diff options
Diffstat (limited to 'libexec/rtld-elf/sparc64/reloc.c')
| -rw-r--r-- | libexec/rtld-elf/sparc64/reloc.c | 693 |
1 files changed, 693 insertions, 0 deletions
diff --git a/libexec/rtld-elf/sparc64/reloc.c b/libexec/rtld-elf/sparc64/reloc.c new file mode 100644 index 0000000..1a897c3 --- /dev/null +++ b/libexec/rtld-elf/sparc64/reloc.c @@ -0,0 +1,693 @@ +/* $NetBSD: mdreloc.c,v 1.5 2001/04/25 12:24:51 kleink Exp $ */ + +/*- + * Copyright (c) 2000 Eduardo Horvath. + * Copyright (c) 1999 The NetBSD Foundation, Inc. + * All rights reserved. + * + * This code is derived from software contributed to The NetBSD Foundation + * by Paul Kranenburg. + * + * 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. + * 3. All advertising materials mentioning features or use of this software + * must display the following acknowledgement: + * This product includes software developed by the NetBSD + * Foundation, Inc. and its contributors. + * 4. Neither the name of The NetBSD Foundation nor the names of its + * contributors may be used to endorse or promote products derived + * from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND 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 FOUNDATION OR 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. + * + * $FreeBSD$ + */ + +#include <errno.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <unistd.h> +#include <sys/stat.h> + +#include "debug.h" +#include "rtld.h" + +/* + * The following table holds for each relocation type: + * - the width in bits of the memory location the relocation + * applies to (not currently used) + * - the number of bits the relocation value must be shifted to the + * right (i.e. discard least significant bits) to fit into + * the appropriate field in the instruction word. + * - flags indicating whether + * * the relocation involves a symbol + * * the relocation is relative to the current position + * * the relocation is for a GOT entry + * * the relocation is relative to the load address + * + */ +#define _RF_S 0x80000000 /* Resolve symbol */ +#define _RF_A 0x40000000 /* Use addend */ +#define _RF_P 0x20000000 /* Location relative */ +#define _RF_G 0x10000000 /* GOT offset */ +#define _RF_B 0x08000000 /* Load address relative */ +#define _RF_U 0x04000000 /* Unaligned */ +#define _RF_SZ(s) (((s) & 0xff) << 8) /* memory target size */ +#define _RF_RS(s) ( (s) & 0xff) /* right shift */ +static int reloc_target_flags[] = { + 0, /* NONE */ + _RF_S|_RF_A| _RF_SZ(8) | _RF_RS(0), /* RELOC_8 */ + _RF_S|_RF_A| _RF_SZ(16) | _RF_RS(0), /* RELOC_16 */ + _RF_S|_RF_A| _RF_SZ(32) | _RF_RS(0), /* RELOC_32 */ + _RF_S|_RF_A|_RF_P| _RF_SZ(8) | _RF_RS(0), /* DISP_8 */ + _RF_S|_RF_A|_RF_P| _RF_SZ(16) | _RF_RS(0), /* DISP_16 */ + _RF_S|_RF_A|_RF_P| _RF_SZ(32) | _RF_RS(0), /* DISP_32 */ + _RF_S|_RF_A|_RF_P| _RF_SZ(32) | _RF_RS(2), /* WDISP_30 */ + _RF_S|_RF_A|_RF_P| _RF_SZ(32) | _RF_RS(2), /* WDISP_22 */ + _RF_S|_RF_A| _RF_SZ(32) | _RF_RS(10), /* HI22 */ + _RF_S|_RF_A| _RF_SZ(32) | _RF_RS(0), /* 22 */ + _RF_S|_RF_A| _RF_SZ(32) | _RF_RS(0), /* 13 */ + _RF_S|_RF_A| _RF_SZ(32) | _RF_RS(0), /* LO10 */ + _RF_G| _RF_SZ(32) | _RF_RS(0), /* GOT10 */ + _RF_G| _RF_SZ(32) | _RF_RS(0), /* GOT13 */ + _RF_G| _RF_SZ(32) | _RF_RS(10), /* GOT22 */ + _RF_S|_RF_A|_RF_P| _RF_SZ(32) | _RF_RS(0), /* PC10 */ + _RF_S|_RF_A|_RF_P| _RF_SZ(32) | _RF_RS(10), /* PC22 */ + _RF_A|_RF_P| _RF_SZ(32) | _RF_RS(2), /* WPLT30 */ + _RF_SZ(32) | _RF_RS(0), /* COPY */ + _RF_S|_RF_A| _RF_SZ(64) | _RF_RS(0), /* GLOB_DAT */ + _RF_SZ(32) | _RF_RS(0), /* JMP_SLOT */ + _RF_A| _RF_B| _RF_SZ(64) | _RF_RS(0), /* RELATIVE */ + _RF_S|_RF_A| _RF_U| _RF_SZ(32) | _RF_RS(0), /* UA_32 */ + + _RF_A| _RF_SZ(32) | _RF_RS(0), /* PLT32 */ + _RF_A| _RF_SZ(32) | _RF_RS(10), /* HIPLT22 */ + _RF_A| _RF_SZ(32) | _RF_RS(0), /* LOPLT10 */ + _RF_A|_RF_P| _RF_SZ(32) | _RF_RS(0), /* PCPLT32 */ + _RF_A|_RF_P| _RF_SZ(32) | _RF_RS(10), /* PCPLT22 */ + _RF_A|_RF_P| _RF_SZ(32) | _RF_RS(0), /* PCPLT10 */ + _RF_S|_RF_A| _RF_SZ(32) | _RF_RS(0), /* 10 */ + _RF_S|_RF_A| _RF_SZ(32) | _RF_RS(0), /* 11 */ + _RF_S|_RF_A| _RF_SZ(64) | _RF_RS(0), /* 64 */ + _RF_S|_RF_A|/*extra*/ _RF_SZ(32) | _RF_RS(0), /* OLO10 */ + _RF_S|_RF_A| _RF_SZ(32) | _RF_RS(42), /* HH22 */ + _RF_S|_RF_A| _RF_SZ(32) | _RF_RS(32), /* HM10 */ + _RF_S|_RF_A| _RF_SZ(32) | _RF_RS(10), /* LM22 */ + _RF_S|_RF_A|_RF_P| _RF_SZ(32) | _RF_RS(42), /* PC_HH22 */ + _RF_S|_RF_A|_RF_P| _RF_SZ(32) | _RF_RS(32), /* PC_HM10 */ + _RF_S|_RF_A|_RF_P| _RF_SZ(32) | _RF_RS(10), /* PC_LM22 */ + _RF_S|_RF_A|_RF_P| _RF_SZ(32) | _RF_RS(2), /* WDISP16 */ + _RF_S|_RF_A|_RF_P| _RF_SZ(32) | _RF_RS(2), /* WDISP19 */ + _RF_S|_RF_A| _RF_SZ(32) | _RF_RS(0), /* GLOB_JMP */ + _RF_S|_RF_A| _RF_SZ(32) | _RF_RS(0), /* 7 */ + _RF_S|_RF_A| _RF_SZ(32) | _RF_RS(0), /* 5 */ + _RF_S|_RF_A| _RF_SZ(32) | _RF_RS(0), /* 6 */ + _RF_S|_RF_A|_RF_P| _RF_SZ(64) | _RF_RS(0), /* DISP64 */ + _RF_A| _RF_SZ(64) | _RF_RS(0), /* PLT64 */ + _RF_S|_RF_A| _RF_SZ(32) | _RF_RS(10), /* HIX22 */ + _RF_S|_RF_A| _RF_SZ(32) | _RF_RS(0), /* LOX10 */ + _RF_S|_RF_A| _RF_SZ(32) | _RF_RS(22), /* H44 */ + _RF_S|_RF_A| _RF_SZ(32) | _RF_RS(12), /* M44 */ + _RF_S|_RF_A| _RF_SZ(32) | _RF_RS(0), /* L44 */ + _RF_S|_RF_A| _RF_SZ(64) | _RF_RS(0), /* REGISTER */ + _RF_S|_RF_A| _RF_U| _RF_SZ(64) | _RF_RS(0), /* UA64 */ + _RF_S|_RF_A| _RF_U| _RF_SZ(16) | _RF_RS(0), /* UA16 */ +}; + +#if 0 +static const char *reloc_names[] = { + "NONE", "RELOC_8", "RELOC_16", "RELOC_32", "DISP_8", + "DISP_16", "DISP_32", "WDISP_30", "WDISP_22", "HI22", + "22", "13", "LO10", "GOT10", "GOT13", + "GOT22", "PC10", "PC22", "WPLT30", "COPY", + "GLOB_DAT", "JMP_SLOT", "RELATIVE", "UA_32", "PLT32", + "HIPLT22", "LOPLT10", "LOPLT10", "PCPLT22", "PCPLT32", + "10", "11", "64", "OLO10", "HH22", + "HM10", "LM22", "PC_HH22", "PC_HM10", "PC_LM22", + "WDISP16", "WDISP19", "GLOB_JMP", "7", "5", "6", + "DISP64", "PLT64", "HIX22", "LOX10", "H44", "M44", + "L44", "REGISTER", "UA64", "UA16" +}; +#endif + +#define RELOC_RESOLVE_SYMBOL(t) ((reloc_target_flags[t] & _RF_S) != 0) +#define RELOC_PC_RELATIVE(t) ((reloc_target_flags[t] & _RF_P) != 0) +#define RELOC_BASE_RELATIVE(t) ((reloc_target_flags[t] & _RF_B) != 0) +#define RELOC_UNALIGNED(t) ((reloc_target_flags[t] & _RF_U) != 0) +#define RELOC_USE_ADDEND(t) ((reloc_target_flags[t] & _RF_A) != 0) +#define RELOC_TARGET_SIZE(t) ((reloc_target_flags[t] >> 8) & 0xff) +#define RELOC_VALUE_RIGHTSHIFT(t) (reloc_target_flags[t] & 0xff) + +static long reloc_target_bitmask[] = { +#define _BM(x) (~(-(1ULL << (x)))) + 0, /* NONE */ + _BM(8), _BM(16), _BM(32), /* RELOC_8, _16, _32 */ + _BM(8), _BM(16), _BM(32), /* DISP8, DISP16, DISP32 */ + _BM(30), _BM(22), /* WDISP30, WDISP22 */ + _BM(22), _BM(22), /* HI22, _22 */ + _BM(13), _BM(10), /* RELOC_13, _LO10 */ + _BM(10), _BM(13), _BM(22), /* GOT10, GOT13, GOT22 */ + _BM(10), _BM(22), /* _PC10, _PC22 */ + _BM(30), 0, /* _WPLT30, _COPY */ + _BM(32), _BM(32), _BM(32), /* _GLOB_DAT, JMP_SLOT, _RELATIVE */ + _BM(32), _BM(32), /* _UA32, PLT32 */ + _BM(22), _BM(10), /* _HIPLT22, LOPLT10 */ + _BM(32), _BM(22), _BM(10), /* _PCPLT32, _PCPLT22, _PCPLT10 */ + _BM(10), _BM(11), -1, /* _10, _11, _64 */ + _BM(10), _BM(22), /* _OLO10, _HH22 */ + _BM(10), _BM(22), /* _HM10, _LM22 */ + _BM(22), _BM(10), _BM(22), /* _PC_HH22, _PC_HM10, _PC_LM22 */ + _BM(16), _BM(19), /* _WDISP16, _WDISP19 */ + -1, /* GLOB_JMP */ + _BM(7), _BM(5), _BM(6) /* _7, _5, _6 */ + -1, -1, /* DISP64, PLT64 */ + _BM(22), _BM(13), /* HIX22, LOX10 */ + _BM(22), _BM(10), _BM(13), /* H44, M44, L44 */ + -1, -1, _BM(16), /* REGISTER, UA64, UA16 */ +#undef _BM +}; +#define RELOC_VALUE_BITMASK(t) (reloc_target_bitmask[t]) + +#undef flush +#define flush(va, offs) \ + __asm __volatile("flush %0 + %1" : : "r" (va), "I" (offs)); + +static int reloc_nonplt_object(Obj_Entry *obj, const Elf_Rela *rela, + SymCache *cache); +static void install_plt(Elf_Half *pltgot, Elf_Addr proc); + +extern char _rtld_bind_start_0[]; +extern char _rtld_bind_start_1[]; + +int +do_copy_relocations(Obj_Entry *dstobj) +{ + const Elf_Rela *relalim; + const Elf_Rela *rela; + const Elf_Sym *dstsym; + const Elf_Sym *srcsym; + void *dstaddr; + const void *srcaddr; + Obj_Entry *srcobj; + unsigned long hash; + const char *name; + size_t size; + + assert(dstobj->mainprog); /* COPY relocations are invalid elsewhere */ + + relalim = (const Elf_Rela *)((caddr_t)dstobj->rela + dstobj->relasize); + for (rela = dstobj->rela; rela < relalim; rela++) { + if (ELF_R_TYPE(rela->r_info) == R_SPARC_COPY) { + dstaddr = (void *)(dstobj->relocbase + rela->r_offset); + dstsym = dstobj->symtab + ELF_R_SYM(rela->r_info); + name = dstobj->strtab + dstsym->st_name; + hash = elf_hash(name); + size = dstsym->st_size; + + for (srcobj = dstobj->next; srcobj != NULL; + srcobj = srcobj->next) + if ((srcsym = symlook_obj(name, hash, srcobj, + false)) != NULL) + break; + + if (srcobj == NULL) { + _rtld_error("Undefined symbol \"%s\"" + "referenced from COPY relocation" + "in %s", name, dstobj->path); + return (-1); + } + + srcaddr = (const void *)(srcobj->relocbase + + srcsym->st_value); + memcpy(dstaddr, srcaddr, size); + } + } + + return (0); +} + +int +reloc_non_plt(Obj_Entry *obj, Obj_Entry *obj_rtld) +{ + const Elf_Rela *relalim; + const Elf_Rela *rela; + SymCache *cache; + + cache = (SymCache *)alloca(obj->nchains * sizeof(SymCache)); + if (cache != NULL) + memset(cache, 0, obj->nchains * sizeof(SymCache)); + + relalim = (const Elf_Rela *)((caddr_t)obj->rela + obj->relasize); + for (rela = obj->rela; rela < relalim; rela++) { + if (reloc_nonplt_object(obj, rela, cache) < 0) + return (-1); + } + + return (0); +} + +static int +reloc_nonplt_object(Obj_Entry *obj, const Elf_Rela *rela, SymCache *cache) +{ + const Obj_Entry *defobj; + const Elf_Sym *def; + Elf_Addr *where; + Elf_Half *where32; + Elf_Word type; + Elf_Addr value; + Elf_Addr mask; + + where = (Elf_Addr *)(obj->relocbase + rela->r_offset); + where32 = (Elf_Half *)where; + defobj = NULL; + def = NULL; + + type = ELF_R_TYPE(rela->r_info); + if (type == R_SPARC_NONE) + return (0); + + /* We do JMP_SLOTs below */ + if (type == R_SPARC_JMP_SLOT) + return (0); + + /* COPY relocs are also handled elsewhere */ + if (type == R_SPARC_COPY) + return (0); + + /* + * Note: R_SPARC_UA16 must be numerically largest relocation type. + */ + if (type > R_SPARC_UA16) + return (-1); + + value = rela->r_addend; + + /* + * Handle relative relocs here, because we might not + * be able to access globals yet. + */ + if (type == R_SPARC_RELATIVE) { + /* XXXX -- apparently we ignore the preexisting value */ + *where = (Elf_Addr)(obj->relocbase + value); + return (0); + } + + /* + * If we get here while relocating rtld itself, we will crash because + * a non-local variable is accessed. + */ + if (RELOC_RESOLVE_SYMBOL(type)) { + + /* Find the symbol */ + def = find_symdef(ELF_R_SYM(rela->r_info), obj, &defobj, + false, cache); + if (def == NULL) + return (-1); + + /* Add in the symbol's absolute address */ + value += (Elf_Addr)(defobj->relocbase + def->st_value); + } + + if (RELOC_PC_RELATIVE(type)) + value -= (Elf_Addr)where; + + if (RELOC_BASE_RELATIVE(type)) { + /* + * Note that even though sparcs use `Elf_rela' exclusively + * we still need the implicit memory addend