www.project-moonshot.org Git - mech_eap.orig/blob - accept_sec_context.c

   1 /*
   2  * Copyright (c) 2010, JANET(UK)
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  *
   9  * 1. Redistributions of source code must retain the above copyright
  10  *    notice, this list of conditions and the following disclaimer.
  11  *
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  *
  16  * 3. Neither the name of JANET(UK) nor the names of its contributors
  17  *    may be used to endorse or promote products derived from this software
  18  *    without specific prior written permission.
  19  *
  20  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
  21  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  23  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
  24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  30  * SUCH DAMAGE.
  31  */
  32
  33 #include "gssapiP_eap.h"
  34
  35 #define BUILTIN_EAP
  36
  37 #ifdef BUILTIN_EAP
  38 #define EAP_MAX_METHODS 8
  39
  40 #define EAP_TTLS_AUTH_PAP 1
  41 #define EAP_TTLS_AUTH_CHAP 2
  42 #define EAP_TTLS_AUTH_MSCHAP 4
  43 #define EAP_TTLS_AUTH_MSCHAPV2 8
  44
  45 struct eap_user {
  46         struct {
  47                 int vendor;
  48                 u32 method;
  49         } methods[EAP_MAX_METHODS];
  50         u8 *password;
  51         size_t password_len;
  52         int password_hash; /* whether password is hashed with
  53                             * nt_password_hash() */
  54         int phase2;
  55         int force_version;
  56         int ttls_auth; /* bitfield of
  57                         * EAP_TTLS_AUTH_{PAP,CHAP,MSCHAP,MSCHAPV2} */
  58 };
  59
  60 struct eap_eapol_interface {
  61         /* Lower layer to full authenticator variables */
  62         Boolean eapResp; /* shared with EAPOL Backend Authentication */
  63         struct wpabuf *eapRespData;
  64         Boolean portEnabled;
  65         int retransWhile;
  66         Boolean eapRestart; /* shared with EAPOL Authenticator PAE */
  67         int eapSRTT;
  68         int eapRTTVAR;
  69
  70         /* Full authenticator to lower layer variables */
  71         Boolean eapReq; /* shared with EAPOL Backend Authentication */
  72         Boolean eapNoReq; /* shared with EAPOL Backend Authentication */
  73         Boolean eapSuccess;
  74         Boolean eapFail;
  75         Boolean eapTimeout;
  76         struct wpabuf *eapReqData;
  77         u8 *eapKeyData;
  78         size_t eapKeyDataLen;
  79         Boolean eapKeyAvailable; /* called keyAvailable in IEEE 802.1X-2004 */
  80
  81         /* AAA interface to full authenticator variables */
  82         Boolean aaaEapReq;
  83         Boolean aaaEapNoReq;
  84         Boolean aaaSuccess;
  85         Boolean aaaFail;
  86         struct wpabuf *aaaEapReqData;
  87         u8 *aaaEapKeyData;
  88         size_t aaaEapKeyDataLen;
  89         Boolean aaaEapKeyAvailable;
  90         int aaaMethodTimeout;
  91
  92         /* Full authenticator to AAA interface variables */
  93         Boolean aaaEapResp;
  94         struct wpabuf *aaaEapRespData;
  95         /* aaaIdentity -> eap_get_identity() */
  96         Boolean aaaTimeout;
  97 };
  98
  99 #define eapol_callbacks     SERVER_eapol_callbacks
 100
 101 struct eapol_callbacks {
 102         int (*get_eap_user)(void *ctx, const u8 *identity, size_t identity_len,
 103                             int phase2, struct eap_user *user);
 104         const char * (*get_eap_req_id_text)(void *ctx, size_t *len);
 105 };
 106
 107 #define eap_config          SERVER_eap_config
 108
 109 struct eap_config {
 110         void *ssl_ctx;
 111         void *msg_ctx;
 112         void *eap_sim_db_priv;
 113         Boolean backend_auth;
 114         int eap_server;
 115         u8 *pac_opaque_encr_key;
 116         u8 *eap_fast_a_id;
 117         size_t eap_fast_a_id_len;
 118         char *eap_fast_a_id_info;
 119         int eap_fast_prov;
 120         int pac_key_lifetime;
 121         int pac_key_refresh_time;
 122         int eap_sim_aka_result_ind;
 123         int tnc;
 124         struct wps_context *wps;
 125         const struct wpabuf *assoc_wps_ie;
 126         const u8 *peer_addr;
 127         int fragment_size;
 128 };
 129
 130 struct eap_sm * eap_server_sm_init(void *eapol_ctx,
