xref: /netbsd-src/share/examples/rump/ttyserv/ttyserv.c (revision b1c86f5f087524e68db12794ee9c3e3da1ab17a0)
1 /*	$NetBSD: ttyserv.c,v 1.2 2010/06/24 13:03:05 hannken Exp $	*/
2 
3 /*
4  * Copyright (c) 2009, 2010 Antti Kantee.  All Rights Reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS
16  * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
17  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
18  * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
21  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25  * SUCH DAMAGE.
26  */
27 
28 /*
29  * This is a [quick, simple & dirty] userspace tty/ucom server.
30  * We probe USB devices using rump and attach them to the host kernel
31  * using pud(4).
32  */
33 
34 #include <sys/types.h>
35 #include <sys/syslimits.h>
36 
37 #include <dev/pud/pud_msgif.h>
38 
39 #include <rump/rump.h>
40 
41 #include <assert.h>
42 #include <err.h>
43 #include <errno.h>
44 #include <fcntl.h>
45 #include <paths.h>
46 #include <pthread.h>
47 #include <stdio.h>
48 #include <stdlib.h>
49 #include <string.h>
50 #include <unistd.h>
51 
52 /*
53  * No devfs?  No problem.  We just hack a bit & wait for the dust to settle.
54  */
55 #define MYMAJOR 412
56 static int
57 makenodes(void)
58 {
59 	struct stat sb;
60 	int rv;
61 
62 	if (stat("rumpttyU0", &sb) != 0)
63 		rv = mknod("rumpttyU0", S_IFCHR | 0666, makedev(MYMAJOR, 0));
64 	if (rv != 0 && !(rv == -1 && errno == EEXIST))
65 		return rv;
66 
67 	if (stat("rumpttyU1", &sb) != 0)
68 		rv = mknod("rumpttyU1", S_IFCHR | 0666, makedev(MYMAJOR, 1));
69 	if (rv != 0 && !(rv == -1 && errno == EEXIST))
70 		return rv;
71 
72 	return 0;
73 }
74 
75 static struct vnode *devvps[2];
76 static kauth_cred_t rootcred;
77 static int fd;
78 
79 static void *
80 handlereq(void *arg)
81 {
82 	struct vnode *devvp;
83 	struct pud_creq_open *pr_open;
84 	struct pud_creq_close *pr_close;
85 	struct pud_req_readwrite *pr_rw;
86 	struct pud_req_ioctl *pr_ioctl;
87 	struct uio *uio;
88 	size_t reslen;
89 	struct pud_req *pdr = arg;
90 	int minordev, rv;
91 	ssize_t n;
92 
93 	minordev = minor(pdr->pdr_dev);
94 	if (minordev < 0 || minordev >= 8) {
95 		rv = ENXIO;
96 		goto sendresponse;
97 	}
98 	devvp = devvps[minordev];
99 
100 	switch (pdr->pdr_reqtype) {
101 	case PUD_CDEV_OPEN:
102 		pr_open = (void *)pdr;
103 		RUMP_VOP_LOCK(devvp, RUMP_LK_EXCLUSIVE);
104 		rv = RUMP_VOP_OPEN(devvp, pr_open->pm_fmt, rootcred);
105 		RUMP_VOP_UNLOCK(devvp);
106 		break;
107 
108 	case PUD_CDEV_CLOSE:
109 		pr_close = (void *)pdr;
110 		RUMP_VOP_LOCK(devvp, RUMP_LK_EXCLUSIVE);
111 		rv = RUMP_VOP_CLOSE(devvp, pr_close->pm_fmt, rootcred);
112 		RUMP_VOP_UNLOCK(devvp);
113 		break;
114 
115 	case PUD_CDEV_IOCTL:
116 		pr_ioctl = (void *)pdr;
117 		rv = RUMP_VOP_IOCTL(devvp, pr_ioctl->pm_iocmd,
118 		    pr_ioctl->pm_data, pr_ioctl->pm_flag, rootcred);
119 		break;
120 
121 	case PUD_CDEV_READ:
122 		pr_rw = (void *)pdr;
123 		assert(pr_rw->pm_resid <= 64*1024);
124 		uio = rump_pub_uio_setup(&pr_rw->pm_data[0],
