| /* |
| * Copyright (C) International Business Machines Corp., 2000-2004 |
| * Copyright (C) Christoph Hellwig, 2002 |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License as published by |
| * the Free Software Foundation; either version 2 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 General Public License for more details. |
| * |
| * You should have received a copy of the GNU General Public License |
| * along with this program; if not, write to the Free Software |
| * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
| */ |
| |
| #include <linux/fs.h> |
| #include <linux/xattr.h> |
| #include <linux/posix_acl_xattr.h> |
| #include <linux/quotaops.h> |
| #include <linux/security.h> |
| #include "jfs_incore.h" |
| #include "jfs_superblock.h" |
| #include "jfs_dmap.h" |
| #include "jfs_debug.h" |
| #include "jfs_dinode.h" |
| #include "jfs_extent.h" |
| #include "jfs_metapage.h" |
| #include "jfs_xattr.h" |
| #include "jfs_acl.h" |
| |
| /* |
| * jfs_xattr.c: extended attribute service |
| * |
| * Overall design -- |
| * |
| * Format: |
| * |
| * Extended attribute lists (jfs_ea_list) consist of an overall size (32 bit |
| * value) and a variable (0 or more) number of extended attribute |
| * entries. Each extended attribute entry (jfs_ea) is a <name,value> double |
| * where <name> is constructed from a null-terminated ascii string |
| * (1 ... 255 bytes in the name) and <value> is arbitrary 8 bit data |
| * (1 ... 65535 bytes). The in-memory format is |
| * |
| * 0 1 2 4 4 + namelen + 1 |
| * +-------+--------+--------+----------------+-------------------+ |
| * | Flags | Name | Value | Name String \0 | Data . . . . | |
| * | | Length | Length | | | |
| * +-------+--------+--------+----------------+-------------------+ |
| * |
| * A jfs_ea_list then is structured as |
| * |
| * 0 4 4 + EA_SIZE(ea1) |
| * +------------+-------------------+--------------------+----- |
| * | Overall EA | First FEA Element | Second FEA Element | ..... |
| * | List Size | | | |
| * +------------+-------------------+--------------------+----- |
| * |
| * On-disk: |
| * |
| * FEALISTs are stored on disk using blocks allocated by dbAlloc() and |
| * written directly. An EA list may be in-lined in the inode if there is |
| * sufficient room available. |
| */ |
| |
| struct ea_buffer { |
| int flag; /* Indicates what storage xattr points to */ |
| int max_size; /* largest xattr that fits in current buffer */ |
| dxd_t new_ea; /* dxd to replace ea when modifying xattr */ |
| struct metapage *mp; /* metapage containing ea list */ |
| struct jfs_ea_list *xattr; /* buffer containing ea list */ |
| }; |
| |
| /* |
| * ea_buffer.flag values |
| */ |
| #define EA_INLINE 0x0001 |
| #define EA_EXTENT 0x0002 |
| #define EA_NEW 0x0004 |
| #define EA_MALLOC 0x0008 |
| |
| |
| /* |
| * These three routines are used to recognize on-disk extended attributes |
| * that are in a recognized namespace. If the attribute is not recognized, |
| * "os2." is prepended to the name |
| */ |
| static inline int is_os2_xattr(struct jfs_ea *ea) |
| { |
| /* |
| * Check for "system." |
| */ |
| if ((ea->namelen >= XATTR_SYSTEM_PREFIX_LEN) && |
| !strncmp(ea->name, XATTR_SYSTEM_PREFIX, XATTR_SYSTEM_PREFIX_LEN)) |
| return FALSE; |
| /* |
| * Check for "user." |
| */ |
| if ((ea->namelen >= XATTR_USER_PREFIX_LEN) && |
| !strncmp(ea->name, XATTR_USER_PREFIX, XATTR_USER_PREFIX_LEN)) |
| return FALSE; |
| /* |
| * Check for "security." |
| */ |
| if ((ea->namelen >= XATTR_SECURITY_PREFIX_LEN) && |
| !strncmp(ea->name, XATTR_SECURITY_PREFIX, |
| XATTR_SECURITY_PREFIX_LEN)) |
| return FALSE; |
| /* |
| * Check for "trusted." |
| */ |
| if ((ea->namelen >= XATTR_TRUSTED_PREFIX_LEN) && |
| !strncmp(ea->name, XATTR_TRUSTED_PREFIX, XATTR_TRUSTED_PREFIX_LEN)) |
| return FALSE; |
| /* |
| * Add any other valid namespace prefixes here |
