---|
961 | lsa = xzalloc_lsa(AF_UNIX);
|
---|
962 | sun = (struct sockaddr_un*)&lsa->u.sa;
|
---|
963 | safe_strncpy(sun->sun_path, sep->se_service, sizeof(sun->sun_path));
|
---|
964 | break;
|
---|
965 |
|
---|
966 | default: /* case AF_INET, case AF_INET6 */
|
---|
967 | n = bb_strtou(sep->se_service, NULL, 10);
|
---|
968 | #if ENABLE_FEATURE_INETD_RPC
|
---|
969 | if (is_rpc_service(sep)) {
|
---|
970 | sep->se_rpcprog = n;
|
---|
971 | if (errno) { /* se_service is not numeric */
|
---|
972 | struct rpcent *rp = getrpcbyname(sep->se_service);
|
---|
973 | if (rp == NULL) {
|
---|
974 | bb_error_msg("%s: unknown rpc service", sep->se_service);
|
---|
975 | goto next_cp;
|
---|
976 | }
|
---|
977 | sep->se_rpcprog = rp->r_number;
|
---|
978 | }
|
---|
979 | if (sep->se_fd == -1)
|
---|
980 | prepare_socket_fd(sep);
|
---|
981 | if (sep->se_fd != -1)
|
---|
982 | register_rpc(sep);
|
---|
983 | goto next_cp;
|
---|
984 | }
|
---|
985 | #endif
|
---|
986 | /* what port to listen on? */
|
---|
987 | port = htons(n);
|
---|
988 | if (errno || n > 0xffff) { /* se_service is not numeric */
|
---|
989 | char protoname[4];
|
---|
990 | struct servent *sp;
|
---|
991 | /* can result only in "tcp" or "udp": */
|
---|
992 | safe_strncpy(protoname, sep->se_proto, 4);
|
---|
993 | sp = getservbyname(sep->se_service, protoname);
|
---|
994 | if (sp == NULL) {
|
---|
995 | bb_error_msg("%s/%s: unknown service",
|
---|
996 | sep->se_service, sep->se_proto);
|
---|
997 | goto next_cp;
|
---|
998 | }
|
---|
999 | port = sp->s_port;
|
---|
1000 | }
|
---|
1001 | if (LONE_CHAR(sep->se_local_hostname, '*')) {
|
---|
1002 | lsa = xzalloc_lsa(sep->se_family);
|
---|
1003 | set_nport(&lsa->u.sa, port);
|
---|
1004 | } else {
|
---|
1005 | lsa = host_and_af2sockaddr(sep->se_local_hostname,
|
---|
1006 | ntohs(port), sep->se_family);
|
---|
1007 | if (!lsa) {
|
---|
1008 | bb_error_msg("%s/%s: unknown host '%s'",
|
---|
1009 | sep->se_service, sep->se_proto,
|
---|
1010 | sep->se_local_hostname);
|
---|
1011 | goto next_cp;
|
---|
1012 | }
|
---|
1013 | }
|
---|
1014 | break;
|
---|
1015 | } /* end of "switch (sep->se_family)" */
|
---|
1016 |
|
---|
1017 | /* did lsa change? Then close/open */
|
---|
1018 | if (sep->se_lsa == NULL
|
---|
1019 | || lsa->len != sep->se_lsa->len
|
---|
1020 | || memcmp(&lsa->u.sa, &sep->se_lsa->u.sa, lsa->len) != 0
|
---|
1021 | ) {
|
---|
1022 | remove_fd_from_set(sep->se_fd);
|
---|
1023 | maybe_close(sep->se_fd);
|
---|
1024 | free(sep->se_lsa);
|
---|
1025 | sep->se_lsa = lsa;
|
---|
1026 | sep->se_fd = -1;
|
---|
1027 | } else {
|
---|
1028 | free(lsa);
|
---|
1029 | }
|
---|
1030 | if (sep->se_fd == -1)
|
---|
1031 | prepare_socket_fd(sep);
|
---|
1032 | next_cp:
|
---|
1033 | sep = cp->se_next;
|
---|
1034 | free(cp);
|
---|
1035 | cp = sep;
|
---|
1036 | } /* end of "while (1) parse lines" */
|
---|
1037 | close_config_file();
|
---|
1038 |
|
---|
1039 | /* Purge anything not looked at above - these are stale entries,
|
---|
1040 | * new config file doesnt have them. */
|
---|
1041 | block_CHLD_HUP_ALRM(&omask);
|
---|
1042 | sepp = &serv_list;
|
---|
1043 | while ((sep = *sepp) != NULL) {
|
---|
1044 | if (sep->se_checked) {
|
---|
1045 | sepp = &sep->se_next;
|
---|
1046 | continue;
|
---|
1047 | }
|
---|
1048 | *sepp = sep->se_next;
|
---|
1049 | remove_fd_from_set(sep->se_fd);
|
---|
1050 | maybe_close(sep->se_fd);
|
---|
1051 | #if ENABLE_FEATURE_INETD_RPC
|
---|
1052 | if (is_rpc_service(sep))
|
---|
1053 | unregister_rpc(sep);
|
---|
1054 | #endif
|
---|
1055 | if (sep->se_family == AF_UNIX)
|
---|
1056 | unlink(sep->se_service);
|
---|
1057 | free_servtab_strings(sep);
|
---|
1058 | free(sep);
|
---|
1059 | }
|
---|
1060 | restore_sigmask(&omask);
|
---|
1061 | ret:
|
---|
1062 | errno = save_errno;
