heimdal/lib/kafs/afssys.c

/*
 * Copyright (c) 1995, 1996, 1997 Kungliga Tekniska Högskolan
 * (Royal Institute of Technology, Stockholm, Sweden).
 * 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.
 * 
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *      This product includes software developed by the Kungliga Tekniska
 *      Högskolan and its contributors.
 * 
 * 4. Neither the name of the Institute nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE 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 INSTITUTE 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 "config.h"
#include "protos.h"

RCSID("$Id$");

#include <string.h>
#include <signal.h>
#include <setjmp.h>
#include <errno.h>

#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif
#ifdef HAVE_SYS_TYPES_H
#include <sys/types.h>
#endif
#ifdef HAVE_SYS_IOCTL_H
#include <sys/ioctl.h>
#endif
#ifdef HAVE_SYS_FILIO_H
#include <sys/filio.h>
#endif
#ifdef HAVE_SYS_SYSCALL_H
#include <sys/syscall.h>
#endif
#ifdef HAVE_SYS_SOCKET_H
#include <sys/socket.h>
#endif

#include <kafs.h>

#include "afssysdefs.h"

/* Magic to get AIX syscalls to work */
#ifdef _AIX

static int (*Pioctl)(char*, int, void*, int);
static int (*Setpag)(void);

#include "dlfcn.h"

static
int
isSuid()
{
  int uid = getuid();
  int gid = getgid();
  int euid = getegid();
  int egid = getegid();
  return (uid != euid) || (gid != egid);
}

static
int
aix_setup(void)
{
#ifdef STATIC_AFS_SYSCALLS
    Pioctl = aix_pioctl;
    Setpag = aix_setpag;
#else
    void *ptr;
    char path[MaxPathLen], *p;
    /*
     * If we are root or running setuid don't trust AFSLIBPATH!
     */
    if (getuid() != 0 && !isSuid() && (p = getenv("AFSLIBPATH")) != NULL)
	strcpy(path, p);
    else
	sprintf(path, "%s/afslib.so", LIBDIR);
	
    ptr = dlopen(path, 0);
    if(ptr){
	Setpag = (int (*)(void))dlsym(ptr, "aix_setpag");
	Pioctl = (int (*)(char*, int, void*, int))dlsym(ptr, "aix_pioctl");
    }
#endif
}
#endif

#define NO_ENTRY_POINT		0
#define SINGLE_ENTRY_POINT	1
#define MULTIPLE_ENTRY_POINT	2
#define SINGLE_ENTRY_POINT2	3
#define SINGLE_ENTRY_POINT3	4
#define AIX_ENTRY_POINTS	5
#define UNKNOWN_ENTRY_POINT	6
static int afs_entry_point = UNKNOWN_ENTRY_POINT;

int
k_pioctl(char *a_path,
	 int o_opcode,
	 struct ViceIoctl *a_paramsP,
	 int a_followSymlinks)
{
#ifndef NO_AFS
#ifdef AFS_SYSCALL
  if (afs_entry_point == SINGLE_ENTRY_POINT)
    return syscall(AFS_SYSCALL, AFSCALL_PIOCTL,
		   a_path, o_opcode, a_paramsP, a_followSymlinks);
#endif

#ifdef AFS_PIOCTL
    if (afs_entry_point == MULTIPLE_ENTRY_POINT)
      return syscall(AFS_PIOCTL,
		     a_path, o_opcode, a_paramsP, a_followSymlinks);
#endif

#ifdef AFS_SYSCALL2
  if (afs_entry_point == SINGLE_ENTRY_POINT2)
    return syscall(AFS_SYSCALL2, AFSCALL_PIOCTL,
		   a_path, o_opcode, a_paramsP, a_followSymlinks);
#endif

#ifdef AFS_SYSCALL3
  if (afs_entry_point == SINGLE_ENTRY_POINT3)
    return syscall(AFS_SYSCALL3, AFSCALL_PIOCTL,
		   a_path, o_opcode, a_paramsP, a_followSymlinks);
#endif

#ifdef _AIX
  if (afs_entry_point == AIX_ENTRY_POINTS)
      return Pioctl(a_path, o_opcode, a_paramsP, a_followSymlinks);
#endif

  errno = ENOSYS;
#ifdef SIGSYS
  kill(getpid(), SIGSYS);	/* You loose! */
#endif
#endif /* NO_AFS */
  return -1;
}

int
k_afs_cell_of_file(const char *path, char *cell, int len)
{
    struct ViceIoctl parms;
    parms.in = NULL;
    parms.in_size = 0;
    parms.out = cell;
    parms.out_size = len;
    return k_pioctl((char*)path, VIOC_FILE_CELL_NAME, &parms, 1);
}

int
k_unlog(void)
{
  struct ViceIoctl parms;
  memset(&parms, 0, sizeof(parms));
  return k_pioctl(0, VIOCUNLOG, &parms, 0);
}

int
k_setpag(void)
{
#ifndef NO_AFS
#ifdef AFS_SYSCALL
  if (afs_entry_point == SINGLE_ENTRY_POINT)
    return syscall(AFS_SYSCALL, AFSCALL_SETPAG);
#endif

