Subversion Repositories or1k

/* vi: set sw=8 ts=8: */

/*

 * ldso/ldso/sh64/elfinterp.c

 *

 * SuperH (sh64) ELF shared library loader suppport

 *

 * Copyright (C) 2003  Paul Mundt <lethal@linux-sh.org>

 *

 * 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. The name of the above contributors may not be

 *    used to endorse or promote products derived from this software

 *    without specific prior written permission.

 *

 * THIS SOFTWARE IS PROVIDED BY THE CONTRIBUTORS ``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 CONTRIBUTORS 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.

 */

#ifdef __SUPPORT_LD_DEBUG__

static const char *_dl_reltypes_tab[] = {

        /* SHcompact relocs */

          [0] =  "R_SH_NONE",            "R_SH_DIR32",

                "R_SH_REL32",           "R_SH_DIR8WPN",

          [4] = "R_SH_IND12W",          "R_SH_DIR8WPL",

                "R_SH_DIR8WPZ",         "R_SH_DIR8BP",

          [8] = "R_SH_DIR8W",           "R_SH_DIR8L",

         [25] = "R_SH_SWITCH16",        "R_SH_SWITCH32",

                "R_SH_USES",            "R_SH_COUNT",

         [29] = "R_SH_ALIGN",           "R_SH_CODE",

                "R_SH_DATA",            "R_SH_LABEL",

         [33] = "R_SH_SWITCH8",         "R_SH_GNU_VTINHERIT",

                "R_SH_GNU_VTENTRY",

        [160] = "R_SH_GOT32",           "R_SH_PLT32",

                "R_SH_COPY",            "R_SH_GLOB_DAT",

        [164] = "R_SH_JMP_SLOT",        "R_SH_RELATIVE",

                "R_SH_GOTOFF",          "R_SH_GOTPC",

        /* SHmedia relocs */

         [45] = "R_SH_DIR5U",           "R_SH_DIR6U",

                "R_SH_DIR6S",           "R_SH_DIR10S",

         [49] = "R_SH_DIR10SW",         "R_SH_DIR10SL",

                "R_SH_DIR10SQ",

        [169] = "R_SH_GOT_LOW16",       "R_SH_GOT_MEDLOW16",

                "R_SH_GOT_MEDHI16",     "R_SH_GOT_HI16",

        [173] = "R_SH_GOTPLT_LOW16",    "R_SH_GOTPLT_MEDLOW16",

                "R_SH_GOTPLT_MEDHI16",  "R_SH_GOTPLT_HI16",

        [177] = "R_SH_PLT_LOW16",       "R_SH_PLT_MEDLOW16",

                "R_SH_PLT_MEDHI16",     "R_SH_PLT_HI16",

        [181] = "R_SH_GOTOFF_LOW16",    "R_SH_GOTOFF_MEDLOW16",

                "R_SH_GOTOFF_MEDHI16",  "R_SH_GOTOFF_HI16",

        [185] = "R_SH_GOTPC_LOW16",     "R_SH_GOTPC_MEDLOW16",

                "R_SH_GOTPC_MEDHI16",   "R_SH_GOTPC_HI16",

        [189] = "R_SH_GOT10BY4",        "R_SH_GOTPLT10BY4",

                "R_SH_GOT10BY8",        "R_SH_GOTPLT10BY8",

        [193] = "R_SH_COPY64",          "R_SH_GLOB_DAT64",

                "R_SH_JMP_SLOT64",      "R_SH_RELATIVE64",

        [197] = "R_SH_RELATIVE_LOW16",  "R_SH_RELATIVE_MEDLOW16",

                "R_SH_RELATIVE_MEDHI16","R_SH_RELATIVE_HI16",

        [242] = "R_SH_SHMEDIA_CODE",    "R_SH_PT_16",

                "R_SH_IMMS16",          "R_SH_IMMU16",

        [246] = "R_SH_IMM_LOW16",       "R_SH_IMM_LOW16_PCREL",

                "R_SH_IMM_MEDLOW16",    "R_SH_IMM_MEDLOW16_PCREL",

        [250] = "R_SH_IMM_MEDHI16",     "R_SH_IMM_MEDHI16_PCREL",

                "R_SH_IMM_HI16",        "R_SH_IMM_HI16_PCREL",

        [254] = "R_SH_64",              "R_SH_64_PCREL",

};

static const char *_dl_reltypes(int type)

