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 |
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174 | #if ENABLE_FEATURE_INETD_RPC
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175 | # if defined(__UCLIBC__) && ! defined(__UCLIBC_HAS_RPC__)
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176 | # error "You need to build uClibc with UCLIBC_HAS_RPC for NFS support"
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177 | # endif
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178 | # include <rpc/rpc.h>
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179 | # include <rpc/pmap_clnt.h>
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180 | #endif
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181 |
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182 | #if !BB_MMU
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183 | /* stream version of chargen is forking but not execing,
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184 | * can't do that (easily) on NOMMU */
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185 | #undef ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_CHARGEN
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186 | #define ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_CHARGEN 0
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187 | #endif
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188 |
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189 | #define CNT_INTERVAL 60 /* servers in CNT_INTERVAL sec. */
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190 | #define RETRYTIME 60 /* retry after bind or server fail */
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191 |
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192 | // TODO: explain, or get rid of setrlimit games
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193 |
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194 | #ifndef RLIMIT_NOFILE
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195 | #define RLIMIT_NOFILE RLIMIT_OFILE
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196 | #endif
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197 |
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198 | #ifndef OPEN_MAX
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199 | #define OPEN_MAX 64
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200 | #endif
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201 |
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202 | /* Reserve some descriptors, 3 stdio + at least: 1 log, 1 conf. file */
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203 | #define FD_MARGIN 8
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204 |
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205 | #if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_DISCARD \
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206 | || ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_ECHO \
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207 | || ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_CHARGEN \
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208 | || ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_TIME \
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209 | || ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_DAYTIME
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210 | # define INETD_BUILTINS_ENABLED
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211 | #endif
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212 |
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213 | typedef struct servtab_t {
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214 | /* The most frequently referenced one: */
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215 | int se_fd; /* open descriptor */
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216 | /* NB: 'biggest fields last' saves on code size (~250 bytes) */
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217 | /* [addr:]service socktype proto wait user[:group] prog [args] */
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218 | char *se_local_hostname; /* addr to listen on */
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219 | char *se_service; /* "80" or "www" or "mount/2[-3]" */
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220 | /* socktype is in se_socktype */ /* "stream" "dgram" "raw" "rdm" "seqpacket" */
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221 | char *se_proto; /* "unix" or "[rpc/]tcp[6]" */
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222 | #if ENABLE_FEATURE_INETD_RPC
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223 | int se_rpcprog; /* rpc program number */
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224 | int se_rpcver_lo; /* rpc program lowest version */
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225 | int se_rpcver_hi; /* rpc program highest version */
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226 | #define is_rpc_service(sep) ((sep)->se_rpcver_lo != 0)
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227 | #else
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228 | #define is_rpc_service(sep) 0
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229 | #endif
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230 | pid_t se_wait; /* 0:"nowait", 1:"wait", >1:"wait" */
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231 | /* and waiting for this pid */
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232 | socktype_t se_socktype; /* SOCK_STREAM/DGRAM/RDM/... */
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233 | family_t se_family; /* AF_UNIX/INET[6] */
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234 | /* se_proto_no is used by RPC code only... hmm */
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235 | smallint se_proto_no; /* IPPROTO_TCP/UDP, n/a for AF_UNIX */
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236 | smallint se_checked; /* looked at during merge */
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237 | unsigned se_max; /* allowed instances per minute */
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238 | unsigned se_count; /* number started since se_time */
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239 | unsigned se_time; /* when we started counting */
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240 | char *se_user; /* user name to run as */
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241 | char *se_group; /* group name to run as, can be NULL */
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242 | #ifdef INETD_BUILTINS_ENABLED
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243 | const struct builtin *se_builtin; /* if built-in, description */
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244 | #endif
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245 | struct servtab_t *se_next;
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246 | len_and_sockaddr *se_lsa;
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247 | char *se_program; /* server program */
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248 | #define MAXARGV 20
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249 | char *se_argv[MAXARGV + 1]; /* program arguments */
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250 | } servtab_t;
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251 |
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252 | #ifdef INETD_BUILTINS_ENABLED
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253 | /* Echo received data */
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254 | #if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_ECHO
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255 | static void FAST_FUNC echo_stream(int, servtab_t *);
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256 | static void FAST_FUNC echo_dg(int, servtab_t *);
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257 | #endif
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258 | /* Internet /dev/null */
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259 | #if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_DISCARD
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260 | static void FAST_FUNC discard_stream(int, servtab_t *);
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261 | static void FAST_FUNC discard_dg(int, servtab_t *);
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262 | #endif
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263 | /* Return 32 bit time since 1900 */
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264 | #if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_TIME
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265 | static void FAST_FUNC machtime_stream(int, servtab_t *);
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266 | static void FAST_FUNC machtime_dg(int, servtab_t *);
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267 | #endif
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268 | /* Return human-readable time */
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269 | #if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_DAYTIME
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270 | static void FAST_FUNC daytime_stream(int, servtab_t *);
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271 | static void FAST_FUNC daytime_dg(int, servtab_t *);
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272 | #endif
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273 | /* Familiar character generator */
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274 | #if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_CHARGEN
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275 | static void FAST_FUNC chargen_stream(int, servtab_t *);
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276 | static void FAST_FUNC chargen_dg(int, servtab_t *);
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277 | #endif
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278 |
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279 | struct builtin {
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280 | /* NB: not necessarily NUL terminated */
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281 | char bi_service7[7]; /* internally provided service name */
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282 | uint8_t bi_fork; /* 1 if stream fn should run in child */
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283 | void (*bi_stream_fn)(int, servtab_t *) FAST_FUNC;
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284 | void (*bi_dgram_fn)(int, servtab_t *) FAST_FUNC;
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285 | };
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286 |
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287 | static const struct builtin builtins[] = {
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288 | #if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_ECHO
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289 | { "echo", 1, echo_stream, echo_dg },
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290 | #endif
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291 | #if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_DISCARD
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292 | { "discard", 1, discard_stream, discard_dg },
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293 | #endif
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294 | #if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_CHARGEN
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295 | { "chargen", 1, chargen_stream, chargen_dg },
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296 | #endif
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297 | #if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_TIME
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298 | { "time", 0, machtime_stream, machtime_dg },
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299 | #endif
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300 | #if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_DAYTIME
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301 | { "daytime", 0, daytime_stream, daytime_dg },
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302 | #endif
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303 | };
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304 | #endif /* INETD_BUILTINS_ENABLED */
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305 |
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306 | struct globals {
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307 | rlim_t rlim_ofile_cur;
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308 | struct rlimit rlim_ofile;
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309 | servtab_t *serv_list;
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310 | int global_queuelen;
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311 | int maxsock; /* max fd# in allsock, -1: unknown */
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312 | /* whenever maxsock grows, prev_maxsock is set to new maxsock,
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313 | * but if maxsock is set to -1, prev_maxsock is not changed */
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314 | int prev_maxsock;
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315 | unsigned max_concurrency;
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316 | smallint alarm_armed;
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317 | uid_t real_uid; /* user ID who ran us */
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318 | const char *config_filename;
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319 | parser_t *parser;
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320 | char *default_local_hostname;
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321 | #if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_CHARGEN
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322 | char *end_ring;
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323 | char *ring_pos;
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324 | char ring[128];
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325 | #endif
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326 | fd_set allsock;
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327 | /* Used in next_line(), and as scratch read buffer */
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328 | char line[256]; /* _at least_ 256, see LINE_SIZE */
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329 | } FIX_ALIASING;
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330 | #define G (*(struct globals*)&bb_common_bufsiz1)
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331 | enum { LINE_SIZE = COMMON_BUFSIZE - offsetof(struct globals, line) };
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332 | struct BUG_G_too_big {
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333 | char BUG_G_too_big[sizeof(G) <= COMMON_BUFSIZE ? 1 : -1];
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334 | };
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335 | #define rlim_ofile_cur (G.rlim_ofile_cur )
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336 | #define rlim_ofile (G.rlim_ofile )
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337 | #define serv_list (G.serv_list )
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338 | #define global_queuelen (G.global_queuelen)
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339 | #define maxsock (G.maxsock )
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340 | #define prev_maxsock (G.prev_maxsock )
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341 | #define max_concurrency (G.max_concurrency)
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342 | #define alarm_armed (G.alarm_armed )
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343 | #define real_uid (G.real_uid )
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344 | #define config_filename (G.config_filename)
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345 | #define parser (G.parser )
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346 | #define default_local_hostname (G.default_local_hostname)
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347 | #define first_ps_byte (G.first_ps_byte )
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348 | #define last_ps_byte (G.last_ps_byte )
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349 | #define end_ring (G.end_ring )
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350 | #define ring_pos (G.ring_pos )
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351 | #define ring (G.ring )
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352 | #define allsock (G.allsock )
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353 | #define line (G.line )
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354 | #define INIT_G() do { \
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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?
