source4/smb_server/smb2/negprot.c

   1 /*
   2    Unix SMB2 implementation.
   3
   4    Copyright (C) Andrew Bartlett        2001-2005
   5    Copyright (C) Stefan Metzmacher      2005
   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 "auth/credentials/credentials.h"
  23 #include "auth/gensec/gensec.h"
  24 #include "libcli/raw/libcliraw.h"
  25 #include "libcli/raw/raw_proto.h"
  26 #include "libcli/smb2/smb2.h"
  27 #include "libcli/smb2/smb2_calls.h"
  28 #include "smb_server/smb_server.h"
  29 #include "smb_server/service_smb_proto.h"
  30 #include "smb_server/smb2/smb2_server.h"
  31 #include "smbd/service_stream.h"
  32 #include "param/param.h"
  33 #include "librpc/ndr/libndr.h"
  34
  35 static NTSTATUS smb2srv_negprot_secblob(struct smb2srv_request *req, DATA_BLOB *_blob)
  36 {
  37         struct gensec_security *gensec_security;
  38         DATA_BLOB null_data_blob = data_blob(NULL, 0);
  39         DATA_BLOB blob;
  40         NTSTATUS nt_status;
  41         struct cli_credentials *server_credentials;
  42
  43         nt_status = gensec_server_start(req,
  44                                         req->smb_conn->connection->event.ctx,
  45                                         req->smb_conn->lp_ctx,
  46                                         req->smb_conn->connection->msg_ctx,
  47                                         &gensec_security);
  48         if (!NT_STATUS_IS_OK(nt_status)) {
  49                 DEBUG(0, ("Failed to start GENSEC: %s\n", nt_errstr(nt_status)));
  50                 smbsrv_terminate_connection(req->smb_conn, "Failed to start GENSEC\n");
  51                 return nt_status;
  52         }
  53
  54         server_credentials = cli_credentials_init(req);
  55         if (!server_credentials) {
  56                 smbsrv_terminate_connection(req->smb_conn, "Failed to init server credentials\n");
  57                 return NT_STATUS_NO_MEMORY;
  58         }
  59
  60         cli_credentials_set_conf(server_credentials, req->smb_conn->lp_ctx);
  61         nt_status = cli_credentials_set_machine_account(server_credentials, req->smb_conn->lp_ctx);
  62         if (!NT_STATUS_IS_OK(nt_status)) {
  63                 DEBUG(10, ("Failed to obtain server credentials, perhaps a standalone server?: %s\n", nt_errstr(nt_status)));
  64                 talloc_free(server_credentials);
  65                 server_credentials = NULL;
  66         }
  67
  68         req->smb_conn->negotiate.server_credentials = talloc_steal(req->smb_conn, server_credentials);
  69
  70         gensec_set_target_service(gensec_security, "cifs");
  71
  72         gensec_set_credentials(gensec_security, server_credentials);
  73
  74         nt_status = gensec_start_mech_by_oid(gensec_security, GENSEC_OID_SPNEGO);
  75         if (!NT_STATUS_IS_OK(nt_status)) {
  76                 DEBUG(0, ("Failed to start SPNEGO: %s\n", nt_errstr(nt_status)));
  77                 smbsrv_terminate_connection(req->smb_conn, "Failed to start SPNEGO\n");
  78                 return nt_status;
  79         }
  80
  81         nt_status = gensec_update(gensec_security, req, null_data_blob, &blob);
  82         if (!NT_STATUS_IS_OK(nt_status) && !NT_STATUS_EQUAL(nt_status, NT_STATUS_MORE_PROCESSING_REQUIRED)) {
  83                 DEBUG(0, ("Failed to get SPNEGO to give us the first token: %s\n", nt_errstr(nt_status)));
  84                 smbsrv_terminate_connection(req->smb_conn, "Failed to start SPNEGO - no first token\n");
  85                 return nt_status;
  86         }
  87
  88         *_blob = blob;
  89         return NT_STATUS_OK;
  90 }
  91
  92 static NTSTATUS smb2srv_negprot_backend(struct smb2srv_request *req, struct smb2_negprot *io)
  93 {
  94         NTSTATUS status;
  95         struct timeval current_time;
  96         struct timeval boot_time;
  97
  98         /* we only do one dialect for now */
  99         if (io->in.dialect_count < 1) {
 100                 return NT_STATUS_NOT_SUPPORTED;
 101         }
 102         if (io->in.dialects[0] != 0 &&
 103             io->in.dialects[0] != SMB2_DIALECT_REVISION) {
 104                 DEBUG(0,("Got unexpected SMB2 dialect %u\n", io->in.dialects[0]));
