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 3732 2019-04-22 11:08:38Z jkoshy $");
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 	if ((msz = _libelf_msize(ELF_T_CAP, ec, e->e_version)) == 0)
71 		return (NULL);
72 
73 	if (msz * (size_t) ndx >= d->d_data.d_size) {
74 		LIBELF_SET_ERROR(ARGUMENT, 0);
75 		return (NULL);
76 	}
77 
78 	if (ec == ELFCLASS32) {
79 
80 		cap32 = (Elf32_Cap *) d->d_data.d_buf + ndx;
81 
82 		dst->c_tag  = cap32->c_tag;
83 		dst->c_un.c_val = (Elf64_Xword) cap32->c_un.c_val;
84 
85 	} else {
86 
87 		cap64 = (Elf64_Cap *) d->d_data.d_buf + ndx;
88 
89 		*dst = *cap64;
90 	}
91 
92 	return (dst);
93 }
94 
95 int
96 gelf_update_cap(Elf_Data *ed, int ndx, GElf_Cap *gc)
97 {
98 	int ec;
99 	Elf *e;
100 	size_t msz;
101 	Elf_Scn *scn;
102 	Elf32_Cap *cap32;
103 	Elf64_Cap *cap64;
104 	uint32_t sh_type;
105 	struct _Libelf_Data *d;
106 
107 	d = (struct _Libelf_Data *) ed;
108 
109 	if (d == NULL || ndx < 0 || gc == NULL ||
110 	    (scn = d->d_scn) == NULL ||
111 	    (e = scn->s_elf) == NULL) {
112 		LIBELF_SET_ERROR(ARGUMENT, 0);
113 		return (0);
114 	}
115 
116 	ec = e->e_class;
117 	assert(ec == ELFCLASS32 || ec == ELFCLASS64);
118 
119 	if (ec == ELFCLASS32)
120 		sh_type = scn->s_shdr.s_shdr32.sh_type;
121 	else
122 		sh_type = scn->s_shdr.s_shdr64.sh_type;
123 
124 	if (_libelf_xlate_shtype(sh_type) != ELF_T_CAP) {
125 		LIBELF_SET_ERROR(ARGUMENT, 0);
126 		return (0);
127 	}
128 
129 	if ((msz = _libelf_msize(ELF_T_CAP, ec, e->e_version)) == 0)
130 		return (0);
131 
132 	if (msz * (size_t) ndx >= d->d_data.d_size) {
133 		LIBELF_SET_ERROR(ARGUMENT, 0);
134 		return (0);
135 	}
136 
137 	if (ec == ELFCLASS32) {
138 		cap32 = (Elf32_Cap *) d->d_data.d_buf + ndx;
139 
140 		LIBELF_COPY_U32(cap32, gc, c_tag);
141 		LIBELF_COPY_U32(cap32, gc, c_un.c_val);
142 	} else {
143 		cap64 = (Elf64_Cap *) d->d_data.d_buf + ndx;
144 
145 		*cap64 = *gc;
146 	}
147 
148 	return (1);
149 }
150