xref: /illumos-gate/usr/src/lib/libsmbios/common/smb_lib.c (revision 581cede61ac9c14d8d4ea452562a567189eead78)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License, Version 1.0 only
6  * (the "License").  You may not use this file except in compliance
7  * with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or http://www.opensolaris.org/os/licensing.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  */
22 
23 /*
24  * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
25  * Use is subject to license terms.
26  */
27 
28 #pragma ident	"%Z%%M%	%I%	%E% SMI"
29 
30 #include <sys/types.h>
31 #include <sys/smbios_impl.h>
32 #include <sys/sysmacros.h>
33 #include <sys/stat.h>
34 #include <sys/mman.h>
35 
36 #include <alloca.h>
37 #include <limits.h>
38 #include <unistd.h>
39 #include <strings.h>
40 #include <stdlib.h>
41 #include <errno.h>
42 #include <fcntl.h>
43 
44 #pragma init(smb_init)
45 static void
46 smb_init(void)
47 {
48 	_smb_debug = getenv("SMB_DEBUG") != NULL;
49 }
50 
51 static smbios_hdl_t *
52 smb_fileopen(int fd, int version, int flags, int *errp)
53 {
54 	smbios_entry_t *ep = alloca(SMB_ENTRY_MAXLEN);
55 	smbios_hdl_t *shp = NULL;
56 	ssize_t n, elen;
57 	void *stbuf;
58 
59 	if ((n = pread64(fd, ep, sizeof (*ep), 0)) != sizeof (*ep))
60 		return (smb_open_error(shp, errp, n < 0 ? errno : ESMB_NOHDR));
61 
62 	if (strncmp(ep->smbe_eanchor, SMB_ENTRY_EANCHOR, SMB_ENTRY_EANCHORLEN))
63 		return (smb_open_error(shp, errp, ESMB_HEADER));
64 
65 	elen = MIN(ep->smbe_elen, SMB_ENTRY_MAXLEN);
66 
67 	if ((n = pread64(fd, ep, elen, 0)) != elen)
68 		return (smb_open_error(shp, errp, n < 0 ? errno : ESMB_NOHDR));
69 
70 	if ((stbuf = smb_alloc(ep->smbe_stlen)) == NULL)
71 		return (smb_open_error(shp, errp, ESMB_NOMEM));
72 
73 	if ((n = pread64(fd, stbuf, ep->smbe_stlen,
74 	    (off64_t)ep->smbe_staddr)) != ep->smbe_stlen) {
75 		smb_free(stbuf, ep->smbe_stlen);
76 		return (smb_open_error(shp, errp, n < 0 ? errno : ESMB_NOSTAB));
77 	}
78 
79 	shp = smbios_bufopen(ep, stbuf, ep->smbe_stlen, version, flags, errp);
80 
81 	if (shp != NULL)
82 		shp->sh_flags |= SMB_FL_BUFALLOC;
83 	else
84 		smb_free(stbuf, ep->smbe_stlen);
85 
86 	return (shp);
87 }
88 
89 static smbios_hdl_t *
90 smb_biosopen(int fd, int version, int flags, int *errp)
91 {
92 	smbios_entry_t *ep = alloca(SMB_ENTRY_MAXLEN);
93 	smbios_hdl_t *shp = NULL;
94 	size_t pgsize, pgmask, pgoff;
95 	void *stbuf, *bios, *p, *q;
96 
97 	bios = mmap(NULL, SMB_RANGE_LIMIT - SMB_RANGE_START + 1,
98 	    PROT_READ, MAP_SHARED, fd, (uint32_t)SMB_RANGE_START);
99 
100 	if (bios == MAP_FAILED)
101 		return (smb_open_error(shp, errp, ESMB_MAPDEV));
102 
103 	q = (void *)((uintptr_t)bios + SMB_RANGE_LIMIT - SMB_RANGE_START + 1);
104 
105 	for (p = bios; p < q; p = (void *)((uintptr_t)p + 16)) {
106 		if (strncmp(p, SMB_ENTRY_EANCHOR, SMB_ENTRY_EANCHORLEN) == 0)
107 			break;
108 	}
109 
110 	if (p >= q) {
111 		(void) munmap(bios, SMB_RANGE_LIMIT - SMB_RANGE_START + 1);
