diff options
Diffstat (limited to 'ext/libelf/libelf_phdr.c')
| -rw-r--r-- | ext/libelf/libelf_phdr.c | 154 |
1 files changed, 154 insertions, 0 deletions
diff --git a/ext/libelf/libelf_phdr.c b/ext/libelf/libelf_phdr.c new file mode 100644 index 000000000..1d7e90bca --- /dev/null +++ b/ext/libelf/libelf_phdr.c @@ -0,0 +1,154 @@ +/*- + * Copyright (c) 2006 Joseph Koshy + * 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. + * + * $FreeBSD: src/lib/libelf/libelf_phdr.c,v 1.2 2006/12/25 02:22:22 jkoshy Exp $ + */ + +#include <assert.h> +#include <stdlib.h> + +#include "gelf.h" +#include "libelf.h" +#include "_libelf.h" + +void * +_libelf_getphdr(Elf *e, int ec) +{ + size_t phnum, phentsize; + size_t fsz, msz; + uint64_t phoff; + Elf32_Ehdr *eh32; + Elf64_Ehdr *eh64; + void *ehdr, *phdr; + void (*xlator)(char *_d, char *_s, size_t _c, int _swap); + + assert(ec == ELFCLASS32 || ec == ELFCLASS64); + + if (e == NULL) { + LIBELF_SET_ERROR(ARGUMENT, 0); + return (NULL); + } + + if ((phdr = (ec == ELFCLASS32 ? + (void *) e->e_u.e_elf.e_phdr.e_phdr32 : + (void *) e->e_u.e_elf.e_phdr.e_phdr64)) != NULL) + return (phdr); + + /* + * Check the PHDR related fields in the EHDR for sanity. + */ + + if ((ehdr = _libelf_ehdr(e, ec, 0)) == NULL) + return (NULL); + + phnum = e->e_u.e_elf.e_nphdr; + + if (ec == ELFCLASS32) { + eh32 = (Elf32_Ehdr *) ehdr; + phentsize = eh32->e_phentsize; + phoff = (uint64_t) eh32->e_phoff; + } else { + eh64 = (Elf64_Ehdr *) ehdr; + phentsize = eh64->e_phentsize; + phoff = (uint64_t) eh64->e_phoff; + } + + fsz = gelf_fsize(e, ELF_T_PHDR, phnum, e->e_version); + + assert(fsz > 0); + + if ((uint64_t) e->e_rawsize < (phoff + fsz)) { + LIBELF_SET_ERROR(HEADER, 0); + return (NULL); + } + + msz = _libelf_msize(ELF_T_PHDR, ec, EV_CURRENT); + + assert(msz > 0); + + if ((phdr = calloc(phnum, msz)) == NULL) { + LIBELF_SET_ERROR(RESOURCE, 0); + return (NULL); + } + + if (ec == ELFCLASS32) + e->e_u.e_elf.e_phdr.e_phdr32 = phdr; + else + e->e_u.e_elf.e_phdr.e_phdr64 = phdr; + + + xlator = _libelf_get_translator(ELF_T_PHDR, ELF_TOMEMORY, ec); + (*xlator)(phdr, e->e_rawfile + phoff, phnum, + e->e_byteorder != LIBELF_PRIVATE(byteorder)); + + return (phdr); +} + +void * +_libelf_newphdr(Elf *e, int ec, size_t count) +{ + void *ehdr, *newphdr, *oldphdr; + size_t msz; + + if (e == NULL) { + LIBELF_SET_ERROR(ARGUMENT, 0); + return (NULL); + } + + if ((ehdr = _libelf_ehdr(e, ec, 0)) == NULL) { + LIBELF_SET_ERROR(SEQUENCE, 0); + return (NULL); + } + + assert(e->e_class == ec); + assert(ec == ELFCLASS32 || ec == ELFCLASS64); + assert(e->e_version == EV_CURRENT); + + msz = _libelf_msize(ELF_T_PHDR, ec, e->e_version); + + assert(msz > 0); + + newphdr = NULL; + if (count > 0 && (newphdr = calloc(count, msz)) == NULL) { + LIBELF_SET_ERROR(RESOURCE, 0); + return (NULL); + } + + if (ec == ELFCLASS32) { + if ((oldphdr = (void *) e->e_u.e_elf.e_phdr.e_phdr32) != NULL) + free(oldphdr); + e->e_u.e_elf.e_phdr.e_phdr32 = (Elf32_Phdr *) newphdr; + } else { + if ((oldphdr = (void *) e->e_u.e_elf.e_phdr.e_phdr64) != NULL) + free(oldphdr); + e->e_u.e_elf.e_phdr.e_phdr64 = (Elf64_Phdr *) newphdr; + } + + e->e_u.e_elf.e_nphdr = count; + + elf_flagphdr(e, ELF_C_SET, ELF_F_DIRTY); + + return (newphdr); +} |