xref: /netbsd-src/sys/kern/sys_socket.c (revision b2a8932dbe9fdfd3d41d60d0a04b9a3ba294763d)
1 /*	$NetBSD: sys_socket.c,v 1.76 2017/11/30 20:25:55 christos Exp $	*/
2 
3 /*-
4  * Copyright (c) 2008, 2009 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Andrew Doran.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 /*
33  * Copyright (c) 1982, 1986, 1990, 1993
34  *	The Regents of the University of California.  All rights reserved.
35  *
36  * Redistribution and use in source and binary forms, with or without
37  * modification, are permitted provided that the following conditions
38  * are met:
39  * 1. Redistributions of source code must retain the above copyright
40  *    notice, this list of conditions and the following disclaimer.
41  * 2. Redistributions in binary form must reproduce the above copyright
42  *    notice, this list of conditions and the following disclaimer in the
43  *    documentation and/or other materials provided with the distribution.
44  * 3. Neither the name of the University nor the names of its contributors
45  *    may be used to endorse or promote products derived from this software
46  *    without specific prior written permission.
47  *
48  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
49  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
50  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
51  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
52  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
53  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
54  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
55  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
56  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
57  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
58  * SUCH DAMAGE.
59  *
60  *	@(#)sys_socket.c	8.3 (Berkeley) 2/14/95
61  */
62 
63 #include <sys/cdefs.h>
64 __KERNEL_RCSID(0, "$NetBSD: sys_socket.c,v 1.76 2017/11/30 20:25:55 christos Exp $");
65 
66 #include <sys/param.h>
67 #include <sys/systm.h>
68 #include <sys/systm.h>
69 #include <sys/file.h>
70 #include <sys/mbuf.h>
71 #include <sys/protosw.h>
72 #include <sys/socket.h>
73 #include <sys/socketvar.h>
74 #include <sys/ioctl.h>
75 #include <sys/stat.h>
76 #include <sys/poll.h>
77 #include <sys/proc.h>
78 #include <sys/kauth.h>
79 
80 #include <net/if.h>
81 #include <net/route.h>
82 
83 const struct fileops socketops = {
84 	.fo_name = "socket",
85 	.fo_read = soo_read,
86 	.fo_write = soo_write,
87 	.fo_ioctl = soo_ioctl,
88 	.fo_fcntl = soo_fcntl,
89 	.fo_poll = soo_poll,
90 	.fo_stat = soo_stat,
91 	.fo_close = soo_close,
92 	.fo_kqfilter = soo_kqfilter,
93 	.fo_restart = soo_restart,
94 };
95 
96 int (*ifioctl)(struct socket *, u_long, void *, struct lwp *) = (void *)eopnotsupp;
97 
98 /* ARGSUSED */
99 int
100 soo_read(file_t *fp, off_t *offset, struct uio *uio, kauth_cred_t cred,
101 	 int flags)
102 {
103 	struct socket *so = fp->f_socket;
104 	int error;
105 
106 	error = (*so->so_receive)(so, NULL, uio, NULL, NULL, NULL);
107 
108 	return error;
109 }
110 
111 /* ARGSUSED */
112 int
113 soo_write(file_t *fp, off_t *offset, struct uio *uio, kauth_cred_t cred,
114 	  int flags)
115 {
116 	struct socket *so = fp->f_socket;
117 	int error;
118 
119 	error = (*so->so_send)(so, NULL, uio, NULL, NULL, 0, curlwp);
120 
121 	return error;
122 }
123 
124 int
125 soo_ioctl(file_t *fp, u_long cmd, void *data)
126 {
127 	struct socket *so = fp->f_socket;
128 	int error = 0;
129 
130 	switch (cmd) {
131 
132 	case FIONBIO:
133 		solock(so);
134 		if (*(int *)data)
135 			so->so_state |= SS_NBIO;
136 		else
137 			so->so_state &= ~SS_NBIO;
138 		sounlock(so);
139 		break;
140 
141 	case FIOASYNC:
142 		solock(so);
143 		if (*(int *)data) {
144 			so->so_state |= SS_ASYNC;
145 			so->so_rcv.sb_flags |= SB_ASYNC;
146 			so->so_snd.sb_flags |= SB_ASYNC;
147 		} else {
148 			so->so_state &= ~SS_ASYNC;
149 			so->so_rcv.sb_flags &= ~SB_ASYNC;
150 			so->so_snd.sb_flags &= ~SB_ASYNC;
151 		}
152 		sounlock(so);
153 		break;
154 
155 	case FIONREAD:
156 		*(int *)data = so->so_rcv.sb_cc;
157 		break;
158 
159 	case FIONWRITE:
160 		*(int *)data = so->so_snd.sb_cc;
161 		break;
162 
163 	case FIONSPACE:
164 		/*
165 		 * See the comment around sbspace()'s definition
166 		 * in sys/socketvar.h in face of counts about maximum
167 		 * to understand the following test. We detect overflow
168 		 * and return zero.
