1/* Transformation functions for ELF data types.
2   Copyright (C) 1998,1999,2000,2002,2004,2005,2006,2007 Red Hat, Inc.
3   This file is part of elfutils.
4   Written by Ulrich Drepper <drepper@redhat.com>, 1998.
5
6   This file is free software; you can redistribute it and/or modify
7   it under the terms of either
8
9     * the GNU Lesser General Public License as published by the Free
10       Software Foundation; either version 3 of the License, or (at
11       your option) any later version
12
13   or
14
15     * the GNU General Public License as published by the Free
16       Software Foundation; either version 2 of the License, or (at
17       your option) any later version
18
19   or both in parallel, as here.
20
21   elfutils is distributed in the hope that it will be useful, but
22   WITHOUT ANY WARRANTY; without even the implied warranty of
23   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
24   General Public License for more details.
25
26   You should have received copies of the GNU General Public License and
27   the GNU Lesser General Public License along with this program.  If
28   not, see <http://www.gnu.org/licenses/>.  */
29
30#ifdef HAVE_CONFIG_H
31# include <config.h>
32#endif
33
34#include <byteswap.h>
35#include <stdint.h>
36#include <string.h>
37#include <stdlib.h>
38
39#include "libelfP.h"
40
41#ifndef LIBELFBITS
42# define LIBELFBITS	32
43#endif
44
45
46/* Well, what shall I say.  Nothing to do here.  */
47#define elf_cvt_Byte(dest, src, n) \
48  (__builtin_constant_p (n) && (n) == 1					      \
49   ? (void) (*((char *) (dest)) = *((char *) (src)))			      \
50   : Elf32_cvt_Byte (dest, src, n))
51static void
52(elf_cvt_Byte) (void *dest, const void *src, size_t n,
53		int encode __attribute__ ((unused)))
54{
55  memmove (dest, src, n);
56}
57
58
59/* We'll optimize the definition of the conversion functions here a
60   bit.  We need only functions for 16, 32, and 64 bits.  The
61   functions referenced in the table will be aliases for one of these
62   functions.  Which one is decided by the ELFxx_FSZ_type.  */
63
64#if ALLOW_UNALIGNED
65
66#define FETCH(Bits, ptr)	(*(const uint##Bits##_t *) ptr)
67#define STORE(Bits, ptr, val)	(*(uint##Bits##_t *) ptr = val)
68
69#else
70
71union unaligned
72  {
73    uint16_t u16;
74    uint32_t u32;
75    uint64_t u64;
76  } __attribute__ ((packed));
77
78#define FETCH(Bits, ptr)	(((const union unaligned *) ptr)->u##Bits)
79#define STORE(Bits, ptr, val)	(((union unaligned *) ptr)->u##Bits = val)
80
81#endif
82
83/* Now define the conversion functions for the basic types.  We use here
84   the fact that file and memory types are the same and that we have the
85   ELFxx_FSZ_* macros.
86
87   At the same time we define inline functions which we will use to
88   convert the complex types.  */
89#define FUNDAMENTAL(NAME, Name, Bits) \
90  INLINE2 (ELFW2(Bits,FSZ_##NAME), ElfW2(Bits,cvt_##Name), ElfW2(Bits,Name))
91#define INLINE2(Bytes, FName, TName) \
92  INLINE3 (Bytes, FName, TName)
93#define INLINE3(Bytes, FName, TName)					      \
94  static inline void FName##1 (void *dest, const void *ptr)		      \
95  {									      \
96    switch (Bytes)							      \
97      {									      \
98      case 2: STORE (16, dest, bswap_16 (FETCH (16, ptr))); break;	      \
99      case 4: STORE (32, dest, bswap_32 (FETCH (32, ptr))); break;	      \
100      case 8: STORE (64, dest, bswap_64 (FETCH (64, ptr))); break;	      \
101      default:								      \
102	abort ();							      \
103      }									      \
104  }									      \
105									      \
106  static void FName (void *dest, const void *ptr, size_t len,		      \
107		     int encode __attribute__ ((unused)))		      \
108  {									      \
109    size_t n = len / sizeof (TName);					      \
110    if (dest < ptr)							      \
111      while (n-- > 0)							      \
112	{								      \
113	  FName##1 (dest, ptr);						      \
