[dump.git] / restore / xattr.c

/*
 * Copyright (c) 1999-2004
 *	Stelian Pop <stelian@popies.net>, 1999-2004
 *
 * 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. Neither the name of the University 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 REGENTS 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 REGENTS 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.
 */

#ifndef lint
static const char rcsid[] =
	"$Id: xattr.c,v 1.2 2005/06/08 09:34:40 stelian Exp $";
#endif /* not lint */

#include <config.h>
#include <compatlfs.h>
#include <compaterr.h>
#include <sys/types.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <errno.h>
#include <bsdcompat.h>
#include <protocols/dumprestore.h>
#include "restore.h"
#include "extern.h"
#include "pathnames.h"

/*
 * Data structures below taken from the kernel
 */

/* Maximum number of references to one attribute block */
#define EXT2_XATTR_REFCOUNT_MAX		1024

/* Name indexes */
#define EXT2_XATTR_INDEX_MAX			10
#define EXT2_XATTR_INDEX_USER			1
#define EXT2_XATTR_INDEX_POSIX_ACL_ACCESS	2
#define EXT2_XATTR_INDEX_POSIX_ACL_DEFAULT	3
#define EXT2_XATTR_INDEX_TRUSTED		4
#define	EXT2_XATTR_INDEX_LUSTRE			5
#define EXT2_XATTR_INDEX_SECURITY	        6

struct ext2_xattr_header {
	u_int32_t	h_magic;	/* magic number for identification */
	u_int32_t	h_refcount;	/* reference count */
	u_int32_t	h_blocks;	/* number of disk blocks used */
	u_int32_t	h_hash;		/* hash value of all attributes */
	u_int32_t	h_reserved[4];	/* zero right now */
};

struct ext3_xattr_ibody_header {
	u_int32_t	h_magic;	/* magic number for identification */
};

struct ext2_xattr_entry {
	u_char		e_name_len;	/* length of name */
	u_char		e_name_index;	/* attribute name index */
	u_int16_t	e_value_offs;	/* offset in disk block of value */
	u_int32_t	e_value_block;	/* disk block attribute is stored on (n/i) */
	u_int32_t	e_value_size;	/* size of attribute value */
	u_int32_t	e_hash;		/* hash value of name and value */
	char		e_name[0];	/* attribute name */
};

#define EXT2_XATTR_PAD_BITS		2
#define EXT2_XATTR_PAD		(1<<EXT2_XATTR_PAD_BITS)
#define EXT2_XATTR_ROUND		(EXT2_XATTR_PAD-1)
#define EXT2_XATTR_LEN(name_len) \
	(((name_len) + EXT2_XATTR_ROUND + \
	sizeof(struct ext2_xattr_entry)) & ~EXT2_XATTR_ROUND)
#define EXT2_XATTR_NEXT(entry) \
	( (struct ext2_xattr_entry *)( \
	  (char *)(entry) + EXT2_XATTR_LEN((entry)->e_name_len)) )
#define EXT3_XATTR_SIZE(size) \
	(((size) + EXT2_XATTR_ROUND) & ~EXT2_XATTR_ROUND)

#define HDR(buffer) ((struct ext2_xattr_header *)(buffer))
#define ENTRY(ptr) ((struct ext2_xattr_entry *)(ptr))
#define IS_LAST_ENTRY(entry) (*(__u32 *)(entry) == 0)

#define BFIRST(buffer) ENTRY(HDR(buffer)+1)
#define IFIRST(buffer) ENTRY(((struct ext3_xattr_ibody_header *)(buffer))+1)

#define FIRST_ENTRY(buffer) \
	((HDR(buffer)->h_magic == EXT2_XATTR_MAGIC2) ? \
		IFIRST(buffer) : \
		BFIRST(buffer))

/*
 * On-block xattr value offsets start at the beginning of the block, but
 * on-inode xattr value offsets start after the initial header 
 * (ext3_xattr_ibody_header).
 */
#define VALUE_OFFSET(buffer, entry) \
	(((HDR(buffer)->h_magic == EXT2_XATTR_MAGIC2) ? \
		(entry)->e_value_offs + sizeof(struct ext3_xattr_ibody_header) : \
		(entry)->e_value_offs))
	
