xref: /netbsd/sys/kern/sys_socket.c (revision 8178a7a2)
1 /*	$NetBSD: sys_socket.c,v 1.81 2023/04/22 13:53:02 riastradh 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 1.81 2023/04/22 13:53:02 riastradh 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 static int soo_fpathconf(struct file *, int, register_t *);
84 static int soo_posix_fadvise(struct file *, off_t, off_t, int);
85 
86 const struct fileops socketops = {
87 	.fo_name = "socket",
88 	.fo_read = soo_read,
89 	.fo_write = soo_write,
90 	.fo_ioctl = soo_ioctl,
91 	.fo_fcntl = fnullop_fcntl,
92 	.fo_poll = soo_poll,
93 	.fo_stat = soo_stat,
94 	.fo_close = soo_close,
95 	.fo_kqfilter = soo_kqfilter,
96 	.fo_restart = soo_restart,
97 	.fo_fpathconf = soo_fpathconf,
98 	.fo_posix_fadvise = soo_posix_fadvise,
99 };
100 
101 int (*ifioctl)(struct socket *, u_long, void *, struct lwp *) = (void *)eopnotsupp;
102 
103 /* ARGSUSED */
104 int
soo_read(file_t * fp,off_t * offset,struct uio * uio,kauth_cred_t cred,int flags)105 soo_read(file_t *fp, off_t *offset, struct uio *uio, kauth_cred_t cred,
106 	 int flags)
107 {
108 	struct socket *so = fp->f_socket;
109 	int error;
110 
111 	error = (*so->so_receive)(so, NULL, uio, NULL, NULL, NULL);
112 
113 	return error;
114 }
115 
116 /* ARGSUSED */
117 int
soo_write(file_t * fp,off_t * offset,struct uio * uio,kauth_cred_t cred,int flags)118 soo_write(file_t *fp, off_t *offset, struct uio *uio, kauth_cred_t cred,
119 	  int flags)
120 {
121 	struct socket *so = fp->f_socket;
122 	int error;
123 
124 	error = (*so->so_send)(so, NULL, uio, NULL, NULL, 0, curlwp);
125 
126 	return error;
127 }
128 
129 int
soo_ioctl(file_t * fp,u_long cmd,void * data)130 soo_ioctl(file_t *fp, u_long cmd, void *data)
131 {
132 	struct socket *so = fp->f_socket;
133 	int error = 0;
134 
135 	switch (cmd) {
136 
137 	case FIONBIO:
138 		solock(so);
139 		if (*(int *)data)
140 			so->so_state |= SS_NBIO;
141 		else
142 			so->so_state &= ~SS_NBIO;
143 		sounlock(so);
144 		break;
145 
146 	case FIOASYNC:
147 		solock(so);
148 		if (*(int *)data) {
149 			so->so_rcv.sb_flags |= SB_ASYNC;
150 			so->so_snd.sb_flags |= SB_ASYNC;
151 		} else {
152 			so->so_rcv.sb_flags &= ~SB_ASYNC;
153 			so->so_snd.sb_flags &= ~SB_ASYNC;
154 		}
155 		sounlock(so);
156 		break;
157 
158 	case FIONREAD:
159 		*(int *)data = so->so_rcv.sb_cc;
160 		break;
161 
162 	case FIONWRITE:
163 		*(int *)data = so->so_snd.sb_cc;
164 		break;
165 
166 	case FIONSPACE:
167 		/*
168 		 * See the comment around sbspace()'s definition
169 		 * in sys/socketvar.h in face of counts about maximum
170 		 * to understand the following test. We detect overflow
171 		 * and return zero.
172 		 */
173 		solock(so);
174 		if ((so->so_snd.sb_hiwat < so->so_snd.sb_cc)
175 		    || (so->so_snd.sb_mbmax < so->so_snd.sb_mbcnt))
176 			*(int *)data = 0;
177 		else
178 			*(int *)data = sbspace(&so->so_snd);
179 		sounlock(so);
180 		break;
181 
182 	case SIOCSPGRP:
183 	case FIOSETOWN:
184 	case TIOCSPGRP:
185 		error = fsetown(&so->so_pgid, cmd, data);
186 		break;
187 
188 	case SIOCGPGRP:
189 	case FIOGETOWN:
190 	case TIOCGPGRP:
191 		error = fgetown(so->so_pgid, cmd, data);
192 		break;
193 
194 	case SIOCATMARK:
195 		*(int *)data = (so->so_state&SS_RCVATMARK) != 0;
196 		break;
197 
198 	case SIOCPEELOFF:
199 		solock(so);
200 		error = do_sys_peeloff(so, data);
201 		sounlock(so);
202 		break;
203 
204 	default:
205 		/*
206 		 * Interface/routing/protocol specific ioctls:
207 		 * interface and routing ioctls should have a
208 		 * different entry since a socket's unnecessary
209 		 */
210 		if (IOCGROUP(cmd) == 'i')
211 			/*
212 			 * KERNEL_LOCK will be held later if if_ioctl() of the
213 			 * interface isn't MP-safe.
214 			 */
215 			error = ifioctl(so, cmd, data, curlwp);
216 		else {
217 			KERNEL_LOCK(1, NULL);
218 			error = (*so->so_proto->pr_usrreqs->pr_ioctl)(so,
219 			    cmd, data, NULL);
220 			KERNEL_UNLOCK_ONE(NULL);
221 		}
222 		break;
223 	}
224 
225 
226 	return error;
227 }
228 
229 int
soo_poll(file_t * fp,int events)230 soo_poll(file_t *fp, int events)
231 {
232 
233 	return sopoll(fp->f_socket, events);
234 }
235 
236 int
soo_stat(file_t * fp,struct stat * ub)237 soo_stat(file_t *fp, struct stat *ub)
238 {
239 	struct socket *so = fp->f_socket;
240 	int error;
241 
242 	memset(ub, 0, sizeof(*ub));
243 	ub->st_mode = S_IFSOCK;
244 
245 	solock(so);
246 	error = (*so->so_proto->pr_usrreqs->pr_stat)(so, ub);
247 	sounlock(so);
248 
249 	return error;
250 }
251 
252 /* ARGSUSED */
253 int
soo_close(file_t * fp)254 soo_close(file_t *fp)
255 {
256 	int error = 0;
257 
258 	if (fp->f_socket)
259 		error = soclose(fp->f_socket);
260 	fp->f_socket = NULL;
261 
262 	return error;
263 }
264 
265 void
soo_restart(file_t * fp)266 soo_restart(file_t *fp)
267 {
268 
269 	sorestart(fp->f_socket);
270 }
271 
272 static int
soo_fpathconf(struct file * fp,int name,register_t * retval)273 soo_fpathconf(struct file *fp, int name, register_t *retval)
274 {
275 
276 	switch (name) {
277 	case _PC_PIPE_BUF:
278 		*retval = PIPE_BUF;
279 		return 0;
280 	default:
281 		return EINVAL;
282 	}
283 }
284 
285 static int
soo_posix_fadvise(struct file * fp,off_t offset,off_t len,int advice)286 soo_posix_fadvise(struct file *fp, off_t offset, off_t len, int advice)
287 {
288 
289 	return ESPIPE;
290 }
291