|
---|
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 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 | goto more;
|
---|
679 | }
|
---|
680 | } else
|
---|
681 | sep->se_local_hostname = xstrdup(default_local_hostname);
|
---|
682 |
|
---|
683 | /* service socktype proto wait user[:group] prog [args] */
|
---|
684 | sep->se_service = xstrdup(arg);
|
---|
685 |
|
---|
686 | /* socktype proto wait user[:group] prog [args] */
|
---|
687 | if (argc < 6) {
|
---|
688 | parse_err:
|
---|
689 | bb_error_msg("parse error on line %u, line is ignored",
|
---|
690 | parser->lineno);
|
---|
691 | free_servtab_strings(sep);
|
---|
692 | /* Just "goto more" can make sep to carry over e.g.
|
---|
693 | * "rpc"-ness (by having se_rpcver_lo != 0).
|
---|
694 | * We will be more paranoid: */
|
---|
695 | free(sep);
|
---|
696 | goto new;
|
---|
697 | }
|
---|
698 |
|
---|
699 | {
|
---|
700 | static const int8_t SOCK_xxx[] ALIGN1 = {
|
---|
701 | -1,
|
---|
702 | SOCK_STREAM, SOCK_DGRAM, SOCK_RDM,
|
---|
703 | SOCK_SEQPACKET, SOCK_RAW
|
---|
704 | };
|
---|
705 | sep->se_socktype = SOCK_xxx[1 + index_in_strings(
|
---|
706 | "stream""\0" "dgram""\0" "rdm""\0"
|
---|
707 | "seqpacket""\0" "raw""\0"
|
---|
708 | , token[1])];
|
---|
709 | }
|
---|
710 |
|
---|
711 | /* {unix,[rpc/]{tcp,udp}[6]} wait user[:group] prog [args] */
|
---|
712 | sep->se_proto = arg = xstrdup(token[2]);
|
---|
713 | if (strcmp(arg, "unix") == 0) {
|
---|
714 | sep->se_family = AF_UNIX;
|
---|
715 | } else {
|
---|
716 | char *six;
|
---|
717 | sep->se_family = AF_INET;
|
---|
718 | six = last_char_is(arg, '6');
|
---|
719 | if (six) {
|
---|
720 | #if ENABLE_FEATURE_IPV6
|
---|
721 | *six = '\0';
|
---|
722 | sep->se_family = AF_INET6;
|
---|
723 | #else
|
---|
724 | bb_error_msg("%s: no support for IPv6", sep->se_proto);
|
---|
725 | goto parse_err;
|
---|
726 | #endif
|
---|
727 | }
|
---|
728 | if (strncmp(arg, "rpc/", 4) == 0) {
|
---|
729 | #if ENABLE_FEATURE_INETD_RPC
|
---|
730 | unsigned n;
|
---|
731 | arg += 4;
|
---|
732 | p = strchr(sep->se_service, '/');
|
---|
733 | if (p == NULL) {
|
---|
734 | bb_error_msg("no rpc version: '%s'", sep->se_service);
|
---|
735 | goto parse_err;
|
---|
736 | }
|
---|
737 | *p++ = '\0';
|
---|
738 | n = bb_strtou(p, &p, 10);
|
---|
739 | if (n > INT_MAX) {
|
---|
740 | bad_ver_spec:
|
---|
741 | bb_error_msg("bad rpc version");
|
---|
742 | goto parse_err;
|
---|
743 | }
|
---|
744 | sep->se_rpcver_lo = sep->se_rpcver_hi = n;
|
---|
745 | if (*p == '-') {
|
---|
746 | p++;
|
---|
747 | n = bb_strtou(p, &p, 10);
|
---|
748 | if (n > INT_MAX || (int)n < sep->se_rpcver_lo)
|
---|
749 | goto bad_ver_spec;
|
---|
750 | sep->se_rpcver_hi = n;
|
---|
751 | }
|
---|
752 | if (*p != '\0')
|
---|
753 | goto bad_ver_spec;
|
---|
754 | #else
|
---|
755 | bb_error_msg("no support for rpc services");
|
---|
756 | goto parse_err;
|
---|
757 | #endif
|
---|
758 | }
|
---|
759 | /* we don't really need getprotobyname()! */
|
---|
760 | if (strcmp(arg, "tcp") == 0)
|
---|
761 | sep->se_proto_no = IPPROTO_TCP; /* = 6 */
|
---|
762 | if (strcmp(arg, "udp") == 0)
|
---|
763 | sep->se_proto_no = IPPROTO_UDP; /* = 17 */
|
---|
764 | if (six)
|
---|
765 | *six = '6';
|
---|
766 | if (!sep->se_proto_no) /* not tcp/udp?? */
|
---|
767 | goto parse_err;
|
---|
768 | }
|
---|
769 |
|
---|
770 | /* [no]wait[.max] user[:group] prog [args] */
|
---|
771 | arg = token[3];
|
---|
772 | sep->se_max = max_concurrency;
|
---|
773 | p = strchr(arg, '.');
|
---|
774 | if (p) {
|
---|
775 | *p++ = '\0';
|
---|
776 | sep->se_max = bb_strtou(p, NULL, 10);
|
---|
777 | if (errno)
|
---|
778 | goto parse_err;
|
---|
779 | }
|
---|
780 | sep->se_wait = (arg[0] != 'n' || arg[1] != 'o');
|
---|
781 | if (!sep->se_wait) /* "no" seen */
|
---|
782 | arg += 2;
|
---|
783 | if (strcmp(arg, "wait") != 0)
|
---|
784 | goto parse_err;
|
---|
785 |
|
---|
786 | /* user[:group] prog [args] */
|
---|
787 | sep->se_user = xstrdup(token[4]);
|
---|
788 | arg = strchr(sep->se_user, '.');
|
---|
789 | if (arg == NULL)
|
---|
790 | arg = strchr(sep->se_user, ':');
|
---|
791 | if (arg) {
|
---|
792 | *arg++ = '\0';
|
---|
793 | sep->se_group = xstrdup(arg);
|
---|
794 | }
|
---|
795 |
|
---|
796 | /* prog [args] */
|
---|
797 | sep->se_program = xstrdup(token[5]);
|
---|
798 | #ifdef INETD_BUILTINS_ENABLED
|
---|
799 | if (strcmp(sep->se_program, "internal") == 0
|
---|
800 | && strlen(sep->se_service) <= 7
|
---|
801 | && (sep->se_socktype == SOCK_STREAM
|
---|
802 | || sep->se_socktype == SOCK_DGRAM)
|
---|
803 | ) {
|
---|
804 | unsigned i;
|
---|
805 | for (i = 0; i < ARRAY_SIZE(builtins); i++)
|
---|
806 | if (strncmp(builtins[i].bi_service7, sep->se_service, 7) == 0)
|
---|
807 | goto found_bi;
|
---|
808 | bb_error_msg("unknown internal service %s", sep->se_service);
|
---|
809 | goto parse_err;
|
---|
810 | found_bi:
|
---|
811 | sep->se_builtin = &builtins[i];
|
---|
812 | /* stream builtins must be "nowait", dgram must be "wait" */
|
---|
813 | if (sep->se_wait != (sep->se_socktype == SOCK_DGRAM))
|
---|
814 | goto parse_err;
|
---|
815 | }
|
---|
816 | #endif
|
---|
817 | argc = 0;
|
---|
818 | while ((arg = token[6+argc]) != NULL && argc < MAXARGV)
|
---|
819 | sep->se_argv[argc++] = xstrdup(arg);
|
---|
820 | /* Some inetd.conf files have no argv's, not even argv[0].