/*
 * xattr syscalls do not exist yet in libc, get our own copy here,
 * taken from libattr.
 */
#if defined (__i386__)
# define HAVE_XATTR_SYSCALLS 1
# define __NR_lsetxattr		227
# define __NR_lgetxattr		230
# define __NR_llistxattr	233
#elif defined (__sparc__)
# define HAVE_XATTR_SYSCALLS 1
# define __NR_lsetxattr		170
# define __NR_lgetxattr		173
# define __NR_llistxattr	179
#elif defined (__ia64__)
# define HAVE_XATTR_SYSCALLS 1
# define __NR_lsetxattr		1218
# define __NR_lgetxattr		1221
# define __NR_llistxattr	1224
#elif defined (__powerpc__)
# define HAVE_XATTR_SYSCALLS 1
# define __NR_lsetxattr		210
# define __NR_lgetxattr		213
# define __NR_llistxattr	216
#elif defined (__x86_64__)
# define HAVE_XATTR_SYSCALLS 1
# define __NR_lsetxattr		189
# define __NR_lgetxattr		192
# define __NR_llistxattr	195
#elif defined (__s390__)
# define HAVE_XATTR_SYSCALLS 1
# define __NR_lsetxattr		225
# define __NR_lgetxattr		228
# define __NR_llistxattr	231
#elif defined (__arm__)
# define HAVE_XATTR_SYSCALLS 1
# define __NR_SYSCALL_BASE 0x900000
# define __NR_lsetxattr		(__NR_SYSCALL_BASE+227)
# define __NR_lgetxattr		(__NR_SYSCALL_BASE+230)
# define __NR_llistxattr	(__NR_SYSCALL_BASE+233)
#elif defined (__mips64__)
# define HAVE_XATTR_SYSCALLS 1
# define __NR_Linux 5000
# define __NR_lsetxattr		(__NR_Linux + 218)
# define __NR_lgetxattr		(__NR_Linux + 221)
# define __NR_llistxattr	(__NR_Linux + 224)
#elif defined (__mips__)
# define HAVE_XATTR_SYSCALLS 1
# define __NR_Linux 4000
# define __NR_lsetxattr		(__NR_Linux + 225)
# define __NR_lgetxattr		(__NR_Linux + 228)
# define __NR_llistxattr	(__NR_Linux + 231)
#elif defined (__alpha__)
# define HAVE_XATTR_SYSCALLS 1
# define __NR_lsetxattr		383
# define __NR_lgetxattr		386
# define __NR_llistxattr	389
#elif defined (__mc68000__)
# define HAVE_XATTR_SYSCALLS 1
# define __NR_lsetxattr		224
# define __NR_lgetxattr		227
# define __NR_llistxattr	230
#else
# warning "Extended attribute syscalls undefined for this architecture"
# define HAVE_XATTR_SYSCALLS 0
#endif

#if HAVE_XATTR_SYSCALLS
# define SYSCALL(args...)	syscall(args)
#else
# define SYSCALL(args...)	( errno = ENOSYS, -1 )
#endif

static int lsetxattr __P((const char *, const char *, void *, size_t, int));
static ssize_t lgetxattr __P((const char *, const char *, void *, size_t));
static ssize_t llistxattr __P((const char *, char *, size_t));
static int xattr_cb_list __P((char *, char *, int, void *));
static int xattr_cb_set __P((char *, char *, int, void *));
static int xattr_cb_compare __P((char *, char *, int, void *));
static int xattr_verify __P((char *));
static int xattr_count __P((char *, int *));
static int xattr_walk __P((char *, int (*)(char *, char *, int, void *), void *));

static int
lsetxattr(const char *path, const char *name, void *value, size_t size, int flags)
{
	return SYSCALL(__NR_lsetxattr, path, name, value, size, flags);
}

static ssize_t
lgetxattr(const char *path, const char *name, void *value, size_t size)
{
	return SYSCALL(__NR_lgetxattr, path, name, value, size);
}

static ssize_t
llistxattr(const char *path, char *list, size_t size)
{
	return SYSCALL(__NR_llistxattr, path, list, size);
}

#define POSIX_ACL_XATTR_VERSION 0x0002

#define ACL_UNDEFINED_ID        (-1)

#define ACL_USER_OBJ            (0x01)
#define ACL_USER                (0x02)
#define ACL_GROUP_OBJ           (0x04)
#define ACL_GROUP               (0x08)
#define ACL_MASK                (0x10)
#define ACL_OTHER               (0x20)

typedef struct {
	u_int16_t	e_tag;
	u_int16_t	e_perm;
	u_int32_t	e_id;
} posix_acl_xattr_entry;

typedef struct {
	u_int32_t		a_version;
	posix_acl_xattr_entry	a_entries[0];
} posix_acl_xattr_header;

static inline size_t
posix_acl_xattr_size(int count)
{
	return (sizeof(posix_acl_xattr_header) +
		(count * sizeof(posix_acl_xattr_entry)));
}

struct posix_acl_entry {
	short		e_tag;
	unsigned short	e_perm;
	unsigned int	e_id;
};

struct posix_acl {
	unsigned int		a_count;
	struct posix_acl_entry	a_entries[0];
};

#define EXT3_ACL_VERSION        0x0001

typedef struct {
	u_int16_t	e_tag;
	u_int16_t	e_perm;
	u_int32_t	e_id;
} ext3_acl_entry;

typedef struct {
	u_int16_t	e_tag;
	u_int16_t	e_perm;
} ext3_acl_entry_short;

typedef struct {
	u_int32_t	a_version;
} ext3_acl_header;

static inline int ext3_acl_count(size_t size)
{
	ssize_t s;
	size -= sizeof(ext3_acl_header);
	s = size - 4 * sizeof(ext3_acl_entry_short);
	if (s < 0) {
		if (size % sizeof(ext3_acl_entry_short))
			return -1;
		return size / sizeof(ext3_acl_entry_short);
	} else {
		if (s % sizeof(ext3_acl_entry))
			return -1;
		return s / sizeof(ext3_acl_entry) + 4;
	}
}

int
posix_acl_to_xattr(const struct posix_acl *acl, void *buffer, size_t size) {
	posix_acl_xattr_header *ext_acl = (posix_acl_xattr_header *)buffer;
	posix_acl_xattr_entry *ext_entry = ext_acl->a_entries;
	int real_size, n;

	real_size = posix_acl_xattr_size(acl->a_count);
	if (!buffer)
		return real_size;
	if (real_size > size) {
		fprintf(stderr, "ACL: not enough space to convert (%d %d)\n", real_size, size);
		return -1;
	}

	ext_acl->a_version = POSIX_ACL_XATTR_VERSION;
	if (Bcvt) 
		swabst("1i", (u_char *)ext_acl);