in relocations + * referring to GOT entries. Undoubtedly, someone f*cked + * this up in the distant past, and now we're stuck with + * it in the name of compatibility for all eternity.. + * + * In any case, the implicit and explicit should be mutually + * exclusive. We provide a check for that here. + */ + /* XXXX -- apparently we ignore the preexisting value */ + value += (Elf_Addr)(obj->relocbase); + } + + mask = RELOC_VALUE_BITMASK(type); + value >>= RELOC_VALUE_RIGHTSHIFT(type); + value &= mask; + + if (RELOC_UNALIGNED(type)) { + /* Handle unaligned relocations. */ + Elf_Addr tmp; + char *ptr; + int size; + int i; + + size = RELOC_TARGET_SIZE(type) / 8; + ptr = (char *)where; + tmp = 0; + + /* Read it in one byte at a time. */ + for (i = 0; i < size; i++) + tmp = (tmp << 8) | ptr[i]; + + tmp &= ~mask; + tmp |= value; + + /* Write it back out. */ + for (i = 0; i < size; i++) + ptr[i] = ((tmp >> (8 * i)) & 0xff); + } else if (RELOC_TARGET_SIZE(type) > 32) { + *where &= ~mask; + *where |= value; + } else { + *where32 &= ~mask; + *where32 |= value; + } + + return (0); +} + +int +reloc_plt(Obj_Entry *obj) +{ +#if 0 + const Obj_Entry *defobj; + const Elf_Rela *relalim; + const Elf_Rela *rela; + const Elf_Sym *def; + Elf_Addr *where; + Elf_Addr value; + + relalim = (const Elf_Rela *)((char *)obj->pltrela + obj->pltrelasize); + for (rela = obj->pltrela; rela < relalim; rela++) { + if (rela->r_addend == 0) + continue; + assert(ELF_R_TYPE(rela->r_info) == R_SPARC_JMP_SLOT); + where = (Elf_Addr *)(obj->relocbase + rela->r_offset); + def = find_symdef(ELF_R_SYM(rela->r_info), obj, &defobj, + true, NULL); + value = (Elf_Addr)(defobj->relocbase + def->st_value); + *where = value; + } +#endif + return (0); +} + +/* + * Instruction templates: + */ +#define BAA 0x10400000 /* ba,a %xcc, 0 */ +#define SETHI 0x03000000 /* sethi %hi(0), %g1 */ +#define JMP 0x81c06000 /* jmpl %g1+%lo(0), %g0 */ +#define NOP 0x01000000 /* sethi %hi(0), %g0 */ +#define OR 0x82806000 /* or %g1, 0, %g1 */ +#define XOR 0x82c06000 /* xor %g1, 0, %g1 */ +#define MOV71 0x8283a000 /* or %o7, 0, %g1 */ +#define MOV17 0x9c806000 /* or %g1, 0, %o7 */ +#define CALL 0x40000000 /* call 0 */ +#define SLLX 0x8b407000 /* sllx %g1, 0, %g1 */ +#define SETHIG5 0x0b000000 /* sethi %hi(0), %g5 */ +#define ORG5 0x82804005 /* or %g1, %g5, %g1 */ + + +/* %hi(v) with variable shift */ +#define HIVAL(v, s) (((v) >> (s)) & 0x003fffff) +#define LOVAL(v) ((v) & 0x000003ff) + +int +reloc_jmpslots(Obj_Entry *obj) +{ + const Obj_Entry *defobj; + const Elf_Rela *relalim; + const Elf_Rela *rela; + const Elf_Sym *def; + Elf_Addr *where; + Elf_Addr target; + + relalim = (const Elf_Rela *)((char *)obj->pltrela + obj->pltrelasize); + for (rela = obj->pltrela; rela < relalim; rela++) { + assert(ELF_R_TYPE(rela->r_info) == R_SPARC_JMP_SLOT); + where = (Elf_Addr *)(obj->relocbase + rela->r_offset); + def = find_symdef(ELF_R_SYM(rela->r_info), obj, &defobj, + true, NULL); + target = (Elf_Addr)(defobj->relocbase + def->st_value); + reloc_jmpslot(where, target, defobj); + } + obj->jmpslots_done = true; + return (0); +} + +Elf_Addr +reloc_jmpslot(Elf_Addr *wherep, Elf_Addr target, const Obj_Entry *obj) +{ + Elf_Addr offset; + Elf_Half *where; + + /* + * At the PLT entry pointed at by `where', we now construct + * a direct transfer to the now fully resolved function + * address. + * + * A PLT entry is supposed to start by looking like this: + * + * sethi %hi(. - .PLT0), %g1 + * ba,a %xcc, .PLT1 + * nop + * nop + * nop + * nop + * nop + * nop + * + * When we replace these entries we start from the second + * entry and do it in reverse order so the last thing we + * do is replace the branch. That allows us to change this + * atomically. + * + * We now need to find out how far we need to jump. We + * have a choice of several different relocation techniques + * which are increasingly expensive. + */ + + where = (Elf_Half *)wherep; + offset = ((Elf_Addr)where) - target; + if (offset <= (1L<<20) && offset >= -(1L<<20)) { + /* + * We're within 1MB -- we can use a direct branch insn. + * + * We can generate this pattern: + * + * sethi %hi(. - .PLT0), %g1 + * ba,a %xcc, addr + * nop + * nop + * nop + * nop + * nop + * nop + * + */ + where[1] = BAA | ((offset >> 2) &0x3fffff); + flush(where, 4); + } else if (target >= 0 && target < (1L<<32)) { + /* + * We're withing 32-bits of address zero. + * + * The resulting code in the jump slot is: + * + * sethi %hi(. - .PLT0), %g1 + * sethi %hi(addr), %g1 + * jmp %g1+%lo(addr) + * nop + * nop + * nop + * nop + * nop + * + */ + where[2] = JMP | LOVAL(target); + flush(where, 8); + where[1] = SETHI | HIVAL(target, 10); + flush(where, 4); + } else if (target <= 0 && target > -(1L<<32)) { + /* + * We're withing 32-bits of address -1. + * + * The resulting code in the jump slot is: + * + * sethi %hi(. - .PLT0), %g1 + * sethi %hix(addr), %g1 + * xor %g1, %lox(addr), %g1 + * jmp %g1 + * nop + * nop + * nop + * nop + * + */ + where[3] = JMP; + flush(where, 12); + where[2] = XOR | ((~target) & 0x00001fff); + flush(where, 8); + where[1] = SETHI | HIVAL(~target, 10); + flush(where, 4); + } else if (offset <= (1L<<32) && offset >= -((1L<<32) - 4)) { + /* + * We're withing 32-bits -- we can use a direct call insn + * + * The resulting code in the jump slot is: + * + * sethi %hi(. - .PLT0), %g1 + * mov %o7, %g1 + * call (.