diff options
Diffstat (limited to 'sys/arch/amd64/stand/efi32/self_reloc.c')
| -rw-r--r-- | sys/arch/amd64/stand/efi32/self_reloc.c | 124 |
1 files changed, 124 insertions, 0 deletions
diff --git a/sys/arch/amd64/stand/efi32/self_reloc.c b/sys/arch/amd64/stand/efi32/self_reloc.c new file mode 100644 index 00000000000..75ccf65bad6 --- /dev/null +++ b/sys/arch/amd64/stand/efi32/self_reloc.c @@ -0,0 +1,124 @@ +/* $OpenBSD: self_reloc.c,v 1.1 2019/05/11 02:33:34 mlarkin Exp $ */ +/*- + * Copyright (c) 2008-2010 Rui Paulo <rpaulo@FreeBSD.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. 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 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 AUTHOR 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. + */ + +#include <sys/param.h> +#include <machine/reloc.h> + +#if defined(__aarch64__) || defined(__amd64__) +#define ELFSIZE 64 +#define ElfW_Rel Elf64_Rela +#define ElfW_Dyn Elf64_Dyn +#define ELFW_R_TYPE ELF64_R_TYPE +#define ELF_RELA +#elif defined(__arm__) || defined(__i386__) +#define ELFSIZE 32 +#define ElfW_Rel Elf32_Rel +#define ElfW_Dyn Elf32_Dyn +#define ELFW_R_TYPE ELF32_R_TYPE +#else +#error architecture not supported +#endif + +#include <sys/exec_elf.h> + +#if defined(__aarch64__) +#define RELOC_TYPE_NONE R_AARCH64_NONE +#define RELOC_TYPE_RELATIVE R_AARCH64_RELATIVE +#elif defined(__amd64__) +#define RELOC_TYPE_NONE R_X86_64_NONE +#define RELOC_TYPE_RELATIVE R_X86_64_RELATIVE +#elif defined(__arm__) +#define RELOC_TYPE_NONE R_ARM_NONE +#define RELOC_TYPE_RELATIVE R_ARM_RELATIVE +#elif defined(__i386__) +#define RELOC_TYPE_NONE R_386_NONE +#define RELOC_TYPE_RELATIVE R_386_RELATIVE +#endif + +/* + * A simple elf relocator. + */ +void +self_reloc(Elf_Addr baseaddr, ElfW_Dyn *dynamic) +{ + Elf_Word relsz, relent; + Elf_Addr *newaddr; + ElfW_Rel *rel = NULL; + ElfW_Dyn *dynp; + + /* + * Find the relocation address, its size and the relocation entry. + */ + relsz = 0; + relent = 0; + for (dynp = dynamic; dynp->d_tag != DT_NULL; dynp++) { + switch (dynp->d_tag) { + case DT_REL: + case DT_RELA: + rel = (ElfW_Rel *)(dynp->d_un.d_ptr + baseaddr); + break; + case DT_RELSZ: + case DT_RELASZ: + relsz = dynp->d_un.d_val; + break; + case DT_RELENT: + case DT_RELAENT: + relent = dynp->d_un.d_val; + break; + default: + break; + } + } + + /* + * Perform the actual relocation. We rely on the object having been + * linked at 0, so that the difference between the load and link + * address is the same as the load address. + */ + for (; relsz > 0; relsz -= relent) { + switch (ELFW_R_TYPE(rel->r_info)) { + case RELOC_TYPE_NONE: + /* No relocation needs be performed. */ + break; + + case RELOC_TYPE_RELATIVE: + newaddr = (Elf_Addr *)(rel->r_offset + baseaddr); +#ifdef ELF_RELA + /* Addend relative to the base address. */ + *newaddr = baseaddr + rel->r_addend; +#else + /* Address relative to the base address. */ + *newaddr += baseaddr; +#endif + break; + default: + /* XXX: do we need other relocations ? */ + break; + } + rel = (ElfW_Rel *) ((caddr_t) rel + relent); + } +} |