Home | History | Annotate | Line # | Download | only in vax
mdreloc.c revision 1.6
      1  1.1  mycroft #include <sys/types.h>
      2  1.1  mycroft #include <sys/stat.h>
      3  1.1  mycroft 
      4  1.1  mycroft #include "debug.h"
      5  1.1  mycroft #include "rtld.h"
      6  1.1  mycroft 
      7  1.1  mycroft void
      8  1.1  mycroft _rtld_setup_pltgot(const Obj_Entry *obj)
      9  1.1  mycroft {
     10  1.1  mycroft 	obj->pltgot[1] = (Elf_Addr) obj;
     11  1.1  mycroft 	obj->pltgot[2] = (Elf_Addr) &_rtld_bind_start;
     12  1.1  mycroft }
     13  1.2  mycroft 
     14  1.2  mycroft int
     15  1.3  mycroft _rtld_relocate_nonplt_objects(obj, dodebug)
     16  1.2  mycroft 	Obj_Entry *obj;
     17  1.2  mycroft 	bool dodebug;
     18  1.2  mycroft {
     19  1.3  mycroft 	const Elf_Rela *rela;
     20  1.2  mycroft 
     21  1.3  mycroft 	for (rela = obj->rela; rela < obj->relalim; rela++) {
     22  1.3  mycroft 		Elf_Addr        *where;
     23  1.3  mycroft 		const Elf_Sym   *def;
     24  1.3  mycroft 		const Obj_Entry *defobj;
     25  1.3  mycroft 		Elf_Addr         tmp;
     26  1.4  mycroft 		unsigned long	 symnum;
     27  1.3  mycroft 
     28  1.3  mycroft 		where = (Elf_Addr *)(obj->relocbase + rela->r_offset);
     29  1.4  mycroft 		symnum = ELF_R_SYM(rela->r_info);
     30  1.3  mycroft 
     31  1.3  mycroft 		switch (ELF_R_TYPE(rela->r_info)) {
     32  1.3  mycroft 		case R_TYPE(NONE):
     33  1.3  mycroft 			break;
     34  1.3  mycroft 
     35  1.3  mycroft 		case R_TYPE(32):	/* word32 S + A */
     36  1.3  mycroft 		case R_TYPE(GLOB_DAT):	/* word32 S + A */
     37  1.4  mycroft 			def = _rtld_find_symdef(symnum, obj, &defobj, false);
     38  1.3  mycroft 			if (def == NULL)
     39  1.3  mycroft 				return -1;
     40  1.3  mycroft 
     41  1.3  mycroft 			tmp = (Elf_Addr)(defobj->relocbase + def->st_value +
     42  1.3  mycroft 			    rela->r_addend);
     43  1.3  mycroft 
     44  1.3  mycroft 			if (*where != tmp)
     45  1.3  mycroft 				*where = tmp;
     46  1.3  mycroft 			rdbg(dodebug, ("32/GLOB_DAT %s in %s --> %p in %s",
     47  1.5  mycroft 			    obj->strtab + obj->symtab[symnum].st_name,
     48  1.5  mycroft 			    obj->path, (void *)*where, defobj->path));
     49  1.3  mycroft 			break;
     50  1.3  mycroft 
     51  1.3  mycroft 		case R_TYPE(RELATIVE):	/* word32 B + A */
     52  1.3  mycroft 			tmp = (Elf_Addr)(obj->relocbase + rela->r_addend);
     53  1.3  mycroft 			if (*where != tmp)
     54  1.3  mycroft 				*where = tmp;
     55  1.3  mycroft 			rdbg(dodebug, ("RELATIVE in %s --> %p", obj->path,
     56  1.3  mycroft 			    (void *)*where));
     57  1.3  mycroft 			break;
     58  1.3  mycroft 
     59  1.3  mycroft 		case R_TYPE(COPY):
     60  1.3  mycroft 			/*
     61  1.3  mycroft 			 * These are deferred until all other relocations have
     62  1.3  mycroft 			 * been done.  All we do here is make sure that the
     63  1.3  mycroft 			 * COPY relocation is not in a shared library.  They
     64  1.3  mycroft 			 * are allowed only in executable files.
