NetBSD/sys/compat/common/compat_util.c
dholland 8f6ed30d57 Introduce struct pathbuf. This is an abstraction to hold a pathname
and the metadata required to interpret it. Callers of namei must now
create a pathbuf and pass it to NDINIT (instead of a string and a
uio_seg), then destroy the pathbuf after the namei session is
complete.

Update all namei call sites accordingly. Add a pathbuf(9) man page and
update namei(9).

The pathbuf interface also now appears in a couple of related
additional places that were passing string/uio_seg pairs that were
later fed into NDINIT. Update other call sites accordingly.
2010-11-19 06:44:33 +00:00

232 lines
7.1 KiB
C

/* $NetBSD: compat_util.c,v 1.44 2010/11/19 06:44:35 dholland Exp $ */
/*-
* Copyright (c) 1994 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Christos Zoulas and Frank van der Linden.
*
* 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 NETBSD FOUNDATION, INC. 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 FOUNDATION 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.
*/
/*
* Copyright (c) 2008, 2009 Matthew R. Green
* 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. 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.
*/
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: compat_util.c,v 1.44 2010/11/19 06:44:35 dholland Exp $");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/namei.h>
#include <sys/proc.h>
#include <sys/file.h>
#include <sys/stat.h>
#include <sys/filedesc.h>
#include <sys/exec.h>
#include <sys/ioctl.h>
#include <sys/kernel.h>
#include <sys/malloc.h>
#include <sys/vnode.h>
#include <sys/syslog.h>
#include <sys/mount.h>
#include <compat/common/compat_util.h>
void
emul_find_root(struct lwp *l, struct exec_package *epp)
{
struct vnode *vp;
const char *emul_path;
if (epp->ep_emul_root != NULL)
/* We've already found it */
return;
emul_path = epp->ep_esch->es_emul->e_path;
if (emul_path == NULL)
/* Emulation doesn't have a root */
return;
if (namei_simple_kernel(emul_path, NSM_FOLLOW_NOEMULROOT, &vp) != 0)
/* emulation root doesn't exist */
return;
epp->ep_emul_root = vp;
}
/*
* Search the alternate path for dynamic binary interpreter. If not found
* there, check if the interpreter exists in within 'proper' tree.
*/
int
emul_find_interp(struct lwp *l, struct exec_package *epp, const char *itp)
{
int error;
struct pathbuf *pb;
struct nameidata nd;
unsigned int flags;
pb = pathbuf_create(itp);
if (pb == NULL) {
return ENOMEM;
}
/* If we haven't found the emulation root already, do so now */
/* Maybe we should remember failures somehow ? */
if (epp->ep_esch->es_emul->e_path != 0 && epp->ep_emul_root == NULL)
emul_find_root(l, epp);
if (epp->ep_interp != NULL)
vrele(epp->ep_interp);
/* We need to use the emulation root for the new program,
* not the one for the current process. */
if (epp->ep_emul_root == NULL)
flags = FOLLOW;
else {
nd.ni_erootdir = epp->ep_emul_root;
/* hack: Pass in the emulation path for ktrace calls */
nd.ni_next = epp->ep_esch->es_emul->e_path;
flags = FOLLOW | TRYEMULROOT | EMULROOTSET;
}
NDINIT(&nd, LOOKUP, flags, pb);
error = namei(&nd);
if (error != 0) {
epp->ep_interp = NULL;
return error;
}
/* Save interpreter in case we actually need to load it */
epp->ep_interp = nd.ni_vp;
pathbuf_destroy(pb);
return 0;
}
/*
* Translate one set of flags to another, based on the entries in
* the given table. If 'leftover' is specified, it is filled in
* with any flags which could not be translated.
*/
unsigned long
emul_flags_translate(const struct emul_flags_xtab *tab,
unsigned long in, unsigned long *leftover)
{
unsigned long out;
for (out = 0; tab->omask != 0; tab++) {
if ((in & tab->omask) == tab->oval) {
in &= ~tab->omask;
out |= tab->nval;
}
}
if (leftover != NULL)
*leftover = in;
return (out);
}
void
compat_offseterr(struct vnode *vp, const char *msg)
{
struct mount *mp;
mp = vp->v_mount;
log(LOG_ERR, "%s: dir offset too large on fs %s (mounted from %s)\n",
msg, mp->mnt_stat.f_mntonname, mp->mnt_stat.f_mntfromname);
uprintf("%s: dir offset too large for emulated program\n", msg);
}
/*
* Look for native NetBSD compatibility libraries, usually interp-ABI.
* It returns 0 if it changed the interpreter, otherwise it returns
* the error from namei(). Callers should not try any more processing
* if this returns 0, and probably should just ignore the return value.
*/
int
compat_elf_check_interp(struct exec_package *epp,
char *interp,
const char *interp_suffix)
{
int error = 0;
/*
* Don't look for something else, if someone has already found and
* setup the ep_interp already.
*/
if (interp && epp->ep_interp == NULL) {
/*
* If the path is exactly "/usr/libexec/ld.elf_so", first
* try to see if "/usr/libexec/ld.elf_so-<abi>" exists
* and if so, use that instead.
*/
if (strcmp(interp, "/usr/libexec/ld.elf_so") == 0 ||
strcmp(interp, "/libexec/ld.elf_so") == 0) {
struct vnode *vp;
char *path;
path = PNBUF_GET();
snprintf(path, MAXPATHLEN, "%s-%s", interp, interp_suffix);
error = namei_simple_kernel(path,
NSM_FOLLOW_NOEMULROOT, &vp);
/*
* If that worked, replace interpreter in case we
* actually need to load it.
*/
if (error == 0) {
epp->ep_interp = vp;
snprintf(interp, MAXPATHLEN, "%s", path);
}
PNBUF_PUT(path);
}
}
return error;
}