 131                                    struct eapol_callbacks *eapol_cb,
 132                                    struct eap_config *eap_conf);
 133 void eap_server_sm_deinit(struct eap_sm *sm);
 134 int eap_server_sm_step(struct eap_sm *sm);
 135 void eap_sm_notify_cached(struct eap_sm *sm);
 136 void eap_sm_pending_cb(struct eap_sm *sm);
 137 int eap_sm_method_pending(struct eap_sm *sm);
 138 const u8 * eap_get_identity(struct eap_sm *sm, size_t *len);
 139 struct eap_eapol_interface * eap_get_interface(struct eap_sm *sm);
 140
 141 #include <eap_server/eap_i.h>
 142
 143 static OM_uint32
 144 initTls(OM_uint32 *minor,
 145         gss_ctx_id_t ctx)
 146 {
 147     struct tls_config tconf;
 148     struct tls_connection_params tparams;
 149
 150     memset(&tconf, 0, sizeof(tconf));
 151     ctx->acceptorCtx.tlsContext = tls_init(&tconf);
 152     if (ctx->acceptorCtx.tlsContext == NULL)
 153         return GSS_S_FAILURE;
 154
 155     memset(&tparams, 0, sizeof(tparams));
 156     tparams.ca_cert = "ca.pem";
 157     tparams.client_cert = "server.pem";
 158     tparams.private_key = "server-key.pem";
 159
 160     if (tls_global_set_params(ctx->acceptorCtx.tlsContext, &tparams)) {
 161         return GSS_S_FAILURE;
 162     }
 163
 164     if (tls_global_set_verify(ctx->acceptorCtx.tlsContext, 0)) {
 165         return GSS_S_FAILURE;
 166     }
 167
 168     return GSS_S_COMPLETE;
 169 }
 170
 171 static int
 172 serverGetEapUser(void *ctx,
 173                  const unsigned char *identity,
 174                  size_t identityLength,
 175                  int phase2,
 176                  struct eap_user *user)
 177 {
 178     gss_ctx_id_t gssCtx = (gss_ctx_id_t)ctx;
 179     OM_uint32 major, minor;
 180     gss_buffer_desc buf;
 181
 182     memset(user, 0, sizeof(*user));
 183
 184     buf.length = identityLength;
 185     buf.value = (void *)identity;
 186
 187     if (phase2 == 0) {
 188         user->methods[0].vendor = EAP_VENDOR_IETF;
 189         user->methods[0].method = EAP_TYPE_PEAP;
 190         return 0;
 191     }
 192
 193     major = gssEapImportName(&minor, &buf, GSS_C_NT_USER_NAME,
 194                              &gssCtx->initiatorName);
 195     if (GSS_ERROR(major))
 196         return -1;
 197
 198     /*
 199      * OK, obviously there is no real security here, this is simply
 200      * for testing the token exchange; this code will be completely
 201      * replaced with libradsec once that library is available.
 202      */
 203     user->methods[0].vendor = EAP_VENDOR_IETF;
 204     user->methods[0].method = EAP_TYPE_MSCHAPV2;
 205     user->password = (unsigned char *)strdup(" ");
 206     user->password_len = 1;
 207
 208     return 0;
 209 }
 210
 211 static const char *
 212 serverGetEapReqIdText(void *ctx,
 213                       size_t *len)
 214 {
 215     *len = 0;
 216     return NULL;
 217 }
 218 #endif /* BUILTIN_EAP */
 219
 220 static OM_uint32
 221 acceptReady(OM_uint32 *minor, gss_ctx_id_t ctx)
 222 {
 223     OM_uint32 major;
 224
 225     /* Cache encryption type derived from selected mechanism OID */
 226     major = gssEapOidToEnctype(minor, ctx->mechanismUsed, &ctx->encryptionType);
 227     if (GSS_ERROR(major))
 228         return major;
 229
 230     if (ctx->encryptionType != ENCTYPE_NULL &&
 231         ctx->acceptorCtx.eapPolInterface->eapKeyAvailable) {
 232         major = gssEapDeriveRfc3961Key(minor,
 233                                        ctx->acceptorCtx.eapPolInterface->eapKeyData,
 234                                        ctx->acceptorCtx.eapPolInterface->eapKeyDataLen,
 235                                        ctx->encryptionType,
 236                                        &ctx->rfc3961Key);
 237         if (GSS_ERROR(major))
 238             return major;
 239
 240         major = rfc3961ChecksumTypeForKey(minor, &ctx->rfc3961Key,
 241                                            &ctx->checksumType);
 242         if (GSS_ERROR(major))
 243             return major;
 244     } else {
 245         /*
 246          * draft-howlett-eap-gss says that integrity/confidentialty should
 247          * always be advertised as available, but if we have no keying
 248          * material it seems confusing to the caller to advertise this.