	for (n=0; n < acl->a_count; n++, ext_entry++) {
		ext_entry->e_tag  = acl->a_entries[n].e_tag;
		ext_entry->e_perm = acl->a_entries[n].e_perm;
		ext_entry->e_id   = acl->a_entries[n].e_id;
		if (Bcvt)
			swabst("2s1i", (u_char *)ext_entry);
	}
	return real_size;
}

static struct posix_acl *
ext3_acl_from_disk(const void *value, size_t size)
{
	const char *end = (char *)value + size;
	int n, count;
	struct posix_acl *acl;

	if (!value)
		return NULL;
	if (size < sizeof(ext3_acl_header)) {
		fprintf(stderr, "ACL size too little\n");
		return NULL;
	}
	if (Bcvt) 
		swabst("1i", (u_char *)value);
	if (((ext3_acl_header *)value)->a_version != EXT3_ACL_VERSION) {
		fprintf(stderr, "ACL version unknown\n");
		return NULL;
	}
	value = (char *)value + sizeof(ext3_acl_header);
	count = ext3_acl_count(size);
	if (count < 0) {
		fprintf(stderr, "ACL bad count\n");
		return NULL;
	}
	if (count == 0)
		return NULL;
	acl = malloc(sizeof(struct posix_acl) + count * sizeof(struct posix_acl_entry));
	if (!acl) {
		fprintf(stderr, "ACL malloc failed\n");
		return NULL;
	}
	acl->a_count = count;

	for (n=0; n < count; n++) {
		if (Bcvt)
			swabst("2s1i", (u_char *)value);
		ext3_acl_entry *entry = (ext3_acl_entry *)value;
		if ((char *)value + sizeof(ext3_acl_entry_short) > end)
			goto fail;
		acl->a_entries[n].e_tag  = entry->e_tag;
		acl->a_entries[n].e_perm = entry->e_perm;
		switch(acl->a_entries[n].e_tag) {
		case ACL_USER_OBJ:
		case ACL_GROUP_OBJ:
		case ACL_MASK:
		case ACL_OTHER:
			value = (char *)value + sizeof(ext3_acl_entry_short);
			acl->a_entries[n].e_id = ACL_UNDEFINED_ID;
			break;

		case ACL_USER:
		case ACL_GROUP:
			value = (char *)value + sizeof(ext3_acl_entry);
			if ((char *)value > end)
				goto fail;
			acl->a_entries[n].e_id = entry->e_id;
			break;

		default:
			goto fail;
		}
	}
	if (value != end)
		goto fail;
	return acl;

fail:
	fprintf(stderr, "ACL bad entry\n");
	free(acl);
	return NULL;
}

/*
 * Dump code starts here :)
 */

static int
xattr_cb_list(char *name, char *value, int valuelen, void *private)
{
	value[valuelen] = '\0';
	printf("EA: %s:%s\n", name, value);

	return GOOD;
}

static int
xattr_cb_set(char *name, char *value, int valuelen, void *private)
{
	char *path = (char *)private;

	if (lsetxattr(path, name, value, valuelen, 0) < 0) {
		warn("lsetxattr %s failed", path);
		return FAIL;
	}
	return GOOD;
}

static int
xattr_cb_compare(char *name, char *value, int valuelen, void *private)
{
	char *path = (char *)private;
	char valuef[XATTR_MAXSIZE];
	int valuesz;

	valuesz = lgetxattr(path, name, valuef, XATTR_MAXSIZE);
	if (valuesz < 0) {
		warn("%s: lgetxattr failed\n", path);
		return FAIL;
	}

	if (valuesz != valuelen) {
		fprintf(stderr, "%s: EA %s value changed\n", path, value);
		return FAIL;
	}

	if (memcmp(value, valuef, valuelen)) {
		fprintf(stderr, "%s: EA %s value changed\n", path, value);
		return FAIL;
	}

	return GOOD;
}

static int
xattr_verify(char *buffer)
{
	struct ext2_xattr_entry *entry;
	char *end;

	end = buffer + XATTR_MAXSIZE;

	if (Bcvt)
		swabst("4i", (u_char *)buffer);

	if (HDR(buffer)->h_magic != EXT2_XATTR_MAGIC &&
	    HDR(buffer)->h_magic != EXT2_XATTR_MAGIC2) {
		fprintf(stderr, "error in EA block 1\n");
		fprintf(stderr, "magic = %x\n", HDR(buffer)->h_magic);
		
		return FAIL;
	}

	/* check the on-disk data structure */
	entry = FIRST_ENTRY(buffer);
	if (Bcvt) 
		swabst("2b1s3i", (u_char *)entry);
	while (!IS_LAST_ENTRY(entry)) {
		struct ext2_xattr_entry *next = EXT2_XATTR_NEXT(entry);

		if ((char *)next >= end) {
			fprintf(stderr, "error in EA block\n");
			return FAIL;
		}
		entry = next;
		if (Bcvt) 
			swabst("2b1s3i", (u_char *)entry);
	}
	return GOOD;
}

static int
xattr_count(char *buffer, int *count)
{
	struct ext2_xattr_entry *entry;
	int result = 0;

	/* list the attribute names */
	for (entry = FIRST_ENTRY(buffer); !IS_LAST_ENTRY(entry);
	     entry = EXT2_XATTR_NEXT(entry))
		result++;

	*count = result;
	return GOOD;
}

static int
xattr_walk(char *buffer, int (*xattr_cb)(char *, char *, int, void *), void *private)
{
	struct ext2_xattr_entry *entry;

