1 /*
2  * Copyright (c) 2004 Russ Cox.  See LICENSE.
3  */
4 
5 /* /home/rsc/papers/elfXXelf.pdf */
6 
7 typedef struct Elf Elf;
8 typedef struct ElfHdr ElfHdr;
9 typedef struct ElfSect ElfSect;
10 typedef struct ElfProg ElfProg;
11 typedef struct ElfNote ElfNote;
12 typedef struct ElfSym ElfSym;
13 
14 enum
15 {
16 	ElfClassNone = 0,
17 	ElfClass32,
18 	ElfClass64,
19 
20 	ElfDataNone = 0,
21 	ElfDataLsb,
22 	ElfDataMsb,
23 
24 	ElfTypeNone = 0,
25 	ElfTypeRelocatable,
26 	ElfTypeExecutable,
27 	ElfTypeSharedObject,
28 	ElfTypeCore,
29 	/* 0xFF00 - 0xFFFF reserved for processor-specific types */
30 
31 	ElfMachNone = 0,
32 	ElfMach32100,		/* AT&T WE 32100 */
33 	ElfMachSparc,		/* SPARC */
34 	ElfMach386,		/* Intel 80386 */
35 	ElfMach68000,		/* Motorola 68000 */
36 	ElfMach88000,		/* Motorola 88000 */
37 	ElfMach486,		/* Intel 80486, no longer used */
38 	ElfMach860,		/* Intel 80860 */
39 	ElfMachMips,		/* MIPS RS3000 */
40 	ElfMachS370,		/* IBM System/370 */
41 	ElfMachMipsLe,	/* MIPS RS3000 LE */
42 	ElfMachParisc = 15,		/* HP PA RISC */
43 	ElfMachVpp500 = 17,	/* Fujitsu VPP500 */
44 	ElfMachSparc32Plus,	/* SPARC V8+ */
45 	ElfMach960,		/* Intel 80960 */
46 	ElfMachPower,		/* PowerPC */
47 	ElfMachPower64,	/* PowerPC 64 */
48 	ElfMachS390,		/* IBM System/390 */
49 	ElfMachV800 = 36,	/* NEC V800 */
50 	ElfMachFr20,		/* Fujitsu FR20 */
51 	ElfMachRh32,		/* TRW RH-32 */
52 	ElfMachRce,		/* Motorola RCE */
53 	ElfMachArm,		/* ARM */
54 	ElfMachAlpha,		/* Digital Alpha */
55 	ElfMachSH,		/* Hitachi SH */
56 	ElfMachSparc9,		/* SPARC V9 */
57 	ElfMachAmd64 = 62,	/* x86-64 */
58 	/* and the list goes on... */
59 
60 	ElfAbiNone = 0,
61 	ElfAbiSystemV = 0,	/* [sic] */
62 	ElfAbiHPUX,
63 	ElfAbiNetBSD,
64 	ElfAbiLinux,
65 	ElfAbiSolaris = 6,
66 	ElfAbiAix,
67 	ElfAbiIrix,
68 	ElfAbiFreeBSD,
69 	ElfAbiTru64,
70 	ElfAbiModesto,
71 	ElfAbiOpenBSD,
72 	ElfAbiARM = 97,
73 	ElfAbiEmbedded = 255,
74 
75 	/* some of sections 0xFF00 - 0xFFFF reserved for various things */
76 	ElfSectNone = 0,
77 	ElfSectProgbits,
78 	ElfSectSymtab,
79 	ElfSectStrtab,
80 	ElfSectRela,
81 	ElfSectHash,
82 	ElfSectDynamic,
83 	ElfSectNote,
84 	ElfSectNobits,
85 	ElfSectRel,
86 	ElfSectShlib,
87 	ElfSectDynsym,
88 
89 	ElfSectFlagWrite = 0x1,
90 	ElfSectFlagAlloc = 0x2,
91 	ElfSectFlagExec = 0x4,
92 	/* 0xF0000000 are reserved for processor specific */
93 
94 	ElfSymBindLocal = 0,
95 	ElfSymBindGlobal,
96 	ElfSymBindWeak,
97 	/* 13-15 reserved */
98 
99 	ElfSymTypeNone = 0,
100 	ElfSymTypeObject,
101 	ElfSymTypeFunc,
102 	ElfSymTypeSection,
103 	ElfSymTypeFile,
104 	/* 13-15 reserved */
105 
106 	ElfSymShnNone = 0,
107 	ElfSymShnAbs = 0xFFF1,
108 	ElfSymShnCommon = 0xFFF2,
