fs/cifs/smb2transport.c

   1 /*
   2  *   fs/cifs/smb2transport.c
   3  *
   4  *   Copyright (C) International Business Machines  Corp., 2002, 2011
   5  *                 Etersoft, 2012
   6  *   Author(s): Steve French (sfrench@us.ibm.com)
   7  *              Jeremy Allison (jra@samba.org) 2006
   8  *              Pavel Shilovsky (pshilovsky@samba.org) 2012
   9  *
  10  *   This library is free software; you can redistribute it and/or modify
  11  *   it under the terms of the GNU Lesser General Public License as published
  12  *   by the Free Software Foundation; either version 2.1 of the License, or
  13  *   (at your option) any later version.
  14  *
  15  *   This library is distributed in the hope that it will be useful,
  16  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
  18  *   the GNU Lesser General Public License for more details.
  19  *
  20  *   You should have received a copy of the GNU Lesser General Public License
  21  *   along with this library; if not, write to the Free Software
  22  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  23  */
  24
  25 #include <linux/fs.h>
  26 #include <linux/list.h>
  27 #include <linux/wait.h>
  28 #include <linux/net.h>
  29 #include <linux/delay.h>
  30 #include <linux/uaccess.h>
  31 #include <asm/processor.h>
  32 #include <linux/mempool.h>
  33 #include "smb2pdu.h"
  34 #include "cifsglob.h"
  35 #include "cifsproto.h"
  36 #include "smb2proto.h"
  37 #include "cifs_debug.h"
  38 #include "smb2status.h"
  39
  40 /*
  41  * Set message id for the request. Should be called after wait_for_free_request
  42  * and when srv_mutex is held.
  43  */
  44 static inline void
  45 smb2_seq_num_into_buf(struct TCP_Server_Info *server, struct smb2_hdr *hdr)
  46 {
  47         hdr->MessageId = get_next_mid(server);
  48 }
  49
  50 static struct mid_q_entry *
  51 smb2_mid_entry_alloc(const struct smb2_hdr *smb_buffer,
  52                      struct TCP_Server_Info *server)
  53 {
  54         struct mid_q_entry *temp;
  55
  56         if (server == NULL) {
  57                 cERROR(1, "Null TCP session in smb2_mid_entry_alloc");
  58                 return NULL;
  59         }
  60
  61         temp = mempool_alloc(cifs_mid_poolp, GFP_NOFS);
  62         if (temp == NULL)
  63                 return temp;
  64         else {
  65                 memset(temp, 0, sizeof(struct mid_q_entry));
  66                 temp->mid = smb_buffer->MessageId;      /* always LE */
  67                 temp->pid = current->pid;
  68                 temp->command = smb_buffer->Command;    /* Always LE */
  69                 temp->when_alloc = jiffies;
  70                 temp->server = server;
  71
  72                 /*
  73                  * The default is for the mid to be synchronous, so the
  74                  * default callback just wakes up the current task.
  75                  */
  76                 temp->callback = cifs_wake_up_task;
  77                 temp->callback_data = current;
  78         }
  79
  80         atomic_inc(&midCount);
  81         temp->mid_state = MID_REQUEST_ALLOCATED;
  82         return temp;
  83 }
  84
  85 static int
  86 smb2_get_mid_entry(struct cifs_ses *ses, struct smb2_hdr *buf,
  87                    struct mid_q_entry **mid)
  88 {
  89         if (ses->server->tcpStatus == CifsExiting)
  90                 return -ENOENT;
  91
  92         if (ses->server->tcpStatus == CifsNeedReconnect) {
  93                 cFYI(1, "tcp session dead - return to caller to retry");
  94                 return -EAGAIN;
  95         }
  96
  97         if (ses->status != CifsGood) {
  98                 /* check if SMB2 session is bad because we are setting it up */
  99                 if ((buf->Command != SMB2_SESSION_SETUP) &&
 100                     (buf->Command != SMB2_NEGOTIATE))
 101                         return -EAGAIN;
 102                 /* else ok - we are setting up session */
 103         }
 104         *mid = smb2_mid_entry_alloc(buf, ses->server);
 105         if (*mid == NULL)
 106                 return -ENOMEM;
 107         spin_lock(&GlobalMid_Lock);
 108         list_add_tail(&(*mid)->qhead, &ses->server->pending_mid_q);
 109         spin_unlock(&GlobalMid_Lock);
 110         return 0;
 111 }
 112
 113 int
 114 smb2_check_receive(struct mid_q_entry *mid, struct TCP_Server_Info *server,
 115                    bool log_error)
 116 {
 117         unsigned int len = get_rfc1002_length(mid->resp_buf);
 118
 119         dump_smb(mid->resp_buf, min_t(u32, 80, len));
 120         /* convert the length into a more usable form */
 121         /* BB - uncomment with SMB2 signing implementation */
 122         /* if ((len > 24) &&
 123             (server->sec_mode & (SECMODE_SIGN_REQUIRED|SECMODE_SIGN_ENABLED))) {
 124                 if (smb2_verify_signature(mid->resp_buf, server))
 125                         cERROR(1, "Unexpected SMB signature");
 126         } */
 127
 128         return map_smb2_to_linux_error(mid->resp_buf, log_error);
 129 }
 130
 131 int
 132 smb2_setup_request(struct cifs_ses *ses, struct kvec *iov,
 133                    unsigned int nvec, struct mid_q_entry **ret_mid)
 134 {
 135         int rc;
 136         struct smb2_hdr *hdr = (struct smb2_hdr *)iov[0].iov_base;
 137         struct mid_q_entry *mid;
 138
 139         smb2_seq_num_into_buf(ses->server, hdr);
 140
 141         rc = smb2_get_mid_entry(ses, hdr, &mid);
 142         if (rc)
 143                 return rc;
 144         /* rc = smb2_sign_smb2(iov, nvec, ses->server);
 145         if (rc)
 146                 delete_mid(mid); */
 147         *ret_mid = mid;
 148         return rc;
 149 }
 150
 151 int
 152 smb2_setup_async_request(struct TCP_Server_Info *server, struct kvec *iov,
 153                          unsigned int nvec, struct mid_q_entry **ret_mid)
 154 {
 155         int rc = 0;
 156         struct smb2_hdr *hdr = (struct smb2_hdr *)iov[0].iov_base;
 157         struct mid_q_entry *mid;
 158
 159         smb2_seq_num_into_buf(server, hdr);
 160
 161         mid = smb2_mid_entry_alloc(hdr, server);
 162         if (mid == NULL)
 163                 return -ENOMEM;
 164
 165         /* rc = smb2_sign_smb2(iov, nvec, server);
 166         if (rc) {
 167                 DeleteMidQEntry(mid);
 168                 return rc;
 169         }*/
 170         *ret_mid = mid;
 171         return rc;
 172 }