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 and the given dialect.
  29  */
  30 static void reply_smb20xx(struct smb_request *req, uint16_t dialect)
  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, dialect);
  55
  56         req->outbuf = NULL;
  57
  58         smbd_smb2_first_negprot(req->sconn, smb2_inbuf, len);
  59         return;
  60 }
  61
  62 /*
  63  * this is the entry point if SMB2 is selected via
  64  * the SMB negprot and the "SMB 2.002" dialect.
  65  */
  66 void reply_smb2002(struct smb_request *req, uint16_t choice)
  67 {
  68         reply_smb20xx(req, SMB2_DIALECT_REVISION_202);
  69 }
  70
  71 /*
  72  * this is the entry point if SMB2 is selected via
  73  * the SMB negprot and the "SMB 2.???" dialect.
  74  */
  75 void reply_smb20ff(struct smb_request *req, uint16_t choice)
  76 {
  77         req->sconn->smb2.negprot_2ff = true;
  78         reply_smb20xx(req, SMB2_DIALECT_REVISION_2FF);
  79 }
  80
  81 NTSTATUS smbd_smb2_request_process_negprot(struct smbd_smb2_request *req)
  82 {
  83         NTSTATUS status;
  84         const uint8_t *inbody;
  85         const uint8_t *indyn = NULL;
  86         int i = req->current_idx;
  87         DATA_BLOB outbody;
  88         DATA_BLOB outdyn;
  89         DATA_BLOB negprot_spnego_blob;
  90         uint16_t security_offset;
  91         DATA_BLOB security_buffer;
  92         size_t expected_dyn_size = 0;
  93         size_t c;
  94         uint16_t security_mode;
  95         uint16_t dialect_count;
  96         uint16_t dialect = 0;
  97         uint32_t capabilities;
  98         enum protocol_types protocol = PROTOCOL_NONE;
  99         uint32_t max_limit;
 100         uint32_t max_trans = lp_smb2_max_trans();
 101         uint32_t max_read = lp_smb2_max_read();
 102         uint32_t max_write = lp_smb2_max_write();
 103
 104         status = smbd_smb2_request_verify_sizes(req, 0x24);
 105         if (!NT_STATUS_IS_OK(status)) {
 106                 return smbd_smb2_request_error(req, status);
 107         }
 108         inbody = (const uint8_t *)req->in.vector[i+1].iov_base;
 109
 110         dialect_count = SVAL(inbody, 0x02);
 111         if (dialect_count == 0) {
 112                 return smbd_smb2_request_error(req, NT_STATUS_INVALID_PARAMETER);
 113         }
 114
 115         expected_dyn_size = dialect_count * 2;
 116         if (req->in.vector[i+2].iov_len < expected_dyn_size) {
 117                 return smbd_smb2_request_error(req, NT_STATUS_INVALID_PARAMETER);
 118         }
 119         indyn = (const uint8_t *)req->in.vector[i+2].iov_base;
 120
 121         for (c=0; protocol == PROTOCOL_NONE && c < dialect_count; c++) {
 122                 if (lp_maxprotocol() < PROTOCOL_SMB2_24) {
 123                         break;
 124                 }
 125                 if (lp_minprotocol() > PROTOCOL_SMB2_24) {
 126                         break;
 127                 }
 128
 129                 dialect = SVAL(indyn, c*2);
 130                 if (dialect == SMB2_DIALECT_REVISION_224) {
 131                         protocol = PROTOCOL_SMB2_24;
 132                         break;
 133                 }
 134         }
 135
 136         for (c=0; protocol == PROTOCOL_NONE && c < dialect_count; c++) {
 137                 if (lp_maxprotocol() < PROTOCOL_SMB2_22) {
 138                         break;
 139                 }
 140                 if (lp_minprotocol() > PROTOCOL_SMB2_22) {
 141                         break;
 142                 }
 143
 144                 dialect = SVAL(indyn, c*2);
 145                 if (dialect == SMB2_DIALECT_REVISION_222) {
 146                         protocol = PROTOCOL_SMB2_22;
 147                         break;
 148                 }
 149         }
 150
 151         for (c=0; protocol == PROTOCOL_NONE && c < dialect_count; c++) {
 152                 if (lp_maxprotocol() < PROTOCOL_SMB2_10) {
 153                         break;
 154                 }
 155                 if (lp_minprotocol() > PROTOCOL_SMB2_10) {
 156                         break;
 157                 }
 158
 159                 dialect = SVAL(indyn, c*2);
 160                 if (dialect == SMB2_DIALECT_REVISION_210) {
 161                         protocol = PROTOCOL_SMB2_10;
 162                         break;
 163                 }
 164         }
 165
 166         for (c=0; protocol == PROTOCOL_NONE && c < dialect_count; c++) {
 167                 if (lp_maxprotocol() < PROTOCOL_SMB2_02) {
 168                         break;
 169                 }
 170                 if (lp_minprotocol() > PROTOCOL_SMB2_02) {
 171                         break;
