/* * fs/cifs/dir.c * * vfs operations that deal with dentries * * Copyright (C) International Business Machines Corp., 2002,2003 * Author(s): Steve French (sfrench@us.ibm.com) * * This library 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 library 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 library; 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/stat.h> #include <linux/slab.h> #include <linux/namei.h> #include "cifsfs.h" #include "cifspdu.h" #include "cifsglob.h" #include "cifsproto.h" #include "cifs_debug.h" #include "cifs_fs_sb.h" void renew_parental_timestamps(struct dentry *direntry) { /* BB check if there is a way to get the kernel to do this or if we really need this */ do { direntry->d_time = jiffies; direntry = direntry->d_parent; } while (!IS_ROOT(direntry)); } /* Note: caller must free return buffer */ char * build_path_from_dentry(struct dentry *direntry) { struct dentry *temp; int namelen = 0; char *full_path; if(direntry == NULL) return NULL; /* not much we can do if dentry is freed and we need to reopen the file after it was closed implicitly when the server crashed */ cifs_bp_rename_retry: for (temp = direntry; !IS_ROOT(temp);) { namelen += (1 + temp->d_name.len); temp = temp->d_parent; if(temp == NULL) { cERROR(1,("corrupt dentry")); return NULL; } } full_path = kmalloc(namelen+1, GFP_KERNEL); if(full_path == NULL) return full_path; full_path[namelen] = 0; /* trailing null */ for (temp = direntry; !IS_ROOT(temp);) { namelen -= 1 + temp->d_name.len; if (namelen < 0) { break; } else { full_path[namelen] = '\\'; strncpy(full_path + namelen + 1, temp->d_name.name, temp->d_name.len); cFYI(0, (" name: %s ", full_path + namelen)); } temp = temp->d_parent; if(temp == NULL) { cERROR(1,("corrupt dentry")); kfree(full_path); return NULL; } } if (namelen != 0) { cERROR(1, ("We did not end path lookup where we expected namelen is %d", namelen)); /* presumably this is only possible if we were racing with a rename of one of the parent directories (we can not lock the dentries above us to prevent this, but retrying should be harmless) */ kfree(full_path); namelen = 0; goto cifs_bp_rename_retry; } return full_path; } /* char * build_wildcard_path_from_dentry(struct dentry *direntry) { if(full_path == NULL) return full_path; full_path[namelen] = '\\'; full_path[namelen+1] = '*'; full_path[namelen+2] = 0; BB remove above eight lines BB */ /* Inode operations in similar order to how they appear in the Linux file fs.h */ int cifs_create(struct inode *inode, struct dentry *direntry, int mode, struct nameidata *nd) { int rc = -ENOENT; int xid; int oplock = 0; int desiredAccess = GENERIC_READ | GENERIC_WRITE; __u16 fileHandle; struct cifs_sb_info *cifs_sb; struct cifsTconInfo *pTcon; char *full_path = NULL; FILE_ALL_INFO * buf = NULL; struct inode *newinode = NULL; struct cifsFileInfo * pCifsFile = NULL; struct cifsInodeInfo * pCifsInode; int disposition = FILE_OVERWRITE_IF; int write_only = FALSE; xid = GetXid(); cifs_sb = CIFS_SB(inode->i_sb); pTcon = cifs_sb->tcon; down(&direntry->d_sb->s_vfs_rename_sem); full_path = build_path_from_dentry(direntry); up(&direntry->d_sb->s_vfs_rename_sem); if(full_path == NULL) { FreeXid(xid); return -ENOMEM; } if(nd && (nd->flags & LOOKUP_OPEN)) { int oflags = nd->intent.open.flags; desiredAccess = 0; if (oflags & FMODE_READ) desiredAccess |= GENERIC_READ; if (oflags & FMODE_WRITE) { desiredAccess |= GENERIC_WRITE; if (!