|
---|
1063 | }
|
---|
1064 |
|
---|
1065 | static void reap_child(int sig UNUSED_PARAM)
|
---|
1066 | {
|
---|
1067 | pid_t pid;
|
---|
1068 | int status;
|
---|
1069 | servtab_t *sep;
|
---|
1070 | int save_errno = errno;
|
---|
1071 |
|
---|
1072 | for (;;) {
|
---|
1073 | pid = wait_any_nohang(&status);
|
---|
1074 | if (pid <= 0)
|
---|
1075 | break;
|
---|
1076 | for (sep = serv_list; sep; sep = sep->se_next) {
|
---|
1077 | if (sep->se_wait != pid)
|
---|
1078 | continue;
|
---|
1079 | /* One of our "wait" services */
|
---|
1080 | if (WIFEXITED(status) && WEXITSTATUS(status))
|
---|
1081 | bb_error_msg("%s: exit status %u",
|
---|
1082 | sep->se_program, WEXITSTATUS(status));
|
---|
1083 | else if (WIFSIGNALED(status))
|
---|
1084 | bb_error_msg("%s: exit signal %u",
|
---|
1085 | sep->se_program, WTERMSIG(status));
|
---|
1086 | sep->se_wait = 1;
|
---|
1087 | add_fd_to_set(sep->se_fd);
|
---|
1088 | break;
|
---|
1089 | }
|
---|
1090 | }
|
---|
1091 | errno = save_errno;
|
---|
1092 | }
|
---|
1093 |
|
---|
1094 | static void retry_network_setup(int sig UNUSED_PARAM)
|
---|
1095 | {
|
---|
1096 | int save_errno = errno;
|
---|
1097 | servtab_t *sep;
|
---|
1098 |
|
---|
1099 | alarm_armed = 0;
|
---|
1100 | for (sep = serv_list; sep; sep = sep->se_next) {
|
---|
1101 | if (sep->se_fd == -1) {
|
---|
1102 | prepare_socket_fd(sep);
|
---|
1103 | #if ENABLE_FEATURE_INETD_RPC
|
---|
1104 | if (sep->se_fd != -1 && is_rpc_service(sep))
|
---|
1105 | register_rpc(sep);
|
---|
1106 | #endif
|
---|
1107 | }
|
---|
1108 | }
|
---|
1109 | errno = save_errno;
|
---|
1110 | }
|
---|
1111 |
|
---|
1112 | static void clean_up_and_exit(int sig UNUSED_PARAM)
|
---|
1113 | {
|
---|
1114 | servtab_t *sep;
|
---|
1115 |
|
---|
1116 | /* XXX signal race walking sep list */
|
---|
1117 | for (sep = serv_list; sep; sep = sep->se_next) {
|
---|
1118 | if (sep->se_fd == -1)
|
---|
1119 | continue;
|
---|
1120 |
|
---|
1121 | switch (sep->se_family) {
|
---|
1122 | case AF_UNIX:
|
---|
1123 | unlink(sep->se_service);
|
---|
1124 | break;
|
---|
1125 | default: /* case AF_INET, AF_INET6 */
|
---|
1126 | #if ENABLE_FEATURE_INETD_RPC
|
---|
1127 | if (sep->se_wait == 1 && is_rpc_service(sep))
|
---|
1128 | unregister_rpc(sep); /* XXX signal race */
|
---|
1129 | #endif
|
---|
1130 | break;
|
---|
1131 | }
|
---|
1132 | if (ENABLE_FEATURE_CLEAN_UP)
|
---|
1133 | close(sep->se_fd);
|
---|
1134 | }
|
---|
1135 | remove_pidfile(CONFIG_PID_FILE_PATH "/inetd.pid");
|
---|
1136 | exit(EXIT_SUCCESS);
|
---|
1137 | }
|
---|
1138 |
|
---|
1139 | int inetd_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
|
---|
1140 | int inetd_main(int argc UNUSED_PARAM, char **argv)
|
---|
1141 | {
|
---|
1142 | struct sigaction sa, saved_pipe_handler;
|
---|
1143 | servtab_t *sep, *sep2;
|
---|
1144 | struct passwd *pwd;
|
---|
1145 | struct group *grp = grp; /* for compiler */
|
---|
1146 | int opt;
|
---|
1147 | pid_t pid;
|
---|
1148 | sigset_t omask;
|
---|
1149 |
|
---|
1150 | INIT_G();
|
---|
1151 |
|
---|
1152 | real_uid = getuid();
|
---|
1153 | if (real_uid != 0) /* run by non-root user */
|
---|
1154 | config_filename = NULL;
|
---|
1155 |
|
---|
1156 | opt_complementary = "R+:q+"; /* -q N, -R N */
|
---|
1157 | opt = getopt32(argv, "R:feq:", &max_concurrency, &global_queuelen);
|
---|
1158 | argv += optind;
|
---|
1159 | //argc -= optind;
|
---|
1160 | if (argv[0])
|
---|
1161 | config_filename = argv[0];
|
---|
1162 | if (config_filename == NULL)
|
---|
1163 | bb_error_msg_and_die("non-root must specify config file");
|
---|
1164 | if (!(opt & 2))
|
---|
1165 | bb_daemonize_or_rexec(0, argv - optind);
|
---|
1166 | else
|
---|
1167 | bb_sanitize_stdio();
|
---|
1168 | if (!(opt & 4)) {
|
---|
1169 | /* LOG_NDELAY: connect to syslog daemon NOW.
