xref: /openbsd/sys/dev/firmload.c (revision 17df1aa7)
1 /*	$OpenBSD: firmload.c,v 1.9 2008/03/08 19:15:26 espie Exp $	*/
2 
3 /*
4  * Copyright (c) 2004 Theo de Raadt <deraadt@openbsd.org>
5  *
6  * Permission to use, copy, modify, and distribute this software for any
7  * purpose with or without fee is hereby granted, provided that the above
8  * copyright notice and this permission notice appear in all copies.
9  *
10  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
11  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
13  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
14  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
15  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
16  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17  */
18 
19 #include <sys/param.h>
20 #include <sys/systm.h>
21 #include <sys/syslimits.h>
22 #include <sys/time.h>
23 #include <sys/namei.h>
24 #include <sys/vnode.h>
25 #include <sys/mount.h>
26 #include <sys/errno.h>
27 #include <sys/malloc.h>
28 #include <sys/proc.h>
29 #include <sys/device.h>
30 
31 int
32 loadfirmware(const char *name, u_char **bufp, size_t *buflen)
33 {
34 	struct proc *p = curproc;
35 	struct nameidata nid;
36 	char *path, *ptr;
37 	struct iovec iov;
38 	struct uio uio;
39 	struct vattr va;
40 	int error;
41 
42 	if (!rootvp || !vcount(rootvp))
43 		return (EIO);
44 
45 	path = malloc(MAXPATHLEN, M_TEMP, M_NOWAIT);
46 	if (path == NULL)
47 		return (ENOMEM);
48 
49 	if (snprintf(path, MAXPATHLEN, "/etc/firmware/%s", name) >=
50 	    MAXPATHLEN) {
51 		error = ENAMETOOLONG;
52 		goto err;
53 	}
54 
55 	NDINIT(&nid, LOOKUP, NOFOLLOW|LOCKLEAF, UIO_SYSSPACE, path, p);
56 	error = namei(&nid);
57 #ifdef RAMDISK_HOOKS
58 	/* try again with mounted disk */
59 	if (error) {
60 		if (snprintf(path, MAXPATHLEN, "/mnt/etc/firmware/%s", name) >=
61 		    MAXPATHLEN) {
62 			error = ENAMETOOLONG;
63 			goto err;
64 		}
65 
66 		NDINIT(&nid, LOOKUP, NOFOLLOW|LOCKLEAF, UIO_SYSSPACE, path, p);
67 		error = namei(&nid);
68 	}
69 #endif
70 	if (error)
71 		goto err;
72 	error = VOP_GETATTR(nid.ni_vp, &va, p->p_ucred, p);
73 	if (error)
74 		goto fail;
75 	if (nid.ni_vp->v_type != VREG || va.va_size == 0) {
76 		error = EINVAL;
77 		goto fail;
78 	}
79 	if (va.va_size > FIRMWARE_MAX) {
80 		error = E2BIG;
81 		goto fail;
82 	}
83 	ptr = malloc(va.va_size, M_DEVBUF, M_NOWAIT);
84 	if (ptr == NULL) {
85 		error = ENOMEM;
86 		goto fail;
87 	}
88 
89 	iov.iov_base = ptr;
90 	iov.iov_len = va.va_size;
91 	uio.uio_iov = &iov;
92 	uio.uio_iovcnt = 1;
93 	uio.uio_offset = 0;
94 	uio.uio_resid = va.va_size;
95 	uio.uio_segflg = UIO_SYSSPACE;
96 	uio.uio_rw = UIO_READ;
97 	uio.uio_procp = p;
98 
99 	error = VOP_READ(nid.ni_vp, &uio, 0, p->p_ucred);
100 
101 	if (error == 0) {
102 		*bufp = ptr;
103 		*buflen = va.va_size;
104 	} else
105 		free(ptr, M_DEVBUF);
106 
107 fail:
108 	vput(nid.ni_vp);
109 err:
110 	if (path)
111 		free(path, M_TEMP);
112 	return (error);
113 }
114