	/* list the attribute names */
	for (entry = FIRST_ENTRY(buffer); !IS_LAST_ENTRY(entry);
	     entry = EXT2_XATTR_NEXT(entry)) {
	     	char name[XATTR_MAXSIZE], value[XATTR_MAXSIZE];
		int off;
		int convertacl = 0;

		switch (entry->e_name_index) {
		case EXT2_XATTR_INDEX_USER:
			strcpy(name, "user.");
			break;
		case EXT2_XATTR_INDEX_POSIX_ACL_ACCESS:
			strcpy(name, "system.posix_acl_access");
			convertacl = 1;
			break;
		case EXT2_XATTR_INDEX_POSIX_ACL_DEFAULT:
			strcpy(name, "system.posix_acl_default");
			convertacl = 1;
			break;
		case EXT2_XATTR_INDEX_TRUSTED:
			strcpy(name, "trusted.");
			break;
		case EXT2_XATTR_INDEX_LUSTRE:
			strcpy(name, "lustre.");
			break;
		case EXT2_XATTR_INDEX_SECURITY:
			strcpy(name, "security.");
			break;
		default:
			fprintf(stderr, "Unknown EA index\n");
			return FAIL;
		}

		off = strlen(name);
		memcpy(name + off, entry->e_name, entry->e_name_len);
		name[off + entry->e_name_len] = '\0';

		memcpy(value, buffer + VALUE_OFFSET(buffer, entry), entry->e_value_size);

		if (convertacl) {
			struct posix_acl *acl;
			int size;

			acl = ext3_acl_from_disk(value, entry->e_value_size);
			if (!acl)
				return FAIL;
			size = posix_acl_to_xattr(acl, value, XATTR_MAXSIZE);
			if (size < 0)
				return FAIL;
			entry->e_value_size = size;
			free(acl);
		}

		if (xattr_cb(name, value, entry->e_value_size, private) != GOOD)
			return FAIL;
	}

	return GOOD;
}

int
xattr_compare(char *path, char *buffer)
{
	int countf, countt;
	char *names = NULL, *end_names, *name;

	countf = llistxattr(path, NULL, 0);
	if (countf < 0) {
		warn("%s: llistxattr failed", path);
		return FAIL;
	}

	names = malloc(countf + 1);
	if (!names) {
		warn("%s: llistxattr failed", path);
		return FAIL;
	}

	countf = llistxattr(path, names, countf);
	if (countf < 0) {
		warn("%s: llistxattr failed", path);
		free(names);
		return FAIL;
	}

	names[countf] = '\0';
	end_names = names + countf;

	countf = 0;
	for (name = names; name != end_names; name = strchr(name, '\0') + 1) {
		if (!*name)
			continue;
		countf++;
	}

	free(names);

	if (buffer) {
		if (xattr_verify(buffer) == FAIL)
			return FAIL;

		if (xattr_count(buffer, &countt) == FAIL)
			return FAIL;
	}
	else
		countt = 0;

	if (countf != countt) {
		fprintf(stderr, "%s: EA count changed from %d to %d\n", path, countt, countf);
		return FAIL;
	}

	if (!buffer)
		return GOOD;

	return xattr_walk(buffer, xattr_cb_compare, path);
}

int
xattr_extract(char *path, char *buffer)
{
	if (dflag) {
		fprintf(stderr, "xattr_extract(%s)\n", path);
		xattr_walk(buffer, xattr_cb_list, NULL);
	}

	if (xattr_verify(buffer) == FAIL)
		return FAIL;