|
---|
1170 | * Otherwise, we may open syslog socket
|
---|
1171 | * in vforked child, making opened fds and syslog()
|
---|
1172 | * internal state inconsistent.
|
---|
1173 | * This was observed to leak file descriptors. */
|
---|
1174 | openlog(applet_name, LOG_PID | LOG_NDELAY, LOG_DAEMON);
|
---|
1175 | logmode = LOGMODE_SYSLOG;
|
---|
1176 | }
|
---|
1177 |
|
---|
1178 | if (real_uid == 0) {
|
---|
1179 | /* run by root, ensure groups vector gets trashed */
|
---|
1180 | gid_t gid = getgid();
|
---|
1181 | setgroups(1, &gid);
|
---|
1182 | }
|
---|
1183 |
|
---|
1184 | write_pidfile(CONFIG_PID_FILE_PATH "/inetd.pid");
|
---|
1185 |
|
---|
1186 | /* never fails under Linux (except if you pass it bad arguments) */
|
---|
1187 | getrlimit(RLIMIT_NOFILE, &rlim_ofile);
|
---|
1188 | rlim_ofile_cur = rlim_ofile.rlim_cur;
|
---|
1189 | if (rlim_ofile_cur == RLIM_INFINITY) /* ! */
|
---|
1190 | rlim_ofile_cur = OPEN_MAX;
|
---|
1191 |
|
---|
1192 | memset(&sa, 0, sizeof(sa));
|
---|
1193 | /*sigemptyset(&sa.sa_mask); - memset did it */
|
---|
1194 | sigaddset(&sa.sa_mask, SIGALRM);
|
---|
1195 | sigaddset(&sa.sa_mask, SIGCHLD);
|
---|
1196 | sigaddset(&sa.sa_mask, SIGHUP);
|
---|
1197 | //FIXME: explain why no SA_RESTART
|
---|
1198 | //FIXME: retry_network_setup is unsafe to run in signal handler (many reasons)!
|
---|
1199 | sa.sa_handler = retry_network_setup;
|
---|
1200 | sigaction_set(SIGALRM, &sa);
|
---|
1201 | //FIXME: reread_config_file is unsafe to run in signal handler(many reasons)!
|
---|
1202 | sa.sa_handler = reread_config_file;
|
---|
1203 | sigaction_set(SIGHUP, &sa);
|
---|
1204 | //FIXME: reap_child is unsafe to run in signal handler (uses stdio)!
|
---|
1205 | sa.sa_handler = reap_child;
|
---|
1206 | sigaction_set(SIGCHLD, &sa);
|
---|
1207 | //FIXME: clean_up_and_exit is unsafe to run in signal handler (uses stdio)!
|
---|
1208 | sa.sa_handler = clean_up_and_exit;
|
---|
1209 | sigaction_set(SIGTERM, &sa);
|
---|
1210 | sa.sa_handler = clean_up_and_exit;
|
---|
1211 | sigaction_set(SIGINT, &sa);
|
---|
1212 | sa.sa_handler = SIG_IGN;
|
---|
1213 | sigaction(SIGPIPE, &sa, &saved_pipe_handler);
|
---|
1214 |
|
---|
1215 | reread_config_file(SIGHUP); /* load config from file */
|
---|
1216 |
|
---|
1217 | for (;;) {
|
---|
1218 | int ready_fd_cnt;
|
---|
1219 | int ctrl, accepted_fd, new_udp_fd;
|
---|
1220 | fd_set readable;
|
---|
1221 |
|
---|
1222 | if (maxsock < 0)
|
---|
1223 | recalculate_maxsock();
|
---|
1224 |
|
---|
1225 | readable = allsock; /* struct copy */
|
---|
1226 | /* if there are no fds to wait on, we will block
|
---|
1227 | * until signal wakes us up (maxsock == 0, but readable
|
---|
1228 | * never contains fds 0 and 1...) */
|
---|
1229 | ready_fd_cnt = select(maxsock + 1, &readable, NULL, NULL, NULL);
|
---|
1230 | if (ready_fd_cnt < 0) {
|
---|
1231 | if (errno != EINTR) {
|
---|
1232 | bb_perror_msg("select");
|
---|
1233 | sleep(1);
|
---|
1234 | }
|
---|
1235 | continue;
|
---|
1236 | }
|
---|
1237 | dbg("ready_fd_cnt:%d\n", ready_fd_cnt);
|
---|
1238 |
|
---|
1239 | for (sep = serv_list; ready_fd_cnt && sep; sep = sep->se_next) {
|
---|
1240 | if (sep->se_fd == -1 || !FD_ISSET(sep->se_fd, &readable))
|
---|
1241 | continue;
|
---|
1242 |
|
---|
1243 | dbg("ready fd:%d\n", sep->se_fd);
|
---|
1244 | ready_fd_cnt--;
|
---|
1245 | ctrl = sep->se_fd;
|
---|
1246 | accepted_fd = -1;
|
---|
1247 | new_udp_fd = -1;
|
---|
1248 | if (!sep->se_wait) {
|
---|
1249 | if (sep->se_socktype == SOCK_STREAM) {
|
---|
1250 | ctrl = accepted_fd = accept(sep->se_fd, NULL, NULL);
|
---|
1251 | dbg("accepted_fd:%d\n", accepted_fd);
|
---|
1252 | if (ctrl < 0) {
|
---|
1253 | if (errno != EINTR)
|
---|
1254 | bb_perror_msg("accept (for %s)", sep->se_service);