109 	/* 0xFF00-0xFF1F reserved for processors */
110 	/* 0xFF20-0xFF3F reserved for operating systems */
111 
112 	ElfProgNone = 0,
113 	ElfProgLoad,
114 	ElfProgDynamic,
115 	ElfProgInterp,
116 	ElfProgNote,
117 	ElfProgShlib,
118 	ElfProgPhdr,
119 
120 	ElfProgFlagExec = 0x1,
121 	ElfProgFlagWrite = 0x2,
122 	ElfProgFlagRead = 0x4,
123 
124 	ElfNotePrStatus = 1,
125 	ElfNotePrFpreg = 2,
126 	ElfNotePrPsinfo = 3,
127 	ElfNotePrTaskstruct = 4,
128 	ElfNotePrAuxv = 6,
129 	ElfNotePrXfpreg = 0x46e62b7f	/* for gdb/386 */
130 };
131 
132 struct ElfHdr
133 {
134 	uchar	magic[4];
135 	uchar	class;
136 	uchar	encoding;
137 	uchar	version;
138 	uchar	abi;
139 	uchar	abiversion;
140 	u32int	type;
141 	u32int	machine;
142 	u64int	entry;
143 	u64int	phoff;
144 	u64int	shoff;
145 	u32int	flags;
146 	u32int	ehsize;
147 	u32int	phentsize;
148 	u32int	phnum;
149 	u32int	shentsize;
150 	u32int	shnum;
151 	u32int	shstrndx;
152 	u16int	(*e2)(uchar*);
153 	u32int	(*e4)(uchar*);
154 	u64int	(*e8)(uchar*);
155 };
156 
157 struct ElfSect
158 {
159 	char		*name;
160 	u32int	type;
161 	u64int	flags;
162 	u64int	addr;
163 	u64int	offset;
164 	u64int	size;
165 	u32int	link;
166 	u32int	info;
167 	u64int	align;
168 	u64int	entsize;
169 	uchar	*base;
170 };
171 
172 struct ElfProg
173 {
174 	u32int	type;
175 	u64int	offset;
176 	u64int	vaddr;
177 	u64int	paddr;
178 	u64int	filesz;
179 	u64int	memsz;
180 	u32int	flags;
181 	u64int	align;
182 };
183 
184 struct ElfNote
185 {
186 	u32int	namesz;
187 	u32int	descsz;
188 	u32int	type;
189 	char	*name;
190 	uchar	*desc;
191 	u32int	offset;	/* in-memory only */
192 };
193 
194 struct ElfSym
195 {
196 	char*	name;
197 	u64int	value;
198 	u64int	size;
199 	uchar	bind;
200 	uchar	type;
201 	uchar	other;
202 	u16int	shndx;
203 };
204 
205 struct Elf
206 {
207 	int		fd;
208 	ElfHdr	hdr;
209 	ElfSect	*sect;
210 	uint		nsect;
211 	ElfProg	*prog;
212 	uint		nprog;
213 	char		*shstrtab;
214 
215 	int		nsymtab;
216 	ElfSect	*symtab;
217 	ElfSect	*symstr;
218 	int		ndynsym;
219 	ElfSect	*dynsym;
220 	ElfSect	*dynstr;
221 	ElfSect	*bss;
222 	ulong	dynamic;		/* offset to elf dynamic crap */
223 
224 	int		(*coreregs)(Elf*, ElfNote*, uchar**);
225 	int		(*corecmd)(Elf*, ElfNote*, char**);
226 };
227 
228 Elf*	elfopen(char*);
229 Elf*	elfinit(int);
230 ElfSect *elfsection(Elf*, char*);
231 void	elfclose(Elf*);
232 int	elfsym(Elf*, int, ElfSym*);
233 int	elfsymlookup(Elf*, char*, ulong*);
234 int	elfmap(Elf*, ElfSect*);
235 
236 struct Fhdr;
237 void	elfcorelinux386(struct Fhdr*, Elf*, ElfNote*);
238 void	elfcorefreebsd386(struct Fhdr*, Elf*, ElfNote*);
239 void	elfcorefreebsdamd64(struct Fhdr*, Elf*, ElfNote*);
240 void	elfdl386mapdl(int);