| */ |
| |
| /* |
| * We assume it's OS/2's flat namespace |
| */ |
| return TRUE; |
| } |
| |
| static inline int name_size(struct jfs_ea *ea) |
| { |
| if (is_os2_xattr(ea)) |
| return ea->namelen + XATTR_OS2_PREFIX_LEN; |
| else |
| return ea->namelen; |
| } |
| |
| static inline int copy_name(char *buffer, struct jfs_ea *ea) |
| { |
| int len = ea->namelen; |
| |
| if (is_os2_xattr(ea)) { |
| memcpy(buffer, XATTR_OS2_PREFIX, XATTR_OS2_PREFIX_LEN); |
| buffer += XATTR_OS2_PREFIX_LEN; |
| len += XATTR_OS2_PREFIX_LEN; |
| } |
| memcpy(buffer, ea->name, ea->namelen); |
| buffer[ea->namelen] = 0; |
| |
| return len; |
| } |
| |
| /* Forward references */ |
| static void ea_release(struct inode *inode, struct ea_buffer *ea_buf); |
| |
| /* |
| * NAME: ea_write_inline |
| * |
| * FUNCTION: Attempt to write an EA inline if area is available |
| * |
| * PRE CONDITIONS: |
| * Already verified that the specified EA is small enough to fit inline |
| * |
| * PARAMETERS: |
| * ip - Inode pointer |
| * ealist - EA list pointer |
| * size - size of ealist in bytes |
| * ea - dxd_t structure to be filled in with necessary EA information |
| * if we successfully copy the EA inline |
| * |
| * NOTES: |
| * Checks if the inode's inline area is available. If so, copies EA inline |
| * and sets <ea> fields appropriately. Otherwise, returns failure, EA will |
| * have to be put into an extent. |
| * |
| * RETURNS: 0 for successful copy to inline area; -1 if area not available |
| */ |
| static int ea_write_inline(struct inode *ip, struct jfs_ea_list *ealist, |
| int size, dxd_t * ea) |
| { |
| struct jfs_inode_info *ji = JFS_IP(ip); |
| |
| /* |
| * Make sure we have an EA -- the NULL EA list is valid, but you |
| * can't copy it! |
| */ |
| if (ealist && size > sizeof (struct jfs_ea_list)) { |
| assert(size <= sizeof (ji->i_inline_ea)); |
| |
| /* |
| * See if the space is available or if it is already being |
| * used for an inline EA. |
| */ |
| if (!(ji->mode2 & INLINEEA) && !(ji->ea.flag & DXD_INLINE)) |
| return -EPERM; |
| |
| DXDsize(ea, size); |
| DXDlength(ea, 0); |
| DXDaddress(ea, 0); |
| memcpy(ji->i_inline_ea, ealist, size); |
| ea->flag = DXD_INLINE; |
| ji->mode2 &= ~INLINEEA; |
| } else { |
| ea->flag = 0; |
| DXDsize(ea, 0); |
| DXDlength(ea, 0); |
| DXDaddress(ea, 0); |
| |
| /* Free up INLINE area */ |
| if (ji->ea.flag & DXD_INLINE) |
| ji->mode2 |= INLINEEA; |
| } |
| |
| return 0; |
| } |
| |
| /* |
| * NAME: ea_write |
| * |
| * FUNCTION: Write an EA for an inode |
| * |
| * PRE CONDITIONS: EA has been verified |
| * |
| * PARAMETERS: |
| * ip - Inode pointer |
| * ealist - EA list pointer |
| * size - size of ealist in bytes |
| * ea - dxd_t structure to be filled in appropriately with where the |
| * EA was copied |
| * |
| * NOTES: Will write EA inline if able to, otherwise allocates blocks for an |
| * extent and synchronously writes it to those blocks. |
| * |
| * RETURNS: 0 for success; Anything else indicates failure |
| */ |
| static int ea_write(struct inode *ip, struct jfs_ea_list *ealist, int size, |
| dxd_t * ea) |
| { |
| struct super_block *sb = ip->i_sb; |
| struct jfs_inode_info *ji = JFS_IP(ip); |
| struct jfs_sb_info *sbi = JFS_SBI(sb); |
| int nblocks; |
| s64 blkno; |
| int rc = 0, i; |
| char *cp; |
| s32 nbytes, nb; |
| s32 bytes_to_write; |
| struct metapage *mp; |
| |
| /* |
| * Quick check to see if this is an in-linable EA. Short EAs |
| * and empty EAs are all in-linable, provided the space exists. |
| */ |
| if (!ealist || size <= sizeof (ji->i_inline_ea)) { |
| if (!ea_write_inline(ip, ealist, size, ea)) |
| return 0; |
| } |
| |
| /* figure out how many blocks we need */ |
| nblocks = (size + (sb->s_blocksize - 1)) >> sb->s_blocksize_bits; |
| |
| /* Allocate new blocks to quota. */ |
| if (DQUOT_ALLOC_BLOCK(ip, nblocks)) { |
| return -EDQUOT; |
| } |
