1/*-
2 * Copyright (c) 2006 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 * $FreeBSD$
27 */
28
29#ifndef	__LIBELF_H_
30#define	__LIBELF_H_
31
32#include <sys/queue.h>
33
34#ifndef	NULL
35#define NULL 	((void *) 0)
36#endif
37
38/*
39 * Library-private data structures.
40 */
41
42#define LIBELF_MSG_SIZE	256
43
44struct _libelf_globals {
45	int		libelf_arch;
46	unsigned int	libelf_byteorder;
47	int		libelf_class;
48	int		libelf_error;
49	int		libelf_fillchar;
50	unsigned int	libelf_version;
51	char		libelf_msg[LIBELF_MSG_SIZE];
52};
53
54extern struct _libelf_globals _libelf;
55
56#define	LIBELF_PRIVATE(N)	(_libelf.libelf_##N)
57
58#define	LIBELF_ELF_ERROR_MASK	0xFF
59#define	LIBELF_OS_ERROR_SHIFT	8
60
61#define	LIBELF_SET_ERROR(E, O) do {					\
62	LIBELF_PRIVATE(error) = ((ELF_E_##E & LIBELF_ELF_ERROR_MASK)|	\
63	    ((O) << LIBELF_OS_ERROR_SHIFT));				\
64	} while (0)
65
66#define	LIBELF_ADJUST_AR_SIZE(S)	(((S) + 1U) & ~1U)
67
68/*
69 * Flags for library internal use.  These use the upper 16 bits of a
70 * flags field.
71 */
72#define	LIBELF_F_MALLOCED	0x010000 /* whether data was malloc'ed */
73#define	LIBELF_F_MMAP		0x020000 /* whether e_rawfile was mmap'ed */
74#define	LIBELF_F_SHDRS_LOADED	0x040000 /* whether all shdrs were read in */
75
76struct _Elf {
77	int		e_activations;	/* activation count */
78	Elf_Arhdr	*e_arhdr;	/* header for archive members */
79	unsigned int	e_byteorder;	/* ELFDATA* */
80	int		e_class;	/* ELFCLASS*  */
81	Elf_Cmd		e_cmd;		/* ELF_C_* used at creation time */
82	int		e_fd;		/* associated file descriptor */
83	unsigned int	e_flags;	/* ELF_F_*, LIBELF_F_* flags */
84	Elf_Kind	e_kind;		/* ELF_K_* */
85	Elf		*e_parent; 	/* non-NULL for archive members */
86	char	 	*e_rawfile;	/* uninterpreted bytes */
87	size_t		e_rawsize;	/* size of uninterpreted bytes */
88	unsigned int	e_version;	/* file version */
89
90	union {
91		struct {		/* ar(1) archives */
92			off_t	e_next;	/* set by elf_rand()/elf_next() */
93			int	e_nchildren;
94			char	*e_rawstrtab;	/* file name strings */
95			size_t	e_rawstrtabsz;
96			char	*e_rawsymtab;	/* symbol table */
97			size_t	e_rawsymtabsz;
98			Elf_Arsym *e_symtab;
99			size_t	e_symtabsz;
100		} e_ar;
101		struct {		/* regular ELF files */
102			union {
103				Elf32_Ehdr *e_ehdr32;
104				Elf64_Ehdr *e_ehdr64;
105			} e_ehdr;
106			union {
107				Elf32_Phdr *e_phdr32;
108				Elf64_Phdr *e_phdr64;
109			} e_phdr;
110			STAILQ_HEAD(, _Elf_Scn)	e_scn;	/* section list */
111			size_t	e_nphdr;	/* number of Phdr entries */
112			size_t	e_nscn;		/* number of sections */
113			size_t	e_strndx;	/* string table section index */
114		} e_elf;
115	} e_u;
116};
117
118struct _Elf_Scn {
119	union {
120		Elf32_Shdr	s_shdr32;
121		Elf64_Shdr	s_shdr64;
122	} s_shdr;
123	STAILQ_HEAD(, _Elf_Data) s_data;	/* list of Elf_Data descriptors */
124	STAILQ_HEAD(, _Elf_Data) s_rawdata;	/* raw data for this section */
125	STAILQ_ENTRY(_Elf_Scn) s_next;