	return xattr_walk(buffer, xattr_cb_set, path);
}
Commit	Line	Data
cca7148b SP	1	/*
	2	* Copyright (c) 1999-2004
	3	* Stelian Pop <stelian@popies.net>, 1999-2004
	4	*
	5	* Redistribution and use in source and binary forms, with or without
	6	* modification, are permitted provided that the following conditions
	7	* are met:
	8	* 1. Redistributions of source code must retain the above copyright
	9	* notice, this list of conditions and the following disclaimer.
	10	* 2. Redistributions in binary form must reproduce the above copyright
	11	* notice, this list of conditions and the following disclaimer in the
	12	* documentation and/or other materials provided with the distribution.
	13	* 3. Neither the name of the University nor the names of its contributors
	14	* may be used to endorse or promote products derived from this software
	15	* without specific prior written permission.
	16	*
	17	* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
	18	* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	19	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	20	* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
	21	* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
	22	* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
	23	* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
	24	* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
	25	* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
	26	* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
	27	* SUCH DAMAGE.
	28	*/
	29
	30	#ifndef lint
	31	static const char rcsid[] =
b630baf0	32	"$Id: xattr.c,v 1.2 2005/06/08 09:34:40 stelian Exp $";
cca7148b SP	33	#endif /* not lint */
	34
	35	#include <config.h>
	36	#include <compatlfs.h>
	37	#include <compaterr.h>
	38	#include <sys/types.h>
	39	#include <stdio.h>
	40	#include <stdlib.h>
	41	#include <string.h>
	42	#include <unistd.h>
	43	#include <errno.h>
	44	#include <bsdcompat.h>
	45	#include <protocols/dumprestore.h>
	46	#include "restore.h"
	47	#include "extern.h"
	48	#include "pathnames.h"
	49
	50	/*
	51	* Data structures below taken from the kernel
	52	*/
	53
	54	/* Maximum number of references to one attribute block */
	55	#define EXT2_XATTR_REFCOUNT_MAX 1024
	56
	57	/* Name indexes */
	58	#define EXT2_XATTR_INDEX_MAX 10
	59	#define EXT2_XATTR_INDEX_USER 1
	60	#define EXT2_XATTR_INDEX_POSIX_ACL_ACCESS 2
	61	#define EXT2_XATTR_INDEX_POSIX_ACL_DEFAULT 3
	62	#define EXT2_XATTR_INDEX_TRUSTED 4
	63	#define EXT2_XATTR_INDEX_LUSTRE 5
	64	#define EXT2_XATTR_INDEX_SECURITY 6
	65
	66	struct ext2_xattr_header {
	67	u_int32_t h_magic; /* magic number for identification */
	68	u_int32_t h_refcount; /* reference count */
	69	u_int32_t h_blocks; /* number of disk blocks used */
	70	u_int32_t h_hash; /* hash value of all attributes */
	71	u_int32_t h_reserved[4]; /* zero right now */
	72	};
	73
	74	struct ext3_xattr_ibody_header {
	75	u_int32_t h_magic; /* magic number for identification */
	76	};
	77
	78	struct ext2_xattr_entry {
	79	u_char e_name_len; /* length of name */
	80	u_char e_name_index; /* attribute name index */
	81	u_int16_t e_value_offs; /* offset in disk block of value */
	82	u_int32_t e_value_block; /* disk block attribute is stored on (n/i) */
	83	u_int32_t e_value_size; /* size of attribute value */
	84	u_int32_t e_hash; /* hash value of name and value */
	85	char e_name[0]; /* attribute name */
	86	};
	87
	88	#define EXT2_XATTR_PAD_BITS 2
	89	#define EXT2_XATTR_PAD (1<<EXT2_XATTR_PAD_BITS)
	90	#define EXT2_XATTR_ROUND (EXT2_XATTR_PAD-1)
	91	#define EXT2_XATTR_LEN(name_len) \
	92	(((name_len) + EXT2_XATTR_ROUND + \
	93	sizeof(struct ext2_xattr_entry)) & ~EXT2_XATTR_ROUND)
	94	#define EXT2_XATTR_NEXT(entry) \
	95	( (struct ext2_xattr_entry *)( \
	96	(char *)(entry) + EXT2_XATTR_LEN((entry)->e_name_len)) )
97	#define EXT3_XATTR_SIZE(size) \
98	(((size) + EXT2_XATTR_ROUND) & ~EXT2_XATTR_ROUND)
99
100	#define HDR(buffer) ((struct ext2_xattr_header *)(buffer))
101	#define ENTRY(ptr) ((struct ext2_xattr_entry *)(ptr))
102	#define IS_LAST_ENTRY(entry) ((__u32 )(entry) == 0)
103
104	#define BFIRST(buffer) ENTRY(HDR(buffer)+1)
105	#define IFIRST(buffer) ENTRY(((struct ext3_xattr_ibody_header *)(buffer))+1)
106
107	#define FIRST_ENTRY(buffer) \
108	((HDR(buffer)->h_magic == EXT2_XATTR_MAGIC2) ? \
109	IFIRST(buffer) : \
110	BFIRST(buffer))
111
112	/*
113	* On-block xattr value offsets start at the beginning of the block, but
114	* on-inode xattr value offsets start after the initial header
115	* (ext3_xattr_ibody_header).
116	*/
117	#define VALUE_OFFSET(buffer, entry) \
118	(((HDR(buffer)->h_magic == EXT2_XATTR_MAGIC2) ? \