| |
| rc = dbAlloc(ip, INOHINT(ip), nblocks, &blkno); |
| if (rc) { |
| /*Rollback quota allocation. */ |
| DQUOT_FREE_BLOCK(ip, nblocks); |
| return rc; |
| } |
| |
| /* |
| * Now have nblocks worth of storage to stuff into the FEALIST. |
| * loop over the FEALIST copying data into the buffer one page at |
| * a time. |
| */ |
| cp = (char *) ealist; |
| nbytes = size; |
| for (i = 0; i < nblocks; i += sbi->nbperpage) { |
| /* |
| * Determine how many bytes for this request, and round up to |
| * the nearest aggregate block size |
| */ |
| nb = min(PSIZE, nbytes); |
| bytes_to_write = |
| ((((nb + sb->s_blocksize - 1)) >> sb->s_blocksize_bits)) |
| << sb->s_blocksize_bits; |
| |
| if (!(mp = get_metapage(ip, blkno + i, bytes_to_write, 1))) { |
| rc = -EIO; |
| goto failed; |
| } |
| |
| memcpy(mp->data, cp, nb); |
| |
| /* |
| * We really need a way to propagate errors for |
| * forced writes like this one. --hch |
| * |
| * (__write_metapage => release_metapage => flush_metapage) |
| */ |
| #ifdef _JFS_FIXME |
| if ((rc = flush_metapage(mp))) { |
| /* |
| * the write failed -- this means that the buffer |
| * is still assigned and the blocks are not being |
| * used. this seems like the best error recovery |
| * we can get ... |
| */ |
| goto failed; |
| } |
| #else |
| flush_metapage(mp); |
| #endif |
| |
| cp += PSIZE; |
| nbytes -= nb; |
| } |
| |
| ea->flag = DXD_EXTENT; |
| DXDsize(ea, le32_to_cpu(ealist->size)); |
| DXDlength(ea, nblocks); |
| DXDaddress(ea, blkno); |
| |
| /* Free up INLINE area */ |
| if (ji->ea.flag & DXD_INLINE) |
| ji->mode2 |= INLINEEA; |
| |
| return 0; |
| |
| failed: |
| /* Rollback quota allocation. */ |
| DQUOT_FREE_BLOCK(ip, nblocks); |
| |
| dbFree(ip, blkno, nblocks); |
| return rc; |
| } |
| |
| /* |
| * NAME: ea_read_inline |
| * |
| * FUNCTION: Read an inlined EA into user's buffer |
| * |
| * PARAMETERS: |
| * ip - Inode pointer |
| * ealist - Pointer to buffer to fill in with EA |
| * |
| * RETURNS: 0 |
| */ |
| static int ea_read_inline(struct inode *ip, struct jfs_ea_list *ealist) |
| { |
| struct jfs_inode_info *ji = JFS_IP(ip); |
| int ea_size = sizeDXD(&ji->ea); |
| |
| if (ea_size == 0) { |
| ealist->size = 0; |
| return 0; |
| } |
| |
| /* Sanity Check */ |
| if ((sizeDXD(&ji->ea) > sizeof (ji->i_inline_ea))) |
| return -EIO; |
| if (le32_to_cpu(((struct jfs_ea_list *) &ji->i_inline_ea)->size) |
| != ea_size) |
| return -EIO; |
| |
| memcpy(ealist, ji->i_inline_ea, ea_size); |
| return 0; |
| } |
| |
| /* |
| * NAME: ea_read |
| * |
| * FUNCTION: copy EA data into user's buffer |
| * |
| * PARAMETERS: |
| * ip - Inode pointer |
| * ealist - Pointer to buffer to fill in with EA |
| * |
| * NOTES: If EA is inline calls ea_read_inline() to copy EA. |
| * |
| * RETURNS: 0 for success; other indicates failure |
| */ |
| static int ea_read(struct inode *ip, struct jfs_ea_list *ealist) |
| { |
| struct super_block *sb = ip->i_sb; |
| struct jfs_inode_info *ji = JFS_IP(ip); |
| struct jfs_sb_info *sbi = JFS_SBI(sb); |
| int nblocks; |
| s64 blkno; |
| char *cp = (char *) ealist; |
| int i; |
| int nbytes, nb; |
| s32 bytes_to_read; |
| struct metapage *mp; |
| |
| /* quick check for in-line EA */ |
| if (ji->ea.flag & DXD_INLINE) |
| return ea_read_inline(ip, ealist); |
| |
| nbytes = sizeDXD(&ji->ea); |
| if (!nbytes) { |
| jfs_error(sb, "ea_read: nbytes is 0"); |
| return -EIO; |
| } |
| |
| /* |
| * Figure out how many blocks were allocated when this EA list was |
| * originally written to disk. |
| */ |
| nblocks = lengthDXD(&ji->ea) << sbi->l2nbperpage; |
| blkno = addressDXD(&ji->ea) << sbi->l2nbperpage; |
| |
| /* |
| * I have found the disk blocks which were originally used to store |
| * the FEALIST. now i loop over each contiguous block copying the |
| * data into the buffer. |
| */ |
| for (i = 0; i < nblocks; i += sbi->nbperpage) { |
