1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
|
/* $OpenBSD: bindresvport.c,v 1.17 2005/12/21 01:40:22 millert Exp $ */
/*
* Copyright 1996, Jason Downs. All rights reserved.
* Copyright 1998, Theo de Raadt. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <errno.h>
#include <string.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
/*
* Bind a socket to a privileged IP port
*/
int
bindresvport(int sd, struct sockaddr_in *sin)
{
return bindresvport_sa(sd, (struct sockaddr *)sin);
}
/*
* Bind a socket to a privileged port for whatever protocol.
*/
int
bindresvport_sa(int sd, struct sockaddr *sa)
{
int old, error, af;
struct sockaddr_storage myaddr;
struct sockaddr_in *sin;
struct sockaddr_in6 *sin6;
int proto, portrange, portlow;
u_int16_t port;
socklen_t salen;
if (sa == NULL) {
salen = sizeof(myaddr);
sa = (struct sockaddr *)&myaddr;
if (getsockname(sd, sa, &salen) == -1)
return -1; /* errno is correctly set */
af = sa->sa_family;
memset(&myaddr, 0, salen);
} else
af = sa->sa_family;
if (af == AF_INET) {
proto = IPPROTO_IP;
portrange = IP_PORTRANGE;
portlow = IP_PORTRANGE_LOW;
sin = (struct sockaddr_in *)sa;
salen = sizeof(struct sockaddr_in);
port = sin->sin_port;
} else if (af == AF_INET6) {
proto = IPPROTO_IPV6;
portrange = IPV6_PORTRANGE;
portlow = IPV6_PORTRANGE_LOW;
sin6 = (struct sockaddr_in6 *)sa;
salen = sizeof(struct sockaddr_in6);
port = sin6->sin6_port;
} else {
errno = EPFNOSUPPORT;
return (-1);
}
sa->sa_family = af;
sa->sa_len = salen;
if (port == 0) {
socklen_t oldlen = sizeof(old);
error = getsockopt(sd, proto, portrange, &old, &oldlen);
if (error < 0)
return (error);
error = setsockopt(sd, proto, portrange, &portlow,
sizeof(portlow));
if (error < 0)
return (error);
}
error = bind(sd, sa, salen);
if (port == 0) {
int saved_errno = errno;
if (error) {
if (setsockopt(sd, proto, portrange, &old,
sizeof(old)) < 0)
errno = saved_errno;
return (error);
}
if (sa != (struct sockaddr *)&myaddr) {
/* Hmm, what did the kernel assign... */
if (getsockname(sd, sa, &salen) < 0)
errno = saved_errno;
return (error);
}
}
return (error);
}
|
