xref: /freebsd/crypto/heimdal/lib/roken/mini_inetd.c (revision 1669d8afc64812c8d2d1d147ae1fd42ff441e1b1)
1 /*
2  * Copyright (c) 1995 - 2001 Kungliga Tekniska H�gskolan
3  * (Royal Institute of Technology, Stockholm, Sweden).
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  *
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  *
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * 3. Neither the name of the Institute nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 #ifdef HAVE_CONFIG_H
35 #include <config.h>
36 RCSID("$Id: mini_inetd.c,v 1.30 2002/02/18 19:08:55 joda Exp $");
37 #endif
38 
39 #include <err.h>
40 #include "roken.h"
41 
42 /*
43  * accept a connection on `s' and pretend it's served by inetd.
44  */
45 
46 static void
47 accept_it (int s)
48 {
49     int s2;
50 
51     s2 = accept(s, NULL, NULL);
52     if(s2 < 0)
53 	err (1, "accept");
54     close(s);
55     dup2(s2, STDIN_FILENO);
56     dup2(s2, STDOUT_FILENO);
57     /* dup2(s2, STDERR_FILENO); */
58     close(s2);
59 }
60 
61 /*
62  * Listen on a specified port, emulating inetd.
63  */
64 
65 void
66 mini_inetd_addrinfo (struct addrinfo *ai)
67 {
68     int ret;
69     struct addrinfo *a;
70     int n, nalloc, i;
71     int *fds;
72     fd_set orig_read_set, read_set;
73     int max_fd = -1;
74 
75     for (nalloc = 0, a = ai; a != NULL; a = a->ai_next)
76 	++nalloc;
77 
78     fds = malloc (nalloc * sizeof(*fds));
79     if (fds == NULL)
80 	errx (1, "mini_inetd: out of memory");
81 
82     FD_ZERO(&orig_read_set);
83 
84     for (i = 0, a = ai; a != NULL; a = a->ai_next) {
85 	fds[i] = socket (a->ai_family, a->ai_socktype, a->ai_protocol);
86 	if (fds[i] < 0) {
87 	    warn ("socket af = %d", a->ai_family);
88 	    continue;
89 	}
90 	socket_set_reuseaddr (fds[i], 1);
91 	if (bind (fds[i], a->ai_addr, a->ai_addrlen) < 0) {
92 	    warn ("bind af = %d", a->ai_family);
93 	    close(fds[i]);
94 	    continue;
95 	}
96 	if (listen (fds[i], SOMAXCONN) < 0) {
97 	    warn ("listen af = %d", a->ai_family);
98 	    close(fds[i]);
99 	    continue;
100 	}
101 	if (fds[i] >= FD_SETSIZE)
102 	    errx (1, "fd too large");
103 	FD_SET(fds[i], &orig_read_set);
104 	max_fd = max(max_fd, fds[i]);
105 	++i;
106     }
107     if (i == 0)
108 	errx (1, "no sockets");
109     n = i;
110 
111     do {
112 	read_set = orig_read_set;
113 
114 	ret = select (max_fd + 1, &read_set, NULL, NULL, NULL);
115 	if (ret < 0 && errno != EINTR)
116 	    err (1, "select");
117     } while (ret <= 0);
118 
119     for (i = 0; i < n; ++i)
120 	if (FD_ISSET (fds[i], &read_set)) {
121 	    accept_it (fds[i]);
122 	    return;
123 	}
124     abort ();
125 }
126 
127 void
128 mini_inetd (int port)
129 {
130     int error;
131     struct addrinfo *ai, hints;
132     char portstr[NI_MAXSERV];
133 
134     memset (&hints, 0, sizeof(hints));
135     hints.ai_flags    = AI_PASSIVE;
136     hints.ai_socktype = SOCK_STREAM;
137     hints.ai_family   = PF_UNSPEC;
138 
139     snprintf (portstr, sizeof(portstr), "%d", ntohs(port));
140 
141     error = getaddrinfo (NULL, portstr, &hints, &ai);
142     if (error)
143 	errx (1, "getaddrinfo: %s", gai_strerror (error));
144 
145     mini_inetd_addrinfo(ai);
146 
147     freeaddrinfo(ai);
148 }
149