/* * 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/capability.h> #include <linux/fs.h> #include <linux/xattr.h> #include <linux/posix_acl_xattr.h> #include <linux/slab.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 static int is_known_namespace(const char *name) { if (strncmp(name, XATTR_SYSTEM_PREFIX, XATTR_SYSTEM_PREFIX_LEN) && strncmp(name, XATTR_USER_PREFIX, XATTR_USER_PREFIX_LEN) && strncmp(name, XATTR_SECURITY_PREFIX, XATTR_SECURITY_PREFIX_LEN) && strncmp(name, XATTR_TRUSTED_PREFIX, XATTR_TRUSTED_PREFIX_LEN)) return false; return true; } /* * 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 int is_os2_xattr(struct jfs_ea *ea) { return !is_known_namespace(ea->name); } 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. */ rc = dquot_alloc_block(ip, nblocks); if (rc) return rc; 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. */ rc = dquot_alloc_block(inode, blocks_needed); if (rc) 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"); print_hex_dump(KERN_ERR, "", DUMP_PREFIX_ADDRESS, 16, 1, ea_buf->xattr, ea_size, 1); 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 (!inode_owner_or_capable(inode)) 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) { rc = posix_acl_equiv_mode(acl, &inode->i_mode); posix_acl_release(acl); if (rc < 0) { printk(KERN_ERR "posix_acl_equiv_mode returned %d\n", rc); return rc; } mark_inode_dirty(inode); } /* * We're changing the ACL. Get rid of the cached one */ forget_cached_acl(inode, ACL_TYPE_ACCESS); 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 */ forget_cached_acl(inode, ACL_TYPE_DEFAULT); return 0; } #endif /* CONFIG_JFS_POSIX_ACL */ return -EOPNOTSUPP; } /* * Most of the permission checking is done by xattr_permission in the vfs. * The local file system is responsible for handling the system.* namespace. * We also need to verify that this is a namespace that we recognize. */ static int can_set_xattr(struct inode *inode, const char *name, const void *value, size_t value_len) { if (!strncmp(name, XATTR_SYSTEM_PREFIX, XATTR_SYSTEM_PREFIX_LEN)) return can_set_system_xattr(inode, name, value, value_len); if (!strncmp(name, XATTR_OS2_PREFIX, XATTR_OS2_PREFIX_LEN)) { /* * This makes sure that we aren't trying to set an * attribute in a different namespace by prefixing it * with "os2." */ if (is_known_namespace(name + XATTR_OS2_PREFIX_LEN)) return -EOPNOTSUPP; return 0; } /* * Don't allow setting an attribute in an unknown namespace. */ if (strncmp(name, XATTR_TRUSTED_PREFIX, XATTR_TRUSTED_PREFIX_LEN) && strncmp(name, XATTR_SECURITY_PREFIX, XATTR_SECURITY_PREFIX_LEN) && strncmp(name, XATTR_USER_PREFIX, XATTR_USER_PREFIX_LEN)) return -EOPNOTSUPP; return 0; } 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); mutex_lock(&ji->commit_mutex); rc = __jfs_setxattr(tid, dentry->d_inode, name, value, value_len, flags); if (!rc) rc = txCommit(tid, 1, &inode, 0); txEnd(tid); mutex_unlock(&ji->commit_mutex); return rc; } 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 *value; 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); return size; } ssize_t jfs_getxattr(struct dentry *dentry, const char *name, void *data, size_t buf_size) { int err; if (strncmp(name, XATTR_OS2_PREFIX, XATTR_OS2_PREFIX_LEN) == 0) { /* * skip past "os2." prefix */ name += XATTR_OS2_PREFIX_LEN; /* * Don't allow retrieving properly prefixed attributes * by prepending them with "os2." */ if (is_known_namespace(name)) return -EOPNOTSUPP; } 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); mutex_lock(&ji->commit_mutex); rc = __jfs_setxattr(tid, dentry->d_inode, name, NULL, 0, XATTR_REPLACE); if (!rc) rc = txCommit(tid, 1, &inode, 0); txEnd(tid); mutex_unlock(&ji->commit_mutex); return rc; } #ifdef CONFIG_JFS_SECURITY int jfs_initxattrs(struct inode *inode, const struct xattr *xattr_array, void *fs_info) { const struct xattr *xattr; tid_t *tid = fs_info; char *name; int err = 0; for (xattr = xattr_array; xattr->name != NULL; xattr++) { name = kmalloc(XATTR_SECURITY_PREFIX_LEN + strlen(xattr->name) + 1, GFP_NOFS); if (!name) { err = -ENOMEM; break; } strcpy(name, XATTR_SECURITY_PREFIX); strcpy(name + XATTR_SECURITY_PREFIX_LEN, xattr->name); err = __jfs_setxattr(*tid, inode, name, xattr->value, xattr->value_len, 0); kfree(name); if (err < 0) break; } return err; } int jfs_init_security(tid_t tid, struct inode *inode, struct inode *dir, const struct qstr *qstr) { return security_inode_init_security(inode, dir, qstr, &jfs_initxattrs, &tid); } #endif