|
---|
1255 | continue;
|
---|
1256 | }
|
---|
1257 | }
|
---|
1258 | /* "nowait" udp */
|
---|
1259 | if (sep->se_socktype == SOCK_DGRAM
|
---|
1260 | && sep->se_family != AF_UNIX
|
---|
1261 | ) {
|
---|
1262 | /* How udp "nowait" works:
|
---|
1263 | * child peeks at (received and buffered by kernel) UDP packet,
|
---|
1264 | * performs connect() on the socket so that it is linked only
|
---|
1265 | * to this peer. But this also affects parent, because descriptors
|
---|
1266 | * are shared after fork() a-la dup(). When parent performs
|
---|
1267 | * select(), it will see this descriptor connected to the peer (!)
|
---|
1268 | * and still readable, will act on it and mess things up
|
---|
1269 | * (can create many copies of same child, etc).
|
---|
1270 | * Parent must create and use new socket instead. */
|
---|
1271 | new_udp_fd = socket(sep->se_family, SOCK_DGRAM, 0);
|
---|
1272 | dbg("new_udp_fd:%d\n", new_udp_fd);
|
---|
1273 | if (new_udp_fd < 0) { /* error: eat packet, forget about it */
|
---|
1274 | udp_err:
|
---|
1275 | recv(sep->se_fd, line, LINE_SIZE, MSG_DONTWAIT);
|
---|
1276 | continue;
|
---|
1277 | }
|
---|
1278 | setsockopt_reuseaddr(new_udp_fd);
|
---|
1279 | /* TODO: better do bind after fork in parent,
|
---|
1280 | * so that we don't have two wildcard bound sockets
|
---|
1281 | * even for a brief moment? */
|
---|
1282 | if (bind(new_udp_fd, &sep->se_lsa->u.sa, sep->se_lsa->len) < 0) {
|
---|
1283 | dbg("bind(new_udp_fd) failed\n");
|
---|
1284 | close(new_udp_fd);
|
---|
1285 | goto udp_err;
|
---|
1286 | }
|
---|
1287 | dbg("bind(new_udp_fd) succeeded\n");
|
---|
1288 | }
|
---|
1289 | }
|
---|
1290 |
|
---|
1291 | block_CHLD_HUP_ALRM(&omask);
|
---|
1292 | pid = 0;
|
---|
1293 | #ifdef INETD_BUILTINS_ENABLED
|
---|
1294 | /* do we need to fork? */
|
---|
1295 | if (sep->se_builtin == NULL
|
---|
1296 | || (sep->se_socktype == SOCK_STREAM
|
---|
1297 | && sep->se_builtin->bi_fork))
|
---|
1298 | #endif
|
---|
1299 | {
|
---|
1300 | if (sep->se_max != 0) {
|
---|
1301 | if (++sep->se_count == 1)
|
---|
1302 | sep->se_time = monotonic_sec();
|
---|
1303 | else if (sep->se_count >= sep->se_max) {
|
---|
1304 | unsigned now = monotonic_sec();
|
---|
1305 | /* did we accumulate se_max connects too quickly? */
|
---|
1306 | if (now - sep->se_time <= CNT_INTERVAL) {
|
---|
1307 | bb_error_msg("%s/%s: too many connections, pausing",
|
---|
1308 | sep->se_service, sep->se_proto);
|
---|
1309 | remove_fd_from_set(sep->se_fd);
|
---|
1310 | close(sep->se_fd);
|
---|
1311 | sep->se_fd = -1;
|
---|
1312 | sep->se_count = 0;
|
---|
1313 | rearm_alarm(); /* will revive it in RETRYTIME sec */
|
---|
1314 | restore_sigmask(&omask);
|
---|
1315 | maybe_close(new_udp_fd);
|
---|
1316 | maybe_close(accepted_fd);
|
---|
1317 | continue; /* -> check next fd in fd set */
|
---|
1318 | }
|
---|
1319 | sep->se_count = 0;
|
---|
1320 | }
|
---|
1321 | }
|
---|
1322 | /* on NOMMU, streamed chargen
|
---|
1323 | * builtin wouldn't work, but it is
|
---|
1324 | * not allowed on NOMMU (ifdefed out) */
|
---|
1325 | #ifdef INETD_BUILTINS_ENABLED
|
---|
1326 | if (BB_MMU && sep->se_builtin)
|
---|
1327 | pid = fork();
|
---|
1328 | else
|
---|
1329 | #endif
|
---|
1330 | pid = vfork();
|
---|
1331 |
|
---|
1332 | if (pid < 0) { /* fork error */
|
---|
1333 | bb_perror_msg("vfork"+1);
|
---|
1334 | sleep(1);
|
---|
1335 | restore_sigmask(&omask);
|
---|
1336 | maybe_close(new_udp_fd);
|
---|
1337 | maybe_close(accepted_fd);
|
---|
1338 | continue; /* -> check next fd in fd set */
|
---|
1339 | }
|
---|
1340 | if (pid == 0)
|
---|
1341 | pid--; /* -1: "we did fork and we are child" */
|
---|
1342 | }
|
---|
1343 | /* if pid == 0 here, we didn't fork */
|
---|