119	(entry)->e_value_offs + sizeof(struct ext3_xattr_ibody_header) : \
120	(entry)->e_value_offs))
121
122	/*
123	* xattr syscalls do not exist yet in libc, get our own copy here,
124	* taken from libattr.
125	*/
126	#if defined (__i386__)
127	# define HAVE_XATTR_SYSCALLS 1
128	# define __NR_lsetxattr 227
129	# define __NR_lgetxattr 230
130	# define __NR_llistxattr 233
131	#elif defined (__sparc__)
132	# define HAVE_XATTR_SYSCALLS 1
133	# define __NR_lsetxattr 170
134	# define __NR_lgetxattr 173
135	# define __NR_llistxattr 179
136	#elif defined (__ia64__)
137	# define HAVE_XATTR_SYSCALLS 1
138	# define __NR_lsetxattr 1218
139	# define __NR_lgetxattr 1221
140	# define __NR_llistxattr 1224
141	#elif defined (__powerpc__)
142	# define HAVE_XATTR_SYSCALLS 1
143	# define __NR_lsetxattr 210
144	# define __NR_lgetxattr 213
145	# define __NR_llistxattr 216
146	#elif defined (__x86_64__)
147	# define HAVE_XATTR_SYSCALLS 1
148	# define __NR_lsetxattr 189
149	# define __NR_lgetxattr 192
150	# define __NR_llistxattr 195
151	#elif defined (__s390__)
152	# define HAVE_XATTR_SYSCALLS 1
153	# define __NR_lsetxattr 225
154	# define __NR_lgetxattr 228
155	# define __NR_llistxattr 231
156	#elif defined (__arm__)
157	# define HAVE_XATTR_SYSCALLS 1
158	# define __NR_SYSCALL_BASE 0x900000
159	# define __NR_lsetxattr (__NR_SYSCALL_BASE+227)
160	# define __NR_lgetxattr (__NR_SYSCALL_BASE+230)
161	# define __NR_llistxattr (__NR_SYSCALL_BASE+233)
162	#elif defined (__mips64__)
163	# define HAVE_XATTR_SYSCALLS 1
164	# define __NR_Linux 5000
165	# define __NR_lsetxattr (__NR_Linux + 218)
166	# define __NR_lgetxattr (__NR_Linux + 221)
167	# define __NR_llistxattr (__NR_Linux + 224)
168	#elif defined (__mips__)
169	# define HAVE_XATTR_SYSCALLS 1
170	# define __NR_Linux 4000
171	# define __NR_lsetxattr (__NR_Linux + 225)
172	# define __NR_lgetxattr (__NR_Linux + 228)
173	# define __NR_llistxattr (__NR_Linux + 231)
174	#elif defined (__alpha__)
175	# define HAVE_XATTR_SYSCALLS 1
176	# define __NR_lsetxattr 383
177	# define __NR_lgetxattr 386
178	# define __NR_llistxattr 389
179	#elif defined (__mc68000__)
180	# define HAVE_XATTR_SYSCALLS 1
181	# define __NR_lsetxattr 224
182	# define __NR_lgetxattr 227
183	# define __NR_llistxattr 230
184	#else
185	# warning "Extended attribute syscalls undefined for this architecture"
186	# define HAVE_XATTR_SYSCALLS 0
187	#endif
188
189	#if HAVE_XATTR_SYSCALLS
190	# define SYSCALL(args...) syscall(args)
191	#else
192	# define SYSCALL(args...) ( errno = ENOSYS, -1 )
193	#endif
194
195	static int lsetxattr __P((const char , const char , void *, size_t, int));
196	static ssize_t lgetxattr __P((const char , const char , void *, size_t));
197	static ssize_t llistxattr __P((const char , char , size_t));
198	static int xattr_cb_list __P((char , char , int, void *));
199	static int xattr_cb_set __P((char , char , int, void *));
200	static int xattr_cb_compare __P((char , char , int, void *));
201	static int xattr_verify __P((char *));
202	static int xattr_count __P((char , int ));
203	static int xattr_walk __P((char , int ()(char , char , int, void ), void ));
204
205	static int
206	lsetxattr(const char path, const char name, void *value, size_t size, int flags)
207	{
208	return SYSCALL(__NR_lsetxattr, path, name, value, size, flags);
209	}
210
211	static ssize_t
212	lgetxattr(const char path, const char name, void *value, size_t size)
213	{
214	return SYSCALL(__NR_lgetxattr, path, name, value, size);
215	}
216
217	static ssize_t
218	llistxattr(const char path, char list, size_t size)
219	{
220	return SYSCALL(__NR_llistxattr, path, list, size);
221	}
222
b630baf0 SP	223	#define POSIX_ACL_XATTR_VERSION 0x0002
	224
	225	#define ACL_UNDEFINED_ID (-1)
	226
	227	#define ACL_USER_OBJ (0x01)
	228	#define ACL_USER (0x02)
	229	#define ACL_GROUP_OBJ (0x04)
	230	#define ACL_GROUP (0x08)
	231	#define ACL_MASK (0x10)
	232	#define ACL_OTHER (0x20)
	233
	234	typedef struct {
	235	u_int16_t e_tag;
	236	u_int16_t e_perm;
	237	u_int32_t e_id;
	238	} posix_acl_xattr_entry;
	239
	240	typedef struct {
	241	u_int32_t a_version;
	242	posix_acl_xattr_entry a_entries[0];
	243	} posix_acl_xattr_header;
	244
	245	static inline size_t
	246	posix_acl_xattr_size(int count)
	247	{
	248	return (sizeof(posix_acl_xattr_header) +
	249	(count * sizeof(posix_acl_xattr_entry)));
	250	}
	251
	252	struct posix_acl_entry {
	253	short e_tag;
	254	unsigned short e_perm;
	255	unsigned int e_id;
	256	};
	257
	258	struct posix_acl {
	259	unsigned int a_count;
	260	struct posix_acl_entry a_entries[0];
	261	};
	262
	263	#define EXT3_ACL_VERSION 0x0001
