[dragonfly.git] / libexec / rtld-elf / rtld.h

/*-
 * Copyright 1996, 1997, 1998, 1999, 2000 John D. Polstra.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * $FreeBSD: src/libexec/rtld-elf/rtld.h,v 1.15.2.6 2003/02/20 20:42:46 kan Exp $
 */

#ifndef RTLD_H /* { */
#define RTLD_H 1

#include <machine/elf.h>
#include <sys/types.h>
#include <sys/queue.h>

#include <elf-hints.h>
#include <link.h>
#include <stddef.h>

#include "rtld_machdep.h"

#ifndef STANDARD_LIBRARY_PATH
#define STANDARD_LIBRARY_PATH	"/usr/lib"
#endif

#define NEW(type)	((type *) xmalloc(sizeof(type)))
#define CNEW(type)	((type *) xcalloc(sizeof(type)))

/* We might as well do booleans like C++. */
typedef unsigned char bool;
#define false	0
#define true	1

extern size_t tls_last_offset;
extern size_t tls_last_size;
extern size_t tls_static_space;
extern int tls_dtv_generation;
extern int tls_max_index;

struct stat;
struct Struct_Obj_Entry;

/* Lists of shared objects */
typedef struct Struct_Objlist_Entry {
    STAILQ_ENTRY(Struct_Objlist_Entry) link;
    struct Struct_Obj_Entry *obj;
} Objlist_Entry;

typedef STAILQ_HEAD(Struct_Objlist, Struct_Objlist_Entry) Objlist;

/* Types of init and fini functions */
typedef void (*InitFunc)(void);

/* Lists of shared object dependencies */
typedef struct Struct_Needed_Entry {
    struct Struct_Needed_Entry *next;
    struct Struct_Obj_Entry *obj;
    unsigned long name;		/* Offset of name in string table */
} Needed_Entry;

/* Lock object */
typedef struct Struct_LockInfo {
    void *context;		/* Client context for creating locks */
    void *thelock;		/* The one big lock */
    /* Debugging aids. */
    volatile int rcount;	/* Number of readers holding lock */
    volatile int wcount;	/* Number of writers holding lock */
    /* Methods */
    void *(*lock_create)(void *context);
    void (*rlock_acquire)(void *lock);
    void (*wlock_acquire)(void *lock);
    void (*rlock_release)(void *lock);
    void (*wlock_release)(void *lock);
    void (*lock_destroy)(void *lock);
    void (*context_destroy)(void *context);
} LockInfo;

/*
 * Shared object descriptor.
 *
 * Items marked with "(%)" are dynamically allocated, and must be freed
 * when the structure is destroyed.
 *
 * CAUTION: It appears that the JDK port peeks into these structures.
 * It looks at "next" and "mapbase" at least.  Don't add new members
 * near the front, until this can be straightened out.
 */
typedef struct Struct_Obj_Entry {
    /*
     * These two items have to be set right for compatibility with the
     * original ElfKit crt1.o.
     */
    Elf_Size magic;		/* Magic number (sanity check) */
    Elf_Size version;		/* Version number of struct format */

    struct Struct_Obj_Entry *next;
    char *path;			/* Pathname of underlying file (%) */
    char *origin_path;		/* Directory path of origin file */
    int refcount;
    int dl_refcount;		/* Number of times loaded by dlopen */

    /* These items are computed by map_object() or by digest_phdr(). */
    caddr_t mapbase;		/* Base address of mapped region */
    size_t mapsize;		/* Size of mapped region in bytes */
    size_t textsize;		/* Size of text segment in bytes */
    Elf_Addr vaddrbase;		/* Base address in shared object file */
    caddr_t relocbase;		/* Relocation constant = mapbase - vaddrbase */
    const Elf_Dyn *dynamic;	/* Dynamic section */
    caddr_t entry;		/* Entry point */
    const Elf_Phdr *phdr;	/* Program header if it is mapped, else NULL */
    size_t phsize;		/* Size of program header in bytes */
    const char *interp;		/* Pathname of the interpreter, if any */

