xref: /illumos-gate/usr/src/cmd/sgs/libelf/common/rawdata.c (revision 71269a2275bf5a143dad6461eee2710a344e7261)
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 (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 
22 /*
23  * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 /*	Copyright (c) 1988 AT&T	*/
28 /*	  All Rights Reserved  	*/
29 
30 #pragma ident	"%Z%%M%	%I%	%E% SMI"
31 
32 #include <stdlib.h>
33 #include "libelf.h"
34 #include "decl.h"
35 #include "msg.h"
36 
37 
38 Elf_Data *
39 elf_rawdata(Elf_Scn * scn, Elf_Data * data)
40 {
41 	Dnode *		d = (Dnode *)data;
42 	Dnode *		raw;
43 	Elf_Data *	rc;
44 	Elf *		elf;
45 
46 	if (scn == 0)
47 		return (0);
48 	elf = scn->s_elf;
49 	READLOCKS(elf, scn)
50 	if ((scn->s_myflags & SF_READY) == 0) {
51 		UPGRADELOCKS(elf, scn)
52 		if ((scn->s_myflags & SF_READY) == 0)
53 			(void) _elf_cookscn(scn);
54 		DOWNGRADELOCKS(elf, scn)
55 	}
56 
57 	if (d == 0)
58 		d = scn->s_hdnode;
59 	else
60 		d = d->db_next;
61 
62 	if (d == 0) {
63 		READUNLOCKS(elf, scn)
64 		return (0);
65 	}
66 
67 	if (d->db_scn != scn) {
68 		_elf_seterr(EREQ_DATA, 0);
69 		READUNLOCKS(elf, scn)
70 		return (0);
71 	}
72 
73 	/*
74 	 * The data may come from a previously constructed Dbuf,
75 	 * from the file's raw memory image, or the file system.
76 	 * "Empty" regions get an empty buffer.
77 	 */
78 
79 	if (d->db_raw != 0) {
80 		rc = &d->db_raw->db_data;
81 		READUNLOCKS(elf, scn)
82 		return (rc);
83 	}
84 
85 	if ((raw = _elf_dnode()) == 0)  {
86 		READUNLOCKS(elf, scn)
87 		return (0);
88 	}
89 	raw->db_myflags |= DBF_READY;
90 	if ((d->db_off == 0) || (d->db_fsz == 0)) {
91 		d->db_raw = raw;
92 		raw->db_data.d_size = d->db_shsz;
93 		rc = &raw->db_data;
94 		READUNLOCKS(elf, scn)
95 		return (rc);
96 	}
97 
98 	/*
99 	 * validate the region
100 	 */
101 
102 	if ((d->db_off < 0) ||
103 	    (d->db_off >= elf->ed_fsz) ||
104 	    (elf->ed_fsz - d->db_off < d->db_fsz)) {
105 		_elf_seterr(EFMT_DATA, 0);
106 		free(raw);
107 		READUNLOCKS(elf, scn)
108 		return (0);
109 	}
110 	raw->db_data.d_size = d->db_fsz;
111 	if (elf->ed_raw != 0) {
112 		raw->db_data.d_buf = (Elf_Void *)(elf->ed_raw + d->db_off);
113 		d->db_raw = raw;
114 		rc = &raw->db_data;
115 		READUNLOCKS(elf, scn)
116 		return (rc);
117 	}
118 	raw->db_buf = (Elf_Void *)_elf_read(elf->ed_fd,
119 	    elf->ed_baseoff + d->db_off, d->db_fsz);
120 	if (raw->db_buf == 0) {
121 		free(raw);
122 		READUNLOCKS(elf, scn)
123 		return (0);
124 	}
125 	raw->db_data.d_buf = raw->db_buf;
126 	d->db_raw = raw;
127 	rc = &raw->db_data;
128 	READUNLOCKS(elf, scn)
129 	return (rc);
130 }
131