| /* |
| * Determine how many bytes for this request, and round up to |
| * the nearest aggregate block size |
| */ |
| nb = min(PSIZE, nbytes); |
| bytes_to_read = |
| ((((nb + sb->s_blocksize - 1)) >> sb->s_blocksize_bits)) |
| << sb->s_blocksize_bits; |
| |
| if (!(mp = read_metapage(ip, blkno + i, bytes_to_read, 1))) |
| return -EIO; |
| |
| memcpy(cp, mp->data, nb); |
| release_metapage(mp); |
| |
| cp += PSIZE; |
| nbytes -= nb; |
| } |
| |
| return 0; |
| } |
| |
| /* |
| * NAME: ea_get |
| * |
| * FUNCTION: Returns buffer containing existing extended attributes. |
| * The size of the buffer will be the larger of the existing |
| * attributes size, or min_size. |
| * |
| * The buffer, which may be inlined in the inode or in the |
| * page cache must be release by calling ea_release or ea_put |
| * |
| * PARAMETERS: |
| * inode - Inode pointer |
| * ea_buf - Structure to be populated with ealist and its metadata |
| * min_size- minimum size of buffer to be returned |
| * |
| * RETURNS: 0 for success; Other indicates failure |
| */ |
| static int ea_get(struct inode *inode, struct ea_buffer *ea_buf, int min_size) |
| { |
| struct jfs_inode_info *ji = JFS_IP(inode); |
| struct super_block *sb = inode->i_sb; |
| int size; |
| int ea_size = sizeDXD(&ji->ea); |
| int blocks_needed, current_blocks; |
| s64 blkno; |
| int rc; |
| int quota_allocation = 0; |
| |
| /* When fsck.jfs clears a bad ea, it doesn't clear the size */ |
| if (ji->ea.flag == 0) |
| ea_size = 0; |
| |
| if (ea_size == 0) { |
| if (min_size == 0) { |
| ea_buf->flag = 0; |
| ea_buf->max_size = 0; |
| ea_buf->xattr = NULL; |
| return 0; |
| } |
| if ((min_size <= sizeof (ji->i_inline_ea)) && |
| (ji->mode2 & INLINEEA)) { |
| ea_buf->flag = EA_INLINE | EA_NEW; |
| ea_buf->max_size = sizeof (ji->i_inline_ea); |
| ea_buf->xattr = (struct jfs_ea_list *) ji->i_inline_ea; |
| DXDlength(&ea_buf->new_ea, 0); |
| DXDaddress(&ea_buf->new_ea, 0); |
| ea_buf->new_ea.flag = DXD_INLINE; |
| DXDsize(&ea_buf->new_ea, min_size); |
| return 0; |
| } |
| current_blocks = 0; |
| } else if (ji->ea.flag & DXD_INLINE) { |
| if (min_size <= sizeof (ji->i_inline_ea)) { |
| ea_buf->flag = EA_INLINE; |
| ea_buf->max_size = sizeof (ji->i_inline_ea); |
| ea_buf->xattr = (struct jfs_ea_list *) ji->i_inline_ea; |
| goto size_check; |
| } |
| current_blocks = 0; |
| } else { |
| if (!(ji->ea.flag & DXD_EXTENT)) { |
| jfs_error(sb, "ea_get: invalid ea.flag)"); |
| return -EIO; |
| } |
| current_blocks = (ea_size + sb->s_blocksize - 1) >> |
| sb->s_blocksize_bits; |
| } |
| size = max(min_size, ea_size); |
| |
| if (size > PSIZE) { |
| /* |
| * To keep the rest of the code simple. Allocate a |
| * contiguous buffer to work with |
| */ |
| ea_buf->xattr = kmalloc(size, GFP_KERNEL); |
| if (ea_buf->xattr == NULL) |
| return -ENOMEM; |
| |
| ea_buf->flag = EA_MALLOC; |
| ea_buf->max_size = (size + sb->s_blocksize - 1) & |
| ~(sb->s_blocksize - 1); |
| |
| if (ea_size == 0) |
| return 0; |
| |
| if ((rc = ea_read(inode, ea_buf->xattr))) { |
| kfree(ea_buf->xattr); |
| ea_buf->xattr = NULL; |
| return rc; |
| } |
| goto size_check; |
| } |
| blocks_needed = (min_size + sb->s_blocksize - 1) >> |
| sb->s_blocksize_bits; |
| |
| if (blocks_needed > current_blocks) { |
| /* Allocate new blocks to quota. */ |
| if (DQUOT_ALLOC_BLOCK(inode, blocks_needed)) |
| return -EDQUOT; |
| |
| quota_allocation = blocks_needed; |
| |
| rc = dbAlloc(inode, INOHINT(inode), (s64) blocks_needed, |
| &blkno); |
| if (rc) |
| goto clean_up; |
| |
| DXDlength(&ea_buf->new_ea, blocks_needed); |
| DXDaddress(&ea_buf->new_ea, blkno); |
| ea_buf->new_ea.flag = DXD_EXTENT; |
| DXDsize(&ea_buf->new_ea, min_size); |
| |
| ea_buf->flag = EA_EXTENT | EA_NEW; |
| |
| ea_buf->mp = get_metapage(inode, blkno, |
| blocks_needed << sb->s_blocksize_bits, |
| 1); |
| if (ea_buf->mp == NULL) { |