{

        static char buf[22];

        const char *str;

        int tabsize;

        tabsize = sizeof(_dl_reltypes_tab)/sizeof(_dl_reltypes_tab[0]);

        str     = _dl_reltypes_tab[type];

        if (type >= tabsize || str == NULL)

                str =_dl_simple_ltoa(buf, (unsigned long)(type));

        return str;

}

static void debug_sym(Elf32_Sym *symtab, char *strtab, int symtab_index)

{

        if (!_dl_debug_symbols || !symtab_index)

                return;

        _dl_dprintf(_dl_debug_file,

                "\n%s\tvalue=%x\tsize=%x\tinfo=%x\tother=%x\tshndx=%x",

                strtab + symtab[symtab_index].st_name,

                symtab[symtab_index].st_value,

                symtab[symtab_index].st_size,

                symtab[symtab_index].st_info,

                symtab[symtab_index].st_other,

                symtab[symtab_index].st_shndx);

}

static void debug_reloc(Elf32_Sym *symtab, char *strtab, ELF_RELOC *rpnt)

{

        if (!_dl_debug_reloc)

                return;

        if (_dl_debug_symbols) {

                _dl_dprintf(_dl_debug_file, "\n\t");

        } else {

                int symtab_index;

                const char *sym;

                symtab_index = ELF32_R_SYM(rpnt->r_info);

                sym = symtab_index ? strtab + symtab[symtab_index].st_name

                                   : "sym=0x0";

                _dl_dprintf(_dl_debug_file, "\n%s\n\t", sym);

        }

        _dl_dprintf(_dl_debug_file, "%s\toffset=%x",

                    _dl_reltypes(ELF32_R_TYPE(rpnt->r_info)),

                    rpnt->r_offset);

#ifdef ELF_USES_RELOCA

        _dl_dprintf(_dl_debug_file, "\taddend=%x", rpnt->r_addend);

#endif

        _dl_dprintf(_dl_debug_file, "\n");

}

#endif /* __SUPPORT_LD_DEBUG__ */

/* Program to load an ELF binary on a linux system, and run it.

   References to symbols in sharable libraries can be resolved by either

   an ELF sharable library or a linux style of shared library. */

/* Disclaimer:  I have never seen any AT&T source code for SVr4, nor have

   I ever taken any courses on internals.  This program was developed using

   information available through the book "UNIX SYSTEM V RELEASE 4,

   Programmers guide: Ansi C and Programming Support Tools", which did

   a more than adequate job of explaining everything required to get this

   working. */

extern int _dl_linux_resolve(void);

unsigned long _dl_linux_resolver(struct elf_resolve *tpnt, int reloc_entry)

{

        int reloc_type;

        ELF_RELOC *this_reloc;

        char *strtab;

        Elf32_Sym *symtab;

        int symtab_index;

        char *rel_addr;

        char *new_addr;

        char **got_addr;

        unsigned long instr_addr;

        char *symname;

        rel_addr = (char *)(tpnt->dynamic_info[DT_JMPREL] + tpnt->loadaddr);

        this_reloc = (ELF_RELOC *)(intptr_t)(rel_addr + reloc_entry);

        reloc_type = ELF32_R_TYPE(this_reloc->r_info);

        symtab_index = ELF32_R_SYM(this_reloc->r_info);

        symtab = (Elf32_Sym *)(intptr_t)

                (tpnt->dynamic_info[DT_SYMTAB] + tpnt->loadaddr);

        strtab = (char *)(tpnt->dynamic_info[DT_STRTAB] + tpnt->loadaddr);

        symname = strtab + symtab[symtab_index].st_name;

        if (reloc_type != R_SH_JMP_SLOT) {

                _dl_dprintf(2, "%s: Incorrect relocation type in jump reloc\n",

                            _dl_progname);

