source3/rpc_server/dcesrv_spnego.c

   1 /*
   2  *  SPNEGO Encapsulation
   3  *  DCERPC Server functions
   4  *  Copyright (C) Simo Sorce 2010.
   5  *
   6  *  This program is free software; you can redistribute it and/or modify
   7  *  it under the terms of the GNU General Public License as published by
   8  *  the Free Software Foundation; either version 3 of the License, or
   9  *  (at your option) any later version.
  10  *
  11  *  This program is distributed in the hope that it will be useful,
  12  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  *  GNU General Public License for more details.
  15  *
  16  *  You should have received a copy of the GNU General Public License
  17  *  along with this program; if not, see <http://www.gnu.org/licenses/>.
  18  */
  19
  20 #include "includes.h"
  21 #include "../libcli/auth/spnego.h"
  22 #include "../lib/tsocket/tsocket.h"
  23 #include "dcesrv_ntlmssp.h"
  24 #include "dcesrv_gssapi.h"
  25 #include "dcesrv_spnego.h"
  26
  27 static NTSTATUS spnego_init_server(TALLOC_CTX *mem_ctx,
  28                                    bool do_sign, bool do_seal,
  29                                    bool is_dcerpc,
  30                                    const struct tsocket_address *remote_address,
  31                                    struct spnego_context **spnego_ctx)
  32 {
  33         struct spnego_context *sp_ctx = NULL;
  34
  35         sp_ctx = talloc_zero(mem_ctx, struct spnego_context);
  36         if (!sp_ctx) {
  37                 return NT_STATUS_NO_MEMORY;
  38         }
  39
  40         sp_ctx->remote_address = tsocket_address_copy(remote_address, sp_ctx);
  41         if (sp_ctx->remote_address == NULL) {
  42                 return NT_STATUS_NO_MEMORY;
  43         }
  44
  45         sp_ctx->do_sign = do_sign;
  46         sp_ctx->do_seal = do_seal;
  47         sp_ctx->is_dcerpc = is_dcerpc;
  48
  49         *spnego_ctx = sp_ctx;
  50         return NT_STATUS_OK;
  51 }
  52
  53 static NTSTATUS spnego_server_mech_init(struct spnego_context *sp_ctx,
  54                                         DATA_BLOB *token_in,
  55                                         DATA_BLOB *token_out)
  56 {
  57         struct gensec_security *gensec_security;
  58         struct gse_context *gse_ctx;
  59         NTSTATUS status;
  60
  61         switch (sp_ctx->mech) {
  62         case SPNEGO_KRB5:
  63                 status = gssapi_server_auth_start(sp_ctx,
  64                                                   sp_ctx->do_sign,
  65                                                   sp_ctx->do_seal,
  66                                                   sp_ctx->is_dcerpc,
  67                                                   token_in,
  68                                                   token_out,
  69                                                   &gse_ctx);
  70                 if (!NT_STATUS_IS_OK(status)) {
  71                         DEBUG(0, ("Failed to init gssapi server "
  72                                   "(%s)\n", nt_errstr(status)));
  73                         return status;
  74                 }
  75
  76                 sp_ctx->mech_ctx.gssapi_state = gse_ctx;
  77                 break;
  78
  79         case SPNEGO_NTLMSSP:
  80                 status = ntlmssp_server_auth_start(sp_ctx,
  81                                                    sp_ctx->do_sign,
  82                                                    sp_ctx->do_seal,
  83                                                    sp_ctx->is_dcerpc,
  84                                                    token_in,
  85                                                    token_out,
  86                                                    sp_ctx->remote_address,
  87                                                    &gensec_security);
  88                 if (!NT_STATUS_IS_OK(status)) {
  89                         DEBUG(0, ("Failed to init ntlmssp server "
  90                                   "(%s)\n", nt_errstr(status)));
  91                         return status;
  92                 }
  93
  94                 sp_ctx->mech_ctx.gensec_security = gensec_security;
  95                 break;
  96
  97         default:
  98                 DEBUG(3, ("No known mechanisms available\n"));
  99                 return NT_STATUS_INVALID_PARAMETER;
 100         }
 101
 102         return NT_STATUS_OK;
 103 }
 104
 105 NTSTATUS spnego_server_step(struct spnego_context *sp_ctx,
 106                             TALLOC_CTX *mem_ctx,
 107                             DATA_BLOB *spnego_in,
 108                             DATA_BLOB *spnego_out)
