ubuntu-buildroot/output/build/host-attr-2.5.1/libattr/libattr.c

468 lines
11 KiB
C

/*
* Copyright (c) 2001-2003,2005 Silicon Graphics, Inc.
* All Rights Reserved.
*
* This program is free software: you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as published
* by the Free Software Foundation, either version 2.1 of the License, or
* (at your option) any later version.
*
* This program 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 Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include "config.h"
#include <errno.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/xattr.h>
#include <attr/attributes.h>
#ifndef ENOATTR
# define ENOATTR ENODATA
#endif
#undef MAXNAMELEN
#define MAXNAMELEN 256
#undef MAXLISTLEN
#define MAXLISTLEN 65536
#undef roundup
#define roundup(x,y) ((((x)+((y)-1))/(y))*(y))
static const char *user_name = "user.";
static const char *secure_name = "security.";
static const char *trusted_name = "trusted.";
static const char *xfsroot_name = "xfsroot.";
/*
* Convert IRIX API components into Linux/XFS API components,
* and vice-versa.
*/
static int
api_convert(char *name, const char *irixname, int irixflags, int compat)
{
if (strlen(irixname) >= MAXNAMELEN) {
errno = EINVAL;
return -1;
}
if (irixflags & ATTR_ROOT) {
if (compat)
strcpy(name, xfsroot_name);
else
strcpy(name, trusted_name);
} else if (irixflags & ATTR_SECURE) {
strcpy(name, secure_name);
} else {
strcpy(name, user_name);
}
strcat(name, irixname);
return 0;
}
static int
api_unconvert(char *name, const char *linuxname, int irixflags)
{
int type, length;
length = strlen(user_name);
if (strncmp(linuxname, user_name, length) == 0) {
type = 0; /*ATTR_USER*/
goto found;
}
length = strlen(secure_name);
if (strncmp(linuxname, secure_name, length) == 0) {
type = ATTR_SECURE;
goto found;
}
length = strlen(trusted_name);
if (strncmp(linuxname, trusted_name, length) == 0) {
type = ATTR_ROOT;
goto found;
}
length = strlen(xfsroot_name);
if (strncmp(linuxname, xfsroot_name, length) == 0) {
type = ATTR_ROOT;
goto found;
}
return 1;
found:
if ((irixflags & ATTR_SECURE) != 0 && (type != ATTR_SECURE))
return 1;
if ((irixflags & ATTR_ROOT) != 0 && (type != ATTR_ROOT))
return 1;
strcpy(name, linuxname + length);
return 0;
}
int
attr_get(const char *path, const char *attrname, char *attrvalue,
int *valuelength, int flags)
{
ssize_t (*get)(const char *, const char *, void *, size_t) =
flags & ATTR_DONTFOLLOW ? lgetxattr : getxattr;
int c, compat;
char name[MAXNAMELEN+16];
for (compat = 0; compat < 2; compat++) {
if ((c = api_convert(name, attrname, flags, compat)) < 0)
return c;
c = get(path, name, attrvalue, *valuelength);
if (c < 0 && (errno == ENOATTR || errno == ENOTSUP))
continue;
break;
}
if (c < 0 && errno == ERANGE) {
int size = get(path, name, NULL, 0);
if (size >= 0) {
*valuelength = size;
errno = E2BIG;
}
return c;
}
if (c < 0)
return c;
*valuelength = c;
return 0;
}
int
attr_getf(int fd, const char *attrname, char *attrvalue,
int *valuelength, int flags)
{
int c, compat;
char name[MAXNAMELEN+16];
for (compat = 0; compat < 2; compat++) {
if ((c = api_convert(name, attrname, flags, compat)) < 0)
return c;
c = fgetxattr(fd, name, attrvalue, *valuelength);
if (c < 0 && (errno == ENOATTR || errno == ENOTSUP))
continue;
break;
}
if (c < 0 && errno == ERANGE) {
int size = fgetxattr(fd, name, NULL, 0);
if (size >= 0) {
*valuelength = size;
errno = E2BIG;
}
return c;
}
if (c < 0)
return c;