| dbFree(inode, blkno, (s64) blocks_needed); |
| rc = -EIO; |
| goto clean_up; |
| } |
| ea_buf->xattr = ea_buf->mp->data; |
| ea_buf->max_size = (min_size + sb->s_blocksize - 1) & |
| ~(sb->s_blocksize - 1); |
| if (ea_size == 0) |
| return 0; |
| if ((rc = ea_read(inode, ea_buf->xattr))) { |
| discard_metapage(ea_buf->mp); |
| dbFree(inode, blkno, (s64) blocks_needed); |
| goto clean_up; |
| } |
| goto size_check; |
| } |
| ea_buf->flag = EA_EXTENT; |
| ea_buf->mp = read_metapage(inode, addressDXD(&ji->ea), |
| lengthDXD(&ji->ea) << sb->s_blocksize_bits, |
| 1); |
| if (ea_buf->mp == NULL) { |
| rc = -EIO; |
| goto clean_up; |
| } |
| ea_buf->xattr = ea_buf->mp->data; |
| ea_buf->max_size = (ea_size + sb->s_blocksize - 1) & |
| ~(sb->s_blocksize - 1); |
| |
| size_check: |
| if (EALIST_SIZE(ea_buf->xattr) != ea_size) { |
| printk(KERN_ERR "ea_get: invalid extended attribute\n"); |
| dump_mem("xattr", ea_buf->xattr, ea_size); |
| ea_release(inode, ea_buf); |
| rc = -EIO; |
| goto clean_up; |
| } |
| |
| return ea_size; |
| |
| clean_up: |
| /* Rollback quota allocation */ |
| if (quota_allocation) |
| DQUOT_FREE_BLOCK(inode, quota_allocation); |
| |
| return (rc); |
| } |
| |
| static void ea_release(struct inode *inode, struct ea_buffer *ea_buf) |
| { |
| if (ea_buf->flag & EA_MALLOC) |
| kfree(ea_buf->xattr); |
| else if (ea_buf->flag & EA_EXTENT) { |
| assert(ea_buf->mp); |
| release_metapage(ea_buf->mp); |
| |
| if (ea_buf->flag & EA_NEW) |
| dbFree(inode, addressDXD(&ea_buf->new_ea), |
| lengthDXD(&ea_buf->new_ea)); |
| } |
| } |
| |
| static int ea_put(tid_t tid, struct inode *inode, struct ea_buffer *ea_buf, |
| int new_size) |
| { |
| struct jfs_inode_info *ji = JFS_IP(inode); |
| unsigned long old_blocks, new_blocks; |
| int rc = 0; |
| |
| if (new_size == 0) { |
| ea_release(inode, ea_buf); |
| ea_buf = NULL; |
| } else if (ea_buf->flag & EA_INLINE) { |
| assert(new_size <= sizeof (ji->i_inline_ea)); |
| ji->mode2 &= ~INLINEEA; |
| ea_buf->new_ea.flag = DXD_INLINE; |
| DXDsize(&ea_buf->new_ea, new_size); |
| DXDaddress(&ea_buf->new_ea, 0); |
| DXDlength(&ea_buf->new_ea, 0); |
| } else if (ea_buf->flag & EA_MALLOC) { |
| rc = ea_write(inode, ea_buf->xattr, new_size, &ea_buf->new_ea); |
| kfree(ea_buf->xattr); |
| } else if (ea_buf->flag & EA_NEW) { |
| /* We have already allocated a new dxd */ |
| flush_metapage(ea_buf->mp); |
| } else { |
| /* ->xattr must point to original ea's metapage */ |
| rc = ea_write(inode, ea_buf->xattr, new_size, &ea_buf->new_ea); |
| discard_metapage(ea_buf->mp); |
| } |
| if (rc) |
| return rc; |
| |
| old_blocks = new_blocks = 0; |
| |
| if (ji->ea.flag & DXD_EXTENT) { |
| invalidate_dxd_metapages(inode, ji->ea); |
| old_blocks = lengthDXD(&ji->ea); |
| } |
| |
| if (ea_buf) { |
| txEA(tid, inode, &ji->ea, &ea_buf->new_ea); |
| if (ea_buf->new_ea.flag & DXD_EXTENT) { |
| new_blocks = lengthDXD(&ea_buf->new_ea); |
| if (ji->ea.flag & DXD_INLINE) |
| ji->mode2 |= INLINEEA; |
| } |
| ji->ea = ea_buf->new_ea; |
| } else { |
| txEA(tid, inode, &ji->ea, NULL); |
| if (ji->ea.flag & DXD_INLINE) |
| ji->mode2 |= INLINEEA; |
| ji->ea.flag = 0; |
| ji->ea.size = 0; |
| } |
| |
| /* If old blocks exist, they must be removed from quota allocation. */ |
| if (old_blocks) |
| DQUOT_FREE_BLOCK(inode, old_blocks); |
| |
| inode->i_ctime = CURRENT_TIME; |
| |
| return 0; |
| } |
| |
| /* |
| * can_set_system_xattr |
| * |
| * This code is specific to the system.* namespace. It contains policy |
| * which doesn't belong in the main xattr codepath. |
| */ |
| static int can_set_system_xattr(struct inode *inode, const char *name, |
| const void *value, size_t value_len) |
| { |
| #ifdef CONFIG_JFS_POSIX_ACL |
| struct posix_acl *acl; |
| int rc; |
| |
| if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER)) |
| return -EPERM; |
| |
| /* |
| * POSIX_ACL_XATTR_ACCESS is tied to i_mode |
