freebsd-nq/sys/compat/svr4/svr4_sysvec.c
Robert Watson b1fc0ec1a7 o Merge contents of struct pcred into struct ucred. Specifically, add the
real uid, saved uid, real gid, and saved gid to ucred, as well as the
  pcred->pc_uidinfo, which was associated with the real uid, only rename
  it to cr_ruidinfo so as not to conflict with cr_uidinfo, which
  corresponds to the effective uid.
o Remove p_cred from struct proc; add p_ucred to struct proc, replacing
  original macro that pointed.
  p->p_ucred to p->p_cred->pc_ucred.
o Universally update code so that it makes use of ucred instead of pcred,
  p->p_ucred instead of p->p_pcred, cr_ruidinfo instead of p_uidinfo,
  cr_{r,sv}{u,g}id instead of p_*, etc.
o Remove pcred0 and its initialization from init_main.c; initialize
  cr_ruidinfo there.
o Restruction many credential modification chunks to always crdup while
  we figure out locking and optimizations; generally speaking, this
  means moving to a structure like this:
        newcred = crdup(oldcred);
        ...
        p->p_ucred = newcred;
        crfree(oldcred);
  It's not race-free, but better than nothing.  There are also races
  in sys_process.c, all inter-process authorization, fork, exec, and
  exit.
o Remove sigio->sio_ruid since sigio->sio_ucred now contains the ruid;
  remove comments indicating that the old arrangement was a problem.
o Restructure exec1() a little to use newcred/oldcred arrangement, and
  use improved uid management primitives.
o Clean up exit1() so as to do less work in credential cleanup due to
  pcred removal.
o Clean up fork1() so as to do less work in credential cleanup and
  allocation.
o Clean up ktrcanset() to take into account changes, and move to using
  suser_xxx() instead of performing a direct uid==0 comparision.
o Improve commenting in various kern_prot.c credential modification
  calls to better document current behavior.  In a couple of places,
  current behavior is a little questionable and we need to check
  POSIX.1 to make sure it's "right".  More commenting work still
  remains to be done.
o Update credential management calls, such as crfree(), to take into
  account new ruidinfo reference.
o Modify or add the following uid and gid helper routines:
      change_euid()
      change_egid()
      change_ruid()
      change_rgid()
      change_svuid()
      change_svgid()
  In each case, the call now acts on a credential not a process, and as
  such no longer requires more complicated process locking/etc.  They
  now assume the caller will do any necessary allocation of an
  exclusive credential reference.  Each is commented to document its
  reference requirements.
o CANSIGIO() is simplified to require only credentials, not processes
  and pcreds.
o Remove lots of (p_pcred==NULL) checks.
o Add an XXX to authorization code in nfs_lock.c, since it's
  questionable, and needs to be considered carefully.
o Simplify posix4 authorization code to require only credentials, not
  processes and pcreds.  Note that this authorization, as well as
  CANSIGIO(), needs to be updated to use the p_cansignal() and
  p_cansched() centralized authorization routines, as they currently
  do not take into account some desirable restrictions that are handled
  by the centralized routines, as well as being inconsistent with other
  similar authorization instances.
o Update libkvm to take these changes into account.

Obtained from:	TrustedBSD Project
Reviewed by:	green, bde, jhb, freebsd-arch, freebsd-audit
2001-05-25 16:59:11 +00:00

409 lines
10 KiB
C

/*
* Copyright (c) 1998 Mark Newton
* 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 Christos Zoulas.
* 4. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 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.
*
* $FreeBSD$
*/
/* XXX we use functions that might not exist. */
#include "opt_compat.h"
#ifndef COMPAT_43
#error "Unable to compile SVR4-emulator due to missing COMPAT_43 option!"
