source3/smbd/smb2_negprot.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    Core SMB2 server
   4
   5    Copyright (C) Stefan Metzmacher 2009
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 3 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  19 */
  20
  21 #include "includes.h"
  22 #include "smbd/smbd.h"
  23 #include "smbd/globals.h"
  24 #include "../libcli/smb/smb_common.h"
  25
  26 /*
  27  * this is the entry point if SMB2 is selected via
  28  * the SMB negprot
  29  */
  30 void reply_smb2002(struct smb_request *req, uint16_t choice)
  31 {
  32         uint8_t *smb2_inbuf;
  33         uint8_t *smb2_hdr;
  34         uint8_t *smb2_body;
  35         uint8_t *smb2_dyn;
  36         size_t len = 4 + SMB2_HDR_BODY + 0x24 + 2;
  37
  38         smb2_inbuf = talloc_zero_array(talloc_tos(), uint8_t, len);
  39         if (smb2_inbuf == NULL) {
  40                 DEBUG(0, ("Could not push spnego blob\n"));
  41                 reply_nterror(req, NT_STATUS_NO_MEMORY);
  42                 return;
  43         }
  44         smb2_hdr = smb2_inbuf + 4;
  45         smb2_body = smb2_hdr + SMB2_HDR_BODY;
  46         smb2_dyn = smb2_body + 0x24;
  47
  48         SIVAL(smb2_hdr, SMB2_HDR_PROTOCOL_ID,   SMB2_MAGIC);
  49         SIVAL(smb2_hdr, SMB2_HDR_LENGTH,        SMB2_HDR_BODY);
  50
  51         SSVAL(smb2_body, 0x00, 0x0024); /* struct size */
  52         SSVAL(smb2_body, 0x02, 0x0001); /* dialect count */
  53
  54         SSVAL(smb2_dyn,  0x00, 0x0202); /* dialect 2.002 */
  55
  56         req->outbuf = NULL;
  57
  58         smbd_smb2_first_negprot(req->sconn, smb2_inbuf, len);
  59         return;
  60 }
  61
  62 NTSTATUS smbd_smb2_request_process_negprot(struct smbd_smb2_request *req)
  63 {
  64         NTSTATUS status;
  65         const uint8_t *inbody;
  66         const uint8_t *indyn = NULL;
  67         int i = req->current_idx;
  68         DATA_BLOB outbody;
  69         DATA_BLOB outdyn;
  70         DATA_BLOB negprot_spnego_blob;
  71         uint16_t security_offset;
  72         DATA_BLOB security_buffer;
  73         size_t expected_dyn_size = 0;
  74         size_t c;
  75         uint16_t security_mode;
  76         uint16_t dialect_count;
  77         uint16_t dialect = 0;
  78         uint32_t capabilities;
  79         uint32_t max_limit;
  80         uint32_t max_trans = lp_smb2_max_trans();
  81         uint32_t max_read = lp_smb2_max_read();
  82         uint32_t max_write = lp_smb2_max_write();
  83
  84 /* TODO: drop the connection with INVALID_PARAMETER */
  85
  86         status = smbd_smb2_request_verify_sizes(req, 0x24);
  87         if (!NT_STATUS_IS_OK(status)) {
  88                 return smbd_smb2_request_error(req, status);
  89         }
  90         inbody = (const uint8_t *)req->in.vector[i+1].iov_base;
  91
  92         dialect_count = SVAL(inbody, 0x02);
  93         if (dialect_count == 0) {
  94                 return smbd_smb2_request_error(req, NT_STATUS_INVALID_PARAMETER);
  95         }
  96
  97         expected_dyn_size = dialect_count * 2;
  98         if (req->in.vector[i+2].iov_len < expected_dyn_size) {
  99                 return smbd_smb2_request_error(req, NT_STATUS_INVALID_PARAMETER);
 100         }
 101         indyn = (const uint8_t *)req->in.vector[i+2].iov_base;
 102
 103         for (c=0; c < dialect_count; c++) {
 104                 dialect = SVAL(indyn, c*2);
 105                 if (dialect == SMB2_DIALECT_REVISION_202) {
 106                         break;