|
---|
821 | * Fix them up.
|
---|
822 | * (Technically, programs can be execed with argv[0] = NULL,
|
---|
823 | * but many programs do not like that at all) */
|
---|
824 | if (argc == 0)
|
---|
825 | sep->se_argv[0] = xstrdup(sep->se_program);
|
---|
826 |
|
---|
827 | /* catch mixups. "<service> stream udp ..." == wtf */
|
---|
828 | if (sep->se_socktype == SOCK_STREAM) {
|
---|
829 | if (sep->se_proto_no == IPPROTO_UDP)
|
---|
830 | goto parse_err;
|
---|
831 | }
|
---|
832 | if (sep->se_socktype == SOCK_DGRAM) {
|
---|
833 | if (sep->se_proto_no == IPPROTO_TCP)
|
---|
834 | goto parse_err;
|
---|
835 | }
|
---|
836 |
|
---|
837 | // bb_info_msg(
|
---|
838 | // "ENTRY[%s][%s][%s][%d][%d][%d][%d][%d][%s][%s][%s]",
|
---|
839 | // sep->se_local_hostname, sep->se_service, sep->se_proto, sep->se_wait, sep->se_proto_no,
|
---|
840 | // sep->se_max, sep->se_count, sep->se_time, sep->se_user, sep->se_group, sep->se_program);
|
---|
841 |
|
---|
842 | /* check if the hostname specifier is a comma separated list
|
---|
843 | * of hostnames. we'll make new entries for each address. */
|
---|
844 | while ((hostdelim = strrchr(sep->se_local_hostname, ',')) != NULL) {
|
---|
845 | nsep = dup_servtab(sep);
|
---|
846 | /* NUL terminate the hostname field of the existing entry,
|
---|
847 | * and make a dup for the new entry. */
|
---|
848 | *hostdelim++ = '\0';
|
---|
849 | nsep->se_local_hostname = xstrdup(hostdelim);
|
---|
850 | nsep->se_next = sep->se_next;
|
---|
851 | sep->se_next = nsep;
|
---|
852 | }
|
---|
853 |
|
---|
854 | /* was doing it here: */
|
---|
855 | /* DNS resolution, create copies for each IP address */
|
---|
856 | /* IPv6-ization destroyed it :( */
|
---|
857 |
|
---|
858 | return sep;
|
---|
859 | }
|
---|
860 |
|
---|
861 | static servtab_t *insert_in_servlist(servtab_t *cp)
|
---|
862 | {
|
---|
863 | servtab_t *sep;
|
---|
864 | sigset_t omask;
|
---|
865 |
|
---|
866 | sep = new_servtab();
|
---|
867 | *sep = *cp; /* struct copy */
|
---|
868 | sep->se_fd = -1;
|
---|
869 | #if ENABLE_FEATURE_INETD_RPC
|
---|
870 | sep->se_rpcprog = -1;
|
---|
871 | #endif
|
---|
872 | block_CHLD_HUP_ALRM(&omask);
|
---|
873 | sep->se_next = serv_list;
|
---|
874 | serv_list = sep;
|
---|
875 | restore_sigmask(&omask);
|
---|
876 | return sep;
|
---|
877 | }
|
---|
878 |
|
---|
879 | static int same_serv_addr_proto(servtab_t *old, servtab_t *new)
|
---|
880 | {
|
---|
881 | if (strcmp(old->se_local_hostname, new->se_local_hostname) != 0)
|
---|
882 | return 0;
|
---|
883 | if (strcmp(old->se_service, new->se_service) != 0)
|
---|
884 | return 0;
|
---|
885 | if (strcmp(old->se_proto, new->se_proto) != 0)
|
---|
886 | return 0;
|
---|
887 | return 1;
|
---|
888 | }
|
---|
889 |
|
---|
890 | static void reread_config_file(int sig UNUSED_PARAM)
|
---|
891 | {
|
---|
892 | servtab_t *sep, *cp, **sepp;
|
---|
893 | len_and_sockaddr *lsa;
|
---|
894 | sigset_t omask;
|
---|
895 | unsigned n;
|
---|
896 | uint16_t port;
|
---|
897 | int save_errno = errno;
|
---|
898 |
|
---|
899 | if (!reopen_config_file())
|
---|
900 | goto ret;
|
---|
901 | for (sep = serv_list; sep; sep = sep->se_next)
|
---|
902 | sep->se_checked = 0;
|
---|
903 |
|
---|
904 | goto first_line;
|
---|
905 | while (1) {
|
---|
906 | if (cp == NULL) {
|
---|
907 | first_line:
|
---|
908 | cp = parse_one_line();
|
---|
909 | if (cp == NULL)
|
---|
910 | break;
|
---|
911 | }
|
---|
912 | for (sep = serv_list; sep; sep = sep->se_next)
|
---|
913 | if (same_serv_addr_proto(sep, cp))
|
---|
914 | goto equal_servtab;
|
---|
915 | /* not an "equal" servtab */
|
---|
916 | sep = insert_in_servlist(cp);
|
---|
917 | goto after_check;
|
---|
918 | equal_servtab:
|
---|
919 | {
|
---|
920 | int i;
|
---|
921 |
|
---|
922 | block_CHLD_HUP_ALRM(&omask);
|
---|
923 | #if ENABLE_FEATURE_INETD_RPC
|
---|
924 | if (is_rpc_service(sep))
|
---|
925 | unregister_rpc(sep);
|
---|
926 | sep->se_rpcver_lo = cp->se_rpcver_lo;
|
---|
927 | sep->se_rpcver_hi = cp->se_rpcver_hi;
|
---|
928 | #endif
|
---|
929 | if (cp->se_wait == 0) {
|
---|
930 | /* New config says "nowait". If old one
|
---|
931 | * was "wait", we currently may be waiting
|
---|
932 | * for a child (and not accepting connects).
|
---|
933 | * Stop waiting, start listening again.