#ifdef AFS_SETPAG
  if (afs_entry_point == MULTIPLE_ENTRY_POINT)
    return syscall(AFS_SETPAG);
#endif

#ifdef AFS_SYSCALL2
  if (afs_entry_point == SINGLE_ENTRY_POINT2)
    return syscall(AFS_SYSCALL2, AFSCALL_SETPAG);
#endif

#ifdef AFS_SYSCALL3
  if (afs_entry_point == SINGLE_ENTRY_POINT3)
    return syscall(AFS_SYSCALL3, AFSCALL_SETPAG);
#endif

#ifdef _AIX
  if (afs_entry_point == AIX_ENTRY_POINTS)
      return Setpag();
#endif

  errno = ENOSYS;
#ifdef SIGSYS
  kill(getpid(), SIGSYS);	/* You loose! */
#endif
#endif /* NO_AFS */
  return -1;
}

static jmp_buf catch_SIGSYS;

#ifdef SIGSYS

static RETSIGTYPE
SIGSYS_handler(int sig)
{
  errno = 0;
  signal(SIGSYS, SIGSYS_handler); /* Need to reinstall handler on SYSV */
  longjmp(catch_SIGSYS, 1);
}

#endif

int
k_hasafs(void)
{
  int saved_errno;
  RETSIGTYPE (*saved_func)();
  struct ViceIoctl parms;
  
  /*
   * Already checked presence of AFS syscalls?
   */
  if (afs_entry_point != UNKNOWN_ENTRY_POINT)
    return afs_entry_point != NO_ENTRY_POINT;

  /*
   * Probe kernel for AFS specific syscalls,
   * they (currently) come in two flavors.
   * If the syscall is absent we recive a SIGSYS.
   */
  afs_entry_point = NO_ENTRY_POINT;
  memset(&parms, 0, sizeof(parms));
  
  saved_errno = errno;
#ifndef NO_AFS
#ifdef SIGSYS
  saved_func = signal(SIGSYS, SIGSYS_handler);
#endif

#ifdef AFS_SYSCALL
  if (setjmp(catch_SIGSYS) == 0)
    {
      syscall(AFS_SYSCALL, AFSCALL_PIOCTL,
	      0, VIOCSETTOK, &parms, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0);
      if (errno == EINVAL)
	{
	  afs_entry_point = SINGLE_ENTRY_POINT;
	  goto done;
	}
    }
#endif /* AFS_SYSCALL */

#ifdef AFS_PIOCTL
  if (setjmp(catch_SIGSYS) == 0)
    {
      syscall(AFS_PIOCTL,
	      0, VIOCSETTOK, &parms, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0);
      if (errno == EINVAL)
	{
	  afs_entry_point = MULTIPLE_ENTRY_POINT;
	  goto done;
	}
    }
#endif /* AFS_PIOCTL */

#ifdef AFS_SYSCALL2
  if (setjmp(catch_SIGSYS) == 0)
    {
      syscall(AFS_SYSCALL2, AFSCALL_PIOCTL,
	      0, VIOCSETTOK, &parms, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0);
      if (errno == EINVAL)
	{
	  afs_entry_point = SINGLE_ENTRY_POINT2;
	  goto done;
	}
    }
#endif /* AFS_SYSCALL */

#ifdef AFS_SYSCALL3
  if (setjmp(catch_SIGSYS) == 0)
    {
      syscall(AFS_SYSCALL3, AFSCALL_PIOCTL,
	      0, VIOCSETTOK, &parms, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0);
      if (errno == EINVAL)
	{
	  afs_entry_point = SINGLE_ENTRY_POINT3;
	  goto done;
	}
    }
#endif /* AFS_SYSCALL */

#ifdef _AIX
  aix_setup();
  if(Pioctl != NULL && Setpag != NULL){
      afs_entry_point = AIX_ENTRY_POINTS;
      goto done;
  }
#endif

 done:
#ifdef SIGSYS
  signal(SIGSYS, saved_func);
#endif
#endif /* NO_AFS */
  errno = saved_errno;
  return afs_entry_point != NO_ENTRY_POINT;
}