*valuelength = c;
return 0;
}
int
attr_set(const char *path, const char *attrname, const char *attrvalue,
const int valuelength, int flags)
{
int c, compat, lflags = 0;
char name[MAXNAMELEN+16];
void *buffer = (void *)attrvalue;
if (flags & ATTR_CREATE)
lflags = XATTR_CREATE;
else if (flags & ATTR_REPLACE)
lflags = XATTR_REPLACE;
for (compat = 0; compat < 2; compat++) {
if ((c = api_convert(name, attrname, flags, compat)) < 0)
return c;
if (flags & ATTR_DONTFOLLOW)
c = lsetxattr(path, name, buffer, valuelength, lflags);
else
c = setxattr(path, name, buffer, valuelength, lflags);
if (c < 0 && (errno == ENOATTR || errno == ENOTSUP))
continue;
break;
}
return c;
}
int
attr_setf(int fd, const char *attrname,
const char *attrvalue, const int valuelength, int flags)
{
int c, compat, lflags = 0;
char name[MAXNAMELEN+16];
void *buffer = (void *)attrvalue;
if (flags & ATTR_CREATE)
lflags = XATTR_CREATE;
else if (flags & ATTR_REPLACE)
lflags = XATTR_REPLACE;
for (compat = 0; compat < 2; compat++) {
if ((c = api_convert(name, attrname, flags, compat)) < 0)
return c;
c = fsetxattr(fd, name, buffer, valuelength, lflags);
if (c < 0 && (errno == ENOATTR || errno == ENOTSUP))
continue;
break;
}
return c;
}
int
attr_remove(const char *path, const char *attrname, int flags)
{
int c, compat;
char name[MAXNAMELEN+16];
for (compat = 0; compat < 2; compat++) {
if ((c = api_convert(name, attrname, flags, compat)) < 0)
return c;
if (flags & ATTR_DONTFOLLOW)
c = lremovexattr(path, name);
else
c = removexattr(path, name);
if (c < 0 && (errno == ENOATTR || errno == ENOTSUP))
continue;
break;
}
return c;
}
int
attr_removef(int fd, const char *attrname, int flags)
{
int c, compat;
char name[MAXNAMELEN+16];
for (compat = 0; compat < 2; compat++) {
if ((c = api_convert(name, attrname, flags, compat)) < 0)
return c;
c = fremovexattr(fd, name);
if (c < 0 && (errno == ENOATTR || errno == ENOTSUP))
continue;
break;
}
return c;
}
/*
* Helper routine for attr_list functions.
*/
static int
attr_list_pack(const char *name, const int valuelen,
char *buffer, const int buffersize,
int *start_offset, int *end_offset)
{
attrlist_ent_t *aentp;
attrlist_t *alist = (attrlist_t *)buffer;
int size = roundup(strlen(name) + 1 + sizeof(aentp->a_valuelen), 8);
if ((*end_offset - size) < (*start_offset + sizeof(alist->al_count))) {
alist->al_more = 1;
return 1;
}
*end_offset -= size;
aentp = (attrlist_ent_t *)&buffer[ *end_offset ];
aentp->a_valuelen = valuelen;
strncpy(aentp->a_name, name, size - sizeof(aentp->a_valuelen));
*start_offset += sizeof(alist->al_offset);
alist->al_offset[alist->al_count] = *end_offset;
alist->al_count++;
return 0;
}
int
attr_list(const char *path, char *buffer, const int buffersize, int flags,
attrlist_cursor_t *cursor)
{
const char *l;
int length, vlength, count = 0;
char lbuf[MAXLISTLEN+1];
char name[MAXNAMELEN+16];
int start_offset, end_offset;
if (buffersize < sizeof(attrlist_t)) {
errno = EINVAL;
return -1;
}
memset(buffer, 0, sizeof(attrlist_t));
if (flags & ATTR_DONTFOLLOW)
length = llistxattr(path, lbuf, sizeof(lbuf) - 1);
else
length = listxattr(path, lbuf, sizeof(lbuf) - 1);
if (length <= 0)
return length;
lbuf[length] = 0; /* not supposed to be necessary */
start_offset = sizeof(attrlist_t);
end_offset = buffersize & ~(8-1); /* 8 byte align */
for (l = lbuf; l != lbuf + length; l = strchr(l, '\0') + 1) {
if (api_unconvert(name, l, flags))
continue;
if (flags & ATTR_DONTFOLLOW)
vlength = lgetxattr(path, l, NULL, 0);