	264
	265	typedef struct {
	266	u_int16_t e_tag;
	267	u_int16_t e_perm;
	268	u_int32_t e_id;
	269	} ext3_acl_entry;
	270
	271	typedef struct {
	272	u_int16_t e_tag;
	273	u_int16_t e_perm;
	274	} ext3_acl_entry_short;
	275
	276	typedef struct {
	277	u_int32_t a_version;
	278	} ext3_acl_header;
	279
	280	static inline int ext3_acl_count(size_t size)
	281	{
	282	ssize_t s;
	283	size -= sizeof(ext3_acl_header);
	284	s = size - 4 * sizeof(ext3_acl_entry_short);
	285	if (s < 0) {
	286	if (size % sizeof(ext3_acl_entry_short))
287	return -1;
288	return size / sizeof(ext3_acl_entry_short);
289	} else {
290	if (s % sizeof(ext3_acl_entry))
291	return -1;
292	return s / sizeof(ext3_acl_entry) + 4;
293	}
294	}
295
296	int
297	posix_acl_to_xattr(const struct posix_acl acl, void buffer, size_t size) {
298	posix_acl_xattr_header ext_acl = (posix_acl_xattr_header )buffer;
299	posix_acl_xattr_entry *ext_entry = ext_acl->a_entries;
300	int real_size, n;
301
302	real_size = posix_acl_xattr_size(acl->a_count);
303	if (!buffer)
304	return real_size;
305	if (real_size > size) {
306	fprintf(stderr, "ACL: not enough space to convert (%d %d)\n", real_size, size);
307	return -1;
308	}
309
310	ext_acl->a_version = POSIX_ACL_XATTR_VERSION;
311	if (Bcvt)
312	swabst("1i", (u_char *)ext_acl);
313
314	for (n=0; n < acl->a_count; n++, ext_entry++) {
315	ext_entry->e_tag = acl->a_entries[n].e_tag;
316	ext_entry->e_perm = acl->a_entries[n].e_perm;
317	ext_entry->e_id = acl->a_entries[n].e_id;
318	if (Bcvt)
319	swabst("2s1i", (u_char *)ext_entry);
320	}
321	return real_size;
322	}
323
324	static struct posix_acl *
325	ext3_acl_from_disk(const void *value, size_t size)
326	{
327	const char end = (char )value + size;
328	int n, count;
329	struct posix_acl *acl;
330
331	if (!value)
332	return NULL;
333	if (size < sizeof(ext3_acl_header)) {
334	fprintf(stderr, "ACL size too little\n");
335	return NULL;
336	}
337	if (Bcvt)
338	swabst("1i", (u_char *)value);
339	if (((ext3_acl_header *)value)->a_version != EXT3_ACL_VERSION) {
340	fprintf(stderr, "ACL version unknown\n");
341	return NULL;
342	}
343	value = (char *)value + sizeof(ext3_acl_header);
344	count = ext3_acl_count(size);
345	if (count < 0) {
346	fprintf(stderr, "ACL bad count\n");
347	return NULL;
348	}
349	if (count == 0)
350	return NULL;
351	acl = malloc(sizeof(struct posix_acl) + count * sizeof(struct posix_acl_entry));
352	if (!acl) {
353	fprintf(stderr, "ACL malloc failed\n");
354	return NULL;
355	}
356	acl->a_count = count;
357
358	for (n=0; n < count; n++) {
359	if (Bcvt)
360	swabst("2s1i", (u_char *)value);
361	ext3_acl_entry entry = (ext3_acl_entry )value;
362	if ((char *)value + sizeof(ext3_acl_entry_short) > end)
363	goto fail;
364	acl->a_entries[n].e_tag = entry->e_tag;
365	acl->a_entries[n].e_perm = entry->e_perm;
366	switch(acl->a_entries[n].e_tag) {
367	case ACL_USER_OBJ:
368	case ACL_GROUP_OBJ:
369	case ACL_MASK:
370	case ACL_OTHER:
371	value = (char *)value + sizeof(ext3_acl_entry_short);
372	acl->a_entries[n].e_id = ACL_UNDEFINED_ID;
373	break;
374
375	case ACL_USER:
376	case ACL_GROUP:
377	value = (char *)value + sizeof(ext3_acl_entry);
378	if ((char *)value > end)
379	goto fail;
380	acl->a_entries[n].e_id = entry->e_id;
381	break;
382
383	default:
384	goto fail;
385	}
386	}
387	if (value != end)
388	goto fail;
389	return acl;
390
391	fail:
392	fprintf(stderr, "ACL bad entry\n");
393	free(acl);
394	return NULL;
395	}
396
cca7148b SP	397	/*
	398	* Dump code starts here :)
	399	*/
	400
	401	static int
	402	xattr_cb_list(char name, char value, int valuelen, void *private)
	403	{
	404	value[valuelen] = '\0';
	405	printf("EA: %s:%s\n", name, value);
	406
	407	return GOOD;
	408	}
	409
	410	static int
	411	xattr_cb_set(char name, char value, int valuelen, void *private)
	412	{
	413	char path = (char )private;
	414
	415	if (lsetxattr(path, name, value, valuelen, 0) < 0) {
	416	warn("lsetxattr %s failed", path);
	417	return FAIL;
	418	}
	419	return GOOD;
	420	}
	421
	422	static int
	423	xattr_cb_compare(char name, char value, int valuelen, void *private)
	424	{
	425	char path = (char )private;
	426	char valuef[XATTR_MAXSIZE];
	427	int valuesz;
	428
	429	valuesz = lgetxattr(path, name, valuef, XATTR_MAXSIZE);
	430	if (valuesz < 0) {
	431	warn("%s: lgetxattr failed\n", path);
	432	return FAIL;
	433	}
	434
	435	if (valuesz != valuelen) {
	436	fprintf(stderr, "%s: EA %s value changed\n", path, value);
	437	return FAIL;
	438	}
	439
	440	if (memcmp(value, valuef, valuelen)) {
	441	fprintf(stderr, "%s: EA %s value changed\n", path, value);
	442	return FAIL;
	443	}
	444
