src/head/link.h

/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*
 * Copyright 2014 Garrett D'Amore <garrett@damore.org>
 * Copyright (c) 1989, 2010, Oracle and/or its affiliates. All rights reserved.
 */

#ifndef _LINK_H
#define _LINK_H

#include <sys/link.h>

#ifndef _ASM
#include <elf.h>
#include <sys/types.h>
#include <dlfcn.h>
#endif

#ifdef  __cplusplus
extern "C" {
#endif

#ifndef _ASM
/*
 * ld support library calls.
 *
 * These cannot be used in a 32bit large file capable environment because
 * libelf is not large-file safe.  Only define these interfaces if we are not
 * 32bit, or not in the large file environment.
 */
#if !defined(_ILP32) || _FILE_OFFSET_BITS != 64
#include <libelf.h>
extern uint_t   ld_version(uint_t);
extern void ld_input_done(uint_t *);

extern void ld_start(const char *, const Elf32_Half, const char *);
extern void ld_atexit(int);
extern void ld_open(const char **, const char **, int *, int, Elf **,
            Elf *, size_t, const Elf_Kind);
extern void ld_file(const char *, const Elf_Kind, int, Elf *);
extern void ld_input_section(const char *, Elf32_Shdr **, Elf32_Word,
            Elf_Data *, Elf *, uint_t *);
extern void ld_section(const char *, Elf32_Shdr *, Elf32_Word,
            Elf_Data *, Elf *);

#if defined(_LP64) || defined(_LONGLONG_TYPE)
extern void ld_start64(const char *, const Elf64_Half, const char *);
extern void ld_atexit64(int);
extern void ld_open64(const char **, const char **, int *, int, Elf **,
            Elf *, size_t, const Elf_Kind);
extern void ld_file64(const char *, const Elf_Kind, int, Elf *);
extern void ld_input_section64(const char *, Elf64_Shdr **, Elf64_Word,
            Elf_Data *, Elf *, uint_t *);
extern void ld_section64(const char *, Elf64_Shdr *, Elf64_Word,
            Elf_Data *, Elf *);

#endif /* (defined(_LP64) || defined(_LONGLONG_TYPE) */
#endif /* !defined(_ILP32) || _FILE_OFFSET_BITS != 64 */

/*
 * ld_version() version values.
 */
#define LD_SUP_VNONE    0
#define LD_SUP_VERSION1 1
#define LD_SUP_VERSION2 2
#define LD_SUP_VERSION3 3
#define LD_SUP_VCURRENT LD_SUP_VERSION3

/*
 * Flags passed to ld support calls.
 */
#define LD_SUP_DERIVED      0x1 /* derived filename */
#define LD_SUP_INHERITED    0x2 /* file inherited from .so DT_NEEDED */
#define LD_SUP_EXTRACTED    0x4 /* file extracted from archive */
#endif

/*
 * Runtime link-map identifiers.
 */
#define LM_ID_BASE      0x00
#define LM_ID_LDSO      0x01
#define LM_ID_NUM       2

#define LM_ID_BRAND     0xfd    /* brand emulation linkmap objs */
#define LM_ID_NONE      0xfe    /* no link map specified */
#define LM_ID_NEWLM     0xff    /* create a new link-map */

/*
 * Runtime Link-Edit Auditing.
 */
#define LAV_NONE        0
#define LAV_VERSION1        1
#define LAV_VERSION2        2
#define LAV_VERSION3        3
#define LAV_VERSION4        4
#define LAV_VERSION5        5
#define LAV_CURRENT     LAV_VERSION5
#define LAV_NUM         6

/*
 * Flags that can be or'd into the la_objopen() return code
 */
#define LA_FLG_BINDTO       0x0001  /* audit symbinds TO this object */
#define LA_FLG_BINDFROM     0x0002  /* audit symbinding FROM this object */

/*
 * Flags that can be or'd into the 'flags' argument of la_symbind()
 */
#define LA_SYMB_NOPLTENTER  0x0001  /* disable pltenter for this symbol */
#define LA_SYMB_NOPLTEXIT   0x0002  /* disable pltexit for this symbol */
#define LA_SYMB_STRUCTCALL  0x0004  /* this function call passes a */
                    /*  structure as it's return code */
#define LA_SYMB_DLSYM       0x0008  /* this symbol bindings is due to */
                    /*  a call to dlsym() */
#define LA_SYMB_ALTVALUE    0x0010  /* alternate symbol binding returned */
                    /*  by la_symbind() */

/*
 * Flags that describe the object passed to la_objsearch()
 */
#define LA_SER_ORIG     0x001   /* original (needed) name */
#define LA_SER_LIBPATH      0x002   /* LD_LIBRARY_PATH entry prepended */
#define LA_SER_RUNPATH      0x004   /* runpath entry prepended */
#define LA_SER_CONFIG       0x008   /* configuration entry prepended */
#define LA_SER_DEFAULT      0x040   /* default path prepended */
#define LA_SER_SECURE       0x080   /* default (secure) path prepended */

#define LA_SER_MASK     0xfff   /* mask of known flags */

/*
 * Flags that describe the la_activity()
 */
#define LA_ACT_CONSISTENT   0x00    /* add/deletion of objects complete */
#define LA_ACT_ADD      0x01    /* objects being added */
#define LA_ACT_DELETE       0x02    /* objects being deleted */
#define LA_ACT_MAX      3