1344 |
|
---|
1345 | if (pid > 0) { /* parent */
|
---|
1346 | if (sep->se_wait) {
|
---|
1347 | /* wait: we passed socket to child,
|
---|
1348 | * will wait for child to terminate */
|
---|
1349 | sep->se_wait = pid;
|
---|
1350 | remove_fd_from_set(sep->se_fd);
|
---|
1351 | }
|
---|
1352 | if (new_udp_fd >= 0) {
|
---|
1353 | /* udp nowait: child connected the socket,
|
---|
1354 | * we created and will use new, unconnected one */
|
---|
1355 | xmove_fd(new_udp_fd, sep->se_fd);
|
---|
1356 | dbg("moved new_udp_fd:%d to sep->se_fd:%d\n", new_udp_fd, sep->se_fd);
|
---|
1357 | }
|
---|
1358 | restore_sigmask(&omask);
|
---|
1359 | maybe_close(accepted_fd);
|
---|
1360 | continue; /* -> check next fd in fd set */
|
---|
1361 | }
|
---|
1362 |
|
---|
1363 | /* we are either child or didn't fork at all */
|
---|
1364 | #ifdef INETD_BUILTINS_ENABLED
|
---|
1365 | if (sep->se_builtin) {
|
---|
1366 | if (pid) { /* "pid" is -1: we did fork */
|
---|
1367 | close(sep->se_fd); /* listening socket */
|
---|
1368 | dbg("closed sep->se_fd:%d\n", sep->se_fd);
|
---|
1369 | logmode = LOGMODE_NONE; /* make xwrite etc silent */
|
---|
1370 | }
|
---|
1371 | restore_sigmask(&omask);
|
---|
1372 | if (sep->se_socktype == SOCK_STREAM)
|
---|
1373 | sep->se_builtin->bi_stream_fn(ctrl, sep);
|
---|
1374 | else
|
---|
1375 | sep->se_builtin->bi_dgram_fn(ctrl, sep);
|
---|
1376 | if (pid) /* we did fork */
|
---|
1377 | _exit(EXIT_FAILURE);
|
---|
1378 | maybe_close(accepted_fd);
|
---|
1379 | continue; /* -> check next fd in fd set */
|
---|
1380 | }
|
---|
1381 | #endif
|
---|
1382 | /* child */
|
---|
1383 | setsid();
|
---|
1384 | /* "nowait" udp */
|
---|
1385 | if (new_udp_fd >= 0) {
|
---|
1386 | len_and_sockaddr *lsa;
|
---|
1387 | int r;
|
---|
1388 |
|
---|
1389 | close(new_udp_fd);
|
---|
1390 | dbg("closed new_udp_fd:%d\n", new_udp_fd);
|
---|
1391 | lsa = xzalloc_lsa(sep->se_family);
|
---|
1392 | /* peek at the packet and remember peer addr */
|
---|
1393 | r = recvfrom(ctrl, NULL, 0, MSG_PEEK|MSG_DONTWAIT,
|
---|
1394 | &lsa->u.sa, &lsa->len);
|
---|
1395 | if (r < 0)
|
---|
1396 | goto do_exit1;
|
---|
1397 | /* make this socket "connected" to peer addr:
|
---|
1398 | * only packets from this peer will be recv'ed,
|
---|
1399 | * and bare write()/send() will work on it */
|
---|
1400 | connect(ctrl, &lsa->u.sa, lsa->len);
|
---|
1401 | dbg("connected ctrl:%d to remote peer\n", ctrl);
|
---|
1402 | free(lsa);
|
---|
1403 | }
|
---|
1404 | /* prepare env and exec program */
|
---|
1405 | pwd = getpwnam(sep->se_user);
|
---|
1406 | if (pwd == NULL) {
|
---|
1407 | bb_error_msg("%s: no such %s", sep->se_user, "user");
|
---|
1408 | goto do_exit1;
|
---|
1409 | }
|
---|
1410 | if (sep->se_group && (grp = getgrnam(sep->se_group)) == NULL) {
|
---|
1411 | bb_error_msg("%s: no such %s", sep->se_group, "group");
|
---|
1412 | goto do_exit1;
|
---|
1413 | }
|
---|
1414 | if (real_uid != 0 && real_uid != pwd->pw_uid) {
|
---|
1415 | /* a user running private inetd */
|
---|
1416 | bb_error_msg("non-root must run services as himself");
|
---|
1417 | goto do_exit1;
|
---|
1418 | }
|
---|
1419 | if (pwd->pw_uid != 0) {
|
---|
1420 | if (sep->se_group)
|
---|
1421 | pwd->pw_gid = grp->gr_gid;
|
---|
1422 | /* initgroups, setgid, setuid: */
|
---|
1423 | change_identity(pwd);
|
---|
1424 | } else if (sep->se_group) {
|
---|
1425 | xsetgid(grp->gr_gid);
|
---|
1426 | setgroups(1, &grp->gr_gid);
|
---|
1427 | }
|
---|
1428 | if (rlim_ofile.rlim_cur != rlim_ofile_cur)
|
---|
1429 | if (setrlimit(RLIMIT_NOFILE, &rlim_ofile) < 0)
|
---|
1430 | bb_perror_msg("setrlimit");
|
---|
1431 |
|
---|
1432 | /* closelog(); - WRONG. we are after vfork,
|
---|
1433 | * this may confuse syslog() internal state.