|
---|
934 | * (if it's not true, this op is harmless) */
|
---|
935 | add_fd_to_set(sep->se_fd);
|
---|
936 | }
|
---|
937 | sep->se_wait = cp->se_wait;
|
---|
938 | sep->se_max = cp->se_max;
|
---|
939 | /* string fields need more love - we don't want to leak them */
|
---|
940 | #define SWAP(type, a, b) do { type c = (type)a; a = (type)b; b = (type)c; } while (0)
|
---|
941 | SWAP(char*, sep->se_user, cp->se_user);
|
---|
942 | SWAP(char*, sep->se_group, cp->se_group);
|
---|
943 | SWAP(char*, sep->se_program, cp->se_program);
|
---|
944 | for (i = 0; i < MAXARGV; i++)
|
---|
945 | SWAP(char*, sep->se_argv[i], cp->se_argv[i]);
|
---|
946 | #undef SWAP
|
---|
947 | restore_sigmask(&omask);
|
---|
948 | free_servtab_strings(cp);
|
---|
949 | }
|
---|
950 | after_check:
|
---|
951 | /* cp->string_fields are consumed by insert_in_servlist()
|
---|
952 | * or freed at this point, cp itself is not yet freed. */
|
---|
953 | sep->se_checked = 1;
|
---|
954 |
|
---|
955 | /* create new len_and_sockaddr */
|
---|
956 | switch (sep->se_family) {
|
---|
957 | struct sockaddr_un *sun;
|
---|
958 | case AF_UNIX:
|
---|
959 | lsa = xzalloc_lsa(AF_UNIX);
|
---|
960 | sun = (struct sockaddr_un*)&lsa->u.sa;
|
---|
961 | safe_strncpy(sun->sun_path, sep->se_service, sizeof(sun->sun_path));
|
---|
962 | break;
|
---|
963 |
|
---|
964 | default: /* case AF_INET, case AF_INET6 */
|
---|
965 | n = bb_strtou(sep->se_service, NULL, 10);
|
---|
966 | #if ENABLE_FEATURE_INETD_RPC
|
---|
967 | if (is_rpc_service(sep)) {
|
---|
968 | sep->se_rpcprog = n;
|
---|
969 | if (errno) { /* se_service is not numeric */
|
---|
970 | struct rpcent *rp = getrpcbyname(sep->se_service);
|
---|
971 | if (rp == NULL) {
|
---|
972 | bb_error_msg("%s: unknown rpc service", sep->se_service);
|
---|
973 | goto next_cp;
|
---|
974 | }
|
---|
975 | sep->se_rpcprog = rp->r_number;
|
---|
976 | }
|
---|
977 | if (sep->se_fd == -1)
|
---|
978 | prepare_socket_fd(sep);
|
---|
979 | if (sep->se_fd != -1)
|
---|
980 | register_rpc(sep);
|
---|
981 | goto next_cp;
|
---|
982 | }
|
---|
983 | #endif
|
---|
984 | /* what port to listen on? */
|
---|
985 | port = htons(n);
|
---|
986 | if (errno || n > 0xffff) { /* se_service is not numeric */
|
---|
987 | char protoname[4];
|
---|
988 | struct servent *sp;
|
---|
989 | /* can result only in "tcp" or "udp": */
|
---|
990 | safe_strncpy(protoname, sep->se_proto, 4);
|
---|
991 | sp = getservbyname(sep->se_service, protoname);
|
---|
992 | if (sp == NULL) {
|
---|
993 | bb_error_msg("%s/%s: unknown service",
|
---|
994 | sep->se_service, sep->se_proto);
|
---|
995 | goto next_cp;
|
---|
996 | }
|
---|
997 | port = sp->s_port;
|
---|
998 | }
|
---|
999 | if (LONE_CHAR(sep->se_local_hostname, '*')) {
|
---|
1000 | lsa = xzalloc_lsa(sep->se_family);
|
---|
1001 | set_nport(&lsa->u.sa, port);
|
---|
1002 | } else {
|
---|
1003 | lsa = host_and_af2sockaddr(sep->se_local_hostname,
|
---|
1004 | ntohs(port), sep->se_family);
|
---|
1005 | if (!lsa) {
|
---|
1006 | bb_error_msg("%s/%s: unknown host '%s'",
|
---|
1007 | sep->se_service, sep->se_proto,
|
---|
1008 | sep->se_local_hostname);
|
---|
1009 | goto next_cp;
|
---|
1010 | }
|
---|
1011 | }
|
---|
1012 | break;
|
---|
1013 | } /* end of "switch (sep->se_family)" */
|
---|
1014 |
|
---|
1015 | /* did lsa change? Then close/open */
|
---|
1016 | if (sep->se_lsa == NULL
|
---|
1017 | || lsa->len != sep->se_lsa->len
|
---|
1018 | || memcmp(&lsa->u.sa, &sep->se_lsa->u.sa, lsa->len) != 0
|
---|
1019 | ) {
|
---|
1020 | remove_fd_from_set(sep->se_fd);
|
---|
1021 | maybe_close(sep->se_fd);
|
---|
1022 | free(sep->se_lsa);
|
---|
1023 | sep->se_lsa = lsa;
|
---|
1024 | sep->se_fd = -1;
|
---|
1025 | } else {
|
---|
1026 | free(lsa);
|
---|
1027 | }
|
---|
1028 | if (sep->se_fd == -1)
|
---|
1029 | prepare_socket_fd(sep);
|
---|
1030 | next_cp:
|
---|
1031 | sep = cp->se_next;
|
---|
1032 | free(cp);
|
---|
1033 | cp = sep;
|
---|
1034 | } /* end of "while (1) parse lines" */
|
---|
1035 | close_config_file();
|
---|
1036 |
|
---|
1037 | /* Purge anything not looked at above - these are stale entries,
|
---|
1038 | * new config file doesnt have them. */
|
---|
1039 | block_CHLD_HUP_ALRM(&omask);
|
---|
1040 | sepp = &serv_list;
|
---|
1041 | while ((sep = *sepp) != NULL) {
|
---|
1042 | if (sep->se_checked) {
|
---|
1043 | sepp = &sep->se_next;
|
---|
1044 | continue;
|
---|
1045 | }
|
---|
1046 | *sepp = sep->se_next;
|
---|
1047 | remove_fd_from_set(sep->se_fd);
|
---|
1048 | maybe_close(sep->se_fd);
|
---|
1049 | #if ENABLE_FEATURE_INETD_RPC
|
---|
1050 | if (is_rpc_service(sep))
|
---|
1051 | unregister_rpc(sep);
|
---|
1052 | #endif
|
---|
1053 | if (sep->se_family == AF_UNIX)
|
---|
1054 | unlink(sep->se_service);
|
---|
1055 | free_servtab_strings(sep);
|
---|
1056 | free(sep);
|
---|
1057 | }
|
---|
1058 | restore_sigmask(&omask);
|
---|
1059 | ret:
|
---|
1060 | errno = save_errno;
|
---|
1061 | }
|
---|
1062 |
|
---|
1063 | static void reap_child(int sig UNUSED_PARAM)
|
---|
1064 | {
|
---|
1065 | pid_t pid;
|
---|
1066 | int status;
|
---|
1067 | servtab_t *sep;
|
---|
1068 | int save_errno = errno;
|
---|
1069 |
|
---|
1070 | for (;;) {
|
---|
1071 | pid = wait_any_nohang(&status);
|
---|
1072 | if (pid <= 0)
|
---|
1073 | break;
|
---|
1074 | for (sep = serv_list; sep; sep = sep->se_next) {
|
---|
1075 | if (sep->se_wait != pid)
|
---|
1076 | continue;
|
---|
1077 | /* One of our "wait" services */
|
---|
1078 | if (WIFEXITED(status) && WEXITSTATUS(status))
|
---|
1079 | bb_error_msg("%s: exit status %u",
|
---|
1080 | sep->se_program, WEXITSTATUS(status));
|
---|
1081 | else if (WIFSIGNALED(status))
|
---|
1082 | bb_error_msg("%s: exit signal %u",
|
---|
1083 | sep->se_program, WTERMSIG(status));
|
---|
1084 | sep->se_wait = 1;
|
---|
1085 | add_fd_to_set(sep->se_fd);
|
---|
1086 | break;
|
---|
1087 | }
|
---|
1088 | }
|
---|
1089 | errno = save_errno;
|
---|
1090 | }
|
---|
1091 |
|
---|
1092 | static void retry_network_setup(int sig UNUSED_PARAM)
|
---|
1093 | {
|
---|
1094 | int save_errno = errno;
|
---|
1095 | servtab_t *sep;
|
---|
1096 |
|
---|
1097 | alarm_armed = 0;
|
---|
1098 | for (sep = serv_list; sep; sep = sep->se_next) {
|
---|
1099 | if (sep->se_fd == -1) {
|
---|
1100 | prepare_socket_fd(sep);
|
---|
1101 | #if ENABLE_FEATURE_INETD_RPC
|
---|
1102 | if (sep->se_fd != -1 && is_rpc_service(sep))
|
---|
1103 | register_rpc(sep);
|
---|
1104 | #endif
|
---|
1105 | }
|
---|
1106 | }
|
---|
1107 | errno = save_errno;
|
---|
1108 | }
|
---|
1109 |
|
---|
1110 | static void clean_up_and_exit(int sig UNUSED_PARAM)
|
---|
1111 | {
|
---|
1112 | servtab_t *sep;
|
---|
1113 |
|
---|
1114 | /* XXX signal race walking sep list */
|
---|
1115 | for (sep = serv_list; sep; sep = sep->se_next) {
|
---|
1116 | if (sep->se_fd == -1)
|
---|
1117 | continue;
|
---|
1118 |
|
---|
1119 | switch (sep->se_family) {
|
---|
1120 | case AF_UNIX:
|
---|
1121 | unlink(sep->se_service);
|
---|
1122 | break;
|
---|
1123 | default: /* case AF_INET, AF_INET6 */
|
---|
1124 | #if ENABLE_FEATURE_INETD_RPC
|
---|
1125 | if (sep->se_wait == 1 && is_rpc_service(sep))
|
---|
1126 | unregister_rpc(sep); /* XXX signal race */
|
---|
1127 | #endif
|
---|
1128 | break;
|
---|
1129 | }
|
---|
1130 | if (ENABLE_FEATURE_CLEAN_UP)
|
---|
1131 | close(sep->se_fd);
|
---|
1132 | }
|
---|
1133 | remove_pidfile(CONFIG_PID_FILE_PATH "/inetd.pid");
|
---|
1134 | exit(EXIT_SUCCESS);
|
---|
1135 | }
|
---|
1136 |
|
---|
1137 | int inetd_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
|
---|
1138 | int inetd_main(int argc UNUSED_PARAM, char **argv)
|
---|
1139 | {
|
---|
1140 | struct sigaction sa, saved_pipe_handler;
|
---|
1141 | servtab_t *sep, *sep2;
|
---|
1142 | struct passwd *pwd;
|
---|
1143 | struct group *grp = grp; /* for compiler */
|
---|
1144 | int opt;
|
---|
1145 | pid_t pid;
|
---|
1146 | sigset_t omask;
|
---|
1147 |
|
---|
1148 | INIT_G();
|
---|
1149 |
|
---|
1150 | real_uid = getuid();
|
---|
1151 | if (real_uid != 0) /* run by non-root user */
|
---|
1152 | config_filename = NULL;
|
---|
1153 |
|
---|
1154 | opt_complementary = "R+:q+"; /* -q N, -R N */
|
---|
1155 | opt = getopt32(argv, "R:feq:", &max_concurrency, &global_queuelen);
|
---|
1156 | argv += optind;
|
---|
1157 | //argc -= optind;
|
---|
1158 | if (argv[0])
|
---|
1159 | config_filename = argv[0];
|
---|
1160 | if (config_filename == NULL)
|
---|
1161 | bb_error_msg_and_die("non-root must specify config file");
|
---|
1162 | if (!(opt & 2))
|
---|
1163 | bb_daemonize_or_rexec(0, argv - optind);
|
---|
1164 | else
|
---|
1165 | bb_sanitize_stdio();
|
---|
1166 | if (!(opt & 4)) {
|
---|
1167 | /* LOG_NDELAY: connect to syslog daemon NOW.
