rumpcopy.c revision 1.22 
1/*	$NetBSD: rumpcopy.c,v 1.22 2016/05/25 17:43:58 christos Exp $	*/
2
3/*
4 * Copyright (c) 2009 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#include <sys/cdefs.h>
29__KERNEL_RCSID(0, "$NetBSD: rumpcopy.c,v 1.22 2016/05/25 17:43:58 christos Exp $");
30
31#include <sys/param.h>
32#include <sys/lwp.h>
33#include <sys/systm.h>
34#include <sys/uio.h>
35
36#include <rump-sys/kern.h>
37
38#include <rump/rumpuser.h>
39
40int
41copyin(const void *uaddr, void *kaddr, size_t len)
42{
43	int error = 0;
44
45	if (__predict_false(uaddr == NULL && len)) {
46		return EFAULT;
47	}
48
49	if (RUMP_LOCALPROC_P(curproc)) {
50		memcpy(kaddr, uaddr, len);
51	} else if (len) {
52		error = rump_sysproxy_copyin(RUMP_SPVM2CTL(curproc->p_vmspace),
53		    uaddr, kaddr, len);
54	}
55
56	return error;
57}
58
59int
60copyout(const void *kaddr, void *uaddr, size_t len)
61{
62	int error = 0;
63
64	if (__predict_false(uaddr == NULL && len)) {
65		return EFAULT;
66	}
67
68	if (RUMP_LOCALPROC_P(curproc)) {
69		memcpy(uaddr, kaddr, len);
70	} else if (len) {
71		error = rump_sysproxy_copyout(RUMP_SPVM2CTL(curproc->p_vmspace),
72		    kaddr, uaddr, len);
73	}
74	return error;
75}
76
77int
78subyte(void *uaddr, int byte)
79{
80	int error = 0;
81
82	if (RUMP_LOCALPROC_P(curproc))
83		*(char *)uaddr = byte;
84	else
85		error = rump_sysproxy_copyout(RUMP_SPVM2CTL(curproc->p_vmspace),
86		    &byte, uaddr, 1);
87
88	return error;
89}
90
91int
92copystr(const void *kfaddr, void *kdaddr, size_t len, size_t *done)
93{
94	uint8_t *to = kdaddr;
95	const uint8_t *from = kfaddr;
96	size_t actlen = 0;
97
98	while (len-- > 0 && (*to++ = *from++) != 0)
99		actlen++;
100
101	if (len+1 == 0 && *(to-1) != 0)
102		return ENAMETOOLONG;
103
104	if (done)
105		*done = actlen+1; /* + '\0' */
106	return 0;
107}
108
109int
110copyinstr(const void *uaddr, void *kaddr, size_t len, size_t *done)
111{
112	uint8_t *to;
113	int rv;
114
115	if (len == 0)
116		return 0;
117
118	if (__predict_false(uaddr == NULL)) {
119		return EFAULT;
120	}
121
122	if (RUMP_LOCALPROC_P(curproc))
123		return copystr(uaddr, kaddr, len, done);
124
125	if ((rv = rump_sysproxy_copyinstr(RUMP_SPVM2CTL(curproc->p_vmspace),
126	    uaddr, kaddr, &len)) != 0)
127		return rv;
128
129	/* figure out if we got a terminated string or not */
130	to = (uint8_t *)kaddr + (len-1);
131	while (to >= (uint8_t *)kaddr) {
132		if (*to == 0)
133			goto found;
134		to--;
135	}
136	return ENAMETOOLONG;
137
138 found:
139	if (done)
140		*done = strlen(kaddr)+1; /* includes termination */
141
142	return 0;
143}
144
145int
146copyoutstr(const void *kaddr, void *uaddr, size_t len, size_t *done)
147{
148	size_t slen;
149	int error;
150
151	if (__predict_false(uaddr == NULL && len)) {
152		return EFAULT;
153	}
154
155	if (RUMP_LOCALPROC_P(curproc))
156		return copystr(kaddr, uaddr, len, done);
157
158	slen = strlen(kaddr)+1;
159	if (slen > len)
160		return ENAMETOOLONG;
161
162	error = rump_sysproxy_copyoutstr(RUMP_SPVM2CTL(curproc->p_vmspace),
163	    kaddr, uaddr, &slen);
164	if (done)
165		*done = slen;
166
167	return error;
168}
169
170int
171kcopy(const void *src, void *dst, size_t len)
172{
173
174	memcpy(dst, src, len);
175	return 0;
176}
177
178/*
179 * Low-level I/O routine.  This is used only when "all else fails",
180 * i.e. the current thread does not have an appropriate vm context.
181 */
182int
183uvm_io(struct vm_map *vm, struct uio *uio, int flag)
184{
185	int error = 0;
186
187	/* loop over iovecs one-by-one and copyout */
188	for (; uio->uio_resid && uio->uio_iovcnt;
189	    uio->uio_iovcnt--, uio->uio_iov++) {
190		struct iovec *iov = uio->uio_iov;
191		size_t curlen = MIN(uio->uio_resid, iov->iov_len);
192
193		if (__predict_false(curlen == 0))
194			continue;
195
196		if (uio->uio_rw == UIO_READ) {
197			error = rump_sysproxy_copyin(RUMP_SPVM2CTL(vm),
198			    (void *)(vaddr_t)uio->uio_offset, iov->iov_base,
199			    curlen);
200		} else {
201			error = rump_sysproxy_copyout(RUMP_SPVM2CTL(vm),
202			    iov->iov_base, (void *)(vaddr_t)uio->uio_offset,
203			    curlen);
204		}
205		if (error)
206			break;
207
208		iov->iov_base = (uint8_t *)iov->iov_base + curlen;
209		iov->iov_len -= curlen;
210
211		uio->uio_resid -= curlen;
212		uio->uio_offset += curlen;
213	}
214
215	return error;
216}
217
218/*
219 * Copy one byte from userspace to kernel.
220 */
221int
222fubyte(const void *base)
223{
224	unsigned char val;
225	int error;
226
227	error = copyin(base, &val, sizeof(char));
228	if (error != 0)
229		return -1;
230
231	return (int)val;
232}
233