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 EAP_MAX_METHODS 8
  36
  37 #define EAP_TTLS_AUTH_PAP 1
  38 #define EAP_TTLS_AUTH_CHAP 2
  39 #define EAP_TTLS_AUTH_MSCHAP 4
  40 #define EAP_TTLS_AUTH_MSCHAPV2 8
  41
  42 #if 1
  43 struct eap_user {
  44         struct {
  45                 int vendor;
  46                 u32 method;
  47         } methods[EAP_MAX_METHODS];
  48         u8 *password;
  49         size_t password_len;
  50         int password_hash; /* whether password is hashed with
  51                             * nt_password_hash() */
  52         int phase2;
  53         int force_version;
  54         int ttls_auth; /* bitfield of
  55                         * EAP_TTLS_AUTH_{PAP,CHAP,MSCHAP,MSCHAPV2} */
  56 };
  57
  58 struct eap_eapol_interface {
  59         /* Lower layer to full authenticator variables */
  60         Boolean eapResp; /* shared with EAPOL Backend Authentication */
  61         struct wpabuf *eapRespData;
  62         Boolean portEnabled;
  63         int retransWhile;
  64         Boolean eapRestart; /* shared with EAPOL Authenticator PAE */
  65         int eapSRTT;
  66         int eapRTTVAR;
  67
  68         /* Full authenticator to lower layer variables */
  69         Boolean eapReq; /* shared with EAPOL Backend Authentication */
  70         Boolean eapNoReq; /* shared with EAPOL Backend Authentication */
  71         Boolean eapSuccess;
  72         Boolean eapFail;
  73         Boolean eapTimeout;
  74         struct wpabuf *eapReqData;
  75         u8 *eapKeyData;
  76         size_t eapKeyDataLen;
  77         Boolean eapKeyAvailable; /* called keyAvailable in IEEE 802.1X-2004 */
  78
  79         /* AAA interface to full authenticator variables */
  80         Boolean aaaEapReq;
  81         Boolean aaaEapNoReq;
  82         Boolean aaaSuccess;
  83         Boolean aaaFail;
  84         struct wpabuf *aaaEapReqData;
  85         u8 *aaaEapKeyData;
  86         size_t aaaEapKeyDataLen;
  87         Boolean aaaEapKeyAvailable;
  88         int aaaMethodTimeout;
  89
  90         /* Full authenticator to AAA interface variables */
  91         Boolean aaaEapResp;
  92         struct wpabuf *aaaEapRespData;
  93         /* aaaIdentity -> eap_get_identity() */
  94         Boolean aaaTimeout;
  95 };
  96
  97 #define eapol_callbacks     SERVER_eapol_callbacks
  98
  99 struct eapol_callbacks {
 100         int (*get_eap_user)(void *ctx, const u8 *identity, size_t identity_len,
 101                             int phase2, struct eap_user *user);
 102         const char * (*get_eap_req_id_text)(void *ctx, size_t *len);
 103 };
 104
 105 #define eap_config          SERVER_eap_config
 106
 107 struct eap_config {
 108         void *ssl_ctx;
 109         void *msg_ctx;
 110         void *eap_sim_db_priv;
 111         Boolean backend_auth;
 112         int eap_server;
 113         u8 *pac_opaque_encr_key;
 114         u8 *eap_fast_a_id;
 115         size_t eap_fast_a_id_len;
 116         char *eap_fast_a_id_info;
 117         int eap_fast_prov;
 118         int pac_key_lifetime;
 119         int pac_key_refresh_time;
 120         int eap_sim_aka_result_ind;
 121         int tnc;
 122         struct wps_context *wps;
 123         const struct wpabuf *assoc_wps_ie;
 124         const u8 *peer_addr;
 125         int fragment_size;
 126 };
 127
 128 struct eap_sm * eap_server_sm_init(void *eapol_ctx,
 129                                    struct eapol_callbacks *eapol_cb,
 130                                    struct eap_config *eap_conf);
 131 void eap_server_sm_deinit(struct eap_sm *sm);
 132 int eap_server_sm_step(struct eap_sm *sm);
 133 void eap_sm_notify_cached(struct eap_sm *sm);
 134 void eap_sm_pending_cb(struct eap_sm *sm);