|
---|
1168 | * Otherwise, we may open syslog socket
|
---|
1169 | * in vforked child, making opened fds and syslog()
|
---|
1170 | * internal state inconsistent.
|
---|
1171 | * This was observed to leak file descriptors. */
|
---|
1172 | openlog(applet_name, LOG_PID | LOG_NDELAY, LOG_DAEMON);
|
---|
1173 | logmode = LOGMODE_SYSLOG;
|
---|
1174 | }
|
---|
1175 |
|
---|
1176 | if (real_uid == 0) {
|
---|
1177 | /* run by root, ensure groups vector gets trashed */
|
---|
1178 | gid_t gid = getgid();
|
---|
1179 | setgroups(1, &gid);
|
---|
1180 | }
|
---|
1181 |
|
---|
1182 | write_pidfile(CONFIG_PID_FILE_PATH "/inetd.pid");
|
---|
1183 |
|
---|
1184 | /* never fails under Linux (except if you pass it bad arguments) */
|
---|
1185 | getrlimit(RLIMIT_NOFILE, &rlim_ofile);
|
---|
1186 | rlim_ofile_cur = rlim_ofile.rlim_cur;
|
---|
1187 | if (rlim_ofile_cur == RLIM_INFINITY) /* ! */
|
---|
1188 | rlim_ofile_cur = OPEN_MAX;
|
---|
1189 |
|
---|
1190 | memset(&sa, 0, sizeof(sa));
|
---|
1191 | /*sigemptyset(&sa.sa_mask); - memset did it */
|
---|
1192 | sigaddset(&sa.sa_mask, SIGALRM);
|
---|
1193 | sigaddset(&sa.sa_mask, SIGCHLD);
|
---|
1194 | sigaddset(&sa.sa_mask, SIGHUP);
|
---|
1195 | //FIXME: explain why no SA_RESTART
|
---|
1196 | //FIXME: retry_network_setup is unsafe to run in signal handler (many reasons)!
|
---|
1197 | sa.sa_handler = retry_network_setup;
|
---|
1198 | sigaction_set(SIGALRM, &sa);
|
---|
1199 | //FIXME: reread_config_file is unsafe to run in signal handler(many reasons)!
|
---|
1200 | sa.sa_handler = reread_config_file;
|
---|
1201 | sigaction_set(SIGHUP, &sa);
|
---|
1202 | //FIXME: reap_child is unsafe to run in signal handler (uses stdio)!
|
---|
1203 | sa.sa_handler = reap_child;
|
---|
1204 | sigaction_set(SIGCHLD, &sa);
|
---|
1205 | //FIXME: clean_up_and_exit is unsafe to run in signal handler (uses stdio)!
|
---|
1206 | sa.sa_handler = clean_up_and_exit;
|
---|
1207 | sigaction_set(SIGTERM, &sa);
|
---|
1208 | sa.sa_handler = clean_up_and_exit;
|
---|
1209 | sigaction_set(SIGINT, &sa);
|
---|
1210 | sa.sa_handler = SIG_IGN;
|
---|
1211 | sigaction(SIGPIPE, &sa, &saved_pipe_handler);
|
---|
1212 |
|
---|
1213 | reread_config_file(SIGHUP); /* load config from file */
|
---|
1214 |
|
---|
1215 | for (;;) {
|
---|
1216 | int ready_fd_cnt;
|
---|
1217 | int ctrl, accepted_fd, new_udp_fd;
|
---|
1218 | fd_set readable;
|
---|
1219 |
|
---|
1220 | if (maxsock < 0)
|
---|
1221 | recalculate_maxsock();
|
---|
1222 |
|
---|
1223 | readable = allsock; /* struct copy */
|
---|
1224 | /* if there are no fds to wait on, we will block
|
---|
1225 | * until signal wakes us up (maxsock == 0, but readable
|
---|
1226 | * never contains fds 0 and 1...) */
|
---|
1227 | ready_fd_cnt = select(maxsock + 1, &readable, NULL, NULL, NULL);
|
---|
1228 | if (ready_fd_cnt < 0) {
|
---|
1229 | if (errno != EINTR) {
|
---|
1230 | bb_perror_msg("select");
|
---|
1231 | sleep(1);
|
---|
1232 | }
|
---|
1233 | continue;
|
---|
1234 | }
|
---|
1235 | dbg("ready_fd_cnt:%d\n", ready_fd_cnt);
|
---|
1236 |
|
---|
1237 | for (sep = serv_list; ready_fd_cnt && sep; sep = sep->se_next) {
|
---|
1238 | if (sep->se_fd == -1 || !FD_ISSET(sep->se_fd, &readable))
|
---|
1239 | continue;
|
---|
1240 |
|
---|
1241 | dbg("ready fd:%d\n", sep->se_fd);
|
---|
1242 | ready_fd_cnt--;
|
---|
1243 | ctrl = sep->se_fd;
|
---|
1244 | accepted_fd = -1;
|
---|
1245 | new_udp_fd = -1;
|
---|
1246 | if (!sep->se_wait) {
|
---|
1247 | if (sep->se_socktype == SOCK_STREAM) {
|
---|
1248 | ctrl = accepted_fd = accept(sep->se_fd, NULL, NULL);
|
---|
1249 | dbg("accepted_fd:%d\n", accepted_fd);
|
---|
1250 | if (ctrl < 0) {
|
---|
1251 | if (errno != EINTR)
|
---|
1252 | bb_perror_msg("accept (for %s)", sep->se_service);
|
---|
1253 | continue;
|
---|
1254 | }
|
---|
1255 | }
|
---|
1256 | /* "nowait" udp */
|
---|
1257 | if (sep->se_socktype == SOCK_DGRAM
|
---|
1258 | && sep->se_family != AF_UNIX
|
---|
1259 | ) {
|
---|
1260 | /* How udp "nowait" works:
|
---|
1261 | * child peeks at (received and buffered by kernel) UDP packet,
|
---|
1262 | * performs connect() on the socket so that it is linked only
|
---|
1263 | * to this peer. But this also affects parent, because descriptors
|
---|
1264 | * are shared after fork() a-la dup(). When parent performs
|
---|
1265 | * select(), it will see this descriptor connected to the peer (!)
