1/*-
2 * Copyright (c) 2006,2008-2011 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 * $Id: _libelf.h,v 1.3 2020/05/18 06:46:23 jsg Exp $
27 */
28
29#ifndef	__LIBELF_H_
30#define	__LIBELF_H_
31
32#include <sys/queue.h>
33
34#include "_libelf_config.h"
35
36#include "_elftc.h"
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	unsigned 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_ERROR(E, O) (((E) & LIBELF_ELF_ERROR_MASK) |	\
62	((O) << LIBELF_OS_ERROR_SHIFT))
63
64#define	LIBELF_SET_ERROR(E, O) do {					\
65		LIBELF_PRIVATE(error) = LIBELF_ERROR(ELF_E_##E, (O));	\
66	} while (0)
67
68#define	LIBELF_ADJUST_AR_SIZE(S)	(((S) + 1U) & ~1U)
69
70/*
71 * Flags for library internal use.  These use the upper 16 bits of the
72 * `e_flags' field.
73 */
74#define	LIBELF_F_API_MASK	0x00FFFFU  /* Flags defined by the API. */
75#define	LIBELF_F_AR_HEADER	0x010000U  /* translated header available */
76#define	LIBELF_F_AR_VARIANT_SVR4 0x020000U /* BSD style ar(1) archive */
77#define	LIBELF_F_DATA_MALLOCED	0x040000U /* whether data was malloc'ed */
78#define	LIBELF_F_RAWFILE_MALLOC	0x080000U /* whether e_rawfile was malloc'ed */
79#define	LIBELF_F_RAWFILE_MMAP	0x100000U /* whether e_rawfile was mmap'ed */
80#define	LIBELF_F_SHDRS_LOADED	0x200000U /* whether all shdrs were read in */
81#define	LIBELF_F_SPECIAL_FILE	0x400000U /* non-regular file */
82
83struct _Elf {
84	int		e_activations;	/* activation count */
85	unsigned int	e_byteorder;	/* ELFDATA* */
86	int		e_class;	/* ELFCLASS*  */
87	Elf_Cmd		e_cmd;		/* ELF_C_* used at creation time */
88	int		e_fd;		/* associated file descriptor */
89	unsigned int	e_flags;	/* ELF_F_* & LIBELF_F_* flags */
90	Elf_Kind	e_kind;		/* ELF_K_* */
91	Elf		*e_parent; 	/* non-NULL for archive members */
92	unsigned char	*e_rawfile;	/* uninterpreted bytes */
93	off_t		e_rawsize;	/* size of uninterpreted bytes */
94	unsigned int	e_version;	/* file version */
95
96	/*
97	 * Header information for archive members.  See the
98	 * LIBELF_F_AR_HEADER flag.
99	 */
100	union {
101		Elf_Arhdr	*e_arhdr;	/* translated header */
102		unsigned char	*e_rawhdr;	/* untranslated header */
103	} e_hdr;
104
105	union {
106		struct {		/* ar(1) archives */
107			off_t	e_next;	/* set by elf_rand()/elf_next() */
108			int	e_nchildren;
109			unsigned char *e_rawstrtab; /* file name strings */
110			size_t	e_rawstrtabsz;
111			unsigned char *e_rawsymtab;	/* symbol table */
112			size_t	e_rawsymtabsz;
113			Elf_Arsym *e_symtab;
114			size_t	e_symtabsz;
115		} e_ar;
116		struct {		/* regular ELF files */
117			union {
118				Elf32_Ehdr *e_ehdr32;
119				Elf64_Ehdr *e_ehdr64;
120			} e_ehdr;
121			union {
122				Elf32_Phdr *e_phdr32;
123				Elf64_Phdr *e_phdr64;
124			} e_phdr;
125			STAILQ_HEAD(, _Elf_Scn)	e_scn;	/* section list */
126			size_t	e_nphdr;	/* number of Phdr entries */
127			size_t	e_nscn;		/* number of sections */
128			size_t	e_strndx;	/* string table section index */
129		} e_elf;
130	} e_u;
131};
132
133/*
134 * The internal descriptor wrapping the "Elf_Data" type.
135 */
136struct _Libelf_Data {
137	Elf_Data	d_data;		/* The exported descriptor. */
138	Elf_Scn		*d_scn;		/* The containing section */
139	unsigned int	d_flags;
140	STAILQ_ENTRY(_Libelf_Data) d_next;
141};
142
143struct _Elf_Scn {
144	union {
145		Elf32_Shdr	s_shdr32;
146		Elf64_Shdr	s_shdr64;
147	} s_shdr;
148	STAILQ_HEAD(, _Libelf_Data) s_data;	/* translated data */
149	STAILQ_HEAD(, _Libelf_Data) s_rawdata;	/* raw data */
150	STAILQ_ENTRY(_Elf_Scn) s_next;
151	struct _Elf	*s_elf;		/* parent ELF descriptor */
152	unsigned int	s_flags;	/* flags for the section as a whole */
153	size_t		s_ndx;		/* index# for this section */
154	uint64_t	s_offset;	/* managed by elf_update() */
155	uint64_t	s_rawoff;	/* original offset in the file */
156	uint64_t	s_size;		/* managed by elf_update() */
157};
158
159
160enum {
161	ELF_TOFILE,
162	ELF_TOMEMORY
163};
164
165
166/*
167 * The LIBELF_COPY macros are used to copy fields from a GElf_*
168 * structure to their 32-bit counterparts, while checking for out of
169 * range values.