114	  dest += Bytes;						      \
115	  ptr += Bytes;							      \
116	}								      \
117    else								      \
118      {									      \
119	dest += len;							      \
120	ptr += len;							      \
121	while (n-- > 0)							      \
122	  {								      \
123	    ptr -= Bytes;						      \
124	    dest -= Bytes;						      \
125	    FName##1 (dest, ptr);					      \
126	  }								      \
127      }									      \
128  }
129
130
131/* Now the tricky part: define the transformation functions for the
132   complex types.  We will use the definitions of the types in
133   abstract.h.  */
134#define START(Bits, Name, EName) \
135  static void								      \
136  ElfW2 (Bits, cvt_##Name) (void *dest, const void *src, size_t len,	      \
137			    int encode __attribute__ ((unused)))	      \
138  { ElfW2(Bits, Name) *tdest = (ElfW2(Bits, Name) *) dest;		      \
139    ElfW2(Bits, Name) *tsrc = (ElfW2(Bits, Name) *) src;		      \
140    size_t n;								      \
141    for (n = len / sizeof (ElfW2(Bits, Name)); n > 0; ++tdest, ++tsrc, --n) {
142#define END(Bits, Name) } }
143#define TYPE_EXTRA(Code)
144#define TYPE_XLATE(Code) Code
145#define TYPE_NAME(Type, Name) TYPE_NAME2 (Type, Name)
146#define TYPE_NAME2(Type, Name) Type##1 (&tdest->Name, &tsrc->Name);
147#define TYPE(Name, Bits) TYPE2 (Name, Bits)
148#define TYPE2(Name, Bits) TYPE3 (Name##Bits)
149#define TYPE3(Name) Name (cvt_)
150
151/* Signal that we are generating conversion functions.  */
152#define GENERATE_CONVERSION
153
154/* First generate the 32-bit conversion functions.  */
155#define LIBELFBITS 32
156#include "gelf_xlate.h"
157
158/* Now generate the 64-bit conversion functions.  */
159#define LIBELFBITS 64
160#include "gelf_xlate.h"
161
162
163/* We have a few functions which we must create by hand since the sections
164   do not contain records of only one type.  */
165#include "version_xlate.h"
166#include "gnuhash_xlate.h"
167#include "note_xlate.h"
168
169
170/* Now the externally visible table with the function pointers.  */
171const xfct_t __elf_xfctstom[EV_NUM - 1][EV_NUM - 1][ELFCLASSNUM - 1][ELF_T_NUM] =
172{
173  [EV_CURRENT - 1] = {
174    [EV_CURRENT - 1] = {
175      [ELFCLASS32 - 1] = {
176#define define_xfcts(Bits) \
177	[ELF_T_BYTE]	= elf_cvt_Byte,					      \
178	[ELF_T_ADDR]	= ElfW2(Bits, cvt_Addr),			      \
179	[ELF_T_DYN]	= ElfW2(Bits, cvt_Dyn),				      \
180	[ELF_T_EHDR]	= ElfW2(Bits, cvt_Ehdr),			      \
181	[ELF_T_HALF]	= ElfW2(Bits, cvt_Half),			      \
182	[ELF_T_OFF]	= ElfW2(Bits, cvt_Off),				      \
183	[ELF_T_PHDR]	= ElfW2(Bits, cvt_Phdr),			      \
184	[ELF_T_RELA]	= ElfW2(Bits, cvt_Rela),			      \
185	[ELF_T_REL]	= ElfW2(Bits, cvt_Rel),				      \
186	[ELF_T_SHDR]	= ElfW2(Bits, cvt_Shdr),			      \
187	[ELF_T_SWORD]	= ElfW2(Bits, cvt_Sword),			      \
188	[ELF_T_SYM]	= ElfW2(Bits, cvt_Sym),				      \
189	[ELF_T_WORD]	= ElfW2(Bits, cvt_Word),			      \
190	[ELF_T_XWORD]	= ElfW2(Bits, cvt_Xword),			      \
191	[ELF_T_SXWORD]	= ElfW2(Bits, cvt_Sxword),			      \
192	[ELF_T_VDEF]	= elf_cvt_Verdef,				      \
193	[ELF_T_VDAUX]	= elf_cvt_Verdef,				      \
194	[ELF_T_VNEED]	= elf_cvt_Verneed,				      \
195	[ELF_T_VNAUX]	= elf_cvt_Verneed,				      \
196	[ELF_T_NHDR]	= elf_cvt_note,					      \
197	[ELF_T_SYMINFO] = ElfW2(Bits, cvt_Syminfo),			      \
198	[ELF_T_MOVE]	= ElfW2(Bits, cvt_Move),			      \
199	[ELF_T_LIB]	= ElfW2(Bits, cvt_Lib),				      \
200	[ELF_T_AUXV]	= ElfW2(Bits, cvt_auxv_t)
201        define_xfcts (32),
202	[ELF_T_GNUHASH] = Elf32_cvt_Word
203      },
204      [ELFCLASS64 - 1] = {
205	define_xfcts (64),
206	[ELF_T_GNUHASH] = elf_cvt_gnuhash
207      }
208    }
209  }
210};
211/* For now we only handle the case where the memory representation is the
212   same as the file representation.  Should this change we have to define
213   separate functions.  For now reuse them.  */
214strong_alias (__elf_xfctstom, __elf_xfctstof)
215