|
---|
1266 | * and still readable, will act on it and mess things up
|
---|
1267 | * (can create many copies of same child, etc).
|
---|
1268 | * Parent must create and use new socket instead. */
|
---|
1269 | new_udp_fd = socket(sep->se_family, SOCK_DGRAM, 0);
|
---|
1270 | dbg("new_udp_fd:%d\n", new_udp_fd);
|
---|
1271 | if (new_udp_fd < 0) { /* error: eat packet, forget about it */
|
---|
1272 | udp_err:
|
---|
1273 | recv(sep->se_fd, line, LINE_SIZE, MSG_DONTWAIT);
|
---|
1274 | continue;
|
---|
1275 | }
|
---|
1276 | setsockopt_reuseaddr(new_udp_fd);
|
---|
1277 | /* TODO: better do bind after fork in parent,
|
---|
1278 | * so that we don't have two wildcard bound sockets
|
---|
1279 | * even for a brief moment? */
|
---|
1280 | if (bind(new_udp_fd, &sep->se_lsa->u.sa, sep->se_lsa->len) < 0) {
|
---|
1281 | dbg("bind(new_udp_fd) failed\n");
|
---|
1282 | close(new_udp_fd);
|
---|
1283 | goto udp_err;
|
---|
1284 | }
|
---|
1285 | dbg("bind(new_udp_fd) succeeded\n");
|
---|
1286 | }
|
---|
1287 | }
|
---|
1288 |
|
---|
1289 | block_CHLD_HUP_ALRM(&omask);
|
---|
1290 | pid = 0;
|
---|
1291 | #ifdef INETD_BUILTINS_ENABLED
|
---|
1292 | /* do we need to fork? */
|
---|
1293 | if (sep->se_builtin == NULL
|
---|
1294 | || (sep->se_socktype == SOCK_STREAM
|
---|
1295 | && sep->se_builtin->bi_fork))
|
---|
1296 | #endif
|
---|
1297 | {
|
---|
1298 | if (sep->se_max != 0) {
|
---|
1299 | if (++sep->se_count == 1)
|
---|
1300 | sep->se_time = monotonic_sec();
|
---|
1301 | else if (sep->se_count >= sep->se_max) {
|
---|
1302 | unsigned now = monotonic_sec();
|
---|
1303 | /* did we accumulate se_max connects too quickly? */
|
---|
1304 | if (now - sep->se_time <= CNT_INTERVAL) {
|
---|
1305 | bb_error_msg("%s/%s: too many connections, pausing",
|
---|
1306 | sep->se_service, sep->se_proto);
|
---|
1307 | remove_fd_from_set(sep->se_fd);
|
---|
1308 | close(sep->se_fd);
|
---|
1309 | sep->se_fd = -1;
|
---|
1310 | sep->se_count = 0;
|
---|
1311 | rearm_alarm(); /* will revive it in RETRYTIME sec */
|
---|
1312 | restore_sigmask(&omask);
|
---|
1313 | maybe_close(new_udp_fd);
|
---|
1314 | maybe_close(accepted_fd);
|
---|
1315 | continue; /* -> check next fd in fd set */
|
---|
1316 | }
|
---|
1317 | sep->se_count = 0;
|
---|
1318 | }
|
---|
1319 | }
|
---|
1320 | /* on NOMMU, streamed chargen
|
---|
1321 | * builtin wouldn't work, but it is
|
---|
1322 | * not allowed on NOMMU (ifdefed out) */
|
---|
1323 | #ifdef INETD_BUILTINS_ENABLED
|
---|
1324 | if (BB_MMU && sep->se_builtin)
|
---|
1325 | pid = fork();
|
---|
1326 | else
|
---|
1327 | #endif
|
---|
1328 | pid = vfork();
|
---|
1329 |
|
---|
1330 | if (pid < 0) { /* fork error */
|
---|
1331 | bb_perror_msg("vfork"+1);
|
---|
1332 | sleep(1);
|
---|
1333 | restore_sigmask(&omask);
|
---|
1334 | maybe_close(new_udp_fd);
|
---|
1335 | maybe_close(accepted_fd);
|
---|
1336 | continue; /* -> check next fd in fd set */
|
---|
1337 | }
|
---|
1338 | if (pid == 0)
|
---|
1339 | pid--; /* -1: "we did fork and we are child" */
|
---|
1340 | }
|
---|
1341 | /* if pid == 0 here, we didn't fork */
|
---|
1342 |
|
---|
1343 | if (pid > 0) { /* parent */
|
---|
1344 | if (sep->se_wait) {
|
---|
1345 | /* wait: we passed socket to child,
|
---|
1346 | * will wait for child to terminate */
|
---|
1347 | sep->se_wait = pid;
|
---|
1348 | remove_fd_from_set(sep->se_fd);
|
---|
1349 | }
|
---|
1350 | if (new_udp_fd >= 0) {
|
---|
1351 | /* udp nowait: child connected the socket,
|
---|
1352 | * we created and will use new, unconnected one */
|
---|
1353 | xmove_fd(new_udp_fd, sep->se_fd);
|
---|
1354 | dbg("moved new_udp_fd:%d to sep->se_fd:%d\n", new_udp_fd, sep->se_fd);
|
---|
1355 | }
|
---|
1356 | restore_sigmask(&omask);
|
---|
1357 | maybe_close(accepted_fd);
|
---|
1358 | continue; /* -> check next fd in fd set */
|
---|
1359 | }
|
---|
1360 |
|
---|
1361 | /* we are either child or didn't fork at all */
|
---|
1362 | #ifdef INETD_BUILTINS_ENABLED
|
---|
1363 | if (sep->se_builtin) {
|
---|
1364 | if (pid) { /* "pid" is -1: we did fork */
|
---|
1365 | close(sep->se_fd); /* listening socket */
|
---|
1366 | dbg("closed sep->se_fd:%d\n", sep->se_fd);
|
---|
1367 | logmode = LOGMODE_NONE; /* make xwrite etc silent */
|
---|
1368 | }
|
---|
1369 | restore_sigmask(&omask);
|
---|
1370 | if (sep->se_socktype == SOCK_STREAM)
|
---|
1371 | sep->se_builtin->bi_stream_fn(ctrl, sep);
|
---|
1372 | else
|
---|
1373 | sep->se_builtin->bi_dgram_fn(ctrl, sep);
|
---|
1374 | if (pid) /* we did fork */
|
---|
1375 | _exit(EXIT_FAILURE);
|
---|
1376 | maybe_close(accepted_fd);
|
---|
1377 | continue; /* -> check next fd in fd set */
|
---|
1378 | }
|
---|
1379 | #endif
|
---|
1380 | /* child */
|
---|
1381 | setsid();
|
---|
1382 | /* "nowait" udp */
|
---|
1383 | if (new_udp_fd >= 0) {
|
---|
1384 | len_and_sockaddr *lsa;
|
---|
1385 | int r;
|
---|
1386 |
|
---|
1387 | close(new_udp_fd);
|
---|
1388 | dbg("closed new_udp_fd:%d\n", new_udp_fd);
|
---|
1389 | lsa = xzalloc_lsa(sep->se_family);
|
---|
1390 | /* peek at the packet and remember peer addr */
|
---|
1391 | r = recvfrom(ctrl, NULL, 0, MSG_PEEK|MSG_DONTWAIT,
|
---|
1392 | &lsa->u.sa, &lsa->len);
|
---|
1393 | if (r < 0)
|
---|
1394 | goto do_exit1;
|
---|
1395 | /* make this socket "connected" to peer addr:
|
---|
1396 | * only packets from this peer will be recv'ed,
|
---|
1397 | * and bare write()/send() will work on it */
|
---|
1398 | connect(ctrl, &lsa->u.sa, lsa->len);
|
---|
1399 | dbg("connected ctrl:%d to remote peer\n", ctrl);
|
---|
1400 | free(lsa);
|
---|
1401 | }
|
---|
1402 | /* prepare env and exec program */
|
---|
1403 | pwd = getpwnam(sep->se_user);
|
---|
1404 | if (pwd == NULL) {
|
---|
1405 | bb_error_msg("%s: no such %s", sep->se_user, "user");
|
---|
1406 | goto do_exit1;
|
---|
1407 | }
|
---|
1408 | if (sep->se_group && (grp = getgrnam(sep->se_group)) == NULL) {
|
---|
1409 | bb_error_msg("%s: no such %s", sep->se_group, "group");
|
---|
1410 | goto do_exit1;
|
---|
1411 | }
|
---|
1412 | if (real_uid != 0 && real_uid != pwd->pw_uid) {
|
---|
1413 | /* a user running private inetd */
|
---|
1414 | bb_error_msg("non-root must run services as himself");
|
---|
1415 | goto do_exit1;
|
---|
1416 | }
|
---|
1417 | if (pwd->pw_uid != 0) {
|
---|
1418 | if (sep->se_group)
|
---|
1419 | pwd->pw_gid = grp->gr_gid;
|
---|
1420 | /* initgroups, setgid, setuid: */
|
---|
1421 | change_identity(pwd);
|
---|
1422 | } else if (sep->se_group) {
|
---|
1423 | xsetgid(grp->gr_gid);
|
---|
1424 | setgroups(1, &grp->gr_gid);
|
---|
1425 | }
|
---|
1426 | if (rlim_ofile.rlim_cur != rlim_ofile_cur)
|
---|
1427 | if (setrlimit(RLIMIT_NOFILE, &rlim_ofile) < 0)
|
---|
1428 | bb_perror_msg("setrlimit");
|
---|
1429 |
|
---|
1430 | /* closelog(); - WRONG. we are after vfork,
|
---|
1431 | * this may confuse syslog() internal state.