 172                 }
 173
 174                 dialect = SVAL(indyn, c*2);
 175                 if (dialect == SMB2_DIALECT_REVISION_202) {
 176                         protocol = PROTOCOL_SMB2_02;
 177                         break;
 178                 }
 179         }
 180
 181         for (c=0; protocol == PROTOCOL_NONE && c < dialect_count; c++) {
 182                 if (lp_maxprotocol() < PROTOCOL_SMB2_10) {
 183                         break;
 184                 }
 185
 186                 dialect = SVAL(indyn, c*2);
 187                 if (dialect == SMB2_DIALECT_REVISION_2FF) {
 188                         if (req->sconn->smb2.negprot_2ff) {
 189                                 req->sconn->smb2.negprot_2ff = false;
 190                                 protocol = PROTOCOL_SMB2_10;
 191                                 break;
 192                         }
 193                 }
 194         }
 195
 196         if (protocol == PROTOCOL_NONE) {
 197                 return smbd_smb2_request_error(req, NT_STATUS_NOT_SUPPORTED);
 198         }
 199
 200         if (dialect != SMB2_DIALECT_REVISION_2FF) {
 201                 set_Protocol(protocol);
 202         }
 203
 204         if (get_remote_arch() != RA_SAMBA) {
 205                 set_remote_arch(RA_VISTA);
 206         }
 207
 208         /* negprot_spnego() returns a the server guid in the first 16 bytes */
 209         negprot_spnego_blob = negprot_spnego(req, req->sconn);
 210         if (negprot_spnego_blob.data == NULL) {
 211                 return smbd_smb2_request_error(req, NT_STATUS_NO_MEMORY);
 212         }
 213
 214         if (negprot_spnego_blob.length < 16) {
 215                 return smbd_smb2_request_error(req, NT_STATUS_INTERNAL_ERROR);
 216         }
 217
 218         security_mode = SMB2_NEGOTIATE_SIGNING_ENABLED;
 219         if (lp_server_signing() == SMB_SIGNING_REQUIRED) {
 220                 security_mode |= SMB2_NEGOTIATE_SIGNING_REQUIRED;
 221         }
 222
 223         capabilities = 0;
 224         if (lp_host_msdfs()) {
 225                 capabilities |= SMB2_CAP_DFS;
 226         }
 227
 228         /*
 229          * Unless we implement SMB2_CAP_LARGE_MTU,
 230          * 0x10000 (65536) is the maximum allowed message size
 231          */
 232         max_limit = 0x10000;
 233
 234         max_trans = MIN(max_limit, max_trans);
 235         max_read  = MIN(max_limit, max_read);
 236         max_write = MIN(max_limit, max_write);
 237
 238         security_offset = SMB2_HDR_BODY + 0x40;
 239
 240 #if 1
 241         /* Try SPNEGO auth... */
 242         security_buffer = data_blob_const(negprot_spnego_blob.data + 16,
 243                                           negprot_spnego_blob.length - 16);
 244 #else
 245         /* for now we want raw NTLMSSP */
 246         security_buffer = data_blob_const(NULL, 0);
 247 #endif
 248
 249         outbody = data_blob_talloc(req->out.vector, NULL, 0x40);
 250         if (outbody.data == NULL) {
 251                 return smbd_smb2_request_error(req, NT_STATUS_NO_MEMORY);
 252         }
 253
 254         SSVAL(outbody.data, 0x00, 0x40 + 1);    /* struct size */
 255         SSVAL(outbody.data, 0x02,
 256               security_mode);                   /* security mode */
 257         SSVAL(outbody.data, 0x04, dialect);     /* dialect revision */
 258         SSVAL(outbody.data, 0x06, 0);           /* reserved */
 259         memcpy(outbody.data + 0x08,
 260                negprot_spnego_blob.data, 16);   /* server guid */
 261         SIVAL(outbody.data, 0x18,
 262               capabilities);                    /* capabilities */
 263         SIVAL(outbody.data, 0x1C, max_trans);   /* max transact size */
 264         SIVAL(outbody.data, 0x20, max_trans);   /* max read size */
 265         SIVAL(outbody.data, 0x24, max_trans);   /* max write size */
 266         SBVAL(outbody.data, 0x28, 0);           /* system time */
 267         SBVAL(outbody.data, 0x30, 0);           /* server start time */
 268         SSVAL(outbody.data, 0x38,
 269               security_offset);                 /* security buffer offset */
 270         SSVAL(outbody.data, 0x3A,
 271               security_buffer.length);          /* security buffer length */
 272         SIVAL(outbody.data, 0x3C, 0);           /* reserved */
 273
 274         outdyn = security_buffer;
 275
 276         req->sconn->using_smb2 = true;
 277         req->sconn->smb2.max_trans = max_trans;
 278         req->sconn->smb2.max_read  = max_read;
 279         req->sconn->smb2.max_write = max_write;
 280
 281         return smbd_smb2_request_done(req, outbody, &outdyn);
 282 }