#endif
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/proc.h>
#include <sys/sysent.h>
#include <sys/imgact.h>
#include <sys/imgact_elf.h>
#include <sys/socket.h>
#include <sys/malloc.h>
#include <sys/namei.h>
#include <sys/vnode.h>
#include <sys/module.h>
#include <vm/vm.h>
#include <sys/exec.h>
#include <sys/kernel.h>
#include <machine/cpu.h>
#include <netinet/in.h>
#include <compat/svr4/svr4.h>
#include <compat/svr4/svr4_types.h>
#include <compat/svr4/svr4_syscall.h>
#include <compat/svr4/svr4_signal.h>
#include <compat/svr4/svr4_sockio.h>
#include <compat/svr4/svr4_socket.h>
#include <compat/svr4/svr4_errno.h>
#include <compat/svr4/svr4_proto.h>
#include <compat/svr4/svr4_siginfo.h>
#include <compat/svr4/svr4_util.h>
int bsd_to_svr4_errno[ELAST+1] = {
0,
SVR4_EPERM,
SVR4_ENOENT,
SVR4_ESRCH,
SVR4_EINTR,
SVR4_EIO,
SVR4_ENXIO,
SVR4_E2BIG,
SVR4_ENOEXEC,
SVR4_EBADF,
SVR4_ECHILD,
SVR4_EDEADLK,
SVR4_ENOMEM,
SVR4_EACCES,
SVR4_EFAULT,
SVR4_ENOTBLK,
SVR4_EBUSY,
SVR4_EEXIST,
SVR4_EXDEV,
SVR4_ENODEV,
SVR4_ENOTDIR,
SVR4_EISDIR,
SVR4_EINVAL,
SVR4_ENFILE,
SVR4_EMFILE,
SVR4_ENOTTY,
SVR4_ETXTBSY,
SVR4_EFBIG,
SVR4_ENOSPC,
SVR4_ESPIPE,
SVR4_EROFS,
SVR4_EMLINK,
SVR4_EPIPE,
SVR4_EDOM,
SVR4_ERANGE,
SVR4_EAGAIN,
SVR4_EINPROGRESS,
SVR4_EALREADY,
SVR4_ENOTSOCK,
SVR4_EDESTADDRREQ,
SVR4_EMSGSIZE,
SVR4_EPROTOTYPE,
SVR4_ENOPROTOOPT,
SVR4_EPROTONOSUPPORT,
SVR4_ESOCKTNOSUPPORT,
SVR4_EOPNOTSUPP,
SVR4_EPFNOSUPPORT,
SVR4_EAFNOSUPPORT,
SVR4_EADDRINUSE,
SVR4_EADDRNOTAVAIL,
SVR4_ENETDOWN,
SVR4_ENETUNREACH,
SVR4_ENETRESET,
SVR4_ECONNABORTED,
SVR4_ECONNRESET,
SVR4_ENOBUFS,
SVR4_EISCONN,
SVR4_ENOTCONN,
SVR4_ESHUTDOWN,
SVR4_ETOOMANYREFS,
SVR4_ETIMEDOUT,
SVR4_ECONNREFUSED,
SVR4_ELOOP,
SVR4_ENAMETOOLONG,
SVR4_EHOSTDOWN,
SVR4_EHOSTUNREACH,
SVR4_ENOTEMPTY,
SVR4_EPROCLIM,
SVR4_EUSERS,
SVR4_EDQUOT,
SVR4_ESTALE,
SVR4_EREMOTE,
SVR4_EBADRPC,
SVR4_ERPCMISMATCH,
SVR4_EPROGUNAVAIL,
SVR4_EPROGMISMATCH,
SVR4_EPROCUNAVAIL,
SVR4_ENOLCK,
SVR4_ENOSYS,
SVR4_EFTYPE,
SVR4_EAUTH,
SVR4_ENEEDAUTH,
SVR4_EIDRM,
SVR4_ENOMSG,
};
static int svr4_fixup(register_t **stack_base, struct image_params *imgp);
extern struct sysent svr4_sysent[];
#undef szsigcode
#undef sigcode
extern int svr4_szsigcode;
extern char svr4_sigcode[];
struct sysentvec svr4_sysvec = {
SVR4_SYS_MAXSYSCALL,
svr4_sysent,
0xff,
SVR4_SIGTBLSZ,
bsd_to_svr4_sig,
ELAST, /* ELAST */
bsd_to_svr4_errno,
0,
svr4_fixup,
svr4_sendsig,
svr4_sigcode,
&svr4_szsigcode,
NULL,
"SVR4",
elf_coredump,
NULL,
SVR4_MINSIGSTKSZ
};
Elf32_Brandinfo svr4_brand = {
ELFOSABI_SOLARIS, /* XXX Or should we use ELFOSABI_SYSV here? */
"SVR4",
svr4_emul_path,
"/lib/libc.so.1",
&svr4_sysvec
};
const char svr4_emul_path[] = "/compat/svr4";
static int
svr4_fixup(register_t **stack_base, struct image_params *imgp)
{
Elf32_Auxargs *args = (Elf32_Auxargs *)imgp->auxargs;
register_t *pos;
pos = *stack_base + (imgp->argc + imgp->envc + 2);
if (args->trace) {
AUXARGS_ENTRY(pos, AT_DEBUG, 1);
}
if (args->execfd != -1) {
AUXARGS_ENTRY(pos, AT_EXECFD, args->execfd);
}
AUXARGS_ENTRY(pos, AT_PHDR, args->phdr);
AUXARGS_ENTRY(pos, AT_PHENT, args->phent);
AUXARGS_ENTRY(pos, AT_PHNUM, args->phnum);
AUXARGS_ENTRY(pos, AT_PAGESZ, args->pagesz);
AUXARGS_ENTRY(pos, AT_FLAGS, args->flags);
AUXARGS_ENTRY(pos, AT_ENTRY, args->entry);
AUXARGS_ENTRY(pos, AT_BASE, args->base);
AUXARGS_ENTRY(pos, AT_UID, imgp->proc->p_ucred->cr_ruid);
AUXARGS_ENTRY(pos, AT_EUID, imgp->proc->p_ucred->cr_svuid);
AUXARGS_ENTRY(pos, AT_GID, imgp->proc->p_ucred->cr_rgid);
AUXARGS_ENTRY(pos, AT_EGID, imgp->proc->p_ucred->cr_svgid);
AUXARGS_ENTRY(pos, AT_NULL, 0);
free(imgp->auxargs, M_TEMP);
imgp->auxargs = NULL;
(*stack_base)--;
**stack_base = (int)imgp->argc;
return 0;
}
/*
* Search an alternate path before passing pathname arguments on
* to system calls. Useful for keeping a separate 'emulation tree'.