    /* TLS information */
    int tlsindex;		/* Index in DTV for this module */
    void *tlsinit;		/* Base address of TLS init block */
    size_t tlsinitsize;		/* Size of TLS init block for this module */
    size_t tlssize;		/* Size of TLS block for this module */
    size_t tlsoffset;		/* Offset of static TLS block for this module */
    size_t tlsalign;		/* Alignment of static TLS block */

    /* Items from the dynamic section. */
    Elf_Addr *pltgot;		/* PLT or GOT, depending on architecture */
    const Elf_Rel *rel;		/* Relocation entries */
    unsigned long relsize;	/* Size in bytes of relocation info */
    const Elf_Rela *rela;	/* Relocation entries with addend */
    unsigned long relasize;	/* Size in bytes of addend relocation info */
    const Elf_Rel *pltrel;	/* PLT relocation entries */
    unsigned long pltrelsize;	/* Size in bytes of PLT relocation info */
    const Elf_Rela *pltrela;	/* PLT relocation entries with addend */
    unsigned long pltrelasize;	/* Size in bytes of PLT addend reloc info */
    const Elf_Sym *symtab;	/* Symbol table */
    const char *strtab;		/* String table */
    unsigned long strsize;	/* Size in bytes of string table */

    const Elf_Hashelt *buckets;	/* Hash table buckets array */
    unsigned long nbuckets;	/* Number of buckets */
    const Elf_Hashelt *chains;	/* Hash table chain array */
    unsigned long nchains;	/* Number of chains */

    const char *rpath;		/* Search path specified in object */
    Needed_Entry *needed;	/* Shared objects needed by this one (%) */

    InitFunc init;		/* Initialization function to call */
    InitFunc fini;		/* Termination function to call */

    bool mainprog;		/* True if this is the main program */
    bool rtld;			/* True if this is the dynamic linker */
    bool textrel;		/* True if there are relocations to text seg */
    bool symbolic;		/* True if generated with "-Bsymbolic" */
    bool bind_now;		/* True if all relocations should be made first */
    bool traced;		/* Already printed in ldd trace output */
    bool jmpslots_done;		/* Already have relocated the jump slots */
    bool init_done;		/* Already have added object to init list */
    bool tls_done;		/* Already allocated offset for static TLS */

    struct link_map linkmap;	/* for GDB and dlinfo() */
    Objlist dldags;		/* Object belongs to these dlopened DAGs (%) */
    Objlist dagmembers;		/* DAG has these members (%) */
    dev_t dev;			/* Object's filesystem's device */
    ino_t ino;			/* Object's inode number */
    void *priv;			/* Platform-dependant */
} Obj_Entry;

#define RTLD_MAGIC	0xd550b87a
#define RTLD_VERSION	1

/*
 * Symbol cache entry used during relocation to avoid multiple lookups
 * of the same symbol.
 */
typedef struct Struct_SymCache {
    const Elf_Sym *sym;		/* Symbol table entry */
    const Obj_Entry *obj;	/* Shared object which defines it */
} SymCache;

void		 _rtld_error(const char *, ...) __printflike(1, 2);
Obj_Entry	*map_object(int, const char *, const struct stat *);
void		*xcalloc(size_t);
void		*xmalloc(size_t);
void		*xrealloc(void *, size_t);
char		*xstrdup(const char *);

void		 dump_relocations(Obj_Entry *);
void		 dump_obj_relocations(Obj_Entry *);
void		 dump_Elf_Rel(Obj_Entry *, const Elf_Rel *, u_long);
void		 dump_Elf_Rela(Obj_Entry *, const Elf_Rela *, u_long);

extern Elf_Addr _GLOBAL_OFFSET_TABLE_[];

