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author | dfr <dfr@FreeBSD.org> | 1998-09-04 19:03:57 +0000 |
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committer | dfr <dfr@FreeBSD.org> | 1998-09-04 19:03:57 +0000 |
commit | b5ab30c0dc5fcbceebb8fe7939b9b22b365dbb81 (patch) | |
tree | b5d0a554c070d669d34d1dd16aedbdc80ac19468 /libexec/rtld-elf/alpha/reloc.c | |
parent | cc6d00dd2e04653dd42a1e017648ef5a6865205e (diff) | |
download | FreeBSD-src-b5ab30c0dc5fcbceebb8fe7939b9b22b365dbb81.zip FreeBSD-src-b5ab30c0dc5fcbceebb8fe7939b9b22b365dbb81.tar.gz |
Add alpha support.
Submitted by: John Birrell <jb@cimlogic.com.au> (with extra hacks by me)
Obtained from: Probably NetBSD
Diffstat (limited to 'libexec/rtld-elf/alpha/reloc.c')
-rw-r--r-- | libexec/rtld-elf/alpha/reloc.c | 309 |
1 files changed, 309 insertions, 0 deletions
diff --git a/libexec/rtld-elf/alpha/reloc.c b/libexec/rtld-elf/alpha/reloc.c new file mode 100644 index 0000000..e43b12a --- /dev/null +++ b/libexec/rtld-elf/alpha/reloc.c @@ -0,0 +1,309 @@ +/*- + * Copyright 1996-1998 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. + * + * $Id: rtld.c,v 1.3 1998/05/01 08:39:27 dfr Exp $ + */ + +/* + * Dynamic linker for ELF. + * + * John Polstra <jdp@polstra.com>. + */ + +#include <sys/param.h> +#include <sys/mman.h> + +#include <dlfcn.h> +#include <err.h> +#include <errno.h> +#include <fcntl.h> +#include <stdarg.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <unistd.h> + +#include "debug.h" +#include "rtld.h" + +/* + * Debugging support. + */ + +#define assert(cond) ((cond) ? (void) 0 :\ + (msg("oops: " __XSTRING(__LINE__) "\n"), abort())) +#define msg(s) (write(1, s, strlen(s))) +#define trace() msg("trace: " __XSTRING(__LINE__) "\n"); + +extern Elf_Dyn _DYNAMIC; + +/* Relocate a non-PLT object with addend. */ +static int +reloc_non_plt_obj(Obj_Entry *obj_rtld, const Obj_Entry *obj, + const Elf_Rela *rela) +{ + Elf_Addr *where = (Elf_Addr *) (obj->relocbase + rela->r_offset); + + switch (ELF_R_TYPE(rela->r_info)) { + + case R_ALPHA_REFQUAD: { + const Elf_Sym *def; + const Obj_Entry *defobj; + Elf_Addr tmp_value; + + def = find_symdef(ELF_R_SYM(rela->r_info), obj, + &defobj, false); + if (def == NULL) + return -1; + + tmp_value = (Elf_Addr) (defobj->relocbase + + def->st_value) + *where + rela->r_addend; + if (*where != tmp_value) + *where = tmp_value; + } + break; + + case R_ALPHA_GLOB_DAT: { + const Elf_Sym *def; + const Obj_Entry *defobj; + + def = find_symdef(ELF_R_SYM(rela->r_info), obj, + &defobj, false); + if (def == NULL) + return -1; + + if (*where != (Elf_Addr) (defobj->relocbase + + def->st_value)) + *where = (Elf_Addr) (defobj->relocbase + + def->st_value); + } + break; + + case R_ALPHA_RELATIVE: { + if (obj != obj_rtld || + (caddr_t)where < (caddr_t)_GLOBAL_OFFSET_TABLE_ || + (caddr_t)where >= (caddr_t)&_DYNAMIC) + *where += (Elf_Addr) obj->relocbase; + } + break; + + case R_ALPHA_COPY: { + /* + * These are deferred until all other relocations + * have been done. All we do here is make sure + * that the COPY relocation is not in a shared + * library. They are allowed only in executable + * files. + */ + if (!obj->mainprog) { + _rtld_error("%s: Unexpected R_COPY " + " relocation in shared library", + obj->path); + return -1; + } + } + break; + + default: + _rtld_error("%s: Unsupported relocation type %d" + " in non-PLT relocations\n", obj->path, + ELF_R_TYPE(rela->r_info)); + return -1; + } + return(0); +} + +/* Process the non-PLT relocations. */ +int +reloc_non_plt(Obj_Entry *obj, Obj_Entry *obj_rtld) +{ + const Elf_Rel *rellim; + const Elf_Rel *rel; + const Elf_Rela *relalim; + const Elf_Rela *rela; + + /* Perform relocations without addend if there are any: */ + rellim = (const Elf_Rel *) ((caddr_t) obj->rel + obj->relsize); + for (rel = obj->rel; obj->rel != NULL && rel < rellim; rel++) { + Elf_Rela