| */ |
| if (strcmp(name, POSIX_ACL_XATTR_ACCESS) == 0) { |
| acl = posix_acl_from_xattr(value, value_len); |
| if (IS_ERR(acl)) { |
| rc = PTR_ERR(acl); |
| printk(KERN_ERR "posix_acl_from_xattr returned %d\n", |
| rc); |
| return rc; |
| } |
| if (acl) { |
| mode_t mode = inode->i_mode; |
| rc = posix_acl_equiv_mode(acl, &mode); |
| posix_acl_release(acl); |
| if (rc < 0) { |
| printk(KERN_ERR |
| "posix_acl_equiv_mode returned %d\n", |
| rc); |
| return rc; |
| } |
| inode->i_mode = mode; |
| mark_inode_dirty(inode); |
| } |
| /* |
| * We're changing the ACL. Get rid of the cached one |
| */ |
| acl =JFS_IP(inode)->i_acl; |
| if (acl != JFS_ACL_NOT_CACHED) |
| posix_acl_release(acl); |
| JFS_IP(inode)->i_acl = JFS_ACL_NOT_CACHED; |
| |
| return 0; |
| } else if (strcmp(name, POSIX_ACL_XATTR_DEFAULT) == 0) { |
| acl = posix_acl_from_xattr(value, value_len); |
| if (IS_ERR(acl)) { |
| rc = PTR_ERR(acl); |
| printk(KERN_ERR "posix_acl_from_xattr returned %d\n", |
| rc); |
| return rc; |
| } |
| posix_acl_release(acl); |
| |
| /* |
| * We're changing the default ACL. Get rid of the cached one |
| */ |
| acl =JFS_IP(inode)->i_default_acl; |
| if (acl && (acl != JFS_ACL_NOT_CACHED)) |
| posix_acl_release(acl); |
| JFS_IP(inode)->i_default_acl = JFS_ACL_NOT_CACHED; |
| |
| return 0; |
| } |
| #endif /* CONFIG_JFS_POSIX_ACL */ |
| return -EOPNOTSUPP; |
| } |
| |
| static int can_set_xattr(struct inode *inode, const char *name, |
| const void *value, size_t value_len) |
| { |
| if (IS_RDONLY(inode)) |
| return -EROFS; |
| |
| if (IS_IMMUTABLE(inode) || IS_APPEND(inode)) |
| return -EPERM; |
| |
| if(strncmp(name, XATTR_SYSTEM_PREFIX, XATTR_SYSTEM_PREFIX_LEN) == 0) |
| /* |
| * "system.*" |
| */ |
| return can_set_system_xattr(inode, name, value, value_len); |
| |
| if(strncmp(name, XATTR_TRUSTED_PREFIX, XATTR_TRUSTED_PREFIX_LEN) == 0) |
| return (capable(CAP_SYS_ADMIN) ? 0 : -EPERM); |
| |
| #ifdef CONFIG_JFS_SECURITY |
| if (strncmp(name, XATTR_SECURITY_PREFIX, XATTR_SECURITY_PREFIX_LEN) |
| == 0) |
| return 0; /* Leave it to the security module */ |
| #endif |
| |
| if((strncmp(name, XATTR_USER_PREFIX, XATTR_USER_PREFIX_LEN) != 0) && |
| (strncmp(name, XATTR_OS2_PREFIX, XATTR_OS2_PREFIX_LEN) != 0)) |
| return -EOPNOTSUPP; |
| |
| if (!S_ISREG(inode->i_mode) && |
| (!S_ISDIR(inode->i_mode) || inode->i_mode &S_ISVTX)) |
| return -EPERM; |
| |
| return permission(inode, MAY_WRITE, NULL); |
| } |
| |
| int __jfs_setxattr(tid_t tid, struct inode *inode, const char *name, |
| const void *value, size_t value_len, int flags) |
| { |
| struct jfs_ea_list *ealist; |
| struct jfs_ea *ea, *old_ea = NULL, *next_ea = NULL; |
| struct ea_buffer ea_buf; |
| int old_ea_size = 0; |
| int xattr_size; |
| int new_size; |
| int namelen = strlen(name); |
| char *os2name = NULL; |
| int found = 0; |
| int rc; |
| int length; |
| |
| if (strncmp(name, XATTR_OS2_PREFIX, XATTR_OS2_PREFIX_LEN) == 0) { |
| os2name = kmalloc(namelen - XATTR_OS2_PREFIX_LEN + 1, |
| GFP_KERNEL); |
| if (!os2name) |
| return -ENOMEM; |
| strcpy(os2name, name + XATTR_OS2_PREFIX_LEN); |
| name = os2name; |
| namelen -= XATTR_OS2_PREFIX_LEN; |
| } |
| |
| down_write(&JFS_IP(inode)->xattr_sem); |
| |
| xattr_size = ea_get(inode, &ea_buf, 0); |
| if (xattr_size < 0) { |
| rc = xattr_size; |
| goto out; |
| } |
| |
| again: |
| ealist = (struct jfs_ea_list *) ea_buf.xattr; |
| new_size = sizeof (struct jfs_ea_list); |
| |
| if (xattr_size) { |
| for (ea = FIRST_EA(ealist); ea < END_EALIST(ealist); |
| ea = NEXT_EA(ea)) { |
| if ((namelen == ea->namelen) && |
| (memcmp(name, ea->name, namelen) == 0)) { |
| found = 1; |
| if (flags & XATTR_CREATE) { |
| rc = -EEXIST; |
| goto release; |
| } |
| old_ea = ea; |
| old_ea_size = EA_SIZE(ea); |
| next_ea = NEXT_EA(ea); |
| } else |
| new_size += EA_SIZE(ea); |
| } |
| } |
| |