/*
 * Function declarations.
 */
const char	*basename(const char *);
int		 do_copy_relocations(Obj_Entry *);

unsigned long	 elf_hash(const char *);
const Elf_Sym	 *find_symdef(unsigned long, const Obj_Entry *,
			      const Obj_Entry **, bool, SymCache *);
void		 init_pltgot(Obj_Entry *);
void		 lockdflt_init(LockInfo *);
void		 obj_free(Obj_Entry *);
Obj_Entry	*obj_new(void);
int		 reloc_non_plt(Obj_Entry *, Obj_Entry *);
int		 reloc_plt(Obj_Entry *);
int		 reloc_jmpslots(Obj_Entry *);
void		 _rtld_bind_start(void);
const Elf_Sym	*symlook_obj(const char *, unsigned long, const Obj_Entry *,
			     bool);

void		*tls_get_addr_common(void **, int, size_t);
struct tls_tcb	*allocate_tls(Obj_Entry *);
void		 free_tls(struct tls_tcb *);
void		 *allocate_module_tls(int);
bool		 allocate_tls_offset(Obj_Entry *);
void		 free_tls_offset(Obj_Entry *);
void		 allocate_initial_tls(Obj_Entry *);

#endif /* } */
Commit	Line	Data
984263bc MD	1	/*-
	2	* Copyright 1996, 1997, 1998, 1999, 2000 John D. Polstra.
	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 ``AS IS'' AND ANY EXPRESS OR
	15	* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
	16	* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
	17	* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
	18	* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
	19	* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
	20	* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
	21	* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
	22	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
	23	* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
	24	*
	25	* $FreeBSD: src/libexec/rtld-elf/rtld.h,v 1.15.2.6 2003/02/20 20:42:46 kan Exp $
	26	*/
	27
	28	#ifndef RTLD_H /* { */
	29	#define RTLD_H 1
	30
	31	#include <machine/elf.h>
	32	#include <sys/types.h>
	33	#include <sys/queue.h>
	34
	35	#include <elf-hints.h>
	36	#include <link.h>
	37	#include <stddef.h>
	38
	39	#include "rtld_machdep.h"
	40
	41	#ifndef STANDARD_LIBRARY_PATH
	42	#define STANDARD_LIBRARY_PATH "/usr/lib"
	43	#endif
	44
	45	#define NEW(type) ((type *) xmalloc(sizeof(type)))
	46	#define CNEW(type) ((type *) xcalloc(sizeof(type)))
	47
	48	/* We might as well do booleans like C++. */
	49	typedef unsigned char bool;
	50	#define false 0
	51	#define true 1
	52
55b88cae DX	53	extern size_t tls_last_offset;
	54	extern size_t tls_last_size;
	55	extern size_t tls_static_space;
	56	extern int tls_dtv_generation;
	57	extern int tls_max_index;
	58
984263bc MD	59	struct stat;
	60	struct Struct_Obj_Entry;
	61
	62	/* Lists of shared objects */
	63	typedef struct Struct_Objlist_Entry {
	64	STAILQ_ENTRY(Struct_Objlist_Entry) link;
	65	struct Struct_Obj_Entry *obj;
	66	} Objlist_Entry;
	67
	68	typedef STAILQ_HEAD(Struct_Objlist, Struct_Objlist_Entry) Objlist;
	69
	70	/* Types of init and fini functions */
	71	typedef void (*InitFunc)(void);
	72
	73	/* Lists of shared object dependencies */
	74	typedef struct Struct_Needed_Entry {
	75	struct Struct_Needed_Entry *next;
	76	struct Struct_Obj_Entry *obj;
	77	unsigned long name; /* Offset of name in string table */
	78	} Needed_Entry;
	79
	80	/* Lock object */
	81	typedef struct Struct_LockInfo {
	82	void context; / Client context for creating locks */
	83	void thelock; / The one big lock */
	84	/* Debugging aids. */
	85	volatile int rcount; /* Number of readers holding lock */
