/* $OpenBSD: boot_md.c,v 1.3 2019/11/10 22:21:54 guenther Exp $ */ /* * Copyright (c) 1998 Per Fogelstrom, Opsycon AB * * 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. * */ /* * IMPORTANT: any functions below are NOT protected by SSP. Please * do not add anything except what is required to reach GOT with * an adjustment. */ #define _DYN_LOADER #include #include "syscall.h" #include "archdep.h" #include "stdlib.h" #include "../../lib/csu/os-note-elf.h" #if RELOC_TAG == DT_RELA typedef Elf_RelA RELOC_TYPE; #elif RELOC_TAG == DT_REL typedef Elf_Rel RELOC_TYPE; #else # error "unknown RELOC_TAG" #endif /* The set of dynamic tags that we're interested in for bootstrapping */ struct boot_dyn { RELOC_TYPE *dt_reloc; /* DT_RELA or DT_REL */ Elf_Addr dt_relocsz; /* DT_RELASZ or DT_RELSZ */ Elf_Addr *dt_pltgot; const Elf_Sym *dt_symtab; #if DT_PROCNUM > 0 u_long dt_proc[DT_PROCNUM]; #endif }; /* * Local decls. */ void _dl_boot_bind(const long, long *, Elf_Dyn *) __boot; void _dl_boot_bind(const long sp, long *dl_data, Elf_Dyn *dynp) { struct boot_dyn dynld; /* Resolver data for the loader */ AuxInfo *auxstack; long *stack; int n, argc; char **argv, **envp; long loff; RELOC_TYPE *rp, *rend; /* * Scan argument and environment vectors. Find dynamic * data vector put after them. */ stack = (long *)sp; argc = *stack++; argv = (char **)stack; envp = &argv[argc + 1]; stack = (long *)envp; while (*stack++ != 0L) ; /* * Zero out dl_data. */ for (n = 0; n <= AUX_entry; n++) dl_data[n] = 0; /* * Dig out auxiliary data set up by exec call. Move all known * tags to an indexed local table for easy access. */ for (auxstack = (AuxInfo *)stack; auxstack->au_id != AUX_null; auxstack++) { if (auxstack->au_id > AUX_entry) continue; dl_data[auxstack->au_id] = auxstack->au_v; } loff = dl_data[AUX_base]; /* XXX assumes ld.so is linked at 0x0 */ /* * We need to do 'selfreloc' in case the code weren't * loaded at the address it was linked to. * * Scan the DYNAMIC section for the loader. * Cache the data for easier access. */ _dl_memset(&dynld, 0, sizeof(dynld)); while (dynp->d_tag != DT_NULL) { /* first the tags that are pointers to be relocated */ if (dynp->d_tag == DT_PLTGOT) dynld.dt_pltgot = (void *)(dynp->d_un.d_ptr + loff); else if (dynp->d_tag == DT_SYMTAB) dynld.dt_symtab = (void *)(dynp->d_un.d_ptr + loff); else if (dynp->d_tag == RELOC_TAG) /* DT_{RELA,REL} */ dynld.dt_reloc = (void *)(dynp->d_un.d_ptr + loff); /* Now for the tags that are just sizes or counts */ else if (dynp->d_tag == RELOC_TAG+1) /* DT_{RELA,REL}SZ */ dynld.dt_relocsz = dynp->d_un.d_val; #if DT_PROCNUM > 0 else if (dynp->d_tag >= DT_LOPROC && dynp->d_tag < DT_LOPROC + DT_PROCNUM) dynld.dt_proc[dynp->d_tag - DT_LOPROC] = dynp->d_un.d_val; #endif /* DT_PROCNUM */ dynp++; } rp = dynld.dt_reloc; rend = (RELOC_TYPE *)((char *)rp + dynld.dt_relocsz); for (; rp < rend; rp++) { if (ELF_R_TYPE(rp->r_info) != R_MIPS_NONE) { Elf_Addr *ra = (Elf_Addr *)(rp->r_offset + loff); *ra += loff; } } RELOC_GOT(&dynld, loff); }