 109 {
 110         DATA_BLOB token_in = data_blob_null;
 111         DATA_BLOB token_out = data_blob_null;
 112         DATA_BLOB signature = data_blob_null;
 113         DATA_BLOB MICblob = data_blob_null;
 114         struct spnego_data sp_in;
 115         ssize_t len_in = 0;
 116         NTSTATUS status;
 117         bool ret;
 118
 119         len_in = spnego_read_data(mem_ctx, *spnego_in, &sp_in);
 120         if (len_in == -1) {
 121                 DEBUG(1, (__location__ ": invalid SPNEGO blob.\n"));
 122                 dump_data(10, spnego_in->data, spnego_in->length);
 123                 status = NT_STATUS_INVALID_PARAMETER;
 124                 sp_ctx->state = SPNEGO_CONV_AUTH_DONE;
 125                 goto done;
 126         }
 127         if (sp_in.type != SPNEGO_NEG_TOKEN_TARG) {
 128                 status = NT_STATUS_INVALID_PARAMETER;
 129                 goto done;
 130         }
 131         token_in = sp_in.negTokenTarg.responseToken;
 132         signature = sp_in.negTokenTarg.mechListMIC;
 133
 134         switch (sp_ctx->state) {
 135         case SPNEGO_CONV_NEGO:
 136                 /* still to initialize */
 137                 status = spnego_server_mech_init(sp_ctx,
 138                                                  &token_in,
 139                                                  &token_out);
 140                 if (!NT_STATUS_IS_OK(status)) {
 141                         goto done;
 142                 }
 143                 /* server always need at least one reply from client */
 144                 status = NT_STATUS_MORE_PROCESSING_REQUIRED;
 145                 sp_ctx->state = SPNEGO_CONV_AUTH_MORE;
 146                 break;
 147
 148         case SPNEGO_CONV_AUTH_MORE:
 149
 150                 switch(sp_ctx->mech) {
 151                 case SPNEGO_KRB5:
 152                         status = gssapi_server_step(
 153                                         sp_ctx->mech_ctx.gssapi_state,
 154                                         mem_ctx, &token_in, &token_out);
 155                         break;
 156                 case SPNEGO_NTLMSSP:
 157                         status = ntlmssp_server_step(
 158                                         sp_ctx->mech_ctx.gensec_security,
 159                                         mem_ctx, &token_in, &token_out);
 160                         break;
 161                 default:
 162                         status = NT_STATUS_INVALID_PARAMETER;
 163                         goto done;
 164                 }
 165
 166                 break;
 167
 168         case SPNEGO_CONV_AUTH_DONE:
 169                 /* we are already done, can't step further */
 170                 /* fall thorugh and return error */
 171         default:
 172                 /* wrong case */
 173                 return NT_STATUS_INVALID_PARAMETER;
 174         }
 175
 176         if (NT_STATUS_IS_OK(status) && signature.length != 0) {
 177                 /* last packet and requires signature check */
 178                 ret = spnego_mech_list_blob(talloc_tos(),
 179                                             sp_ctx->oid_list, &MICblob);
 180                 if (ret) {
 181                         status = spnego_sigcheck(talloc_tos(), sp_ctx,
 182                                                  &MICblob, &MICblob,
 183                                                  &signature);
 184                 } else {
 185                         status = NT_STATUS_UNSUCCESSFUL;
 186                 }
 187         }
 188         if (NT_STATUS_IS_OK(status) && signature.length != 0) {
 189                 /* if signature was good, sign our own packet too */
 190                 status = spnego_sign(talloc_tos(), sp_ctx,
 191                                      &MICblob, &MICblob, &signature);
 192         }
 193
 194 done:
 195         *spnego_out = spnego_gen_auth_response_and_mic(mem_ctx, status,
 196                                                         sp_ctx->mech_oid,
 197                                                         &token_out,
 198                                                         &signature);
 199         if (!spnego_out->data) {
 200                 DEBUG(1, ("SPNEGO wrapping failed!\n"));
 201                 status = NT_STATUS_UNSUCCESSFUL;
 202         }
 203
 204         if (NT_STATUS_IS_OK(status) ||
 205             !NT_STATUS_EQUAL(status,
 206                         NT_STATUS_MORE_PROCESSING_REQUIRED)) {
 207                 sp_ctx->state = SPNEGO_CONV_AUTH_DONE;
 208         }
 209
 210         data_blob_free(&token_in);
 211         data_blob_free(&token_out);