     65  1.3  mycroft 			 */
     66  1.3  mycroft 			if (!obj->mainprog) {
     67  1.3  mycroft 				_rtld_error(
     68  1.2  mycroft 			"%s: Unexpected R_COPY relocation in shared library",
     69  1.3  mycroft 				    obj->path);
     70  1.3  mycroft 				return -1;
     71  1.3  mycroft 			}
     72  1.3  mycroft 			rdbg(dodebug, ("COPY (avoid in main)"));
     73  1.3  mycroft 			break;
     74  1.3  mycroft 
     75  1.3  mycroft 		default:
     76  1.3  mycroft 			rdbg(dodebug, ("sym = %lu, type = %lu, offset = %p, "
     77  1.3  mycroft 			    "addend = %p, contents = %p, symbol = %s",
     78  1.4  mycroft 			    symnum, (u_long)ELF_R_TYPE(rela->r_info),
     79  1.3  mycroft 			    (void *)rela->r_offset, (void *)rela->r_addend,
     80  1.3  mycroft 			    (void *)*where,
     81  1.4  mycroft 			    obj->strtab + obj->symtab[symnum].st_name));
     82  1.3  mycroft 			_rtld_error("%s: Unsupported relocation type %ld "
     83  1.3  mycroft 			    "in non-PLT relocations\n",
     84  1.3  mycroft 			    obj->path, (u_long) ELF_R_TYPE(rela->r_info));
     85  1.2  mycroft 			return -1;
     86  1.2  mycroft 		}
     87  1.2  mycroft 	}
     88  1.2  mycroft 	return 0;
     89  1.2  mycroft }
     90  1.6  mycroft 
     91  1.6  mycroft int
     92  1.6  mycroft _rtld_relocate_plt_lazy(obj, dodebug)
     93  1.6  mycroft 	Obj_Entry *obj;
     94  1.6  mycroft 	bool dodebug;
     95  1.6  mycroft {
     96  1.6  mycroft 	const Elf_Rela *rela;
     97  1.6  mycroft 
     98  1.6  mycroft 	if (obj->mainprog)
     99  1.6  mycroft 		return 0;
    100  1.6  mycroft 
    101  1.6  mycroft 	for (rela = obj->pltrela; rela < obj->pltrelalim; rela++) {
    102  1.6  mycroft 		Elf_Addr *where = (Elf_Addr *)(obj->relocbase + rela->r_offset);
    103  1.6  mycroft 
    104  1.6  mycroft 		assert(ELF_R_TYPE(rela->r_info) == R_TYPE(JMP_SLOT));
    105  1.6  mycroft 
    106  1.6  mycroft 		/* Just relocate the GOT slots pointing into the PLT */
    107  1.6  mycroft 		*where += (Elf_Addr)obj->relocbase;
    108  1.6  mycroft 		rdbg(dodebug, ("fixup !main in %s --> %p", obj->path,
    109  1.6  mycroft 		    (void *)*where));
    110  1.6  mycroft 	}
    111  1.6  mycroft 
    112  1.6  mycroft 	return 0;
    113  1.6  mycroft }
    114  1.6  mycroft 
    115  1.6  mycroft int
    116  1.6  mycroft _rtld_relocate_plt_object(obj, rela, addrp, dodebug)
    117  1.6  mycroft 	Obj_Entry *obj;
    118  1.6  mycroft 	const Elf_Rela *rela;
    119  1.6  mycroft 	caddr_t *addrp;
    120  1.6  mycroft 	bool dodebug;
    121  1.6  mycroft {
    122  1.6  mycroft 	Elf_Addr *where = (Elf_Addr *)(obj->relocbase + rela->r_offset);
    123  1.6  mycroft 	Elf_Addr new_value;
    124  1.6  mycroft 	const Elf_Sym  *def;
    125  1.6  mycroft 	const Obj_Entry *defobj;
    126  1.6  mycroft 
    127  1.6  mycroft 	assert(ELF_R_TYPE(rela->r_info) == R_TYPE(JMP_SLOT));
    128  1.6  mycroft 
    129  1.6  mycroft 	def = _rtld_find_symdef(ELF_R_SYM(rela->r_info), obj, &defobj, true);
    130  1.6  mycroft 	if (def == NULL)
    131  1.6  mycroft 		return -1;
    132  1.6  mycroft 
    133  1.6  mycroft 	new_value = (Elf_Addr)(defobj->relocbase + def->st_value +
    134  1.6  mycroft 	    rela->r_addend);
    135  1.6  mycroft 	rdbg(dodebug, ("bind now/fixup in %s --> old=%p new=%p",
    136  1.6  mycroft 	    defobj->strtab + def->st_name, (void *)*where, (void *)new_value));
    137  1.6  mycroft 	if (*where != new_value)
    138  1.6  mycroft 		*where = new_value;
    139  1.6  mycroft 
    140  1.6  mycroft 	*addrp = (caddr_t)(new_value - rela->r_addend);
    141  1.6  mycroft 	return 0;
    142  1.6  mycroft }
    143