 135 int eap_sm_method_pending(struct eap_sm *sm);
 136 const u8 * eap_get_identity(struct eap_sm *sm, size_t *len);
 137 struct eap_eapol_interface * eap_get_interface(struct eap_sm *sm);
 138
 139 #include <eap_server/eap_i.h>
 140
 141 static OM_uint32
 142 initTls(OM_uint32 *minor,
 143         gss_ctx_id_t ctx)
 144 {
 145     struct tls_config tconf;
 146     struct tls_connection_params tparams;
 147
 148     memset(&tconf, 0, sizeof(tconf));
 149     ctx->acceptorCtx.tlsContext = tls_init(&tconf);
 150     if (ctx->acceptorCtx.tlsContext == NULL)
 151         return GSS_S_FAILURE;
 152
 153     memset(&tparams, 0, sizeof(tparams));
 154     tparams.ca_cert = "ca.pem";
 155     tparams.client_cert = "server.pem";
 156     tparams.private_key = "server-key.pem";
 157
 158     if (tls_global_set_params(ctx->acceptorCtx.tlsContext, &tparams)) {
 159         return GSS_S_FAILURE;
 160     }
 161
 162     if (tls_global_set_verify(ctx->acceptorCtx.tlsContext, 0)) {
 163         return GSS_S_FAILURE;
 164     }
 165
 166     return GSS_S_COMPLETE;
 167 }
 168
 169 static int
 170 serverGetEapUser(void *ctx,
 171                  const unsigned char *identity,
 172                  size_t identityLength,
 173                  int phase2,
 174                  struct eap_user *user)
 175 {
 176     gss_ctx_id_t gssCtx = (gss_ctx_id_t)ctx;
 177     OM_uint32 major, minor;
 178     gss_buffer_desc buf;
 179
 180     memset(user, 0, sizeof(*user));
 181
 182     buf.length = identityLength;
 183     buf.value = (void *)identity;
 184
 185     if (phase2 == 0) {
 186         user->methods[0].vendor = EAP_VENDOR_IETF;
 187         user->methods[0].method = EAP_TYPE_PEAP;
 188         return 0;
 189     }
 190
 191     major = gssEapImportName(&minor, &buf, GSS_C_NT_USER_NAME,
 192                              &gssCtx->initiatorName);
 193     if (GSS_ERROR(major))
 194         return -1;
 195
 196     /*
 197      * OK, obviously there is no real security here, this is simply
 198      * for testing the token exchange; this code will be completely
 199      * replaced with libradsec once that library is available.
 200      */
 201     user->methods[0].vendor = EAP_VENDOR_IETF;
 202     user->methods[0].method = EAP_TYPE_MSCHAPV2;
 203     user->password = (unsigned char *)strdup(" ");
 204     user->password_len = 1;
 205
 206     return 0;
 207 }
 208
 209 static const char *
 210 serverGetEapReqIdText(void *ctx,
 211                       size_t *len)
 212 {
 213     *len = 0;
 214     return NULL;
 215 }
 216 #endif
 217
 218 static OM_uint32
 219 completeAccept(OM_uint32 *minor, gss_ctx_id_t ctx)
 220 {
 221     OM_uint32 major;
 222     krb5_context krbContext;
 223
 224     GSSEAP_KRB_INIT(&krbContext);
 225
 226     /* Cache encryption type derived from selected mechanism OID */
 227     major = gssEapOidToEnctype(minor, ctx->mechanismUsed, &ctx->encryptionType);
 228     if (GSS_ERROR(major))
 229         return major;
 230
 231     if (ctx->encryptionType != ENCTYPE_NULL &&
 232         ctx->acceptorCtx.eapPolInterface->eapKeyAvailable) {
 233         major = gssEapDeriveRFC3961Key(minor,
 234                                        ctx->acceptorCtx.eapPolInterface->eapKeyData,
 235                                        ctx->acceptorCtx.eapPolInterface->eapKeyDataLen,
 236                                        ctx->encryptionType,
 237                                        &ctx->rfc3961Key);
 238         if (GSS_ERROR(major))
 239             return major;
 240     } else {
 241         /*
 242          * draft-howlett-eap-gss says that integrity/confidentialty should
 243          * always be advertised as available, but if we have no keying
 244          * material it seems confusing to the caller to advertise this.