	86	volatile int wcount; /* Number of writers holding lock */
	87	/* Methods */
	88	void (lock_create)(void *context);
	89	void (rlock_acquire)(void lock);
	90	void (wlock_acquire)(void lock);
	91	void (rlock_release)(void lock);
	92	void (wlock_release)(void lock);
	93	void (lock_destroy)(void lock);
	94	void (context_destroy)(void context);
	95	} LockInfo;
	96
	97	/*
	98	* Shared object descriptor.
	99	*
	100	* Items marked with "(%)" are dynamically allocated, and must be freed
	101	* when the structure is destroyed.
	102	*
	103	* CAUTION: It appears that the JDK port peeks into these structures.
	104	* It looks at "next" and "mapbase" at least. Don't add new members
	105	* near the front, until this can be straightened out.
	106	*/
	107	typedef struct Struct_Obj_Entry {
	108	/*
	109	* These two items have to be set right for compatibility with the
	110	* original ElfKit crt1.o.
	111	*/
4648abf3 MD	112	Elf_Size magic; /* Magic number (sanity check) */
4648abf3 MD	113	Elf_Size version; /* Version number of struct format */
984263bc MD	114
	115	struct Struct_Obj_Entry *next;
	116	char path; / Pathname of underlying file (%) */
167f7029	117	char origin_path; / Directory path of origin file */
984263bc MD	118	int refcount;
	119	int dl_refcount; /* Number of times loaded by dlopen */
	120
	121	/* These items are computed by map_object() or by digest_phdr(). */
	122	caddr_t mapbase; /* Base address of mapped region */
	123	size_t mapsize; /* Size of mapped region in bytes */
	124	size_t textsize; /* Size of text segment in bytes */
	125	Elf_Addr vaddrbase; /* Base address in shared object file */
	126	caddr_t relocbase; /* Relocation constant = mapbase - vaddrbase */
	127	const Elf_Dyn dynamic; / Dynamic section */
	128	caddr_t entry; /* Entry point */
	129	const Elf_Phdr phdr; / Program header if it is mapped, else NULL */
	130	size_t phsize; /* Size of program header in bytes */
	131	const char interp; / Pathname of the interpreter, if any */
	132
55b88cae DX	133	/* TLS information */
	134	int tlsindex; /* Index in DTV for this module */
	135	void tlsinit; / Base address of TLS init block */
	136	size_t tlsinitsize; /* Size of TLS init block for this module */
	137	size_t tlssize; /* Size of TLS block for this module */
	138	size_t tlsoffset; /* Offset of static TLS block for this module */
	139	size_t tlsalign; /* Alignment of static TLS block */
	140
984263bc MD	141	/* Items from the dynamic section. */
	142	Elf_Addr pltgot; / PLT or GOT, depending on architecture */
	143	const Elf_Rel rel; / Relocation entries */
	144	unsigned long relsize; /* Size in bytes of relocation info */
	145	const Elf_Rela rela; / Relocation entries with addend */
	146	unsigned long relasize; /* Size in bytes of addend relocation info */
	147	const Elf_Rel pltrel; / PLT relocation entries */
	148	unsigned long pltrelsize; /* Size in bytes of PLT relocation info */
	149	const Elf_Rela pltrela; / PLT relocation entries with addend */
	150	unsigned long pltrelasize; /* Size in bytes of PLT addend reloc info */
	151	const Elf_Sym symtab; / Symbol table */
	152	const char strtab; / String table */
	153	unsigned long strsize; /* Size in bytes of string table */
	154
d697cc44	155	const Elf_Hashelt buckets; / Hash table buckets array */
984263bc	156	unsigned long nbuckets; /* Number of buckets */