locrela; + + locrela.r_info = rel->r_info; + locrela.r_offset = rel->r_offset; + locrela.r_addend = 0; + if (reloc_non_plt_obj(obj_rtld, obj, &locrela)) + return -1; + } + + /* Perform relocations with addend if there are any: */ + relalim = (const Elf_Rela *) ((caddr_t) obj->rela + obj->relasize); + for (rela = obj->rela; obj->rela != NULL && rela < relalim; rela++) { + if (reloc_non_plt_obj(obj_rtld, obj, rela)) + return -1; + } + return 0; +} + +/* Process the PLT relocations. */ +int +reloc_plt(Obj_Entry *obj, bool bind_now) +{ + const Elf_Rel *rellim; + const Elf_Rel *rel; + const Elf_Rela *relalim; + const Elf_Rela *rela; + + /* Process the PLT relocations without addend if there are any. */ + rellim = (const Elf_Rel *) ((caddr_t) obj->pltrel + obj->pltrelsize); + if (bind_now) { + /* Fully resolve procedure addresses now */ + for (rel = obj->pltrel; obj->pltrel != NULL && rel < rellim; + rel++) { + Elf_Addr *where = (Elf_Addr *) (obj->relocbase + rel->r_offset); + const Elf_Sym *def; + const Obj_Entry *defobj; + + assert(ELF_R_TYPE(rel->r_info) == R_ALPHA_JMP_SLOT); + + def = find_symdef(ELF_R_SYM(rel->r_info), obj, &defobj, true); + if (def == NULL) + return -1; + + *where = (Elf_Addr) (defobj->relocbase + def->st_value); + } + } else { /* Just relocate the GOT slots pointing into the PLT */ + for (rel = obj->pltrel; obj->pltrel != NULL && rel < rellim; + rel++) { + Elf_Addr *where = (Elf_Addr *) + (obj->relocbase + rel->r_offset); + *where += (Elf_Addr) obj->relocbase; + } + } + + /* Process the PLT relocations with addend if there are any. */ + relalim = (const Elf_Rela *) ((caddr_t) obj->pltrela + + obj->pltrelasize); + if (bind_now) { + /* Fully resolve procedure addresses now */ + for (rela = obj->pltrela; obj->pltrela != NULL && rela < relalim; + rel++) { + Elf_Addr *where = (Elf_Addr *) (obj->relocbase + + rela->r_offset); + const Elf_Sym *def; + const Obj_Entry *defobj; + + assert(ELF_R_TYPE(rela->r_info) == R_ALPHA_JMP_SLOT); + + def = find_symdef(ELF_R_SYM(rela->r_info), obj, &defobj, true); + if (def == NULL) + return -1; + + *where = (Elf_Addr) (defobj->relocbase + def->st_value); + } + } else { /* Just relocate the GOT slots pointing into the PLT */ + for (rela = obj->pltrela; obj->pltrela != NULL && rela < relalim; + rela++) { + Elf_Addr *where = (Elf_Addr *) + (obj->relocbase + rela->r_offset); + *where += (Elf_Addr) obj->relocbase; + } + } + return 0; +} + +/* Process an R_ALPHA_COPY relocation. */ +static int +do_copy_relocation(Obj_Entry *dstobj, const Elf_Rela *rela) +{ + void *dstaddr; + const Elf_Sym *dstsym; + const char *name; + unsigned long hash; + size_t size; + const void *srcaddr; + const Elf_Sym *srcsym; + Obj_Entry *srcobj; + + 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; +} + +/* + * Process the special R_ALPHA_COPY relocations in the main program. These + * copy data from a shared object into a region in the main program's BSS + * segment. + * + * Returns 0 on success, -1 on failure. + */ +int +do_copy_relocations(Obj_Entry *dstobj) +{ + const Elf_Rel *rellim; + const Elf_Rel *rel; + const Elf_Rela *relalim; + const Elf_Rela *rela; + + assert(dstobj->mainprog); /* COPY relocations are invalid elsewhere */ + + rellim = (const Elf_Rel *) ((caddr_t) dstobj->rel + dstobj->relsize); + for (rel = dstobj->rel; dstobj->rel != NULL && rel < rellim; rel++) { + if (ELF_R_TYPE(rel->r_info) == R_ALPHA_COPY) { + Elf_Rela locrela; + + locrela.r_info = rel->r_info; + locrela.r_offset = rel->r_offset; + locrela.r_addend = 0; + if (do_copy_relocation(dstobj, &locrela)) + return -1; + } + } + + relalim = (const Elf_Rela *) ((caddr_t) dstobj->rela + + dstobj->relasize); + for (rela = dstobj->rela; dstobj->rela != NULL && rela < relalim; + rela++) { + if (ELF_R_TYPE(rela->r_info) == R_ALPHA_COPY) { + if (do_copy_relocation(dstobj, rela)) + return -1; + } + } + + return 0; +} |