|
---|
1432 | * Let's hope libc sets syslog fd to CLOEXEC...
|
---|
1433 | */
|
---|
1434 | xmove_fd(ctrl, STDIN_FILENO);
|
---|
1435 | xdup2(STDIN_FILENO, STDOUT_FILENO);
|
---|
1436 | dbg("moved ctrl:%d to fd 0,1[,2]\n", ctrl);
|
---|
1437 | /* manpages of inetd I managed to find either say
|
---|
1438 | * that stderr is also redirected to the network,
|
---|
1439 | * or do not talk about redirection at all (!) */
|
---|
1440 | if (!sep->se_wait) /* only for usual "tcp nowait" */
|
---|
1441 | xdup2(STDIN_FILENO, STDERR_FILENO);
|
---|
1442 | /* NB: among others, this loop closes listening sockets
|
---|
1443 | * for nowait stream children */
|
---|
1444 | for (sep2 = serv_list; sep2; sep2 = sep2->se_next)
|
---|
1445 | if (sep2->se_fd != ctrl)
|
---|
1446 | maybe_close(sep2->se_fd);
|
---|
1447 | sigaction_set(SIGPIPE, &saved_pipe_handler);
|
---|
1448 | restore_sigmask(&omask);
|
---|
1449 | dbg("execing:'%s'\n", sep->se_program);
|
---|
1450 | BB_EXECVP(sep->se_program, sep->se_argv);
|
---|
1451 | bb_perror_msg("can't execute '%s'", sep->se_program);
|
---|
1452 | do_exit1:
|
---|
1453 | /* eat packet in udp case */
|
---|
1454 | if (sep->se_socktype != SOCK_STREAM)
|
---|
1455 | recv(0, line, LINE_SIZE, MSG_DONTWAIT);
|
---|
1456 | _exit(EXIT_FAILURE);
|
---|
1457 | } /* for (sep = servtab...) */
|
---|
1458 | } /* for (;;) */
|
---|
1459 | }
|
---|
1460 |
|
---|
1461 | #if !BB_MMU
|
---|
1462 | static const char *const cat_args[] = { "cat", NULL };
|
---|
1463 | #endif
|
---|
1464 |
|
---|
1465 | /*
|
---|
1466 | * Internet services provided internally by inetd:
|
---|
1467 | */
|
---|
1468 | #if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_ECHO
|
---|
1469 | /* Echo service -- echo data back. */
|
---|
1470 | /* ARGSUSED */
|
---|
1471 | static void FAST_FUNC echo_stream(int s, servtab_t *sep UNUSED_PARAM)
|
---|
1472 | {
|
---|
1473 | #if BB_MMU
|
---|
1474 | while (1) {
|
---|
1475 | ssize_t sz = safe_read(s, line, LINE_SIZE);
|
---|
1476 | if (sz <= 0)
|
---|
1477 | break;
|
---|
1478 | xwrite(s, line, sz);
|
---|
1479 | }
|
---|
1480 | #else
|
---|
1481 | /* We are after vfork here! */
|
---|
1482 | /* move network socket to stdin/stdout */
|
---|
1483 | xmove_fd(s, STDIN_FILENO);
|
---|
1484 | xdup2(STDIN_FILENO, STDOUT_FILENO);
|
---|
1485 | /* no error messages please... */
|
---|
1486 | close(STDERR_FILENO);
|
---|
1487 | xopen(bb_dev_null, O_WRONLY);
|
---|
1488 | BB_EXECVP("cat", (char**)cat_args);
|
---|
1489 | /* on failure we return to main, which does exit(EXIT_FAILURE) */
|
---|
1490 | #endif
|
---|
1491 | }
|
---|
1492 | static void FAST_FUNC echo_dg(int s, servtab_t *sep)
|
---|
1493 | {
|
---|
1494 | enum { BUFSIZE = 12*1024 }; /* for jumbo sized packets! :) */
|
---|
1495 | char *buf = xmalloc(BUFSIZE); /* too big for stack */
|
---|
1496 | int sz;
|
---|
1497 | len_and_sockaddr *lsa = alloca(LSA_LEN_SIZE + sep->se_lsa->len);
|
---|
1498 |
|
---|
1499 | lsa->len = sep->se_lsa->len;
|
---|
1500 | /* dgram builtins are non-forking - DONT BLOCK! */
|
---|
1501 | sz = recvfrom(s, buf, BUFSIZE, MSG_DONTWAIT, &lsa->u.sa, &lsa->len);
|
---|
1502 | if (sz > 0)
|
---|
1503 | sendto(s, buf, sz, 0, &lsa->u.sa, lsa->len);
|
---|
1504 | free(buf);
|
---|
1505 | }
|
---|
1506 | #endif /* FEATURE_INETD_SUPPORT_BUILTIN_ECHO */
|
---|
1507 |
|
---|
1508 |
|
---|
1509 | #if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_DISCARD
|
---|
1510 | /* Discard service -- ignore data. */
|
---|
1511 | /* ARGSUSED */
|
---|
1512 | static void FAST_FUNC discard_stream(int s, servtab_t *sep UNUSED_PARAM)
|
---|
1513 | {
|
---|
1514 | #if BB_MMU
|
---|
1515 | while (safe_read(s, line, LINE_SIZE) > 0)
|
---|
1516 | continue;
|
---|
1517 | #else
|
---|
1518 | /* We are after vfork here! */
|
---|
1519 | /* move network socket to stdin */
|
---|
1520 | xmove_fd(s, STDIN_FILENO);
|
---|
1521 | /* discard output */
|
---|
1522 | close(STDOUT_FILENO);
|
---|
1523 | xopen(bb_dev_null, O_WRONLY);
|
---|
1524 | /* no error messages please... */
|
---|
1525 | xdup2(STDOUT_FILENO, STDERR_FILENO);
|
---|
1526 | BB_EXECVP("cat", (char**)cat_args);
|
---|
1527 | /* on failure we return to main, which does exit(EXIT_FAILURE) */
|
---|
1528 | #endif
|
---|
1529 | }
|
---|
1530 | /* ARGSUSED */
|
---|
1531 | static void FAST_FUNC discard_dg(int s, servtab_t *sep UNUSED_PARAM)
|
---|
1532 | {
|
---|
1533 | /* dgram builtins are non-forking - DONT BLOCK! */
|
---|
1534 | recv(s, line, LINE_SIZE, MSG_DONTWAIT);
|
---|
1535 | }
|
---|
1536 | #endif /* FEATURE_INETD_SUPPORT_BUILTIN_DISCARD */
|
---|
1537 |
|
---|
1538 |
|
---|
1539 | #if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_CHARGEN
|
---|
1540 | #define LINESIZ 72
|
---|
1541 | static void init_ring(void)
|
---|
1542 | {
|
---|
1543 | int i;
|
---|
1544 |
|
---|
1545 | end_ring = ring;
|
---|