|
---|
1434 | * Let's hope libc sets syslog fd to CLOEXEC...
|
---|
1435 | */
|
---|
1436 | xmove_fd(ctrl, STDIN_FILENO);
|
---|
1437 | xdup2(STDIN_FILENO, STDOUT_FILENO);
|
---|
1438 | dbg("moved ctrl:%d to fd 0,1[,2]\n", ctrl);
|
---|
1439 | /* manpages of inetd I managed to find either say
|
---|
1440 | * that stderr is also redirected to the network,
|
---|
1441 | * or do not talk about redirection at all (!) */
|
---|
1442 | if (!sep->se_wait) /* only for usual "tcp nowait" */
|
---|
1443 | xdup2(STDIN_FILENO, STDERR_FILENO);
|
---|
1444 | /* NB: among others, this loop closes listening sockets
|
---|
1445 | * for nowait stream children */
|
---|
1446 | for (sep2 = serv_list; sep2; sep2 = sep2->se_next)
|
---|
1447 | if (sep2->se_fd != ctrl)
|
---|
1448 | maybe_close(sep2->se_fd);
|
---|
1449 | sigaction_set(SIGPIPE, &saved_pipe_handler);
|
---|
1450 | restore_sigmask(&omask);
|
---|
1451 | dbg("execing:'%s'\n", sep->se_program);
|
---|
1452 | BB_EXECVP(sep->se_program, sep->se_argv);
|
---|
1453 | bb_perror_msg("can't execute '%s'", sep->se_program);
|
---|
1454 | do_exit1:
|
---|
1455 | /* eat packet in udp case */
|
---|
1456 | if (sep->se_socktype != SOCK_STREAM)
|
---|
1457 | recv(0, line, LINE_SIZE, MSG_DONTWAIT);
|
---|
1458 | _exit(EXIT_FAILURE);
|
---|
1459 | } /* for (sep = servtab...) */
|
---|
1460 | } /* for (;;) */
|
---|
1461 | }
|
---|
1462 |
|
---|
1463 | #if !BB_MMU
|
---|
1464 | static const char *const cat_args[] = { "cat", NULL };
|
---|
1465 | #endif
|
---|
1466 |
|
---|
1467 | /*
|
---|
1468 | * Internet services provided internally by inetd:
|
---|
1469 | */
|
---|
1470 | #if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_ECHO
|
---|
1471 | /* Echo service -- echo data back. */
|
---|
1472 | /* ARGSUSED */
|
---|
1473 | static void FAST_FUNC echo_stream(int s, servtab_t *sep UNUSED_PARAM)
|
---|
1474 | {
|
---|
1475 | #if BB_MMU
|
---|
1476 | while (1) {
|
---|
1477 | ssize_t sz = safe_read(s, line, LINE_SIZE);
|
---|
1478 | if (sz <= 0)
|
---|
1479 | break;
|
---|
1480 | xwrite(s, line, sz);
|
---|
1481 | }
|
---|
1482 | #else
|
---|
1483 | /* We are after vfork here! */
|
---|
1484 | /* move network socket to stdin/stdout */
|
---|
1485 | xmove_fd(s, STDIN_FILENO);
|
---|
1486 | xdup2(STDIN_FILENO, STDOUT_FILENO);
|
---|
1487 | /* no error messages please... */
|
---|
1488 | close(STDERR_FILENO);
|
---|
1489 | xopen(bb_dev_null, O_WRONLY);
|
---|
1490 | BB_EXECVP("cat", (char**)cat_args);
|
---|
1491 | /* on failure we return to main, which does exit(EXIT_FAILURE) */
|
---|
1492 | #endif
|
---|
1493 | }
|
---|
1494 | static void FAST_FUNC echo_dg(int s, servtab_t *sep)
|
---|
1495 | {
|
---|
1496 | enum { BUFSIZE = 12*1024 }; /* for jumbo sized packets! :) */
|
---|
1497 | char *buf = xmalloc(BUFSIZE); /* too big for stack */
|
---|
1498 | int sz;
|
---|
1499 | len_and_sockaddr *lsa = alloca(LSA_LEN_SIZE + sep->se_lsa->len);
|
---|
1500 |
|
---|
1501 | lsa->len = sep->se_lsa->len;
|
---|
1502 | /* dgram builtins are non-forking - DONT BLOCK! */
|
---|
1503 | sz = recvfrom(s, buf, BUFSIZE, MSG_DONTWAIT, &lsa->u.sa, &lsa->len);
|
---|
1504 | if (sz > 0)
|
---|
1505 | sendto(s, buf, sz, 0, &lsa->u.sa, lsa->len);
|
---|
1506 | free(buf);
