ext/libelf/gelf_phdr.c

/*-
 * 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.
 */

#include <limits.h>

#include "gelf.h"
#include "libelf.h"

#include "_libelf.h"

Elf32_Phdr *
elf32_getphdr(Elf *e)
{
        return (_libelf_getphdr(e, ELFCLASS32));
}

Elf64_Phdr *
elf64_getphdr(Elf *e)
{
        return (_libelf_getphdr(e, ELFCLASS64));
}

GElf_Phdr *
gelf_getphdr(Elf *e, int index, GElf_Phdr *d)
{
        int ec;
        Elf32_Ehdr *eh32;
        Elf64_Ehdr *eh64;
        Elf32_Phdr *ep32;
        Elf64_Phdr *ep64;

        if (d == NULL || e == NULL ||
            ((ec = e->e_class) != ELFCLASS32 && ec != ELFCLASS64) ||
            (e->e_kind != ELF_K_ELF) || index < 0) {
                LIBELF_SET_ERROR(ARGUMENT, 0);
                return (NULL);
        }

        if (ec == ELFCLASS32) {
                if ((eh32 = _libelf_ehdr(e, ELFCLASS32, 0)) == NULL ||
                    ((ep32 = _libelf_getphdr(e, ELFCLASS32)) == NULL))
                        return (NULL);

                if (index >= eh32->e_phnum) {
                        LIBELF_SET_ERROR(ARGUMENT, 0);
                        return (NULL);
                }

                ep32 += index;

                d->p_type   = ep32->p_type;
                d->p_offset = ep32->p_offset;
                d->p_vaddr  = (Elf64_Addr) ep32->p_vaddr;
                d->p_paddr  = (Elf64_Addr) ep32->p_paddr;
                d->p_filesz = (Elf64_Xword) ep32->p_filesz;
                d->p_memsz  = (Elf64_Xword) ep32->p_memsz;
                d->p_flags  = ep32->p_flags;
                d->p_align  = (Elf64_Xword) ep32->p_align;

        } else {
                if ((eh64 = _libelf_ehdr(e, ELFCLASS64, 0)) == NULL ||
                    (ep64 = _libelf_getphdr(e, ELFCLASS64)) == NULL)
                        return (NULL);

                if (index >= eh64->e_phnum) {
                        LIBELF_SET_ERROR(ARGUMENT, 0);
                        return (NULL);
                }

                ep64 += index;

                *d = *ep64;
        }

        return (d);
}

Elf32_Phdr *
elf32_newphdr(Elf *e, size_t count)
{
        return (_libelf_newphdr(e, ELFCLASS32, count));
}

Elf64_Phdr *
elf64_newphdr(Elf *e, size_t count)
{
        return (_libelf_newphdr(e, ELFCLASS64, count));
}

void *
gelf_newphdr(Elf *e, size_t count)
{
        if (e == NULL) {
                LIBELF_SET_ERROR(ARGUMENT, 0);
                return (NULL);
        }
        return (_libelf_newphdr(e, e->e_class, count));
}

int
gelf_update_phdr(Elf *e, int ndx, GElf_Phdr *s)
{
        int ec, phnum;
        void *ehdr;
        Elf32_Phdr *ph32;
        Elf64_Phdr *ph64;

        if (s == NULL || e == NULL || e->e_kind != ELF_K_ELF ||
            ((ec = e->e_class) != ELFCLASS32 && ec != ELFCLASS64)) {
                LIBELF_SET_ERROR(ARGUMENT, 0);
                return (0);
        }

        if (e->e_cmd == ELF_C_READ) {
                LIBELF_SET_ERROR(MODE, 0);
                return (0);
        }

        if ((ehdr = _libelf_ehdr(e, ec, 0)) == NULL)
                return (0);

        if (ec == ELFCLASS32)
                phnum = ((Elf32_Ehdr *) ehdr)->e_phnum;
        else
                phnum = ((Elf64_Ehdr *) ehdr)->e_phnum;

        if (ndx < 0 || ndx > phnum) {
                LIBELF_SET_ERROR(ARGUMENT, 0);
                return (0);
        }

        if (ec == ELFCLASS64) {
                ph64 = e->e_u.e_elf.e_phdr.e_phdr64 + ndx;
                *ph64 = *s;
                return (1);
        }

        ph32 = e->e_u.e_elf.e_phdr.e_phdr32 + ndx;

        ph32->p_type     =  s->p_type;
        ph32->p_flags    =  s->p_flags;
        LIBELF_COPY_U32(ph32, s, p_offset);
        LIBELF_COPY_U32(ph32, s, p_vaddr);
        LIBELF_COPY_U32(ph32, s, p_paddr);
        LIBELF_COPY_U32(ph32, s, p_filesz);
        LIBELF_COPY_U32(ph32, s, p_memsz);
        LIBELF_COPY_U32(ph32, s, p_align);

        (void) elf_flagphdr(e, ELF_C_SET, ELF_F_DIRTY);

        return (1);
}