(oflags & FMODE_READ)) write_only = TRUE; } if((oflags & (O_CREAT | O_EXCL)) == (O_CREAT | O_EXCL)) disposition = FILE_CREATE; else if((oflags & (O_CREAT | O_TRUNC)) == (O_CREAT | O_TRUNC)) disposition = FILE_OVERWRITE_IF; else if((oflags & O_CREAT) == O_CREAT) disposition = FILE_OPEN_IF; else { cFYI(1,("Create flag not set in create function")); } } /* BB add processing to set equivalent of mode - e.g. via CreateX with ACLs */ if (oplockEnabled) oplock = REQ_OPLOCK; buf = kmalloc(sizeof(FILE_ALL_INFO),GFP_KERNEL); if(buf == NULL) { kfree(full_path); FreeXid(xid); return -ENOMEM; } rc = CIFSSMBOpen(xid, pTcon, full_path, disposition, desiredAccess, CREATE_NOT_DIR, &fileHandle, &oplock, buf, cifs_sb->local_nls, cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR); if (rc) { cFYI(1, ("cifs_create returned 0x%x ", rc)); } else { /* If Open reported that we actually created a file then we now have to set the mode if possible */ if ((cifs_sb->tcon->ses->capabilities & CAP_UNIX) && (oplock & CIFS_CREATE_ACTION)) if(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SET_UID) { CIFSSMBUnixSetPerms(xid, pTcon, full_path, mode, (__u64)current->euid, (__u64)current->egid, 0 /* dev */, cifs_sb->local_nls, cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR); } else { CIFSSMBUnixSetPerms(xid, pTcon, full_path, mode, (__u64)-1, (__u64)-1, 0 /* dev */, cifs_sb->local_nls, cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR); } else { /* BB implement via Windows security descriptors */ /* eg CIFSSMBWinSetPerms(xid,pTcon,full_path,mode,-1,-1,local_nls);*/ /* could set r/o dos attribute if mode & 0222 == 0 */ } /* BB server might mask mode so we have to query for Unix case*/ if (pTcon->ses->capabilities & CAP_UNIX) rc = cifs_get_inode_info_unix(&newinode, full_path, inode->i_sb,xid); else { rc = cifs_get_inode_info(&newinode, full_path, buf, inode->i_sb,xid); if(newinode) newinode->i_mode = mode; } if (rc != 0) { cFYI(1,("Create worked but get_inode_info failed with rc = %d", rc)); } else { direntry->d_op = &cifs_dentry_ops; d_instantiate(direntry, newinode); } if((nd->flags & LOOKUP_OPEN) == FALSE) { /* mknod case - do not leave file open */ CIFSSMBClose(xid, pTcon, fileHandle); } else if(newinode) { pCifsFile = kmalloc(sizeof (struct cifsFileInfo), GFP_KERNEL); if(pCifsFile == NULL) goto cifs_create_out; memset((char *)pCifsFile, 0, sizeof (struct cifsFileInfo)); pCifsFile->netfid = fileHandle; pCifsFile->pid = current->tgid; pCifsFile->pInode = newinode; pCifsFile->invalidHandle = FALSE; pCifsFile->closePend = FALSE; init_MUTEX(&pCifsFile->fh_sem); /* set the following in open now pCifsFile->pfile = file; */ write_lock(&GlobalSMBSeslock); list_add(&pCifsFile->tlist,&pTcon->openFileList); pCifsInode = CIFS_I(newinode); if(pCifsInode) { /* if readable file instance put first in list*/ if (write_only == TRUE) { list_add_tail(&pCifsFile->flist, &pCifsInode->openFileList); } else { list_add(&pCifsFile->flist, &pCifsInode->openFileList); } if((oplock & 0xF) == OPLOCK_EXCLUSIVE) { pCifsInode->clientCanCacheAll = TRUE; pCifsInode->clientCanCacheRead = TRUE; cFYI(1,("Exclusive Oplock for inode %p", newinode)); } else if((oplock & 0xF) == OPLOCK_READ) pCifsInode->clientCanCacheRead = TRUE; } write_unlock(&GlobalSMBSeslock); } } cifs_create_out: kfree(buf); kfree(full_path); FreeXid(xid); return rc; } int cifs_mknod(struct inode *inode, struct dentry *direntry, int mode, dev_t device_number) { int rc = -EPERM; int xid; struct cifs_sb_info *cifs_sb; struct cifsTconInfo *pTcon; char *full_path = NULL; struct inode * newinode = NULL; if (!old_valid_dev(device_number)) return -EINVAL; xid = GetXid(); cifs_sb = CIFS_SB(inode->i_sb); pTcon = cifs_sb->tcon; down(&direntry->d_sb->s_vfs_rename_sem); full_path = build_path_from_dentry(direntry); up(&direntry->d_sb->s_vfs_rename_sem); if(full_path == NULL) rc = -ENOMEM; if (full_path && (pTcon->ses->capabilities & CAP_UNIX)) { if(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SET_UID) { rc = CIFSSMBUnixSetPerms(xid, pTcon, full_path, mode,(__u64)current->euid,(__u64)current->egid, device_number, cifs_sb->local_nls, cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR); } else { rc = CIFSSMBUnixSetPerms(xid, pTcon, full_path, mode, (__u64)-1, (__u64)-1, device_number, cifs_sb->local_nls, cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR); } if(!rc) { rc = cifs_get_inode_info_unix(&newinode, full_path, inode->i_sb,xid); direntry->d_op = &cifs_dentry_ops; if(rc == 0) d_instantiate(direntry, newinode); } } kfree(full_path); FreeXid(xid); return rc; } struct dentry * cifs_lookup(struct inode *parent_dir_inode, struct dentry *direntry, struct nameidata *nd) { int xid; int rc = 0; /* to get around spurious gcc warning, set to zero here */ struct cifs_sb_info *cifs_sb; struct cifsTconInfo *pTcon; struct inode *newInode = NULL; char *full_path = NULL; xid = GetXid(); cFYI(1, (" parent inode = 0x%p name is: %s and dentry = 0x%p", parent_dir_inode, direntry->d_name.name, direntry)); /* BB Add check of incoming data - e.g. frame not longer than maximum SMB - let server check the namelen BB */ /* check whether path exists */ cifs_sb = CIFS_SB(parent_dir_inode->i_sb); pTcon = cifs_sb->tcon; /* can not grab the rename sem here since it would deadlock in the cases (beginning of sys_rename itself) in which we already have the sb rename sem */ full_path = build_path_from_dentry(direntry); if(full_path == NULL) { FreeXid(xid); return ERR_PTR(-ENOMEM); } if (direntry->d_inode != NULL) { cFYI(1, (" non-NULL inode in lookup")); } else { cFYI(1, (" NULL inode in lookup")); } cFYI(1, (" Full path: %s inode = 0x%p", full_path, direntry->d_inode)); if (pTcon->ses->capabilities & CAP_UNIX) rc = cifs_get_inode_info_unix(&newInode, full_path, parent_dir_inode->i_sb,xid); else rc = cifs_get_inode_info(&newInode, full_path, NULL, parent_dir_inode->i_sb,xid); if ((rc == 0) && (newInode != NULL)) { direntry->d_op = &cifs_dentry_ops; d_add(direntry, newInode); /* since paths are not looked up by component - the parent directories are presumed to be good here */ renew_parental_timestamps(direntry); } else if (rc == -ENOENT) { rc = 0; d_add(direntry, NULL); } else { cERROR(1,("Error 0x%x on cifs_get_inode_info in lookup of %s", rc,full_path)); /* BB special case check for Access Denied - watch security exposure of returning dir info implicitly via different rc if file exists or not but no access BB */ } kfree(full_path); FreeXid(xid); return ERR_PTR(rc); } static int cifs_d_revalidate(struct dentry *direntry, struct nameidata *nd) { int isValid = 1; /* lock_kernel(); *//* surely we do not want to lock the kernel for a whole network round trip which could take seconds */ if (direntry->d_inode) { if (cifs_revalidate(direntry)) { /* unlock_kernel(); */ return 0; } } else { cFYI(1, ("In cifs_d_revalidate with no inode but name = %s and dentry 0x%p", direntry->d_name.name, direntry)); } /* unlock_kernel(); */ return isValid; } /* static int cifs_d_delete(struct dentry *direntry) { int rc = 0; cFYI(1, ("In cifs d_delete, name = %s", direntry->d_name.name)); return rc; } */ struct dentry_operations cifs_dentry_ops = { .d_revalidate = cifs_d_revalidate, /* d_delete: cifs_d_delete, *//* not needed except for debugging */ /* no need for d_hash, d_compare, d_release, d_iput ... yet. BB confirm this BB */ };