diff options
Diffstat (limited to 'fs/cifs/misc.c')
-rw-r--r-- | fs/cifs/misc.c | 516 |
1 files changed, 516 insertions, 0 deletions
diff --git a/fs/cifs/misc.c b/fs/cifs/misc.c new file mode 100644 index 00000000000..7b38d3059a8 --- /dev/null +++ b/fs/cifs/misc.c @@ -0,0 +1,516 @@ +/* + * fs/cifs/misc.c + * + * Copyright (C) International Business Machines Corp., 2002,2004 + * 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/slab.h> +#include <linux/ctype.h> +#include <linux/mempool.h> +#include "cifspdu.h" +#include "cifsglob.h" +#include "cifsproto.h" +#include "cifs_debug.h" +#include "smberr.h" +#include "nterr.h" + +extern mempool_t *cifs_sm_req_poolp; +extern mempool_t *cifs_req_poolp; +extern struct task_struct * oplockThread; + +static __u16 GlobalMid; /* multiplex id - rotating counter */ + +/* The xid serves as a useful identifier for each incoming vfs request, + in a similar way to the mid which is useful to track each sent smb, + and CurrentXid can also provide a running counter (although it + will eventually wrap past zero) of the total vfs operations handled + since the cifs fs was mounted */ + +unsigned int +_GetXid(void) +{ + unsigned int xid; + + spin_lock(&GlobalMid_Lock); + GlobalTotalActiveXid++; + if (GlobalTotalActiveXid > GlobalMaxActiveXid) + GlobalMaxActiveXid = GlobalTotalActiveXid; /* keep high water mark for number of simultaneous vfs ops in our filesystem */ + xid = GlobalCurrentXid++; + spin_unlock(&GlobalMid_Lock); + return xid; +} + +void +_FreeXid(unsigned int xid) +{ + spin_lock(&GlobalMid_Lock); + /* if(GlobalTotalActiveXid == 0) + BUG(); */ + GlobalTotalActiveXid--; + spin_unlock(&GlobalMid_Lock); +} + +struct cifsSesInfo * +sesInfoAlloc(void) +{ + struct cifsSesInfo *ret_buf; + + ret_buf = + (struct cifsSesInfo *) kmalloc(sizeof (struct cifsSesInfo), + GFP_KERNEL); + if (ret_buf) { + memset(ret_buf, 0, sizeof (struct cifsSesInfo)); + write_lock(&GlobalSMBSeslock); + atomic_inc(&sesInfoAllocCount); + ret_buf->status = CifsNew; + list_add(&ret_buf->cifsSessionList, &GlobalSMBSessionList); + init_MUTEX(&ret_buf->sesSem); + write_unlock(&GlobalSMBSeslock); + } + return ret_buf; +} + +void +sesInfoFree(struct cifsSesInfo *buf_to_free) +{ + if (buf_to_free == NULL) { + cFYI(1, ("Null buffer passed to sesInfoFree")); + return; + } + + write_lock(&GlobalSMBSeslock); + atomic_dec(&sesInfoAllocCount); + list_del(&buf_to_free->cifsSessionList); + write_unlock(&GlobalSMBSeslock); + if (buf_to_free->serverOS) + kfree(buf_to_free->serverOS); + if (buf_to_free->serverDomain) + kfree(buf_to_free->serverDomain); + if (buf_to_free->serverNOS) + kfree(buf_to_free->serverNOS); + if (buf_to_free->password) + kfree(buf_to_free->password); + kfree(buf_to_free); +} + +struct cifsTconInfo * +tconInfoAlloc(void) +{ + struct cifsTconInfo *ret_buf; + ret_buf = + (struct cifsTconInfo *) kmalloc(sizeof (struct cifsTconInfo), + GFP_KERNEL); + if (ret_buf) { + memset(ret_buf, 0, sizeof (struct cifsTconInfo)); + write_lock(&GlobalSMBSeslock); + atomic_inc(&tconInfoAllocCount); + list_add(&ret_buf->cifsConnectionList, + &GlobalTreeConnectionList); + ret_buf->tidStatus = CifsNew; + INIT_LIST_HEAD(&ret_buf->openFileList); + init_MUTEX(&ret_buf->tconSem); +#ifdef CONFIG_CIFS_STATS + spin_lock_init(&ret_buf->stat_lock); +#endif + write_unlock(&GlobalSMBSeslock); + } + return ret_buf; +} + +void +tconInfoFree(struct cifsTconInfo *buf_to_free) +{ + if (buf_to_free == NULL) { + cFYI(1, ("Null buffer passed to tconInfoFree")); + return; + } + write_lock(&GlobalSMBSeslock); + atomic_dec(&tconInfoAllocCount); + list_del(&buf_to_free->cifsConnectionList); + write_unlock(&GlobalSMBSeslock); + if (buf_to_free->nativeFileSystem) + kfree(buf_to_free->nativeFileSystem); + kfree(buf_to_free); +} + +struct