1 /*-
2  * Copyright (c) 2006,2008 Joseph Koshy
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  */
26 
27 #include <assert.h>
28 #include <gelf.h>
29 #include <limits.h>
30 #include <stdint.h>
31 
32 #include "_libelf.h"
33 
34 ELFTC_VCSID("$Id: gelf_cap.c 3177 2015-03-30 18:19:41Z emaste $");
35 
36 GElf_Cap *
37 gelf_getcap(Elf_Data *ed, int ndx, GElf_Cap *dst)
38 {
39 	int ec;
40 	Elf *e;
41 	size_t msz;
42 	Elf_Scn *scn;
43 	Elf32_Cap *cap32;
44 	Elf64_Cap *cap64;
45 	uint32_t sh_type;
46 	struct _Libelf_Data *d;
47 
48 	d = (struct _Libelf_Data *) ed;
49 
50 	if (d == NULL || ndx < 0 || dst == NULL ||
51 	    (scn = d->d_scn) == NULL ||
52 	    (e = scn->s_elf) == NULL) {
53 		LIBELF_SET_ERROR(ARGUMENT, 0);
54 		return (NULL);
55 	}
56 
57 	ec = e->e_class;
58 	assert(ec == ELFCLASS32 || ec == ELFCLASS64);
59 
60 	if (ec == ELFCLASS32)
61 		sh_type = scn->s_shdr.s_shdr32.sh_type;
62 	else
63 		sh_type = scn->s_shdr.s_shdr64.sh_type;
64 
65 	if (_libelf_xlate_shtype(sh_type) != ELF_T_CAP) {
66 		LIBELF_SET_ERROR(ARGUMENT, 0);
67 		return (NULL);
68 	}
69 
70 	msz = _libelf_msize(ELF_T_CAP, ec, e->e_version);
71 
72 	assert(msz > 0);
73 
74 	if (msz * (size_t) ndx >= d->d_data.d_size) {
75 		LIBELF_SET_ERROR(ARGUMENT, 0);
76 		return (NULL);
77 	}
78 
79 	if (ec == ELFCLASS32) {
80 
81 		cap32 = (Elf32_Cap *) d->d_data.d_buf + ndx;
82 
83 		dst->c_tag  = cap32->c_tag;
84 		dst->c_un.c_val = (Elf64_Xword) cap32->c_un.c_val;
85 
86 	} else {
87 
88 		cap64 = (Elf64_Cap *) d->d_data.d_buf + ndx;
89 
90 		*dst = *cap64;
91 	}
92 
93 	return (dst);
94 }
95 
96 int
97 gelf_update_cap(Elf_Data *ed, int ndx, GElf_Cap *gc)
98 {
99 	int ec;
100 	Elf *e;
101 	size_t msz;
102 	Elf_Scn *scn;
103 	Elf32_Cap *cap32;
104 	Elf64_Cap *cap64;
105 	uint32_t sh_type;
106 	struct _Libelf_Data *d;
107 
108 	d = (struct _Libelf_Data *) ed;
109 
110 	if (d == NULL || ndx < 0 || gc == NULL ||
111 	    (scn = d->d_scn) == NULL ||
112 	    (e = scn->s_elf) == NULL) {
113 		LIBELF_SET_ERROR(ARGUMENT, 0);
114 		return (0);
115 	}
116 
117 	ec = e->e_class;
118 	assert(ec == ELFCLASS32 || ec == ELFCLASS64);
119 
120 	if (ec == ELFCLASS32)
121 		sh_type = scn->s_shdr.s_shdr32.sh_type;
122 	else
123 		sh_type = scn->s_shdr.s_shdr64.sh_type;
124 
125 	if (_libelf_xlate_shtype(sh_type) != ELF_T_CAP) {
126 		LIBELF_SET_ERROR(ARGUMENT, 0);
127 		return (0);
128 	}
129 
130 	msz = _libelf_msize(ELF_T_CAP, ec, e->e_version);
131 	assert(msz > 0);
132 
133 	if (msz * (size_t) ndx >= d->d_data.d_size) {
134 		LIBELF_SET_ERROR(ARGUMENT, 0);
135 		return (0);
136 	}
137 
138 	if (ec == ELFCLASS32) {
139 		cap32 = (Elf32_Cap *) d->d_data.d_buf + ndx;
140 
141 		LIBELF_COPY_U32(cap32, gc, c_tag);
142 		LIBELF_COPY_U32(cap32, gc, c_un.c_val);
143 	} else {
144 		cap64 = (Elf64_Cap *) d->d_data.d_buf + ndx;
145 
146 		*cap64 = *gc;
147 	}
148 
149 	return (1);
150 }
151