170 *
171 * - LIBELF_COPY_U32 :: copy an unsigned 32 bit field.
172 * - LIBELF_COPY_S32 :: copy a signed 32 bit field.
173 */
174
175#define	LIBELF_COPY_U32(DST, SRC, NAME)	do {			\
176		if ((SRC)->NAME > UINT32_MAX) {			\
177			LIBELF_SET_ERROR(RANGE, 0);		\
178			return (0);				\
179		}						\
180		(DST)->NAME = (SRC)->NAME & 0xFFFFFFFFU;	\
181	} while (0)
182
183#define	LIBELF_COPY_S32(DST, SRC, NAME)	do {			\
184		if ((SRC)->NAME > INT32_MAX ||			\
185		    (SRC)->NAME < INT32_MIN) {			\
186			LIBELF_SET_ERROR(RANGE, 0);		\
187			return (0);				\
188		}						\
189		(DST)->NAME = (int32_t) (SRC)->NAME;		\
190	} while (0)
191
192
193/*
194 * Function Prototypes.
195 */
196
197typedef int _libelf_translator_function(unsigned char *_dst, size_t dsz,
198    unsigned char *_src, size_t _cnt, int _byteswap);
199
200#ifdef __cplusplus
201extern "C" {
202#endif
203struct _Libelf_Data *_libelf_allocate_data(Elf_Scn *_s);
204Elf	*_libelf_allocate_elf(void);
205Elf_Scn	*_libelf_allocate_scn(Elf *_e, size_t _ndx);
206Elf_Arhdr *_libelf_ar_gethdr(Elf *_e);
207Elf	*_libelf_ar_open(Elf *_e, int _reporterror);
208Elf	*_libelf_ar_open_member(int _fd, Elf_Cmd _c, Elf *_ar);
209Elf_Arsym *_libelf_ar_process_bsd_symtab(Elf *_ar, size_t *_dst);
210Elf_Arsym *_libelf_ar_process_svr4_symtab(Elf *_ar, size_t *_dst);
211long	 _libelf_checksum(Elf *_e, int _elfclass);
212void	*_libelf_ehdr(Elf *_e, int _elfclass, int _allocate);
213int	_libelf_elfmachine(Elf *_e);
214unsigned int _libelf_falign(Elf_Type _t, int _elfclass);
215size_t	_libelf_fsize(Elf_Type _t, int _elfclass, unsigned int _version,
216    size_t count);
217_libelf_translator_function *_libelf_get_translator(Elf_Type _t,
218    int _direction, int _elfclass, int _elfmachine);
219void	*_libelf_getphdr(Elf *_e, int _elfclass);
220void	*_libelf_getshdr(Elf_Scn *_scn, int _elfclass);
221void	_libelf_init_elf(Elf *_e, Elf_Kind _kind);
222int	_libelf_load_section_headers(Elf *e, void *ehdr);
223unsigned int _libelf_malign(Elf_Type _t, int _elfclass);
224Elf	*_libelf_memory(unsigned char *_image, size_t _sz, int _reporterror);
225size_t	_libelf_msize(Elf_Type _t, int _elfclass, unsigned int _version);
226void	*_libelf_newphdr(Elf *_e, int _elfclass, size_t _count);
227Elf	*_libelf_open_object(int _fd, Elf_Cmd _c, int _reporterror);
228struct _Libelf_Data *_libelf_release_data(struct _Libelf_Data *_d);
229void	_libelf_release_elf(Elf *_e);
230Elf_Scn	*_libelf_release_scn(Elf_Scn *_s);
231int	_libelf_setphnum(Elf *_e, void *_eh, int _elfclass, size_t _phnum);
232int	_libelf_setshnum(Elf *_e, void *_eh, int _elfclass, size_t _shnum);
233int	_libelf_setshstrndx(Elf *_e, void *_eh, int _elfclass,
234    size_t _shstrndx);
235Elf_Data *_libelf_xlate(Elf_Data *_d, const Elf_Data *_s,
236    unsigned int _encoding, int _elfclass, int _elfmachine, int _direction);
237int	_libelf_xlate_shtype(uint32_t _sht);
238#ifdef __cplusplus
239}
240#endif
241
242#endif	/* __LIBELF_H_ */
243