*
* If cflag is set, we check if an attempt can be made to create
* the named file, i.e. we check if the directory it should
* be in exists.
*
* Code shamelessly stolen by Mark Newton from IBCS2 emulation code.
*/
int
svr4_emul_find(p, sgp, prefix, path, pbuf, cflag)
struct proc *p;
caddr_t *sgp; /* Pointer to stackgap memory */
const char *prefix;
char *path;
char **pbuf;
int cflag;
{
struct nameidata nd;
struct nameidata ndroot;
struct vattr vat;
struct vattr vatroot;
int error;
char *ptr, *buf, *cp;
size_t sz, len;
buf = (char *) malloc(MAXPATHLEN, M_TEMP, M_WAITOK);
*pbuf = path;
for (ptr = buf; (*ptr = *prefix) != '\0'; ptr++, prefix++)
continue;
sz = MAXPATHLEN - (ptr - buf);
/*
* If sgp is not given then the path is already in kernel space
*/
if (sgp == NULL)
error = copystr(path, ptr, sz, &len);
else
error = copyinstr(path, ptr, sz, &len);
if (error) {
free(buf, M_TEMP);
return error;
}
if (*ptr != '/') {
free(buf, M_TEMP);
return EINVAL;
}
/*
* We know that there is a / somewhere in this pathname.
* Search backwards for it, to find the file's parent dir
* to see if it exists in the alternate tree. If it does,
* and we want to create a file (cflag is set). We don't
* need to worry about the root comparison in this case.
*/
if (cflag) {
for (cp = &ptr[len] - 1; *cp != '/'; cp--);
*cp = '\0';
NDINIT(&nd, LOOKUP, FOLLOW, UIO_SYSSPACE, buf, p);
if ((error = namei(&nd)) != 0) {
free(buf, M_TEMP);
return error;
}
NDFREE(&nd, NDF_ONLY_PNBUF);
*cp = '/';
}
else {
NDINIT(&nd, LOOKUP, FOLLOW, UIO_SYSSPACE, buf, p);
if ((error = namei(&nd)) != 0) {
free(buf, M_TEMP);
return error;
}
NDFREE(&nd, NDF_ONLY_PNBUF);
/*
* We now compare the vnode of the svr4_root to the one
* vnode asked. If they resolve to be the same, then we
* ignore the match so that the real root gets used.
* This avoids the problem of traversing "../.." to find the
* root directory and never finding it, because "/" resolves
* to the emulation root directory. This is expensive :-(
*/
NDINIT(&ndroot, LOOKUP, FOLLOW, UIO_SYSSPACE, svr4_emul_path,
p);
if ((error = namei(&ndroot)) != 0) {
/* Cannot happen! */
free(buf, M_TEMP);
vrele(nd.ni_vp);
return error;
}
NDFREE(&ndroot, NDF_ONLY_PNBUF);
if ((error = VOP_GETATTR(nd.ni_vp, &vat, p->p_ucred, p)) != 0) {
goto done;
}
if ((error = VOP_GETATTR(ndroot.ni_vp, &vatroot, p->p_ucred, p))
!= 0) {
goto done;
}
if (vat.va_fsid == vatroot.va_fsid &&
vat.va_fileid == vatroot.va_fileid) {
error = ENOENT;
goto done;
}
}
if (sgp == NULL)
*pbuf = buf;
else {
sz = &ptr[len] - buf;
*pbuf = stackgap_alloc(sgp, sz + 1);
error = copyout(buf, *pbuf, sz);
free(buf, M_TEMP);
}
done:
vrele(nd.ni_vp);
if (!cflag)
vrele(ndroot.ni_vp);
return error;
}
static int
svr4_elf_modevent(module_t mod, int type, void *data)
{
int error;
error = 0;
switch(type) {
case MOD_LOAD:
if (elf_insert_brand_entry(&svr4_brand) < 0)
error = EINVAL;
if (error)
printf("cannot insert svr4 elf brand handler\n");
else if (bootverbose)
printf("svr4 ELF exec handler installed\n");
break;
case MOD_UNLOAD:
/* Only allow the emulator to be removed if it isn't in use. */
if (elf_brand_inuse(&svr4_brand) != 0) {
error = EBUSY;
} else if (elf_remove_brand_entry(&svr4_brand) < 0) {
error = EINVAL;
}
if (error)
printf("Could not deinstall ELF interpreter entry (error %d)\n",
error);
else if (bootverbose)
printf("svr4 ELF exec handler removed\n");
break;
default:
break;
}
return error;
}
static moduledata_t svr4_elf_mod = {
"svr4elf",
svr4_elf_modevent,
0
};
DECLARE_MODULE(svr4elf, svr4_elf_mod, SI_SUB_EXEC, SI_ORDER_ANY);
MODULE_DEPEND(svr4elf, streams, 1, 1, 1);