112 		return (smb_open_error(NULL, errp, ESMB_NOTFOUND));
113 	}
114 
115 	bcopy(p, ep, sizeof (smbios_entry_t));
116 	ep->smbe_elen = MIN(ep->smbe_elen, SMB_ENTRY_MAXLEN);
117 	bcopy(p, ep, ep->smbe_elen);
118 	(void) munmap(bios, SMB_RANGE_LIMIT - SMB_RANGE_START + 1);
119 
120 	pgsize = getpagesize();
121 	pgmask = ~(pgsize - 1);
122 	pgoff = ep->smbe_staddr & ~pgmask;
123 
124 	bios = mmap(NULL, ep->smbe_stlen + pgoff,
125 	    PROT_READ, MAP_SHARED, fd, ep->smbe_staddr & pgmask);
126 
127 	if (bios == MAP_FAILED)
128 		return (smb_open_error(shp, errp, ESMB_MAPDEV));
129 
130 	if ((stbuf = smb_alloc(ep->smbe_stlen)) == NULL) {
131 		(void) munmap(bios, ep->smbe_stlen + pgoff);
132 		return (smb_open_error(shp, errp, ESMB_NOMEM));
133 	}
134 
135 	bcopy((char *)bios + pgoff, stbuf, ep->smbe_stlen);
136 	(void) munmap(bios, ep->smbe_stlen + pgoff);
137 	shp = smbios_bufopen(ep, stbuf, ep->smbe_stlen, version, flags, errp);
138 
139 	if (shp != NULL)
140 		shp->sh_flags |= SMB_FL_BUFALLOC;
141 	else
142 		smb_free(stbuf, ep->smbe_stlen);
143 
144 	return (shp);
145 }
146 
147 smbios_hdl_t *
148 smbios_fdopen(int fd, int version, int flags, int *errp)
149 {
150 	struct stat64 st1, st2;
151 
152 	if (stat64(SMB_BIOS_DEVICE, &st1) == 0 && fstat64(fd, &st2) == 0 &&
153 	    S_ISCHR(st2.st_mode) && st1.st_rdev == st2.st_rdev)
154 		return (smb_biosopen(fd, version, flags, errp));
155 	else
156 		return (smb_fileopen(fd, version, flags, errp));
157 }
158 
159 smbios_hdl_t *
160 smbios_open(const char *file, int version, int flags, int *errp)
161 {
162 	smbios_hdl_t *shp;
163 	int fd;
164 
165 	if ((fd = open64(file ? file : SMB_SMBIOS_DEVICE, O_RDONLY)) == -1) {
166 		if ((errno == ENOENT || errno == ENXIO) &&
167 		    (file == NULL || strcmp(file, SMB_SMBIOS_DEVICE) == 0))
168 			errno = ESMB_NOTFOUND;
169 		return (smb_open_error(NULL, errp, errno));
170 	}
171 
172 	shp = smbios_fdopen(fd, version, flags, errp);
173 	(void) close(fd);
174 	return (shp);
175 }
176 
177 static int
178 smbios_xwrite(smbios_hdl_t *shp, int fd, const void *buf, size_t buflen)
179 {
180 	ssize_t resid = buflen;
181 	ssize_t len;
182 
183 	while (resid != 0) {
184 		if ((len = write(fd, buf, resid)) <= 0)
185 			return (smb_set_errno(shp, errno));
186 		resid -= len;
187 		buf = (uchar_t *)buf + len;
188 	}
189 
190 	return (0);
191 }
192 
193 int
194 smbios_write(smbios_hdl_t *shp, int fd)
195 {
196 	smbios_entry_t ep;
197 	off64_t off = lseek64(fd, 0, SEEK_CUR) + P2ROUNDUP(sizeof (ep), 16);
198 
199 	if (off > UINT32_MAX)
200 		return (smb_set_errno(shp, EOVERFLOW));
201 
202 	bcopy(&shp->sh_ent, &ep, sizeof (ep));
203 	ep.smbe_staddr = (uint32_t)off;
204 	smbios_checksum(shp, &ep);
205 
206 	if (smbios_xwrite(shp, fd, &ep, sizeof (ep)) == -1 ||
207 	    lseek64(fd, off, SEEK_SET) != off ||
208 	    smbios_xwrite(shp, fd, shp->sh_buf, shp->sh_buflen) == -1)
209 		return (-1);
210 
211 	return (0);
212 }
213