1546 | for (i = ' '; i < 127; i++)
|
---|
1547 | *end_ring++ = i;
|
---|
1548 | }
|
---|
1549 | /* Character generator. MMU arches only. */
|
---|
1550 | /* ARGSUSED */
|
---|
1551 | static void FAST_FUNC chargen_stream(int s, servtab_t *sep UNUSED_PARAM)
|
---|
1552 | {
|
---|
1553 | char *rs;
|
---|
1554 | int len;
|
---|
1555 | char text[LINESIZ + 2];
|
---|
1556 |
|
---|
1557 | if (!end_ring) {
|
---|
1558 | init_ring();
|
---|
1559 | rs = ring;
|
---|
1560 | }
|
---|
1561 |
|
---|
1562 | text[LINESIZ] = '\r';
|
---|
1563 | text[LINESIZ + 1] = '\n';
|
---|
1564 | rs = ring;
|
---|
1565 | for (;;) {
|
---|
1566 | len = end_ring - rs;
|
---|
1567 | if (len >= LINESIZ)
|
---|
1568 | memmove(text, rs, LINESIZ);
|
---|
1569 | else {
|
---|
1570 | memmove(text, rs, len);
|
---|
1571 | memmove(text + len, ring, LINESIZ - len);
|
---|
1572 | }
|
---|
1573 | if (++rs == end_ring)
|
---|
1574 | rs = ring;
|
---|
1575 | xwrite(s, text, sizeof(text));
|
---|
1576 | }
|
---|
1577 | }
|
---|
1578 | /* ARGSUSED */
|
---|
1579 | static void FAST_FUNC chargen_dg(int s, servtab_t *sep)
|
---|
1580 | {
|
---|
1581 | int len;
|
---|
1582 | char text[LINESIZ + 2];
|
---|
1583 | len_and_sockaddr *lsa = alloca(LSA_LEN_SIZE + sep->se_lsa->len);
|
---|
1584 |
|
---|
1585 | /* Eat UDP packet which started it all */
|
---|
1586 | /* dgram builtins are non-forking - DONT BLOCK! */
|
---|
1587 | lsa->len = sep->se_lsa->len;
|
---|
1588 | if (recvfrom(s, text, sizeof(text), MSG_DONTWAIT, &lsa->u.sa, &lsa->len) < 0)
|
---|
1589 | return;
|
---|
1590 |
|
---|
1591 | if (!end_ring) {
|
---|
1592 | init_ring();
|
---|
1593 | ring_pos = ring;
|
---|
1594 | }
|
---|
1595 |
|
---|
1596 | len = end_ring - ring_pos;
|
---|
1597 | if (len >= LINESIZ)
|
---|
1598 | memmove(text, ring_pos, LINESIZ);
|
---|
1599 | else {
|
---|
1600 | memmove(text, ring_pos, len);
|
---|
1601 | memmove(text + len, ring, LINESIZ - len);
|
---|
1602 | }
|
---|
1603 | if (++ring_pos == end_ring)
|
---|
1604 | ring_pos = ring;
|
---|
1605 | text[LINESIZ] = '\r';
|
---|
1606 | text[LINESIZ + 1] = '\n';
|
---|
1607 | sendto(s, text, sizeof(text), 0, &lsa->u.sa, lsa->len);
|
---|
1608 | }
|
---|
1609 | #endif /* FEATURE_INETD_SUPPORT_BUILTIN_CHARGEN */
|
---|
1610 |
|
---|
1611 |
|
---|
1612 | #if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_TIME
|
---|
1613 | /*
|
---|
1614 | * Return a machine readable date and time, in the form of the
|
---|
1615 | * number of seconds since midnight, Jan 1, 1900. Since gettimeofday
|
---|
1616 | * returns the number of seconds since midnight, Jan 1, 1970,
|
---|
1617 | * we must add 2208988800 seconds to this figure to make up for
|
---|
1618 | * some seventy years Bell Labs was asleep.
|
---|
1619 | */
|
---|
1620 | static uint32_t machtime(void)
|
---|
1621 | {
|
---|
1622 | struct timeval tv;
|
---|
1623 |
|
---|
1624 | gettimeofday(&tv, NULL);
|
---|
1625 | return htonl((uint32_t)(tv.tv_sec + 2208988800));
|
---|
1626 | }
|
---|
1627 | /* ARGSUSED */
|
---|
1628 | static void FAST_FUNC machtime_stream(int s, servtab_t *sep UNUSED_PARAM)
|
---|
1629 | {
|
---|
1630 | uint32_t result;
|
---|
1631 |
|
---|
1632 | result = machtime();
|
---|
1633 | full_write(s, &result, sizeof(result));
|
---|
1634 | }
|
---|
1635 | static void FAST_FUNC machtime_dg(int s, servtab_t *sep)
|
---|
1636 | {
|
---|
1637 | uint32_t result;
|
---|
1638 | len_and_sockaddr *lsa = alloca(LSA_LEN_SIZE + sep->se_lsa->len);
|
---|
1639 |
|
---|
1640 | lsa->len = sep->se_lsa->len;
|
---|
1641 | if (recvfrom(s, line, LINE_SIZE, MSG_DONTWAIT, &lsa->u.sa, &lsa->len) < 0)
|
---|
1642 | return;
|
---|
1643 |
|
---|
1644 | result = machtime();
|
---|
1645 | sendto(s, &result, sizeof(result), 0, &lsa->u.sa, lsa->len);
|
---|
1646 | }
|
---|
1647 | #endif /* FEATURE_INETD_SUPPORT_BUILTIN_TIME */
|
---|
1648 |
|
---|
1649 |
|
---|
1650 | #if ENABLE_FEATURE_INETD_SUPPORT_BUILTIN_DAYTIME
|
---|
1651 | /* Return human-readable time of day */
|
---|
1652 | /* ARGSUSED */
|
---|
1653 | static void FAST_FUNC daytime_stream(int s, servtab_t *sep UNUSED_PARAM)
|
---|
1654 | {
|
---|
1655 | time_t t;
|
---|
1656 |
|
---|
1657 | t = time(NULL);
|
---|
1658 | fdprintf(s, "%.24s\r\n", ctime(&t));
|
---|
1659 | }
|
---|
1660 | static void FAST_FUNC daytime_dg(int s, servtab_t *sep)
|
---|
1661 | {
|
---|
1662 | time_t t;
|
---|
1663 | len_and_sockaddr *lsa = alloca(LSA_LEN_SIZE + sep->se_lsa->len);
|
---|
1664 |
|
---|
1665 | lsa->len = sep->se_lsa->len;
|
---|
1666 | if (recvfrom(s, line, LINE_SIZE, MSG_DONTWAIT, &lsa->u.sa, &lsa->len) < 0)
|
---|
1667 | return;
|
---|
1668 |
|
---|
1669 | t = time(NULL);
|
---|
1670 | sprintf(line, "%.24s\r\n", ctime(&t));
|
---|
1671 | sendto(s, line, strlen(line), 0, &lsa->u.sa, lsa->len);
|
---|
1672 | }
|
---|
1673 | #endif /* FEATURE_INETD_SUPPORT_BUILTIN_DAYTIME */
|
---|