d697cc44	157	const Elf_Hashelt chains; / Hash table chain array */
984263bc MD	158	unsigned long nchains; /* Number of chains */
	159
	160	const char rpath; / Search path specified in object */
	161	Needed_Entry needed; / Shared objects needed by this one (%) */
	162
	163	InitFunc init; /* Initialization function to call */
	164	InitFunc fini; /* Termination function to call */
	165
	166	bool mainprog; /* True if this is the main program */
	167	bool rtld; /* True if this is the dynamic linker */
	168	bool textrel; /* True if there are relocations to text seg */
	169	bool symbolic; /* True if generated with "-Bsymbolic" */
167f7029	170	bool bind_now; /* True if all relocations should be made first */
984263bc MD	171	bool traced; /* Already printed in ldd trace output */
	172	bool jmpslots_done; /* Already have relocated the jump slots */
	173	bool init_done; /* Already have added object to init list */
55b88cae	174	bool tls_done; /* Already allocated offset for static TLS */
984263bc MD	175
	176	struct link_map linkmap; /* for GDB and dlinfo() */
	177	Objlist dldags; /* Object belongs to these dlopened DAGs (%) */
	178	Objlist dagmembers; /* DAG has these members (%) */
	179	dev_t dev; /* Object's filesystem's device */
	180	ino_t ino; /* Object's inode number */
d697cc44	181	void priv; / Platform-dependant */
984263bc MD	182	} Obj_Entry;
	183
	184	#define RTLD_MAGIC 0xd550b87a
	185	#define RTLD_VERSION 1
	186
	187	/*
	188	* Symbol cache entry used during relocation to avoid multiple lookups
	189	* of the same symbol.
	190	*/
	191	typedef struct Struct_SymCache {
	192	const Elf_Sym sym; / Symbol table entry */
	193	const Obj_Entry obj; / Shared object which defines it */
	194	} SymCache;
	195
7fc47990 JS	196	void _rtld_error(const char *, ...) __printflike(1, 2);
	197	Obj_Entry map_object(int, const char , const struct stat *);
	198	void *xcalloc(size_t);
	199	void *xmalloc(size_t);
	200	void xrealloc(void , size_t);
	201	char xstrdup(const char );
984263bc	202
7fc47990 JS	203	void dump_relocations(Obj_Entry *);
	204	void dump_obj_relocations(Obj_Entry *);
	205	void dump_Elf_Rel(Obj_Entry , const Elf_Rel , u_long);
	206	void dump_Elf_Rela(Obj_Entry , const Elf_Rela , u_long);
4a8d9350	207
4648abf3 MD	208	extern Elf_Addr _GLOBAL_OFFSET_TABLE_[];
4648abf3 MD	209
984263bc MD	210	/*
	211	* Function declarations.
	212	*/
7fc47990 JS	213	const char basename(const char );
7fc47990 JS	214	int do_copy_relocations(Obj_Entry *);
139b8f34	215
7fc47990 JS	216	unsigned long elf_hash(const char *);
	217	const Elf_Sym find_symdef(unsigned long, const Obj_Entry ,
	218	const Obj_Entry *, bool, SymCache );
	219	void init_pltgot(Obj_Entry *);
	220	void lockdflt_init(LockInfo *);
	221	void obj_free(Obj_Entry *);
	222	Obj_Entry *obj_new(void);
	223	int reloc_non_plt(Obj_Entry , Obj_Entry );
	224	int reloc_plt(Obj_Entry *);
	225	int reloc_jmpslots(Obj_Entry *);
	226	void _rtld_bind_start(void);
	227	const Elf_Sym symlook_obj(const char , unsigned long, const Obj_Entry *,
	228	bool);
	229
	230	void tls_get_addr_common(void *, int, size_t);
a1eee96a	231	struct tls_tcb allocate_tls(Obj_Entry );
7fc47990 JS	232	void free_tls(struct tls_tcb *);
	233	void *allocate_module_tls(int);
	234	bool allocate_tls_offset(Obj_Entry *);
	235	void free_tls_offset(Obj_Entry *);
	236	void allocate_initial_tls(Obj_Entry *);
139b8f34	237
984263bc	238	#endif /* } */