else
vlength = getxattr(path, l, NULL, 0);
if (vlength < 0 && (errno == ENOATTR || errno == ENOTSUP))
continue;
if (count++ < cursor->opaque[0])
continue;
if (attr_list_pack(name, vlength, buffer, buffersize,
&start_offset, &end_offset)) {
if (cursor->opaque[0] == count - 1) {
errno = EINVAL;
return -1;
}
cursor->opaque[0] = count - 1;
break;
}
}
return 0;
}
int
attr_listf(int fd, char *buffer, const int buffersize, int flags,
attrlist_cursor_t *cursor)
{
const char *l;
int length, vlength, count = 0;
char lbuf[MAXLISTLEN+1];
char name[MAXNAMELEN+16];
int start_offset, end_offset;
if (buffersize < sizeof(attrlist_t)) {
errno = EINVAL;
return -1;
}
memset(buffer, 0, sizeof(attrlist_t));
length = flistxattr(fd, lbuf, sizeof(lbuf) - 1);
if (length < 0)
return length;
lbuf[length] = 0; /* not supposed to be necessary */
start_offset = sizeof(attrlist_t);
end_offset = buffersize & ~(8-1); /* 8 byte align */
for (l = lbuf; l != lbuf + length; l = strchr(l, '\0') + 1) {
if (api_unconvert(name, l, flags))
continue;
vlength = fgetxattr(fd, l, NULL, 0);
if (vlength < 0 && (errno == ENOATTR || errno == ENOTSUP))
continue;
if (count++ < cursor->opaque[0])
continue;
if (attr_list_pack(name, vlength, buffer, buffersize,
&start_offset, &end_offset)) {
if (cursor->opaque[0] == count - 1) {
errno = EINVAL;
return -1;
}
cursor->opaque[0] = count - 1;
break;
}
}
return 0;
}
/*
* Helper routines for the attr_multi functions. In IRIX, the
* multi routines are a single syscall - in Linux, we break em
* apart in userspace and make individual syscalls for each.
*/
#pragma GCC diagnostic ignored "-Wdeprecated-declarations"
static int
attr_single(const char *path, attr_multiop_t *op, int flags)
{
int r = -1;
errno = EINVAL;
flags |= op->am_flags;
if (op->am_opcode == ATTR_OP_GET)
r = attr_get(path, op->am_attrname, op->am_attrvalue,
&op->am_length, flags);
else if (op->am_opcode == ATTR_OP_SET)
r = attr_set(path, op->am_attrname, op->am_attrvalue,
op->am_length, flags);
else if (op->am_opcode == ATTR_OP_REMOVE)
r = attr_remove(path, op->am_attrname, flags);
return r;
}
static int
attr_singlef(const int fd, attr_multiop_t *op, int flags)
{
int r = -1;
errno = EINVAL;
flags |= op->am_flags;
if (op->am_opcode == ATTR_OP_GET)
r = attr_getf(fd, op->am_attrname, op->am_attrvalue,
&op->am_length, flags);
else if (op->am_opcode == ATTR_OP_SET)
r = attr_setf(fd, op->am_attrname, op->am_attrvalue,
op->am_length, flags);
else if (op->am_opcode == ATTR_OP_REMOVE)
r = attr_removef(fd, op->am_attrname, flags);
return r;
}
#pragma GCC diagnostic warning "-Wdeprecated-declarations"
/*
* Operate on multiple attributes of the same object simultaneously
*
* From the manpage: "attr_multi will fail if ... a bit other than
* ATTR_DONTFOLLOW was set in the flag argument." flags must be
* checked here as they are not passed into the kernel.
*/
int
attr_multi(const char *path, attr_multiop_t *multiops, int count, int flags)
{
int i, tmp, r = -1;
errno = EINVAL;
if ((flags & ATTR_DONTFOLLOW) != flags)
return r;
r = errno = 0;
for (i = 0; i < count; i++) {
tmp = attr_single(path, &multiops[i], flags);
if (tmp) r = tmp;
}
return r;
}
int
attr_multif(int fd, attr_multiop_t *multiops, int count, int flags)
{
int i, tmp, r = -1;
errno = EINVAL;
if ((flags & ATTR_DONTFOLLOW) != flags)
return r;
r = errno = 0;
for (i = 0; i < count; i++) {
tmp = attr_singlef(fd, &multiops[i], flags);
if (tmp) r = tmp;
}
return r;
}