|
---|
1507 | }
|
---|
1508 | #endif /* FEATURE_INETD_SUPPORT_BUILTIN_ECHO */
|
---|
1509 |
|
---|
1510 |
|
---|
1511 | #if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_DISCARD
|
---|
1512 | /* Discard service -- ignore data. */
|
---|
1513 | /* ARGSUSED */
|
---|
1514 | static void FAST_FUNC discard_stream(int s, servtab_t *sep UNUSED_PARAM)
|
---|
1515 | {
|
---|
1516 | #if BB_MMU
|
---|
1517 | while (safe_read(s, line, LINE_SIZE) > 0)
|
---|
1518 | continue;
|
---|
1519 | #else
|
---|
1520 | /* We are after vfork here! */
|
---|
1521 | /* move network socket to stdin */
|
---|
1522 | xmove_fd(s, STDIN_FILENO);
|
---|
1523 | /* discard output */
|
---|
1524 | close(STDOUT_FILENO);
|
---|
1525 | xopen(bb_dev_null, O_WRONLY);
|
---|
1526 | /* no error messages please... */
|
---|
1527 | xdup2(STDOUT_FILENO, STDERR_FILENO);
|
---|
1528 | BB_EXECVP("cat", (char**)cat_args);
|
---|
1529 | /* on failure we return to main, which does exit(EXIT_FAILURE) */
|
---|
1530 | #endif
|
---|
1531 | }
|
---|
1532 | /* ARGSUSED */
|
---|
1533 | static void FAST_FUNC discard_dg(int s, servtab_t *sep UNUSED_PARAM)
|
---|
1534 | {
|
---|
1535 | /* dgram builtins are non-forking - DONT BLOCK! */
|
---|
1536 | recv(s, line, LINE_SIZE, MSG_DONTWAIT);
|
---|
1537 | }
|
---|
1538 | #endif /* FEATURE_INETD_SUPPORT_BUILTIN_DISCARD */
|
---|
1539 |
|
---|
1540 |
|
---|
1541 | #if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_CHARGEN
|
---|
1542 | #define LINESIZ 72
|
---|
1543 | static void init_ring(void)
|
---|
1544 | {
|
---|
1545 | int i;
|
---|
1546 |
|
---|
1547 | end_ring = ring;
|
---|
1548 | for (i = ' '; i < 127; i++)
|
---|
1549 | *end_ring++ = i;
|
---|
1550 | }
|
---|
1551 | /* Character generator. MMU arches only. */
|
---|
1552 | /* ARGSUSED */
|
---|
1553 | static void FAST_FUNC chargen_stream(int s, servtab_t *sep UNUSED_PARAM)
|
---|
1554 | {
|
---|
1555 | char *rs;
|
---|
1556 | int len;
|
---|
1557 | char text[LINESIZ + 2];
|
---|
1558 |
|
---|
1559 | if (!end_ring) {
|
---|
1560 | init_ring();
|
---|
1561 | rs = ring;
|
---|
1562 | }
|
---|
1563 |
|
---|
1564 | text[LINESIZ] = '\r';
|
---|
1565 | text[LINESIZ + 1] = '\n';
|
---|
1566 | rs = ring;
|
---|
1567 | for (;;) {
|
---|
1568 | len = end_ring - rs;
|
---|
1569 | if (len >= LINESIZ)
|
---|
1570 | memmove(text, rs, LINESIZ);
|
---|
1571 | else {
|
---|
1572 | memmove(text, rs, len);
|
---|
1573 | memmove(text + len, ring, LINESIZ - len);
|
---|
1574 | }
|
---|
1575 | if (++rs == end_ring)
|
---|
1576 | rs = ring;
|
---|
1577 | xwrite(s, text, sizeof(text));
|
---|
1578 | }
|
---|
1579 | }
|
---|
1580 | /* ARGSUSED */
|
---|
1581 | static void FAST_FUNC chargen_dg(int s, servtab_t *sep)
|
---|
1582 | {
|
---|
1583 | int len;
|
---|
1584 | char text[LINESIZ + 2];
|
---|
1585 | len_and_sockaddr *lsa = alloca(LSA_LEN_SIZE + sep->se_lsa->len);
|
---|
1586 |
|
---|
1587 | /* Eat UDP packet which started it all */
|
---|
1588 | /* dgram builtins are non-forking - DONT BLOCK! */
|
---|
1589 | lsa->len = sep->se_lsa->len;
|
---|
1590 | if (recvfrom(s, text, sizeof(text), MSG_DONTWAIT, &lsa->u.sa, &lsa->len) < 0)
|
---|
1591 | return;
|
---|
1592 |
|
---|
1593 | if (!end_ring) {
|
---|
1594 | init_ring();
|
---|