 249          */
 250         ctx->gssFlags &= ~(GSS_C_INTEG_FLAG | GSS_C_CONF_FLAG);
 251     }
 252
 253     sequenceInit(&ctx->seqState, ctx->recvSeq,
 254                  ((ctx->gssFlags & GSS_C_REPLAY_FLAG) != 0),
 255                  ((ctx->gssFlags & GSS_C_SEQUENCE_FLAG) != 0),
 256                  TRUE);
 257
 258     return GSS_S_COMPLETE;
 259 }
 260
 261 static OM_uint32
 262 eapGssSmAcceptAuthenticate(OM_uint32 *minor,
 263                            gss_ctx_id_t ctx,
 264                            gss_cred_id_t cred,
 265                            gss_buffer_t inputToken,
 266                            gss_channel_bindings_t chanBindings,
 267                            gss_buffer_t outputToken)
 268 {
 269     OM_uint32 major;
 270     OM_uint32 tmpMinor, tmpMajor;
 271     int code;
 272     struct wpabuf respData;
 273     static struct eapol_callbacks cb = { serverGetEapUser, serverGetEapReqIdText };
 274     if (ctx->acceptorCtx.eap == NULL) {
 275         struct eap_config eapConfig;
 276
 277         major = initTls(minor, ctx);
 278         if (GSS_ERROR(major))
 279             goto cleanup;
 280
 281         memset(&eapConfig, 0, sizeof(eapConfig));
 282         eapConfig.eap_server = 1;
 283         eapConfig.ssl_ctx = ctx->acceptorCtx.tlsContext;
 284
 285         ctx->acceptorCtx.eap = eap_server_sm_init(ctx, &cb, &eapConfig);
 286         if (ctx->acceptorCtx.eap == NULL) {
 287             major = GSS_S_FAILURE;
 288             goto cleanup;
 289         }
 290
 291         ctx->acceptorCtx.eapPolInterface = eap_get_interface(ctx->acceptorCtx.eap);
 292         ctx->acceptorCtx.eapPolInterface->portEnabled = TRUE;
 293         ctx->acceptorCtx.eapPolInterface->eapRestart = TRUE;
 294     }
 295
 296     if (ctx->acceptorName == GSS_C_NO_NAME &&
 297         cred != GSS_C_NO_CREDENTIAL &&
 298         cred->name != GSS_C_NO_NAME) {
 299         major = gss_duplicate_name(minor, cred->name, &ctx->acceptorName);
 300         if (GSS_ERROR(major))
 301             goto cleanup;
 302     }
 303
 304     wpabuf_set(&respData, inputToken->value, inputToken->length);
 305     ctx->acceptorCtx.eapPolInterface->eapRespData = &respData;
 306     ctx->acceptorCtx.eapPolInterface->eapResp = TRUE;
 307
 308     code = eap_server_sm_step(ctx->acceptorCtx.eap);
 309
 310     if (ctx->acceptorCtx.eapPolInterface->eapReq) {
 311         ctx->acceptorCtx.eapPolInterface->eapReq = 0;
 312         major = GSS_S_CONTINUE_NEEDED;
 313     }
 314
 315     if (ctx->acceptorCtx.eapPolInterface->eapSuccess) {
 316         ctx->acceptorCtx.eapPolInterface->eapSuccess = 0;
 317         major = acceptReady(minor, ctx);
 318         if (GSS_ERROR(major))
 319             goto cleanup;
 320
 321         ctx->state = EAP_STATE_GSS_CHANNEL_BINDINGS;
 322         major = GSS_S_CONTINUE_NEEDED;
 323     } else if (ctx->acceptorCtx.eapPolInterface->eapFail) {
 324         ctx->acceptorCtx.eapPolInterface->eapFail = 0;
 325         major = GSS_S_FAILURE;
 326     } else if (code == 0) {
 327         major = GSS_S_FAILURE;
 328     }
 329
 330     if (ctx->acceptorCtx.eapPolInterface->eapReqData != NULL) {
 331         gss_buffer_desc buf;
 332
 333         buf.length = wpabuf_len(ctx->acceptorCtx.eapPolInterface->eapReqData);
 334         buf.value = (void *)wpabuf_head(ctx->acceptorCtx.eapPolInterface->eapReqData);
 335
 336         tmpMajor = duplicateBuffer(&tmpMinor, &buf, outputToken);
 337         if (GSS_ERROR(tmpMajor)) {
 338             major = tmpMajor;
 339             *minor = tmpMinor;
 340             goto cleanup;
 341         }
 342     }
 343
 344 cleanup:
 345     ctx->acceptorCtx.eapPolInterface->eapRespData = NULL;