| if (!found) { |
| if (flags & XATTR_REPLACE) { |
| rc = -ENODATA; |
| goto release; |
| } |
| if (value == NULL) { |
| rc = 0; |
| goto release; |
| } |
| } |
| if (value) |
| new_size += sizeof (struct jfs_ea) + namelen + 1 + value_len; |
| |
| if (new_size > ea_buf.max_size) { |
| /* |
| * We need to allocate more space for merged ea list. |
| * We should only have loop to again: once. |
| */ |
| ea_release(inode, &ea_buf); |
| xattr_size = ea_get(inode, &ea_buf, new_size); |
| if (xattr_size < 0) { |
| rc = xattr_size; |
| goto out; |
| } |
| goto again; |
| } |
| |
| /* Remove old ea of the same name */ |
| if (found) { |
| /* number of bytes following target EA */ |
| length = (char *) END_EALIST(ealist) - (char *) next_ea; |
| if (length > 0) |
| memmove(old_ea, next_ea, length); |
| xattr_size -= old_ea_size; |
| } |
| |
| /* Add new entry to the end */ |
| if (value) { |
| if (xattr_size == 0) |
| /* Completely new ea list */ |
| xattr_size = sizeof (struct jfs_ea_list); |
| |
| ea = (struct jfs_ea *) ((char *) ealist + xattr_size); |
| ea->flag = 0; |
| ea->namelen = namelen; |
| ea->valuelen = (cpu_to_le16(value_len)); |
| memcpy(ea->name, name, namelen); |
| ea->name[namelen] = 0; |
| if (value_len) |
| memcpy(&ea->name[namelen + 1], value, value_len); |
| xattr_size += EA_SIZE(ea); |
| } |
| |
| /* DEBUG - If we did this right, these number match */ |
| if (xattr_size != new_size) { |
| printk(KERN_ERR |
| "jfs_xsetattr: xattr_size = %d, new_size = %d\n", |
| xattr_size, new_size); |
| |
| rc = -EINVAL; |
| goto release; |
| } |
| |
| /* |
| * If we're left with an empty list, there's no ea |
| */ |
| if (new_size == sizeof (struct jfs_ea_list)) |
| new_size = 0; |
| |
| ealist->size = cpu_to_le32(new_size); |
| |
| rc = ea_put(tid, inode, &ea_buf, new_size); |
| |
| goto out; |
| release: |
| ea_release(inode, &ea_buf); |
| out: |
| up_write(&JFS_IP(inode)->xattr_sem); |
| |
| kfree(os2name); |
| |
| return rc; |
| } |
| |
| int jfs_setxattr(struct dentry *dentry, const char *name, const void *value, |
| size_t value_len, int flags) |
| { |
| struct inode *inode = dentry->d_inode; |
| struct jfs_inode_info *ji = JFS_IP(inode); |
| int rc; |
| tid_t tid; |
| |
| if ((rc = can_set_xattr(inode, name, value, value_len))) |
| return rc; |
| |
| if (value == NULL) { /* empty EA, do not remove */ |
| value = ""; |
| value_len = 0; |
| } |
| |
| tid = txBegin(inode->i_sb, 0); |
| down(&ji->commit_sem); |
| rc = __jfs_setxattr(tid, dentry->d_inode, name, value, value_len, |
| flags); |
| if (!rc) |
| rc = txCommit(tid, 1, &inode, 0); |
| txEnd(tid); |
| up(&ji->commit_sem); |
| |
| return rc; |
| } |
| |
| static int can_get_xattr(struct inode *inode, const char *name) |
| { |
| #ifdef CONFIG_JFS_SECURITY |
| if(strncmp(name, XATTR_SECURITY_PREFIX, XATTR_SECURITY_PREFIX_LEN) == 0) |
| return 0; |
| #endif |
| |
| if(strncmp(name, XATTR_TRUSTED_PREFIX, XATTR_TRUSTED_PREFIX_LEN) == 0) |
| return (capable(CAP_SYS_ADMIN) ? 0 : -EPERM); |
| |
| if(strncmp(name, XATTR_SYSTEM_PREFIX, XATTR_SYSTEM_PREFIX_LEN) == 0) |
| return 0; |
| |
| return permission(inode, MAY_READ, NULL); |
| } |
| |
| ssize_t __jfs_getxattr(struct inode *inode, const char *name, void *data, |
| size_t buf_size) |
| { |
| struct jfs_ea_list *ealist; |
| struct jfs_ea *ea; |
| struct ea_buffer ea_buf; |
| int xattr_size; |
| ssize_t size; |
| int namelen = strlen(name); |
| char *os2name = NULL; |
| int rc; |
| char *value; |
| |
| if ((rc = can_get_xattr(inode, name))) |
| return rc; |
| |
| if (strncmp(name, XATTR_OS2_PREFIX, XATTR_OS2_PREFIX_LEN) == 0) { |
| os2name = kmalloc(namelen - XATTR_OS2_PREFIX_LEN + 1, |
| GFP_KERNEL); |
| if (!os2name) |
| return -ENOMEM; |
| strcpy(os2name, name + XATTR_OS2_PREFIX_LEN); |
| name = os2name; |
| namelen -= XATTR_OS2_PREFIX_LEN; |
| } |
| |
| down_read(&JFS_IP(inode)->xattr_sem); |