125 		    pr_rw->pm_resid, pr_rw->pm_offset, RUMPUIO_READ);
126 		RUMP_VOP_LOCK(devvp, RUMP_LK_SHARED);
127 		rv = RUMP_VOP_READ(devvp, uio, 0, rootcred);
128 		RUMP_VOP_UNLOCK(devvp);
129 		reslen = rump_pub_uio_free(uio);
130 		pdr->pdr_pth.pth_framelen -= reslen;
131 		pr_rw->pm_resid = reslen;
132 		break;
133 
134 	case PUD_CDEV_WRITE:
135 		pr_rw = (void *)pdr;
136 		uio = rump_pub_uio_setup(&pr_rw->pm_data[0],
137 		    pr_rw->pm_resid, pr_rw->pm_offset, RUMPUIO_WRITE);
138 		RUMP_VOP_LOCK(devvp, RUMP_LK_EXCLUSIVE);
139 		rv = RUMP_VOP_WRITE(devvp, uio, 0, rootcred);
140 		RUMP_VOP_UNLOCK(devvp);
141 		reslen = rump_pub_uio_free(uio);
142 		pr_rw->pm_resid = reslen;
143 		pdr->pdr_pth.pth_framelen=sizeof(struct pud_creq_write);
144 		rv = 0;
145 		break;
146 	default:
147 		printf("unknown request %d\n", pdr->pdr_reqtype);
148 		abort();
149 	}
150 
151 sendresponse:
152 	printf("result %d\n", rv);
153 	pdr->pdr_rv = rv;
154 	n = write(fd, pdr, pdr->pdr_pth.pth_framelen);
155 	assert(n == (ssize_t)pdr->pdr_pth.pth_framelen);
156 
157 	pthread_exit(NULL);
158 }
159 
160 int
161 main(int argc, char *argv[])
162 {
163 	struct pud_conf_reg pcr;
164 	struct pud_req *pdr;
165 	ssize_t n;
166 	int rv;
167 
168 	if (makenodes() == -1)
169 		err(1, "makenodes");
170 
171 	fd = open(_PATH_PUD, O_RDWR);
172 	if (fd == -1)
173 		err(1, "open");
174 
175 	memset(&pcr, 0, sizeof(pcr));
176 	pcr.pm_pdr.pdr_pth.pth_framelen = sizeof(struct pud_conf_reg);
177 	pcr.pm_version = PUD_DEVELVERSION | PUD_VERSION;
178 	pcr.pm_pdr.pdr_reqclass = PUD_REQ_CONF;
179 	pcr.pm_pdr.pdr_reqtype = PUD_CONF_REG;
180 
181 	pcr.pm_regdev = makedev(MYMAJOR, 0);
182 	pcr.pm_flags = PUD_CONFFLAG_BDEV;
183 	strlcpy(pcr.pm_devname, "youmass", sizeof(pcr.pm_devname));
184 
185 	n = write(fd, &pcr, pcr.pm_pdr.pdr_pth.pth_framelen);
186 	if (n == -1)
187 		err(1, "configure"); /* XXX: doubles as protocol error */
188 
189 	rump_boot_sethowto(RUMP_AB_VERBOSE);
190 	rump_init();
191 
192 	if ((rv = rump_pub_namei(RUMP_NAMEI_LOOKUP, 0, "/dev/ttyU0",
193 	    NULL, &devvps[0], NULL)) != 0)
194 		errx(1, "raw device 0 lookup failed %d", rv);
195 	if ((rv = rump_pub_namei(RUMP_NAMEI_LOOKUP, 0, "/dev/ttyU1",
196 	    NULL, &devvps[1], NULL)) != 0)
197 		errx(1, "raw device 1 lookup failed %d", rv);
198 
199 	rootcred = rump_pub_cred_create(0, 0, 0, NULL);
200 
201 	/* process requests ad infinitum */
202 	for (;;) {
203 		pthread_t pt;
204 
205 #define PDRSIZE (64*1024+1024)
206 		pdr = malloc(PDRSIZE);
207 		if (pdr == NULL)
208 			err(1, "malloc");
209 
210 		n = read(fd, pdr, PDRSIZE);
211 		if (n == -1)
212 			err(1, "read");
213 
214 		/*
215 		 * tip & cu fork and read/write at the same time.  hence,
216 		 * we need a multithreaded server as otherwise read requests
217 		 * will block eternally since no writes can be done.
218 		 *
219 		 * XXX: do this properly (detached threads, or pool)
220 		 */
221 		pthread_create(&pt, NULL, handlereq, pdr);
222 	}
223 }
224