+offset) + * mov %g1, %o7 + * nop + * nop + * nop + * nop + * + */ + where[3] = MOV17; + flush(where, 12); + where[2] = CALL | ((offset >> 4) & 0x3fffffff); + flush(where, 8); + where[1] = MOV71; + flush(where, 4); + } else if (offset >= 0 && offset < (1L<<44)) { + /* + * We're withing 44 bits. We can generate this pattern: + * + * The resulting code in the jump slot is: + * + * sethi %hi(. - .PLT0), %g1 + * sethi %h44(addr), %g1 + * or %g1, %m44(addr), %g1 + * sllx %g1, 12, %g1 + * jmp %g1+%l44(addr) + * nop + * nop + * nop + * + */ + where[4] = JMP | LOVAL(offset); + flush(where, 16); + where[3] = SLLX | 12; + flush(where, 12); + where[2] = OR | (((offset) >> 12) & 0x00001fff); + flush(where, 8); + where[1] = SETHI | HIVAL(offset, 22); + flush(where, 4); + } else if (offset < 0 && offset > -(1L<<44)) { + /* + * We're withing 44 bits. We can generate this pattern: + * + * The resulting code in the jump slot is: + * + * sethi %hi(. - .PLT0), %g1 + * sethi %h44(-addr), %g1 + * xor %g1, %m44(-addr), %g1 + * sllx %g1, 12, %g1 + * jmp %g1+%l44(addr) + * nop + * nop + * nop + * + */ + where[4] = JMP | LOVAL(offset); + flush(where, 16); + where[3] = SLLX | 12; + flush(where, 12); + where[2] = XOR | (((~offset) >> 12) & 0x00001fff); + flush(where, 8); + where[1] = SETHI | HIVAL(~offset, 22); + flush(where, 4); + } else { + /* + * We need to load all 64-bits + * + * The resulting code in the jump slot is: + * + * sethi %hi(. - .PLT0), %g1 + * sethi %hh(addr), %g1 + * sethi %lm(addr), %g5 + * or %g1, %hm(addr), %g1 + * sllx %g1, 32, %g1 + * or %g1, %g5, %g1 + * jmp %g1+%lo(addr) + * nop + * + */ + where[6] = JMP | LOVAL(target); + flush(where, 24); + where[5] = ORG5; + flush(where, 20); + where[4] = SLLX | 12; + flush(where, 16); + where[3] = OR | LOVAL((target) >> 32); + flush(where, 12); + where[2] = SETHIG5 | HIVAL(target, 10); + flush(where, 8); + where[1] = SETHI | HIVAL(target, 42); + flush(where, 4); + } + + return (target); +} + +/* + * Install rtld function call into this PLT slot. + */ +#define SAVE 0x9de3bf50 +#define SETHI_l0 0x21000000 +#define SETHI_l1 0x23000000 +#define OR_l0_l0 0xa0142000 +#define SLLX_l0_32_l0 0xa12c3020 +#define OR_l0_l1_l0 0xa0140011 +#define JMPL_l0_o1 0x93c42000 +#define MOV_g1_o0 0x90100001 + +void +init_pltgot(Obj_Entry *obj) +{ + Elf_Half *entry; + + if (obj->pltgot != NULL) { + entry = (Elf_Half *)obj->pltgot; + install_plt(&entry[0], (Elf_Addr)_rtld_bind_start_0); + install_plt(&entry[8], (Elf_Addr)_rtld_bind_start_1); + obj->pltgot[8] = (Elf_Addr)obj; + } +} + +static void +install_plt(Elf_Half *pltgot, Elf_Addr proc) +{ + pltgot[0] = SAVE; + flush(pltgot, 0); + pltgot[1] = SETHI_l0 | HIVAL(proc, 42); + flush(pltgot, 4); + pltgot[2] = SETHI_l1 | HIVAL(proc, 10); + flush(pltgot, 8); + pltgot[3] = OR_l0_l0 | LOVAL((proc) >> 32); + flush(pltgot, 12); + pltgot[4] = SLLX_l0_32_l0; + flush(pltgot, 16); + pltgot[5] = OR_l0_l1_l0; + flush(pltgot, 20); + pltgot[6] = JMPL_l0_o1 | LOVAL(proc); + flush(pltgot, 24); + pltgot[7] = MOV_g1_o0; + flush(pltgot, 28); +} |