#ifndef _KERNEL
#ifndef _ASM

#if defined(_LP64)
typedef long    lagreg_t;
#else
typedef int lagreg_t;
#endif

struct _la_sparc_regs {
    lagreg_t    lr_rego0;
    lagreg_t    lr_rego1;
    lagreg_t    lr_rego2;
    lagreg_t    lr_rego3;
    lagreg_t    lr_rego4;
    lagreg_t    lr_rego5;
    lagreg_t    lr_rego6;
    lagreg_t    lr_rego7;
};

#if defined(_LP64)
typedef struct _la_sparc_regs   La_sparcv9_regs;
typedef struct {
    lagreg_t    lr_rsp;
    lagreg_t    lr_rbp;
    lagreg_t    lr_rdi;     /* arg1 */
    lagreg_t    lr_rsi;     /* arg2 */
    lagreg_t    lr_rdx;     /* arg3 */
    lagreg_t    lr_rcx;     /* arg4 */
    lagreg_t    lr_r8;      /* arg5 */
    lagreg_t    lr_r9;      /* arg6 */
} La_amd64_regs;
#else
typedef struct _la_sparc_regs   La_sparcv8_regs;
typedef struct {
    lagreg_t    lr_esp;
    lagreg_t    lr_ebp;
} La_i86_regs;
#endif

#if !defined(_SYS_INT_TYPES_H)
#if defined(_LP64) || defined(_I32LPx)
typedef unsigned long       uintptr_t;
#else
typedef unsigned int        uintptr_t;
#endif
#endif


extern uint_t       la_version(uint_t);
extern void     la_activity(uintptr_t *, uint_t);
extern void     la_preinit(uintptr_t *);
extern char     *la_objsearch(const char *, uintptr_t *, uint_t);
extern uint_t       la_objopen(Link_map *, Lmid_t, uintptr_t *);
extern uint_t       la_objclose(uintptr_t *);
extern int      la_objfilter(uintptr_t *, const char *, uintptr_t *,
                uint_t);
#if defined(_LP64)
extern uintptr_t    la_amd64_pltenter(Elf64_Sym *, uint_t, uintptr_t *,
                uintptr_t *, La_amd64_regs *,   uint_t *,
                const char *);
extern uintptr_t    la_symbind64(Elf64_Sym *, uint_t, uintptr_t *,
                uintptr_t *, uint_t *, const char *);
extern uintptr_t    la_sparcv9_pltenter(Elf64_Sym *, uint_t, uintptr_t *,
                uintptr_t *, La_sparcv9_regs *, uint_t *,
                const char *);
extern uintptr_t    la_pltexit64(Elf64_Sym *, uint_t, uintptr_t *,
                uintptr_t *, uintptr_t, const char *);
#else  /* !defined(_LP64) */
extern uintptr_t    la_symbind32(Elf32_Sym *, uint_t, uintptr_t *,
                uintptr_t *, uint_t *);
extern uintptr_t    la_sparcv8_pltenter(Elf32_Sym *, uint_t, uintptr_t *,
                uintptr_t *, La_sparcv8_regs *, uint_t *);
extern uintptr_t    la_i86_pltenter(Elf32_Sym *, uint_t, uintptr_t *,
                uintptr_t *, La_i86_regs *, uint_t *);
extern uintptr_t    la_pltexit(Elf32_Sym *, uint_t, uintptr_t *,
                uintptr_t *, uintptr_t);
#endif /* _LP64 */

/*
 * The ElfW() macro is a GNU/Linux feature, provided as support for
 * the dl_phdr_info structure used by dl_phdr_iterate(), which also
 * originated under Linux. Given an ELF data type, without the ElfXX_
 * prefix, it supplies the appropriate prefix (Elf32_ or Elf64_) for
 * the ELFCLASS of the code being compiled.
 *
 * Note that ElfW() is not suitable in situations in which the ELFCLASS
 * of the code being compiled does not match that of the objects that
 * code is intended to operate on (e.g. a 32-bit link-editor building
 * a 64-bit object). The macros defined in <sys/machelf.h> are
 * recommended in such cases.
 */
#ifdef _LP64
#define ElfW(type)  Elf64_ ## type
#else
#define ElfW(type)  Elf32_ ## type
#endif

/*
 * The callback function to dl_interate_phdr() receives a pointer
 * to a structure of this type.
 *
 * dlpi_addr is defined such that the address of any segment in
 * the program header array can be calculated as:
 *
 *  addr == info->dlpi_addr + info->dlpi_phdr[x].p_vaddr;
 *
 * It is therefore 0 for ET_EXEC objects, and the base address at
 * which the object is mapped otherwise.
 */
struct dl_phdr_info {
    ElfW(Addr)      dlpi_addr;  /* Base address of object */
    const char      *dlpi_name; /* Null-terminated obj name */
    const ElfW(Phdr)    *dlpi_phdr; /* Ptr to ELF program hdr arr */
    ElfW(Half)      dlpi_phnum; /* # of items in dlpi_phdr[] */

    /*
     * Note: Following members were introduced after the first version
     * of this structure was available.  The dl_iterate_phdr() callback
     * function is passed a 'size' argument giving the size of the info
     * structure, and must compare that size to the offset of these fields
     * before accessing them to ensure that they are present.
     */

    /* Incremented when a new object is mapped into the process */
    u_longlong_t        dlpi_adds;
    /* Incremented when an object is unmapped from the process */
    u_longlong_t        dlpi_subs;
};

extern  int dl_iterate_phdr(int (*)(struct dl_phdr_info *, size_t, void *),
        void *);

#endif  /* _ASM */
#endif /* _KERNEL */


#ifdef __cplusplus
}
#endif

#endif  /* _LINK_H */