169 		 */
170 		solock(so);
171 		if ((so->so_snd.sb_hiwat < so->so_snd.sb_cc)
172 		    || (so->so_snd.sb_mbmax < so->so_snd.sb_mbcnt))
173 			*(int *)data = 0;
174 		else
175 			*(int *)data = sbspace(&so->so_snd);
176 		sounlock(so);
177 		break;
178 
179 	case SIOCSPGRP:
180 	case FIOSETOWN:
181 	case TIOCSPGRP:
182 		error = fsetown(&so->so_pgid, cmd, data);
183 		break;
184 
185 	case SIOCGPGRP:
186 	case FIOGETOWN:
187 	case TIOCGPGRP:
188 		error = fgetown(so->so_pgid, cmd, data);
189 		break;
190 
191 	case SIOCATMARK:
192 		*(int *)data = (so->so_state&SS_RCVATMARK) != 0;
193 		break;
194 
195 	default:
196 		/*
197 		 * Interface/routing/protocol specific ioctls:
198 		 * interface and routing ioctls should have a
199 		 * different entry since a socket's unnecessary
200 		 */
201 		if (IOCGROUP(cmd) == 'i')
202 			/*
203 			 * KERNEL_LOCK will be held later if if_ioctl() of the
204 			 * interface isn't MP-safe.
205 			 */
206 			error = ifioctl(so, cmd, data, curlwp);
207 		else {
208 			KERNEL_LOCK(1, NULL);
209 			error = (*so->so_proto->pr_usrreqs->pr_ioctl)(so,
210 			    cmd, data, NULL);
211 			KERNEL_UNLOCK_ONE(NULL);
212 		}
213 		break;
214 	}
215 
216 
217 	return error;
218 }
219 
220 int
221 soo_fcntl(file_t *fp, u_int cmd, void *data)
222 {
223 
224 	if (cmd == F_SETFL)
225 		return 0;
226 	else
227 		return EOPNOTSUPP;
228 }
229 
230 int
231 soo_poll(file_t *fp, int events)
232 {
233 
234 	return sopoll(fp->f_socket, events);
235 }
236 
237 int
238 soo_stat(file_t *fp, struct stat *ub)
239 {
240 	struct socket *so = fp->f_socket;
241 	int error;
242 
243 	memset(ub, 0, sizeof(*ub));
244 	ub->st_mode = S_IFSOCK;
245 
246 	solock(so);
247 	error = (*so->so_proto->pr_usrreqs->pr_stat)(so, ub);
248 	sounlock(so);
249 
250 	return error;
251 }
252 
253 /* ARGSUSED */
254 int
255 soo_close(file_t *fp)
256 {
257 	int error = 0;
258 
259 	if (fp->f_socket)
260 		error = soclose(fp->f_socket);
261 	fp->f_socket = NULL;
262 
263 	return error;
264 }
265 
266 void
267 soo_restart(file_t *fp)
268 {
269 
270 	sorestart(fp->f_socket);
271 }
272