                _dl_exit(1);

        }

        /* Address of jump instruction to fix up */

        instr_addr = ((unsigned long)this_reloc->r_offset +

                        (unsigned long)tpnt->loadaddr);

        got_addr = (char **)instr_addr;

        /* Get the address of the GOT entry */

        new_addr = _dl_find_hash(symname, tpnt->symbol_scope, tpnt, resolver);

        if (!new_addr) {

                new_addr = _dl_find_hash(symname, NULL, NULL, resolver);

                if (new_addr)

                        return (unsigned long)new_addr;

                _dl_dprintf(2, "%s: can't resolve symbol '%s'\n",

                            _dl_progname, symname);

                _dl_exit(1);

        }

#ifdef __SUPPORT_LD_DEBUG__

        if ((unsigned long)got_addr < 0x20000000) {

                if (_dl_debug_bindings) {

                        _dl_dprintf(_dl_debug_file, "\nresolve function: %s",

                                    symname);

                        if (_dl_debug_detail)

                                _dl_dprintf(_dl_debug_file,

                                            "\n\tpatched %x ==> %x @ %x\n",

                                            *got_addr, new_addr, got_addr);

                }

        }

        if (!_dl_debug_nofixups)

                *got_addr = new_addr;

#else

        *got_addr = new_addr;

#endif

        return (unsigned long)new_addr;

}

static int _dl_parse(struct elf_resolve *tpnt, struct dyn_elf *scope,

                     unsigned long rel_addr, unsigned long rel_size,

                     int (*reloc_fnc)(struct elf_resolve *tpnt,

                                      struct dyn_elf *scope,

                                      ELF_RELOC *rpnt, Elf32_Sym *symtab,

                                      char *strtab))

{

        unsigned int i;

        char *strtab;

        Elf32_Sym *symtab;

        ELF_RELOC *rpnt;

        int symtab_index;

        /* Now parse the relocation information */

        rpnt = (ELF_RELOC *)(intptr_t)(rel_addr + tpnt->loadaddr);

        rel_size = rel_size / sizeof(ELF_RELOC);

        symtab = (Elf32_Sym *)(intptr_t)

                (tpnt->dynamic_info[DT_SYMTAB] + tpnt->loadaddr);

        strtab = (char *)(tpnt->dynamic_info[DT_STRTAB] + tpnt->loadaddr);

        for (i = 0; i < rel_size; i++, rpnt++) {

                int res;

                symtab_index = ELF32_R_SYM(rpnt->r_info);

                /* When the dynamic linker bootstrapped itself, it resolved

                   some symbols. Make sure we do not do them again */

                if (!symtab_index && tpnt->libtype == program_interpreter)

                        continue;

                if (symtab_index && tpnt->libtype == program_interpreter &&

                    _dl_symbol(strtab + symtab[symtab_index].st_name))

                        continue;

#ifdef __SUPPORT_LD_DEBUG__

                debug_sym(symtab,strtab,symtab_index);

                debug_reloc(symtab,strtab,rpnt);

#endif

                res = reloc_fnc (tpnt, scope, rpnt, symtab, strtab);

                if (res == 0)

                        continue;

                _dl_dprintf(2, "\n%s: ",_dl_progname);

                if (symtab_index)

                        _dl_dprintf(2, "symbol '%s': ",

                                strtab + symtab[symtab_index].st_name);

                if (res < 0) {

                        int reloc_type = ELF32_R_TYPE(rpnt->r_info);

                        _dl_dprintf(2, "can't handle reloc type "

#ifdef __SUPPORT_LD_DEBUG__

                                        "%s\n", _dl_reltypes(reloc_type)

#else

                                        "%x\n", reloc_type

#endif                  

                        );

                        _dl_exit(-res);

                } else if (res > 0) {

                        _dl_dprintf(2, "can't resolve symbol\n");

                        return res;

                }

        }

        return 0;

}

static int _dl_do_reloc(struct elf_resolve *tpnt,struct dyn_elf *scope,

                        ELF_RELOC *rpnt, Elf32_Sym *symtab, char *strtab)