 212         return status;
 213 }
 214
 215 NTSTATUS spnego_server_auth_start(TALLOC_CTX *mem_ctx,
 216                                   bool do_sign,
 217                                   bool do_seal,
 218                                   bool is_dcerpc,
 219                                   DATA_BLOB *spnego_in,
 220                                   DATA_BLOB *spnego_out,
 221                                   const struct tsocket_address *remote_address,
 222                                   struct spnego_context **spnego_ctx)
 223 {
 224         struct spnego_context *sp_ctx;
 225         DATA_BLOB token_in = data_blob_null;
 226         DATA_BLOB token_out = data_blob_null;
 227         unsigned int i;
 228         NTSTATUS status;
 229         bool ret;
 230
 231         if (!spnego_in->length) {
 232                 return NT_STATUS_INVALID_PARAMETER;
 233         }
 234
 235         status = spnego_init_server(mem_ctx,
 236                                     do_sign,
 237                                     do_seal,
 238                                     is_dcerpc,
 239                                     remote_address,
 240                                     &sp_ctx);
 241         if (!NT_STATUS_IS_OK(status)) {
 242                 return status;
 243         }
 244
 245         ret = spnego_parse_negTokenInit(sp_ctx, *spnego_in,
 246                                         sp_ctx->oid_list, NULL, &token_in);
 247         if (!ret || sp_ctx->oid_list[0] == NULL) {
 248                 DEBUG(3, ("Invalid SPNEGO message\n"));
 249                 status = NT_STATUS_INVALID_PARAMETER;
 250                 goto done;
 251         }
 252
 253         /* try for krb auth first */
 254         for (i = 0; sp_ctx->oid_list[i] && sp_ctx->mech == SPNEGO_NONE; i++) {
 255                 if (strcmp(OID_KERBEROS5, sp_ctx->oid_list[i]) == 0 ||
 256                     strcmp(OID_KERBEROS5_OLD, sp_ctx->oid_list[i]) == 0) {
 257
 258                         if (lp_security() == SEC_ADS || USE_KERBEROS_KEYTAB) {
 259                                 sp_ctx->mech = SPNEGO_KRB5;
 260                                 sp_ctx->mech_oid = sp_ctx->oid_list[i];
 261                         }
 262                 }
 263         }
 264
 265         /* if auth type still undetermined, try for NTLMSSP */
 266         for (i = 0; sp_ctx->oid_list[i] && sp_ctx->mech == SPNEGO_NONE; i++) {
 267                 if (strcmp(OID_NTLMSSP, sp_ctx->oid_list[i]) == 0) {
 268                         sp_ctx->mech = SPNEGO_NTLMSSP;
 269                         sp_ctx->mech_oid = sp_ctx->oid_list[i];
 270                 }
 271         }
 272
 273         if (!sp_ctx->mech_oid) {
 274                 DEBUG(3, ("No known mechanisms available\n"));
 275                 status = NT_STATUS_INVALID_PARAMETER;
 276                 goto done;
 277         }
 278
 279         if (DEBUGLEVEL >= 10) {
 280                 DEBUG(10, ("Client Provided OIDs:\n"));
 281                 for (i = 0; sp_ctx->oid_list[i]; i++) {
 282                         DEBUG(10, ("  %d: %s\n", i, sp_ctx->oid_list[i]));
 283                 }
 284                 DEBUG(10, ("Chosen OID: %s\n", sp_ctx->mech_oid));
 285         }
 286
 287         /* If it is not the first OID, then token_in is not valid for the
 288          * choosen mech */
 289         if (sp_ctx->mech_oid != sp_ctx->oid_list[0]) {
 290                 /* request more and send back empty token */
 291                 status = NT_STATUS_MORE_PROCESSING_REQUIRED;
 292                 sp_ctx->state = SPNEGO_CONV_NEGO;
 293                 goto done;
 294         }
 295
 296         status = spnego_server_mech_init(sp_ctx, &token_in, &token_out);
 297         if (!NT_STATUS_IS_OK(status)) {
 298                 goto done;
 299         }
 300
 301         DEBUG(10, ("SPNEGO(%d) auth started\n", sp_ctx->mech));
 302
 303         /* server always need at least one reply from client */
 304         status = NT_STATUS_MORE_PROCESSING_REQUIRED;
 305         sp_ctx->state = SPNEGO_CONV_AUTH_MORE;
 306
 307 done:
 308         *spnego_out = spnego_gen_auth_response(mem_ctx, &token_out,
 309                                                 status, sp_ctx->mech_oid);
 310         if (!spnego_out->data) {
 311                 status = NT_STATUS_INVALID_PARAMETER;
 312                 TALLOC_FREE(sp_ctx);
 313         } else {
 314                 status = NT_STATUS_OK;
 315                 *spnego_ctx = sp_ctx;
 316         }
 317
 318         data_blob_free(&token_in);
 319         data_blob_free(&token_out);
 320
 321         return status;
 322 }