smb_hdr * +cifs_buf_get(void) +{ + struct smb_hdr *ret_buf = NULL; + +/* We could use negotiated size instead of max_msgsize - + but it may be more efficient to always alloc same size + albeit slightly larger than necessary and maxbuffersize + defaults to this and can not be bigger */ + ret_buf = + (struct smb_hdr *) mempool_alloc(cifs_req_poolp, SLAB_KERNEL | SLAB_NOFS); + + /* clear the first few header bytes */ + /* for most paths, more is cleared in header_assemble */ + if (ret_buf) { + memset(ret_buf, 0, sizeof(struct smb_hdr) + 3); + atomic_inc(&bufAllocCount); + } + + return ret_buf; +} + +void +cifs_buf_release(void *buf_to_free) +{ + + if (buf_to_free == NULL) { + /* cFYI(1, ("Null buffer passed to cifs_buf_release"));*/ + return; + } + mempool_free(buf_to_free,cifs_req_poolp); + + atomic_dec(&bufAllocCount); + return; +} + +struct smb_hdr * +cifs_small_buf_get(void) +{ + struct smb_hdr *ret_buf = NULL; + +/* We could use negotiated size instead of max_msgsize - + but it may be more efficient to always alloc same size + albeit slightly larger than necessary and maxbuffersize + defaults to this and can not be bigger */ + ret_buf = + (struct smb_hdr *) mempool_alloc(cifs_sm_req_poolp, SLAB_KERNEL | SLAB_NOFS); + if (ret_buf) { + /* No need to clear memory here, cleared in header assemble */ + /* memset(ret_buf, 0, sizeof(struct smb_hdr) + 27);*/ + atomic_inc(&smBufAllocCount); + } + return ret_buf; +} + +void +cifs_small_buf_release(void *buf_to_free) +{ + + if (buf_to_free == NULL) { + cFYI(1, ("Null buffer passed to cifs_small_buf_release")); + return; + } + mempool_free(buf_to_free,cifs_sm_req_poolp); + + atomic_dec(&smBufAllocCount); + return; +} + +void +header_assemble(struct smb_hdr *buffer, char smb_command /* command */ , + const struct cifsTconInfo *treeCon, int word_count + /* length of fixed section (word count) in two byte units */) +{ + struct list_head* temp_item; + struct cifsSesInfo * ses; + char *temp = (char *) buffer; + + memset(temp,0,MAX_CIFS_HDR_SIZE); + + buffer->smb_buf_length = + (2 * word_count) + sizeof (struct smb_hdr) - + 4 /* RFC 1001 length field does not count */ + + 2 /* for bcc field itself */ ; + /* Note that this is the only network field that has to be converted to big endian and it is done just before we send it */ + + buffer->Protocol[0] = 0xFF; + buffer->Protocol[1] = 'S'; + buffer->Protocol[2] = 'M'; + buffer->Protocol[3] = 'B'; + buffer->Command = smb_command; + buffer->Flags = 0x00; /* case sensitive */ + buffer->Flags2 = SMBFLG2_KNOWS_LONG_NAMES; + buffer->Pid = cpu_to_le16((__u16)current->tgid); + buffer->PidHigh = cpu_to_le16((__u16)(current->tgid >> 16)); + spin_lock(&GlobalMid_Lock); + GlobalMid++; + buffer->Mid = GlobalMid; + spin_unlock(&GlobalMid_Lock); + if (treeCon) { + buffer->Tid = treeCon->tid; + if (treeCon->ses) { + if (treeCon->ses->capabilities & CAP_UNICODE) + buffer->Flags2 |= SMBFLG2_UNICODE; + if (treeCon->ses->capabilities & CAP_STATUS32) { + buffer->Flags2 |= SMBFLG2_ERR_STATUS; + } + + buffer->Uid = treeCon->ses->Suid; /* always in LE format */ + if(multiuser_mount != 0) { + /* For the multiuser case, there are few obvious technically */ + /* possible mechanisms to match the local linux user (uid) */ + /* to a valid remote smb user (smb_uid): */ + /* 1) Query Winbind (or other local pam/nss daemon */ + /* for userid/password/logon_domain or credential */ + /* 2) Query Winbind for uid to sid to username mapping */ + /* and see if we have a matching password for existing*/ + /* session for that user perhas getting password by */ + /* adding a new pam_cifs module that stores passwords */ + /* so that the cifs vfs can get at that for all logged*/ + /* on users */ + /* 