{

        int reloc_type;

        int symtab_index, lsb;

        char *symname;

        unsigned long *reloc_addr;

        unsigned long symbol_addr;

#ifdef __SUPPORT_LD_DEBUG__

        unsigned long old_val;

#endif

        reloc_type   = ELF32_R_TYPE(rpnt->r_info);

        symtab_index = ELF32_R_SYM(rpnt->r_info);

        symbol_addr  = 0;

        lsb          = symtab[symtab_index].st_other & 4;

        symname      = strtab + symtab[symtab_index].st_name;

        reloc_addr   = (unsigned long *)(intptr_t)

                (tpnt->loadaddr + (unsigned long)rpnt->r_offset);

        if (symtab_index) {

                int stb;

                symbol_addr = (unsigned long)_dl_find_hash(symname, scope,

                                (reloc_type == R_SH_JMP_SLOT ? tpnt : NULL),

                                 symbolrel);

                /*

                 * We want to allow undefined references to weak symbols - this

                 * might have been intentional. We should not be linking local

                 * symbols here, so all bases should be covered.

                 */

                stb = ELF32_ST_BIND(symtab[symtab_index].st_info);

                if (stb == STB_GLOBAL && !symbol_addr) {

#ifdef __SUPPORT_LD_DEBUG__

                        _dl_dprintf(2, "\tglobal symbol '%s' "

                                    "already defined in '%s'\n",

                                    symname, tpnt->libname);

#endif

                        return 0;

                }

        }

#ifdef __SUPPORT_LD_DEBUG__

        old_val = *reloc_addr;

#endif

        switch (reloc_type) {

        case R_SH_NONE:

                break;

        case R_SH_COPY:

                /* handled later on */

                break;

        case R_SH_DIR32:

        case R_SH_GLOB_DAT:

        case R_SH_JMP_SLOT:

                *reloc_addr = (symbol_addr + rpnt->r_addend) | lsb;

                break;

        case R_SH_REL32:

                *reloc_addr = symbol_addr + rpnt->r_addend -

                        (unsigned long)reloc_addr;

                break;

        case R_SH_RELATIVE:

                *reloc_addr = (unsigned long)tpnt->loadaddr + rpnt->r_addend;

                break;

        case R_SH_RELATIVE_LOW16:

        case R_SH_RELATIVE_MEDLOW16:

            {

                unsigned long word, value;

                word = (unsigned long)reloc_addr & ~0x3fffc00;

                value = (unsigned long)tpnt->loadaddr + rpnt->r_addend;

                if (reloc_type == R_SH_RELATIVE_MEDLOW16)

                        value >>= 16;

                word |= (value & 0xffff) << 10;

                *reloc_addr = word;

                break;

            }

        case R_SH_IMM_LOW16:

        case R_SH_IMM_MEDLOW16:

            {

                unsigned long word, value;

                word = (unsigned long)reloc_addr & ~0x3fffc00;

                value = (symbol_addr + rpnt->r_addend) | lsb;

                if (reloc_type == R_SH_IMM_MEDLOW16)

                        value >>= 16;

                word |= (value & 0xffff) << 10;

                *reloc_addr = word;

                break;

            }

        case R_SH_IMM_LOW16_PCREL:

        case R_SH_IMM_MEDLOW16_PCREL:

            {

                unsigned long word, value;

                word = (unsigned long)reloc_addr & ~0x3fffc00;

                value = symbol_addr + rpnt->r_addend -

                        (unsigned long)reloc_addr;

                if (reloc_type == R_SH_IMM_MEDLOW16_PCREL)

                        value >>= 16;

                word |= (value & 0xffff) << 10;

                *reloc_addr = word;

                break;

            }

        default:

                return -1; /*call _dl_exit(1) */

        }

#ifdef __SUPPORT_LD_DEBUG__

        if (_dl_debug_reloc && _dl_debug_detail)

                _dl_dprintf(_dl_debug_file, "\tpatched: %x ==> %x @ %x",

                            old_val, *reloc_addr, reloc_addr);

#endif

        return 0;