 245          */
 246         ctx->gssFlags &= ~(GSS_C_INTEG_FLAG | GSS_C_CONF_FLAG);
 247     }
 248
 249     sequenceInit(&ctx->seqState, ctx->recvSeq,
 250                  ((ctx->gssFlags & GSS_C_REPLAY_FLAG) != 0),
 251                  ((ctx->gssFlags & GSS_C_SEQUENCE_FLAG) != 0),
 252                  TRUE);
 253
 254     return GSS_S_COMPLETE;
 255 }
 256
 257 static OM_uint32
 258 eapGssSmAcceptAuthenticate(OM_uint32 *minor,
 259                            gss_ctx_id_t ctx,
 260                            gss_cred_id_t cred,
 261                            gss_buffer_t inputToken,
 262                            gss_channel_bindings_t chanBindings,
 263                            gss_buffer_t outputToken)
 264 {
 265     OM_uint32 major;
 266     OM_uint32 tmpMinor, tmpMajor;
 267     int code;
 268     struct wpabuf respData;
 269     static struct eapol_callbacks cb = { serverGetEapUser, serverGetEapReqIdText };
 270     if (ctx->acceptorCtx.eap == NULL) {
 271         struct eap_config eapConfig;
 272
 273         major = initTls(minor, ctx);
 274         if (GSS_ERROR(major))
 275             goto cleanup;
 276
 277         memset(&eapConfig, 0, sizeof(eapConfig));
 278         eapConfig.eap_server = 1;
 279         eapConfig.ssl_ctx = ctx->acceptorCtx.tlsContext;
 280
 281         ctx->acceptorCtx.eap = eap_server_sm_init(ctx, &cb, &eapConfig);
 282         if (ctx->acceptorCtx.eap == NULL) {
 283             major = GSS_S_FAILURE;
 284             goto cleanup;
 285         }
 286
 287         ctx->acceptorCtx.eapPolInterface = eap_get_interface(ctx->acceptorCtx.eap);
 288         ctx->acceptorCtx.eapPolInterface->portEnabled = TRUE;
 289         ctx->acceptorCtx.eapPolInterface->eapRestart = TRUE;
 290     }
 291
 292     if (ctx->acceptorName == GSS_C_NO_NAME &&
 293         cred != GSS_C_NO_CREDENTIAL &&
 294         cred->name != GSS_C_NO_NAME) {
 295         major = gss_duplicate_name(minor, cred->name, &ctx->acceptorName);
 296         if (GSS_ERROR(major))
 297             goto cleanup;
 298     }
 299
 300     wpabuf_set(&respData, inputToken->value, inputToken->length);
 301     ctx->acceptorCtx.eapPolInterface->eapRespData = &respData;
 302     ctx->acceptorCtx.eapPolInterface->eapResp = TRUE;
 303
 304     code = eap_server_sm_step(ctx->acceptorCtx.eap);
 305
 306     if (ctx->acceptorCtx.eapPolInterface->eapReq) {
 307         ctx->acceptorCtx.eapPolInterface->eapReq = 0;
 308         major = GSS_S_CONTINUE_NEEDED;
 309     }
 310
 311     if (ctx->acceptorCtx.eapPolInterface->eapSuccess) {
 312         ctx->acceptorCtx.eapPolInterface->eapSuccess = 0;
 313         ctx->state = EAP_STATE_ESTABLISHED;
 314         major = completeAccept(minor, ctx);
 315     } else if (ctx->acceptorCtx.eapPolInterface->eapFail) {
 316         ctx->acceptorCtx.eapPolInterface->eapFail = 0;
 317         major = GSS_S_FAILURE;
 318     } else if (code == 0) {
 319         major = GSS_S_FAILURE;
 320     }
 321
 322     if (ctx->acceptorCtx.eapPolInterface->eapReqData != NULL) {
 323         gss_buffer_desc buf;
 324
 325         buf.length = wpabuf_len(ctx->acceptorCtx.eapPolInterface->eapReqData);
 326         buf.value = (void *)wpabuf_head(ctx->acceptorCtx.eapPolInterface->eapReqData);
 327
 328         tmpMajor = duplicateBuffer(&tmpMinor, &buf, outputToken);
 329         if (GSS_ERROR(tmpMajor)) {
 330             major = tmpMajor;
 331             *minor = tmpMinor;
 332             goto cleanup;
 333         }
 334     }
 335
 336 cleanup:
 337     ctx->acceptorCtx.eapPolInterface->eapRespData = NULL;
 338
 339     return major;
 340 }
 341
 342 static OM_uint32
 343 eapGssSmAcceptEstablished(OM_uint32 *minor,
 344                           gss_ctx_id_t ctx,
 345                           gss_cred_id_t cred,
 346                           gss_buffer_t inputToken,
 347                           gss_channel_bindings_t chanBindings,
 348                           gss_buffer_t outputToken)
 349 {
 350     /* Called with already established context */
 351     *minor = EINVAL;
 352     return GSS_S_BAD_STATUS;
 353 }
 354
 355 static struct eap_gss_acceptor_sm {
 356     enum gss_eap_token_type inputTokenType;
 357     enum gss_eap_token_type outputTokenType;
 358     OM_uint32 (*processToken)(OM_uint32 *,
 359                               gss_ctx_id_t,
 360                               gss_cred_id_t,