3) (Which is the mechanism we have chosen) */ + /* Search through sessions to the same server for a */ + /* a match on the uid that was passed in on mount */ + /* with the current processes uid (or euid?) and use */ + /* that smb uid. If no existing smb session for */ + /* that uid found, use the default smb session ie */ + /* the smb session for the volume mounted which is */ + /* the same as would be used if the multiuser mount */ + /* flag were disabled. */ + + /* BB Add support for establishing new tCon and SMB Session */ + /* with userid/password pairs found on the smb session */ + /* for other target tcp/ip addresses BB */ + if(current->uid != treeCon->ses->linux_uid) { + cFYI(1,("Multiuser mode and UID did not match tcon uid ")); + read_lock(&GlobalSMBSeslock); + list_for_each(temp_item, &GlobalSMBSessionList) { + ses = list_entry(temp_item, struct cifsSesInfo, cifsSessionList); + if(ses->linux_uid == current->uid) { + if(ses->server == treeCon->ses->server) { + cFYI(1,("found matching uid substitute right smb_uid")); + buffer->Uid = ses->Suid; + break; + } else { + /* BB eventually call cifs_setup_session here */ + cFYI(1,("local UID found but smb sess with this server does not exist")); + } + } + } + read_unlock(&GlobalSMBSeslock); + } + } + } + if (treeCon->Flags & SMB_SHARE_IS_IN_DFS) + buffer->Flags2 |= SMBFLG2_DFS; + if((treeCon->ses) && (treeCon->ses->server)) + if(treeCon->ses->server->secMode & + (SECMODE_SIGN_REQUIRED | SECMODE_SIGN_ENABLED)) + buffer->Flags2 |= SMBFLG2_SECURITY_SIGNATURE; + } + +/* endian conversion of flags is now done just before sending */ + buffer->WordCount = (char) word_count; + return; +} + +int +checkSMBhdr(struct smb_hdr *smb, __u16 mid) +{ + /* Make sure that this really is an SMB, that it is a response, + and that the message ids match */ + if ((*(__le32 *) smb->Protocol == cpu_to_le32(0x424d53ff)) && + (mid == smb->Mid)) { + if(smb->Flags & SMBFLG_RESPONSE) + return 0; + else { + /* only one valid case where server sends us request */ + if(smb->Command == SMB_COM_LOCKING_ANDX) + return 0; + else + cERROR(1, ("Rcvd Request not response ")); + } + } else { /* bad signature or mid */ + if (*(__le32 *) smb->Protocol != cpu_to_le32(0x424d53ff)) + cERROR(1, + ("Bad protocol string signature header %x ", + *(unsigned int *) smb->Protocol)); + if (mid != smb->Mid) + cERROR(1, ("Mids do not match")); + } + cERROR(1, ("bad smb detected. The Mid=%d", smb->Mid)); + return 1; +} + +int +checkSMB(struct smb_hdr *smb, __u16 mid, int length) +{ + __u32 len = be32_to_cpu(smb->smb_buf_length); + cFYI(0, + ("Entering checkSMB with Length: %x, smb_buf_length: %x ", + length, len)); + if (((unsigned int)length < 2 + sizeof (struct smb_hdr)) || + (len > CIFSMaxBufSize + MAX_CIFS_HDR_SIZE - 4)) { + if ((unsigned int)length < 2 + sizeof (struct smb_hdr)) { + if (((unsigned int)length >= + sizeof (struct smb_hdr) - 1) + && (smb->Status.CifsError != 0)) { + smb->WordCount = 0; + return 0; /* some error cases do not return wct and bcc */ + } else { + cERROR(1, ("Length less than smb header size")); + } + + } + if (len > CIFSMaxBufSize + MAX_CIFS_HDR_SIZE - 4) + cERROR(1, + ("smb_buf_length greater than MaxBufSize")); + cERROR(1, + ("bad smb detected. Illegal length. The mid=%d", + smb->Mid)); + return 1; + } + + if (checkSMBhdr(smb, mid)) + return 1; + + if ((4 + len != smbCalcSize(smb)) + || (4 + len != (unsigned int)length)) { + return 0; + } else { + cERROR(1, ("smbCalcSize %x ", smbCalcSize(smb))); + cERROR(1, + ("bad smb size detected. The Mid=%d", smb->Mid)); + return 1; + } +} +int +is_valid_oplock_break(struct smb_hdr *buf) +{ + struct smb_com_lock_req * pSMB = (struct smb_com_lock_req *)buf; + struct list_head *tmp; + struct list_head *tmp1; + struct cifsTconInfo *tcon; + struct cifsFileInfo *netfile; + + cFYI(1,("Checking for oplock break or dnotify response")); + if((pSMB->hdr.Command == SMB_COM_NT_TRANSACT) && + (pSMB->hdr.Flags & SMBFLG_RESPONSE)) { + struct smb_com_transaction_change_notify_rsp * pSMBr = + (struct smb_com_transaction_change_notify_rsp *)buf; + struct file_notify_information * pnotify; + __u32 data_offset = 0; + if(pSMBr->ByteCount > sizeof(struct file_notify_information)) { + data_offset = le32_to_cpu(pSMBr->DataOffset); + + pnotify = (struct file_notify_information *)((char *)&pSMBr->hdr.Protocol + + data_offset); + cFYI(1,("dnotify on %s with action: 0x%x",pnotify->FileName, + pnotify->Action)); /* BB removeme BB */ + /* cifs_dump_mem("Received notify Data is: ",buf,sizeof(struct smb_hdr)+60); */ + return TRUE; + } + if(pSMBr->hdr.Status.CifsError) { + cFYI(1,("notify err 0x%d",pSMBr->hdr.Status.CifsError)); + return TRUE; + } + return FALSE; + } + if(pSMB->hdr.Command != SMB_COM_LOCKING_ANDX) + return FALSE; + if(pSMB->hdr.Flags & SMBFLG_RESPONSE) { + /* no sense logging error on invalid handle on oplock + break - harmless race between close request and oplock + break response is expected from time to time writing out + large dirty files cached on the client */ + if ((NT_STATUS_INVALID_HANDLE) == + le32_to_cpu(pSMB->hdr.Status.CifsError)) { + cFYI(1,("invalid handle on oplock break")); + return TRUE; + } else if (ERRbadfid == + le16_to_cpu(pSMB->hdr.Status.DosError.Error)) { + return TRUE; + } else { + return FALSE; /* on valid oplock brk we get "request" */ + } + } + if(pSMB->hdr.WordCount != 8) + return FALSE; + + cFYI(1,(" oplock type 0x%d level 0x%d",pSMB->LockType,pSMB->OplockLevel)); + if(!(pSMB->LockType & LOCKING_ANDX_OPLOCK_RELEASE)) + return FALSE; + + /* look up tcon based on tid & uid */ + read_lock(&GlobalSMBSeslock); + list_for_each(tmp, &GlobalTreeConnectionList) { + tcon = list_entry(tmp, struct cifsTconInfo, cifsConnectionList); + if (tcon->tid == buf->Tid) { +#ifdef CONFIG_CIFS_STATS + atomic_inc(&tcon->num_oplock_brks); +#endif + list_for_each(tmp1,&tcon->openFileList){ + netfile = list_entry(tmp1,struct cifsFileInfo,tlist); + if(pSMB->Fid == netfile->netfid) { + struct cifsInodeInfo *pCifsInode; + read_unlock(&GlobalSMBSeslock); + cFYI(1,("Matching file id, processing oplock break")); + pCifsInode = + CIFS_I(netfile->pInode); + pCifsInode->clientCanCacheAll = FALSE; + if(pSMB->OplockLevel == 0) + pCifsInode->clientCanCacheRead = FALSE; + pCifsInode->oplockPending = TRUE; + AllocOplockQEntry(netfile->pInode, netfile->netfid, tcon); + cFYI(1,("about to wake up oplock thd")); + wake_up_process(oplockThread); + return TRUE; + } + } + read_unlock(&GlobalSMBSeslock); + cFYI(1,("No matching file for oplock break on connection")); + return TRUE; + } + } + read_unlock(&GlobalSMBSeslock); + cFYI(1,("Can not process oplock break for non-existent connection")); + return TRUE; +} + +void +dump_smb(struct smb_hdr *smb_buf, int smb_buf_length) +{ + int i, j; + char debug_line[17]; + unsigned char *buffer; + + if (traceSMB == 0) + return; + + buffer = (unsigned char *) smb_buf; + for (i = 0, j = 0; i < smb_buf_length; i++, j++) { + if (i % 8 == 0) { /* we have reached the beginning of line */ + printk(KERN_DEBUG "| "); + j = 0; + } + printk("%0#4x ", buffer[i]); + debug_line[2 * j] = ' '; + if (isprint(buffer[i])) + debug_line[1 + (2 * j)] = buffer[i]; + else + debug_line[1 + (2 * j)] = '_'; + + if (i % 8 == 7) { /* we have reached end of line, time to print ascii */ + debug_line[16] = 0; + printk(" | %s\n", debug_line); + } + } + for (; j < 8; j++) { + printk(" "); + debug_line[2 * j] = ' '; + debug_line[1 + (2 * j)] = ' '; + } + printk( " | %s\n", debug_line); + return; +} |