}

static int _dl_do_lazy_reloc(struct elf_resolve *tpnt, struct dyn_elf *scope,

                             ELF_RELOC *rpnt, Elf32_Sym *symtab, char *strtab)

{

        int reloc_type, symtab_index, lsb;

        unsigned long *reloc_addr;

#ifdef __SUPPORT_LD_DEBUG__

        unsigned long old_val;

#endif

        reloc_type   = ELF32_R_TYPE(rpnt->r_info);

        symtab_index = ELF32_R_SYM(rpnt->r_info);

        lsb          = symtab[symtab_index].st_other & 4;

        reloc_addr   = (unsigned long *)(intptr_t)

                (tpnt->loadaddr + (unsigned long)rpnt->r_offset);

#ifdef __SUPPORT_LD_DEBUG__

        old_val = *reloc_addr;

#endif

        switch (reloc_type) {

        case R_SH_NONE:

                break;

        case R_SH_JMP_SLOT:

                *reloc_addr += (unsigned long)tpnt->loadaddr | lsb;

                break;

        default:

                return -1; /*call _dl_exit(1) */

        }

#ifdef __SUPPORT_LD_DEBUG__

        if (_dl_debug_reloc && _dl_debug_detail)

                _dl_dprintf(_dl_debug_file, "\tpatched: %x ==> %x @ %x",

                            old_val, *reloc_addr, reloc_addr);

#endif

        return 0;

}

/* This is done as a separate step, because there are cases where

   information is first copied and later initialized.  This results in

   the wrong information being copied.  Someone at Sun was complaining about

   a bug in the handling of _COPY by SVr4, and this may in fact be what he

   was talking about.  Sigh. */

/* No, there are cases where the SVr4 linker fails to emit COPY relocs

   at all */

static int _dl_do_copy(struct elf_resolve *tpnt, struct dyn_elf *scope,

                       ELF_RELOC *rpnt, Elf32_Sym *symtab, char *strtab)

{

        int reloc_type;

        int symtab_index;

        unsigned long *reloc_addr;

        unsigned long symbol_addr;

        char *symname;

        int goof = 0;

        reloc_addr = (unsigned long *)(intptr_t)

                (tpnt->loadaddr + (unsigned long)rpnt->r_offset);

        reloc_type = ELF32_R_TYPE(rpnt->r_info);

        if (reloc_type != R_SH_COPY)

                return 0;

        symtab_index = ELF32_R_SYM(rpnt->r_info);

        symbol_addr  = 0;

        symname      = strtab + symtab[symtab_index].st_name;

        if (symtab_index) {

                symbol_addr = (unsigned long)

                        _dl_find_hash(symname, scope, NULL, copyrel);

                if (!symbol_addr)

                        goof++;

        }

        if (!goof) {

#ifdef __SUPPORT_LD_DEBUG__

                if (_dl_debug_move)

                        _dl_dprintf(_dl_debug_file,

                                    "\n%s move %x bytes from %x to %x",

                                    symname, symtab[symtab_index].st_size,

                                    symbol_addr, symtab[symtab_index].st_value);

#endif

                _dl_memcpy((char *)symtab[symtab_index].st_value,

                           (char *)symbol_addr, symtab[symtab_index].st_size);

        }

        return goof;

}

void _dl_parse_lazy_relocation_information(struct elf_resolve *tpnt,

                unsigned long rel_addr, unsigned long rel_size, int type)

{

        _dl_parse(tpnt, NULL, rel_addr, rel_size, _dl_do_lazy_reloc);

}

int _dl_parse_relocation_information(struct elf_resolve *tpnt,

                unsigned long rel_addr, unsigned long rel_size, int type)

{

        return _dl_parse(tpnt, tpnt->symbol_scope, rel_addr,

                         rel_size, _dl_do_reloc);

}

int _dl_parse_copy_information(struct dyn_elf *xpnt, unsigned long rel_addr,

    unsigned long rel_size, int type)

{

        return _dl_parse(xpnt->dyn, xpnt->next, rel_addr,

                         rel_size, _dl_do_copy);

}