 105                 return NT_STATUS_NOT_SUPPORTED;
 106         }
 107
 108         req->smb_conn->negotiate.protocol = PROTOCOL_SMB2;
 109
 110         current_time = timeval_current(); /* TODO: handle timezone?! */
 111         boot_time = timeval_current(); /* TODO: fix me */
 112
 113         ZERO_STRUCT(io->out);
 114         switch (lp_server_signing(req->smb_conn->lp_ctx)) {
 115         case SMB_SIGNING_OFF:
 116                 io->out.security_mode = 0;
 117                 break;
 118         case SMB_SIGNING_SUPPORTED:
 119         case SMB_SIGNING_AUTO:
 120                 io->out.security_mode = SMB2_NEGOTIATE_SIGNING_ENABLED;
 121                 break;
 122         case SMB_SIGNING_REQUIRED:
 123                 io->out.security_mode = SMB2_NEGOTIATE_SIGNING_ENABLED | SMB2_NEGOTIATE_SIGNING_REQUIRED;
 124                 /* force signing on immediately */
 125                 req->smb_conn->smb2_signing_required = true;
 126                 break;
 127         }
 128         io->out.dialect_revision   = SMB2_DIALECT_REVISION;
 129         io->out.capabilities       = 0;
 130         io->out.max_transact_size  = lp_parm_ulong(req->smb_conn->lp_ctx, NULL,
 131                                                    "smb2", "max transaction size", 0x10000);
 132         io->out.max_read_size      = lp_parm_ulong(req->smb_conn->lp_ctx, NULL,
 133                                                    "smb2", "max read size", 0x10000);
 134         io->out.max_write_size     = lp_parm_ulong(req->smb_conn->lp_ctx, NULL,
 135                                                    "smb2", "max write size", 0x10000);
 136         io->out.system_time        = timeval_to_nttime(&current_time);
 137         io->out.server_start_time  = timeval_to_nttime(&boot_time);
 138         io->out.reserved2          = 0;
 139         status = smb2srv_negprot_secblob(req, &io->out.secblob);
 140         NT_STATUS_NOT_OK_RETURN(status);
 141
 142         return NT_STATUS_OK;
 143 }
 144
 145 static void smb2srv_negprot_send(struct smb2srv_request *req, struct smb2_negprot *io)
 146 {
 147         NTSTATUS status;
 148         enum ndr_err_code ndr_err;
 149
 150         if (NT_STATUS_IS_ERR(req->status)) {
 151                 smb2srv_send_error(req, req->status); /* TODO: is this correct? */
 152                 return;
 153         }
 154
 155         status = smb2srv_setup_reply(req, 0x40, true, io->out.secblob.length);
 156         if (!NT_STATUS_IS_OK(status)) {
 157                 smbsrv_terminate_connection(req->smb_conn, nt_errstr(status));
 158                 talloc_free(req);
 159                 return;
 160         }
 161
 162         SSVAL(req->out.body, 0x02, io->out.security_mode);
 163         SIVAL(req->out.body, 0x04, io->out.dialect_revision);
 164         SIVAL(req->out.body, 0x06, io->out.reserved);
 165         ndr_err = smbcli_push_guid(req->out.body, 0x08, &io->out.server_guid);
 166         if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 167                 smbsrv_terminate_connection(req->smb_conn, nt_errstr(status));
 168                 talloc_free(req);
 169                 return;
 170         }
 171         SIVAL(req->out.body, 0x18, io->out.capabilities);
 172         SIVAL(req->out.body, 0x1C, io->out.max_transact_size);
 173         SIVAL(req->out.body, 0x20, io->out.max_read_size);
 174         SIVAL(req->out.body, 0x24, io->out.max_write_size);
 175         push_nttime(req->out.body, 0x28, io->out.system_time);
 176         push_nttime(req->out.body, 0x30, io->out.server_start_time);
 177         SIVAL(req->out.body, 0x3C, io->out.reserved2);
 178         status = smb2_push_o16s16_blob(&req->out, 0x38, io->out.secblob);
 179         if (!NT_STATUS_IS_OK(status)) {
 180                 smbsrv_terminate_connection(req->smb_conn, nt_errstr(status));
 181                 talloc_free(req);
 182                 return;
 183         }
 184
 185         smb2srv_send_reply(req);
 186 }
 187
 188 void smb2srv_negprot_recv(struct smb2srv_request *req)
 189 {
 190         struct smb2_negprot *io;
 191         int i;
 192         enum ndr_err_code ndr_err;
 193
