/*

 * Copyright (c) 2009, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 *

 */

#include <link.h>

#include <stdio.h>

#include <stdlib.h>

#include <string.h>

#include <sys/types.h>

#include <sys/stat.h>

#include <fcntl.h>

#include <limits.h>

#include <varargs.h>

// This class sets up an interposer on open calls from libproc.so to

// support a pathmap facility in the SA.

static uintptr_t* libproc_cookie;

static uintptr_t* libc_cookie;

static uintptr_t* libsaproc_cookie;

uint_t

la_version(uint_t version)

{

  return (LAV_CURRENT);

}

uint_t

la_objopen(Link_map * lmp, Lmid_t lmid, uintptr_t * cookie)

{

  if (strstr(lmp->l_name, "/libproc.so") != NULL) {

    libproc_cookie = cookie;

    return LA_FLG_BINDFROM;

  }

  if (strstr(lmp->l_name, "/libc.so") != NULL) {

    libc_cookie = cookie;

    return LA_FLG_BINDTO;

  }

  if (strstr(lmp->l_name, "/libsaproc.so") != NULL) {

    libsaproc_cookie = cookie;

    return LA_FLG_BINDTO | LA_FLG_BINDFROM;

  }

  return 0;

}

#if     defined(_LP64)

uintptr_t

la_symbind64(Elf64_Sym *symp, uint_t symndx, uintptr_t *refcook,

             uintptr_t *defcook, uint_t *sb_flags, const char *sym_name)

#else

uintptr_t

la_symbind32(Elf32_Sym *symp, uint_t symndx, uintptr_t *refcook,

             uintptr_t *defcook, uint_t *sb_flags)

#endif

{

#if     !defined(_LP64)

  const char      *sym_name = (const char *)symp->st_name;

#endif

  if (strcmp(sym_name, "open") == 0 && refcook == libproc_cookie) {

    // redirect all open calls from libproc.so through libsaproc_open which will

    // try the alternate library locations first.

    void* handle = dlmopen(LM_ID_BASE, "libsaproc.so", RTLD_NOLOAD);

    if (handle == NULL) {

      fprintf(stderr, "libsaproc_audit.so: didn't find libsaproc.so during linking\n");

    } else {

      uintptr_t libsaproc_open = (uintptr_t)dlsym(handle, "libsaproc_open");

      if (libsaproc_open == 0) {

        fprintf(stderr, "libsaproc_audit.so: didn't find libsaproc_open during linking\n");

      } else {

        return libsaproc_open;

      }

    }

  }

  return symp->st_value;

}