xref: /illumos-gate/usr/src/cmd/sgs/libelf/common/rawdata.c (revision 8119dad84d6416f13557b0ba8e2aaf9064cbcfd3)
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 #include <stdlib.h>
31 #include "libelf.h"
32 #include "decl.h"
33 #include "msg.h"
34 
35 
36 Elf_Data *
37 elf_rawdata(Elf_Scn * scn, Elf_Data * data)
38 {
39 	Dnode *		d = (Dnode *)data;
40 	Dnode *		raw;
41 	Elf_Data *	rc;
42 	Elf *		elf;
43 
44 	if (scn == 0)
45 		return (0);
46 	elf = scn->s_elf;
47 	READLOCKS(elf, scn)
48 	if ((scn->s_myflags & SF_READY) == 0) {
49 		UPGRADELOCKS(elf, scn)
50 		if ((scn->s_myflags & SF_READY) == 0)
51 			(void) _elf_cookscn(scn);
52 		DOWNGRADELOCKS(elf, scn)
53 	}
54 
55 	if (d == 0)
56 		d = scn->s_hdnode;
57 	else
58 		d = d->db_next;
59 
60 	if (d == 0) {
61 		READUNLOCKS(elf, scn)
62 		return (0);
63 	}
64 
65 	if (d->db_scn != scn) {
66 		_elf_seterr(EREQ_DATA, 0);
67 		READUNLOCKS(elf, scn)
68 		return (0);
69 	}
70 
71 	/*
72 	 * The data may come from a previously constructed Dbuf,
73 	 * from the file's raw memory image, or the file system.
74 	 * "Empty" regions get an empty buffer.
75 	 */
76 
77 	if (d->db_raw != 0) {
78 		rc = &d->db_raw->db_data;
79 		READUNLOCKS(elf, scn)
80 		return (rc);
81 	}
82 
83 	if ((raw = _elf_dnode()) == 0)  {
84 		READUNLOCKS(elf, scn)
85 		return (0);
86 	}
87 	raw->db_myflags |= DBF_READY;
88 	if ((d->db_off == 0) || (d->db_fsz == 0)) {
89 		d->db_raw = raw;
90 		raw->db_data.d_size = d->db_shsz;
91 		rc = &raw->db_data;
92 		READUNLOCKS(elf, scn)
93 		return (rc);
94 	}
95 
96 	/*
97 	 * validate the region
98 	 */
99 
100 	if ((d->db_off < 0) ||
101 	    (d->db_off >= elf->ed_fsz) ||
102 	    (elf->ed_fsz - d->db_off < d->db_fsz)) {
103 		_elf_seterr(EFMT_DATA, 0);
104 		free(raw);
105 		READUNLOCKS(elf, scn)
106 		return (0);
107 	}
108 	raw->db_data.d_size = d->db_fsz;
109 	if (elf->ed_raw != 0) {
110 		raw->db_data.d_buf = (Elf_Void *)(elf->ed_raw + d->db_off);
111 		d->db_raw = raw;
112 		rc = &raw->db_data;
113 		READUNLOCKS(elf, scn)
114 		return (rc);
115 	}
116 	raw->db_buf = (Elf_Void *)_elf_read(elf->ed_fd,
117 	    elf->ed_baseoff + d->db_off, d->db_fsz);
118 	if (raw->db_buf == 0) {
119 		free(raw);
120 		READUNLOCKS(elf, scn)
121 		return (0);
122 	}
123 	raw->db_data.d_buf = raw->db_buf;
124 	d->db_raw = raw;
125 	rc = &raw->db_data;
126 	READUNLOCKS(elf, scn)
127 	return (rc);
128 }
129