xref: /openbsd/sys/kern/sys_socket.c (revision d89ec533)
1 /*	$OpenBSD: sys_socket.c,v 1.47 2021/10/24 00:02:25 jsg Exp $	*/
2 /*	$NetBSD: sys_socket.c,v 1.13 1995/08/12 23:59:09 mycroft Exp $	*/
3 
4 /*
5  * Copyright (c) 1982, 1986, 1990, 1993
6  *	The Regents of the University of California.  All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
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  * 3. Neither the name of the University nor the names of its contributors
17  *    may be used to endorse or promote products derived from this software
18  *    without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  *
32  *	@(#)sys_socket.c	8.1 (Berkeley) 6/10/93
33  */
34 
35 #include <sys/param.h>
36 #include <sys/systm.h>
37 #include <sys/file.h>
38 #include <sys/proc.h>
39 #include <sys/mbuf.h>
40 #include <sys/protosw.h>
41 #include <sys/socket.h>
42 #include <sys/socketvar.h>
43 #include <sys/ioctl.h>
44 #include <sys/poll.h>
45 #include <sys/stat.h>
46 #include <sys/fcntl.h>
47 
48 #include <net/if.h>
49 #include <net/route.h>
50 
51 const struct fileops socketops = {
52 	.fo_read	= soo_read,
53 	.fo_write	= soo_write,
54 	.fo_ioctl	= soo_ioctl,
55 	.fo_poll	= soo_poll,
56 	.fo_kqfilter	= soo_kqfilter,
57 	.fo_stat	= soo_stat,
58 	.fo_close	= soo_close
59 };
60 
61 int
62 soo_read(struct file *fp, struct uio *uio, int fflags)
63 {
64 	struct socket *so = (struct socket *)fp->f_data;
65 	int flags = 0;
66 
67 	if (fp->f_flag & FNONBLOCK)
68 		flags |= MSG_DONTWAIT;
69 
70 	return (soreceive(so, NULL, uio, NULL, NULL, &flags, 0));
71 }
72 
73 int
74 soo_write(struct file *fp, struct uio *uio, int fflags)
75 {
76 	struct socket *so = (struct socket *)fp->f_data;
77 	int flags = 0;
78 
79 	if (fp->f_flag & FNONBLOCK)
80 		flags |= MSG_DONTWAIT;
81 
82 	return (sosend(so, NULL, uio, NULL, NULL, flags));
83 }
84 
85 int
86 soo_ioctl(struct file *fp, u_long cmd, caddr_t data, struct proc *p)
87 {
88 	struct socket *so = (struct socket *)fp->f_data;
89 	int s, error = 0;
90 
91 	switch (cmd) {
92 
93 	case FIONBIO:
94 		break;
95 
96 	case FIOASYNC:
97 		s = solock(so);
98 		if (*(int *)data) {
99 			so->so_rcv.sb_flags |= SB_ASYNC;
100 			so->so_snd.sb_flags |= SB_ASYNC;
101 		} else {
102 			so->so_rcv.sb_flags &= ~SB_ASYNC;
103 			so->so_snd.sb_flags &= ~SB_ASYNC;
104 		}
105 		sounlock(so, s);
106 		break;
107 
108 	case FIONREAD:
109 		*(int *)data = so->so_rcv.sb_datacc;
110 		break;
111 
112 	case FIOSETOWN:
113 	case SIOCSPGRP:
114 	case TIOCSPGRP:
115 		error = sigio_setown(&so->so_sigio, cmd, data);
116 		break;
117 
118 	case FIOGETOWN:
119 	case SIOCGPGRP:
120 	case TIOCGPGRP:
121 		sigio_getown(&so->so_sigio, cmd, data);
122 		break;
123 
124 	case SIOCATMARK:
125 		*(int *)data = (so->so_state&SS_RCVATMARK) != 0;
126 		break;
127 
128 	default:
129 		/*
130 		 * Interface/routing/protocol specific ioctls:
131 		 * interface and routing ioctls should have a
132 		 * different entry since a socket's unnecessary
133 		 */
134 		if (IOCGROUP(cmd) == 'i') {
135 			KERNEL_LOCK();
136 			error = ifioctl(so, cmd, data, p);
137 			KERNEL_UNLOCK();
138 			return (error);
139 		}
140 		if (IOCGROUP(cmd) == 'r')
141 			return (EOPNOTSUPP);
142 		KERNEL_LOCK();
143 		error = ((*so->so_proto->pr_usrreq)(so, PRU_CONTROL,
144 		    (struct mbuf *)cmd, (struct mbuf *)data, NULL, p));
145 		KERNEL_UNLOCK();
146 		break;
147 	}
148 
149 	return (error);
150 }
151 
152 int
153 soo_poll(struct file *fp, int events, struct proc *p)
154 {
155 	struct socket *so = fp->f_data;
156 	int revents = 0;
157 	int s;
158 
159 	s = solock(so);
160 	if (events & (POLLIN | POLLRDNORM)) {
161 		if (soreadable(so))
162 			revents |= events & (POLLIN | POLLRDNORM);
163 	}
164 	/* NOTE: POLLHUP and POLLOUT/POLLWRNORM are mutually exclusive */
165 	if (so->so_state & SS_ISDISCONNECTED) {
166 		revents |= POLLHUP;
167 	} else if (events & (POLLOUT | POLLWRNORM)) {
168 		if (sowriteable(so))
169 			revents |= events & (POLLOUT | POLLWRNORM);
170 	}
171 	if (events & (POLLPRI | POLLRDBAND)) {
172 		if (so->so_oobmark || (so->so_state & SS_RCVATMARK))
173 			revents |= events & (POLLPRI | POLLRDBAND);
174 	}
175 	if (revents == 0) {
176 		if (events & (POLLIN | POLLPRI | POLLRDNORM | POLLRDBAND)) {
177 			selrecord(p, &so->so_rcv.sb_sel);
178 			so->so_rcv.sb_flags |= SB_SEL;
179 		}
180 		if (events & (POLLOUT | POLLWRNORM)) {
181 			selrecord(p, &so->so_snd.sb_sel);
182 			so->so_snd.sb_flags |= SB_SEL;
183 		}
184 	}
185 	sounlock(so, s);
186 	return (revents);
187 }
188 
189 int
190 soo_stat(struct file *fp, struct stat *ub, struct proc *p)
191 {
192 	struct socket *so = fp->f_data;
193 	int s;
194 
195 	memset(ub, 0, sizeof (*ub));
196 	ub->st_mode = S_IFSOCK;
197 	s = solock(so);
198 	if ((so->so_state & SS_CANTRCVMORE) == 0 || so->so_rcv.sb_cc != 0)
199 		ub->st_mode |= S_IRUSR | S_IRGRP | S_IROTH;
200 	if ((so->so_state & SS_CANTSENDMORE) == 0)
201 		ub->st_mode |= S_IWUSR | S_IWGRP | S_IWOTH;
202 	ub->st_uid = so->so_euid;
203 	ub->st_gid = so->so_egid;
204 	(void) ((*so->so_proto->pr_usrreq)(so, PRU_SENSE,
205 	    (struct mbuf *)ub, NULL, NULL, p));
206 	sounlock(so, s);
207 	return (0);
208 }
209 
210 int
211 soo_close(struct file *fp, struct proc *p)
212 {
213 	int flags, error = 0;
214 
215 	if (fp->f_data) {
216 		flags = (fp->f_flag & FNONBLOCK) ? MSG_DONTWAIT : 0;
217 		error = soclose(fp->f_data, flags);
218 	}
219 	fp->f_data = NULL;
220 	return (error);
221 }
222