 194         if (req->in.body_size < 0x26) {
 195                 smb2srv_send_error(req,  NT_STATUS_FOOBAR);
 196                 return;
 197         }
 198
 199         io = talloc(req, struct smb2_negprot);
 200         if (!io) {
 201                 smbsrv_terminate_connection(req->smb_conn, nt_errstr(NT_STATUS_NO_MEMORY));
 202                 talloc_free(req);
 203                 return;
 204         }
 205
 206         io->in.dialect_count = SVAL(req->in.body, 0x02);
 207         io->in.security_mode = SVAL(req->in.body, 0x04);
 208         io->in.reserved      = SVAL(req->in.body, 0x06);
 209         io->in.capabilities  = IVAL(req->in.body, 0x08);
 210         ndr_err = smbcli_pull_guid(req->in.body, 0xC, &io->in.client_guid);
 211         if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 212                 smbsrv_terminate_connection(req->smb_conn, nt_errstr(NT_STATUS_FOOBAR));
 213                 talloc_free(req);
 214                 return;
 215         }
 216         io->in.start_time = smbcli_pull_nttime(req->in.body, 0x1C);
 217
 218         io->in.dialects = talloc_array(req, uint16_t, io->in.dialect_count);
 219         if (io->in.dialects == NULL) {
 220                 smbsrv_terminate_connection(req->smb_conn, nt_errstr(NT_STATUS_NO_MEMORY));
 221                 talloc_free(req);
 222                 return;
 223         }
 224         for (i=0;i<io->in.dialect_count;i++) {
 225                 io->in.dialects[i] = SVAL(req->in.body, 0x24+i*2);
 226         }
 227
 228         req->status = smb2srv_negprot_backend(req, io);
 229
 230         if (req->control_flags & SMB2SRV_REQ_CTRL_FLAG_NOT_REPLY) {
 231                 talloc_free(req);
 232                 return;
 233         }
 234         smb2srv_negprot_send(req, io);
 235 }
 236
 237 /*
 238  * reply to a SMB negprot request with dialect "SMB 2.002"
 239  */
 240 void smb2srv_reply_smb_negprot(struct smbsrv_request *smb_req)
 241 {
 242         struct smb2srv_request *req;
 243         uint32_t body_fixed_size = 0x26;
 244
 245         req = talloc_zero(smb_req->smb_conn, struct smb2srv_request);
 246         if (!req) goto nomem;
 247         req->smb_conn           = smb_req->smb_conn;
 248         req->request_time       = smb_req->request_time;
 249         talloc_steal(req, smb_req);
 250
 251         req->in.size      = NBT_HDR_SIZE+SMB2_HDR_BODY+body_fixed_size;
 252         req->in.allocated = req->in.size;
 253         req->in.buffer    = talloc_array(req, uint8_t, req->in.allocated);
 254         if (!req->in.buffer) goto nomem;
 255         req->in.hdr       = req->in.buffer + NBT_HDR_SIZE;
 256         req->in.body      = req->in.hdr + SMB2_HDR_BODY;
 257         req->in.body_size = body_fixed_size;
 258         req->in.dynamic   = NULL;
 259
 260         smb2srv_setup_bufinfo(req);
 261
 262         SIVAL(req->in.hdr, 0,                           SMB2_MAGIC);
 263         SSVAL(req->in.hdr, SMB2_HDR_LENGTH,             SMB2_HDR_BODY);
 264         SSVAL(req->in.hdr, SMB2_HDR_EPOCH,              0);
 265         SIVAL(req->in.hdr, SMB2_HDR_STATUS,             0);
 266         SSVAL(req->in.hdr, SMB2_HDR_OPCODE,             SMB2_OP_NEGPROT);
 267         SSVAL(req->in.hdr, SMB2_HDR_CREDIT,             0);
 268         SIVAL(req->in.hdr, SMB2_HDR_FLAGS,              0);
 269         SIVAL(req->in.hdr, SMB2_HDR_NEXT_COMMAND,       0);
 270         SBVAL(req->in.hdr, SMB2_HDR_MESSAGE_ID,         0);
 271         SIVAL(req->in.hdr, SMB2_HDR_PID,                0);
 272         SIVAL(req->in.hdr, SMB2_HDR_TID,                0);
 273         SBVAL(req->in.hdr, SMB2_HDR_SESSION_ID,         0);
 274         memset(req->in.hdr+SMB2_HDR_SIGNATURE, 0, 16);
 275
 276         /* this seems to be a bug, they use 0x24 but the length is 0x26 */
 277         SSVAL(req->in.body, 0x00, 0x24);
 278
 279         SSVAL(req->in.body, 0x02, 1);
 280         memset(req->in.body+0x04, 0, 32);
 281         SSVAL(req->in.body, 0x24, 0);
 282
 283         smb2srv_negprot_recv(req);
 284         return;
 285 nomem:
 286         smbsrv_terminate_connection(smb_req->smb_conn, nt_errstr(NT_STATUS_NO_MEMORY));
 287         talloc_free(req);
 288         return;
 289 }