	445	return GOOD;
	446	}
	447
	448	static int
	449	xattr_verify(char *buffer)
	450	{
	451	struct ext2_xattr_entry *entry;
	452	char *end;
	453
	454	end = buffer + XATTR_MAXSIZE;
	455
	456	if (Bcvt)
	457	swabst("4i", (u_char *)buffer);
	458
	459	if (HDR(buffer)->h_magic != EXT2_XATTR_MAGIC &&
	460	HDR(buffer)->h_magic != EXT2_XATTR_MAGIC2) {
461	fprintf(stderr, "error in EA block 1\n");
462	fprintf(stderr, "magic = %x\n", HDR(buffer)->h_magic);
463
464	return FAIL;
465	}
466
467	/* check the on-disk data structure */
468	entry = FIRST_ENTRY(buffer);
469	if (Bcvt)
470	swabst("2b1s3i", (u_char *)entry);
471	while (!IS_LAST_ENTRY(entry)) {
472	struct ext2_xattr_entry *next = EXT2_XATTR_NEXT(entry);
473
474	if ((char *)next >= end) {
475	fprintf(stderr, "error in EA block\n");
476	return FAIL;
477	}
478	entry = next;
479	if (Bcvt)
480	swabst("2b1s3i", (u_char *)entry);
481	}
482	return GOOD;
483	}
484
485	static int
486	xattr_count(char buffer, int count)
487	{
488	struct ext2_xattr_entry *entry;
489	int result = 0;
490
491	/* list the attribute names */
492	for (entry = FIRST_ENTRY(buffer); !IS_LAST_ENTRY(entry);
493	entry = EXT2_XATTR_NEXT(entry))
494	result++;
495
496	*count = result;
497	return GOOD;
498	}
499
500	static int
501	xattr_walk(char buffer, int (xattr_cb)(char , char , int, void ), void private)
502	{
503	struct ext2_xattr_entry *entry;
504
505	/* list the attribute names */
506	for (entry = FIRST_ENTRY(buffer); !IS_LAST_ENTRY(entry);
507	entry = EXT2_XATTR_NEXT(entry)) {
508	char name[XATTR_MAXSIZE], value[XATTR_MAXSIZE];
509	int off;
b630baf0	510	int convertacl = 0;
cca7148b SP	511
	512	switch (entry->e_name_index) {
	513	case EXT2_XATTR_INDEX_USER:
	514	strcpy(name, "user.");
	515	break;
	516	case EXT2_XATTR_INDEX_POSIX_ACL_ACCESS:
b630baf0 SP	517	strcpy(name, "system.posix_acl_access");
	518	convertacl = 1;
	519	break;
cca7148b	520	case EXT2_XATTR_INDEX_POSIX_ACL_DEFAULT:
b630baf0 SP	521	strcpy(name, "system.posix_acl_default");
b630baf0 SP	522	convertacl = 1;
cca7148b SP	523	break;
	524	case EXT2_XATTR_INDEX_TRUSTED:
	525	strcpy(name, "trusted.");
	526	break;
	527	case EXT2_XATTR_INDEX_LUSTRE:
	528	strcpy(name, "lustre.");
	529	break;
	530	case EXT2_XATTR_INDEX_SECURITY:
	531	strcpy(name, "security.");
	532	break;
	533	default:
	534	fprintf(stderr, "Unknown EA index\n");
	535	return FAIL;
	536	}
	537
	538	off = strlen(name);
	539	memcpy(name + off, entry->e_name, entry->e_name_len);
	540	name[off + entry->e_name_len] = '\0';
	541
cca7148b SP	542	memcpy(value, buffer + VALUE_OFFSET(buffer, entry), entry->e_value_size);
cca7148b SP	543
b630baf0 SP	544	if (convertacl) {
	545	struct posix_acl *acl;
	546	int size;
	547
	548	acl = ext3_acl_from_disk(value, entry->e_value_size);
	549	if (!acl)
	550	return FAIL;
	551	size = posix_acl_to_xattr(acl, value, XATTR_MAXSIZE);
	552	if (size < 0)
	553	return FAIL;
	554	entry->e_value_size = size;
	555	free(acl);
	556	}
	557
cca7148b SP	558	if (xattr_cb(name, value, entry->e_value_size, private) != GOOD)
	559	return FAIL;
	560	}
	561
	562	return GOOD;
	563	}
	564
	565	int
	566	xattr_compare(char path, char buffer)
	567	{
	568	int countf, countt;
	569	char names = NULL, end_names, *name;
	570
	571	countf = llistxattr(path, NULL, 0);
	572	if (countf < 0) {
	573	warn("%s: llistxattr failed", path);
	574	return FAIL;
	575	}
	576
	577	names = malloc(countf + 1);
	578	if (!names) {
	579	warn("%s: llistxattr failed", path);
	580	return FAIL;
	581	}
	582
	583	countf = llistxattr(path, names, countf);
	584	if (countf < 0) {
	585	warn("%s: llistxattr failed", path);
	586	free(names);
	587	return FAIL;
	588	}
	589
	590	names[countf] = '\0';
	591	end_names = names + countf;
	592
	593	countf = 0;
	594	for (name = names; name != end_names; name = strchr(name, '\0') + 1) {
	595	if (!*name)
	596	continue;
	597	countf++;
	598	}
	599
	600	free(names);
	601
	602	if (buffer) {
	603	if (xattr_verify(buffer) == FAIL)
	604	return FAIL;
	605
	606	if (xattr_count(buffer, &countt) == FAIL)
	607	return FAIL;
	608	}
	609	else
	610	countt = 0;
	611
	612	if (countf != countt) {
	613	fprintf(stderr, "%s: EA count changed from %d to %d\n", path, countt, countf);
	614	return FAIL;
	615	}
	616
	617	if (!buffer)
	618	return GOOD;
	619
	620	return xattr_walk(buffer, xattr_cb_compare, path);
	621	}
622
623	int
624	xattr_extract(char path, char buffer)
625	{
626	if (dflag) {
627	fprintf(stderr, "xattr_extract(%s)\n", path);
628	xattr_walk(buffer, xattr_cb_list, NULL);
629	}
630
631	if (xattr_verify(buffer) == FAIL)
632	return FAIL;
633
634	return xattr_walk(buffer, xattr_cb_set, path);
635	}
636