 361                               gss_buffer_t,
 362                               gss_channel_bindings_t,
 363                               gss_buffer_t);
 364 } eapGssAcceptorSm[] = {
 365     { TOK_TYPE_EAP_RESP,    TOK_TYPE_EAP_REQ,  eapGssSmAcceptAuthenticate   },
 366     { TOK_TYPE_EAP_RESP,    TOK_TYPE_EAP_REQ,  NULL                         },
 367     { TOK_TYPE_EAP_RESP,    TOK_TYPE_EAP_REQ,  NULL                         },
 368     { TOK_TYPE_GSS_CB,      TOK_TYPE_NONE,     NULL                         },
 369     { TOK_TYPE_NONE,        TOK_TYPE_NONE,     eapGssSmAcceptEstablished    },
 370 };
 371
 372 OM_uint32
 373 gss_accept_sec_context(OM_uint32 *minor,
 374                        gss_ctx_id_t *context_handle,
 375                        gss_cred_id_t cred,
 376                        gss_buffer_t input_token,
 377                        gss_channel_bindings_t input_chan_bindings,
 378                        gss_name_t *src_name,
 379                        gss_OID *mech_type,
 380                        gss_buffer_t output_token,
 381                        OM_uint32 *ret_flags,
 382                        OM_uint32 *time_rec,
 383                        gss_cred_id_t *delegated_cred_handle)
 384 {
 385     OM_uint32 major;
 386     OM_uint32 tmpMajor, tmpMinor;
 387     gss_ctx_id_t ctx = *context_handle;
 388     struct eap_gss_acceptor_sm *sm = NULL;
 389     gss_buffer_desc innerInputToken, innerOutputToken;
 390
 391     *minor = 0;
 392
 393     innerOutputToken.length = 0;
 394     innerOutputToken.value = NULL;
 395
 396     output_token->length = 0;
 397     output_token->value = NULL;
 398
 399     if (cred != GSS_C_NO_CREDENTIAL && !(cred->flags & CRED_FLAG_ACCEPT)) {
 400         return GSS_S_NO_CRED;
 401     }
 402
 403     if (input_token == GSS_C_NO_BUFFER || input_token->length == 0) {
 404         return GSS_S_DEFECTIVE_TOKEN;
 405     }
 406
 407     if (ctx == GSS_C_NO_CONTEXT) {
 408         major = gssEapAllocContext(minor, &ctx);
 409         if (GSS_ERROR(major))
 410             return major;
 411
 412         *context_handle = ctx;
 413     }
 414
 415     GSSEAP_MUTEX_LOCK(&ctx->mutex);
 416
 417     sm = &eapGssAcceptorSm[ctx->state];
 418
 419     major = gssEapVerifyToken(minor, ctx, input_token,
 420                               sm->inputTokenType, &innerInputToken);
 421     if (GSS_ERROR(major))
 422         goto cleanup;
 423
 424     do {
 425         major = (sm->processToken)(minor,
 426                                    ctx,
 427                                    cred,
 428                                    &innerInputToken,
 429                                    input_chan_bindings,
 430                                    &innerOutputToken);
 431         if (GSS_ERROR(major))
 432             goto cleanup;
 433     } while (major == GSS_S_CONTINUE_NEEDED && innerOutputToken.length == 0);
 434
 435     if (mech_type != NULL) {
 436         if (!gssEapInternalizeOid(ctx->mechanismUsed, mech_type))
 437             duplicateOid(&tmpMinor, ctx->mechanismUsed, mech_type);
 438     }
 439     if (innerOutputToken.length != 0) {
 440         tmpMajor = gssEapMakeToken(&tmpMinor, ctx, &innerOutputToken,
 441                                    sm->outputTokenType, output_token);
 442         if (GSS_ERROR(tmpMajor)) {
 443             major = tmpMajor;
 444             *minor = tmpMinor;
 445             goto cleanup;
 446         }
 447     }
 448     if (ret_flags != NULL)
 449         *ret_flags = ctx->gssFlags;
 450     if (delegated_cred_handle != NULL)
 451         *delegated_cred_handle = GSS_C_NO_CREDENTIAL;
 452
 453     if (major == GSS_S_COMPLETE) {
 454         if (src_name != NULL && ctx->initiatorName != GSS_C_NO_NAME) {
 455             major = gss_duplicate_name(&tmpMinor, ctx->initiatorName, src_name);
 456             if (GSS_ERROR(major))
 457                 goto cleanup;
 458         }
 459         if (time_rec != NULL)
 460             gss_context_time(&tmpMinor, ctx, time_rec);
 461     }
 462
 463     assert(ctx->state == EAP_STATE_ESTABLISHED || major == GSS_S_CONTINUE_NEEDED);
 464
 465 cleanup:
 466     GSSEAP_MUTEX_UNLOCK(&ctx->mutex);
 467
 468     if (GSS_ERROR(major))
 469         gssEapReleaseContext(&tmpMinor, context_handle);
 470
 471     gss_release_buffer(&tmpMinor, &innerOutputToken);
 472
 473     return major;
 474 }