| |
| xattr_size = ea_get(inode, &ea_buf, 0); |
| |
| if (xattr_size < 0) { |
| size = xattr_size; |
| goto out; |
| } |
| |
| if (xattr_size == 0) |
| goto not_found; |
| |
| ealist = (struct jfs_ea_list *) ea_buf.xattr; |
| |
| /* Find the named attribute */ |
| for (ea = FIRST_EA(ealist); ea < END_EALIST(ealist); ea = NEXT_EA(ea)) |
| if ((namelen == ea->namelen) && |
| memcmp(name, ea->name, namelen) == 0) { |
| /* Found it */ |
| size = le16_to_cpu(ea->valuelen); |
| if (!data) |
| goto release; |
| else if (size > buf_size) { |
| size = -ERANGE; |
| goto release; |
| } |
| value = ((char *) &ea->name) + ea->namelen + 1; |
| memcpy(data, value, size); |
| goto release; |
| } |
| not_found: |
| size = -ENODATA; |
| release: |
| ea_release(inode, &ea_buf); |
| out: |
| up_read(&JFS_IP(inode)->xattr_sem); |
| |
| kfree(os2name); |
| |
| return size; |
| } |
| |
| ssize_t jfs_getxattr(struct dentry *dentry, const char *name, void *data, |
| size_t buf_size) |
| { |
| int err; |
| |
| err = __jfs_getxattr(dentry->d_inode, name, data, buf_size); |
| |
| return err; |
| } |
| |
| /* |
| * No special permissions are needed to list attributes except for trusted.* |
| */ |
| static inline int can_list(struct jfs_ea *ea) |
| { |
| return (strncmp(ea->name, XATTR_TRUSTED_PREFIX, |
| XATTR_TRUSTED_PREFIX_LEN) || |
| capable(CAP_SYS_ADMIN)); |
| } |
| |
| ssize_t jfs_listxattr(struct dentry * dentry, char *data, size_t buf_size) |
| { |
| struct inode *inode = dentry->d_inode; |
| char *buffer; |
| ssize_t size = 0; |
| int xattr_size; |
| struct jfs_ea_list *ealist; |
| struct jfs_ea *ea; |
| struct ea_buffer ea_buf; |
| |
| down_read(&JFS_IP(inode)->xattr_sem); |
| |
| xattr_size = ea_get(inode, &ea_buf, 0); |
| if (xattr_size < 0) { |
| size = xattr_size; |
| goto out; |
| } |
| |
| if (xattr_size == 0) |
| goto release; |
| |
| ealist = (struct jfs_ea_list *) ea_buf.xattr; |
| |
| /* compute required size of list */ |
| for (ea = FIRST_EA(ealist); ea < END_EALIST(ealist); ea = NEXT_EA(ea)) { |
| if (can_list(ea)) |
| size += name_size(ea) + 1; |
| } |
| |
| if (!data) |
| goto release; |
| |
| if (size > buf_size) { |
| size = -ERANGE; |
| goto release; |
| } |
| |
| /* Copy attribute names to buffer */ |
| buffer = data; |
| for (ea = FIRST_EA(ealist); ea < END_EALIST(ealist); ea = NEXT_EA(ea)) { |
| if (can_list(ea)) { |
| int namelen = copy_name(buffer, ea); |
| buffer += namelen + 1; |
| } |
| } |
| |
| release: |
| ea_release(inode, &ea_buf); |
| out: |
| up_read(&JFS_IP(inode)->xattr_sem); |
| return size; |
| } |
| |
| int jfs_removexattr(struct dentry *dentry, const char *name) |
| { |
| struct inode *inode = dentry->d_inode; |
| struct jfs_inode_info *ji = JFS_IP(inode); |
| int rc; |
| tid_t tid; |
| |
| if ((rc = can_set_xattr(inode, name, NULL, 0))) |
| return rc; |
| |
| tid = txBegin(inode->i_sb, 0); |
| down(&ji->commit_sem); |
| rc = __jfs_setxattr(tid, dentry->d_inode, name, NULL, 0, XATTR_REPLACE); |
| if (!rc) |
| rc = txCommit(tid, 1, &inode, 0); |
| txEnd(tid); |
| up(&ji->commit_sem); |
| |
| return rc; |
| } |
| |
| #ifdef CONFIG_JFS_SECURITY |
| int jfs_init_security(tid_t tid, struct inode *inode, struct inode *dir) |
| { |
| int rc; |
| size_t len; |
| void *value; |
| char *suffix; |
| char *name; |
| |
| rc = security_inode_init_security(inode, dir, &suffix, &value, &len); |
| if (rc) { |
| if (rc == -EOPNOTSUPP) |
| return 0; |
| return rc; |
| } |
| name = kmalloc(XATTR_SECURITY_PREFIX_LEN + 1 + strlen(suffix), |
| GFP_NOFS); |
| if (!name) { |
| rc = -ENOMEM; |
| goto kmalloc_failed; |
| } |
| strcpy(name, XATTR_SECURITY_PREFIX); |
| strcpy(name + XATTR_SECURITY_PREFIX_LEN, suffix); |
| |
| rc = __jfs_setxattr(tid, inode, name, value, len, 0); |
| |
| kfree(name); |
| kmalloc_failed: |
| kfree(suffix); |
| kfree(value); |
| |
| return rc; |
| } |
| #endif |