 107                 }
 108         }
 109
 110         if (dialect != SMB2_DIALECT_REVISION_202) {
 111                 return smbd_smb2_request_error(req, NT_STATUS_INVALID_PARAMETER);
 112         }
 113
 114         set_Protocol(PROTOCOL_SMB2);
 115
 116         if (get_remote_arch() != RA_SAMBA) {
 117                 set_remote_arch(RA_VISTA);
 118         }
 119
 120         /* negprot_spnego() returns a the server guid in the first 16 bytes */
 121         negprot_spnego_blob = negprot_spnego(req, req->sconn);
 122         if (negprot_spnego_blob.data == NULL) {
 123                 return smbd_smb2_request_error(req, NT_STATUS_NO_MEMORY);
 124         }
 125
 126         if (negprot_spnego_blob.length < 16) {
 127                 return smbd_smb2_request_error(req, NT_STATUS_INTERNAL_ERROR);
 128         }
 129
 130         security_mode = SMB2_NEGOTIATE_SIGNING_ENABLED;
 131         if (lp_server_signing() == Required) {
 132                 security_mode |= SMB2_NEGOTIATE_SIGNING_REQUIRED;
 133         }
 134
 135         capabilities = 0;
 136         if (lp_host_msdfs()) {
 137                 capabilities |= SMB2_CAP_DFS;
 138         }
 139
 140         /*
 141          * Unless we implement SMB2_CAP_LARGE_MTU,
 142          * 0x10000 (65536) is the maximum allowed message size
 143          */
 144         max_limit = 0x10000;
 145
 146         max_trans = MIN(max_limit, max_trans);
 147         max_read  = MIN(max_limit, max_read);
 148         max_write = MIN(max_limit, max_write);
 149
 150         security_offset = SMB2_HDR_BODY + 0x40;
 151
 152 #if 1
 153         /* Try SPNEGO auth... */
 154         security_buffer = data_blob_const(negprot_spnego_blob.data + 16,
 155                                           negprot_spnego_blob.length - 16);
 156 #else
 157         /* for now we want raw NTLMSSP */
 158         security_buffer = data_blob_const(NULL, 0);
 159 #endif
 160
 161         outbody = data_blob_talloc(req->out.vector, NULL, 0x40);
 162         if (outbody.data == NULL) {
 163                 return smbd_smb2_request_error(req, NT_STATUS_NO_MEMORY);
 164         }
 165
 166         SSVAL(outbody.data, 0x00, 0x40 + 1);    /* struct size */
 167         SSVAL(outbody.data, 0x02,
 168               security_mode);                   /* security mode */
 169         SSVAL(outbody.data, 0x04, dialect);     /* dialect revision */
 170         SSVAL(outbody.data, 0x06, 0);           /* reserved */
 171         memcpy(outbody.data + 0x08,
 172                negprot_spnego_blob.data, 16);   /* server guid */
 173         SIVAL(outbody.data, 0x18,
 174               capabilities);                    /* capabilities */
 175         SIVAL(outbody.data, 0x1C, max_trans);   /* max transact size */
 176         SIVAL(outbody.data, 0x20, max_trans);   /* max read size */
 177         SIVAL(outbody.data, 0x24, max_trans);   /* max write size */
 178         SBVAL(outbody.data, 0x28, 0);           /* system time */
 179         SBVAL(outbody.data, 0x30, 0);           /* server start time */
 180         SSVAL(outbody.data, 0x38,
 181               security_offset);                 /* security buffer offset */
 182         SSVAL(outbody.data, 0x3A,
 183               security_buffer.length);          /* security buffer length */
 184         SIVAL(outbody.data, 0x3C, 0);           /* reserved */
 185
 186         outdyn = security_buffer;
 187
 188         req->sconn->using_smb2 = true;
 189
 190         return smbd_smb2_request_done(req, outbody, &outdyn);
 191 }