126	struct _Elf	*s_elf;		/* parent ELF descriptor */
127	unsigned int	s_flags;	/* flags for the section as a whole */
128	size_t		s_ndx;		/* index# for this section */
129	uint64_t	s_offset;	/* managed by elf_update() */
130	uint64_t	s_rawoff;	/* original offset in the file */
131	uint64_t	s_size;		/* managed by elf_update() */
132};
133
134
135enum {
136	ELF_TOFILE,
137	ELF_TOMEMORY
138};
139
140#define	LIBELF_COPY_U32(DST,SRC,NAME)	do {		\
141		if ((SRC)->NAME > UINT_MAX) {		\
142			LIBELF_SET_ERROR(RANGE, 0);	\
143			return (0);			\
144		}					\
145		(DST)->NAME = (SRC)->NAME;		\
146	} while (0)
147
148#define	LIBELF_COPY_S32(DST,SRC,NAME)	do {		\
149		if ((SRC)->NAME > INT_MAX ||		\
150		    (SRC)->NAME < INT_MIN) {		\
151			LIBELF_SET_ERROR(RANGE, 0);	\
152			return (0);			\
153		}					\
154		(DST)->NAME = (SRC)->NAME;		\
155	} while (0)
156
157
158/*
159 * Prototypes
160 */
161
162Elf_Data *_libelf_allocate_data(Elf_Scn *_s);
163Elf	*_libelf_allocate_elf(void);
164Elf_Scn	*_libelf_allocate_scn(Elf *_e, size_t _ndx);
165Elf_Arhdr *_libelf_ar_gethdr(Elf *_e);
166Elf	*_libelf_ar_open(Elf *_e);
167Elf	*_libelf_ar_open_member(int _fd, Elf_Cmd _c, Elf *_ar);
168int	_libelf_ar_get_member(char *_s, size_t _sz, int _base, size_t *_ret);
169char	*_libelf_ar_get_string(const char *_buf, size_t _sz, int _rawname);
170char	*_libelf_ar_get_name(char *_buf, size_t _sz, Elf *_e);
171int	_libelf_ar_get_number(char *_buf, size_t _sz, int _base, size_t *_ret);
172Elf_Arsym *_libelf_ar_process_symtab(Elf *_ar, size_t *_dst);
173unsigned long _libelf_checksum(Elf *_e, int _elfclass);
174void	*_libelf_ehdr(Elf *_e, int _elfclass, int _allocate);
175int	_libelf_falign(Elf_Type _t, int _elfclass);
176size_t	_libelf_fsize(Elf_Type _t, int _elfclass, unsigned int _version,
177    size_t count);
178int	(*_libelf_get_translator(Elf_Type _t, int _direction, int _elfclass))
179	    (char *_dst, size_t dsz, char *_src, size_t _cnt, int _byteswap);
180void	*_libelf_getphdr(Elf *_e, int _elfclass);
181void	*_libelf_getshdr(Elf_Scn *_scn, int _elfclass);
182void	_libelf_init_elf(Elf *_e, Elf_Kind _kind);
183int	_libelf_load_scn(Elf *e, void *ehdr);
184int	_libelf_malign(Elf_Type _t, int _elfclass);
185size_t	_libelf_msize(Elf_Type _t, int _elfclass, unsigned int _version);
186void	*_libelf_newphdr(Elf *_e, int _elfclass, size_t _count);
187Elf_Data *_libelf_release_data(Elf_Data *_d);
188Elf	*_libelf_release_elf(Elf *_e);
189Elf_Scn	*_libelf_release_scn(Elf_Scn *_s);
190int	_libelf_setphnum(Elf *_e, void *_eh, int _elfclass, size_t _phnum);
191int	_libelf_setshnum(Elf *_e, void *_eh, int _elfclass, size_t _shnum);
192int	_libelf_setshstrndx(Elf *_e, void *_eh, int _elfclass,
193    size_t _shstrndx);
194Elf_Data *_libelf_xlate(Elf_Data *_d, const Elf_Data *_s,
195    unsigned int _encoding, int _elfclass, int _direction);
196int	_libelf_xlate_shtype(uint32_t _sht);
197
198#endif	/* __LIBELF_H_ */
199