1 /*-
2  * Copyright (c) 2006,2008,2010 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 /*
28  * Internal APIs
29  */
30 
31 #include <assert.h>
32 #include <errno.h>
33 #include <libelf.h>
34 #include <stdlib.h>
35 #include <string.h>
36 
37 #include "_libelf.h"
38 
39 ELFTC_VCSID("$Id: libelf_allocate.c 3174 2015-03-27 17:13:41Z emaste $");
40 
41 Elf *
42 _libelf_allocate_elf(void)
43 {
44 	Elf *e;
45 
46 	if ((e = malloc(sizeof(*e))) == NULL) {
47 		LIBELF_SET_ERROR(RESOURCE, errno);
48 		return NULL;
49 	}
50 
51 	e->e_activations = 1;
52 	e->e_hdr.e_rawhdr = NULL;
53 	e->e_byteorder   = ELFDATANONE;
54 	e->e_class       = ELFCLASSNONE;
55 	e->e_cmd         = ELF_C_NULL;
56 	e->e_fd          = -1;
57 	e->e_flags	 = 0;
58 	e->e_kind        = ELF_K_NONE;
59 	e->e_parent      = NULL;
60 	e->e_rawfile     = NULL;
61 	e->e_rawsize     = 0;
62 	e->e_version     = LIBELF_PRIVATE(version);
63 
64 	(void) memset(&e->e_u, 0, sizeof(e->e_u));
65 
66 	return (e);
67 }
68 
69 void
70 _libelf_init_elf(Elf *e, Elf_Kind kind)
71 {
72 	assert(e != NULL);
73 	assert(e->e_kind == ELF_K_NONE);
74 
75 	e->e_kind = kind;
76 
77 	switch (kind) {
78 	case ELF_K_ELF:
79 		STAILQ_INIT(&e->e_u.e_elf.e_scn);
80 		break;
81 	default:
82 		break;
83 	}
84 }
85 
86 #define	FREE(P)		do {				\
87 		if (P)					\
88 			free(P);			\
89 	} while (0)
90 
91 
92 Elf *
93 _libelf_release_elf(Elf *e)
94 {
95 	Elf_Arhdr *arh;
96 
97 	switch (e->e_kind) {
98 	case ELF_K_AR:
99 		FREE(e->e_u.e_ar.e_symtab);
100 		break;
101 
102 	case ELF_K_ELF:
103 		switch (e->e_class) {
104 		case ELFCLASS32:
105 			FREE(e->e_u.e_elf.e_ehdr.e_ehdr32);
106 			FREE(e->e_u.e_elf.e_phdr.e_phdr32);
107 			break;
108 		case ELFCLASS64:
109 			FREE(e->e_u.e_elf.e_ehdr.e_ehdr64);
110 			FREE(e->e_u.e_elf.e_phdr.e_phdr64);
111 			break;
112 		}
113 
114 		assert(STAILQ_EMPTY(&e->e_u.e_elf.e_scn));
115 
116 		if (e->e_flags & LIBELF_F_AR_HEADER) {
117 			arh = e->e_hdr.e_arhdr;
118 			FREE(arh->ar_name);
119 			FREE(arh->ar_rawname);
120 			free(arh);
121 		}
122 
123 		break;
124 
125 	default:
126 		break;
127 	}
128 
129 	free(e);
130 
131 	return (NULL);
132 }
133 
134 struct _Libelf_Data *
135 _libelf_allocate_data(Elf_Scn *s)
136 {
137 	struct _Libelf_Data *d;
138 
139 	if ((d = calloc((size_t) 1, sizeof(*d))) == NULL) {
140 		LIBELF_SET_ERROR(RESOURCE, 0);
141 		return (NULL);
142 	}
143 
144 	d->d_scn = s;
145 
146 	return (d);
147 }
148 
149 struct _Libelf_Data *
150 _libelf_release_data(struct _Libelf_Data *d)
151 {
152 
153 	if (d->d_flags & LIBELF_F_DATA_MALLOCED)
154 		free(d->d_data.d_buf);
155 
156 	free(d);
157 
158 	return (NULL);
159 }
160 
161 Elf_Scn *
162 _libelf_allocate_scn(Elf *e, size_t ndx)
163 {
164 	Elf_Scn *s;
165 
166 	if ((s = calloc((size_t) 1, sizeof(Elf_Scn))) == NULL) {
167 		LIBELF_SET_ERROR(RESOURCE, errno);
168 		return (NULL);
169 	}
170 
171 	s->s_elf = e;
172 	s->s_ndx = ndx;
173 
174 	STAILQ_INIT(&s->s_data);
175 	STAILQ_INIT(&s->s_rawdata);
176 
177 	STAILQ_INSERT_TAIL(&e->e_u.e_elf.e_scn, s, s_next);
178 
179 	return (s);
180 }
181 
182 Elf_Scn *
183 _libelf_release_scn(Elf_Scn *s)
184 {
185 	Elf *e;
186 	struct _Libelf_Data *d, *td;
187 
188 	assert(s != NULL);
189 
190 	STAILQ_FOREACH_SAFE(d, &s->s_data, d_next, td) {
191 		STAILQ_REMOVE(&s->s_data, d, _Libelf_Data, d_next);
192 		d = _libelf_release_data(d);
193 	}
194 
195 	STAILQ_FOREACH_SAFE(d, &s->s_rawdata, d_next, td) {
196 		assert((d->d_flags & LIBELF_F_DATA_MALLOCED) == 0);
197 		STAILQ_REMOVE(&s->s_rawdata, d, _Libelf_Data, d_next);
198 		d = _libelf_release_data(d);
199 	}
200 
201 	e = s->s_elf;
202 
203 	assert(e != NULL);
204 
205 	STAILQ_REMOVE(&e->e_u.e_elf.e_scn, s, _Elf_Scn, s_next);
206 
207 	free(s);
208 
209 	return (NULL);
210 }
211