xref: /netbsd-src/sys/kern/sys_socket.c (revision 369bde8f44daf5ad74687d82554eae9c577ea65d)
1 /*	$NetBSD: sys_socket.c,v 1.84 2024/12/06 18:44:00 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 1.84 2024/12/06 18:44:00 riastradh Exp $");
65 
66 #include <sys/param.h>
67 #include <sys/types.h>
68 
69 #include <sys/file.h>
70 #include <sys/ioctl.h>
71 #include <sys/kauth.h>
72 #include <sys/mbuf.h>
73 #include <sys/poll.h>
74 #include <sys/proc.h>
75 #include <sys/protosw.h>
76 #include <sys/sdt.h>
77 #include <sys/socket.h>
78 #include <sys/socketvar.h>
79 #include <sys/stat.h>
80 #include <sys/systm.h>
81 
82 #include <net/if.h>
83 #include <net/route.h>
84 
85 static int soo_fpathconf(struct file *, int, register_t *);
86 static int soo_posix_fadvise(struct file *, off_t, off_t, int);
87 
88 const struct fileops socketops = {
89 	.fo_name = "socket",
90 	.fo_read = soo_read,
91 	.fo_write = soo_write,
92 	.fo_ioctl = soo_ioctl,
93 	.fo_fcntl = fnullop_fcntl,
94 	.fo_poll = soo_poll,
95 	.fo_stat = soo_stat,
96 	.fo_close = soo_close,
97 	.fo_kqfilter = soo_kqfilter,
98 	.fo_restart = soo_restart,
99 	.fo_fpathconf = soo_fpathconf,
100 	.fo_posix_fadvise = soo_posix_fadvise,
101 };
102 
103 int (*ifioctl)(struct socket *, u_long, void *, struct lwp *) = (void *)eopnotsupp;
104 
105 /* ARGSUSED */
106 int
107 soo_read(file_t *fp, off_t *offset, struct uio *uio, kauth_cred_t cred,
108 	 int flags)
109 {
110 	struct socket *so = fp->f_socket;
111 	int error;
112 
113 	error = (*so->so_receive)(so, NULL, uio, NULL, NULL, NULL);
114 
115 	return error;
116 }
117 
118 /* ARGSUSED */
119 int
120 soo_write(file_t *fp, off_t *offset, struct uio *uio, kauth_cred_t cred,
121 	  int flags)
122 {
123 	struct socket *so = fp->f_socket;
124 	int error;
125 
126 	error = (*so->so_send)(so, NULL, uio, NULL, NULL, 0, curlwp);
127 
128 	return error;
129 }
130 
131 int
132 soo_ioctl(file_t *fp, u_long cmd, void *data)
133 {
134 	struct socket *so = fp->f_socket;
135 	int error = 0;
136 
137 	switch (cmd) {
138 
139 	case FIONBIO:
140 		solock(so);
141 		if (*(int *)data)
142 			so->so_state |= SS_NBIO;
143 		else
144 			so->so_state &= ~SS_NBIO;
145 		sounlock(so);
146 		break;
147 
148 	case FIOASYNC:
149 		solock(so);
150 		if (*(int *)data) {
151 			so->so_rcv.sb_flags |= SB_ASYNC;
152 			so->so_snd.sb_flags |= SB_ASYNC;
153 		} else {
154 			so->so_rcv.sb_flags &= ~SB_ASYNC;
155 			so->so_snd.sb_flags &= ~SB_ASYNC;
156 		}
157 		sounlock(so);
158 		break;
159 
160 	case FIONREAD:
161 		*(int *)data = so->so_rcv.sb_cc;
162 		break;
163 
164 	case FIONWRITE:
165 		*(int *)data = so->so_snd.sb_cc;
166 		break;
167 
168 	case FIONSPACE:
169 		/*
170 		 * See the comment around sbspace()'s definition
171 		 * in sys/socketvar.h in face of counts about maximum
172 		 * to understand the following test. We detect overflow
173 		 * and return zero.
174 		 */
175 		solock(so);
176 		if ((so->so_snd.sb_hiwat < so->so_snd.sb_cc)
177 		    || (so->so_snd.sb_mbmax < so->so_snd.sb_mbcnt))
178 			*(int *)data = 0;
179 		else
180 			*(int *)data = sbspace(&so->so_snd);
181 		sounlock(so);
182 		break;
183 
184 	case SIOCSPGRP:
185 	case FIOSETOWN:
186 	case TIOCSPGRP:
187 		error = fsetown(&so->so_pgid, cmd, data);
188 		break;
189 
190 	case SIOCGPGRP:
191 	case FIOGETOWN:
192 	case TIOCGPGRP:
193 		error = fgetown(so->so_pgid, cmd, data);
194 		break;
195 
196 	case SIOCATMARK:
197 		*(int *)data = (so->so_state&SS_RCVATMARK) != 0;
198 		break;
199 
200 	case SIOCPEELOFF:
201 		solock(so);
202 		error = do_sys_peeloff(so, data);
203 		sounlock(so);
204 		break;
205 
206 	default:
207 		/*
208 		 * Interface/routing/protocol specific ioctls:
209 		 * interface and routing ioctls should have a
210 		 * different entry since a socket's unnecessary
211 		 */
212 		if (IOCGROUP(cmd) == 'i')
213 			/*
214 			 * KERNEL_LOCK will be held later if if_ioctl() of the
215 			 * interface isn't MP-safe.
216 			 */
217 			error = ifioctl(so, cmd, data, curlwp);
218 		else {
219 			KERNEL_LOCK(1, NULL);
220 			error = (*so->so_proto->pr_usrreqs->pr_ioctl)(so,
221 			    cmd, data, NULL);
222 			KERNEL_UNLOCK_ONE(NULL);
223 		}
224 		break;
225 	}
226 
227 
228 	return error;
229 }
230 
231 int
232 soo_poll(file_t *fp, int events)
233 {
234 
235 	return sopoll(fp->f_socket, events);
236 }
237 
238 int
239 soo_stat(file_t *fp, struct stat *ub)
240 {
241 	struct socket *so = fp->f_socket;
242 	int error;
243 
244 	memset(ub, 0, sizeof(*ub));
245 	ub->st_mode = S_IFSOCK;
246 
247 	solock(so);
248 	error = (*so->so_proto->pr_usrreqs->pr_stat)(so, ub);
249 	sounlock(so);
250 
251 	return error;
252 }
253 
254 /* ARGSUSED */
255 int
256 soo_close(file_t *fp)
257 {
258 	int error = 0;
259 
260 	if (fp->f_socket)
261 		error = soclose(fp->f_socket);
262 	fp->f_socket = NULL;
263 
264 	return error;
265 }
266 
267 void
268 soo_restart(file_t *fp)
269 {
270 
271 	sorestart(fp->f_socket);
272 }
273 
274 static int
275 soo_fpathconf(struct file *fp, int name, register_t *retval)
276 {
277 
278 	switch (name) {
279 	case _PC_PIPE_BUF:
280 		*retval = PIPE_BUF;
281 		return 0;
282 	default:
283 		return SET_ERROR(EINVAL);
284 	}
285 }
286 
287 static int
288 soo_posix_fadvise(struct file *fp, off_t offset, off_t len, int advice)
289 {
290 
291 	return SET_ERROR(ESPIPE);
292 }
293