1595 | ring_pos = ring;
|
---|
1596 | }
|
---|
1597 |
|
---|
1598 | len = end_ring - ring_pos;
|
---|
1599 | if (len >= LINESIZ)
|
---|
1600 | memmove(text, ring_pos, LINESIZ);
|
---|
1601 | else {
|
---|
1602 | memmove(text, ring_pos, len);
|
---|
1603 | memmove(text + len, ring, LINESIZ - len);
|
---|
1604 | }
|
---|
1605 | if (++ring_pos == end_ring)
|
---|
1606 | ring_pos = ring;
|
---|
1607 | text[LINESIZ] = '\r';
|
---|
1608 | text[LINESIZ + 1] = '\n';
|
---|
1609 | sendto(s, text, sizeof(text), 0, &lsa->u.sa, lsa->len);
|
---|
1610 | }
|
---|
1611 | #endif /* FEATURE_INETD_SUPPORT_BUILTIN_CHARGEN */
|
---|
1612 |
|
---|
1613 |
|
---|
1614 | #if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_TIME
|
---|
1615 | /*
|
---|
1616 | * Return a machine readable date and time, in the form of the
|
---|
1617 | * number of seconds since midnight, Jan 1, 1900. Since gettimeofday
|
---|
1618 | * returns the number of seconds since midnight, Jan 1, 1970,
|
---|
1619 | * we must add 2208988800 seconds to this figure to make up for
|
---|
1620 | * some seventy years Bell Labs was asleep.
|
---|
1621 | */
|
---|
1622 | static uint32_t machtime(void)
|
---|
1623 | {
|
---|
1624 | struct timeval tv;
|
---|
1625 |
|
---|
1626 | gettimeofday(&tv, NULL);
|
---|
1627 | return htonl((uint32_t)(tv.tv_sec + 2208988800));
|
---|
1628 | }
|
---|
1629 | /* ARGSUSED */
|
---|
1630 | static void FAST_FUNC machtime_stream(int s, servtab_t *sep UNUSED_PARAM)
|
---|
1631 | {
|
---|
1632 | uint32_t result;
|
---|
1633 |
|
---|
1634 | result = machtime();
|
---|
1635 | full_write(s, &result, sizeof(result));
|
---|
1636 | }
|
---|
1637 | static void FAST_FUNC machtime_dg(int s, servtab_t *sep)
|
---|
1638 | {
|
---|
1639 | uint32_t result;
|
---|
1640 | len_and_sockaddr *lsa = alloca(LSA_LEN_SIZE + sep->se_lsa->len);
|
---|
1641 |
|
---|
1642 | lsa->len = sep->se_lsa->len;
|
---|
1643 | if (recvfrom(s, line, LINE_SIZE, MSG_DONTWAIT, &lsa->u.sa, &lsa->len) < 0)
|
---|
1644 | return;
|
---|
1645 |
|
---|
1646 | result = machtime();
|
---|
1647 | sendto(s, &result, sizeof(result), 0, &lsa->u.sa, lsa->len);
|
---|
1648 | }
|
---|
1649 | #endif /* FEATURE_INETD_SUPPORT_BUILTIN_TIME */
|
---|
1650 |
|
---|
1651 |
|
---|
1652 | #if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_DAYTIME
|
---|
1653 | /* Return human-readable time of day */
|
---|
1654 | /* ARGSUSED */
|
---|
1655 | static void FAST_FUNC daytime_stream(int s, servtab_t *sep UNUSED_PARAM)
|
---|
1656 | {
|
---|
1657 | time_t t;
|
---|
1658 |
|
---|
1659 | time(&t);
|
---|
1660 | fdprintf(s, "%.24s\r\n", ctime(&t));
|
---|
1661 | }
|
---|
1662 | static void FAST_FUNC daytime_dg(int s, servtab_t *sep)
|
---|
1663 | {
|
---|
1664 | time_t t;
|
---|
1665 | len_and_sockaddr *lsa = alloca(LSA_LEN_SIZE + sep->se_lsa->len);
|
---|
1666 |
|
---|
1667 | lsa->len = sep->se_lsa->len;
|
---|
1668 | if (recvfrom(s, line, LINE_SIZE, MSG_DONTWAIT, &lsa->u.sa, &lsa->len) < 0)
|
---|
1669 | return;
|
---|
1670 |
|
---|
1671 | t = time(NULL);
|
---|
1672 | sprintf(line, "%.24s\r\n", ctime(&t));
|
---|
1673 | sendto(s, line, strlen(line), 0, &lsa->u.sa, lsa->len);
|
---|
1674 | }
|
---|
1675 | #endif /* FEATURE_INETD_SUPPORT_BUILTIN_DAYTIME */
|
---|