 346
 347     return major;
 348 }
 349
 350 static OM_uint32
 351 eapGssSmAcceptGssChannelBindings(OM_uint32 *minor,
 352                                  gss_ctx_id_t ctx,
 353                                  gss_cred_id_t cred,
 354                                  gss_buffer_t inputToken,
 355                                  gss_channel_bindings_t chanBindings,
 356                                  gss_buffer_t outputToken)
 357 {
 358     OM_uint32 major, tmpMinor;
 359     gss_iov_buffer_desc iov[2];
 360
 361     outputToken->length = 0;
 362     outputToken->value = NULL;
 363
 364     if (chanBindings == GSS_C_NO_CHANNEL_BINDINGS) {
 365         ctx->state = EAP_STATE_ESTABLISHED;
 366         return GSS_S_COMPLETE;
 367     }
 368
 369     if (inputToken->length < 14) {
 370         return GSS_S_DEFECTIVE_TOKEN;
 371     }
 372
 373     iov[0].type = GSS_IOV_BUFFER_TYPE_DATA;
 374     iov[0].buffer.length = 0;
 375     iov[0].buffer.value = NULL;
 376
 377     if (chanBindings != GSS_C_NO_CHANNEL_BINDINGS)
 378         iov[0].buffer = chanBindings->application_data;
 379
 380     iov[1].type = GSS_IOV_BUFFER_TYPE_HEADER;
 381     iov[1].buffer.length = 16;
 382     iov[1].buffer.value = (unsigned char *)inputToken->value - 2;
 383
 384     assert(load_uint16_be(iov[1].buffer.value) == TOK_TYPE_GSS_CB);
 385
 386     iov[2].type = GSS_IOV_BUFFER_TYPE_TRAILER;
 387     iov[2].buffer.length = inputToken->length - 14;
 388     iov[2].buffer.value = (unsigned char *)inputToken->value + 14;
 389
 390     major = gssEapUnwrapOrVerifyMIC(minor, ctx, NULL, NULL,
 391                                     iov, 3, TOK_TYPE_GSS_CB);
 392     if (major == GSS_S_COMPLETE) {
 393         ctx->state = EAP_STATE_ESTABLISHED;
 394     }
 395
 396 #if 0
 397     gss_release_buffer(&tmpMinor, &iov[0].buffer);
 398 #endif
 399
 400     return major;
 401 }
 402
 403 static OM_uint32
 404 eapGssSmAcceptEstablished(OM_uint32 *minor,
 405                           gss_ctx_id_t ctx,
 406                           gss_cred_id_t cred,
 407                           gss_buffer_t inputToken,
 408                           gss_channel_bindings_t chanBindings,
 409                           gss_buffer_t outputToken)
 410 {
 411     /* Called with already established context */
 412     *minor = EINVAL;
 413     return GSS_S_BAD_STATUS;
 414 }
 415
 416 static struct eap_gss_acceptor_sm {
 417     enum gss_eap_token_type inputTokenType;
 418     enum gss_eap_token_type outputTokenType;
 419     OM_uint32 (*processToken)(OM_uint32 *,
 420                               gss_ctx_id_t,
 421                               gss_cred_id_t,
 422                               gss_buffer_t,
 423                               gss_channel_bindings_t,
 424                               gss_buffer_t);
 425 } eapGssAcceptorSm[] = {
 426     { TOK_TYPE_EAP_RESP,    TOK_TYPE_EAP_REQ,  eapGssSmAcceptAuthenticate       },
 427 #if 0
 428     { TOK_TYPE_EAP_RESP,    TOK_TYPE_EAP_REQ,  NULL                             },
 429     { TOK_TYPE_EAP_RESP,    TOK_TYPE_EAP_REQ,  NULL                             },
 430 #endif
 431     { TOK_TYPE_GSS_CB,      TOK_TYPE_NONE,     eapGssSmAcceptGssChannelBindings },
 432     { TOK_TYPE_NONE,        TOK_TYPE_NONE,     eapGssSmAcceptEstablished        },
 433 };
 434
 435 OM_uint32
 436 gss_accept_sec_context(OM_uint32 *minor,
 437                        gss_ctx_id_t *context_handle,
 438                        gss_cred_id_t cred,
 439                        gss_buffer_t input_token,
 440                        gss_channel_bindings_t input_chan_bindings,
 441                        gss_name_t *src_name,
 442                        gss_OID *mech_type,
 443                        gss_buffer_t output_token,
 444                        OM_uint32 *ret_flags,
 445                        OM_uint32 *time_rec,
 446                        gss_cred_id_t *delegated_cred_handle)
 447 {
 448     OM_uint32 major;
 449     OM_uint32 tmpMajor, tmpMinor;
 450     gss_ctx_id_t ctx = *context_handle;
 451     struct eap_gss_acceptor_sm *sm = NULL;
 452     gss_buffer_desc innerInputToken, innerOutputToken;
 453
 454     *minor = 0;
 455
 456     innerOutputToken.length = 0;
 457     innerOutputToken.value = NULL;
 458
 459     output_token->length = 0;
 460     output_token->value = NULL;
 461
 462     if (cred != GSS_C_NO_CREDENTIAL && !(cred->flags & CRED_FLAG_ACCEPT)) {
 463         return GSS_S_NO_CRED;
 464     }
 465
 466     if (input_token == GSS_C_NO_BUFFER || input_token->length == 0) {
 467         return GSS_S_DEFECTIVE_TOKEN;
 468     }
 469
 470     if (ctx == GSS_C_NO_CONTEXT) {
 471         major = gssEapAllocContext(minor, &ctx);
 472         if (GSS_ERROR(major))
 473             return major;
 474
 475         *context_handle = ctx;
 476     }
 477
 478     GSSEAP_MUTEX_LOCK(&ctx->mutex);
 479
 480     sm = &eapGssAcceptorSm[ctx->state];
 481
 482     major = gssEapVerifyToken(minor, ctx, input_token,
 483                               sm->inputTokenType, &innerInputToken);
 484     if (GSS_ERROR(major))
 485         goto cleanup;
 486
 487     /* If credentials were provided, check they're usable with this mech */
 488     if (!gssEapCredAvailable(cred, ctx->mechanismUsed)) {
 489         major = GSS_S_BAD_MECH;
 490         goto cleanup;
 491     }
 492
 493     do {
 494         sm = &eapGssAcceptorSm[ctx->state];
 495
 496         major = (sm->processToken)(minor,
 497                                    ctx,
 498                                    cred,
 499                                    &innerInputToken,
 500                                    input_chan_bindings,
 501                                    &innerOutputToken);
 502         if (GSS_ERROR(major))
 503             goto cleanup;
 504     } while (major == GSS_S_CONTINUE_NEEDED && innerOutputToken.length == 0);
 505
 506     if (mech_type != NULL) {
 507         if (!gssEapInternalizeOid(ctx->mechanismUsed, mech_type))
 508             duplicateOid(&tmpMinor, ctx->mechanismUsed, mech_type);
 509     }
 510     if (innerOutputToken.length != 0) {
 511         tmpMajor = gssEapMakeToken(&tmpMinor, ctx, &innerOutputToken,
 512                                    sm->outputTokenType, output_token);
 513         if (GSS_ERROR(tmpMajor)) {
 514             major = tmpMajor;
 515             *minor = tmpMinor;
 516             goto cleanup;
 517         }
 518     }
 519     if (ret_flags != NULL)
 520         *ret_flags = ctx->gssFlags;
 521     if (delegated_cred_handle != NULL)
 522         *delegated_cred_handle = GSS_C_NO_CREDENTIAL;
 523
 524     if (major == GSS_S_COMPLETE) {
 525         if (src_name != NULL && ctx->initiatorName != GSS_C_NO_NAME) {
 526             major = gss_duplicate_name(&tmpMinor, ctx->initiatorName, src_name);
 527             if (GSS_ERROR(major))
 528                 goto cleanup;
 529         }
 530         if (time_rec != NULL)
 531             gss_context_time(&tmpMinor, ctx, time_rec);
 532     }
 533
 534     assert(ctx->state == EAP_STATE_ESTABLISHED || major == GSS_S_CONTINUE_NEEDED);
 535
 536 cleanup:
 537     GSSEAP_MUTEX_UNLOCK(&ctx->mutex);
 538
 539     if (GSS_ERROR(major))
 540         gssEapReleaseContext(&tmpMinor, context_handle);
 541
 542     gss_release_buffer(&tmpMinor, &innerOutputToken);
 543
 544     return major;
 545 }